tdb/common/open.c

ソースコードを見る。

関数
static unsigned int	default_tdb_hash (TDB_DATA *key)
static int	tdb_new_database (struct tdb_context *tdb, int hash_size)
static int	tdb_already_open (dev_t device, ino_t ino)
tdb_context *	tdb_open (const char *name, int hash_size, int tdb_flags, int open_flags, mode_t mode)
static void	null_log_fn (struct tdb_context *tdb, enum tdb_debug_level level, const char *fmt,...) PRINTF_ATTRIBUTE(3
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)
void	tdb_set_max_dead (struct tdb_context *tdb, int max_dead)
int	tdb_close (struct tdb_context *tdb)
	Close a database.
void	tdb_set_logging_function (struct tdb_context *tdb, const struct tdb_logging_context *log_ctx)
void *	tdb_get_logging_private (struct tdb_context *tdb)
int	tdb_reopen (struct tdb_context *tdb)
int	tdb_reopen_all (int parent_longlived)
変数
static struct tdb_context *	tdbs = NULL

---

関数

static unsigned int default_tdb_hash

(

TDB_DATA *

key

)

[static]

open.c の 36 行で定義されています。

参照先 TDB_DATA::dptr・TDB_DATA::dsize.

参照元 tdb_open_ex().

{
        u32 value;      /* Used to compute the hash value.  */
        u32   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);  
}

static int tdb_new_database	(	struct tdb_context *	tdb,
		int	hash_size
	)			[static]

open.c の 50 行で定義されています。

参照先 errno・tdb_context::fd・tdb_context::flags・tdb_header::hash_size・tdb_context::header・tdb_header::magic_food・tdb_context::map_ptr・tdb_context::map_size・size・tdb・TDB_ERR_OOM・tdb_header::version.

参照元 tdb_open_ex().

{
        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);

        /* 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 */
        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) {
                        ret = 0;
                } else if (written >= 0) {
                        /* a second incomplete write - we give up.
                         * guessing the errno... */
                        errno = ENOSPC;
                }
        }

  fail:
        SAFE_FREE(newdb);
        return ret;
}

static int tdb_already_open	(	dev_t	device,
		ino_t	ino
	)			[static]

open.c の 109 行で定義されています。

参照先 tdb_context::device・tdb_context::inode・tdb_context::next・tdbs.

参照元 tdb_open_ex().

{
        struct tdb_context *i;
        
        for (i = tdbs; i; i = i->next) {
                if (i->device == device && i->inode == ino) {
                        return 1;
                }
        }

        return 0;
}

struct tdb_context* tdb_open	(	const char *	name,
		int	hash_size,
		int	tdb_flags,
		int	open_flags,
		mode_t	mode
	)

open.c の 133 行で定義されています。

参照先 tdb_open_ex().

参照元 backup_tdb()・create_tdb()・dump_tdb()・hash_a_service()・main()・move_rec()・open_tdb()・py_tdb_open()・smb_share_mode_db_open()・tdb_validate_freelist()・torture_mangle()・verify_tdb().

{
        return tdb_open_ex(name, hash_size, tdb_flags, open_flags, mode, NULL, NULL);
}

static void static void null_log_fn	(	struct tdb_context *	tdb,
		enum tdb_debug_level	level,
		const char *	fmt,
			...
	)			[static]

open.c の 141 行で定義されています。

参照元 tdb_open_ex().

{
}

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
	)

open.c の 146 行で定義されています。

参照先 default_tdb_hash()・errno・tdb_logging_context::log_fn・null_log_fn()・strdup()・strerror()・tdb・tdb_already_open()・tdb_convert()・TDB_DEBUG_ERROR・TDB_DEBUG_FATAL・TDB_DEBUG_WARNING・tdb_io_init()・tdb_mmap()・tdb_munmap()・tdb_new_database()・tdb_transaction_recover()・tdbs.

参照元 main()・mangle_hash_init()・reset_stat_cache()・tdb_open()・tdb_open_log().

{
        struct tdb_context *tdb;
        struct stat st;
        int rev = 0, locked = 0;
        unsigned char *vp;
        u32 vertest;

        if (!(tdb = (struct tdb_context *)calloc(1, sizeof *tdb))) {
                /* Can't log this */
                errno = ENOMEM;
                goto fail;
        }
        tdb_io_init(tdb);
        tdb->fd = -1;
        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;
        }

        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;
        }

        /* 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) */
        }

        /* 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",
                         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) &&
            (locked = (tdb->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_WRLCK, F_SETLK, 0, 1) == 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
            || (tdb->header.version != TDB_VERSION
                && !(rev = (tdb->header.version==TDB_BYTEREV(TDB_VERSION))))) {
                /* its not a valid database - possibly initialise it */
                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);
        }
        vp = (unsigned char *)&tdb->header.version;
        vertest = (((u32)vp[0]) << 24) | (((u32)vp[1]) << 16) |
                  (((u32)vp[2]) << 8) | (u32)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->max_dead_records = 0;
        tdb_mmap(tdb);
        if (locked) {
                if (tdb->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_UNLCK, F_SETLK, 0, 1) == -1) {
                        TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: "
                                 "failed to take 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->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_RDLCK, F_SETLKW, 0, 1) == -1)
                        goto fail;
        }

        /* if needed, run recovery */
        if (tdb_transaction_recover(tdb) == -1) {
                goto fail;
        }

 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)
                goto fail;
        tdb->next = tdbs;
        tdbs = tdb;
        return tdb;

 fail:
        { int save_errno = errno;

        if (!tdb)
                return NULL;
        
        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);
        errno = save_errno;
        return NULL;
        }
}

void tdb_set_max_dead	(	struct tdb_context *	tdb,
		int	max_dead
	)

open.c の 346 行で定義されています。

参照先 tdb_context::max_dead_records・tdb.

