| #include "builtin.h" |
| #include "cache.h" |
| #include "config.h" |
| #include "object.h" |
| #include "delta.h" |
| #include "pack.h" |
| #include "blob.h" |
| #include "commit.h" |
| #include "tag.h" |
| #include "tree.h" |
| #include "tree-walk.h" |
| #include "progress.h" |
| #include "decorate.h" |
| #include "fsck.h" |
| |
| static int dry_run, quiet, recover, has_errors, strict; |
| static const char unpack_usage[] = "git unpack-objects [-n] [-q] [-r] [--strict]"; |
| |
| /* We always read in 4kB chunks. */ |
| static unsigned char buffer[4096]; |
| static unsigned int offset, len; |
| static off_t consumed_bytes; |
| static off_t max_input_size; |
| static git_hash_ctx ctx; |
| static struct fsck_options fsck_options = FSCK_OPTIONS_STRICT; |
| |
| /* |
| * When running under --strict mode, objects whose reachability are |
| * suspect are kept in core without getting written in the object |
| * store. |
| */ |
| struct obj_buffer { |
| char *buffer; |
| unsigned long size; |
| }; |
| |
| static struct decoration obj_decorate; |
| |
| static struct obj_buffer *lookup_object_buffer(struct object *base) |
| { |
| return lookup_decoration(&obj_decorate, base); |
| } |
| |
| static void add_object_buffer(struct object *object, char *buffer, unsigned long size) |
| { |
| struct obj_buffer *obj; |
| obj = xcalloc(1, sizeof(struct obj_buffer)); |
| obj->buffer = buffer; |
| obj->size = size; |
| if (add_decoration(&obj_decorate, object, obj)) |
| die("object %s tried to add buffer twice!", oid_to_hex(&object->oid)); |
| } |
| |
| /* |
| * Make sure at least "min" bytes are available in the buffer, and |
| * return the pointer to the buffer. |
| */ |
| static void *fill(int min) |
| { |
| if (min <= len) |
| return buffer + offset; |
| if (min > sizeof(buffer)) |
| die("cannot fill %d bytes", min); |
| if (offset) { |
| the_hash_algo->update_fn(&ctx, buffer, offset); |
| memmove(buffer, buffer + offset, len); |
| offset = 0; |
| } |
| do { |
| ssize_t ret = xread(0, buffer + len, sizeof(buffer) - len); |
| if (ret <= 0) { |
| if (!ret) |
| die("early EOF"); |
| die_errno("read error on input"); |
| } |
| len += ret; |
| } while (len < min); |
| return buffer; |
| } |
| |
| static void use(int bytes) |
| { |
| if (bytes > len) |
| die("used more bytes than were available"); |
| len -= bytes; |
| offset += bytes; |
| |
| /* make sure off_t is sufficiently large not to wrap */ |
| if (signed_add_overflows(consumed_bytes, bytes)) |
| die("pack too large for current definition of off_t"); |
| consumed_bytes += bytes; |
| if (max_input_size && consumed_bytes > max_input_size) |
| die(_("pack exceeds maximum allowed size")); |
| } |
| |
| static void *get_data(unsigned long size) |
| { |
| git_zstream stream; |
| void *buf = xmallocz(size); |
| |
| memset(&stream, 0, sizeof(stream)); |
| |
| stream.next_out = buf; |
| stream.avail_out = size; |
| stream.next_in = fill(1); |
| stream.avail_in = len; |
| git_inflate_init(&stream); |
| |
| for (;;) { |
| int ret = git_inflate(&stream, 0); |
| use(len - stream.avail_in); |
| if (stream.total_out == size && ret == Z_STREAM_END) |
| break; |
| if (ret != Z_OK) { |
| error("inflate returned %d", ret); |
| FREE_AND_NULL(buf); |
| if (!recover) |
| exit(1); |
| has_errors = 1; |
| break; |
| } |
| stream.next_in = fill(1); |
| stream.avail_in = len; |
| } |
| git_inflate_end(&stream); |
| return buf; |
| } |
| |
| struct delta_info { |
| struct object_id base_oid; |
| unsigned nr; |
| off_t base_offset; |
| unsigned long size; |
| void *delta; |
| struct delta_info *next; |
| }; |
| |
| static struct delta_info *delta_list; |
| |
| static void add_delta_to_list(unsigned nr, const struct object_id *base_oid, |
| off_t base_offset, |
| void *delta, unsigned long size) |
| { |
| struct delta_info *info = xmalloc(sizeof(*info)); |
| |
| oidcpy(&info->base_oid, base_oid); |
