tdb2: make head of free list point to last entry.

[ccan] / ccan / tdb2 / check.c

diff --git a/ccan/tdb2/check.c b/ccan/tdb2/check.c
index ad736c6829a7a5d6d64297553235d892dfad61aa..ab6621ea85b4596aa192c3b53a9dc1aab73de366 100644 (file)
--- a/ccan/tdb2/check.c
+++ b/ccan/tdb2/check.c
@@ -492,7 +492,7 @@ static enum TDB_ERROR check_free(struct tdb_context *tdb,
                                  (long long)off,
                                  bucket, size_to_bucket(frec_len(frec)));
        }
-       if (prev != frec_prev(frec)) {
+       if (prev && prev != frec_prev(frec)) {
                return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
                                  "tdb_check: offset %llu bad prev"
                                  " (%llu vs %llu)",
@@ -528,11 +528,13 @@ static enum TDB_ERROR check_free_table(struct tdb_context *tdb,
        }
 
        for (i = 0; i < TDB_FREE_BUCKETS; i++) {
-               tdb_off_t off, prev = 0, *p;
+               tdb_off_t off, prev = 0, *p, first = 0;
                struct tdb_free_record f;
 
                h = bucket_off(ftable_off, i);
                for (off = tdb_read_off(tdb, h); off; off = f.next) {
+                       if (!first)
+                               first = off;
                        if (TDB_OFF_IS_ERR(off)) {
                                return off;
                        }
@@ -559,6 +561,18 @@ static enum TDB_ERROR check_free_table(struct tdb_context *tdb,
                        (*num_found)++;
                        prev = off;
                }
+
+               if (first) {
+                       /* Now we can check first back pointer. */
+                       ecode = tdb_read_convert(tdb, first, &f, sizeof(f));
+                       if (ecode != TDB_SUCCESS) {
+                               return ecode;
+                       }
+                       ecode = check_free(tdb, first, &f, prev, ftable_num, i);
+                       if (ecode != TDB_SUCCESS) {
+                               return ecode;
+                       }
+               }
        }
        return TDB_SUCCESS;
 }