/* * GIT - The information manager from hell * * Copyright (C) Linus Torvalds, 2005 * * This handles basic git object files - packing, unpacking, * creation etc. */ #include "cache.h" #include "abspath.h" #include "alloc.h" #include "config.h" #include "convert.h" #include "environment.h" #include "gettext.h" #include "hex.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 "hash-lookup.h" #include "bulk-checkin.h" #include "repository.h" #include "replace-object.h" #include "streaming.h" #include "dir.h" #include "list.h" #include "mergesort.h" #include "quote.h" #include "packfile.h" #include "object-store.h" #include "promisor-remote.h" #include "setup.h" #include "submodule.h" #include "fsck.h" #include "wrapper.h" /* The maximum size for an object header. */ #define MAX_HEADER_LEN 32 #define EMPTY_TREE_SHA1_BIN_LITERAL \ "\x4b\x82\x5d\xc6\x42\xcb\x6e\xb9\xa0\x60" \ "\xe5\x4b\xf8\xd6\x92\x88\xfb\xee\x49\x04" #define EMPTY_TREE_SHA256_BIN_LITERAL \ "\x6e\xf1\x9b\x41\x22\x5c\x53\x69\xf1\xc1" \ "\x04\xd4\x5d\x8d\x85\xef\xa9\xb0\x57\xb5" \ "\x3b\x14\xb4\xb9\xb9\x39\xdd\x74\xde\xcc" \ "\x53\x21" #define EMPTY_BLOB_SHA1_BIN_LITERAL \ "\xe6\x9d\xe2\x9b\xb2\xd1\xd6\x43\x4b\x8b" \ "\x29\xae\x77\x5a\xd8\xc2\xe4\x8c\x53\x91" #define EMPTY_BLOB_SHA256_BIN_LITERAL \ "\x47\x3a\x0f\x4c\x3b\xe8\xa9\x36\x81\xa2" \ "\x67\xe3\xb1\xe9\xa7\xdc\xda\x11\x85\x43" \ "\x6f\xe1\x41\xf7\x74\x91\x20\xa3\x03\x72" \ "\x18\x13" static const struct object_id empty_tree_oid = { .hash = EMPTY_TREE_SHA1_BIN_LITERAL, .algo = GIT_HASH_SHA1, }; static const struct object_id empty_blob_oid = { .hash = EMPTY_BLOB_SHA1_BIN_LITERAL, .algo = GIT_HASH_SHA1, }; static const struct object_id null_oid_sha1 = { .hash = {0}, .algo = GIT_HASH_SHA1, }; static const struct object_id empty_tree_oid_sha256 = { .hash = EMPTY_TREE_SHA256_BIN_LITERAL, .algo = GIT_HASH_SHA256, }; static const struct object_id empty_blob_oid_sha256 = { .hash = EMPTY_BLOB_SHA256_BIN_LITERAL, .algo = GIT_HASH_SHA256, }; static const struct object_id null_oid_sha256 = { .hash = {0}, .algo = GIT_HASH_SHA256, }; static void git_hash_sha1_init(git_hash_ctx *ctx) { git_SHA1_Init(&ctx->sha1); } static void git_hash_sha1_clone(git_hash_ctx *dst, const git_hash_ctx *src) { git_SHA1_Clone(&dst->sha1, &src->sha1); } static void git_hash_sha1_update(git_hash_ctx *ctx, const void *data, size_t len) { git_SHA1_Update(&ctx->sha1, data, len); } static void git_hash_sha1_final(unsigned char *hash, git_hash_ctx *ctx) { git_SHA1_Final(hash, &ctx->sha1); } static void git_hash_sha1_final_oid(struct object_id *oid, git_hash_ctx *ctx) { git_SHA1_Final(oid->hash, &ctx->sha1); memset(oid->hash + GIT_SHA1_RAWSZ, 0, GIT_MAX_RAWSZ - GIT_SHA1_RAWSZ); oid->algo = GIT_HASH_SHA1; } static void git_hash_sha256_init(git_hash_ctx *ctx) { git_SHA256_Init(&ctx->sha256); } static void git_hash_sha256_clone(git_hash_ctx *dst, const git_hash_ctx *src) { git_SHA256_Clone(&dst->sha256, &src->sha256); } static void git_hash_sha256_update(git_hash_ctx *ctx, const void *data, size_t len) { git_SHA256_Update(&ctx->sha256, data, len); } static void git_hash_sha256_final(unsigned char *hash, git_hash_ctx *ctx) { git_SHA256_Final(hash, &ctx->sha256); } static void git_hash_sha256_final_oid(struct object_id *oid, git_hash_ctx *ctx) { git_SHA256_Final(oid->hash, &ctx->sha256); /* * This currently does nothing, so the compiler should optimize it out, * but keep it in case we extend the hash size again. */ memset(oid->hash + GIT_SHA256_RAWSZ, 0, GIT_MAX_RAWSZ - GIT_SHA256_RAWSZ); oid->algo = GIT_HASH_SHA256; } static void git_hash_unknown_init(git_hash_ctx *ctx UNUSED) { BUG("trying to init unknown hash"); } static void git_hash_unknown_clone(git_hash_ctx *dst UNUSED, const git_hash_ctx *src UNUSED) { BUG("trying to clone unknown hash"); } static void git_hash_unknown_update(git_hash_ctx *ctx UNUSED, const void *data UNUSED, size_t len UNUSED) { BUG("trying to update unknown hash"); } static void git_hash_unknown_final(unsigned char *hash UNUSED, git_hash_ctx *ctx UNUSED) { BUG("trying to finalize unknown hash"); } static void git_hash_unknown_final_oid(struct object_id *oid UNUSED, git_hash_ctx *ctx UNUSED) { BUG("trying to finalize unknown hash"); } const struct git_hash_algo hash_algos[GIT_HASH_NALGOS] = { { .name = NULL, .format_id = 0x00000000, .rawsz = 0, .hexsz = 0, .blksz = 0, .init_fn = git_hash_unknown_init, .clone_fn = git_hash_unknown_clone, .update_fn = git_hash_unknown_update, .final_fn = git_hash_unknown_final, .final_oid_fn = git_hash_unknown_final_oid, .empty_tree = NULL, .empty_blob = NULL, .null_oid = NULL, }, { .name = "sha1", .format_id = GIT_SHA1_FORMAT_ID, .rawsz = GIT_SHA1_RAWSZ, .hexsz = GIT_SHA1_HEXSZ, .blksz = GIT_SHA1_BLKSZ, .init_fn = git_hash_sha1_init, .clone_fn = git_hash_sha1_clone, .update_fn = git_hash_sha1_update, .final_fn = git_hash_sha1_final, .final_oid_fn = git_hash_sha1_final_oid, .empty_tree = &empty_tree_oid, .empty_blob = &empty_blob_oid, .null_oid = &null_oid_sha1, }, { .name = "sha256", .format_id = GIT_SHA256_FORMAT_ID, .rawsz = GIT_SHA256_RAWSZ, .hexsz = GIT_SHA256_HEXSZ, .blksz = GIT_SHA256_BLKSZ, .init_fn = git_hash_sha256_init, .clone_fn = git_hash_sha256_clone, .update_fn = git_hash_sha256_update, .final_fn = git_hash_sha256_final, .final_oid_fn = git_hash_sha256_final_oid, .empty_tree = &empty_tree_oid_sha256, .empty_blob = &empty_blob_oid_sha256, .null_oid = &null_oid_sha256, } }; const struct object_id *null_oid(void) { return the_hash_algo->null_oid; } const char *empty_tree_oid_hex(void) { static char buf[GIT_MAX_HEXSZ + 1]; return oid_to_hex_r(buf, the_hash_algo->empty_tree); } const char *empty_blob_oid_hex(void) { static char buf[GIT_MAX_HEXSZ + 1]; return oid_to_hex_r(buf, the_hash_algo->empty_blob); } int hash_algo_by_name(const char *name) { int i; if (!name) return GIT_HASH_UNKNOWN; for (i = 1; i < GIT_HASH_NALGOS; i++) if (!strcmp(name, hash_algos[i].name)) return i; return GIT_HASH_UNKNOWN; } int hash_algo_by_id(uint32_t format_id) { int i; for (i = 1; i < GIT_HASH_NALGOS; i++) if (format_id == hash_algos[i].format_id) return i; return GIT_HASH_UNKNOWN; } int hash_algo_by_length(int len) { int i; for (i = 1; i < GIT_HASH_NALGOS; i++) if (len == hash_algos[i].rawsz) return i; return GIT_HASH_UNKNOWN; } /* * This is meant to hold a *small* number of objects that you would * want repo_read_object_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 { struct object_id oid; 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 = { .oid = { .hash = EMPTY_TREE_SHA1_BIN_LITERAL, }, .type = OBJ_TREE, .buf = "", }; static struct cached_object *find_cached_object(const struct object_id *oid) { int i; struct cached_object *co = cached_objects; for (i = 0; i < cached_object_nr; i++, co++) { if (oideq(&co->oid, oid)) return co; } if (oideq(oid, the_hash_algo->empty_tree)) return &empty_tree; return NULL; } static int get_conv_flags(unsigned flags) { if (flags & HASH_RENORMALIZE) return CONV_EOL_RENORMALIZE; else if (flags & HASH_WRITE_OBJECT) return global_conv_flags_eol | CONV_WRITE_OBJECT; else return 0; } 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); } static enum scld_error safe_create_leading_directories_1(char *path, int share) { 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 (share && adjust_shared_perm(path)) { ret = SCLD_PERMS; } *slash = slash_character; } return ret; } enum scld_error safe_create_leading_directories(char *path) { return safe_create_leading_directories_1(path, 1); } enum scld_error safe_create_leading_directories_no_share(char *path) { return safe_create_leading_directories_1(path, 0); } 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; } static void fill_loose_path(struct strbuf *buf, const struct object_id *oid) { int i; for (i = 0; i < the_hash_algo->rawsz; i++) { static char hex[] = "0123456789abcdef"; unsigned int val = oid->hash[i]; strbuf_addch(buf, hex[val >> 4]); strbuf_addch(buf, hex[val & 0xf]); if (!i) strbuf_addch(buf, '/'); } } static const char *odb_loose_path(struct object_directory *odb, struct strbuf *buf, const struct object_id *oid) { strbuf_reset(buf); strbuf_addstr(buf, odb->path); strbuf_addch(buf, '/'); fill_loose_path(buf, oid); return buf->buf; } const char *loose_object_path(struct repository *r, struct strbuf *buf, const struct object_id *oid) { return odb_loose_path(r->objects->odb, buf, oid); } /* * Return non-zero iff the path is usable as an alternate object database. */ static int alt_odb_usable(struct raw_object_store *o, struct strbuf *path, const char *normalized_objdir, khiter_t *pos) { int r; /* 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. */ if (!o->odb_by_path) { khiter_t p; o->odb_by_path = kh_init_odb_path_map(); assert(!o->odb->next); p = kh_put_odb_path_map(o->odb_by_path, o->odb->path, &r); assert(r == 1); /* never used */ kh_value(o->odb_by_path, p) = o->odb; } if (fspatheq(path->buf, normalized_objdir)) return 0; *pos = kh_put_odb_path_map(o->odb_by_path, path->buf, &r); /* r: 0 = exists, 1 = never used, 2 = deleted */ return r == 0 ? 0 : 1; } /* * Prepare alternate object database registry. * * The variable alt_odb_list points at the list of struct * object_directory. 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 all hex characters * of the object ID, an extra slash for the first level indirection, and * the terminating NUL. */ static void read_info_alternates(struct repository *r, const char *relative_base, int depth); static int link_alt_odb_entry(struct repository *r, const struct strbuf *entry, const char *relative_base, int depth, const char *normalized_objdir) { struct object_directory *ent; struct strbuf pathbuf = STRBUF_INIT; struct strbuf tmp = STRBUF_INIT; khiter_t pos; int ret = -1; if (!is_absolute_path(entry->buf) && relative_base) { strbuf_realpath(&pathbuf, relative_base, 1); strbuf_addch(&pathbuf, '/'); } strbuf_addbuf(&pathbuf, entry); if (!strbuf_realpath(&tmp, pathbuf.buf, 0)) { error(_("unable to normalize alternate object path: %s"), pathbuf.buf); goto error; } strbuf_swap(&pathbuf, &tmp); /* * 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(r->objects, &pathbuf, normalized_objdir, &pos)) goto error; CALLOC_ARRAY(ent, 1); /* pathbuf.buf is already in r->objects->odb_by_path */ ent->path = strbuf_detach(&pathbuf, NULL); /* add the alternate entry */ *r->objects->odb_tail = ent; r->objects->odb_tail = &(ent->next); ent->next = NULL; assert(r->objects->odb_by_path); kh_value(r->objects->odb_by_path, pos) = ent; /* recursively add alternates */ read_info_alternates(r, ent->path, depth + 1); ret = 0; error: strbuf_release(&tmp); strbuf_release(&pathbuf); return ret; } 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(struct repository *r, const char *alt, int sep, const char *relative_base, int depth) { struct strbuf objdirbuf = STRBUF_INIT; struct strbuf entry = STRBUF_INIT; if (!alt || !*alt) return; if (depth > 5) { error(_("%s: ignoring alternate object stores, nesting too deep"), relative_base); return; } strbuf_realpath(&objdirbuf, r->objects->odb->path, 1); while (*alt) { alt = parse_alt_odb_entry(alt, sep, &entry); if (!entry.len) continue; link_alt_odb_entry(r, &entry, relative_base, depth, objdirbuf.buf); } strbuf_release(&entry); strbuf_release(&objdirbuf); } static void read_info_alternates(struct repository *r, 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(r, buf.buf, '\n', relative_base, depth); strbuf_release(&buf); free(path); } void add_to_alternates_file(const char *reference) { struct lock_file lock = LOCK_INIT; char *alts = git_pathdup("objects/info/alternates"); FILE *in, *out; int found = 0; 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; 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); } else if (errno != ENOENT) die_errno(_("unable to read alternates file")); if (found) { rollback_lock_file(&lock); } else { fprintf_or_die(out, "%s\n", reference); if (commit_lock_file(&lock)) die_errno(_("unable to move new alternates file into place")); if (the_repository->objects->loaded_alternates) link_alt_odb_entries(the_repository, 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(the_repository); link_alt_odb_entries(the_repository, reference, '\n', NULL, 0); } struct object_directory *set_temporary_primary_odb(const char *dir, int will_destroy) { struct object_directory *new_odb; /* * Make sure alternates are initialized, or else our entry may be * overwritten when they are. */ prepare_alt_odb(the_repository); /* * Make a new primary odb and link the old primary ODB in as an * alternate */ new_odb = xcalloc(1, sizeof(*new_odb)); new_odb->path = xstrdup(dir); /* * Disable ref updates while a temporary odb is active, since * the objects in the database may roll back. */ new_odb->disable_ref_updates = 1; new_odb->will_destroy = will_destroy; new_odb->next = the_repository->objects->odb; the_repository->objects->odb = new_odb; return new_odb->next; } void restore_primary_odb(struct object_directory *restore_odb, const char *old_path) { struct object_directory *cur_odb = the_repository->objects->odb; if (strcmp(old_path, cur_odb->path)) BUG("expected %s as primary object store; found %s", old_path, cur_odb->path); if (cur_odb->next != restore_odb) BUG("we expect the old primary object store to be the first alternate"); the_repository->objects->odb = restore_odb; free_object_directory(cur_odb); } /* * 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 $GIT_DIR. * `err` must not be null. */ char *compute_alternate_path(const char *path, struct strbuf *err) { char *ref_git = NULL; const char *repo; int seen_error = 0; ref_git = real_pathdup(path, 0); if (!ref_git) { seen_error = 1; strbuf_addf(err, _("path '%s' does not exist"), path); goto out; } 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; } struct object_directory *find_odb(struct repository *r, const char *obj_dir) { struct object_directory *odb; char *obj_dir_real = real_pathdup(obj_dir, 1); struct strbuf odb_path_real = STRBUF_INIT; prepare_alt_odb(r); for (odb = r->objects->odb; odb; odb = odb->next) { strbuf_realpath(&odb_path_real, odb->path, 1); if (!strcmp(obj_dir_real, odb_path_real.buf)) break; } free(obj_dir_real); strbuf_release(&odb_path_real); if (!odb) die(_("could not find object directory matching %s"), obj_dir); return odb; } static void fill_alternate_refs_command(struct child_process *cmd, const char *repo_path) { const char *value; if (!git_config_get_value("core.alternateRefsCommand", &value)) { cmd->use_shell = 1; strvec_push(&cmd->args, value); strvec_push(&cmd->args, repo_path); } else { cmd->git_cmd = 1; strvec_pushf(&cmd->args, "--git-dir=%s", repo_path); strvec_push(&cmd->args, "for-each-ref"); strvec_push(&cmd->args, "--format=%(objectname)"); if (!git_config_get_value("core.alternateRefsPrefixes", &value)) { strvec_push(&cmd->args, "--"); strvec_split(&cmd->args, value); } } strvec_pushv(&cmd->env, (const char **)local_repo_env); cmd->out = -1; } static void read_alternate_refs(const char *path, alternate_ref_fn *cb, void *data) { struct child_process cmd = CHILD_PROCESS_INIT; struct strbuf line = STRBUF_INIT; FILE *fh; fill_alternate_refs_command(&cmd, path); if (start_command(&cmd)) return; fh = xfdopen(cmd.out, "r"); while (strbuf_getline_lf(&line, fh) != EOF) { struct object_id oid; const char *p; if (parse_oid_hex(line.buf, &oid, &p) || *p) { warning(_("invalid line while parsing alternate refs: %s"), line.buf); break; } cb(&oid, data); } fclose(fh); finish_command(&cmd); strbuf_release(&line); } struct alternate_refs_data { alternate_ref_fn *fn; void *data; }; static int refs_from_alternate_cb(struct object_directory *e, void *data) { struct strbuf path = STRBUF_INIT; size_t base_len; struct alternate_refs_data *cb = data; if (!strbuf_realpath(&path, e->path, 0)) goto out; if (!strbuf_strip_suffix(&path, "/objects")) goto out; base_len = path.len; /* Is this a git repository with refs? */ strbuf_addstr(&path, "/refs"); if (!is_directory(path.buf)) goto out; strbuf_setlen(&path, base_len); read_alternate_refs(path.buf, cb->fn, cb->data); out: strbuf_release(&path); return 0; } void for_each_alternate_ref(alternate_ref_fn fn, void *data) { struct alternate_refs_data cb; cb.fn = fn; cb.data = data; foreach_alt_odb(refs_from_alternate_cb, &cb); } int foreach_alt_odb(alt_odb_fn fn, void *cb) { struct object_directory *ent; int r = 0; prepare_alt_odb(the_repository); for (ent = the_repository->objects->odb->next; ent; ent = ent->next) { r = fn(ent, cb); if (r) break; } return r; } void prepare_alt_odb(struct repository *r) { if (r->objects->loaded_alternates) return; link_alt_odb_entries(r, r->objects->alternate_db, PATH_SEP, NULL, 0); read_info_alternates(r, r->objects->odb->path, 0); r->objects->loaded_alternates = 1; } /* Returns 1 if we have successfully freshened the file, 0 otherwise. */ static int freshen_file(const char *fn) { return !utime(fn, NULL); } /* * 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_odb(struct object_directory *odb, const struct object_id *oid, int freshen) { static struct strbuf path = STRBUF_INIT; odb_loose_path(odb, &path, oid); return check_and_freshen_file(path.buf, freshen); } static int check_and_freshen_local(const struct object_id *oid, int freshen) { return check_and_freshen_odb(the_repository->objects->odb, oid, freshen); } static int check_and_freshen_nonlocal(const struct object_id *oid, int freshen) { struct object_directory *odb; prepare_alt_odb(the_repository); for (odb = the_repository->objects->odb->next; odb; odb = odb->next) { if (check_and_freshen_odb(odb, oid, freshen)) return 1; } return 0; } static int check_and_freshen(const struct object_id *oid, int freshen) { return check_and_freshen_local(oid, freshen) || check_and_freshen_nonlocal(oid, freshen); } int has_loose_object_nonlocal(const struct object_id *oid) { return check_and_freshen_nonlocal(oid, 0); } int has_loose_object(const struct object_id *oid) { return check_and_freshen(oid, 0); } 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 && !length) ret = NULL; return ret; } const char *mmap_os_err(void) { static const char blank[] = ""; #if defined(__linux__) if (errno == ENOMEM) { /* this continues an existing error message: */ static const char enomem[] = ", check sys.vm.max_map_count and/or RLIMIT_DATA"; return enomem; } #endif /* OS-specific bits */ return blank; } 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%s"), mmap_os_err()); return ret; } static int format_object_header_literally(char *str, size_t size, const char *type, size_t objsize) { return xsnprintf(str, size, "%s %"PRIuMAX, type, (uintmax_t)objsize) + 1; } int format_object_header(char *str, size_t size, enum object_type type, size_t objsize) { const char *name = type_name(type); if (!name) BUG("could not get a type name for 'enum object_type' value %d", type); return format_object_header_literally(str, size, name, objsize); } int check_object_signature(struct repository *r, const struct object_id *oid, void *buf, unsigned long size, enum object_type type) { struct object_id real_oid; hash_object_file(r->hash_algo, buf, size, type, &real_oid); return !oideq(oid, &real_oid) ? -1 : 0; } int stream_object_signature(struct repository *r, const struct