make find_pack_revindex() aware of the nasty world

It currently calls die() whenever given offset is not found thinking
that such thing should never happen.  But this offset may come from a
corrupted pack whych _could_ happen and not be found.  Callers should
deal with this possibility gracefully instead.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c
index c05fb944b0e5d4d26cb2ba1995a787f08d5228ad..04a5a55ef94d411c99287e9c9ac5c75f73051e16 100644 (file)
--- a/builtin-pack-objects.c
+++ b/builtin-pack-objects.c
@@ -1053,6 +1053,8 @@ static void check_object(struct object_entry *entry)
                        if (reuse_delta && !entry->preferred_base) {
                                struct revindex_entry *revidx;
                                revidx = find_pack_revindex(p, ofs);
+                               if (!revidx)
+                                       goto give_up;
                                base_ref = nth_packed_object_sha1(p, revidx->nr);
                        }
                        entry->in_pack_header_size = used + used_0;

diff --git a/pack-revindex.c b/pack-revindex.c
index 6096b6224ad551086afa346617eb714c15a51f78..1de53c8934c03b46604e94cbf4237ad5ffc57f83 100644 (file)
--- a/pack-revindex.c
+++ b/pack-revindex.c
@@ -140,7 +140,8 @@ struct revindex_entry *find_pack_revindex(struct packed_git *p, off_t ofs)
                else
                        lo = mi + 1;
        } while (lo < hi);
-       die("internal error: pack revindex corrupt");
+       error("bad offset for revindex");
+       return NULL;
 }
 
 void discard_revindex(void)

diff --git a/sha1_file.c b/sha1_file.c
index 384a43044e789612446cf1c6cb31fdf0dd037105..9ce1df0cff4aeaf5f2c3877980afe3fea99e7344 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1388,9 +1388,12 @@ static int packed_delta_info(struct packed_git *p,
                return OBJ_BAD;
        type = packed_object_info(p, base_offset, NULL);
        if (type <= OBJ_NONE) {
-               struct revindex_entry *revidx = find_pack_revindex(p, base_offset);
-               const unsigned char *base_sha1 =
-                                       nth_packed_object_sha1(p, revidx->nr);
+               struct revindex_entry *revidx;
+               const unsigned char *base_sha1;
+               revidx = find_pack_revindex(p, base_offset);
+               if (!revidx)
+                       return OBJ_BAD;
+               base_sha1 = nth_packed_object_sha1(p, revidx->nr);
                mark_bad_packed_object(p, base_sha1);
                type = sha1_object_info(base_sha1, NULL);
                if (type <= OBJ_NONE)
@@ -1682,9 +1685,12 @@ static void *unpack_delta_entry(struct packed_git *p,
                 * This is costly but should happen only in the presence
                 * of a corrupted pack, and is better than failing outright.
                 */
-               struct revindex_entry *revidx = find_pack_revindex(p, base_offset);
-               const unsigned char *base_sha1 =
-                                       nth_packed_object_sha1(p, revidx->nr);
+               struct revindex_entry *revidx;
+               const unsigned char *base_sha1;
+               revidx = find_pack_revindex(p, base_offset);
+               if (!revidx)
+                       return NULL;
+               base_sha1 = nth_packed_object_sha1(p, revidx->nr);
                error("failed to read delta base object %s"
                      " at offset %"PRIuMAX" from %s",
                      sha1_to_hex(base_sha1), (uintmax_t)base_offset,