summaryrefslogtreecommitdiffstats
path: root/common/open.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 16:49:38 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 16:49:38 +0000
commitbd8128271ad96c97ddaf5c86915a981ddbff86c6 (patch)
tree19fb138628afa53c660a2db82488d0b703a52fa7 /common/open.c
parentInitial commit. (diff)
downloadtdb-upstream.tar.xz
tdb-upstream.zip
Adding upstream version 1.4.10.upstream/1.4.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'common/open.c')
-rw-r--r--common/open.c968
1 files changed, 968 insertions, 0 deletions
diff --git a/common/open.c b/common/open.c
new file mode 100644
index 0000000..3fa7ce1
--- /dev/null
+++ b/common/open.c
@@ -0,0 +1,968 @@
+ /*
+ 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 paths
+ * 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)
+ /*
+ * Call strncmp() rather than strcmp() in case header.magic_food is
+ * not zero‐terminated. We’re still checking the full string for
+ * equality, as tdb_header::magic_food is larger than
+ * TDB_MAGIC_FOOD.
+ */
+ || strncmp(header.magic_food, TDB_MAGIC_FOOD, sizeof(header.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 logging 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;
+}