Merge branch 'es/doc-worktree-guessremote-config'
[git.git] / sha1-file.c
blob5a272f70de149a2102a1db8f1b3165f3f20da935
1 /*
2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
6 * This handles basic git sha1 object files - packing, unpacking,
7 * creation etc.
8 */
9 #include "cache.h"
10 #include "config.h"
11 #include "string-list.h"
12 #include "lockfile.h"
13 #include "delta.h"
14 #include "pack.h"
15 #include "blob.h"
16 #include "commit.h"
17 #include "run-command.h"
18 #include "tag.h"
19 #include "tree.h"
20 #include "tree-walk.h"
21 #include "refs.h"
22 #include "pack-revindex.h"
23 #include "sha1-lookup.h"
24 #include "bulk-checkin.h"
25 #include "repository.h"
26 #include "replace-object.h"
27 #include "streaming.h"
28 #include "dir.h"
29 #include "list.h"
30 #include "mergesort.h"
31 #include "quote.h"
32 #include "packfile.h"
33 #include "fetch-object.h"
34 #include "object-store.h"
36 /* The maximum size for an object header. */
37 #define MAX_HEADER_LEN 32
40 #define EMPTY_TREE_SHA1_BIN_LITERAL \
41 "\x4b\x82\x5d\xc6\x42\xcb\x6e\xb9\xa0\x60" \
42 "\xe5\x4b\xf8\xd6\x92\x88\xfb\xee\x49\x04"
44 #define EMPTY_BLOB_SHA1_BIN_LITERAL \
45 "\xe6\x9d\xe2\x9b\xb2\xd1\xd6\x43\x4b\x8b" \
46 "\x29\xae\x77\x5a\xd8\xc2\xe4\x8c\x53\x91"
48 const unsigned char null_sha1[GIT_MAX_RAWSZ];
49 const struct object_id null_oid;
50 static const struct object_id empty_tree_oid = {
51 EMPTY_TREE_SHA1_BIN_LITERAL
53 static const struct object_id empty_blob_oid = {
54 EMPTY_BLOB_SHA1_BIN_LITERAL
57 static void git_hash_sha1_init(git_hash_ctx *ctx)
59 git_SHA1_Init(&ctx->sha1);
62 static void git_hash_sha1_update(git_hash_ctx *ctx, const void *data, size_t len)
64 git_SHA1_Update(&ctx->sha1, data, len);
67 static void git_hash_sha1_final(unsigned char *hash, git_hash_ctx *ctx)
69 git_SHA1_Final(hash, &ctx->sha1);
72 static void git_hash_unknown_init(git_hash_ctx *ctx)
74 BUG("trying to init unknown hash");
77 static void git_hash_unknown_update(git_hash_ctx *ctx, const void *data, size_t len)
79 BUG("trying to update unknown hash");
82 static void git_hash_unknown_final(unsigned char *hash, git_hash_ctx *ctx)
84 BUG("trying to finalize unknown hash");
87 const struct git_hash_algo hash_algos[GIT_HASH_NALGOS] = {
89 NULL,
90 0x00000000,
93 git_hash_unknown_init,
94 git_hash_unknown_update,
95 git_hash_unknown_final,
96 NULL,
97 NULL,
100 "sha-1",
101 /* "sha1", big-endian */
102 0x73686131,
103 GIT_SHA1_RAWSZ,
104 GIT_SHA1_HEXSZ,
105 git_hash_sha1_init,
106 git_hash_sha1_update,
107 git_hash_sha1_final,
108 &empty_tree_oid,
109 &empty_blob_oid,
113 const char *empty_tree_oid_hex(void)
115 static char buf[GIT_MAX_HEXSZ + 1];
116 return oid_to_hex_r(buf, the_hash_algo->empty_tree);
119 const char *empty_blob_oid_hex(void)
121 static char buf[GIT_MAX_HEXSZ + 1];
122 return oid_to_hex_r(buf, the_hash_algo->empty_blob);
126 * This is meant to hold a *small* number of objects that you would
127 * want read_sha1_file() to be able to return, but yet you do not want
128 * to write them into the object store (e.g. a browse-only
129 * application).
131 static struct cached_object {
132 struct object_id oid;
133 enum object_type type;
134 void *buf;
135 unsigned long size;
136 } *cached_objects;
137 static int cached_object_nr, cached_object_alloc;
139 static struct cached_object empty_tree = {
140 { EMPTY_TREE_SHA1_BIN_LITERAL },
141 OBJ_TREE,
146 static struct cached_object *find_cached_object(const struct object_id *oid)
148 int i;
149 struct cached_object *co = cached_objects;
151 for (i = 0; i < cached_object_nr; i++, co++) {
152 if (oideq(&co->oid, oid))
153 return co;
155 if (oideq(oid, the_hash_algo->empty_tree))
156 return &empty_tree;
157 return NULL;
161 static int get_conv_flags(unsigned flags)
163 if (flags & HASH_RENORMALIZE)
164 return CONV_EOL_RENORMALIZE;
165 else if (flags & HASH_WRITE_OBJECT)
166 return global_conv_flags_eol | CONV_WRITE_OBJECT;
167 else
168 return 0;
172 int mkdir_in_gitdir(const char *path)
174 if (mkdir(path, 0777)) {
175 int saved_errno = errno;
176 struct stat st;
177 struct strbuf sb = STRBUF_INIT;
179 if (errno != EEXIST)
180 return -1;
182 * Are we looking at a path in a symlinked worktree
183 * whose original repository does not yet have it?
184 * e.g. .git/rr-cache pointing at its original
185 * repository in which the user hasn't performed any
186 * conflict resolution yet?
