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
/* all contexts, to ensure no double-opens (fcntl locks don't nest!) */
static struct tdb_context *tdbs = NULL;
-
-/* This is based on the hash algorithm from gdbm */
-static unsigned int default_tdb_hash(TDB_DATA *key)
+/* 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)
{
- uint32_t value; /* Used to compute the hash value. */
- uint32_t i; /* Used to cycle through random values. */
+ TDB_DATA hash_key;
+ uint32_t tdb_magic = TDB_MAGIC;
- /* Set the initial value from the key size. */
- for (value = 0x238F13AF * key->dsize, i=0; i < key->dsize; i++)
- value = (value + (key->dptr[i] << (i*5 % 24)));
+ 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);
- return (1103515243 * value + 12345);
-}
+ 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, int hash_size)
struct tdb_header *newdb;
size_t size;
int ret = -1;
- ssize_t written;
/* 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)))
- return TDB_ERRCODE(TDB_ERR_OOM, -1);
+ 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;
+
if (tdb->flags & TDB_INTERNAL) {
tdb->map_size = size;
tdb->map_ptr = (char *)newdb;
/* Don't endian-convert the magic food! */
memcpy(newdb->magic_food, TDB_MAGIC_FOOD, strlen(TDB_MAGIC_FOOD)+1);
/* we still have "ret == -1" here */
- written = write(tdb->fd, newdb, size);
- if (written == size) {
- ret = 0;
- } else if (written != -1) {
- /* call write once again, this usually should return -1 and
- * set errno appropriately */
- size -= written;
- written = write(tdb->fd, newdb+written, size);
- if (written == size) {
+ if (tdb_write_all(tdb->fd, newdb, size))
ret = 0;
- } else if (written >= 0) {
- /* a second incomplete write - we give up.
- * guessing the errno... */
- errno = ENOSPC;
- }
- }
fail:
SAFE_FREE(newdb);
ino_t ino)
{
struct tdb_context *i;
-
+
for (i = tdbs; i; i = i->next) {
if (i->device == device && i->inode == ino) {
return 1;
try to call tdb_error or tdb_errname, just do strerror(errno).
@param name may be NULL for internal databases. */
-struct tdb_context *tdb_open(const char *name, int hash_size, int tdb_flags,
+_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);
{
}
+static bool check_header_hash(struct tdb_context *tdb,
+ bool default_hash, uint32_t *m1, uint32_t *m2)
+{
+ tdb_header_hash(tdb, m1, m2);
+ if (tdb->header.magic1_hash == *m1 &&
+ tdb->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, false, m1, m2);
+}
-struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
+_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)
unsigned char *vp;
uint32_t vertest;
unsigned v;
+ const char *hash_alg;
+ uint32_t magic1, magic2;
if (!(tdb = (struct tdb_context *)calloc(1, sizeof *tdb))) {
/* Can't log this */
}
tdb_io_init(tdb);
tdb->fd = -1;
+#ifdef TDB_TRACE
+ tdb->tracefd = -1;
+#endif
tdb->name = NULL;
tdb->map_ptr = NULL;
tdb->flags = tdb_flags;
tdb->log.log_fn = null_log_fn;
tdb->log.log_private = NULL;
}
- tdb->hash_fn = hash_fn ? hash_fn : default_tdb_hash;
+
+ 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 went 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();
errno = EINVAL;
goto fail;
}
-
+
if (hash_size == 0)
hash_size = DEFAULT_HASH_SIZE;
if ((open_flags & O_ACCMODE) == O_RDONLY) {
tdb->flags &= ~TDB_CLEAR_IF_FIRST;
}
+ 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 (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);
fcntl(tdb->fd, F_SETFD, v | FD_CLOEXEC);
/* ensure there is only one process initialising at once */
- if (tdb->methods->tdb_brlock(tdb, GLOBAL_LOCK, F_WRLCK, F_SETLKW, 0, 1) == -1) {
- TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: failed to get global lock on %s: %s\n",
+ 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) &&
