tdb: handle processes dying during transaction commit.
[ccan] / ccan / tdb / transaction.c
index 6b539d4045ee6ef2e91f7943387e2492ffa681ad..11194773647e255f1a7c8743cd69d5c85bfeda59 100644 (file)
@@ -408,33 +408,12 @@ static int transaction_expand_file(struct tdb_context *tdb, tdb_off_t size,
        return 0;
 }
 
-/*
-  brlock during a transaction - ignore them
-*/
-static int transaction_brlock(struct tdb_context *tdb,
-                             int rw_type, tdb_off_t offset, size_t len,
-                             enum tdb_lock_flags flags)
-{
-       /* FIXME: We actually grab the open lock during a transaction. */
-       if (offset == OPEN_LOCK)
-               return tdb_brlock(tdb, rw_type, offset, len, flags);
-       return 0;
-}
-
-static int transaction_brunlock(struct tdb_context *tdb,
-                               int rw_type, tdb_off_t offset, size_t len)
-{
-       return 0;
-}
-
 static const struct tdb_methods transaction_methods = {
        transaction_read,
        transaction_write,
        transaction_next_hash_chain,
        transaction_oob,
        transaction_expand_file,
-       transaction_brlock,
-       transaction_brunlock
 };
 
 /*
@@ -1215,3 +1194,28 @@ int tdb_transaction_recover(struct tdb_context *tdb)
        /* all done */
        return 0;
 }
+
+/* Any I/O failures we say "needs recovery". */
+bool tdb_needs_recovery(struct tdb_context *tdb)
+{
+       tdb_off_t recovery_head;
+       struct tdb_record rec;
+
+       /* find the recovery area */
+       if (tdb_ofs_read(tdb, TDB_RECOVERY_HEAD, &recovery_head) == -1) {
+               return true;
+       }
+
+       if (recovery_head == 0) {
+               /* we have never allocated a recovery record */
+               return false;
+       }
+
+       /* read the recovery record */
+       if (tdb->methods->tdb_read(tdb, recovery_head, &rec,
+                                  sizeof(rec), DOCONV()) == -1) {
+               return true;
+       }
+
+       return (rec.magic == TDB_RECOVERY_MAGIC);
+}