188 if (lstat(path, &st) || !S_ISLNK(st.st_mode) ||
189 strbuf_readlink(&sb, path, st.st_size) ||
190 !is_absolute_path(sb.buf) ||
191 mkdir(sb.buf, 0777)) {
192 strbuf_release(&sb);
193 errno = saved_errno;
194 return -1;
196 strbuf_release(&sb);
198 return adjust_shared_perm(path);
201 enum scld_error safe_create_leading_directories(char *path)
203 char *next_component = path + offset_1st_component(path);
204 enum scld_error ret = SCLD_OK;
206 while (ret == SCLD_OK && next_component) {
207 struct stat st;
208 char *slash = next_component, slash_character;
210 while (*slash && !is_dir_sep(*slash))
211 slash++;
213 if (!*slash)
214 break;
216 next_component = slash + 1;
217 while (is_dir_sep(*next_component))
218 next_component++;
219 if (!*next_component)
220 break;
222 slash_character = *slash;
223 *slash = '\0';
224 if (!stat(path, &st)) {
225 /* path exists */
226 if (!S_ISDIR(st.st_mode)) {
227 errno = ENOTDIR;
228 ret = SCLD_EXISTS;
230 } else if (mkdir(path, 0777)) {
231 if (errno == EEXIST &&
232 !stat(path, &st) && S_ISDIR(st.st_mode))
233 ; /* somebody created it since we checked */
234 else if (errno == ENOENT)
236 * Either mkdir() failed because
237 * somebody just pruned the containing
238 * directory, or stat() failed because
239 * the file that was in our way was
240 * just removed. Either way, inform
241 * the caller that it might be worth
242 * trying again:
244 ret = SCLD_VANISHED;
245 else
246 ret = SCLD_FAILED;
247 } else if (adjust_shared_perm(path)) {
248 ret = SCLD_PERMS;
250 *slash = slash_character;
252 return ret;
255 enum scld_error safe_create_leading_directories_const(const char *path)
257 int save_errno;
258 /* path points to cache entries, so xstrdup before messing with it */
259 char *buf = xstrdup(path);
260 enum scld_error result = safe_create_leading_directories(buf);
262 save_errno = errno;
263 free(buf);
264 errno = save_errno;
265 return result;
268 int raceproof_create_file(const char *path, create_file_fn fn, void *cb)
271 * The number of times we will try to remove empty directories
272 * in the way of path. This is only 1 because if another
273 * process is racily creating directories that conflict with
274 * us, we don't want to fight against them.
276 int remove_directories_remaining = 1;
279 * The number of times that we will try to create the
280 * directories containing path. We are willing to attempt this
281 * more than once, because another process could be trying to
282 * clean up empty directories at the same time as we are
283 * trying to create them.
285 int create_directories_remaining = 3;
287 /* A scratch copy of path, filled lazily if we need it: */
288 struct strbuf path_copy = STRBUF_INIT;
290 int ret, save_errno;
292 /* Sanity check: */
293 assert(*path);
295 retry_fn:
296 ret = fn(path, cb);
297 save_errno = errno;
298 if (!ret)
299 goto out;
301 if (errno == EISDIR && remove_directories_remaining-- > 0) {
303 * A directory is in the way. Maybe it is empty; try
304 * to remove it:
306 if (!path_copy.len)
307 strbuf_addstr(&path_copy, path);
309 if (!remove_dir_recursively(&path_copy, REMOVE_DIR_EMPTY_ONLY))
310 goto retry_fn;
311 } else if (errno == ENOENT && create_directories_remaining-- > 0) {
313 * Maybe the containing directory didn't exist, or
314 * maybe it was just deleted by a process that is
315 * racing with us to clean up empty directories. Try
316 * to create it:
318 enum scld_error scld_result;
320 if (!path_copy.len)
321 strbuf_addstr(&path_copy, path);
323 do {
324 scld_result = safe_create_leading_directories(path_copy.buf);
325 if (scld_result == SCLD_OK)
326 goto retry_fn;
327 } while (scld_result == SCLD_VANISHED && create_directories_remaining-- > 0);
330 out:
331 strbuf_release(&path_copy);
332 errno = save_errno;
333 return ret;
336 static void fill_sha1_path(struct strbuf *buf, const unsigned char *sha1)
338 int i;
339 for (i = 0; i < the_hash_algo->rawsz; i++) {
340 static char hex[] = "0123456789abcdef";
341 unsigned int val = sha1[i];
342 strbuf_addch(buf, hex[val >> 4]);
343 strbuf_addch(buf, hex[val & 0xf]);
344 if (!i)
345 strbuf_addch(buf, '/');
349 static const char *odb_loose_path(struct object_directory *odb,
350 struct strbuf *buf,
351 const unsigned char *sha1)
353 strbuf_reset(buf);
354 strbuf_addstr(buf, odb->path);
355 strbuf_addch(buf, '/');
356 fill_sha1_path(buf, sha1);
357 return buf->buf;
360 const char *loose_object_path(struct repository *r, struct strbuf *buf,
361 const unsigned char *sha1)
363 return odb_loose_path(r->objects->odb, buf, sha1);
367 * Return non-zero iff the path is usable as an alternate object database.
369 static int alt_odb_usable(struct raw_object_store *o,
370 struct strbuf *path,
371 const char *normalized_objdir)
373 struct object_directory *odb;
375 /* Detect cases where alternate disappeared */
376 if (!is_directory(path->buf)) {
377 error(_("object directory %s does not exist; "
378 "check .git/objects/info/alternates"),
379 path->buf);
380 return 0;
384 * Prevent the common mistake of listing the same
385 * thing twice, or object directory itself.
