]> git.ozlabs.org Git - ccan/blobdiff - ccan/tdb2/lock.c
tdb2: feature support.
[ccan] / ccan / tdb2 / lock.c
index 3e939c4b8ffe3c04e57a2bf67bdfbec51b3ddf90..b1799a7e1b9aa0ca9ec5652f573ba74ac7019761 100644 (file)
@@ -120,7 +120,7 @@ static int fcntl_unlock(struct tdb_context *tdb, int rw, off_t off, off_t len)
 }
 
 /* a byte range locking function - return 0 on success
-   this functions locks/unlocks 1 byte at the specified offset.
+   this functions locks len bytes at the specified offset.
 
    note that a len of zero means lock to end of file
 */
@@ -264,10 +264,7 @@ enum TDB_ERROR tdb_lock_and_recover(struct tdb_context *tdb)
                tdb_allrecord_unlock(tdb, F_WRLCK);
                return ecode;
        }
-       if (tdb_transaction_recover(tdb) == -1) {
-               ecode = tdb->ecode;
-       }
-
+       ecode = tdb_transaction_recover(tdb);
        tdb_unlock_open(tdb);
        tdb_allrecord_unlock(tdb, F_WRLCK);
 
@@ -333,16 +330,21 @@ static enum TDB_ERROR tdb_nest_lock(struct tdb_context *tdb,
 
        /* First time we grab a lock, perhaps someone died in commit? */
        if (!(flags & TDB_LOCK_NOCHECK)
-           && tdb->num_lockrecs == 0
-           && unlikely(tdb_needs_recovery(tdb))) {
-               tdb_brunlock(tdb, ltype, offset, 1);
-
-               ecode = tdb_lock_and_recover(tdb);
-               if (ecode == TDB_SUCCESS) {
-                       ecode = tdb_brlock(tdb, ltype, offset, 1, flags);
-               }
-               if (ecode != TDB_SUCCESS) {
-                       return ecode;
+           && tdb->num_lockrecs == 0) {
+               tdb_bool_err berr = tdb_needs_recovery(tdb);
+               if (berr != false) {
+                       tdb_brunlock(tdb, ltype, offset, 1);
+
+                       if (berr < 0)
+                               return berr;
+                       ecode = tdb_lock_and_recover(tdb);
+                       if (ecode == TDB_SUCCESS) {
+                               ecode = tdb_brlock(tdb, ltype, offset, 1,
+                                                  flags);
+                       }
+                       if (ecode != TDB_SUCCESS) {
+                               return ecode;
+                       }
                }
        }
 
@@ -448,12 +450,7 @@ enum TDB_ERROR tdb_allrecord_lock(struct tdb_context *tdb, int ltype,
                                  enum tdb_lock_flags flags, bool upgradable)
 {
        enum TDB_ERROR ecode;
-
-       /* FIXME: There are no locks on read-only dbs */
-       if (tdb->read_only) {
-               return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
-                                 "tdb_allrecord_lock: read-only");
-       }
+       tdb_bool_err berr;
 
        if (tdb->allrecord_lock.count
            && (ltype == F_RDLCK || tdb->allrecord_lock.ltype == F_WRLCK)) {
@@ -517,16 +514,21 @@ again:
        tdb->allrecord_lock.off = upgradable;
 
        /* Now check for needing recovery. */
-       if (!(flags & TDB_LOCK_NOCHECK) && unlikely(tdb_needs_recovery(tdb))) {
-               tdb_allrecord_unlock(tdb, ltype);
-               ecode = tdb_lock_and_recover(tdb);
-               if (ecode != TDB_SUCCESS) {
-                       return ecode;
-               }
-               goto again;
-       }
+       if (flags & TDB_LOCK_NOCHECK)
+               return TDB_SUCCESS;
 
-       return TDB_SUCCESS;
+       berr = tdb_needs_recovery(tdb);
+       if (likely(berr == false))
+               return TDB_SUCCESS;
+
+       tdb_allrecord_unlock(tdb, ltype);
+       if (berr < 0)
+               return berr;
+       ecode = tdb_lock_and_recover(tdb);
+       if (ecode != TDB_SUCCESS) {
+               return ecode;
+       }
+       goto again;
 }
 
 enum TDB_ERROR tdb_lock_open(struct tdb_context *tdb, enum tdb_lock_flags flags)