| info->base_offset = base_offset; |
| info->size = size; |
| info->delta = delta; |
| info->nr = nr; |
| info->next = delta_list; |
| delta_list = info; |
| } |
| |
| struct obj_info { |
| off_t offset; |
| struct object_id oid; |
| struct object *obj; |
| }; |
| |
| /* Remember to update object flag allocation in object.h */ |
| #define FLAG_OPEN (1u<<20) |
| #define FLAG_WRITTEN (1u<<21) |
| |
| static struct obj_info *obj_list; |
| static unsigned nr_objects; |
| |
| /* |
| * Called only from check_object() after it verified this object |
| * is Ok. |
| */ |
| static void write_cached_object(struct object *obj, struct obj_buffer *obj_buf) |
| { |
| struct object_id oid; |
| |
| if (write_object_file(obj_buf->buffer, obj_buf->size, |
| type_name(obj->type), &oid) < 0) |
| die("failed to write object %s", oid_to_hex(&obj->oid)); |
| obj->flags |= FLAG_WRITTEN; |
| } |
| |
| /* |
| * At the very end of the processing, write_rest() scans the objects |
| * that have reachability requirements and calls this function. |
| * Verify its reachability and validity recursively and write it out. |
| */ |
| static int check_object(struct object *obj, int type, void *data, struct fsck_options *options) |
| { |
| struct obj_buffer *obj_buf; |
| |
| if (!obj) |
| return 1; |
| |
| if (obj->flags & FLAG_WRITTEN) |
| return 0; |
| |
| if (type != OBJ_ANY && obj->type != type) |
| die("object type mismatch"); |
| |
| if (!(obj->flags & FLAG_OPEN)) { |
| unsigned long size; |
| int type = sha1_object_info(obj->oid.hash, &size); |
| if (type != obj->type || type <= 0) |
| die("object of unexpected type"); |
| obj->flags |= FLAG_WRITTEN; |
| return 0; |
| } |
| |
| obj_buf = lookup_object_buffer(obj); |
| if (!obj_buf) |
| die("Whoops! Cannot find object '%s'", oid_to_hex(&obj->oid)); |
| if (fsck_object(obj, obj_buf->buffer, obj_buf->size, &fsck_options)) |
| die("Error in object"); |
| fsck_options.walk = check_object; |
| if (fsck_walk(obj, NULL, &fsck_options)) |
| die("Error on reachable objects of %s", oid_to_hex(&obj->oid)); |
| write_cached_object(obj, obj_buf); |
| return 0; |
| } |
| |
| static void write_rest(void) |
| { |
| unsigned i; |
| for (i = 0; i < nr_objects; i++) { |
| if (obj_list[i].obj) |
| check_object(obj_list[i].obj, OBJ_ANY, NULL, NULL); |
| } |
| } |
| |
| static void added_object(unsigned nr, enum object_type type, |
| void *data, unsigned long size); |
| |
| /* |
| * Write out nr-th object from the list, now we know the contents |
| * of it. Under --strict, this buffers structured objects in-core, |
| * to be checked at the end. |
| */ |
| static void write_object(unsigned nr, enum object_type type, |
| void *buf, unsigned long size) |
| { |
| if (!strict) { |
| if (write_object_file(buf, size, type_name(type), |
| &obj_list[nr].oid) < 0) |
| die("failed to write object"); |
| added_object(nr, type, buf, size); |
| free(buf); |
| obj_list[nr].obj = NULL; |
| } else if (type == OBJ_BLOB) { |
| struct blob *blob; |
| if (write_object_file(buf, size, type_name(type), |
| &obj_list[nr].oid) < 0) |
| die("failed to write object"); |
| added_object(nr, type, buf, size); |
| free(buf); |
| |
| blob = lookup_blob(&obj_list[nr].oid); |
| if (blob) |
| blob->object.flags |= FLAG_WRITTEN; |
| else |
| die("invalid blob object"); |
| obj_list[nr].obj = NULL; |
| } else { |
| struct object *obj; |
| int eaten; |
| hash_object_file(buf, size, type_name(type), &obj_list[nr].oid); |
| added_object(nr, type, buf, size); |
| obj = parse_object_buffer(&obj_list[nr].oid, type, size, buf, |
| &eaten); |
| if (!obj) |
| die("invalid %s", type_name(type)); |
| add_object_buffer(obj, buf, size); |
| obj->flags |= FLAG_OPEN; |
| obj_list[nr].obj = obj; |
| } |
| } |
| |
| static void resolve_delta(unsigned nr, enum object_type type, |
| void *base, unsigned long base_size, |
