/*
* Copyright 2015-2019 Leonid Yuriev <leo@yuriev.ru>
* and other libmdbx authors: please see AUTHORS file.
* All rights reserved.
*
* This code is derived from "LMDB engine" written by
* Howard Chu (Symas Corporation), which itself derived from btree.c
* written by Martin Hedenfalk.
*
* ---
*
* Portions Copyright 2011-2015 Howard Chu, Symas Corp. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted only as authorized by the OpenLDAP
* Public License.
*
* A copy of this license is available in the file LICENSE in the
* top-level directory of the distribution or, alternatively, at
* <http://www.OpenLDAP.org/license.html>.
*
* ---
*
* Portions Copyright (c) 2009, 2010 Martin Hedenfalk <martin@bzero.se>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
#include "./bits.h"
/*----------------------------------------------------------------------------*/
/* Internal inlines */
static __inline bool mdbx_is_power2(size_t x) { return (x & (x - 1)) == 0; }
static __inline size_t mdbx_roundup2(size_t value, size_t granularity) {
assert(mdbx_is_power2(granularity));
return (value + granularity - 1) & ~(granularity - 1);
}
static __inline unsigned mdbx_log2(size_t value) {
assert(mdbx_is_power2(value));
unsigned log = 0;
while (value > 1) {
log += 1;
value >>= 1;
}
return log;
}
/* Address of node i in page p */
static __inline MDBX_node *NODEPTR(MDBX_page *p, unsigned i) {
assert(NUMKEYS(p) > (unsigned)(i));
return (MDBX_node *)((char *)(p) + (p)->mp_ptrs[i] + PAGEHDRSZ);
}
/* Get the page number pointed to by a branch node */
static __inline pgno_t NODEPGNO(const MDBX_node *node) {
pgno_t pgno;
if (UNALIGNED_OK) {
pgno = node->mn_ksize_and_pgno;
if (sizeof(pgno_t) > 4)
pgno &= MAX_PAGENO;
} else {
pgno = node->mn_lo | ((pgno_t)node->mn_hi << 16);
if (sizeof(pgno_t) > 4)
pgno |= ((uint64_t)node->mn_flags) << 32;
}
return pgno;
}
/* Set the page number in a branch node */
static __inline void SETPGNO(MDBX_node *node, pgno_t pgno) {
assert(pgno <= MAX_PAGENO);
if (UNALIGNED_OK) {
if (sizeof(pgno_t) > 4)
pgno |= ((uint64_t)node->mn_ksize) << 48;
node->mn_ksize_and_pgno = pgno;
} else {
node->mn_lo = (uint16_t)pgno;
node->mn_hi = (uint16_t)(pgno >> 16);
if (sizeof(pgno_t) > 4)
node->mn_flags = (uint16_t)((uint64_t)pgno >> 32);
}
}
/* Get the size of the data in a leaf node */
static __inline size_t NODEDSZ(const MDBX_node *node) {
size_t size;
if (UNALIGNED_OK) {
size = node->mn_dsize;
} else {
size = node->mn_lo | ((size_t)node->mn_hi << 16);
}
return size;
}
/* Set the size of the data for a leaf node */
static __inline void SETDSZ(MDBX_node *node, size_t size) {
assert(size < INT_MAX);
if (UNALIGNED_OK) {
node->mn_dsize = (uint32_t)size;
} else {
node->mn_lo = (uint16_t)size;
node->mn_hi = (uint16_t)(size >> 16);
}
}
static __inline size_t pgno2bytes(const MDBX_env *env, pgno_t pgno) {
mdbx_assert(env, (1u << env->me_psize2log) == env->me_psize);
return ((size_t)pgno) << env->me_psize2log;
}
static __inline MDBX_page *pgno2page(const MDBX_env *env, pgno_t pgno) {
return (MDBX_page *)(env->me_map + pgno2bytes(env, pgno));
}
static __inline pgno_t bytes2pgno(const MDBX_env *env, size_t bytes) {
mdbx_assert(env, (env->me_psize >> env->me_psize2log) == 1);
return (pgno_t)(bytes >> env->me_psize2log);
}
static __inline size_t pgno_align2os_bytes(const MDBX_env *env, pgno_t pgno) {
return mdbx_roundup2(pgno2bytes(env, pgno), env->me_os_psize);
}
static __inline pgno_t pgno_align2os_pgno(const MDBX_env *env, pgno_t pgno) {
return bytes2pgno(env, pgno_align2os_bytes(env, pgno));
}
/* Perform act while tracking temporary cursor mn */
#define WITH_CURSOR_TRACKING(mn, act) \
do { \
mdbx_cassert(&(mn), \
mn.mc_txn->mt_cursors != NULL /* must be not rdonly txt */); \
MDBX_cursor mc_dummy, *tracked, \
**tp = &(mn).mc_txn->mt_cursors[mn.mc_dbi]; \
if ((mn).mc_flags & C_SUB) { \
mc_dummy.mc_flags = C_INITIALIZED; \
mc_dummy.mc_xcursor = (MDBX_xcursor *)&(mn); \
tracked = &mc_dummy; \
} else { \
tracked = &(mn); \
} \
tracked->mc_next = *tp; \
*tp = tracked; \
{ act; } \
*tp = tracked->mc_next; \
} while (0)
/*----------------------------------------------------------------------------*/
/* LY: temporary workaround for Elbrus's memcmp() bug. */
#if defined(__e2k__) && !__GLIBC_PREREQ(2, 24)
int __hot mdbx_e2k_memcmp_bug_workaround(const void *s1, const void *s2,
size_t n) {
if (unlikely(n > 42
/* LY: align followed access if reasonable possible */
&& (((uintptr_t)s1) & 7) != 0 &&
(((uintptr_t)s1) & 7) == (((uintptr_t)s2) & 7))) {
if (((uintptr_t)s1) & 1) {
const int diff = *(uint8_t *)s1 - *(uint8_t *)s2;
if (diff)
return diff;
s1 = (char *)s1 + 1;
s2 = (char *)s2 + 1;
n -= 1;
}
if (((uintptr_t)s1) & 2) {
const uint16_t a = *(uint16_t *)s1;
const uint16_t b = *(uint16_t *)s2;
if (likely(a != b))
return (__builtin_bswap16(a) > __builtin_bswap16(b)) ? 1 : -1;
s1 = (char *)s1 + 2;
s2 = (char *)s2 + 2;
n -= 2;
}
if (((uintptr_t)s1) & 4) {
const uint32_t a = *(uint32_t *)s1;
const uint32_t b = *(uint32_t *)s2;
if (likely(a != b))
return (__builtin_bswap32(a) > __builtin_bswap32(b)) ? 1 : -1;
s1 = (char *)s1 + 4;
s2 = (char *)s2 + 4;
n -= 4;
}
}
while (n >= 8) {
const uint64_t a = *(uint64_t *)s1;
const uint64_t b = *(uint64_t *)s2;
if (likely(a != b))
return (__builtin_bswap64(a) > __builtin_bswap64(b)) ? 1 : -1;
s1 = (char *)s1 + 8;
s2 = (char *)s2 + 8;
n -= 8;
}
if (n & 4) {
const uint32_t a = *(uint32_t *)s1;
const uint32_t b = *(uint32_t *)s2;
if (likely(a != b))
return (__builtin_bswap32(a) > __builtin_bswap32(b)) ? 1 : -1;
s1 = (char *)s1 + 4;
s2 = (char *)s2 + 4;
}
if (n & 2) {
const uint16_t a = *(uint16_t *)s1;
const uint16_t b = *(uint16_t *)s2;
if (likely(a != b))
return (__builtin_bswap16(a) > __builtin_bswap16(b)) ? 1 : -1;
s1 = (char *)s1 + 2;
s2 = (char *)s2 + 2;
}
return (n & 1) ? *(uint8_t *)s1 - *(uint8_t *)s2 : 0;
}
int __hot mdbx_e2k_strcmp_bug_workaround(const char *s1, const char *s2) {
while (true) {
int diff = *(uint8_t *)s1 - *(uint8_t *)s2;
if (likely(diff != 0) || *s1 == '\0')
return diff;
s1 += 1;
s2 += 1;
}
}
int __hot mdbx_e2k_strncmp_bug_workaround(const char *s1, const char *s2,
size_t n) {
while (n > 0) {
int diff = *(uint8_t *)s1 - *(uint8_t *)s2;
if (likely(diff != 0) || *s1 == '\0')
return diff;
s1 += 1;
s2 += 1;
n -= 1;
}
return 0;
}
size_t __hot mdbx_e2k_strlen_bug_workaround(const char *s) {
size_t n = 0;
while (*s) {
s += 1;
n += 1;
}
return n;
}
size_t __hot mdbx_e2k_strnlen_bug_workaround(const char *s, size_t maxlen) {
size_t n = 0;
while (maxlen > n && *s) {
s += 1;
n += 1;
}
return n;
}
#endif /* Elbrus's memcmp() bug. */
/*----------------------------------------------------------------------------*/
/* rthc (tls keys and destructors) */
typedef struct rthc_entry_t {
MDBX_reader *begin;
MDBX_reader *end;
mdbx_thread_key_t key;
} rthc_entry_t;
#if MDBX_DEBUG
#define RTHC_INITIAL_LIMIT 1
#else
#define RTHC_INITIAL_LIMIT 16
#endif
#if defined(_WIN32) || defined(_WIN64)
static CRITICAL_SECTION rthc_critical_section;
#else
int __cxa_thread_atexit_impl(void (*dtor)(void *), void *obj, void *dso_symbol)
__attribute__((weak));
static pthread_mutex_t mdbx_rthc_mutex = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t mdbx_rthc_cond = PTHREAD_COND_INITIALIZER;
static mdbx_thread_key_t mdbx_rthc_key;
static volatile uint32_t mdbx_rthc_pending;
static void __cold mdbx_workaround_glibc_bug21031(void) {
/* Workaround for https://sourceware.org/bugzilla/show_bug.cgi?id=21031
*
* Due race between pthread_key_delete() and __nptl_deallocate_tsd()
* The destructor(s) of thread-local-storate object(s) may be running
* in another thread(s) and be blocked or not finished yet.
* In such case we get a SEGFAULT after unload this library DSO.
*
* So just by yielding a few timeslices we give a chance
* to such destructor(s) for completion and avoids segfault. */
sched_yield();
sched_yield();
sched_yield();
}
#endif
static unsigned rthc_count, rthc_limit;
static rthc_entry_t *rthc_table;
static rthc_entry_t rthc_table_static[RTHC_INITIAL_LIMIT];
static __cold void mdbx_rthc_lock(void) {
#if defined(_WIN32) || defined(_WIN64)
EnterCriticalSection(&rthc_critical_section);
#else
mdbx_ensure(nullptr, pthread_mutex_lock(&mdbx_rthc_mutex) == 0);
#endif
}
static __cold void mdbx_rthc_unlock(void) {
#if defined(_WIN32) || defined(_WIN64)
LeaveCriticalSection(&rthc_critical_section);
#else
mdbx_ensure(nullptr, pthread_mutex_unlock(&mdbx_rthc_mutex) == 0);
#endif
}
static __inline int mdbx_thread_key_create(mdbx_thread_key_t *key) {
int rc;
#if defined(_WIN32) || defined(_WIN64)
*key = TlsAlloc();
rc = (*key != TLS_OUT_OF_INDEXES) ? MDBX_SUCCESS : GetLastError();
#else
rc = pthread_key_create(key, nullptr);
#endif
mdbx_trace("&key = %p, value 0x%x, rc %d", key, (unsigned)*key, rc);
return rc;
}
static __inline void mdbx_thread_key_delete(mdbx_thread_key_t key) {
mdbx_trace("key = 0x%x", (unsigned)key);
#if defined(_WIN32) || defined(_WIN64)
mdbx_ensure(nullptr, TlsFree(key));
#else
mdbx_ensure(nullptr, pthread_key_delete(key) == 0);
mdbx_workaround_glibc_bug21031();
#endif
}
static __inline void *mdbx_thread_rthc_get(mdbx_thread_key_t key) {
#if defined(_WIN32) || defined(_WIN64)
return TlsGetValue(key);
#else
return pthread_getspecific(key);
#endif
}
static void mdbx_thread_rthc_set(mdbx_thread_key_t key, const void *value) {
#if defined(_WIN32) || defined(_WIN64)
mdbx_ensure(nullptr, TlsSetValue(key, (void *)value));
#else
#define MDBX_THREAD_RTHC_ZERO 0
#define MDBX_THREAD_RTHC_REGISTERD 1
#define MDBX_THREAD_RTHC_COUNTED 2
static __thread uint32_t thread_registration_state;
if (value && unlikely(thread_registration_state == MDBX_THREAD_RTHC_ZERO)) {
thread_registration_state = MDBX_THREAD_RTHC_REGISTERD;
mdbx_trace("thread registered 0x%" PRIxPTR, (uintptr_t)mdbx_thread_self());
if (&__cxa_thread_atexit_impl == nullptr ||
__cxa_thread_atexit_impl(mdbx_rthc_thread_dtor,
&thread_registration_state,
(void *)&mdbx_version /* dso_anchor */)) {
mdbx_ensure(nullptr, pthread_setspecific(
mdbx_rthc_key, &thread_registration_state) == 0);
thread_registration_state = MDBX_THREAD_RTHC_COUNTED;
const unsigned count_before = mdbx_atomic_add32(&mdbx_rthc_pending, 1);
mdbx_ensure(nullptr, count_before < INT_MAX);
mdbx_trace("fallback to pthreads' tsd, key 0x%x, count %u",
(unsigned)mdbx_rthc_key, count_before);
(void)count_before;
}
}
mdbx_ensure(nullptr, pthread_setspecific(key, value) == 0);
#endif
}
__cold void mdbx_rthc_global_init(void) {
rthc_limit = RTHC_INITIAL_LIMIT;
rthc_table = rthc_table_static;
#if defined(_WIN32) || defined(_WIN64)
InitializeCriticalSection(&rthc_critical_section);
#else
mdbx_ensure(nullptr,
pthread_key_create(&mdbx_rthc_key, mdbx_rthc_thread_dtor) == 0);
mdbx_trace("pid %d, &mdbx_rthc_key = %p, value 0x%x", mdbx_getpid(),
&mdbx_rthc_key, (unsigned)mdbx_rthc_key);
#endif
}
/* dtor called for thread, i.e. for all mdbx's environment objects */
__cold void mdbx_rthc_thread_dtor(void *ptr) {
mdbx_rthc_lock();
mdbx_trace(">> pid %d, thread 0x%" PRIxPTR ", rthc %p", mdbx_getpid(),
(uintptr_t)mdbx_thread_self(), ptr);
const mdbx_pid_t self_pid = mdbx_getpid();
for (unsigned i = 0; i < rthc_count; ++i) {
const mdbx_thread_key_t key = rthc_table[i].key;
MDBX_reader *const rthc = mdbx_thread_rthc_get(key);
if (rthc < rthc_table[i].begin || rthc >= rthc_table[i].end)
continue;
#if !defined(_WIN32) && !defined(_WIN64)
if (pthread_setspecific(key, nullptr) != 0) {
mdbx_trace("== thread 0x%" PRIxPTR
", rthc %p: ignore race with tsd-key deletion",
(uintptr_t)mdbx_thread_self(), ptr);
continue /* ignore race with tsd-key deletion by mdbx_env_close() */;
}
#endif
mdbx_trace("== thread 0x%" PRIxPTR
", rthc %p, [%i], %p ... %p (%+i), rtch-pid %i, "
"current-pid %i",
(uintptr_t)mdbx_thread_self(), rthc, i, rthc_table[i].begin,
rthc_table[i].end, (int)(rthc - rthc_table[i].begin),
rthc->mr_pid, self_pid);
if (rthc->mr_pid == self_pid) {
mdbx_trace("==== thread 0x%" PRIxPTR ", rthc %p, cleanup",
(uintptr_t)mdbx_thread_self(), rthc);
rthc->mr_pid = 0;
}
}
#if defined(_WIN32) || defined(_WIN64)
mdbx_trace("<< thread 0x%" PRIxPTR ", rthc %p", (uintptr_t)mdbx_thread_self(),
ptr);
mdbx_rthc_unlock();
#else
const char self_registration = *(char *)ptr;
*(char *)ptr = MDBX_THREAD_RTHC_ZERO;
mdbx_trace("== thread 0x%" PRIxPTR ", rthc %p, pid %d, self-status %d",
(uintptr_t)mdbx_thread_self(), ptr, mdbx_getpid(),
self_registration);
if (self_registration == MDBX_THREAD_RTHC_COUNTED)
mdbx_ensure(nullptr, mdbx_atomic_sub32(&mdbx_rthc_pending, 1) > 0);
if (mdbx_rthc_pending == 0) {
mdbx_trace("== thread 0x%" PRIxPTR ", rthc %p, pid %d, wake",
(uintptr_t)mdbx_thread_self(), ptr, mdbx_getpid());
mdbx_ensure(nullptr, pthread_cond_broadcast(&mdbx_rthc_cond) == 0);
}
mdbx_trace("<< thread 0x%" PRIxPTR ", rthc %p", (uintptr_t)mdbx_thread_self(),
ptr);
/* Allow tail call optimization, i.e. gcc should generate the jmp instruction
* instead of a call for pthread_mutex_unlock() and therefore CPU could not
* return to current DSO's code section, which may be unloaded immediately
* after the mutex got released. */
pthread_mutex_unlock(&mdbx_rthc_mutex);
#endif
}
__cold void mdbx_rthc_global_dtor(void) {
mdbx_trace(
">> pid %d, &mdbx_rthc_global_dtor %p, &mdbx_rthc_thread_dtor = %p, "
"&mdbx_rthc_remove = %p",
mdbx_getpid(), &mdbx_rthc_global_dtor, &mdbx_rthc_thread_dtor,
&mdbx_rthc_remove);
mdbx_rthc_lock();
#if !defined(_WIN32) && !defined(_WIN64)
char *rthc = (char *)pthread_getspecific(mdbx_rthc_key);
mdbx_trace("== thread 0x%" PRIxPTR ", rthc %p, pid %d, self-status %d",
(uintptr_t)mdbx_thread_self(), rthc, mdbx_getpid(),
rthc ? *rthc : -1);
if (rthc) {
const char self_registration = *(char *)rthc;
*rthc = MDBX_THREAD_RTHC_ZERO;
if (self_registration == MDBX_THREAD_RTHC_COUNTED)
mdbx_ensure(nullptr, mdbx_atomic_sub32(&mdbx_rthc_pending, 1) > 0);
}
struct timespec abstime;
mdbx_ensure(nullptr, clock_gettime(CLOCK_REALTIME, &abstime) == 0);
abstime.tv_nsec += 1000000000l / 10;
if (abstime.tv_nsec >= 1000000000l) {
abstime.tv_nsec -= 1000000000l;
abstime.tv_sec += 1;
}
#if MDBX_DEBUG > 0
abstime.tv_sec += 600;
#endif
for (unsigned left; (left = mdbx_rthc_pending) > 0;) {
mdbx_trace("pid %d, pending %u, wait for...", mdbx_getpid(), left);
const int rc =
pthread_cond_timedwait(&mdbx_rthc_cond, &mdbx_rthc_mutex, &abstime);
if (rc && rc != EINTR)
break;
}
mdbx_thread_key_delete(mdbx_rthc_key);
#endif
const mdbx_pid_t self_pid = mdbx_getpid();
for (unsigned i = 0; i < rthc_count; ++i) {
const mdbx_thread_key_t key = rthc_table[i].key;
mdbx_thread_key_delete(key);
for (MDBX_reader *rthc = rthc_table[i].begin; rthc < rthc_table[i].end;
++rthc) {
mdbx_trace("== [%i] = key %u, %p ... %p, rthc %p (%+i), "
"rthc-pid %i, current-pid %i",
i, key, rthc_table[i].begin, rthc_table[i].end, rthc,
(int)(rthc - rthc_table[i].begin), rthc->mr_pid, self_pid);
if (rthc->mr_pid == self_pid) {
rthc->mr_pid = 0;
mdbx_trace("== cleanup %p", rthc);
}
}
}
rthc_limit = rthc_count = 0;
if (rthc_table != rthc_table_static)
mdbx_free(rthc_table);
rthc_table = nullptr;
mdbx_rthc_unlock();
#if defined(_WIN32) || defined(_WIN64)
DeleteCriticalSection(&rthc_critical_section);
#else
/* LY: yielding a few timeslices to give a more chance
* to racing destructor(s) for completion. */
mdbx_workaround_glibc_bug21031();
#endif
mdbx_trace("<< pid %d\n", mdbx_getpid());
}
__cold int mdbx_rthc_alloc(mdbx_thread_key_t *key, MDBX_reader *begin,
MDBX_reader *end) {
#ifndef NDEBUG
*key = (mdbx_thread_key_t)0xBADBADBAD;
#endif /* NDEBUG */
int rc = mdbx_thread_key_create(key);
if (rc != MDBX_SUCCESS)
return rc;
mdbx_rthc_lock();
mdbx_trace(">> key 0x%x, rthc_count %u, rthc_limit %u", *key, rthc_count,
rthc_limit);
if (rthc_count == rthc_limit) {
rthc_entry_t *new_table =
mdbx_realloc((rthc_table == rthc_table_static) ? nullptr : rthc_table,
sizeof(rthc_entry_t) * rthc_limit * 2);
if (new_table == nullptr) {
rc = MDBX_ENOMEM;
goto bailout;
}
if (rthc_table == rthc_table_static)
memcpy(new_table, rthc_table_static, sizeof(rthc_table_static));
rthc_table = new_table;
rthc_limit *= 2;
}
mdbx_trace("== [%i] = key %u, %p ... %p", rthc_count, *key, begin, end);
rthc_table[rthc_count].key = *key;
rthc_table[rthc_count].begin = begin;
rthc_table[rthc_count].end = end;
++rthc_count;
mdbx_trace("<< key 0x%x, rthc_count %u, rthc_limit %u", *key, rthc_count,
rthc_limit);
mdbx_rthc_unlock();
return MDBX_SUCCESS;
bailout:
mdbx_thread_key_delete(*key);
mdbx_rthc_unlock();
return rc;
}
__cold void mdbx_rthc_remove(const mdbx_thread_key_t key) {
mdbx_thread_key_delete(key);
mdbx_rthc_lock();
mdbx_trace(">> key 0x%x, rthc_count %u, rthc_limit %u", key, rthc_count,
rthc_limit);
for (unsigned i = 0; i < rthc_count; ++i) {
if (key == rthc_table[i].key) {
const mdbx_pid_t self_pid = mdbx_getpid();
mdbx_trace("== [%i], %p ...%p, current-pid %d", i, rthc_table[i].begin,
rthc_table[i].end, self_pid);
for (MDBX_reader *rthc = rthc_table[i].begin; rthc < rthc_table[i].end;
++rthc) {
if (rthc->mr_pid == self_pid) {
rthc->mr_pid = 0;
mdbx_trace("== cleanup %p", rthc);
}
}
if (--rthc_count > 0)
rthc_table[i] = rthc_table[rthc_count];
else if (rthc_table != rthc_table_static) {
mdbx_free(rthc_table);
rthc_table = rthc_table_static;
rthc_limit = RTHC_INITIAL_LIMIT;
}
break;
}
}
mdbx_trace("<< key 0x%x, rthc_count %u, rthc_limit %u", key, rthc_count,
rthc_limit);
mdbx_rthc_unlock();
}
/*----------------------------------------------------------------------------*/
static __inline size_t pnl2bytes(const size_t size) {
assert(size > 0 && size <= MDBX_PNL_MAX * 2);
size_t bytes =
mdbx_roundup2(MDBX_ASSUME_MALLOC_OVERHEAD + sizeof(pgno_t) * (size + 2),
MDBX_PNL_GRANULATE * sizeof(pgno_t)) -
MDBX_ASSUME_MALLOC_OVERHEAD;
return bytes;
}
static __inline pgno_t bytes2pnl(const size_t bytes) {
size_t size = bytes / sizeof(pgno_t);
assert(size > 2 && size <= MDBX_PNL_MAX * 2);
return (pgno_t)size - 2;
}
static MDBX_PNL mdbx_pnl_alloc(size_t size) {
const size_t bytes = pnl2bytes(size);
MDBX_PNL pl = mdbx_malloc(bytes);
if (likely(pl)) {
#if __GLIBC_PREREQ(2, 12)
const size_t bytes = malloc_usable_size(pl);
#endif
pl[0] = bytes2pnl(bytes);
assert(pl[0] >= size);
pl[1] = 0;
pl += 1;
}
return pl;
}
static void mdbx_pnl_free(MDBX_PNL pl) {
if (likely(pl))
mdbx_free(pl - 1);
}
/* Shrink the PNL to the default size if it has grown larger */
static void mdbx_pnl_shrink(MDBX_PNL *ppl) {
assert(bytes2pnl(pnl2bytes(MDBX_PNL_INITIAL)) == MDBX_PNL_INITIAL);
assert(MDBX_PNL_SIZE(*ppl) <= MDBX_PNL_MAX &&
MDBX_PNL_ALLOCLEN(*ppl) >= MDBX_PNL_SIZE(*ppl));
MDBX_PNL_SIZE(*ppl) = 0;
if (unlikely(MDBX_PNL_ALLOCLEN(*ppl) >
MDBX_PNL_INITIAL + MDBX_CACHELINE_SIZE / sizeof(pgno_t))) {
const size_t bytes = pnl2bytes(MDBX_PNL_INITIAL);
MDBX_PNL pl = mdbx_realloc(*ppl - 1, bytes);
if (likely(pl)) {
#if __GLIBC_PREREQ(2, 12)
const size_t bytes = malloc_usable_size(pl);
#endif
*pl = bytes2pnl(bytes);
*ppl = pl + 1;
}
}
}
/* Grow the PNL to the size growed to at least given size */
static int mdbx_pnl_reserve(MDBX_PNL *ppl, const size_t wanna) {
const size_t allocated = MDBX_PNL_ALLOCLEN(*ppl);
assert(MDBX_PNL_SIZE(*ppl) <= MDBX_PNL_MAX &&
MDBX_PNL_ALLOCLEN(*ppl) >= MDBX_PNL_SIZE(*ppl));
if (likely(allocated >= wanna))
return MDBX_SUCCESS;
if (unlikely(wanna > /* paranoia */ MDBX_PNL_MAX))
return MDBX_TXN_FULL;
const size_t size = (wanna + wanna - allocated < MDBX_PNL_MAX)
? wanna + wanna - allocated
: MDBX_PNL_MAX;
const size_t bytes = pnl2bytes(size);
MDBX_PNL pl = mdbx_realloc(*ppl - 1, bytes);
if (likely(pl)) {
#if __GLIBC_PREREQ(2, 12)
const size_t bytes = malloc_usable_size(pl);
#endif
*pl = bytes2pnl(bytes);
assert(*pl >= wanna);
*ppl = pl + 1;
return MDBX_SUCCESS;
}
return MDBX_ENOMEM;
}
/* Make room for num additional elements in an PNL */
static __inline int __must_check_result mdbx_pnl_need(MDBX_PNL *ppl,
size_t num) {
assert(MDBX_PNL_SIZE(*ppl) <= MDBX_PNL_MAX &&
MDBX_PNL_ALLOCLEN(*ppl) >= MDBX_PNL_SIZE(*ppl));
assert(num <= MDBX_PNL_MAX);
const size_t wanna = MDBX_PNL_SIZE(*ppl) + num;
return likely(MDBX_PNL_ALLOCLEN(*ppl) >= wanna)
? MDBX_SUCCESS
: mdbx_pnl_reserve(ppl, wanna);
}
static __inline void mdbx_pnl_xappend(MDBX_PNL pl, pgno_t id) {
assert(MDBX_PNL_SIZE(pl) < MDBX_PNL_ALLOCLEN(pl));
MDBX_PNL_SIZE(pl) += 1;
MDBX_PNL_LAST(pl) = id;
}
/* Append an ID onto an PNL */
static int __must_check_result mdbx_pnl_append(MDBX_PNL *ppl, pgno_t id) {
/* Too big? */
if (unlikely(MDBX_PNL_SIZE(*ppl) == MDBX_PNL_ALLOCLEN(*ppl))) {
int rc = mdbx_pnl_need(ppl, MDBX_PNL_GRANULATE);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
mdbx_pnl_xappend(*ppl, id);
return MDBX_SUCCESS;
}
/* Append an PNL onto an PNL */
static int __must_check_result mdbx_pnl_append_list(MDBX_PNL *ppl,
MDBX_PNL append) {
int rc = mdbx_pnl_need(ppl, MDBX_PNL_SIZE(append));
if (unlikely(rc != MDBX_SUCCESS))
return rc;
memcpy(MDBX_PNL_END(*ppl), MDBX_PNL_BEGIN(append),
MDBX_PNL_SIZE(append) * sizeof(pgno_t));
MDBX_PNL_SIZE(*ppl) += MDBX_PNL_SIZE(append);
return MDBX_SUCCESS;
}
/* Append an ID range onto an PNL */
static int __must_check_result mdbx_pnl_append_range(MDBX_PNL *ppl, pgno_t id,
size_t n) {
int rc = mdbx_pnl_need(ppl, n);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
pgno_t *ap = MDBX_PNL_END(*ppl);
MDBX_PNL_SIZE(*ppl) += (unsigned)n;
for (pgno_t *const end = MDBX_PNL_END(*ppl); ap < end;)
*ap++ = id++;
return MDBX_SUCCESS;
}
static bool mdbx_pnl_check(MDBX_PNL pl, bool allocated) {
if (pl) {
assert(MDBX_PNL_SIZE(pl) <= MDBX_PNL_MAX);
if (allocated) {
assert(MDBX_PNL_ALLOCLEN(pl) >= MDBX_PNL_SIZE(pl));
}
for (const pgno_t *scan = &MDBX_PNL_LAST(pl); --scan > pl;) {
assert(MDBX_PNL_ORDERED(scan[0], scan[1]));
assert(scan[0] >= NUM_METAS);
if (unlikely(MDBX_PNL_DISORDERED(scan[0], scan[1]) ||
scan[0] < NUM_METAS))
return false;
}
}
return true;
}
/* Merge an PNL onto an PNL. The destination PNL must be big enough */
static void __hot mdbx_pnl_xmerge(MDBX_PNL pnl, MDBX_PNL merge) {
assert(mdbx_pnl_check(pnl, true));
assert(mdbx_pnl_check(merge, false));
pgno_t old_id, merge_id, i = MDBX_PNL_SIZE(merge), j = MDBX_PNL_SIZE(pnl),
k = i + j, total = k;
pnl[0] =
MDBX_PNL_ASCENDING ? 0 : ~(pgno_t)0; /* delimiter for pl scan below */
old_id = pnl[j];
while (i) {
merge_id = merge[i--];
for (; MDBX_PNL_ORDERED(merge_id, old_id); old_id = pnl[--j])
pnl[k--] = old_id;
pnl[k--] = merge_id;
}
MDBX_PNL_SIZE(pnl) = total;
assert(mdbx_pnl_check(pnl, true));
}
/* Sort an PNL */
static void __hot mdbx_pnl_sort(MDBX_PNL pnl) {
/* Max possible depth of int-indexed tree * 2 items/level */
int istack[sizeof(int) * CHAR_BIT * 2];
int i, j, k, l, ir, jstack;
pgno_t a;
/* Quicksort + Insertion sort for small arrays */
#define PNL_SMALL 8
#define PNL_SWAP(a, b) \
do { \
pgno_t tmp_pgno = (a); \
(a) = (b); \
(b) = tmp_pgno; \
} while (0)
ir = (int)MDBX_PNL_SIZE(pnl);
l = 1;
jstack = 0;
while (1) {
if (ir - l < PNL_SMALL) { /* Insertion sort */
for (j = l + 1; j <= ir; j++) {
a = pnl[j];
for (i = j - 1; i >= 1; i--) {
if (MDBX_PNL_DISORDERED(a, pnl[i]))
break;
pnl[i + 1] = pnl[i];
}
pnl[i + 1] = a;
}
if (jstack == 0)
break;
ir = istack[jstack--];
l = istack[jstack--];
} else {
k = (l + ir) >> 1; /* Choose median of left, center, right */
PNL_SWAP(pnl[k], pnl[l + 1]);
if (MDBX_PNL_ORDERED(pnl[ir], pnl[l]))
PNL_SWAP(pnl[l], pnl[ir]);
if (MDBX_PNL_ORDERED(pnl[ir], pnl[l + 1]))
PNL_SWAP(pnl[l + 1], pnl[ir]);
if (MDBX_PNL_ORDERED(pnl[l + 1], pnl[l]))
PNL_SWAP(pnl[l], pnl[l + 1]);
i = l + 1;
j = ir;
a = pnl[l + 1];
while (1) {
do
i++;
while (MDBX_PNL_ORDERED(pnl[i], a));
do
j--;
while (MDBX_PNL_ORDERED(a, pnl[j]));
if (j < i)
break;
PNL_SWAP(pnl[i], pnl[j]);
}
pnl[l + 1] = pnl[j];
pnl[j] = a;
jstack += 2;
if (ir - i + 1 >= j - l) {
istack[jstack] = ir;
istack[jstack - 1] = i;
ir = j - 1;
} else {
istack[jstack] = j - 1;
istack[jstack - 1] = l;
l = i;
}
}
}
#undef PNL_SMALL
#undef PNL_SWAP
assert(mdbx_pnl_check(pnl, false));
}
/* Search for an ID in an PNL.
* [in] pl The PNL to search.
* [in] id The ID to search for.
* Returns The index of the first ID greater than or equal to id. */
static unsigned __hot mdbx_pnl_search(MDBX_PNL pnl, pgno_t id) {
assert(mdbx_pnl_check(pnl, true));
/* binary search of id in pl
* if found, returns position of id
* if not found, returns first position greater than id */
unsigned base = 0;
unsigned cursor = 1;
int val = 0;
unsigned n = MDBX_PNL_SIZE(pnl);
while (n > 0) {
unsigned pivot = n >> 1;
cursor = base + pivot + 1;
val = MDBX_PNL_ASCENDING ? mdbx_cmp2int(id, pnl[cursor])
: mdbx_cmp2int(pnl[cursor], id);
if (val < 0) {
n = pivot;
} else if (val > 0) {
base = cursor;
n -= pivot + 1;
} else {
return cursor;
}
}
if (val > 0)
++cursor;
return cursor;
}
/*----------------------------------------------------------------------------*/
static __inline size_t txl2bytes(const size_t size) {
assert(size > 0 && size <= MDBX_TXL_MAX * 2);
size_t bytes =
mdbx_roundup2(MDBX_ASSUME_MALLOC_OVERHEAD + sizeof(txnid_t) * (size + 2),
MDBX_TXL_GRANULATE * sizeof(txnid_t)) -
MDBX_ASSUME_MALLOC_OVERHEAD;
return bytes;
}
static __inline size_t bytes2txl(const size_t bytes) {
size_t size = bytes / sizeof(txnid_t);
assert(size > 2 && size <= MDBX_TXL_MAX * 2);
return size - 2;
}
static MDBX_TXL mdbx_txl_alloc(void) {
const size_t bytes = txl2bytes(MDBX_TXL_INITIAL);
MDBX_TXL tl = mdbx_malloc(bytes);
if (likely(tl)) {
#if __GLIBC_PREREQ(2, 12)
const size_t bytes = malloc_usable_size(tl);
#endif
tl[0] = bytes2txl(bytes);
assert(tl[0] >= MDBX_TXL_INITIAL);
tl[1] = 0;
tl += 1;
}
return tl;
}
static void mdbx_txl_free(MDBX_TXL tl) {
if (likely(tl))
mdbx_free(tl - 1);
}
static int mdbx_txl_reserve(MDBX_TXL *ptl, const size_t wanna) {
const size_t allocated = (size_t)MDBX_PNL_ALLOCLEN(*ptl);
assert(MDBX_PNL_SIZE(*ptl) <= MDBX_TXL_MAX &&
MDBX_PNL_ALLOCLEN(*ptl) >= MDBX_PNL_SIZE(*ptl));
if (likely(allocated >= wanna))
return MDBX_SUCCESS;
if (unlikely(wanna > /* paranoia */ MDBX_TXL_MAX))
return MDBX_TXN_FULL;
const size_t size = (wanna + wanna - allocated < MDBX_TXL_MAX)
? wanna + wanna - allocated
: MDBX_TXL_MAX;
const size_t bytes = txl2bytes(size);
MDBX_TXL tl = mdbx_realloc(*ptl - 1, bytes);
if (likely(tl)) {
#if __GLIBC_PREREQ(2, 12)
const size_t bytes = malloc_usable_size(tl);
#endif
*tl = bytes2txl(bytes);
assert(*tl >= wanna);
*ptl = tl + 1;
return MDBX_SUCCESS;
}
return MDBX_ENOMEM;
}
static __inline int __must_check_result mdbx_txl_need(MDBX_TXL *ptl,
size_t num) {
assert(MDBX_PNL_SIZE(*ptl) <= MDBX_TXL_MAX &&
MDBX_PNL_ALLOCLEN(*ptl) >= MDBX_PNL_SIZE(*ptl));
assert(num <= MDBX_PNL_MAX);
const size_t wanna = (size_t)MDBX_PNL_SIZE(*ptl) + num;
return likely(MDBX_PNL_ALLOCLEN(*ptl) >= wanna)
? MDBX_SUCCESS
: mdbx_txl_reserve(ptl, wanna);
}
static __inline void mdbx_txl_xappend(MDBX_TXL tl, txnid_t id) {
assert(MDBX_PNL_SIZE(tl) < MDBX_PNL_ALLOCLEN(tl));
MDBX_PNL_SIZE(tl) += 1;
MDBX_PNL_LAST(tl) = id;
}
static int mdbx_txl_cmp(const void *pa, const void *pb) {
const txnid_t a = *(MDBX_TXL)pa;
const txnid_t b = *(MDBX_TXL)pb;
return mdbx_cmp2int(b, a);
}
static void mdbx_txl_sort(MDBX_TXL ptr) {
/* LY: temporary */
qsort(ptr + 1, (size_t)ptr[0], sizeof(*ptr), mdbx_txl_cmp);
}
static int __must_check_result mdbx_txl_append(MDBX_TXL *ptl, txnid_t id) {
if (unlikely(MDBX_PNL_SIZE(*ptl) == MDBX_PNL_ALLOCLEN(*ptl))) {
int rc = mdbx_txl_need(ptl, MDBX_TXL_GRANULATE);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
mdbx_txl_xappend(*ptl, id);
return MDBX_SUCCESS;
}
static int __must_check_result mdbx_txl_append_list(MDBX_TXL *ptl,
MDBX_TXL append) {
int rc = mdbx_txl_need(ptl, (size_t)MDBX_PNL_SIZE(append));
if (unlikely(rc != MDBX_SUCCESS))
return rc;
memcpy(MDBX_PNL_END(*ptl), MDBX_PNL_BEGIN(append),
(size_t)MDBX_PNL_SIZE(append) * sizeof(txnid_t));
MDBX_PNL_SIZE(*ptl) += MDBX_PNL_SIZE(append);
return MDBX_SUCCESS;
}
/*----------------------------------------------------------------------------*/
/* Returns the index of the first dirty-page whose pgno
* member is greater than or equal to id. */
static unsigned __hot mdbx_dpl_search(MDBX_DPL dl, pgno_t id) {
/* binary search of id in array
* if found, returns position of id
* if not found, returns first position greater than id */
unsigned base = 0;
unsigned cursor = 1;
int val = 0;
unsigned n = dl->length;
#if MDBX_DEBUG
for (const MDBX_DP *ptr = dl + dl->length; --ptr > dl;) {
assert(ptr[0].pgno < ptr[1].pgno);
assert(ptr[0].pgno >= NUM_METAS);
}
#endif
while (n > 0) {
unsigned pivot = n >> 1;
cursor = base + pivot + 1;
val = mdbx_cmp2int(id, dl[cursor].pgno);
if (val < 0) {
n = pivot;
} else if (val > 0) {
base = cursor;
n -= pivot + 1;
} else {
return cursor;
}
}
if (val > 0)
++cursor;
return cursor;
}
static int mdbx_dpl_cmp(const void *pa, const void *pb) {
const MDBX_DP a = *(MDBX_DPL)pa;
const MDBX_DP b = *(MDBX_DPL)pb;
return mdbx_cmp2int(a.pgno, b.pgno);
}
static void mdbx_dpl_sort(MDBX_DPL dl) {
assert(dl->length <= MDBX_DPL_TXNFULL);
/* LY: temporary */
qsort(dl + 1, dl->length, sizeof(*dl), mdbx_dpl_cmp);
}
static int __must_check_result mdbx_dpl_insert(MDBX_DPL dl, pgno_t pgno,
MDBX_page *page) {
assert(dl->length <= MDBX_DPL_TXNFULL);
unsigned x = mdbx_dpl_search(dl, pgno);
assert((int)x > 0);
if (unlikely(dl[x].pgno == pgno && x <= dl->length))
return /* duplicate */ MDBX_PROBLEM;
if (unlikely(dl->length == MDBX_DPL_TXNFULL))
return MDBX_TXN_FULL;
/* insert page */
for (unsigned i = dl->length += 1; i > x; --i)
dl[i] = dl[i - 1];
dl[x].pgno = pgno;
dl[x].ptr = page;
return MDBX_SUCCESS;
}
static int __must_check_result mdbx_dpl_append(MDBX_DPL dl, pgno_t pgno,
MDBX_page *page) {
assert(dl->length <= MDBX_DPL_TXNFULL);
#if MDBX_DEBUG
for (unsigned i = dl->length; i > 0; --i) {
assert(dl[i].pgno != pgno);
if (unlikely(dl[i].pgno == pgno))
return MDBX_PROBLEM;
}
#endif
if (unlikely(dl->length == MDBX_DPL_TXNFULL))
return MDBX_TXN_FULL;
/* append page */
const unsigned i = dl->length += 1;
dl[i].pgno = pgno;
dl[i].ptr = page;
return MDBX_SUCCESS;
}
/*----------------------------------------------------------------------------*/
int mdbx_runtime_flags = MDBX_DBG_PRINT
#if MDBX_DEBUG
| MDBX_DBG_ASSERT
#endif
#if MDBX_DEBUG > 1
| MDBX_DBG_TRACE
#endif
#if MDBX_DEBUG > 2
| MDBX_DBG_AUDIT
#endif
#if MDBX_DEBUG > 3
| MDBX_DBG_EXTRA
#endif
;
MDBX_debug_func *mdbx_debug_logger;
static int mdbx_page_alloc(MDBX_cursor *mc, unsigned num, MDBX_page **mp,
int flags);
static int mdbx_page_new(MDBX_cursor *mc, uint32_t flags, unsigned num,
MDBX_page **mp);
static int mdbx_page_touch(MDBX_cursor *mc);
static int mdbx_cursor_touch(MDBX_cursor *mc);
#define MDBX_END_NAMES \
{ \
"committed", "empty-commit", "abort", "reset", "reset-tmp", "fail-begin", \
"fail-beginchild" \
}
enum {
/* mdbx_txn_end operation number, for logging */
MDBX_END_COMMITTED,
MDBX_END_EMPTY_COMMIT,
MDBX_END_ABORT,
MDBX_END_RESET,
MDBX_END_RESET_TMP,
MDBX_END_FAIL_BEGIN,
MDBX_END_FAIL_BEGINCHILD
};
#define MDBX_END_OPMASK 0x0F /* mask for mdbx_txn_end() operation number */
#define MDBX_END_UPDATE 0x10 /* update env state (DBIs) */
#define MDBX_END_FREE 0x20 /* free txn unless it is MDBX_env.me_txn0 */
#define MDBX_END_EOTDONE 0x40 /* txn's cursors already closed */
#define MDBX_END_SLOT 0x80 /* release any reader slot if MDBX_NOTLS */
static int mdbx_txn_end(MDBX_txn *txn, unsigned mode);
static int __must_check_result mdbx_page_get(MDBX_cursor *mc, pgno_t pgno,
MDBX_page **mp, int *lvl);
static int __must_check_result mdbx_page_search_root(MDBX_cursor *mc,
MDBX_val *key, int modify);
#define MDBX_PS_MODIFY 1
#define MDBX_PS_ROOTONLY 2
#define MDBX_PS_FIRST 4
#define MDBX_PS_LAST 8
static int __must_check_result mdbx_page_search(MDBX_cursor *mc, MDBX_val *key,
int flags);
static int __must_check_result mdbx_page_merge(MDBX_cursor *csrc,
MDBX_cursor *cdst);
#define MDBX_SPLIT_REPLACE MDBX_APPENDDUP /* newkey is not new */
static int __must_check_result mdbx_page_split(MDBX_cursor *mc,
const MDBX_val *newkey,
MDBX_val *newdata,
pgno_t newpgno, unsigned nflags);
static int __must_check_result mdbx_read_header(MDBX_env *env, MDBX_meta *meta,
uint64_t *filesize);
static int __must_check_result mdbx_sync_locked(MDBX_env *env, unsigned flags,
MDBX_meta *const pending);
static void mdbx_env_close0(MDBX_env *env);
static MDBX_node *mdbx_node_search(MDBX_cursor *mc, MDBX_val *key, int *exactp);
static int __must_check_result mdbx_node_add_branch(MDBX_cursor *mc,
unsigned indx,
const MDBX_val *key,
pgno_t pgno);
static int __must_check_result mdbx_node_add_leaf(MDBX_cursor *mc,
unsigned indx,
const MDBX_val *key,
MDBX_val *data,
unsigned flags);
static int __must_check_result mdbx_node_add_leaf2(MDBX_cursor *mc,
unsigned indx,
const MDBX_val *key);
static void mdbx_node_del(MDBX_cursor *mc, size_t ksize);
static void mdbx_node_shrink(MDBX_page *mp, unsigned indx);
static int __must_check_result mdbx_node_move(MDBX_cursor *csrc,
MDBX_cursor *cdst, int fromleft);
static int __must_check_result mdbx_node_read(MDBX_cursor *mc, MDBX_node *leaf,
MDBX_val *data);
static size_t mdbx_leaf_size(MDBX_env *env, const MDBX_val *key,
const MDBX_val *data);
static size_t mdbx_branch_size(MDBX_env *env, const MDBX_val *key);
static int __must_check_result mdbx_rebalance(MDBX_cursor *mc);
static int __must_check_result mdbx_update_key(MDBX_cursor *mc,
const MDBX_val *key);
static void mdbx_cursor_pop(MDBX_cursor *mc);
static int __must_check_result mdbx_cursor_push(MDBX_cursor *mc, MDBX_page *mp);
static int __must_check_result mdbx_cursor_check(MDBX_cursor *mc, bool pending);
static int __must_check_result mdbx_cursor_del0(MDBX_cursor *mc);
static int __must_check_result mdbx_del0(MDBX_txn *txn, MDBX_dbi dbi,
MDBX_val *key, MDBX_val *data,
unsigned flags);
static int __must_check_result mdbx_cursor_sibling(MDBX_cursor *mc,
int move_right);
static int __must_check_result mdbx_cursor_next(MDBX_cursor *mc, MDBX_val *key,
MDBX_val *data,
MDBX_cursor_op op);
static int __must_check_result mdbx_cursor_prev(MDBX_cursor *mc, MDBX_val *key,
MDBX_val *data,
MDBX_cursor_op op);
static int __must_check_result mdbx_cursor_set(MDBX_cursor *mc, MDBX_val *key,
MDBX_val *data,
MDBX_cursor_op op, int *exactp);
static int __must_check_result mdbx_cursor_first(MDBX_cursor *mc, MDBX_val *key,
MDBX_val *data);
static int __must_check_result mdbx_cursor_last(MDBX_cursor *mc, MDBX_val *key,
MDBX_val *data);
static int __must_check_result mdbx_cursor_init(MDBX_cursor *mc, MDBX_txn *txn,
MDBX_dbi dbi);
static int __must_check_result mdbx_xcursor_init0(MDBX_cursor *mc);
static int __must_check_result mdbx_xcursor_init1(MDBX_cursor *mc,
MDBX_node *node);
static int __must_check_result mdbx_xcursor_init2(MDBX_cursor *mc,
MDBX_xcursor *src_mx,
int force);
static int __must_check_result mdbx_drop0(MDBX_cursor *mc, int subs);
static MDBX_cmp_func mdbx_cmp_memn, mdbx_cmp_memnr, mdbx_cmp_int_ai,
mdbx_cmp_int_a2, mdbx_cmp_int_ua;
static const char *__mdbx_strerr(int errnum) {
/* Table of descriptions for MDBX errors */
static const char *const tbl[] = {
"MDBX_KEYEXIST: Key/data pair already exists",
"MDBX_NOTFOUND: No matching key/data pair found",
"MDBX_PAGE_NOTFOUND: Requested page not found",
"MDBX_CORRUPTED: Database is corrupted",
"MDBX_PANIC: Update of meta page failed or environment had fatal error",
"MDBX_VERSION_MISMATCH: DB version mismatch libmdbx",
"MDBX_INVALID: File is not an MDBX file",
"MDBX_MAP_FULL: Environment mapsize limit reached",
"MDBX_DBS_FULL: Too may DBI (maxdbs reached)",
"MDBX_READERS_FULL: Too many readers (maxreaders reached)",
NULL /* MDBX_TLS_FULL (-30789): unused in MDBX */,
"MDBX_TXN_FULL: Transaction has too many dirty pages - transaction too "
"big",
"MDBX_CURSOR_FULL: Internal error - cursor stack limit reached",
"MDBX_PAGE_FULL: Internal error - page has no more space",
"MDBX_MAP_RESIZED: Database contents grew beyond environment mapsize",
"MDBX_INCOMPATIBLE: Operation and DB incompatible, or DB flags changed",
"MDBX_BAD_RSLOT: Invalid reuse of reader locktable slot",
"MDBX_BAD_TXN: Transaction must abort, has a child, or is invalid",
"MDBX_BAD_VALSIZE: Unsupported size of key/DB name/data, or wrong "
"DUPFIXED size",
"MDBX_BAD_DBI: The specified DBI handle was closed/changed unexpectedly",
"MDBX_PROBLEM: Unexpected problem - txn should abort",
"MDBX_BUSY: Another write transaction is started",
};
if (errnum >= MDBX_KEYEXIST && errnum <= MDBX_LAST_ERRCODE) {
int i = errnum - MDBX_KEYEXIST;
return tbl[i];
}
switch (errnum) {
case MDBX_SUCCESS:
return "MDBX_SUCCESS: Successful";
case MDBX_EMULTIVAL:
return "MDBX_EMULTIVAL: Unable to update multi-value for the given key";
case MDBX_EBADSIGN:
return "MDBX_EBADSIGN: Wrong signature of a runtime object(s)";
case MDBX_WANNA_RECOVERY:
return "MDBX_WANNA_RECOVERY: Database should be recovered, but this could "
"NOT be done in a read-only mode";
case MDBX_EKEYMISMATCH:
return "MDBX_EKEYMISMATCH: The given key value is mismatched to the "
"current cursor position";
case MDBX_TOO_LARGE:
return "MDBX_TOO_LARGE: Database is too large for current system, "
"e.g. could NOT be mapped into RAM";
case MDBX_THREAD_MISMATCH:
return "MDBX_THREAD_MISMATCH: A thread has attempted to use a not "
"owned object, e.g. a transaction that started by another thread";
default:
return NULL;
}
}
const char *__cold mdbx_strerror_r(int errnum, char *buf, size_t buflen) {
const char *msg = __mdbx_strerr(errnum);
if (!msg) {
if (!buflen || buflen > INT_MAX)
return NULL;
#if defined(_WIN32) || defined(_WIN64)
size_t size = FormatMessageA(
FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL,
errnum, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf, (DWORD)buflen,
NULL);
return size ? buf : NULL;
#elif defined(_GNU_SOURCE)
/* GNU-specific */
msg = strerror_r(errnum, buf, buflen);
#elif (_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600)
/* XSI-compliant */
int rc = strerror_r(errnum, buf, buflen);
if (rc) {
rc = snprintf(buf, buflen, "error %d", errnum);
assert(rc > 0);
}
return buf;
#else
strncpy(buf, strerror(errnum), buflen);
buf[buflen - 1] = '\0';
return buf;
#endif
}
return msg;
}
const char *__cold mdbx_strerror(int errnum) {
const char *msg = __mdbx_strerr(errnum);
if (!msg) {
#if defined(_WIN32) || defined(_WIN64)
static char buffer[1024];
size_t size = FormatMessageA(
FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL,
errnum, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buffer,
sizeof(buffer), NULL);
if (size)
msg = buffer;
#else
if (errnum < 0) {
static char buffer[32];
int rc = snprintf(buffer, sizeof(buffer) - 1, "unknown error %d", errnum);
assert(rc > 0);
(void)rc;
return buffer;
}
msg = strerror(errnum);
#endif
}
return msg;
}
static txnid_t mdbx_oomkick(MDBX_env *env, const txnid_t laggard);
void __cold mdbx_debug_log(int type, const char *function, int line,
const char *fmt, ...) {
va_list args;
va_start(args, fmt);
if (mdbx_debug_logger)
mdbx_debug_logger(type, function, line, fmt, args);
else {
#if defined(_WIN32) || defined(_WIN64)
if (IsDebuggerPresent()) {
int prefix_len = 0;
char *prefix = nullptr;
if (function && line > 0)
prefix_len = mdbx_asprintf(&prefix, "%s:%d ", function, line);
else if (function)
prefix_len = mdbx_asprintf(&prefix, "%s: ", function);
else if (line > 0)
prefix_len = mdbx_asprintf(&prefix, "%d: ", line);
if (prefix_len > 0 && prefix) {
OutputDebugStringA(prefix);
mdbx_free(prefix);
}
char *msg = nullptr;
int msg_len = mdbx_vasprintf(&msg, fmt, args);
if (msg_len > 0 && msg) {
OutputDebugStringA(msg);
mdbx_free(msg);
}
}
#else
if (function && line > 0)
fprintf(stderr, "%s:%d ", function, line);
else if (function)
fprintf(stderr, "%s: ", function);
else if (line > 0)
fprintf(stderr, "%d: ", line);
vfprintf(stderr, fmt, args);
fflush(stderr);
#endif
}
va_end(args);
}
/* Dump a key in ascii or hexadecimal. */
char *mdbx_dkey(const MDBX_val *key, char *const buf, const size_t bufsize) {
if (!key)
return "<null>";
if (!buf || bufsize < 4)
return nullptr;
if (!key->iov_len)
return "<empty>";
const uint8_t *const data = key->iov_base;
bool is_ascii = true;
unsigned i;
for (i = 0; is_ascii && i < key->iov_len; i++)
if (data[i] < ' ' || data[i] > 127)
is_ascii = false;
if (is_ascii) {
int len =
snprintf(buf, bufsize, "%.*s",
(key->iov_len > INT_MAX) ? INT_MAX : (int)key->iov_len, data);
assert(len > 0 && (unsigned)len < bufsize);
(void)len;
} else {
char *const detent = buf + bufsize - 2;
char *ptr = buf;
*ptr++ = '<';
for (i = 0; i < key->iov_len; i++) {
const ptrdiff_t left = detent - ptr;
assert(left > 0);
int len = snprintf(ptr, left, "%02x", data[i]);
if (len < 0 || len >= left)
break;
ptr += len;
}
if (ptr < detent) {
ptr[0] = '>';
ptr[1] = '\0';
}
}
return buf;
}
#if 0 /* LY: debug stuff */
static const char *mdbx_leafnode_type(MDBX_node *n) {
static char *const tp[2][2] = {{"", ": DB"}, {": sub-page", ": sub-DB"}};
return F_ISSET(n->mn_flags, F_BIGDATA) ? ": overflow page"
: tp[F_ISSET(n->mn_flags, F_DUPDATA)]
[F_ISSET(n->mn_flags, F_SUBDATA)];
}
/* Display all the keys in the page. */
static void mdbx_page_list(MDBX_page *mp) {
pgno_t pgno = mp->mp_pgno;
const char *type, *state = IS_DIRTY(mp) ? ", dirty" : "";
MDBX_node *node;
unsigned i, nkeys, nsize, total = 0;
MDBX_val key;
DKBUF;
switch (mp->mp_flags &
(P_BRANCH | P_LEAF | P_LEAF2 | P_META | P_OVERFLOW | P_SUBP)) {
case P_BRANCH:
type = "Branch page";
break;
case P_LEAF:
type = "Leaf page";
break;
case P_LEAF | P_SUBP:
type = "Leaf sub-page";
break;
case P_LEAF | P_LEAF2:
type = "Leaf2 page";
break;
case P_LEAF | P_LEAF2 | P_SUBP:
type = "Leaf2 sub-page";
break;
case P_OVERFLOW:
mdbx_print("Overflow page %" PRIu64 " pages %u%s\n", pgno, mp->mp_pages,
state);
return;
case P_META:
mdbx_print("Meta-page %" PRIu64 " txnid %" PRIu64 "\n", pgno,
((MDBX_meta *)PAGEDATA(mp))->mm_txnid);
return;
default:
mdbx_print("Bad page %" PRIu64 " flags 0x%X\n", pgno, mp->mp_flags);
return;
}
nkeys = NUMKEYS(mp);
mdbx_print("%s %" PRIu64 " numkeys %u%s\n", type, pgno, nkeys, state);
for (i = 0; i < nkeys; i++) {
if (IS_LEAF2(mp)) { /* LEAF2 pages have no mp_ptrs[] or node headers */
key.iov_len = nsize = mp->mp_leaf2_ksize;
key.iov_base = LEAF2KEY(mp, i, nsize);
total += nsize;
mdbx_print("key %u: nsize %u, %s\n", i, nsize, DKEY(&key));
continue;
}
node = NODEPTR(mp, i);
key.iov_len = node->mn_ksize;
key.iov_base = node->mn_data;
nsize = NODESIZE + key.iov_len;
if (IS_BRANCH(mp)) {
mdbx_print("key %u: page %" PRIu64 ", %s\n", i, NODEPGNO(node),
DKEY(&key));
total += nsize;
} else {
if (F_ISSET(node->mn_flags, F_BIGDATA))
nsize += sizeof(pgno_t);
else
nsize += NODEDSZ(node);
total += nsize;
nsize += sizeof(indx_t);
mdbx_print("key %u: nsize %u, %s%s\n", i, nsize, DKEY(&key),
mdbx_leafnode_type(node));
}
total = EVEN(total);
}
mdbx_print("Total: header %u + contents %u + unused %u\n",
IS_LEAF2(mp) ? PAGEHDRSZ : PAGEHDRSZ + mp->mp_lower, total,
SIZELEFT(mp));
}
static void mdbx_cursor_chk(MDBX_cursor *mc) {
unsigned i;
MDBX_node *node;
MDBX_page *mp;
if (!mc->mc_snum || !(mc->mc_flags & C_INITIALIZED))
return;
for (i = 0; i < mc->mc_top; i++) {
mp = mc->mc_pg[i];
node = NODEPTR(mp, mc->mc_ki[i]);
if (unlikely(NODEPGNO(node) != mc->mc_pg[i + 1]->mp_pgno))
mdbx_print("oops!\n");
}
if (unlikely(mc->mc_ki[i] >= NUMKEYS(mc->mc_pg[i])))
mdbx_print("ack!\n");
if (XCURSOR_INITED(mc)) {
node = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
if (((node->mn_flags & (F_DUPDATA | F_SUBDATA)) == F_DUPDATA) &&
mc->mc_xcursor->mx_cursor.mc_pg[0] != NODEDATA(node)) {
mdbx_print("blah!\n");
}
}
}
#endif /* 0 */
int mdbx_cmp(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *a,
const MDBX_val *b) {
mdbx_assert(NULL, txn->mt_signature == MDBX_MT_SIGNATURE);
return txn->mt_dbxs[dbi].md_cmp(a, b);
}
int mdbx_dcmp(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *a,
const MDBX_val *b) {
mdbx_assert(NULL, txn->mt_signature == MDBX_MT_SIGNATURE);
return txn->mt_dbxs[dbi].md_dcmp(a, b);
}
/* Allocate memory for a page.
* Re-use old malloc'd pages first for singletons, otherwise just malloc.
* Set MDBX_TXN_ERROR on failure. */
static MDBX_page *mdbx_page_malloc(MDBX_txn *txn, unsigned num) {
MDBX_env *env = txn->mt_env;
MDBX_page *np = env->me_dpages;
size_t size = env->me_psize;
if (likely(num == 1 && np)) {
ASAN_UNPOISON_MEMORY_REGION(np, size);
VALGRIND_MEMPOOL_ALLOC(env, np, size);
VALGRIND_MAKE_MEM_DEFINED(&np->mp_next, sizeof(np->mp_next));
env->me_dpages = np->mp_next;
} else {
size = pgno2bytes(env, num);
np = mdbx_malloc(size);
if (unlikely(!np)) {
txn->mt_flags |= MDBX_TXN_ERROR;
return np;
}
VALGRIND_MEMPOOL_ALLOC(env, np, size);
}
if ((env->me_flags & MDBX_NOMEMINIT) == 0) {
/* For a single page alloc, we init everything after the page header.
* For multi-page, we init the final page; if the caller needed that
* many pages they will be filling in at least up to the last page. */
size_t skip = PAGEHDRSZ;
if (num > 1)
skip += pgno2bytes(env, num - 1);
memset((char *)np + skip, 0, size - skip);
}
#if MDBX_DEBUG
np->mp_pgno = 0;
#endif
VALGRIND_MAKE_MEM_UNDEFINED(np, size);
np->mp_flags = 0;
np->mp_pages = num;
return np;
}
/* Free a dirty page */
static void mdbx_dpage_free(MDBX_env *env, MDBX_page *dp, unsigned pages) {
#if MDBX_DEBUG
dp->mp_pgno = MAX_PAGENO;
#endif
if (pages == 1) {
dp->mp_next = env->me_dpages;
VALGRIND_MEMPOOL_FREE(env, dp);
env->me_dpages = dp;
} else {
/* large pages just get freed directly */
VALGRIND_MEMPOOL_FREE(env, dp);
mdbx_free(dp);
}
}
/* Return all dirty pages to dpage list */
static void mdbx_dlist_free(MDBX_txn *txn) {
MDBX_env *env = txn->mt_env;
MDBX_DPL dl = txn->mt_rw_dirtylist;
size_t i, n = dl->length;
for (i = 1; i <= n; i++) {
MDBX_page *dp = dl[i].ptr;
mdbx_dpage_free(env, dp, IS_OVERFLOW(dp) ? dp->mp_pages : 1);
}
dl->length = 0;
}
static size_t bytes_align2os_bytes(const MDBX_env *env, size_t bytes) {
return mdbx_roundup2(mdbx_roundup2(bytes, env->me_psize), env->me_os_psize);
}
static void __cold mdbx_kill_page(MDBX_env *env, MDBX_page *mp) {
const size_t len = env->me_psize - PAGEHDRSZ;
void *ptr = (env->me_flags & MDBX_WRITEMAP)
? &mp->mp_data
: (void *)((uint8_t *)env->me_pbuf + env->me_psize);
memset(ptr, 0x6F /* 'o', 111 */, len);
if (ptr != &mp->mp_data)
(void)mdbx_pwrite(env->me_fd, ptr, len,
pgno2bytes(env, mp->mp_pgno) + PAGEHDRSZ);
VALGRIND_MAKE_MEM_NOACCESS(&mp->mp_data, len);
ASAN_POISON_MEMORY_REGION(&mp->mp_data, len);
}
static __inline MDBX_db *mdbx_outer_db(MDBX_cursor *mc) {
mdbx_cassert(mc, (mc->mc_flags & C_SUB) != 0);
MDBX_xcursor *mx = container_of(mc->mc_db, MDBX_xcursor, mx_db);
MDBX_cursor_couple *couple = container_of(mx, MDBX_cursor_couple, inner);
mdbx_cassert(mc, mc->mc_db == &couple->outer.mc_xcursor->mx_db);
mdbx_cassert(mc, mc->mc_dbx == &couple->outer.mc_xcursor->mx_dbx);
return couple->outer.mc_db;
}
static int mdbx_page_befree(MDBX_cursor *mc, MDBX_page *mp) {
MDBX_txn *txn = mc->mc_txn;
mdbx_cassert(mc, (mc->mc_flags & C_SUB) == 0);
if (IS_BRANCH(mp)) {
mc->mc_db->md_branch_pages--;
} else if (IS_LEAF(mp)) {
mc->mc_db->md_leaf_pages--;
} else {
mdbx_cassert(mc, IS_OVERFLOW(mp));
mc->mc_db->md_overflow_pages -= mp->mp_pages;
return mdbx_pnl_append_range(&txn->mt_befree_pages, mp->mp_pgno,
mp->mp_pages);
}
return mdbx_pnl_append(&txn->mt_befree_pages, mp->mp_pgno);
}
/* Loosen or free a single page.
*
* Saves single pages to a list for future reuse
* in this same txn. It has been pulled from the freeDB
* and already resides on the dirty list, but has been
* deleted. Use these pages first before pulling again
* from the freeDB.
*
* If the page wasn't dirtied in this txn, just add it
* to this txn's free list. */
static int mdbx_page_loose(MDBX_cursor *mc, MDBX_page *mp) {
int loose = 0;
const pgno_t pgno = mp->mp_pgno;
MDBX_txn *txn = mc->mc_txn;
if (unlikely(mc->mc_flags & C_SUB)) {
MDBX_db *outer = mdbx_outer_db(mc);
if (IS_BRANCH(mp))
outer->md_branch_pages--;
else {
mdbx_cassert(mc, IS_LEAF(mp));
outer->md_leaf_pages--;
}
}
if (IS_BRANCH(mp))
mc->mc_db->md_branch_pages--;
else {
mdbx_cassert(mc, IS_LEAF(mp));
mc->mc_db->md_leaf_pages--;
}
if (IS_DIRTY(mp)) {
if (txn->mt_parent) {
/* LY: TODO: use dedicated flag for tracking parent's dirty pages */
mdbx_cassert(mc, (txn->mt_env->me_flags & MDBX_WRITEMAP) == 0);
MDBX_DP *dl = txn->mt_rw_dirtylist;
/* If txn has a parent,
* make sure the page is in our dirty list. */
if (dl->length) {
unsigned x = mdbx_dpl_search(dl, pgno);
if (x <= dl->length && dl[x].pgno == pgno) {
if (unlikely(mp != dl[x].ptr)) { /* bad cursor? */
mdbx_error("wrong page 0x%p #%" PRIaPGNO
" in the dirtylist[%d], expecting %p",
dl[x].ptr, pgno, x, mp);
mc->mc_flags &= ~(C_INITIALIZED | C_EOF);
txn->mt_flags |= MDBX_TXN_ERROR;
return MDBX_PROBLEM;
}
/* ok, it's ours */
loose = 1;
}
}
} else {
/* no parent txn, so it's just ours */
loose = 1;
}
}
if (loose) {
mdbx_debug("loosen db %d page %" PRIaPGNO, DDBI(mc), mp->mp_pgno);
MDBX_page **link = &NEXT_LOOSE_PAGE(mp);
if (unlikely(txn->mt_env->me_flags & MDBX_PAGEPERTURB))
mdbx_kill_page(txn->mt_env, mp);
mp->mp_flags = P_LOOSE | P_DIRTY;
VALGRIND_MAKE_MEM_UNDEFINED(mp, PAGEHDRSZ);
ASAN_UNPOISON_MEMORY_REGION(link, sizeof(*link));
*link = txn->mt_loose_pages;
txn->mt_loose_pages = mp;
txn->mt_loose_count++;
} else {
int rc = mdbx_pnl_append(&txn->mt_befree_pages, pgno);
mdbx_tassert(txn, rc == MDBX_SUCCESS);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
return MDBX_SUCCESS;
}
/* Set or clear P_KEEP in dirty, non-overflow, non-sub pages watched by txn.
*
* [in] mc A cursor handle for the current operation.
* [in] pflags Flags of the pages to update:
* - P_DIRTY to set P_KEEP,
* - P_DIRTY|P_KEEP to clear it.
* [in] all No shortcuts. Needed except after a full mdbx_page_flush().
