diff options
Diffstat (limited to 'third_party/git/packfile.c')
| -rw-r--r-- | third_party/git/packfile.c | 2184 |
1 files changed, 0 insertions, 2184 deletions
diff --git a/third_party/git/packfile.c b/third_party/git/packfile.c deleted file mode 100644 index 0929ebe4fc74..000000000000 --- a/third_party/git/packfile.c +++ /dev/null @@ -1,2184 +0,0 @@ -#include "cache.h" -#include "list.h" -#include "pack.h" -#include "repository.h" -#include "dir.h" -#include "mergesort.h" -#include "packfile.h" -#include "delta.h" -#include "streaming.h" -#include "sha1-lookup.h" -#include "commit.h" -#include "object.h" -#include "tag.h" -#include "tree-walk.h" -#include "tree.h" -#include "object-store.h" -#include "midx.h" -#include "commit-graph.h" -#include "promisor-remote.h" - -char *odb_pack_name(struct strbuf *buf, - const unsigned char *hash, - const char *ext) -{ - strbuf_reset(buf); - strbuf_addf(buf, "%s/pack/pack-%s.%s", get_object_directory(), - hash_to_hex(hash), ext); - return buf->buf; -} - -char *sha1_pack_name(const unsigned char *sha1) -{ - static struct strbuf buf = STRBUF_INIT; - return odb_pack_name(&buf, sha1, "pack"); -} - -char *sha1_pack_index_name(const unsigned char *sha1) -{ - static struct strbuf buf = STRBUF_INIT; - return odb_pack_name(&buf, sha1, "idx"); -} - -static unsigned int pack_used_ctr; -static unsigned int pack_mmap_calls; -static unsigned int peak_pack_open_windows; -static unsigned int pack_open_windows; -static unsigned int pack_open_fds; -static unsigned int pack_max_fds; -static size_t peak_pack_mapped; -static size_t pack_mapped; - -#define SZ_FMT PRIuMAX -static inline uintmax_t sz_fmt(size_t s) { return s; } - -void pack_report(void) -{ - fprintf(stderr, - "pack_report: getpagesize() = %10" SZ_FMT "\n" - "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n" - "pack_report: core.packedGitLimit = %10" SZ_FMT "\n", - sz_fmt(getpagesize()), - sz_fmt(packed_git_window_size), - sz_fmt(packed_git_limit)); - fprintf(stderr, - "pack_report: pack_used_ctr = %10u\n" - "pack_report: pack_mmap_calls = %10u\n" - "pack_report: pack_open_windows = %10u / %10u\n" - "pack_report: pack_mapped = " - "%10" SZ_FMT " / %10" SZ_FMT "\n", - pack_used_ctr, - pack_mmap_calls, - pack_open_windows, peak_pack_open_windows, - sz_fmt(pack_mapped), sz_fmt(peak_pack_mapped)); -} - -/* - * Open and mmap the index file at path, perform a couple of - * consistency checks, then record its information to p. Return 0 on - * success. - */ -static int check_packed_git_idx(const char *path, struct packed_git *p) -{ - void *idx_map; - size_t idx_size; - int fd = git_open(path), ret; - struct stat st; - const unsigned int hashsz = the_hash_algo->rawsz; - - if (fd < 0) - return -1; - if (fstat(fd, &st)) { - close(fd); - return -1; - } - idx_size = xsize_t(st.st_size); - if (idx_size < 4 * 256 + hashsz + hashsz) { - close(fd); - return error("index file %s is too small", path); - } - idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0); - close(fd); - - ret = load_idx(path, hashsz, idx_map, idx_size, p); - - if (ret) - munmap(idx_map, idx_size); - - return ret; -} - -int load_idx(const char *path, const unsigned int hashsz, void *idx_map, - size_t idx_size, struct packed_git *p) -{ - struct pack_idx_header *hdr = idx_map; - uint32_t version, nr, i, *index; - - if (idx_size < 4 * 256 + hashsz + hashsz) - return error("index file %s is too small", path); - if (idx_map == NULL) - return error("empty data"); - - if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) { - version = ntohl(hdr->idx_version); - if (version < 2 || version > 2) - return error("index file %s is version %"PRIu32 - " 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) - return error("non-monotonic index %s", path); - nr = n; - } - - if (version == 1) { - /* - * Total size: - * - 256 index entries 4 bytes each - * - 24-byte entries * nr (object ID + 4-byte offset) - * - hash of the packfile - * - file checksum - */ - if (idx_size != 4 * 256 + nr * (hashsz + 4) + hashsz + hashsz) - return error("wrong index v1 file size in %s", path); - } else if (version == 2) { - /* - * Minimum size: - * - 8 bytes of header - * - 256 index entries 4 bytes each - * - object ID entry * nr - * - 4-byte crc entry * nr - * - 4-byte offset entry * nr - * - hash of the packfile - * - 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*(hashsz + 4 + 4) + hashsz + hashsz; - unsigned long max_size = min_size; - if (nr) - max_size += (nr - 1)*8; - if (idx_size < min_size || idx_size > max_size) - return error("wrong index v2 file size in %s", path); - if (idx_size != min_size && - /* - * make sure we can deal with large pack offsets. - * 31-bit signed offset won't be enough, neither - * 32-bit unsigned one will be. - */ - (sizeof(off_t) <= 4)) - return error("pack too large for current definition of off_t in %s", path); - p->crc_offset = 8 + 4 * 256 + nr * hashsz; - } - - p->index_version = version; - p->index_data = idx_map; - p->index_size = idx_size; - p->num_objects = nr; - return 0; -} - -int open_pack_index(struct packed_git *p) -{ - char *idx_name; - size_t len; - int ret; - - if (p->index_data) - return 0; - - if (!strip_suffix(p->pack_name, ".pack", &len)) - BUG("pack_name does not end in .pack"); - idx_name = xstrfmt("%.*s.idx", (int)len, p->pack_name); - ret = check_packed_git_idx(idx_name, p); - free(idx_name); - return ret; -} - -uint32_t get_pack_fanout(struct packed_git *p, uint32_t value) -{ - const uint32_t *level1_ofs = p->index_data; - - if (!level1_ofs) { - if (open_pack_index(p)) - return 0; - level1_ofs = p->index_data; - } - - if (p->index_version > 1) { - level1_ofs += 2; - } - - return ntohl(level1_ofs[value]); -} - -static struct packed_git *alloc_packed_git(int extra) -{ - struct packed_git *p = xmalloc(st_add(sizeof(*p), extra)); - memset(p, 0, sizeof(*p)); - p->pack_fd = -1; - return p; -} - -struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path) -{ - const char *path = sha1_pack_name(sha1); - size_t alloc = st_add(strlen(path), 1); - struct packed_git *p = alloc_packed_git(alloc); - - memcpy(p->pack_name, path, alloc); /* includes NUL */ - hashcpy(p->hash, sha1); - if (check_packed_git_idx(idx_path, p)) { - free(p); - return NULL; - } - - return p; -} - -static void scan_windows(struct packed_git *p, - struct packed_git **lru_p, - struct pack_window **lru_w, - struct pack_window **lru_l) -{ - struct pack_window *w, *w_l; - - for (w_l = NULL, w = p->windows; w; w = w->next) { - if (!w->inuse_cnt) { - if (!