-/*
-URL: svn://svnanon.samba.org/samba/branches/SAMBA_4_0/source/lib/tdb
-Rev: 22080
-Last Changed: 2007-04-03 05:08:18 -0400
+/*
+URL: svn://svnanon.samba.org/samba/branches/SAMBA_4_0/source/lib/tdb/common
+Rev: 23590
+Last Changed Date: 2007-06-22 13:36:10 -0400 (Fri, 22 Jun 2007)
*/
/*
trivial database library - standalone version
#endif
#endif
+typedef int bool;
+
#include "tdb.h"
#ifndef u32
struct tdb_transaction *transaction;
int page_size;
int max_dead_records;
+ bool have_transaction_lock;
};
static int tdb_lock(struct tdb_context *tdb, int list, int ltype);
static int tdb_unlock(struct tdb_context *tdb, int list, int ltype);
static int tdb_brlock(struct tdb_context *tdb, tdb_off_t offset, int rw_type, int lck_type, int probe, size_t len);
+static int tdb_transaction_lock(struct tdb_context *tdb, int ltype);
+static int tdb_transaction_unlock(struct tdb_context *tdb);
static int tdb_brlock_upgrade(struct tdb_context *tdb, tdb_off_t offset, size_t len);
static int tdb_write_lock_record(struct tdb_context *tdb, tdb_off_t off);
static int tdb_write_unlock_record(struct tdb_context *tdb, tdb_off_t off);
struct list_struct *rec);
static void tdb_io_init(struct tdb_context *tdb);
static int tdb_expand(struct tdb_context *tdb, tdb_off_t size);
+static int tdb_rec_free_read(struct tdb_context *tdb, tdb_off_t off,
+ struct list_struct *rec);
/* file: error.c */
/* file: lock.c */
+#define TDB_MARK_LOCK 0x80000000
+
/* a byte range locking function - return 0 on success
this functions locks/unlocks 1 byte at the specified offset.
/* lock a list in the database. list -1 is the alloc list */
-int tdb_lock(struct tdb_context *tdb, int list, int ltype)
+static int _tdb_lock(struct tdb_context *tdb, int list, int ltype, int op)
{
struct tdb_lock_type *new_lck;
int i;
+ bool mark_lock = ((ltype & TDB_MARK_LOCK) == TDB_MARK_LOCK);
+
+ ltype &= ~TDB_MARK_LOCK;
/* a global lock allows us to avoid per chain locks */
if (tdb->global_lock.count &&
/* Since fcntl locks don't nest, we do a lock for the first one,
and simply bump the count for future ones */
- if (tdb->methods->tdb_brlock(tdb,FREELIST_TOP+4*list,ltype,F_SETLKW,
+ if (!mark_lock &&
+ tdb->methods->tdb_brlock(tdb,FREELIST_TOP+4*list, ltype, op,
0, 1)) {
- TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_lock failed on list %d "
- "ltype=%d (%s)\n", list, ltype, strerror(errno)));
return -1;
}
return 0;
}
+/* lock a list in the database. list -1 is the alloc list */
+int tdb_lock(struct tdb_context *tdb, int list, int ltype)
+{
+ int ret;
+ ret = _tdb_lock(tdb, list, ltype, F_SETLKW);
+ if (ret) {
+ TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_lock failed on list %d "
+ "ltype=%d (%s)\n", list, ltype, strerror(errno)));
+ }
+ return ret;
+}
+
+/* lock a list in the database. list -1 is the alloc list. non-blocking lock */
+int tdb_lock_nonblock(struct tdb_context *tdb, int list, int ltype)
+{
+ return _tdb_lock(tdb, list, ltype, F_SETLK);
+}
+
+
/* unlock the database: returns void because it's too late for errors. */
/* changed to return int it may be interesting to know there
has been an error --simo */
int ret = -1;
int i;
struct tdb_lock_type *lck = NULL;
+ bool mark_lock = ((ltype & TDB_MARK_LOCK) == TDB_MARK_LOCK);
+
+ ltype &= ~TDB_MARK_LOCK;
/* a global lock allows us to avoid per chain locks */
if (tdb->global_lock.count &&
* anyway.
