/*
Unix SMB/CIFS implementation.
trivial database library
Copyright (C) Andrew Tridgell 1999-2005
Copyright (C) Paul `Rusty' Russell 2000
Copyright (C) Jeremy Allison 2000-2003
** NOTE! The following LGPL license applies to the tdb
** library. This does NOT imply that all of Samba is released
** under the LGPL
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 3 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "tdb_private.h"
/* all contexts, to ensure no double-opens (fcntl locks don't nest!) */
static struct tdb_context *tdbs = NULL;
/* We use two hashes to double-check they're using the right hash function. */
void tdb_header_hash(struct tdb_context *tdb,
uint32_t *magic1_hash, uint32_t *magic2_hash)
{
TDB_DATA hash_key;
uint32_t tdb_magic = TDB_MAGIC;
hash_key.dptr = discard_const_p(unsigned char, TDB_MAGIC_FOOD);
hash_key.dsize = sizeof(TDB_MAGIC_FOOD);
*magic1_hash = tdb->hash_fn(&hash_key);
hash_key.dptr = (unsigned char *)CONVERT(tdb_magic);
hash_key.dsize = sizeof(tdb_magic);
*magic2_hash = tdb->hash_fn(&hash_key);
/* Make sure at least one hash is non-zero! */
if (*magic1_hash == 0 && *magic2_hash == 0)
*magic1_hash = 1;
}
/* initialise a new database with a specified hash size */
static int tdb_new_database(struct tdb_context *tdb, struct tdb_header *header,
int hash_size)
{
struct tdb_header *newdb;
size_t size;
int ret = -1;
/* We make it up in memory, then write it out if not internal */
size = sizeof(struct tdb_header) + (hash_size+1)*sizeof(tdb_off_t);
if (!(newdb = (struct tdb_header *)calloc(size, 1))) {
tdb->ecode = TDB_ERR_OOM;
return -1;
}
/* Fill in the header */
newdb->version = TDB_VERSION;
newdb->hash_size = hash_size;
tdb_header_hash(tdb, &newdb->magic1_hash, &newdb->magic2_hash);
/* Make sure older tdbs (which don't check the magic hash fields)
* will refuse to open this TDB. */
if (tdb->flags & TDB_INCOMPATIBLE_HASH)
newdb->rwlocks = TDB_HASH_RWLOCK_MAGIC;
/*
* We create a tdb with TDB_FEATURE_FLAG_MUTEX support,
* the flag combination and runtime feature checks
* are done by the caller already.
*/
if (tdb->flags & TDB_MUTEX_LOCKING) {
newdb->feature_flags |= TDB_FEATURE_FLAG_MUTEX;
}
/*
* If we have any features we add the FEATURE_FLAG_MAGIC, overwriting the
* TDB_HASH_RWLOCK_MAGIC above.
*/
if (newdb->feature_flags != 0) {
newdb->rwlocks = TDB_FEATURE_FLAG_MAGIC;
}
/*
* It's required for some following code pathes
* to have the fields on 'tdb' up-to-date.
*
* E.g. tdb_mutex_size() requires it
*/
tdb->feature_flags = newdb->feature_flags;
tdb->hash_size = newdb->hash_size;
if (tdb->flags & TDB_INTERNAL) {
tdb->map_size = size;
tdb->map_ptr = (char *)newdb;
memcpy(header, newdb, sizeof(*header));
/* Convert the `ondisk' version if asked. */
CONVERT(*newdb);
return 0;
}
if (lseek(tdb->fd, 0, SEEK_SET) == -1)
goto fail;
if (ftruncate(tdb->fd, 0) == -1)
goto fail;
if (newdb->feature_flags & TDB_FEATURE_FLAG_MUTEX) {
newdb->mutex_size = tdb_mutex_size(tdb);
tdb->hdr_ofs = newdb->mutex_size;
}
/* This creates an endian-converted header, as if read from disk */
CONVERT(*newdb);
memcpy(header, newdb, sizeof(*header));
/* Don't endian-convert the magic food! */
memcpy(newdb->magic_food, TDB_MAGIC_FOOD, strlen(TDB_MAGIC_FOOD)+1);
if (!tdb_write_all(tdb->fd, newdb, size))
goto fail;
if (newdb->feature_flags & TDB_FEATURE_FLAG_MUTEX) {
/*
* Now we init the mutex area
* followed by a second header.
