return FREELIST_TOP + 4*list;
}
+static struct tdb_lock_type *find_nestlock(struct tdb_context *tdb,
+ tdb_off_t offset)
+{
+ unsigned int i;
+
+ for (i=0; i<tdb->num_lockrecs; i++) {
+ if (tdb->lockrecs[i].off == offset) {
+ return &tdb->lockrecs[i];
+ }
+ }
+ return NULL;
+}
+
/* lock an offset in the database. */
int tdb_nest_lock(struct tdb_context *tdb, uint32_t offset, int ltype,
enum tdb_lock_flags flags)
{
struct tdb_lock_type *new_lck;
- int i;
if (offset >= lock_offset(tdb->header.hash_size)) {
tdb->ecode = TDB_ERR_LOCK;
if (tdb->flags & TDB_NOLOCK)
return 0;
- for (i=0; i<tdb->num_lockrecs; i++) {
- if (tdb->lockrecs[i].off == offset) {
- if (tdb->lockrecs[i].count == 0) {
- /*
- * Can't happen, see tdb_unlock(). It should
- * be an assert.
- */
- TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_lock: "
- "lck->count == 0 for offset %u",
- offset));
- }
- /*
- * Just increment the in-memory struct, posix locks
- * don't stack.
- */
- tdb->lockrecs[i].count++;
- return 0;
- }
+ new_lck = find_nestlock(tdb, offset);
+ if (new_lck) {
+ /*
+ * Just increment the in-memory struct, posix locks
+ * don't stack.
+ */
+ new_lck->count++;
+ return 0;
}
new_lck = (struct tdb_lock_type *)realloc(
return -1;
}
- tdb->num_locks++;
-
tdb->lockrecs[tdb->num_lockrecs].off = offset;
tdb->lockrecs[tdb->num_lockrecs].count = 1;
tdb->lockrecs[tdb->num_lockrecs].ltype = ltype;
- tdb->num_lockrecs += 1;
+ tdb->num_lockrecs++;
return 0;
}
bool mark_lock)
{
int ret = -1;
- int i;
- struct tdb_lock_type *lck = NULL;
+ struct tdb_lock_type *lck;
if (tdb->flags & TDB_NOLOCK)
return 0;
return ret;
}
- for (i=0; i<tdb->num_lockrecs; i++) {
- if (tdb->lockrecs[i].off == offset) {
- lck = &tdb->lockrecs[i];
- break;
- }
- }
-
+ lck = find_nestlock(tdb, offset);
if ((lck == NULL) || (lck->count == 0)) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_unlock: count is 0\n"));
return -1;
} else {
ret = tdb->methods->brunlock(tdb, ltype, offset, 1);
}
- tdb->num_locks--;
/*
* Shrink the array by overwriting the element just unlocked with the
* last array element.
*/
-
- if (tdb->num_lockrecs > 1) {
- *lck = tdb->lockrecs[tdb->num_lockrecs-1];
- }
- tdb->num_lockrecs -= 1;
+ *lck = tdb->lockrecs[--tdb->num_lockrecs];
/*
* We don't bother with realloc when the array shrinks, but if we have
*/
int tdb_transaction_lock(struct tdb_context *tdb, int ltype)
{
- if (tdb->transaction_lock_count > 0) {
- tdb->transaction_lock_count++;
- return 0;
- }
-
- if (tdb->methods->brlock(tdb, ltype, TRANSACTION_LOCK, 1, TDB_LOCK_WAIT) == -1) {
- TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_lock: failed to get transaction lock\n"));
- tdb->ecode = TDB_ERR_LOCK;
- return -1;
- }
- tdb->transaction_lock_count++;
- return 0;
+ return tdb_nest_lock(tdb, TRANSACTION_LOCK, ltype, TDB_LOCK_WAIT);
}
/*
*/
int tdb_transaction_unlock(struct tdb_context *tdb, int ltype)
{
- int ret;
- if (tdb->transaction_lock_count > 1) {
- tdb->transaction_lock_count--;
- return 0;
- }
- ret = tdb->methods->brunlock(tdb, ltype, TRANSACTION_LOCK, 1);
- if (ret == 0) {
- tdb->transaction_lock_count = 0;
- }
- return ret;
+ return tdb_nest_unlock(tdb, TRANSACTION_LOCK, ltype, false);
}
bool tdb_have_extra_locks(struct tdb_context *tdb)
{
+ unsigned int extra = tdb->num_lockrecs;
+
if (tdb->allrecord_lock.count) {
return true;
}
- if (tdb->num_lockrecs) {
- return true;
+
+ /* We always hold the active lock if CLEAR_IF_FIRST. */
+ if (find_nestlock(tdb, ACTIVE_LOCK)) {
+ extra--;
}
- return false;
+
+ /* In a transaction, we expect to hold the transaction lock */
+ if (tdb->transaction && find_nestlock(tdb, TRANSACTION_LOCK)) {
+ extra--;
+ }
+
+ return extra;
}
-/* The transaction code uses this to remove all locks. */
+/* The transaction code uses this to remove all locks. Note that this
+ may include OPEN_LOCK. */
void tdb_release_extra_locks(struct tdb_context *tdb)
{
- unsigned int i;
+ unsigned int i, extra = 0;
if (tdb->allrecord_lock.count != 0) {
tdb_brunlock(tdb, tdb->allrecord_lock.ltype,
}
for (i=0;i<tdb->num_lockrecs;i++) {
- tdb_brunlock(tdb, tdb->lockrecs[i].ltype,
- tdb->lockrecs[i].off, 1);
+ struct tdb_lock_type *lck = &tdb->lockrecs[i];
+
+ /* Don't release transaction or active locks! */
+ if (tdb->transaction && lck->off == TRANSACTION_LOCK) {
+ tdb->lockrecs[extra++] = *lck;
+ } else if (lck->off == ACTIVE_LOCK) {
+ tdb->lockrecs[extra++] = *lck;
+ } else {
+ tdb_brunlock(tdb, lck->ltype, lck->off, 1);
+ }
+ }
+ tdb->num_lockrecs = extra;
+ if (tdb->num_lockrecs == 0) {
+ SAFE_FREE(tdb->lockrecs);
}
- tdb->num_locks = 0;
- tdb->num_lockrecs = 0;
- SAFE_FREE(tdb->lockrecs);
}
projects / ccan / blobdiff