diff options
Diffstat (limited to 'sha1_file.c')
| -rw-r--r-- | sha1_file.c | 4028 |
1 files changed, 0 insertions, 4028 deletions
diff --git a/sha1_file.c b/sha1_file.c deleted file mode 100644 index bd5f82e664..0000000000 --- a/sha1_file.c +++ /dev/null @@ -1,4028 +0,0 @@ -/* - * GIT - The information manager from hell - * - * Copyright (C) Linus Torvalds, 2005 - * - * This handles basic git sha1 object files - packing, unpacking, - * creation etc. - */ -#include "cache.h" -#include "config.h" -#include "string-list.h" -#include "lockfile.h" -#include "delta.h" -#include "pack.h" -#include "blob.h" -#include "commit.h" -#include "run-command.h" -#include "tag.h" -#include "tree.h" -#include "tree-walk.h" -#include "refs.h" -#include "pack-revindex.h" -#include "sha1-lookup.h" -#include "bulk-checkin.h" -#include "streaming.h" -#include "dir.h" -#include "mru.h" -#include "list.h" -#include "mergesort.h" -#include "quote.h" - -#define SZ_FMT PRIuMAX -static inline uintmax_t sz_fmt(size_t s) { return s; } - -const unsigned char null_sha1[20]; -const struct object_id null_oid; -const struct object_id empty_tree_oid = { - EMPTY_TREE_SHA1_BIN_LITERAL -}; -const struct object_id empty_blob_oid = { - EMPTY_BLOB_SHA1_BIN_LITERAL -}; - -/* - * This is meant to hold a *small* number of objects that you would - * want read_sha1_file() to be able to return, but yet you do not want - * to write them into the object store (e.g. a browse-only - * application). - */ -static struct cached_object { - unsigned char sha1[20]; - enum object_type type; - void *buf; - unsigned long size; -} *cached_objects; -static int cached_object_nr, cached_object_alloc; - -static struct cached_object empty_tree = { - EMPTY_TREE_SHA1_BIN_LITERAL, - OBJ_TREE, - "", - 0 -}; - -static struct cached_object *find_cached_object(const unsigned char *sha1) -{ - int i; - struct cached_object *co = cached_objects; - - for (i = 0; i < cached_object_nr; i++, co++) { - if (!hashcmp(co->sha1, sha1)) - return co; - } - if (!hashcmp(sha1, empty_tree.sha1)) - return &empty_tree; - return NULL; -} - -int mkdir_in_gitdir(const char *path) -{ - if (mkdir(path, 0777)) { - int saved_errno = errno; - struct stat st; - struct strbuf sb = STRBUF_INIT; - - if (errno != EEXIST) - return -1; - /* - * Are we looking at a path in a symlinked worktree - * whose original repository does not yet have it? - * e.g. .git/rr-cache pointing at its original - * repository in which the user hasn't performed any - * conflict resolution yet? - */ - if (lstat(path, &st) || !S_ISLNK(st.st_mode) || - strbuf_readlink(&sb, path, st.st_size) || - !is_absolute_path(sb.buf) || - mkdir(sb.buf, 0777)) { - strbuf_release(&sb); - errno = saved_errno; - return -1; - } - strbuf_release(&sb); - } - return adjust_shared_perm(path); -} - -enum scld_error safe_create_leading_directories(char *path) -{ - char *next_component = path + offset_1st_component(path); - enum scld_error ret = SCLD_OK; - - while (ret == SCLD_OK && next_component) { - struct stat st; - char *slash = next_component, slash_character; - - while (*slash && !is_dir_sep(*slash)) - slash++; - - if (!*slash) - break; - - next_component = slash + 1; - while (is_dir_sep(*next_component)) - next_component++; - if (!*next_component) - break; - - slash_character = *slash; - *slash = '\0'; - if (!stat(path, &st)) { - /* path exists */ - if (!S_ISDIR(st.st_mode)) { - errno = ENOTDIR; - ret = SCLD_EXISTS; - } - } else if (mkdir(path, 0777)) { - if (errno == EEXIST && - !stat(path, &st) && S_ISDIR(st.st_mode)) - ; /* somebody created it since we checked */ - else if (errno == ENOENT) - /* - * Either mkdir() failed because - * somebody just pruned the containing - * directory, or stat() failed because - * the file that was in our way was - * just removed. Either way, inform - * the caller that it might be worth - * trying again: - */ - ret = SCLD_VANISHED; - else - ret = SCLD_FAILED; - } else if (adjust_shared_perm(path)) { - ret = SCLD_PERMS; - } - *slash = slash_character; - } - return ret; -} - -enum scld_error safe_create_leading_directories_const(const char *path) -{ - int save_errno; - /* path points to cache entries, so xstrdup before messing with it */ - char *buf = xstrdup(path); - enum scld_error result = safe_create_leading_directories(buf); - - save_errno = errno; - free(buf); - errno = save_errno; - return result; -} - -int raceproof_create_file(const char *path, create_file_fn fn, void *cb) -{ - /* - * The number of times we will try to remove empty directories - * in the way of path. This is only 1 because if another - * process is racily creating directories that conflict with - * us, we don't want to fight against them. - */ - int remove_directories_remaining = 1; - - /* - * The number of times that we will try to create the - * directories containing path. We are willing to attempt this - * more than once, because another process could be trying to - * clean up empty directories at the same time as we are - * trying to create them. - */ - int create_directories_remaining = 3; - - /* A scratch copy of path, filled lazily if we need it: */ - struct strbuf path_copy = STRBUF_INIT; - - int ret, save_errno; - - /* Sanity check: */ - assert(*path); - -retry_fn: - ret = fn(path, cb); - save_errno = errno; - if (!ret) - goto out; - - if (errno == EISDIR && remove_directories_remaining-- > 0) { - /* - * A directory is in the way. Maybe it is empty; try - * to remove it: - */ - if (!path_copy.len) - strbuf_addstr(&path_copy, path); - - if (!remove_dir_recursively(&path_copy, REMOVE_DIR_EMPTY_ONLY)) - goto retry_fn; - } else if (errno == ENOENT && create_directories_remaining-- > 0) { - /* - * Maybe the containing directory didn't exist, or - * maybe it was just deleted by a process that is - * racing with us to clean up empty directories. Try - * to create it: - */ - enum scld_error scld_result; - - if (!path_copy.len) - strbuf_addstr(&path_copy, path); - - do { - scld_result = safe_create_leading_directories(path_copy.buf); - if (scld_result == SCLD_OK) - goto retry_fn; - } while (scld_result == SCLD_VANISHED && create_directories_remaining-- > 0); - } - -out: - strbuf_release(&path_copy); - errno = save_errno; - return ret; -} - -static void fill_sha1_path(struct strbuf *buf, const unsigned char *sha1) -{ - int i; - for (i = 0; i < 20; i++) { - static char hex[] = "0123456789abcdef"; - unsigned int val = sha1[i]; - strbuf_addch(buf, hex[val >> 4]); - strbuf_addch(buf, hex[val & 0xf]); - if (!i) - strbuf_addch(buf, '/'); - } -} - -const char *sha1_file_name(const unsigned char *sha1) -{ - static struct strbuf buf = STRBUF_INIT; - - strbuf_reset(&buf); - strbuf_addf(&buf, "%s/", get_object_directory()); - - fill_sha1_path(&buf, sha1); - return buf.buf; -} - -struct strbuf *alt_scratch_buf(struct alternate_object_database *alt) -{ - strbuf_setlen(&alt->scratch, alt->base_len); - return &alt->scratch; -} - -static const char *alt_sha1_path(struct alternate_object_database *alt, - const unsigned char *sha1) -{ - struct strbuf *buf = alt_scratch_buf(alt); - fill_sha1_path(buf, sha1); - return buf->buf; -} - - char *odb_pack_name(struct strbuf *buf, - const unsigned char *sha1, - const char *ext) -{ - strbuf_reset(buf); - strbuf_addf(buf, "%s/pack/pack-%s.%s", get_object_directory(), - sha1_to_hex(sha1), 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"); -} - -struct alternate_object_database *alt_odb_list; -static struct alternate_object_database **alt_odb_tail; - -/* - * Return non-zero iff the path is usable as an alternate object database. - */ -static int alt_odb_usable(struct strbuf *path, const char *normalized_objdir) -{ - struct alternate_object_database *alt; - - /* Detect cases where alternate disappeared */ - if (!is_directory(path->buf)) { - error("object directory %s does not exist; " - "check .git/objects/info/alternates.", - path->buf); - return 0; - } - - /* - * Prevent the common mistake of listing the same - * thing twice, or object directory itself. - */ - for (alt = alt_odb_list; alt; alt = alt->next) { - if (!fspathcmp(path->buf, alt->path)) - return 0; - } - if (!fspathcmp(path->buf, normalized_objdir)) - return 0; - - return 1; -} - -/* - * Prepare alternate object database registry. - * - * The variable alt_odb_list points at the list of struct - * alternate_object_database. The elements on this list come from - * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT - * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates, - * whose contents is similar to that environment variable but can be - * LF separated. Its base points at a statically allocated buffer that - * contains "/the/directory/corresponding/to/.git/objects/...", while - * its name points just after the slash at the end of ".git/objects/" - * in the example above, and has enough space to hold 40-byte hex - * SHA1, an extra slash for the first level indirection, and the - * terminating NUL. - */ -static void read_info_alternates(const char * relative_base, int depth); -static int link_alt_odb_entry(const char *entry, const char *relative_base, - int depth, const char *normalized_objdir) -{ - struct alternate_object_database *ent; - struct strbuf pathbuf = STRBUF_INIT; - - if (!is_absolute_path(entry) && relative_base) { - strbuf_realpath(&pathbuf, relative_base, 1); - strbuf_addch(&pathbuf, '/'); - } - strbuf_addstr(&pathbuf, entry); - - if (strbuf_normalize_path(&pathbuf) < 0 && relative_base) { - error("unable to normalize alternate object path: %s", - pathbuf.buf); - strbuf_release(&pathbuf); - return -1; - } - - /* - * The trailing slash after the directory name is given by - * this function at the end. Remove duplicates. - */ - while (pathbuf.len && pathbuf.buf[pathbuf.len - 1] == '/') - strbuf_setlen(&pathbuf, pathbuf.len - 1); - - if (!alt_odb_usable(&pathbuf, normalized_objdir)) { - strbuf_release(&pathbuf); - return -1; - } - - ent = alloc_alt_odb(pathbuf.buf); - - /* add the alternate entry */ - *alt_odb_tail = ent; - alt_odb_tail = &(ent->next); - ent->next = NULL; - - /* recursively add alternates */ - read_info_alternates(pathbuf.buf, depth + 1); - - strbuf_release(&pathbuf); - return 0; -} - -static const char *parse_alt_odb_entry(const char *string, - int sep, - struct strbuf *out) -{ - const char *end; - - strbuf_reset(out); - - if (*string == '#') { - /* comment; consume up to next separator */ - end = strchrnul(string, sep); - } else if (*string == '"' && !unquote_c_style(out, string, &end)) { - /* - * quoted path; unquote_c_style has copied the - * data for us and set "end". Broken quoting (e.g., - * an entry that doesn't end with a quote) falls - * back to the unquoted case below. - */ - } else { - /* normal, unquoted path */ - end = strchrnul(string, sep); - strbuf_add(out, string, end - string); - } - - if (*end) - end++; - return end; -} - -static void link_alt_odb_entries(const char *alt, int sep, - const char *relative_base, int depth) -{ - struct strbuf objdirbuf = STRBUF_INIT; - struct strbuf entry = STRBUF_INIT; - - if (depth > 5) { - error("%s: ignoring alternate object stores, nesting too deep.", - relative_base); - return; - } - - strbuf_add_absolute_path(&objdirbuf, get_object_directory()); - if (strbuf_normalize_path(&objdirbuf) < 0) - die("unable to normalize object directory: %s", - objdirbuf.buf); - - while (*alt) { - alt = parse_alt_odb_entry(alt, sep, &entry); - if (!entry.len) - continue; - link_alt_odb_entry(entry.buf, relative_base, depth, objdirbuf.buf); - } - strbuf_release(&entry); - strbuf_release(&objdirbuf); -} - -static void read_info_alternates(const char * relative_base, int depth) -{ - char *path; - struct strbuf buf = STRBUF_INIT; - - path = xstrfmt("%s/info/alternates", relative_base); - if (strbuf_read_file(&buf, path, 1024) < 0) { - warn_on_fopen_errors(path); - free(path); - return; - } - - link_alt_odb_entries(buf.buf, '\n', relative_base, depth); - strbuf_release(&buf); - free(path); -} - -struct alternate_object_database *alloc_alt_odb(const char *dir) -{ - struct alternate_object_database *ent; - - FLEX_ALLOC_STR(ent, path, dir); - strbuf_init(&ent->scratch, 0); - strbuf_addf(&ent->scratch, "%s/", dir); - ent->base_len = ent->scratch.len; - - return ent; -} - -void add_to_alternates_file(const char *reference) -{ - struct lock_file *lock = xcalloc(1, sizeof(struct lock_file)); - char *alts = git_pathdup("objects/info/alternates"); - FILE *in, *out; - - hold_lock_file_for_update(lock, alts, LOCK_DIE_ON_ERROR); - out = fdopen_lock_file(lock, "w"); - if (!out) - die_errno("unable to fdopen alternates lockfile"); - - in = fopen(alts, "r"); - if (in) { - struct strbuf line = STRBUF_INIT; - int found = 0; - - while (strbuf_getline(&line, in) != EOF) { - if (!strcmp(reference, line.buf)) { - found = 1; - break; - } - fprintf_or_die(out, "%s\n", line.buf); - } - - strbuf_release(&line); - fclose(in); - - if (found) { - rollback_lock_file(lock); - lock = NULL; - } - } - else if (errno != ENOENT) - die_errno("unable to read alternates file"); - - if (lock) { - fprintf_or_die(out, "%s\n", reference); - if (commit_lock_file(lock)) - die_errno("unable to move new alternates file into place"); - if (alt_odb_tail) - link_alt_odb_entries(reference, '\n', NULL, 0); - } - free(alts); -} - -void add_to_alternates_memory(const char *reference) -{ - /* - * Make sure alternates are initialized, or else our entry may be - * overwritten when they are. - */ - prepare_alt_odb(); - - link_alt_odb_entries(reference, '\n', NULL, 0); -} - -/* - * Compute the exact path an alternate is at and returns it. In case of - * error NULL is returned and the human readable error is added to `err` - * `path` may be relative and should point to $GITDIR. - * `err` must not be null. - */ -char *compute_alternate_path(const char *path, struct strbuf *err) -{ - char *ref_git = NULL; - const char *repo, *ref_git_s; - int seen_error = 0; - - ref_git_s = real_path_if_valid(path); - if (!ref_git_s) { - seen_error = 1; - strbuf_addf(err, _("path '%s' does not exist"), path); - goto out; - } else - /* - * Beware: read_gitfile(), real_path() and mkpath() - * return static buffer - */ - ref_git = xstrdup(ref_git_s); - - repo = read_gitfile(ref_git); - if (!repo) - repo = read_gitfile(mkpath("%s/.git", ref_git)); - if (repo) { - free(ref_git); - ref_git = xstrdup(repo); - } - - if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) { - char *ref_git_git = mkpathdup("%s/.git", ref_git); - free(ref_git); - ref_git = ref_git_git; - } else if (!is_directory(mkpath("%s/objects", ref_git))) { - struct strbuf sb = STRBUF_INIT; - seen_error = 1; - if (get_common_dir(&sb, ref_git)) { - strbuf_addf(err, - _("reference repository '%s' as a linked " - "checkout is not supported yet."), - path); - goto out; - } - - strbuf_addf(err, _("reference repository '%s' is not a " - "local repository."), path); - goto out; - } - - if (!access(mkpath("%s/shallow", ref_git), F_OK)) { - strbuf_addf(err, _("reference repository '%s' is shallow"), - path); - seen_error = 1; - goto out; - } - - if (!access(mkpath("%s/info/grafts", ref_git), F_OK)) { - strbuf_addf(err, - _("reference repository '%s' is grafted"), - path); - seen_error = 1; - goto out; - } - -out: - if (seen_error) { - FREE_AND_NULL(ref_git); - } - - return ref_git; -} - -int foreach_alt_odb(alt_odb_fn fn, void *cb) -{ - struct alternate_object_database *ent; - int r = 0; - - prepare_alt_odb(); - for (ent = alt_odb_list; ent; ent = ent->next) { - r = fn(ent, cb); - if (r) - break; - } - return r; -} - -void prepare_alt_odb(void) -{ - const char *alt; - - if (alt_odb_tail) - return; - - alt = getenv(ALTERNATE_DB_ENVIRONMENT); - if (!alt) alt = ""; - - alt_odb_tail = &alt_odb_list; - link_alt_odb_entries(alt, PATH_SEP, NULL, 0); - - read_info_alternates(get_object_directory(), 0); -} - -/* Returns 1 if we have successfully freshened the file, 0 otherwise. */ -static int freshen_file(const char *fn) -{ - struct utimbuf t; - t.actime = t.modtime = time(NULL); - return !utime(fn, &t); -} - -/* - * All of the check_and_freshen functions return 1 if the file exists and was - * freshened (if freshening was requested), 0 otherwise. If they return - * 0, you should not assume that it is safe to skip a write of the object (it - * either does not exist on disk, or has a stale mtime and may be subject to - * pruning). - */ -int check_and_freshen_file(const char *fn, int freshen) -{ - if (access(fn, F_OK)) - return 0; - if (freshen && !freshen_file(fn)) - return 0; - return 1; -} - -static int check_and_freshen_local(const unsigned char *sha1, int freshen) -{ - return check_and_freshen_file(sha1_file_name(sha1), freshen); -} - -static int check_and_freshen_nonlocal(const unsigned char *sha1, int freshen) -{ - struct alternate_object_database *alt; - prepare_alt_odb(); - for (alt = alt_odb_list; alt; alt = alt->next) { - const char *path = alt_sha1_path(alt, sha1); - if (check_and_freshen_file(path, freshen)) - return 1; - } - return 0; -} - -static int check_and_freshen(const unsigned char *sha1, int freshen) -{ - return check_and_freshen_local(sha1, freshen) || - check_and_freshen_nonlocal(sha1, freshen); -} - -int has_loose_object_nonlocal(const unsigned char *sha1) -{ - return check_and_freshen_nonlocal(sha1, 0); -} - -static int has_loose_object(const unsigned char *sha1) -{ - return check_and_freshen(sha1, 0); -} - -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; -struct packed_git *packed_git; - -static struct mru packed_git_mru_storage; -struct mru *packed_git_mru = &packed_git_mru_storage; - -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; - struct pack_idx_header *hdr; - size_t idx_size; - uint32_t version, nr, i, *index; - int fd = git_open(path); - struct stat st; - - 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 + 20 + 20) { - 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); - - hdr = idx_map; - if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) { - version = ntohl(hdr->idx_version); - if (version < 2 || version > 2) { - munmap(idx_map, idx_size); - 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) { - munmap(idx_map, idx_size); - return error("non-monotonic index %s", path); - } - nr = n; - } - - 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 v1 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; - unsigned long max_size = min_size; - if (nr) - max_size += (nr - 1)*8; - if (idx_size < min_size || idx_size > max_size) { - munmap(idx_map, idx_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)) { - munmap(idx_map, idx_size); - return error("pack too large for current definition of off_t in %s", path); - } - } - - 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)) - die("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; -} - -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 = 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 release_pack_memory(size_t need) -{ - size_t cur = pack_mapped; - while (need >= (cur - pack_mapped) && unuse_one_window(NULL)) - ; /* nothing */ -} - -static void mmap_limit_check(size_t length) -{ - static size_t limit = 0; - if (!limit) { - limit = git_env_ulong("GIT_MMAP_LIMIT", 0); - if (!limit) - limit = SIZE_MAX; - } - if (length > limit) - die("attempting to mmap %"PRIuMAX" over limit %"PRIuMAX, - (uintmax_t)length, (uintmax_t)limit); -} - -void *xmmap_gently(void *start, size_t length, - int prot, int flags, int fd, off_t offset) -{ - void *ret; - - mmap_limit_check(length); - ret = mmap(start, length, prot, flags, fd, offset); - if (ret == MAP_FAILED) { - if (!length) - return NULL; - release_pack_memory(length); - ret = mmap(start, length, prot, flags, fd, offset); - } - return ret; -} - -void *xmmap(void *start, size_t length, - int prot, int flags, int fd, off_t offset) -{ - void *ret = xmmap_gently(start, length, prot, flags, fd, offset); - if (ret == MAP_FAILED) - die_errno("mmap failed"); - return ret; -} - -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); - } -} - -static 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; -} - -static void close_pack(struct packed_git *p) -{ - close_pack_windows(p); - close_pack_fd(p); - close_pack_index(p); -} - -void close_all_packs(void) -{ - struct packed_git *p; - - for (p = packed_git; p; p = p->next) - if (p->do_not_close) - die("BUG: want to close pack marked 'do-not-close'"); - else - close_pack(p); -} - - -/* - * 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 = 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; -} - -void unuse_pack(struct pack_window **w_cursor) -{ - struct pack_window *w = *w_cursor; - if (w) { - w->inuse_cnt--; - *w_cursor = NULL; - } -} - -void close_pack_index(struct packed_git *p) -{ - if (p->index_data) { - munmap((void *)p->index_data, p->index_size); - p->index_data = NULL; - } -} - -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 -} - -/* - * 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 sha1[20]; - unsigned char *idx_sha1; - long fd_flag; - - if (!p->index_data && 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); - - /* We leave these file descriptors open with sliding mmap; - * there is no point keeping them open across exec(), though. - */ - fd_flag = fcntl(p->pack_fd, F_GETFD, 0); - if (fd_flag < 0) - return error("cannot determine file descriptor flags"); - fd_flag |= FD_CLOEXEC; - if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1) - return error("cannot set FD_CLOEXEC"); - - /* Verify we recognize this pack file format. */ - if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != 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)); - - /* 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); - 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)) - return error("packfile %s signature is unavailable", p->pack_name); - idx_sha1 = ((unsigned char *)p->index_data) + p->index_size - 40; - if (hashcmp(sha1, idx_sha1)) - 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 20 bytes (one 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 + 20) <= (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 - 20)) - 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(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; -} - -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; -} - -static void try_to_free_pack_memory(size_t size) -{ - release_pack_memory(size); -} - -struct packed_git *add_packed_git(const char *path, size_t path_len, int local) -{ - static int have_set_try_to_free_routine; - struct stat st; - size_t alloc; - struct packed_git *p; - - if (!have_set_try_to_free_routine) { - have_set_try_to_free_routine = 1; - set_try_to_free_routine(try_to_free_pack_memory); - } - - /* - * Make sure a corresponding .pack file exists and that - * the index looks sane. - */ - if (!strip_suffix_mem(path, &path_len, ".idx")) - return NULL; - - /* - * ".pack" is long enough to hold any suffix we're adding (and - * the use xsnprintf double-checks that) - */ - alloc = st_add3(path_len, strlen(".pack"), 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, ".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 < 40 || get_sha1_hex(path + path_len - 40, p->sha1)) - hashclr(p->sha1); - 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->sha1, sha1); - if (check_packed_git_idx(idx_path, p)) { - free(p); - return NULL; - } - - return p; -} - -void install_packed_git(struct packed_git *pack) -{ - if (pack->pack_fd != -1) - pack_open_fds++; - - pack->next = packed_git; - packed_git = pack; -} - -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); -} - -static void prepare_packed_git_one(char *objdir, int local) -{ - struct strbuf path = STRBUF_INIT; - size_t dirnamelen; - DIR *dir; - struct dirent *de; - struct string_list garbage = STRING_LIST_INIT_DUP; - - 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) { - struct packed_git *p; - size_t base_len; - - if (is_dot_or_dotdot(de->d_name)) - continue; - - strbuf_setlen(&path, dirnamelen); - strbuf_addstr(&path, de->d_name); - - base_len = path.len; - if (strip_suffix_mem(path.buf, &base_len, ".idx")) { - /* Don't reopen a pack we already have. */ - for (p = packed_git; p; p = p->next) { - size_t len; - if (strip_suffix(p->pack_name, ".pack", &len) && - len == base_len && - !memcmp(p->pack_name, path.buf, len)) - break; - } - if (p == NULL && - /* - * See if it really is a valid .idx file with - * corresponding .pack file that we can map. - */ - (p = add_packed_git(path.buf, path.len, local)) != NULL) - install_packed_git(p); - } - - if (!report_garbage) - continue; - - if (ends_with(de->d_name, ".idx") || - ends_with(de->d_name, ".pack") || - ends_with(de->d_name, ".bitmap") || - ends_with(de->d_name, ".keep")) - string_list_append(&garbage, path.buf); - else - report_garbage(PACKDIR_FILE_GARBAGE, path.buf); - } - closedir(dir); - report_pack_garbage(&garbage); - string_list_clear(&garbage, 0); - strbuf_release(&path); -} - -static int approximate_object_count_valid; - -/* - * 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 approximate_object_count(void) -{ - static unsigned long count; - if (!approximate_object_count_valid) { - struct packed_git *p; - - prepare_packed_git(); - count = 0; - for (p = packed_git; p; p = p->next) { - if (open_pack_index(p)) - continue; - count += p->num_objects; - } - } - return 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(void) -{ - packed_git = llist_mergesort(packed_git, get_next_packed_git, - set_next_packed_git, sort_pack); -} - -static void prepare_packed_git_mru(void) -{ - struct packed_git *p; - - mru_clear(packed_git_mru); - for (p = packed_git; p; p = p->next) - mru_append(packed_git_mru, p); -} - -static int prepare_packed_git_run_once = 0; -void prepare_packed_git(void) -{ - struct alternate_object_database *alt; - - if (prepare_packed_git_run_once) - return; - prepare_packed_git_one(get_object_directory(), 1); - prepare_alt_odb(); - for (alt = alt_odb_list; alt; alt = alt->next) - prepare_packed_git_one(alt->path, 0); - rearrange_packed_git(); - prepare_packed_git_mru(); - prepare_packed_git_run_once = 1; -} - -void reprepare_packed_git(void) -{ - approximate_object_count_valid = 0; - prepare_packed_git_run_once = 0; - prepare_packed_git(); -} - -static void mark_bad_packed_object(struct packed_git *p, - const unsigned char *sha1) -{ - unsigned i; - for (i = 0; i < p->num_bad_objects; i++) - if (!hashcmp(sha1, p->bad_object_sha1 + GIT_SHA1_RAWSZ * 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 + GIT_SHA1_RAWSZ * p->num_bad_objects, sha1); - p->num_bad_objects++; -} - -static const struct packed_git *has_packed_and_bad(const unsigned char *sha1) -{ - struct packed_git *p; - unsigned i; - - for (p = packed_git; p; p = p->next) - for (i = 0; i < p->num_bad_objects; i++) - if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i)) - return