*/
ret = ftruncate(
tdb->fd,
newdb->mutex_size + sizeof(struct tdb_header));
if (ret == -1) {
goto fail;
}
ret = tdb_mutex_init(tdb);
if (ret == -1) {
goto fail;
}
/*
* Write a second header behind the mutexes. That's the area
* that will be mmapp'ed.
*/
ret = lseek(tdb->fd, newdb->mutex_size, SEEK_SET);
if (ret == -1) {
goto fail;
}
if (!tdb_write_all(tdb->fd, newdb, size)) {
goto fail;
}
}
ret = 0;
fail:
SAFE_FREE(newdb);
return ret;
}
static int tdb_already_open(dev_t device,
ino_t ino)
{
struct tdb_context *i;
for (i = tdbs; i; i = i->next) {
if (i->device == device && i->inode == ino) {
return 1;
}
}
return 0;
}
/* open the database, creating it if necessary
The open_flags and mode are passed straight to the open call on the
database file. A flags value of O_WRONLY is invalid. The hash size
is advisory, use zero for a default value.
Return is NULL on error, in which case errno is also set. Don't
try to call tdb_error or tdb_errname, just do strerror(errno).
@param name may be NULL for internal databases. */
_PUBLIC_ struct tdb_context *tdb_open(const char *name, int hash_size, int tdb_flags,
int open_flags, mode_t mode)
{
return tdb_open_ex(name, hash_size, tdb_flags, open_flags, mode, NULL, NULL);
}
/* a default logging function */
static void null_log_fn(struct tdb_context *tdb, enum tdb_debug_level level, const char *fmt, ...) PRINTF_ATTRIBUTE(3, 4);
static void null_log_fn(struct tdb_context *tdb, enum tdb_debug_level level, const char *fmt, ...)
{
}
static bool check_header_hash(struct tdb_context *tdb,
struct tdb_header *header,
bool default_hash, uint32_t *m1, uint32_t *m2)
{
tdb_header_hash(tdb, m1, m2);
if (header->magic1_hash == *m1 &&
header->magic2_hash == *m2) {
return true;
}
/* If they explicitly set a hash, always respect it. */
if (!default_hash)
return false;
/* Otherwise, try the other inbuilt hash. */
if (tdb->hash_fn == tdb_old_hash)
tdb->hash_fn = tdb_jenkins_hash;
else
tdb->hash_fn = tdb_old_hash;
return check_header_hash(tdb, header, false, m1, m2);
}
static bool tdb_mutex_open_ok(struct tdb_context *tdb,
const struct tdb_header *header)
{
if (tdb->flags & TDB_NOLOCK) {
/*
* We don't look at locks, so it does not matter to have a
* compatible mutex implementation. Allow the open.