*lru_w || w->last_used < (*lru_w)->last_used) { - *lru_p = p; - *lru_w = w; - *lru_l = w_l; - } - } - w_l = w; - } -} - -static int unuse_one_window(struct packed_git *current) -{ - struct packed_git *p, *lru_p = NULL; - struct pack_window *lru_w = NULL, *lru_l = NULL; - - if (current) - scan_windows(current, &lru_p, &lru_w, &lru_l); - for (p = the_repository->objects->packed_git; p; p = p->next) - scan_windows(p, &lru_p, &lru_w, &lru_l); - if (lru_p) { - munmap(lru_w->base, lru_w->len); - pack_mapped -= lru_w->len; - if (lru_l) - lru_l->next = lru_w->next; - else - lru_p->windows = lru_w->next; - free(lru_w); - pack_open_windows--; - return 1; - } - return 0; -} - -void close_pack_windows(struct packed_git *p) -{ - while (p->windows) { - struct pack_window *w = p->windows; - - if (w->inuse_cnt) - die("pack '%s' still has open windows to it", - p->pack_name); - munmap(w->base, w->len); - pack_mapped -= w->len; - pack_open_windows--; - p->windows = w->next; - free(w); - } -} - -int close_pack_fd(struct packed_git *p) -{ - if (p->pack_fd < 0) - return 0; - - close(p->pack_fd); - pack_open_fds--; - p->pack_fd = -1; - - return 1; -} - -void close_pack_index(struct packed_git *p) -{ - if (p->index_data) { - munmap((void *)p->index_data, p->index_size); - p->index_data = NULL; - } -} - -void close_pack(struct packed_git *p) -{ - close_pack_windows(p); - close_pack_fd(p); - close_pack_index(p); -} - -void close_object_store(struct raw_object_store *o) -{ - struct packed_git *p; - - for (p = o->packed_git; p; p = p->next) - if (p->do_not_close) - BUG("want to close pack marked 'do-not-close'"); - else - close_pack(p); - - if (o->multi_pack_index) { - close_midx(o->multi_pack_index); - o->multi_pack_index = NULL; - } - - close_commit_graph(o); -} - -void unlink_pack_path(const char *pack_name, int force_delete) -{ - static const char *exts[] = {".pack", ".idx", ".keep", ".bitmap", ".promisor"}; - int i; - struct strbuf buf = STRBUF_INIT; - size_t plen; - - strbuf_addstr(&buf, pack_name); - strip_suffix_mem(buf.buf, &buf.len, ".pack"); - plen = buf.len; - - if (!force_delete) { - strbuf_addstr(&buf, ".keep"); - if (!access(buf.buf, F_OK)) { - strbuf_release(&buf); - return; - } - } - - for (i = 0; i < ARRAY_SIZE(exts); i++) { - strbuf_setlen(&buf, plen); - strbuf_addstr(&buf, exts[i]); - unlink(buf.buf); - } - - strbuf_release(&buf); -} - -/* - * The LRU pack is the one with the oldest MRU window, preferring packs - * with no used windows, or the oldest mtime if it has no windows allocated. - */ -static void find_lru_pack(struct packed_git *p, struct packed_git **lru_p, struct pack_window **mru_w, int *accept_windows_inuse) -{ - struct pack_window *w, *this_mru_w; - int has_windows_inuse = 0; - - /* - * Reject this pack if it has windows and the previously selected - * one does not. If this pack does not have windows, reject - * it if the pack file is newer than the previously selected one. - */ - if (*lru_p && !*mru_w && (p->windows || p->mtime > (*lru_p)->mtime)) - return; - - for (w = this_mru_w = p->windows; w; w = w->next) { - /* - * Reject this pack if any of its windows are in use, - * but the previously selected pack did not have any - * inuse windows. Otherwise, record that this pack - * has windows in use. - */ - if (w->inuse_cnt) { - if (*accept_windows_inuse) - has_windows_inuse = 1; - else - return; - } - - if (w->last_used > this_mru_w->last_used) - this_mru_w = w; - - /* - * Reject this pack if it has windows that have been - * used more recently than the previously selected pack. - * If the previously selected pack had windows inuse and - * we have not encountered a window in this pack that is - * inuse, skip this check since we prefer a pack with no - * inuse windows to one that has inuse windows. - */ - if (*mru_w && *accept_windows_inuse == has_windows_inuse && - this_mru_w->last_used > (*mru_w)->last_used) - return; - } - - /* - * Select this pack. - */ - *mru_w = this_mru_w; - *lru_p = p; - *accept_windows_inuse = has_windows_inuse; -} - -static int close_one_pack(void) -{ - struct packed_git *p, *lru_p = NULL; - struct pack_window *mru_w = NULL; - int accept_windows_inuse = 1; - - for (p = the_repository->objects->packed_git; p; p = p->next) { - if (p->pack_fd == -1) - continue; - find_lru_pack(p, &lru_p, &mru_w, &accept_windows_inuse); - } - - if (lru_p) - return close_pack_fd(lru_p); - - return 0; -} - -static unsigned int get_max_fd_limit(void) -{ -#ifdef RLIMIT_NOFILE - { - struct rlimit lim; - - if (!getrlimit(RLIMIT_NOFILE, &lim)) - return lim.rlim_cur; - } -#endif - -#ifdef _SC_OPEN_MAX - { - long open_max = sysconf(_SC_OPEN_MAX); - if (0 < open_max) - return open_max; - /* - * Otherwise, we got -1 for one of the two - * reasons: - * - * (1) sysconf() did not understand _SC_OPEN_MAX - * and signaled an error with -1; or - * (2) sysconf() said there is no limit. - * - * We _could_ clear errno before calling sysconf() to - * tell these two cases apart and return a huge number - * in the latter case to let the caller cap it to a - * value that is not so selfish, but letting the - * fallback OPEN_MAX codepath take care of these cases - * is a lot simpler. - */ - } -#endif - -#ifdef OPEN_MAX - return OPEN_MAX; -#else - return 1; /* see the caller ;-) */ -#endif -} - -const char *pack_basename(struct packed_git *p) -{ - const char *ret = strrchr(p->pack_name, '/'); - if (ret) - ret = ret + 1; /* skip past slash */ - else - ret = p->pack_name; /* we only have a base */ - return ret; -} - -/* - * Do not call this directly as this leaks p->pack_fd on error return; - * call open_packed_git() instead. - */ -static int open_packed_git_1(struct packed_git *p) -{ - struct stat st; - struct pack_header hdr; - unsigned char hash[GIT_MAX_RAWSZ]; - unsigned char *idx_hash; - ssize_t read_result; - const unsigned hashsz = the_hash_algo->rawsz; - - if (!p->index_data) { - struct multi_pack_index *m; - const char *pack_name = pack_basename(p); - - for (m = the_repository->objects->multi_pack_index; - m; m = m->next) { - if (midx_contains_pack(m, pack_name)) - break; - } - - if (!m && open_pack_index(p)) - return error("packfile %s index unavailable", p->pack_name); - } - - if (!pack_max_fds) { - unsigned int max_fds = get_max_fd_limit(); - - /* Save 3 for stdin/stdout/stderr, 22 for work */ - if (25 < max_fds) - pack_max_fds = max_fds - 25; - else - pack_max_fds = 1; - } - - while (pack_max_fds <= pack_open_fds && close_one_pack()) - ; /* nothing */ - - p->pack_fd = git_open(p->pack_name); - if (p->pack_fd < 0 || fstat(p->pack_fd, &st)) - return -1; - pack_open_fds++; - - /* If we created the struct before we had the pack we lack size. */ - if (!p->pack_size) { - if (!S_ISREG(st.st_mode)) - return error("packfile %s not a regular file", p->pack_name); - p->pack_size = st.st_size; - } else if (p->pack_size != st.st_size) - return error("packfile %s size changed", p->pack_name); - - /* Verify we recognize this pack file format. */ - read_result = read_in_full(p->pack_fd, &hdr, sizeof(hdr)); - if (read_result < 0) - return error_errno("error reading from %s", p->pack_name); - if (read_result != sizeof(hdr)) - return error("file %s is far too short to be a packfile", p->pack_name); - if (hdr.hdr_signature != htonl(PACK_SIGNATURE)) - return error("file %s is not a GIT packfile", p->pack_name); - if (!pack_version_ok(hdr.hdr_version)) - return error("packfile %s is version %"PRIu32" and not" - " supported (try upgrading GIT to a newer version)", - p->pack_name, ntohl(hdr.hdr_version)); - - /* Skip index checking if in multi-pack-index */ - if (!p->index_data) - return 0; - - /* Verify the pack matches its index. */ - if (p->num_objects != ntohl(hdr.hdr_entries)) - return error("packfile %s claims to have %"PRIu32" objects" - " while index indicates %"PRIu32" objects", - p->pack_name, ntohl(hdr.hdr_entries), - p->num_objects); - read_result = pread_in_full(p->pack_fd, hash, hashsz, - p->pack_size - hashsz); - if (read_result < 0) - return error_errno("error reading from %s", p->pack_name); - if (read_result != hashsz) - return error("packfile %s signature is unavailable", p->pack_name); - idx_hash = ((unsigned char *)p->index_data) + p->index_size - hashsz * 2; - if (!hasheq(hash, idx_hash)) - return error("packfile %s does not match index", p->pack_name); - return 0; -} - -static int open_packed_git(struct packed_git *p) -{ - if (!open_packed_git_1(p)) - return 0; - close_pack_fd(p); - return -1; -} - -static int in_window(struct pack_window *win, off_t offset) -{ - /* We must promise at least one full hash after the - * offset is available from this window, otherwise the offset - * is not actually in this window and a different window (which - * has that one hash excess) must be used. This is to support - * the object header and delta base parsing routines below. - */ - off_t win_off = win->offset; - return win_off <= offset - && (offset + the_hash_algo->rawsz) <= (win_off + win->len); -} - -unsigned char *use_pack(struct packed_git *p, - struct pack_window **w_cursor, - off_t offset, - unsigned long *left) -{ - struct pack_window *win = *w_cursor; - - /* Since packfiles end in a hash of their content and it's - * pointless to ask for an offset into the middle of that - * hash, and the in_window function above wouldn't match - * don't allow an offset too close to the end of the file. - */ - if (!p->pack_size && p->pack_fd == -1 && open_packed_git(p)) - die("packfile %s cannot be accessed", p->pack_name); - if (offset > (p->pack_size - the_hash_algo->rawsz)) - die("offset beyond end of packfile (truncated pack?)"); - if (offset < 0) - die(_("offset before end of packfile (broken .idx?)")); - - if (!win || !in_window(win, offset)) { - if (win) - win->inuse_cnt--; - for (win = p->windows; win; win = win->next) { - if (in_window(win, offset)) - break; - } - if (!win) { - size_t window_align = packed_git_window_size / 2; - off_t len; - - if (p->pack_fd == -1 && open_packed_git(p)) - die("packfile %s cannot be accessed", p->pack_name); - - win = xcalloc(1, sizeof(*win)); - win->offset = (offset / window_align) * window_align; - len = p->pack_size - win->offset; - if (len > packed_git_window_size) - len = packed_git_window_size; - win->len = (size_t)len; - pack_mapped += win->len; - while (packed_git_limit < pack_mapped - && unuse_one_window(p)) - ; /* nothing */ - win->base = xmmap_gently(NULL, win->len, - PROT_READ, MAP_PRIVATE, - p->pack_fd, win->offset); - if (win->base == MAP_FAILED) - die_errno("packfile %s cannot be mapped", - p->pack_name); - if (!win->offset && win->len == p->pack_size - && !p->do_not_close) - close_pack_fd(p); - pack_mmap_calls++; - pack_open_windows++; - if (pack_mapped > peak_pack_mapped) - peak_pack_mapped = pack_mapped; - if (pack_open_windows > peak_pack_open_windows) - peak_pack_open_windows = pack_open_windows; - win->next = p->windows; - p->windows = win; - } - } - if (win != *w_cursor) { - win->last_used = pack_used_ctr++; - win->inuse_cnt++; - *w_cursor = win; - } - offset -= win->offset; - if (left) - *left = win->len - xsize_t(offset); - return win->base + offset; -} - -void unuse_pack(struct pack_window **w_cursor) -{ - struct pack_window *w = *w_cursor; - if (w) { - w->inuse_cnt--; - *w_cursor = NULL; - } -} - -struct packed_git *add_packed_git(const char *path, size_t path_len, int local) -{ - struct stat st; - size_t alloc; - struct packed_git *p; - - /* - * Make sure a corresponding .pack file exists and that - * the index looks sane. - */ - if (!strip_suffix_mem(path, &path_len, ".idx")) - return NULL; - - /* - * ".promisor" is long enough to hold any suffix we're adding (and - * the use xsnprintf double-checks that) - */ - alloc = st_add3(path_len, strlen(".promisor"), 1); - p = alloc_packed_git(alloc); - memcpy(p->pack_name, path, path_len); - - xsnprintf(p->pack_name + path_len, alloc - path_len, ".keep"); - if (!access(p->pack_name, F_OK)) - p->pack_keep = 1; - - xsnprintf(p->pack_name + path_len, alloc - path_len, ".promisor"); - if (!access(p->pack_name, F_OK)) - p->pack_promisor = 1; - - xsnprintf(p->pack_name + path_len, alloc - path_len, ".pack"); - if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) { - free(p); - return NULL; - } - - /* ok, it looks sane as far as we can check without - * actually mapping the pack file. - */ - p->pack_size = st.st_size; - p->pack_local = local; - p->mtime = st.st_mtime; - if (path_len < the_hash_algo->hexsz || - get_sha1_hex(path + path_len - the_hash_algo->hexsz, p->hash)) - hashclr(p->hash); - return p; -} - -void install_packed_git(struct repository *r, struct packed_git *pack) -{ - if (pack->pack_fd != -1) - pack_open_fds++; - - pack->next = r->objects->packed_git; - r->objects->packed_git = pack; - - hashmap_entry_init(&pack->packmap_ent, strhash(pack->pack_name)); - hashmap_add(&r->objects->pack_map, &pack->packmap_ent); -} - -void (*report_garbage)(unsigned seen_bits, const char *path); - -static void report_helper(const struct string_list *list, - int seen_bits, int first, int last) -{ - if (seen_bits == (PACKDIR_FILE_PACK|PACKDIR_FILE_IDX)) - return; - - for (; first < last; first++) - report_garbage(seen_bits, list->items[first].string); -} - -static void report_pack_garbage(struct string_list *list) -{ - int i, baselen = -1, first = 0, seen_bits = 0; - - if (!report_garbage) - return; - - string_list_sort(list); - - for (i = 0; i < list->nr; i++) { - const char *path = list->items[i].string; - if (baselen != -1 && - strncmp(path, list->items[first].string, baselen)) { - report_helper(list, seen_bits, first, i); - baselen = -1; - seen_bits = 0; - } - if (baselen == -1) { - const char *dot = strrchr(path, '.'); - if (!dot) { - report_garbage(PACKDIR_FILE_GARBAGE, path); - continue; - } - baselen = dot - path + 1; - first = i; - } - if (!strcmp(path + baselen, "pack")) - seen_bits |= 1; - else if (!strcmp(path + baselen, "idx")) - seen_bits |= 2; - } - report_helper(list, seen_bits, first, list->nr); -} - -void for_each_file_in_pack_dir(const char *objdir, - each_file_in_pack_dir_fn fn, - void *data) -{ - struct strbuf path = STRBUF_INIT; - size_t dirnamelen; - DIR *dir; - struct dirent *de; - - strbuf_addstr(&path, objdir); - strbuf_addstr(&path, "/pack"); - dir = opendir(path.buf); - if (!dir) { - if (errno != ENOENT) - error_errno("unable to open object pack directory: %s", - path.buf); - strbuf_release(&path); - return; - } - strbuf_addch(&path, '/'); - dirnamelen = path.len; - while ((de = readdir(dir)) != NULL) { - if (is_dot_or_dotdot(de->d_name)) - continue; - - strbuf_setlen(&path, dirnamelen); - strbuf_addstr(&path, de->d_name); - - fn(path.buf, path.len, de->d_name, data); - } - - closedir(dir); - strbuf_release(&path); -} - -struct prepare_pack_data { - struct repository *r; - struct string_list *garbage; - int local; - struct multi_pack_index *m; -}; - -static void prepare_pack(const char *full_name, size_t full_name_len, - const char *file_name, void *_data) -{ - struct prepare_pack_data *data = (struct prepare_pack_data *)_data; - struct packed_git *p; - size_t base_len = full_name_len; - - if (strip_suffix_mem(full_name, &base_len, ".idx") && - !