diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/odb.c | 174 |
1 files changed, 155 insertions, 19 deletions
@@ -29,6 +29,7 @@ #include "fileops.h" #include "hash.h" #include "odb.h" +#include "delta-apply.h" #define GIT_PACK_NAME_MAX (5 + 40 + 1) @@ -74,6 +75,9 @@ struct git_pack { /** File descriptor for the .pack file. */ git_file pack_fd; + /** Memory map of the pack's contents */ + git_map pack_map; + /** The size of the .pack file. */ off_t pack_size; @@ -437,7 +441,7 @@ static int inflate_buffer(void *in, size_t inlen, void *out, size_t outlen) inflateEnd(&zs); - if ((status != Z_STREAM_END) || (zs.avail_in != 0)) + if ((status != Z_STREAM_END) /*|| (zs.avail_in != 0) */) return GIT_ERROR; if (zs.total_out != outlen) @@ -1160,23 +1164,26 @@ static int open_pack(git_pack *p) if (pack_openidx(p)) return GIT_ERROR; - if ((p->pack_fd = gitfo_open(pb, O_RDONLY)) < 0) { - p->pack_fd = -1; - pack_decidx(p); - return GIT_ERROR; - } + if ((p->pack_fd = gitfo_open(pb, O_RDONLY)) < 0) + goto error_cleanup; if (gitfo_fstat(p->pack_fd, &sb) || !S_ISREG(sb.st_mode) || p->pack_size != sb.st_size - || check_pack_hdr(p) || check_pack_sha1(p)) { - gitfo_close(p->pack_fd); - p->pack_fd = -1; - pack_decidx(p); - return GIT_ERROR; - } + || check_pack_hdr(p) || check_pack_sha1(p)) + goto error_cleanup; + + if (!git__is_sizet(p->pack_size) || + gitfo_map_ro(&p->pack_map, p->pack_fd, 0, (size_t)p->pack_size) < 0) + goto error_cleanup; pack_decidx(p); return GIT_SUCCESS; + +error_cleanup: + gitfo_close(p->pack_fd); + p->pack_fd = -1; + pack_decidx(p); + return GIT_ERROR; } static void pack_dec(git_pack *p) @@ -1194,8 +1201,10 @@ static void pack_dec(git_pack *p) free(p->im_fanout); free(p->im_off_idx); free(p->im_off_next); - if (p->pack_fd != -1) + if (p->pack_fd != -1) { gitfo_close(p->pack_fd); + gitfo_free_map(&p->pack_map); + } } gitlck_free(&p->lock); @@ -1475,14 +1484,141 @@ int git_odb__read_loose(git_obj *out, git_odb *db, const git_oid *id) return GIT_SUCCESS; } +static int unpack_object(git_obj *out, git_pack *p, index_entry *e); + +static int unpack_object_delta(git_obj *out, git_pack *p, + index_entry *base_entry, + uint8_t *delta_buffer, + size_t delta_deflated_size, + size_t delta_inflated_size) +{ + int res = 0; + uint8_t *delta = NULL; + git_obj base_obj; + + base_obj.data = NULL; + base_obj.type = GIT_OBJ_BAD; + base_obj.len = 0; + + if ((res = unpack_object(&base_obj, p, base_entry)) < 0) + goto cleanup; + + delta = git__malloc(delta_inflated_size + 1); + + if ((res = inflate_buffer(delta_buffer, delta_deflated_size, + delta, delta_inflated_size)) < 0) + goto cleanup; + + res = git__delta_apply(out, base_obj.data, base_obj.len, delta, delta_inflated_size); + + out->type = base_obj.type; + +cleanup: + free(delta); + git_obj_close(&base_obj); + return res; +} + static int unpack_object(git_obj *out, git_pack *p, index_entry *e) { - assert(out && p && e); + git_otype object_type; + size_t inflated_size, deflated_size, shift; + uint8_t *buffer, byte; + + assert(out && p && e && git__is_sizet(e->size)); if (open_pack(p)) return GIT_ERROR; - /* TODO - actually unpack the data! */ + buffer = (uint8_t *)p->pack_map.data + e->offset; + deflated_size = (size_t)e->size; + + if (deflated_size == 0) + deflated_size = p->pack_size - e->offset; + + byte = *buffer++ & 0xFF; + deflated_size--; + object_type = (byte >> 4) & 0x7; + inflated_size = byte & 0xF; + shift = 4; + + while (byte & 0x80) { + byte = *buffer++ & 0xFF; + deflated_size--; + inflated_size += (byte & 0x7F) << shift; + shift += 7; + } + + switch (object_type) { + case GIT_OBJ_COMMIT: + case GIT_OBJ_TREE: + case GIT_OBJ_BLOB: + case GIT_OBJ_TAG: { + + /* Handle a normal zlib stream */ + out->len = inflated_size; + out->type = object_type; + out->data = git__malloc(inflated_size + 1); + + if (inflate_buffer(buffer, deflated_size, out->data, out->len) < 0) { + free(out->data); + out->data = NULL; + return GIT_ERROR; + } + + return GIT_SUCCESS; + } + + case GIT_OBJ_OFS_DELTA: { + + off_t delta_offset; + index_entry entry; + + byte = *buffer++ & 0xFF; + delta_offset = byte & 0x7F; + + while (byte & 0x80) { + delta_offset += 1; + byte = *buffer++ & 0xFF; + delta_offset <<= 7; + delta_offset += (byte & 0x7F); + } + + entry.n = 0; + entry.oid = NULL; + entry.offset = e->offset - delta_offset; + entry.size = 0; + + if (unpack_object_delta(out, p, &entry, + buffer, deflated_size, inflated_size) < 0) + return GIT_ERROR; + + return GIT_SUCCESS; + } + + case GIT_OBJ_REF_DELTA: { + + git_oid base_id; + uint32_t n; + index_entry entry; + int res = GIT_ERROR; + + git_oid_mkraw(&base_id, buffer); + + if (!p->idx_search(&n, p, &base_id) && + !p->idx_get(&entry, p, n)) { + + /* FIXME: deflated_size - 20 ? */ + res = unpack_object_delta(out, p, &entry, + buffer + GIT_OID_RAWSZ, deflated_size, inflated_size); + } + + return res; + } + + default: + return GIT_EOBJCORRUPTED; + } return GIT_SUCCESS; } @@ -1497,15 +1633,15 @@ static int read_packed(git_obj *out, git_pack *p, const git_oid *id) if (pack_openidx(p)) return GIT_ERROR; + res = p->idx_search(&n, p, id); if (!res) res = p->idx_get(&e, p, n); - pack_decidx(p); - if (!res) { - /* TODO unpack object */ + if (!res) res = unpack_object(out, p, &e); - } + + pack_decidx(p); return res; } |