387 for (odb = o->odb; odb; odb = odb->next) {
388 if (!fspathcmp(path->buf, odb->path))
389 return 0;
391 if (!fspathcmp(path->buf, normalized_objdir))
392 return 0;
394 return 1;
398 * Prepare alternate object database registry.
400 * The variable alt_odb_list points at the list of struct
401 * object_directory. The elements on this list come from
402 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
403 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
404 * whose contents is similar to that environment variable but can be
405 * LF separated. Its base points at a statically allocated buffer that
406 * contains "/the/directory/corresponding/to/.git/objects/...", while
407 * its name points just after the slash at the end of ".git/objects/"
408 * in the example above, and has enough space to hold 40-byte hex
409 * SHA1, an extra slash for the first level indirection, and the
410 * terminating NUL.
412 static void read_info_alternates(struct repository *r,
413 const char *relative_base,
414 int depth);
415 static int link_alt_odb_entry(struct repository *r, const char *entry,
416 const char *relative_base, int depth, const char *normalized_objdir)
418 struct object_directory *ent;
419 struct strbuf pathbuf = STRBUF_INIT;
421 if (!is_absolute_path(entry) && relative_base) {
422 strbuf_realpath(&pathbuf, relative_base, 1);
423 strbuf_addch(&pathbuf, '/');
425 strbuf_addstr(&pathbuf, entry);
427 if (strbuf_normalize_path(&pathbuf) < 0 && relative_base) {
428 error(_("unable to normalize alternate object path: %s"),
429 pathbuf.buf);
430 strbuf_release(&pathbuf);
431 return -1;
435 * The trailing slash after the directory name is given by
436 * this function at the end. Remove duplicates.
438 while (pathbuf.len && pathbuf.buf[pathbuf.len - 1] == '/')
439 strbuf_setlen(&pathbuf, pathbuf.len - 1);
441 if (!alt_odb_usable(r->objects, &pathbuf, normalized_objdir)) {
442 strbuf_release(&pathbuf);
443 return -1;
446 ent = xcalloc(1, sizeof(*ent));
447 ent->path = xstrdup(pathbuf.buf);
449 /* add the alternate entry */
450 *r->objects->odb_tail = ent;
451 r->objects->odb_tail = &(ent->next);
452 ent->next = NULL;
454 /* recursively add alternates */
455 read_info_alternates(r, pathbuf.buf, depth + 1);
457 strbuf_release(&pathbuf);
458 return 0;
461 static const char *parse_alt_odb_entry(const char *string,
462 int sep,
463 struct strbuf *out)
465 const char *end;
467 strbuf_reset(out);
469 if (*string == '#') {
470 /* comment; consume up to next separator */
471 end = strchrnul(string, sep);
472 } else if (*string == '"' && !unquote_c_style(out, string, &end)) {
474 * quoted path; unquote_c_style has copied the
475 * data for us and set "end". Broken quoting (e.g.,
476 * an entry that doesn't end with a quote) falls
477 * back to the unquoted case below.
479 } else {
480 /* normal, unquoted path */
481 end = strchrnul(string, sep);
482 strbuf_add(out, string, end - string);
485 if (*end)
486 end++;
487 return end;
490 static void link_alt_odb_entries(struct repository *r, const char *alt,
491 int sep, const char *relative_base, int depth)
493 struct strbuf objdirbuf = STRBUF_INIT;
494 struct strbuf entry = STRBUF_INIT;
496 if (!alt || !*alt)
497 return;
499 if (depth > 5) {
500 error(_("%s: ignoring alternate object stores, nesting too deep"),
501 relative_base);
502 return;
505 strbuf_add_absolute_path(&objdirbuf, r->objects->odb->path);
506 if (strbuf_normalize_path(&objdirbuf) < 0)
507 die(_("unable to normalize object directory: %s"),
508 objdirbuf.buf);
510 while (*alt) {
511 alt = parse_alt_odb_entry(alt, sep, &entry);
512 if (!entry.len)
513 continue;
514 link_alt_odb_entry(r, entry.buf,
515 relative_base, depth, objdirbuf.buf);
517 strbuf_release(&entry);
518 strbuf_release(&objdirbuf);
521 static void read_info_alternates(struct repository *r,
522 const char *relative_base,
523 int depth)
525 char *path;
526 struct strbuf buf = STRBUF_INIT;
528 path = xstrfmt("%s/info/alternates", relative_base);
529 if (strbuf_read_file(&buf, path, 1024) < 0) {
530 warn_on_fopen_errors(path);
531 free(path);
532 return;
535 link_alt_odb_entries(r, buf.buf, '\n', relative_base, depth);
536 strbuf_release(&buf);
537 free(path);
540 void add_to_alternates_file(const char *reference)
542 struct lock_file lock = LOCK_INIT;
543 char *alts = git_pathdup("objects/info/alternates");
544 FILE *in, *out;
545 int found = 0;
547 hold_lock_file_for_update(&lock, alts, LOCK_DIE_ON_ERROR);
548 out = fdopen_lock_file(&lock, "w");
549 if (!out)
550 die_errno(_("unable to fdopen alternates lockfile"));
552 in = fopen(alts, "r");
553 if (in) {
554 struct strbuf line = STRBUF_INIT;
556 while (strbuf_getline(&line, in) != EOF) {
557 if (!strcmp(reference, line.buf)) {
558 found = 1;
559 break;
561 fprintf_or_die(out, "%s\n", line.buf);
564 strbuf_release(&line);
565 fclose(in);
567 else if (errno != ENOENT)
568 die_errno(_("unable to read alternates file"));
570 if (found) {
571 rollback_lock_file(&lock);
572 } else {
573 fprintf_or_die(out, "%s\n", reference);
574 if (commit_lock_file(&lock))
575 die_errno(_("unable to move new alternates file into place"));
576 if (the_repository->objects->loaded_alternates)
577 link_alt_odb_entries(the_repository, reference,
578 '\n', NULL, 0);
580 free(alts);
583 void add_to_alternates_memory(const char *reference)
586 * Make sure alternates are initialized, or else our entry may be
587 * overwritten when they are.