(data->m && midx_contains_pack(data->m, file_name))) { - struct hashmap_entry hent; - char *pack_name = xstrfmt("%.*s.pack", (int)base_len, full_name); - unsigned int hash = strhash(pack_name); - hashmap_entry_init(&hent, hash); - - /* Don't reopen a pack we already have. */ - if (!hashmap_get(&data->r->objects->pack_map, &hent, pack_name)) { - p = add_packed_git(full_name, full_name_len, data->local); - if (p) - install_packed_git(data->r, p); - } - free(pack_name); - } - - if (!report_garbage) - return; - - if (!strcmp(file_name, "multi-pack-index")) - return; - if (ends_with(file_name, ".idx") || - ends_with(file_name, ".pack") || - ends_with(file_name, ".bitmap") || - ends_with(file_name, ".keep") || - ends_with(file_name, ".promisor")) - string_list_append(data->garbage, full_name); - else - report_garbage(PACKDIR_FILE_GARBAGE, full_name); -} - -static void prepare_packed_git_one(struct repository *r, char *objdir, int local) -{ - struct prepare_pack_data data; - struct string_list garbage = STRING_LIST_INIT_DUP; - - data.m = r->objects->multi_pack_index; - - /* look for the multi-pack-index for this object directory */ - while (data.m && strcmp(data.m->object_dir, objdir)) - data.m = data.m->next; - - data.r = r; - data.garbage = &garbage; - data.local = local; - - for_each_file_in_pack_dir(objdir, prepare_pack, &data); - - report_pack_garbage(data.garbage); - string_list_clear(data.garbage, 0); -} - -static void prepare_packed_git(struct repository *r); -/* - * Give a fast, rough count of the number of objects in the repository. This - * ignores loose objects completely. If you have a lot of them, then either - * you should repack because your performance will be awful, or they are - * all unreachable objects about to be pruned, in which case they're not really - * interesting as a measure of repo size in the first place. - */ -unsigned long repo_approximate_object_count(struct repository *r) -{ - if (!r->objects->approximate_object_count_valid) { - unsigned long count; - struct multi_pack_index *m; - struct packed_git *p; - - prepare_packed_git(r); - count = 0; - for (m = get_multi_pack_index(r); m; m = m->next) - count += m->num_objects; - for (p = r->objects->packed_git; p; p = p->next) { - if (open_pack_index(p)) - continue; - count += p->num_objects; - } - r->objects->approximate_object_count = count; - r->objects->approximate_object_count_valid = 1; - } - return r->objects->approximate_object_count; -} - -static void *get_next_packed_git(const void *p) -{ - return ((const struct packed_git *)p)->next; -} - -static void set_next_packed_git(void *p, void *next) -{ - ((struct packed_git *)p)->next = next; -} - -static int sort_pack(const void *a_, const void *b_) -{ - const struct packed_git *a = a_; - const struct packed_git *b = b_; - int st; - - /* - * Local packs tend to contain objects specific to our - * variant of the project than remote ones. In addition, - * remote ones could be on a network mounted filesystem. - * Favor local ones for these reasons. - */ - st = a->pack_local - b->pack_local; - if (st) - return -st; - - /* - * Younger packs tend to contain more recent objects, - * and more recent objects tend to get accessed more - * often. - */ - if (a->mtime < b->mtime) - return 1; - else if (a->mtime == b->mtime) - return 0; - return -1; -} - -static void rearrange_packed_git(struct repository *r) -{ - r->objects->packed_git = llist_mergesort( - r->objects->packed_git, get_next_packed_git, - set_next_packed_git, sort_pack); -} - -static void prepare_packed_git_mru(struct repository *r) -{ - struct packed_git *p; - - INIT_LIST_HEAD(&r->objects->packed_git_mru); - - for (p = r->objects->packed_git; p; p = p->next) - list_add_tail(&p->mru, &r->objects->packed_git_mru); -} - -static void prepare_packed_git(struct repository *r) -{ - struct object_directory *odb; - - if (r->objects->packed_git_initialized) - return; - - prepare_alt_odb(r); - for (odb = r->objects->odb; odb; odb = odb->next) { - int local = (odb == r->objects->odb); - prepare_multi_pack_index_one(r, odb->path, local); - prepare_packed_git_one(r, odb->path, local); - } - rearrange_packed_git(r); - - prepare_packed_git_mru(r); - r->objects->packed_git_initialized = 1; -} - -void reprepare_packed_git(struct repository *r) -{ - struct object_directory *odb; - - obj_read_lock(); - for (odb = r->objects->odb; odb; odb = odb->next) - odb_clear_loose_cache(odb); - - r->objects->approximate_object_count_valid = 0; - r->objects->packed_git_initialized = 0; - prepare_packed_git(r); - obj_read_unlock(); -} - -struct packed_git *get_packed_git(struct repository *r) -{ - prepare_packed_git(r); - return r->objects->packed_git; -} - -struct multi_pack_index *get_multi_pack_index(struct repository *r) -{ - prepare_packed_git(r); - return r->objects->multi_pack_index; -} - -struct multi_pack_index *get_local_multi_pack_index(struct repository *r) -{ - struct multi_pack_index *m = get_multi_pack_index(r); - - /* no need to iterate; we always put the local one first (if any) */ - if (m && m->local) - return m; - - return NULL; -} - -struct packed_git *get_all_packs(struct repository *r) -{ - struct multi_pack_index *m; - - prepare_packed_git(r); - for (m = r->objects->multi_pack_index; m; m = m->next) { - uint32_t i; - for (i = 0; i < m->num_packs; i++) - prepare_midx_pack(r, m, i); - } - - return r->objects->packed_git; -} - -struct list_head *get_packed_git_mru(struct repository *r) -{ - prepare_packed_git(r); - return &r->objects->packed_git_mru; -} - -unsigned long unpack_object_header_buffer(const unsigned char *buf, - unsigned long len, enum object_type *type, unsigned long *sizep) -{ - unsigned shift; - unsigned long size, c; - unsigned long used = 0; - - c = buf[used++]; - *type = (c >> 4) & 7; - size = c & 15; - shift = 4; - while (c & 0x80) { - if (len <= used || bitsizeof(long) <= shift) { - error("bad object header"); - size = used = 0; - break; - } - c = buf[used++]; - size += (c & 0x7f) << shift; - shift += 7; - } - *sizep = size; - return used; -} - -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; - git_zstream