*/
- ret = tdb->methods->tdb_brlock(tdb, FREELIST_TOP+4*list, F_UNLCK,
- F_SETLKW, 0, 1);
+ if (mark_lock) {
+ ret = 0;
+ } else {
+ ret = tdb->methods->tdb_brlock(tdb, FREELIST_TOP+4*list, F_UNLCK,
+ F_SETLKW, 0, 1);
+ }
tdb->num_locks--;
/*
return ret;
}
+/*
+ get the transaction lock
+ */
+int tdb_transaction_lock(struct tdb_context *tdb, int ltype)
+{
+ if (tdb->have_transaction_lock || tdb->global_lock.count) {
+ return 0;
+ }
+ if (tdb->methods->tdb_brlock(tdb, TRANSACTION_LOCK, ltype,
+ F_SETLKW, 0, 1) == -1) {
+ TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_lock: failed to get transaction lock\n"));
+ tdb->ecode = TDB_ERR_LOCK;
+ return -1;
+ }
+ tdb->have_transaction_lock = 1;
+ return 0;
+}
+
+/*
+ release the transaction lock
+ */
+int tdb_transaction_unlock(struct tdb_context *tdb)
+{
+ int ret;
+ if (!tdb->have_transaction_lock) {
+ return 0;
+ }
+ ret = tdb->methods->tdb_brlock(tdb, TRANSACTION_LOCK, F_UNLCK, F_SETLKW, 0, 1);
+ if (ret == 0) {
+ tdb->have_transaction_lock = 0;
+ }
+ return ret;
+}
+
+
/* lock/unlock entire database */
-static int _tdb_lockall(struct tdb_context *tdb, int ltype)
+static int _tdb_lockall(struct tdb_context *tdb, int ltype, int op)
{
+ bool mark_lock = ((ltype & TDB_MARK_LOCK) == TDB_MARK_LOCK);
+
+ ltype &= ~TDB_MARK_LOCK;
+
/* There are no locks on read-only dbs */
if (tdb->read_only || tdb->traverse_read)
return TDB_ERRCODE(TDB_ERR_LOCK, -1);
return TDB_ERRCODE(TDB_ERR_LOCK, -1);
}
- if (tdb->methods->tdb_brlock(tdb, FREELIST_TOP, ltype, F_SETLKW,
+ if (!mark_lock &&
+ tdb->methods->tdb_brlock(tdb, FREELIST_TOP, ltype, op,
0, 4*tdb->header.hash_size)) {
- TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_lockall failed (%s)\n", strerror(errno)));
+ if (op == F_SETLKW) {
+ TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_lockall failed (%s)\n", strerror(errno)));
+ }
return -1;
}
return 0;
}
+
+
/* unlock entire db */
static int _tdb_unlockall(struct tdb_context *tdb, int ltype)
{
+ bool mark_lock = ((ltype & TDB_MARK_LOCK) == TDB_MARK_LOCK);
+
+ ltype &= ~TDB_MARK_LOCK;
+
/* There are no locks on read-only dbs */
if (tdb->read_only || tdb->traverse_read) {
return TDB_ERRCODE(TDB_ERR_LOCK, -1);
return 0;
}
- if (tdb->methods->tdb_brlock(tdb, FREELIST_TOP, F_UNLCK, F_SETLKW,
+ if (!mark_lock &&
+ tdb->methods->tdb_brlock(tdb, FREELIST_TOP, F_UNLCK, F_SETLKW,
0, 4*tdb->header.hash_size)) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_unlockall failed (%s)\n", strerror(errno)));
return -1;
/* lock entire database with write lock */
int tdb_lockall(struct tdb_context *tdb)
{
- return _tdb_lockall(tdb, F_WRLCK);
+ return _tdb_lockall(tdb, F_WRLCK, F_SETLKW);
+}
+
+/* lock entire database with write lock - mark only */
+int tdb_lockall_mark(struct tdb_context *tdb)
+{
+ return _tdb_lockall(tdb, F_WRLCK | TDB_MARK_LOCK, F_SETLKW);
+}
+
+/* unlock entire database with write lock - unmark only */
+int tdb_lockall_unmark(struct tdb_context *tdb)
+{
+ return _tdb_unlockall(tdb, F_WRLCK | TDB_MARK_LOCK);
+}
+
+/* lock entire database with write lock - nonblocking varient */
+int tdb_lockall_nonblock(struct tdb_context *tdb)
+{
+ return _tdb_lockall(tdb, F_WRLCK, F_SETLK);
}
/* unlock entire database with write lock */
/* lock entire database with read lock */
int tdb_lockall_read(struct tdb_context *tdb)
{
- return _tdb_lockall(tdb, F_RDLCK);
+ return _tdb_lockall(tdb, F_RDLCK, F_SETLKW);
+}
+
+/* lock entire database with read lock - nonblock varient */
+int tdb_lockall_read_nonblock(struct tdb_context *tdb)
+{
+ return _tdb_lockall(tdb, F_RDLCK, F_SETLK);
}
/* unlock entire database with read lock */
return tdb_lock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK);
}
