diff options
Diffstat (limited to 'sha1_file.c')
-rw-r--r-- | sha1_file.c | 219 |
1 files changed, 140 insertions, 79 deletions
diff --git a/sha1_file.c b/sha1_file.c index 523417027a..32244d704e 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -13,6 +13,7 @@ #include "commit.h" #include "tag.h" #include "tree.h" +#include "refs.h" #ifndef O_NOATIME #if defined(__linux__) && (defined(__i386__) || defined(__PPC__)) @@ -437,7 +438,7 @@ static int check_packed_git_idx(const char *path, struct packed_git *p) void *idx_map; struct pack_idx_header *hdr; size_t idx_size; - uint32_t nr, i, *index; + uint32_t version, nr, i, *index; int fd = open(path, O_RDONLY); struct stat st; @@ -455,21 +456,23 @@ static int check_packed_git_idx(const char *path, struct packed_git *p) idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0); close(fd); - /* a future index format would start with this, as older git - * binaries would fail the non-monotonic index check below. - * give a nicer warning to the user if we can. - */ hdr = idx_map; if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) { - munmap(idx_map, idx_size); - return error("index file %s is a newer version" - " and is not supported by this binary" - " (try upgrading GIT to a newer version)", - path); - } + version = ntohl(hdr->idx_version); + if (version < 2 || version > 2) { + munmap(idx_map, idx_size); + return error("index file %s is version %d" + " and is not supported by this binary" + " (try upgrading GIT to a newer version)", + path, version); + } + } else + version = 1; nr = 0; index = idx_map; + if (version > 1) + index += 2; /* skip index header */ for (i = 0; i < 256; i++) { uint32_t n = ntohl(index[i]); if (n < nr) { @@ -479,21 +482,51 @@ static int check_packed_git_idx(const char *path, struct packed_git *p) nr = n; } - /* - * Total size: - * - 256 index entries 4 bytes each - * - 24-byte entries * nr (20-byte sha1 + 4-byte offset) - * - 20-byte SHA1 of the packfile - * - 20-byte SHA1 file checksum - */ - if (idx_size != 4*256 + nr * 24 + 20 + 20) { - munmap(idx_map, idx_size); - return error("wrong index file size in %s", path); + if (version == 1) { + /* + * Total size: + * - 256 index entries 4 bytes each + * - 24-byte entries * nr (20-byte sha1 + 4-byte offset) + * - 20-byte SHA1 of the packfile + * - 20-byte SHA1 file checksum + */ + if (idx_size != 4*256 + nr * 24 + 20 + 20) { + munmap(idx_map, idx_size); + return error("wrong index file size in %s", path); + } + } else if (version == 2) { + /* + * Minimum size: + * - 8 bytes of header + * - 256 index entries 4 bytes each + * - 20-byte sha1 entry * nr + * - 4-byte crc entry * nr + * - 4-byte offset entry * nr + * - 20-byte SHA1 of the packfile + * - 20-byte SHA1 file checksum + * And after the 4-byte offset table might be a + * variable sized table containing 8-byte entries + * for offsets larger than 2^31. + */ + unsigned long min_size = 8 + 4*256 + nr*(20 + 4 + 4) + 20 + 20; + if (idx_size < min_size || idx_size > min_size + (nr - 1)*8) { + munmap(idx_map, idx_size); + return error("wrong index file size in %s", path); + } + if (idx_size != min_size) { + /* make sure we can deal with large pack offsets */ + off_t x = 0x7fffffffUL, y = 0xffffffffUL; + if (x > (x + 1) || y > (y + 1)) { + munmap(idx_map, idx_size); + return error("pack too large for current definition of off_t in %s", path); + } + } } - p->index_version = 1; + p->index_version = version; p->index_data = idx_map; p->index_size = idx_size; + p->num_objects = nr; return 0; } @@ -605,11 +638,11 @@ static int open_packed_git_1(struct packed_git *p) p->pack_name, ntohl(hdr.hdr_version)); /* Verify the pack matches its index. */ - if (num_packed_objects(p) != ntohl(hdr.hdr_entries)) + if (p->num_objects != ntohl(hdr.hdr_entries)) return error("packfile %s claims to have %u objects" - " while index size indicates %u objects", - p->pack_name, ntohl(hdr.hdr_entries), - num_packed_objects(p)); + " while index indicates %u objects", + p->pack_name, ntohl(hdr.hdr_entries), + p->num_objects); if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1) return error("end of packfile %s is unavailable", p->pack_name); if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1)) @@ -1128,6 +1161,43 @@ static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type return unpack_sha1_rest(&stream, hdr, *size, sha1); } +unsigned long get_size_from_delta(struct packed_git *p, + struct pack_window **w_curs, + off_t curpos) +{ + const unsigned char *data; + unsigned char delta_head[20], *in; + z_stream stream; + int st; + + memset(&stream, 0, sizeof(stream)); + stream.next_out = delta_head; + stream.avail_out = sizeof(delta_head); + + inflateInit(&stream); + do { + in = use_pack(p, w_curs, curpos, &stream.avail_in); + stream.next_in = in; + st = inflate(&stream, Z_FINISH); + curpos += stream.next_in - in; + } while ((st == Z_OK || st == Z_BUF_ERROR) && + stream.total_out < sizeof(delta_head)); + inflateEnd(&stream); + if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head)) + die("delta data unpack-initial failed"); + + /* Examine the initial part of the delta to figure out + * the result size. + */ + data = delta_head; + + /* ignore base size */ + get_delta_hdr_size(&data, delta_head+sizeof(delta_head)); + + /* Read the result size */ + return get_delta_hdr_size(&data, delta_head+sizeof(delta_head)); +} + static off_t get_delta_base(struct packed_git *p, struct pack_window **w_curs, off_t *curpos, @@ -1149,7 +1219,7 @@ static off_t get_delta_base(struct packed_git *p, base_offset = c & 127; while (c & 128) { base_offset += 1; - if (!base_offset || base_offset & ~(~0UL >> 7)) + if (!base_offset || MSB(base_offset, 7)) die("offset value overflow for delta base object"); c = base_info[used++]; base_offset = (base_offset << 7) + (c & 127); @@ -1191,40 +1261,8 @@ static int packed_delta_info(struct packed_git *p, * based on a base with a wrong size. This saves tons of * inflate() calls. */ - if (sizep) { - const unsigned char *data; - unsigned char delta_head[20], *in; - z_stream stream; - int st; - - memset(&stream, 0, sizeof(stream)); - stream.next_out = delta_head; - stream.avail_out = sizeof(delta_head); - - inflateInit(&stream); - do { - in = use_pack(p, w_curs, curpos, &stream.avail_in); - stream.next_in = in; - st = inflate(&stream, Z_FINISH); - curpos += stream.next_in - in; - } while ((st == Z_OK || st == Z_BUF_ERROR) - && stream.total_out < sizeof(delta_head)); - inflateEnd(&stream); - if ((st != Z_STREAM_END) && - stream.total_out != sizeof(delta_head)) - die("delta data unpack-initial failed"); - - /* Examine the initial part of the delta to figure out - * the result size. - */ - data = delta_head; - - /* ignore base size */ - get_delta_hdr_size(&data, delta_head+sizeof(delta_head)); - - /* Read the result size */ - *sizep = get_delta_hdr_size(&data, delta_head+sizeof(delta_head)); - } + if (sizep) + *sizep = get_size_from_delta(p, w_curs, curpos); return type; } @@ -1526,38 +1564,60 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset, return data; } -uint32_t num_packed_objects(const struct packed_git *p) +const unsigned char *nth_packed_object_sha1(const struct packed_git *p, + uint32_t n) { - /* See check_packed_git_idx() */ - return (uint32_t)((p->index_size - 20 - 20 - 4*256) / 24); + const unsigned char *index = p->index_data; + if (n >= p->num_objects) + return NULL; + index += 4 * 256; + if (p->index_version == 1) { + return index + 24 * n + 4; + } else { + index += 8; + return index + 20 * n; + } } -int nth_packed_object_sha1(const struct packed_git *p, uint32_t n, - unsigned char* sha1) +static off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n) { const unsigned char *index = p->index_data; index += 4 * 256; - if (num_packed_objects(p) <= n) - return -1; - hashcpy(sha1, index + 24 * n + 4); - return 0; + if (p->index_version == 1) { + return ntohl(*((uint32_t *)(index + 24 * n))); + } else { + uint32_t off; + index += 8 + p->num_objects * (20 + 4); + off = ntohl(*((uint32_t *)(index + 4 * n))); + if (!(off & 0x80000000)) + return off; + index += p->num_objects * 4 + (off & 0x7fffffff) * 8; + return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) | + ntohl(*((uint32_t *)(index + 4))); + } } off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *p) { const uint32_t *level1_ofs = p->index_data; - int hi = ntohl(level1_ofs[*sha1]); - int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1])); const unsigned char *index = p->index_data; + unsigned hi, lo; + if (p->index_version > 1) { + level1_ofs += 2; + index += 8; + } index += 4 * 256; + hi = ntohl(level1_ofs[*sha1]); + lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1])); do { - int mi = (lo + hi) / 2; - int cmp = hashcmp(index + 24 * mi + 4, sha1); + unsigned mi = (lo + hi) / 2; + unsigned x = (p->index_version > 1) ? (mi * 20) : (mi * 24 + 4); + int cmp = hashcmp(index + x, sha1); if (!cmp) - return ntohl(*((uint32_t *)((char *)index + (24 * mi)))); + return nth_packed_object_offset(p, mi); if (cmp > 0) hi = mi; else @@ -2278,10 +2338,9 @@ int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, */ if ((type == OBJ_BLOB) && S_ISREG(st->st_mode)) { unsigned long nsize = size; - char *nbuf = buf; - if (convert_to_git(path, &nbuf, &nsize)) { - if (size) - munmap(buf, size); + char *nbuf = convert_to_git(path, buf, &nsize); + if (nbuf) { + munmap(buf, size); size = nsize; buf = nbuf; re_allocated = 1; @@ -2333,6 +2392,8 @@ int index_path(unsigned char *sha1, const char *path, struct stat *st, int write path); free(target); break; + case S_IFDIR: + return resolve_gitlink_ref(path, "HEAD", sha1); default: return error("%s: unsupported file type", path); } |