*
* Returns 0 on success, non-zero on failure. */
static int mdbx_pages_xkeep(MDBX_cursor *mc, unsigned pflags, bool all) {
const unsigned Mask = P_SUBP | P_DIRTY | P_LOOSE | P_KEEP;
MDBX_txn *txn = mc->mc_txn;
MDBX_cursor *m3, *m0 = mc;
MDBX_xcursor *mx;
MDBX_page *dp, *mp;
MDBX_node *leaf;
unsigned i, j;
int rc = MDBX_SUCCESS, level;
/* Mark pages seen by cursors: First m0, then tracked cursors */
for (i = txn->mt_numdbs;;) {
if (mc->mc_flags & C_INITIALIZED) {
for (m3 = mc;; m3 = &mx->mx_cursor) {
mp = NULL;
for (j = 0; j < m3->mc_snum; j++) {
mp = m3->mc_pg[j];
if ((mp->mp_flags & Mask) == pflags)
mp->mp_flags ^= P_KEEP;
}
mx = m3->mc_xcursor;
/* Proceed to mx if it is at a sub-database */
if (!(mx && (mx->mx_cursor.mc_flags & C_INITIALIZED)))
break;
if (!(mp && IS_LEAF(mp)))
break;
leaf = NODEPTR(mp, m3->mc_ki[j - 1]);
if (!(leaf->mn_flags & F_SUBDATA))
break;
}
}
mc = mc->mc_next;
for (; !mc || mc == m0; mc = txn->mt_cursors[--i])
if (i == 0)
goto mark_done;
}
mark_done:
if (all) {
/* Mark dirty root pages */
for (i = 0; i < txn->mt_numdbs; i++) {
if (txn->mt_dbflags[i] & DB_DIRTY) {
pgno_t pgno = txn->mt_dbs[i].md_root;
if (pgno == P_INVALID)
continue;
if (unlikely((rc = mdbx_page_get(m0, pgno, &dp, &level)) !=
MDBX_SUCCESS))
break;
if ((dp->mp_flags & Mask) == pflags && level <= 1)
dp->mp_flags ^= P_KEEP;
}
}
}
return rc;
}
static int mdbx_page_flush(MDBX_txn *txn, pgno_t keep);
/* Spill pages from the dirty list back to disk.
* This is intended to prevent running into MDBX_TXN_FULL situations,
* but note that they may still occur in a few cases:
*
* 1) our estimate of the txn size could be too small. Currently this
* seems unlikely, except with a large number of MDBX_MULTIPLE items.
*
* 2) child txns may run out of space if their parents dirtied a
* lot of pages and never spilled them. TODO: we probably should do
* a preemptive spill during mdbx_txn_begin() of a child txn, if
* the parent's dirtyroom is below a given threshold.
*
* Otherwise, if not using nested txns, it is expected that apps will
* not run into MDBX_TXN_FULL any more. The pages are flushed to disk
* the same way as for a txn commit, e.g. their P_DIRTY flag is cleared.
* If the txn never references them again, they can be left alone.
* If the txn only reads them, they can be used without any fuss.
* If the txn writes them again, they can be dirtied immediately without
* going thru all of the work of mdbx_page_touch(). Such references are
* handled by mdbx_page_unspill().
*
* Also note, we never spill DB root pages, nor pages of active cursors,
* because we'll need these back again soon anyway. And in nested txns,
* we can't spill a page in a child txn if it was already spilled in a
* parent txn. That would alter the parent txns' data even though
* the child hasn't committed yet, and we'd have no way to undo it if
* the child aborted.
*
* [in] m0 cursor A cursor handle identifying the transaction and
* database for which we are checking space.
* [in] key For a put operation, the key being stored.
* [in] data For a put operation, the data being stored.
*
* Returns 0 on success, non-zero on failure. */
static int mdbx_page_spill(MDBX_cursor *m0, MDBX_val *key, MDBX_val *data) {
MDBX_txn *txn = m0->mc_txn;
MDBX_DPL dl = txn->mt_rw_dirtylist;
if (m0->mc_flags & C_SUB)
return MDBX_SUCCESS;
/* Estimate how much space this op will take */
pgno_t i = m0->mc_db->md_depth;
/* Named DBs also dirty the main DB */
if (m0->mc_dbi >= CORE_DBS)
i += txn->mt_dbs[MAIN_DBI].md_depth;
/* For puts, roughly factor in the key+data size */
if (key)
i += bytes2pgno(txn->mt_env, LEAFSIZE(key, data) + txn->mt_env->me_psize);
i += i; /* double it for good measure */
pgno_t need = i;
if (txn->mt_dirtyroom > i)
return MDBX_SUCCESS;
if (!txn->mt_spill_pages) {
txn->mt_spill_pages = mdbx_pnl_alloc(MDBX_DPL_TXNFULL);
if (unlikely(!txn->mt_spill_pages))
return MDBX_ENOMEM;
} else {
/* purge deleted slots */
MDBX_PNL sl = txn->mt_spill_pages;
pgno_t num = MDBX_PNL_SIZE(sl), j = 0;
for (i = 1; i <= num; i++) {
if ((sl[i] & 1) == 0)
sl[++j] = sl[i];
}
MDBX_PNL_SIZE(sl) = j;
}
/* Preserve pages which may soon be dirtied again */
int rc = mdbx_pages_xkeep(m0, P_DIRTY, true);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
/* Less aggressive spill - we originally spilled the entire dirty list,
* with a few exceptions for cursor pages and DB root pages. But this
* turns out to be a lot of wasted effort because in a large txn many
* of those pages will need to be used again. So now we spill only 1/8th
* of the dirty pages. Testing revealed this to be a good tradeoff,
* better than 1/2, 1/4, or 1/10. */
if (need < MDBX_DPL_TXNFULL / 8)
need = MDBX_DPL_TXNFULL / 8;
/* Save the page IDs of all the pages we're flushing */
/* flush from the tail forward, this saves a lot of shifting later on. */
for (i = dl->length; i && need; i--) {
pgno_t pn = dl[i].pgno << 1;
MDBX_page *dp = dl[i].ptr;
if (dp->mp_flags & (P_LOOSE | P_KEEP))
continue;
/* Can't spill twice,
* make sure it's not already in a parent's spill list. */
if (txn->mt_parent) {
MDBX_txn *tx2;
for (tx2 = txn->mt_parent; tx2; tx2 = tx2->mt_parent) {
if (tx2->mt_spill_pages) {
unsigned j = mdbx_pnl_search(tx2->mt_spill_pages, pn);
if (j <= MDBX_PNL_SIZE(tx2->mt_spill_pages) &&
tx2->mt_spill_pages[j] == pn) {
dp->mp_flags |= P_KEEP;
break;
}
}
}
if (tx2)
continue;
}
rc = mdbx_pnl_append(&txn->mt_spill_pages, pn);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
need--;
}
mdbx_pnl_sort(txn->mt_spill_pages);
/* Flush the spilled part of dirty list */
rc = mdbx_page_flush(txn, i);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
/* Reset any dirty pages we kept that page_flush didn't see */
rc = mdbx_pages_xkeep(m0, P_DIRTY | P_KEEP, i != 0);
bailout:
txn->mt_flags |= rc ? MDBX_TXN_ERROR : MDBX_TXN_SPILLS;
return rc;
}
/*----------------------------------------------------------------------------*/
#define METAPAGE(env, n) (&pgno2page(env, n)->mp_meta)
#define METAPAGE_END(env) METAPAGE(env, NUM_METAS)
static __inline txnid_t meta_txnid(const MDBX_env *env, const MDBX_meta *meta,
bool allow_volatile) {
mdbx_assert(env, meta >= METAPAGE(env, 0) || meta < METAPAGE_END(env));
txnid_t a = meta->mm_txnid_a;
txnid_t b = meta->mm_txnid_b;
if (allow_volatile)
return (a == b) ? a : 0;
mdbx_assert(env, a == b);
return a;
}
static __inline txnid_t mdbx_meta_txnid_stable(const MDBX_env *env,
const MDBX_meta *meta) {
return meta_txnid(env, meta, false);
}
static __inline txnid_t mdbx_meta_txnid_fluid(const MDBX_env *env,
const MDBX_meta *meta) {
return meta_txnid(env, meta, true);
}
static __inline void mdbx_meta_update_begin(const MDBX_env *env,
MDBX_meta *meta, txnid_t txnid) {
mdbx_assert(env, meta >= METAPAGE(env, 0) || meta < METAPAGE_END(env));
mdbx_assert(env, meta->mm_txnid_a < txnid && meta->mm_txnid_b < txnid);
meta->mm_txnid_a = txnid;
(void)env;
mdbx_coherent_barrier();
}
static __inline void mdbx_meta_update_end(const MDBX_env *env, MDBX_meta *meta,
txnid_t txnid) {
mdbx_assert(env, meta >= METAPAGE(env, 0) || meta < METAPAGE_END(env));
mdbx_assert(env, meta->mm_txnid_a == txnid);
mdbx_assert(env, meta->mm_txnid_b < txnid);
mdbx_jitter4testing(true);
meta->mm_txnid_b = txnid;
mdbx_coherent_barrier();
}
static __inline void mdbx_meta_set_txnid(const MDBX_env *env, MDBX_meta *meta,
txnid_t txnid) {
mdbx_assert(env, meta < METAPAGE(env, 0) || meta > METAPAGE_END(env));
meta->mm_txnid_a = txnid;
meta->mm_txnid_b = txnid;
}
static __inline uint64_t mdbx_meta_sign(const MDBX_meta *meta) {
uint64_t sign = MDBX_DATASIGN_NONE;
#if 0 /* TODO */
sign = hippeus_hash64(...);
#else
(void)meta;
#endif
/* LY: newer returns MDBX_DATASIGN_NONE or MDBX_DATASIGN_WEAK */
return (sign > MDBX_DATASIGN_WEAK) ? sign : ~sign;
}
enum meta_choise_mode { prefer_last, prefer_noweak, prefer_steady };
static __inline bool mdbx_meta_ot(const enum meta_choise_mode mode,
const MDBX_env *env, const MDBX_meta *a,
const MDBX_meta *b) {
mdbx_jitter4testing(true);
txnid_t txnid_a = mdbx_meta_txnid_fluid(env, a);
txnid_t txnid_b = mdbx_meta_txnid_fluid(env, b);
mdbx_jitter4testing(true);
switch (mode) {
default:
assert(false);
__unreachable();
/* fall through */
__fallthrough;
case prefer_steady:
if (META_IS_STEADY(a) != META_IS_STEADY(b))
return META_IS_STEADY(b);
/* fall through */
__fallthrough;
case prefer_noweak:
if (META_IS_WEAK(a) != META_IS_WEAK(b))
return !META_IS_WEAK(b);
/* fall through */
__fallthrough;
case prefer_last:
mdbx_jitter4testing(true);
if (txnid_a == txnid_b)
return META_IS_STEADY(b) || (META_IS_WEAK(a) && !META_IS_WEAK(b));
return txnid_a < txnid_b;
}
}
static __inline bool mdbx_meta_eq(const MDBX_env *env, const MDBX_meta *a,
const MDBX_meta *b) {
mdbx_jitter4testing(true);
const txnid_t txnid = mdbx_meta_txnid_fluid(env, a);
if (!txnid || txnid != mdbx_meta_txnid_fluid(env, b))
return false;
mdbx_jitter4testing(true);
if (META_IS_STEADY(a) != META_IS_STEADY(b))
return false;
mdbx_jitter4testing(true);
return true;
}
static int mdbx_meta_eq_mask(const MDBX_env *env) {
MDBX_meta *m0 = METAPAGE(env, 0);
MDBX_meta *m1 = METAPAGE(env, 1);
MDBX_meta *m2 = METAPAGE(env, 2);
int rc = mdbx_meta_eq(env, m0, m1) ? 1 : 0;
if (mdbx_meta_eq(env, m1, m2))
rc += 2;
if (mdbx_meta_eq(env, m2, m0))
rc += 4;
return rc;
}
static __inline MDBX_meta *mdbx_meta_recent(const enum meta_choise_mode mode,
const MDBX_env *env, MDBX_meta *a,
MDBX_meta *b) {
const bool a_older_that_b = mdbx_meta_ot(mode, env, a, b);
mdbx_assert(env, !mdbx_meta_eq(env, a, b));
return a_older_that_b ? b : a;
}
static __inline MDBX_meta *mdbx_meta_ancient(const enum meta_choise_mode mode,
const MDBX_env *env, MDBX_meta *a,
MDBX_meta *b) {
const bool a_older_that_b = mdbx_meta_ot(mode, env, a, b);
mdbx_assert(env, !mdbx_meta_eq(env, a, b));
return a_older_that_b ? a : b;
}
static __inline MDBX_meta *
mdbx_meta_mostrecent(const enum meta_choise_mode mode, const MDBX_env *env) {
MDBX_meta *m0 = METAPAGE(env, 0);
MDBX_meta *m1 = METAPAGE(env, 1);
MDBX_meta *m2 = METAPAGE(env, 2);
MDBX_meta *head = mdbx_meta_recent(mode, env, m0, m1);
head = mdbx_meta_recent(mode, env, head, m2);
return head;
}
static __hot MDBX_meta *mdbx_meta_steady(const MDBX_env *env) {
return mdbx_meta_mostrecent(prefer_steady, env);
}
static __hot MDBX_meta *mdbx_meta_head(const MDBX_env *env) {
return mdbx_meta_mostrecent(prefer_last, env);
}
static __hot txnid_t mdbx_reclaiming_detent(const MDBX_env *env) {
if (F_ISSET(env->me_flags, MDBX_UTTERLY_NOSYNC))
return env->me_txn->mt_txnid - 1;
return mdbx_meta_txnid_stable(env, mdbx_meta_steady(env));
}
static const char *mdbx_durable_str(const MDBX_meta *const meta) {
if (META_IS_WEAK(meta))
return "Weak";
if (META_IS_STEADY(meta))
return (meta->mm_datasync_sign == mdbx_meta_sign(meta)) ? "Steady"
: "Tainted";
return "Legacy";
}
/*----------------------------------------------------------------------------*/
/* Find oldest txnid still referenced. */
static txnid_t mdbx_find_oldest(MDBX_txn *txn) {
mdbx_tassert(txn, (txn->mt_flags & MDBX_RDONLY) == 0);
MDBX_env *env = txn->mt_env;
const txnid_t edge = mdbx_reclaiming_detent(env);
mdbx_tassert(txn, edge <= txn->mt_txnid - 1);
MDBX_lockinfo *const lck = env->me_lck;
if (unlikely(env->me_lck == NULL /* exclusive mode */))
return env->me_oldest_stub = edge;
const txnid_t last_oldest = lck->mti_oldest;
mdbx_tassert(txn, edge >= last_oldest);
if (likely(last_oldest == edge))
return edge;
const uint32_t nothing_changed = MDBX_STRING_TETRAD("None");
const uint32_t snap_readers_refresh_flag = lck->mti_readers_refresh_flag;
mdbx_jitter4testing(false);
if (snap_readers_refresh_flag == nothing_changed)
return last_oldest;
txnid_t oldest = edge;
lck->mti_readers_refresh_flag = nothing_changed;
mdbx_coherent_barrier();
const unsigned snap_nreaders = lck->mti_numreaders;
for (unsigned i = 0; i < snap_nreaders; ++i) {
if (lck->mti_readers[i].mr_pid) {
/* mdbx_jitter4testing(true); */
const txnid_t snap = lck->mti_readers[i].mr_txnid;
if (oldest > snap && last_oldest <= /* ignore pending updates */ snap) {
oldest = snap;
if (oldest == last_oldest)
return oldest;
}
}
}
if (oldest != last_oldest) {
mdbx_notice("update oldest %" PRIaTXN " -> %" PRIaTXN, last_oldest, oldest);
mdbx_tassert(txn, oldest >= lck->mti_oldest);
lck->mti_oldest = oldest;
}
return oldest;
}
/* Add a page to the txn's dirty list */
static int __must_check_result mdbx_page_dirty(MDBX_txn *txn, MDBX_page *mp) {
int (*const adder)(MDBX_DPL, pgno_t pgno, MDBX_page * page) =
(txn->mt_flags & MDBX_TXN_WRITEMAP) ? mdbx_dpl_append : mdbx_dpl_insert;
const int rc = adder(txn->mt_rw_dirtylist, mp->mp_pgno, mp);
if (unlikely(rc != MDBX_SUCCESS)) {
txn->mt_flags |= MDBX_TXN_ERROR;
return rc;
}
txn->mt_dirtyroom--;
return MDBX_SUCCESS;
}
__cold static int mdbx_mapresize(MDBX_env *env, const pgno_t size_pgno,
const pgno_t limit_pgno) {
#ifdef USE_VALGRIND
const size_t prev_mapsize = env->me_mapsize;
void *const prev_mapaddr = env->me_map;
#endif
const size_t limit_bytes = pgno_align2os_bytes(env, limit_pgno);
const size_t size_bytes = pgno_align2os_bytes(env, size_pgno);
mdbx_info("resize datafile/mapping: "
"present %" PRIuPTR " -> %" PRIuPTR ", "
"limit %" PRIuPTR " -> %" PRIuPTR,
env->me_dbgeo.now, size_bytes, env->me_dbgeo.upper, limit_bytes);
mdbx_assert(env, limit_bytes >= size_bytes);
mdbx_assert(env, bytes2pgno(env, size_bytes) == size_pgno);
mdbx_assert(env, bytes2pgno(env, limit_bytes) == limit_pgno);
#if defined(_WIN32) || defined(_WIN64)
/* Acquire guard in exclusive mode for:
* - to avoid collision between read and write txns around env->me_dbgeo;
* - to avoid attachment of new reading threads (see mdbx_rdt_lock); */
mdbx_srwlock_AcquireExclusive(&env->me_remap_guard);
mdbx_handle_array_t *suspended = NULL;
mdbx_handle_array_t array_onstack;
int rc = MDBX_SUCCESS;
if (limit_bytes == env->me_dxb_mmap.length &&
size_bytes == env->me_dxb_mmap.current &&
env->me_dxb_mmap.current == env->me_dxb_mmap.filesize)
goto bailout;
/* 1) Windows allows only extending a read-write section, but not a
* corresponing mapped view. Therefore in other cases we must suspend
* the local threads for safe remap.
* 2) At least on Windows 10 1803 the entire mapped section is unavailable
* for short time during NtExtendSection() or VirtualAlloc() execution.
*
* THEREFORE LOCAL THREADS SUSPENDING IS ALWAYS REQUIRED!
*/
array_onstack.limit = ARRAY_LENGTH(array_onstack.handles);
array_onstack.count = 0;
suspended = &array_onstack;
rc = mdbx_suspend_threads_before_remap(env, &suspended);
if (rc != MDBX_SUCCESS) {
mdbx_error("failed suspend-for-remap: errcode %d", rc);
goto bailout;
}
#else
/* Acquire guard to avoid collision between read and write txns
* around env->me_dbgeo */
int rc = mdbx_fastmutex_acquire(&env->me_remap_guard);
if (rc != MDBX_SUCCESS)
return rc;
if (limit_bytes == env->me_dxb_mmap.length &&
bytes2pgno(env, size_bytes) == env->me_dbgeo.now)
goto bailout;
#endif /* Windows */
rc = mdbx_mresize(env->me_flags, &env->me_dxb_mmap, size_bytes, limit_bytes);
bailout:
if (rc == MDBX_SUCCESS) {
#if defined(_WIN32) || defined(_WIN64)
mdbx_assert(env, size_bytes == env->me_dxb_mmap.current);
mdbx_assert(env, size_bytes <= env->me_dxb_mmap.filesize);
mdbx_assert(env, limit_bytes == env->me_dxb_mmap.length);
#endif
env->me_dbgeo.now = size_bytes;
env->me_dbgeo.upper = limit_bytes;
if (env->me_txn) {
mdbx_tassert(env->me_txn, size_pgno >= env->me_txn->mt_next_pgno);
env->me_txn->mt_end_pgno = size_pgno;
}
#ifdef USE_VALGRIND
if (prev_mapsize != env->me_mapsize || prev_mapaddr != env->me_map) {
VALGRIND_DISCARD(env->me_valgrind_handle);
env->me_valgrind_handle = 0;
if (env->me_mapsize)
env->me_valgrind_handle =
VALGRIND_CREATE_BLOCK(env->me_map, env->me_mapsize, "mdbx");
}
#endif
} else {
if (rc != MDBX_RESULT_TRUE) {
mdbx_error("failed resize datafile/mapping: "
"present %" PRIuPTR " -> %" PRIuPTR ", "
"limit %" PRIuPTR " -> %" PRIuPTR ", errcode %d",
env->me_dbgeo.now, size_bytes, env->me_dbgeo.upper,
limit_bytes, rc);
} else {
mdbx_notice("unable resize datafile/mapping: "
"present %" PRIuPTR " -> %" PRIuPTR ", "
"limit %" PRIuPTR " -> %" PRIuPTR ", errcode %d",
env->me_dbgeo.now, size_bytes, env->me_dbgeo.upper,
limit_bytes, rc);
}
if (!env->me_dxb_mmap.address) {
env->me_flags |= MDBX_FATAL_ERROR;
if (env->me_txn)
env->me_txn->mt_flags |= MDBX_TXN_ERROR;
rc = MDBX_PANIC;
}
}
#if defined(_WIN32) || defined(_WIN64)
int err = MDBX_SUCCESS;
mdbx_srwlock_ReleaseExclusive(&env->me_remap_guard);
if (suspended) {
err = mdbx_resume_threads_after_remap(suspended);
if (suspended != &array_onstack)
mdbx_free(suspended);
}
#else
int err = mdbx_fastmutex_release(&env->me_remap_guard);
#endif /* Windows */
if (err != MDBX_SUCCESS) {
mdbx_fatal("failed resume-after-remap: errcode %d", err);
return MDBX_PANIC;
}
return rc;
}
/* Allocate page numbers and memory for writing. Maintain me_last_reclaimed,
* me_reclaimed_pglist and mt_next_pgno. Set MDBX_TXN_ERROR on failure.
*
* If there are free pages available from older transactions, they
* are re-used first. Otherwise allocate a new page at mt_next_pgno.
* Do not modify the freedB, just merge freeDB records into me_reclaimed_pglist
* and move me_last_reclaimed to say which records were consumed. Only this
* function can create me_reclaimed_pglist and move
* me_last_reclaimed/mt_next_pgno.
*
* [in] mc cursor A cursor handle identifying the transaction and
* database for which we are allocating.
* [in] num the number of pages to allocate.
* [out] mp Address of the allocated page(s). Requests for multiple pages
* will always be satisfied by a single contiguous chunk of memory.
*
* Returns 0 on success, non-zero on failure.*/
#define MDBX_ALLOC_CACHE 1
#define MDBX_ALLOC_GC 2
#define MDBX_ALLOC_NEW 4
#define MDBX_ALLOC_KICK 8
#define MDBX_ALLOC_ALL \
(MDBX_ALLOC_CACHE | MDBX_ALLOC_GC | MDBX_ALLOC_NEW | MDBX_ALLOC_KICK)
static int mdbx_page_alloc(MDBX_cursor *mc, unsigned num, MDBX_page **mp,
int flags) {
int rc;
MDBX_txn *txn = mc->mc_txn;
MDBX_env *env = txn->mt_env;
MDBX_page *np;
if (likely(flags & MDBX_ALLOC_GC)) {
flags |= env->me_flags & (MDBX_COALESCE | MDBX_LIFORECLAIM);
if (unlikely(mc->mc_flags & C_RECLAIMING)) {
/* If mc is updating the freeDB, then the befree-list cannot play
* catch-up with itself by growing while trying to save it. */
flags &=
~(MDBX_ALLOC_GC | MDBX_ALLOC_KICK | MDBX_COALESCE | MDBX_LIFORECLAIM);
} else if (unlikely(txn->mt_dbs[FREE_DBI].md_entries == 0)) {
/* avoid (recursive) search inside empty tree and while tree is updating,
* https://github.com/leo-yuriev/libmdbx/issues/31 */
flags &= ~MDBX_ALLOC_GC;
}
}
if (likely(flags & MDBX_ALLOC_CACHE)) {
/* If there are any loose pages, just use them */
mdbx_assert(env, mp && num);
if (likely(num == 1 && txn->mt_loose_pages)) {
np = txn->mt_loose_pages;
txn->mt_loose_pages = NEXT_LOOSE_PAGE(np);
txn->mt_loose_count--;
mdbx_debug("db %d use loose page %" PRIaPGNO, DDBI(mc), np->mp_pgno);
ASAN_UNPOISON_MEMORY_REGION(np, env->me_psize);
mdbx_tassert(txn, np->mp_pgno < txn->mt_next_pgno);
mdbx_ensure(env, np->mp_pgno >= NUM_METAS);
*mp = np;
return MDBX_SUCCESS;
}
}
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
pgno_t pgno, *repg_list = env->me_reclaimed_pglist;
unsigned repg_pos = 0, repg_len = repg_list ? MDBX_PNL_SIZE(repg_list) : 0;
txnid_t oldest = 0, last = 0;
const unsigned wanna_range = num - 1;
while (1) { /* oom-kick retry loop */
/* If our dirty list is already full, we can't do anything */
if (unlikely(txn->mt_dirtyroom == 0)) {
rc = MDBX_TXN_FULL;
goto fail;
}
MDBX_cursor recur;
for (MDBX_cursor_op op = MDBX_FIRST;;
op = (flags & MDBX_LIFORECLAIM) ? MDBX_PREV : MDBX_NEXT) {
MDBX_val key, data;
/* Seek a big enough contiguous page range.
* Prefer pages with lower pgno. */
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
if (likely(flags & MDBX_ALLOC_CACHE) && repg_len > wanna_range &&
(!(flags & MDBX_COALESCE) || op == MDBX_FIRST)) {
#if MDBX_PNL_ASCENDING
for (repg_pos = 1; repg_pos <= repg_len - wanna_range; ++repg_pos) {
pgno = repg_list[repg_pos];
if (likely(repg_list[repg_pos + wanna_range - 1] ==
pgno + wanna_range - 1))
goto done;
}
#else
repg_pos = repg_len;
do {
pgno = repg_list[repg_pos];
if (likely(repg_list[repg_pos - wanna_range] == pgno + wanna_range))
goto done;
} while (--repg_pos > wanna_range);
#endif /* MDBX_PNL sort-order */
}
if (op == MDBX_FIRST) { /* 1st iteration, setup cursor, etc */
if (unlikely(!(flags & MDBX_ALLOC_GC)))
break /* reclaiming is prohibited for now */;
/* Prepare to fetch more and coalesce */
oldest = (flags & MDBX_LIFORECLAIM) ? mdbx_find_oldest(txn)
: *env->me_oldest;
rc = mdbx_cursor_init(&recur, txn, FREE_DBI);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
if (flags & MDBX_LIFORECLAIM) {
/* Begin from oldest reader if any */
if (oldest > 2) {
last = oldest - 1;
op = MDBX_SET_RANGE;
}
} else if (env->me_last_reclaimed) {
/* Continue lookup from env->me_last_reclaimed to oldest reader */
last = env->me_last_reclaimed;
op = MDBX_SET_RANGE;
}
key.iov_base = &last;
key.iov_len = sizeof(last);
}
if (!(flags & MDBX_LIFORECLAIM)) {
/* Do not try fetch more if the record will be too recent */
if (op != MDBX_FIRST && ++last >= oldest) {
oldest = mdbx_find_oldest(txn);
if (oldest <= last)
break;
}
}
rc = mdbx_cursor_get(&recur, &key, NULL, op);
if (rc == MDBX_NOTFOUND && (flags & MDBX_LIFORECLAIM)) {
if (op == MDBX_SET_RANGE)
continue;
if (oldest < mdbx_find_oldest(txn)) {
oldest = *env->me_oldest;
last = oldest - 1;
key.iov_base = &last;
key.iov_len = sizeof(last);
op = MDBX_SET_RANGE;
rc = mdbx_cursor_get(&recur, &key, NULL, op);
}
}
if (unlikely(rc)) {
if (rc == MDBX_NOTFOUND)
break;
goto fail;
}
last = *(txnid_t *)key.iov_base;
if (oldest <= last) {
oldest = mdbx_find_oldest(txn);
if (oldest <= last) {
if (flags & MDBX_LIFORECLAIM)
continue;
break;
}
}
if (flags & MDBX_LIFORECLAIM) {
/* skip IDs of records that already reclaimed */
if (txn->mt_lifo_reclaimed) {
unsigned i;
for (i = (unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed); i > 0; --i)
if (txn->mt_lifo_reclaimed[i] == last)
break;
if (i)
continue;
}
}
/* Reading next FreeDB record */
np = recur.mc_pg[recur.mc_top];
MDBX_node *leaf = NODEPTR(np, recur.mc_ki[recur.mc_top]);
if (unlikely((rc = mdbx_node_read(&recur, leaf, &data)) != MDBX_SUCCESS))
goto fail;
if ((flags & MDBX_LIFORECLAIM) && !txn->mt_lifo_reclaimed) {
txn->mt_lifo_reclaimed = mdbx_txl_alloc();
if (unlikely(!txn->mt_lifo_reclaimed)) {
rc = MDBX_ENOMEM;
goto fail;
}
}
/* Append PNL from FreeDB record to me_reclaimed_pglist */
mdbx_cassert(mc, (mc->mc_flags & C_GCFREEZE) == 0);
pgno_t *re_pnl = (pgno_t *)data.iov_base;
mdbx_tassert(txn, data.iov_len >= MDBX_PNL_SIZEOF(re_pnl));
mdbx_tassert(txn, mdbx_pnl_check(re_pnl, false));
repg_pos = MDBX_PNL_SIZE(re_pnl);
if (!repg_list) {
if (unlikely(!(env->me_reclaimed_pglist = repg_list =
mdbx_pnl_alloc(repg_pos)))) {
rc = MDBX_ENOMEM;
goto fail;
}
} else {
if (unlikely(
(rc = mdbx_pnl_need(&env->me_reclaimed_pglist, repg_pos)) != 0))
goto fail;
repg_list = env->me_reclaimed_pglist;
}
/* Remember ID of FreeDB record */
if (flags & MDBX_LIFORECLAIM) {
if ((rc = mdbx_txl_append(&txn->mt_lifo_reclaimed, last)) != 0)
goto fail;
}
env->me_last_reclaimed = last;
if (mdbx_debug_enabled(MDBX_DBG_EXTRA)) {
mdbx_debug_extra("PNL read txn %" PRIaTXN " root %" PRIaPGNO
" num %u, PNL",
last, txn->mt_dbs[FREE_DBI].md_root, repg_pos);
unsigned i;
for (i = repg_pos; i; i--)
mdbx_debug_extra_print(" %" PRIaPGNO, re_pnl[i]);
mdbx_debug_extra_print("\n");
}
/* Merge in descending sorted order */
mdbx_pnl_xmerge(repg_list, re_pnl);
repg_len = MDBX_PNL_SIZE(repg_list);
if (unlikely((flags & MDBX_ALLOC_CACHE) == 0)) {
/* Done for a kick-reclaim mode, actually no page needed */
return MDBX_SUCCESS;
}
mdbx_tassert(txn,
repg_len == 0 || repg_list[repg_len] < txn->mt_next_pgno);
if (repg_len) {
/* Refund suitable pages into "unallocated" space */
pgno_t tail = txn->mt_next_pgno;
pgno_t *const begin = repg_list + 1;
pgno_t *const end = begin + repg_len;
pgno_t *higest;
#if MDBX_PNL_ASCENDING
for (higest = end; --higest >= begin;) {
#else
for (higest = begin; higest < end; ++higest) {
#endif /* MDBX_PNL sort-order */
mdbx_tassert(txn, *higest >= NUM_METAS && *higest < tail);
if (*higest != tail - 1)
break;
tail -= 1;
}
if (tail != txn->mt_next_pgno) {
#if MDBX_PNL_ASCENDING
repg_len = (unsigned)(higest + 1 - begin);
#else
repg_len -= (unsigned)(higest - begin);
for (pgno_t *move = begin; higest < end; ++move, ++higest)
*move = *higest;
#endif /* MDBX_PNL sort-order */
MDBX_PNL_SIZE(repg_list) = repg_len;
mdbx_info("refunded %" PRIaPGNO " pages: %" PRIaPGNO " -> %" PRIaPGNO,
tail - txn->mt_next_pgno, tail, txn->mt_next_pgno);
txn->mt_next_pgno = tail;
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
}
}
/* Don't try to coalesce too much. */
if (unlikely(repg_len > MDBX_DPL_TXNFULL / 4))
break;
if (repg_len /* current size */ >= env->me_maxgc_ov1page ||
repg_pos /* prev size */ >= env->me_maxgc_ov1page / 2)
flags &= ~MDBX_COALESCE;
}
if ((flags & (MDBX_COALESCE | MDBX_ALLOC_CACHE)) ==
(MDBX_COALESCE | MDBX_ALLOC_CACHE) &&
repg_len > wanna_range) {
#if MDBX_PNL_ASCENDING
for (repg_pos = 1; repg_pos <= repg_len - wanna_range; ++repg_pos) {
pgno = repg_list[repg_pos];
if (likely(repg_list[repg_pos + wanna_range - 1] ==
pgno + wanna_range - 1))
goto done;
}
#else
repg_pos = repg_len;
do {
pgno = repg_list[repg_pos];
if (likely(repg_list[repg_pos - wanna_range] == pgno + wanna_range))
goto done;
} while (--repg_pos > wanna_range);
#endif /* MDBX_PNL sort-order */
}
/* Use new pages from the map when nothing suitable in the freeDB */
repg_pos = 0;
pgno = txn->mt_next_pgno;
rc = MDBX_MAP_FULL;
const pgno_t next = pgno_add(pgno, num);
if (likely(next <= txn->mt_end_pgno)) {
rc = MDBX_NOTFOUND;
if (likely(flags & MDBX_ALLOC_NEW))
goto done;
}
const MDBX_meta *head = mdbx_meta_head(env);
if ((flags & MDBX_ALLOC_GC) &&
((flags & MDBX_ALLOC_KICK) || rc == MDBX_MAP_FULL)) {
MDBX_meta *steady = mdbx_meta_steady(env);
if (oldest == mdbx_meta_txnid_stable(env, steady) &&
!META_IS_STEADY(head) && META_IS_STEADY(steady)) {
/* LY: Here an oom was happened:
* - all pages had allocated;
* - reclaiming was stopped at the last steady-sync;
* - the head-sync is weak.
* Now we need make a sync to resume reclaiming. If both
* MDBX_NOSYNC and MDBX_MAPASYNC flags are set, then assume that
* utterly no-sync write mode was requested. In such case
* don't make a steady-sync, but only a legacy-mode checkpoint,
* just for resume reclaiming only, not for data consistency. */
mdbx_debug("kick-gc: head %" PRIaTXN "-%s, tail %" PRIaTXN
"-%s, oldest %" PRIaTXN,
mdbx_meta_txnid_stable(env, head), mdbx_durable_str(head),
mdbx_meta_txnid_stable(env, steady),
mdbx_durable_str(steady), oldest);
const unsigned syncflags = F_ISSET(env->me_flags, MDBX_UTTERLY_NOSYNC)
? env->me_flags
: env->me_flags & MDBX_WRITEMAP;
MDBX_meta meta = *head;
if (mdbx_sync_locked(env, syncflags, &meta) == MDBX_SUCCESS) {
txnid_t snap = mdbx_find_oldest(txn);
if (snap > oldest)
continue;
}
}
if (rc == MDBX_MAP_FULL && oldest < txn->mt_txnid - 1) {
if (mdbx_oomkick(env, oldest) > oldest)
continue;
}
}
if (rc == MDBX_MAP_FULL && next < head->mm_geo.upper) {
mdbx_assert(env, next > txn->mt_end_pgno);
pgno_t aligned = pgno_align2os_pgno(
env, pgno_add(next, head->mm_geo.grow - next % head->mm_geo.grow));
if (aligned > head->mm_geo.upper)
aligned = head->mm_geo.upper;
mdbx_assert(env, aligned > txn->mt_end_pgno);
mdbx_info("try growth datafile to %" PRIaPGNO " pages (+%" PRIaPGNO ")",
aligned, aligned - txn->mt_end_pgno);
rc = mdbx_mapresize(env, aligned, head->mm_geo.upper);
if (rc == MDBX_SUCCESS) {
mdbx_tassert(env->me_txn, txn->mt_end_pgno >= next);
if (!mp)
return rc;
goto done;
}
mdbx_warning("unable growth datafile to %" PRIaPGNO "pages (+%" PRIaPGNO
"), errcode %d",
aligned, aligned - txn->mt_end_pgno, rc);
}
fail:
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
if (mp) {
*mp = NULL;
txn->mt_flags |= MDBX_TXN_ERROR;
}
mdbx_assert(env, rc != MDBX_SUCCESS);
return rc;
}
done:
mdbx_tassert(txn, mp && num);
mdbx_ensure(env, pgno >= NUM_METAS);
if (env->me_flags & MDBX_WRITEMAP) {
np = pgno2page(env, pgno);
/* LY: reset no-access flag from mdbx_kill_page() */
VALGRIND_MAKE_MEM_UNDEFINED(np, pgno2bytes(env, num));
ASAN_UNPOISON_MEMORY_REGION(np, pgno2bytes(env, num));
} else {
if (unlikely(!(np = mdbx_page_malloc(txn, num)))) {
rc = MDBX_ENOMEM;
goto fail;
}
}
if (repg_pos) {
mdbx_cassert(mc, (mc->mc_flags & C_GCFREEZE) == 0);
mdbx_tassert(txn, pgno < txn->mt_next_pgno);
mdbx_tassert(txn, pgno == repg_list[repg_pos]);
/* Cutoff allocated pages from me_reclaimed_pglist */
MDBX_PNL_SIZE(repg_list) = repg_len -= num;
for (unsigned i = repg_pos - num; i < repg_len;)
repg_list[++i] = repg_list[++repg_pos];
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
} else {
txn->mt_next_pgno = pgno + num;
mdbx_assert(env, txn->mt_next_pgno <= txn->mt_end_pgno);
}
if (env->me_flags & MDBX_PAGEPERTURB)
memset(np, 0x71 /* 'q', 113 */, pgno2bytes(env, num));
VALGRIND_MAKE_MEM_UNDEFINED(np, pgno2bytes(env, num));
np->mp_pgno = pgno;
np->mp_leaf2_ksize = 0;
np->mp_flags = 0;
np->mp_pages = num;
rc = mdbx_page_dirty(txn, np);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
*mp = np;
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
return MDBX_SUCCESS;
}
/* Copy the used portions of a non-overflow page.
* [in] dst page to copy into
* [in] src page to copy from
* [in] psize size of a page */
__hot static void mdbx_page_copy(MDBX_page *dst, MDBX_page *src,
unsigned psize) {
STATIC_ASSERT(UINT16_MAX > MAX_PAGESIZE - PAGEHDRSZ);
STATIC_ASSERT(MIN_PAGESIZE > PAGEHDRSZ + NODESIZE * 42);
enum { Align = sizeof(pgno_t) };
indx_t upper = src->mp_upper, lower = src->mp_lower, unused = upper - lower;
/* If page isn't full, just copy the used portion. Adjust
* alignment so memcpy may copy words instead of bytes. */
if ((unused &= -Align) && !IS_LEAF2(src)) {
upper = (upper + PAGEHDRSZ) & -Align;
memcpy(dst, src, (lower + PAGEHDRSZ + (Align - 1)) & -Align);
memcpy((pgno_t *)((char *)dst + upper), (pgno_t *)((char *)src + upper),
psize - upper);
} else {
memcpy(dst, src, psize - unused);
}
}
/* Pull a page off the txn's spill list, if present.
*
* If a page being referenced was spilled to disk in this txn, bring
* it back and make it dirty/writable again.
*
* [in] txn the transaction handle.
* [in] mp the page being referenced. It must not be dirty.
* [out] ret the writable page, if any.
* ret is unchanged if mp wasn't spilled. */
__hot static int __must_check_result mdbx_page_unspill(MDBX_txn *txn,
MDBX_page *mp,
MDBX_page **ret) {
MDBX_env *env = txn->mt_env;
const MDBX_txn *tx2;
unsigned x;
pgno_t pgno = mp->mp_pgno, pn = pgno << 1;
for (tx2 = txn; tx2; tx2 = tx2->mt_parent) {
if (!tx2->mt_spill_pages)
continue;
x = mdbx_pnl_search(tx2->mt_spill_pages, pn);
if (x <= MDBX_PNL_SIZE(tx2->mt_spill_pages) &&
tx2->mt_spill_pages[x] == pn) {
MDBX_page *np;
int num;
if (txn->mt_dirtyroom == 0)
return MDBX_TXN_FULL;
num = IS_OVERFLOW(mp) ? mp->mp_pages : 1;
if (env->me_flags & MDBX_WRITEMAP) {
np = mp;
} else {
np = mdbx_page_malloc(txn, num);
if (unlikely(!np))
return MDBX_ENOMEM;
if (unlikely(num > 1))
memcpy(np, mp, pgno2bytes(env, num));
else
mdbx_page_copy(np, mp, env->me_psize);
}
mdbx_debug("unspill page %" PRIaPGNO, mp->mp_pgno);
if (tx2 == txn) {
/* If in current txn, this page is no longer spilled.
* If it happens to be the last page, truncate the spill list.
* Otherwise mark it as deleted by setting the LSB. */
if (x == MDBX_PNL_SIZE(txn->mt_spill_pages))
MDBX_PNL_SIZE(txn->mt_spill_pages)--;
else
txn->mt_spill_pages[x] |= 1;
} /* otherwise, if belonging to a parent txn, the
* page remains spilled until child commits */
int rc = mdbx_page_dirty(txn, np);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
np->mp_flags |= P_DIRTY;
*ret = np;
break;
}
}
return MDBX_SUCCESS;
}
/* Touch a page: make it dirty and re-insert into tree with updated pgno.
* Set MDBX_TXN_ERROR on failure.
*
* [in] mc cursor pointing to the page to be touched
*
* Returns 0 on success, non-zero on failure. */
__hot static int mdbx_page_touch(MDBX_cursor *mc) {
MDBX_page *mp = mc->mc_pg[mc->mc_top], *np;
MDBX_txn *txn = mc->mc_txn;
MDBX_cursor *m2, *m3;
pgno_t pgno;
int rc;
mdbx_cassert(mc, !IS_OVERFLOW(mp));
if (!F_ISSET(mp->mp_flags, P_DIRTY)) {
if (txn->mt_flags & MDBX_TXN_SPILLS) {
np = NULL;
rc = mdbx_page_unspill(txn, mp, &np);
if (unlikely(rc))
goto fail;
if (likely(np))
goto done;
}
if (unlikely((rc = mdbx_pnl_need(&txn->mt_befree_pages, 1)) ||
(rc = mdbx_page_alloc(mc, 1, &np, MDBX_ALLOC_ALL))))
goto fail;
pgno = np->mp_pgno;
mdbx_debug("touched db %d page %" PRIaPGNO " -> %" PRIaPGNO, DDBI(mc),
mp->mp_pgno, pgno);
mdbx_cassert(mc, mp->mp_pgno != pgno);
mdbx_pnl_xappend(txn->mt_befree_pages, mp->mp_pgno);
/* Update the parent page, if any, to point to the new page */
if (mc->mc_top) {
MDBX_page *parent = mc->mc_pg[mc->mc_top - 1];
MDBX_node *node = NODEPTR(parent, mc->mc_ki[mc->mc_top - 1]);
SETPGNO(node, pgno);
} else {
mc->mc_db->md_root = pgno;
}
} else if (txn->mt_parent && !IS_SUBP(mp)) {
mdbx_tassert(txn, (txn->mt_env->me_flags & MDBX_WRITEMAP) == 0);
MDBX_DP *dl = txn->mt_rw_dirtylist;
pgno = mp->mp_pgno;
/* If txn has a parent, make sure the page is in our dirty list. */
if (dl->length) {
unsigned x = mdbx_dpl_search(dl, pgno);
if (x <= dl->length && dl[x].pgno == pgno) {
if (unlikely(mp != dl[x].ptr)) { /* bad cursor? */
mdbx_error("wrong page 0x%p #%" PRIaPGNO
" in the dirtylist[%d], expecting %p",
dl[x].ptr, pgno, x, mp);
mc->mc_flags &= ~(C_INITIALIZED | C_EOF);
rc = MDBX_PROBLEM;
goto fail;
}
return MDBX_SUCCESS;
}
}
mdbx_debug("clone db %d page %" PRIaPGNO, DDBI(mc), mp->mp_pgno);
mdbx_cassert(mc, dl->length <= MDBX_DPL_TXNFULL);
/* No - copy it */
np = mdbx_page_malloc(txn, 1);
if (unlikely(!np)) {
rc = MDBX_ENOMEM;
goto fail;
}
rc = mdbx_dpl_insert(dl, pgno, np);
if (unlikely(rc)) {
mdbx_dpage_free(txn->mt_env, np, 1);
goto fail;
}
} else {
return MDBX_SUCCESS;
}
mdbx_page_copy(np, mp, txn->mt_env->me_psize);
np->mp_pgno = pgno;
np->mp_flags |= P_DIRTY;
done:
/* Adjust cursors pointing to mp */
mc->mc_pg[mc->mc_top] = np;
m2 = txn->mt_cursors[mc->mc_dbi];
if (mc->mc_flags & C_SUB) {
for (; m2; m2 = m2->mc_next) {
m3 = &m2->mc_xcursor->mx_cursor;
if (m3->mc_snum < mc->mc_snum)
continue;
if (m3->mc_pg[mc->mc_top] == mp)
m3->mc_pg[mc->mc_top] = np;
}
} else {
for (; m2; m2 = m2->mc_next) {
if (m2->mc_snum < mc->mc_snum)
continue;
if (m2 == mc)
continue;
if (m2->mc_pg[mc->mc_top] == mp) {
m2->mc_pg[mc->mc_top] = np;
if (XCURSOR_INITED(m2) && IS_LEAF(np))
XCURSOR_REFRESH(m2, np, m2->mc_ki[mc->mc_top]);
}
}
}
return MDBX_SUCCESS;
fail:
txn->mt_flags |= MDBX_TXN_ERROR;
return rc;
}
__cold static int mdbx_env_sync_ex(MDBX_env *env, int force, int nonblock) {
if (unlikely(!env))
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
unsigned flags = env->me_flags & ~MDBX_NOMETASYNC;
if (unlikely(flags & (MDBX_RDONLY | MDBX_FATAL_ERROR)))
return MDBX_EACCESS;
const bool outside_txn =
(!env->me_txn0 || env->me_txn0->mt_owner != mdbx_thread_self());
if (outside_txn) {
int rc = mdbx_txn_lock(env, nonblock);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
MDBX_meta *head = mdbx_meta_head(env);
if (!META_IS_STEADY(head) || env->me_sync_pending) {
if (force || (env->me_sync_threshold &&
env->me_sync_pending >= env->me_sync_threshold))
flags &= MDBX_WRITEMAP /* clear flags for full steady sync */;
if (outside_txn &&
env->me_sync_pending >
pgno2bytes(env, 16 /* FIXME: define threshold */) &&
(flags & MDBX_NOSYNC) == 0) {
mdbx_assert(env, ((flags ^ env->me_flags) & MDBX_WRITEMAP) == 0);
const size_t usedbytes = pgno_align2os_bytes(env, head->mm_geo.next);
mdbx_txn_unlock(env);
/* LY: pre-sync without holding lock to reduce latency for writer(s) */
int rc = (flags & MDBX_WRITEMAP)
? mdbx_msync(&env->me_dxb_mmap, 0, usedbytes,
flags & MDBX_MAPASYNC)
: mdbx_filesync(env->me_fd, false);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
rc = mdbx_txn_lock(env, nonblock);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
/* LY: head may be changed. */
head = mdbx_meta_head(env);
}
if (!META_IS_STEADY(head) || env->me_sync_pending) {
mdbx_debug("meta-head %" PRIaPGNO ", %s, sync_pending %" PRIuPTR,
container_of(head, MDBX_page, mp_data)->mp_pgno,
mdbx_durable_str(head), env->me_sync_pending);
MDBX_meta meta = *head;
int rc = mdbx_sync_locked(env, flags | MDBX_SHRINK_ALLOWED, &meta);
if (unlikely(rc != MDBX_SUCCESS)) {
if (outside_txn)
mdbx_txn_unlock(env);
return rc;
}
}
}
if (outside_txn)
mdbx_txn_unlock(env);
return MDBX_SUCCESS;
}
__cold int mdbx_env_sync(MDBX_env *env, int force) {
return mdbx_env_sync_ex(env, force, false);
}
/* Back up parent txn's cursors, then grab the originals for tracking */
static int mdbx_cursor_shadow(MDBX_txn *src, MDBX_txn *dst) {
MDBX_cursor *mc, *bk;
MDBX_xcursor *mx;
size_t size;
int i;
for (i = src->mt_numdbs; --i >= 0;) {
if ((mc = src->mt_cursors[i]) != NULL) {
size = sizeof(MDBX_cursor);
if (mc->mc_xcursor)
size += sizeof(MDBX_xcursor);
for (; mc; mc = bk->mc_next) {
bk = mdbx_malloc(size);
if (unlikely(!bk))
return MDBX_ENOMEM;
*bk = *mc;
mc->mc_backup = bk;
mc->mc_db = &dst->mt_dbs[i];
/* Kill pointers into src to reduce abuse: The
* user may not use mc until dst ends. But we need a valid
* txn pointer here for cursor fixups to keep working. */
mc->mc_txn = dst;
mc->mc_dbflag = &dst->mt_dbflags[i];
if ((mx = mc->mc_xcursor) != NULL) {
*(MDBX_xcursor *)(bk + 1) = *mx;
mx->mx_cursor.mc_txn = dst;
}
mc->mc_next = dst->mt_cursors[i];
dst->mt_cursors[i] = mc;
}
}
}
return MDBX_SUCCESS;
}
/* Close this write txn's cursors, give parent txn's cursors back to parent.
*
* [in] txn the transaction handle.
* [in] merge true to keep changes to parent cursors, false to revert.
*
* Returns 0 on success, non-zero on failure. */
static void mdbx_cursors_eot(MDBX_txn *txn, unsigned merge) {
MDBX_cursor **cursors = txn->mt_cursors, *mc, *next, *bk;
MDBX_xcursor *mx;
int i;
for (i = txn->mt_numdbs; --i >= 0;) {
for (mc = cursors[i]; mc; mc = next) {
unsigned stage = mc->mc_signature;
mdbx_ensure(NULL,
stage == MDBX_MC_SIGNATURE || stage == MDBX_MC_WAIT4EOT);
next = mc->mc_next;
if ((bk = mc->mc_backup) != NULL) {
if (merge) {
/* Commit changes to parent txn */
mc->mc_next = bk->mc_next;
mc->mc_backup = bk->mc_backup;
mc->mc_txn = bk->mc_txn;
mc->mc_db = bk->mc_db;
mc->mc_dbflag = bk->mc_dbflag;
if ((mx = mc->mc_xcursor) != NULL)
mx->mx_cursor.mc_txn = bk->mc_txn;
} else {
/* Abort nested txn */
*mc = *bk;
if ((mx = mc->mc_xcursor) != NULL)
*mx = *(MDBX_xcursor *)(bk + 1);
}
bk->mc_signature = 0;
mdbx_free(bk);
}
if (stage == MDBX_MC_WAIT4EOT) {
mc->mc_signature = 0;
mdbx_free(mc);
} else {
mc->mc_signature = MDBX_MC_READY4CLOSE;
mc->mc_flags = 0 /* reset C_UNTRACK */;
}
}
cursors[i] = NULL;
}
}
/* Common code for mdbx_txn_begin() and mdbx_txn_renew(). */
static int mdbx_txn_renew0(MDBX_txn *txn, unsigned flags) {
MDBX_env *env = txn->mt_env;
int rc;
if (unlikely(env->me_pid != mdbx_getpid())) {
env->me_flags |= MDBX_FATAL_ERROR;
return MDBX_PANIC;
}
STATIC_ASSERT(sizeof(MDBX_reader) == MDBX_CACHELINE_SIZE);
STATIC_ASSERT(offsetof(MDBX_lockinfo, mti_numreaders) % MDBX_CACHELINE_SIZE ==
0);
STATIC_ASSERT(offsetof(MDBX_lockinfo, mti_readers) % MDBX_CACHELINE_SIZE ==
0);
pgno_t upper_pgno = 0;
if (flags & MDBX_TXN_RDONLY) {
txn->mt_flags = MDBX_TXN_RDONLY;
MDBX_reader *r = txn->mt_ro_reader;
if (likely(env->me_flags & MDBX_ENV_TXKEY)) {
mdbx_assert(env, !(env->me_flags & MDBX_NOTLS));
r = mdbx_thread_rthc_get(env->me_txkey);
if (likely(r)) {
mdbx_assert(env, r->mr_pid == env->me_pid);
mdbx_assert(env, r->mr_tid == mdbx_thread_self());
}
} else {
mdbx_assert(env, !env->me_lck || (env->me_flags & MDBX_NOTLS));
}
if (likely(r)) {
if (unlikely(r->mr_pid != env->me_pid || r->mr_txnid != ~(txnid_t)0))
return MDBX_BAD_RSLOT;
} else if (env->me_lck) {
unsigned slot, nreaders;
const mdbx_tid_t tid = mdbx_thread_self();
mdbx_assert(env, env->me_lck->mti_magic_and_version == MDBX_LOCK_MAGIC);
mdbx_assert(env, env->me_lck->mti_os_and_format == MDBX_LOCK_FORMAT);
rc = mdbx_rdt_lock(env);
if (unlikely(MDBX_IS_ERROR(rc)))
return rc;
if (unlikely(env->me_flags & MDBX_FATAL_ERROR)) {
mdbx_rdt_unlock(env);
return MDBX_PANIC;
}
#if defined(_WIN32) || defined(_WIN64)
if (unlikely(!env->me_map)) {
mdbx_rdt_unlock(env);
return MDBX_EPERM;
}
#endif /* Windows */
rc = MDBX_SUCCESS;
if (unlikely(env->me_live_reader != env->me_pid)) {
rc = mdbx_rpid_set(env);
if (unlikely(rc != MDBX_SUCCESS)) {
mdbx_rdt_unlock(env);
return rc;
}
env->me_live_reader = env->me_pid;
}
while (1) {
nreaders = env->me_lck->mti_numreaders;
for (slot = 0; slot < nreaders; slot++)
if (env->me_lck->mti_readers[slot].mr_pid == 0)
break;
if (likely(slot < env->me_maxreaders))
break;
rc = mdbx_reader_check0(env, true, NULL);
if (rc != MDBX_RESULT_TRUE) {
mdbx_rdt_unlock(env);
return (rc == MDBX_SUCCESS) ? MDBX_READERS_FULL : rc;
}
}
r = &env->me_lck->mti_readers[slot];
/* Claim the reader slot, carefully since other code
* uses the reader table un-mutexed: First reset the
* slot, next publish it in mtb.mti_numreaders. After
* that, it is safe for mdbx_env_close() to touch it.
* When it will be closed, we can finally claim it. */
r->mr_pid = 0;
r->mr_txnid = ~(txnid_t)0;
r->mr_tid = tid;
mdbx_coherent_barrier();
if (slot == nreaders)
env->me_lck->mti_numreaders = ++nreaders;
if (env->me_close_readers < nreaders)
env->me_close_readers = nreaders;
r->mr_pid = env->me_pid;
mdbx_rdt_unlock(env);
if (likely(env->me_flags & MDBX_ENV_TXKEY)) {
mdbx_assert(env, env->me_live_reader == env->me_pid);
mdbx_thread_rthc_set(env->me_txkey, r);
}
}
while (1) {
MDBX_meta *const meta = mdbx_meta_head(env);
mdbx_jitter4testing(false);
const txnid_t snap = mdbx_meta_txnid_fluid(env, meta);
mdbx_jitter4testing(false);
if (r) {
r->mr_txnid = snap;
mdbx_jitter4testing(false);
mdbx_assert(env, r->mr_pid == mdbx_getpid());
mdbx_assert(env, r->mr_tid == mdbx_thread_self());
mdbx_assert(env, r->mr_txnid == snap);
mdbx_coherent_barrier();
env->me_lck->mti_readers_refresh_flag = true;
}
mdbx_jitter4testing(true);
/* Snap the state from current meta-head */
txn->mt_txnid = snap;
txn->mt_next_pgno = meta->mm_geo.next;
txn->mt_end_pgno = meta->mm_geo.now;
upper_pgno = meta->mm_geo.upper;
memcpy(txn->mt_dbs, meta->mm_dbs, CORE_DBS * sizeof(MDBX_db));
txn->mt_canary = meta->mm_canary;
/* LY: Retry on a race, ITS#7970. */
mdbx_compiler_barrier();
if (likely(meta == mdbx_meta_head(env) &&
snap == mdbx_meta_txnid_fluid(env, meta) &&
snap >= *env->me_oldest)) {
mdbx_jitter4testing(false);
break;
}
}
if (unlikely(txn->mt_txnid == 0)) {
mdbx_error("environment corrupted by died writer, must shutdown!");
rc = MDBX_WANNA_RECOVERY;
goto bailout;
}
mdbx_assert(env, txn->mt_txnid >= *env->me_oldest);
txn->mt_ro_reader = r;
txn->mt_dbxs = env->me_dbxs; /* mostly static anyway */
} else {
/* Not yet touching txn == env->me_txn0, it may be active */
mdbx_jitter4testing(false);
rc = mdbx_txn_lock(env, F_ISSET(flags, MDBX_TRYTXN));
if (unlikely(rc))
return rc;
if (unlikely(env->me_flags & MDBX_FATAL_ERROR)) {
mdbx_txn_unlock(env);
return MDBX_PANIC;
}
#if defined(_WIN32) || defined(_WIN64)
if (unlikely(!env->me_map)) {
mdbx_txn_unlock(env);
return MDBX_EPERM;
}
#endif /* Windows */
mdbx_jitter4testing(false);
MDBX_meta *meta = mdbx_meta_head(env);
mdbx_jitter4testing(false);
txn->mt_canary = meta->mm_canary;
const txnid_t snap = mdbx_meta_txnid_stable(env, meta);
txn->mt_txnid = snap + 1;
if (unlikely(txn->mt_txnid < snap)) {
mdbx_debug("txnid overflow!");
rc = MDBX_TXN_FULL;
goto bailout;
}
txn->mt_flags = flags;
txn->mt_child = NULL;
txn->mt_loose_pages = NULL;
txn->mt_loose_count = 0;
txn->mt_dirtyroom = MDBX_DPL_TXNFULL;
txn->mt_rw_dirtylist = env->me_dirtylist;
txn->mt_rw_dirtylist->length = 0;
txn->mt_befree_pages = env->me_free_pgs;
MDBX_PNL_SIZE(txn->mt_befree_pages) = 0;
txn->mt_spill_pages = NULL;
if (txn->mt_lifo_reclaimed)
MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) = 0;
env->me_txn = txn;
memcpy(txn->mt_dbiseqs, env->me_dbiseqs, env->me_maxdbs * sizeof(unsigned));
/* Copy the DB info and flags */
memcpy(txn->mt_dbs, meta->mm_dbs, CORE_DBS * sizeof(MDBX_db));
/* Moved to here to avoid a data race in read TXNs */
txn->mt_next_pgno = meta->mm_geo.next;
txn->mt_end_pgno = meta->mm_geo.now;
upper_pgno = meta->mm_geo.upper;
}
/* Setup db info */
txn->mt_numdbs = env->me_numdbs;
mdbx_compiler_barrier();
for (unsigned i = CORE_DBS; i < txn->mt_numdbs; i++) {
unsigned x = env->me_dbflags[i];
txn->mt_dbs[i].md_flags = x & PERSISTENT_FLAGS;
txn->mt_dbflags[i] =
(x & MDBX_VALID) ? DB_VALID | DB_USRVALID | DB_STALE : 0;
}
txn->mt_dbflags[MAIN_DBI] = DB_VALID | DB_USRVALID;
txn->mt_dbflags[FREE_DBI] = DB_VALID;
if (unlikely(env->me_flags & MDBX_FATAL_ERROR)) {
mdbx_warning("environment had fatal error, must shutdown!");
rc = MDBX_PANIC;
} else {
const size_t size = pgno2bytes(env, txn->mt_end_pgno);
if (unlikely(size > env->me_mapsize)) {
if (upper_pgno > MAX_PAGENO ||
bytes2pgno(env, pgno2bytes(env, upper_pgno)) != upper_pgno) {
rc = MDBX_MAP_RESIZED;
goto bailout;
}
rc = mdbx_mapresize(env, txn->mt_end_pgno, upper_pgno);
if (rc != MDBX_SUCCESS) {
if (rc == MDBX_RESULT_TRUE)
rc = MDBX_MAP_RESIZED;
goto bailout;
}
}
txn->mt_owner = mdbx_thread_self();
#if defined(_WIN32) || defined(_WIN64)
if ((txn->mt_flags & MDBX_TXN_RDONLY) != 0 && size > env->me_dbgeo.lower &&
env->me_dbgeo.shrink) {
txn->mt_flags |= MDBX_SHRINK_ALLOWED;
mdbx_srwlock_AcquireShared(&env->me_remap_guard);
}
#endif
return MDBX_SUCCESS;
}
bailout:
mdbx_tassert(txn, rc != MDBX_SUCCESS);
mdbx_txn_end(txn, MDBX_END_SLOT | MDBX_END_FAIL_BEGIN);
return rc;
}
int mdbx_txn_renew(MDBX_txn *txn) {
int rc;
if (unlikely(!txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely((txn->mt_flags & MDBX_TXN_RDONLY) == 0))
return MDBX_EINVAL;
if (unlikely(txn->mt_owner != 0))
return MDBX_THREAD_MISMATCH;
rc = mdbx_txn_renew0(txn, MDBX_TXN_RDONLY);
if (rc == MDBX_SUCCESS) {
txn->mt_owner = mdbx_thread_self();
mdbx_debug("renew txn %" PRIaTXN "%c %p on env %p, root page %" PRIaPGNO
"/%" PRIaPGNO,
txn->mt_txnid, (txn->mt_flags & MDBX_TXN_RDONLY) ? 'r' : 'w',
(void *)txn, (void *)txn->mt_env, txn->mt_dbs[MAIN_DBI].md_root,
txn->mt_dbs[FREE_DBI].md_root);
}
return rc;
}
int mdbx_txn_begin(MDBX_env *env, MDBX_txn *parent, unsigned flags,
MDBX_txn **ret) {
MDBX_txn *txn;
MDBX_ntxn *ntxn;
int rc;
unsigned size, tsize;
if (unlikely(!env || !ret))
return MDBX_EINVAL;
*ret = NULL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(env->me_pid != mdbx_getpid()))
env->me_flags |= MDBX_FATAL_ERROR;
if (unlikely(env->me_flags & MDBX_FATAL_ERROR))
return MDBX_PANIC;
#if !defined(_WIN32) && !defined(_WIN64)
/* Don't check env->me_map until lock to avoid race with re-mapping for
* shrinking */
if (unlikely(!env->me_map))
return MDBX_EPERM;
#endif /* Windows */
flags &= MDBX_TXN_BEGIN_FLAGS;
flags |= env->me_flags & MDBX_WRITEMAP;
if (unlikely(env->me_flags & MDBX_RDONLY &
~flags)) /* write txn in RDONLY env */
return MDBX_EACCESS;
if (parent) {
if (unlikely(parent->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(parent->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
#if defined(_WIN32) || defined(_WIN64)
if (unlikely(!env->me_map))
return MDBX_EPERM;
#endif /* Windows */
/* Nested transactions: Max 1 child, write txns only, no writemap */
flags |= parent->mt_flags;
if (unlikely(flags & (MDBX_RDONLY | MDBX_WRITEMAP | MDBX_TXN_BLOCKED)))
return (parent->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EINVAL : MDBX_BAD_TXN;
/* Child txns save MDBX_pgstate and use own copy of cursors */
size = env->me_maxdbs * (sizeof(MDBX_db) + sizeof(MDBX_cursor *) + 1);
size += tsize = sizeof(MDBX_ntxn);
} else if (flags & MDBX_RDONLY) {
if (env->me_txn0 && unlikely(env->me_txn0->mt_owner == mdbx_thread_self()))
return MDBX_BUSY;
size = env->me_maxdbs * (sizeof(MDBX_db) + 1);
size += tsize = sizeof(MDBX_txn);
} else {
/* Reuse preallocated write txn. However, do not touch it until
* mdbx_txn_renew0() succeeds, since it currently may be active. */
txn = env->me_txn0;
if (unlikely(txn->mt_owner == mdbx_thread_self()))
return MDBX_BUSY;
goto renew;
}
if (unlikely((txn = mdbx_malloc(size)) == NULL)) {
mdbx_debug("calloc: %s", "failed");
return MDBX_ENOMEM;
}
memset(txn, 0, tsize);
txn->mt_dbxs = env->me_dbxs; /* static */
txn->mt_dbs = (MDBX_db *)((char *)txn + tsize);
txn->mt_dbflags = (uint8_t *)txn + size - env->me_maxdbs;
txn->mt_flags = flags;
txn->mt_env = env;
if (parent) {
unsigned i;
txn->mt_cursors = (MDBX_cursor **)(txn->mt_dbs + env->me_maxdbs);
txn->mt_dbiseqs = parent->mt_dbiseqs;
txn->mt_rw_dirtylist =
mdbx_malloc(sizeof(MDBX_DP) * (MDBX_DPL_TXNFULL + 1));
if (!txn->mt_rw_dirtylist ||
!(txn->mt_befree_pages = mdbx_pnl_alloc(MDBX_PNL_INITIAL))) {
mdbx_free(txn->mt_rw_dirtylist);
mdbx_free(txn);
return MDBX_ENOMEM;
}
txn->mt_txnid = parent->mt_txnid;
txn->mt_dirtyroom = parent->mt_dirtyroom;
txn->mt_rw_dirtylist->length = 0;
txn->mt_spill_pages = NULL;
txn->mt_next_pgno = parent->mt_next_pgno;
txn->mt_end_pgno = parent->mt_end_pgno;
parent->mt_flags |= MDBX_TXN_HAS_CHILD;
parent->mt_child = txn;
txn->mt_parent = parent;
txn->mt_numdbs = parent->mt_numdbs;
memcpy(txn->mt_dbs, parent->mt_dbs, txn->mt_numdbs * sizeof(MDBX_db));
/* Copy parent's mt_dbflags, but clear DB_NEW */
for (i = 0; i < txn->mt_numdbs; i++)
txn->mt_dbflags[i] = parent->mt_dbflags[i] & ~(DB_FRESH | DB_CREAT);
rc = 0;
ntxn = (MDBX_ntxn *)txn;
ntxn->mnt_pgstate =
env->me_pgstate; /* save parent me_reclaimed_pglist & co */
if (env->me_reclaimed_pglist) {
size = MDBX_PNL_SIZEOF(env->me_reclaimed_pglist);
env->me_reclaimed_pglist =
mdbx_pnl_alloc(MDBX_PNL_SIZE(env->me_reclaimed_pglist));
if (likely(env->me_reclaimed_pglist))
memcpy(env->me_reclaimed_pglist, ntxn->mnt_pgstate.mf_reclaimed_pglist,
size);
else
rc = MDBX_ENOMEM;
}
if (likely(!rc))
rc = mdbx_cursor_shadow(parent, txn);
if (unlikely(rc))
mdbx_txn_end(txn, MDBX_END_FAIL_BEGINCHILD);
} else { /* MDBX_RDONLY */
txn->mt_dbiseqs = env->me_dbiseqs;
renew:
rc = mdbx_txn_renew0(txn, flags);
}
if (unlikely(rc != MDBX_SUCCESS)) {
if (txn != env->me_txn0)
mdbx_free(txn);
} else {
mdbx_assert(env, (txn->mt_flags & ~(MDBX_TXN_RDONLY | MDBX_TXN_WRITEMAP |
MDBX_SHRINK_ALLOWED)) == 0);
txn->mt_signature = MDBX_MT_SIGNATURE;
*ret = txn;
mdbx_debug("begin txn %" PRIaTXN "%c %p on env %p, root page %" PRIaPGNO
"/%" PRIaPGNO,
txn->mt_txnid, (flags & MDBX_RDONLY) ? 'r' : 'w', (void *)txn,
(void *)env, txn->mt_dbs[MAIN_DBI].md_root,
txn->mt_dbs[FREE_DBI].md_root);
}
return rc;
}
MDBX_env *mdbx_txn_env(MDBX_txn *txn) {
if (unlikely(!txn || txn->mt_signature != MDBX_MT_SIGNATURE))
return NULL;
return txn->mt_env;
}
uint64_t mdbx_txn_id(MDBX_txn *txn) {
if (unlikely(!txn || txn->mt_signature != MDBX_MT_SIGNATURE))
return ~(txnid_t)0;
return txn->mt_txnid;
}
int mdbx_txn_flags(MDBX_txn *txn) {
if (unlikely(!txn || txn->mt_signature != MDBX_MT_SIGNATURE))
return -1;
return txn->mt_flags;
}
/* Export or close DBI handles opened in this txn. */
static void mdbx_dbis_update(MDBX_txn *txn, int keep) {
MDBX_dbi n = txn->mt_numdbs;
if (n) {
bool locked = false;
MDBX_env *env = txn->mt_env;
uint8_t *tdbflags = txn->mt_dbflags;
for (unsigned i = n; --i >= CORE_DBS;) {
if (likely((tdbflags[i] & DB_CREAT) == 0))
continue;
if (!locked) {
mdbx_ensure(env,
mdbx_fastmutex_acquire(&env->me_dbi_lock) == MDBX_SUCCESS);
locked = true;
}
if (keep) {
env->me_dbflags[i] = txn->mt_dbs[i].md_flags | MDBX_VALID;
mdbx_compiler_barrier();
if (env->me_numdbs <= i)
env->me_numdbs = i + 1;
} else {
char *ptr = env->me_dbxs[i].md_name.iov_base;
if (ptr) {
env->me_dbxs[i].md_name.iov_len = 0;
mdbx_compiler_barrier();
mdbx_assert(env, env->me_dbflags[i] == 0);
env->me_dbiseqs[i]++;
env->me_dbxs[i].md_name.iov_base = NULL;
mdbx_free(ptr);
}
}
}
if (unlikely(locked))
mdbx_ensure(env,
mdbx_fastmutex_release(&env->me_dbi_lock) == MDBX_SUCCESS);
}
}
/* End a transaction, except successful commit of a nested transaction.