+/* lock/unlock one hash chain, non-blocking. This is meant to be used
+ to reduce contention - it cannot guarantee how many records will be
+ locked */
+int tdb_chainlock_nonblock(struct tdb_context *tdb, TDB_DATA key)
+{
+ return tdb_lock_nonblock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK);
+}
+
+/* mark a chain as locked without actually locking it. Warning! use with great caution! */
+int tdb_chainlock_mark(struct tdb_context *tdb, TDB_DATA key)
+{
+ return tdb_lock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK | TDB_MARK_LOCK);
+}
+
+/* unmark a chain as locked without actually locking it. Warning! use with great caution! */
+int tdb_chainlock_unmark(struct tdb_context *tdb, TDB_DATA key)
+{
+ return tdb_unlock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK | TDB_MARK_LOCK);
+}
+
int tdb_chainunlock(struct tdb_context *tdb, TDB_DATA key)
{
return tdb_unlock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK);
/*
brlock during a transaction - ignore them
*/
-static int transaction_brlock(struct tdb_context *tdb, tdb_off_t offset,
+static int transaction_brlock(struct tdb_context *tdb, tdb_off_t offset,
int rw_type, int lck_type, int probe, size_t len)
{
return 0;
/* get the transaction write lock. This is a blocking lock. As
discussed with Volker, there are a number of ways we could
make this async, which we will probably do in the future */
- if (tdb_brlock(tdb, TRANSACTION_LOCK, F_WRLCK, F_SETLKW, 0, 1) == -1) {
- TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_start: failed to get transaction lock\n"));
- tdb->ecode = TDB_ERR_LOCK;
+ if (tdb_transaction_lock(tdb, F_WRLCK) == -1) {
SAFE_FREE(tdb->transaction);
return -1;
}
TDB_HASHTABLE_SIZE(tdb)) != 0) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_transaction_start: failed to prime hash table\n"));
tdb->ecode = TDB_ERR_IO;
+ tdb->methods = tdb->transaction->io_methods;
goto fail;
}
fail:
tdb_brlock(tdb, FREELIST_TOP, F_UNLCK, F_SETLKW, 0, 0);
- tdb_brlock(tdb, TRANSACTION_LOCK, F_UNLCK, F_SETLKW, 0, 1);
+ tdb_transaction_unlock(tdb);
SAFE_FREE(tdb->transaction->hash_heads);
SAFE_FREE(tdb->transaction);
return -1;
F_UNLCK,F_SETLKW, 0, 1);
}
tdb->num_locks = 0;
+ tdb->num_lockrecs = 0;
+ SAFE_FREE(tdb->lockrecs);
}
/* restore the normal io methods */
tdb->methods = tdb->transaction->io_methods;
tdb_brlock(tdb, FREELIST_TOP, F_UNLCK, F_SETLKW, 0, 0);
- tdb_brlock(tdb, TRANSACTION_LOCK, F_UNLCK, F_SETLKW, 0, 1);
+ tdb_transaction_unlock(tdb);
SAFE_FREE(tdb->transaction->hash_heads);
SAFE_FREE(tdb->transaction);
/* file: freelist.c */
/* read a freelist record and check for simple errors */
-static int rec_free_read(struct tdb_context *tdb, tdb_off_t off, struct list_struct *rec)
+static int tdb_rec_free_read(struct tdb_context *tdb, tdb_off_t off, struct list_struct *rec)
{
if (tdb->methods->tdb_read(tdb, off, rec, sizeof(*rec),DOCONV()) == -1)
return -1;
if (rec->magic == TDB_MAGIC) {
/* this happens when a app is showdown while deleting a record - we should
not completely fail when this happens */
- TDB_LOG((tdb, TDB_DEBUG_WARNING, "rec_free_read non-free magic 0x%x at offset=%d - fixing\n",
+ TDB_LOG((tdb, TDB_DEBUG_WARNING, "tdb_rec_free_read non-free magic 0x%x at offset=%d - fixing\n",
rec->magic, off));
rec->magic = TDB_FREE_MAGIC;
if (tdb->methods->tdb_write(tdb, off, rec, sizeof(*rec)) == -1)
if (rec->magic != TDB_FREE_MAGIC) {
/* Ensure ecode is set for log fn. */
tdb->ecode = TDB_ERR_CORRUPT;
- TDB_LOG((tdb, TDB_DEBUG_WARNING, "rec_free_read bad magic 0x%x at offset=%d\n",
+ TDB_LOG((tdb, TDB_DEBUG_WARNING, "tdb_rec_free_read bad magic 0x%x at offset=%d\n",
rec->magic, off));
return TDB_ERRCODE(TDB_ERR_CORRUPT, -1);
}
issues when faced with a slowly increasing record size.