stream; - int st; - - memset(&stream, 0, sizeof(stream)); - stream.next_out = delta_head; - stream.avail_out = sizeof(delta_head); - - git_inflate_init(&stream); - do { - in = use_pack(p, w_curs, curpos, &stream.avail_in); - stream.next_in = in; - /* - * Note: the window section returned by use_pack() must be - * available throughout git_inflate()'s unlocked execution. To - * ensure no other thread will modify the window in the - * meantime, we rely on the packed_window.inuse_cnt. This - * counter is incremented before window reading and checked - * before window disposal. - * - * Other worrying sections could be the call to close_pack_fd(), - * which can close packs even with in-use windows, and to - * reprepare_packed_git(). Regarding the former, mmap doc says: - * "closing the file descriptor does not unmap the region". And - * for the latter, it won't re-open already available packs. - */ - obj_read_unlock(); - st = git_inflate(&stream, Z_FINISH); - obj_read_lock(); - curpos += stream.next_in - in; - } while ((st == Z_OK || st == Z_BUF_ERROR) && - stream.total_out < sizeof(delta_head)); - git_inflate_end(&stream); - if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head)) { - error("delta data unpack-initial failed"); - return 0; - } - - /* 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)); -} - -int unpack_object_header(struct packed_git *p, - struct pack_window **w_curs, - off_t *curpos, - unsigned long *sizep) -{ - unsigned char *base; - unsigned long left; - unsigned long used; - enum object_type type; - - /* use_pack() assures us we have [base, base + 20) available - * as a range that we can look at. (Its actually the hash - * size that is assured.) With our object header encoding - * the maximum deflated object size is 2^137, which is just - * insane, so we know won't exceed what we have been given. - */ - base = use_pack(p, w_curs, *curpos, &left); - used = unpack_object_header_buffer(base, left, &type, sizep); - if (!used) { - type = OBJ_BAD; - } else - *curpos += used; - - return type; -} - -void mark_bad_packed_object(struct packed_git *p, const unsigned char *sha1) -{ - unsigned i; - const unsigned hashsz = the_hash_algo->rawsz; - for (i = 0; i < p->num_bad_objects; i++) - if (hasheq(sha1, p->bad_object_sha1 + hashsz * i)) - return; - p->bad_object_sha1 = xrealloc(p->bad_object_sha1, - st_mult(GIT_MAX_RAWSZ, - st_add(p->num_bad_objects, 1))); - hashcpy(p->bad_object_sha1 + hashsz * p->num_bad_objects, sha1); - p->num_bad_objects++; -} - -const struct packed_git *has_packed_and_bad(struct repository *r, - const unsigned char *sha1) -{ - struct packed_git *p; - unsigned i; - - for (p = r->objects->packed_git; p; p = p->next) - for (i = 0; i < p->num_bad_objects; i++) - if (hasheq(sha1, - p->bad_object_sha1 + the_hash_algo->rawsz * i)) - return p; - return NULL; -} - -off_t get_delta_base(struct packed_git *p, - struct pack_window **w_curs, - off_t *curpos, - enum object_type type, - off_t delta_obj_offset) -{ - unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL); - off_t base_offset; - - /* use_pack() assured us we have [base_info, base_info + 20) - * as a range that we can look at without walking off the - * end of the mapped window. Its actually the hash size - * that is assured. An OFS_DELTA longer than the hash size - * is stupid, as then a REF_DELTA would be smaller to store. - */ - if (type == OBJ_OFS_DELTA) { - unsigned used = 0; - unsigned char c = base_info[used++]; - base_offset = c & 127; - while (c & 128) { - base_offset += 1; - if (!base_offset || MSB(base_offset, 7)) - return 0; /* overflow */ - c = base_info[used++]; - base_offset = (base_offset << 7) + (c & 127); - } - base_offset = delta_obj_offset - base_offset; - if (base_offset <= 0 || base_offset >= delta_obj_offset) - return 0; /* out of bound */ - *curpos += used; - } else if (type == OBJ_REF_DELTA) { - /* The base entry _must_ be in the same pack */ - base_offset = find_pack_entry_one(base_info, p); - *curpos += the_hash_algo->rawsz; - } else - die("I am totally screwed"); - return base_offset; -} - -/* - * Like get_delta_base above, but we return the sha1 instead of the pack - * offset. This means it is cheaper for REF deltas (we do not have to do - * the final object lookup), but more expensive for OFS deltas (we - * have to load the revidx to convert the offset back into a sha1). - */ -static int get_delta_base_oid(struct packed_git *p, - struct pack_window **w_curs, - off_t curpos, - struct object_id *oid, - enum object_type type, - off_t delta_obj_offset) -{ - if (type == OBJ_REF_DELTA) { - unsigned char *base = use_pack(p, w_curs, curpos, NULL); - oidread(oid, base); - return 0; - } else if (type == OBJ_OFS_DELTA) { - struct revindex_entry *revidx; - off_t base_offset = get_delta_base(p, w_curs, &curpos, - type, delta_obj_offset); - - if (!base_offset) - return -1; - - revidx = find_pack_revindex(p, base_offset); - if (!revidx) - return -1; - - return nth_packed_object_id(oid, p, revidx->nr); - } else - return -1; -} - -static int retry_bad_packed_offset(struct repository *r, - struct packed_git *p, - off_t obj_offset) -{ - int type; - struct revindex_entry *revidx; - struct object_id oid; - revidx = find_pack_revindex(p, obj_offset); - if (!revidx) - return OBJ_BAD; - nth_packed_object_id(&oid, p, revidx->nr); - mark_bad_packed_object(p, oid.hash); - type = oid_object_info(r, &oid, NULL); - if (type <= OBJ_NONE) - return OBJ_BAD; - return type; -} - -#define POI_STACK_PREALLOC 64 - -static enum object_type packed_to_object_type(struct repository *r, - struct packed_git *p, - off_t obj_offset, - enum object_type type, - struct pack_window **w_curs, - off_t curpos) -{ - 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; - - while (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) { - off_t base_offset; - unsigned long size; - /* 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); - ALLOC_ARRAY(poi_stack, poi_stack_alloc); - COPY_ARRAY(poi_stack, small_poi_stack, 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(r, p, base_offset); - if (type > OBJ_NONE) - goto out; - goto unwind; - } - } - - switch (type) { - case OBJ_BAD: - case OBJ_COMMIT: - case OBJ_TREE: - case OBJ_BLOB: - case OBJ_TAG: - 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); - return type; - -unwind: - while (poi_stack_nr) { - obj_offset = poi_stack[--poi_stack_nr]; - type = retry_bad_packed_offset(r, p, obj_offset); - if (type > OBJ_NONE) - goto out; - } - type = OBJ_BAD; - goto out; -} - -static struct hashmap delta_base_cache; -static size_t delta_base_cached; - -static LIST_HEAD(delta_base_cache_lru); - -struct delta_base_cache_key { - struct packed_git *p; - off_t base_offset; -}; - -struct delta_base_cache_entry { - struct hashmap_entry ent; - struct delta_base_cache_key key; - struct list_head lru; - void *data; - unsigned long size; - enum object_type type; -}; - -static