* May be called twice for readonly txns: First reset it, then abort.
* [in] txn the transaction handle to end
* [in] mode why and how to end the transaction */
static int mdbx_txn_end(MDBX_txn *txn, unsigned mode) {
MDBX_env *env = txn->mt_env;
static const char *const names[] = MDBX_END_NAMES;
if (unlikely(txn->mt_env->me_pid != mdbx_getpid())) {
env->me_flags |= MDBX_FATAL_ERROR;
return MDBX_PANIC;
}
mdbx_debug("%s txn %" PRIaTXN "%c %p on mdbenv %p, root page %" PRIaPGNO
"/%" PRIaPGNO,
names[mode & MDBX_END_OPMASK], txn->mt_txnid,
(txn->mt_flags & MDBX_TXN_RDONLY) ? 'r' : 'w', (void *)txn,
(void *)env, txn->mt_dbs[MAIN_DBI].md_root,
txn->mt_dbs[FREE_DBI].md_root);
if (F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY)) {
#if defined(_WIN32) || defined(_WIN64)
if (txn->mt_flags & MDBX_SHRINK_ALLOWED)
mdbx_srwlock_ReleaseShared(&env->me_remap_guard);
#endif
if (txn->mt_ro_reader) {
txn->mt_ro_reader->mr_txnid = ~(txnid_t)0;
env->me_lck->mti_readers_refresh_flag = true;
if (mode & MDBX_END_SLOT) {
if ((env->me_flags & MDBX_ENV_TXKEY) == 0)
txn->mt_ro_reader->mr_pid = 0;
txn->mt_ro_reader = NULL;
}
}
mdbx_coherent_barrier();
txn->mt_numdbs = 0; /* prevent further DBI activity */
txn->mt_flags = MDBX_TXN_RDONLY | MDBX_TXN_FINISHED;
txn->mt_owner = 0;
} else if (!F_ISSET(txn->mt_flags, MDBX_TXN_FINISHED)) {
/* Export or close DBI handles created in this txn */
mdbx_dbis_update(txn, mode & MDBX_END_UPDATE);
pgno_t *pghead = env->me_reclaimed_pglist;
if (!(mode & MDBX_END_EOTDONE)) /* !(already closed cursors) */
mdbx_cursors_eot(txn, 0);
if (!(env->me_flags & MDBX_WRITEMAP)) {
mdbx_dlist_free(txn);
}
if (txn->mt_lifo_reclaimed) {
MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) = 0;
if (txn != env->me_txn0) {
mdbx_txl_free(txn->mt_lifo_reclaimed);
txn->mt_lifo_reclaimed = NULL;
}
}
txn->mt_numdbs = 0;
txn->mt_flags = MDBX_TXN_FINISHED;
txn->mt_owner = 0;
if (!txn->mt_parent) {
mdbx_pnl_shrink(&txn->mt_befree_pages);
env->me_free_pgs = txn->mt_befree_pages;
/* me_pgstate: */
env->me_reclaimed_pglist = NULL;
env->me_last_reclaimed = 0;
env->me_txn = NULL;
/* The writer mutex was locked in mdbx_txn_begin. */
mdbx_txn_unlock(env);
} else {
txn->mt_parent->mt_child = NULL;
txn->mt_parent->mt_flags &= ~MDBX_TXN_HAS_CHILD;
env->me_pgstate = ((MDBX_ntxn *)txn)->mnt_pgstate;
mdbx_pnl_free(txn->mt_befree_pages);
mdbx_pnl_free(txn->mt_spill_pages);
mdbx_free(txn->mt_rw_dirtylist);
}
mdbx_pnl_free(pghead);
}
mdbx_assert(env, txn == env->me_txn0 || txn->mt_owner == 0);
if ((mode & MDBX_END_FREE) != 0 && txn != env->me_txn0) {
txn->mt_signature = 0;
mdbx_free(txn);
}
return MDBX_SUCCESS;
}
int mdbx_txn_reset(MDBX_txn *txn) {
if (unlikely(!txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
/* This call is only valid for read-only txns */
if (unlikely(!(txn->mt_flags & MDBX_TXN_RDONLY)))
return MDBX_EINVAL;
/* LY: don't close DBI-handles in MDBX mode */
int rc = mdbx_txn_end(txn, MDBX_END_RESET | MDBX_END_UPDATE);
if (rc == MDBX_SUCCESS) {
mdbx_tassert(txn, txn->mt_signature == MDBX_MT_SIGNATURE);
mdbx_tassert(txn, txn->mt_owner == 0);
}
return rc;
}
int mdbx_txn_abort(MDBX_txn *txn) {
if (unlikely(!txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY))
/* LY: don't close DBI-handles in MDBX mode */
return mdbx_txn_end(txn, MDBX_END_ABORT | MDBX_END_UPDATE | MDBX_END_SLOT |
MDBX_END_FREE);
if (txn->mt_child)
mdbx_txn_abort(txn->mt_child);
return mdbx_txn_end(txn, MDBX_END_ABORT | MDBX_END_SLOT | MDBX_END_FREE);
}
static __inline int mdbx_backlog_size(MDBX_txn *txn) {
int reclaimed_and_loose =
txn->mt_env->me_reclaimed_pglist
? MDBX_PNL_SIZE(txn->mt_env->me_reclaimed_pglist) +
txn->mt_loose_count
: 0;
return reclaimed_and_loose + txn->mt_end_pgno - txn->mt_next_pgno;
}
static __inline int mdbx_backlog_extragap(MDBX_env *env) {
/* LY: extra page(s) for b-tree rebalancing */
return (env->me_flags & MDBX_LIFORECLAIM) ? 2 : 1;
}
/* LY: Prepare a backlog of pages to modify FreeDB itself,
* while reclaiming is prohibited. It should be enough to prevent search
* in mdbx_page_alloc() during a deleting, when freeDB tree is unbalanced. */
static int mdbx_prep_backlog(MDBX_txn *txn, MDBX_cursor *mc) {
/* LY: extra page(s) for b-tree rebalancing */
const int extra = mdbx_backlog_extragap(txn->mt_env);
if (mdbx_backlog_size(txn) < mc->mc_db->md_depth + extra) {
int rc = mdbx_cursor_touch(mc);
if (unlikely(rc))
return rc;
int backlog;
while (unlikely((backlog = mdbx_backlog_size(txn)) < extra)) {
rc = mdbx_page_alloc(mc, 1, NULL, MDBX_ALLOC_GC);
if (unlikely(rc)) {
if (unlikely(rc != MDBX_NOTFOUND))
return rc;
break;
}
}
}
return MDBX_SUCCESS;
}
/* Count all the pages in each DB and in the freelist and make sure
* it matches the actual number of pages being used.
* All named DBs must be open for a correct count. */
static __cold int mdbx_audit(MDBX_txn *txn, unsigned befree_stored) {
MDBX_val key, data;
const pgno_t pending =
(txn->mt_flags & MDBX_RDONLY)
? 0
: txn->mt_loose_count +
(txn->mt_env->me_reclaimed_pglist
? MDBX_PNL_SIZE(txn->mt_env->me_reclaimed_pglist)
: 0) +
(txn->mt_befree_pages
? MDBX_PNL_SIZE(txn->mt_befree_pages) - befree_stored
: 0);
MDBX_cursor_couple cx;
int rc = mdbx_cursor_init(&cx.outer, txn, FREE_DBI);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
pgno_t freecount = 0;
while ((rc = mdbx_cursor_get(&cx.outer, &key, &data, MDBX_NEXT)) == 0)
freecount += *(pgno_t *)data.iov_base;
mdbx_tassert(txn, rc == MDBX_NOTFOUND);
pgno_t count = 0;
for (MDBX_dbi i = FREE_DBI; i <= MAIN_DBI; i++) {
if (!(txn->mt_dbflags[i] & DB_VALID))
continue;
rc = mdbx_cursor_init(&cx.outer, txn, i);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
if (txn->mt_dbs[i].md_root == P_INVALID)
continue;
count += txn->mt_dbs[i].md_branch_pages + txn->mt_dbs[i].md_leaf_pages +
txn->mt_dbs[i].md_overflow_pages;
rc = mdbx_page_search(&cx.outer, NULL, MDBX_PS_FIRST);
while (rc == MDBX_SUCCESS) {
MDBX_page *mp = cx.outer.mc_pg[cx.outer.mc_top];
for (unsigned j = 0; j < NUMKEYS(mp); j++) {
MDBX_node *leaf = NODEPTR(mp, j);
if ((leaf->mn_flags & (F_DUPDATA | F_SUBDATA)) == F_SUBDATA) {
MDBX_db db_copy, *db;
memcpy(db = &db_copy, NODEDATA(leaf), sizeof(db_copy));
if ((txn->mt_flags & MDBX_RDONLY) == 0) {
for (MDBX_dbi k = txn->mt_numdbs; --k > MAIN_DBI;) {
if ((txn->mt_dbflags[k] & MDBX_TBL_DIRTY) &&
/* txn->mt_dbxs[k].md_name.iov_len > 0 && */
NODEKSZ(leaf) == txn->mt_dbxs[k].md_name.iov_len &&
memcmp(NODEKEY(leaf), txn->mt_dbxs[k].md_name.iov_base,
NODEKSZ(leaf)) == 0) {
db = txn->mt_dbs + k;
break;
}
}
}
count +=
db->md_branch_pages + db->md_leaf_pages + db->md_overflow_pages;
}
}
rc = mdbx_cursor_sibling(&cx.outer, 1);
}
mdbx_tassert(txn, rc == MDBX_NOTFOUND);
}
if (pending + freecount + count + NUM_METAS == txn->mt_next_pgno)
return MDBX_SUCCESS;
if ((txn->mt_flags & MDBX_RDONLY) == 0)
mdbx_error("audit @%" PRIaTXN ": %u(pending) = %u(loose-count) + "
"%u(reclaimed-list) + %u(befree-pending) - %u(befree-stored)",
txn->mt_txnid, pending, txn->mt_loose_count,
txn->mt_env->me_reclaimed_pglist
? MDBX_PNL_SIZE(txn->mt_env->me_reclaimed_pglist)
: 0,
txn->mt_befree_pages ? MDBX_PNL_SIZE(txn->mt_befree_pages) : 0,
befree_stored);
mdbx_error("audit @%" PRIaTXN ": %" PRIaPGNO "(pending) + %" PRIaPGNO
"(free) + %" PRIaPGNO "(count) = %" PRIaPGNO
"(total) <> %" PRIaPGNO "(next-pgno)",
txn->mt_txnid, pending, freecount, count + NUM_METAS,
pending + freecount + count + NUM_METAS, txn->mt_next_pgno);
return MDBX_PROBLEM;
}
/* Cleanup reclaimed GC records, than save the befree-list as of this
* transaction to GC (aka freeDB). This recursive changes the reclaimed-list
* loose-list and befree-list. Keep trying until it stabilizes. */
static int mdbx_update_gc(MDBX_txn *txn) {
/* env->me_reclaimed_pglist[] can grow and shrink during this call.
* env->me_last_reclaimed and txn->mt_befree_pages[] can only grow.
* Page numbers cannot disappear from txn->mt_befree_pages[]. */
MDBX_env *const env = txn->mt_env;
const bool lifo = (env->me_flags & MDBX_LIFORECLAIM) != 0;
const char *dbg_prefix_mode = lifo ? " lifo" : " fifo";
(void)dbg_prefix_mode;
mdbx_trace("\n>>> @%" PRIaTXN, txn->mt_txnid);
unsigned befree_stored = 0, loop = 0;
MDBX_cursor mc;
int rc = mdbx_cursor_init(&mc, txn, FREE_DBI);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout_notracking;
mc.mc_next = txn->mt_cursors[FREE_DBI];
txn->mt_cursors[FREE_DBI] = &mc;
retry:
mdbx_trace(" >> restart");
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
if (unlikely(/* paranoia */ ++loop > 42)) {
mdbx_error("too more loops %u, bailout", loop);
rc = MDBX_PROBLEM;
goto bailout;
}
unsigned settled = 0, cleaned_gc_slot = 0, reused_gc_slot = 0,
filled_gc_slot = ~0u;
txnid_t cleaned_gc_id = 0, head_gc_id = env->me_last_reclaimed;
while (1) {
/* Come back here after each Put() in case befree-list changed */
MDBX_val key, data;
mdbx_trace(" >> continue");
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
if (txn->mt_lifo_reclaimed) {
if (cleaned_gc_slot < MDBX_PNL_SIZE(txn->mt_lifo_reclaimed)) {
settled = 0;
cleaned_gc_slot = 0;
reused_gc_slot = 0;
filled_gc_slot = ~0u;
/* LY: cleanup reclaimed records. */
do {
cleaned_gc_id = txn->mt_lifo_reclaimed[++cleaned_gc_slot];
mdbx_tassert(txn,
cleaned_gc_slot > 0 && cleaned_gc_id < *env->me_oldest);
key.iov_base = &cleaned_gc_id;
key.iov_len = sizeof(cleaned_gc_id);
rc = mdbx_cursor_get(&mc, &key, NULL, MDBX_SET);
if (rc == MDBX_NOTFOUND)
continue;
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
rc = mdbx_prep_backlog(txn, &mc);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
mdbx_tassert(txn, cleaned_gc_id < *env->me_oldest);
mdbx_trace("%s.cleanup-reclaimed-id [%u]%" PRIaTXN, dbg_prefix_mode,
cleaned_gc_slot, cleaned_gc_id);
mc.mc_flags |= C_RECLAIMING;
rc = mdbx_cursor_del(&mc, 0);
mc.mc_flags ^= C_RECLAIMING;
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
} while (cleaned_gc_slot < MDBX_PNL_SIZE(txn->mt_lifo_reclaimed));
mdbx_txl_sort(txn->mt_lifo_reclaimed);
head_gc_id = MDBX_PNL_LAST(txn->mt_lifo_reclaimed);
}
} else {
/* If using records from freeDB which we have not yet deleted,
* now delete them and any we reserved for me_reclaimed_pglist. */
while (cleaned_gc_id < env->me_last_reclaimed) {
rc = mdbx_cursor_first(&mc, &key, NULL);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
rc = mdbx_prep_backlog(txn, &mc);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
cleaned_gc_id = head_gc_id = *(txnid_t *)key.iov_base;
mdbx_tassert(txn, cleaned_gc_id <= env->me_last_reclaimed);
mdbx_tassert(txn, cleaned_gc_id < *env->me_oldest);
mdbx_trace("%s.cleanup-reclaimed-id %" PRIaTXN, dbg_prefix_mode,
cleaned_gc_id);
mc.mc_flags |= C_RECLAIMING;
rc = mdbx_cursor_del(&mc, 0);
mc.mc_flags ^= C_RECLAIMING;
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
settled = 0;
}
}
// handle loose pages - put ones into the reclaimed- or befree-list
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
if (mdbx_audit_enabled()) {
rc = mdbx_audit(txn, befree_stored);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
}
if (txn->mt_loose_pages) {
/* Return loose page numbers to me_reclaimed_pglist,
* though usually none are left at this point.
* The pages themselves remain in dirtylist. */
if (unlikely(!env->me_reclaimed_pglist) && !txn->mt_lifo_reclaimed &&
env->me_last_reclaimed < 1) {
/* Put loose page numbers in mt_befree_pages,
* since unable to return them to me_reclaimed_pglist. */
if (unlikely((rc = mdbx_pnl_need(&txn->mt_befree_pages,
txn->mt_loose_count)) != 0))
goto bailout;
for (MDBX_page *mp = txn->mt_loose_pages; mp; mp = NEXT_LOOSE_PAGE(mp))
mdbx_pnl_xappend(txn->mt_befree_pages, mp->mp_pgno);
mdbx_trace("%s: append %u loose-pages to befree-pages", dbg_prefix_mode,
txn->mt_loose_count);
} else {
/* Room for loose pages + temp PNL with same */
if (likely(env->me_reclaimed_pglist != NULL)) {
rc = mdbx_pnl_need(&env->me_reclaimed_pglist,
2 * txn->mt_loose_count + 2);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
MDBX_PNL loose = env->me_reclaimed_pglist +
MDBX_PNL_ALLOCLEN(env->me_reclaimed_pglist) -
txn->mt_loose_count - 1;
unsigned count = 0;
for (MDBX_page *mp = txn->mt_loose_pages; mp;
mp = NEXT_LOOSE_PAGE(mp))
loose[++count] = mp->mp_pgno;
MDBX_PNL_SIZE(loose) = count;
mdbx_pnl_sort(loose);
mdbx_pnl_xmerge(env->me_reclaimed_pglist, loose);
} else {
env->me_reclaimed_pglist = mdbx_pnl_alloc(txn->mt_loose_count);
if (unlikely(env->me_reclaimed_pglist == NULL)) {
rc = MDBX_ENOMEM;
goto bailout;
}
for (MDBX_page *mp = txn->mt_loose_pages; mp;
mp = NEXT_LOOSE_PAGE(mp))
mdbx_pnl_xappend(env->me_reclaimed_pglist, mp->mp_pgno);
mdbx_pnl_sort(env->me_reclaimed_pglist);
}
mdbx_trace("%s: append %u loose-pages to reclaimed-pages",
dbg_prefix_mode, txn->mt_loose_count);
}
// filter-out list of dirty-pages from loose-pages
MDBX_DPL dl = txn->mt_rw_dirtylist;
mdbx_dpl_sort(dl);
unsigned left = dl->length;
for (MDBX_page *mp = txn->mt_loose_pages; mp;) {
mdbx_tassert(txn, mp->mp_pgno < txn->mt_next_pgno);
mdbx_ensure(env, mp->mp_pgno >= NUM_METAS);
if (left > 0) {
const unsigned i = mdbx_dpl_search(dl, mp->mp_pgno);
if (i <= dl->length && dl[i].pgno == mp->mp_pgno) {
mdbx_tassert(txn, i > 0 && dl[i].ptr != dl);
dl[i].ptr = dl /* mark for deletion */;
}
left -= 1;
}
MDBX_page *dp = mp;
mp = NEXT_LOOSE_PAGE(mp);
if ((env->me_flags & MDBX_WRITEMAP) == 0)
mdbx_dpage_free(env, dp, 1);
}
if (left > 0) {
MDBX_DPL r, w, end = dl + dl->length;
for (r = w = dl + 1; r <= end; r++) {
if (r->ptr != dl) {
if (r != w)
*w = *r;
++w;
}
}
mdbx_tassert(txn, w - dl == (int)left + 1);
}
if (left != dl->length)
mdbx_trace("%s: filtered-out loose-pages from %u -> %u dirty-pages",
dbg_prefix_mode, dl->length, left);
dl->length = left;
txn->mt_loose_pages = NULL;
txn->mt_loose_count = 0;
if (mdbx_audit_enabled()) {
rc = mdbx_audit(txn, befree_stored);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
}
}
// handle reclaimed pages - return suitable into unallocated space
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
if (env->me_reclaimed_pglist) {
pgno_t tail = txn->mt_next_pgno;
pgno_t *const begin = MDBX_PNL_BEGIN(env->me_reclaimed_pglist);
pgno_t *const end = MDBX_PNL_END(env->me_reclaimed_pglist);
pgno_t *higest;
#if MDBX_PNL_ASCENDING
for (higest = end; --higest >= begin;) {
#else
for (higest = begin; higest < end; ++higest) {
#endif /* MDBX_PNL sort-order */
mdbx_tassert(txn, *higest >= NUM_METAS && *higest < tail);
if (*higest != tail - 1)
break;
tail -= 1;
}
if (tail != txn->mt_next_pgno) {
#if MDBX_PNL_ASCENDING
MDBX_PNL_SIZE(env->me_reclaimed_pglist) =
(unsigned)(higest + 1 - begin);
#else
MDBX_PNL_SIZE(env->me_reclaimed_pglist) -= (unsigned)(higest - begin);
for (pgno_t *move = begin; higest < end; ++move, ++higest)
*move = *higest;
#endif /* MDBX_PNL sort-order */
mdbx_info(
"%s.refunded %" PRIaPGNO " pages: %" PRIaPGNO " -> %" PRIaPGNO,
dbg_prefix_mode, txn->mt_next_pgno - tail, tail, txn->mt_next_pgno);
txn->mt_next_pgno = tail;
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
if (mdbx_audit_enabled()) {
rc = mdbx_audit(txn, befree_stored);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
}
}
}
// handle befree-list - store ones into singe gc-record
if (befree_stored < MDBX_PNL_SIZE(txn->mt_befree_pages)) {
if (unlikely(!befree_stored)) {
/* Make sure last page of freeDB is touched and on befree-list */
rc = mdbx_page_search(&mc, NULL, MDBX_PS_LAST | MDBX_PS_MODIFY);
if (unlikely(rc != MDBX_SUCCESS && rc != MDBX_NOTFOUND))
goto bailout;
}
/* Write to last page of freeDB */
key.iov_len = sizeof(txn->mt_txnid);
key.iov_base = &txn->mt_txnid;
do {
data.iov_len = MDBX_PNL_SIZEOF(txn->mt_befree_pages);
rc = mdbx_cursor_put(&mc, &key, &data, MDBX_RESERVE);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
/* Retry if mt_befree_pages[] grew during the Put() */
} while (data.iov_len < MDBX_PNL_SIZEOF(txn->mt_befree_pages));
befree_stored = (unsigned)MDBX_PNL_SIZE(txn->mt_befree_pages);
mdbx_pnl_sort(txn->mt_befree_pages);
memcpy(data.iov_base, txn->mt_befree_pages, data.iov_len);
mdbx_trace("%s.put-befree #%u @ %" PRIaTXN, dbg_prefix_mode,
befree_stored, txn->mt_txnid);
if (mdbx_debug_enabled(MDBX_DBG_EXTRA)) {
unsigned i = befree_stored;
mdbx_debug_extra("PNL write txn %" PRIaTXN " root %" PRIaPGNO
" num %u, PNL",
txn->mt_txnid, txn->mt_dbs[FREE_DBI].md_root, i);
for (; i; i--)
mdbx_debug_extra_print(" %" PRIaPGNO, txn->mt_befree_pages[i]);
mdbx_debug_extra_print("\n");
}
continue;
}
// handle reclaimed and loost pages - merge and store both into gc
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
mdbx_tassert(txn, txn->mt_loose_count == 0);
mdbx_trace(" >> reserving");
if (mdbx_audit_enabled()) {
rc = mdbx_audit(txn, befree_stored);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
}
const unsigned amount =
env->me_reclaimed_pglist ? MDBX_PNL_SIZE(env->me_reclaimed_pglist) : 0;
const unsigned left = amount - settled;
mdbx_trace("%s: amount %u, settled %d, left %d, lifo-reclaimed-slots %u, "
"reused-gc-slots %u",
dbg_prefix_mode, amount, settled, (int)left,
txn->mt_lifo_reclaimed
? (unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed)
: 0,
reused_gc_slot);
if (0 >= (int)left)
break;
if (unlikely(head_gc_id == 0)) {
head_gc_id = mdbx_find_oldest(txn) - 1;
if (txn->mt_lifo_reclaimed == NULL) {
rc = mdbx_cursor_get(&mc, &key, NULL, MDBX_FIRST);
if (unlikely(rc != MDBX_SUCCESS)) {
if (rc != MDBX_NOTFOUND)
goto bailout;
} else if (unlikely(key.iov_len != sizeof(txnid_t))) {
rc = MDBX_CORRUPTED;
goto bailout;
} else {
txnid_t first_txn;
memcpy(&first_txn, key.iov_base, sizeof(txnid_t));
if (head_gc_id >= first_txn)
head_gc_id = first_txn - 1;
}
}
}
const unsigned prefer_max_scatter = 257;
txnid_t reservation_gc_id;
if (lifo) {
mdbx_tassert(txn, txn->mt_lifo_reclaimed != NULL);
if (unlikely(!txn->mt_lifo_reclaimed)) {
txn->mt_lifo_reclaimed = mdbx_txl_alloc();
if (unlikely(!txn->mt_lifo_reclaimed)) {
rc = MDBX_ENOMEM;
goto bailout;
}
}
if (head_gc_id > 1 &&
MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) < prefer_max_scatter &&
left > ((unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) -
reused_gc_slot) *
env->me_maxgc_ov1page) {
/* LY: need just a txn-id for save page list. */
rc = mdbx_page_alloc(&mc, 0, NULL, MDBX_ALLOC_GC | MDBX_ALLOC_KICK);
if (likely(rc == MDBX_SUCCESS)) {
/* LY: ok, reclaimed from freedb. */
mdbx_trace("%s: took @%" PRIaTXN " from GC, continue",
dbg_prefix_mode, MDBX_PNL_LAST(txn->mt_lifo_reclaimed));
continue;
}
if (unlikely(rc != MDBX_NOTFOUND))
/* LY: other troubles... */
goto bailout;
/* LY: freedb is empty, will look any free txn-id in high2low order. */
do {
--head_gc_id;
mdbx_assert(env,
MDBX_PNL_IS_EMPTY(txn->mt_lifo_reclaimed) ||
MDBX_PNL_LAST(txn->mt_lifo_reclaimed) > head_gc_id);
rc = mdbx_txl_append(&txn->mt_lifo_reclaimed, head_gc_id);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
cleaned_gc_slot += 1 /* mark GC cleanup is not needed. */;
mdbx_trace("%s: append @%" PRIaTXN
" to lifo-reclaimed, cleaned-gc-slot = %u",
dbg_prefix_mode, head_gc_id, cleaned_gc_slot);
} while (head_gc_id > 1 &&
MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) < prefer_max_scatter &&
left > ((unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) -
reused_gc_slot) *
env->me_maxgc_ov1page);
}
if ((unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) <= reused_gc_slot) {
mdbx_notice("** restart: reserve depleted (reused_gc_slot %u >= "
"lifo_reclaimed %u" PRIaTXN,
reused_gc_slot,
(unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed));
goto retry;
}
const unsigned i =
(unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) - reused_gc_slot;
mdbx_tassert(txn, i > 0 && i <= MDBX_PNL_SIZE(txn->mt_lifo_reclaimed));
reservation_gc_id = txn->mt_lifo_reclaimed[i];
mdbx_trace("%s: take @%" PRIaTXN " from lifo-reclaimed[%u]",
dbg_prefix_mode, reservation_gc_id, i);
} else {
mdbx_tassert(txn, txn->mt_lifo_reclaimed == NULL);
reservation_gc_id = head_gc_id--;
mdbx_trace("%s: take @%" PRIaTXN " from head-gc-id", dbg_prefix_mode,
reservation_gc_id);
}
++reused_gc_slot;
unsigned chunk = left;
if (unlikely(chunk > env->me_maxgc_ov1page)) {
const unsigned avail_gs_slots =
txn->mt_lifo_reclaimed
? (unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) -
reused_gc_slot + 1
: (head_gc_id < INT16_MAX) ? (unsigned)head_gc_id : INT16_MAX;
if (avail_gs_slots > 1) {
if (chunk < env->me_maxgc_ov1page * 2)
chunk /= 2;
else {
const unsigned threshold =
env->me_maxgc_ov1page * ((avail_gs_slots < prefer_max_scatter)
? avail_gs_slots
: prefer_max_scatter);
if (left < threshold)
chunk = env->me_maxgc_ov1page;
else {
const unsigned tail = left - threshold + env->me_maxgc_ov1page + 1;
unsigned span = 1;
unsigned avail = (unsigned)((pgno2bytes(env, span) - PAGEHDRSZ) /
sizeof(pgno_t)) /*- 1 + span */;
if (tail > avail) {
for (unsigned i = amount - span; i > 0; --i) {
if (MDBX_PNL_ASCENDING
? (env->me_reclaimed_pglist[i] + span)
: (env->me_reclaimed_pglist[i] - span) ==
env->me_reclaimed_pglist[i + span]) {
span += 1;
avail = (unsigned)((pgno2bytes(env, span) - PAGEHDRSZ) /
sizeof(pgno_t)) -
1 + span;
if (avail >= tail)
break;
}
}
}
chunk = (avail >= tail) ? tail - span
: (avail_gs_slots > 3 &&
reused_gc_slot < prefer_max_scatter - 3)
? avail - span
: tail;
}
}
}
}
mdbx_tassert(txn, chunk > 0);
mdbx_trace("%s: head_gc_id %" PRIaTXN ", reused_gc_slot %u, reservation-id "
"%" PRIaTXN,
dbg_prefix_mode, head_gc_id, reused_gc_slot, reservation_gc_id);
mdbx_trace("%s: chunk %u, gc-per-ovpage %u", dbg_prefix_mode, chunk,
env->me_maxgc_ov1page);
mdbx_tassert(txn, reservation_gc_id < *env->me_oldest);
if (unlikely(reservation_gc_id < 1 ||
reservation_gc_id >= *env->me_oldest)) {
/* LY: not any txn in the past of freedb. */
rc = MDBX_PROBLEM;
goto bailout;
}
key.iov_len = sizeof(reservation_gc_id);
key.iov_base = &reservation_gc_id;
data.iov_len = (chunk + 1) * sizeof(pgno_t);
mdbx_trace("%s.reserve: %u [%u...%u] @%" PRIaTXN, dbg_prefix_mode, chunk,
settled + 1, settled + chunk + 1, reservation_gc_id);
rc = mdbx_cursor_put(&mc, &key, &data, MDBX_RESERVE | MDBX_NOOVERWRITE);
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
/* PNL is initially empty, zero out at least the length */
memset(data.iov_base, 0, sizeof(pgno_t));
settled += chunk;
mdbx_trace("%s.settled %u (+%u), continue", dbg_prefix_mode, settled,
chunk);
if (txn->mt_lifo_reclaimed &&
unlikely(amount < MDBX_PNL_SIZE(env->me_reclaimed_pglist))) {
mdbx_notice("** restart: reclaimed-list growth %u -> %u", amount,
(unsigned)MDBX_PNL_SIZE(env->me_reclaimed_pglist));
goto retry;
}
continue;
}
mdbx_tassert(
txn,
cleaned_gc_slot ==
(txn->mt_lifo_reclaimed ? MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) : 0));
mdbx_trace(" >> filling");
/* Fill in the reserved records */
filled_gc_slot =
txn->mt_lifo_reclaimed
? (unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) - reused_gc_slot
: reused_gc_slot;
rc = MDBX_SUCCESS;
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
if (env->me_reclaimed_pglist && MDBX_PNL_SIZE(env->me_reclaimed_pglist)) {
MDBX_val key, data;
key.iov_len = data.iov_len = 0; /* avoid MSVC warning */
key.iov_base = data.iov_base = NULL;
const unsigned amount = MDBX_PNL_SIZE(env->me_reclaimed_pglist);
unsigned left = amount;
if (txn->mt_lifo_reclaimed == nullptr) {
mdbx_tassert(txn, lifo == 0);
rc = mdbx_cursor_first(&mc, &key, &data);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
} else {
mdbx_tassert(txn, lifo != 0);
}
while (1) {
txnid_t fill_gc_id;
mdbx_trace("%s: left %u of %u", dbg_prefix_mode, left,
(unsigned)MDBX_PNL_SIZE(env->me_reclaimed_pglist));
if (txn->mt_lifo_reclaimed == nullptr) {
mdbx_tassert(txn, lifo == 0);
fill_gc_id = *(txnid_t *)key.iov_base;
if (filled_gc_slot-- == 0 || fill_gc_id > env->me_last_reclaimed) {
mdbx_notice(
"** restart: reserve depleted (filled_slot %u, fill_id %" PRIaTXN
" > last_reclaimed %" PRIaTXN,
filled_gc_slot, fill_gc_id, env->me_last_reclaimed);
goto retry;
}
} else {
mdbx_tassert(txn, lifo != 0);
if (++filled_gc_slot >
(unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed)) {
mdbx_notice("** restart: reserve depleted (filled_gc_slot %u > "
"lifo_reclaimed %u" PRIaTXN,
filled_gc_slot,
(unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed));
goto retry;
}
fill_gc_id = txn->mt_lifo_reclaimed[filled_gc_slot];
mdbx_trace("%s.seek-reservation @%" PRIaTXN " at lifo_reclaimed[%u]",
dbg_prefix_mode, fill_gc_id, filled_gc_slot);
key.iov_base = &fill_gc_id;
key.iov_len = sizeof(fill_gc_id);
rc = mdbx_cursor_get(&mc, &key, &data, MDBX_SET_KEY);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
}
mdbx_tassert(txn, cleaned_gc_slot ==
(txn->mt_lifo_reclaimed
? MDBX_PNL_SIZE(txn->mt_lifo_reclaimed)
: 0));
mdbx_tassert(txn, fill_gc_id > 0 && fill_gc_id < *env->me_oldest);
key.iov_base = &fill_gc_id;
key.iov_len = sizeof(fill_gc_id);
mdbx_tassert(txn, data.iov_len >= sizeof(pgno_t) * 2);
mc.mc_flags |= C_RECLAIMING | C_GCFREEZE;
unsigned chunk = (unsigned)(data.iov_len / sizeof(pgno_t)) - 1;
if (unlikely(chunk > left)) {
mdbx_trace("%s: chunk %u > left %u, @%" PRIaTXN, dbg_prefix_mode, chunk,
left, fill_gc_id);
if (loop < 5 || chunk - left > env->me_maxgc_ov1page) {
data.iov_len = (left + 1) * sizeof(pgno_t);
if (loop < 21)
mc.mc_flags -= C_GCFREEZE;
}
chunk = left;
}
rc = mdbx_cursor_put(&mc, &key, &data, MDBX_CURRENT | MDBX_RESERVE);
mc.mc_flags &= ~(C_RECLAIMING | C_GCFREEZE);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
if (unlikely(txn->mt_loose_count ||
amount != MDBX_PNL_SIZE(env->me_reclaimed_pglist))) {
memset(data.iov_base, 0, sizeof(pgno_t));
mdbx_notice("** restart: reclaimed-list changed (%u -> %u, %u)", amount,
MDBX_PNL_SIZE(env->me_reclaimed_pglist),
txn->mt_loose_count);
goto retry;
}
if (unlikely(txn->mt_lifo_reclaimed
? cleaned_gc_slot < MDBX_PNL_SIZE(txn->mt_lifo_reclaimed)
: cleaned_gc_id < env->me_last_reclaimed)) {
memset(data.iov_base, 0, sizeof(pgno_t));
mdbx_notice("** restart: reclaimed-slots changed");
goto retry;
}
pgno_t *dst = data.iov_base;
*dst++ = chunk;
pgno_t *src = MDBX_PNL_BEGIN(env->me_reclaimed_pglist) + left - chunk;
memcpy(dst, src, chunk * sizeof(pgno_t));
pgno_t *from = src, *to = src + chunk;
mdbx_trace("%s.fill: %u [ %u:%" PRIaPGNO "...%u:%" PRIaPGNO
"] @%" PRIaTXN,
dbg_prefix_mode, chunk,
(unsigned)(from - env->me_reclaimed_pglist), from[0],
(unsigned)(to - env->me_reclaimed_pglist), to[-1], fill_gc_id);
left -= chunk;
if (mdbx_audit_enabled()) {
rc = mdbx_audit(txn, befree_stored + amount - left);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
}
if (left == 0) {
rc = MDBX_SUCCESS;
break;
}
if (txn->mt_lifo_reclaimed == nullptr) {
mdbx_tassert(txn, lifo == 0);
rc = mdbx_cursor_next(&mc, &key, &data, MDBX_NEXT);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
} else {
mdbx_tassert(txn, lifo != 0);
}
}
}
mdbx_tassert(txn, rc == MDBX_SUCCESS);
if (unlikely(txn->mt_loose_count != 0 ||
filled_gc_slot !=
(txn->mt_lifo_reclaimed
? (unsigned)MDBX_PNL_SIZE(txn->mt_lifo_reclaimed)
: 0))) {
mdbx_notice("** restart: reserve excess (filled-slot %u, loose-count %u)",
filled_gc_slot, txn->mt_loose_count);
goto retry;
}
mdbx_tassert(txn,
txn->mt_lifo_reclaimed == NULL ||
cleaned_gc_slot == MDBX_PNL_SIZE(txn->mt_lifo_reclaimed));
bailout:
txn->mt_cursors[FREE_DBI] = mc.mc_next;
bailout_notracking:
if (txn->mt_lifo_reclaimed) {
MDBX_PNL_SIZE(txn->mt_lifo_reclaimed) = 0;
if (txn != env->me_txn0) {
mdbx_txl_free(txn->mt_lifo_reclaimed);
txn->mt_lifo_reclaimed = NULL;
}
}
mdbx_trace("<<< %u loops, rc = %d", loop, rc);
return rc;
}
/* Flush (some) dirty pages to the map, after clearing their dirty flag.
* [in] txn the transaction that's being committed
* [in] keep number of initial pages in dirtylist to keep dirty.
* Returns 0 on success, non-zero on failure. */
static int mdbx_page_flush(MDBX_txn *txn, pgno_t keep) {
MDBX_env *env = txn->mt_env;
MDBX_DPL dl = txn->mt_rw_dirtylist;
unsigned i, j, pagecount = dl->length;
int rc;
size_t size = 0, pos = 0;
pgno_t pgno = 0;
MDBX_page *dp = NULL;
struct iovec iov[MDBX_COMMIT_PAGES];
intptr_t wpos = 0, wsize = 0;
size_t next_pos = 1; /* impossible pos, so pos != next_pos */
int n = 0;
j = i = keep;
if (env->me_flags & MDBX_WRITEMAP) {
/* Clear dirty flags */
while (++i <= pagecount) {
dp = dl[i].ptr;
/* Don't flush this page yet */
if (dp->mp_flags & (P_LOOSE | P_KEEP)) {
dp->mp_flags &= ~P_KEEP;
dl[++j] = dl[i];
continue;
}
dp->mp_flags &= ~P_DIRTY;
dp->mp_validator = 0 /* TODO */;
env->me_sync_pending +=
IS_OVERFLOW(dp) ? pgno2bytes(env, dp->mp_pages) : env->me_psize;
}
goto done;
}
/* Write the pages */
for (;;) {
if (++i <= pagecount) {
dp = dl[i].ptr;
/* Don't flush this page yet */
if (dp->mp_flags & (P_LOOSE | P_KEEP)) {
dp->mp_flags &= ~P_KEEP;
dl[i].pgno = 0;
continue;
}
pgno = dl[i].pgno;
mdbx_tassert(txn, pgno >= MIN_PAGENO);
/* clear dirty flag */
dp->mp_flags &= ~P_DIRTY;
dp->mp_validator = 0 /* TODO */;
pos = pgno2bytes(env, pgno);
size = IS_OVERFLOW(dp) ? pgno2bytes(env, dp->mp_pages) : env->me_psize;
env->me_sync_pending += size;
}
/* Write up to MDBX_COMMIT_PAGES dirty pages at a time. */
if (pos != next_pos || n == MDBX_COMMIT_PAGES || wsize + size > MAX_WRITE) {
if (n) {
/* Write previous page(s) */
rc = mdbx_pwritev(env->me_fd, iov, n, wpos, wsize);
if (unlikely(rc != MDBX_SUCCESS)) {
mdbx_debug("Write error: %s", mdbx_strerror(rc));
return rc;
}
n = 0;
}
if (i > pagecount)
break;
wpos = pos;
wsize = 0;
}
mdbx_debug("committing page %" PRIaPGNO, pgno);
next_pos = pos + size;
iov[n].iov_len = size;
iov[n].iov_base = (char *)dp;
wsize += size;
n++;
}
mdbx_invalidate_cache(env->me_map, pgno2bytes(env, txn->mt_next_pgno));
for (i = keep; ++i <= pagecount;) {
dp = dl[i].ptr;
/* This is a page we skipped above */
if (!dl[i].pgno) {
dl[++j] = dl[i];
dl[j].pgno = dp->mp_pgno;
continue;
}
mdbx_dpage_free(env, dp, IS_OVERFLOW(dp) ? dp->mp_pages : 1);
}
done:
i--;
txn->mt_dirtyroom += i - j;
dl->length = j;
return MDBX_SUCCESS;
}
/* Check for misused dbi handles */
#define TXN_DBI_CHANGED(txn, dbi) \
((txn)->mt_dbiseqs[dbi] != (txn)->mt_env->me_dbiseqs[dbi])
/* Import DBI which opened after txn started into context */
static __cold bool mdbx_txn_import_dbi(MDBX_txn *txn, MDBX_dbi dbi) {
MDBX_env *env = txn->mt_env;
if (dbi < CORE_DBS || dbi >= env->me_numdbs)
return false;
mdbx_ensure(env, mdbx_fastmutex_acquire(&env->me_dbi_lock) == MDBX_SUCCESS);
const unsigned snap_numdbs = env->me_numdbs;
mdbx_compiler_barrier();
for (unsigned i = CORE_DBS; i < snap_numdbs; ++i) {
if (i >= txn->mt_numdbs)
txn->mt_dbflags[i] = 0;
if (!(txn->mt_dbflags[i] & DB_USRVALID) &&
(env->me_dbflags[i] & MDBX_VALID)) {
txn->mt_dbs[i].md_flags = env->me_dbflags[i] & PERSISTENT_FLAGS;
txn->mt_dbflags[i] = DB_VALID | DB_USRVALID | DB_STALE;
mdbx_tassert(txn, txn->mt_dbxs[i].md_cmp != NULL);
}
}
txn->mt_numdbs = snap_numdbs;
mdbx_ensure(env, mdbx_fastmutex_release(&env->me_dbi_lock) == MDBX_SUCCESS);
return txn->mt_dbflags[dbi] & DB_USRVALID;
}
/* Check txn and dbi arguments to a function */
static __inline bool TXN_DBI_EXIST(MDBX_txn *txn, MDBX_dbi dbi,
unsigned validity) {
if (likely(dbi < txn->mt_numdbs && (txn->mt_dbflags[dbi] & validity)))
return true;
return mdbx_txn_import_dbi(txn, dbi);
}
int mdbx_txn_commit(MDBX_txn *txn) {
int rc;
if (unlikely(txn == NULL))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
MDBX_env *env = txn->mt_env;
if (unlikely(env->me_pid != mdbx_getpid())) {
env->me_flags |= MDBX_FATAL_ERROR;
return MDBX_PANIC;
}
if (txn->mt_child) {
rc = mdbx_txn_commit(txn->mt_child);
txn->mt_child = NULL;
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
}
/* mdbx_txn_end() mode for a commit which writes nothing */
unsigned end_mode =
MDBX_END_EMPTY_COMMIT | MDBX_END_UPDATE | MDBX_END_SLOT | MDBX_END_FREE;
if (unlikely(F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY)))
goto done;
if (unlikely(txn->mt_flags & (MDBX_TXN_FINISHED | MDBX_TXN_ERROR))) {
mdbx_debug("error flag is set, can't commit");
if (txn->mt_parent)
txn->mt_parent->mt_flags |= MDBX_TXN_ERROR;
rc = MDBX_BAD_TXN;
goto fail;
}
if (txn->mt_parent) {
MDBX_txn *parent = txn->mt_parent;
MDBX_page **lp;
MDBX_DPL dst, src;
MDBX_PNL pspill;
unsigned i, x, y, len, ps_len;
/* Append our reclaim list to parent's */
if (txn->mt_lifo_reclaimed) {
if (parent->mt_lifo_reclaimed) {
rc = mdbx_txl_append_list(&parent->mt_lifo_reclaimed,
txn->mt_lifo_reclaimed);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
mdbx_txl_free(txn->mt_lifo_reclaimed);
} else
parent->mt_lifo_reclaimed = txn->mt_lifo_reclaimed;
txn->mt_lifo_reclaimed = NULL;
}
/* Append our free list to parent's */
rc = mdbx_pnl_append_list(&parent->mt_befree_pages, txn->mt_befree_pages);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
mdbx_pnl_free(txn->mt_befree_pages);
/* Failures after this must either undo the changes
* to the parent or set MDBX_TXN_ERROR in the parent. */
parent->mt_next_pgno = txn->mt_next_pgno;
parent->mt_end_pgno = txn->mt_end_pgno;
parent->mt_flags = txn->mt_flags;
/* Merge our cursors into parent's and close them */
mdbx_cursors_eot(txn, 1);
/* Update parent's DB table. */
memcpy(parent->mt_dbs, txn->mt_dbs, txn->mt_numdbs * sizeof(MDBX_db));
parent->mt_numdbs = txn->mt_numdbs;
parent->mt_dbflags[FREE_DBI] = txn->mt_dbflags[FREE_DBI];
parent->mt_dbflags[MAIN_DBI] = txn->mt_dbflags[MAIN_DBI];
for (i = CORE_DBS; i < txn->mt_numdbs; i++) {
/* preserve parent's DB_NEW status */
parent->mt_dbflags[i] =
txn->mt_dbflags[i] | (parent->mt_dbflags[i] & (DB_CREAT | DB_FRESH));
}
dst = parent->mt_rw_dirtylist;
src = txn->mt_rw_dirtylist;
/* Remove anything in our dirty list from parent's spill list */
if ((pspill = parent->mt_spill_pages) && (ps_len = MDBX_PNL_SIZE(pspill))) {
x = y = ps_len;
MDBX_PNL_SIZE(pspill) = ~(pgno_t)0;
/* Mark our dirty pages as deleted in parent spill list */
for (i = 0, len = src->length; ++i <= len;) {
pgno_t pn = src[i].pgno << 1;
while (pn > pspill[x])
x--;
if (pn == pspill[x]) {
pspill[x] = 1;
y = --x;
}
}
/* Squash deleted pagenums if we deleted any */
for (x = y; ++x <= ps_len;)
if ((pspill[x] & 1) == 0)
pspill[++y] = pspill[x];
MDBX_PNL_SIZE(pspill) = y;
}
/* Remove anything in our spill list from parent's dirty list */
if (txn->mt_spill_pages && MDBX_PNL_SIZE(txn->mt_spill_pages)) {
for (i = 1; i <= MDBX_PNL_SIZE(txn->mt_spill_pages); i++) {
pgno_t pn = txn->mt_spill_pages[i];
if (pn & 1)
continue; /* deleted spillpg */
pn >>= 1;
y = mdbx_dpl_search(dst, pn);
if (y <= dst->length && dst[y].pgno == pn) {
mdbx_free(dst[y].ptr);
while (y < dst->length) {
dst[y] = dst[y + 1];
y++;
}
dst->length--;
}
}
}
/* Find len = length of merging our dirty list with parent's */
x = dst->length;
dst->length = 0; /* simplify loops */
if (parent->mt_parent) {
len = x + src->length;
y = mdbx_dpl_search(src, dst[x].pgno + 1) - 1;
for (i = x; y && i; y--) {
pgno_t yp = src[y].pgno;
while (yp < dst[i].pgno)
i--;
if (yp == dst[i].pgno) {
i--;
len--;
}
}
} else { /* Simplify the above for single-ancestor case */
len = MDBX_DPL_TXNFULL - txn->mt_dirtyroom;
}
/* Merge our dirty list with parent's */
y = src->length;
for (i = len; y; dst[i--] = src[y--]) {
pgno_t yp = src[y].pgno;
while (yp < dst[x].pgno)
dst[i--] = dst[x--];
if (yp == dst[x].pgno)
mdbx_free(dst[x--].ptr);
}
mdbx_tassert(txn, i == x);
dst->length = len;
mdbx_free(txn->mt_rw_dirtylist);
parent->mt_dirtyroom = txn->mt_dirtyroom;
if (txn->mt_spill_pages) {
if (parent->mt_spill_pages) {
/* TODO: Prevent failure here, so parent does not fail */
rc = mdbx_pnl_append_list(&parent->mt_spill_pages, txn->mt_spill_pages);
if (unlikely(rc != MDBX_SUCCESS))
parent->mt_flags |= MDBX_TXN_ERROR;
mdbx_pnl_free(txn->mt_spill_pages);
mdbx_pnl_sort(parent->mt_spill_pages);
} else {
parent->mt_spill_pages = txn->mt_spill_pages;
}
}
/* Append our loose page list to parent's */
for (lp = &parent->mt_loose_pages; *lp; lp = &NEXT_LOOSE_PAGE(*lp))
;
*lp = txn->mt_loose_pages;
parent->mt_loose_count += txn->mt_loose_count;
parent->mt_child = NULL;
mdbx_pnl_free(((MDBX_ntxn *)txn)->mnt_pgstate.mf_reclaimed_pglist);
txn->mt_signature = 0;
mdbx_free(txn);
return rc;
}
if (unlikely(txn != env->me_txn)) {
mdbx_debug("attempt to commit unknown transaction");
rc = MDBX_EINVAL;
goto fail;
}
mdbx_cursors_eot(txn, 0);
end_mode |= MDBX_END_EOTDONE;
if (txn->mt_rw_dirtylist->length == 0 &&
!(txn->mt_flags & (MDBX_TXN_DIRTY | MDBX_TXN_SPILLS)))
goto done;
mdbx_debug("committing txn %" PRIaTXN " %p on mdbenv %p, root page %" PRIaPGNO
"/%" PRIaPGNO,
txn->mt_txnid, (void *)txn, (void *)env,
txn->mt_dbs[MAIN_DBI].md_root, txn->mt_dbs[FREE_DBI].md_root);
/* Update DB root pointers */
if (txn->mt_numdbs > CORE_DBS) {
MDBX_cursor mc;
MDBX_dbi i;
MDBX_val data;
data.iov_len = sizeof(MDBX_db);
rc = mdbx_cursor_init(&mc, txn, MAIN_DBI);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
for (i = CORE_DBS; i < txn->mt_numdbs; i++) {
if (txn->mt_dbflags[i] & DB_DIRTY) {
if (unlikely(TXN_DBI_CHANGED(txn, i))) {
rc = MDBX_BAD_DBI;
goto fail;
}
data.iov_base = &txn->mt_dbs[i];
WITH_CURSOR_TRACKING(mc,
rc = mdbx_cursor_put(&mc, &txn->mt_dbxs[i].md_name,
&data, F_SUBDATA));
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
}
}
}
rc = mdbx_update_gc(txn);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
mdbx_pnl_free(env->me_reclaimed_pglist);
env->me_reclaimed_pglist = NULL;
mdbx_pnl_shrink(&txn->mt_befree_pages);
if (mdbx_audit_enabled()) {
rc = mdbx_audit(txn, 0);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
}
rc = mdbx_page_flush(txn, 0);
if (likely(rc == MDBX_SUCCESS)) {
MDBX_meta meta, *head = mdbx_meta_head(env);
meta.mm_magic_and_version = head->mm_magic_and_version;
meta.mm_extra_flags = head->mm_extra_flags;
meta.mm_validator_id = head->mm_validator_id;
meta.mm_extra_pagehdr = head->mm_extra_pagehdr;
meta.mm_geo = head->mm_geo;
meta.mm_geo.next = txn->mt_next_pgno;
meta.mm_geo.now = txn->mt_end_pgno;
meta.mm_dbs[FREE_DBI] = txn->mt_dbs[FREE_DBI];
meta.mm_dbs[MAIN_DBI] = txn->mt_dbs[MAIN_DBI];
meta.mm_canary = txn->mt_canary;
mdbx_meta_set_txnid(env, &meta, txn->mt_txnid);
rc = mdbx_sync_locked(
env, env->me_flags | txn->mt_flags | MDBX_SHRINK_ALLOWED, &meta);
}
if (unlikely(rc != MDBX_SUCCESS)) {
env->me_flags |= MDBX_FATAL_ERROR;
goto fail;
}
if (likely(env->me_lck))
env->me_lck->mti_readers_refresh_flag = false;
end_mode = MDBX_END_COMMITTED | MDBX_END_UPDATE | MDBX_END_EOTDONE;
done:
return mdbx_txn_end(txn, end_mode);
fail:
mdbx_txn_abort(txn);
return rc;
}
/* Read the environment parameters of a DB environment
* before mapping it into memory. */
static int __cold mdbx_read_header(MDBX_env *env, MDBX_meta *meta,
uint64_t *filesize) {
STATIC_ASSERT(offsetof(MDBX_page, mp_meta) == PAGEHDRSZ);
int rc = mdbx_filesize(env->me_fd, filesize);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
memset(meta, 0, sizeof(MDBX_meta));
meta->mm_datasync_sign = MDBX_DATASIGN_WEAK;
rc = MDBX_CORRUPTED;
/* Read twice all meta pages so we can find the latest one. */
unsigned loop_limit = NUM_METAS * 2;
for (unsigned loop_count = 0; loop_count < loop_limit; ++loop_count) {
MDBX_page page;
/* We don't know the page size on first time.
* So, just guess it. */
unsigned guess_pagesize = meta->mm_psize;
if (guess_pagesize == 0)
guess_pagesize =
(loop_count > NUM_METAS) ? env->me_psize : env->me_os_psize;
const unsigned meta_number = loop_count % NUM_METAS;
const unsigned offset = guess_pagesize * meta_number;
unsigned retryleft = 42;
while (1) {
mdbx_trace("reading meta[%d]: offset %u, bytes %u, retry-left %u",
meta_number, offset, (unsigned)sizeof(page), retryleft);
int err = mdbx_pread(env->me_fd, &page, sizeof(page), offset);
if (err != MDBX_SUCCESS) {
mdbx_error("read meta[%u,%u]: %i, %s", offset, (unsigned)sizeof(page),
err, mdbx_strerror(err));
return err;
}
MDBX_page again;
err = mdbx_pread(env->me_fd, &again, sizeof(again), offset);
if (err != MDBX_SUCCESS) {
mdbx_error("read meta[%u,%u]: %i, %s", offset, (unsigned)sizeof(again),
err, mdbx_strerror(err));
return err;
}
if (memcmp(&page, &again, sizeof(page)) == 0 || --retryleft == 0)
break;
mdbx_info("meta[%u] was updated, re-read it", meta_number);
}
if (page.mp_meta.mm_magic_and_version != MDBX_DATA_MAGIC &&
page.mp_meta.mm_magic_and_version != MDBX_DATA_MAGIC_DEVEL) {
mdbx_error("meta[%u] has invalid magic/version %" PRIx64, meta_number,
page.mp_meta.mm_magic_and_version);
return ((page.mp_meta.mm_magic_and_version >> 8) != MDBX_MAGIC)
? MDBX_INVALID
: MDBX_VERSION_MISMATCH;
}
if (page.mp_pgno != meta_number) {
mdbx_error("meta[%u] has invalid pageno %" PRIaPGNO, meta_number,
page.mp_pgno);
return MDBX_INVALID;
}
if (page.mp_flags != P_META) {
mdbx_error("page #%u not a meta-page", meta_number);
return MDBX_INVALID;
}
if (!retryleft) {
mdbx_error("meta[%u] is too volatile, skip it", meta_number);
continue;
}
/* LY: check pagesize */
if (!mdbx_is_power2(page.mp_meta.mm_psize) ||
page.mp_meta.mm_psize < MIN_PAGESIZE ||
page.mp_meta.mm_psize > MAX_PAGESIZE) {
mdbx_notice("meta[%u] has invalid pagesize (%u), skip it", meta_number,
page.mp_meta.mm_psize);
rc = mdbx_is_power2(page.mp_meta.mm_psize) ? MDBX_VERSION_MISMATCH
: MDBX_INVALID;
continue;
}
if (meta_number == 0 && guess_pagesize != page.mp_meta.mm_psize) {
meta->mm_psize = page.mp_meta.mm_psize;
mdbx_info("meta[%u] took pagesize %u", meta_number,
page.mp_meta.mm_psize);
}
if (page.mp_meta.mm_txnid_a != page.mp_meta.mm_txnid_b) {
mdbx_warning("meta[%u] not completely updated, skip it", meta_number);
continue;
}
/* LY: check signature as a checksum */
if (META_IS_STEADY(&page.mp_meta) &&
page.mp_meta.mm_datasync_sign != mdbx_meta_sign(&page.mp_meta)) {
mdbx_notice("meta[%u] has invalid steady-checksum (0x%" PRIx64
" != 0x%" PRIx64 "), skip it",
meta_number, page.mp_meta.mm_datasync_sign,
mdbx_meta_sign(&page.mp_meta));
continue;
}
mdbx_debug("read meta%" PRIaPGNO " = root %" PRIaPGNO "/%" PRIaPGNO
", geo %" PRIaPGNO "/%" PRIaPGNO "-%" PRIaPGNO "/%" PRIaPGNO
" +%u -%u, txn_id %" PRIaTXN ", %s",
page.mp_pgno, page.mp_meta.mm_dbs[MAIN_DBI].md_root,
page.mp_meta.mm_dbs[FREE_DBI].md_root, page.mp_meta.mm_geo.lower,
page.mp_meta.mm_geo.next, page.mp_meta.mm_geo.now,
page.mp_meta.mm_geo.upper, page.mp_meta.mm_geo.grow,
page.mp_meta.mm_geo.shrink, page.mp_meta.mm_txnid_a,
mdbx_durable_str(&page.mp_meta));
/* LY: check min-pages value */
if (page.mp_meta.mm_geo.lower < MIN_PAGENO ||
page.mp_meta.mm_geo.lower > MAX_PAGENO) {
mdbx_notice("meta[%u] has invalid min-pages (%" PRIaPGNO "), skip it",
meta_number, page.mp_meta.mm_geo.lower);
rc = MDBX_INVALID;
continue;
}
/* LY: check max-pages value */
if (page.mp_meta.mm_geo.upper < MIN_PAGENO ||
page.mp_meta.mm_geo.upper > MAX_PAGENO ||
page.mp_meta.mm_geo.upper < page.mp_meta.mm_geo.lower) {
mdbx_notice("meta[%u] has invalid max-pages (%" PRIaPGNO "), skip it",
meta_number, page.mp_meta.mm_geo.upper);
rc = MDBX_INVALID;
continue;
}
/* LY: check last_pgno */
if (page.mp_meta.mm_geo.next < MIN_PAGENO ||
page.mp_meta.mm_geo.next - 1 > MAX_PAGENO) {
mdbx_notice("meta[%u] has invalid next-pageno (%" PRIaPGNO "), skip it",
meta_number, page.mp_meta.mm_geo.next);
rc = MDBX_CORRUPTED;
continue;
}
/* LY: check filesize & used_bytes */
const uint64_t used_bytes =
page.mp_meta.mm_geo.next * (uint64_t)page.mp_meta.mm_psize;
if (used_bytes > *filesize) {
/* Here could be a race with DB-shrinking performed by other process */
rc = mdbx_filesize(env->me_fd, filesize);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
if (used_bytes > *filesize) {
mdbx_notice("meta[%u] used-bytes (%" PRIu64
") beyond filesize (%" PRIu64 "), skip it",
meta_number, used_bytes, *filesize);
rc = MDBX_CORRUPTED;
continue;
}
}
/* LY: check mapsize limits */
const uint64_t mapsize_min =
page.mp_meta.mm_geo.lower * (uint64_t)page.mp_meta.mm_psize;
STATIC_ASSERT(MAX_MAPSIZE < SSIZE_MAX - MAX_PAGESIZE);
STATIC_ASSERT(MIN_MAPSIZE < MAX_MAPSIZE);
if (mapsize_min < MIN_MAPSIZE || mapsize_min > MAX_MAPSIZE) {
mdbx_notice("meta[%u] has invalid min-mapsize (%" PRIu64 "), skip it",
meta_number, mapsize_min);
rc = MDBX_VERSION_MISMATCH;
continue;
}
const uint64_t mapsize_max =
page.mp_meta.mm_geo.upper * (uint64_t)page.mp_meta.mm_psize;
STATIC_ASSERT(MIN_MAPSIZE < MAX_MAPSIZE);
if (mapsize_max > MAX_MAPSIZE ||
MAX_PAGENO < mdbx_roundup2((size_t)mapsize_max, env->me_os_psize) /
(size_t)page.mp_meta.mm_psize) {
if (page.mp_meta.mm_geo.next - 1 > MAX_PAGENO ||
used_bytes > MAX_MAPSIZE) {
mdbx_notice("meta[%u] has too large max-mapsize (%" PRIu64 "), skip it",
meta_number, mapsize_max);
rc = MDBX_TOO_LARGE;
continue;
}
/* allow to open large DB from a 32-bit environment */
mdbx_notice("meta[%u] has too large max-mapsize (%" PRIu64 "), "
"but size of used space still acceptable (%" PRIu64 ")",
meta_number, mapsize_max, used_bytes);
page.mp_meta.mm_geo.upper = (pgno_t)(MAX_MAPSIZE / page.mp_meta.mm_psize);
}
/* LY: check and silently put mm_geo.now into [geo.lower...geo.upper].
*
* Copy-with-compaction by previous version of libmdbx could produce DB-file
* less than meta.geo.lower bound, in case actual filling is low or no data
* at all. This is not a problem as there is no damage or loss of data.
* Therefore it is better not to consider such situation as an error, but
* silently correct it. */
if (page.mp_meta.mm_geo.now < page.mp_meta.mm_geo.lower)
page.mp_meta.mm_geo.now = page.mp_meta.mm_geo.lower;
if (page.mp_meta.mm_geo.now > page.mp_meta.mm_geo.upper)
page.mp_meta.mm_geo.now = page.mp_meta.mm_geo.upper;
if (page.mp_meta.mm_geo.next > page.mp_meta.mm_geo.now) {
mdbx_notice("meta[%u] next-pageno (%" PRIaPGNO
") is beyond end-pgno (%" PRIaPGNO "), skip it",
meta_number, page.mp_meta.mm_geo.next,
page.mp_meta.mm_geo.now);
rc = MDBX_CORRUPTED;
continue;
}
/* LY: FreeDB root */
if (page.mp_meta.mm_dbs[FREE_DBI].md_root == P_INVALID) {
if (page.mp_meta.mm_dbs[FREE_DBI].md_branch_pages ||
page.mp_meta.mm_dbs[FREE_DBI].md_depth ||
page.mp_meta.mm_dbs[FREE_DBI].md_entries ||
page.mp_meta.mm_dbs[FREE_DBI].md_leaf_pages ||
page.mp_meta.mm_dbs[FREE_DBI].md_overflow_pages) {
mdbx_notice("meta[%u] has false-empty freedb, skip it", meta_number);
rc = MDBX_CORRUPTED;
continue;
}
} else if (page.mp_meta.mm_dbs[FREE_DBI].md_root >=
page.mp_meta.mm_geo.next) {
mdbx_notice("meta[%u] has invalid freedb-root %" PRIaPGNO ", skip it",
meta_number, page.mp_meta.mm_dbs[FREE_DBI].md_root);
rc = MDBX_CORRUPTED;
continue;
}
/* LY: MainDB root */
if (page.mp_meta.mm_dbs[MAIN_DBI].md_root == P_INVALID) {
if (page.mp_meta.mm_dbs[MAIN_DBI].md_branch_pages ||
page.mp_meta.mm_dbs[MAIN_DBI].md_depth ||
page.mp_meta.mm_dbs[MAIN_DBI].md_entries ||
page.mp_meta.mm_dbs[MAIN_DBI].md_leaf_pages ||
page.mp_meta.mm_dbs[MAIN_DBI].md_overflow_pages) {
mdbx_notice("meta[%u] has false-empty maindb", meta_number);
rc = MDBX_CORRUPTED;
continue;
}
} else if (page.mp_meta.mm_dbs[MAIN_DBI].md_root >=
page.mp_meta.mm_geo.next) {
mdbx_notice("meta[%u] has invalid maindb-root %" PRIaPGNO ", skip it",
meta_number, page.mp_meta.mm_dbs[MAIN_DBI].md_root);
rc = MDBX_CORRUPTED;
continue;
}
if (page.mp_meta.mm_txnid_a == 0) {
mdbx_warning("meta[%u] has zero txnid, skip it", meta_number);
continue;
}
if (mdbx_meta_ot(prefer_noweak, env, meta, &page.mp_meta)) {
*meta = page.mp_meta;
if (META_IS_WEAK(meta))
loop_limit += 1; /* LY: should re-read to hush race with update */
mdbx_info("latch meta[%u]", meta_number);
}
}
if (META_IS_WEAK(meta)) {
mdbx_error("no usable meta-pages, database is corrupted");
return rc;
}
return MDBX_SUCCESS;
}
static MDBX_page *__cold mdbx_meta_model(const MDBX_env *env, MDBX_page *model,
unsigned num) {
mdbx_ensure(env, mdbx_is_power2(env->me_psize));
mdbx_ensure(env, env->me_psize >= MIN_PAGESIZE);
mdbx_ensure(env, env->me_psize <= MAX_PAGESIZE);
mdbx_ensure(env, env->me_dbgeo.lower >= MIN_MAPSIZE);
mdbx_ensure(env, env->me_dbgeo.upper <= MAX_MAPSIZE);
mdbx_ensure(env, env->me_dbgeo.now >= env->me_dbgeo.lower);
mdbx_ensure(env, env->me_dbgeo.now <= env->me_dbgeo.upper);
memset(model, 0, sizeof(*model));
model->mp_pgno = num;
model->mp_flags = P_META;
model->mp_meta.mm_magic_and_version = MDBX_DATA_MAGIC;
model->mp_meta.mm_geo.lower = bytes2pgno(env, env->me_dbgeo.lower);
model->mp_meta.mm_geo.upper = bytes2pgno(env, env->me_dbgeo.upper);
model->mp_meta.mm_geo.grow = (uint16_t)bytes2pgno(env, env->me_dbgeo.grow);
model->mp_meta.mm_geo.shrink =
(uint16_t)bytes2pgno(env, env->me_dbgeo.shrink);
model->mp_meta.mm_geo.now = bytes2pgno(env, env->me_dbgeo.now);
model->mp_meta.mm_geo.next = NUM_METAS;
mdbx_ensure(env, model->mp_meta.mm_geo.lower >= MIN_PAGENO);
mdbx_ensure(env, model->mp_meta.mm_geo.upper <= MAX_PAGENO);
mdbx_ensure(env, model->mp_meta.mm_geo.now >= model->mp_meta.mm_geo.lower);
mdbx_ensure(env, model->mp_meta.mm_geo.now <= model->mp_meta.mm_geo.upper);
mdbx_ensure(env, model->mp_meta.mm_geo.next >= MIN_PAGENO);
mdbx_ensure(env, model->mp_meta.mm_geo.next <= model->mp_meta.mm_geo.now);
mdbx_ensure(env, model->mp_meta.mm_geo.grow ==
bytes2pgno(env, env->me_dbgeo.grow));
mdbx_ensure(env, model->mp_meta.mm_geo.shrink ==
bytes2pgno(env, env->me_dbgeo.shrink));
model->mp_meta.mm_psize = env->me_psize;
model->mp_meta.mm_flags = (uint16_t)env->me_flags;
model->mp_meta.mm_flags |=
MDBX_INTEGERKEY; /* this is mm_dbs[FREE_DBI].md_flags */
model->mp_meta.mm_dbs[FREE_DBI].md_root = P_INVALID;
model->mp_meta.mm_dbs[MAIN_DBI].md_root = P_INVALID;
mdbx_meta_set_txnid(env, &model->mp_meta, MIN_TXNID + num);
model->mp_meta.mm_datasync_sign = mdbx_meta_sign(&model->mp_meta);
return (MDBX_page *)((uint8_t *)model + env->me_psize);
}
/* Fill in most of the zeroed meta-pages for an empty database environment.
