tdb2: make sure records with extra padding have a 0 byte.

[ccan] / ccan / tdb2 / tdb.c

diff --git a/ccan/tdb2/tdb.c b/ccan/tdb2/tdb.c
index 2315c485eea31be3c40af274243f39cc55f633e0..42e75f9d1840b8f79875f01ac05b6637a6d9f358 100644 (file)
--- 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));
@@ -237,6 +238,13 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
                attr = attr->base.next;
        }
 
+       if (tdb_flags & ~(TDB_INTERNAL | TDB_NOLOCK | TDB_NOMMAP | TDB_CONVERT
+                         | TDB_NOSYNC)) {
+               ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
+                                  "tdb_open: unknown flags %u", tdb_flags);
+               goto fail;
+       }
+
        if ((open_flags & O_ACCMODE) == O_WRONLY) {
                ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
                                   "tdb_open: can't open tdb %s write-only",
@@ -354,6 +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);
@@ -492,6 +510,21 @@ static enum TDB_ERROR replace_data(struct tdb_context *tdb,
        return TDB_SUCCESS;
 }
 
+static enum TDB_ERROR update_data(struct tdb_context *tdb,
+                                 tdb_off_t off,
+                                 struct tdb_data dbuf,
+                                 tdb_len_t extra)
+{
+       enum TDB_ERROR ecode;
+
+       ecode = tdb->methods->twrite(tdb, off, dbuf.dptr, dbuf.dsize);
+       if (ecode == TDB_SUCCESS && extra) {
+               /* Put a zero in; future versions may append other data. */
+               ecode = tdb->methods->twrite(tdb, off + dbuf.dsize, "", 1);
+       }
+       return ecode;
+}
+
 enum TDB_ERROR tdb_store(struct tdb_context *tdb,
                         struct tdb_data key, struct tdb_data dbuf, int flag)
 {
@@ -524,11 +557,10 @@ enum TDB_ERROR tdb_store(struct tdb_context *tdb,
                                if (ecode != TDB_SUCCESS) {
                                        goto out;
                                }
-                               ecode = tdb->methods->twrite(tdb,
-                                                            off + sizeof(rec)
-                                                            + key.dsize,
-                                                            dbuf.dptr,
-                                                            dbuf.dsize);
+                               ecode = update_data(tdb,
+                                                   off + sizeof(rec)
+                                                   + key.dsize, dbuf,
+                                                   old_room - dbuf.dsize);
                                if (ecode != TDB_SUCCESS) {
                                        goto out;
                                }
@@ -584,8 +616,8 @@ enum TDB_ERROR tdb_append(struct tdb_context *tdb,
                        }
 
                        off += sizeof(rec) + key.dsize + old_dlen;
-                       ecode = tdb->methods->twrite(tdb, off, dbuf.dptr,
-                                                    dbuf.dsize);
+                       ecode = update_data(tdb, off, dbuf,
+                                           rec_extra_padding(&rec));
                        goto out;
                }