#include "tdb_private.h"
+#define TDB_MARK_LOCK 0x80000000
+
void tdb_setalarm_sigptr(struct tdb_context *tdb, volatile sig_atomic_t *ptr)
{
tdb->interrupt_sig_ptr = ptr;
/* 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);
git.samba.org / samba.git / blobdiff