p; - return NULL; -} - -/* - * With an in-core object data in "map", rehash it to make sure the - * object name actually matches "sha1" to detect object corruption. - * With "map" == NULL, try reading the object named with "sha1" using - * the streaming interface and rehash it to do the same. - */ -int check_sha1_signature(const unsigned char *sha1, void *map, - unsigned long size, const char *type) -{ - unsigned char real_sha1[20]; - enum object_type obj_type; - struct git_istream *st; - git_SHA_CTX c; - char hdr[32]; - int hdrlen; - - if (map) { - hash_sha1_file(map, size, type, real_sha1); - return hashcmp(sha1, real_sha1) ? -1 : 0; - } - - st = open_istream(sha1, &obj_type, &size, NULL); - if (!st) - return -1; - - /* Generate the header */ - hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", typename(obj_type), size) + 1; - - /* Sha1.. */ - git_SHA1_Init(&c); - git_SHA1_Update(&c, hdr, hdrlen); - for (;;) { - char buf[1024 * 16]; - ssize_t readlen = read_istream(st, buf, sizeof(buf)); - - if (readlen < 0) { - close_istream(st); - return -1; - } - if (!readlen) - break; - git_SHA1_Update(&c, buf, readlen); - } - git_SHA1_Final(real_sha1, &c); - close_istream(st); - return hashcmp(sha1, real_sha1) ? -1 : 0; -} - -int git_open_cloexec(const char *name, int flags) -{ - int fd; - static int o_cloexec = O_CLOEXEC; - - fd = open(name, flags | o_cloexec); - if ((o_cloexec & O_CLOEXEC) && fd < 0 && errno == EINVAL) { - /* Try again w/o O_CLOEXEC: the kernel might not support it */ - o_cloexec &= ~O_CLOEXEC; - fd = open(name, flags | o_cloexec); - } - -#if defined(F_GETFD) && defined(F_SETFD) && defined(FD_CLOEXEC) - { - static int fd_cloexec = FD_CLOEXEC; - - if (!o_cloexec && 0 <= fd && fd_cloexec) { - /* Opened w/o O_CLOEXEC? try with fcntl(2) to add it */ - int flags = fcntl(fd, F_GETFD); - if (fcntl(fd, F_SETFD, flags | fd_cloexec)) - fd_cloexec = 0; - } - } -#endif - return fd; -} - -/* - * Find "sha1" as a loose object in the local repository or in an alternate. - * Returns 0 on success, negative on failure. - * - * The "path" out-parameter will give the path of the object we found (if any). - * Note that it may point to static storage and is only valid until another - * call to sha1_file_name(), etc. - */ -static int stat_sha1_file(const unsigned char *sha1, struct stat *st, - const char **path) -{ - struct alternate_object_database *alt; - - *path = sha1_file_name(sha1); - if (!lstat(*path, st)) - return 0; - - prepare_alt_odb(); - errno = ENOENT; - for (alt = alt_odb_list; alt; alt = alt->next) { - *path = alt_sha1_path(alt, sha1); - if (!lstat(*path, st)) - return 0; - } - - return -1; -} - -/* - * Like stat_sha1_file(), but actually open the object and return the - * descriptor. See the caveats on the "path" parameter above. - */ -static int open_sha1_file(const unsigned char *sha1, const char **path) -{ - int fd; - struct alternate_object_database *alt; - int most_interesting_errno; - - *path = sha1_file_name(sha1); - fd = git_open(*path); - if (fd >= 0) - return fd; - most_interesting_errno = errno; - - prepare_alt_odb(); - for (alt = alt_odb_list; alt; alt = alt->next) { - *path = alt_sha1_path(alt, sha1); - fd = git_open(*path); - if (fd >= 0) - return fd; - if (most_interesting_errno == ENOENT) - most_interesting_errno = errno; - } - errno = most_interesting_errno; - return -1; -} - -/* - * Map the loose object at "path" if it is not NULL, or the path found by - * searching for a loose object named "sha1". - */ -static void *map_sha1_file_1(const char *path, - const unsigned char *sha1, - unsigned long *size) -{ - void *map; - int fd; - - if (path) - fd = git_open(path); - else - fd = open_sha1_file(sha1, &path); - map = NULL; - if (fd >= 0) { - struct stat st; - - if (!fstat(fd, &st)) { - *size = xsize_t(st.st_size); - if (!*size) { - /* mmap() is forbidden on empty files */ - error("object file %s is empty", path); - return NULL; - } - map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0); - } - close(fd); - } - return map; -} - -void *map_sha1_file(const unsigned char *sha1, unsigned long *size) -{ - return map_sha1_file_1(NULL, sha1, size); -} - -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; -} - -static int unpack_sha1_short_header(git_zstream *stream, - unsigned char *map, unsigned long mapsize, - void *buffer, unsigned long bufsiz) -{ - /* Get the data stream */ - memset(stream, 0, sizeof(*stream)); - stream->next_in = map; - stream->avail_in = mapsize; - stream->next_out = buffer; - stream->avail_out = bufsiz; - - git_inflate_init(stream); - return git_inflate(stream, 0); -} - -int unpack_sha1_header(git_zstream *stream, - unsigned char *map, unsigned long mapsize, - void *buffer, unsigned long bufsiz) -{ - int status = unpack_sha1_short_header(stream, map, mapsize, - buffer, bufsiz); - - if (status < Z_OK) - return status; - - /* Make sure we have the terminating NUL */ - if (!memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer)) - return -1; - return 0; -} - -static int unpack_sha1_header_to_strbuf(git_zstream *stream, unsigned char *map, - unsigned long mapsize, void *buffer, - unsigned long bufsiz, struct strbuf *header) -{ - int status; - - status = unpack_sha1_short_header(stream, map, mapsize, buffer, bufsiz); - if (status < Z_OK) - return -1; - - /* - * Check if entire header is unpacked in the first iteration. - */ - if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer)) - return 0; - - /* - * buffer[0..bufsiz] was not large enough. Copy the partial - * result out to header, and then append the result of further - * reading the stream. - */ - strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer); - stream->next_out = buffer; - stream->avail_out = bufsiz; - - do { - status = git_inflate(stream, 0); - strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer); - if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer)) - return 0; - stream->next_out = buffer; - stream->avail_out = bufsiz; - } while (status != Z_STREAM_END); - return -1; -} - -static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long size, const unsigned char *sha1) -{ - int bytes = strlen(buffer) + 1; - unsigned char *buf = xmallocz(size); - unsigned long n; - int status = Z_OK; - - n = stream->total_out - bytes; - if (n > size) - n = size; - memcpy(buf, (char *) buffer + bytes, n); - bytes = n; - if (bytes <= size) { - /* - * The above condition must be (bytes <= size), not - * (bytes < size). In other words, even though we - * expect no more output and set avail_out to zero, - * the input zlib stream may have bytes that express - * "this concludes the stream", and we *do* want to - * eat that input. - * - * Otherwise we would not be able to test that we - * consumed all the input to reach the expected size; - * we also want to check that zlib tells us that all - * went well with status == Z_STREAM_END at the end. - */ - stream->next_out = buf + bytes; - stream->avail_out = size - bytes; - while (status == Z_OK) - status = git_inflate(stream, Z_FINISH); - } - if (status == Z_STREAM_END && !stream->avail_in) { - git_inflate_end(stream); - return buf; - } - - if (status < 0) - error("corrupt loose object '%s'", sha1_to_hex(sha1)); - else if (stream->avail_in) - error("garbage at end of loose object '%s'", - sha1_to_hex(sha1)); - free(buf); - return NULL; -} - -/* - * We used to just use "sscanf()", but that's actually way - * too permissive for what we want to check. So do an anal - * object header parse by hand. - */ -static int parse_sha1_header_extended(const char *hdr, struct object_info *oi, - unsigned int flags) -{ - const char *type_buf = hdr; - unsigned long size; - int type, type_len = 0; - - /* - * The type can be of any size but is followed by - * a space. - */ - for (;;) { - char c = *hdr++; - if (!c) - return -1; - if (c == ' ') - break; - type_len++; - } - - type = type_from_string_gently(type_buf, type_len, 1); - if (oi->typename) - strbuf_add(oi->typename, type_buf, type_len); - /* - * Set type to 0 if its an unknown object and - * we're obtaining the type using '--allow-unknown-type' - * option. - */ - if ((flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE) && (type < 0)) - type = 0; - else if (type < 0) - die("invalid object type"); - if (oi->typep) - *oi->typep = type; - - /* - * The length must follow immediately, and be in canonical - * decimal format (ie "010" is not valid). - */ - size = *hdr++ - '0'; - if (size > 9) - return -1; - if (size) { - for (;;) { - unsigned long c = *hdr - '0'; - if (c > 9) - break; - hdr++; - size = size * 10 + c; - } - } - - if (oi->sizep) - *oi->sizep = size; - - /* - * The length must be followed by a zero byte - */ - return *hdr ? -1 : type; -} - -int parse_sha1_header(const char *hdr, unsigned long *sizep) -{ - struct object_info oi = OBJECT_INFO_INIT; - - oi.sizep = sizep; - return parse_sha1_header_extended(hdr, &oi, 