object_id *oid) { struct object_id real_oid; unsigned long size; enum object_type obj_type; struct git_istream *st; git_hash_ctx c; char hdr[MAX_HEADER_LEN]; int hdrlen; st = open_istream(r, oid, &obj_type, &size, NULL); if (!st) return -1; /* Generate the header */ hdrlen = format_object_header(hdr, sizeof(hdr), obj_type, size); /* Sha1.. */ r->hash_algo->init_fn(&c); r->hash_algo->update_fn(&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; r->hash_algo->update_fn(&c, buf, readlen); } r->hash_algo->final_oid_fn(&real_oid, &c); close_istream(st); return !oideq(oid, &real_oid) ? -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 "oid" 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 stat_loose_object(). */ static int stat_loose_object(struct repository *r, const struct object_id *oid, struct stat *st, const char **path) { struct object_directory *odb; static struct strbuf buf = STRBUF_INIT; prepare_alt_odb(r); for (odb = r->objects->odb; odb; odb = odb->next) { *path = odb_loose_path(odb, &buf, oid); if (!lstat(*path, st)) return 0; } return -1; } /* * Like stat_loose_object(), but actually open the object and return the * descriptor. See the caveats on the "path" parameter above. */ static int open_loose_object(struct repository *r, const struct object_id *oid, const char **path) { int fd; struct object_directory *odb; int most_interesting_errno = ENOENT; static struct strbuf buf = STRBUF_INIT; prepare_alt_odb(r); for (odb = r->objects->odb; odb; odb = odb->next) { *path = odb_loose_path(odb, &buf, oid); fd = git_open(*path); if (fd >= 0) return fd; if (most_interesting_errno == ENOENT) most_interesting_errno = errno; } errno = most_interesting_errno; return -1; } static int quick_has_loose(struct repository *r, const struct object_id *oid) { struct object_directory *odb; prepare_alt_odb(r); for (odb = r->objects->odb; odb; odb = odb->next) { if (oidtree_contains(odb_loose_cache(odb, oid), oid)) return 1; } return 0; } /* * Map and close the given loose object fd. The path argument is used for * error reporting. */ static void *map_fd(int fd, const char *path, unsigned long *size) { void *map = NULL; 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); close(fd); return NULL; } map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0); } close(fd); return map; } void *map_loose_object(struct repository *r, const struct object_id *oid, unsigned long *size) { const char *p; int fd = open_loose_object(r, oid, &p); if (fd < 0) return NULL; return map_fd(fd, p, size); } enum unpack_loose_header_result unpack_loose_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz, struct strbuf *header) { int status; /* 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); obj_read_unlock(); status = git_inflate(stream, 0); obj_read_lock(); if (status < Z_OK) return ULHR_BAD; /* * Check if entire header is unpacked in the first iteration. */ if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer)) return ULHR_OK; /* * We have a header longer than MAX_HEADER_LEN. The "header" * here is only non-NULL when we run "cat-file * --allow-unknown-type". */ if (!header) return ULHR_TOO_LONG; /* * 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 { obj_read_unlock(); status = git_inflate(stream, 0); obj_read_lock(); 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 ULHR_TOO_LONG; } static void *unpack_loose_rest(git_zstream *stream, void *buffer, unsigned long size, const struct object_id *oid) { 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) { obj_read_unlock(); status = git_inflate(stream, Z_FINISH); obj_read_lock(); } } if (status == Z_STREAM_END && !stream->avail_in) { git_inflate_end(stream); return buf; } if (status < 0) error(_("corrupt loose object '%s'"), oid_to_hex(oid)); else if (stream->avail_in) error(_("garbage at end of loose object '%s'"), oid_to_hex(oid)); 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. */ int parse_loose_header(const char *hdr, struct object_info *oi) { const char *type_buf = hdr; size_t 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->type_name) strbuf_add(oi->type_name, type_buf, type_len); 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 = st_add(st_mult(size, 10), c); } } if (oi->sizep) *oi->sizep = cast_size_t_to_ulong(size); /* * The length must be followed by a zero byte */ if (*hdr) return -1; /* * The format is valid, but the type may still be bogus. The * Caller needs to check its oi->typep. */ return 0; } static int loose_object_info(struct repository *r, const struct object_id *oid, struct object_info *oi, int flags) { int status = 0; int fd; unsigned long mapsize; const char *path; void *map; git_zstream stream; char hdr[MAX_HEADER_LEN]; struct strbuf hdrbuf = STRBUF_INIT; unsigned long size_scratch; enum object_type type_scratch; int allow_unknown = flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE; if (oi->delta_base_oid) oidclr(oi->delta_base_oid); /* * 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->type_name && !oi->sizep && !oi->contentp) { struct stat st; if (!oi->disk_sizep && (flags & OBJECT_INFO_QUICK)) return quick_has_loose(r, oid) ? 0 : -1; if (stat_loose_object(r, oid, &st, &path) < 0) return -1; if (oi->disk_sizep) *oi->disk_sizep = st.st_size; return 0; } fd = open_loose_object(r, oid, &path); if (fd < 0) { if (errno != ENOENT) error_errno(_("unable to open loose object %s"), oid_to_hex(oid)); return -1; } map = map_fd(fd, path, &mapsize); if (!map) return -1; if (!oi->sizep) oi->sizep = &size_scratch; if (!oi->typep) oi->typep = &type_scratch; if (oi->disk_sizep) *oi->disk_sizep = mapsize; switch (unpack_loose_header(&stream, map, mapsize, hdr, sizeof(hdr), allow_unknown ? &hdrbuf : NULL)) { case ULHR_OK: if (parse_loose_header(hdrbuf.len ? hdrbuf.buf : hdr, oi) < 0) status = error(_("unable to parse %s header"), oid_to_hex(oid)); else if (!allow_unknown && *oi->typep < 0) die(_("invalid object type")); if (!oi->contentp) break; *oi->contentp = unpack_loose_rest(&stream, hdr, *oi->sizep, oid); if (*oi->contentp) goto cleanup; status = -1; break; case ULHR_BAD: status = error(_("unable to unpack %s header"), oid_to_hex(oid)); break; case ULHR_TOO_LONG: status = error(_("header for %s too long, exceeds %d bytes"), oid_to_hex(oid), MAX_HEADER_LEN); break; } if (status && (flags & OBJECT_INFO_DIE_IF_CORRUPT)) die(_("loose object %s (stored in %s) is