* Return pointer to recenly (head) meta-page. */
static MDBX_page *__cold mdbx_init_metas(const MDBX_env *env, void *buffer) {
MDBX_page *page0 = (MDBX_page *)buffer;
MDBX_page *page1 = mdbx_meta_model(env, page0, 0);
MDBX_page *page2 = mdbx_meta_model(env, page1, 1);
mdbx_meta_model(env, page2, 2);
mdbx_assert(env, !mdbx_meta_eq(env, &page0->mp_meta, &page1->mp_meta));
mdbx_assert(env, !mdbx_meta_eq(env, &page1->mp_meta, &page2->mp_meta));
mdbx_assert(env, !mdbx_meta_eq(env, &page2->mp_meta, &page0->mp_meta));
return page2;
}
static int mdbx_sync_locked(MDBX_env *env, unsigned flags,
MDBX_meta *const pending) {
mdbx_assert(env, ((env->me_flags ^ flags) & MDBX_WRITEMAP) == 0);
MDBX_meta *const meta0 = METAPAGE(env, 0);
MDBX_meta *const meta1 = METAPAGE(env, 1);
MDBX_meta *const meta2 = METAPAGE(env, 2);
MDBX_meta *const head = mdbx_meta_head(env);
mdbx_assert(env, mdbx_meta_eq_mask(env) == 0);
mdbx_assert(env,
pending < METAPAGE(env, 0) || pending > METAPAGE(env, NUM_METAS));
mdbx_assert(env, (env->me_flags & (MDBX_RDONLY | MDBX_FATAL_ERROR)) == 0);
mdbx_assert(env, !META_IS_STEADY(head) || env->me_sync_pending != 0);
mdbx_assert(env, pending->mm_geo.next <= pending->mm_geo.now);
const size_t usedbytes = pgno_align2os_bytes(env, pending->mm_geo.next);
if (env->me_sync_threshold && env->me_sync_pending >= env->me_sync_threshold)
flags &= MDBX_WRITEMAP | MDBX_SHRINK_ALLOWED; /* force steady */
/* LY: check conditions to shrink datafile */
const pgno_t backlog_gap =
pending->mm_dbs[FREE_DBI].md_depth + mdbx_backlog_extragap(env);
pgno_t shrink = 0;
if ((flags & MDBX_SHRINK_ALLOWED) && pending->mm_geo.shrink &&
pending->mm_geo.now - pending->mm_geo.next >
pending->mm_geo.shrink + backlog_gap) {
const pgno_t aligner =
pending->mm_geo.grow ? pending->mm_geo.grow : pending->mm_geo.shrink;
const pgno_t with_backlog_gap = pending->mm_geo.next + backlog_gap;
const pgno_t aligned = pgno_align2os_pgno(
env, with_backlog_gap + aligner - with_backlog_gap % aligner);
const pgno_t bottom =
(aligned > pending->mm_geo.lower) ? aligned : pending->mm_geo.lower;
if (pending->mm_geo.now > bottom) {
flags &= MDBX_WRITEMAP | MDBX_SHRINK_ALLOWED; /* force steady */
shrink = pending->mm_geo.now - bottom;
pending->mm_geo.now = bottom;
if (mdbx_meta_txnid_stable(env, head) == pending->mm_txnid_a)
mdbx_meta_set_txnid(env, pending, pending->mm_txnid_a + 1);
}
}
/* LY: step#1 - sync previously written/updated data-pages */
int rc = MDBX_RESULT_TRUE;
if (env->me_sync_pending && (flags & MDBX_NOSYNC) == 0) {
mdbx_assert(env, ((flags ^ env->me_flags) & MDBX_WRITEMAP) == 0);
MDBX_meta *const steady = mdbx_meta_steady(env);
if (flags & MDBX_WRITEMAP) {
rc = mdbx_msync(&env->me_dxb_mmap, 0, usedbytes, flags & MDBX_MAPASYNC);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
if ((flags & MDBX_MAPASYNC) == 0) {
if (unlikely(pending->mm_geo.next > steady->mm_geo.now)) {
rc = mdbx_filesize_sync(env->me_fd);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
}
env->me_sync_pending = 0;
}
} else {
rc = mdbx_filesync(env->me_fd, pending->mm_geo.next > steady->mm_geo.now);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
env->me_sync_pending = 0;
}
}
/* Steady or Weak */
if (env->me_sync_pending == 0) {
pending->mm_datasync_sign = mdbx_meta_sign(pending);
} else {
pending->mm_datasync_sign =
(flags & MDBX_UTTERLY_NOSYNC) == MDBX_UTTERLY_NOSYNC
? MDBX_DATASIGN_NONE
: MDBX_DATASIGN_WEAK;
}
MDBX_meta *target = nullptr;
if (mdbx_meta_txnid_stable(env, head) == pending->mm_txnid_a) {
mdbx_assert(env, memcmp(&head->mm_dbs, &pending->mm_dbs,
sizeof(head->mm_dbs)) == 0);
mdbx_assert(env, memcmp(&head->mm_canary, &pending->mm_canary,
sizeof(head->mm_canary)) == 0);
mdbx_assert(env, memcmp(&head->mm_geo, &pending->mm_geo,
sizeof(pending->mm_geo)) == 0);
if (!META_IS_STEADY(head) && META_IS_STEADY(pending))
target = head;
else {
mdbx_ensure(env, mdbx_meta_eq(env, head, pending));
mdbx_debug("skip update meta");
return MDBX_SUCCESS;
}
} else if (head == meta0)
target = mdbx_meta_ancient(prefer_steady, env, meta1, meta2);
else if (head == meta1)
target = mdbx_meta_ancient(prefer_steady, env, meta0, meta2);
else {
mdbx_assert(env, head == meta2);
target = mdbx_meta_ancient(prefer_steady, env, meta0, meta1);
}
/* LY: step#2 - update meta-page. */
mdbx_debug("writing meta%" PRIaPGNO " = root %" PRIaPGNO "/%" PRIaPGNO
", geo %" PRIaPGNO "/%" PRIaPGNO "-%" PRIaPGNO "/%" PRIaPGNO
" +%u -%u, txn_id %" PRIaTXN ", %s",
container_of(target, MDBX_page, mp_data)->mp_pgno,
pending->mm_dbs[MAIN_DBI].md_root,
pending->mm_dbs[FREE_DBI].md_root, pending->mm_geo.lower,
pending->mm_geo.next, pending->mm_geo.now, pending->mm_geo.upper,
pending->mm_geo.grow, pending->mm_geo.shrink, pending->mm_txnid_a,
mdbx_durable_str(pending));
mdbx_debug("meta0: %s, %s, txn_id %" PRIaTXN ", root %" PRIaPGNO
"/%" PRIaPGNO,
(meta0 == head) ? "head" : (meta0 == target) ? "tail" : "stay",
mdbx_durable_str(meta0), mdbx_meta_txnid_fluid(env, meta0),
meta0->mm_dbs[MAIN_DBI].md_root, meta0->mm_dbs[FREE_DBI].md_root);
mdbx_debug("meta1: %s, %s, txn_id %" PRIaTXN ", root %" PRIaPGNO
"/%" PRIaPGNO,
(meta1 == head) ? "head" : (meta1 == target) ? "tail" : "stay",
mdbx_durable_str(meta1), mdbx_meta_txnid_fluid(env, meta1),
meta1->mm_dbs[MAIN_DBI].md_root, meta1->mm_dbs[FREE_DBI].md_root);
mdbx_debug("meta2: %s, %s, txn_id %" PRIaTXN ", root %" PRIaPGNO
"/%" PRIaPGNO,
(meta2 == head) ? "head" : (meta2 == target) ? "tail" : "stay",
mdbx_durable_str(meta2), mdbx_meta_txnid_fluid(env, meta2),
meta2->mm_dbs[MAIN_DBI].md_root, meta2->mm_dbs[FREE_DBI].md_root);
mdbx_assert(env, !mdbx_meta_eq(env, pending, meta0));
mdbx_assert(env, !mdbx_meta_eq(env, pending, meta1));
mdbx_assert(env, !mdbx_meta_eq(env, pending, meta2));
mdbx_assert(env, ((env->me_flags ^ flags) & MDBX_WRITEMAP) == 0);
mdbx_ensure(env, target == head || mdbx_meta_txnid_stable(env, target) <
pending->mm_txnid_a);
if (env->me_flags & MDBX_WRITEMAP) {
mdbx_jitter4testing(true);
if (likely(target != head)) {
/* LY: 'invalidate' the meta. */
target->mm_datasync_sign = MDBX_DATASIGN_WEAK;
mdbx_meta_update_begin(env, target, pending->mm_txnid_a);
#ifndef NDEBUG
/* debug: provoke failure to catch a violators, but don't touch mm_psize
* and mm_flags to allow readers catch actual pagesize. */
uint8_t *provoke_begin = (uint8_t *)&target->mm_dbs[FREE_DBI].md_root;
uint8_t *provoke_end = (uint8_t *)&target->mm_datasync_sign;
memset(provoke_begin, 0xCC, provoke_end - provoke_begin);
mdbx_jitter4testing(false);
#endif
/* LY: update info */
target->mm_geo = pending->mm_geo;
target->mm_dbs[FREE_DBI] = pending->mm_dbs[FREE_DBI];
target->mm_dbs[MAIN_DBI] = pending->mm_dbs[MAIN_DBI];
target->mm_canary = pending->mm_canary;
mdbx_jitter4testing(true);
mdbx_coherent_barrier();
/* LY: 'commit' the meta */
mdbx_meta_update_end(env, target, pending->mm_txnid_b);
mdbx_jitter4testing(true);
} else {
/* dangerous case (target == head), only mm_datasync_sign could
* me updated, check assertions once again */
mdbx_ensure(env,
mdbx_meta_txnid_stable(env, head) == pending->mm_txnid_a &&
!META_IS_STEADY(head) && META_IS_STEADY(pending));
mdbx_ensure(env, memcmp(&head->mm_geo, &pending->mm_geo,
sizeof(head->mm_geo)) == 0);
mdbx_ensure(env, memcmp(&head->mm_dbs, &pending->mm_dbs,
sizeof(head->mm_dbs)) == 0);
mdbx_ensure(env, memcmp(&head->mm_canary, &pending->mm_canary,
sizeof(head->mm_canary)) == 0);
}
target->mm_datasync_sign = pending->mm_datasync_sign;
mdbx_coherent_barrier();
mdbx_jitter4testing(true);
} else {
rc = mdbx_pwrite(env->me_fd, pending, sizeof(MDBX_meta),
(uint8_t *)target - env->me_map);
if (unlikely(rc != MDBX_SUCCESS)) {
undo:
mdbx_debug("write failed, disk error?");
/* On a failure, the pagecache still contains the new data.
* Try write some old data back, to prevent it from being used. */
mdbx_pwrite(env->me_fd, (void *)target, sizeof(MDBX_meta),
(uint8_t *)target - env->me_map);
goto fail;
}
mdbx_invalidate_cache(target, sizeof(MDBX_meta));
}
/* LY: step#3 - sync meta-pages. */
mdbx_assert(env, ((env->me_flags ^ flags) & MDBX_WRITEMAP) == 0);
if ((flags & (MDBX_NOSYNC | MDBX_NOMETASYNC)) == 0) {
mdbx_assert(env, ((flags ^ env->me_flags) & MDBX_WRITEMAP) == 0);
if (flags & MDBX_WRITEMAP) {
const size_t offset =
((uint8_t *)container_of(head, MDBX_page, mp_meta)) -
env->me_dxb_mmap.dxb;
const size_t paged_offset = offset & ~(env->me_os_psize - 1);
const size_t paged_length = mdbx_roundup2(
env->me_psize + offset - paged_offset, env->me_os_psize);
rc = mdbx_msync(&env->me_dxb_mmap, paged_offset, paged_length,
flags & MDBX_MAPASYNC);
if (unlikely(rc != MDBX_SUCCESS))
goto fail;
} else {
rc = mdbx_filesync(env->me_fd, false);
if (rc != MDBX_SUCCESS)
goto undo;
}
}
/* LY: shrink datafile if needed */
if (unlikely(shrink)) {
mdbx_info("shrink to %" PRIaPGNO " pages (-%" PRIaPGNO ")",
pending->mm_geo.now, shrink);
rc = mdbx_mapresize(env, pending->mm_geo.now, pending->mm_geo.upper);
if (MDBX_IS_ERROR(rc))
goto fail;
}
return MDBX_SUCCESS;
fail:
env->me_flags |= MDBX_FATAL_ERROR;
return rc;
}
int __cold mdbx_env_get_maxkeysize(MDBX_env *env) {
if (!env || env->me_signature != MDBX_ME_SIGNATURE || !env->me_maxkey_limit)
return (MDBX_EINVAL > 0) ? -MDBX_EINVAL : MDBX_EINVAL;
return env->me_maxkey_limit;
}
#define mdbx_nodemax(pagesize) \
(((((pagesize)-PAGEHDRSZ) / MDBX_MINKEYS) & ~(uintptr_t)1) - sizeof(indx_t))
#define mdbx_maxkey(nodemax) (((nodemax)-NODESIZE - sizeof(MDBX_db)) / 2)
#define mdbx_maxgc_ov1page(pagesize) \
(((pagesize)-PAGEHDRSZ) / sizeof(pgno_t) - 1)
static void __cold mdbx_setup_pagesize(MDBX_env *env, const size_t pagesize) {
STATIC_ASSERT(SSIZE_MAX > MAX_MAPSIZE);
STATIC_ASSERT(MIN_PAGESIZE > sizeof(MDBX_page));
mdbx_ensure(env, mdbx_is_power2(pagesize));
mdbx_ensure(env, pagesize >= MIN_PAGESIZE);
mdbx_ensure(env, pagesize <= MAX_PAGESIZE);
env->me_psize = (unsigned)pagesize;
STATIC_ASSERT(mdbx_maxgc_ov1page(MIN_PAGESIZE) > 42);
STATIC_ASSERT(mdbx_maxgc_ov1page(MAX_PAGESIZE) < MDBX_DPL_TXNFULL);
const intptr_t maxgc_ov1page = (pagesize - PAGEHDRSZ) / sizeof(pgno_t) - 1;
mdbx_ensure(env,
maxgc_ov1page > 42 && maxgc_ov1page < (intptr_t)MDBX_DPL_TXNFULL);
env->me_maxgc_ov1page = (unsigned)maxgc_ov1page;
STATIC_ASSERT(mdbx_nodemax(MIN_PAGESIZE) > 42);
STATIC_ASSERT(mdbx_nodemax(MAX_PAGESIZE) < UINT16_MAX);
const intptr_t nodemax = mdbx_nodemax(pagesize);
mdbx_ensure(env, nodemax > 42 && nodemax < UINT16_MAX && nodemax % 2 == 0);
env->me_nodemax = (unsigned)nodemax;
STATIC_ASSERT(mdbx_maxkey(MIN_PAGESIZE) > 42);
STATIC_ASSERT(mdbx_maxkey(MIN_PAGESIZE) < MIN_PAGESIZE);
STATIC_ASSERT(mdbx_maxkey(MAX_PAGESIZE) > 42);
STATIC_ASSERT(mdbx_maxkey(MAX_PAGESIZE) < MAX_PAGESIZE);
const intptr_t maxkey_limit = mdbx_maxkey(env->me_nodemax);
mdbx_ensure(env, maxkey_limit > 42 && (size_t)maxkey_limit < pagesize &&
maxkey_limit % 2 == 0);
env->me_maxkey_limit = (unsigned)maxkey_limit;
env->me_psize2log = mdbx_log2(pagesize);
mdbx_assert(env, pgno2bytes(env, 1) == pagesize);
mdbx_assert(env, bytes2pgno(env, pagesize + pagesize) == 2);
}
int __cold mdbx_env_create(MDBX_env **penv) {
MDBX_env *env = mdbx_calloc(1, sizeof(MDBX_env));
if (!env)
return MDBX_ENOMEM;
env->me_maxreaders = DEFAULT_READERS;
env->me_maxdbs = env->me_numdbs = CORE_DBS;
env->me_fd = INVALID_HANDLE_VALUE;
env->me_lfd = INVALID_HANDLE_VALUE;
env->me_pid = mdbx_getpid();
int rc;
const size_t os_psize = mdbx_syspagesize();
if (!mdbx_is_power2(os_psize) || os_psize < MIN_PAGESIZE) {
mdbx_error("unsuitable system pagesize %" PRIuPTR, os_psize);
rc = MDBX_INCOMPATIBLE;
goto bailout;
}
env->me_os_psize = (unsigned)os_psize;
mdbx_setup_pagesize(env, env->me_os_psize);
rc = mdbx_fastmutex_init(&env->me_dbi_lock);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
#if defined(_WIN32) || defined(_WIN64)
mdbx_srwlock_Init(&env->me_remap_guard);
InitializeCriticalSection(&env->me_windowsbug_lock);
#else
rc = mdbx_fastmutex_init(&env->me_remap_guard);
if (unlikely(rc != MDBX_SUCCESS)) {
mdbx_fastmutex_destroy(&env->me_dbi_lock);
goto bailout;
}
rc = mdbx_fastmutex_init(&env->me_lckless_wmutex);
if (unlikely(rc != MDBX_SUCCESS)) {
mdbx_fastmutex_destroy(&env->me_remap_guard);
mdbx_fastmutex_destroy(&env->me_dbi_lock);
goto bailout;
}
#endif /* Windows */
VALGRIND_CREATE_MEMPOOL(env, 0, 0);
env->me_signature = MDBX_ME_SIGNATURE;
*penv = env;
return MDBX_SUCCESS;
bailout:
mdbx_free(env);
*penv = nullptr;
return rc;
}
static int __cold mdbx_env_map(MDBX_env *env, size_t usedsize) {
int rc = mdbx_mmap(env->me_flags, &env->me_dxb_mmap, env->me_dbgeo.now,
env->me_dbgeo.upper);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
#ifdef MADV_DONTFORK
if (madvise(env->me_map, env->me_mapsize, MADV_DONTFORK))
return errno;
#endif
#ifdef MADV_NOHUGEPAGE
(void)madvise(env->me_map, env->me_mapsize, MADV_NOHUGEPAGE);
#endif
#if defined(MADV_DODUMP) && defined(MADV_DONTDUMP)
const size_t meta_length = pgno2bytes(env, NUM_METAS);
(void)madvise(env->me_map, meta_length, MADV_DODUMP);
if (!(env->me_flags & MDBX_PAGEPERTURB))
(void)madvise(env->me_map + meta_length, env->me_mapsize - meta_length,
MADV_DONTDUMP);
#endif
#ifdef MADV_REMOVE
if (usedsize && (env->me_flags & MDBX_WRITEMAP)) {
(void)madvise(env->me_map + usedsize, env->me_mapsize - usedsize,
MADV_REMOVE);
}
#else
(void)usedsize;
#endif
#if defined(MADV_RANDOM) && defined(MADV_WILLNEED)
/* Turn on/off readahead. It's harmful when the DB is larger than RAM. */
if (madvise(env->me_map, env->me_mapsize,
(env->me_flags & MDBX_NORDAHEAD) ? MADV_RANDOM : MADV_WILLNEED))
return errno;
#endif
#ifdef USE_VALGRIND
env->me_valgrind_handle =
VALGRIND_CREATE_BLOCK(env->me_map, env->me_mapsize, "mdbx");
#endif
return MDBX_SUCCESS;
}
__cold LIBMDBX_API int
mdbx_env_set_geometry(MDBX_env *env, intptr_t size_lower, intptr_t size_now,
intptr_t size_upper, intptr_t growth_step,
intptr_t shrink_threshold, intptr_t pagesize) {
if (unlikely(!env))
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(env->me_pid != mdbx_getpid()))
env->me_flags |= MDBX_FATAL_ERROR;
if (unlikely(env->me_flags & MDBX_FATAL_ERROR))
return MDBX_PANIC;
const bool inside_txn =
(env->me_txn0 && env->me_txn0->mt_owner == mdbx_thread_self());
#if MDBX_DEBUG
if (growth_step < 0)
growth_step = 1;
if (shrink_threshold < 0)
shrink_threshold = 1;
#endif
bool need_unlock = false;
int rc = MDBX_PROBLEM;
if (env->me_map) {
/* env already mapped */
if (!env->me_lck || (env->me_flags & MDBX_RDONLY))
return MDBX_EACCESS;
if (!inside_txn) {
int err = mdbx_txn_lock(env, false);
if (unlikely(err != MDBX_SUCCESS))
return err;
need_unlock = true;
}
MDBX_meta *head = mdbx_meta_head(env);
if (pagesize < 0)
pagesize = env->me_psize;
if (pagesize != (intptr_t)env->me_psize) {
rc = MDBX_EINVAL;
goto bailout;
}
if (size_lower < 0)
size_lower = pgno2bytes(env, head->mm_geo.lower);
if (size_now < 0)
size_now = pgno2bytes(env, head->mm_geo.now);
if (size_upper < 0)
size_upper = pgno2bytes(env, head->mm_geo.upper);
if (growth_step < 0)
growth_step = pgno2bytes(env, head->mm_geo.grow);
if (shrink_threshold < 0)
shrink_threshold = pgno2bytes(env, head->mm_geo.shrink);
const size_t usedbytes = pgno2bytes(env, head->mm_geo.next);
if ((size_t)size_upper < usedbytes) {
rc = MDBX_MAP_FULL;
goto bailout;
}
if ((size_t)size_now < usedbytes)
size_now = usedbytes;
} else {
/* env NOT yet mapped */
if (unlikely(inside_txn))
return MDBX_PANIC;
if (pagesize < 0) {
pagesize = env->me_os_psize;
if ((uintptr_t)pagesize > MAX_PAGESIZE)
pagesize = MAX_PAGESIZE;
mdbx_assert(env, (uintptr_t)pagesize >= MIN_PAGESIZE);
}
}
if (pagesize == 0)
pagesize = MIN_PAGESIZE;
else if (pagesize == INTPTR_MAX)
pagesize = MAX_PAGESIZE;
if (pagesize < (intptr_t)MIN_PAGESIZE || pagesize > (intptr_t)MAX_PAGESIZE ||
!mdbx_is_power2(pagesize)) {
rc = MDBX_EINVAL;
goto bailout;
}
if (size_lower <= 0) {
size_lower = MIN_MAPSIZE;
if (MIN_MAPSIZE / pagesize < MIN_PAGENO)
size_lower = MIN_PAGENO * pagesize;
}
if (size_now <= 0) {
size_now = DEFAULT_MAPSIZE;
if (size_now < size_lower)
size_now = size_lower;
if (size_upper >= size_lower && size_now > size_upper)
size_now = size_upper;
}
if (size_upper <= 0) {
if ((size_t)size_now >= MAX_MAPSIZE / 2)
size_upper = MAX_MAPSIZE;
else if (MAX_MAPSIZE != MAX_MAPSIZE32 &&
(size_t)size_now >= MAX_MAPSIZE32 / 2 &&
(size_t)size_now <= MAX_MAPSIZE32 / 4 * 3)
size_upper = MAX_MAPSIZE32;
else {
size_upper = size_now + size_now;
if ((size_t)size_upper < DEFAULT_MAPSIZE * 2)
size_upper = DEFAULT_MAPSIZE * 2;
}
if ((size_t)size_upper / pagesize > MAX_PAGENO)
size_upper = pagesize * MAX_PAGENO;
}
if (unlikely(size_lower < (intptr_t)MIN_MAPSIZE || size_lower > size_upper)) {
rc = MDBX_EINVAL;
goto bailout;
}
if ((uint64_t)size_lower / pagesize < MIN_PAGENO) {
rc = MDBX_EINVAL;
goto bailout;
}
if (unlikely((size_t)size_upper > MAX_MAPSIZE ||
(uint64_t)size_upper / pagesize > MAX_PAGENO)) {
rc = MDBX_TOO_LARGE;
goto bailout;
}
size_lower = mdbx_roundup2(size_lower, env->me_os_psize);
size_upper = mdbx_roundup2(size_upper, env->me_os_psize);
size_now = mdbx_roundup2(size_now, env->me_os_psize);
/* LY: подбираем значение size_upper:
* - кратное размеру системной страницы
* - без нарушения MAX_MAPSIZE или MAX_PAGENO */
while (unlikely((size_t)size_upper > MAX_MAPSIZE ||
(uint64_t)size_upper / pagesize > MAX_PAGENO)) {
if ((size_t)size_upper < env->me_os_psize + MIN_MAPSIZE ||
(size_t)size_upper < env->me_os_psize * (MIN_PAGENO + 1)) {
/* паранойа на случай переполнения при невероятных значениях */
rc = MDBX_EINVAL;
goto bailout;
}
size_upper -= env->me_os_psize;
if ((size_t)size_upper < (size_t)size_lower)
size_lower = size_upper;
}
mdbx_assert(env, (size_upper - size_lower) % env->me_os_psize == 0);
if (size_now < size_lower)
size_now = size_lower;
if (size_now > size_upper)
size_now = size_upper;
if (growth_step < 0) {
growth_step = ((size_t)(size_upper - size_lower)) / 42;
if (growth_step > size_lower)
growth_step = size_lower;
if (growth_step < 65536)
growth_step = 65536;
if ((size_t)growth_step > MEGABYTE * 16)
growth_step = MEGABYTE * 16;
}
growth_step = mdbx_roundup2(growth_step, env->me_os_psize);
if (bytes2pgno(env, growth_step) > UINT16_MAX)
growth_step = pgno2bytes(env, UINT16_MAX);
if (shrink_threshold < 0) {
shrink_threshold = growth_step + growth_step;
if (shrink_threshold < growth_step)
shrink_threshold = growth_step;
}
shrink_threshold = mdbx_roundup2(shrink_threshold, env->me_os_psize);
if (bytes2pgno(env, shrink_threshold) > UINT16_MAX)
shrink_threshold = pgno2bytes(env, UINT16_MAX);
/* save user's geo-params for future open/create */
env->me_dbgeo.lower = size_lower;
env->me_dbgeo.now = size_now;
env->me_dbgeo.upper = size_upper;
env->me_dbgeo.grow = growth_step;
env->me_dbgeo.shrink = shrink_threshold;
rc = MDBX_SUCCESS;
if (env->me_map) {
/* apply new params */
mdbx_assert(env, pagesize == (intptr_t)env->me_psize);
MDBX_meta *head = mdbx_meta_head(env);
MDBX_meta meta = *head;
meta.mm_geo.lower = bytes2pgno(env, env->me_dbgeo.lower);
meta.mm_geo.now = bytes2pgno(env, env->me_dbgeo.now);
meta.mm_geo.upper = bytes2pgno(env, env->me_dbgeo.upper);
meta.mm_geo.grow = (uint16_t)bytes2pgno(env, env->me_dbgeo.grow);
meta.mm_geo.shrink = (uint16_t)bytes2pgno(env, env->me_dbgeo.shrink);
mdbx_assert(env, env->me_dbgeo.lower >= MIN_MAPSIZE);
mdbx_assert(env, meta.mm_geo.lower >= MIN_PAGENO);
mdbx_assert(env, env->me_dbgeo.upper <= MAX_MAPSIZE);
mdbx_assert(env, meta.mm_geo.upper <= MAX_PAGENO);
mdbx_assert(env, meta.mm_geo.now >= meta.mm_geo.next);
mdbx_assert(env, env->me_dbgeo.upper >= env->me_dbgeo.lower);
mdbx_assert(env, meta.mm_geo.upper >= meta.mm_geo.now);
mdbx_assert(env, meta.mm_geo.now >= meta.mm_geo.lower);
mdbx_assert(env, meta.mm_geo.grow == bytes2pgno(env, env->me_dbgeo.grow));
mdbx_assert(env,
meta.mm_geo.shrink == bytes2pgno(env, env->me_dbgeo.shrink));
if (memcmp(&meta.mm_geo, &head->mm_geo, sizeof(meta.mm_geo))) {
#if defined(_WIN32) || defined(_WIN64)
/* Was DB shrinking disabled before and now it will be enabled? */
if (meta.mm_geo.lower < meta.mm_geo.upper && meta.mm_geo.shrink &&
!(head->mm_geo.lower < head->mm_geo.upper && head->mm_geo.shrink)) {
rc = mdbx_rdt_lock(env);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
/* Check if there are any reading threads that do not use the SRWL */
const mdbx_pid_t CurrentTid = GetCurrentThreadId();
const MDBX_reader *const begin = env->me_lck->mti_readers;
const MDBX_reader *const end = begin + env->me_lck->mti_numreaders;
for (const MDBX_reader *reader = begin; reader < end; ++reader) {
if (reader->mr_pid == env->me_pid && reader->mr_tid &&
reader->mr_tid != CurrentTid) {
/* At least one thread may don't use SRWL */
rc = MDBX_EPERM;
break;
}
}
mdbx_rdt_unlock(env);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
}
#endif
if (meta.mm_geo.now != head->mm_geo.now ||
meta.mm_geo.upper != head->mm_geo.upper) {
rc = mdbx_mapresize(env, meta.mm_geo.now, meta.mm_geo.upper);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
head = /* base address could be changed */ mdbx_meta_head(env);
}
env->me_sync_pending += env->me_psize;
mdbx_meta_set_txnid(env, &meta, mdbx_meta_txnid_stable(env, head) + 1);
rc = mdbx_sync_locked(env, env->me_flags, &meta);
}
} else if (pagesize != (intptr_t)env->me_psize) {
mdbx_setup_pagesize(env, pagesize);
}
bailout:
if (need_unlock)
mdbx_txn_unlock(env);
return rc;
}
int __cold mdbx_env_set_mapsize(MDBX_env *env, size_t size) {
return mdbx_env_set_geometry(env, -1, size, -1, -1, -1, -1);
}
int __cold mdbx_env_set_maxdbs(MDBX_env *env, MDBX_dbi dbs) {
if (unlikely(dbs > MAX_DBI))
return MDBX_EINVAL;
if (unlikely(!env))
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(env->me_map))
return MDBX_EPERM;
env->me_maxdbs = dbs + CORE_DBS;
return MDBX_SUCCESS;
}
int __cold mdbx_env_set_maxreaders(MDBX_env *env, unsigned readers) {
if (unlikely(readers < 1 || readers > INT16_MAX))
return MDBX_EINVAL;
if (unlikely(!env))
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(env->me_map))
return MDBX_EPERM;
env->me_maxreaders = readers;
return MDBX_SUCCESS;
}
int __cold mdbx_env_get_maxreaders(MDBX_env *env, unsigned *readers) {
if (!env || !readers)
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
*readers = env->me_maxreaders;
return MDBX_SUCCESS;
}
/* Further setup required for opening an MDBX environment */
static int __cold mdbx_setup_dxb(MDBX_env *env, int lck_rc) {
uint64_t filesize_before_mmap;
MDBX_meta meta;
int rc = MDBX_RESULT_FALSE;
int err = mdbx_read_header(env, &meta, &filesize_before_mmap);
if (unlikely(err != MDBX_SUCCESS)) {
if (lck_rc != /* lck exclusive */ MDBX_RESULT_TRUE || err != MDBX_ENODATA ||
(env->me_flags & MDBX_RDONLY) != 0)
return err;
mdbx_debug("create new database");
rc = /* new database */ MDBX_RESULT_TRUE;
if (!env->me_dbgeo.now) {
/* set defaults if not configured */
err = mdbx_env_set_mapsize(env, DEFAULT_MAPSIZE);
if (unlikely(err != MDBX_SUCCESS))
return err;
}
void *buffer = mdbx_calloc(NUM_METAS, env->me_psize);
if (!buffer)
return MDBX_ENOMEM;
meta = mdbx_init_metas(env, buffer)->mp_meta;
err = mdbx_pwrite(env->me_fd, buffer, env->me_psize * NUM_METAS, 0);
mdbx_free(buffer);
if (unlikely(err != MDBX_SUCCESS))
return err;
err = mdbx_ftruncate(env->me_fd, filesize_before_mmap = env->me_dbgeo.now);
if (unlikely(err != MDBX_SUCCESS))
return err;
#ifndef NDEBUG /* just for checking */
err = mdbx_read_header(env, &meta, &filesize_before_mmap);
if (unlikely(err != MDBX_SUCCESS))
return err;
#endif
}
mdbx_info("header: root %" PRIaPGNO "/%" PRIaPGNO ", geo %" PRIaPGNO
"/%" PRIaPGNO "-%" PRIaPGNO "/%" PRIaPGNO
" +%u -%u, txn_id %" PRIaTXN ", %s",
meta.mm_dbs[MAIN_DBI].md_root, meta.mm_dbs[FREE_DBI].md_root,
meta.mm_geo.lower, meta.mm_geo.next, meta.mm_geo.now,
meta.mm_geo.upper, meta.mm_geo.grow, meta.mm_geo.shrink,
meta.mm_txnid_a, mdbx_durable_str(&meta));
mdbx_setup_pagesize(env, meta.mm_psize);
const size_t used_bytes = pgno2bytes(env, meta.mm_geo.next);
if ((env->me_flags & MDBX_RDONLY) /* readonly */
|| lck_rc != MDBX_RESULT_TRUE /* not exclusive */) {
/* use present params from db */
err = mdbx_env_set_geometry(
env, meta.mm_geo.lower * (uint64_t)meta.mm_psize,
meta.mm_geo.now * (uint64_t)meta.mm_psize,
meta.mm_geo.upper * (uint64_t)meta.mm_psize,
meta.mm_geo.grow * (uint64_t)meta.mm_psize,
meta.mm_geo.shrink * (uint64_t)meta.mm_psize, meta.mm_psize);
if (unlikely(err != MDBX_SUCCESS)) {
mdbx_error("could not use present dbsize-params from db");
return MDBX_INCOMPATIBLE;
}
} else if (env->me_dbgeo.now) {
/* silently growth to last used page */
if (env->me_dbgeo.now < used_bytes)
env->me_dbgeo.now = used_bytes;
if (env->me_dbgeo.upper < used_bytes)
env->me_dbgeo.upper = used_bytes;
/* apply preconfigured params, but only if substantial changes:
* - upper or lower limit changes
* - shrink threshold or growth step
* But ignore just chagne just a 'now/current' size. */
if (bytes_align2os_bytes(env, env->me_dbgeo.upper) !=
pgno_align2os_bytes(env, meta.mm_geo.upper) ||
bytes_align2os_bytes(env, env->me_dbgeo.lower) !=
pgno_align2os_bytes(env, meta.mm_geo.lower) ||
bytes_align2os_bytes(env, env->me_dbgeo.shrink) !=
pgno_align2os_bytes(env, meta.mm_geo.shrink) ||
bytes_align2os_bytes(env, env->me_dbgeo.grow) !=
pgno_align2os_bytes(env, meta.mm_geo.grow)) {
if (env->me_dbgeo.shrink && env->me_dbgeo.now > used_bytes)
/* pre-shrink if enabled */
env->me_dbgeo.now = used_bytes + env->me_dbgeo.shrink -
used_bytes % env->me_dbgeo.shrink;
err = mdbx_env_set_geometry(env, env->me_dbgeo.lower, env->me_dbgeo.now,
env->me_dbgeo.upper, env->me_dbgeo.grow,
env->me_dbgeo.shrink, meta.mm_psize);
if (unlikely(err != MDBX_SUCCESS)) {
mdbx_error("could not apply preconfigured dbsize-params to db");
return MDBX_INCOMPATIBLE;
}
/* update meta fields */
meta.mm_geo.now = bytes2pgno(env, env->me_dbgeo.now);
meta.mm_geo.lower = bytes2pgno(env, env->me_dbgeo.lower);
meta.mm_geo.upper = bytes2pgno(env, env->me_dbgeo.upper);
meta.mm_geo.grow = (uint16_t)bytes2pgno(env, env->me_dbgeo.grow);
meta.mm_geo.shrink = (uint16_t)bytes2pgno(env, env->me_dbgeo.shrink);
mdbx_info("amended: root %" PRIaPGNO "/%" PRIaPGNO ", geo %" PRIaPGNO
"/%" PRIaPGNO "-%" PRIaPGNO "/%" PRIaPGNO
" +%u -%u, txn_id %" PRIaTXN ", %s",
meta.mm_dbs[MAIN_DBI].md_root, meta.mm_dbs[FREE_DBI].md_root,
meta.mm_geo.lower, meta.mm_geo.next, meta.mm_geo.now,
meta.mm_geo.upper, meta.mm_geo.grow, meta.mm_geo.shrink,
meta.mm_txnid_a, mdbx_durable_str(&meta));
}
mdbx_ensure(env, meta.mm_geo.now >= meta.mm_geo.next);
} else {
/* geo-params not pre-configured by user,
* get current values from a meta. */
env->me_dbgeo.now = pgno2bytes(env, meta.mm_geo.now);
env->me_dbgeo.lower = pgno2bytes(env, meta.mm_geo.lower);
env->me_dbgeo.upper = pgno2bytes(env, meta.mm_geo.upper);
env->me_dbgeo.grow = pgno2bytes(env, meta.mm_geo.grow);
env->me_dbgeo.shrink = pgno2bytes(env, meta.mm_geo.shrink);
}
const size_t expected_bytes =
mdbx_roundup2(pgno2bytes(env, meta.mm_geo.now), env->me_os_psize);
mdbx_ensure(env, expected_bytes >= used_bytes);
if (filesize_before_mmap != expected_bytes) {
if (lck_rc != /* lck exclusive */ MDBX_RESULT_TRUE) {
mdbx_info("filesize mismatch (expect %" PRIuPTR "/%" PRIaPGNO
", have %" PRIu64 "/%" PRIaPGNO "), "
"assume collision in non-exclusive mode",
expected_bytes, bytes2pgno(env, expected_bytes),
filesize_before_mmap,
bytes2pgno(env, (size_t)filesize_before_mmap));
} else {
mdbx_notice("filesize mismatch (expect %" PRIuSIZE "/%" PRIaPGNO
", have %" PRIu64 "/%" PRIaPGNO ")",
expected_bytes, bytes2pgno(env, expected_bytes),
filesize_before_mmap,
bytes2pgno(env, (size_t)filesize_before_mmap));
if (filesize_before_mmap < used_bytes) {
mdbx_error("last-page beyond end-of-file (last %" PRIaPGNO
", have %" PRIaPGNO ")",
meta.mm_geo.next,
bytes2pgno(env, (size_t)filesize_before_mmap));
return MDBX_CORRUPTED;
}
if (env->me_flags & MDBX_RDONLY) {
if (filesize_before_mmap % env->me_os_psize) {
mdbx_error("filesize should be rounded-up to system page");
return MDBX_WANNA_RECOVERY;
}
mdbx_notice("ignore filesize mismatch in readonly-mode");
} else {
mdbx_info("resize datafile to %" PRIuSIZE " bytes, %" PRIaPGNO " pages",
expected_bytes, bytes2pgno(env, expected_bytes));
err = mdbx_ftruncate(env->me_fd, expected_bytes);
if (unlikely(err != MDBX_SUCCESS)) {
mdbx_error("error %d, while resize datafile to %" PRIuSIZE
" bytes, %" PRIaPGNO " pages",
rc, expected_bytes, bytes2pgno(env, expected_bytes));
return err;
}
filesize_before_mmap = expected_bytes;
}
}
}
err = mdbx_env_map(env, (lck_rc != /* lck exclusive */ MDBX_RESULT_TRUE)
? 0
: expected_bytes);
if (err != MDBX_SUCCESS)
return err;
const unsigned meta_clash_mask = mdbx_meta_eq_mask(env);
if (meta_clash_mask) {
mdbx_error("meta-pages are clashed: mask 0x%d", meta_clash_mask);
return MDBX_WANNA_RECOVERY;
}
while (1) {
MDBX_meta *head = mdbx_meta_head(env);
const txnid_t head_txnid = mdbx_meta_txnid_fluid(env, head);
if (head_txnid == meta.mm_txnid_a)
break;
if (lck_rc == /* lck exclusive */ MDBX_RESULT_TRUE) {
mdbx_assert(env, META_IS_STEADY(&meta) && !META_IS_STEADY(head));
if (env->me_flags & MDBX_RDONLY) {
mdbx_error("rollback needed: (from head %" PRIaTXN
" to steady %" PRIaTXN "), but unable in read-only mode",
head_txnid, meta.mm_txnid_a);
return MDBX_WANNA_RECOVERY /* LY: could not recovery/rollback */;
}
const MDBX_meta *const meta0 = METAPAGE(env, 0);
const MDBX_meta *const meta1 = METAPAGE(env, 1);
const MDBX_meta *const meta2 = METAPAGE(env, 2);
txnid_t undo_txnid = 0;
while (
(head != meta0 && mdbx_meta_txnid_fluid(env, meta0) == undo_txnid) ||
(head != meta1 && mdbx_meta_txnid_fluid(env, meta1) == undo_txnid) ||
(head != meta2 && mdbx_meta_txnid_fluid(env, meta2) == undo_txnid))
undo_txnid += 1;
if (unlikely(undo_txnid >= meta.mm_txnid_a)) {
mdbx_fatal("rollback failed: no suitable txnid (0,1,2) < %" PRIaTXN,
meta.mm_txnid_a);
return MDBX_PANIC /* LY: could not recovery/rollback */;
}
/* LY: rollback weak checkpoint */
mdbx_trace("rollback: from %" PRIaTXN ", to %" PRIaTXN " as %" PRIaTXN,
head_txnid, meta.mm_txnid_a, undo_txnid);
mdbx_ensure(env, head_txnid == mdbx_meta_txnid_stable(env, head));
if (env->me_flags & MDBX_WRITEMAP) {
head->mm_txnid_a = undo_txnid;
head->mm_datasync_sign = MDBX_DATASIGN_WEAK;
head->mm_txnid_b = undo_txnid;
const size_t offset =
((uint8_t *)container_of(head, MDBX_page, mp_meta)) -
env->me_dxb_mmap.dxb;
const size_t paged_offset = offset & ~(env->me_os_psize - 1);
const size_t paged_length = mdbx_roundup2(
env->me_psize + offset - paged_offset, env->me_os_psize);
err = mdbx_msync(&env->me_dxb_mmap, paged_offset, paged_length, false);
} else {
MDBX_meta rollback = *head;
mdbx_meta_set_txnid(env, &rollback, undo_txnid);
rollback.mm_datasync_sign = MDBX_DATASIGN_WEAK;
err = mdbx_pwrite(env->me_fd, &rollback, sizeof(MDBX_meta),
(uint8_t *)head - (uint8_t *)env->me_map);
}
if (err)
return err;
mdbx_invalidate_cache(env->me_map, pgno2bytes(env, NUM_METAS));
mdbx_ensure(env, undo_txnid == mdbx_meta_txnid_fluid(env, head));
mdbx_ensure(env, 0 == mdbx_meta_eq_mask(env));
continue;
}
if (!env->me_lck) {
/* LY: without-lck (read-only) mode, so it is imposible that other
* process made weak checkpoint. */
mdbx_error("without-lck, unable recovery/rollback");
return MDBX_WANNA_RECOVERY;
}
/* LY: assume just have a collision with other running process,
* or someone make a weak checkpoint */
mdbx_info("assume collision or online weak checkpoint");
break;
}
const MDBX_meta *head = mdbx_meta_head(env);
if (lck_rc == /* lck exclusive */ MDBX_RESULT_TRUE) {
/* re-check file size after mmap */
uint64_t filesize_after_mmap;
err = mdbx_filesize(env->me_fd, &filesize_after_mmap);
if (unlikely(err != MDBX_SUCCESS))
return err;
if (filesize_after_mmap != expected_bytes) {
if (filesize_after_mmap != filesize_before_mmap)
mdbx_info("datafile resized by system to %" PRIu64 " bytes",
filesize_after_mmap);
if (filesize_after_mmap % env->me_os_psize ||
filesize_after_mmap > env->me_dbgeo.upper ||
filesize_after_mmap < used_bytes) {
mdbx_info("unacceptable/unexpected datafile size %" PRIu64,
filesize_after_mmap);
return MDBX_PROBLEM;
}
if ((env->me_flags & MDBX_RDONLY) == 0) {
meta.mm_geo.now =
bytes2pgno(env, env->me_dbgeo.now = (size_t)filesize_after_mmap);
mdbx_info("update meta-geo to filesize %" PRIuPTR " bytes, %" PRIaPGNO
" pages",
env->me_dbgeo.now, meta.mm_geo.now);
}
}
if (memcmp(&meta.mm_geo, &head->mm_geo, sizeof(meta.mm_geo))) {
const txnid_t txnid = mdbx_meta_txnid_stable(env, head);
mdbx_info("updating meta.geo: "
"from l%" PRIaPGNO "-n%" PRIaPGNO "-u%" PRIaPGNO
"/s%u-g%u (txn#%" PRIaTXN "), "
"to l%" PRIaPGNO "-n%" PRIaPGNO "-u%" PRIaPGNO
"/s%u-g%u (txn#%" PRIaTXN ")",
head->mm_geo.lower, head->mm_geo.now, head->mm_geo.upper,
head->mm_geo.shrink, head->mm_geo.grow, txnid,
meta.mm_geo.lower, meta.mm_geo.now, meta.mm_geo.upper,
meta.mm_geo.shrink, meta.mm_geo.grow, txnid + 1);
mdbx_ensure(env, mdbx_meta_eq(env, &meta, head));
mdbx_meta_set_txnid(env, &meta, txnid + 1);
env->me_sync_pending += env->me_psize;
err = mdbx_sync_locked(env, env->me_flags | MDBX_SHRINK_ALLOWED, &meta);
if (err) {
mdbx_info("error %d, while updating meta.geo: "
"from l%" PRIaPGNO "-n%" PRIaPGNO "-u%" PRIaPGNO
"/s%u-g%u (txn#%" PRIaTXN "), "
"to l%" PRIaPGNO "-n%" PRIaPGNO "-u%" PRIaPGNO
"/s%u-g%u (txn#%" PRIaTXN ")",
err, head->mm_geo.lower, head->mm_geo.now, head->mm_geo.upper,
head->mm_geo.shrink, head->mm_geo.grow, txnid,
meta.mm_geo.lower, meta.mm_geo.now, meta.mm_geo.upper,
meta.mm_geo.shrink, meta.mm_geo.grow, txnid + 1);
return err;
}
}
}
return rc;
}
/****************************************************************************/
/* Open and/or initialize the lock region for the environment. */
static int __cold mdbx_setup_lck(MDBX_env *env, char *lck_pathname,
mode_t mode) {
mdbx_assert(env, env->me_fd != INVALID_HANDLE_VALUE);
mdbx_assert(env, env->me_lfd == INVALID_HANDLE_VALUE);
int err = mdbx_openfile(lck_pathname, O_RDWR | O_CREAT, mode, &env->me_lfd,
(env->me_flags & MDBX_EXCLUSIVE) ? true : false);
if (err != MDBX_SUCCESS) {
if (!(err == MDBX_ENOFILE && (env->me_flags & MDBX_EXCLUSIVE)) &&
!(err == MDBX_EROFS && (env->me_flags & MDBX_RDONLY)))
return err;
/* LY: without-lck mode (e.g. exclusive or on read-only filesystem) */
env->me_lfd = INVALID_HANDLE_VALUE;
const int rc = mdbx_lck_seize(env);
if (MDBX_IS_ERROR(rc))
return rc;
env->me_oldest = &env->me_oldest_stub;
env->me_maxreaders = UINT_MAX;
#ifdef MDBX_OSAL_LOCK
env->me_wmutex = &env->me_lckless_wmutex;
#endif
mdbx_debug("lck-setup:%s%s%s", " lck-less",
(env->me_flags & MDBX_RDONLY) ? " readonly" : "",
(rc == MDBX_RESULT_TRUE) ? " exclusive" : " cooperative");
return rc;
}
/* Try to get exclusive lock. If we succeed, then
* nobody is using the lock region and we should initialize it. */
const int rc = mdbx_lck_seize(env);
if (MDBX_IS_ERROR(rc))
return rc;
mdbx_debug("lck-setup:%s%s%s", " with-lck",
(env->me_flags & MDBX_RDONLY) ? " readonly" : "",
(rc == MDBX_RESULT_TRUE) ? " exclusive" : " cooperative");
uint64_t size;
err = mdbx_filesize(env->me_lfd, &size);
if (unlikely(err != MDBX_SUCCESS))
return err;
if (rc == MDBX_RESULT_TRUE) {
uint64_t wanna = mdbx_roundup2(
(env->me_maxreaders - 1) * sizeof(MDBX_reader) + sizeof(MDBX_lockinfo),
env->me_os_psize);
#ifndef NDEBUG
err = mdbx_ftruncate(env->me_lfd, size = 0);
if (unlikely(err != MDBX_SUCCESS))
return err;
#endif
mdbx_jitter4testing(false);
if (size != wanna) {
err = mdbx_ftruncate(env->me_lfd, wanna);
if (unlikely(err != MDBX_SUCCESS))
return err;
size = wanna;
}
} else {
if (env->me_flags & MDBX_EXCLUSIVE)
return MDBX_BUSY;
if (size > SSIZE_MAX || (size & (env->me_os_psize - 1)) ||
size < env->me_os_psize) {
mdbx_notice("lck-file has invalid size %" PRIu64 " bytes", size);
return MDBX_PROBLEM;
}
}
const size_t maxreaders =
((size_t)size - sizeof(MDBX_lockinfo)) / sizeof(MDBX_reader) + 1;
if (maxreaders > UINT16_MAX) {
mdbx_error("lck-size too big (up to %" PRIuPTR " readers)", maxreaders);
return MDBX_PROBLEM;
}
env->me_maxreaders = (unsigned)maxreaders;
err = mdbx_mmap(MDBX_WRITEMAP, &env->me_lck_mmap, (size_t)size, (size_t)size);
if (unlikely(err != MDBX_SUCCESS))
return err;
#ifdef MADV_DODUMP
(void)madvise(env->me_lck, size, MADV_DODUMP);
#endif
#ifdef MADV_DONTFORK
if (madvise(env->me_lck, size, MADV_DONTFORK) < 0)
return errno;
#endif
#ifdef MADV_WILLNEED
if (madvise(env->me_lck, size, MADV_WILLNEED) < 0)
return errno;
#endif
#ifdef MADV_RANDOM
if (madvise(env->me_lck, size, MADV_RANDOM) < 0)
return errno;
#endif
if (rc == MDBX_RESULT_TRUE) {
/* LY: exlcusive mode, init lck */
memset(env->me_lck, 0, (size_t)size);
err = mdbx_lck_init(env);
if (err)
return err;
env->me_lck->mti_magic_and_version = MDBX_LOCK_MAGIC;
env->me_lck->mti_os_and_format = MDBX_LOCK_FORMAT;
} else {
if (env->me_lck->mti_magic_and_version != MDBX_LOCK_MAGIC &&
env->me_lck->mti_magic_and_version != MDBX_LOCK_MAGIC_DEVEL) {
mdbx_error("lock region has invalid magic/version");
return ((env->me_lck->mti_magic_and_version >> 8) != MDBX_MAGIC)
? MDBX_INVALID
: MDBX_VERSION_MISMATCH;
}
if (env->me_lck->mti_os_and_format != MDBX_LOCK_FORMAT) {
mdbx_error("lock region has os/format 0x%" PRIx32 ", expected 0x%" PRIx32,
env->me_lck->mti_os_and_format, MDBX_LOCK_FORMAT);
return MDBX_VERSION_MISMATCH;
}
}
mdbx_assert(env, !MDBX_IS_ERROR(rc));
env->me_oldest = &env->me_lck->mti_oldest;
#ifdef MDBX_OSAL_LOCK
env->me_wmutex = &env->me_lck->mti_wmutex;
#endif
return rc;
}
/* Only a subset of the mdbx_env flags can be changed
* at runtime. Changing other flags requires closing the
* environment and re-opening it with the new flags. */
#define CHANGEABLE \
(MDBX_NOSYNC | MDBX_NOMETASYNC | MDBX_MAPASYNC | MDBX_NOMEMINIT | \
MDBX_COALESCE | MDBX_PAGEPERTURB)
#define CHANGELESS \
(MDBX_NOSUBDIR | MDBX_RDONLY | MDBX_WRITEMAP | MDBX_NOTLS | MDBX_NORDAHEAD | \
MDBX_LIFORECLAIM | MDBX_EXCLUSIVE)
#if VALID_FLAGS & PERSISTENT_FLAGS & (CHANGEABLE | CHANGELESS)
#error "Persistent DB flags & env flags overlap, but both go in mm_flags"
#endif
int __cold mdbx_env_open(MDBX_env *env, const char *path, unsigned flags,
mode_t mode) {
if (unlikely(!env || !path))
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
if (flags & ~(CHANGEABLE | CHANGELESS))
return MDBX_EINVAL;
if (env->me_fd != INVALID_HANDLE_VALUE ||
(env->me_flags & MDBX_ENV_ACTIVE) != 0)
return MDBX_EPERM;
size_t len_full, len = strlen(path);
if (flags & MDBX_NOSUBDIR) {
len_full = len + sizeof(MDBX_LOCK_SUFFIX) + len + 1;
} else {
len_full = len + sizeof(MDBX_LOCKNAME) + len + sizeof(MDBX_DATANAME);
}
char *lck_pathname = mdbx_malloc(len_full);
if (!lck_pathname)
return MDBX_ENOMEM;
char *dxb_pathname;
if (flags & MDBX_NOSUBDIR) {
dxb_pathname = lck_pathname + len + sizeof(MDBX_LOCK_SUFFIX);
sprintf(lck_pathname, "%s" MDBX_LOCK_SUFFIX, path);
strcpy(dxb_pathname, path);
} else {
dxb_pathname = lck_pathname + len + sizeof(MDBX_LOCKNAME);
sprintf(lck_pathname, "%s" MDBX_LOCKNAME, path);
sprintf(dxb_pathname, "%s" MDBX_DATANAME, path);
}
int rc = MDBX_SUCCESS;
flags |= env->me_flags;
if (flags & MDBX_RDONLY) {
/* LY: silently ignore irrelevant flags when
* we're only getting read access */
flags &= ~(MDBX_WRITEMAP | MDBX_MAPASYNC | MDBX_NOSYNC | MDBX_NOMETASYNC |
MDBX_COALESCE | MDBX_LIFORECLAIM | MDBX_NOMEMINIT);
} else {
if (!((env->me_free_pgs = mdbx_pnl_alloc(MDBX_PNL_INITIAL)) &&
(env->me_dirtylist =
mdbx_calloc(MDBX_DPL_TXNFULL + 1, sizeof(MDBX_DP)))))
rc = MDBX_ENOMEM;
}
const uint32_t saved_me_flags = env->me_flags;
env->me_flags = (flags & ~MDBX_FATAL_ERROR) | MDBX_ENV_ACTIVE;
if (rc)
goto bailout;
env->me_path = mdbx_strdup(path);
env->me_dbxs = mdbx_calloc(env->me_maxdbs, sizeof(MDBX_dbx));
env->me_dbflags = mdbx_calloc(env->me_maxdbs, sizeof(env->me_dbflags[0]));
env->me_dbiseqs = mdbx_calloc(env->me_maxdbs, sizeof(env->me_dbiseqs[0]));
if (!(env->me_dbxs && env->me_path && env->me_dbflags && env->me_dbiseqs)) {
rc = MDBX_ENOMEM;
goto bailout;
}
env->me_dbxs[FREE_DBI].md_cmp = mdbx_cmp_int_ai; /* aligned MDBX_INTEGERKEY */
int oflags;
if (F_ISSET(flags, MDBX_RDONLY))
oflags = O_RDONLY;
else if (mode != 0)
oflags = O_RDWR | O_CREAT;
else
oflags = O_RDWR;
rc = mdbx_openfile(dxb_pathname, oflags, mode, &env->me_fd,
(env->me_flags & MDBX_EXCLUSIVE) ? true : false);
if (rc != MDBX_SUCCESS)
goto bailout;
const int lck_rc = mdbx_setup_lck(env, lck_pathname, mode);
if (MDBX_IS_ERROR(lck_rc)) {
rc = lck_rc;
goto bailout;
}
const int dxb_rc = mdbx_setup_dxb(env, lck_rc);
if (MDBX_IS_ERROR(dxb_rc)) {
rc = dxb_rc;
goto bailout;
}
mdbx_debug("opened dbenv %p", (void *)env);
if (env->me_lck) {
const unsigned mode_flags =
MDBX_WRITEMAP | MDBX_NOSYNC | MDBX_NOMETASYNC | MDBX_MAPASYNC;
if (lck_rc == MDBX_RESULT_TRUE) {
env->me_lck->mti_envmode = env->me_flags & (mode_flags | MDBX_RDONLY);
if ((env->me_flags & MDBX_EXCLUSIVE) == 0) {
/* LY: downgrade lock only if exclusive access not requested.
* in case exclusive==1, just leave value as is. */
rc = mdbx_lck_downgrade(env, true);
mdbx_debug("lck-downgrade-full: rc %i ", rc);
} else {
rc = mdbx_lck_downgrade(env, false);
mdbx_debug("lck-downgrade-partial: rc %i ", rc);
}
if (rc != MDBX_SUCCESS)
goto bailout;
} else {
if ((env->me_flags & MDBX_RDONLY) == 0) {
while (env->me_lck->mti_envmode == MDBX_RDONLY) {
if (mdbx_atomic_compare_and_swap32(&env->me_lck->mti_envmode,
MDBX_RDONLY,
env->me_flags & mode_flags))
break;
/* TODO: yield/relax cpu */
}
if ((env->me_lck->mti_envmode ^ env->me_flags) & mode_flags) {
mdbx_error("current mode/flags incompatible with requested");
rc = MDBX_INCOMPATIBLE;
goto bailout;
}
}
}
if ((env->me_flags & MDBX_NOTLS) == 0) {
rc = mdbx_rthc_alloc(&env->me_txkey, &env->me_lck->mti_readers[0],
&env->me_lck->mti_readers[env->me_maxreaders]);
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
env->me_flags |= MDBX_ENV_TXKEY;
}
}
if ((flags & MDBX_RDONLY) == 0) {
MDBX_txn *txn;
int tsize = sizeof(MDBX_txn),
size =
tsize + env->me_maxdbs * (sizeof(MDBX_db) + sizeof(MDBX_cursor *) +
sizeof(unsigned) + 1);
if ((env->me_pbuf = mdbx_calloc(2, env->me_psize)) &&
(txn = mdbx_calloc(1, size))) {
txn->mt_dbs = (MDBX_db *)((char *)txn + tsize);
txn->mt_cursors = (MDBX_cursor **)(txn->mt_dbs + env->me_maxdbs);
txn->mt_dbiseqs = (unsigned *)(txn->mt_cursors + env->me_maxdbs);
txn->mt_dbflags = (uint8_t *)(txn->mt_dbiseqs + env->me_maxdbs);
txn->mt_env = env;
txn->mt_dbxs = env->me_dbxs;
txn->mt_flags = MDBX_TXN_FINISHED;
env->me_txn0 = txn;
} else {
rc = MDBX_ENOMEM;
}
}
#if MDBX_DEBUG
if (rc == MDBX_SUCCESS) {
MDBX_meta *meta = mdbx_meta_head(env);
MDBX_db *db = &meta->mm_dbs[MAIN_DBI];
mdbx_debug("opened database version %u, pagesize %u",
(uint8_t)meta->mm_magic_and_version, env->me_psize);
mdbx_debug("using meta page %" PRIaPGNO ", txn %" PRIaTXN,
container_of(meta, MDBX_page, mp_data)->mp_pgno,
mdbx_meta_txnid_fluid(env, meta));
mdbx_debug("depth: %u", db->md_depth);
mdbx_debug("entries: %" PRIu64, db->md_entries);
mdbx_debug("branch pages: %" PRIaPGNO, db->md_branch_pages);
mdbx_debug("leaf pages: %" PRIaPGNO, db->md_leaf_pages);
mdbx_debug("overflow pages: %" PRIaPGNO, db->md_overflow_pages);
mdbx_debug("root: %" PRIaPGNO, db->md_root);
}
#endif
bailout:
if (rc) {
mdbx_env_close0(env);
env->me_flags = saved_me_flags | MDBX_FATAL_ERROR;
}
mdbx_free(lck_pathname);
return rc;
}
/* Destroy resources from mdbx_env_open(), clear our readers & DBIs */
static void __cold mdbx_env_close0(MDBX_env *env) {
if (!(env->me_flags & MDBX_ENV_ACTIVE))
return;
env->me_flags &= ~MDBX_ENV_ACTIVE;
/* Doing this here since me_dbxs may not exist during mdbx_env_close */
if (env->me_dbxs) {
for (unsigned i = env->me_maxdbs; --i >= CORE_DBS;)
mdbx_free(env->me_dbxs[i].md_name.iov_base);
mdbx_free(env->me_dbxs);
}
mdbx_free(env->me_pbuf);
mdbx_free(env->me_dbiseqs);
mdbx_free(env->me_dbflags);
mdbx_free(env->me_path);
mdbx_free(env->me_dirtylist);
if (env->me_txn0) {
mdbx_txl_free(env->me_txn0->mt_lifo_reclaimed);
mdbx_free(env->me_txn0);
}
mdbx_pnl_free(env->me_free_pgs);
if (env->me_flags & MDBX_ENV_TXKEY)
mdbx_rthc_remove(env->me_txkey);
if (env->me_live_reader)
(void)mdbx_rpid_clear(env);
if (env->me_map) {
mdbx_munmap(&env->me_dxb_mmap);
#ifdef USE_VALGRIND
VALGRIND_DISCARD(env->me_valgrind_handle);
env->me_valgrind_handle = -1;
#endif
}
if (env->me_fd != INVALID_HANDLE_VALUE) {
(void)mdbx_closefile(env->me_fd);
env->me_fd = INVALID_HANDLE_VALUE;
}
if (env->me_lck)
mdbx_munmap(&env->me_lck_mmap);
env->me_oldest = nullptr;
mdbx_lck_destroy(env);
if (env->me_lfd != INVALID_HANDLE_VALUE) {
(void)mdbx_closefile(env->me_lfd);
env->me_lfd = INVALID_HANDLE_VALUE;
}
env->me_flags = 0;
}
int __cold mdbx_env_close_ex(MDBX_env *env, int dont_sync) {
MDBX_page *dp;
int rc = MDBX_SUCCESS;
if (unlikely(!env))
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
if ((env->me_flags & (MDBX_RDONLY | MDBX_FATAL_ERROR)) == 0) {
if (env->me_txn0 && env->me_txn0->mt_owner &&
env->me_txn0->mt_owner != mdbx_thread_self())
return MDBX_BUSY;
if (!dont_sync) {
#if defined(_WIN32) || defined(_WIN64)
/* On windows, without blocking is impossible to determine whether another
* process is running a writing transaction or not.
* Because in the "owner died" condition kernel don't release
* file lock immediately. */
rc = mdbx_env_sync_ex(env, true, false);
#else
rc = mdbx_env_sync_ex(env, true, true);
rc = (rc == MDBX_BUSY || rc == EAGAIN || rc == EACCES || rc == EBUSY ||
rc == EWOULDBLOCK)
? MDBX_SUCCESS
: rc;
#endif
}
}
VALGRIND_DESTROY_MEMPOOL(env);
while ((dp = env->me_dpages) != NULL) {
ASAN_UNPOISON_MEMORY_REGION(&dp->mp_next, sizeof(dp->mp_next));
VALGRIND_MAKE_MEM_DEFINED(&dp->mp_next, sizeof(dp->mp_next));
env->me_dpages = dp->mp_next;
mdbx_free(dp);
}
mdbx_env_close0(env);
mdbx_ensure(env, mdbx_fastmutex_destroy(&env->me_dbi_lock) == MDBX_SUCCESS);
#if defined(_WIN32) || defined(_WIN64)
/* me_remap_guard don't have destructor (Slim Reader/Writer Lock) */
DeleteCriticalSection(&env->me_windowsbug_lock);
#else
mdbx_ensure(env,
mdbx_fastmutex_destroy(&env->me_lckless_wmutex) == MDBX_SUCCESS);
mdbx_ensure(env,
mdbx_fastmutex_destroy(&env->me_remap_guard) == MDBX_SUCCESS);
#endif /* Windows */
env->me_pid = 0;
env->me_signature = 0;
mdbx_free(env);
return rc;
}
__cold int mdbx_env_close(MDBX_env *env) {
return mdbx_env_close_ex(env, false);
}
/* Compare two items pointing at aligned unsigned int's. */
static int __hot mdbx_cmp_int_ai(const MDBX_val *a, const MDBX_val *b) {
mdbx_assert(NULL, a->iov_len == b->iov_len);
mdbx_assert(NULL, 0 == (uintptr_t)a->iov_base % sizeof(int) &&
0 == (uintptr_t)b->iov_base % sizeof(int));
switch (a->iov_len) {
case 4:
return mdbx_cmp2int(*(uint32_t *)a->iov_base, *(uint32_t *)b->iov_base);
case 8:
return mdbx_cmp2int(*(uint64_t *)a->iov_base, *(uint64_t *)b->iov_base);
default:
mdbx_assert_fail(NULL, "invalid size for INTEGERKEY/INTEGERDUP", mdbx_func_,
__LINE__);
return 0;
}
}
/* Compare two items pointing at 2-byte aligned unsigned int's. */
static int __hot mdbx_cmp_int_a2(const MDBX_val *a, const MDBX_val *b) {
mdbx_assert(NULL, a->iov_len == b->iov_len);
mdbx_assert(NULL, 0 == (uintptr_t)a->iov_base % sizeof(uint16_t) &&
0 == (uintptr_t)b->iov_base % sizeof(uint16_t));
#if UNALIGNED_OK
switch (a->iov_len) {
case 4:
return mdbx_cmp2int(*(uint32_t *)a->iov_base, *(uint32_t *)b->iov_base);
case 8:
return mdbx_cmp2int(*(uint64_t *)a->iov_base, *(uint64_t *)b->iov_base);
default:
mdbx_assert_fail(NULL, "invalid size for INTEGERKEY/INTEGERDUP", mdbx_func_,
__LINE__);
return 0;
}
#else
mdbx_assert(NULL, 0 == a->iov_len % sizeof(uint16_t));
{
int diff;
const uint16_t *pa, *pb, *end;
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
end = (const uint16_t *)a->iov_base;
pa = (const uint16_t *)((char *)a->iov_base + a->iov_len);
pb = (const uint16_t *)((char *)b->iov_base + a->iov_len);
do {
diff = *--pa - *--pb;
#else /* __BYTE_ORDER__ */
end = (const uint16_t *)((char *)a->iov_base + a->iov_len);
pa = (const uint16_t *)a->iov_base;
pb = (const uint16_t *)b->iov_base;
do {
diff = *pa++ - *pb++;
#endif /* __BYTE_ORDER__ */
if (likely(diff != 0))
break;
} while (pa != end);
return diff;
}
#endif /* UNALIGNED_OK */
}
/* Compare two items pointing at unsigneds of unknown alignment.
*
* This is also set as MDBX_INTEGERDUP|MDBX_DUPFIXED's MDBX_dbx.md_dcmp. */
static int __hot mdbx_cmp_int_ua(const MDBX_val *a, const MDBX_val *b) {
mdbx_assert(NULL, a->iov_len == b->iov_len);
#if UNALIGNED_OK
switch (a->iov_len) {
case 4:
return mdbx_cmp2int(*(uint32_t *)a->iov_base, *(uint32_t *)b->iov_base);
case 8:
return mdbx_cmp2int(*(uint64_t *)a->iov_base, *(uint64_t *)b->iov_base);
default:
mdbx_assert_fail(NULL, "invalid size for INTEGERKEY/INTEGERDUP", mdbx_func_,
__LINE__);
return 0;
}
#else
mdbx_assert(NULL, a->iov_len == sizeof(int) || a->iov_len == sizeof(size_t));
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
{
int diff;
const uint8_t *pa, *pb;
pa = (const uint8_t *)a->iov_base + a->iov_len;
pb = (const uint8_t *)b->iov_base + a->iov_len;
do {
diff = *--pa - *--pb;
if (likely(diff != 0))
break;
} while (pa != a->iov_base);
return diff;
}
#else /* __BYTE_ORDER__ */
return memcmp(a->iov_base, b->iov_base, a->iov_len);
#endif /* __BYTE_ORDER__ */
#endif /* UNALIGNED_OK */
}
/* Compare two items lexically */
static int __hot mdbx_cmp_memn(const MDBX_val *a, const MDBX_val *b) {
/* LY: assumes that length of keys are NOT equal for most cases,
* if no then branch-prediction should mitigate the problem */
#if 0
/* LY: without branch instructions on x86,
* but isn't best for equal length of keys */
int diff_len = mdbx_cmp2int(a->iov_len, b->iov_len);
#else
/* LY: best when length of keys are equal,
* but got a branch-penalty otherwise */
if (likely(a->iov_len == b->iov_len))
return memcmp(a->iov_base, b->iov_base, a->iov_len);
int diff_len = (a->iov_len < b->iov_len) ? -1 : 1;
#endif
size_t shortest = (a->iov_len < b->iov_len) ? a->iov_len : b->iov_len;
int diff_data = memcmp(a->iov_base, b->iov_base, shortest);
return likely(diff_data) ? diff_data : diff_len;
}
/* Compare two items in reverse byte order */
static int __hot mdbx_cmp_memnr(const MDBX_val *a, const MDBX_val *b) {
const uint8_t *pa, *pb, *end;
pa = (const uint8_t *)a->iov_base + a->iov_len;
pb = (const uint8_t *)b->iov_base + b->iov_len;
size_t minlen = (a->iov_len < b->iov_len) ? a->iov_len : b->iov_len;
end = pa - minlen;
while (pa != end) {
int diff = *--pa - *--pb;
if (likely(diff))
return diff;
}
return mdbx_cmp2int(a->iov_len, b->iov_len);
}
/* Search for key within a page, using binary search.
* Returns the smallest entry larger or equal to the key.
* If exactp is non-null, stores whether the found entry was an exact match
* in *exactp (1 or 0).
* Updates the cursor index with the index of the found entry.
* If no entry larger or equal to the key is found, returns NULL. */
static MDBX_node *__hot mdbx_node_search(MDBX_cursor *mc, MDBX_val *key,
int *exactp) {
int low, high;
int rc = 0;
MDBX_page *mp = mc->mc_pg[mc->mc_top];
MDBX_node *node = NULL;
MDBX_val nodekey;
MDBX_cmp_func *cmp;
DKBUF;
const unsigned nkeys = NUMKEYS(mp);
mdbx_debug("searching %u keys in %s %spage %" PRIaPGNO, nkeys,
IS_LEAF(mp) ? "leaf" : "branch", IS_SUBP(mp) ? "sub-" : "",
mp->mp_pgno);
low = IS_LEAF(mp) ? 0 : 1;
high = nkeys - 1;
cmp = mc->mc_dbx->md_cmp;
/* Branch pages have no data, so if using integer keys,
* alignment is guaranteed. Use faster mdbx_cmp_int_ai.