unsigned int pack_entry_hash(struct packed_git *p, off_t base_offset) -{ - unsigned int hash; - - hash = (unsigned int)(intptr_t)p + (unsigned int)base_offset; - hash += (hash >> 8) + (hash >> 16); - return hash; -} - -static struct delta_base_cache_entry * -get_delta_base_cache_entry(struct packed_git *p, off_t base_offset) -{ - struct hashmap_entry entry, *e; - struct delta_base_cache_key key; - - if (!delta_base_cache.cmpfn) - return NULL; - - hashmap_entry_init(&entry, pack_entry_hash(p, base_offset)); - key.p = p; - key.base_offset = base_offset; - e = hashmap_get(&delta_base_cache, &entry, &key); - return e ? container_of(e, struct delta_base_cache_entry, ent) : NULL; -} - -static int delta_base_cache_key_eq(const struct delta_base_cache_key *a, - const struct delta_base_cache_key *b) -{ - return a->p == b->p && a->base_offset == b->base_offset; -} - -static int delta_base_cache_hash_cmp(const void *unused_cmp_data, - const struct hashmap_entry *va, - const struct hashmap_entry *vb, - const void *vkey) -{ - const struct delta_base_cache_entry *a, *b; - const struct delta_base_cache_key *key = vkey; - - a = container_of(va, const struct delta_base_cache_entry, ent); - b = container_of(vb, const struct delta_base_cache_entry, ent); - - if (key) - return !delta_base_cache_key_eq(&a->key, key); - else - return !delta_base_cache_key_eq(&a->key, &b->key); -} - -static int in_delta_base_cache(struct packed_git *p, off_t base_offset) -{ - return !!get_delta_base_cache_entry(p, base_offset); -} - -/* - * Remove the entry from the cache, but do _not_ free the associated - * entry data. The caller takes ownership of the "data" buffer, and - * should copy out any fields it wants before detaching. - */ -static void detach_delta_base_cache_entry(struct delta_base_cache_entry *ent) -{ - hashmap_remove(&delta_base_cache, &ent->ent, &ent->key); - list_del(&ent->lru); - delta_base_cached -= ent->size; - free(ent); -} - -static void *cache_or_unpack_entry(struct repository *r, struct packed_git *p, - off_t base_offset, unsigned long *base_size, - enum object_type *type) -{ - struct delta_base_cache_entry *ent; - - ent = get_delta_base_cache_entry(p, base_offset); - if (!ent) - return unpack_entry(r, p, base_offset, type, base_size); - - if (type) - *type = ent->type; - if (base_size) - *base_size = ent->size; - return xmemdupz(ent->data, ent->size); -} - -static inline void release_delta_base_cache(struct delta_base_cache_entry *ent) -{ - free(ent->data); - detach_delta_base_cache_entry(ent); -} - -void clear_delta_base_cache(void) -{ - struct list_head *lru, *tmp; - list_for_each_safe(lru, tmp, &delta_base_cache_lru) { - struct delta_base_cache_entry *entry = - list_entry(lru, struct delta_base_cache_entry, lru); - release_delta_base_cache(entry); - } -} - -static void add_delta_base_cache(struct packed_git *p, off_t base_offset, - void *base, unsigned long base_size, enum object_type type) -{ - struct delta_base_cache_entry *ent; - struct list_head *lru, *tmp; - - /* - * Check required to avoid redundant entries when more than one thread - * is unpacking the same object, in unpack_entry() (since its phases I - * and III might run concurrently across multiple threads). - */ - if (in_delta_base_cache(p, base_offset)) { - free(base); - return; - } - - delta_base_cached += base_size; - - list_for_each_safe(lru, tmp, &delta_base_cache_lru) { - struct delta_base_cache_entry *f = - list_entry(lru, struct delta_base_cache_entry, lru); - if (delta_base_cached <= delta_base_cache_limit) - break; - release_delta_base_cache(f); - } - - ent = xmalloc(sizeof(*ent)); - ent->key.p = p; - ent->key.base_offset = base_offset; - ent->type = type; - ent->data = base; - ent->size = base_size; - list_add_tail(&ent->lru, &delta_base_cache_lru); - - if (!delta_base_cache.cmpfn) - hashmap_init(&delta_base_cache, delta_base_cache_hash_cmp, NULL, 0); - hashmap_entry_init(&ent->ent, pack_entry_hash(p, base_offset)); - hashmap_add(&delta_base_cache, &ent->ent); -} - -int packed_object_info(struct repository *r, struct packed_git *p, - off_t obj_offset, struct object_info *oi) -{ - struct pack_window *w_curs = NULL; - unsigned long size; - off_t curpos = obj_offset; - enum object_type type; - - /* - * We always get the representation type, but only convert it to - * a "real" type later if the caller is interested. - */ - if (oi->contentp) { - *oi->contentp = cache_or_unpack_entry(r, p, obj_offset, oi->sizep, - &type); - if (!*oi->contentp) - type = OBJ_BAD; - } else { - type = unpack_object_header(p, &w_curs, &curpos, &size); - } - - if (!oi->contentp && oi->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; - } - *oi->sizep = get_size_from_delta(p, &w_curs, tmp_pos); - if (*oi->sizep == 0) { - type = OBJ_BAD; - goto out; - } - } else { - *oi->sizep = size; - } - } - - if (oi->disk_sizep) { - struct revindex_entry *revidx = find_pack_revindex(p, obj_offset); - *oi->disk_sizep = revidx[1].offset - obj_offset; - } - - if (oi->typep || oi->type_name) { - enum object_type ptot; - ptot = packed_to_object_type(r, p, obj_offset, - type, &w_curs, curpos); - if (oi->typep) - *oi->typep = ptot; - if (oi->type_name) { - const char *tn = type_name(ptot); - if (tn) - strbuf_addstr(oi->type_name, tn); - } - if (ptot < 0) { - type = OBJ_BAD; - goto out; - } - } - - if (oi->delta_base_oid) { - if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) { - if (get_delta_base_oid(p, &w_curs, curpos, - oi->delta_base_oid, - type, obj_offset) < 0) { - type = OBJ_BAD; - goto out; - } - } else - oidclr(oi->delta_base_oid); - } - - oi->whence = in_delta_base_cache(p, obj_offset) ? OI_DBCACHED : - OI_PACKED; - -out: - unuse_pack(&w_curs); - return type; -} - -static void *unpack_compressed_entry(struct packed_git *p, - struct pack_window **w_curs, - off_t curpos, - unsigned long size) -{ - int st; - git_zstream stream; - unsigned char *buffer, *in; - - buffer = xmallocz_gently(size); - if (!buffer) - return NULL; - memset(&stream, 0, sizeof(stream)); - stream.next_out = buffer; - stream.avail_out = size + 1; - - git_inflate_init(&stream); - do { - in = use_pack(p, w_curs, curpos, &stream.avail_in); - stream.next_in = in; - /* - * Note: we must ensure the window section returned by - * use_pack() will be available throughout git_inflate()'s - * unlocked execution. Please refer to the comment at - * get_size_from_delta() to see how this is done. - */ - obj_read_unlock(); - st = git_inflate(&stream, Z_FINISH); - obj_read_lock(); - if (!stream.avail_out) - break; /* the payload is larger than it should be */ - curpos += stream.next_in - in; - } while (st == Z_OK || st == Z_BUF_ERROR); - git_inflate_end(&stream); - if ((st != Z_STREAM_END) || stream.total_out != size) { - free(buffer); - return NULL; - } - - /* versions of zlib can clobber unconsumed portion of outbuf */ - buffer[size] = '\0'; - - return buffer; -} - -static void write_pack_access_log(struct