0); -} - -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; - st = git_inflate(&stream, Z_FINISH); - 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)); -} - -static 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 += 20; - } 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 const unsigned char *get_delta_base_sha1(struct packed_git *p, - struct pack_window **w_curs, - off_t curpos, - enum object_type type, - off_t delta_obj_offset) -{ - if (type == OBJ_REF_DELTA) { - unsigned char *base = use_pack(p, w_curs, curpos, NULL); - return base; - } 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 NULL; - - revidx = find_pack_revindex(p, base_offset); - if (!revidx) - return NULL; - - return nth_packed_object_sha1(p, revidx->nr); - } else - return NULL; -} - -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; -} - -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 enum object_type packed_to_object_type(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); - 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_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(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 hash; - 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; - 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; - return hashmap_get(&delta_base_cache, &entry, &key); -} - -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 void *va, const void *vb, - const void *vkey) -{ - const struct delta_base_cache_entry *a = va, *b = vb; - const struct delta_base_cache_key *key = vkey; - 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->key); - list_del(&ent->lru); - delta_base_cached -= ent->size; - free(ent); -} - -static void *cache_or_unpack_entry(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(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 = xmalloc(sizeof(*ent)); - struct list_head *lru, *tmp; - - 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->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, pack_entry_hash(p, base_offset)); - hashmap_add(&delta_base_cache, ent); -} - -int packed_object_info(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(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->typename) { - enum object_type ptot; - ptot = packed_to_object_type(p, obj_offset, type, &w_curs, - curpos); - if (oi->typep) - *oi->typep = ptot; - if (oi->typename) { - const char *tn = typename(ptot); - if (tn) - strbuf_addstr(oi->typename, tn); - } - if (ptot < 0) { - type = OBJ_BAD; - goto out; - } - } - - if (oi->delta_base_sha1) { - if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) { - const unsigned char *base; - - base = get_delta_base_sha1(p, &w_curs, curpos, - type, obj_offset); - if (!base) { - type = OBJ_BAD; - goto out; - } - - hashcpy(oi->delta_base_sha1, base); - } else - hashclr(oi->delta_base_sha1); - } - -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; - st = git_inflate(&stream, Z_FINISH); - 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; - } - - return buffer; -} - -static void *read_object(const unsigned char *sha1, enum object_type *type, - unsigned long *size); - -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; -}; - -void *unpack_entry(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)) { - const unsigned char *sha1 = - nth_packed_object_sha1(p, revidx->nr); - error("bad packed object CRC for %s", - sha1_to_hex(sha1)); - mark_bad_packed_object(p, sha1); - 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); - memcpy(delta_stack, small_delta_stack, - sizeof(*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) - die("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; - - data = NULL; - - if (base) - add_delta_base_cache(p, obj_offset, base, base_size, type); - - 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; - const unsigned char *base_sha1; - revidx = find_pack_revindex(p, obj_offset); - if (revidx) { - base_sha1 = nth_packed_object_sha1(p, revidx->nr); - error("failed to read delta base object %s" - " at offset %"PRIuMAX" from %s", - sha1_to_hex(base_sha1), (uintmax_t)obj_offset, - p->pack_name); - mark_bad_packed_object(p, base_sha1); - base = read_object(base_sha1, &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; - free(external_base); - continue; - } - - 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"); - - 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; -} - -const unsigned char *nth_packed_object_sha1(struct packed_git *p, - uint32_t n) -{ - const unsigned char *index = p->index_data; - if (!index) { - if (open_pack_index(p)) - return NULL; - 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; - } -} - -const struct object_id *nth_packed_object_oid(struct object_id *oid, - struct packed_git *p, - uint32_t n) -{ - const unsigned char *hash = nth_packed_object_sha1(p, n); - if (!hash) - return NULL; - hashcpy(oid->hash, hash); - return oid; -} - -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; - index += 4 * 256; - 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; - check_pack_index_ptr(p, index); - 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; - const unsigned char *index = p->index_data; - unsigned hi, lo, stride; - static int debug_lookup = -1; - - if (debug_lookup < 0) - debug_lookup = !!getenv("GIT_DEBUG_LOOKUP"); - - if (!index) { - if (open_pack_index(p)) - return 0; - level1_ofs = p->index_data; - index = p->index_data; - } - 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])); - if (p->index_version > 1) { - stride = 20; - } else { - stride = 24; - index += 4; - } - - if (debug_lookup) - printf("%02x%02x%02x... lo %u hi %u nr %"PRIu32"\n", - sha1[0], sha1[1], sha1[2], lo, hi, p->num_objects); - - while (lo < hi) { - unsigned mi = (lo + hi) / 2; - int cmp = hashcmp(index + mi * stride, sha1); - - if (debug_lookup) - printf("lo %u hi %u rg %u mi %u\n", - lo, hi, hi - lo, mi); - if (!cmp) - return nth_packed_object_offset(p, mi); - if (cmp > 0) - hi = mi; - else - lo = mi+1; - } - 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); -} - -static int fill_pack_entry(const unsigned char *sha1, - 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 (!hashcmp(sha1, p->bad_object_sha1 + 20 * i)) - return 0; - } - - offset = find_pack_entry_one(sha1, 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; - hashcpy(e->sha1, sha1); - return 1; -} - -/* - * Iff a pack file contains the object named by sha1, return true and - * store its location to e. - */ -static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e) -{ - struct mru_entry *p; - - prepare_packed_git(); - if (!packed_git) - return 0; - - for (p = packed_git_mru->head; p; p = p->next) { - if (fill_pack_entry(sha1, e, p->item)) { - mru_mark(packed_git_mru, p); - return 1; - } - } - return 0; -} - -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 sha1_loose_object_info(const unsigned char *sha1, - struct object_info *oi, - int flags) -{ - int status = 0; - unsigned long mapsize; - void *map; - git_zstream stream; - char hdr[32]; - struct strbuf hdrbuf = STRBUF_INIT; - unsigned long size_scratch; - - if (oi->delta_base_sha1) - hashclr(oi->delta_base_sha1); - - /* - * If we don't care about type or size, then we don't - * need to look inside the object at all. Note that we - * do not optimize out the stat call, even if the - * caller doesn't care about the disk-size, since our - * return value implicitly indicates whether the - * object even exists. - */ - if (!oi->typep && !oi->typename && !oi->sizep && !oi->contentp) { - const char *path; - struct stat st; - if (stat_sha1_file(sha1, &st, &path) < 0) - return -1; - if (oi->disk_sizep) - *oi->disk_sizep = st.st_size; - return 0; - } - - map = map_sha1_file(sha1, &mapsize); - if (!map) - return -1; - - if (!oi->sizep) - oi->sizep = &size_scratch; - - if (oi->disk_sizep) - *oi->disk_sizep = mapsize; - if ((flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE)) { - if (unpack_sha1_header_to_strbuf(&stream, map, mapsize, hdr, sizeof(hdr), &hdrbuf) < 0) - status = error("unable to unpack %s header with --allow-unknown-type", - sha1_to_hex(sha1)); - } else if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0) - status = error("unable to unpack %s header", - sha1_to_hex(sha1)); - if (status < 0) - ; /* Do nothing */ - else if (hdrbuf.len) { - if ((status = parse_sha1_header_extended(hdrbuf.buf, oi, flags)) < 0) - status = error("unable to parse %s header with --allow-unknown-type", - sha1_to_hex(sha1)); - } else if ((status = parse_sha1_header_extended(hdr, oi, flags)) < 0) - status = error("unable to parse %s header", sha1_to_hex(sha1)); - - if (status >= 0 && oi->contentp) { - *oi->contentp = unpack_sha1_rest(&stream, hdr, - *oi->sizep, sha1); - if (!