589 prepare_alt_odb(the_repository);
591 link_alt_odb_entries(the_repository, reference,
592 '\n', NULL, 0);
596 * Compute the exact path an alternate is at and returns it. In case of
597 * error NULL is returned and the human readable error is added to `err`
598 * `path` may be relative and should point to $GIT_DIR.
599 * `err` must not be null.
601 char *compute_alternate_path(const char *path, struct strbuf *err)
603 char *ref_git = NULL;
604 const char *repo, *ref_git_s;
605 int seen_error = 0;
607 ref_git_s = real_path_if_valid(path);
608 if (!ref_git_s) {
609 seen_error = 1;
610 strbuf_addf(err, _("path '%s' does not exist"), path);
611 goto out;
612 } else
614 * Beware: read_gitfile(), real_path() and mkpath()
615 * return static buffer
617 ref_git = xstrdup(ref_git_s);
619 repo = read_gitfile(ref_git);
620 if (!repo)
621 repo = read_gitfile(mkpath("%s/.git", ref_git));
622 if (repo) {
623 free(ref_git);
624 ref_git = xstrdup(repo);
627 if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
628 char *ref_git_git = mkpathdup("%s/.git", ref_git);
629 free(ref_git);
630 ref_git = ref_git_git;
631 } else if (!is_directory(mkpath("%s/objects", ref_git))) {
632 struct strbuf sb = STRBUF_INIT;
633 seen_error = 1;
634 if (get_common_dir(&sb, ref_git)) {
635 strbuf_addf(err,
636 _("reference repository '%s' as a linked "
637 "checkout is not supported yet."),
638 path);
639 goto out;
642 strbuf_addf(err, _("reference repository '%s' is not a "
643 "local repository."), path);
644 goto out;
647 if (!access(mkpath("%s/shallow", ref_git), F_OK)) {
648 strbuf_addf(err, _("reference repository '%s' is shallow"),
649 path);
650 seen_error = 1;
651 goto out;
654 if (!access(mkpath("%s/info/grafts", ref_git), F_OK)) {
655 strbuf_addf(err,
656 _("reference repository '%s' is grafted"),
657 path);
658 seen_error = 1;
659 goto out;
662 out:
663 if (seen_error) {
664 FREE_AND_NULL(ref_git);
667 return ref_git;
670 int foreach_alt_odb(alt_odb_fn fn, void *cb)
672 struct object_directory *ent;
673 int r = 0;
675 prepare_alt_odb(the_repository);
676 for (ent = the_repository->objects->odb->next; ent; ent = ent->next) {
677 r = fn(ent, cb);
678 if (r)
679 break;
681 return r;
684 void prepare_alt_odb(struct repository *r)
686 if (r->objects->loaded_alternates)
687 return;
689 link_alt_odb_entries(r, r->objects->alternate_db, PATH_SEP, NULL, 0);
691 read_info_alternates(r, r->objects->odb->path, 0);
692 r->objects->loaded_alternates = 1;
695 /* Returns 1 if we have successfully freshened the file, 0 otherwise. */
696 static int freshen_file(const char *fn)
698 struct utimbuf t;
699 t.actime = t.modtime = time(NULL);
700 return !utime(fn, &t);
704 * All of the check_and_freshen functions return 1 if the file exists and was
705 * freshened (if freshening was requested), 0 otherwise. If they return
706 * 0, you should not assume that it is safe to skip a write of the object (it
707 * either does not exist on disk, or has a stale mtime and may be subject to
708 * pruning).
710 int check_and_freshen_file(const char *fn, int freshen)
712 if (access(fn, F_OK))
713 return 0;
714 if (freshen && !freshen_file(fn))
715 return 0;
716 return 1;
719 static int check_and_freshen_odb(struct object_directory *odb,
720 const struct object_id *oid,
721 int freshen)
723 static struct strbuf path = STRBUF_INIT;
724 odb_loose_path(odb, &path, oid->hash);
725 return check_and_freshen_file(path.buf, freshen);
728 static int check_and_freshen_local(const struct object_id *oid, int freshen)
730 return check_and_freshen_odb(the_repository->objects->odb, oid, freshen);
733 static int check_and_freshen_nonlocal(const struct object_id *oid, int freshen)
735 struct object_directory *odb;
737 prepare_alt_odb(the_repository);
738 for (odb = the_repository->objects->odb->next; odb; odb = odb->next) {
739 if (check_and_freshen_odb(odb, oid, freshen))
740 return 1;
742 return 0;
745 static int check_and_freshen(const struct object_id *oid, int freshen)
747 return check_and_freshen_local(oid, freshen) ||
748 check_and_freshen_nonlocal(oid, freshen);
751 int has_loose_object_nonlocal(const struct object_id *oid)
753 return check_and_freshen_nonlocal(oid, 0);
756 static int has_loose_object(const struct object_id *oid)
758 return check_and_freshen(oid, 0);
761 static void mmap_limit_check(size_t length)
763 static size_t limit = 0;
764 if (!limit) {
765 limit = git_env_ulong("GIT_MMAP_LIMIT", 0);
766 if (!limit)
767 limit = SIZE_MAX;
769 if (length > limit)
770 die(_("attempting to mmap %"PRIuMAX" over limit %"PRIuMAX),
771 (uintmax_t)length, (uintmax_t)limit);
774 void *xmmap_gently(void *start, size_t length,
775 int prot, int flags, int fd, off_t offset)
777 void *ret;
779 mmap_limit_check(length);
780 ret = mmap(start, length, prot, flags, fd, offset);
781 if (ret == MAP_FAILED) {
782 if (!length)
783 return NULL;
784 release_pack_memory(length);
785 ret = mmap(start, length, prot, flags, fd, offset);
787 return ret;
790 void *xmmap(void *start, size_t length,
791 int prot, int flags, int fd, off_t offset)
793 void *ret = xmmap_gently(start, length, prot, flags, fd, offset);
794 if (ret == MAP_FAILED)
795 die_errno(_("mmap failed"));
796 return ret;
800 * With an in-core object data in "map", rehash it to make sure the
801 * object name actually matches "sha1" to detect object corruption.