corrupt"), oid_to_hex(oid), path); git_inflate_end(&stream); cleanup: munmap(map, mapsize); if (oi->sizep == &size_scratch) oi->sizep = NULL; strbuf_release(&hdrbuf); if (oi->typep == &type_scratch) oi->typep = NULL; oi->whence = OI_LOOSE; return status; } int obj_read_use_lock = 0; pthread_mutex_t obj_read_mutex; void enable_obj_read_lock(void) { if (obj_read_use_lock) return; obj_read_use_lock = 1; init_recursive_mutex(&obj_read_mutex); } void disable_obj_read_lock(void) { if (!obj_read_use_lock) return; obj_read_use_lock = 0; pthread_mutex_destroy(&obj_read_mutex); } int fetch_if_missing = 1; static int do_oid_object_info_extended(struct repository *r, const struct object_id *oid, struct object_info *oi, unsigned flags) { static struct object_info blank_oi = OBJECT_INFO_INIT; struct cached_object *co; struct pack_entry e; int rtype; const struct object_id *real = oid; int already_retried = 0; if (flags & OBJECT_INFO_LOOKUP_REPLACE) real = lookup_replace_object(r, oid); if (is_null_oid(real)) return -1; if (!oi) oi = &blank_oi; 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_oid) oidclr(oi->delta_base_oid); if (oi->type_name) strbuf_addstr(oi->type_name, type_name(co->type)); if (oi->contentp) *oi->contentp = xmemdupz(co->buf, co->size); oi->whence = OI_CACHED; return 0; } while (1) { if (find_pack_entry(r, real, &e)) break; /* Most likely it's a loose object. */ if (!loose_object_info(r, real, oi, flags)) return 0; /* Not a loose object; someone else may have just packed it. */ if (!(flags & OBJECT_INFO_QUICK)) { reprepare_packed_git(r); if (find_pack_entry(r, real, &e)) break; } /* * If r is the_repository, this might be an attempt at * accessing a submodule object as if it were in the_repository * (having called add_submodule_odb() on that submodule's ODB). * If any such ODBs exist, register them and try again. */ if (r == the_repository && register_all_submodule_odb_as_alternates()) /* We added some alternates; retry */ continue; /* Check if it is a missing object */ if (fetch_if_missing && repo_has_promisor_remote(r) && !already_retried && !(flags & OBJECT_INFO_SKIP_FETCH_OBJECT)) { promisor_remote_get_direct(r, real, 1); already_retried = 1; continue; } if (flags & OBJECT_INFO_DIE_IF_CORRUPT) { const struct packed_git *p; if ((flags & OBJECT_INFO_LOOKUP_REPLACE) && !oideq(real, oid)) die(_("replacement %s not found for %s"), oid_to_hex(real), oid_to_hex(oid)); if ((p = has_packed_and_bad(r, real))) die(_("packed object %s (stored in %s) is corrupt"), oid_to_hex(real), p->pack_name); } 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(r, e.p, e.offset, oi); if (rtype < 0) { mark_bad_packed_object(e.p, real); return do_oid_object_info_extended(r, real, oi, 0); } else if (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; } int oid_object_info_extended(struct repository *r, const struct object_id *oid, struct object_info *oi, unsigned flags) { int ret; obj_read_lock(); ret = do_oid_object_info_extended(r, oid, oi, flags); obj_read_unlock(); return ret; } /* returns enum object_type or negative */ int oid_object_info(struct repository *r, const struct object_id *oid, unsigned long *sizep) { enum object_type type; struct object_info oi = OBJECT_INFO_INIT; oi.typep = &type; oi.sizep = sizep; if (oid_object_info_extended(r, oid, &oi, OBJECT_INFO_LOOKUP_REPLACE) < 0) return -1; return type; } int pretend_object_file(void *buf, unsigned long len, enum object_type type, struct object_id *oid) { struct cached_object *co; hash_object_file(the_hash_algo, buf, len, type, oid); if (repo_has_object_file_with_flags(the_repository, oid, OBJECT_INFO_QUICK | OBJECT_INFO_SKIP_FETCH_OBJECT) || find_cached_object(oid)) 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); oidcpy(&co->oid, oid); return 0; } /* * This function dies on corrupt objects; the callers who want to * deal with them should arrange to call oid_object_info_extended() and give * error messages themselves. */ void *repo_read_object_file(struct repository *r, const struct object_id *oid, enum object_type *type, unsigned long *size) { struct object_info oi = OBJECT_INFO_INIT; unsigned flags = OBJECT_INFO_DIE_IF_CORRUPT | OBJECT_INFO_LOOKUP_REPLACE; void *data; oi.typep = type; oi.sizep = size; oi.contentp = &data; if (oid_object_info_extended(r, oid, &oi, flags)) return NULL; return data; } void *read_object_with_reference(struct repository *r, const struct object_id *oid, enum object_type required_type, unsigned long *size, struct object_id *actual_oid_return) { enum object_type type; void *buffer; unsigned long isize; struct object_id actual_oid; oidcpy(&actual_oid, oid); while (1) { int ref_length = -1; const char *ref_type = NULL; buffer = repo_read_object_file(r, &actual_oid, &type, &isize); if (!buffer) return NULL; if (type == required_type) { *size = isize; if (actual_oid_return) oidcpy(actual_oid_return, &actual_oid); 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 + the_hash_algo->hexsz > isize || memcmp(buffer, ref_type, ref_length) || get_oid_hex((char *) buffer + ref_length, &actual_oid)) { free(buffer); return NULL; } free(buffer); /* Now we have the ID of the referred-to object in * actual_oid. Check again. */ } } static void hash_object_body(const struct git_hash_algo *algo, git_hash_ctx *c, const void *buf, unsigned long len, struct object_id *oid, char *hdr, int *hdrlen) { algo->init_fn(c); algo->update_fn(c, hdr, *hdrlen); algo->update_fn(c, buf, len); algo->final_oid_fn(oid, c); } static void write_object_file_prepare(const struct git_hash_algo *algo, const void *buf, unsigned long len, enum object_type type, struct object_id *oid, char *hdr, int *hdrlen) { git_hash_ctx c; /* Generate the header */ *hdrlen = format_object_header(hdr, *hdrlen, type, len); /* Sha1.. */ hash_object_body(algo, &c, buf, len, oid, hdr, hdrlen); } static void write_object_file_prepare_literally(const struct git_hash_algo *algo, const void *buf, unsigned long len, const char *type, struct object_id *oid, char *hdr, int *hdrlen) { git_hash_ctx c; *hdrlen = format_object_header_literally(hdr, *hdrlen, type, len); hash_object_body(algo, &c, buf, len, oid, hdr, hdrlen); } /* * 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 file %s"), filename); } /* FIXME!!! Collision check here ? */ } out: if (adjust_shared_perm(filename)) return error(_("unable to set permission to '%s'"), filename); return 0; } static void hash_object_file_literally(const