*/
return true;
}
if (!(tdb->flags & TDB_MUTEX_LOCKING)) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_mutex_open_ok[%s]: "
"Can use mutexes only with "
"MUTEX_LOCKING or NOLOCK\n",
tdb->name));
return false;
}
if (tdb_mutex_size(tdb) != header->mutex_size) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_mutex_open_ok[%s]: "
"Mutex size changed from %"PRIu32" to %zu\n.",
tdb->name,
header->mutex_size,
tdb_mutex_size(tdb)));
return false;
}
return true;
}
_PUBLIC_ struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
int open_flags, mode_t mode,
const struct tdb_logging_context *log_ctx,
tdb_hash_func hash_fn)
{
int orig_errno = errno;
struct tdb_header header = {
.version = 0,
};
struct tdb_context *tdb;
struct stat st;
int rev = 0;
bool locked = false;
unsigned char *vp;
uint32_t vertest;
unsigned v;
const char *hash_alg;
uint32_t magic1, magic2;
int ret;
if (!(tdb = (struct tdb_context *)calloc(1, sizeof *tdb))) {
/* Can't log this */
errno = ENOMEM;
goto fail;
}
tdb_io_init(tdb);
if (tdb_flags & TDB_INTERNAL) {
tdb_flags |= TDB_INCOMPATIBLE_HASH;
}
if (tdb_flags & TDB_MUTEX_LOCKING) {
tdb_flags |= TDB_INCOMPATIBLE_HASH;
}
tdb->fd = -1;
#ifdef TDB_TRACE
tdb->tracefd = -1;
#endif
tdb->name = NULL;
tdb->map_ptr = NULL;
tdb->flags = tdb_flags;
tdb->open_flags = open_flags;
if (log_ctx) {
tdb->log = *log_ctx;
} else {
tdb->log.log_fn = null_log_fn;
tdb->log.log_private = NULL;
}
if (name == NULL && (tdb_flags & TDB_INTERNAL)) {
name = "__TDB_INTERNAL__";
}
if (name == NULL) {
tdb->name = discard_const_p(char, "__NULL__");
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: called with name == NULL\n"));
tdb->name = NULL;
errno = EINVAL;
goto fail;
}
/* now make a copy of the name, as the caller memory might go away */
if (!(tdb->name = (char *)strdup(name))) {
/*
* set the name as the given string, so that tdb_name() will
* work in case of an error.
*/
tdb->name = discard_const_p(char, name);
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: can't strdup(%s)\n",
name));
tdb->name = NULL;
errno = ENOMEM;
goto fail;
}
if (hash_fn) {
tdb->hash_fn = hash_fn;
hash_alg = "the user defined";
} else {
/* This controls what we use when creating a tdb. */
if (tdb->flags & TDB_INCOMPATIBLE_HASH) {
tdb->hash_fn = tdb_jenkins_hash;
} else {
tdb->hash_fn = tdb_old_hash;
}
hash_alg = "either default";
}
/* cache the page size */
tdb->page_size = getpagesize();
if (tdb->page_size <= 0) {
tdb->page_size = 0x2000;
}
tdb->max_dead_records = (tdb_flags & TDB_VOLATILE) ? 5 : 0;
if ((open_flags & O_ACCMODE) == O_WRONLY) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: can't open tdb %s write-only\n",
name));
errno = EINVAL;
goto fail;
}
if (hash_size == 0)
hash_size = DEFAULT_HASH_SIZE;
if ((open_flags & O_ACCMODE) == O_RDONLY) {
tdb->read_only = 1;
/* read only databases don't do locking or clear if first */
tdb->flags |= TDB_NOLOCK;
tdb->flags &= ~(TDB_CLEAR_IF_FIRST|TDB_MUTEX_LOCKING);
}
if ((tdb->flags & TDB_ALLOW_NESTING) &&
(tdb->flags & TDB_DISALLOW_NESTING)) {
tdb->ecode = TDB_ERR_NESTING;
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
"allow_nesting and disallow_nesting are not allowed together!"));
errno = EINVAL;
goto fail;
}
if (tdb->flags & TDB_MUTEX_LOCKING) {
/*
* Here we catch bugs in the callers,
* the runtime check for existing tdb's comes later.
*/
if (tdb->flags & TDB_INTERNAL) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: "
"invalid flags for %s - TDB_MUTEX_LOCKING and "
"TDB_INTERNAL are not allowed together\n", name));
errno = EINVAL;
goto fail;
}
if (tdb->flags & TDB_NOMMAP) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: "
"invalid flags for %s - TDB_MUTEX_LOCKING and "
"TDB_NOMMAP are not allowed together\n", name));
errno = EINVAL;
goto fail;
}
if (tdb->read_only) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: "
"invalid flags for %s - TDB_MUTEX_LOCKING "
"not allowed read only\n", name));
errno = EINVAL;
goto fail;
}
/*
* The callers should have called
* tdb_runtime_check_for_robust_mutexes()
* before using TDB_MUTEX_LOCKING!
*
* This makes sure the caller understands
* that the locking may behave a bit differently
* than with pure fcntl locking. E.g. multiple
* read locks are not supported.