802 * With "map" == NULL, try reading the object named with "sha1" using
803 * the streaming interface and rehash it to do the same.
805 int check_object_signature(const struct object_id *oid, void *map,
806 unsigned long size, const char *type)
808 struct object_id real_oid;
809 enum object_type obj_type;
810 struct git_istream *st;
811 git_hash_ctx c;
812 char hdr[MAX_HEADER_LEN];
813 int hdrlen;
815 if (map) {
816 hash_object_file(map, size, type, &real_oid);
817 return !oideq(oid, &real_oid) ? -1 : 0;
820 st = open_istream(oid, &obj_type, &size, NULL);
821 if (!st)
822 return -1;
824 /* Generate the header */
825 hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %"PRIuMAX , type_name(obj_type), (uintmax_t)size) + 1;
827 /* Sha1.. */
828 the_hash_algo->init_fn(&c);
829 the_hash_algo->update_fn(&c, hdr, hdrlen);
830 for (;;) {
831 char buf[1024 * 16];
832 ssize_t readlen = read_istream(st, buf, sizeof(buf));
834 if (readlen < 0) {
835 close_istream(st);
836 return -1;
838 if (!readlen)
839 break;
840 the_hash_algo->update_fn(&c, buf, readlen);
842 the_hash_algo->final_fn(real_oid.hash, &c);
843 close_istream(st);
844 return !oideq(oid, &real_oid) ? -1 : 0;
847 int git_open_cloexec(const char *name, int flags)
849 int fd;
850 static int o_cloexec = O_CLOEXEC;
852 fd = open(name, flags | o_cloexec);
853 if ((o_cloexec & O_CLOEXEC) && fd < 0 && errno == EINVAL) {
854 /* Try again w/o O_CLOEXEC: the kernel might not support it */
855 o_cloexec &= ~O_CLOEXEC;
856 fd = open(name, flags | o_cloexec);
859 #if defined(F_GETFD) && defined(F_SETFD) && defined(FD_CLOEXEC)
861 static int fd_cloexec = FD_CLOEXEC;
863 if (!o_cloexec && 0 <= fd && fd_cloexec) {
864 /* Opened w/o O_CLOEXEC? try with fcntl(2) to add it */
865 int flags = fcntl(fd, F_GETFD);
866 if (fcntl(fd, F_SETFD, flags | fd_cloexec))
867 fd_cloexec = 0;
870 #endif
871 return fd;
875 * Find "sha1" as a loose object in the local repository or in an alternate.
876 * Returns 0 on success, negative on failure.
878 * The "path" out-parameter will give the path of the object we found (if any).
879 * Note that it may point to static storage and is only valid until another
880 * call to stat_sha1_file().
882 static int stat_sha1_file(struct repository *r, const unsigned char *sha1,
883 struct stat *st, const char **path)
885 struct object_directory *odb;
886 static struct strbuf buf = STRBUF_INIT;
888 prepare_alt_odb(r);
889 for (odb = r->objects->odb; odb; odb = odb->next) {
890 *path = odb_loose_path(odb, &buf, sha1);
891 if (!lstat(*path, st))
892 return 0;
895 return -1;
899 * Like stat_sha1_file(), but actually open the object and return the
900 * descriptor. See the caveats on the "path" parameter above.
902 static int open_sha1_file(struct repository *r,
903 const unsigned char *sha1, const char **path)
905 int fd;
906 struct object_directory *odb;
907 int most_interesting_errno = ENOENT;
908 static struct strbuf buf = STRBUF_INIT;
910 prepare_alt_odb(r);
911 for (odb = r->objects->odb; odb; odb = odb->next) {
912 *path = odb_loose_path(odb, &buf, sha1);
913 fd = git_open(*path);
914 if (fd >= 0)
915 return fd;
917 if (most_interesting_errno == ENOENT)
918 most_interesting_errno = errno;
920 errno = most_interesting_errno;
921 return -1;
924 static int quick_has_loose(struct repository *r,
925 const unsigned char *sha1)
927 int subdir_nr = sha1[0];
928 struct object_id oid;
929 struct object_directory *odb;
931 hashcpy(oid.hash, sha1);
933 prepare_alt_odb(r);
934 for (odb = r->objects->odb; odb; odb = odb->next) {
935 odb_load_loose_cache(odb, subdir_nr);
936 if (oid_array_lookup(&odb->loose_objects_cache, &oid) >= 0)
937 return 1;
939 return 0;
943 * Map the loose object at "path" if it is not NULL, or the path found by
944 * searching for a loose object named "sha1".