*oi->contentp) { - git_inflate_end(&stream); - status = -1; - } - } else - git_inflate_end(&stream); - - munmap(map, mapsize); - if (status && oi->typep) - *oi->typep = status; - if (oi->sizep == &size_scratch) - oi->sizep = NULL; - strbuf_release(&hdrbuf); - return (status < 0) ? status : 0; -} - -int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi, unsigned flags) -{ - static struct object_info blank_oi = OBJECT_INFO_INIT; - struct pack_entry e; - int rtype; - const unsigned char *real = (flags & OBJECT_INFO_LOOKUP_REPLACE) ? - lookup_replace_object(sha1) : - sha1; - - if (!oi) - oi = &blank_oi; - - if (!(flags & OBJECT_INFO_SKIP_CACHED)) { - struct cached_object *co = find_cached_object(real); - if (co) { - if (oi->typep) - *(oi->typep) = co->type; - if (oi->sizep) - *(oi->sizep) = co->size; - if (oi->disk_sizep) - *(oi->disk_sizep) = 0; - if (oi->delta_base_sha1) - hashclr(oi->delta_base_sha1); - if (oi->typename) - strbuf_addstr(oi->typename, typename(co->type)); - if (oi->contentp) - *oi->contentp = xmemdupz(co->buf, co->size); - oi->whence = OI_CACHED; - return 0; - } - } - - if (!find_pack_entry(real, &e)) { - /* Most likely it's a loose object. */ - if (!sha1_loose_object_info(real, oi, flags)) { - oi->whence = OI_LOOSE; - return 0; - } - - /* Not a loose object; someone else may have just packed it. */ - if (flags & OBJECT_INFO_QUICK) { - return -1; - } else { - reprepare_packed_git(); - if (!find_pack_entry(real, &e)) - return -1; - } - } - - if (oi == &blank_oi) - /* - * We know that the caller doesn't actually need the - * information below, so return early. - */ - return 0; - - rtype = packed_object_info(e.p, e.offset, oi); - if (rtype < 0) { - mark_bad_packed_object(e.p, real); - return sha1_object_info_extended(real, oi, 0); - } else if (in_delta_base_cache(e.p, e.offset)) { - oi->whence = OI_DBCACHED; - } else { - oi->whence = OI_PACKED; - oi->u.packed.offset = e.offset; - oi->u.packed.pack = e.p; - oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA || - rtype == OBJ_OFS_DELTA); - } - - return 0; -} - -/* returns enum object_type or negative */ -int sha1_object_info(const unsigned char *sha1, unsigned long *sizep) -{ - enum object_type type; - struct object_info oi = OBJECT_INFO_INIT; - - oi.typep = &type; - oi.sizep = sizep; - if (sha1_object_info_extended(sha1, &oi, - OBJECT_INFO_LOOKUP_REPLACE) < 0) - return -1; - return type; -} - -static void *read_packed_sha1(const unsigned char *sha1, - enum object_type *type, unsigned long *size) -{ - struct pack_entry e; - void *data; - - if (!find_pack_entry(sha1, &e)) - return NULL; - data = cache_or_unpack_entry(e.p, e.offset, size, type); - if (!data) { - /* - * We're probably in deep shit, but let's try to fetch - * the required object anyway from another pack or loose. - * This should happen only in the presence of a corrupted - * pack, and is better than failing outright. - */ - error("failed to read object %s at offset %"PRIuMAX" from %s", - sha1_to_hex(sha1), (uintmax_t)e.offset, e.p->pack_name); - mark_bad_packed_object(e.p, sha1); - data = read_object(sha1, type, size); - } - return data; -} - -int pretend_sha1_file(void *buf, unsigned long len, enum object_type type, - unsigned char *sha1) -{ - struct cached_object *co; - - hash_sha1_file(buf, len, typename(type), sha1); - if (has_sha1_file(sha1) || find_cached_object(sha1)) - return 0; - ALLOC_GROW(cached_objects, cached_object_nr + 1, cached_object_alloc); - co = &cached_objects[cached_object_nr++]; - co->size = len; - co->type = type; - co->buf = xmalloc(len); - memcpy(co->buf, buf, len); - hashcpy(co->sha1, sha1); - return 0; -} - -static void *read_object(const unsigned char *sha1, 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 (sha1_object_info_extended(sha1, &oi, 0) < 0) - return NULL; - return content; -} - -/* - * This function dies on corrupt objects; the callers who want to - * deal with them should arrange to call read_object() and give error - * messages themselves. - */ -void *read_sha1_file_extended(const unsigned char *sha1, - enum object_type *type, - unsigned long *size, - int lookup_replace) -{ - void *data; - const struct packed_git *p; - const char *path; - struct stat st; - const unsigned char *repl = lookup_replace ? lookup_replace_object(sha1) - : sha1; - - errno = 0; - data = read_object(repl, type, size); - if (data) - return data; - - if (errno && errno != ENOENT) - die_errno("failed to read object %s", sha1_to_hex(sha1)); - - /* die if we replaced an object with one that does not exist */ - if (repl != sha1) - die("replacement %s not found for %s", - sha1_to_hex(repl), sha1_to_hex(sha1)); - - if (!stat_sha1_file(repl, &st, &path)) - die("loose object %s (stored in %s) is corrupt", - sha1_to_hex(repl), path); - - if ((p = has_packed_and_bad(repl)) != NULL) - die("packed object %s (stored in %s) is corrupt", - sha1_to_hex(repl), p->pack_name); - - return NULL; -} - -void *read_object_with_reference(const unsigned char *sha1, - const char *required_type_name, - unsigned long *size, - unsigned char *actual_sha1_return) -{ - enum object_type type, required_type; - void *buffer; - unsigned long isize; - unsigned char actual_sha1[20]; - - required_type = type_from_string(required_type_name); - hashcpy(actual_sha1, sha1); - while (1) { - int ref_length = -1; - const char *ref_type = NULL; - - buffer = read_sha1_file(actual_sha1, &type, &isize); - if (!buffer) - return NULL; - if (type == required_type) { - *size = isize; - if (actual_sha1_return) - hashcpy(actual_sha1_return, actual_sha1); - return buffer; - } - /* Handle references */ - else if (type == OBJ_COMMIT) - ref_type = "tree "; - else if (type == OBJ_TAG) - ref_type = "object "; - else { - free(buffer); - return NULL; - } - ref_length = strlen(ref_type); - - if (ref_length + 40 > isize || - memcmp(buffer, ref_type, ref_length) || - get_sha1_hex((char *) buffer + ref_length, actual_sha1)) { - free(buffer); - return NULL; - } - free(buffer); - /* Now we have the ID of the referred-to object in - * actual_sha1. Check again. */ - } -} - -static void write_sha1_file_prepare(const void *buf, unsigned long len, - const char *type, unsigned char *sha1, - char *hdr, int *hdrlen) -{ - git_SHA_CTX c; - - /* Generate the header */ - *hdrlen = xsnprintf(hdr, *hdrlen, "%s %lu", type, len)+1; - - /* Sha1.. */ - git_SHA1_Init(&c); - git_SHA1_Update(&c, hdr, *hdrlen); - git_SHA1_Update(&c, buf, len); - git_SHA1_Final(sha1, &c); -} - -/* - * Move the just written object into its final resting place. - */ -int finalize_object_file(const char *tmpfile, const char *filename) -{ - int ret = 0; - - if (object_creation_mode == OBJECT_CREATION_USES_RENAMES) - goto try_rename; - else if (link(tmpfile, filename)) - ret = errno; - - /* - * Coda hack - coda doesn't like cross-directory links, - * so we fall back to a rename, which will mean that it - * won't be able to check collisions, but that's not a - * big deal. - * - * The same holds for FAT formatted media. - * - * When this succeeds, we just return. We have nothing - * left to unlink. - */ - if (ret && ret != EEXIST) { - try_rename: - if (!rename(tmpfile, filename)) - goto out; - ret = errno; - } - unlink_or_warn(tmpfile); - if (ret) { - if (ret != EEXIST) { - return error_errno("unable to write sha1 filename %s", filename); - } - /* FIXME!!! Collision check here ? */ - } - -out: - if (adjust_shared_perm(filename)) - return error("unable to set permission to '%s'", filename); - return 0; -} - -static int write_buffer(int fd, const void *buf, size_t len) -{ - if (write_in_full(fd, buf, len) < 0) - return error_errno("file write error"); - return 0; -} - -int hash_sha1_file(const void *buf, unsigned long len, const char *type, - unsigned char *sha1) -{ - char hdr[32]; - int hdrlen = sizeof(hdr); - write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen); - return 0; -} - -/* Finalize a file on disk, and close it. */ -static void close_sha1_file(int fd) -{ - if (fsync_object_files) - fsync_or_die(fd, "sha1 file"); - if (close(fd) != 0) - die_errno("error when closing sha1 file"); -} - -/* Size of directory component, including the ending '/' */ -static inline int directory_size(const char *filename) -{ - const char *s = strrchr(filename, '/'); - if (!s) - return 0; - return s - filename + 1; -} - -/* - * This creates a temporary file in the same directory as the final - * 'filename' - * - * We want to avoid cross-directory filename renames, because those - * can have problems on various filesystems (FAT, NFS, Coda). - */ -static int create_tmpfile(struct strbuf *tmp, const char *filename) -{ - int fd, dirlen = directory_size(filename); - - strbuf_reset(tmp); - strbuf_add(tmp, filename, dirlen); - strbuf_addstr(tmp, "tmp_obj_XXXXXX"); - fd = git_mkstemp_mode(tmp->buf, 0444); - if (fd < 0 && dirlen && errno == ENOENT) { - /* - * Make sure the directory exists; note that the contents - * of the buffer are undefined after mkstemp returns an - * error, so we have to rewrite the whole buffer from - * scratch. - */ - strbuf_reset(tmp); - strbuf_add(tmp, filename, dirlen - 1); - if (mkdir(tmp->buf, 0777) && errno != EEXIST) - return -1; - if (adjust_shared_perm(tmp->buf)) - return -1; - - /* Try again */ - strbuf_addstr(tmp, "/tmp_obj_XXXXXX"); - fd = git_mkstemp_mode(tmp->buf, 0444); - } - return fd; -} - -static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen, - const void *buf, unsigned long len, time_t mtime) -{ - int fd, ret; - unsigned char compressed[4096]; - git_zstream stream; - git_SHA_CTX c; - unsigned char parano_sha1[20]; - static struct strbuf tmp_file = STRBUF_INIT; - const char *filename = sha1_file_name(sha1); - - fd = create_tmpfile(&tmp_file, filename); - if (fd < 0) { - if (errno == EACCES) - return error("insufficient permission for adding an object to repository database %s", get_object_directory()); - else - return error_errno("unable to create temporary file"); - } - - /* Set it up */ - git_deflate_init(&stream, zlib_compression_level); - stream.next_out = compressed; - stream.avail_out = sizeof(compressed); - git_SHA1_Init(&c); - - /* First header.. */ - stream.next_in = (unsigned char *)hdr; - stream.avail_in = hdrlen; - while (git_deflate(&stream, 0) == Z_OK) - ; /* nothing */ - git_SHA1_Update(&c, hdr, hdrlen); - - /* Then the data itself.. */ - stream.next_in = (void *)buf; - stream.avail_in = len; - do { - unsigned char *in0 = stream.next_in; - ret = git_deflate(&stream, Z_FINISH); - git_SHA1_Update(&c, in0, stream.next_in - in0); - if (write_buffer(fd, compressed, stream.next_out - compressed) < 0) - die("unable to write sha1 file"); - stream.next_out = compressed; - stream.avail_out = sizeof(compressed); - } while (ret == Z_OK); - - if (ret != Z_STREAM_END) - die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret); - ret = git_deflate_end_gently(&stream); - if (ret != Z_OK) - die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret); - git_SHA1_Final(parano_sha1, &c); - if (hashcmp(sha1, parano_sha1) != 0) - die("confused by unstable object source data for %s", sha1_to_hex(sha1)); - - close_sha1_file(fd); - - if (mtime) { - struct utimbuf utb; - utb.actime = mtime; - utb.modtime = mtime; - if (utime(tmp_file.buf, &utb) < 0) - warning_errno("failed utime() on %s", tmp_file.buf); - } - - return finalize_object_file(tmp_file.buf, filename); -} - -static int freshen_loose_object(const unsigned char *sha1) -{ - return check_and_freshen(sha1, 1); -} - -static int freshen_packed_object(const unsigned char *sha1) -{ - struct pack_entry e; - if (!find_pack_entry(sha1, &e)) - return 0; - if (e.p->freshened) - return 1; - if (!freshen_file(e.p->pack_name)) - return 0; - e.p->freshened = 1; - return 1; -} - -int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *sha1) -{ - char hdr[32]; - int hdrlen = sizeof(hdr); - - /* Normally if we have it in the pack then we do not bother writing - * it out into .git/objects/??/?{38} file. - */ - write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen); - if (freshen_packed_object(sha1) || freshen_loose_object(sha1)) - return 0; - return write_loose_object(sha1, hdr, hdrlen, buf, len, 0); -} - -int hash_sha1_file_literally(const void *buf, unsigned long len, const char *type, - unsigned char *sha1, unsigned flags) -{ - char *header; - int hdrlen, status = 0; - - /* type string, SP, %lu of the length plus NUL must fit this */ - hdrlen = strlen(type) + 32; - header = xmalloc(hdrlen); - write_sha1_file_prepare(buf, len, type, sha1, header, &hdrlen); - - if (!(flags & HASH_WRITE_OBJECT)) - goto cleanup; - if (freshen_packed_object(sha1) || freshen_loose_object(sha1)) - goto cleanup; - status = write_loose_object(sha1, header, hdrlen, buf, len, 0); - -cleanup: - free(header); - return status; -} - -int force_object_loose(const unsigned char *sha1, time_t mtime) -{ - void *buf; - unsigned long len; - enum object_type type; - char hdr[32]; - int hdrlen; - int ret; - - if (has_loose_object(sha1)) - return 0; - buf = read_packed_sha1(sha1, &type, &len); - if (!buf) - return error("cannot read sha1_file for %s", sha1_to_hex(sha1)); - hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", typename(type), len) + 1; - ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime); - free(buf); - - return ret; -} - -int has_pack_index(const unsigned char *sha1) -{ - struct stat st; - if (stat(sha1_pack_index_name(sha1), &st)) - return 0; - return 1; -} - -int has_sha1_pack(const unsigned char *sha1) -{ - struct pack_entry e; - return find_pack_entry(sha1, &e); -} - -int has_sha1_file_with_flags(const unsigned char *sha1, int flags) -{ - if (!startup_info->have_repository) - return 0; - return sha1_object_info_extended(sha1, NULL, - flags | OBJECT_INFO_SKIP_CACHED) >= 0; -} - -int has_object_file(const struct object_id *oid) -{ - return has_sha1_file(oid->hash); -} - -int has_object_file_with_flags(const struct object_id *oid, int flags) -{ - return has_sha1_file_with_flags(oid->hash, flags); -} - -static void check_tree(const void *buf, size_t size) -{ - struct tree_desc desc; - struct name_entry entry; - - init_tree_desc(&desc, buf, size); - while (tree_entry(&desc, &entry)) - /* do nothing - * tree_entry() will die() on malformed entries */ - ; -} - -static void check_commit(const void *buf, size_t size) -{ - struct commit c; - memset(&c, 0, sizeof(c)); - if (parse_commit_buffer(&c, buf, size)) - die("corrupt commit"); -} - -static void check_tag(const void *buf, size_t size) -{ - struct tag t; - memset(&t, 0, sizeof(t)); - if (parse_tag_buffer(&t, buf, size)) - die("corrupt tag"); -} - -static int index_mem(unsigned char *sha1, void *buf, size_t size, - enum object_type type, - const char *path, unsigned flags) -{ - int ret, re_allocated = 0; - int write_object = flags & HASH_WRITE_OBJECT; - - if (!type) - type = OBJ_BLOB; - - /* - * Convert blobs to git internal format - */ - if ((type == OBJ_BLOB) && path) { - struct strbuf nbuf = STRBUF_INIT; - if (convert_to_git(&the_index, path, buf, size, &nbuf, - write_object ? safe_crlf : SAFE_CRLF_FALSE)) { - buf = strbuf_detach(&nbuf, &size); - re_allocated = 1; - } - } - if (flags & HASH_FORMAT_CHECK) { - if (type == OBJ_TREE) - check_tree(buf, size); - if (type == OBJ_COMMIT) - check_commit(buf, size); - if (type == OBJ_TAG) - check_tag(buf, size); - } - - if (write_object) - ret = write_sha1_file(buf, size, typename(type), sha1); - else - ret = hash_sha1_file(buf, size, typename(type), sha1); - if (re_allocated) - free(buf); - return ret; -} - -static int index_stream_convert_blob(unsigned char *sha1, int fd, - const char *path, unsigned flags) -{ - int ret; - const int write_object = flags & HASH_WRITE_OBJECT; - struct strbuf sbuf = STRBUF_INIT; - - assert(path); - assert(would_convert_to_git_filter_fd(path)); - - convert_to_git_filter_fd(&the_index, path, fd, &sbuf, - write_object ? safe_crlf : SAFE_CRLF_FALSE); - - if (write_object) - ret = write_sha1_file(sbuf.buf, sbuf.len, typename(OBJ_BLOB), - sha1); - else - ret = hash_sha1_file(sbuf.buf, sbuf.len, typename(OBJ_BLOB), - sha1); - strbuf_release(&sbuf); - return ret; -} - -static int index_pipe(unsigned char *sha1, int fd, enum object_type type, - const char *path, unsigned flags) -{ - struct strbuf sbuf = STRBUF_INIT; - int ret; - - if (strbuf_read(&sbuf, fd, 4096) >= 0) - ret = index_mem(sha1, sbuf.buf, sbuf.len, type, path, flags); - else - ret = -1; - strbuf_release(&sbuf); - return ret; -} - -#define SMALL_FILE_SIZE (32*1024) - -static int index_core(unsigned char *sha1, int fd, size_t size, - enum object_type type, const char *path, - unsigned flags) -{ - int ret; - - if (!size) { - ret = index_mem(sha1, "", size, type, path, flags); - } else if (size <= SMALL_FILE_SIZE) { - char *buf = xmalloc(size); - if (size == read_in_full(fd, buf, size)) - ret = index_mem(sha1, buf, size, type, path, flags); - else - ret = error_errno("short read"); - free(buf); - } else { - void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0); - ret = index_mem(sha1, buf, size, type, path, flags); - munmap(buf, size); - } - return ret; -} - -/* - * This creates one packfile per large blob unless bulk-checkin - * machinery is "plugged". - * - * This also bypasses the usual "convert-to-git" dance, and that is on - * purpose. We could write a streaming version of the converting - * functions and insert that before feeding the data to fast-import - * (or equivalent in-core API described above). However, that is - * somewhat complicated, as we do not know the size of the filter - * result, which we need to know beforehand when writing a git object. - * Since the primary motivation for trying to stream from the working - * tree file and to avoid mmaping it in core is to deal with large - * binary blobs, they generally do not want to get any conversion, and - * callers should avoid this code path when filters are requested. - */ -static int index_stream(unsigned char *sha1, int fd, size_t size, - enum object_type type, const char *path, - unsigned flags) -{ - return index_bulk_checkin(sha1, fd, size, type, path, flags); -} - -int index_fd(unsigned char *sha1, int fd, struct stat *st, - enum object_type type, const char *path, unsigned flags) -{ - int ret; - - /* - * Call xsize_t() only when needed to avoid potentially unnecessary - * die() for large files. - */ - if (type == OBJ_BLOB && path && would_convert_to_git_filter_fd(path)) - ret = index_stream_convert_blob(sha1, fd, path, flags); - else if (!S_ISREG(st->st_mode)) - ret = index_pipe(sha1, fd, type, path, flags); - else if (st->st_size <= big_file_threshold || type != OBJ_BLOB || - (path && would_convert_to_git(&the_index, path))) - ret = index_core(sha1, fd, xsize_t(st->st_size), type, path, - flags); - else - ret = index_stream(sha1, fd, xsize_t(st->st_size), type, path, - flags); - close(fd); - return ret; -} - -int index_path(unsigned char *sha1, const char *path, struct stat *st, unsigned flags) -{ - int fd; - struct strbuf sb = STRBUF_INIT; - - switch (st->st_mode & S_IFMT) { - case S_IFREG: - fd = open(path, O_RDONLY); - if (fd < 0) - return error_errno("open(\"%s\")", path); - if (index_fd(sha1, fd, st, OBJ_BLOB, path, flags) < 0) - return error("%s: failed to insert into database", - path); - break; - case S_IFLNK: - if (strbuf_readlink(&sb, path, st->st_size)) - return error_errno("readlink(\"%s\")", path); - if (!