X-Git-Url: https://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb2%2Ftraverse.c;h=410054d7947a704407dbf3c559a569d22ea27a87;hp=66319dd56764d823dfca54544cfd2ee0d22aea03;hb=d1cea3ebf96f61b5bbac1e74975700770e06add6;hpb=6804501c350181dea8f531142b28c620b70edbd9

diff --git a/ccan/tdb2/traverse.c b/ccan/tdb2/traverse.c
index 66319dd5..410054d7 100644
--- a/ccan/tdb2/traverse.c
+++ b/ccan/tdb2/traverse.c
@@ -56,3 +56,41 @@ int64_t tdb_traverse_read(struct tdb_context *tdb,
 	tdb->read_only = was_ro;
 	return ret;
 }
+
+TDB_DATA tdb_firstkey(struct tdb_context *tdb)
+{
+	struct traverse_info tinfo;
+	struct tdb_data k;
+	switch (first_in_hash(tdb, F_RDLCK, &tinfo, &k, NULL)) {
+	case 1:
+		return k;
+	case 0:
+		tdb->ecode = TDB_SUCCESS;
+		/* Fall thru... */
+	default:
+		return tdb_null;
+	}
+}		
+
+/* We lock twice, not very efficient.  We could keep last key & tinfo cached. */
+TDB_DATA tdb_nextkey(struct tdb_context *tdb, TDB_DATA key)
+{
+	struct traverse_info tinfo;
+	struct hash_info h;
+	struct tdb_used_record rec;
+
+	tinfo.prev = find_and_lock(tdb, key, F_RDLCK, &h, &rec, &tinfo);
+	if (unlikely(tinfo.prev == TDB_OFF_ERR))
+		return tdb_null;
+	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_RDLCK);
+
+	switch (next_in_hash(tdb, F_RDLCK, &tinfo, &key, NULL)) {
+	case 1:
+		return key;
+	case 0:
+		tdb->ecode = TDB_SUCCESS;
+		/* Fall thru... */
+	default:
+		return tdb_null;
+	}
+}