*/
if (!tdb_runtime_check_for_robust_mutexes()) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: "
"invalid flags for %s - TDB_MUTEX_LOCKING "
"requires support for robust_mutexes\n",
name));
errno = ENOSYS;
goto fail;
}
}
if (getenv("TDB_NO_FSYNC")) {
tdb->flags |= TDB_NOSYNC;
}
/*
* TDB_ALLOW_NESTING is the default behavior.
* Note: this may change in future versions!
*/
if (!(tdb->flags & TDB_DISALLOW_NESTING)) {
tdb->flags |= TDB_ALLOW_NESTING;
}
/* internal databases don't mmap or lock, and start off cleared */
if (tdb->flags & TDB_INTERNAL) {
tdb->flags |= (TDB_NOLOCK | TDB_NOMMAP);
tdb->flags &= ~TDB_CLEAR_IF_FIRST;
if (tdb_new_database(tdb, &header, hash_size) != 0) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: tdb_new_database failed!"));
goto fail;
}
tdb->hash_size = hash_size;
goto internal;
}
if ((tdb->fd = open(name, open_flags, mode)) == -1) {
TDB_LOG((tdb, TDB_DEBUG_WARNING, "tdb_open_ex: could not open file %s: %s\n",
name, strerror(errno)));
goto fail; /* errno set by open(2) */
}
/* on exec, don't inherit the fd */
v = fcntl(tdb->fd, F_GETFD, 0);
fcntl(tdb->fd, F_SETFD, v | FD_CLOEXEC);
/* ensure there is only one process initialising at once */
if (tdb_nest_lock(tdb, OPEN_LOCK, F_WRLCK, TDB_LOCK_WAIT) == -1) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: failed to get open lock on %s: %s\n",
name, strerror(errno)));
goto fail; /* errno set by tdb_brlock */
}
/* we need to zero database if we are the only one with it open */
if ((tdb_flags & TDB_CLEAR_IF_FIRST) &&
(!tdb->read_only)) {
ret = tdb_nest_lock(tdb, ACTIVE_LOCK, F_WRLCK,
TDB_LOCK_NOWAIT|TDB_LOCK_PROBE);
locked = (ret == 0);
if (locked) {
ret = tdb_brlock(tdb, F_WRLCK, FREELIST_TOP, 0,
TDB_LOCK_WAIT);
if (ret == -1) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
"tdb_brlock failed for %s: %s\n",
name, strerror(errno)));
goto fail;
}
ret = tdb_new_database(tdb, &header, hash_size);
if (ret == -1) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
"tdb_new_database failed for "
"%s: %s\n", name, strerror(errno)));
tdb_unlockall(tdb);
goto fail;
}
ret = tdb_brunlock(tdb, F_WRLCK, FREELIST_TOP, 0);
if (ret == -1) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
"tdb_unlockall failed for %s: %s\n",
name, strerror(errno)));
goto fail;
}
ret = lseek(tdb->fd, 0, SEEK_SET);
if (ret == -1) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
"lseek failed for %s: %s\n",
name, strerror(errno)));
goto fail;
}
}
}
errno = 0;
if (read(tdb->fd, &header, sizeof(header)) != sizeof(header)
|| strcmp(header.magic_food, TDB_MAGIC_FOOD) != 0) {
if (!(open_flags & O_CREAT) ||
tdb_new_database(tdb, &header, hash_size) == -1) {
if (errno == 0) {
errno = EIO; /* ie bad format or something */
}
goto fail;
}
rev = (tdb->flags & TDB_CONVERT);
} else if (header.version != TDB_VERSION
&& !(rev = (header.version==TDB_BYTEREV(TDB_VERSION)))) {
/* wrong version */
errno = EIO;
goto fail;
}
vp = (unsigned char *)&header.version;
vertest = (((uint32_t)vp[0]) << 24) | (((uint32_t)vp[1]) << 16) |
(((uint32_t)vp[2]) << 8) | (uint32_t)vp[3];
tdb->flags |= (vertest==TDB_VERSION) ? TDB_BIGENDIAN : 0;
if (!rev)
tdb->flags &= ~TDB_CONVERT;
else {
tdb->flags |= TDB_CONVERT;
tdb_convert(&header, sizeof(header));
}
/*
* We only use st.st_dev and st.st_ino from the raw fstat()
* call, everything else needs to use tdb_fstat() in order
* to skip tdb->hdr_ofs!
