+
+ /* If we were the tail, off = &head->prev. */
+ if (r->next == 0) {
+ head = tdb_read_off(tdb, b_off);
+ if (TDB_OFF_IS_ERR(head))
+ return head;
+ off = head + offsetof(struct tdb_free_record, magic_and_prev);
+ } else {
+ /* off = &r->next->prev */
+ off = r->next + offsetof(struct tdb_free_record,
+ magic_and_prev);
+ }
+
+#ifdef CCAN_TDB2_DEBUG
+ /* *off == r */
+ if ((tdb_read_off(tdb, off) & TDB_OFF_MASK) != r_off) {
+ return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
+ "remove_from_list:"
+ " %llu bad prev in list %llu",
+ (long long)r_off, (long long)b_off);
+ }
+#endif
+ /* r->next->prev = r->prev */
+ return tdb_write_off(tdb, off, r->magic_and_prev);