*/
while (rec_ptr) {
- if (rec_free_read(tdb, rec_ptr, rec) == -1) {
+ if (tdb_rec_free_read(tdb, rec_ptr, rec) == -1) {
goto fail;
}
}
if (bestfit.rec_ptr != 0) {
- if (rec_free_read(tdb, bestfit.rec_ptr, rec) == -1) {
+ if (tdb_rec_free_read(tdb, bestfit.rec_ptr, rec) == -1) {
goto fail;
}
goto fail;
}
- if (rec_free_read(tdb, rec_ptr, &rec) == -1) {
+ if (tdb_rec_free_read(tdb, rec_ptr, &rec) == -1) {
goto fail;
}
{
struct tdb_traverse_lock tl = { NULL, 0, 0, F_RDLCK };
int ret;
-
+
/* we need to get a read lock on the transaction lock here to
cope with the lock ordering semantics of solaris10 */
- if (tdb->methods->tdb_brlock(tdb, TRANSACTION_LOCK, F_RDLCK, F_SETLKW, 0, 1) == -1) {
- TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_traverse_read: failed to get transaction lock\n"));
- tdb->ecode = TDB_ERR_LOCK;
+ if (tdb_transaction_lock(tdb, F_RDLCK)) {
return -1;
}
ret = tdb_traverse_internal(tdb, fn, private_data, &tl);
tdb->traverse_read--;
- tdb->methods->tdb_brlock(tdb, TRANSACTION_LOCK, F_UNLCK, F_SETLKW, 0, 1);
+ tdb_transaction_unlock(tdb);
return ret;
}
return tdb_traverse_read(tdb, fn, private_data);
}
- if (tdb->methods->tdb_brlock(tdb, TRANSACTION_LOCK, F_WRLCK, F_SETLKW, 0, 1) == -1) {
- TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_traverse: failed to get transaction lock\n"));
- tdb->ecode = TDB_ERR_LOCK;
+ if (tdb_transaction_lock(tdb, F_WRLCK)) {
return -1;
}
ret = tdb_traverse_internal(tdb, fn, private_data, &tl);
- tdb->methods->tdb_brlock(tdb, TRANSACTION_LOCK, F_UNLCK, F_SETLKW, 0, 1);
+ tdb_transaction_unlock(tdb);
return ret;
}
tdb->travlocks.off = tdb->travlocks.hash = 0;
tdb->travlocks.lock_rw = F_RDLCK;
+ /* Grab first record: locks chain and returned record. */
if (tdb_next_lock(tdb, &tdb->travlocks, &rec) <= 0)
return tdb_null;
/* now read the key */
key.dsize = rec.key_len;
key.dptr =tdb_alloc_read(tdb,tdb->travlocks.off+sizeof(rec),key.dsize);
- if (tdb_unlock(tdb, BUCKET(tdb->travlocks.hash), F_WRLCK) != 0)
+
+ /* Unlock the hash chain of the record we just read. */
+ if (tdb_unlock(tdb, tdb->travlocks.hash, tdb->travlocks.lock_rw) != 0)
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_firstkey: error occurred while tdb_unlocking!\n"));
return key;
}
/* Is locked key the old key? If so, traverse will be reliable. */
if (tdb->travlocks.off) {
- if (tdb_lock(tdb,tdb->travlocks.hash,F_WRLCK))
+ if (tdb_lock(tdb,tdb->travlocks.hash,tdb->travlocks.lock_rw))
return tdb_null;
if (tdb_rec_read(tdb, tdb->travlocks.off, &rec) == -1
|| !(k = tdb_alloc_read(tdb,tdb->travlocks.off+sizeof(rec),
SAFE_FREE(k);
return tdb_null;
}
- if (tdb_unlock(tdb, tdb->travlocks.hash, F_WRLCK) != 0) {
+ if (tdb_unlock(tdb, tdb->travlocks.hash, tdb->travlocks.lock_rw) != 0) {
SAFE_FREE(k);
return tdb_null;
}
if (!tdb->travlocks.off) {
/* No previous element: do normal find, and lock record */
- tdb->travlocks.off = tdb_find_lock_hash(tdb, oldkey, tdb->hash_fn(&oldkey), F_WRLCK, &rec);
+ tdb->travlocks.off = tdb_find_lock_hash(tdb, oldkey, tdb->hash_fn(&oldkey), tdb->travlocks.lock_rw, &rec);
if (!tdb->travlocks.off)
return tdb_null;
tdb->travlocks.hash = BUCKET(rec.full_hash);