- (locked = (tdb->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_WRLCK, F_SETLK, 0, 1) == 0))) {
+ (locked = (tdb_nest_lock(tdb, ACTIVE_LOCK, F_WRLCK, TDB_LOCK_NOWAIT|TDB_LOCK_PROBE) == 0))) {
open_flags |= O_CREAT;
if (ftruncate(tdb->fd, 0) == -1) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
errno = 0;
if (read(tdb->fd, &tdb->header, sizeof(tdb->header)) != sizeof(tdb->header)
- || strcmp(tdb->header.magic_food, TDB_MAGIC_FOOD) != 0
- || (tdb->header.version != TDB_VERSION
- && !(rev = (tdb->header.version==TDB_BYTEREV(TDB_VERSION))))) {
- /* its not a valid database - possibly initialise it */
+ || strcmp(tdb->header.magic_food, TDB_MAGIC_FOOD) != 0) {
if (!(open_flags & O_CREAT) || tdb_new_database(tdb, hash_size) == -1) {
if (errno == 0) {
- errno = EIO; /* ie bad format or something */
+ errno = EIO; /* ie bad format or something */
}
goto fail;
}
rev = (tdb->flags & TDB_CONVERT);
+ } else if (tdb->header.version != TDB_VERSION
+ && !(rev = (tdb->header.version==TDB_BYTEREV(TDB_VERSION)))) {
+ /* wrong version */
+ errno = EIO;
+ goto fail;
}
vp = (unsigned char *)&tdb->header.version;
vertest = (((uint32_t)vp[0]) << 24) | (((uint32_t)vp[1]) << 16) |
if (fstat(tdb->fd, &st) == -1)
goto fail;
- if (tdb->header.rwlocks != 0) {
+ if (tdb->header.rwlocks != 0 &&
+ tdb->header.rwlocks != TDB_HASH_RWLOCK_MAGIC) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: spinlocks no longer supported\n"));
goto fail;
}
+ if ((tdb->header.magic1_hash == 0) && (tdb->header.magic2_hash == 0)) {
+ /* older TDB without magic hash references */
+ tdb->hash_fn = tdb_old_hash;
+ } else if (!check_header_hash(tdb, !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,
+ tdb->header.magic1_hash,
+ (tdb->header.magic1_hash == magic1) ? "==" : "!=",
+ magic1,
+ tdb->header.magic2_hash,
+ (tdb->header.magic2_hash == magic2) ? "==" : "!=",
+ magic2));
+ errno = EINVAL;
+ goto fail;
+ }
+
/* Is it already in the open list? If so, fail. */
if (tdb_already_open(st.st_dev, st.st_ino)) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: "
goto fail;
}
- if (!(tdb->name = (char *)strdup(name))) {
- errno = ENOMEM;
+ /* Beware truncation! */
+ tdb->map_size = st.st_size;
+ if (tdb->map_size != st.st_size) {
+ /* Ensure ecode is set for log fn. */
+ tdb->ecode = TDB_ERR_IO;
+ TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
+ "len %llu too large!\n", (long long)st.st_size));
+ errno = EIO;
goto fail;
}
- tdb->map_size = st.st_size;
tdb->device = st.st_dev;
tdb->inode = st.st_ino;
tdb_mmap(tdb);
if (locked) {
- if (tdb->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_UNLCK, F_SETLK, 0, 1) == -1) {
+ if (tdb_nest_unlock(tdb, ACTIVE_LOCK, F_WRLCK, false) == -1) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: "
- "failed to take ACTIVE_LOCK on %s: %s\n",
+ "failed to release ACTIVE_LOCK on %s: %s\n",
name, strerror(errno)));
goto fail;
}
if (tdb_flags & TDB_CLEAR_IF_FIRST) {
/* leave this lock in place to indicate it's in use */
- if (tdb->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_RDLCK, F_SETLKW, 0, 1) == -1)
+ if (tdb_nest_lock(tdb, ACTIVE_LOCK, F_RDLCK, TDB_LOCK_WAIT) == -1) {
goto fail;
+ }
}
/* if needed, run recovery */
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
- * global lock and hooking into the active list. */
- if (tdb->methods->tdb_brlock(tdb, GLOBAL_LOCK, F_UNLCK, F_SETLKW, 0, 1) == -1)
+ * 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;
return tdb;
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);
}
- SAFE_FREE(tdb->name);
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
*/
-void tdb_set_max_dead(struct tdb_context *tdb, int max_dead)
+_PUBLIC_ void tdb_set_max_dead(struct tdb_context *tdb, int max_dead)
{
tdb->max_dead_records = max_dead;
}
*
* @returns -1 for error; 0 for success.
