pack-objects: fix use of use_pack().

The code calls use_pack() to make that the variably encoded
offset fits in the mmap'ed window, but it forgot that the
operation gives the pointer to the beginning of the asked
region.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c
index e9a1804fa8e44c02fce844c77665eb939b386d19..42dd8c87a255b81fcc6306ba1ef4bb01dd8dce90 100644 (file)
--- a/builtin-pack-objects.c
+++ b/builtin-pack-objects.c
@@ -1003,6 +1003,7 @@ static void check_object(struct object_entry *entry)
                if (!no_reuse_delta) {
                        unsigned char c, *base_name;
                        unsigned long ofs;
+                       unsigned long used_0;
                        /* there is at least 20 bytes left in the pack */
                        switch (entry->in_pack_type) {
                        case OBJ_REF_DELTA:
@@ -1013,14 +1014,15 @@ static void check_object(struct object_entry *entry)
                        case OBJ_OFS_DELTA:
                                buf = use_pack(p, &w_curs,
                                        entry->in_pack_offset + used, NULL);
-                               c = buf[used++];
+                               used_0 = 0;
+                               c = buf[used_0++];
                                ofs = c & 127;
                                while (c & 128) {
                                        ofs += 1;
                                        if (!ofs || ofs & ~(~0UL >> 7))
                                                die("delta base offset overflow in pack for %s",
                                                    sha1_to_hex(entry->sha1));
-                                       c = buf[used++];
+                                       c = buf[used_0++];
                                        ofs = (ofs << 7) + (c & 127);
                                }
                                if (ofs >= entry->in_pack_offset)
@@ -1028,6 +1030,7 @@ static void check_object(struct object_entry *entry)
                                            sha1_to_hex(entry->sha1));
                                ofs = entry->in_pack_offset - ofs;
                                base_name = find_packed_object_name(p, ofs);
+                               used += used_0;
                                break;
                        default:
                                base_name = NULL;