packed_git *p, off_t obj_offset) -{ - static struct trace_key pack_access = TRACE_KEY_INIT(PACK_ACCESS); - trace_printf_key(&pack_access, "%s %"PRIuMAX"\n", - p->pack_name, (uintmax_t)obj_offset); -} - -int do_check_packed_object_crc; - -#define UNPACK_ENTRY_STACK_PREALLOC 64 -struct unpack_entry_stack_ent { - off_t obj_offset; - off_t curpos; - unsigned long size; -}; - -static void *read_object(struct repository *r, - const struct object_id *oid, - enum object_type *type, - unsigned long *size) -{ - struct object_info oi = OBJECT_INFO_INIT; - void *content; - oi.typep = type; - oi.sizep = size; - oi.contentp = &content; - - if (oid_object_info_extended(r, oid, &oi, 0) < 0) - return NULL; - return content; -} - -void *unpack_entry(struct repository *r, struct packed_git *p, off_t obj_offset, - enum object_type *final_type, unsigned long *final_size) -{ - struct pack_window *w_curs = NULL; - off_t curpos = obj_offset; - void *data = NULL; - unsigned long size; - enum object_type type; - struct unpack_entry_stack_ent small_delta_stack[UNPACK_ENTRY_STACK_PREALLOC]; - struct unpack_entry_stack_ent *delta_stack = small_delta_stack; - int delta_stack_nr = 0, delta_stack_alloc = UNPACK_ENTRY_STACK_PREALLOC; - int base_from_cache = 0; - - write_pack_access_log(p, obj_offset); - - /* PHASE 1: drill down to the innermost base object */ - for (;;) { - off_t base_offset; - int i; - struct delta_base_cache_entry *ent; - - ent = get_delta_base_cache_entry(p, curpos); - if (ent) { - type = ent->type; - data = ent->data; - size = ent->size; - detach_delta_base_cache_entry(ent); - base_from_cache = 1; - break; - } - - if (do_check_packed_object_crc && p->index_version > 1) { - struct revindex_entry *revidx = find_pack_revindex(p, obj_offset); - off_t len = revidx[1].offset - obj_offset; - if (check_pack_crc(p, &w_curs, obj_offset, len, revidx->nr)) { - struct object_id oid; - nth_packed_object_id(&oid, p, revidx->nr); - error("bad packed object CRC for %s", - oid_to_hex(&oid)); - mark_bad_packed_object(p, oid.hash); - data = NULL; - goto out; - } - } - - type = unpack_object_header(p, &w_curs, &curpos, &size); - if (type != OBJ_OFS_DELTA && type != OBJ_REF_DELTA) - break; - - base_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset); - if (!base_offset) { - error("failed to validate delta base reference " - "at offset %"PRIuMAX" from %s", - (uintmax_t)curpos, p->pack_name); - /* bail to phase 2, in hopes of recovery */ - data = NULL; - break; - } - - /* push object, proceed to base */ - if (delta_stack_nr >= delta_stack_alloc - && delta_stack == small_delta_stack) { - delta_stack_alloc = alloc_nr(delta_stack_nr); - ALLOC_ARRAY(delta_stack, delta_stack_alloc); - COPY_ARRAY(delta_stack, small_delta_stack, - delta_stack_nr); - } else { - ALLOC_GROW(delta_stack, delta_stack_nr+1, delta_stack_alloc); - } - i = delta_stack_nr++; - delta_stack[i].obj_offset = obj_offset; - delta_stack[i].curpos = curpos; - delta_stack[i].size = size; - - curpos = obj_offset = base_offset; - } - - /* PHASE 2: handle the base */ - switch (type) { - case OBJ_OFS_DELTA: - case OBJ_REF_DELTA: - if (data) - BUG("unpack_entry: left loop at a valid delta"); - break; - case OBJ_COMMIT: - case OBJ_TREE: - case OBJ_BLOB: - case OBJ_TAG: - if (!base_from_cache) - data = unpack_compressed_entry(p, &w_curs, curpos, size); - break; - default: - data = NULL; - error("unknown object type %i at offset %"PRIuMAX" in %s", - type, (uintmax_t)obj_offset, p->pack_name); - } - - /* PHASE 3: apply deltas in order */ - - /* invariants: - * 'data' holds the base data, or NULL if there was corruption - */ - while (delta_stack_nr) { - void *delta_data; - void *base = data; - void *external_base = NULL; - unsigned long delta_size, base_size = size; - int i; - off_t base_obj_offset = obj_offset; - - data = NULL; - - if (!base) { - /* - * We're probably in deep shit, but let's try to fetch - * the required base anyway from another pack or loose. - * This is costly but should happen only in the presence - * of a corrupted pack, and is better than failing outright. - */ - struct revindex_entry *revidx; - struct object_id base_oid; - revidx = find_pack_revindex(p, obj_offset); - if (revidx) { - nth_packed_object_id(&base_oid, p, revidx->nr); - error("failed to read delta base object %s" - " at offset %"PRIuMAX" from %s", - oid_to_hex(&base_oid), (uintmax_t)obj_offset, - p->pack_name); - mark_bad_packed_object(p, base_oid.hash); - base = read_object(r, &base_oid, &type, &base_size); - external_base = base; - } - } - - i = --delta_stack_nr; - obj_offset = delta_stack[i].obj_offset; - curpos = delta_stack[i].curpos; - delta_size = delta_stack[i].size; - - if (!base) - continue; - - delta_data = unpack_compressed_entry(p, &w_curs, curpos, delta_size); - - if (!delta_data) { - error("failed to unpack compressed delta " - "at offset %"PRIuMAX" from %s", - (uintmax_t)curpos, p->pack_name); - data = NULL; - } else { - data = patch_delta(base, base_size, delta_data, - delta_size, &size); - - /* - * We could not apply the delta; warn the user, but - * keep going. Our failure will be noticed either in - * the next iteration of the loop, or if this is the - * final delta, in the caller when we return NULL. - * Those code paths will take care of making a more - * explicit warning and retrying with another copy of - * the object. - */ - if (!data) - error("failed to apply delta"); - } - - /* - * We delay adding `base` to the cache until the end of the loop - * because unpack_compressed_entry() momentarily releases the - * obj_read_mutex, giving another thread the chance to access - * the cache. Therefore, if `base` was already there, this other - * thread could free() it (e.g. to make space for another entry) - * before we are done using it. - */ - if (!external_base) - add_delta_base_cache(p, base_obj_offset, base, base_size, type); - - free(delta_data); - free(external_base); - } - - if (final_type) - *final_type = type; - if (final_size) - *final_size = size; - -out: - unuse_pack(&w_curs); - - if (delta_stack != small_delta_stack) - free(delta_stack); - - return data; -} - -int bsearch_pack(const struct object_id *oid, const struct packed_git *p, uint32_t *result) -{ - const unsigned char *index_fanout = p->index_data; - const unsigned char *index_lookup; - const unsigned int hashsz = the_hash_algo->rawsz; - int index_lookup_width; - - if (!index_fanout) - BUG("bsearch_pack called without a valid pack-index"); - - index_lookup = index_fanout + 4 * 256; - if (p->index_version == 1) { - index_lookup_width = hashsz + 4; - index_lookup += 4; - } else { - index_lookup_width = hashsz; - index_fanout += 8; - index_lookup += 8; - } - - return bsearch_hash(oid->hash, (const uint32_t*)index_fanout, - index_lookup, index_lookup_width, result); -} - -int nth_packed_object_id(struct object_id *oid, - struct packed_git *p, - uint32_t n) -{ - const unsigned char *index = p->index_data; - const