Import 470750fa2e3cf987f10de48451b1ee13aab03907 from ctdb:

[ccan] / ccan / tdb / tdb.c

diff --git a/ccan/tdb/tdb.c b/ccan/tdb/tdb.c
index 25f3cad6f83e0cacff151c677c6acde7ba41a85b..a09d567c45dc4b74391f6dabdff1cbee9e90757e 100644 (file)
--- a/ccan/tdb/tdb.c
+++ b/ccan/tdb/tdb.c
@@ -122,6 +122,7 @@ tdb_off_t tdb_find_lock_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t has
        return rec_ptr;
 }
 
+static TDB_DATA _tdb_fetch(struct tdb_context *tdb, TDB_DATA key);
 
 /* update an entry in place - this only works if the new data size
    is <= the old data size and the key exists.
@@ -136,6 +137,25 @@ static int tdb_update_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t hash,
        if (!(rec_ptr = tdb_find(tdb, key, hash, &rec)))
                return -1;
 
+       /* it could be an exact duplicate of what is there - this is
+        * surprisingly common (eg. with a ldb re-index). */
+       if (rec.key_len == key.dsize && 
+           rec.data_len == dbuf.dsize &&
+           rec.full_hash == hash) {
+               TDB_DATA data = _tdb_fetch(tdb, key);
+               if (data.dsize == dbuf.dsize &&
+                   memcmp(data.dptr, dbuf.dptr, data.dsize) == 0) {
+                       if (data.dptr) {
+                               free(data.dptr);
+                       }
+                       return 0;
+               }
+               if (data.dptr) {
+                       free(data.dptr);
+               }
+       }
+        
+
        /* must be long enough key, data and tailer */
        if (rec.rec_len < key.dsize + dbuf.dsize + sizeof(tdb_off_t)) {
                tdb->ecode = TDB_SUCCESS; /* Not really an error */