X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb2%2Ftdb.c;h=4ffcebf56150bffe381018b4f401aa5503455196;hp=ce431208bf4cb4fa28d09f9158c7fb02c93d7d37;hb=2b5cb9bd6be4e61870ba7a400d1a9d91c5933371;hpb=a0e0927e1f34d80fd4d4ee2d68fa2acb94ae9eb2;ds=sidebyside

diff --git a/ccan/tdb2/tdb.c b/ccan/tdb2/tdb.c
index ce431208..4ffcebf5 100644
--- a/ccan/tdb2/tdb.c
+++ b/ccan/tdb2/tdb.c
@@ -112,6 +112,7 @@ static enum TDB_ERROR tdb_new_database(struct tdb_context *tdb,
 					 newdb.hdr.hash_seed,
 					 tdb->hash_priv);
 	newdb.hdr.recovery = 0;
+	newdb.hdr.features_used = newdb.hdr.features_offered = TDB_FEATURE_MASK;
 	memset(newdb.hdr.reserved, 0, sizeof(newdb.hdr.reserved));
 	/* Initial hashes are empty. */
 	memset(newdb.hdr.hashtable, 0, sizeof(newdb.hdr.hashtable));
@@ -361,6 +362,16 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 		goto fail;
 	}
 
+	/* Clear any features we don't understand. */
+ 	if ((open_flags & O_ACCMODE) != O_RDONLY) {
+		hdr.features_used &= TDB_FEATURE_MASK;
+		if (tdb_write_convert(tdb, offsetof(struct tdb_header,
+						    features_used),
+				      &hdr.features_used,
+				      sizeof(hdr.features_used)) == -1)
+			goto fail;
+	}
+
 	tdb->device = st.st_dev;
 	tdb->inode = st.st_ino;
 	tdb_unlock_open(tdb);