unsigned int hashsz = the_hash_algo->rawsz; - if (!index) { - if (open_pack_index(p)) - return -1; - index = p->index_data; - } - if (n >= p->num_objects) - return -1; - index += 4 * 256; - if (p->index_version == 1) { - oidread(oid, index + (hashsz + 4) * n + 4); - } else { - index += 8; - oidread(oid, index + hashsz * n); - } - return 0; -} - -void check_pack_index_ptr(const struct packed_git *p, const void *vptr) -{ - const unsigned char *ptr = vptr; - const unsigned char *start = p->index_data; - const unsigned char *end = start + p->index_size; - if (ptr < start) - die(_("offset before start of pack index for %s (corrupt index?)"), - p->pack_name); - /* No need to check for underflow; .idx files must be at least 8 bytes */ - if (ptr >= end - 8) - die(_("offset beyond end of pack index for %s (truncated index?)"), - p->pack_name); -} - -off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n) -{ - const unsigned char *index = p->index_data; - const unsigned int hashsz = the_hash_algo->rawsz; - index += 4 * 256; - if (p->index_version == 1) { - return ntohl(*((uint32_t *)(index + (hashsz + 4) * n))); - } else { - uint32_t off; - index += 8 + p->num_objects * (hashsz + 4); - off = ntohl(*((uint32_t *)(index + 4 * n))); - if (!(off & 0x80000000)) - return off; - index += p->num_objects * 4 + (off & 0x7fffffff) * 8; - check_pack_index_ptr(p, index); - return get_be64(index); - } -} - -off_t find_pack_entry_one(const unsigned char *sha1, - struct packed_git *p) -{ - const unsigned char *index = p->index_data; - struct object_id oid; - uint32_t result; - - if (!index) { - if (open_pack_index(p)) - return 0; - } - - hashcpy(oid.hash, sha1); - if (bsearch_pack(&oid, p, &result)) - return nth_packed_object_offset(p, result); - return 0; -} - -int is_pack_valid(struct packed_git *p) -{ - /* An already open pack is known to be valid. */ - if (p->pack_fd != -1) - return 1; - - /* If the pack has one window completely covering the - * file size, the pack is known to be valid even if - * the descriptor is not currently open. - */ - if (p->windows) { - struct pack_window *w = p->windows; - - if (!w->offset && w->len == p->pack_size) - return 1; - } - - /* Force the pack to open to prove its valid. */ - return !open_packed_git(p); -} - -struct packed_git *find_sha1_pack(const unsigned char *sha1, - struct packed_git *packs) -{ - struct packed_git *p; - - for (p = packs; p; p = p->next) { - if (find_pack_entry_one(sha1, p)) - return p; - } - return NULL; - -} - -static int fill_pack_entry(const struct object_id *oid, - struct pack_entry *e, - struct packed_git *p) -{ - off_t offset; - - if (p->num_bad_objects) { - unsigned i; - for (i = 0; i < p->num_bad_objects; i++) - if (hasheq(oid->hash, - p->bad_object_sha1 + the_hash_algo->rawsz * i)) - return 0; - } - - offset = find_pack_entry_one(oid->hash, p); - if (!offset) - return 0; - - /* - * We are about to tell the caller where they can locate the - * requested object. We better make sure the packfile is - * still here and can be accessed before supplying that - * answer, as it may have been deleted since the index was - * loaded! - */ - if (!is_pack_valid(p)) - return 0; - e->offset = offset; - e->p = p; - return 1; -} - -int find_pack_entry(struct repository *r, const struct object_id *oid, struct pack_entry *e) -{ - struct list_head *pos; - struct multi_pack_index *m; - - prepare_packed_git(r); - if (!r->objects->packed_git && !r->objects->multi_pack_index) - return 0; - - for (m = r->objects->multi_pack_index; m; m = m->next) { - if (fill_midx_entry(r, oid, e, m)) - return 1; - } - - list_for_each(pos, &r->objects->packed_git_mru) { - struct packed_git *p = list_entry(pos, struct packed_git, mru); - if (!p->multi_pack_index && fill_pack_entry(oid, e, p)) { - list_move(&p->mru, &r->objects->packed_git_mru); - return 1; - } - } - return 0; -} - -int has_object_pack(const struct object_id *oid) -{ - struct pack_entry e; - return find_pack_entry(the_repository, oid, &e); -} - -int has_pack_index(const unsigned char *sha1) -{ - struct stat st; - if (stat(sha1_pack_index_name(sha1), &st)) - return 0; - return 1; -} - -int for_each_object_in_pack(struct packed_git *p, - each_packed_object_fn cb, void *data, - enum for_each_object_flags flags) -{ - uint32_t i; - int r = 0; - - if (flags & FOR_EACH_OBJECT_PACK_ORDER) { - if (load_pack_revindex(p)) - return -1; - } - - for (i = 0; i < p->num_objects; i++) { - uint32_t pos; - struct object_id oid; - - if (flags & FOR_EACH_OBJECT_PACK_ORDER) - pos = p->revindex[i].nr; - else - pos = i; - - if (nth_packed_object_id(&oid, p, pos) < 0) - return error("unable to get sha1 of object %u in %s", - pos, p->pack_name); - - r = cb(&oid, p, pos, data); - if (r) - break; - } - return r; -} - -int for_each_packed_object(each_packed_object_fn cb, void *data, - enum for_each_object_flags flags) -{ - struct packed_git *p; - int r = 0; - int pack_errors = 0; - - prepare_packed_git(the_repository); - for (p = get_all_packs(the_repository); p; p = p->next) { - if ((flags & FOR_EACH_OBJECT_LOCAL_ONLY) && !p->pack_local) - continue; - if ((flags & FOR_EACH_OBJECT_PROMISOR_ONLY) && - !p->pack_promisor) - continue; - if (open_pack_index(p)) { - pack_errors = 1; - continue; - } - r = for_each_object_in_pack(p, cb, data, flags); - if (r) - break; - } - return r ? r : pack_errors; -} - -static int add_promisor_object(const struct object_id *oid, - struct packed_git *pack, - uint32_t pos, - void *set_) -{ - struct oidset *set = set_; - struct object *obj = parse_object(the_repository, oid); - if (!obj) - return 1; - - oidset_insert(set, oid); - - /* - * If this is a tree, commit, or tag, the objects it refers - * to are also promisor objects. (Blobs refer to no objects->) - */ - if (obj->type == OBJ_TREE) { - struct tree *tree = (struct tree *)obj; - struct tree_desc desc; - struct name_entry entry; - if (init_tree_desc_gently(&desc, tree->buffer, tree->size)) - /* - * Error messages are given when packs are - * verified, so do not print any here. - */ - return 0; - while (tree_entry_gently(&desc, &entry)) - oidset_insert(set, &entry.oid); - } else if (obj->type == OBJ_COMMIT) { - struct commit *commit = (struct commit *) obj; - struct commit_list *parents = commit->parents; - - oidset_insert(set, get_commit_tree_oid(commit)); - for (; parents; parents = parents->next) - oidset_insert(set, &parents->item->object.oid); - } else if (obj->type == OBJ_TAG) { - struct tag *tag = (struct tag *) obj; - oidset_insert(set, get_tagged_oid(tag)); - } - return 0; -} - -int is_promisor_object(const struct object_id *oid) -{ - static struct oidset promisor_objects; - static int promisor_objects_prepared; - - if (!promisor_objects_prepared) { - if (has_promisor_remote()) { - for_each_packed_object(add_promisor_object, - &promisor_objects, - FOR_EACH_OBJECT_PROMISOR_ONLY); - } - promisor_objects_prepared = 1; - } - return oidset_contains(&promisor_objects, oid); -} |