key.dptr = tdb_alloc_read(tdb, tdb->travlocks.off+sizeof(rec),
key.dsize);
/* Unlock the chain of this new record */
- if (tdb_unlock(tdb, tdb->travlocks.hash, F_WRLCK) != 0)
+ if (tdb_unlock(tdb, tdb->travlocks.hash, tdb->travlocks.lock_rw) != 0)
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_nextkey: WARNING tdb_unlock failed!\n"));
}
/* Unlock the chain of old record */
- if (tdb_unlock(tdb, BUCKET(oldhash), F_WRLCK) != 0)
+ if (tdb_unlock(tdb, BUCKET(oldhash), tdb->travlocks.lock_rw) != 0)
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_nextkey: WARNING tdb_unlock failed!\n"));
return key;
}
/* file: dump.c */
-static tdb_off_t tdb_dump_record(struct tdb_context *tdb, tdb_off_t offset)
+static tdb_off_t tdb_dump_record(struct tdb_context *tdb, int hash,
+ tdb_off_t offset)
{
struct list_struct rec;
tdb_off_t tailer_ofs, tailer;
return 0;
}
- printf(" rec: offset=0x%08x next=0x%08x rec_len=%d key_len=%d data_len=%d full_hash=0x%x magic=0x%x\n",
- offset, rec.next, rec.rec_len, rec.key_len, rec.data_len, rec.full_hash, rec.magic);
+ printf(" rec: hash=%d offset=0x%08x next=0x%08x rec_len=%d "
+ "key_len=%d data_len=%d full_hash=0x%x magic=0x%x\n",
+ hash, offset, rec.next, rec.rec_len, rec.key_len, rec.data_len,
+ rec.full_hash, rec.magic);
tailer_ofs = offset + sizeof(rec) + rec.rec_len - sizeof(tdb_off_t);
printf("hash=%d\n", i);
while (rec_ptr) {
- rec_ptr = tdb_dump_record(tdb, rec_ptr);
+ rec_ptr = tdb_dump_record(tdb, i, rec_ptr);
}
return tdb_unlock(tdb, i, F_WRLCK);
TDB_DATA tdb_null;
/*
- increment the tdb sequence number if the tdb has been opened using
+ non-blocking increment of the tdb sequence number if the tdb has been opened using
the TDB_SEQNUM flag
*/
-static void tdb_increment_seqnum(struct tdb_context *tdb)
+void tdb_increment_seqnum_nonblock(struct tdb_context *tdb)
{
tdb_off_t seqnum=0;
return;
}
- if (tdb_brlock(tdb, TDB_SEQNUM_OFS, F_WRLCK, F_SETLKW, 1, 1) != 0) {
- return;
- }
-
/* we ignore errors from this, as we have no sane way of
dealing with them.
*/
tdb_ofs_read(tdb, TDB_SEQNUM_OFS, &seqnum);
seqnum++;
tdb_ofs_write(tdb, TDB_SEQNUM_OFS, &seqnum);
+}
+
+/*
+ increment the tdb sequence number if the tdb has been opened using
+ the TDB_SEQNUM flag
+*/
+static void tdb_increment_seqnum(struct tdb_context *tdb)
+{
+ if (!(tdb->flags & TDB_SEQNUM)) {
+ return;
+ }
+
+ if (tdb_brlock(tdb, TDB_SEQNUM_OFS, F_WRLCK, F_SETLKW, 1, 1) != 0) {
+ return;
+ }
+
+ tdb_increment_seqnum_nonblock(tdb);
tdb_brlock(tdb, TDB_SEQNUM_OFS, F_UNLCK, F_SETLKW, 1, 1);
}
if (dbuf.dptr == NULL) {
dbuf.dptr = (unsigned char *)malloc(new_dbuf.dsize);
} else {
- dbuf.dptr = (unsigned char *)realloc(dbuf.dptr,
+ unsigned char *new_dptr = (unsigned char *)realloc(dbuf.dptr,
dbuf.dsize + new_dbuf.dsize);
+ if (new_dptr == NULL) {
+ free(dbuf.dptr);
+ }
+ dbuf.dptr = new_dptr;
}
if (dbuf.dptr == NULL) {
return tdb->flags;
}
+
+/*
+ enable sequence number handling on an open tdb
+*/
+void tdb_enable_seqnum(struct tdb_context *tdb)
+{
+ tdb->flags |= TDB_SEQNUM;
+}
+
/* file: open.c */
/* all contexts, to ensure no double-opens (fcntl locks don't nest!) */
OSDN Git Service