参照元 brl_init()・locking_init()・message_init().

{
        tdb->max_dead_records = max_dead;
}

int tdb_close

(

struct tdb_context *

tdb

)

Close a database.

戻り値:

-1 for error; 0 for success.

open.c の 356 行で定義されています。

参照先 tdb_context::fd・tdb_context::flags・tdb_context::lockrecs・tdb_context::map_ptr・tdb_context::name・tdb_context::next・tdb・tdb_munmap()・tdb_transaction_cancel()・tdbs・tdb_context::transaction.

参照元 _reg_perfcount_get_counter_data()・_reg_perfcount_init_data_block_perf()・backup_tdb()・brl_shutdown()・close_all_print_db()・create_tdb()・do_daemon_stack_trace()・do_winbind_offline()・do_winbind_online()・elog_close_tdb()・gencache_shutdown()・idmap_cache_destructor()・idmap_tdb_convert()・idmap_tdb_open_db()・idmap_tdb_tdb_close()・initialize_winbindd_cache()・lang_tdb_init()・locking_end()・login_cache_shutdown()・main()・move_rec()・net_idmap_dump()・net_status_sessions()・net_status_shares()・net_status_shares_parseable()・netsamlogon_cache_shutdown()・netsamlogon_clear_cached_user()・nt_printing_init()・open_schannel_session_store()・open_tdb()・posix_locking_end()・py_tdb_close()・receive_unexpected()・reg_perfcount_get_base_index()・reg_perfcount_get_counter_help()・reg_perfcount_get_counter_names()・reg_perfcount_get_perf_data_block()・regdb_close()・reset_stat_cache()・secrets_restore_schannel_session_info()・secrets_store_schannel_session_info()・send_message()・send_repl_message()・send_sync_message()・smb_share_mode_db_close()・status_page()・tdb_hnd_dealloc()・tdb_reopen()・tdb_validate_freelist()・tdb_wrap_destructor()・tdbsam_close()・tdbsam_new_rid()・tdbsam_open()・verify_tdb()・wcache_flush_cache().

{
        struct tdb_context **i;
        int ret = 0;

        if (tdb->transaction) {
                tdb_transaction_cancel(tdb);
        }

        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);
        SAFE_FREE(tdb->lockrecs);

        /* Remove from contexts list */
        for (i = &tdbs; *i; i = &(*i)->next) {
                if (*i == tdb) {
                        *i = tdb->next;
                        break;
                }
        }

        memset(tdb, 0, sizeof(*tdb));
        SAFE_FREE(tdb);

        return ret;
}

void tdb_set_logging_function	(	struct tdb_context *	tdb,
		const struct tdb_logging_context *	log_ctx
	)

open.c の 391 行で定義されています。

参照先 tdb_context::log・tdb.

{
        tdb->log = *log_ctx;
}

void* tdb_get_logging_private

(

struct tdb_context *

tdb

)

open.c の 397 行で定義されています。

参照先 tdb_context::log・tdb_logging_context::log_private・tdb.

{
        return tdb->log.log_private;
}

int tdb_reopen

(

struct tdb_context *

tdb

)

open.c の 404 行で定義されています。

参照先 tdb_lock_type::count・tdb_context::device・errno・tdb_context::fd・tdb_context::flags・tdb_context::global_lock・tdb_context::inode・tdb_context::methods・tdb_context::name・tdb_context::num_locks・tdb_context::open_flags・strerror()・tdb・tdb_methods::tdb_brlock・tdb_close()・TDB_DEBUG_ERROR・TDB_DEBUG_FATAL・tdb_mmap()・tdb_munmap()・tdb_context::transaction.

参照元 tdb_reopen_all()・wins_write_database().

{
        struct stat st;

        if (tdb->flags & TDB_INTERNAL) {
                return 0; /* Nothing to do. */
        }

        if (tdb->num_locks != 0 || tdb->global_lock.count) {
                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 (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 ((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;
        }
        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);

        return 0;

fail:
        tdb_close(tdb);
        return -1;
}

int tdb_reopen_all

(

int

parent_longlived

)

open.c の 456 行で定義されています。

参照先 tdb_context::flags・tdb_context::next・tdb・tdb_reopen()・tdbs.

参照元 addrec_db()・fork_child_dc_connect()・fork_domain_child()・open_sockets_smbd().

{
        struct tdb_context *tdb;

        for (tdb=tdbs; tdb; tdb = tdb->next) {
                /*
                 * 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. */
                        tdb->flags &= ~TDB_CLEAR_IF_FIRST;
                }

                if (tdb_reopen(tdb) != 0)
                        return -1;
        }

        return 0;
}

---

変数

struct tdb_context* tdbs = NULL [static]

open.c の 32 行で定義されています。

参照元 tdb_already_open()・tdb_close()・tdb_open_ex()・tdb_reopen_all().

---