**/
-int tdb_close(struct tdb_context *tdb)
+_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)
tdb_munmap(tdb);
}
SAFE_FREE(tdb->name);
- if (tdb->fd != -1)
+ if (tdb->fd != -1) {
ret = close(tdb->fd);
+ tdb->fd = -1;
+ }
SAFE_FREE(tdb->lockrecs);
/* Remove from contexts list */
}
}
+#ifdef TDB_TRACE
+ close(tdb->tracefd);
+#endif
memset(tdb, 0, sizeof(*tdb));
SAFE_FREE(tdb);
}
/* register a loging function */
-void tdb_set_logging_function(struct tdb_context *tdb,
- const struct tdb_logging_context *log_ctx)
+_PUBLIC_ void tdb_set_logging_function(struct tdb_context *tdb,
+ const struct tdb_logging_context *log_ctx)
{
tdb->log = *log_ctx;
}
-void *tdb_get_logging_private(struct tdb_context *tdb)
+_PUBLIC_ void *tdb_get_logging_private(struct tdb_context *tdb)
{
return tdb->log.log_private;
}
-/* 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 */
-int tdb_reopen(struct tdb_context *tdb)
+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->num_locks != 0 || tdb->global_lock.count) {
+ if (tdb_have_extra_locks(tdb)) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_reopen: reopen not allowed with locks held\n"));
goto fail;
}
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;
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: open failed (%s)\n", strerror(errno)));
goto fail;
}
- if ((tdb->flags & TDB_CLEAR_IF_FIRST) &&
- (tdb->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_RDLCK, F_SETLKW, 0, 1) == -1)) {
- TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: failed to obtain active lock\n"));
- goto fail;
- }
if (fstat(tdb->fd, &st) != 0) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: fstat failed (%s)\n", strerror(errno)));
goto fail;
goto fail;
}
tdb_mmap(tdb);
+#endif /* fake pread or pwrite */
+
+ /* We may still think we hold the active lock. */
+ tdb->num_lockrecs = 0;
+ SAFE_FREE(tdb->lockrecs);
+
+ 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;
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)
+{
+ return tdb_reopen_internal(tdb, tdb->flags & TDB_CLEAR_IF_FIRST);
+}
+
/* reopen all tdb's */
-int tdb_reopen_all(int parent_longlived)
+_PUBLIC_ int tdb_reopen_all(int parent_longlived)
{
struct tdb_context *tdb;
for (tdb=tdbs; tdb; tdb = tdb->next) {
+ bool active_lock = (tdb->flags & TDB_CLEAR_IF_FIRST);
+
/*
* If the parent is longlived (ie. a
* parent daemon architecture), we know
*/
if (parent_longlived) {
/* Ensure no clear-if-first. */
- tdb->flags &= ~TDB_CLEAR_IF_FIRST;
+ active_lock = false;
}
- if (tdb_reopen(tdb) != 0)
+ if (tdb_reopen_internal(tdb, active_lock) != 0)
return -1;
}
git.samba.org / ira / wip.git / blobdiff