*/
if (fstat(tdb->fd, &st) == -1) {
goto fail;
}
tdb->device = st.st_dev;
tdb->inode = st.st_ino;
ZERO_STRUCT(st);
if (header.rwlocks != 0 &&
header.rwlocks != TDB_FEATURE_FLAG_MAGIC &&
header.rwlocks != TDB_HASH_RWLOCK_MAGIC) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: spinlocks no longer supported\n"));
errno = ENOSYS;
goto fail;
}
if (header.hash_size == 0) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: invalid database: 0 hash_size\n"));
errno = ENOSYS;
goto fail;
}
tdb->hash_size = header.hash_size;
if (header.rwlocks == TDB_FEATURE_FLAG_MAGIC) {
tdb->feature_flags = header.feature_flags;
}
if (tdb->feature_flags & ~TDB_SUPPORTED_FEATURE_FLAGS) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: unsupported "
"features in tdb %s: 0x%08x (supported: 0x%08x)\n",
name, (unsigned)tdb->feature_flags,
(unsigned)TDB_SUPPORTED_FEATURE_FLAGS));
errno = ENOSYS;
goto fail;
}
if (tdb->feature_flags & TDB_FEATURE_FLAG_MUTEX) {
if (!tdb_mutex_open_ok(tdb, &header)) {
errno = EINVAL;
goto fail;
}
/*
* We need to remember the hdr_ofs
* also for the TDB_NOLOCK case
* if the current library doesn't support
* mutex locking.
*/
tdb->hdr_ofs = header.mutex_size;
if ((!(tdb_flags & TDB_CLEAR_IF_FIRST)) && (!tdb->read_only)) {
/*
* Open an existing mutexed tdb, but without
* CLEAR_IF_FIRST. We need to initialize the
* mutex array and keep the CLEAR_IF_FIRST
* lock locked.
*/
ret = tdb_nest_lock(tdb, ACTIVE_LOCK, F_WRLCK,
TDB_LOCK_NOWAIT|TDB_LOCK_PROBE);
locked = (ret == 0);
if (locked) {
ret = tdb_mutex_init(tdb);
if (ret == -1) {
TDB_LOG((tdb,
TDB_DEBUG_FATAL,
"tdb_open_ex: tdb_mutex_init "
"failed for ""%s: %s\n",
name, strerror(errno)));
goto fail;
}
}
}
}
if ((header.magic1_hash == 0) && (header.magic2_hash == 0)) {
/* older TDB without magic hash references */
tdb->hash_fn = tdb_old_hash;
} else if (!check_header_hash(tdb, &header, !hash_fn,
&magic1, &magic2)) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
"%s was not created with %s hash function we are using\n"
"magic1_hash[0x%08X %s 0x%08X] "
"magic2_hash[0x%08X %s 0x%08X]\n",
name, hash_alg,
header.magic1_hash,
(header.magic1_hash == magic1) ? "==" : "!=",
magic1,
header.magic2_hash,
(header.magic2_hash == magic2) ? "==" : "!=",
magic2));
errno = EINVAL;
goto fail;
}
/* Is it already in the open list? If so, fail. */
if (tdb_already_open(tdb->device, tdb->inode)) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: "
"%s (%d,%d) is already open in this process\n",
name, (int)tdb->device, (int)tdb->inode));
errno = EBUSY;
goto fail;
}
/*
* We had tdb_mmap(tdb) here before,
* but we need to use tdb_fstat(),
* which is triggered from tdb_oob() before calling tdb_mmap().
* As this skips tdb->hdr_ofs.