| void *delta, unsigned long delta_size) |
| { |
| void *result; |
| unsigned long result_size; |
| |
| result = patch_delta(base, base_size, |
| delta, delta_size, |
| &result_size); |
| if (!result) |
| die("failed to apply delta"); |
| free(delta); |
| write_object(nr, type, result, result_size); |
| } |
| |
| /* |
| * We now know the contents of an object (which is nr-th in the pack); |
| * resolve all the deltified objects that are based on it. |
| */ |
| static void added_object(unsigned nr, enum object_type type, |
| void *data, unsigned long size) |
| { |
| struct delta_info **p = &delta_list; |
| struct delta_info *info; |
| |
| while ((info = *p) != NULL) { |
| if (!oidcmp(&info->base_oid, &obj_list[nr].oid) || |
| info->base_offset == obj_list[nr].offset) { |
| *p = info->next; |
| p = &delta_list; |
| resolve_delta(info->nr, type, data, size, |
| info->delta, info->size); |
| free(info); |
| continue; |
| } |
| p = &info->next; |
| } |
| } |
| |
| static void unpack_non_delta_entry(enum object_type type, unsigned long size, |
| unsigned nr) |
| { |
| void *buf = get_data(size); |
| |
| if (!dry_run && buf) |
| write_object(nr, type, buf, size); |
| else |
| free(buf); |
| } |
| |
| static int resolve_against_held(unsigned nr, const struct object_id *base, |
| void *delta_data, unsigned long delta_size) |
| { |
| struct object *obj; |
| struct obj_buffer *obj_buffer; |
| obj = lookup_object(base->hash); |
| if (!obj) |
| return 0; |
| obj_buffer = lookup_object_buffer(obj); |
| if (!obj_buffer) |
| return 0; |
| resolve_delta(nr, obj->type, obj_buffer->buffer, |
| obj_buffer->size, delta_data, delta_size); |
| return 1; |
| } |
| |
| static void unpack_delta_entry(enum object_type type, unsigned long delta_size, |
| unsigned nr) |
| { |
| void *delta_data, *base; |
| unsigned long base_size; |
| struct object_id base_oid; |
| |
| if (type == OBJ_REF_DELTA) { |
| hashcpy(base_oid.hash, fill(the_hash_algo->rawsz)); |
| use(the_hash_algo->rawsz); |
| delta_data = get_data(delta_size); |
| if (dry_run || !delta_data) { |
| free(delta_data); |
| return; |
| } |
| if (has_object_file(&base_oid)) |
| ; /* Ok we have this one */ |
| else if (resolve_against_held(nr, &base_oid, |
| delta_data, delta_size)) |
| return; /* we are done */ |
| else { |
| /* cannot resolve yet --- queue it */ |
| oidclr(&obj_list[nr].oid); |
| add_delta_to_list(nr, &base_oid, 0, delta_data, delta_size); |
| return; |
| } |
| } else { |
| unsigned base_found = 0; |
| unsigned char *pack, c; |
| off_t base_offset; |
| unsigned lo, mid, hi; |
| |
| pack = fill(1); |
| c = *pack; |
| use(1); |
| base_offset = c & 127; |
| while (c & 128) { |
| base_offset += 1; |
| if (!base_offset || MSB(base_offset, 7)) |
| die("offset value overflow for delta base object"); |
| pack = fill(1); |
| c = *pack; |
| use(1); |
| base_offset = (base_offset << 7) + (c & 127); |
| } |
| base_offset = obj_list[nr].offset - base_offset; |
| if (base_offset <= 0 || base_offset >= obj_list[nr].offset) |
| die("offset value out of bound for delta base object"); |
| |
| delta_data = get_data(delta_size); |
| if (dry_run || !delta_data) { |
| free(delta_data); |
| return; |
| } |
| lo = 0; |
| hi = nr; |
| while (lo < hi) { |
| mid = lo + (hi - lo) / 2; |
| if (base_offset < obj_list[mid].offset) { |
| hi = mid; |
| } else if (base_offset > obj_list[mid].offset) { |
| lo = mid + 1; |
| } else { |
| oidcpy(&base_oid, &obj_list[mid].oid); |
| base_found = !is_null_oid(&base_oid); |
| break; |
| } |
| } |
| if (!base_found) { |
| /* |
| * The delta base object is itself a delta that |
| * has not been resolved yet. |
| */ |
| oidclr(&obj_list[nr].oid); |
| add_delta_to_list(nr, &null_oid, base_offset, delta_data, delta_size); |
| return; |
| } |
| } |
| |
| if (resolve_against_held(nr, &base_oid, delta_data, delta_size)) |
| return; |
| |