*/
if (cmp == mdbx_cmp_int_a2 && IS_BRANCH(mp))
cmp = mdbx_cmp_int_ai;
unsigned i = 0;
if (IS_LEAF2(mp)) {
nodekey.iov_len = mc->mc_db->md_xsize;
node = NODEPTR(mp, 0); /* fake */
while (low <= high) {
i = (low + high) >> 1;
nodekey.iov_base = LEAF2KEY(mp, i, nodekey.iov_len);
rc = cmp(key, &nodekey);
mdbx_debug("found leaf index %u [%s], rc = %i", i, DKEY(&nodekey), rc);
if (rc == 0)
break;
if (rc > 0)
low = i + 1;
else
high = i - 1;
}
} else {
while (low <= high) {
i = (low + high) >> 1;
node = NODEPTR(mp, i);
nodekey.iov_len = NODEKSZ(node);
nodekey.iov_base = NODEKEY(node);
rc = cmp(key, &nodekey);
if (IS_LEAF(mp))
mdbx_debug("found leaf index %u [%s], rc = %i", i, DKEY(&nodekey), rc);
else
mdbx_debug("found branch index %u [%s -> %" PRIaPGNO "], rc = %i", i,
DKEY(&nodekey), NODEPGNO(node), rc);
if (rc == 0)
break;
if (rc > 0)
low = i + 1;
else
high = i - 1;
}
}
if (rc > 0) /* Found entry is less than the key. */
i++; /* Skip to get the smallest entry larger than key. */
if (exactp)
*exactp = (rc == 0 && nkeys > 0);
/* store the key index */
mdbx_cassert(mc, i <= UINT16_MAX);
mc->mc_ki[mc->mc_top] = (indx_t)i;
if (i >= nkeys)
/* There is no entry larger or equal to the key. */
return NULL;
/* nodeptr is fake for LEAF2 */
return IS_LEAF2(mp) ? node : NODEPTR(mp, i);
}
#if 0 /* unused for now */
static void mdbx_cursor_adjust(MDBX_cursor *mc, func) {
MDBX_cursor *m2;
for (m2 = mc->mc_txn->mt_cursors[mc->mc_dbi]; m2; m2 = m2->mc_next) {
if (m2->mc_pg[m2->mc_top] == mc->mc_pg[mc->mc_top]) {
func(mc, m2);
}
}
}
#endif
/* Pop a page off the top of the cursor's stack. */
static void mdbx_cursor_pop(MDBX_cursor *mc) {
if (mc->mc_snum) {
mdbx_debug("popped page %" PRIaPGNO " off db %d cursor %p",
mc->mc_pg[mc->mc_top]->mp_pgno, DDBI(mc), (void *)mc);
mc->mc_snum--;
if (mc->mc_snum) {
mc->mc_top--;
} else {
mc->mc_flags &= ~C_INITIALIZED;
}
}
}
/* Push a page onto the top of the cursor's stack.
* Set MDBX_TXN_ERROR on failure. */
static int mdbx_cursor_push(MDBX_cursor *mc, MDBX_page *mp) {
mdbx_debug("pushing page %" PRIaPGNO " on db %d cursor %p", mp->mp_pgno,
DDBI(mc), (void *)mc);
if (unlikely(mc->mc_snum >= CURSOR_STACK)) {
mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
return MDBX_CURSOR_FULL;
}
mdbx_cassert(mc, mc->mc_snum < UINT16_MAX);
mc->mc_top = mc->mc_snum++;
mc->mc_pg[mc->mc_top] = mp;
mc->mc_ki[mc->mc_top] = 0;
return MDBX_SUCCESS;
}
/* Find the address of the page corresponding to a given page number.
* Set MDBX_TXN_ERROR on failure.
*
* [in] mc the cursor accessing the page.
* [in] pgno the page number for the page to retrieve.
* [out] ret address of a pointer where the page's address will be
* stored.
* [out] lvl dirtylist inheritance level of found page. 1=current txn,
* 0=mapped page.
*
* Returns 0 on success, non-zero on failure. */
__hot static int mdbx_page_get(MDBX_cursor *mc, pgno_t pgno, MDBX_page **ret,
int *lvl) {
MDBX_txn *txn = mc->mc_txn;
MDBX_env *env = txn->mt_env;
MDBX_page *p = NULL;
int level;
if (!(txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_WRITEMAP))) {
MDBX_txn *tx2 = txn;
level = 1;
do {
MDBX_DPL dl = tx2->mt_rw_dirtylist;
/* Spilled pages were dirtied in this txn and flushed
* because the dirty list got full. Bring this page
* back in from the map (but don't unspill it here,
* leave that unless page_touch happens again). */
if (tx2->mt_spill_pages) {
pgno_t pn = pgno << 1;
unsigned x = mdbx_pnl_search(tx2->mt_spill_pages, pn);
if (x <= MDBX_PNL_SIZE(tx2->mt_spill_pages) &&
tx2->mt_spill_pages[x] == pn)
goto mapped;
}
if (dl->length) {
unsigned y = mdbx_dpl_search(dl, pgno);
if (y <= dl->length && dl[y].pgno == pgno) {
p = dl[y].ptr;
goto done;
}
}
level++;
} while ((tx2 = tx2->mt_parent) != NULL);
}
if (unlikely(pgno >= txn->mt_next_pgno)) {
mdbx_debug("page %" PRIaPGNO " not found", pgno);
txn->mt_flags |= MDBX_TXN_ERROR;
return MDBX_PAGE_NOTFOUND;
}
level = 0;
mapped:
p = pgno2page(env, pgno);
done:
if (unlikely(p->mp_pgno != pgno)) {
mdbx_error("mismatch pgno %" PRIaPGNO " (actual) != %" PRIaPGNO
" (expected)",
p->mp_pgno, pgno);
return MDBX_CORRUPTED;
}
if (unlikely(p->mp_upper < p->mp_lower ||
PAGEHDRSZ + p->mp_upper > env->me_psize) &&
!IS_OVERFLOW(p)) {
mdbx_error("invalid page lower(%u)/upper(%u), pg-limit %u", p->mp_lower,
p->mp_upper, env->me_psize - PAGEHDRSZ);
return MDBX_CORRUPTED;
}
/* TODO: more checks here, including p->mp_validator */
*ret = p;
if (lvl)
*lvl = level;
return MDBX_SUCCESS;
}
/* Finish mdbx_page_search() / mdbx_page_search_lowest().
* The cursor is at the root page, set up the rest of it. */
__hot static int mdbx_page_search_root(MDBX_cursor *mc, MDBX_val *key,
int flags) {
MDBX_page *mp = mc->mc_pg[mc->mc_top];
int rc;
DKBUF;
while (IS_BRANCH(mp)) {
MDBX_node *node;
indx_t i;
mdbx_debug("branch page %" PRIaPGNO " has %u keys", mp->mp_pgno,
NUMKEYS(mp));
/* Don't assert on branch pages in the FreeDB. We can get here
* while in the process of rebalancing a FreeDB branch page; we must
* let that proceed. ITS#8336 */
mdbx_cassert(mc, !mc->mc_dbi || NUMKEYS(mp) > 1);
mdbx_debug("found index 0 to page %" PRIaPGNO, NODEPGNO(NODEPTR(mp, 0)));
if (flags & (MDBX_PS_FIRST | MDBX_PS_LAST)) {
i = 0;
if (flags & MDBX_PS_LAST) {
i = NUMKEYS(mp) - 1;
/* if already init'd, see if we're already in right place */
if (mc->mc_flags & C_INITIALIZED) {
if (mc->mc_ki[mc->mc_top] == i) {
mc->mc_top = mc->mc_snum++;
mp = mc->mc_pg[mc->mc_top];
goto ready;
}
}
}
} else {
int exact;
node = mdbx_node_search(mc, key, &exact);
if (node == NULL)
i = NUMKEYS(mp) - 1;
else {
i = mc->mc_ki[mc->mc_top];
if (!exact) {
mdbx_cassert(mc, i > 0);
i--;
}
}
mdbx_debug("following index %u for key [%s]", i, DKEY(key));
}
mdbx_cassert(mc, i < NUMKEYS(mp));
node = NODEPTR(mp, i);
if (unlikely((rc = mdbx_page_get(mc, NODEPGNO(node), &mp, NULL)) != 0))
return rc;
mc->mc_ki[mc->mc_top] = i;
if (unlikely(rc = mdbx_cursor_push(mc, mp)))
return rc;
ready:
if (flags & MDBX_PS_MODIFY) {
if (unlikely((rc = mdbx_page_touch(mc)) != 0))
return rc;
mp = mc->mc_pg[mc->mc_top];
}
}
if (unlikely(!IS_LEAF(mp))) {
mdbx_debug("internal error, index points to a page with 0x%02x flags!?",
mp->mp_flags);
mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
return MDBX_CORRUPTED;
}
mdbx_debug("found leaf page %" PRIaPGNO " for key [%s]", mp->mp_pgno,
DKEY(key));
mc->mc_flags |= C_INITIALIZED;
mc->mc_flags &= ~C_EOF;
return MDBX_SUCCESS;
}
/* Search for the lowest key under the current branch page.
* This just bypasses a NUMKEYS check in the current page
* before calling mdbx_page_search_root(), because the callers
* are all in situations where the current page is known to
* be underfilled. */
__hot static int mdbx_page_search_lowest(MDBX_cursor *mc) {
MDBX_page *mp = mc->mc_pg[mc->mc_top];
mdbx_cassert(mc, IS_BRANCH(mp));
MDBX_node *node = NODEPTR(mp, 0);
int rc;
if (unlikely((rc = mdbx_page_get(mc, NODEPGNO(node), &mp, NULL)) != 0))
return rc;
mc->mc_ki[mc->mc_top] = 0;
if (unlikely(rc = mdbx_cursor_push(mc, mp)))
return rc;
return mdbx_page_search_root(mc, NULL, MDBX_PS_FIRST);
}
/* Search for the page a given key should be in.
* Push it and its parent pages on the cursor stack.
*
* [in,out] mc the cursor for this operation.
* [in] key the key to search for, or NULL for first/last page.
* [in] flags If MDBX_PS_MODIFY is set, visited pages in the DB
* are touched (updated with new page numbers).
* If MDBX_PS_FIRST or MDBX_PS_LAST is set, find first or last
* leaf.
* This is used by mdbx_cursor_first() and mdbx_cursor_last().
* If MDBX_PS_ROOTONLY set, just fetch root node, no further
* lookups.
*
* Returns 0 on success, non-zero on failure. */
__hot static int mdbx_page_search(MDBX_cursor *mc, MDBX_val *key, int flags) {
int rc;
pgno_t root;
/* Make sure the txn is still viable, then find the root from
* the txn's db table and set it as the root of the cursor's stack. */
if (unlikely(mc->mc_txn->mt_flags & MDBX_TXN_BLOCKED)) {
mdbx_debug("transaction has failed, must abort");
return MDBX_BAD_TXN;
}
/* Make sure we're using an up-to-date root */
if (unlikely(*mc->mc_dbflag & DB_STALE)) {
MDBX_cursor mc2;
if (unlikely(TXN_DBI_CHANGED(mc->mc_txn, mc->mc_dbi)))
return MDBX_BAD_DBI;
rc = mdbx_cursor_init(&mc2, mc->mc_txn, MAIN_DBI);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
rc = mdbx_page_search(&mc2, &mc->mc_dbx->md_name, 0);
if (unlikely(rc != MDBX_SUCCESS))
return (rc == MDBX_NOTFOUND) ? MDBX_BAD_DBI : rc;
{
MDBX_val data;
int exact = 0;
MDBX_node *leaf = mdbx_node_search(&mc2, &mc->mc_dbx->md_name, &exact);
if (!exact)
return MDBX_BAD_DBI;
if (unlikely((leaf->mn_flags & (F_DUPDATA | F_SUBDATA)) != F_SUBDATA))
return MDBX_INCOMPATIBLE; /* not a named DB */
rc = mdbx_node_read(&mc2, leaf, &data);
if (rc)
return rc;
uint16_t md_flags;
memcpy(&md_flags, ((char *)data.iov_base + offsetof(MDBX_db, md_flags)),
sizeof(uint16_t));
/* The txn may not know this DBI, or another process may
* have dropped and recreated the DB with other flags. */
if (unlikely((mc->mc_db->md_flags & PERSISTENT_FLAGS) != md_flags))
return MDBX_INCOMPATIBLE;
memcpy(mc->mc_db, data.iov_base, sizeof(MDBX_db));
}
*mc->mc_dbflag &= ~DB_STALE;
}
root = mc->mc_db->md_root;
if (unlikely(root == P_INVALID)) { /* Tree is empty. */
mdbx_debug("tree is empty");
return MDBX_NOTFOUND;
}
mdbx_cassert(mc, root >= NUM_METAS);
if (!mc->mc_pg[0] || mc->mc_pg[0]->mp_pgno != root)
if (unlikely((rc = mdbx_page_get(mc, root, &mc->mc_pg[0], NULL)) != 0))
return rc;
mc->mc_snum = 1;
mc->mc_top = 0;
mdbx_debug("db %d root page %" PRIaPGNO " has flags 0x%X", DDBI(mc), root,
mc->mc_pg[0]->mp_flags);
if (flags & MDBX_PS_MODIFY) {
if (unlikely(rc = mdbx_page_touch(mc)))
return rc;
}
if (flags & MDBX_PS_ROOTONLY)
return MDBX_SUCCESS;
return mdbx_page_search_root(mc, key, flags);
}
static int mdbx_ovpage_free(MDBX_cursor *mc, MDBX_page *mp) {
MDBX_txn *txn = mc->mc_txn;
pgno_t pg = mp->mp_pgno;
unsigned x = 0, ovpages = mp->mp_pages;
MDBX_env *env = txn->mt_env;
MDBX_PNL sl = txn->mt_spill_pages;
pgno_t pn = pg << 1;
int rc;
mdbx_cassert(mc, (mc->mc_flags & C_GCFREEZE) == 0);
mdbx_cassert(mc, IS_OVERFLOW(mp));
mdbx_debug("free ov page %" PRIaPGNO " (%u)", pg, ovpages);
if (mdbx_audit_enabled() && env->me_reclaimed_pglist) {
mdbx_cassert(mc, mdbx_pnl_check(env->me_reclaimed_pglist, true));
const unsigned a = mdbx_pnl_search(env->me_reclaimed_pglist, pg);
mdbx_cassert(mc, a > MDBX_PNL_SIZE(env->me_reclaimed_pglist) ||
env->me_reclaimed_pglist[a] != pg);
if (a <= MDBX_PNL_SIZE(env->me_reclaimed_pglist) &&
env->me_reclaimed_pglist[a] == pg)
return MDBX_PROBLEM;
if (ovpages > 1) {
const unsigned b =
mdbx_pnl_search(env->me_reclaimed_pglist, pg + ovpages - 1);
mdbx_cassert(mc, a == b);
if (a != b)
return MDBX_PROBLEM;
}
}
/* If the page is dirty or on the spill list we just acquired it,
* so we should give it back to our current free list, if any.
* Otherwise put it onto the list of pages we freed in this txn.
*
* Won't create me_reclaimed_pglist: me_last_reclaimed must be inited along
* with it.
* Unsupported in nested txns: They would need to hide the page
* range in ancestor txns' dirty and spilled lists. */
if (env->me_reclaimed_pglist && !txn->mt_parent &&
(IS_DIRTY(mp) ||
(sl && (x = mdbx_pnl_search(sl, pn)) <= MDBX_PNL_SIZE(sl) &&
sl[x] == pn))) {
unsigned i, j;
pgno_t *mop;
MDBX_DP *dl, ix, iy;
rc = mdbx_pnl_need(&env->me_reclaimed_pglist, ovpages);
if (unlikely(rc))
return rc;
if (!IS_DIRTY(mp)) {
/* This page is no longer spilled */
if (x == MDBX_PNL_SIZE(sl))
MDBX_PNL_SIZE(sl)--;
else
sl[x] |= 1;
goto release;
}
/* Remove from dirty list */
dl = txn->mt_rw_dirtylist;
x = dl->length--;
for (ix = dl[x]; ix.ptr != mp; ix = iy) {
if (likely(x > 1)) {
x--;
iy = dl[x];
dl[x] = ix;
} else {
mdbx_cassert(mc, x > 1);
mdbx_error("not found page 0x%p #%" PRIaPGNO " in the dirtylist", mp,
mp->mp_pgno);
j = dl->length += 1;
dl[j] = ix; /* Unsorted. OK when MDBX_TXN_ERROR. */
txn->mt_flags |= MDBX_TXN_ERROR;
return MDBX_PROBLEM;
}
}
txn->mt_dirtyroom++;
if (!(env->me_flags & MDBX_WRITEMAP))
mdbx_dpage_free(env, mp, IS_OVERFLOW(mp) ? mp->mp_pages : 1);
release:
/* Insert in me_reclaimed_pglist */
mop = env->me_reclaimed_pglist;
j = MDBX_PNL_SIZE(mop) + ovpages;
for (i = MDBX_PNL_SIZE(mop); i && MDBX_PNL_DISORDERED(mop[i], pg);)
mop[j--] = mop[i--];
MDBX_PNL_SIZE(mop) += ovpages;
pgno_t n = MDBX_PNL_ASCENDING ? pg + ovpages : pg;
while (j > i)
mop[j--] = MDBX_PNL_ASCENDING ? --n : n++;
mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
} else {
rc = mdbx_pnl_append_range(&txn->mt_befree_pages, pg, ovpages);
if (unlikely(rc))
return rc;
}
mc->mc_db->md_overflow_pages -= ovpages;
if (unlikely(mc->mc_flags & C_SUB)) {
MDBX_db *outer = mdbx_outer_db(mc);
outer->md_overflow_pages -= ovpages;
}
return 0;
}
/* Return the data associated with a given node.
*
* [in] mc The cursor for this operation.
* [in] leaf The node being read.
* [out] data Updated to point to the node's data.
*
* Returns 0 on success, non-zero on failure. */
static __inline int mdbx_node_read(MDBX_cursor *mc, MDBX_node *leaf,
MDBX_val *data) {
MDBX_page *omp; /* overflow page */
pgno_t pgno;
int rc;
if (!F_ISSET(leaf->mn_flags, F_BIGDATA)) {
data->iov_len = NODEDSZ(leaf);
data->iov_base = NODEDATA(leaf);
return MDBX_SUCCESS;
}
/* Read overflow data. */
data->iov_len = NODEDSZ(leaf);
memcpy(&pgno, NODEDATA(leaf), sizeof(pgno));
if (unlikely((rc = mdbx_page_get(mc, pgno, &omp, NULL)) != 0)) {
mdbx_debug("read overflow page %" PRIaPGNO " failed", pgno);
return rc;
}
data->iov_base = PAGEDATA(omp);
return MDBX_SUCCESS;
}
int mdbx_get(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data) {
int exact = 0;
DKBUF;
mdbx_debug("===> get db %u key [%s]", dbi, DKEY(key));
if (unlikely(!key || !data || !txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
MDBX_cursor_couple cx;
int rc = mdbx_cursor_init(&cx.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
return mdbx_cursor_set(&cx.outer, key, data, MDBX_SET, &exact);
}
int mdbx_get2(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data) {
int exact = 0;
DKBUF;
mdbx_debug("===> get db %u key [%s]", dbi, DKEY(key));
if (unlikely(!key || !data || !txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
MDBX_cursor_couple cx;
int rc = mdbx_cursor_init(&cx.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
const int op =
(txn->mt_dbs[dbi].md_flags & MDBX_DUPSORT) ? MDBX_GET_BOTH : MDBX_SET_KEY;
rc = mdbx_cursor_set(&cx.outer, key, data, op, &exact);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
return exact ? MDBX_SUCCESS : MDBX_RESULT_TRUE;
}
/* Find a sibling for a page.
* Replaces the page at the top of the cursor's stack with the specified
* sibling, if one exists.
*
* [in] mc The cursor for this operation.
* [in] move_right Non-zero if the right sibling is requested,
* otherwise the left sibling.
*
* Returns 0 on success, non-zero on failure. */
static int mdbx_cursor_sibling(MDBX_cursor *mc, int move_right) {
int rc;
MDBX_node *indx;
MDBX_page *mp;
if (unlikely(mc->mc_snum < 2)) {
return MDBX_NOTFOUND; /* root has no siblings */
}
mdbx_cursor_pop(mc);
mdbx_debug("parent page is page %" PRIaPGNO ", index %u",
mc->mc_pg[mc->mc_top]->mp_pgno, mc->mc_ki[mc->mc_top]);
if (move_right
? (mc->mc_ki[mc->mc_top] + 1u >= NUMKEYS(mc->mc_pg[mc->mc_top]))
: (mc->mc_ki[mc->mc_top] == 0)) {
mdbx_debug("no more keys left, moving to %s sibling",
move_right ? "right" : "left");
if (unlikely((rc = mdbx_cursor_sibling(mc, move_right)) != MDBX_SUCCESS)) {
/* undo cursor_pop before returning */
mc->mc_top++;
mc->mc_snum++;
return rc;
}
} else {
if (move_right)
mc->mc_ki[mc->mc_top]++;
else
mc->mc_ki[mc->mc_top]--;
mdbx_debug("just moving to %s index key %u", move_right ? "right" : "left",
mc->mc_ki[mc->mc_top]);
}
mdbx_cassert(mc, IS_BRANCH(mc->mc_pg[mc->mc_top]));
indx = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
if (unlikely((rc = mdbx_page_get(mc, NODEPGNO(indx), &mp, NULL)) != 0)) {
/* mc will be inconsistent if caller does mc_snum++ as above */
mc->mc_flags &= ~(C_INITIALIZED | C_EOF);
return rc;
}
rc = mdbx_cursor_push(mc, mp);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
if (!move_right)
mc->mc_ki[mc->mc_top] = NUMKEYS(mp) - 1;
return MDBX_SUCCESS;
}
/* Move the cursor to the next data item. */
static int mdbx_cursor_next(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
MDBX_cursor_op op) {
MDBX_page *mp;
MDBX_node *leaf;
int rc;
if ((mc->mc_flags & C_DEL) && op == MDBX_NEXT_DUP)
return MDBX_NOTFOUND;
if (!(mc->mc_flags & C_INITIALIZED))
return mdbx_cursor_first(mc, key, data);
mp = mc->mc_pg[mc->mc_top];
if (mc->mc_flags & C_EOF) {
if (mc->mc_ki[mc->mc_top] + 1u >= NUMKEYS(mp))
return MDBX_NOTFOUND;
mc->mc_flags ^= C_EOF;
}
if (mc->mc_db->md_flags & MDBX_DUPSORT) {
leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
if (op == MDBX_NEXT || op == MDBX_NEXT_DUP) {
rc =
mdbx_cursor_next(&mc->mc_xcursor->mx_cursor, data, NULL, MDBX_NEXT);
if (op != MDBX_NEXT || rc != MDBX_NOTFOUND) {
if (likely(rc == MDBX_SUCCESS))
MDBX_GET_KEY(leaf, key);
return rc;
}
}
} else {
mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
if (op == MDBX_NEXT_DUP)
return MDBX_NOTFOUND;
}
}
mdbx_debug("cursor_next: top page is %" PRIaPGNO " in cursor %p", mp->mp_pgno,
(void *)mc);
if (mc->mc_flags & C_DEL) {
mc->mc_flags ^= C_DEL;
goto skip;
}
if (mc->mc_ki[mc->mc_top] + 1u >= NUMKEYS(mp)) {
mdbx_debug("=====> move to next sibling page");
if (unlikely((rc = mdbx_cursor_sibling(mc, 1)) != MDBX_SUCCESS)) {
mc->mc_flags |= C_EOF;
return rc;
}
mp = mc->mc_pg[mc->mc_top];
mdbx_debug("next page is %" PRIaPGNO ", key index %u", mp->mp_pgno,
mc->mc_ki[mc->mc_top]);
} else
mc->mc_ki[mc->mc_top]++;
skip:
mdbx_debug("==> cursor points to page %" PRIaPGNO
" with %u keys, key index %u",
mp->mp_pgno, NUMKEYS(mp), mc->mc_ki[mc->mc_top]);
if (IS_LEAF2(mp)) {
key->iov_len = mc->mc_db->md_xsize;
key->iov_base = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], key->iov_len);
return MDBX_SUCCESS;
}
mdbx_cassert(mc, IS_LEAF(mp));
leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
rc = mdbx_xcursor_init1(mc, leaf);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
if (data) {
if (unlikely((rc = mdbx_node_read(mc, leaf, data)) != MDBX_SUCCESS))
return rc;
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
rc = mdbx_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
}
MDBX_GET_KEY(leaf, key);
return MDBX_SUCCESS;
}
/* Move the cursor to the previous data item. */
static int mdbx_cursor_prev(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
MDBX_cursor_op op) {
MDBX_page *mp;
MDBX_node *leaf;
int rc;
if ((mc->mc_flags & C_DEL) && op == MDBX_PREV_DUP)
return MDBX_NOTFOUND;
if (!(mc->mc_flags & C_INITIALIZED)) {
rc = mdbx_cursor_last(mc, key, data);
if (unlikely(rc))
return rc;
mc->mc_ki[mc->mc_top]++;
}
mp = mc->mc_pg[mc->mc_top];
if ((mc->mc_db->md_flags & MDBX_DUPSORT) &&
mc->mc_ki[mc->mc_top] < NUMKEYS(mp)) {
leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
if (op == MDBX_PREV || op == MDBX_PREV_DUP) {
rc =
mdbx_cursor_prev(&mc->mc_xcursor->mx_cursor, data, NULL, MDBX_PREV);
if (op != MDBX_PREV || rc != MDBX_NOTFOUND) {
if (likely(rc == MDBX_SUCCESS)) {
MDBX_GET_KEY(leaf, key);
mc->mc_flags &= ~C_EOF;
}
return rc;
}
}
} else {
mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
if (op == MDBX_PREV_DUP)
return MDBX_NOTFOUND;
}
}
mdbx_debug("cursor_prev: top page is %" PRIaPGNO " in cursor %p", mp->mp_pgno,
(void *)mc);
mc->mc_flags &= ~(C_EOF | C_DEL);
if (mc->mc_ki[mc->mc_top] == 0) {
mdbx_debug("=====> move to prev sibling page");
if ((rc = mdbx_cursor_sibling(mc, 0)) != MDBX_SUCCESS) {
return rc;
}
mp = mc->mc_pg[mc->mc_top];
mc->mc_ki[mc->mc_top] = NUMKEYS(mp) - 1;
mdbx_debug("prev page is %" PRIaPGNO ", key index %u", mp->mp_pgno,
mc->mc_ki[mc->mc_top]);
} else
mc->mc_ki[mc->mc_top]--;
mdbx_debug("==> cursor points to page %" PRIaPGNO
" with %u keys, key index %u",
mp->mp_pgno, NUMKEYS(mp), mc->mc_ki[mc->mc_top]);
if (IS_LEAF2(mp)) {
key->iov_len = mc->mc_db->md_xsize;
key->iov_base = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], key->iov_len);
return MDBX_SUCCESS;
}
mdbx_cassert(mc, IS_LEAF(mp));
leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
rc = mdbx_xcursor_init1(mc, leaf);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
if (data) {
if (unlikely((rc = mdbx_node_read(mc, leaf, data)) != MDBX_SUCCESS))
return rc;
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
rc = mdbx_cursor_last(&mc->mc_xcursor->mx_cursor, data, NULL);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
}
MDBX_GET_KEY(leaf, key);
return MDBX_SUCCESS;
}
/* Set the cursor on a specific data item. */
__hot static int mdbx_cursor_set(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
MDBX_cursor_op op, int *exactp) {
int rc;
MDBX_page *mp;
MDBX_node *leaf = NULL;
DKBUF;
if ((mc->mc_db->md_flags & MDBX_INTEGERKEY) &&
unlikely(key->iov_len != sizeof(uint32_t) &&
key->iov_len != sizeof(uint64_t))) {
mdbx_cassert(mc, !"key-size is invalid for MDBX_INTEGERKEY");
return MDBX_BAD_VALSIZE;
}
if (mc->mc_xcursor)
mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
/* See if we're already on the right page */
if (mc->mc_flags & C_INITIALIZED) {
MDBX_val nodekey;
mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]));
mp = mc->mc_pg[mc->mc_top];
if (!NUMKEYS(mp)) {
mc->mc_ki[mc->mc_top] = 0;
return MDBX_NOTFOUND;
}
if (IS_LEAF2(mp)) {
nodekey.iov_len = mc->mc_db->md_xsize;
nodekey.iov_base = LEAF2KEY(mp, 0, nodekey.iov_len);
} else {
leaf = NODEPTR(mp, 0);
MDBX_GET_KEY2(leaf, nodekey);
}
rc = mc->mc_dbx->md_cmp(key, &nodekey);
if (unlikely(rc == 0)) {
/* Probably happens rarely, but first node on the page
* was the one we wanted. */
mc->mc_ki[mc->mc_top] = 0;
if (exactp)
*exactp = 1;
goto set1;
}
if (rc > 0) {
const unsigned nkeys = NUMKEYS(mp);
unsigned i;
if (nkeys > 1) {
if (IS_LEAF2(mp)) {
nodekey.iov_base = LEAF2KEY(mp, nkeys - 1, nodekey.iov_len);
} else {
leaf = NODEPTR(mp, nkeys - 1);
MDBX_GET_KEY2(leaf, nodekey);
}
rc = mc->mc_dbx->md_cmp(key, &nodekey);
if (rc == 0) {
/* last node was the one we wanted */
mdbx_cassert(mc, nkeys >= 1 && nkeys <= UINT16_MAX + 1);
mc->mc_ki[mc->mc_top] = (indx_t)(nkeys - 1);
if (exactp)
*exactp = 1;
goto set1;
}
if (rc < 0) {
if (mc->mc_ki[mc->mc_top] < NUMKEYS(mp)) {
/* This is definitely the right page, skip search_page */
if (IS_LEAF2(mp)) {
nodekey.iov_base =
LEAF2KEY(mp, mc->mc_ki[mc->mc_top], nodekey.iov_len);
} else {
leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
MDBX_GET_KEY2(leaf, nodekey);
}
rc = mc->mc_dbx->md_cmp(key, &nodekey);
if (rc == 0) {
/* current node was the one we wanted */
if (exactp)
*exactp = 1;
goto set1;
}
}
rc = 0;
mc->mc_flags &= ~C_EOF;
goto set2;
}
}
/* If any parents have right-sibs, search.
* Otherwise, there's nothing further. */
for (i = 0; i < mc->mc_top; i++)
if (mc->mc_ki[i] < NUMKEYS(mc->mc_pg[i]) - 1)
break;
if (i == mc->mc_top) {
/* There are no other pages */
mdbx_cassert(mc, nkeys <= UINT16_MAX);
mc->mc_ki[mc->mc_top] = (uint16_t)nkeys;
return MDBX_NOTFOUND;
}
}
if (!mc->mc_top) {
/* There are no other pages */
mc->mc_ki[mc->mc_top] = 0;
if (op == MDBX_SET_RANGE && !exactp) {
rc = 0;
goto set1;
} else
return MDBX_NOTFOUND;
}
} else {
mc->mc_pg[0] = 0;
}
rc = mdbx_page_search(mc, key, 0);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
mp = mc->mc_pg[mc->mc_top];
mdbx_cassert(mc, IS_LEAF(mp));
set2:
leaf = mdbx_node_search(mc, key, exactp);
if (exactp != NULL && !*exactp) {
/* MDBX_SET specified and not an exact match. */
return MDBX_NOTFOUND;
}
if (leaf == NULL) {
mdbx_debug("===> inexact leaf not found, goto sibling");
if (unlikely((rc = mdbx_cursor_sibling(mc, 1)) != MDBX_SUCCESS)) {
mc->mc_flags |= C_EOF;
return rc; /* no entries matched */
}
mp = mc->mc_pg[mc->mc_top];
mdbx_cassert(mc, IS_LEAF(mp));
leaf = NODEPTR(mp, 0);
}
set1:
mc->mc_flags |= C_INITIALIZED;
mc->mc_flags &= ~C_EOF;
if (IS_LEAF2(mp)) {
if (op == MDBX_SET_RANGE || op == MDBX_SET_KEY) {
key->iov_len = mc->mc_db->md_xsize;
key->iov_base = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], key->iov_len);
}
return MDBX_SUCCESS;
}
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
rc = mdbx_xcursor_init1(mc, leaf);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
if (likely(data)) {
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
if (op == MDBX_SET || op == MDBX_SET_KEY || op == MDBX_SET_RANGE) {
rc = mdbx_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
} else {
int ex2, *ex2p;
if (op == MDBX_GET_BOTH) {
ex2p = &ex2;
ex2 = 0;
} else {
ex2p = NULL;
}
rc = mdbx_cursor_set(&mc->mc_xcursor->mx_cursor, data, NULL,
MDBX_SET_RANGE, ex2p);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
} else if (op == MDBX_GET_BOTH || op == MDBX_GET_BOTH_RANGE) {
MDBX_val olddata;
if (unlikely((rc = mdbx_node_read(mc, leaf, &olddata)) != MDBX_SUCCESS))
return rc;
if (unlikely(mc->mc_dbx->md_dcmp == NULL))
return MDBX_EINVAL;
rc = mc->mc_dbx->md_dcmp(data, &olddata);
if (rc) {
if (op != MDBX_GET_BOTH_RANGE || rc > 0)
return MDBX_NOTFOUND;
rc = 0;
}
*data = olddata;
} else {
if (mc->mc_xcursor)
mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
if (unlikely((rc = mdbx_node_read(mc, leaf, data)) != MDBX_SUCCESS))
return rc;
}
}
/* The key already matches in all other cases */
if (op == MDBX_SET_RANGE || op == MDBX_SET_KEY)
MDBX_GET_KEY(leaf, key);
mdbx_debug("==> cursor placed on key [%s], data [%s]", DKEY(key), DVAL(data));
return rc;
}
/* Move the cursor to the first item in the database. */
static int mdbx_cursor_first(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data) {
int rc;
MDBX_node *leaf;
if (mc->mc_xcursor)
mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
if (!(mc->mc_flags & C_INITIALIZED) || mc->mc_top) {
rc = mdbx_page_search(mc, NULL, MDBX_PS_FIRST);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]));
leaf = NODEPTR(mc->mc_pg[mc->mc_top], 0);
mc->mc_flags |= C_INITIALIZED;
mc->mc_flags &= ~C_EOF;
mc->mc_ki[mc->mc_top] = 0;
if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
key->iov_len = mc->mc_db->md_xsize;
key->iov_base = LEAF2KEY(mc->mc_pg[mc->mc_top], 0, key->iov_len);
return MDBX_SUCCESS;
}
if (likely(data)) {
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
rc = mdbx_xcursor_init1(mc, leaf);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
rc = mdbx_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
if (unlikely(rc))
return rc;
} else {
if (unlikely((rc = mdbx_node_read(mc, leaf, data)) != MDBX_SUCCESS))
return rc;
}
}
MDBX_GET_KEY(leaf, key);
return MDBX_SUCCESS;
}
/* Move the cursor to the last item in the database. */
static int mdbx_cursor_last(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data) {
int rc;
MDBX_node *leaf;
if (mc->mc_xcursor)
mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
if (likely((mc->mc_flags & (C_EOF | C_DEL)) != C_EOF)) {
if (!(mc->mc_flags & C_INITIALIZED) || mc->mc_top) {
rc = mdbx_page_search(mc, NULL, MDBX_PS_LAST);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]));
}
mc->mc_ki[mc->mc_top] = NUMKEYS(mc->mc_pg[mc->mc_top]) - 1;
mc->mc_flags |= C_INITIALIZED | C_EOF;
leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
key->iov_len = mc->mc_db->md_xsize;
key->iov_base =
LEAF2KEY(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], key->iov_len);
return MDBX_SUCCESS;
}
if (likely(data)) {
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
rc = mdbx_xcursor_init1(mc, leaf);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
rc = mdbx_cursor_last(&mc->mc_xcursor->mx_cursor, data, NULL);
if (unlikely(rc))
return rc;
} else {
if (unlikely((rc = mdbx_node_read(mc, leaf, data)) != MDBX_SUCCESS))
return rc;
}
}
MDBX_GET_KEY(leaf, key);
return MDBX_SUCCESS;
}
int mdbx_cursor_get(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
MDBX_cursor_op op) {
int rc;
int exact = 0;
int (*mfunc)(MDBX_cursor * mc, MDBX_val * key, MDBX_val * data);
if (unlikely(mc == NULL))
return MDBX_EINVAL;
if (unlikely(mc->mc_signature != MDBX_MC_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(mc->mc_txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
switch (op) {
case MDBX_GET_CURRENT: {
if (unlikely(!(mc->mc_flags & C_INITIALIZED)))
return MDBX_EINVAL;
MDBX_page *mp = mc->mc_pg[mc->mc_top];
const unsigned nkeys = NUMKEYS(mp);
if (mc->mc_ki[mc->mc_top] >= nkeys) {
mdbx_cassert(mc, nkeys <= UINT16_MAX);
mc->mc_ki[mc->mc_top] = (uint16_t)nkeys;
return MDBX_NOTFOUND;
}
mdbx_cassert(mc, nkeys > 0);
rc = MDBX_SUCCESS;
if (IS_LEAF2(mp)) {
key->iov_len = mc->mc_db->md_xsize;
key->iov_base = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], key->iov_len);
} else {
MDBX_node *leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
MDBX_GET_KEY(leaf, key);
if (data) {
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
if (unlikely(!(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED))) {
rc = mdbx_xcursor_init1(mc, leaf);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
rc = mdbx_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
if (unlikely(rc))
return rc;
}
rc = mdbx_cursor_get(&mc->mc_xcursor->mx_cursor, data, NULL,
MDBX_GET_CURRENT);
} else {
rc = mdbx_node_read(mc, leaf, data);
}
if (unlikely(rc))
return rc;
}
}
break;
}
case MDBX_GET_BOTH:
case MDBX_GET_BOTH_RANGE:
if (unlikely(data == NULL))
return MDBX_EINVAL;
if (unlikely(mc->mc_xcursor == NULL))
return MDBX_INCOMPATIBLE;
/* FALLTHRU */
case MDBX_SET:
case MDBX_SET_KEY:
case MDBX_SET_RANGE:
if (unlikely(key == NULL))
return MDBX_EINVAL;
rc = mdbx_cursor_set(mc, key, data, op,
op == MDBX_SET_RANGE ? NULL : &exact);
break;
case MDBX_GET_MULTIPLE:
if (unlikely(data == NULL || !(mc->mc_flags & C_INITIALIZED)))
return MDBX_EINVAL;
if (unlikely(!(mc->mc_db->md_flags & MDBX_DUPFIXED)))
return MDBX_INCOMPATIBLE;
rc = MDBX_SUCCESS;
if (!(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) ||
(mc->mc_xcursor->mx_cursor.mc_flags & C_EOF))
break;
goto fetchm;
case MDBX_NEXT_MULTIPLE:
if (unlikely(data == NULL))
return MDBX_EINVAL;
if (unlikely(!(mc->mc_db->md_flags & MDBX_DUPFIXED)))
return MDBX_INCOMPATIBLE;
rc = mdbx_cursor_next(mc, key, data, MDBX_NEXT_DUP);
if (rc == MDBX_SUCCESS) {
if (mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) {
MDBX_cursor *mx;
fetchm:
mx = &mc->mc_xcursor->mx_cursor;
data->iov_len = NUMKEYS(mx->mc_pg[mx->mc_top]) * mx->mc_db->md_xsize;
data->iov_base = PAGEDATA(mx->mc_pg[mx->mc_top]);
mx->mc_ki[mx->mc_top] = NUMKEYS(mx->mc_pg[mx->mc_top]) - 1;
} else {
rc = MDBX_NOTFOUND;
}
}
break;
case MDBX_PREV_MULTIPLE:
if (data == NULL)
return MDBX_EINVAL;
if (!(mc->mc_db->md_flags & MDBX_DUPFIXED))
return MDBX_INCOMPATIBLE;
rc = MDBX_SUCCESS;
if (!(mc->mc_flags & C_INITIALIZED))
rc = mdbx_cursor_last(mc, key, data);
if (rc == MDBX_SUCCESS) {
MDBX_cursor *mx = &mc->mc_xcursor->mx_cursor;
if (mx->mc_flags & C_INITIALIZED) {
rc = mdbx_cursor_sibling(mx, 0);
if (rc == MDBX_SUCCESS)
goto fetchm;
} else {
rc = MDBX_NOTFOUND;
}
}
break;
case MDBX_NEXT:
case MDBX_NEXT_DUP:
case MDBX_NEXT_NODUP:
rc = mdbx_cursor_next(mc, key, data, op);
break;
case MDBX_PREV:
case MDBX_PREV_DUP:
case MDBX_PREV_NODUP:
rc = mdbx_cursor_prev(mc, key, data, op);
break;
case MDBX_FIRST:
rc = mdbx_cursor_first(mc, key, data);
break;
case MDBX_FIRST_DUP:
mfunc = mdbx_cursor_first;
mmove:
if (unlikely(data == NULL || !(mc->mc_flags & C_INITIALIZED)))
return MDBX_EINVAL;
if (unlikely(mc->mc_xcursor == NULL))
return MDBX_INCOMPATIBLE;
if (mc->mc_ki[mc->mc_top] >= NUMKEYS(mc->mc_pg[mc->mc_top])) {
mc->mc_ki[mc->mc_top] = NUMKEYS(mc->mc_pg[mc->mc_top]);
return MDBX_NOTFOUND;
}
{
MDBX_node *leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
if (!F_ISSET(leaf->mn_flags, F_DUPDATA)) {
MDBX_GET_KEY(leaf, key);
rc = mdbx_node_read(mc, leaf, data);
break;
}
}
if (unlikely(!(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED)))
return MDBX_EINVAL;
rc = mfunc(&mc->mc_xcursor->mx_cursor, data, NULL);
break;
case MDBX_LAST:
rc = mdbx_cursor_last(mc, key, data);
break;
case MDBX_LAST_DUP:
mfunc = mdbx_cursor_last;
goto mmove;
default:
mdbx_debug("unhandled/unimplemented cursor operation %u", op);
return MDBX_EINVAL;
}
mc->mc_flags &= ~C_DEL;
return rc;
}
/* Touch all the pages in the cursor stack. Set mc_top.
* Makes sure all the pages are writable, before attempting a write operation.
* [in] mc The cursor to operate on. */
static int mdbx_cursor_touch(MDBX_cursor *mc) {
int rc = MDBX_SUCCESS;
if (mc->mc_dbi >= CORE_DBS &&
(*mc->mc_dbflag & (DB_DIRTY | DB_DUPDATA)) == 0) {
mdbx_cassert(mc, (mc->mc_flags & C_RECLAIMING) == 0);
/* Touch DB record of named DB */
MDBX_cursor_couple cx;
if (TXN_DBI_CHANGED(mc->mc_txn, mc->mc_dbi))
return MDBX_BAD_DBI;
rc = mdbx_cursor_init(&cx.outer, mc->mc_txn, MAIN_DBI);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
rc = mdbx_page_search(&cx.outer, &mc->mc_dbx->md_name, MDBX_PS_MODIFY);
if (unlikely(rc))
return rc;
*mc->mc_dbflag |= DB_DIRTY;
}
mc->mc_top = 0;
if (mc->mc_snum) {
do {
rc = mdbx_page_touch(mc);
} while (!rc && ++(mc->mc_top) < mc->mc_snum);
mc->mc_top = mc->mc_snum - 1;
}
return rc;
}
int mdbx_cursor_put(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
unsigned flags) {
MDBX_env *env;
MDBX_page *fp, *sub_root = NULL;
uint16_t fp_flags;
MDBX_val xdata, *rdata, dkey, olddata;
MDBX_db dummy;
unsigned mcount = 0, dcount = 0, nospill;
size_t nsize;
int rc = MDBX_SUCCESS, rc2;
unsigned nflags;
DKBUF;
if (unlikely(mc == NULL || key == NULL))
return MDBX_EINVAL;
if (unlikely(mc->mc_signature != MDBX_MC_SIGNATURE))
return MDBX_EBADSIGN;
env = mc->mc_txn->mt_env;
/* Check this first so counter will always be zero on any early failures. */
if (flags & MDBX_MULTIPLE) {
if (unlikely(!F_ISSET(mc->mc_db->md_flags, MDBX_DUPFIXED)))
return MDBX_INCOMPATIBLE;
if (unlikely(data[1].iov_len >= INT_MAX))
return MDBX_EINVAL;
dcount = (unsigned)data[1].iov_len;
data[1].iov_len = 0;
}
if (flags & MDBX_RESERVE) {
if (unlikely(mc->mc_db->md_flags & (MDBX_DUPSORT | MDBX_REVERSEDUP)))
return MDBX_INCOMPATIBLE;
data->iov_base = nullptr;
}
nospill = flags & MDBX_NOSPILL;
flags &= ~MDBX_NOSPILL;
if (unlikely(mc->mc_txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_BLOCKED)))
return (mc->mc_txn->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EACCESS
: MDBX_BAD_TXN;
if (unlikely(key->iov_len > env->me_maxkey_limit))
return MDBX_BAD_VALSIZE;
if (unlikely(data->iov_len > ((mc->mc_db->md_flags & MDBX_DUPSORT)
? env->me_maxkey_limit
: MDBX_MAXDATASIZE)))
return MDBX_BAD_VALSIZE;
if ((mc->mc_db->md_flags & MDBX_INTEGERKEY) &&
unlikely(key->iov_len != sizeof(uint32_t) &&
key->iov_len != sizeof(uint64_t))) {
mdbx_cassert(mc, !"key-size is invalid for MDBX_INTEGERKEY");
return MDBX_BAD_VALSIZE;
}
if ((mc->mc_db->md_flags & MDBX_INTEGERDUP) &&
unlikely(data->iov_len != sizeof(uint32_t) &&
data->iov_len != sizeof(uint64_t))) {
mdbx_cassert(mc, !"data-size is invalid MDBX_INTEGERDUP");
return MDBX_BAD_VALSIZE;
}
mdbx_debug("==> put db %d key [%s], size %" PRIuPTR
", data [%s] size %" PRIuPTR,
DDBI(mc), DKEY(key), key ? key->iov_len : 0,
DVAL((flags & MDBX_RESERVE) ? nullptr : data), data->iov_len);
int dupdata_flag = 0;
if ((flags & MDBX_CURRENT) != 0 && (mc->mc_flags & C_SUB) == 0) {
/* Опция MDBX_CURRENT означает, что запрошено обновление текущей записи,
* на которой сейчас стоит курсор. Проверяем что переданный ключ совпадает
* со значением в текущей позиции курсора.
* Здесь проще вызвать mdbx_cursor_get(), так как для обслуживания таблиц
* с MDBX_DUPSORT также требуется текущий размер данных. */
MDBX_val current_key, current_data;
rc = mdbx_cursor_get(mc, ¤t_key, ¤t_data, MDBX_GET_CURRENT);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
if (mc->mc_dbx->md_cmp(key, ¤t_key) != 0)
return MDBX_EKEYMISMATCH;
if (F_ISSET(mc->mc_db->md_flags, MDBX_DUPSORT)) {
MDBX_node *leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
mdbx_cassert(mc,
mc->mc_xcursor != NULL &&
(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED));
/* Если за ключом более одного значения, либо если размер данных
* отличается, то вместо inplace обновления требуется удаление и
* последующая вставка. */
if (mc->mc_xcursor->mx_db.md_entries > 1 ||
current_data.iov_len != data->iov_len) {
rc = mdbx_cursor_del(mc, 0);
if (rc != MDBX_SUCCESS)
return rc;
flags -= MDBX_CURRENT;
}
}
}
}
if (mc->mc_db->md_root == P_INVALID) {
/* new database, cursor has nothing to point to */
mc->mc_snum = 0;
mc->mc_top = 0;
mc->mc_flags &= ~C_INITIALIZED;
rc = MDBX_NO_ROOT;
} else if ((flags & MDBX_CURRENT) == 0) {
int exact = 0;
MDBX_val d2;
if (flags & MDBX_APPEND) {
MDBX_val k2;
rc = mdbx_cursor_last(mc, &k2, &d2);
if (rc == 0) {
rc = mc->mc_dbx->md_cmp(key, &k2);
if (rc > 0) {
rc = MDBX_NOTFOUND;
mc->mc_ki[mc->mc_top]++;
} else if (unlikely(rc < 0 || (flags & MDBX_APPENDDUP) == 0)) {
/* new key is <= last key */
rc = MDBX_EKEYMISMATCH;
}
}
} else {
rc = mdbx_cursor_set(mc, key, &d2, MDBX_SET, &exact);
}
if ((flags & MDBX_NOOVERWRITE) &&
(rc == MDBX_SUCCESS || rc == MDBX_EKEYMISMATCH)) {
mdbx_debug("duplicate key [%s]", DKEY(key));
*data = d2;
return MDBX_KEYEXIST;
}
if (rc && unlikely(rc != MDBX_NOTFOUND))
return rc;
}
mc->mc_flags &= ~C_DEL;
/* Cursor is positioned, check for room in the dirty list */
if (!nospill) {
if (flags & MDBX_MULTIPLE) {
rdata = &xdata;
xdata.iov_len = data->iov_len * dcount;
} else {
rdata = data;
}
if (unlikely(rc2 = mdbx_page_spill(mc, key, rdata)))
return rc2;
}
if (rc == MDBX_NO_ROOT) {
MDBX_page *np;
/* new database, write a root leaf page */
mdbx_debug("allocating new root leaf page");
if (unlikely(rc2 = mdbx_page_new(mc, P_LEAF, 1, &np))) {
return rc2;
}
rc2 = mdbx_cursor_push(mc, np);
if (unlikely(rc2 != MDBX_SUCCESS))
return rc2;
mc->mc_db->md_root = np->mp_pgno;
mc->mc_db->md_depth++;
*mc->mc_dbflag |= DB_DIRTY;
if ((mc->mc_db->md_flags & (MDBX_DUPSORT | MDBX_DUPFIXED)) == MDBX_DUPFIXED)
np->mp_flags |= P_LEAF2;
mc->mc_flags |= C_INITIALIZED;
} else {
/* make sure all cursor pages are writable */
rc2 = mdbx_cursor_touch(mc);
if (unlikely(rc2))
return rc2;
}
bool insert_key, insert_data, do_sub = false;
insert_key = insert_data = (rc != MDBX_SUCCESS);
if (insert_key) {
/* The key does not exist */
mdbx_debug("inserting key at index %i", mc->mc_ki[mc->mc_top]);
if ((mc->mc_db->md_flags & MDBX_DUPSORT) &&
LEAFSIZE(key, data) > env->me_nodemax) {
/* Too big for a node, insert in sub-DB. Set up an empty
* "old sub-page" for prep_subDB to expand to a full page. */
fp_flags = P_LEAF | P_DIRTY;
fp = env->me_pbuf;
fp->mp_leaf2_ksize = (uint16_t)data->iov_len; /* used if MDBX_DUPFIXED */
fp->mp_lower = fp->mp_upper = 0;
olddata.iov_len = PAGEHDRSZ;
goto prep_subDB;
}
} else {
/* there's only a key anyway, so this is a no-op */
if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
char *ptr;
unsigned ksize = mc->mc_db->md_xsize;
if (key->iov_len != ksize)
return MDBX_BAD_VALSIZE;
ptr = LEAF2KEY(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], ksize);
memcpy(ptr, key->iov_base, ksize);
fix_parent:
/* if overwriting slot 0 of leaf, need to
* update branch key if there is a parent page */
if (mc->mc_top && !mc->mc_ki[mc->mc_top]) {
unsigned dtop = 1;
mc->mc_top--;
/* slot 0 is always an empty key, find real slot */
while (mc->mc_top && !mc->mc_ki[mc->mc_top]) {
mc->mc_top--;
dtop++;
}
if (mc->mc_ki[mc->mc_top])
rc2 = mdbx_update_key(mc, key);
else
rc2 = MDBX_SUCCESS;
mdbx_cassert(mc, mc->mc_top + dtop < UINT16_MAX);
mc->mc_top += (uint16_t)dtop;
if (rc2)
return rc2;
}
if (mdbx_audit_enabled()) {
int err = mdbx_cursor_check(mc, false);
if (unlikely(err != MDBX_SUCCESS))
return err;
}
return MDBX_SUCCESS;
}
more:;
MDBX_node *leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
olddata.iov_len = NODEDSZ(leaf);
olddata.iov_base = NODEDATA(leaf);
/* DB has dups? */
if (F_ISSET(mc->mc_db->md_flags, MDBX_DUPSORT)) {
/* Prepare (sub-)page/sub-DB to accept the new item, if needed.
* fp: old sub-page or a header faking it.
* mp: new (sub-)page. offset: growth in page size.
* xdata: node data with new page or DB. */
unsigned i, offset = 0;
MDBX_page *mp = fp = xdata.iov_base = env->me_pbuf;
mp->mp_pgno = mc->mc_pg[mc->mc_top]->mp_pgno;
/* Was a single item before, must convert now */
if (!F_ISSET(leaf->mn_flags, F_DUPDATA)) {
/* does data match? */
if (!mc->mc_dbx->md_dcmp(data, &olddata)) {
if (unlikely(flags & (MDBX_NODUPDATA | MDBX_APPENDDUP)))
return MDBX_KEYEXIST;
/* overwrite it */
goto current;
}
/* Just overwrite the current item */
if (flags & MDBX_CURRENT)
goto current;
/* Back up original data item */
dupdata_flag = 1;
dkey.iov_len = olddata.iov_len;
dkey.iov_base = memcpy(fp + 1, olddata.iov_base, olddata.iov_len);
/* Make sub-page header for the dup items, with dummy body */
fp->mp_flags = P_LEAF | P_DIRTY | P_SUBP;
fp->mp_lower = 0;
xdata.iov_len = PAGEHDRSZ + dkey.iov_len + data->iov_len;
if (mc->mc_db->md_flags & MDBX_DUPFIXED) {
fp->mp_flags |= P_LEAF2;
fp->mp_leaf2_ksize = (uint16_t)data->iov_len;
xdata.iov_len += 2 * data->iov_len; /* leave space for 2 more */
} else {
xdata.iov_len += 2 * (sizeof(indx_t) + NODESIZE) +
(dkey.iov_len & 1) + (data->iov_len & 1);
}
fp->mp_upper = (uint16_t)(xdata.iov_len - PAGEHDRSZ);
olddata.iov_len = xdata.iov_len; /* pretend olddata is fp */
} else if (leaf->mn_flags & F_SUBDATA) {
/* Data is on sub-DB, just store it */
flags |= F_DUPDATA | F_SUBDATA;
goto put_sub;
} else {
/* Data is on sub-page */
fp = olddata.iov_base;
switch (flags) {
default:
if (!(mc->mc_db->md_flags & MDBX_DUPFIXED)) {
offset = EVEN(NODESIZE + sizeof(indx_t) + data->iov_len);
break;
}
offset = fp->mp_leaf2_ksize;
if (SIZELEFT(fp) < offset) {
offset *= 4; /* space for 4 more */
break;
}
/* FALLTHRU: Big enough MDBX_DUPFIXED sub-page */
__fallthrough;
case MDBX_CURRENT | MDBX_NODUPDATA:
case MDBX_CURRENT:
fp->mp_flags |= P_DIRTY;
fp->mp_pgno = mp->mp_pgno;
mc->mc_xcursor->mx_cursor.mc_pg[0] = fp;
flags |= F_DUPDATA;
goto put_sub;
}
xdata.iov_len = olddata.iov_len + offset;
}
fp_flags = fp->mp_flags;
if (NODESIZE + NODEKSZ(leaf) + xdata.iov_len > env->me_nodemax) {
/* Too big for a sub-page, convert to sub-DB */
fp_flags &= ~P_SUBP;
prep_subDB:
dummy.md_xsize = 0;
dummy.md_flags = 0;
if (mc->mc_db->md_flags & MDBX_DUPFIXED) {
fp_flags |= P_LEAF2;
dummy.md_xsize = fp->mp_leaf2_ksize;
dummy.md_flags = MDBX_DUPFIXED;
if (mc->mc_db->md_flags & MDBX_INTEGERDUP)
dummy.md_flags |= MDBX_INTEGERKEY;
}
dummy.md_depth = 1;
dummy.md_branch_pages = 0;
dummy.md_leaf_pages = 1;
dummy.md_overflow_pages = 0;
dummy.md_entries = NUMKEYS(fp);
xdata.iov_len = sizeof(MDBX_db);
xdata.iov_base = &dummy;
if ((rc = mdbx_page_alloc(mc, 1, &mp, MDBX_ALLOC_ALL)))
return rc;
mc->mc_db->md_leaf_pages += 1;
mdbx_cassert(mc, env->me_psize > olddata.iov_len);
offset = env->me_psize - (unsigned)olddata.iov_len;
flags |= F_DUPDATA | F_SUBDATA;
dummy.md_root = mp->mp_pgno;
dummy.md_seq = dummy.md_merkle = 0;
sub_root = mp;
}
if (mp != fp) {
mp->mp_flags = fp_flags | P_DIRTY;
mp->mp_leaf2_ksize = fp->mp_leaf2_ksize;
mp->mp_lower = fp->mp_lower;
mdbx_cassert(mc, fp->mp_upper + offset <= UINT16_MAX);
mp->mp_upper = (indx_t)(fp->mp_upper + offset);
if (unlikely(fp_flags & P_LEAF2)) {
memcpy(PAGEDATA(mp), PAGEDATA(fp), NUMKEYS(fp) * fp->mp_leaf2_ksize);
} else {
memcpy((char *)mp + mp->mp_upper + PAGEHDRSZ,
(char *)fp + fp->mp_upper + PAGEHDRSZ,
olddata.iov_len - fp->mp_upper - PAGEHDRSZ);
memcpy((char *)(&mp->mp_ptrs), (char *)(&fp->mp_ptrs),
NUMKEYS(fp) * sizeof(mp->mp_ptrs[0]));
for (i = 0; i < NUMKEYS(fp); i++) {
mdbx_cassert(mc, mp->mp_ptrs[i] + offset <= UINT16_MAX);
mp->mp_ptrs[i] += (indx_t)offset;
}
}
}
rdata = &xdata;
flags |= F_DUPDATA;
do_sub = true;
if (!insert_key)
mdbx_node_del(mc, 0);
goto new_sub;
}
current:
/* MDBX passes F_SUBDATA in 'flags' to write a DB record */
if (unlikely((leaf->mn_flags ^ flags) & F_SUBDATA))
return MDBX_INCOMPATIBLE;
/* overflow page overwrites need special handling */
if (F_ISSET(leaf->mn_flags, F_BIGDATA)) {
MDBX_page *omp;
pgno_t pg;
int level, ovpages,
dpages = (LEAFSIZE(key, data) > env->me_nodemax)
? OVPAGES(env, data->iov_len)
: 0;
memcpy(&pg, olddata.iov_base, sizeof(pg));
if (unlikely((rc2 = mdbx_page_get(mc, pg, &omp, &level)) != 0))
return rc2;
ovpages = omp->mp_pages;
/* Is the ov page large enough? */
if (unlikely(mc->mc_flags & C_GCFREEZE)
? ovpages >= dpages
: ovpages ==
/* LY: add configurable threshold to keep reserve space */
dpages) {
if (!IS_DIRTY(omp) && (level || (env->me_flags & MDBX_WRITEMAP))) {
rc = mdbx_page_unspill(mc->mc_txn, omp, &omp);
if (unlikely(rc))
return rc;
level = 0; /* dirty in this txn or clean */
}
/* Is it dirty? */
if (IS_DIRTY(omp)) {
/* yes, overwrite it. Note in this case we don't
* bother to try shrinking the page if the new data
* is smaller than the overflow threshold. */
if (unlikely(level > 1)) {
/* It is writable only in a parent txn */
MDBX_page *np = mdbx_page_malloc(mc->mc_txn, ovpages);
if (unlikely(!np))
return MDBX_ENOMEM;
/* Note - this page is already counted in parent's dirtyroom */
rc2 = mdbx_dpl_insert(mc->mc_txn->mt_rw_dirtylist, pg, np);
if (unlikely(rc2 != MDBX_SUCCESS)) {
rc = rc2;
mdbx_dpage_free(env, np, ovpages);
goto fail;
}
/* Currently we make the page look as with put() in the
* parent txn, in case the user peeks at MDBX_RESERVEd
* or unused parts. Some users treat ovpages specially. */
const size_t whole = pgno2bytes(env, ovpages);
/* Skip the part where MDBX will put *data.
* Copy end of page, adjusting alignment so
* compiler may copy words instead of bytes. */
const size_t off =
(PAGEHDRSZ + data->iov_len) & -(intptr_t)sizeof(size_t);
memcpy((size_t *)((char *)np + off), (size_t *)((char *)omp + off),
whole - off);
memcpy(np, omp, PAGEHDRSZ); /* Copy header of page */
omp = np;
}
SETDSZ(leaf, data->iov_len);
if (F_ISSET(flags, MDBX_RESERVE))
data->iov_base = PAGEDATA(omp);
else
memcpy(PAGEDATA(omp), data->iov_base, data->iov_len);
if (mdbx_audit_enabled()) {
int err = mdbx_cursor_check(mc, false);
if (unlikely(err != MDBX_SUCCESS))
return err;
}
return MDBX_SUCCESS;
}
}
if ((rc2 = mdbx_ovpage_free(mc, omp)) != MDBX_SUCCESS)
return rc2;
} else if (data->iov_len == olddata.iov_len) {
mdbx_cassert(mc, EVEN(key->iov_len) == EVEN(leaf->mn_ksize));
/* same size, just replace it. Note that we could
* also reuse this node if the new data is smaller,
* but instead we opt to shrink the node in that case. */
if (F_ISSET(flags, MDBX_RESERVE))
data->iov_base = olddata.iov_base;
else if (!(mc->mc_flags & C_SUB))
memcpy(olddata.iov_base, data->iov_base, data->iov_len);
else {
mdbx_cassert(mc, NUMKEYS(mc->mc_pg[mc->mc_top]) == 1);
mdbx_cassert(mc, PAGETYPE(mc->mc_pg[mc->mc_top]) == P_LEAF);
mdbx_cassert(mc, NODEDSZ(leaf) == 0);
mdbx_cassert(mc, leaf->mn_flags == 0);
mdbx_cassert(mc, key->iov_len < UINT16_MAX);
leaf->mn_ksize = (uint16_t)key->iov_len;
memcpy(NODEKEY(leaf), key->iov_base, key->iov_len);
mdbx_cassert(mc, (char *)NODEKEY(leaf) + NODEDSZ(leaf) <
(char *)(mc->mc_pg[mc->mc_top]) + env->me_psize);
goto fix_parent;
}
if (mdbx_audit_enabled()) {
int err = mdbx_cursor_check(mc, false);
if (unlikely(err != MDBX_SUCCESS))
return err;
}
return MDBX_SUCCESS;
}
mdbx_node_del(mc, 0);
}
rdata = data;
new_sub:
nflags = flags & NODE_ADD_FLAGS;
nsize = IS_LEAF2(mc->mc_pg[mc->mc_top]) ? key->iov_len
: mdbx_leaf_size(env, key, rdata);
if (SIZELEFT(mc->mc_pg[mc->mc_top]) < nsize) {
if ((flags & (F_DUPDATA | F_SUBDATA)) == F_DUPDATA)
nflags &= ~MDBX_APPEND; /* sub-page may need room to grow */
if (!insert_key)
nflags |= MDBX_SPLIT_REPLACE;
rc = mdbx_page_split(mc, key, rdata, P_INVALID, nflags);
if (rc == MDBX_SUCCESS && mdbx_audit_enabled())
rc = mdbx_cursor_check(mc, false);
} else {
/* There is room already in this leaf page. */
if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
mdbx_cassert(mc, (nflags & (F_BIGDATA | F_SUBDATA | F_DUPDATA)) == 0 &&
rdata->iov_len == 0);
rc = mdbx_node_add_leaf2(mc, mc->mc_ki[mc->mc_top], key);
} else
rc = mdbx_node_add_leaf(mc, mc->mc_ki[mc->mc_top], key, rdata, nflags);
if (likely(rc == 0)) {
/* Adjust other cursors pointing to mp */
MDBX_cursor *m2, *m3;
MDBX_dbi dbi = mc->mc_dbi;
unsigned i = mc->mc_top;
MDBX_page *mp = mc->mc_pg[i];
for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2 = m2->mc_next) {
m3 = (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
if (m3 == mc || m3->mc_snum < mc->mc_snum || m3->mc_pg[i] != mp)
continue;
if (m3->mc_ki[i] >= mc->mc_ki[i] && insert_key) {
m3->mc_ki[i]++;
}
if (XCURSOR_INITED(m3))
XCURSOR_REFRESH(m3, mp, m3->mc_ki[i]);
}
}
}
if (likely(rc == MDBX_SUCCESS)) {
/* Now store the actual data in the child DB. Note that we're
* storing the user data in the keys field, so there are strict
* size limits on dupdata. The actual data fields of the child
* DB are all zero size. */
if (do_sub) {
int xflags;
size_t ecount;
put_sub:
xdata.iov_len = 0;
xdata.iov_base = "";
MDBX_node *leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
if (flags & MDBX_CURRENT) {
xflags = (flags & MDBX_NODUPDATA)
? MDBX_CURRENT | MDBX_NOOVERWRITE | MDBX_NOSPILL
: MDBX_CURRENT | MDBX_NOSPILL;
} else {
rc2 = mdbx_xcursor_init1(mc, leaf);
if (unlikely(rc2 != MDBX_SUCCESS))
return rc2;
xflags = (flags & MDBX_NODUPDATA) ? MDBX_NOOVERWRITE | MDBX_NOSPILL
: MDBX_NOSPILL;
}
if (sub_root)
mc->mc_xcursor->mx_cursor.mc_pg[0] = sub_root;
/* converted, write the original data first */
if (dupdata_flag) {
rc = mdbx_cursor_put(&mc->mc_xcursor->mx_cursor, &dkey, &xdata, xflags);
if (unlikely(rc))
goto bad_sub;
/* we've done our job */
dkey.iov_len = 0;
}
if (!(leaf->mn_flags & F_SUBDATA) || sub_root) {
/* Adjust other cursors pointing to mp */
MDBX_cursor *m2;
MDBX_xcursor *mx = mc->mc_xcursor;
unsigned i = mc->mc_top;
MDBX_page *mp = mc->mc_pg[i];
const int nkeys = NUMKEYS(mp);
for (m2 = mc->mc_txn->mt_cursors[mc->mc_dbi]; m2; m2 = m2->mc_next) {
if (m2 == mc || m2->mc_snum < mc->mc_snum)
continue;
if (!(m2->mc_flags & C_INITIALIZED))
continue;
if (m2->mc_pg[i] == mp) {
if (m2->mc_ki[i] == mc->mc_ki[i]) {
rc2 = mdbx_xcursor_init2(m2, mx, dupdata_flag);
if (unlikely(rc2 != MDBX_SUCCESS))
return rc2;
} else if (!insert_key && m2->mc_ki[i] < nkeys) {
XCURSOR_REFRESH(m2, mp, m2->mc_ki[i]);
}
}
}
}
mdbx_cassert(mc, mc->mc_xcursor->mx_db.md_entries < SIZE_MAX);
ecount = (size_t)mc->mc_xcursor->mx_db.md_entries;
if (flags & MDBX_APPENDDUP)
xflags |= MDBX_APPEND;
rc = mdbx_cursor_put(&mc->mc_xcursor->mx_cursor, data, &xdata, xflags);
if (flags & F_SUBDATA) {
void *db = NODEDATA(leaf);
memcpy(db, &mc->mc_xcursor->mx_db, sizeof(MDBX_db));
}
insert_data = (ecount != (size_t)mc->mc_xcursor->mx_db.md_entries);
}
/* Increment count unless we just replaced an existing item. */
if (insert_data)
mc->mc_db->md_entries++;
if (insert_key) {
/* Invalidate txn if we created an empty sub-DB */
if (unlikely(rc))
goto bad_sub;
/* If we succeeded and the key didn't exist before,
* make sure the cursor is marked valid. */
mc->mc_flags |= C_INITIALIZED;
}
if (flags & MDBX_MULTIPLE) {
if (!rc) {
mcount++;
/* let caller know how many succeeded, if any */
data[1].iov_len = mcount;
if (mcount < dcount) {
data[0].iov_base = (char *)data[0].iov_base + data[0].iov_len;
insert_key = insert_data = false;
goto more;
}
}
}
if (rc == MDBX_SUCCESS && mdbx_audit_enabled())
rc = mdbx_cursor_check(mc, false);
return rc;
bad_sub:
if (unlikely(rc == MDBX_KEYEXIST))
mdbx_error("unexpected %s", "MDBX_KEYEXIST");
/* should not happen, we deleted that item */
rc = MDBX_PROBLEM;
}
fail:
mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
return rc;
}
int mdbx_cursor_del(MDBX_cursor *mc, unsigned flags) {
MDBX_node *leaf;
MDBX_page *mp;
int rc;
if (unlikely(!mc))
return MDBX_EINVAL;
if (unlikely(mc->mc_signature != MDBX_MC_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(mc->mc_txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_BLOCKED)))
return (mc->mc_txn->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EACCESS
: MDBX_BAD_TXN;
if (unlikely(!(mc->mc_flags & C_INITIALIZED)))
return MDBX_EINVAL;
if (unlikely(mc->mc_ki[mc->mc_top] >= NUMKEYS(mc->mc_pg[mc->mc_top])))
return MDBX_NOTFOUND;
if (unlikely(!(flags & MDBX_NOSPILL) &&
(rc = mdbx_page_spill(mc, NULL, NULL))))
return rc;
rc = mdbx_cursor_touch(mc);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
mp = mc->mc_pg[mc->mc_top];
if (IS_LEAF2(mp))
goto del_key;
leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
if (flags & MDBX_NODUPDATA) {
/* mdbx_cursor_del0() will subtract the final entry */
mc->mc_db->md_entries -= mc->mc_xcursor->mx_db.md_entries - 1;
mc->mc_xcursor->mx_cursor.mc_flags &= ~C_INITIALIZED;
} else {
if (!F_ISSET(leaf->mn_flags, F_SUBDATA)) {
mc->mc_xcursor->mx_cursor.mc_pg[0] = NODEDATA(leaf);
}
rc = mdbx_cursor_del(&mc->mc_xcursor->mx_cursor, MDBX_NOSPILL);
if (unlikely(rc))
return rc;
/* If sub-DB still has entries, we're done */
if (mc->mc_xcursor->mx_db.md_entries) {
if (leaf->mn_flags & F_SUBDATA) {
/* update subDB info */
void *db = NODEDATA(leaf);
memcpy(db, &mc->mc_xcursor->mx_db, sizeof(MDBX_db));
} else {
MDBX_cursor *m2;
/* shrink fake page */
mdbx_node_shrink(mp, mc->mc_ki[mc->mc_top]);
leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
mc->mc_xcursor->mx_cursor.mc_pg[0] = NODEDATA(leaf);
/* fix other sub-DB cursors pointed at fake pages on this page */
for (m2 = mc->mc_txn->mt_cursors[mc->mc_dbi]; m2; m2 = m2->mc_next) {
if (m2 == mc || m2->mc_snum < mc->mc_snum)
continue;
if (!(m2->mc_flags & C_INITIALIZED))
continue;
if (m2->mc_pg[mc->mc_top] == mp) {
MDBX_node *n2 = leaf;
if (m2->mc_ki[mc->mc_top] >= NUMKEYS(mp))
continue;
if (m2->mc_ki[mc->mc_top] != mc->mc_ki[mc->mc_top]) {
n2 = NODEPTR(mp, m2->mc_ki[mc->mc_top]);
if (n2->mn_flags & F_SUBDATA)
continue;
}
m2->mc_xcursor->mx_cursor.mc_pg[0] = NODEDATA(n2);
}
}
}
mc->mc_db->md_entries--;
mdbx_cassert(mc, mc->mc_db->md_entries > 0 && mc->mc_db->md_depth > 0 &&
mc->mc_db->md_root != P_INVALID);
return rc;
} else {
mc->mc_xcursor->mx_cursor.mc_flags &= ~C_INITIALIZED;
}
/* otherwise fall thru and delete the sub-DB */
}
if (leaf->mn_flags & F_SUBDATA) {
/* add all the child DB's pages to the free list */
mc->mc_db->md_branch_pages -= mc->mc_xcursor->mx_db.md_branch_pages;
mc->mc_db->md_leaf_pages -= mc->mc_xcursor->mx_db.md_leaf_pages;
mc->mc_db->md_overflow_pages -= mc->mc_xcursor->mx_db.md_overflow_pages;
rc = mdbx_drop0(&mc->mc_xcursor->mx_cursor, 0);
if (unlikely(rc))
goto fail;
}
}
/* MDBX passes F_SUBDATA in 'flags' to delete a DB record */
else if (unlikely((leaf->mn_flags ^ flags) & F_SUBDATA)) {
rc = MDBX_INCOMPATIBLE;
goto fail;
}
/* add overflow pages to free list */
if (F_ISSET(leaf->mn_flags, F_BIGDATA)) {
MDBX_page *omp;
pgno_t pg;
memcpy(&pg, NODEDATA(leaf), sizeof(pg));
if (unlikely((rc = mdbx_page_get(mc, pg, &omp, NULL)) ||
(rc = mdbx_ovpage_free(mc, omp))))
goto fail;
}
del_key:
return mdbx_cursor_del0(mc);
fail:
mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
return rc;
}
/* Allocate and initialize new pages for a database.