*/
tdb->map_size = 0;
ret = tdb_oob(tdb, 0, 1, 0);
if (ret == -1) {
errno = EIO;
goto fail;
}
if (tdb->feature_flags & TDB_FEATURE_FLAG_MUTEX) {
if (!(tdb->flags & TDB_NOLOCK)) {
ret = tdb_mutex_mmap(tdb);
if (ret != 0) {
goto fail;
}
}
}
if (tdb->hash_size > UINT32_MAX/4) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
"hash size %"PRIu32" too large\n", tdb->hash_size));
errno = EINVAL;
goto fail;
}
ret = tdb_oob(tdb, FREELIST_TOP, 4*tdb->hash_size, 1);
if (ret == -1) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
"hash size %"PRIu32" does not fit\n", tdb->hash_size));
errno = EINVAL;
goto fail;
}
if (locked) {
if (tdb_nest_unlock(tdb, ACTIVE_LOCK, F_WRLCK, false) == -1) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: "
"failed to release ACTIVE_LOCK on %s: %s\n",
name, strerror(errno)));
goto fail;
}
}
if (locked || (tdb_flags & TDB_CLEAR_IF_FIRST)) {
/*
* We always need to do this if the CLEAR_IF_FIRST
* flag is set, even if we didn't get the initial
* exclusive lock as we need to let all other users
* know we're using it.
*/
ret = tdb_nest_lock(tdb, ACTIVE_LOCK, F_RDLCK, TDB_LOCK_WAIT);
if (ret == -1) {
goto fail;
}
}
/* if needed, run recovery */
if (tdb_transaction_recover(tdb) == -1) {
goto fail;
}
#ifdef TDB_TRACE
{
char tracefile[strlen(name) + 32];
snprintf(tracefile, sizeof(tracefile),
"%s.trace.%li", name, (long)getpid());
tdb->tracefd = open(tracefile, O_WRONLY|O_CREAT|O_EXCL, 0600);
if (tdb->tracefd >= 0) {
tdb_enable_seqnum(tdb);
tdb_trace_open(tdb, "tdb_open", hash_size, tdb_flags,
open_flags);
} else
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: failed to open trace file %s!\n", tracefile));
}
#endif
internal:
/* Internal (memory-only) databases skip all the code above to
* do with disk files, and resume here by releasing their
* open lock and hooking into the active list. */
if (tdb_nest_unlock(tdb, OPEN_LOCK, F_WRLCK, false) == -1) {
goto fail;
}
tdb->next = tdbs;
tdbs = tdb;
errno = orig_errno;
return tdb;
fail:
{ int save_errno = errno;
if (!tdb)
return NULL;
#ifdef TDB_TRACE
close(tdb->tracefd);
#endif
if (tdb->map_ptr) {
if (tdb->flags & TDB_INTERNAL)
SAFE_FREE(tdb->map_ptr);
else
tdb_munmap(tdb);
}
if (tdb->fd != -1)
if (close(tdb->fd) != 0)
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: failed to close tdb->fd on error!\n"));
SAFE_FREE(tdb->lockrecs);
SAFE_FREE(tdb->name);
SAFE_FREE(tdb);
errno = save_errno;
return NULL;
}
}
/*
* Set the maximum number of dead records per hash chain
*/
_PUBLIC_ void tdb_set_max_dead(struct tdb_context *tdb, int max_dead)
{
tdb->max_dead_records = max_dead;
}
/**
* Close a database.
*
* @returns -1 for error; 0 for success.