946 static void *map_sha1_file_1(struct repository *r, const char *path,
947 const unsigned char *sha1, unsigned long *size)
949 void *map;
950 int fd;
952 if (path)
953 fd = git_open(path);
954 else
955 fd = open_sha1_file(r, sha1, &path);
956 map = NULL;
957 if (fd >= 0) {
958 struct stat st;
960 if (!fstat(fd, &st)) {
961 *size = xsize_t(st.st_size);
962 if (!*size) {
963 /* mmap() is forbidden on empty files */
964 error(_("object file %s is empty"), path);
965 return NULL;
967 map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
969 close(fd);
971 return map;
974 void *map_sha1_file(struct repository *r,
975 const unsigned char *sha1, unsigned long *size)
977 return map_sha1_file_1(r, NULL, sha1, size);
980 static int unpack_sha1_short_header(git_zstream *stream,
981 unsigned char *map, unsigned long mapsize,
982 void *buffer, unsigned long bufsiz)
984 /* Get the data stream */
985 memset(stream, 0, sizeof(*stream));
986 stream->next_in = map;
987 stream->avail_in = mapsize;
988 stream->next_out = buffer;
989 stream->avail_out = bufsiz;
991 git_inflate_init(stream);
992 return git_inflate(stream, 0);
995 int unpack_sha1_header(git_zstream *stream,
996 unsigned char *map, unsigned long mapsize,
997 void *buffer, unsigned long bufsiz)
999 int status = unpack_sha1_short_header(stream, map, mapsize,
1000 buffer, bufsiz);
1002 if (status < Z_OK)
1003 return status;
1005 /* Make sure we have the terminating NUL */
1006 if (!memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
1007 return -1;
1008 return 0;
1011 static int unpack_sha1_header_to_strbuf(git_zstream *stream, unsigned char *map,
1012 unsigned long mapsize, void *buffer,
1013 unsigned long bufsiz, struct strbuf *header)
1015 int status;
1017 status = unpack_sha1_short_header(stream, map, mapsize, buffer, bufsiz);
1018 if (status < Z_OK)
1019 return -1;
1022 * Check if entire header is unpacked in the first iteration.
1024 if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
1025 return 0;
1028 * buffer[0..bufsiz] was not large enough. Copy the partial
1029 * result out to header, and then append the result of further
1030 * reading the stream.
1032 strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
1033 stream->next_out = buffer;
1034 stream->avail_out = bufsiz;
1036 do {
1037 status = git_inflate(stream, 0);
1038 strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
1039 if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
1040 return 0;
1041 stream->next_out = buffer;
1042 stream->avail_out = bufsiz;
1043 } while (status != Z_STREAM_END);
1044 return -1;
1047 static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
1049 int bytes = strlen(buffer) + 1;
1050 unsigned char *buf = xmallocz(size);
1051 unsigned long n;
1052 int status = Z_OK;
1054 n = stream->total_out - bytes;
1055 if (n > size)
1056 n = size;
1057 memcpy(buf, (char *) buffer + bytes, n);
1058 bytes = n;
1059 if (bytes <= size) {
1061 * The above condition must be (bytes <= size), not
1062 * (bytes < size). In other words, even though we
1063 * expect no more output and set avail_out to zero,
1064 * the input zlib stream may have bytes that express
1065 * "this concludes the stream", and we *do* want to
1066 * eat that input.
1068 * Otherwise we would not be able to test that we
1069 * consumed all the input to reach the expected size;
1070 * we also want to check that zlib tells us that all
1071 * went well with status == Z_STREAM_END at the end.
1073 stream->next_out = buf + bytes;
1074 stream->avail_out = size - bytes;
1075 while (status == Z_OK)
1076 status = git_inflate(stream, Z_FINISH);
1078 if (status == Z_STREAM_END && !stream->avail_in) {
1079 git_inflate_end(stream);
1080 return buf;
1083 if (status < 0)
1084 error(_("corrupt loose object '%s'"), sha1_to_hex(sha1));
1085 else if (stream->avail_in)
1086 error(_("garbage at end of loose object '%s'"),
1087 sha1_to_hex(sha1));
1088 free(buf);
1089 return NULL;
1093 * We used to just use "sscanf()", but that's actually way
1094 * too permissive for what we want to check. So do an anal
1095 * object header parse by hand.
1097 static int parse_sha1_header_extended(const char *hdr, struct object_info *oi,
1098 unsigned int flags)
1100 const char *type_buf = hdr;
1101 unsigned long size;
1102 int type, type_len = 0;
1105 * The type can be of any size but is followed by
1106 * a space.
1108 for (;;) {
1109 char c = *hdr++;
1110 if (!c)
1111 return -1;
1112 if (c == ' ')
1113 break;
1114 type_len++;
1117 type = type_from_string_gently(type_buf, type_len, 1);
1118 if (oi->type_name)
1119 strbuf_add(oi->type_name, type_buf, type_len);
1121 * Set type to 0 if its an unknown object and
1122 * we're obtaining the type using '--allow-unknown-type'
1123 * option.
1125 if ((flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE) && (type < 0))
1126 type = 0;
1127 else if (type < 0)
1128 die(_("invalid object type"));
1129 if (oi->typep)
1130 *oi->typep = type;
1133 * The length must follow immediately, and be in canonical
1134 * decimal format (ie "010" is not valid).