* Set MDBX_TXN_ERROR on failure.
*
* [in] mc a cursor on the database being added to.
* [in] flags flags defining what type of page is being allocated.
* [in] num the number of pages to allocate. This is usually 1,
* unless allocating overflow pages for a large record.
* [out] mp Address of a page, or NULL on failure.
*
* Returns 0 on success, non-zero on failure. */
static int mdbx_page_new(MDBX_cursor *mc, unsigned flags, unsigned num,
MDBX_page **mp) {
MDBX_page *np;
int rc;
if (unlikely((rc = mdbx_page_alloc(mc, num, &np, MDBX_ALLOC_ALL))))
return rc;
mdbx_debug("allocated new page #%" PRIaPGNO ", size %u", np->mp_pgno,
mc->mc_txn->mt_env->me_psize);
np->mp_flags = (uint16_t)(flags | P_DIRTY);
np->mp_lower = 0;
np->mp_upper = (indx_t)(mc->mc_txn->mt_env->me_psize - PAGEHDRSZ);
if (IS_BRANCH(np))
mc->mc_db->md_branch_pages++;
else if (IS_LEAF(np))
mc->mc_db->md_leaf_pages++;
else {
mdbx_cassert(mc, IS_OVERFLOW(np));
mc->mc_db->md_overflow_pages += num;
np->mp_pages = num;
}
if (unlikely(mc->mc_flags & C_SUB)) {
MDBX_db *outer = mdbx_outer_db(mc);
if (IS_BRANCH(np))
outer->md_branch_pages++;
else if (IS_LEAF(np))
outer->md_leaf_pages++;
else {
mdbx_cassert(mc, IS_OVERFLOW(np));
outer->md_overflow_pages += num;
}
}
*mp = np;
return MDBX_SUCCESS;
}
/* Calculate the size of a leaf node.
*
* The size depends on the environment's page size; if a data item
* is too large it will be put onto an overflow page and the node
* size will only include the key and not the data. Sizes are always
* rounded up to an even number of bytes, to guarantee 2-byte alignment
* of the MDBX_node headers.
*
* [in] env The environment handle.
* [in] key The key for the node.
* [in] data The data for the node.
*
* Returns The number of bytes needed to store the node. */
static __inline size_t mdbx_leaf_size(MDBX_env *env, const MDBX_val *key,
const MDBX_val *data) {
size_t sz = LEAFSIZE(key, data);
if (sz > env->me_nodemax) {
/* put on overflow page */
sz = sz - data->iov_len + sizeof(pgno_t);
}
return EVEN(sz) + sizeof(indx_t);
}
/* Calculate the size of a branch node.
*
* The size should depend on the environment's page size but since
* we currently don't support spilling large keys onto overflow
* pages, it's simply the size of the MDBX_node header plus the
* size of the key. Sizes are always rounded up to an even number
* of bytes, to guarantee 2-byte alignment of the MDBX_node headers.
*
* [in] env The environment handle.
* [in] key The key for the node.
*
* Returns The number of bytes needed to store the node. */
static __inline size_t mdbx_branch_size(MDBX_env *env, const MDBX_val *key) {
size_t sz = INDXSIZE(key);
if (unlikely(sz > env->me_nodemax)) {
/* put on overflow page */
/* not implemented */
mdbx_assert_fail(env, "INDXSIZE(key) <= env->me_nodemax", __FUNCTION__,
__LINE__);
sz = sz - key->iov_len + sizeof(pgno_t);
}
return EVEN(sz) + sizeof(indx_t);
}
static int __must_check_result mdbx_node_add_leaf2(MDBX_cursor *mc,
unsigned indx,
const MDBX_val *key) {
MDBX_page *mp = mc->mc_pg[mc->mc_top];
DKBUF;
mdbx_debug("add to leaf2-%spage %" PRIaPGNO " index %i, "
" key size %" PRIuPTR " [%s]",
IS_SUBP(mp) ? "sub-" : "", mp->mp_pgno, indx,
key ? key->iov_len : 0, DKEY(key));
mdbx_cassert(mc, key);
mdbx_cassert(mc, PAGETYPE(mp) == (P_LEAF | P_LEAF2));
const unsigned ksize = mc->mc_db->md_xsize;
mdbx_cassert(mc, ksize == key->iov_len);
const int room = SIZELEFT(mp);
mdbx_cassert(mc, room >= (int)ksize);
if (unlikely(room < (int)ksize)) {
bailout:
mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
return MDBX_PAGE_FULL;
}
char *const ptr = LEAF2KEY(mp, indx, ksize);
mdbx_cassert(mc, NUMKEYS(mp) >= indx);
if (unlikely(NUMKEYS(mp) < indx))
goto bailout;
const unsigned diff = NUMKEYS(mp) - indx;
if (likely(diff > 0))
/* Move higher keys up one slot. */
memmove(ptr + ksize, ptr, diff * ksize);
/* insert new key */
memcpy(ptr, key->iov_base, ksize);
/* Just using these for counting */
mdbx_cassert(mc, UINT16_MAX - mp->mp_lower >= (int)sizeof(indx_t));
mp->mp_lower += sizeof(indx_t);
mdbx_cassert(mc, mp->mp_upper >= ksize - sizeof(indx_t));
mp->mp_upper -= (indx_t)(ksize - sizeof(indx_t));
mdbx_cassert(mc,
mp->mp_upper >= mp->mp_lower &&
PAGEHDRSZ + mp->mp_upper <= mc->mc_txn->mt_env->me_psize);
return MDBX_SUCCESS;
}
static int __must_check_result mdbx_node_add_branch(MDBX_cursor *mc,
unsigned indx,
const MDBX_val *key,
pgno_t pgno) {
MDBX_page *mp = mc->mc_pg[mc->mc_top];
DKBUF;
mdbx_debug("add to branch-%spage %" PRIaPGNO " index %i, node-pgno %" PRIaPGNO
" key size %" PRIuPTR " [%s]",
IS_SUBP(mp) ? "sub-" : "", mp->mp_pgno, indx, pgno,
key ? key->iov_len : 0, DKEY(key));
mdbx_cassert(mc, PAGETYPE(mp) == P_BRANCH);
STATIC_ASSERT(NODESIZE % 2 == 0);
const size_t room = SIZELEFT(mp);
const size_t node_size =
likely(key != NULL) ? NODESIZE + EVEN(key->iov_len) : NODESIZE;
mdbx_cassert(mc, mdbx_branch_size(mc->mc_txn->mt_env, key) ==
node_size + sizeof(indx_t));
mdbx_cassert(mc, room >= node_size + sizeof(indx_t));
if (unlikely(room < node_size + sizeof(indx_t))) {
bailout:
mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
return MDBX_PAGE_FULL;
}
const unsigned numkeys = NUMKEYS(mp);
mdbx_cassert(mc, numkeys >= indx);
if (unlikely(numkeys < indx))
goto bailout;
/* Move higher pointers up one slot. */
for (unsigned i = numkeys; i > indx; --i)
mp->mp_ptrs[i] = mp->mp_ptrs[i - 1];
/* Adjust free space offsets. */
const size_t ofs = mp->mp_upper - node_size;
mdbx_cassert(mc, ofs >= mp->mp_lower + sizeof(indx_t));
mdbx_cassert(mc, ofs <= UINT16_MAX);
mp->mp_ptrs[indx] = (uint16_t)ofs;
mp->mp_upper = (uint16_t)ofs;
mp->mp_lower += sizeof(indx_t);
/* Write the node data. */
MDBX_node *node = NODEPTR(mp, indx);
SETPGNO(node, pgno);
node->mn_ksize = 0;
node->mn_flags = 0;
if (likely(key != NULL)) {
node->mn_ksize = (uint16_t)key->iov_len;
memcpy(NODEKEY(node), key->iov_base, key->iov_len);
}
mdbx_cassert(mc,
mp->mp_upper >= mp->mp_lower &&
PAGEHDRSZ + mp->mp_upper <= mc->mc_txn->mt_env->me_psize);
return MDBX_SUCCESS;
}
static int __must_check_result mdbx_node_add_leaf(MDBX_cursor *mc,
unsigned indx,
const MDBX_val *key,
MDBX_val *data,
unsigned flags) {
MDBX_page *mp = mc->mc_pg[mc->mc_top];
DKBUF;
mdbx_debug("add to leaf-%spage %" PRIaPGNO " index %i, data size %" PRIuPTR
" key size %" PRIuPTR " [%s]",
IS_SUBP(mp) ? "sub-" : "", mp->mp_pgno, indx,
data ? data->iov_len : 0, key ? key->iov_len : 0, DKEY(key));
mdbx_cassert(mc, key != NULL && data != NULL);
mdbx_cassert(mc, PAGETYPE(mp) == P_LEAF);
MDBX_page *largepage = NULL;
const size_t room = SIZELEFT(mp);
size_t node_size = NODESIZE + key->iov_len;
if (unlikely(flags & F_BIGDATA)) {
/* Data already on overflow page. */
STATIC_ASSERT(sizeof(pgno_t) % 2 == 0);
node_size += sizeof(pgno_t);
} else if (unlikely(node_size + data->iov_len >
mc->mc_txn->mt_env->me_nodemax)) {
const pgno_t ovpages = OVPAGES(mc->mc_txn->mt_env, data->iov_len);
/* Put data on overflow page. */
mdbx_debug("data size is %" PRIuPTR ", node would be %" PRIuPTR
", put data on %u-overflow page(s)",
data->iov_len, node_size + data->iov_len, ovpages);
int rc = mdbx_page_new(mc, P_OVERFLOW, ovpages, &largepage);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
mdbx_debug("allocated overflow page %" PRIaPGNO, largepage->mp_pgno);
flags |= F_BIGDATA;
node_size += sizeof(pgno_t);
mdbx_cassert(mc, mdbx_leaf_size(mc->mc_txn->mt_env, key, data) ==
EVEN(node_size) + sizeof(indx_t));
} else {
node_size += data->iov_len;
mdbx_cassert(mc, mdbx_leaf_size(mc->mc_txn->mt_env, key, data) ==
EVEN(node_size) + sizeof(indx_t));
}
node_size = EVEN(node_size);
mdbx_cassert(mc, room >= node_size + sizeof(indx_t));
if (unlikely(room < node_size + sizeof(indx_t))) {
bailout:
mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
return MDBX_PAGE_FULL;
}
const unsigned numkeys = NUMKEYS(mp);
mdbx_cassert(mc, numkeys >= indx);
if (unlikely(numkeys < indx))
goto bailout;
/* Move higher pointers up one slot. */
for (unsigned i = numkeys; i > indx; --i)
mp->mp_ptrs[i] = mp->mp_ptrs[i - 1];
/* Adjust free space offsets. */
const size_t ofs = mp->mp_upper - node_size;
mdbx_cassert(mc, ofs >= mp->mp_lower + sizeof(indx_t));
mdbx_cassert(mc, ofs <= UINT16_MAX);
mp->mp_ptrs[indx] = (uint16_t)ofs;
mp->mp_upper = (uint16_t)ofs;
mp->mp_lower += sizeof(indx_t);
/* Write the node data. */
MDBX_node *node = NODEPTR(mp, indx);
node->mn_ksize = (uint16_t)key->iov_len;
node->mn_flags = (uint16_t)flags;
SETDSZ(node, data->iov_len);
memcpy(NODEKEY(node), key->iov_base, key->iov_len);
void *nodedata = NODEDATA(node);
if (likely(largepage == NULL)) {
if (unlikely(flags & F_BIGDATA))
memcpy(nodedata, data->iov_base, sizeof(pgno_t));
else if (unlikely(flags & MDBX_RESERVE))
data->iov_base = nodedata;
else if (likely(nodedata != data->iov_base))
memcpy(nodedata, data->iov_base, data->iov_len);
} else {
memcpy(nodedata, &largepage->mp_pgno, sizeof(pgno_t));
nodedata = PAGEDATA(largepage);
if (unlikely(flags & MDBX_RESERVE))
data->iov_base = nodedata;
else if (likely(nodedata != data->iov_base))
memcpy(nodedata, data->iov_base, data->iov_len);
}
mdbx_cassert(mc,
mp->mp_upper >= mp->mp_lower &&
PAGEHDRSZ + mp->mp_upper <= mc->mc_txn->mt_env->me_psize);
return MDBX_SUCCESS;
}
/* Delete the specified node from a page.
* [in] mc Cursor pointing to the node to delete.
* [in] ksize The size of a node. Only used if the page is
* part of a MDBX_DUPFIXED database. */
static void mdbx_node_del(MDBX_cursor *mc, size_t ksize) {
MDBX_page *mp = mc->mc_pg[mc->mc_top];
indx_t indx = mc->mc_ki[mc->mc_top];
indx_t i, j, numkeys, ptr;
MDBX_node *node;
char *base;
mdbx_debug("delete node %u on %s page %" PRIaPGNO, indx,
IS_LEAF(mp) ? "leaf" : "branch", mp->mp_pgno);
numkeys = NUMKEYS(mp);
mdbx_cassert(mc, indx < numkeys);
if (IS_LEAF2(mp)) {
mdbx_cassert(mc, ksize >= sizeof(indx_t));
unsigned diff = numkeys - 1 - indx;
base = LEAF2KEY(mp, indx, ksize);
if (diff)
memmove(base, base + ksize, diff * ksize);
mdbx_cassert(mc, mp->mp_lower >= sizeof(indx_t));
mp->mp_lower -= sizeof(indx_t);
mdbx_cassert(mc,
(size_t)UINT16_MAX - mp->mp_upper >= ksize - sizeof(indx_t));
mp->mp_upper += (indx_t)(ksize - sizeof(indx_t));
return;
}
node = NODEPTR(mp, indx);
size_t sz = NODESIZE + node->mn_ksize;
if (IS_LEAF(mp)) {
if (F_ISSET(node->mn_flags, F_BIGDATA))
sz += sizeof(pgno_t);
else
sz += NODEDSZ(node);
}
sz = EVEN(sz);
ptr = mp->mp_ptrs[indx];
for (i = j = 0; i < numkeys; i++) {
if (i != indx) {
mp->mp_ptrs[j] = mp->mp_ptrs[i];
if (mp->mp_ptrs[i] < ptr) {
mdbx_cassert(mc, (size_t)UINT16_MAX - mp->mp_ptrs[j] >= sz);
mp->mp_ptrs[j] += (indx_t)sz;
}
j++;
}
}
base = (char *)mp + mp->mp_upper + PAGEHDRSZ;
memmove(base + sz, base, ptr - mp->mp_upper);
mdbx_cassert(mc, mp->mp_lower >= sizeof(indx_t));
mp->mp_lower -= sizeof(indx_t);
mdbx_cassert(mc, (size_t)UINT16_MAX - mp->mp_upper >= sz);
mp->mp_upper += (indx_t)sz;
}
/* Compact the main page after deleting a node on a subpage.
* [in] mp The main page to operate on.
* [in] indx The index of the subpage on the main page. */
static void mdbx_node_shrink(MDBX_page *mp, unsigned indx) {
MDBX_node *node;
MDBX_page *sp, *xp;
char *base;
size_t nsize, delta, len, ptr;
int i;
node = NODEPTR(mp, indx);
sp = (MDBX_page *)NODEDATA(node);
delta = SIZELEFT(sp);
assert(delta > 0);
/* Prepare to shift upward, set len = length(subpage part to shift) */
if (IS_LEAF2(sp)) {
delta &= /* do not make the node uneven-sized */ ~1u;
if (unlikely(delta) == 0)
return;
nsize = NODEDSZ(node) - delta;
assert(nsize % 1 == 0);
len = nsize;
} else {
xp = (MDBX_page *)((char *)sp + delta); /* destination subpage */
for (i = NUMKEYS(sp); --i >= 0;) {
assert(sp->mp_ptrs[i] >= delta);
xp->mp_ptrs[i] = (indx_t)(sp->mp_ptrs[i] - delta);
}
nsize = NODEDSZ(node) - delta;
len = PAGEHDRSZ;
}
sp->mp_upper = sp->mp_lower;
sp->mp_pgno = mp->mp_pgno;
SETDSZ(node, nsize);
/* Shift <lower nodes...initial part of subpage> upward */
base = (char *)mp + mp->mp_upper + PAGEHDRSZ;
memmove(base + delta, base, (char *)sp + len - base);
ptr = mp->mp_ptrs[indx];
for (i = NUMKEYS(mp); --i >= 0;) {
if (mp->mp_ptrs[i] <= ptr) {
assert((size_t)UINT16_MAX - mp->mp_ptrs[i] >= delta);
mp->mp_ptrs[i] += (indx_t)delta;
}
}
assert((size_t)UINT16_MAX - mp->mp_upper >= delta);
mp->mp_upper += (indx_t)delta;
}
/* Initial setup of a sorted-dups cursor.
*
* Sorted duplicates are implemented as a sub-database for the given key.
* The duplicate data items are actually keys of the sub-database.
* Operations on the duplicate data items are performed using a sub-cursor
* initialized when the sub-database is first accessed. This function does
* the preliminary setup of the sub-cursor, filling in the fields that
* depend only on the parent DB.
*
* [in] mc The main cursor whose sorted-dups cursor is to be initialized. */
static int mdbx_xcursor_init0(MDBX_cursor *mc) {
MDBX_xcursor *mx = mc->mc_xcursor;
if (unlikely(mx == nullptr))
return MDBX_CORRUPTED;
mx->mx_cursor.mc_xcursor = NULL;
mx->mx_cursor.mc_txn = mc->mc_txn;
mx->mx_cursor.mc_db = &mx->mx_db;
mx->mx_cursor.mc_dbx = &mx->mx_dbx;
mx->mx_cursor.mc_dbi = mc->mc_dbi;
mx->mx_cursor.mc_dbflag = &mx->mx_dbflag;
mx->mx_cursor.mc_snum = 0;
mx->mx_cursor.mc_top = 0;
mx->mx_cursor.mc_flags = C_SUB;
mx->mx_dbx.md_name.iov_len = 0;
mx->mx_dbx.md_name.iov_base = NULL;
mx->mx_dbx.md_cmp = mc->mc_dbx->md_dcmp;
mx->mx_dbx.md_dcmp = NULL;
return MDBX_SUCCESS;
}
/* Final setup of a sorted-dups cursor.
* Sets up the fields that depend on the data from the main cursor.
* [in] mc The main cursor whose sorted-dups cursor is to be initialized.
* [in] node The data containing the MDBX_db record for the sorted-dup database.
*/
static int mdbx_xcursor_init1(MDBX_cursor *mc, MDBX_node *node) {
MDBX_xcursor *mx = mc->mc_xcursor;
if (unlikely(mx == nullptr))
return MDBX_CORRUPTED;
if (node->mn_flags & F_SUBDATA) {
memcpy(&mx->mx_db, NODEDATA(node), sizeof(MDBX_db));
mx->mx_cursor.mc_pg[0] = 0;
mx->mx_cursor.mc_snum = 0;
mx->mx_cursor.mc_top = 0;
mx->mx_cursor.mc_flags = C_SUB;
} else {
MDBX_page *fp = NODEDATA(node);
mx->mx_db.md_xsize = 0;
mx->mx_db.md_flags = 0;
mx->mx_db.md_depth = 1;
mx->mx_db.md_branch_pages = 0;
mx->mx_db.md_leaf_pages = 1;
mx->mx_db.md_overflow_pages = 0;
mx->mx_db.md_entries = NUMKEYS(fp);
mx->mx_db.md_root = fp->mp_pgno;
mx->mx_cursor.mc_snum = 1;
mx->mx_cursor.mc_top = 0;
mx->mx_cursor.mc_flags = C_INITIALIZED | C_SUB;
mx->mx_cursor.mc_pg[0] = fp;
mx->mx_cursor.mc_ki[0] = 0;
if (mc->mc_db->md_flags & MDBX_DUPFIXED) {
mx->mx_db.md_flags = MDBX_DUPFIXED;
mx->mx_db.md_xsize = fp->mp_leaf2_ksize;
if (mc->mc_db->md_flags & MDBX_INTEGERDUP)
mx->mx_db.md_flags |= MDBX_INTEGERKEY;
}
}
mdbx_debug("Sub-db -%u root page %" PRIaPGNO, mx->mx_cursor.mc_dbi,
mx->mx_db.md_root);
mx->mx_dbflag = DB_VALID | DB_USRVALID | DB_DUPDATA;
/* FIXME: #if UINT_MAX < SIZE_MAX
if (mx->mx_dbx.md_cmp == mdbx_cmp_int && mx->mx_db.md_pad ==
sizeof(size_t))
mx->mx_dbx.md_cmp = mdbx_cmp_clong;
#endif */
return MDBX_SUCCESS;
}
/* Fixup a sorted-dups cursor due to underlying update.
* Sets up some fields that depend on the data from the main cursor.
* Almost the same as init1, but skips initialization steps if the
* xcursor had already been used.
* [in] mc The main cursor whose sorted-dups cursor is to be fixed up.
* [in] src_mx The xcursor of an up-to-date cursor.
* [in] new_dupdata True if converting from a non-F_DUPDATA item. */
static int mdbx_xcursor_init2(MDBX_cursor *mc, MDBX_xcursor *src_mx,
int new_dupdata) {
MDBX_xcursor *mx = mc->mc_xcursor;
if (unlikely(mx == nullptr))
return MDBX_CORRUPTED;
if (new_dupdata) {
mx->mx_cursor.mc_snum = 1;
mx->mx_cursor.mc_top = 0;
mx->mx_cursor.mc_flags |= C_INITIALIZED;
mx->mx_cursor.mc_ki[0] = 0;
mx->mx_dbflag = DB_VALID | DB_USRVALID | DB_DUPDATA;
mx->mx_dbx.md_cmp = src_mx->mx_dbx.md_cmp;
} else if (!(mx->mx_cursor.mc_flags & C_INITIALIZED)) {
return MDBX_SUCCESS;
}
mx->mx_db = src_mx->mx_db;
mx->mx_cursor.mc_pg[0] = src_mx->mx_cursor.mc_pg[0];
mdbx_debug("Sub-db -%u root page %" PRIaPGNO, mx->mx_cursor.mc_dbi,
mx->mx_db.md_root);
return MDBX_SUCCESS;
}
/* Initialize a cursor for a given transaction and database. */
static int mdbx_cursor_init(MDBX_cursor *mc, MDBX_txn *txn, MDBX_dbi dbi) {
mc->mc_signature = MDBX_MC_SIGNATURE;
mc->mc_next = NULL;
mc->mc_backup = NULL;
mc->mc_dbi = dbi;
mc->mc_txn = txn;
mc->mc_db = &txn->mt_dbs[dbi];
mc->mc_dbx = &txn->mt_dbxs[dbi];
mc->mc_dbflag = &txn->mt_dbflags[dbi];
mc->mc_snum = 0;
mc->mc_top = 0;
mc->mc_pg[0] = 0;
mc->mc_flags = 0;
mc->mc_ki[0] = 0;
mc->mc_xcursor = NULL;
if (txn->mt_dbs[dbi].md_flags & MDBX_DUPSORT) {
STATIC_ASSERT(offsetof(MDBX_cursor_couple, outer) == 0);
MDBX_xcursor *mx = &container_of(mc, MDBX_cursor_couple, outer)->inner;
mdbx_tassert(txn, mx != NULL);
mx->mx_cursor.mc_signature = MDBX_MC_SIGNATURE;
mc->mc_xcursor = mx;
int rc = mdbx_xcursor_init0(mc);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
int rc = MDBX_SUCCESS;
if (unlikely(*mc->mc_dbflag & DB_STALE)) {
rc = mdbx_page_search(mc, NULL, MDBX_PS_ROOTONLY);
rc = (rc != MDBX_NOTFOUND) ? rc : MDBX_SUCCESS;
}
return rc;
}
int mdbx_cursor_open(MDBX_txn *txn, MDBX_dbi dbi, MDBX_cursor **ret) {
if (unlikely(!ret || !txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_VALID)))
return MDBX_EINVAL;
if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
if (unlikely(dbi == FREE_DBI && !F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY)))
return MDBX_EINVAL;
const size_t size = (txn->mt_dbs[dbi].md_flags & MDBX_DUPSORT)
? sizeof(MDBX_cursor_couple)
: sizeof(MDBX_cursor);
MDBX_cursor *mc;
if (likely((mc = mdbx_malloc(size)) != NULL)) {
int rc = mdbx_cursor_init(mc, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS)) {
mdbx_free(mc);
return rc;
}
if (txn->mt_cursors) {
mc->mc_next = txn->mt_cursors[dbi];
txn->mt_cursors[dbi] = mc;
mc->mc_flags |= C_UNTRACK;
}
} else {
return MDBX_ENOMEM;
}
*ret = mc;
return MDBX_SUCCESS;
}
int mdbx_cursor_renew(MDBX_txn *txn, MDBX_cursor *mc) {
if (unlikely(!mc || !txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return txn->mt_owner ? MDBX_THREAD_MISMATCH : MDBX_BAD_TXN;
if (unlikely(txn->mt_flags & (MDBX_TXN_FINISHED | MDBX_TXN_ERROR)))
return MDBX_BAD_TXN;
if (unlikely(mc->mc_signature != MDBX_MC_SIGNATURE &&
mc->mc_signature != MDBX_MC_READY4CLOSE))
return MDBX_EINVAL;
if (unlikely(!TXN_DBI_EXIST(txn, mc->mc_dbi, DB_VALID)))
return MDBX_EINVAL;
if (unlikely(mc->mc_backup))
return MDBX_EINVAL;
if (unlikely((mc->mc_flags & C_UNTRACK) || txn->mt_cursors)) {
MDBX_cursor **prev = &mc->mc_txn->mt_cursors[mc->mc_dbi];
while (*prev && *prev != mc)
prev = &(*prev)->mc_next;
if (*prev == mc)
*prev = mc->mc_next;
mc->mc_signature = MDBX_MC_READY4CLOSE;
}
if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
return mdbx_cursor_init(mc, txn, mc->mc_dbi);
}
/* Return the count of duplicate data items for the current key */
int mdbx_cursor_count(MDBX_cursor *mc, size_t *countp) {
if (unlikely(mc == NULL || countp == NULL))
return MDBX_EINVAL;
if (unlikely(mc->mc_signature != MDBX_MC_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(mc->mc_txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(mc->mc_txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
if (unlikely(!(mc->mc_flags & C_INITIALIZED)))
return MDBX_EINVAL;
if (!mc->mc_snum) {
*countp = 0;
return MDBX_NOTFOUND;
}
MDBX_page *mp = mc->mc_pg[mc->mc_top];
if ((mc->mc_flags & C_EOF) && mc->mc_ki[mc->mc_top] >= NUMKEYS(mp)) {
*countp = 0;
return MDBX_NOTFOUND;
}
*countp = 1;
if (mc->mc_xcursor != NULL) {
MDBX_node *leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
mdbx_cassert(mc, mc->mc_xcursor && (mc->mc_xcursor->mx_cursor.mc_flags &
C_INITIALIZED));
*countp = unlikely(mc->mc_xcursor->mx_db.md_entries > SIZE_MAX)
? SIZE_MAX
: (size_t)mc->mc_xcursor->mx_db.md_entries;
}
}
return MDBX_SUCCESS;
}
void mdbx_cursor_close(MDBX_cursor *mc) {
if (mc) {
mdbx_ensure(NULL, mc->mc_signature == MDBX_MC_SIGNATURE ||
mc->mc_signature == MDBX_MC_READY4CLOSE);
if (!mc->mc_backup) {
/* Remove from txn, if tracked.
* A read-only txn (!C_UNTRACK) may have been freed already,
* so do not peek inside it. Only write txns track cursors. */
if ((mc->mc_flags & C_UNTRACK) && mc->mc_txn->mt_cursors) {
MDBX_cursor **prev = &mc->mc_txn->mt_cursors[mc->mc_dbi];
while (*prev && *prev != mc)
prev = &(*prev)->mc_next;
if (*prev == mc)
*prev = mc->mc_next;
}
mc->mc_signature = 0;
mdbx_free(mc);
} else {
/* cursor closed before nested txn ends */
mdbx_cassert(mc, mc->mc_signature == MDBX_MC_SIGNATURE);
mc->mc_signature = MDBX_MC_WAIT4EOT;
}
}
}
MDBX_txn *mdbx_cursor_txn(MDBX_cursor *mc) {
if (unlikely(!mc || mc->mc_signature != MDBX_MC_SIGNATURE))
return NULL;
MDBX_txn *txn = mc->mc_txn;
if (unlikely(!txn || txn->mt_signature != MDBX_MT_SIGNATURE))
return NULL;
if (unlikely(txn->mt_flags & MDBX_TXN_FINISHED))
return NULL;
return txn;
}
MDBX_dbi mdbx_cursor_dbi(MDBX_cursor *mc) {
if (unlikely(!mc || mc->mc_signature != MDBX_MC_SIGNATURE))
return UINT_MAX;
return mc->mc_dbi;
}
/* Replace the key for a branch node with a new key.
* Set MDBX_TXN_ERROR on failure.
* [in] mc Cursor pointing to the node to operate on.
* [in] key The new key to use.
* Returns 0 on success, non-zero on failure. */
static int mdbx_update_key(MDBX_cursor *mc, const MDBX_val *key) {
MDBX_page *mp;
MDBX_node *node;
char *base;
size_t len;
int delta, ksize, oksize;
indx_t ptr, i, numkeys, indx;
DKBUF;
indx = mc->mc_ki[mc->mc_top];
mp = mc->mc_pg[mc->mc_top];
node = NODEPTR(mp, indx);
ptr = mp->mp_ptrs[indx];
if (MDBX_DEBUG) {
MDBX_val k2;
char kbuf2[DKBUF_MAXKEYSIZE * 2 + 1];
k2.iov_base = NODEKEY(node);
k2.iov_len = node->mn_ksize;
mdbx_debug("update key %u (ofs %u) [%s] to [%s] on page %" PRIaPGNO, indx,
ptr, mdbx_dkey(&k2, kbuf2, sizeof(kbuf2)), DKEY(key),
mp->mp_pgno);
}
/* Sizes must be 2-byte aligned. */
ksize = EVEN(key->iov_len);
oksize = EVEN(node->mn_ksize);
delta = ksize - oksize;
/* Shift node contents if EVEN(key length) changed. */
if (delta) {
if (SIZELEFT(mp) < delta) {
/* not enough space left, do a delete and split */
mdbx_debug("Not enough room, delta = %d, splitting...", delta);
pgno_t pgno = NODEPGNO(node);
mdbx_node_del(mc, 0);
int rc = mdbx_page_split(mc, key, NULL, pgno, MDBX_SPLIT_REPLACE);
if (rc == MDBX_SUCCESS && mdbx_audit_enabled())
rc = mdbx_cursor_check(mc, true);
return rc;
}
numkeys = NUMKEYS(mp);
for (i = 0; i < numkeys; i++) {
if (mp->mp_ptrs[i] <= ptr) {
mdbx_cassert(mc, mp->mp_ptrs[i] >= delta);
mp->mp_ptrs[i] -= (indx_t)delta;
}
}
base = (char *)mp + mp->mp_upper + PAGEHDRSZ;
len = ptr - mp->mp_upper + NODESIZE;
memmove(base - delta, base, len);
mdbx_cassert(mc, mp->mp_upper >= delta);
mp->mp_upper -= (indx_t)delta;
node = NODEPTR(mp, indx);
}
/* But even if no shift was needed, update ksize */
if (node->mn_ksize != key->iov_len)
node->mn_ksize = (uint16_t)key->iov_len;
memcpy(NODEKEY(node), key->iov_base, key->iov_len);
return MDBX_SUCCESS;
}
static void mdbx_cursor_copy(const MDBX_cursor *csrc, MDBX_cursor *cdst);
/* Move a node from csrc to cdst. */
static int mdbx_node_move(MDBX_cursor *csrc, MDBX_cursor *cdst, int fromleft) {
int rc;
DKBUF;
/* Mark src and dst as dirty. */
if (unlikely((rc = mdbx_page_touch(csrc)) || (rc = mdbx_page_touch(cdst))))
return rc;
MDBX_page *const psrc = csrc->mc_pg[csrc->mc_top];
MDBX_page *const pdst = cdst->mc_pg[cdst->mc_top];
mdbx_cassert(csrc, PAGETYPE(psrc) == PAGETYPE(pdst));
mdbx_cassert(csrc, csrc->mc_dbi == cdst->mc_dbi);
mdbx_cassert(csrc, csrc->mc_top == cdst->mc_top);
if (unlikely(PAGETYPE(psrc) != PAGETYPE(pdst))) {
bailout:
csrc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
return MDBX_PROBLEM;
}
MDBX_val key4move;
switch (PAGETYPE(psrc)) {
case P_BRANCH: {
const MDBX_node *srcnode = NODEPTR(psrc, csrc->mc_ki[csrc->mc_top]);
mdbx_cassert(csrc, srcnode->mn_flags == 0);
const pgno_t srcpg = NODEPGNO(srcnode);
key4move.iov_len = NODEKSZ(srcnode);
key4move.iov_base = NODEKEY(srcnode);
if (csrc->mc_ki[csrc->mc_top] == 0) {
const uint16_t snum = csrc->mc_snum;
mdbx_cassert(csrc, snum > 0);
/* must find the lowest key below src */
rc = mdbx_page_search_lowest(csrc);
MDBX_page *psrc2 = csrc->mc_pg[csrc->mc_top];
if (unlikely(rc))
return rc;
mdbx_cassert(csrc, IS_LEAF(psrc2));
if (unlikely(!IS_LEAF(psrc2)))
goto bailout;
if (IS_LEAF2(psrc2)) {
key4move.iov_len = csrc->mc_db->md_xsize;
key4move.iov_base = LEAF2KEY(psrc2, 0, key4move.iov_len);
} else {
const MDBX_node *s2 = NODEPTR(psrc2, 0);
key4move.iov_len = NODEKSZ(s2);
key4move.iov_base = NODEKEY(s2);
}
csrc->mc_snum = snum;
csrc->mc_top = snum - 1;
csrc->mc_ki[csrc->mc_top] = 0;
/* paranoia */
mdbx_cassert(csrc, psrc == csrc->mc_pg[csrc->mc_top]);
mdbx_cassert(csrc, IS_BRANCH(psrc));
if (unlikely(!IS_BRANCH(psrc)))
goto bailout;
}
if (cdst->mc_ki[cdst->mc_top] == 0) {
const uint16_t snum = cdst->mc_snum;
mdbx_cassert(csrc, snum > 0);
MDBX_cursor mn;
mdbx_cursor_copy(cdst, &mn);
mn.mc_xcursor = NULL;
/* must find the lowest key below dst */
rc = mdbx_page_search_lowest(&mn);
if (unlikely(rc))
return rc;
MDBX_page *const pdst2 = mn.mc_pg[mn.mc_top];
mdbx_cassert(cdst, IS_LEAF(pdst2));
if (unlikely(!IS_LEAF(pdst2)))
goto bailout;
MDBX_val key;
if (IS_LEAF2(pdst2)) {
key.iov_len = mn.mc_db->md_xsize;
key.iov_base = LEAF2KEY(pdst2, 0, key.iov_len);
} else {
MDBX_node *s2 = NODEPTR(pdst2, 0);
key.iov_len = NODEKSZ(s2);
key.iov_base = NODEKEY(s2);
}
mn.mc_snum = snum;
mn.mc_top = snum - 1;
mn.mc_ki[mn.mc_top] = 0;
rc = mdbx_update_key(&mn, &key);
if (unlikely(rc))
return rc;
}
mdbx_debug("moving %s-node %u [%s] on page %" PRIaPGNO
" to node %u on page %" PRIaPGNO,
"branch", csrc->mc_ki[csrc->mc_top], DKEY(&key4move),
psrc->mp_pgno, cdst->mc_ki[cdst->mc_top], pdst->mp_pgno);
/* Add the node to the destination page. */
rc =
mdbx_node_add_branch(cdst, cdst->mc_ki[cdst->mc_top], &key4move, srcpg);
} break;
case P_LEAF: {
const MDBX_node *srcnode = NODEPTR(psrc, csrc->mc_ki[csrc->mc_top]);
MDBX_val data;
data.iov_len = NODEDSZ(srcnode);
data.iov_base = NODEDATA(srcnode);
key4move.iov_len = NODEKSZ(srcnode);
key4move.iov_base = NODEKEY(srcnode);
mdbx_debug("moving %s-node %u [%s] on page %" PRIaPGNO
" to node %u on page %" PRIaPGNO,
"leaf", csrc->mc_ki[csrc->mc_top], DKEY(&key4move),
psrc->mp_pgno, cdst->mc_ki[cdst->mc_top], pdst->mp_pgno);
/* Add the node to the destination page. */
rc = mdbx_node_add_leaf(cdst, cdst->mc_ki[cdst->mc_top], &key4move, &data,
srcnode->mn_flags);
} break;
case P_LEAF | P_LEAF2: {
key4move.iov_len = csrc->mc_db->md_xsize;
key4move.iov_base =
LEAF2KEY(psrc, csrc->mc_ki[csrc->mc_top], key4move.iov_len);
mdbx_debug("moving %s-node %u [%s] on page %" PRIaPGNO
" to node %u on page %" PRIaPGNO,
"leaf2", csrc->mc_ki[csrc->mc_top], DKEY(&key4move),
psrc->mp_pgno, cdst->mc_ki[cdst->mc_top], pdst->mp_pgno);
/* Add the node to the destination page. */
rc = mdbx_node_add_leaf2(cdst, cdst->mc_ki[cdst->mc_top], &key4move);
} break;
default:
goto bailout;
}
if (unlikely(rc != MDBX_SUCCESS))
return rc;
/* Delete the node from the source page. */
mdbx_node_del(csrc, key4move.iov_len);
mdbx_cassert(csrc, psrc == csrc->mc_pg[csrc->mc_top]);
mdbx_cassert(cdst, pdst == cdst->mc_pg[cdst->mc_top]);
mdbx_cassert(csrc, PAGETYPE(psrc) == PAGETYPE(pdst));
{
/* Adjust other cursors pointing to mp */
MDBX_cursor *m2, *m3;
const MDBX_dbi dbi = csrc->mc_dbi;
mdbx_cassert(csrc, csrc->mc_top == cdst->mc_top);
if (fromleft) {
/* If we're adding on the left, bump others up */
for (m2 = csrc->mc_txn->mt_cursors[dbi]; m2; m2 = m2->mc_next) {
m3 = (csrc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
if (!(m3->mc_flags & C_INITIALIZED) || m3->mc_top < csrc->mc_top)
continue;
if (m3 != cdst && m3->mc_pg[csrc->mc_top] == pdst &&
m3->mc_ki[csrc->mc_top] >= cdst->mc_ki[csrc->mc_top]) {
m3->mc_ki[csrc->mc_top]++;
}
if (m3 != csrc && m3->mc_pg[csrc->mc_top] == psrc &&
m3->mc_ki[csrc->mc_top] == csrc->mc_ki[csrc->mc_top]) {
m3->mc_pg[csrc->mc_top] = pdst;
m3->mc_ki[csrc->mc_top] = cdst->mc_ki[cdst->mc_top];
mdbx_cassert(csrc, csrc->mc_top > 0);
m3->mc_ki[csrc->mc_top - 1]++;
}
if (XCURSOR_INITED(m3) && IS_LEAF(psrc))
XCURSOR_REFRESH(m3, m3->mc_pg[csrc->mc_top], m3->mc_ki[csrc->mc_top]);
}
} else {
/* Adding on the right, bump others down */
for (m2 = csrc->mc_txn->mt_cursors[dbi]; m2; m2 = m2->mc_next) {
m3 = (csrc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
if (m3 == csrc)
continue;
if (!(m3->mc_flags & C_INITIALIZED) || m3->mc_top < csrc->mc_top)
continue;
if (m3->mc_pg[csrc->mc_top] == psrc) {
if (!m3->mc_ki[csrc->mc_top]) {
m3->mc_pg[csrc->mc_top] = pdst;
m3->mc_ki[csrc->mc_top] = cdst->mc_ki[cdst->mc_top];
mdbx_cassert(csrc, csrc->mc_top > 0);
m3->mc_ki[csrc->mc_top - 1]--;
} else {
m3->mc_ki[csrc->mc_top]--;
}
if (XCURSOR_INITED(m3) && IS_LEAF(psrc))
XCURSOR_REFRESH(m3, m3->mc_pg[csrc->mc_top],
m3->mc_ki[csrc->mc_top]);
}
}
}
}
/* Update the parent separators. */
if (csrc->mc_ki[csrc->mc_top] == 0) {
mdbx_cassert(csrc, csrc->mc_top > 0);
if (csrc->mc_ki[csrc->mc_top - 1] != 0) {
MDBX_val key;
if (IS_LEAF2(psrc)) {
key.iov_len = psrc->mp_leaf2_ksize;
key.iov_base = LEAF2KEY(psrc, 0, key.iov_len);
} else {
MDBX_node *srcnode = NODEPTR(psrc, 0);
key.iov_len = NODEKSZ(srcnode);
key.iov_base = NODEKEY(srcnode);
}
mdbx_debug("update separator for source page %" PRIaPGNO " to [%s]",
psrc->mp_pgno, DKEY(&key));
MDBX_cursor mn;
mdbx_cursor_copy(csrc, &mn);
mn.mc_xcursor = NULL;
mdbx_cassert(csrc, mn.mc_snum > 0);
mn.mc_snum--;
mn.mc_top--;
/* We want mdbx_rebalance to find mn when doing fixups */
WITH_CURSOR_TRACKING(mn, rc = mdbx_update_key(&mn, &key));
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
if (IS_BRANCH(psrc)) {
const MDBX_val nullkey = {0, 0};
const indx_t ix = csrc->mc_ki[csrc->mc_top];
csrc->mc_ki[csrc->mc_top] = 0;
rc = mdbx_update_key(csrc, &nullkey);
csrc->mc_ki[csrc->mc_top] = ix;
mdbx_cassert(csrc, rc == MDBX_SUCCESS);
}
}
if (cdst->mc_ki[cdst->mc_top] == 0) {
mdbx_cassert(cdst, cdst->mc_top > 0);
if (cdst->mc_ki[cdst->mc_top - 1] != 0) {
MDBX_val key;
if (IS_LEAF2(pdst)) {
key.iov_len = pdst->mp_leaf2_ksize;
key.iov_base = LEAF2KEY(pdst, 0, key.iov_len);
} else {
MDBX_node *srcnode = NODEPTR(pdst, 0);
key.iov_len = NODEKSZ(srcnode);
key.iov_base = NODEKEY(srcnode);
}
mdbx_debug("update separator for destination page %" PRIaPGNO " to [%s]",
pdst->mp_pgno, DKEY(&key));
MDBX_cursor mn;
mdbx_cursor_copy(cdst, &mn);
mn.mc_xcursor = NULL;
mdbx_cassert(cdst, mn.mc_snum > 0);
mn.mc_snum--;
mn.mc_top--;
/* We want mdbx_rebalance to find mn when doing fixups */
WITH_CURSOR_TRACKING(mn, rc = mdbx_update_key(&mn, &key));
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
if (IS_BRANCH(pdst)) {
const MDBX_val nullkey = {0, 0};
const indx_t ix = cdst->mc_ki[cdst->mc_top];
cdst->mc_ki[cdst->mc_top] = 0;
rc = mdbx_update_key(cdst, &nullkey);
cdst->mc_ki[cdst->mc_top] = ix;
mdbx_cassert(cdst, rc == MDBX_SUCCESS);
}
}
return MDBX_SUCCESS;
}
/* Merge one page into another.
*
* The nodes from the page pointed to by csrc will be copied to the page
* pointed to by cdst and then the csrc page will be freed.
*
* [in] csrc Cursor pointing to the source page.
* [in] cdst Cursor pointing to the destination page.
*
* Returns 0 on success, non-zero on failure. */
static int mdbx_page_merge(MDBX_cursor *csrc, MDBX_cursor *cdst) {
MDBX_node *srcnode;
MDBX_val key;
int rc;
mdbx_cassert(csrc, csrc != cdst);
/* Mark dst as dirty. */
if (unlikely(rc = mdbx_page_touch(cdst)))
return rc;
MDBX_page *const psrc = csrc->mc_pg[csrc->mc_top];
MDBX_page *const pdst = cdst->mc_pg[cdst->mc_top];
mdbx_debug("merging page %" PRIaPGNO " into %" PRIaPGNO, psrc->mp_pgno,
pdst->mp_pgno);
mdbx_cassert(csrc, PAGETYPE(psrc) == PAGETYPE(pdst));
mdbx_cassert(csrc,
csrc->mc_dbi == cdst->mc_dbi && csrc->mc_db == cdst->mc_db);
mdbx_cassert(csrc, csrc->mc_snum > 1); /* can't merge root page */
mdbx_cassert(cdst, cdst->mc_snum > 1);
mdbx_cassert(cdst, cdst->mc_snum < cdst->mc_db->md_depth ||
IS_LEAF(cdst->mc_pg[cdst->mc_db->md_depth - 1]));
mdbx_cassert(csrc, csrc->mc_snum < csrc->mc_db->md_depth ||
IS_LEAF(csrc->mc_pg[csrc->mc_db->md_depth - 1]));
const int pagetype = PAGETYPE(psrc);
/* Move all nodes from src to dst */
const unsigned nkeys = NUMKEYS(pdst);
unsigned j = nkeys;
if (unlikely(pagetype & P_LEAF2)) {
key.iov_len = csrc->mc_db->md_xsize;
key.iov_base = PAGEDATA(psrc);
for (unsigned i = 0; i < NUMKEYS(psrc); i++, j++) {
rc = mdbx_node_add_leaf2(cdst, j, &key);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
key.iov_base = (char *)key.iov_base + key.iov_len;
}
} else {
for (unsigned i = 0; i < NUMKEYS(psrc); i++, j++) {
srcnode = NODEPTR(psrc, i);
if (i == 0 && (pagetype & P_BRANCH)) {
MDBX_cursor mn;
mdbx_cursor_copy(csrc, &mn);
mn.mc_xcursor = NULL;
/* must find the lowest key below src */
rc = mdbx_page_search_lowest(&mn);
if (unlikely(rc))
return rc;
if (IS_LEAF2(mn.mc_pg[mn.mc_top])) {
key.iov_len = mn.mc_db->md_xsize;
key.iov_base = LEAF2KEY(mn.mc_pg[mn.mc_top], 0, key.iov_len);
} else {
MDBX_node *s2 = NODEPTR(mn.mc_pg[mn.mc_top], 0);
key.iov_len = NODEKSZ(s2);
key.iov_base = NODEKEY(s2);
}
} else {
key.iov_len = srcnode->mn_ksize;
key.iov_base = NODEKEY(srcnode);
}
if (pagetype & P_LEAF) {
MDBX_val data;
data.iov_len = NODEDSZ(srcnode);
data.iov_base = NODEDATA(srcnode);
rc = mdbx_node_add_leaf(cdst, j, &key, &data, srcnode->mn_flags);
} else {
mdbx_cassert(csrc, srcnode->mn_flags == 0);
rc = mdbx_node_add_branch(cdst, j, &key, NODEPGNO(srcnode));
}
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
}
mdbx_debug("dst page %" PRIaPGNO " now has %u keys (%.1f%% filled)",
pdst->mp_pgno, NUMKEYS(pdst),
PAGEFILL(cdst->mc_txn->mt_env, pdst) / 10.24);
mdbx_cassert(csrc, psrc == csrc->mc_pg[csrc->mc_top]);
mdbx_cassert(cdst, pdst == cdst->mc_pg[cdst->mc_top]);
/* Unlink the src page from parent and add to free list. */
csrc->mc_top--;
mdbx_node_del(csrc, 0);
if (csrc->mc_ki[csrc->mc_top] == 0) {
const MDBX_val nullkey = {0, 0};
rc = mdbx_update_key(csrc, &nullkey);
if (unlikely(rc)) {
csrc->mc_top++;
return rc;
}
}
csrc->mc_top++;
mdbx_cassert(csrc, psrc == csrc->mc_pg[csrc->mc_top]);
mdbx_cassert(cdst, pdst == cdst->mc_pg[cdst->mc_top]);
{
/* Adjust other cursors pointing to mp */
MDBX_cursor *m2, *m3;
const MDBX_dbi dbi = csrc->mc_dbi;
const unsigned top = csrc->mc_top;
for (m2 = csrc->mc_txn->mt_cursors[dbi]; m2; m2 = m2->mc_next) {
m3 = (csrc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
if (m3 == csrc || top >= m3->mc_snum)
continue;
if (m3->mc_pg[top] == psrc) {
m3->mc_pg[top] = pdst;
mdbx_cassert(m3, nkeys + m3->mc_ki[top] <= UINT16_MAX);
m3->mc_ki[top] += (indx_t)nkeys;
m3->mc_ki[top - 1] = cdst->mc_ki[top - 1];
} else if (m3->mc_pg[top - 1] == csrc->mc_pg[top - 1] &&
m3->mc_ki[top - 1] > csrc->mc_ki[top - 1]) {
m3->mc_ki[top - 1]--;
}
if (XCURSOR_INITED(m3) && IS_LEAF(psrc))
XCURSOR_REFRESH(m3, m3->mc_pg[top], m3->mc_ki[top]);
}
}
/* If not operating on FreeDB, allow this page to be reused
* in this txn. Otherwise just add to free list. */
rc = mdbx_page_loose(csrc, psrc);
if (unlikely(rc))
return rc;
mdbx_cassert(cdst, cdst->mc_db->md_entries > 0);
mdbx_cassert(cdst, cdst->mc_snum <= cdst->mc_db->md_depth);
mdbx_cassert(cdst, cdst->mc_top > 0);
mdbx_cassert(cdst, cdst->mc_snum == cdst->mc_top + 1);
MDBX_page *const top_page = cdst->mc_pg[cdst->mc_top];
const indx_t top_indx = cdst->mc_ki[cdst->mc_top];
const uint16_t save_snum = cdst->mc_snum;
const uint16_t save_depth = cdst->mc_db->md_depth;
mdbx_cursor_pop(cdst);
rc = mdbx_rebalance(cdst);
if (unlikely(rc))
return rc;
mdbx_cassert(cdst, cdst->mc_db->md_entries > 0);
mdbx_cassert(cdst, cdst->mc_snum <= cdst->mc_db->md_depth);
mdbx_cassert(cdst, cdst->mc_snum == cdst->mc_top + 1);
if (IS_LEAF(cdst->mc_pg[cdst->mc_top])) {
/* LY: don't touch cursor if top-page is a LEAF */
mdbx_cassert(cdst, IS_LEAF(cdst->mc_pg[cdst->mc_top]) ||
PAGETYPE(cdst->mc_pg[cdst->mc_top]) == pagetype);
return MDBX_SUCCESS;
}
if (pagetype != PAGETYPE(top_page)) {
/* LY: LEAF-page becomes BRANCH, unable restore cursor's stack */
goto bailout;
}
if (top_page == cdst->mc_pg[cdst->mc_top]) {
/* LY: don't touch cursor if prev top-page already on the top */
mdbx_cassert(cdst, cdst->mc_ki[cdst->mc_top] == top_indx);
mdbx_cassert(cdst, IS_LEAF(cdst->mc_pg[cdst->mc_top]) ||
PAGETYPE(cdst->mc_pg[cdst->mc_top]) == pagetype);
return MDBX_SUCCESS;
}
const int new_snum = save_snum - save_depth + cdst->mc_db->md_depth;
if (unlikely(new_snum < 1 || new_snum > cdst->mc_db->md_depth)) {
/* LY: out of range, unable restore cursor's stack */
goto bailout;
}
if (top_page == cdst->mc_pg[new_snum - 1]) {
mdbx_cassert(cdst, cdst->mc_ki[new_snum - 1] == top_indx);
/* LY: restore cursor stack */
cdst->mc_snum = (uint16_t)new_snum;
cdst->mc_top = (uint16_t)new_snum - 1;
mdbx_cassert(cdst, cdst->mc_snum < cdst->mc_db->md_depth ||
IS_LEAF(cdst->mc_pg[cdst->mc_db->md_depth - 1]));
mdbx_cassert(cdst, IS_LEAF(cdst->mc_pg[cdst->mc_top]) ||
PAGETYPE(cdst->mc_pg[cdst->mc_top]) == pagetype);
return MDBX_SUCCESS;
}
MDBX_page *const stub_page = (MDBX_page *)(~(uintptr_t)top_page);
const indx_t stub_indx = top_indx;
if (save_depth > cdst->mc_db->md_depth &&
((cdst->mc_pg[save_snum - 1] == top_page &&
cdst->mc_ki[save_snum - 1] == top_indx) ||
(cdst->mc_pg[save_snum - 1] == stub_page &&
cdst->mc_ki[save_snum - 1] == stub_indx))) {
/* LY: restore cursor stack */
cdst->mc_pg[new_snum - 1] = top_page;
cdst->mc_ki[new_snum - 1] = top_indx;
cdst->mc_pg[new_snum] = (MDBX_page *)(~(uintptr_t)cdst->mc_pg[new_snum]);
cdst->mc_ki[new_snum] = ~cdst->mc_ki[new_snum];
cdst->mc_snum = (uint16_t)new_snum;
cdst->mc_top = (uint16_t)new_snum - 1;
mdbx_cassert(cdst, cdst->mc_snum < cdst->mc_db->md_depth ||
IS_LEAF(cdst->mc_pg[cdst->mc_db->md_depth - 1]));
mdbx_cassert(cdst, IS_LEAF(cdst->mc_pg[cdst->mc_top]) ||
PAGETYPE(cdst->mc_pg[cdst->mc_top]) == pagetype);
return MDBX_SUCCESS;
}
bailout:
/* LY: unable restore cursor's stack */
cdst->mc_flags &= ~C_INITIALIZED;
return MDBX_CURSOR_FULL;
}
/* Copy the contents of a cursor.
* [in] csrc The cursor to copy from.
* [out] cdst The cursor to copy to. */
static void mdbx_cursor_copy(const MDBX_cursor *csrc, MDBX_cursor *cdst) {
unsigned i;
mdbx_cassert(csrc,
csrc->mc_txn->mt_txnid >= *csrc->mc_txn->mt_env->me_oldest);
cdst->mc_txn = csrc->mc_txn;
cdst->mc_dbi = csrc->mc_dbi;
cdst->mc_db = csrc->mc_db;
cdst->mc_dbx = csrc->mc_dbx;
cdst->mc_snum = csrc->mc_snum;
cdst->mc_top = csrc->mc_top;
cdst->mc_flags = csrc->mc_flags;
for (i = 0; i < csrc->mc_snum; i++) {
cdst->mc_pg[i] = csrc->mc_pg[i];
cdst->mc_ki[i] = csrc->mc_ki[i];
}
}
/* Rebalance the tree after a delete operation.
* [in] mc Cursor pointing to the page where rebalancing should begin.
* Returns 0 on success, non-zero on failure. */
static int mdbx_rebalance(MDBX_cursor *mc) {
MDBX_node *node;
int rc;
unsigned minkeys, thresh;
mdbx_cassert(mc, mc->mc_snum > 0);
mdbx_cassert(mc, mc->mc_snum < mc->mc_db->md_depth ||
IS_LEAF(mc->mc_pg[mc->mc_db->md_depth - 1]));
const int pagetype = PAGETYPE(mc->mc_pg[mc->mc_top]);
if (pagetype == P_BRANCH) {
minkeys = 2;
thresh = 1;
} else {
minkeys = 1;
thresh = FILL_THRESHOLD;
}
mdbx_debug("rebalancing %s page %" PRIaPGNO " (has %u keys, %.1f%% full)",
(pagetype & P_LEAF) ? "leaf" : "branch",
mc->mc_pg[mc->mc_top]->mp_pgno, NUMKEYS(mc->mc_pg[mc->mc_top]),
PAGEFILL(mc->mc_txn->mt_env, mc->mc_pg[mc->mc_top]) / 10.24);
if (PAGEFILL(mc->mc_txn->mt_env, mc->mc_pg[mc->mc_top]) >= thresh &&
NUMKEYS(mc->mc_pg[mc->mc_top]) >= minkeys) {
mdbx_debug("no need to rebalance page %" PRIaPGNO ", above fill threshold",
mc->mc_pg[mc->mc_top]->mp_pgno);
mdbx_cassert(mc, mc->mc_db->md_entries > 0);
return MDBX_SUCCESS;
}
if (mc->mc_snum < 2) {
MDBX_page *const mp = mc->mc_pg[0];
const unsigned nkeys = NUMKEYS(mp);
mdbx_cassert(mc, (mc->mc_db->md_entries == 0) == (nkeys == 0));
if (IS_SUBP(mp)) {
mdbx_debug("Can't rebalance a subpage, ignoring");
mdbx_cassert(mc, pagetype & P_LEAF);
return MDBX_SUCCESS;
}
if (nkeys == 0) {
mdbx_cassert(mc, IS_LEAF(mp));
mdbx_debug("tree is completely empty");
mc->mc_db->md_root = P_INVALID;
mc->mc_db->md_depth = 0;
mdbx_cassert(mc, mc->mc_db->md_branch_pages == 0 &&
mc->mc_db->md_overflow_pages == 0 &&
mc->mc_db->md_leaf_pages == 1);
mc->mc_db->md_leaf_pages = 0;
if (mc->mc_flags & C_SUB)
mdbx_outer_db(mc)->md_leaf_pages -= 1;
rc = mdbx_pnl_append(&mc->mc_txn->mt_befree_pages, mp->mp_pgno);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
/* Adjust cursors pointing to mp */
const MDBX_dbi dbi = mc->mc_dbi;
for (MDBX_cursor *m2 = mc->mc_txn->mt_cursors[dbi]; m2;
m2 = m2->mc_next) {
MDBX_cursor *m3 =
(mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
if (m3 == mc || !(m3->mc_flags & C_INITIALIZED))
continue;
if (m3->mc_pg[0] == mp) {
m3->mc_snum = 0;
m3->mc_top = 0;
m3->mc_flags &= ~C_INITIALIZED;
}
}
mc->mc_snum = 0;
mc->mc_top = 0;
mc->mc_flags &= ~C_INITIALIZED;
} else if (IS_BRANCH(mp) && nkeys == 1) {
mdbx_debug("collapsing root page!");
rc = mdbx_pnl_append(&mc->mc_txn->mt_befree_pages, mp->mp_pgno);
if (unlikely(rc))
return rc;
mc->mc_db->md_root = NODEPGNO(NODEPTR(mp, 0));
rc = mdbx_page_get(mc, mc->mc_db->md_root, &mc->mc_pg[0], NULL);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
mc->mc_db->md_depth--;
mc->mc_db->md_branch_pages--;
if (mc->mc_flags & C_SUB)
mdbx_outer_db(mc)->md_branch_pages -= 1;
mc->mc_ki[0] = mc->mc_ki[1];
for (int i = 1; i < mc->mc_db->md_depth; i++) {
mc->mc_pg[i] = mc->mc_pg[i + 1];
mc->mc_ki[i] = mc->mc_ki[i + 1];
}
/* Adjust other cursors pointing to mp */
MDBX_cursor *m2, *m3;
MDBX_dbi dbi = mc->mc_dbi;
for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2 = m2->mc_next) {
m3 = (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
if (m3 == mc || !(m3->mc_flags & C_INITIALIZED))
continue;
if (m3->mc_pg[0] == mp) {
for (int i = 0; i < mc->mc_db->md_depth; i++) {
m3->mc_pg[i] = m3->mc_pg[i + 1];
m3->mc_ki[i] = m3->mc_ki[i + 1];
}
m3->mc_snum--;
m3->mc_top--;
}
}
mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]) ||
PAGETYPE(mc->mc_pg[mc->mc_top]) == pagetype);
mdbx_cassert(mc, mc->mc_snum < mc->mc_db->md_depth ||
IS_LEAF(mc->mc_pg[mc->mc_db->md_depth - 1]));
} else {
mdbx_debug("root page %" PRIaPGNO
" doesn't need rebalancing (flags 0x%x)",
mp->mp_pgno, mp->mp_flags);
}
return MDBX_SUCCESS;
}
/* The parent (branch page) must have at least 2 pointers,
* otherwise the tree is invalid. */
const unsigned pre_top = mc->mc_top - 1;
mdbx_cassert(mc, IS_BRANCH(mc->mc_pg[pre_top]));
mdbx_cassert(mc, !IS_SUBP(mc->mc_pg[0]));
mdbx_cassert(mc, NUMKEYS(mc->mc_pg[pre_top]) > 1);
/* Leaf page fill factor is below the threshold.
* Try to move keys from left or right neighbor, or
* merge with a neighbor page. */
/* Find neighbors. */
MDBX_cursor mn;
mdbx_cursor_copy(mc, &mn);
mn.mc_xcursor = NULL;
indx_t oldki = mc->mc_ki[mc->mc_top];
bool fromleft;
if (mc->mc_ki[pre_top] == 0) {
/* We're the leftmost leaf in our parent. */
mdbx_debug("reading right neighbor");
mn.mc_ki[pre_top]++;
node = NODEPTR(mc->mc_pg[pre_top], mn.mc_ki[pre_top]);
rc = mdbx_page_get(mc, NODEPGNO(node), &mn.mc_pg[mn.mc_top], NULL);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
mdbx_cassert(mc, PAGETYPE(mn.mc_pg[mn.mc_top]) ==
PAGETYPE(mc->mc_pg[mc->mc_top]));
mn.mc_ki[mn.mc_top] = 0;
mc->mc_ki[mc->mc_top] = NUMKEYS(mc->mc_pg[mc->mc_top]);
fromleft = false;
} else {
/* There is at least one neighbor to the left. */
mdbx_debug("reading left neighbor");
mn.mc_ki[pre_top]--;
node = NODEPTR(mc->mc_pg[pre_top], mn.mc_ki[pre_top]);
rc = mdbx_page_get(mc, NODEPGNO(node), &mn.mc_pg[mn.mc_top], NULL);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
mdbx_cassert(mc, PAGETYPE(mn.mc_pg[mn.mc_top]) ==
PAGETYPE(mc->mc_pg[mc->mc_top]));
mn.mc_ki[mn.mc_top] = NUMKEYS(mn.mc_pg[mn.mc_top]) - 1;
mc->mc_ki[mc->mc_top] = 0;
fromleft = true;
}
mdbx_debug("found neighbor page %" PRIaPGNO " (%u keys, %.1f%% full)",
mn.mc_pg[mn.mc_top]->mp_pgno, NUMKEYS(mn.mc_pg[mn.mc_top]),
PAGEFILL(mc->mc_txn->mt_env, mn.mc_pg[mn.mc_top]) / 10.24);
/* If the neighbor page is above threshold and has enough keys,
* move one key from it. Otherwise we should try to merge them.