(flags & HASH_WRITE_OBJECT)) - hash_sha1_file(sb.buf, sb.len, blob_type, sha1); - else if (write_sha1_file(sb.buf, sb.len, blob_type, sha1)) - return error("%s: failed to insert into database", - path); - strbuf_release(&sb); - break; - case S_IFDIR: - return resolve_gitlink_ref(path, "HEAD", sha1); - default: - return error("%s: unsupported file type", path); - } - return 0; -} - -int read_pack_header(int fd, struct pack_header *header) -{ - if (read_in_full(fd, header, sizeof(*header)) != sizeof(*header)) - /* "eof before pack header was fully read" */ - return PH_ERROR_EOF; - - if (header->hdr_signature != htonl(PACK_SIGNATURE)) - /* "protocol error (pack signature mismatch detected)" */ - return PH_ERROR_PACK_SIGNATURE; - if (!pack_version_ok(header->hdr_version)) - /* "protocol error (pack version unsupported)" */ - return PH_ERROR_PROTOCOL; - return 0; -} - -void assert_sha1_type(const unsigned char *sha1, enum object_type expect) -{ - enum object_type type = sha1_object_info(sha1, NULL); - if (type < 0) - die("%s is not a valid object", sha1_to_hex(sha1)); - if (type != expect) - die("%s is not a valid '%s' object", sha1_to_hex(sha1), - typename(expect)); -} - -int for_each_file_in_obj_subdir(unsigned int subdir_nr, - struct strbuf *path, - each_loose_object_fn obj_cb, - each_loose_cruft_fn cruft_cb, - each_loose_subdir_fn subdir_cb, - void *data) -{ - size_t origlen, baselen; - DIR *dir; - struct dirent *de; - int r = 0; - - if (subdir_nr > 0xff) - BUG("invalid loose object subdirectory: %x", subdir_nr); - - origlen = path->len; - strbuf_complete(path, '/'); - strbuf_addf(path, "%02x", subdir_nr); - baselen = path->len; - - dir = opendir(path->buf); - if (!dir) { - if (errno != ENOENT) - r = error_errno("unable to open %s", path->buf); - strbuf_setlen(path, origlen); - return r; - } - - while ((de = readdir(dir))) { - if (is_dot_or_dotdot(de->d_name)) - continue; - - strbuf_setlen(path, baselen); - strbuf_addf(path, "/%s", de->d_name); - - if (strlen(de->d_name) == GIT_SHA1_HEXSZ - 2) { - char hex[GIT_MAX_HEXSZ+1]; - struct object_id oid; - - xsnprintf(hex, sizeof(hex), "%02x%s", - subdir_nr, de->d_name); - if (!get_oid_hex(hex, &oid)) { - if (obj_cb) { - r = obj_cb(&oid, path->buf, data); - if (r) - break; - } - continue; - } - } - - if (cruft_cb) { - r = cruft_cb(de->d_name, path->buf, data); - if (r) - break; - } - } - closedir(dir); - - strbuf_setlen(path, baselen); - if (!r && subdir_cb) - r = subdir_cb(subdir_nr, path->buf, data); - - strbuf_setlen(path, origlen); - - return r; -} - -int for_each_loose_file_in_objdir_buf(struct strbuf *path, - each_loose_object_fn obj_cb, - each_loose_cruft_fn cruft_cb, - each_loose_subdir_fn subdir_cb, - void *data) -{ - int r = 0; - int i; - - for (i = 0; i < 256; i++) { - r = for_each_file_in_obj_subdir(i, path, obj_cb, cruft_cb, - subdir_cb, data); - if (r) - break; - } - - return r; -} - -int for_each_loose_file_in_objdir(const char *path, - each_loose_object_fn obj_cb, - each_loose_cruft_fn cruft_cb, - each_loose_subdir_fn subdir_cb, - void *data) -{ - struct strbuf buf = STRBUF_INIT; - int r; - - strbuf_addstr(&buf, path); - r = for_each_loose_file_in_objdir_buf(&buf, obj_cb, cruft_cb, - subdir_cb, data); - strbuf_release(&buf); - - return r; -} - -struct loose_alt_odb_data { - each_loose_object_fn *cb; - void *data; -}; - -static int loose_from_alt_odb(struct alternate_object_database *alt, - void *vdata) -{ - struct loose_alt_odb_data *data = vdata; - struct strbuf buf = STRBUF_INIT; - int r; - - strbuf_addstr(&buf, alt->path); - r = for_each_loose_file_in_objdir_buf(&buf, - data->cb, NULL, NULL, - data->data); - strbuf_release(&buf); - return r; -} - -int for_each_loose_object(each_loose_object_fn cb, void *data, unsigned flags) -{ - struct loose_alt_odb_data alt; - int r; - - r = for_each_loose_file_in_objdir(get_object_directory(), - cb, NULL, NULL, data); - if (r) - return r; - - if (flags & FOR_EACH_OBJECT_LOCAL_ONLY) - return 0; - - alt.cb = cb; - alt.data = data; - return foreach_alt_odb(loose_from_alt_odb, &alt); -} - -static int for_each_object_in_pack(struct packed_git *p, each_packed_object_fn cb, void *data) -{ - uint32_t i; - int r = 0; - - for (i = 0; i < p->num_objects; i++) { - struct object_id oid; - - if (!nth_packed_object_oid(&oid, p, i)) - return error("unable to get sha1 of object %u in %s", - i, p->pack_name); - - r = cb(&oid, p, i, data); - if (r) - break; - } - return r; -} - -int for_each_packed_object(each_packed_object_fn cb, void *data, unsigned flags) -{ - struct packed_git *p; - int r = 0; - int pack_errors = 0; - - prepare_packed_git(); - for (p = packed_git; p; p = p->next) { - if ((flags & FOR_EACH_OBJECT_LOCAL_ONLY) && !p->pack_local) - continue; - if (open_pack_index(p)) { - pack_errors = 1; - continue; - } - r = for_each_object_in_pack(p, cb, data); - if (r) - break; - } - return r ? r : pack_errors; -} - -static int check_stream_sha1(git_zstream *stream, - const char *hdr, - unsigned long size, - const char *path, - const unsigned char *expected_sha1) -{ - git_SHA_CTX c; - unsigned char real_sha1[GIT_MAX_RAWSZ]; - unsigned char buf[4096]; - unsigned long total_read; - int status = Z_OK; - - git_SHA1_Init(&c); - git_SHA1_Update(&c, hdr, stream->total_out); - - /* - * We already read some bytes into hdr, but the ones up to the NUL - * do not count against the object's content size. - */ - total_read = stream->total_out - strlen(hdr) - 1; - - /* - * This size comparison must be "<=" to read the final zlib packets; - * see the comment in unpack_sha1_rest for details. - */ - while (total_read <= size && - (status == Z_OK || status == Z_BUF_ERROR)) { - stream->next_out = buf; - stream->avail_out = sizeof(buf); - if (size - total_read < stream->avail_out) - stream->avail_out = size - total_read; - status = git_inflate(stream, Z_FINISH); - git_SHA1_Update(&c, buf, stream->next_out - buf); - total_read += stream->next_out - buf; - } - git_inflate_end(stream); - - if (status != Z_STREAM_END) { - error("corrupt loose object '%s'", sha1_to_hex(expected_sha1)); - return -1; - } - if (stream->avail_in) { - error("garbage at end of loose object '%s'", - sha1_to_hex(expected_sha1)); - return -1; - } - - git_SHA1_Final(real_sha1, &c); - if (hashcmp(expected_sha1, real_sha1)) { - error("sha1 mismatch for %s (expected %s)", path, - sha1_to_hex(expected_sha1)); - return -1; - } - - return 0; -} - -int read_loose_object(const char *path, - const unsigned char *expected_sha1, - enum object_type *type, - unsigned long *size, - void **contents) -{ - int ret = -1; - void *map = NULL; - unsigned long mapsize; - git_zstream stream; - char hdr[32]; - - *contents = NULL; - - map = map_sha1_file_1(path, NULL, &mapsize); - if (!map) { - error_errno("unable to mmap %s", path); - goto out; - } - - if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0) { - error("unable to unpack header of %s", path); - goto out; - } - - *type = parse_sha1_header(hdr, size); - if (*type < 0) { - error("unable to parse header of %s", path); - git_inflate_end(&stream); - goto out; - } - - if (*type == OBJ_BLOB) { - if (check_stream_sha1(&stream, hdr, *size, path, expected_sha1) < 0) - goto out; - } else { - *contents = unpack_sha1_rest(&stream, hdr, *size, expected_sha1); - if (!*contents) { - error("unable to unpack contents of %s", path); - git_inflate_end(&stream); - goto out; - } - if (check_sha1_signature(expected_sha1, *contents, - *size, typename(*type))) { - error("sha1 mismatch for %s (expected %s)", path, - sha1_to_hex(expected_sha1)); - free(*contents); - goto out; - } - } - - ret = 0; /* everything checks out */ - -out: - if (map) - munmap(map, mapsize); - return ret; -} |