tdb: handle processes dying during transaction commit.
[ccan] / ccan / tdb / transaction.c
index 9cbbcc9087fe1d441c4a829b7c121d560d57146a..11194773647e255f1a7c8743cd69d5c85bfeda59 100644 (file)
@@ -1194,3 +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);
+}