* (A branch page must never have less than 2 keys.) */
if (PAGEFILL(mc->mc_txn->mt_env, mn.mc_pg[mn.mc_top]) >= thresh &&
NUMKEYS(mn.mc_pg[mn.mc_top]) > minkeys) {
rc = mdbx_node_move(&mn, mc, fromleft);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
oldki += fromleft /* if we inserted on left, bump position up */;
mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]) ||
PAGETYPE(mc->mc_pg[mc->mc_top]) == pagetype);
mdbx_cassert(mc, mc->mc_snum < mc->mc_db->md_depth ||
IS_LEAF(mc->mc_pg[mc->mc_db->md_depth - 1]));
} else {
if (!fromleft) {
rc = mdbx_page_merge(&mn, mc);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]) ||
PAGETYPE(mc->mc_pg[mc->mc_top]) == pagetype);
mdbx_cassert(mc, mc->mc_snum < mc->mc_db->md_depth ||
IS_LEAF(mc->mc_pg[mc->mc_db->md_depth - 1]));
} else {
oldki += NUMKEYS(mn.mc_pg[mn.mc_top]);
mn.mc_ki[mn.mc_top] += mc->mc_ki[mn.mc_top] + 1;
/* We want mdbx_rebalance to find mn when doing fixups */
WITH_CURSOR_TRACKING(mn, rc = mdbx_page_merge(mc, &mn));
if (unlikely(rc != MDBX_SUCCESS))
return rc;
mdbx_cursor_copy(&mn, mc);
mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]) ||
PAGETYPE(mc->mc_pg[mc->mc_top]) == pagetype);
mdbx_cassert(mc, mc->mc_snum < mc->mc_db->md_depth ||
IS_LEAF(mc->mc_pg[mc->mc_db->md_depth - 1]));
}
mc->mc_flags &= ~C_EOF;
}
mc->mc_ki[mc->mc_top] = oldki;
return MDBX_SUCCESS;
}
static __cold int mdbx_cursor_check(MDBX_cursor *mc, bool pending) {
mdbx_cassert(mc, mc->mc_top == mc->mc_snum - 1);
if (unlikely(mc->mc_top != mc->mc_snum - 1))
return MDBX_CURSOR_FULL;
mdbx_cassert(mc, pending ? mc->mc_snum <= mc->mc_db->md_depth
: mc->mc_snum == mc->mc_db->md_depth);
if (unlikely(pending ? mc->mc_snum > mc->mc_db->md_depth
: mc->mc_snum != mc->mc_db->md_depth))
return MDBX_CURSOR_FULL;
for (int n = 0; n < mc->mc_snum; ++n) {
MDBX_page *mp = mc->mc_pg[n];
const unsigned numkeys = NUMKEYS(mp);
const bool expect_branch = (n < mc->mc_db->md_depth - 1) ? true : false;
const bool expect_nested_leaf =
(n + 1 == mc->mc_db->md_depth - 1) ? true : false;
const bool branch = IS_BRANCH(mp) ? true : false;
mdbx_cassert(mc, branch == expect_branch);
if (unlikely(branch != expect_branch))
return MDBX_CURSOR_FULL;
if (!pending) {
mdbx_cassert(mc, numkeys > mc->mc_ki[n] ||
(!branch && numkeys == mc->mc_ki[n] &&
(mc->mc_flags & C_EOF) != 0));
if (unlikely(numkeys <= mc->mc_ki[n] &&
!(!branch && numkeys == mc->mc_ki[n] &&
(mc->mc_flags & C_EOF) != 0)))
return MDBX_CURSOR_FULL;
} else {
mdbx_cassert(mc, numkeys + 1 >= mc->mc_ki[n]);
if (unlikely(numkeys + 1 < mc->mc_ki[n]))
return MDBX_CURSOR_FULL;
}
for (unsigned i = 0; i < numkeys; ++i) {
MDBX_node *node = NODEPTR(mp, i);
if (branch) {
mdbx_cassert(mc, node->mn_flags == 0);
if (unlikely(node->mn_flags != 0))
return MDBX_CURSOR_FULL;
pgno_t pgno = NODEPGNO(node);
MDBX_page *np;
int rc = mdbx_page_get(mc, pgno, &np, NULL);
mdbx_cassert(mc, rc == MDBX_SUCCESS);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
const bool nested_leaf = IS_LEAF(np) ? true : false;
mdbx_cassert(mc, nested_leaf == expect_nested_leaf);
if (unlikely(nested_leaf != expect_nested_leaf))
return MDBX_CURSOR_FULL;
}
}
}
return MDBX_SUCCESS;
}
/* Complete a delete operation started by mdbx_cursor_del(). */
static int mdbx_cursor_del0(MDBX_cursor *mc) {
int rc;
MDBX_page *mp;
indx_t ki;
unsigned nkeys;
MDBX_cursor *m2, *m3;
MDBX_dbi dbi = mc->mc_dbi;
mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]));
ki = mc->mc_ki[mc->mc_top];
mp = mc->mc_pg[mc->mc_top];
mdbx_node_del(mc, mc->mc_db->md_xsize);
mc->mc_db->md_entries--;
{
/* Adjust other cursors pointing to mp */
for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2 = m2->mc_next) {
m3 = (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
if (m3 == mc || !(m2->mc_flags & m3->mc_flags & C_INITIALIZED))
continue;
if (m3->mc_snum < mc->mc_snum)
continue;
if (m3->mc_pg[mc->mc_top] == mp) {
if (m3->mc_ki[mc->mc_top] == ki) {
m3->mc_flags |= C_DEL;
if (mc->mc_db->md_flags & MDBX_DUPSORT) {
/* Sub-cursor referred into dataset which is gone */
m3->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
}
continue;
} else if (m3->mc_ki[mc->mc_top] > ki) {
m3->mc_ki[mc->mc_top]--;
}
if (XCURSOR_INITED(m3))
XCURSOR_REFRESH(m3, m3->mc_pg[mc->mc_top], m3->mc_ki[mc->mc_top]);
}
}
}
rc = mdbx_rebalance(mc);
if (likely(rc == MDBX_SUCCESS)) {
/* DB is totally empty now, just bail out.
* Other cursors adjustments were already done
* by mdbx_rebalance and aren't needed here. */
if (!mc->mc_snum) {
mdbx_cassert(mc, mc->mc_db->md_entries == 0 && mc->mc_db->md_depth == 0 &&
mc->mc_db->md_root == P_INVALID);
mc->mc_flags |= C_DEL | C_EOF;
return rc;
}
ki = mc->mc_ki[mc->mc_top];
mp = mc->mc_pg[mc->mc_top];
mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]));
nkeys = NUMKEYS(mp);
mdbx_cassert(mc, (mc->mc_db->md_entries > 0 && nkeys > 0) ||
((mc->mc_flags & C_SUB) &&
mc->mc_db->md_entries == 0 && nkeys == 0));
/* Adjust THIS and other cursors pointing to mp */
for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2 = m2->mc_next) {
m3 = (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
if (m3 == mc || !(m2->mc_flags & m3->mc_flags & C_INITIALIZED))
continue;
if (m3->mc_snum < mc->mc_snum)
continue;
if (m3->mc_pg[mc->mc_top] == mp) {
/* if m3 points past last node in page, find next sibling */
if (m3->mc_ki[mc->mc_top] >= nkeys) {
rc = mdbx_cursor_sibling(m3, true);
if (rc == MDBX_NOTFOUND) {
m3->mc_flags |= C_EOF;
rc = MDBX_SUCCESS;
continue;
} else if (unlikely(rc != MDBX_SUCCESS))
break;
}
if (m3->mc_ki[mc->mc_top] >= ki || m3->mc_pg[mc->mc_top] != mp) {
if ((mc->mc_db->md_flags & MDBX_DUPSORT) != 0 &&
(m3->mc_flags & C_EOF) == 0) {
MDBX_node *node =
NODEPTR(m3->mc_pg[m3->mc_top], m3->mc_ki[m3->mc_top]);
/* If this node has dupdata, it may need to be reinited
* because its data has moved.
* If the xcursor was not initd it must be reinited.
* Else if node points to a subDB, nothing is needed. */
if (node->mn_flags & F_DUPDATA) {
if (m3->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) {
if (!(node->mn_flags & F_SUBDATA))
m3->mc_xcursor->mx_cursor.mc_pg[0] = NODEDATA(node);
} else {
rc = mdbx_xcursor_init1(m3, node);
if (unlikely(rc != MDBX_SUCCESS))
break;
m3->mc_xcursor->mx_cursor.mc_flags |= C_DEL;
}
}
}
}
}
}
if (mc->mc_ki[mc->mc_top] >= nkeys) {
rc = mdbx_cursor_sibling(mc, true);
if (rc == MDBX_NOTFOUND) {
mc->mc_flags |= C_EOF;
rc = MDBX_SUCCESS;
}
}
if ((mc->mc_db->md_flags & MDBX_DUPSORT) != 0 &&
(mc->mc_flags & C_EOF) == 0) {
MDBX_node *node = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
/* If this node has dupdata, it may need to be reinited
* because its data has moved.
* If the xcursor was not initd it must be reinited.
* Else if node points to a subDB, nothing is needed. */
if (node->mn_flags & F_DUPDATA) {
if (mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) {
if (!(node->mn_flags & F_SUBDATA))
mc->mc_xcursor->mx_cursor.mc_pg[0] = NODEDATA(node);
} else {
rc = mdbx_xcursor_init1(mc, node);
if (likely(rc != MDBX_SUCCESS))
mc->mc_xcursor->mx_cursor.mc_flags |= C_DEL;
}
}
}
mc->mc_flags |= C_DEL;
}
if (unlikely(rc))
mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
else if (mdbx_audit_enabled())
rc = mdbx_cursor_check(mc, false);
return rc;
}
int mdbx_del(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data) {
if (unlikely(!key || !txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
if (unlikely(txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_BLOCKED)))
return (txn->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EACCESS : MDBX_BAD_TXN;
return mdbx_del0(txn, dbi, key, data, 0);
}
static int mdbx_del0(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
unsigned flags) {
MDBX_cursor_couple cx;
MDBX_cursor_op op;
MDBX_val rdata;
int rc, exact = 0;
DKBUF;
mdbx_debug("====> delete db %u key [%s], data [%s]", dbi, DKEY(key),
DVAL(data));
rc = mdbx_cursor_init(&cx.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
if (data) {
op = MDBX_GET_BOTH;
rdata = *data;
data = &rdata;
} else {
op = MDBX_SET;
flags |= MDBX_NODUPDATA;
}
rc = mdbx_cursor_set(&cx.outer, key, data, op, &exact);
if (likely(rc == MDBX_SUCCESS)) {
/* let mdbx_page_split know about this cursor if needed:
* delete will trigger a rebalance; if it needs to move
* a node from one page to another, it will have to
* update the parent's separator key(s). If the new sepkey
* is larger than the current one, the parent page may
* run out of space, triggering a split. We need this
* cursor to be consistent until the end of the rebalance. */
cx.outer.mc_next = txn->mt_cursors[dbi];
txn->mt_cursors[dbi] = &cx.outer;
rc = mdbx_cursor_del(&cx.outer, flags);
txn->mt_cursors[dbi] = cx.outer.mc_next;
}
return rc;
}
/* Split a page and insert a new node.
* Set MDBX_TXN_ERROR on failure.
* [in,out] mc Cursor pointing to the page and desired insertion index.
* The cursor will be updated to point to the actual page and index where
* the node got inserted after the split.
* [in] newkey The key for the newly inserted node.
* [in] newdata The data for the newly inserted node.
* [in] newpgno The page number, if the new node is a branch node.
* [in] nflags The NODE_ADD_FLAGS for the new node.
* Returns 0 on success, non-zero on failure. */
static int mdbx_page_split(MDBX_cursor *mc, const MDBX_val *newkey,
MDBX_val *newdata, pgno_t newpgno, unsigned nflags) {
unsigned flags;
int rc = MDBX_SUCCESS, foliage = 0, did_split = 0;
pgno_t pgno = 0;
unsigned i, ptop;
MDBX_env *env = mc->mc_txn->mt_env;
MDBX_node *node;
MDBX_val sepkey, rkey, xdata;
MDBX_page *copy = NULL;
MDBX_page *rp, *pp;
MDBX_cursor mn;
DKBUF;
MDBX_page *mp = mc->mc_pg[mc->mc_top];
unsigned newindx = mc->mc_ki[mc->mc_top];
unsigned nkeys = NUMKEYS(mp);
if (mdbx_audit_enabled()) {
int err = mdbx_cursor_check(mc, true);
if (unlikely(err != MDBX_SUCCESS))
return err;
}
mdbx_debug("-----> splitting %s page %" PRIaPGNO
" and adding [%s] at index %i/%i",
IS_LEAF(mp) ? "leaf" : "branch", mp->mp_pgno, DKEY(newkey),
mc->mc_ki[mc->mc_top], nkeys);
/* Create a right sibling. */
if ((rc = mdbx_page_new(mc, mp->mp_flags, 1, &rp)))
return rc;
rp->mp_leaf2_ksize = mp->mp_leaf2_ksize;
mdbx_debug("new right sibling: page %" PRIaPGNO, rp->mp_pgno);
/* Usually when splitting the root page, the cursor
* height is 1. But when called from mdbx_update_key,
* the cursor height may be greater because it walks
* up the stack while finding the branch slot to update. */
if (mc->mc_top < 1) {
if ((rc = mdbx_page_new(mc, P_BRANCH, 1, &pp)))
goto done;
/* shift current top to make room for new parent */
mdbx_cassert(mc, mc->mc_snum < 2 && mc->mc_db->md_depth > 0);
mc->mc_pg[2] = mc->mc_pg[1];
mc->mc_ki[2] = mc->mc_ki[1];
mc->mc_pg[1] = mc->mc_pg[0];
mc->mc_ki[1] = mc->mc_ki[0];
mc->mc_pg[0] = pp;
mc->mc_ki[0] = 0;
mc->mc_db->md_root = pp->mp_pgno;
mdbx_debug("root split! new root = %" PRIaPGNO, pp->mp_pgno);
foliage = mc->mc_db->md_depth++;
/* Add left (implicit) pointer. */
if (unlikely((rc = mdbx_node_add_branch(mc, 0, NULL, mp->mp_pgno)) !=
MDBX_SUCCESS)) {
/* undo the pre-push */
mc->mc_pg[0] = mc->mc_pg[1];
mc->mc_ki[0] = mc->mc_ki[1];
mc->mc_db->md_root = mp->mp_pgno;
mc->mc_db->md_depth--;
goto done;
}
mc->mc_snum++;
mc->mc_top++;
ptop = 0;
} else {
ptop = mc->mc_top - 1;
mdbx_debug("parent branch page is %" PRIaPGNO, mc->mc_pg[ptop]->mp_pgno);
}
mdbx_cursor_copy(mc, &mn);
mn.mc_xcursor = NULL;
mn.mc_pg[mn.mc_top] = rp;
mn.mc_ki[mn.mc_top] = 0;
mn.mc_ki[ptop] = mc->mc_ki[ptop] + 1;
unsigned split_indx;
if (nflags & MDBX_APPEND) {
mn.mc_ki[mn.mc_top] = 0;
sepkey = *newkey;
split_indx = newindx;
nkeys = 0;
} else {
split_indx = (nkeys + 1) / 2;
if (IS_LEAF2(rp)) {
char *split, *ins;
int x;
unsigned lsize, rsize, ksize;
/* Move half of the keys to the right sibling */
x = mc->mc_ki[mc->mc_top] - split_indx;
ksize = mc->mc_db->md_xsize;
split = LEAF2KEY(mp, split_indx, ksize);
rsize = (nkeys - split_indx) * ksize;
lsize = (nkeys - split_indx) * sizeof(indx_t);
mdbx_cassert(mc, mp->mp_lower >= lsize);
mp->mp_lower -= (indx_t)lsize;
mdbx_cassert(mc, rp->mp_lower + lsize <= UINT16_MAX);
rp->mp_lower += (indx_t)lsize;
mdbx_cassert(mc, mp->mp_upper + rsize - lsize <= UINT16_MAX);
mp->mp_upper += (indx_t)(rsize - lsize);
mdbx_cassert(mc, rp->mp_upper >= rsize - lsize);
rp->mp_upper -= (indx_t)(rsize - lsize);
sepkey.iov_len = ksize;
if (newindx == split_indx) {
sepkey.iov_base = newkey->iov_base;
} else {
sepkey.iov_base = split;
}
if (x < 0) {
mdbx_cassert(mc, ksize >= sizeof(indx_t));
ins = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], ksize);
memcpy(rp->mp_ptrs, split, rsize);
sepkey.iov_base = rp->mp_ptrs;
memmove(ins + ksize, ins, (split_indx - mc->mc_ki[mc->mc_top]) * ksize);
memcpy(ins, newkey->iov_base, ksize);
mdbx_cassert(mc, UINT16_MAX - mp->mp_lower >= (int)sizeof(indx_t));
mp->mp_lower += sizeof(indx_t);
mdbx_cassert(mc, mp->mp_upper >= ksize - sizeof(indx_t));
mp->mp_upper -= (indx_t)(ksize - sizeof(indx_t));
} else {
if (x)
memcpy(rp->mp_ptrs, split, x * ksize);
ins = LEAF2KEY(rp, x, ksize);
memcpy(ins, newkey->iov_base, ksize);
memcpy(ins + ksize, split + x * ksize, rsize - x * ksize);
mdbx_cassert(mc, UINT16_MAX - rp->mp_lower >= (int)sizeof(indx_t));
rp->mp_lower += sizeof(indx_t);
mdbx_cassert(mc, rp->mp_upper >= ksize - sizeof(indx_t));
rp->mp_upper -= (indx_t)(ksize - sizeof(indx_t));
mdbx_cassert(mc, x <= UINT16_MAX);
mc->mc_ki[mc->mc_top] = (indx_t)x;
}
} else {
size_t psize, nsize, k;
/* Maximum free space in an empty page */
const unsigned pmax = env->me_psize - PAGEHDRSZ;
nsize = IS_LEAF(mp) ? mdbx_leaf_size(env, newkey, newdata)
: mdbx_branch_size(env, newkey);
/* grab a page to hold a temporary copy */
copy = mdbx_page_malloc(mc->mc_txn, 1);
if (unlikely(copy == NULL)) {
rc = MDBX_ENOMEM;
goto done;
}
copy->mp_pgno = mp->mp_pgno;
copy->mp_flags = mp->mp_flags;
copy->mp_lower = 0;
mdbx_cassert(mc, env->me_psize - PAGEHDRSZ <= UINT16_MAX);
copy->mp_upper = (indx_t)(env->me_psize - PAGEHDRSZ);
/* prepare to insert */
for (unsigned j = i = 0; i < nkeys; i++) {
if (i == newindx)
copy->mp_ptrs[j++] = 0;
copy->mp_ptrs[j++] = mp->mp_ptrs[i];
}
/* When items are relatively large the split point needs
* to be checked, because being off-by-one will make the
* difference between success or failure in mdbx_node_add.
*
* It's also relevant if a page happens to be laid out
* such that one half of its nodes are all "small" and
* the other half of its nodes are "large." If the new
* item is also "large" and falls on the half with
* "large" nodes, it also may not fit.
*
* As a final tweak, if the new item goes on the last
* spot on the page (and thus, onto the new page), bias
* the split so the new page is emptier than the old page.
* This yields better packing during sequential inserts.
*/
int dir;
if (nkeys < 32 || nsize > pmax / 16 || newindx >= nkeys) {
/* Find split point */
psize = 0;
if (newindx <= split_indx || newindx >= nkeys) {
i = 0;
dir = 1;
k = (newindx >= nkeys) ? nkeys : split_indx + 1 + IS_LEAF(mp);
} else {
i = nkeys;
dir = -1;
k = split_indx - 1;
}
for (; i != k; i += dir) {
if (i == newindx) {
psize += nsize;
node = NULL;
} else {
node = (MDBX_node *)((char *)mp + copy->mp_ptrs[i] + PAGEHDRSZ);
psize += NODESIZE + NODEKSZ(node) + sizeof(indx_t);
if (IS_LEAF(mp)) {
if (F_ISSET(node->mn_flags, F_BIGDATA))
psize += sizeof(pgno_t);
else
psize += NODEDSZ(node);
}
psize = EVEN(psize);
}
if (psize > pmax || i == k - dir) {
split_indx = i + (dir < 0);
break;
}
}
}
if (split_indx == newindx) {
sepkey.iov_len = newkey->iov_len;
sepkey.iov_base = newkey->iov_base;
} else {
node =
(MDBX_node *)((char *)mp + copy->mp_ptrs[split_indx] + PAGEHDRSZ);
sepkey.iov_len = node->mn_ksize;
sepkey.iov_base = NODEKEY(node);
}
}
}
mdbx_debug("separator is %d [%s]", split_indx, DKEY(&sepkey));
if (mdbx_audit_enabled()) {
int err = mdbx_cursor_check(mc, true);
if (unlikely(err != MDBX_SUCCESS))
return err;
err = mdbx_cursor_check(&mn, true);
if (unlikely(err != MDBX_SUCCESS))
return err;
}
/* Copy separator key to the parent. */
if (SIZELEFT(mn.mc_pg[ptop]) < mdbx_branch_size(env, &sepkey)) {
const int snum = mc->mc_snum;
const int depth = mc->mc_db->md_depth;
mn.mc_snum--;
mn.mc_top--;
did_split = 1;
/* We want other splits to find mn when doing fixups */
WITH_CURSOR_TRACKING(
mn, rc = mdbx_page_split(&mn, &sepkey, NULL, rp->mp_pgno, 0));
if (unlikely(rc != MDBX_SUCCESS))
goto done;
mdbx_cassert(mc, mc->mc_snum - snum == mc->mc_db->md_depth - depth);
if (mdbx_audit_enabled()) {
int err = mdbx_cursor_check(mc, true);
if (unlikely(err != MDBX_SUCCESS))
return err;
}
/* root split? */
ptop += mc->mc_snum - snum;
/* Right page might now have changed parent.
* Check if left page also changed parent. */
if (mn.mc_pg[ptop] != mc->mc_pg[ptop] &&
mc->mc_ki[ptop] >= NUMKEYS(mc->mc_pg[ptop])) {
for (i = 0; i < ptop; i++) {
mc->mc_pg[i] = mn.mc_pg[i];
mc->mc_ki[i] = mn.mc_ki[i];
}
mc->mc_pg[ptop] = mn.mc_pg[ptop];
if (mn.mc_ki[ptop]) {
mc->mc_ki[ptop] = mn.mc_ki[ptop] - 1;
} else {
/* find right page's left sibling */
mc->mc_ki[ptop] = mn.mc_ki[ptop];
rc = mdbx_cursor_sibling(mc, false);
}
}
} else {
mn.mc_top--;
rc = mdbx_node_add_branch(&mn, mn.mc_ki[ptop], &sepkey, rp->mp_pgno);
mn.mc_top++;
}
if (unlikely(rc != MDBX_SUCCESS)) {
if (rc == MDBX_NOTFOUND) /* improper mdbx_cursor_sibling() result */ {
mdbx_error("unexpected %s", "MDBX_NOTFOUND");
rc = MDBX_PROBLEM;
}
goto done;
}
if (nflags & MDBX_APPEND) {
mc->mc_pg[mc->mc_top] = rp;
mc->mc_ki[mc->mc_top] = 0;
switch (PAGETYPE(rp)) {
case P_BRANCH: {
mdbx_cassert(mc, (nflags & (F_BIGDATA | F_SUBDATA | F_DUPDATA)) == 0);
mdbx_cassert(mc, newpgno != 0 && newpgno != P_INVALID);
rc = mdbx_node_add_branch(mc, 0, newkey, newpgno);
} break;
case P_LEAF: {
mdbx_cassert(mc, newpgno == 0 || newpgno == P_INVALID);
rc = mdbx_node_add_leaf(mc, 0, newkey, newdata, nflags);
} break;
case P_LEAF | P_LEAF2: {
mdbx_cassert(mc, (nflags & (F_BIGDATA | F_SUBDATA | F_DUPDATA)) == 0);
mdbx_cassert(mc, newpgno == 0 || newpgno == P_INVALID);
rc = mdbx_node_add_leaf2(mc, 0, newkey);
} break;
default:
rc = MDBX_CORRUPTED;
}
if (rc)
goto done;
for (i = 0; i < mc->mc_top; i++)
mc->mc_ki[i] = mn.mc_ki[i];
} else if (!IS_LEAF2(mp)) {
/* Move nodes */
mc->mc_pg[mc->mc_top] = rp;
i = split_indx;
indx_t n = 0;
do {
MDBX_val *rdata = NULL;
if (i == newindx) {
rkey.iov_base = newkey->iov_base;
rkey.iov_len = newkey->iov_len;
if (IS_LEAF(mp)) {
rdata = newdata;
} else
pgno = newpgno;
flags = nflags;
/* Update index for the new key. */
mc->mc_ki[mc->mc_top] = n;
} else {
node = (MDBX_node *)((char *)mp + copy->mp_ptrs[i] + PAGEHDRSZ);
rkey.iov_base = NODEKEY(node);
rkey.iov_len = node->mn_ksize;
if (IS_LEAF(mp)) {
xdata.iov_base = NODEDATA(node);
xdata.iov_len = NODEDSZ(node);
rdata = &xdata;
} else
pgno = NODEPGNO(node);
flags = node->mn_flags;
}
switch (PAGETYPE(rp)) {
case P_BRANCH: {
mdbx_cassert(mc, 0 == (uint16_t)flags);
if (n == 0) {
/* First branch index doesn't need key data. */
rkey.iov_len = 0;
}
rc = mdbx_node_add_branch(mc, n, &rkey, pgno);
} break;
case P_LEAF: {
mdbx_cassert(mc, pgno == 0);
mdbx_cassert(mc, rdata != NULL);
rc = mdbx_node_add_leaf(mc, n, &rkey, rdata, flags);
} break;
/* case P_LEAF | P_LEAF2: {
mdbx_cassert(mc, (nflags & (F_BIGDATA | F_SUBDATA | F_DUPDATA)) == 0);
mdbx_cassert(mc, gno == 0);
rc = mdbx_node_add_leaf2(mc, n, &rkey);
} break; */
default:
rc = MDBX_CORRUPTED;
}
if (rc)
goto done;
if (i == nkeys) {
i = 0;
n = 0;
mc->mc_pg[mc->mc_top] = copy;
} else {
i++;
n++;
}
} while (i != split_indx);
nkeys = NUMKEYS(copy);
for (i = 0; i < nkeys; i++)
mp->mp_ptrs[i] = copy->mp_ptrs[i];
mp->mp_lower = copy->mp_lower;
mp->mp_upper = copy->mp_upper;
memcpy(NODEPTR(mp, nkeys - 1), NODEPTR(copy, nkeys - 1),
env->me_psize - copy->mp_upper - PAGEHDRSZ);
/* reset back to original page */
if (newindx < split_indx) {
mc->mc_pg[mc->mc_top] = mp;
} else {
mc->mc_pg[mc->mc_top] = rp;
mc->mc_ki[ptop]++;
/* Make sure mc_ki is still valid. */
if (mn.mc_pg[ptop] != mc->mc_pg[ptop] &&
mc->mc_ki[ptop] >= NUMKEYS(mc->mc_pg[ptop])) {
for (i = 0; i <= ptop; i++) {
mc->mc_pg[i] = mn.mc_pg[i];
mc->mc_ki[i] = mn.mc_ki[i];
}
}
}
if (nflags & MDBX_RESERVE) {
node = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
if (!(node->mn_flags & F_BIGDATA))
newdata->iov_base = NODEDATA(node);
}
} else {
if (newindx >= split_indx) {
mc->mc_pg[mc->mc_top] = rp;
mc->mc_ki[ptop]++;
/* Make sure mc_ki is still valid. */
if (mn.mc_pg[ptop] != mc->mc_pg[ptop] &&
mc->mc_ki[ptop] >= NUMKEYS(mc->mc_pg[ptop])) {
for (i = 0; i <= ptop; i++) {
mc->mc_pg[i] = mn.mc_pg[i];
mc->mc_ki[i] = mn.mc_ki[i];
}
}
}
}
{
/* Adjust other cursors pointing to mp */
MDBX_cursor *m2, *m3;
MDBX_dbi dbi = mc->mc_dbi;
nkeys = NUMKEYS(mp);
for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2 = m2->mc_next) {
m3 = (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
if (m3 == mc)
continue;
if (!(m2->mc_flags & m3->mc_flags & C_INITIALIZED))
continue;
if (foliage) {
int k;
/* sub cursors may be on different DB */
if (m3->mc_pg[0] != mp)
continue;
/* root split */
for (k = foliage; k >= 0; k--) {
m3->mc_ki[k + 1] = m3->mc_ki[k];
m3->mc_pg[k + 1] = m3->mc_pg[k];
}
m3->mc_ki[0] = (m3->mc_ki[0] >= nkeys) ? 1 : 0;
m3->mc_pg[0] = mc->mc_pg[0];
m3->mc_snum++;
m3->mc_top++;
}
if (m3->mc_top >= mc->mc_top && m3->mc_pg[mc->mc_top] == mp) {
if (m3->mc_ki[mc->mc_top] >= newindx && !(nflags & MDBX_SPLIT_REPLACE))
m3->mc_ki[mc->mc_top]++;
if (m3->mc_ki[mc->mc_top] >= nkeys) {
m3->mc_pg[mc->mc_top] = rp;
mdbx_cassert(mc, m3->mc_ki[mc->mc_top] >= nkeys);
m3->mc_ki[mc->mc_top] -= (indx_t)nkeys;
for (i = 0; i < mc->mc_top; i++) {
m3->mc_ki[i] = mn.mc_ki[i];
m3->mc_pg[i] = mn.mc_pg[i];
}
}
} else if (!did_split && m3->mc_top >= ptop &&
m3->mc_pg[ptop] == mc->mc_pg[ptop] &&
m3->mc_ki[ptop] >= mc->mc_ki[ptop]) {
m3->mc_ki[ptop]++;
}
if (XCURSOR_INITED(m3) && IS_LEAF(mp))
XCURSOR_REFRESH(m3, m3->mc_pg[mc->mc_top], m3->mc_ki[mc->mc_top]);
}
}
mdbx_debug("mp left: %d, rp left: %d", SIZELEFT(mp), SIZELEFT(rp));
done:
if (copy) /* tmp page */
mdbx_dpage_free(env, copy, 1);
if (unlikely(rc))
mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
return rc;
}
int mdbx_put(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
unsigned flags) {
if (unlikely(!key || !data || !txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
if (unlikely(flags & ~(MDBX_NOOVERWRITE | MDBX_NODUPDATA | MDBX_RESERVE |
MDBX_APPEND | MDBX_APPENDDUP | MDBX_CURRENT)))
return MDBX_EINVAL;
if (unlikely(txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_BLOCKED)))
return (txn->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EACCESS : MDBX_BAD_TXN;
MDBX_cursor_couple cx;
int rc = mdbx_cursor_init(&cx.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
cx.outer.mc_next = txn->mt_cursors[dbi];
txn->mt_cursors[dbi] = &cx.outer;
/* LY: support for update (explicit overwrite) */
if (flags & MDBX_CURRENT) {
rc = mdbx_cursor_get(&cx.outer, key, NULL, MDBX_SET);
if (likely(rc == MDBX_SUCCESS) &&
(txn->mt_dbs[dbi].md_flags & MDBX_DUPSORT)) {
/* LY: allows update (explicit overwrite) only for unique keys */
MDBX_node *leaf = NODEPTR(cx.outer.mc_pg[cx.outer.mc_top],
cx.outer.mc_ki[cx.outer.mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
mdbx_tassert(txn, XCURSOR_INITED(&cx.outer) &&
cx.outer.mc_xcursor->mx_db.md_entries > 1);
rc = MDBX_EMULTIVAL;
}
}
}
if (likely(rc == MDBX_SUCCESS))
rc = mdbx_cursor_put(&cx.outer, key, data, flags);
txn->mt_cursors[dbi] = cx.outer.mc_next;
return rc;
}
#ifndef MDBX_WBUF
#define MDBX_WBUF (1024 * 1024)
#endif
#define MDBX_EOF 0x10 /* mdbx_env_copyfd1() is done reading */
/* State needed for a double-buffering compacting copy. */
typedef struct mdbx_copy {
MDBX_env *mc_env;
MDBX_txn *mc_txn;
mdbx_condmutex_t mc_condmutex;
uint8_t *mc_wbuf[2];
uint8_t *mc_over[2];
size_t mc_wlen[2];
size_t mc_olen[2];
mdbx_filehandle_t mc_fd;
volatile int mc_error;
pgno_t mc_next_pgno;
short mc_toggle; /* Buffer number in provider */
short mc_new; /* (0-2 buffers to write) | (MDBX_EOF at end) */
/* Error code. Never cleared if set. Both threads can set nonzero
* to fail the copy. Not mutex-protected, MDBX expects atomic int. */
} mdbx_copy;
/* Dedicated writer thread for compacting copy. */
static THREAD_RESULT __cold THREAD_CALL mdbx_env_copythr(void *arg) {
mdbx_copy *my = arg;
uint8_t *ptr;
int toggle = 0;
int rc;
#if defined(F_SETNOSIGPIPE)
/* OS X delivers SIGPIPE to the whole process, not the thread that caused it.
* Disable SIGPIPE using platform specific fcntl. */
int enabled = 1;
if (fcntl(my->mc_fd, F_SETNOSIGPIPE, &enabled))
my->mc_error = errno;
#endif
#if defined(SIGPIPE) && !defined(_WIN32) && !defined(_WIN64)
sigset_t set;
sigemptyset(&set);
sigaddset(&set, SIGPIPE);
rc = pthread_sigmask(SIG_BLOCK, &set, NULL);
if (rc != 0)
my->mc_error = rc;
#endif
mdbx_condmutex_lock(&my->mc_condmutex);
while (!my->mc_error) {
while (!my->mc_new)
mdbx_condmutex_wait(&my->mc_condmutex);
if (my->mc_new == 0 + MDBX_EOF) /* 0 buffers, just EOF */
break;
size_t wsize = my->mc_wlen[toggle];
ptr = my->mc_wbuf[toggle];
again:
if (wsize > 0 && !my->mc_error) {
rc = mdbx_write(my->mc_fd, ptr, wsize);
if (rc != MDBX_SUCCESS) {
#if defined(SIGPIPE) && !defined(_WIN32) && !defined(_WIN64)
if (rc == EPIPE) {
/* Collect the pending SIGPIPE, otherwise (at least OS X)
* gives it to the process on thread-exit (ITS#8504). */
int tmp;
sigwait(&set, &tmp);
}
#endif
my->mc_error = rc;
}
}
/* If there's an overflow page tail, write it too */
if (my->mc_olen[toggle]) {
wsize = my->mc_olen[toggle];
ptr = my->mc_over[toggle];
my->mc_olen[toggle] = 0;
goto again;
}
my->mc_wlen[toggle] = 0;
toggle ^= 1;
/* Return the empty buffer to provider */
my->mc_new--;
mdbx_condmutex_signal(&my->mc_condmutex);
}
mdbx_condmutex_unlock(&my->mc_condmutex);
return (THREAD_RESULT)0;
}
/* Give buffer and/or MDBX_EOF to writer thread, await unused buffer.
*
* [in] my control structure.
* [in] adjust (1 to hand off 1 buffer) | (MDBX_EOF when ending). */
static int __cold mdbx_env_cthr_toggle(mdbx_copy *my, int adjust) {
mdbx_condmutex_lock(&my->mc_condmutex);
my->mc_new += (short)adjust;
mdbx_condmutex_signal(&my->mc_condmutex);
while (my->mc_new & 2) /* both buffers in use */
mdbx_condmutex_wait(&my->mc_condmutex);
mdbx_condmutex_unlock(&my->mc_condmutex);
my->mc_toggle ^= (adjust & 1);
/* Both threads reset mc_wlen, to be safe from threading errors */
my->mc_wlen[my->mc_toggle] = 0;
return my->mc_error;
}
/* Depth-first tree traversal for compacting copy.
* [in] my control structure.
* [in,out] pg database root.
* [in] flags includes F_DUPDATA if it is a sorted-duplicate sub-DB. */
static int __cold mdbx_env_cwalk(mdbx_copy *my, pgno_t *pg, int flags) {
MDBX_cursor mc;
MDBX_node *ni;
MDBX_page *mo, *mp, *leaf;
char *buf, *ptr;
int rc, toggle;
unsigned i;
/* Empty DB, nothing to do */
if (*pg == P_INVALID)
return MDBX_SUCCESS;
memset(&mc, 0, sizeof(mc));
mc.mc_snum = 1;
mc.mc_txn = my->mc_txn;
rc = mdbx_page_get(&mc, *pg, &mc.mc_pg[0], NULL);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
rc = mdbx_page_search_root(&mc, NULL, MDBX_PS_FIRST);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
/* Make cursor pages writable */
buf = ptr = mdbx_malloc(pgno2bytes(my->mc_env, mc.mc_snum));
if (buf == NULL)
return MDBX_ENOMEM;
for (i = 0; i < mc.mc_top; i++) {
mdbx_page_copy((MDBX_page *)ptr, mc.mc_pg[i], my->mc_env->me_psize);
mc.mc_pg[i] = (MDBX_page *)ptr;
ptr += my->mc_env->me_psize;
}
/* This is writable space for a leaf page. Usually not needed. */
leaf = (MDBX_page *)ptr;
toggle = my->mc_toggle;
while (mc.mc_snum > 0) {
unsigned n;
mp = mc.mc_pg[mc.mc_top];
n = NUMKEYS(mp);
if (IS_LEAF(mp)) {
if (!IS_LEAF2(mp) && !(flags & F_DUPDATA)) {
for (i = 0; i < n; i++) {
ni = NODEPTR(mp, i);
if (ni->mn_flags & F_BIGDATA) {
MDBX_page *omp;
/* Need writable leaf */
if (mp != leaf) {
mc.mc_pg[mc.mc_top] = leaf;
mdbx_page_copy(leaf, mp, my->mc_env->me_psize);
mp = leaf;
ni = NODEPTR(mp, i);
}
pgno_t pgno;
memcpy(&pgno, NODEDATA(ni), sizeof(pgno));
memcpy(NODEDATA(ni), &my->mc_next_pgno, sizeof(pgno_t));
rc = mdbx_page_get(&mc, pgno, &omp, NULL);
if (unlikely(rc != MDBX_SUCCESS))
goto done;
if (my->mc_wlen[toggle] >= MDBX_WBUF) {
rc = mdbx_env_cthr_toggle(my, 1);
if (unlikely(rc != MDBX_SUCCESS))
goto done;
toggle = my->mc_toggle;
}
mo = (MDBX_page *)(my->mc_wbuf[toggle] + my->mc_wlen[toggle]);
memcpy(mo, omp, my->mc_env->me_psize);
mo->mp_pgno = my->mc_next_pgno;
my->mc_next_pgno += omp->mp_pages;
my->mc_wlen[toggle] += my->mc_env->me_psize;
if (omp->mp_pages > 1) {
my->mc_olen[toggle] = pgno2bytes(my->mc_env, omp->mp_pages - 1);
my->mc_over[toggle] = (uint8_t *)omp + my->mc_env->me_psize;
rc = mdbx_env_cthr_toggle(my, 1);
if (unlikely(rc != MDBX_SUCCESS))
goto done;
toggle = my->mc_toggle;
}
} else if (ni->mn_flags & F_SUBDATA) {
MDBX_db db;
/* Need writable leaf */
if (mp != leaf) {
mc.mc_pg[mc.mc_top] = leaf;
mdbx_page_copy(leaf, mp, my->mc_env->me_psize);
mp = leaf;
ni = NODEPTR(mp, i);
}
memcpy(&db, NODEDATA(ni), sizeof(db));
my->mc_toggle = (short)toggle;
rc = mdbx_env_cwalk(my, &db.md_root, ni->mn_flags & F_DUPDATA);
if (rc)
goto done;
toggle = my->mc_toggle;
memcpy(NODEDATA(ni), &db, sizeof(db));
}
}
}
} else {
mc.mc_ki[mc.mc_top]++;
if (mc.mc_ki[mc.mc_top] < n) {
pgno_t pgno;
again:
ni = NODEPTR(mp, mc.mc_ki[mc.mc_top]);
pgno = NODEPGNO(ni);
rc = mdbx_page_get(&mc, pgno, &mp, NULL);
if (unlikely(rc != MDBX_SUCCESS))
goto done;
mc.mc_top++;
mc.mc_snum++;
mc.mc_ki[mc.mc_top] = 0;
if (IS_BRANCH(mp)) {
/* Whenever we advance to a sibling branch page,
* we must proceed all the way down to its first leaf. */
mdbx_page_copy(mc.mc_pg[mc.mc_top], mp, my->mc_env->me_psize);
goto again;
} else
mc.mc_pg[mc.mc_top] = mp;
continue;
}
}
if (my->mc_wlen[toggle] >= MDBX_WBUF) {
rc = mdbx_env_cthr_toggle(my, 1);
if (unlikely(rc != MDBX_SUCCESS))
goto done;
toggle = my->mc_toggle;
}
mo = (MDBX_page *)(my->mc_wbuf[toggle] + my->mc_wlen[toggle]);
mdbx_page_copy(mo, mp, my->mc_env->me_psize);
mo->mp_pgno = my->mc_next_pgno++;
my->mc_wlen[toggle] += my->mc_env->me_psize;
if (mc.mc_top) {
/* Update parent if there is one */
ni = NODEPTR(mc.mc_pg[mc.mc_top - 1], mc.mc_ki[mc.mc_top - 1]);
SETPGNO(ni, mo->mp_pgno);
mdbx_cursor_pop(&mc);
} else {
/* Otherwise we're done */
*pg = mo->mp_pgno;
break;
}
}
done:
mdbx_free(buf);
return rc;
}
/* Copy environment with compaction. */
static int __cold mdbx_env_compact(MDBX_env *env, MDBX_txn *read_txn,
mdbx_filehandle_t fd, uint8_t *buffer) {
MDBX_page *const meta = mdbx_init_metas(env, buffer);
/* copy canary sequenses if present */
if (read_txn->mt_canary.v) {
meta->mp_meta.mm_canary = read_txn->mt_canary;
meta->mp_meta.mm_canary.v = mdbx_meta_txnid_stable(env, &meta->mp_meta);
}
/* Set metapage 1 with current main DB */
pgno_t new_root, root = read_txn->mt_dbs[MAIN_DBI].md_root;
if ((new_root = root) == P_INVALID) {
/* When the DB is empty, handle it specially to
* fix any breakage like page leaks from ITS#8174. */
meta->mp_meta.mm_dbs[MAIN_DBI].md_flags =
read_txn->mt_dbs[MAIN_DBI].md_flags;
} else {
/* Count free pages + freeDB pages. Subtract from last_pg
* to find the new last_pg, which also becomes the new root. */
pgno_t freecount = 0;
MDBX_cursor mc;
MDBX_val key, data;
int rc = mdbx_cursor_init(&mc, read_txn, FREE_DBI);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
while ((rc = mdbx_cursor_get(&mc, &key, &data, MDBX_NEXT)) == 0)
freecount += *(pgno_t *)data.iov_base;
if (unlikely(rc != MDBX_NOTFOUND))
return rc;
freecount += read_txn->mt_dbs[FREE_DBI].md_branch_pages +
read_txn->mt_dbs[FREE_DBI].md_leaf_pages +
read_txn->mt_dbs[FREE_DBI].md_overflow_pages;
new_root = read_txn->mt_next_pgno - 1 - freecount;
meta->mp_meta.mm_geo.next = new_root + 1;
meta->mp_meta.mm_dbs[MAIN_DBI] = read_txn->mt_dbs[MAIN_DBI];
meta->mp_meta.mm_dbs[MAIN_DBI].md_root = new_root;
mdbx_copy ctx;
memset(&ctx, 0, sizeof(ctx));
rc = mdbx_condmutex_init(&ctx.mc_condmutex);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
ctx.mc_wbuf[0] = buffer + pgno2bytes(env, NUM_METAS);
memset(ctx.mc_wbuf[0], 0, MDBX_WBUF * 2);
ctx.mc_wbuf[1] = ctx.mc_wbuf[0] + MDBX_WBUF;
ctx.mc_next_pgno = NUM_METAS;
ctx.mc_env = env;
ctx.mc_fd = fd;
ctx.mc_txn = read_txn;
mdbx_thread_t thread;
int thread_err = mdbx_thread_create(&thread, mdbx_env_copythr, &ctx);
if (likely(thread_err == MDBX_SUCCESS)) {
rc = mdbx_env_cwalk(&ctx, &root, 0);
mdbx_env_cthr_toggle(&ctx, 1 | MDBX_EOF);
thread_err = mdbx_thread_join(thread);
mdbx_condmutex_destroy(&ctx.mc_condmutex);
}
if (unlikely(thread_err != MDBX_SUCCESS))
return thread_err;
if (unlikely(rc != MDBX_SUCCESS))
return rc;
if (unlikely(ctx.mc_error != MDBX_SUCCESS))
return ctx.mc_error;
if (root > new_root) {
mdbx_error("post-compactification root %" PRIaPGNO
" GT expected %" PRIaPGNO " (source DB corrupted)",
root, new_root);
return MDBX_CORRUPTED; /* page leak or corrupt DB */
}
if (root < new_root) {
mdbx_notice("post-compactification root %" PRIaPGNO
" LT expected %" PRIaPGNO " (page leak(s) in source DB)",
root, new_root);
/* fixup meta */
meta->mp_meta.mm_dbs[MAIN_DBI].md_root = root;
meta->mp_meta.mm_geo.next = root + 1;
}
}
/* Calculate filesize taking in account shrink/growing thresholds */
if (meta->mp_meta.mm_geo.next > meta->mp_meta.mm_geo.now) {
const pgno_t aligned =
pgno_align2os_pgno(env, pgno_add(meta->mp_meta.mm_geo.next,
meta->mp_meta.mm_geo.grow -
meta->mp_meta.mm_geo.next %
meta->mp_meta.mm_geo.grow));
meta->mp_meta.mm_geo.now = aligned;
} else if (meta->mp_meta.mm_geo.next < meta->mp_meta.mm_geo.now) {
meta->mp_meta.mm_geo.now = meta->mp_meta.mm_geo.next;
const pgno_t aligner = meta->mp_meta.mm_geo.grow
? meta->mp_meta.mm_geo.grow
: meta->mp_meta.mm_geo.shrink;
const pgno_t aligned =
pgno_align2os_pgno(env, meta->mp_meta.mm_geo.next + aligner -
meta->mp_meta.mm_geo.next % aligner);
meta->mp_meta.mm_geo.now = aligned;
}
if (meta->mp_meta.mm_geo.now < meta->mp_meta.mm_geo.lower)
meta->mp_meta.mm_geo.now = meta->mp_meta.mm_geo.lower;
if (meta->mp_meta.mm_geo.now > meta->mp_meta.mm_geo.upper)
meta->mp_meta.mm_geo.now = meta->mp_meta.mm_geo.upper;
/* Update signature */
assert(meta->mp_meta.mm_geo.now >= meta->mp_meta.mm_geo.next);
meta->mp_meta.mm_datasync_sign = mdbx_meta_sign(&meta->mp_meta);
/* Extend file if required */
return (meta->mp_meta.mm_geo.now != meta->mp_meta.mm_geo.next)
? mdbx_ftruncate(fd, pgno2bytes(env, meta->mp_meta.mm_geo.now))
: MDBX_SUCCESS;
}
/* Copy environment as-is. */
static int __cold mdbx_env_copy_asis(MDBX_env *env, MDBX_txn *read_txn,
mdbx_filehandle_t fd, uint8_t *buffer) {
/* We must start the actual read txn after blocking writers */
int rc = mdbx_txn_end(read_txn, MDBX_END_RESET_TMP);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
/* Temporarily block writers until we snapshot the meta pages */
rc = mdbx_txn_lock(env, false);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
rc = mdbx_txn_renew0(read_txn, MDBX_RDONLY);
if (unlikely(rc != MDBX_SUCCESS)) {
mdbx_txn_unlock(env);
return rc;
}
/* Make a snapshot of meta-pages,
* but writing ones after the data was flushed */
memcpy(buffer, env->me_map, pgno2bytes(env, NUM_METAS));
MDBX_meta *const headcopy = /* LY: get pointer to the spanshot copy */
(MDBX_meta *)(buffer + ((uint8_t *)mdbx_meta_head(env) - env->me_map));
const uint64_t size =
mdbx_roundup2(pgno2bytes(env, headcopy->mm_geo.now), env->me_os_psize);
mdbx_txn_unlock(env);
/* Update signature to steady */
headcopy->mm_datasync_sign = mdbx_meta_sign(headcopy);
/* Copy the data */
rc = mdbx_pwrite(fd, env->me_map + pgno2bytes(env, NUM_METAS),
pgno2bytes(env, read_txn->mt_next_pgno - NUM_METAS),
pgno2bytes(env, NUM_METAS));
if (likely(rc == MDBX_SUCCESS))
rc = mdbx_ftruncate(fd, size);
return rc;
}
int __cold mdbx_env_copy2fd(MDBX_env *env, mdbx_filehandle_t fd,
unsigned flags) {
if (unlikely(!env))
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
int rc = mdbx_fseek(fd, 0);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
const size_t buffer_size = pgno2bytes(env, NUM_METAS) +
((flags & MDBX_CP_COMPACT) ? MDBX_WBUF * 2 : 0);
uint8_t *buffer = NULL;
rc = mdbx_memalign_alloc(env->me_os_psize, buffer_size, (void **)&buffer);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
MDBX_txn *read_txn = NULL;
/* Do the lock/unlock of the reader mutex before starting the
* write txn. Otherwise other read txns could block writers. */
rc = mdbx_txn_begin(env, NULL, MDBX_RDONLY, &read_txn);
if (unlikely(rc != MDBX_SUCCESS)) {
mdbx_memalign_free(buffer);
return rc;
}
/* Firstly write a stub to meta-pages.
* Now we sure to incomplete copy will not be used. */
memset(buffer, -1, pgno2bytes(env, NUM_METAS));
rc = mdbx_write(fd, buffer, pgno2bytes(env, NUM_METAS));
if (likely(rc == MDBX_SUCCESS)) {
memset(buffer, 0, pgno2bytes(env, NUM_METAS));
rc = (flags & MDBX_CP_COMPACT)
? mdbx_env_compact(env, read_txn, fd, buffer)
: mdbx_env_copy_asis(env, read_txn, fd, buffer);
}
mdbx_txn_abort(read_txn);
if (likely(rc == MDBX_SUCCESS))
rc = mdbx_filesync(fd, true);
/* Write actual meta */
if (likely(rc == MDBX_SUCCESS))
rc = mdbx_pwrite(fd, buffer, pgno2bytes(env, NUM_METAS), 0);
mdbx_memalign_free(buffer);
return rc;
}
int __cold mdbx_env_copy(MDBX_env *env, const char *dest_path, unsigned flags) {
if (unlikely(!env || !dest_path))
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
char *dxb_pathname;
mdbx_filehandle_t newfd = INVALID_HANDLE_VALUE;
if (env->me_flags & MDBX_NOSUBDIR) {
dxb_pathname = (char *)dest_path;
} else {
size_t len = strlen(dest_path);
len += sizeof(MDBX_DATANAME);
dxb_pathname = mdbx_malloc(len);
if (!dxb_pathname)
return MDBX_ENOMEM;
sprintf(dxb_pathname, "%s" MDBX_DATANAME, dest_path);
}
/* The destination path must exist, but the destination file must not.
* We don't want the OS to cache the writes, since the source data is
* already in the OS cache. */
int rc = mdbx_openfile(dxb_pathname, O_WRONLY | O_CREAT | O_EXCL, 0640,
&newfd, true);
if (rc == MDBX_SUCCESS) {
if (env->me_psize >= env->me_os_psize) {
#ifdef F_NOCACHE /* __APPLE__ */
(void)fcntl(newfd, F_NOCACHE, 1);
#elif defined(O_DIRECT) && defined(F_GETFL)
/* Set O_DIRECT if the file system supports it */
if ((rc = fcntl(newfd, F_GETFL)) != -1)
(void)fcntl(newfd, F_SETFL, rc | O_DIRECT);
#endif
}
rc = mdbx_env_copy2fd(env, newfd, flags);
}
if (newfd != INVALID_HANDLE_VALUE) {
int err = mdbx_closefile(newfd);
if (rc == MDBX_SUCCESS && err != rc)
rc = err;
if (rc != MDBX_SUCCESS)
(void)mdbx_removefile(dxb_pathname);
}
if (dxb_pathname != dest_path)
mdbx_free(dxb_pathname);
return rc;
}
int __cold mdbx_env_set_flags(MDBX_env *env, unsigned flags, int onoff) {
if (unlikely(flags & ~CHANGEABLE))
return MDBX_EINVAL;
int rc = mdbx_txn_lock(env, false);
if (unlikely(rc))
return rc;
if (onoff)
env->me_flags |= flags;
else
env->me_flags &= ~flags;
mdbx_txn_unlock(env);
return MDBX_SUCCESS;
}
int __cold mdbx_env_get_flags(MDBX_env *env, unsigned *arg) {
if (unlikely(!env || !arg))
return MDBX_EINVAL;
*arg = env->me_flags & (CHANGEABLE | CHANGELESS);
return MDBX_SUCCESS;
}
int __cold mdbx_env_set_userctx(MDBX_env *env, void *ctx) {
if (unlikely(!env))
return MDBX_EINVAL;
env->me_userctx = ctx;
return MDBX_SUCCESS;
}
void *__cold mdbx_env_get_userctx(MDBX_env *env) {
return env ? env->me_userctx : NULL;
}
int __cold mdbx_env_set_assert(MDBX_env *env, MDBX_assert_func *func) {
if (unlikely(!env))
return MDBX_EINVAL;
#if MDBX_DEBUG
env->me_assert_func = func;
return MDBX_SUCCESS;
#else
(void)func;
return MDBX_ENOSYS;
#endif
}
int __cold mdbx_env_get_path(MDBX_env *env, const char **arg) {
if (unlikely(!env || !arg))
return MDBX_EINVAL;
*arg = env->me_path;
return MDBX_SUCCESS;
}
int __cold mdbx_env_get_fd(MDBX_env *env, mdbx_filehandle_t *arg) {
if (unlikely(!env || !arg))
return MDBX_EINVAL;
*arg = env->me_fd;
return MDBX_SUCCESS;
}
/* Common code for mdbx_dbi_stat() and mdbx_env_stat().
* [in] env the environment to operate in.
* [in] db the MDBX_db record containing the stats to return.
* [out] arg the address of an MDBX_stat structure to receive the stats.
* Returns 0, this function always succeeds. */
static int __cold mdbx_stat0(MDBX_env *env, MDBX_db *db, MDBX_stat *arg) {
arg->ms_psize = env->me_psize;
arg->ms_depth = db->md_depth;
arg->ms_branch_pages = db->md_branch_pages;
arg->ms_leaf_pages = db->md_leaf_pages;
arg->ms_overflow_pages = db->md_overflow_pages;
arg->ms_entries = db->md_entries;
return MDBX_SUCCESS;
}
int __cold mdbx_env_stat(MDBX_env *env, MDBX_stat *arg, size_t bytes) {
MDBX_meta *meta;
if (unlikely(env == NULL || arg == NULL))
return MDBX_EINVAL;
if (unlikely(bytes != sizeof(MDBX_stat)))
return MDBX_EINVAL;
meta = mdbx_meta_head(env);
return mdbx_stat0(env, &meta->mm_dbs[MAIN_DBI], arg);
}
int __cold mdbx_env_info(MDBX_env *env, MDBX_envinfo *arg, size_t bytes) {
if (unlikely(env == NULL || arg == NULL))
return MDBX_EINVAL;
if (bytes != sizeof(MDBX_envinfo))
return MDBX_EINVAL;
const MDBX_meta *const meta0 = METAPAGE(env, 0);
const MDBX_meta *const meta1 = METAPAGE(env, 1);
const MDBX_meta *const meta2 = METAPAGE(env, 2);
const MDBX_meta *meta;
do {
meta = mdbx_meta_head(env);
arg->mi_recent_txnid = mdbx_meta_txnid_fluid(env, meta);
arg->mi_meta0_txnid = mdbx_meta_txnid_fluid(env, meta0);
arg->mi_meta0_sign = meta0->mm_datasync_sign;
arg->mi_meta1_txnid = mdbx_meta_txnid_fluid(env, meta1);
arg->mi_meta1_sign = meta1->mm_datasync_sign;
arg->mi_meta2_txnid = mdbx_meta_txnid_fluid(env, meta2);
arg->mi_meta2_sign = meta2->mm_datasync_sign;
arg->mi_last_pgno = meta->mm_geo.next - 1;
arg->mi_geo.lower = pgno2bytes(env, meta->mm_geo.lower);
arg->mi_geo.upper = pgno2bytes(env, meta->mm_geo.upper);
arg->mi_geo.current = pgno2bytes(env, meta->mm_geo.now);
arg->mi_geo.shrink = pgno2bytes(env, meta->mm_geo.shrink);
arg->mi_geo.grow = pgno2bytes(env, meta->mm_geo.grow);
arg->mi_mapsize = env->me_mapsize;
mdbx_compiler_barrier();
} while (unlikely(arg->mi_meta0_txnid != mdbx_meta_txnid_fluid(env, meta0) ||
arg->mi_meta0_sign != meta0->mm_datasync_sign ||
arg->mi_meta1_txnid != mdbx_meta_txnid_fluid(env, meta1) ||
arg->mi_meta1_sign != meta1->mm_datasync_sign ||
arg->mi_meta2_txnid != mdbx_meta_txnid_fluid(env, meta2) ||
arg->mi_meta2_sign != meta2->mm_datasync_sign ||
meta != mdbx_meta_head(env) ||
arg->mi_recent_txnid != mdbx_meta_txnid_fluid(env, meta)));
arg->mi_maxreaders = env->me_maxreaders;
arg->mi_numreaders = env->me_lck ? env->me_lck->mti_numreaders : INT32_MAX;
arg->mi_dxb_pagesize = env->me_psize;
arg->mi_sys_pagesize = env->me_os_psize;
arg->mi_self_latter_reader_txnid = arg->mi_latter_reader_txnid = 0;
if (env->me_lck) {
MDBX_reader *r = env->me_lck->mti_readers;
arg->mi_self_latter_reader_txnid = arg->mi_latter_reader_txnid =
arg->mi_recent_txnid;
for (unsigned i = 0; i < arg->mi_numreaders; ++i) {
const mdbx_pid_t pid = r[i].mr_pid;
if (pid) {
const txnid_t txnid = r[i].mr_txnid;
if (arg->mi_latter_reader_txnid > txnid)
arg->mi_latter_reader_txnid = txnid;
if (pid == env->me_pid && arg->mi_self_latter_reader_txnid > txnid)
arg->mi_self_latter_reader_txnid = txnid;
}
}
}
return MDBX_SUCCESS;
}
static MDBX_cmp_func *mdbx_default_keycmp(unsigned flags) {
return (flags & MDBX_REVERSEKEY)
? mdbx_cmp_memnr
: (flags & MDBX_INTEGERKEY) ? mdbx_cmp_int_a2 : mdbx_cmp_memn;
}
static MDBX_cmp_func *mdbx_default_datacmp(unsigned flags) {
return !(flags & MDBX_DUPSORT)
? mdbx_cmp_memn
: ((flags & MDBX_INTEGERDUP)
? mdbx_cmp_int_ua
: ((flags & MDBX_REVERSEDUP) ? mdbx_cmp_memnr
: mdbx_cmp_memn));
}
static int mdbx_dbi_bind(MDBX_txn *txn, const MDBX_dbi dbi, unsigned user_flags,
MDBX_cmp_func *keycmp, MDBX_cmp_func *datacmp) {
/* LY: so, accepting only three cases for the table's flags:
* 1) user_flags and both comparators are zero
* = assume that a by-default mode/flags is requested for reading;
* 2) user_flags exactly the same
* = assume that the target mode/flags are requested properly;
* 3) user_flags differs, but table is empty and MDBX_CREATE is provided
* = assume that a properly create request with custom flags;
*/
if ((user_flags ^ txn->mt_dbs[dbi].md_flags) & PERSISTENT_FLAGS) {
/* flags ara differs, check other conditions */
if (!user_flags && (!keycmp || keycmp == txn->mt_dbxs[dbi].md_cmp) &&
(!datacmp || datacmp == txn->mt_dbxs[dbi].md_dcmp)) {
/* no comparators were provided and flags are zero,
* seems that is case #1 above */
user_flags = txn->mt_dbs[dbi].md_flags;
} else if ((user_flags & MDBX_CREATE) && txn->mt_dbs[dbi].md_entries == 0) {
if (txn->mt_flags & MDBX_TXN_RDONLY)
return /* FIXME: return extended info */ MDBX_EACCESS;
/* make sure flags changes get committed */
txn->mt_dbs[dbi].md_flags = user_flags & PERSISTENT_FLAGS;
txn->mt_flags |= MDBX_TXN_DIRTY;
} else {
return /* FIXME: return extended info */ MDBX_INCOMPATIBLE;
}
}
if (!txn->mt_dbxs[dbi].md_cmp || MDBX_DEBUG) {
if (!keycmp)
keycmp = mdbx_default_keycmp(user_flags);
mdbx_tassert(txn, !txn->mt_dbxs[dbi].md_cmp ||
txn->mt_dbxs[dbi].md_cmp == keycmp);
txn->mt_dbxs[dbi].md_cmp = keycmp;
}
if (!txn->mt_dbxs[dbi].md_dcmp || MDBX_DEBUG) {
if (!datacmp)
datacmp = mdbx_default_datacmp(user_flags);
mdbx_tassert(txn, !txn->mt_dbxs[dbi].md_dcmp ||
txn->mt_dbxs[dbi].md_dcmp == datacmp);
txn->mt_dbxs[dbi].md_dcmp = datacmp;
}
return MDBX_SUCCESS;
}
int mdbx_dbi_open_ex(MDBX_txn *txn, const char *table_name, unsigned user_flags,
MDBX_dbi *dbi, MDBX_cmp_func *keycmp,
MDBX_cmp_func *datacmp) {
if (unlikely(!txn || !dbi || (user_flags & ~VALID_FLAGS) != 0))
return MDBX_EINVAL;
switch (user_flags &
(MDBX_INTEGERDUP | MDBX_DUPFIXED | MDBX_DUPSORT | MDBX_REVERSEDUP)) {
default:
return MDBX_EINVAL;
case MDBX_DUPSORT:
case MDBX_DUPSORT | MDBX_REVERSEDUP:
case MDBX_DUPSORT | MDBX_DUPFIXED:
case MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_REVERSEDUP:
case MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_INTEGERDUP:
case MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_INTEGERDUP | MDBX_REVERSEDUP:
case 0:
break;
}
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
/* main table? */
if (!table_name) {
*dbi = MAIN_DBI;
return mdbx_dbi_bind(txn, MAIN_DBI, user_flags, keycmp, datacmp);
}
if (txn->mt_dbxs[MAIN_DBI].md_cmp == NULL) {
txn->mt_dbxs[MAIN_DBI].md_cmp =
mdbx_default_keycmp(txn->mt_dbs[MAIN_DBI].md_flags);
txn->mt_dbxs[MAIN_DBI].md_dcmp =
mdbx_default_datacmp(txn->mt_dbs[MAIN_DBI].md_flags);
}
/* Is the DB already open? */
size_t len = strlen(table_name);
MDBX_dbi scan, slot;
for (slot = scan = txn->mt_numdbs; --scan >= CORE_DBS;) {
if (!txn->mt_dbxs[scan].md_name.iov_len) {
/* Remember this free slot */
slot = scan;
continue;
}
if (len == txn->mt_dbxs[scan].md_name.iov_len &&
!strncmp(table_name, txn->mt_dbxs[scan].md_name.iov_base, len)) {
*dbi = scan;
return mdbx_dbi_bind(txn, scan, user_flags, keycmp, datacmp);
}
}
/* Fail, if no free slot and max hit */
MDBX_env *env = txn->mt_env;
if (unlikely(slot >= env->me_maxdbs))
return MDBX_DBS_FULL;
/* Cannot mix named table with some main-table flags */
if (unlikely(txn->mt_dbs[MAIN_DBI].md_flags &
(MDBX_DUPSORT | MDBX_INTEGERKEY)))
return (user_flags & MDBX_CREATE) ? MDBX_INCOMPATIBLE : MDBX_NOTFOUND;
/* Find the DB info */
int exact = 0;
MDBX_val key, data;
key.iov_len = len;
key.iov_base = (void *)table_name;
MDBX_cursor mc;
int rc = mdbx_cursor_init(&mc, txn, MAIN_DBI);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
rc = mdbx_cursor_set(&mc, &key, &data, MDBX_SET, &exact);
if (unlikely(rc != MDBX_SUCCESS)) {
if (rc != MDBX_NOTFOUND || !(user_flags & MDBX_CREATE))
return rc;
} else {
/* make sure this is actually a table */
MDBX_node *node = NODEPTR(mc.mc_pg[mc.mc_top], mc.mc_ki[mc.mc_top]);
if (unlikely((node->mn_flags & (F_DUPDATA | F_SUBDATA)) != F_SUBDATA))
return MDBX_INCOMPATIBLE;
}
if (rc != MDBX_SUCCESS && unlikely(txn->mt_flags & MDBX_TXN_RDONLY))
return MDBX_EACCESS;
/* Done here so we cannot fail after creating a new DB */
char *namedup = mdbx_strdup(table_name);
if (unlikely(!namedup))
return MDBX_ENOMEM;
int err = mdbx_fastmutex_acquire(&env->me_dbi_lock);
if (unlikely(err != MDBX_SUCCESS)) {
mdbx_free(namedup);
return err;
}
if (txn->mt_numdbs < env->me_numdbs) {
for (unsigned i = txn->mt_numdbs; i < env->me_numdbs; ++i) {
txn->mt_dbflags[i] = 0;
if (env->me_dbflags[i] & MDBX_VALID) {
txn->mt_dbs[i].md_flags = env->me_dbflags[i] & PERSISTENT_FLAGS;
txn->mt_dbflags[i] = DB_VALID | DB_USRVALID | DB_STALE;
mdbx_tassert(txn, txn->mt_dbxs[i].md_cmp != NULL);
}
}
txn->mt_numdbs = env->me_numdbs;
}
for (slot = scan = txn->mt_numdbs; --scan >= CORE_DBS;) {
if (!txn->mt_dbxs[scan].md_name.iov_len) {
/* Remember this free slot */
slot = scan;
continue;
}
if (len == txn->mt_dbxs[scan].md_name.iov_len &&
!strncmp(table_name, txn->mt_dbxs[scan].md_name.iov_base, len)) {
*dbi = scan;
rc = mdbx_dbi_bind(txn, scan, user_flags, keycmp, datacmp);
goto bailout;
}
}
if (unlikely(slot >= env->me_maxdbs)) {
rc = MDBX_DBS_FULL;
goto bailout;
}
unsigned dbflag = DB_FRESH | DB_VALID | DB_USRVALID;
MDBX_db db_dummy;
if (unlikely(rc)) {
/* MDBX_NOTFOUND and MDBX_CREATE: Create new DB */
mdbx_tassert(txn, rc == MDBX_NOTFOUND);
memset(&db_dummy, 0, sizeof(db_dummy));
db_dummy.md_root = P_INVALID;
db_dummy.md_flags = user_flags & PERSISTENT_FLAGS;
data.iov_len = sizeof(db_dummy);
data.iov_base = &db_dummy;
WITH_CURSOR_TRACKING(
mc,
rc = mdbx_cursor_put(&mc, &key, &data, F_SUBDATA | MDBX_NOOVERWRITE));
if (unlikely(rc != MDBX_SUCCESS))
goto bailout;
dbflag |= DB_DIRTY | DB_CREAT;
}
/* Got info, register DBI in this txn */
txn->mt_dbxs[slot].md_cmp = nullptr;
txn->mt_dbxs[slot].md_dcmp = nullptr;
txn->mt_dbs[slot] = *(MDBX_db *)data.iov_base;
env->me_dbflags[slot] = 0;
rc = mdbx_dbi_bind(txn, slot, user_flags, keycmp, datacmp);
if (unlikely(rc != MDBX_SUCCESS)) {
mdbx_tassert(txn, (dbflag & DB_CREAT) == 0);
bailout:
mdbx_free(namedup);
} else {
txn->mt_dbflags[slot] = (uint8_t)dbflag;
txn->mt_dbxs[slot].md_name.iov_base = namedup;
txn->mt_dbxs[slot].md_name.iov_len = len;
txn->mt_numdbs += (slot == txn->mt_numdbs);
if ((dbflag & DB_CREAT) == 0) {
env->me_dbflags[slot] = txn->mt_dbs[slot].md_flags | MDBX_VALID;
mdbx_compiler_barrier();
if (env->me_numdbs <= slot)
env->me_numdbs = slot + 1;
} else {
env->me_dbiseqs[slot] += 1;
}
txn->mt_dbiseqs[slot] = env->me_dbiseqs[slot];
*dbi = slot;
}
mdbx_ensure(env, mdbx_fastmutex_release(&env->me_dbi_lock) == MDBX_SUCCESS);
return rc;
}
int mdbx_dbi_open(MDBX_txn *txn, const char *table_name, unsigned table_flags,
MDBX_dbi *dbi) {
return mdbx_dbi_open_ex(txn, table_name, table_flags, dbi, nullptr, nullptr);
}
int __cold mdbx_dbi_stat(MDBX_txn *txn, MDBX_dbi dbi, MDBX_stat *arg,
size_t bytes) {
if (unlikely(!arg || !txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_VALID)))
return MDBX_EINVAL;
if (unlikely(bytes != sizeof(MDBX_stat)))
return MDBX_EINVAL;
if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
if (unlikely(txn->mt_dbflags[dbi] & DB_STALE)) {
MDBX_cursor_couple cx;
/* Stale, must read the DB's root. cursor_init does it for us. */
int rc = mdbx_cursor_init(&cx.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
return mdbx_stat0(txn->mt_env, &txn->mt_dbs[dbi], arg);
}
static int mdbx_dbi_close_locked(MDBX_env *env, MDBX_dbi dbi) {
if (unlikely(dbi < CORE_DBS || dbi >= env->me_maxdbs))
return MDBX_EINVAL;
char *ptr = env->me_dbxs[dbi].md_name.iov_base;
/* If there was no name, this was already closed */
if (unlikely(!ptr))
return MDBX_BAD_DBI;
env->me_dbflags[dbi] = 0;
env->me_dbxs[dbi].md_name.iov_len = 0;
mdbx_compiler_barrier();
env->me_dbiseqs[dbi]++;
env->me_dbxs[dbi].md_name.iov_base = NULL;
mdbx_free(ptr);
return MDBX_SUCCESS;
}
int mdbx_dbi_close(MDBX_env *env, MDBX_dbi dbi) {
if (unlikely(dbi < CORE_DBS || dbi >= env->me_maxdbs))
return MDBX_EINVAL;
int rc = mdbx_fastmutex_acquire(&env->me_dbi_lock);
if (likely(rc == MDBX_SUCCESS)) {
rc = mdbx_dbi_close_locked(env, dbi);
mdbx_ensure(env, mdbx_fastmutex_release(&env->me_dbi_lock) == MDBX_SUCCESS);
}
return rc;
}
int mdbx_dbi_flags_ex(MDBX_txn *txn, MDBX_dbi dbi, unsigned *flags,
unsigned *state) {
if (unlikely(!txn || !flags || !state))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_VALID)))
return MDBX_EINVAL;
*flags = txn->mt_dbs[dbi].md_flags & PERSISTENT_FLAGS;
*state = txn->mt_dbflags[dbi] & (DB_FRESH | DB_CREAT | DB_DIRTY | DB_STALE);
return MDBX_SUCCESS;
}
int mdbx_dbi_flags(MDBX_txn *txn, MDBX_dbi dbi, unsigned *flags) {
unsigned state;
return mdbx_dbi_flags_ex(txn, dbi, flags, &state);
}
/* Add all the DB's pages to the free list.
