diff options
| -rw-r--r-- | sha1_file.c | 135 |
1 files changed, 84 insertions, 51 deletions
diff --git a/sha1_file.c b/sha1_file.c index 40b23297b2..71877a75fd 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -1560,50 +1560,6 @@ static off_t get_delta_base(struct packed_git *p, return base_offset; } -/* forward declaration for a mutually recursive function */ -static int packed_object_info(struct packed_git *p, off_t offset, - unsigned long *sizep, int *rtype); - -static int packed_delta_info(struct packed_git *p, - struct pack_window **w_curs, - off_t curpos, - enum object_type type, - off_t obj_offset, - unsigned long *sizep) -{ - off_t base_offset; - - base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset); - if (!base_offset) - return OBJ_BAD; - type = packed_object_info(p, base_offset, NULL, NULL); - if (type <= OBJ_NONE) { - 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) - return OBJ_BAD; - } - - /* We choose to only get the type of the base object and - * ignore potentially corrupt pack file that expects the delta - * based on a base with a wrong size. This saves tons of - * inflate() calls. - */ - if (sizep) { - *sizep = get_size_from_delta(p, w_curs, curpos); - if (*sizep == 0) - type = OBJ_BAD; - } - - return type; -} - int unpack_object_header(struct packed_git *p, struct pack_window **w_curs, off_t *curpos, @@ -1630,6 +1586,25 @@ int unpack_object_header(struct packed_git *p, return type; } +static int retry_bad_packed_offset(struct packed_git *p, off_t obj_offset) +{ + int type; + struct revindex_entry *revidx; + const unsigned char *sha1; + revidx = find_pack_revindex(p, obj_offset); + if (!revidx) + return OBJ_BAD; + sha1 = nth_packed_object_sha1(p, revidx->nr); + mark_bad_packed_object(p, sha1); + type = sha1_object_info(sha1, NULL); + if (type <= OBJ_NONE) + return OBJ_BAD; + return type; +} + + +#define POI_STACK_PREALLOC 64 + static int packed_object_info(struct packed_git *p, off_t obj_offset, unsigned long *sizep, int *rtype) { @@ -1637,31 +1612,89 @@ static int packed_object_info(struct packed_git *p, off_t obj_offset, unsigned long size; off_t curpos = obj_offset; enum object_type type; + off_t small_poi_stack[POI_STACK_PREALLOC]; + off_t *poi_stack = small_poi_stack; + int poi_stack_nr = 0, poi_stack_alloc = POI_STACK_PREALLOC; type = unpack_object_header(p, &w_curs, &curpos, &size); + if (rtype) *rtype = type; /* representation type */ + if (sizep) { + if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) { + off_t tmp_pos = curpos; + off_t base_offset = get_delta_base(p, &w_curs, &tmp_pos, + type, obj_offset); + if (!base_offset) { + type = OBJ_BAD; + goto out; + } + *sizep = get_size_from_delta(p, &w_curs, tmp_pos); + if (*sizep == 0) { + type = OBJ_BAD; + goto out; + } + } else { + *sizep = size; + } + } + + while (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) { + off_t base_offset; + /* Push the object we're going to leave behind */ + if (poi_stack_nr >= poi_stack_alloc && poi_stack == small_poi_stack) { + poi_stack_alloc = alloc_nr(poi_stack_nr); + poi_stack = xmalloc(sizeof(off_t)*poi_stack_alloc); + memcpy(poi_stack, small_poi_stack, sizeof(off_t)*poi_stack_nr); + } else { + ALLOC_GROW(poi_stack, poi_stack_nr+1, poi_stack_alloc); + } + poi_stack[poi_stack_nr++] = obj_offset; + /* If parsing the base offset fails, just unwind */ + base_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset); + if (!base_offset) + goto unwind; + curpos = obj_offset = base_offset; + type = unpack_object_header(p, &w_curs, &curpos, &size); + if (type <= OBJ_NONE) { + /* If getting the base itself fails, we first + * retry the base, otherwise unwind */ + type = retry_bad_packed_offset(p, base_offset); + if (type > OBJ_NONE) + goto out; + goto unwind; + } + } + switch (type) { - case OBJ_OFS_DELTA: - case OBJ_REF_DELTA: - type = packed_delta_info(p, &w_curs, curpos, - type, obj_offset, sizep); - break; + case OBJ_BAD: case OBJ_COMMIT: case OBJ_TREE: case OBJ_BLOB: case OBJ_TAG: - if (sizep) - *sizep = size; break; default: error("unknown object type %i at offset %"PRIuMAX" in %s", type, (uintmax_t)obj_offset, p->pack_name); type = OBJ_BAD; } + +out: + if (poi_stack != small_poi_stack) + free(poi_stack); unuse_pack(&w_curs); return type; + +unwind: + while (poi_stack_nr) { + obj_offset = poi_stack[--poi_stack_nr]; + type = retry_bad_packed_offset(p, obj_offset); + if (type > OBJ_NONE) + goto out; + } + type = OBJ_BAD; + goto out; } static void *unpack_compressed_entry(struct packed_git *p, |