**/
_PUBLIC_ int tdb_close(struct tdb_context *tdb)
{
struct tdb_context **i;
int ret = 0;
if (tdb->transaction) {
tdb_transaction_cancel(tdb);
}
tdb_trace(tdb, "tdb_close");
if (tdb->map_ptr) {
if (tdb->flags & TDB_INTERNAL)
SAFE_FREE(tdb->map_ptr);
else
tdb_munmap(tdb);
}
tdb_mutex_munmap(tdb);
SAFE_FREE(tdb->name);
if (tdb->fd != -1) {
ret = close(tdb->fd);
tdb->fd = -1;
}
SAFE_FREE(tdb->lockrecs);
/* Remove from contexts list */
for (i = &tdbs; *i; i = &(*i)->next) {
if (*i == tdb) {
*i = tdb->next;
break;
}
}
#ifdef TDB_TRACE
close(tdb->tracefd);
#endif
memset(tdb, 0, sizeof(*tdb));
SAFE_FREE(tdb);
return ret;
}
/* register a loging function */
_PUBLIC_ void tdb_set_logging_function(struct tdb_context *tdb,
const struct tdb_logging_context *log_ctx)
{
tdb->log = *log_ctx;
}
_PUBLIC_ void *tdb_get_logging_private(struct tdb_context *tdb)
{
return tdb->log.log_private;
}
static int tdb_reopen_internal(struct tdb_context *tdb, bool active_lock)
{
#if !defined(LIBREPLACE_PREAD_NOT_REPLACED) || \
!defined(LIBREPLACE_PWRITE_NOT_REPLACED)
struct stat st;
#endif
if (tdb->flags & TDB_INTERNAL) {
return 0; /* Nothing to do. */
}
if (tdb_have_extra_locks(tdb)) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_reopen: reopen not allowed with locks held\n"));
goto fail;
}
if (tdb->transaction != 0) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_reopen: reopen not allowed inside a transaction\n"));
goto fail;
}
/* If we have real pread & pwrite, we can skip reopen. */
#if !defined(LIBREPLACE_PREAD_NOT_REPLACED) || \
!defined(LIBREPLACE_PWRITE_NOT_REPLACED)
if (tdb_munmap(tdb) != 0) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: munmap failed (%s)\n", strerror(errno)));
goto fail;
}
if (close(tdb->fd) != 0)
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: WARNING closing tdb->fd failed!\n"));
tdb->fd = open(tdb->name, tdb->open_flags & ~(O_CREAT|O_TRUNC), 0);
if (tdb->fd == -1) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: open failed (%s)\n", strerror(errno)));
goto fail;
}
/*
* We only use st.st_dev and st.st_ino from the raw fstat()
* call, everything else needs to use tdb_fstat() in order
* to skip tdb->hdr_ofs!
*/
if (fstat(tdb->fd, &st) != 0) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: fstat failed (%s)\n", strerror(errno)));
goto fail;
}
if (st.st_ino != tdb->inode || st.st_dev != tdb->device) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: file dev/inode has changed!\n"));
goto fail;
}
ZERO_STRUCT(st);
/*
* We had tdb_mmap(tdb) here before,
* but we need to use tdb_fstat(),
* which is triggered from tdb_oob() before calling tdb_mmap().
* As this skips tdb->hdr_ofs.
*/
tdb->map_size = 0;
if (tdb_oob(tdb, 0, 1, 0) != 0) {
goto fail;
}
#endif /* fake pread or pwrite */
/* We may still think we hold the active lock. */
tdb->num_lockrecs = 0;
SAFE_FREE(tdb->lockrecs);
tdb->lockrecs_array_length = 0;
if (active_lock && tdb_nest_lock(tdb, ACTIVE_LOCK, F_RDLCK, TDB_LOCK_WAIT) == -1) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: failed to obtain active lock\n"));
goto fail;
}
return 0;
fail:
tdb_close(tdb);
return -1;
}
/* reopen a tdb - this can be used after a fork to ensure that we have an independent
seek pointer from our parent and to re-establish locks */
_PUBLIC_ int tdb_reopen(struct tdb_context *tdb)
{
bool active_lock;
active_lock = (tdb->flags & (TDB_CLEAR_IF_FIRST|TDB_MUTEX_LOCKING));
return tdb_reopen_internal(tdb, active_lock);
}
/* reopen all tdb's */
_PUBLIC_ int tdb_reopen_all(int parent_longlived)
{
struct tdb_context *tdb;
for (tdb=tdbs; tdb; tdb = tdb->next) {
bool active_lock;
active_lock =
(tdb->flags & (TDB_CLEAR_IF_FIRST|TDB_MUTEX_LOCKING));
/*
* If the parent is longlived (ie. a
* parent daemon architecture), we know
* it will keep it's active lock on a
* tdb opened with CLEAR_IF_FIRST. Thus
* for child processes we don't have to
* add an active lock. This is essential
* to improve performance on systems that
* keep POSIX locks as a non-scalable data
* structure in the kernel.
*/
if (parent_longlived) {
/* Ensure no clear-if-first. */
active_lock = false;
}
if (tdb_reopen_internal(tdb, active_lock) != 0)
return -1;
}
return 0;
}