struct git_hash_algo *algo, const void *buf, unsigned long len, const char *type, struct object_id *oid) { char hdr[MAX_HEADER_LEN]; int hdrlen = sizeof(hdr); write_object_file_prepare_literally(algo, buf, len, type, oid, hdr, &hdrlen); } void hash_object_file(const struct git_hash_algo *algo, const void *buf, unsigned long len, enum object_type type, struct object_id *oid) { hash_object_file_literally(algo, buf, len, type_name(type), oid); } /* Finalize a file on disk, and close it. */ static void close_loose_object(int fd, const char *filename) { if (the_repository->objects->odb->will_destroy) goto out; if (batch_fsync_enabled(FSYNC_COMPONENT_LOOSE_OBJECT)) fsync_loose_object_bulk_checkin(fd, filename); else if (fsync_object_files > 0) fsync_or_die(fd, filename); else fsync_component_or_die(FSYNC_COMPONENT_LOOSE_OBJECT, fd, filename); out: if (close(fd) != 0) die_errno(_("error when closing loose object 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; } /** * Common steps for loose object writers to start writing loose * objects: * * - Create tmpfile for the loose object. * - Setup zlib stream for compression. * - Start to feed header to zlib stream. * * Returns a "fd", which should later be provided to * end_loose_object_common(). */ static int start_loose_object_common(struct strbuf *tmp_file, const char *filename, unsigned flags, git_zstream *stream, unsigned char *buf, size_t buflen, git_hash_ctx *c, char *hdr, int hdrlen) { int fd; fd = create_tmpfile(tmp_file, filename); if (fd < 0) { if (flags & HASH_SILENT) return -1; else 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")); } /* Setup zlib stream for compression */ git_deflate_init(stream, zlib_compression_level); stream->next_out = buf; stream->avail_out = buflen; the_hash_algo->init_fn(c); /* Start to feed header to zlib stream */ stream->next_in = (unsigned char *)hdr; stream->avail_in = hdrlen; while (git_deflate(stream, 0) == Z_OK) ; /* nothing */ the_hash_algo->update_fn(c, hdr, hdrlen); return fd; } /** * Common steps for the inner git_deflate() loop for writing loose * objects. Returns what git_deflate() returns. */ static int write_loose_object_common(git_hash_ctx *c, git_zstream *stream, const int flush, unsigned char *in0, const int fd, unsigned char *compressed, const size_t compressed_len) { int ret; ret = git_deflate(stream, flush ? Z_FINISH : 0); the_hash_algo->update_fn(c, in0, stream->next_in - in0); if (write_in_full(fd, compressed, stream->next_out - compressed) < 0) die_errno(_("unable to write loose object file")); stream->next_out = compressed; stream->avail_out = compressed_len; return ret; } /** * Common steps for loose object writers to end writing loose objects: * * - End the compression of zlib stream. * - Get the calculated oid to "oid". */ static int end_loose_object_common(git_hash_ctx *c, git_zstream *stream, struct object_id *oid) { int ret; ret = git_deflate_end_gently(stream); if (ret != Z_OK) return ret; the_hash_algo->final_oid_fn(oid, c); return Z_OK; } static int write_loose_object(const struct object_id *oid, char *hdr, int hdrlen, const void *buf, unsigned long len, time_t mtime, unsigned flags) { int fd, ret; unsigned char compressed[4096]; git_zstream stream; git_hash_ctx c; struct object_id parano_oid; static struct strbuf tmp_file = STRBUF_INIT; static struct strbuf filename = STRBUF_INIT; if (batch_fsync_enabled(FSYNC_COMPONENT_LOOSE_OBJECT)) prepare_loose_object_bulk_checkin(); loose_object_path(the_repository, &filename, oid); fd = start_loose_object_common(&tmp_file, filename.buf, flags, &stream, compressed, sizeof(compressed), &c, hdr, hdrlen); if (fd < 0) return -1; /* Then the data itself.. */ stream.next_in = (void *)buf; stream.avail_in = len; do { unsigned char *in0 = stream.next_in; ret = write_loose_object_common(&c, &stream, 1, in0, fd, compressed, sizeof(compressed)); } while (ret == Z_OK); if (ret != Z_STREAM_END) die(_("unable to deflate new object %s (%d)"), oid_to_hex(oid), ret); ret = end_loose_object_common(&c, &stream, ¶no_oid); if (ret != Z_OK) die(_("deflateEnd on object %s failed (%d)"), oid_to_hex(oid), ret); if (!oideq(oid, ¶no_oid)) die(_("confused by unstable object source data for %s"), oid_to_hex(oid)); close_loose_object(fd, tmp_file.buf); if (mtime) { struct utimbuf utb; utb.actime = mtime; utb.modtime = mtime; if (utime(tmp_file.buf, &utb) < 0 && !(flags & HASH_SILENT)) warning_errno(_("failed utime() on %s"), tmp_file.buf); } return finalize_object_file(tmp_file.buf, filename.buf); } static int freshen_loose_object(const struct object_id *oid) { return check_and_freshen(oid, 1); } static int freshen_packed_object(const struct object_id *oid) { struct pack_entry e; if (!find_pack_entry(the_repository, oid, &e)) return 0; if (e.p->is_cruft) return 0; if (e.p->freshened) return 1; if (!freshen_file(e.p->pack_name)) return 0; e.p->freshened = 1; return 1; } int stream_loose_object(struct input_stream *in_stream, size_t len, struct object_id *oid) { int fd, ret, err = 0, flush = 0; unsigned char compressed[4096]; git_zstream stream; git_hash_ctx c; struct strbuf tmp_file = STRBUF_INIT; struct strbuf filename = STRBUF_INIT; int dirlen; char hdr[MAX_HEADER_LEN]; int hdrlen; if (batch_fsync_enabled(FSYNC_COMPONENT_LOOSE_OBJECT)) prepare_loose_object_bulk_checkin(); /* Since oid is not determined, save tmp file to odb path. */ strbuf_addf(&filename, "%s/", get_object_directory()); hdrlen = format_object_header(hdr, sizeof(hdr), OBJ_BLOB, len); /* * Common steps for write_loose_object and stream_loose_object to * start writing loose objects: * * - Create tmpfile for the loose object. * - Setup zlib stream for compression. * - Start to feed header to zlib stream. */ fd = start_loose_object_common(&tmp_file, filename.buf, 0, &stream, compressed, sizeof(compressed), &c, hdr, hdrlen); if (fd < 0) { err = -1; goto cleanup; } /* Then the data itself.. */ do { unsigned char *in0 = stream.next_in; if (!stream.avail_in && !in_stream->is_finished) { const void *in = in_stream->read(in_stream, &stream.avail_in); stream.next_in = (void *)in; in0 = (unsigned char *)in; /* All data has been read. */ if (in_stream->is_finished) flush = 1; } ret = write_loose_object_common(&c, &stream, flush, in0, fd, compressed, sizeof(compressed)); /* * Unlike write_loose_object(), we do not have the entire * buffer. If we get Z_BUF_ERROR due to too few input bytes, * then we'll