* [in] mc Cursor on the DB to free.
* [in] subs non-Zero to check for sub-DBs in this DB.
* Returns 0 on success, non-zero on failure. */
static int mdbx_drop0(MDBX_cursor *mc, int subs) {
int rc = mdbx_page_search(mc, NULL, MDBX_PS_FIRST);
if (likely(rc == MDBX_SUCCESS)) {
MDBX_txn *txn = mc->mc_txn;
MDBX_node *ni;
MDBX_cursor mx;
unsigned i;
/* DUPSORT sub-DBs have no ovpages/DBs. Omit scanning leaves.
* This also avoids any P_LEAF2 pages, which have no nodes.
* Also if the DB doesn't have sub-DBs and has no overflow
* pages, omit scanning leaves. */
if (mc->mc_flags & C_SUB) {
MDBX_db *outer = mdbx_outer_db(mc);
outer->md_branch_pages -= mc->mc_db->md_branch_pages;
outer->md_leaf_pages -= mc->mc_db->md_leaf_pages;
outer->md_overflow_pages -= mc->mc_db->md_overflow_pages;
mdbx_cursor_pop(mc);
} else if (!subs && !mc->mc_db->md_overflow_pages)
mdbx_cursor_pop(mc);
mdbx_cursor_copy(mc, &mx);
while (mc->mc_snum > 0) {
MDBX_page *mp = mc->mc_pg[mc->mc_top];
unsigned n = NUMKEYS(mp);
if (IS_LEAF(mp)) {
for (i = 0; i < n; i++) {
ni = NODEPTR(mp, i);
if (ni->mn_flags & F_BIGDATA) {
MDBX_page *omp;
pgno_t pg;
memcpy(&pg, NODEDATA(ni), sizeof(pg));
rc = mdbx_page_get(mc, pg, &omp, NULL);
if (unlikely(rc))
goto done;
mdbx_cassert(mc, IS_OVERFLOW(omp));
rc = mdbx_page_befree(mc, omp);
if (unlikely(rc))
goto done;
if (!mc->mc_db->md_overflow_pages && !subs)
break;
} else if (subs && (ni->mn_flags & F_SUBDATA)) {
rc = mdbx_xcursor_init1(mc, ni);
if (unlikely(rc != MDBX_SUCCESS))
goto done;
rc = mdbx_drop0(&mc->mc_xcursor->mx_cursor, 0);
if (unlikely(rc))
goto done;
}
}
if (!subs && !mc->mc_db->md_overflow_pages)
goto pop;
} else {
if (unlikely((rc = mdbx_pnl_need(&txn->mt_befree_pages, n)) != 0))
goto done;
for (i = 0; i < n; i++) {
pgno_t pg;
ni = NODEPTR(mp, i);
pg = NODEPGNO(ni);
/* free it */
mdbx_pnl_xappend(txn->mt_befree_pages, pg);
}
}
if (!mc->mc_top)
break;
mdbx_cassert(mc, i <= UINT16_MAX);
mc->mc_ki[mc->mc_top] = (indx_t)i;
rc = mdbx_cursor_sibling(mc, 1);
if (rc) {
if (unlikely(rc != MDBX_NOTFOUND))
goto done;
/* no more siblings, go back to beginning
* of previous level. */
pop:
mdbx_cursor_pop(mc);
mc->mc_ki[0] = 0;
for (i = 1; i < mc->mc_snum; i++) {
mc->mc_ki[i] = 0;
mc->mc_pg[i] = mx.mc_pg[i];
}
}
}
/* free it */
rc = mdbx_pnl_append(&txn->mt_befree_pages, mc->mc_db->md_root);
done:
if (unlikely(rc))
txn->mt_flags |= MDBX_TXN_ERROR;
} else if (rc == MDBX_NOTFOUND) {
rc = MDBX_SUCCESS;
}
mc->mc_flags &= ~C_INITIALIZED;
return rc;
}
int mdbx_drop(MDBX_txn *txn, MDBX_dbi dbi, int del) {
if (unlikely(1 < (unsigned)del || !txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
if (unlikely(TXN_DBI_CHANGED(txn, dbi)))
return MDBX_BAD_DBI;
if (unlikely(F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY)))
return MDBX_EACCESS;
MDBX_cursor *mc;
int rc = mdbx_cursor_open(txn, dbi, &mc);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
MDBX_env *env = txn->mt_env;
rc = mdbx_fastmutex_acquire(&env->me_dbi_lock);
if (unlikely(rc != MDBX_SUCCESS)) {
mdbx_cursor_close(mc);
return rc;
}
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID))) {
rc = MDBX_EINVAL;
goto bailout;
}
if (unlikely(TXN_DBI_CHANGED(txn, dbi))) {
rc = MDBX_BAD_DBI;
goto bailout;
}
rc = mdbx_drop0(mc, mc->mc_db->md_flags & MDBX_DUPSORT);
/* Invalidate the dropped DB's cursors */
for (MDBX_cursor *m2 = txn->mt_cursors[dbi]; m2; m2 = m2->mc_next)
m2->mc_flags &= ~(C_INITIALIZED | C_EOF);
if (unlikely(rc))
goto bailout;
/* Can't delete the main DB */
if (del && dbi >= CORE_DBS) {
rc = mdbx_del0(txn, MAIN_DBI, &mc->mc_dbx->md_name, NULL, F_SUBDATA);
if (likely(!rc)) {
txn->mt_dbflags[dbi] = DB_STALE;
mdbx_dbi_close_locked(env, dbi);
} else {
txn->mt_flags |= MDBX_TXN_ERROR;
}
} else {
/* reset the DB record, mark it dirty */
txn->mt_dbflags[dbi] |= DB_DIRTY;
txn->mt_dbs[dbi].md_depth = 0;
txn->mt_dbs[dbi].md_branch_pages = 0;
txn->mt_dbs[dbi].md_leaf_pages = 0;
txn->mt_dbs[dbi].md_overflow_pages = 0;
txn->mt_dbs[dbi].md_entries = 0;
txn->mt_dbs[dbi].md_root = P_INVALID;
txn->mt_dbs[dbi].md_seq = 0;
txn->mt_flags |= MDBX_TXN_DIRTY;
}
bailout:
mdbx_cursor_close(mc);
mdbx_ensure(env, mdbx_fastmutex_release(&env->me_dbi_lock) == MDBX_SUCCESS);
return rc;
}
int mdbx_set_compare(MDBX_txn *txn, MDBX_dbi dbi, MDBX_cmp_func *cmp) {
if (unlikely(!txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
txn->mt_dbxs[dbi].md_cmp = cmp;
return MDBX_SUCCESS;
}
int mdbx_set_dupsort(MDBX_txn *txn, MDBX_dbi dbi, MDBX_cmp_func *cmp) {
if (unlikely(!txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
txn->mt_dbxs[dbi].md_dcmp = cmp;
return MDBX_SUCCESS;
}
int __cold mdbx_reader_list(MDBX_env *env, MDBX_msg_func *func, void *ctx) {
char buf[64];
int rc = 0, first = 1;
if (unlikely(!env || !func))
return (MDBX_EINVAL > 0) ? -MDBX_EINVAL : MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
const MDBX_lockinfo *const lck = env->me_lck;
if (likely(lck)) {
const unsigned snap_nreaders = lck->mti_numreaders;
for (unsigned i = 0; i < snap_nreaders; i++) {
if (lck->mti_readers[i].mr_pid) {
const txnid_t txnid = lck->mti_readers[i].mr_txnid;
if (txnid == ~(txnid_t)0)
snprintf(buf, sizeof(buf), "%10" PRIuPTR " %" PRIxPTR " -\n",
(uintptr_t)lck->mti_readers[i].mr_pid,
(uintptr_t)lck->mti_readers[i].mr_tid);
else
snprintf(buf, sizeof(buf),
"%10" PRIuPTR " %" PRIxPTR " %" PRIaTXN "\n",
(uintptr_t)lck->mti_readers[i].mr_pid,
(uintptr_t)lck->mti_readers[i].mr_tid, txnid);
if (first) {
first = 0;
rc = func(" pid thread txnid\n", ctx);
if (rc < 0)
break;
}
rc = func(buf, ctx);
if (rc < 0)
break;
}
}
}
if (first)
rc = func("(no active readers)\n", ctx);
return rc;
}
/* Insert pid into list if not already present.
* return -1 if already present. */
static int __cold mdbx_pid_insert(mdbx_pid_t *ids, mdbx_pid_t pid) {
/* binary search of pid in list */
unsigned base = 0;
unsigned cursor = 1;
int val = 0;
unsigned n = ids[0];
while (n > 0) {
unsigned pivot = n >> 1;
cursor = base + pivot + 1;
val = pid - ids[cursor];
if (val < 0) {
n = pivot;
} else if (val > 0) {
base = cursor;
n -= pivot + 1;
} else {
/* found, so it's a duplicate */
return -1;
}
}
if (val > 0)
++cursor;
ids[0]++;
for (n = ids[0]; n > cursor; n--)
ids[n] = ids[n - 1];
ids[n] = pid;
return 0;
}
int __cold mdbx_reader_check(MDBX_env *env, int *dead) {
if (unlikely(!env || env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EINVAL;
if (dead)
*dead = 0;
return mdbx_reader_check0(env, false, dead);
}
/* Return:
* MDBX_RESULT_TRUE - done and mutex recovered
* MDBX_SUCCESS - done
* Otherwise errcode. */
int __cold mdbx_reader_check0(MDBX_env *env, int rdt_locked, int *dead) {
mdbx_assert(env, rdt_locked >= 0);
if (unlikely(env->me_pid != mdbx_getpid())) {
env->me_flags |= MDBX_FATAL_ERROR;
return MDBX_PANIC;
}
MDBX_lockinfo *const lck = env->me_lck;
if (unlikely(lck == NULL)) {
/* exclusive mode */
if (dead)
*dead = 0;
return MDBX_SUCCESS;
}
const unsigned snap_nreaders = lck->mti_numreaders;
mdbx_pid_t pidsbuf_onstask[142];
mdbx_pid_t *const pids =
(snap_nreaders < ARRAY_LENGTH(pidsbuf_onstask))
? pidsbuf_onstask
: mdbx_malloc((snap_nreaders + 1) * sizeof(mdbx_pid_t));
if (unlikely(!pids))
return MDBX_ENOMEM;
pids[0] = 0;
int rc = MDBX_SUCCESS, count = 0;
for (unsigned i = 0; i < snap_nreaders; i++) {
const mdbx_pid_t pid = lck->mti_readers[i].mr_pid;
if (pid == 0)
continue /* skip empty */;
if (pid == env->me_pid)
continue /* skip self */;
if (mdbx_pid_insert(pids, pid) != 0)
continue /* such pid already processed */;
int err = mdbx_rpid_check(env, pid);
if (err == MDBX_RESULT_TRUE)
continue /* reader is live */;
if (err != MDBX_SUCCESS) {
rc = err;
break /* mdbx_rpid_check() failed */;
}
/* stale reader found */
if (!rdt_locked) {
err = mdbx_rdt_lock(env);
if (MDBX_IS_ERROR(err)) {
rc = err;
break;
}
rdt_locked = -1;
if (err == MDBX_RESULT_TRUE) {
/* mutex recovered, the mdbx_mutex_failed() checked all readers */
rc = MDBX_RESULT_TRUE;
break;
}
/* a other process may have clean and reused slot, recheck */
if (lck->mti_readers[i].mr_pid != pid)
continue;
err = mdbx_rpid_check(env, pid);
if (MDBX_IS_ERROR(err)) {
rc = err;
break;
}
if (err != MDBX_SUCCESS)
continue /* the race with other process, slot reused */;
}
/* clean it */
for (unsigned j = i; j < snap_nreaders; j++) {
if (lck->mti_readers[j].mr_pid == pid) {
mdbx_debug("clear stale reader pid %" PRIuPTR " txn %" PRIaTXN,
(size_t)pid, lck->mti_readers[j].mr_txnid);
lck->mti_readers[j].mr_pid = 0;
lck->mti_readers_refresh_flag = true;
count++;
}
}
}
if (rdt_locked < 0)
mdbx_rdt_unlock(env);
if (pids != pidsbuf_onstask)
mdbx_free(pids);
if (dead)
*dead = count;
return rc;
}
int __cold mdbx_setup_debug(int flags, MDBX_debug_func *logger) {
unsigned ret = mdbx_runtime_flags;
mdbx_runtime_flags = flags;
#ifdef __linux__
if (flags & MDBX_DBG_DUMP) {
int core_filter_fd = open("/proc/self/coredump_filter", O_TRUNC | O_RDWR);
if (core_filter_fd >= 0) {
char buf[32];
const unsigned r = pread(core_filter_fd, buf, sizeof(buf), 0);
if (r > 0 && r < sizeof(buf)) {
buf[r] = 0;
unsigned long mask = strtoul(buf, NULL, 16);
if (mask != ULONG_MAX) {
mask |= 1 << 3 /* Dump file-backed shared mappings */;
mask |= 1 << 6 /* Dump shared huge pages */;
mask |= 1 << 8 /* Dump shared DAX pages */;
unsigned w = snprintf(buf, sizeof(buf), "0x%lx\n", mask);
if (w > 0 && w < sizeof(buf)) {
w = pwrite(core_filter_fd, buf, w, 0);
(void)w;
}
}
}
close(core_filter_fd);
}
}
#endif /* __linux__ */
mdbx_debug_logger = logger;
return ret;
}
static txnid_t __cold mdbx_oomkick(MDBX_env *env, const txnid_t laggard) {
mdbx_debug("DB size maxed out");
int retry;
for (retry = 0; retry < INT_MAX; ++retry) {
txnid_t oldest = mdbx_reclaiming_detent(env);
mdbx_assert(env, oldest < env->me_txn0->mt_txnid);
mdbx_assert(env, oldest >= laggard);
mdbx_assert(env, oldest >= *env->me_oldest);
if (oldest == laggard || unlikely(env->me_lck == NULL /* exclusive mode */))
return oldest;
if (MDBX_IS_ERROR(mdbx_reader_check0(env, false, NULL)))
break;
MDBX_reader *const rtbl = env->me_lck->mti_readers;
MDBX_reader *asleep = nullptr;
for (int i = env->me_lck->mti_numreaders; --i >= 0;) {
if (rtbl[i].mr_pid) {
mdbx_jitter4testing(true);
const txnid_t snap = rtbl[i].mr_txnid;
if (oldest > snap && laggard <= /* ignore pending updates */ snap) {
oldest = snap;
asleep = &rtbl[i];
}
}
}
if (laggard < oldest || !asleep) {
if (retry && env->me_oom_func) {
/* LY: notify end of oom-loop */
const txnid_t gap = oldest - laggard;
env->me_oom_func(env, 0, 0, laggard,
(gap < UINT_MAX) ? (unsigned)gap : UINT_MAX, -retry);
}
mdbx_notice("oom-kick: update oldest %" PRIaTXN " -> %" PRIaTXN,
*env->me_oldest, oldest);
mdbx_assert(env, *env->me_oldest <= oldest);
return *env->me_oldest = oldest;
}
mdbx_tid_t tid;
mdbx_pid_t pid;
int rc;
if (!env->me_oom_func)
break;
pid = asleep->mr_pid;
tid = asleep->mr_tid;
if (asleep->mr_txnid != laggard || pid <= 0)
continue;
const txnid_t gap =
mdbx_meta_txnid_stable(env, mdbx_meta_head(env)) - laggard;
rc = env->me_oom_func(env, pid, tid, laggard,
(gap < UINT_MAX) ? (unsigned)gap : UINT_MAX, retry);
if (rc < 0)
break;
if (rc) {
asleep->mr_txnid = ~(txnid_t)0;
env->me_lck->mti_readers_refresh_flag = true;
if (rc > 1) {
asleep->mr_tid = 0;
asleep->mr_pid = 0;
mdbx_coherent_barrier();
}
}
}
if (retry && env->me_oom_func) {
/* LY: notify end of oom-loop */
env->me_oom_func(env, 0, 0, laggard, 0, -retry);
}
return mdbx_find_oldest(env->me_txn);
}
int __cold mdbx_env_set_syncbytes(MDBX_env *env, size_t bytes) {
if (unlikely(!env))
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
env->me_sync_threshold = bytes;
return env->me_map ? mdbx_env_sync(env, false) : MDBX_SUCCESS;
}
int __cold mdbx_env_set_oomfunc(MDBX_env *env, MDBX_oom_func *oomfunc) {
if (unlikely(!env))
return MDBX_EINVAL;
if (unlikely(env->me_signature != MDBX_ME_SIGNATURE))
return MDBX_EBADSIGN;
env->me_oom_func = oomfunc;
return MDBX_SUCCESS;
}
MDBX_oom_func *__cold mdbx_env_get_oomfunc(MDBX_env *env) {
return likely(env && env->me_signature == MDBX_ME_SIGNATURE)
? env->me_oom_func
: NULL;
}
#ifdef __SANITIZE_THREAD__
/* LY: avoid tsan-trap by me_txn, mm_last_pg and mt_next_pgno */
__attribute__((no_sanitize_thread, noinline))
#endif
int mdbx_txn_straggler(MDBX_txn *txn, int *percent)
{
if (unlikely(!txn))
return (MDBX_EINVAL > 0) ? -MDBX_EINVAL : MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
MDBX_env *env = txn->mt_env;
if (unlikely((txn->mt_flags & MDBX_RDONLY) == 0)) {
if (percent)
*percent =
(int)((txn->mt_next_pgno * UINT64_C(100) + txn->mt_end_pgno / 2) /
txn->mt_end_pgno);
return 0;
}
txnid_t recent;
MDBX_meta *meta;
do {
meta = mdbx_meta_head(env);
recent = mdbx_meta_txnid_fluid(env, meta);
if (percent) {
const pgno_t maxpg = meta->mm_geo.now;
*percent = (int)((meta->mm_geo.next * UINT64_C(100) + maxpg / 2) / maxpg);
}
} while (unlikely(recent != mdbx_meta_txnid_fluid(env, meta)));
txnid_t lag = recent - txn->mt_ro_reader->mr_txnid;
return (lag > INT_MAX) ? INT_MAX : (int)lag;
}
typedef struct mdbx_walk_ctx {
MDBX_txn *mw_txn;
void *mw_user;
MDBX_pgvisitor_func *mw_visitor;
} mdbx_walk_ctx_t;
/* Depth-first tree traversal. */
static int __cold mdbx_env_walk(mdbx_walk_ctx_t *ctx, const char *dbi,
pgno_t pgno, int deep) {
if (pgno == P_INVALID)
return MDBX_SUCCESS; /* empty db */
MDBX_cursor mc;
memset(&mc, 0, sizeof(mc));
mc.mc_snum = 1;
mc.mc_txn = ctx->mw_txn;
MDBX_page *mp;
int rc = mdbx_page_get(&mc, pgno, &mp, NULL);
if (rc)
return rc;
const int nkeys = NUMKEYS(mp);
size_t header_size = IS_LEAF2(mp) ? PAGEHDRSZ : PAGEHDRSZ + mp->mp_lower;
size_t unused_size = SIZELEFT(mp);
size_t payload_size = 0;
size_t align_bytes = 0;
MDBX_page_type_t type;
/* LY: Don't use mask here, e.g bitwise
* (P_BRANCH|P_LEAF|P_LEAF2|P_META|P_OVERFLOW|P_SUBP).
* Pages should not me marked dirty/loose or otherwise. */
switch (mp->mp_flags) {
case P_BRANCH:
type = MDBX_page_branch;
if (nkeys < 2)
return MDBX_CORRUPTED;
break;
case P_LEAF:
type = MDBX_page_leaf;
break;
case P_LEAF | P_LEAF2:
type = MDBX_page_dupfixed_leaf;
break;
default:
return MDBX_CORRUPTED;
}
for (int i = 0; i < nkeys;
align_bytes += ((payload_size + align_bytes) & 1), i++) {
if (type == MDBX_page_dupfixed_leaf) {
/* LEAF2 pages have no mp_ptrs[] or node headers */
payload_size += mp->mp_leaf2_ksize;
continue;
}
MDBX_node *node = NODEPTR(mp, i);
payload_size += NODESIZE + NODEKSZ(node);
if (type == MDBX_page_branch) {
rc = mdbx_env_walk(ctx, dbi, NODEPGNO(node), deep);
if (rc)
return rc;
continue;
}
assert(type == MDBX_page_leaf);
switch (node->mn_flags) {
case 0 /* usual node */: {
payload_size += NODEDSZ(node);
} break;
case F_BIGDATA /* long data on the large/overflow page */: {
payload_size += sizeof(pgno_t);
MDBX_page *op;
pgno_t large_pgno;
memcpy(&large_pgno, NODEDATA(node), sizeof(pgno_t));
rc = mdbx_page_get(&mc, large_pgno, &op, NULL);
if (rc)
return rc;
/* LY: Don't use mask here, e.g bitwise
* (P_BRANCH|P_LEAF|P_LEAF2|P_META|P_OVERFLOW|P_SUBP).
* Pages should not me marked dirty/loose or otherwise. */
if (P_OVERFLOW != op->mp_flags)
return MDBX_CORRUPTED;
const size_t over_header = PAGEHDRSZ;
const size_t over_payload = NODEDSZ(node);
const size_t over_unused = pgno2bytes(ctx->mw_txn->mt_env, op->mp_pages) -
over_payload - over_header;
rc = ctx->mw_visitor(large_pgno, op->mp_pages, ctx->mw_user, deep, dbi,
pgno2bytes(ctx->mw_txn->mt_env, op->mp_pages),
MDBX_page_large, 1, over_payload, over_header,
over_unused);
} break;
case F_SUBDATA /* sub-db */: {
const size_t namelen = NODEKSZ(node);
if (namelen == 0 || NODEDSZ(node) != sizeof(MDBX_db))
return MDBX_CORRUPTED;
payload_size += sizeof(MDBX_db);
MDBX_db db;
memcpy(&db, NODEDATA(node), sizeof(db));
char namebuf_onstask[142];
char *const name = (namelen < sizeof(namebuf_onstask))
? namebuf_onstask
: mdbx_malloc(namelen + 1);
if (name) {
memcpy(name, NODEKEY(node), namelen);
name[namelen] = 0;
rc = mdbx_env_walk(ctx, name, db.md_root, deep + 1);
if (name != namebuf_onstask)
mdbx_free(name);
} else {
rc = MDBX_ENOMEM;
}
} break;
case F_SUBDATA | F_DUPDATA /* dupsorted sub-tree */: {
if (NODEDSZ(node) != sizeof(MDBX_db))
return MDBX_CORRUPTED;
payload_size += sizeof(MDBX_db);
MDBX_db db;
memcpy(&db, NODEDATA(node), sizeof(db));
rc = mdbx_env_walk(ctx, dbi, db.md_root, deep + 1);
} break;
case F_DUPDATA /* short sub-page */: {
if (NODEDSZ(node) < PAGEHDRSZ)
return MDBX_CORRUPTED;
MDBX_page *sp = NODEDATA(node);
const int nsubkeys = NUMKEYS(sp);
size_t subheader_size =
IS_LEAF2(sp) ? PAGEHDRSZ : PAGEHDRSZ + sp->mp_lower;
size_t subunused_size = SIZELEFT(sp);
size_t subpayload_size = 0;
size_t subalign_bytes = 0;
MDBX_page_type_t subtype;
switch (sp->mp_flags & ~P_DIRTY /* ignore for sub-pages */) {
case P_LEAF | P_SUBP:
subtype = MDBX_subpage_leaf;
break;
case P_LEAF | P_LEAF2 | P_SUBP:
subtype = MDBX_subpage_dupfixed_leaf;
break;
default:
return MDBX_CORRUPTED;
}
for (int j = 0; j < nsubkeys;
subalign_bytes += ((subpayload_size + subalign_bytes) & 1), j++) {
if (subtype == MDBX_subpage_dupfixed_leaf) {
/* LEAF2 pages have no mp_ptrs[] or node headers */
subpayload_size += sp->mp_leaf2_ksize;
} else {
assert(subtype == MDBX_subpage_leaf);
MDBX_node *subnode = NODEPTR(sp, j);
subpayload_size += NODESIZE + NODEKSZ(subnode) + NODEDSZ(subnode);
if (subnode->mn_flags != 0)
return MDBX_CORRUPTED;
}
}
rc = ctx->mw_visitor(pgno, 0, ctx->mw_user, deep + 1, dbi, NODEDSZ(node),
subtype, nsubkeys, subpayload_size, subheader_size,
subunused_size + subalign_bytes);
header_size += subheader_size;
unused_size += subunused_size;
payload_size += subpayload_size;
align_bytes += subalign_bytes;
} break;
default:
return MDBX_CORRUPTED;
}
if (unlikely(rc))
return rc;
}
return ctx->mw_visitor(mp->mp_pgno, 1, ctx->mw_user, deep, dbi,
ctx->mw_txn->mt_env->me_psize, type, nkeys,
payload_size, header_size, unused_size + align_bytes);
}
int __cold mdbx_env_pgwalk(MDBX_txn *txn, MDBX_pgvisitor_func *visitor,
void *user) {
if (unlikely(!txn))
return MDBX_BAD_TXN;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
mdbx_walk_ctx_t ctx;
ctx.mw_txn = txn;
ctx.mw_user = user;
ctx.mw_visitor = visitor;
int rc = visitor(
0, NUM_METAS, user, -2, "@META", pgno2bytes(txn->mt_env, NUM_METAS),
MDBX_page_meta, NUM_METAS, sizeof(MDBX_meta) * NUM_METAS,
PAGEHDRSZ * NUM_METAS,
(txn->mt_env->me_psize - sizeof(MDBX_meta) - PAGEHDRSZ) * NUM_METAS);
if (!rc)
rc = mdbx_env_walk(&ctx, "@GC", txn->mt_dbs[FREE_DBI].md_root, -1);
if (!rc)
rc = mdbx_env_walk(&ctx, "@MAIN", txn->mt_dbs[MAIN_DBI].md_root, 0);
if (!rc)
rc = visitor(P_INVALID, 0, user, INT_MIN, NULL, 0, MDBX_page_void, 0, 0, 0,
0);
return rc;
}
int mdbx_canary_put(MDBX_txn *txn, const mdbx_canary *canary) {
if (unlikely(!txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
if (unlikely(F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY)))
return MDBX_EACCESS;
if (likely(canary)) {
if (txn->mt_canary.x == canary->x && txn->mt_canary.y == canary->y &&
txn->mt_canary.z == canary->z)
return MDBX_SUCCESS;
txn->mt_canary.x = canary->x;
txn->mt_canary.y = canary->y;
txn->mt_canary.z = canary->z;
}
txn->mt_canary.v = txn->mt_txnid;
if ((txn->mt_flags & MDBX_TXN_DIRTY) == 0) {
MDBX_env *env = txn->mt_env;
txn->mt_flags |= MDBX_TXN_DIRTY;
env->me_sync_pending += env->me_psize;
}
return MDBX_SUCCESS;
}
int mdbx_canary_get(MDBX_txn *txn, mdbx_canary *canary) {
if (unlikely(txn == NULL || canary == NULL))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
*canary = txn->mt_canary;
return MDBX_SUCCESS;
}
int mdbx_cursor_on_first(MDBX_cursor *mc) {
if (unlikely(mc == NULL))
return MDBX_EINVAL;
if (unlikely(mc->mc_signature != MDBX_MC_SIGNATURE))
return MDBX_EBADSIGN;
if (!(mc->mc_flags & C_INITIALIZED))
return MDBX_RESULT_FALSE;
for (unsigned i = 0; i < mc->mc_snum; ++i) {
if (mc->mc_ki[i])
return MDBX_RESULT_FALSE;
}
return MDBX_RESULT_TRUE;
}
int mdbx_cursor_on_last(MDBX_cursor *mc) {
if (unlikely(mc == NULL))
return MDBX_EINVAL;
if (unlikely(mc->mc_signature != MDBX_MC_SIGNATURE))
return MDBX_EBADSIGN;
if (!(mc->mc_flags & C_INITIALIZED))
return MDBX_RESULT_FALSE;
for (unsigned i = 0; i < mc->mc_snum; ++i) {
unsigned nkeys = NUMKEYS(mc->mc_pg[i]);
if (mc->mc_ki[i] < nkeys - 1)
return MDBX_RESULT_FALSE;
}
return MDBX_RESULT_TRUE;
}
int mdbx_cursor_eof(MDBX_cursor *mc) {
if (unlikely(mc == NULL))
return MDBX_EINVAL;
if (unlikely(mc->mc_signature != MDBX_MC_SIGNATURE))
return MDBX_EBADSIGN;
if ((mc->mc_flags & C_INITIALIZED) == 0)
return MDBX_RESULT_TRUE;
if (mc->mc_snum == 0)
return MDBX_RESULT_TRUE;
if ((mc->mc_flags & C_EOF) &&
mc->mc_ki[mc->mc_top] >= NUMKEYS(mc->mc_pg[mc->mc_top]))
return MDBX_RESULT_TRUE;
return MDBX_RESULT_FALSE;
}
//------------------------------------------------------------------------------
struct diff_result {
ptrdiff_t diff;
int level;
int root_nkeys;
};
/* calculates: r = x - y */
__hot static int cursor_diff(const MDBX_cursor *const __restrict x,
const MDBX_cursor *const __restrict y,
struct diff_result *const __restrict r) {
r->diff = 0;
r->level = 0;
r->root_nkeys = 0;
if (unlikely(y->mc_signature != MDBX_MC_SIGNATURE ||
x->mc_signature != MDBX_MC_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(y->mc_dbi != x->mc_dbi))
return MDBX_EINVAL;
if (unlikely(!(y->mc_flags & x->mc_flags & C_INITIALIZED)))
return MDBX_ENODATA;
while (likely(r->level < y->mc_snum && r->level < x->mc_snum)) {
if (unlikely(y->mc_pg[r->level] != x->mc_pg[r->level]))
return MDBX_PROBLEM;
int nkeys = NUMKEYS(y->mc_pg[r->level]);
assert(nkeys > 0);
if (r->level == 0)
r->root_nkeys = nkeys;
const int limit_ki = nkeys - 1;
const int x_ki = x->mc_ki[r->level];
const int y_ki = y->mc_ki[r->level];
r->diff = ((x_ki < limit_ki) ? x_ki : limit_ki) -
((y_ki < limit_ki) ? y_ki : limit_ki);
if (r->diff == 0) {
r->level += 1;
continue;
}
while (unlikely(r->diff == 1) &&
likely(r->level + 1 < y->mc_snum && r->level + 1 < x->mc_snum)) {
r->level += 1;
/* DB'PAGEs: 0------------------>MAX
*
* CURSORs: y < x
* STACK[i ]: |
* STACK[+1]: ...y++N|0++x...
*/
nkeys = NUMKEYS(y->mc_pg[r->level]);
r->diff = (nkeys - y->mc_ki[r->level]) + x->mc_ki[r->level];
assert(r->diff > 0);
}
while (unlikely(r->diff == -1) &&
likely(r->level + 1 < y->mc_snum && r->level + 1 < x->mc_snum)) {
r->level += 1;
/* DB'PAGEs: 0------------------>MAX
*
* CURSORs: x < y
* STACK[i ]: |
* STACK[+1]: ...x--N|0--y...
*/
nkeys = NUMKEYS(x->mc_pg[r->level]);
r->diff = -(nkeys - x->mc_ki[r->level]) - y->mc_ki[r->level];
assert(r->diff < 0);
}
return MDBX_SUCCESS;
}
r->diff = mdbx_cmp2int(x->mc_flags & C_EOF, y->mc_flags & C_EOF);
return MDBX_SUCCESS;
}
__hot static ptrdiff_t estimate(const MDBX_db *db,
struct diff_result *const __restrict dr) {
/* root: branch-page => scale = leaf-factor * branch-factor^(N-1)
* level-1: branch-page(s) => scale = leaf-factor * branch-factor^2
* level-2: branch-page(s) => scale = leaf-factor * branch-factor
* level-N: branch-page(s) => scale = leaf-factor
* last-level: leaf-page(s) => scale = 1
*/
ptrdiff_t btree_power = db->md_depth - 2 - dr->level;
if (btree_power < 0)
return dr->diff;
ptrdiff_t estimated =
(ptrdiff_t)db->md_entries * dr->diff / (ptrdiff_t)db->md_leaf_pages;
if (btree_power == 0)
return estimated;
if (db->md_depth < 4) {
assert(dr->level == 0 && btree_power == 1);
return (ptrdiff_t)db->md_entries * dr->diff / (ptrdiff_t)dr->root_nkeys;
}
/* average_branchpage_fillfactor = total(branch_entries) / branch_pages
total(branch_entries) = leaf_pages + branch_pages - 1 (root page) */
const size_t log2_fixedpoint = sizeof(size_t) - 1;
const size_t half = UINT64_C(1) << (log2_fixedpoint - 1);
const size_t factor =
((db->md_leaf_pages + db->md_branch_pages - 1) << log2_fixedpoint) /
db->md_branch_pages;
while (1) {
switch ((size_t)btree_power) {
default: {
const size_t square = (factor * factor + half) >> log2_fixedpoint;
const size_t quad = (square * square + half) >> log2_fixedpoint;
do {
estimated = estimated * quad + half;
estimated >>= log2_fixedpoint;
btree_power -= 4;
} while (btree_power >= 4);
continue;
}
case 3:
estimated = estimated * factor + half;
estimated >>= log2_fixedpoint;
__fallthrough /* fall through */;
case 2:
estimated = estimated * factor + half;
estimated >>= log2_fixedpoint;
__fallthrough /* fall through */;
case 1:
estimated = estimated * factor + half;
estimated >>= log2_fixedpoint;
__fallthrough /* fall through */;
case 0:
if (unlikely(estimated > (ptrdiff_t)db->md_entries))
return (ptrdiff_t)db->md_entries;
if (unlikely(estimated < -(ptrdiff_t)db->md_entries))
return -(ptrdiff_t)db->md_entries;
return estimated;
}
}
}
__hot int mdbx_estimate_distance(const MDBX_cursor *first,
const MDBX_cursor *last,
ptrdiff_t *distance_items) {
if (unlikely(first == NULL || last == NULL || distance_items == NULL))
return MDBX_EINVAL;
*distance_items = 0;
struct diff_result dr;
int rc = cursor_diff(last, first, &dr);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
if (unlikely(dr.diff == 0) &&
F_ISSET(first->mc_db->md_flags & first->mc_db->md_flags,
MDBX_DUPSORT | C_INITIALIZED)) {
first = &first->mc_xcursor->mx_cursor;
last = &last->mc_xcursor->mx_cursor;
rc = cursor_diff(first, last, &dr);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
if (likely(dr.diff != 0))
*distance_items = estimate(first->mc_db, &dr);
return MDBX_SUCCESS;
}
int mdbx_estimate_move(const MDBX_cursor *cursor, MDBX_val *key, MDBX_val *data,
MDBX_cursor_op move_op, ptrdiff_t *distance_items) {
if (unlikely(cursor == NULL || distance_items == NULL ||
move_op == MDBX_GET_CURRENT || move_op == MDBX_GET_MULTIPLE))
return MDBX_EINVAL;
if (unlikely(cursor->mc_signature != MDBX_MC_SIGNATURE))
return MDBX_EBADSIGN;
if (!(cursor->mc_flags & C_INITIALIZED))
return MDBX_ENODATA;
MDBX_cursor_couple next;
mdbx_cursor_copy(cursor, &next.outer);
next.outer.mc_xcursor = NULL;
if (cursor->mc_db->md_flags & MDBX_DUPSORT) {
next.outer.mc_xcursor = &next.inner;
int rc = mdbx_xcursor_init0(&next.outer);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
MDBX_xcursor *mx = &container_of(cursor, MDBX_cursor_couple, outer)->inner;
mdbx_cursor_copy(&mx->mx_cursor, &next.inner.mx_cursor);
}
MDBX_val stub = {0, 0};
if (data == NULL) {
const unsigned mask =
1 << MDBX_GET_BOTH | 1 << MDBX_GET_BOTH_RANGE | 1 << MDBX_SET_KEY;
if (unlikely(mask & (1 << move_op)))
return MDBX_EINVAL;
data = &stub;
}
if (key == NULL) {
const unsigned mask = 1 << MDBX_GET_BOTH | 1 << MDBX_GET_BOTH_RANGE |
1 << MDBX_SET_KEY | 1 << MDBX_SET |
1 << MDBX_SET_RANGE;
if (unlikely(mask & (1 << move_op)))
return MDBX_EINVAL;
key = &stub;
}
int rc = mdbx_cursor_get(&next.outer, key, data, move_op);
if (unlikely(rc != MDBX_SUCCESS &&
(rc != MDBX_NOTFOUND || !(next.outer.mc_flags & C_INITIALIZED))))
return rc;
return mdbx_estimate_distance(cursor, &next.outer, distance_items);
}
static int mdbx_is_samedata(const MDBX_val *a, const MDBX_val *b) {
return a->iov_len == b->iov_len &&
memcmp(a->iov_base, b->iov_base, a->iov_len) == 0;
}
int mdbx_estimate_range(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *begin_key,
MDBX_val *begin_data, MDBX_val *end_key,
MDBX_val *end_data, ptrdiff_t *size_items) {
if (unlikely(!txn || !size_items))
return MDBX_EINVAL;
if (unlikely(!begin_key && begin_data))
return MDBX_EINVAL;
if (unlikely(!end_key && end_data))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
MDBX_cursor_couple begin;
/* LY: first, initialize cursor to refresh a DB in case it have DB_STALE */
int rc = mdbx_cursor_init(&begin.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
if (unlikely(begin.outer.mc_db->md_entries == 0)) {
*size_items = 0;
return MDBX_SUCCESS;
}
if (!begin_key) {
if (unlikely(!end_key)) {
/* LY: FIRST..LAST case */
*size_items = (ptrdiff_t)begin.outer.mc_db->md_entries;
return MDBX_SUCCESS;
}
MDBX_val stub = {0, 0};
rc = mdbx_cursor_first(&begin.outer, &stub, &stub);
} else if (end_key && !begin_data && !end_data &&
(begin_key == end_key || mdbx_is_samedata(begin_key, end_key))) {
/* LY: single key case */
int exact = 0;
rc = mdbx_cursor_set(&begin.outer, begin_key, NULL, MDBX_SET, &exact);
if (unlikely(rc != MDBX_SUCCESS)) {
*size_items = 0;
return (rc == MDBX_NOTFOUND) ? MDBX_SUCCESS : rc;
}
*size_items = 1;
if (begin.outer.mc_xcursor != NULL) {
MDBX_node *leaf = NODEPTR(begin.outer.mc_pg[begin.outer.mc_top],
begin.outer.mc_ki[begin.outer.mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
/* LY: return the number of duplicates for given key */
mdbx_tassert(txn, begin.outer.mc_xcursor == &begin.inner &&
(begin.inner.mx_cursor.mc_flags & C_INITIALIZED));
*size_items =
(sizeof(*size_items) >= sizeof(begin.inner.mx_db.md_entries) ||
begin.inner.mx_db.md_entries <= SIZE_MAX)
? (size_t)begin.inner.mx_db.md_entries
: SIZE_MAX;
}
}
return MDBX_SUCCESS;
} else {
rc = mdbx_cursor_set(&begin.outer, begin_key, begin_data,
begin_data ? MDBX_GET_BOTH_RANGE : MDBX_SET_RANGE,
NULL);
}
if (unlikely(rc != MDBX_SUCCESS)) {
if (rc != MDBX_NOTFOUND || !(begin.outer.mc_flags & C_INITIALIZED))
return rc;
}
MDBX_cursor_couple end;
rc = mdbx_cursor_init(&end.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
if (!end_key) {
MDBX_val stub = {0, 0};
rc = mdbx_cursor_last(&end.outer, &stub, &stub);
} else {
rc = mdbx_cursor_set(&end.outer, end_key, end_data,
end_data ? MDBX_GET_BOTH_RANGE : MDBX_SET_RANGE, NULL);
}
if (unlikely(rc != MDBX_SUCCESS)) {
if (rc != MDBX_NOTFOUND || !(end.outer.mc_flags & C_INITIALIZED))
return rc;
}
rc = mdbx_estimate_distance(&begin.outer, &end.outer, size_items);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
assert(*size_items >= -(ptrdiff_t)begin.outer.mc_db->md_entries &&
*size_items <= (ptrdiff_t)begin.outer.mc_db->md_entries);
#if 0 /* LY: Was decided to returns as-is (i.e. negative) the estimation \
* results for an inverted ranges. */
/* Commit 8ddfd1f34ad7cf7a3c4aa75d2e248ca7e639ed63
Change-Id: If59eccf7311123ab6384c4b93f9b1fed5a0a10d1 */
if (*size_items < 0) {
/* LY: inverted range case */
*size_items += (ptrdiff_t)begin.outer.mc_db->md_entries;
} else if (*size_items == 0 && begin_key && end_key) {
int cmp = begin.outer.mc_dbx->md_cmp(&origin_begin_key, &origin_end_key);
if (cmp == 0 && (begin.inner.mx_cursor.mc_flags & C_INITIALIZED) &&
begin_data && end_data)
cmp = begin.outer.mc_dbx->md_dcmp(&origin_begin_data, &origin_end_data);
if (cmp > 0) {
/* LY: inverted range case with empty scope */
*size_items = (ptrdiff_t)begin.outer.mc_db->md_entries;
}
}
assert(*size_items >= 0 &&
*size_items <= (ptrdiff_t)begin.outer.mc_db->md_entries);
#endif
return MDBX_SUCCESS;
}
//------------------------------------------------------------------------------
/* Позволяет обновить или удалить существующую запись с получением
* в old_data предыдущего значения данных. При этом если new_data равен
* нулю, то выполняется удаление, иначе обновление/вставка.
*
* Текущее значение может находиться в уже измененной (грязной) странице.
* В этом случае страница будет перезаписана при обновлении, а само старое
* значение утрачено. Поэтому исходно в old_data должен быть предан
* дополнительный буфер для копирования старого значения.
* Если переданный буфер слишком мал, то функция вернет -1, установив
* old_data->iov_len в соответствующее значение.
*
* Для не-уникальных ключей также возможен второй сценарий использования,
* когда посредством old_data из записей с одинаковым ключом для
* удаления/обновления выбирается конкретная. Для выбора этого сценария
* во flags следует одновременно указать MDBX_CURRENT и MDBX_NOOVERWRITE.
* Именно та комбинация выбрана, так как она лишена смысла, и этим позволяет
* идентифицировать запрос такого сценария.
*
* Функция может быть замещена соответствующими операциями с курсорами
* после двух доработок (TODO):
* - внешняя аллокация курсоров, в том числе на стеке (без malloc).
* - получения статуса страницы по адресу (знать о P_DIRTY).
*/
int mdbx_replace(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *new_data,
MDBX_val *old_data, unsigned flags) {
if (unlikely(!key || !old_data || !txn || old_data == new_data))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(old_data->iov_base == NULL && old_data->iov_len))
return MDBX_EINVAL;
if (unlikely(new_data == NULL && !(flags & MDBX_CURRENT)))
return MDBX_EINVAL;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
if (unlikely(flags & ~(MDBX_NOOVERWRITE | MDBX_NODUPDATA | MDBX_RESERVE |
MDBX_APPEND | MDBX_APPENDDUP | MDBX_CURRENT)))
return MDBX_EINVAL;
if (unlikely(txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_BLOCKED)))
return (txn->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EACCESS : MDBX_BAD_TXN;
MDBX_cursor_couple cx;
int rc = mdbx_cursor_init(&cx.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
cx.outer.mc_next = txn->mt_cursors[dbi];
txn->mt_cursors[dbi] = &cx.outer;
MDBX_val present_key = *key;
if (F_ISSET(flags, MDBX_CURRENT | MDBX_NOOVERWRITE)) {
/* в old_data значение для выбора конкретного дубликата */
if (unlikely(!(txn->mt_dbs[dbi].md_flags & MDBX_DUPSORT))) {
rc = MDBX_EINVAL;
goto bailout;
}
/* убираем лишний бит, он был признаком запрошенного режима */
flags -= MDBX_NOOVERWRITE;
rc = mdbx_cursor_get(&cx.outer, &present_key, old_data, MDBX_GET_BOTH);
if (rc != MDBX_SUCCESS)
goto bailout;
if (new_data) {
/* обновление конкретного дубликата */
if (mdbx_is_samedata(old_data, new_data))
/* если данные совпадают, то ничего делать не надо */
goto bailout;
}
} else {
/* в old_data буфер для сохранения предыдущего значения */
if (unlikely(new_data && old_data->iov_base == new_data->iov_base))
return MDBX_EINVAL;
MDBX_val present_data;
rc = mdbx_cursor_get(&cx.outer, &present_key, &present_data, MDBX_SET_KEY);
if (unlikely(rc != MDBX_SUCCESS)) {
old_data->iov_base = NULL;
old_data->iov_len = 0;
if (rc != MDBX_NOTFOUND || (flags & MDBX_CURRENT))
goto bailout;
} else if (flags & MDBX_NOOVERWRITE) {
rc = MDBX_KEYEXIST;
*old_data = present_data;
goto bailout;
} else {
MDBX_page *page = cx.outer.mc_pg[cx.outer.mc_top];
if (txn->mt_dbs[dbi].md_flags & MDBX_DUPSORT) {
if (flags & MDBX_CURRENT) {
/* для не-уникальных ключей позволяем update/delete только если ключ
* один */
MDBX_node *leaf = NODEPTR(page, cx.outer.mc_ki[cx.outer.mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
mdbx_tassert(txn, XCURSOR_INITED(&cx.outer) &&
cx.outer.mc_xcursor->mx_db.md_entries > 1);
if (cx.outer.mc_xcursor->mx_db.md_entries > 1) {
rc = MDBX_EMULTIVAL;
goto bailout;
}
}
/* если данные совпадают, то ничего делать не надо */
if (new_data && mdbx_is_samedata(&present_data, new_data)) {
*old_data = *new_data;
goto bailout;
}
/* В оригинальной LMDB фладок MDBX_CURRENT здесь приведет
* к замене данных без учета MDBX_DUPSORT сортировки,
* но здесь это в любом случае допустимо, так как мы
* проверили что для ключа есть только одно значение. */
} else if ((flags & MDBX_NODUPDATA) &&
mdbx_is_samedata(&present_data, new_data)) {
/* если данные совпадают и установлен MDBX_NODUPDATA */
rc = MDBX_KEYEXIST;
goto bailout;
}
} else {
/* если данные совпадают, то ничего делать не надо */
if (new_data && mdbx_is_samedata(&present_data, new_data)) {
*old_data = *new_data;
goto bailout;
}
flags |= MDBX_CURRENT;
}
if (IS_DIRTY(page)) {
if (unlikely(old_data->iov_len < present_data.iov_len)) {
old_data->iov_base = NULL;
old_data->iov_len = present_data.iov_len;
rc = MDBX_RESULT_TRUE;
goto bailout;
}
memcpy(old_data->iov_base, present_data.iov_base, present_data.iov_len);
old_data->iov_len = present_data.iov_len;
} else {
*old_data = present_data;
}
}
}
if (likely(new_data))
rc = mdbx_cursor_put(&cx.outer, key, new_data, flags);
else
rc = mdbx_cursor_del(&cx.outer, 0);
bailout:
txn->mt_cursors[dbi] = cx.outer.mc_next;
return rc;
}
int mdbx_get_ex(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
size_t *values_count) {
DKBUF;
mdbx_debug("===> get db %u key [%s]", dbi, DKEY(key));
if (unlikely(!key || !data || !txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
MDBX_cursor_couple cx;
int rc = mdbx_cursor_init(&cx.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
int exact = 0;
rc = mdbx_cursor_set(&cx.outer, key, data, MDBX_SET_KEY, &exact);
if (unlikely(rc != MDBX_SUCCESS)) {
if (rc == MDBX_NOTFOUND && values_count)
*values_count = 0;
return rc;
}
if (values_count) {
*values_count = 1;
if (cx.outer.mc_xcursor != NULL) {
MDBX_node *leaf = NODEPTR(cx.outer.mc_pg[cx.outer.mc_top],
cx.outer.mc_ki[cx.outer.mc_top]);
if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
mdbx_tassert(txn, cx.outer.mc_xcursor == &cx.inner &&
(cx.inner.mx_cursor.mc_flags & C_INITIALIZED));
*values_count =
(sizeof(*values_count) >= sizeof(cx.inner.mx_db.md_entries) ||
cx.inner.mx_db.md_entries <= SIZE_MAX)
? (size_t)cx.inner.mx_db.md_entries
: SIZE_MAX;
}
}
}
return MDBX_SUCCESS;
}
/* Функция сообщает находится ли указанны адрес в "грязной" странице у
* заданной пишущей транзакции. В конечном счете это позволяет избавиться от
* лишнего копирования данных из НЕ-грязных страниц.
*
* "Грязные" страницы - это те, которые уже были изменены в ходе пишущей
* транзакции. Соответственно, какие-либо дальнейшие изменения могут привести
* к перезаписи таких страниц. Поэтому все функции, выполняющие изменения, в
* качестве аргументов НЕ должны получать указатели на данные в таких
* страницах. В свою очередь "НЕ грязные" страницы перед модификацией будут
* скопированы.
*
* Другими словами, данные из "грязных" страниц должны быть либо скопированы
* перед передачей в качестве аргументов для дальнейших модификаций, либо
* отвергнуты на стадии проверки корректности аргументов.
*
* Таким образом, функция позволяет как избавится от лишнего копирования,
* так и выполнить более полную проверку аргументов.
*
* ВАЖНО: Передаваемый указатель должен указывать на начало данных. Только
* так гарантируется что актуальный заголовок страницы будет физически
* расположен в той-же странице памяти, в том числе для многостраничных
* P_OVERFLOW страниц с длинными данными. */
int mdbx_is_dirty(const MDBX_txn *txn, const void *ptr) {
if (unlikely(!txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(txn->mt_flags & MDBX_TXN_RDONLY))
return MDBX_RESULT_FALSE;
const MDBX_env *env = txn->mt_env;
const uintptr_t mask = ~(uintptr_t)(env->me_psize - 1);
const MDBX_page *page = (const MDBX_page *)((uintptr_t)ptr & mask);
/* LY: Тут не всё хорошо с абсолютной достоверностью результата,
* так как флажок P_DIRTY в LMDB может означать не совсем то,
* что было исходно задумано, детали см в логике кода mdbx_page_touch().
*
* Более того, в режиме БЕЗ WRITEMAP грязные страницы выделяются через
* malloc(), т.е. находятся вне mmap-диапазона и тогда чтобы отличить
* действительно грязную страницу от указателя на данные пользователя
* следует сканировать dirtylist, что накладно.
*
* Тем не менее, однозначно страница "не грязная" (не будет переписана
* во время транзакции) если адрес находится внутри mmap-диапазона
* и в заголовке страницы нет флажка P_DIRTY. */
if (env->me_map < (uint8_t *)page) {
const size_t usedbytes = pgno2bytes(env, txn->mt_next_pgno);
if ((uint8_t *)page < env->me_map + usedbytes) {
/* страница внутри диапазона, смотрим на флажки */
return (page->mp_flags & (P_DIRTY | P_LOOSE | P_KEEP))
? MDBX_RESULT_TRUE
: MDBX_RESULT_FALSE;
}
/* Гипотетически здесь возможна ситуация, когда указатель адресует что-то
* в пределах mmap, но за границей распределенных страниц. Это тяжелая
* ошибка, к которой не возможно прийти без каких-то больших нарушений.
* Поэтому не проверяем этот случай кроме как assert-ом, на то что
* страница вне mmap-диаппазона. */
mdbx_tassert(txn, (uint8_t *)page >= env->me_map + env->me_mapsize);
}
/* Страница вне используемого mmap-диапазона, т.е. либо в функцию был
* передан некорректный адрес, либо адрес в теневой странице, которая была
* выделена посредством malloc().
*
* Для WRITE_MAP режима такая страница однозначно "не грязная",
* а для режимов без WRITE_MAP следует просматривать списки dirty
* и spilled страниц у каких-либо транзакций (в том числе дочерних).
*
* Поэтому для WRITE_MAP возвращаем false, а для остальных режимов
* всегда true. Такая логика имеет ряд преимуществ:
* - не тратим время на просмотр списков;
* - результат всегда безопасен (может быть ложно-положительным,
* но не ложно-отрицательным);
* - результат не зависит от вложенности транзакций и от относительного
* положения переданной транзакции в этой рекурсии. */
return (env->me_flags & MDBX_WRITEMAP) ? MDBX_RESULT_FALSE : MDBX_RESULT_TRUE;
}
int mdbx_dbi_sequence(MDBX_txn *txn, MDBX_dbi dbi, uint64_t *result,
uint64_t increment) {
if (unlikely(!txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_EBADSIGN;
if (unlikely(txn->mt_owner != mdbx_thread_self()))
return MDBX_THREAD_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
if (unlikely(TXN_DBI_CHANGED(txn, dbi)))
return MDBX_BAD_DBI;
if (unlikely(txn->mt_dbflags[dbi] & DB_STALE)) {
MDBX_cursor_couple cx;
/* Stale, must read the DB's root. cursor_init does it for us. */
int rc = mdbx_cursor_init(&cx.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
}
MDBX_db *dbs = &txn->mt_dbs[dbi];
if (likely(result))
*result = dbs->md_seq;
if (likely(increment > 0)) {
if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
return MDBX_BAD_TXN;
if (unlikely(F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY)))
return MDBX_EACCESS;
uint64_t new = dbs->md_seq + increment;
if (unlikely(new < increment))
return MDBX_RESULT_TRUE;
mdbx_tassert(txn, new > dbs->md_seq);
dbs->md_seq = new;
txn->mt_flags |= MDBX_TXN_DIRTY;
txn->mt_dbflags[dbi] |= DB_DIRTY;
}
return MDBX_SUCCESS;
}
/*----------------------------------------------------------------------------*/
__cold intptr_t mdbx_limits_keysize_max(intptr_t pagesize) {
if (pagesize < 1)
pagesize = (intptr_t)mdbx_syspagesize();
else if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
pagesize > (intptr_t)MAX_PAGESIZE ||
!mdbx_is_power2((size_t)pagesize)))
return (MDBX_EINVAL > 0) ? -MDBX_EINVAL : MDBX_EINVAL;
return mdbx_maxkey(mdbx_nodemax(pagesize));
}
__cold int mdbx_limits_pgsize_min(void) { return MIN_PAGESIZE; }
__cold int mdbx_limits_pgsize_max(void) { return MAX_PAGESIZE; }
__cold intptr_t mdbx_limits_dbsize_min(intptr_t pagesize) {
if (pagesize < 1)
pagesize = (intptr_t)mdbx_syspagesize();
else if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
pagesize > (intptr_t)MAX_PAGESIZE ||
!mdbx_is_power2((size_t)pagesize)))
return (MDBX_EINVAL > 0) ? -MDBX_EINVAL : MDBX_EINVAL;
return MIN_PAGENO * pagesize;
}
__cold intptr_t mdbx_limits_dbsize_max(intptr_t pagesize) {
if (pagesize < 1)
pagesize = (intptr_t)mdbx_syspagesize();
else if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
pagesize > (intptr_t)MAX_PAGESIZE ||
!mdbx_is_power2((size_t)pagesize)))
return (MDBX_EINVAL > 0) ? -MDBX_EINVAL : MDBX_EINVAL;
const uint64_t limit = MAX_PAGENO * (uint64_t)pagesize;
return (limit < (intptr_t)MAX_MAPSIZE) ? (intptr_t)limit
: (intptr_t)MAX_MAPSIZE;
}
__cold intptr_t mdbx_limits_txnsize_max(intptr_t pagesize) {
if (pagesize < 1)
pagesize = (intptr_t)mdbx_syspagesize();
else if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
pagesize > (intptr_t)MAX_PAGESIZE ||
!mdbx_is_power2((size_t)pagesize)))
return (MDBX_EINVAL > 0) ? -MDBX_EINVAL : MDBX_EINVAL;
return pagesize * (MDBX_DPL_TXNFULL - 1);
}
/*----------------------------------------------------------------------------*/
/* attribute support functions for Nexenta */
static __inline int mdbx_attr_peek(MDBX_val *data, mdbx_attr_t *attrptr) {
if (unlikely(data->iov_len < sizeof(mdbx_attr_t)))
return MDBX_INCOMPATIBLE;
if (likely(attrptr != NULL))
*attrptr = *(mdbx_attr_t *)data->iov_base;
data->iov_len -= sizeof(mdbx_attr_t);
data->iov_base =
likely(data->iov_len > 0) ? ((mdbx_attr_t *)data->iov_base) + 1 : NULL;
return MDBX_SUCCESS;
}
static __inline int mdbx_attr_poke(MDBX_val *reserved, MDBX_val *data,
mdbx_attr_t attr, unsigned flags) {
mdbx_attr_t *space = reserved->iov_base;
if (flags & MDBX_RESERVE) {
if (likely(data != NULL)) {
data->iov_base = data->iov_len ? space + 1 : NULL;
}
} else {
*space = attr;
if (likely(data != NULL)) {
memcpy(space + 1, data->iov_base, data->iov_len);
}
}
return MDBX_SUCCESS;
}
int mdbx_cursor_get_attr(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
mdbx_attr_t *attrptr, MDBX_cursor_op op) {
int rc = mdbx_cursor_get(mc, key, data, op);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
return mdbx_attr_peek(data, attrptr);
}
int mdbx_get_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
uint64_t *attrptr) {
int rc = mdbx_get(txn, dbi, key, data);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
return mdbx_attr_peek(data, attrptr);
}
int mdbx_put_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
mdbx_attr_t attr, unsigned flags) {
MDBX_val reserve;
reserve.iov_base = NULL;
reserve.iov_len = (data ? data->iov_len : 0) + sizeof(mdbx_attr_t);
int rc = mdbx_put(txn, dbi, key, &reserve, flags | MDBX_RESERVE);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
return mdbx_attr_poke(&reserve, data, attr, flags);
}
int mdbx_cursor_put_attr(MDBX_cursor *cursor, MDBX_val *key, MDBX_val *data,
mdbx_attr_t attr, unsigned flags) {
MDBX_val reserve;
reserve.iov_base = NULL;
reserve.iov_len = (data ? data->iov_len : 0) + sizeof(mdbx_attr_t);
int rc = mdbx_cursor_put(cursor, key, &reserve, flags | MDBX_RESERVE);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
return mdbx_attr_poke(&reserve, data, attr, flags);
}
int mdbx_set_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
mdbx_attr_t attr) {
if (unlikely(!key || !txn))
return MDBX_EINVAL;
if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
return MDBX_VERSION_MISMATCH;
if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
return MDBX_EINVAL;
if (unlikely(txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_BLOCKED)))
return (txn->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EACCESS : MDBX_BAD_TXN;
MDBX_cursor_couple cx;
MDBX_val old_data;
int rc = mdbx_cursor_init(&cx.outer, txn, dbi);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
rc = mdbx_cursor_set(&cx.outer, key, &old_data, MDBX_SET, NULL);
if (unlikely(rc != MDBX_SUCCESS)) {
if (rc == MDBX_NOTFOUND && data) {
cx.outer.mc_next = txn->mt_cursors[dbi];
txn->mt_cursors[dbi] = &cx.outer;
rc = mdbx_cursor_put_attr(&cx.outer, key, data, attr, 0);
txn->mt_cursors[dbi] = cx.outer.mc_next;
}
return rc;
}
mdbx_attr_t old_attr = 0;
rc = mdbx_attr_peek(&old_data, &old_attr);
if (unlikely(rc != MDBX_SUCCESS))
return rc;
if (old_attr == attr && (!data || (data->iov_len == old_data.iov_len &&
memcmp(data->iov_base, old_data.iov_base,
old_data.iov_len) == 0)))
return MDBX_SUCCESS;
cx.outer.mc_next = txn->mt_cursors[dbi];
txn->mt_cursors[dbi] = &cx.outer;
rc = mdbx_cursor_put_attr(&cx.outer, key, data ? data : &old_data, attr,
MDBX_CURRENT);
txn->mt_cursors[dbi] = cx.outer.mc_next;
return rc;
}
//----------------------------------------------------------------------------
#ifdef __SANITIZE_ADDRESS__
LIBMDBX_API __attribute__((weak)) const char *__asan_default_options() {
return "symbolize=1:allow_addr2line=1:"
#ifdef _DEBUG
"debug=1:"
#endif /* _DEBUG */
"report_globals=1:"
"replace_str=1:replace_intrin=1:"
"malloc_context_size=9:"
"detect_leaks=1:"
"check_printf=1:"
"detect_deadlocks=1:"
#ifndef LTO_ENABLED
"check_initialization_order=1:"
#endif
"detect_stack_use_after_return=1:"
"intercept_tls_get_addr=1:"
"decorate_proc_maps=1:"
"abort_on_error=1";
}
#endif /* __SANITIZE_ADDRESS__ */
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V114 Dangerous explicit type pointer conversion.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V220 Suspicious sequence of types castings: memsize -> 32-bit integer -> memsize.
↑ V105 Third operand of '?:' operation: implicit type conversion to memsize type.
↑ V119 More than one sizeof() operator is used in one expression.
↑ V119 More than one sizeof() operator is used in one expression.
↑ V119 More than one sizeof() operator is used in one expression.
↑ V119 More than one sizeof() operator is used in one expression.
↑ V119 More than one sizeof() operator is used in one expression.
↑ V105 Third operand of '?:' operation: implicit type conversion to memsize type.
↑ V119 More than one sizeof() operator is used in one expression.
↑ V562 It's odd to compare 0 or 1 with a value of 0: (sizeof (pgno_t) % 2 == 0) != 0.
↑ V562 It's odd to compare 0 or 1 with a value of 0.
↑ V562 It's odd to compare 0 or 1 with a value of 0.
↑ V547 Expression 'sign > 1u' is always false.
↑ V501 There are identical sub-expressions 'first->mc_db->md_flags' to the left and to the right of the '&' operator.
↑ V560 A part of conditional expression is always true: 1.
↑ V1032 The pointer 'mp' is cast to a more strictly aligned pointer type.
↑ V547 Expression is always false.
↑ V560 A part of conditional expression is always true.
↑ V560 A part of conditional expression is always true: 1.
↑ V650 Type casting operation is utilized 2 times in succession. Next, the '-' operation is executed. Probably meant: (T1)((T2)a - b).
↑ V560 A part of conditional expression is always true.
↑ V650 Type casting operation is utilized 2 times in succession. Next, the '-' operation is executed. Probably meant: (T1)((T2)a - b).
↑ V1032 The pointer 'mp' is cast to a more strictly aligned pointer type.
↑ V1032 The pointer 'np' is cast to a more strictly aligned pointer type.
↑ V1032 The pointer 'mp' is cast to a more strictly aligned pointer type.
↑ V1032 The pointer 'mp' is cast to a more strictly aligned pointer type.
↑ V1032 The pointer 'mp' is cast to a more strictly aligned pointer type.
↑ V547 Expression 'shrink_threshold < 0' is always false.
↑ V560 A part of conditional expression is always true.
↑ V547 Expression 'growth_step < 0' is always false.
↑ V1032 The pointer '* lp' is cast to a more strictly aligned pointer type.
↑ V547 Expression 'growth_step < 0' is always false.
↑ V547 Expression 'shrink_threshold < 0' is always false.
↑ V1019 Compound assignment expression 'unused &= - Align' is used inside condition.
↑ V576 Incorrect format. Consider checking the sixth actual argument of the '_snprintf' function. The SIGNED integer type argument is expected.
↑ V506 Pointer to local variable 'fill_gc_id' is stored outside the scope of this variable. Such a pointer will become invalid.
↑ V506 Pointer to local variable 'fill_gc_id' is stored outside the scope of this variable. Such a pointer will become invalid.
↑ V641 The size of the '& (mc)' buffer is not a multiple of the element size of the type 'MDBX_xcursor'.
↑ V641 The size of the '& (mn)' buffer is not a multiple of the element size of the type 'MDBX_xcursor'.
↑ V641 The size of the '& (mn)' buffer is not a multiple of the element size of the type 'MDBX_xcursor'.
↑ V641 The size of the '& (mn)' buffer is not a multiple of the element size of the type 'MDBX_xcursor'.
↑ V641 The size of the '& (mn)' buffer is not a multiple of the element size of the type 'MDBX_xcursor'.
↑ V641 The size of the '& (mc)' buffer is not a multiple of the element size of the type 'MDBX_xcursor'.
↑ V522 There might be dereferencing of a potential null pointer 'copy'.
↑ V522 Dereferencing of the null pointer 'b' might take place. The potential null pointer is passed into 'mdbx_is_samedata' function. Inspect the second argument. Check lines: 13397, 13649.
↑ V522 There might be dereferencing of a potential null pointer 'sl'.
↑ V658 A value is being subtracted from the unsigned variable. This can result in an overflow. In such a case, the '>' comparison operation can potentially behave unexpectedly.
↑ V522 There might be dereferencing of a potential null pointer 'leaf'.
↑ V658 A value is being subtracted from the unsigned variable. This can result in an overflow. In such a case, the '>=' comparison operation can potentially behave unexpectedly.
↑ V658 A value is being subtracted from the unsigned variable. This can result in an overflow. In such a case, the '>=' comparison operation can potentially behave unexpectedly. Consider inspecting the '(size_t) 0xffffui16 - mp->mp_upper >= sz' expression.
↑ V658 A value is being subtracted from the unsigned variable. This can result in an overflow. In such a case, the '>=' comparison operation can potentially behave unexpectedly.
↑ V658 A value is being subtracted from the unsigned variable. This can result in an overflow. In such a case, the '>=' comparison operation can potentially behave unexpectedly.
↑ V522 There might be dereferencing of a potential null pointer 'leaf'.
↑ V769 The '(char *) data[0].iov_base' pointer in the expression could be nullptr. In such case, resulting value of arithmetic operations on this pointer will be senseless and it should not be used.
↑ V522 There might be dereferencing of a potential null pointer '(txnid_t *) key.iov_base'.
↑ V658 A value is being subtracted from the unsigned variable. This can result in an overflow. In such a case, the '>=' comparison operation can potentially behave unexpectedly.
↑ V547 Expression 'subtype == MDBX_subpage_leaf' is always true.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 7325, 7334.
↑ V547 Expression 'r->mr_txnid == snap' is always true.
↑ V547 Expression 'rc != 0' is always true.
↑ V575 The potential null pointer is passed into 'memcpy' function. Inspect the first argument.
↑ V547 Expression 'rc == (- 30798)' is always true.
↑ V547 Expression 'm3->mc_ki[mc->mc_top] >= nkeys' is always true.
↑ V547 Expression is always true.
↑ V547 Expression 'rc == 0' is always true.
↑ V547 Expression 'mx != NULL' is always true.
↑ V547 Expression is always false.
↑ V547 Expression 'nsize % 1 == 0' is always true.
↑ V547 Expression 'nkeys > 0' is always true.
↑ V547 Expression 'nkeys <= 0xffffui16' is always true.
↑ V547 Expression 'nkeys <= 0xffffui16' is always true.
↑ V547 Expression 'x > 1' is always false.
↑ V547 Expression 'mc->mc_snum < 0xffffui16' is always true.
↑ V526 The 'memcmp' function returns 0 if corresponding buffers are equal. Consider examining the condition for mistakes.
↑ V526 The 'memcmp' function returns 0 if corresponding buffers are equal. Consider examining the condition for mistakes.
↑ V547 Expression 'type == MDBX_page_leaf' is always true.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 7324, 7325.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 2902, 2916.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 1936, 1937.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 7031, 7033.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 1740, 1742.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 1649, 1653.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 2900, 2902.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 1105, 1108.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 1085, 1088.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 1041, 1053.
↑ V574 The 'dl' pointer is used simultaneously as an array and as a pointer to single object. Check lines: 1646, 1649.