1136 size = *hdr++ - '0';
1137 if (size > 9)
1138 return -1;
1139 if (size) {
1140 for (;;) {
1141 unsigned long c = *hdr - '0';
1142 if (c > 9)
1143 break;
1144 hdr++;
1145 size = size * 10 + c;
1149 if (oi->sizep)
1150 *oi->sizep = size;
1153 * The length must be followed by a zero byte
1155 return *hdr ? -1 : type;
1158 int parse_sha1_header(const char *hdr, unsigned long *sizep)
1160 struct object_info oi = OBJECT_INFO_INIT;
1162 oi.sizep = sizep;
1163 return parse_sha1_header_extended(hdr, &oi, 0);
1166 static int sha1_loose_object_info(struct repository *r,
1167 const unsigned char *sha1,
1168 struct object_info *oi, int flags)
1170 int status = 0;
1171 unsigned long mapsize;
1172 void *map;
1173 git_zstream stream;
1174 char hdr[MAX_HEADER_LEN];
1175 struct strbuf hdrbuf = STRBUF_INIT;
1176 unsigned long size_scratch;
1178 if (oi->delta_base_sha1)
1179 hashclr(oi->delta_base_sha1);
1182 * If we don't care about type or size, then we don't
1183 * need to look inside the object at all. Note that we
1184 * do not optimize out the stat call, even if the
1185 * caller doesn't care about the disk-size, since our
1186 * return value implicitly indicates whether the
1187 * object even exists.
1189 if (!oi->typep && !oi->type_name && !oi->sizep && !oi->contentp) {
1190 const char *path;
1191 struct stat st;
1192 if (!oi->disk_sizep && (flags & OBJECT_INFO_QUICK))
1193 return quick_has_loose(r, sha1) ? 0 : -1;
1194 if (stat_sha1_file(r, sha1, &st, &path) < 0)
1195 return -1;
1196 if (oi->disk_sizep)
1197 *oi->disk_sizep = st.st_size;
1198 return 0;
1201 map = map_sha1_file(r, sha1, &mapsize);
1202 if (!map)
1203 return -1;
1205 if (!oi->sizep)
1206 oi->sizep = &size_scratch;
1208 if (oi->disk_sizep)
1209 *oi->disk_sizep = mapsize;
1210 if ((flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE)) {
1211 if (unpack_sha1_header_to_strbuf(&stream, map, mapsize, hdr, sizeof(hdr), &hdrbuf) < 0)
1212 status = error(_("unable to unpack %s header with --allow-unknown-type"),
1213 sha1_to_hex(sha1));
1214 } else if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
1215 status = error(_("unable to unpack %s header"),
1216 sha1_to_hex(sha1));
1217 if (status < 0)
1218 ; /* Do nothing */
1219 else if (hdrbuf.len) {
1220 if ((status = parse_sha1_header_extended(hdrbuf.buf, oi, flags)) < 0)
1221 status = error(_("unable to parse %s header with --allow-unknown-type"),
1222 sha1_to_hex(sha1));
1223 } else if ((status = parse_sha1_header_extended(hdr, oi, flags)) < 0)
1224 status = error(_("unable to parse %s header"), sha1_to_hex(sha1));
1226 if (status >= 0 && oi->contentp) {
1227 *oi->contentp = unpack_sha1_rest(&stream, hdr,
1228 *oi->sizep, sha1);
1229 if (!*oi->contentp) {
1230 git_inflate_end(&stream);
1231 status = -1;
1233 } else
1234 git_inflate_end(&stream);
1236 munmap(map, mapsize);
1237 if (status && oi->typep)
1238 *oi->typep = status;
1239 if (oi->sizep == &size_scratch)
1240 oi->sizep = NULL;
1241 strbuf_release(&hdrbuf);
1242 oi->whence = OI_LOOSE;
1243 return (status < 0) ? status : 0;
1246 int fetch_if_missing = 1;
1248 int oid_object_info_extended(struct repository *r, const struct object_id *oid,
1249 struct object_info *oi, unsigned flags)
1251 static struct object_info blank_oi = OBJECT_INFO_INIT;
1252 struct pack_entry e;
1253 int rtype;
1254 const struct object_id *real = oid;
1255 int already_retried = 0;
1257 if (flags & OBJECT_INFO_LOOKUP_REPLACE)
1258 real = lookup_replace_object(r, oid);
1260 if (is_null_oid(real))
1261 return -1;
1263 if (!oi)
1264 oi = &blank_oi;
1266 if (!(flags & OBJECT_INFO_SKIP_CACHED)) {
1267 struct cached_object *co = find_cached_object(real);
1268 if (co) {
1269 if (oi->typep)
1270 *(oi->typep) = co->type;
1271 if (oi->sizep)
1272 *(oi->sizep) = co->size;
1273 if (oi->disk_sizep)
1274 *(oi->disk_sizep) = 0;
1275 if (oi->delta_base_sha1)
1276 hashclr(oi->delta_base_sha1);
1277 if (oi->type_name)
1278 strbuf_addstr(oi->type_name, type_name(co->type));
1279 if (oi->contentp)
1280 *oi->contentp = xmemdupz(co->buf, co->size);
1281 oi->whence = OI_CACHED;
1282 return 0;
1286 while (1) {
1287 if (find_pack_entry(r, real, &e))
1288 break;
1290 if (flags & OBJECT_INFO_IGNORE_LOOSE)
1291 return -1;
1293 /* Most likely it's a loose object. */
1294 if (!sha1_loose_object_info(r, real->hash, oi, flags))
1295 return 0;
1297 /* Not a loose object; someone else may have just packed it. */
1298 if (!(flags & OBJECT_INFO_QUICK)) {
1299 reprepare_packed_git(r);
1300 if (find_pack_entry(r, real, &e))
1301 break;
1304 /* Check if it is a missing object */
1305 if (fetch_if_missing && repository_format_partial_clone &&
1306 !already_retried && r == the_repository) {
1308 * TODO Investigate having fetch_object() return
1309 * TODO error/success and stopping the music here.
1310 * TODO Pass a repository struct through fetch_object,
1311 * such that arbitrary repositories work.