| base = read_sha1_file(base_oid.hash, &type, &base_size); |
| if (!base) { |
| error("failed to read delta-pack base object %s", |
| oid_to_hex(&base_oid)); |
| if (!recover) |
| exit(1); |
| has_errors = 1; |
| return; |
| } |
| resolve_delta(nr, type, base, base_size, delta_data, delta_size); |
| free(base); |
| } |
| |
| static void unpack_one(unsigned nr) |
| { |
| unsigned shift; |
| unsigned char *pack; |
| unsigned long size, c; |
| enum object_type type; |
| |
| obj_list[nr].offset = consumed_bytes; |
| |
| pack = fill(1); |
| c = *pack; |
| use(1); |
| type = (c >> 4) & 7; |
| size = (c & 15); |
| shift = 4; |
| while (c & 0x80) { |
| pack = fill(1); |
| c = *pack; |
| use(1); |
| size += (c & 0x7f) << shift; |
| shift += 7; |
| } |
| |
| switch (type) { |
| case OBJ_COMMIT: |
| case OBJ_TREE: |
| case OBJ_BLOB: |
| case OBJ_TAG: |
| unpack_non_delta_entry(type, size, nr); |
| return; |
| case OBJ_REF_DELTA: |
| case OBJ_OFS_DELTA: |
| unpack_delta_entry(type, size, nr); |
| return; |
| default: |
| error("bad object type %d", type); |
| has_errors = 1; |
| if (recover) |
| return; |
| exit(1); |
| } |
| } |
| |
| static void unpack_all(void) |
| { |
| int i; |
| struct progress *progress = NULL; |
| struct pack_header *hdr = fill(sizeof(struct pack_header)); |
| |
| nr_objects = ntohl(hdr->hdr_entries); |
| |
| if (ntohl(hdr->hdr_signature) != PACK_SIGNATURE) |
| die("bad pack file"); |
| if (!pack_version_ok(hdr->hdr_version)) |
| die("unknown pack file version %"PRIu32, |
| ntohl(hdr->hdr_version)); |
| use(sizeof(struct pack_header)); |
| |
| if (!quiet) |
| progress = start_progress(_("Unpacking objects"), nr_objects); |
| obj_list = xcalloc(nr_objects, sizeof(*obj_list)); |
| for (i = 0; i < nr_objects; i++) { |
| unpack_one(i); |
| display_progress(progress, i + 1); |
| } |
| stop_progress(&progress); |
| |
| if (delta_list) |
| die("unresolved deltas left after unpacking"); |
| } |
| |
| int cmd_unpack_objects(int argc, const char **argv, const char *prefix) |
| { |
| int i; |
| struct object_id oid; |
| |
| check_replace_refs = 0; |
| |
| git_config(git_default_config, NULL); |
| |
| quiet = !isatty(2); |
| |
| for (i = 1 ; i < argc; i++) { |
| const char *arg = argv[i]; |
| |
| if (*arg == '-') { |
| if (!strcmp(arg, "-n")) { |
| dry_run = 1; |
| continue; |
| } |
| if (!strcmp(arg, "-q")) { |
| quiet = 1; |
| continue; |
| } |
| if (!strcmp(arg, "-r")) { |
| recover = 1; |
| continue; |
| } |
| if (!strcmp(arg, "--strict")) { |
| strict = 1; |
| continue; |
| } |
| if (skip_prefix(arg, "--strict=", &arg)) { |
| strict = 1; |
| fsck_set_msg_types(&fsck_options, arg); |
| continue; |
| } |
| if (starts_with(arg, "--pack_header=")) { |
| struct pack_header *hdr; |
| char *c; |
| |
| hdr = (struct pack_header *)buffer; |
| hdr->hdr_signature = htonl(PACK_SIGNATURE); |
| hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10)); |
| if (*c != ',') |
| die("bad %s", arg); |
| hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10)); |
| if (*c) |
| die("bad %s", arg); |
| len = sizeof(*hdr); |
| continue; |
| } |
| if (skip_prefix(arg, "--max-input-size=", &arg)) { |
| max_input_size = strtoumax(arg, NULL, 10); |
| continue; |
| } |
| usage(unpack_usage); |
| } |
| |
| /* We don't take any non-flag arguments now.. Maybe some day */ |
| usage(unpack_usage); |
| } |
| the_hash_algo->init_fn(&ctx); |
| unpack_all(); |
| the_hash_algo->update_fn(&ctx, buffer, offset); |
| the_hash_algo->final_fn(oid.hash, &ctx); |
| if (strict) |
| write_rest(); |
| if (hashcmp(fill(the_hash_algo->rawsz), oid.hash)) |
| die("final sha1 did not match"); |
| use(the_hash_algo->rawsz); |
| |
| /* Write the last part of the buffer to stdout */ |
| while (len) { |
| int ret = xwrite(1, buffer + offset, len); |
| if (ret <= 0) |
| break; |
| len -= ret; |
| offset += ret; |
| } |
| |
| /* All done */ |
| return has_errors; |
| } |