diff options
Diffstat (limited to 'bundled/tdb/common/open.c')
-rw-r--r-- | bundled/tdb/common/open.c | 543 |
1 files changed, 0 insertions, 543 deletions
diff --git a/bundled/tdb/common/open.c b/bundled/tdb/common/open.c deleted file mode 100644 index 7687ff6e..00000000 --- a/bundled/tdb/common/open.c +++ /dev/null @@ -1,543 +0,0 @@ - /* - 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; - - -/* This is based on the hash algorithm from gdbm */ -static unsigned int default_tdb_hash(TDB_DATA *key) -{ - uint32_t value; /* Used to compute the hash value. */ - uint32_t i; /* Used to cycle through random values. */ - - /* 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))); - - return (1103515243 * value + 12345); -} - - -/* 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; - - /* 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; - if (tdb->flags & TDB_INTERNAL) { - tdb->map_size = size; - tdb->map_ptr = (char *)newdb; - memcpy(&tdb->header, newdb, sizeof(tdb->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; - - /* This creates an endian-converted header, as if read from disk */ - CONVERT(*newdb); - memcpy(&tdb->header, newdb, sizeof(tdb->header)); - /* 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 */ - if (tdb_write_all(tdb->fd, newdb, size)) - 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. */ -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, ...) -{ -} - - -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) -{ - struct tdb_context *tdb; - struct stat st; - int rev = 0, locked = 0; - unsigned char *vp; - uint32_t vertest; - unsigned v; - - if (!(tdb = (struct tdb_context *)calloc(1, sizeof *tdb))) { - /* Can't log this */ - errno = ENOMEM; - goto fail; - } - 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->open_flags = open_flags; - if (log_ctx) { - tdb->log = *log_ctx; - } else { - tdb->log.log_fn = null_log_fn; - tdb->log.log_private = NULL; - } - tdb->hash_fn = hash_fn ? hash_fn : default_tdb_hash; - - /* 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; - } - - 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; - } - - /* - * 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, hash_size) != 0) { - TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: tdb_new_database failed!")); - goto fail; - } - 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) && - (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: " - "failed to truncate %s: %s\n", - name, strerror(errno))); - goto fail; /* errno set by ftruncate */ - } - } - - errno = 0; - if (read(tdb->fd, &tdb->header, sizeof(tdb->header)) != sizeof(tdb->header) - || 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 */ - } - 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) | - (((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(&tdb->header, sizeof(tdb->header)); - } - if (fstat(tdb->fd, &st) == -1) - goto fail; - - if (tdb->header.rwlocks != 0) { - TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: spinlocks no longer supported\n")); - 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: " - "%s (%d,%d) is already open in this process\n", - name, (int)st.st_dev, (int)st.st_ino)); - errno = EBUSY; - goto fail; - } - - if (!(tdb->name = (char *)strdup(name))) { - errno = ENOMEM; - 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_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; - } - - } - - /* 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. */ - - if (tdb_flags & TDB_CLEAR_IF_FIRST) { - /* leave this lock in place to indicate it's in use */ - if (tdb_nest_lock(tdb, ACTIVE_LOCK, F_RDLCK, TDB_LOCK_WAIT) == -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; - 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); - } - 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); - 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) -{ - tdb->max_dead_records = max_dead; -} - -/** - * Close a database. - * - * @returns -1 for error; 0 for success. - **/ -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); - } - 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 */ -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) -{ - 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; - } - 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; - } - 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; - -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 */ -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) -{ - 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 - * 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; -} |