replenish them in the next input_stream->read() * call when we loop. */ } while (ret == Z_OK || ret == Z_BUF_ERROR); if (stream.total_in != len + hdrlen) die(_("write stream object %ld != %"PRIuMAX), stream.total_in, (uintmax_t)len + hdrlen); /* * Common steps for write_loose_object and stream_loose_object to * end writing loose oject: * * - End the compression of zlib stream. * - Get the calculated oid. */ if (ret != Z_STREAM_END) die(_("unable to stream deflate new object (%d)"), ret); ret = end_loose_object_common(&c, &stream, oid); if (ret != Z_OK) die(_("deflateEnd on stream object failed (%d)"), ret); close_loose_object(fd, tmp_file.buf); if (freshen_packed_object(oid) || freshen_loose_object(oid)) { unlink_or_warn(tmp_file.buf); goto cleanup; } loose_object_path(the_repository, &filename, oid); /* We finally know the object path, and create the missing dir. */ dirlen = directory_size(filename.buf); if (dirlen) { struct strbuf dir = STRBUF_INIT; strbuf_add(&dir, filename.buf, dirlen); if (mkdir_in_gitdir(dir.buf) && errno != EEXIST) { err = error_errno(_("unable to create directory %s"), dir.buf); strbuf_release(&dir); goto cleanup; } strbuf_release(&dir); } err = finalize_object_file(tmp_file.buf, filename.buf); cleanup: strbuf_release(&tmp_file); strbuf_release(&filename); return err; } int write_object_file_flags(const void *buf, unsigned long len, enum object_type type, struct object_id *oid, unsigned flags) { char hdr[MAX_HEADER_LEN]; 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_object_file_prepare(the_hash_algo, buf, len, type, oid, hdr, &hdrlen); if (freshen_packed_object(oid) || freshen_loose_object(oid)) return 0; return write_loose_object(oid, hdr, hdrlen, buf, len, 0, flags); } int write_object_file_literally(const void *buf, unsigned long len, const char *type, struct object_id *oid, unsigned flags) { char *header; int hdrlen, status = 0; /* type string, SP, %lu of the length plus NUL must fit this */ hdrlen = strlen(type) + MAX_HEADER_LEN; header = xmalloc(hdrlen); write_object_file_prepare_literally(the_hash_algo, buf, len, type, oid, header, &hdrlen); if (!(flags & HASH_WRITE_OBJECT)) goto cleanup; if (freshen_packed_object(oid) || freshen_loose_object(oid)) goto cleanup; status = write_loose_object(oid, header, hdrlen, buf, len, 0, 0); cleanup: free(header); return status; } int force_object_loose(const struct object_id *oid, time_t mtime) { void *buf; unsigned long len; struct object_info oi = OBJECT_INFO_INIT; enum object_type type; char hdr[MAX_HEADER_LEN]; int hdrlen; int ret; if (has_loose_object(oid)) return 0; oi.typep = &type; oi.sizep = &len; oi.contentp = &buf; if (oid_object_info_extended(the_repository, oid, &oi, 0)) return error(_("cannot read object for %s"), oid_to_hex(oid)); hdrlen = format_object_header(hdr, sizeof(hdr), type, len); ret = write_loose_object(oid, hdr, hdrlen, buf, len, mtime, 0); free(buf); return ret; } int has_object(struct repository *r, const struct object_id *oid, unsigned flags) { int quick = !(flags & HAS_OBJECT_RECHECK_PACKED); unsigned object_info_flags = OBJECT_INFO_SKIP_FETCH_OBJECT | (quick ? OBJECT_INFO_QUICK : 0); if (!startup_info->have_repository) return 0; return oid_object_info_extended(r, oid, NULL, object_info_flags) >= 0; } int repo_has_object_file_with_flags(struct repository *r, const struct object_id *oid, int flags) { if (!startup_info->have_repository) return 0; return oid_object_info_extended(r, oid, NULL, flags) >= 0; } int repo_has_object_file(struct repository *r, const struct object_id *oid) { return repo_has_object_file_with_flags(r, oid, 0); } /* * We can't use the normal fsck_error_function() for index_mem(), * because we don't yet have a valid oid for it to report. Instead, * report the minimal fsck error here, and rely on the caller to * give more context. */ static int hash_format_check_report(struct fsck_options *opts, const struct object_id *oid, enum object_type object_type, enum fsck_msg_type msg_type, enum fsck_msg_id msg_id, const char *message) { error(_("object fails fsck: %s"), message); return 1; } static int index_mem(struct index_state *istate, struct object_id *oid, void *buf, size_t size, enum object_type type, const char *path, unsigned flags) { int ret = 0; int 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(istate, path, buf, size, &nbuf, get_conv_flags(flags))) { buf = strbuf_detach(&nbuf, &size); re_allocated = 1; } } if (flags & HASH_FORMAT_CHECK) { struct fsck_options opts = FSCK_OPTIONS_DEFAULT; opts.strict = 1; opts.error_func = hash_format_check_report; if (fsck_buffer(null_oid(), type, buf, size, &opts)) die(_("refusing to create malformed object")); fsck_finish(&opts); } if (write_object) ret = write_object_file(buf, size, type, oid); else hash_object_file(the_hash_algo, buf, size, type, oid); if (re_allocated) free(buf); return ret; } static int index_stream_convert_blob(struct index_state *istate, struct object_id *oid, int fd, const char *path, unsigned flags) { int ret = 0; const int write_object = flags & HASH_WRITE_OBJECT; struct strbuf sbuf = STRBUF_INIT; assert(path); assert(would_convert_to_git_filter_fd(istate, path)); convert_to_git_filter_fd(istate, path, fd, &sbuf, get_conv_flags(flags)); if (write_object) ret = write_object_file(sbuf.buf, sbuf.len, OBJ_BLOB, oid); else hash_object_file(the_hash_algo, sbuf.buf, sbuf.len, OBJ_BLOB, oid); strbuf_release(&sbuf); return ret; } static int index_pipe(struct index_state *istate, struct object_id *oid, 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(istate, oid, 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(struct index_state *istate, struct object_id *oid, int fd, size_t size, enum object_type type, const char *path, unsigned flags) { int ret; if (!size) { ret = index_mem(istate, oid, "", size, type, path, flags); } else if (size <= SMALL_FILE_SIZE) { char *buf = xmalloc(size); ssize_t read_result = read_in_full(fd, buf, size); if (read_result < 0) ret = error_errno(_("read error while indexing %s"), path ? path : ""); else if (read_result != size) ret = error(_("short read while indexing %s"), path ? path : ""); else ret = index_mem(istate, oid, buf, size, type, path, flags); free(buf); } else { void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0); ret = index_mem(istate, oid, 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(struct object_id *oid, int fd, size_t size, enum object_type type, const char *path, unsigned flags) { return index_bulk_checkin(oid, fd, size, type, path, flags); } int index_fd(struct index_state *istate, struct object_id *oid, 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(istate, path)) ret = index_stream_convert_blob(istate, oid, fd, path, flags); else if (!S_ISREG(st->st_mode)) ret = index_pipe(istate, oid, fd, type, path, flags); else if (st->st_size <= big_file_threshold || type != OBJ_BLOB || (path && would_convert_to_git(istate, path))) ret = index_core(istate, oid, fd, xsize_t(st->st_size), type, path, flags); else ret = index_stream(oid, fd, xsize_t(st->st_size), type, path, flags); close(fd); return ret; } int index_path(struct index_state *istate, struct object_id *oid, const char *path, struct stat *st, unsigned flags) { int fd; struct strbuf sb = STRBUF_INIT; int rc = 0; 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(istate, oid, 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_object_file(the_hash_algo, sb.buf, sb.len, OBJ_BLOB, oid); else if (write_object_file(sb.buf, sb.len, OBJ_BLOB, oid)) rc = error(_("%s: failed to insert into database"), path); strbuf_release(&sb); break; case S_IFDIR: return resolve_gitlink_ref(path, "HEAD", oid); default: return error(_("%s: unsupported file type"), path); } return rc; } 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_oid_type(const struct object_id *oid, enum object_type expect) { enum object_type type = oid_object_info(the_repository, oid, NULL); if (type < 0) die(_("%s is not a valid object"), oid_to_hex(oid)); if (type != expect) die(_("%s is not a valid '%s' object"), oid_to_hex(oid), type_name(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; struct object_id oid; if (subdir_nr > 0xff) BUG("invalid loose object subdirectory: %x", subdir_nr); origlen = path->len; strbuf_complete(path, '/'); strbuf_addf(path, "%02x", subdir_nr); dir = opendir(path->buf); if (!dir) { if (errno != ENOENT) r = error_errno(_("unable to open %s"), path->buf); strbuf_setlen(path, origlen); return r; } oid.hash[0] = subdir_nr; strbuf_addch(path, '/'); baselen = path->len; while ((de = readdir_skip_dot_and_dotdot(dir))) { size_t namelen; namelen = strlen(de->d_name); strbuf_setlen(path, baselen); strbuf_add(path, de->d_name, namelen); if (namelen == the_hash_algo->hexsz - 2 && !hex_to_bytes(oid.hash + 1, de->d_name, the_hash_algo->rawsz - 1)) { oid_set_algo(&oid, the_hash_algo); 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 - 1); 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; } int for_each_loose_object(each_loose_object_fn cb, void *data, enum for_each_object_flags flags) { struct object_directory *odb; prepare_alt_odb(the_repository); for (odb = the_repository->objects->odb; odb; odb = odb->next) { int r = for_each_loose_file_in_objdir(odb->path, cb, NULL, NULL, data); if (r) return r; if (flags & FOR_EACH_OBJECT_LOCAL_ONLY) break; } return 0; } static int append_loose_object(const struct object_id *oid, const char *path UNUSED, void *data) { oidtree_insert(data, oid); return 0; } struct oidtree *odb_loose_cache(struct object_directory *odb, const struct object_id *oid) { int subdir_nr = oid->hash[0]; struct strbuf buf = STRBUF_INIT; size_t word_bits = bitsizeof(odb->loose_objects_subdir_seen[0]); size_t word_index = subdir_nr / word_bits; size_t mask = (size_t)1u << (subdir_nr % word_bits); uint32_t *bitmap; if (subdir_nr < 0 || subdir_nr >= bitsizeof(odb->loose_objects_subdir_seen)) BUG("subdir_nr out of range"); bitmap = &odb->loose_objects_subdir_seen[word_index]; if (*bitmap & mask) return odb->loose_objects_cache; if (!odb->loose_objects_cache) { ALLOC_ARRAY(odb->loose_objects_cache, 1); oidtree_init(odb->loose_objects_cache); } strbuf_addstr(&buf, odb->path); for_each_file_in_obj_subdir(subdir_nr, &buf, append_loose_object, NULL, NULL, odb->loose_objects_cache); *bitmap |= mask; strbuf_release(&buf); return odb->loose_objects_cache; } void odb_clear_loose_cache(struct object_directory *odb) { oidtree_clear(odb->loose_objects_cache); FREE_AND_NULL(odb->loose_objects_cache); memset(&odb->loose_objects_subdir_seen, 0, sizeof(odb->loose_objects_subdir_seen)); } static int check_stream_oid(git_zstream *stream, const char *hdr, unsigned long size, const char *path, const struct object_id *expected_oid) { git_hash_ctx c; struct object_id real_oid; unsigned char buf[4096]; unsigned long total_read; int status = Z_OK; the_hash_algo->init_fn(&c); the_hash_algo->update_fn(&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_loose_rest for details. */ while (total_read <= size && (status == Z_OK || (status == Z_BUF_ERROR && !stream->avail_out))) { 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); the_hash_algo->update_fn(&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'"), oid_to_hex(expected_oid)); return -1; } if (stream->avail_in) { error(_("garbage at end of loose object '%s'"), oid_to_hex(expected_oid)); return -1; } the_hash_algo->final_oid_fn(&real_oid, &c); if (!oideq(expected_oid, &real_oid)) { error(_("hash mismatch for %s (expected %s)"), path, oid_to_hex(expected_oid)); return -1; } return 0; } int read_loose_object(const char *path, const struct object_id *expected_oid, struct object_id *real_oid, void **contents, struct object_info *oi) { int ret = -1; int fd; void *map = NULL; unsigned long mapsize; git_zstream stream; char hdr[MAX_HEADER_LEN]; unsigned long *size = oi->sizep; fd = git_open(path); if (fd >= 0) map = map_fd(fd, path, &mapsize); if (!map) { error_errno(_("unable to mmap %s"), path); goto out; } if (unpack_loose_header(&stream, map, mapsize, hdr, sizeof(hdr), NULL) != ULHR_OK) { error(_("unable to unpack header of %s"), path); goto out; } if (parse_loose_header(hdr, oi) < 0) { error(_("unable to parse header of %s"), path); git_inflate_end(&stream); goto out; } if (*oi->typep == OBJ_BLOB && *size > big_file_threshold) { if (check_stream_oid(&stream, hdr, *size, path, expected_oid) < 0) goto out; } else { *contents = unpack_loose_rest(&stream, hdr, *size, expected_oid); if (!*contents) { error(_("unable to unpack contents of %s"), path); git_inflate_end(&stream); goto out; } hash_object_file_literally(the_repository->hash_algo, *contents, *size, oi->type_name->buf, real_oid); if (!oideq(expected_oid, real_oid)) goto out; } ret = 0; /* everything checks out */ out: if (map) munmap(map, mapsize); return ret; }