1313 fetch_objects(repository_format_partial_clone, real, 1);
1314 already_retried = 1;
1315 continue;
1318 return -1;
1321 if (oi == &blank_oi)
1323 * We know that the caller doesn't actually need the
1324 * information below, so return early.
1326 return 0;
1327 rtype = packed_object_info(r, e.p, e.offset, oi);
1328 if (rtype < 0) {
1329 mark_bad_packed_object(e.p, real->hash);
1330 return oid_object_info_extended(r, real, oi, 0);
1331 } else if (oi->whence == OI_PACKED) {
1332 oi->u.packed.offset = e.offset;
1333 oi->u.packed.pack = e.p;
1334 oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
1335 rtype == OBJ_OFS_DELTA);
1338 return 0;
1341 /* returns enum object_type or negative */
1342 int oid_object_info(struct repository *r,
1343 const struct object_id *oid,
1344 unsigned long *sizep)
1346 enum object_type type;
1347 struct object_info oi = OBJECT_INFO_INIT;
1349 oi.typep = &type;
1350 oi.sizep = sizep;
1351 if (oid_object_info_extended(r, oid, &oi,
1352 OBJECT_INFO_LOOKUP_REPLACE) < 0)
1353 return -1;
1354 return type;
1357 static void *read_object(const unsigned char *sha1, enum object_type *type,
1358 unsigned long *size)
1360 struct object_id oid;
1361 struct object_info oi = OBJECT_INFO_INIT;
1362 void *content;
1363 oi.typep = type;
1364 oi.sizep = size;
1365 oi.contentp = &content;
1367 hashcpy(oid.hash, sha1);
1369 if (oid_object_info_extended(the_repository, &oid, &oi, 0) < 0)
1370 return NULL;
1371 return content;
1374 int pretend_object_file(void *buf, unsigned long len, enum object_type type,
1375 struct object_id *oid)
1377 struct cached_object *co;
1379 hash_object_file(buf, len, type_name(type), oid);
1380 if (has_sha1_file(oid->hash) || find_cached_object(oid))
1381 return 0;
1382 ALLOC_GROW(cached_objects, cached_object_nr + 1, cached_object_alloc);
1383 co = &cached_objects[cached_object_nr++];
1384 co->size = len;
1385 co->type = type;
1386 co->buf = xmalloc(len);
1387 memcpy(co->buf, buf, len);
1388 oidcpy(&co->oid, oid);
1389 return 0;
1393 * This function dies on corrupt objects; the callers who want to
1394 * deal with them should arrange to call read_object() and give error
1395 * messages themselves.
1397 void *read_object_file_extended(const struct object_id *oid,
1398 enum object_type *type,
1399 unsigned long *size,
1400 int lookup_replace)
1402 void *data;
1403 const struct packed_git *p;
1404 const char *path;
1405 struct stat st;
1406 const struct object_id *repl = lookup_replace ?
1407 lookup_replace_object(the_repository, oid) : oid;
1409 errno = 0;
1410 data = read_object(repl->hash, type, size);
1411 if (data)
1412 return data;
1414 if (errno && errno != ENOENT)
1415 die_errno(_("failed to read object %s"), oid_to_hex(oid));
1417 /* die if we replaced an object with one that does not exist */
1418 if (repl != oid)
1419 die(_("replacement %s not found for %s"),
1420 oid_to_hex(repl), oid_to_hex(oid));
1422 if (!stat_sha1_file(the_repository, repl->hash, &st, &path))
1423 die(_("loose object %s (stored in %s) is corrupt"),
1424 oid_to_hex(repl), path);
1426 if ((p = has_packed_and_bad(repl->hash)) != NULL)
1427 die(_("packed object %s (stored in %s) is corrupt"),
1428 oid_to_hex(repl), p->pack_name);
1430 return NULL;
1433 void *read_object_with_reference(const struct object_id *oid,
1434 const char *required_type_name,
1435 unsigned long *size,
1436 struct object_id *actual_oid_return)
1438 enum object_type type, required_type;
1439 void *buffer;
1440 unsigned long isize;
1441 struct object_id actual_oid;
1443 required_type = type_from_string(required_type_name);
1444 oidcpy(&actual_oid, oid);
1445 while (1) {
1446 int ref_length = -1;
1447 const char *ref_type = NULL;
1449 buffer = read_object_file(&actual_oid, &type, &isize);
1450 if (!buffer)
1451 return NULL;
1452 if (type == required_type) {
1453 *size = isize;
1454 if (actual_oid_return)
1455 oidcpy(actual_oid_return, &actual_oid);
1456 return buffer;
1458 /* Handle references */
1459 else if (type == OBJ_COMMIT)
1460 ref_type = "tree ";
1461 else if (type == OBJ_TAG)
1462 ref_type = "object ";
1463 else {
1464 free(buffer);
1465 return NULL;
1467 ref_length = strlen(ref_type);
1469 if (ref_length + the_hash_algo->hexsz > isize ||
1470 memcmp(buffer, ref_type, ref_length) ||
1471 get_oid_hex((char *) buffer + ref_length, &actual_oid)) {
1472 free(buffer);
1473 return NULL;
1475 free(buffer);
1476 /* Now we have the ID of the referred-to object in
1477 * actual_oid. Check again. */
1481 static void write_object_file_prepare(const void *buf, unsigned long len,
1482 const char *type, struct object_id *oid,
1483 char *hdr, int *hdrlen)
1485 git_hash_ctx c;
1487 /* Generate the header */
1488 *hdrlen = xsnprintf(hdr, *hdrlen, "%s %"PRIuMAX , type, (uintmax_t)len)+1;
1490 /* Sha1.. */
1491 the_hash_algo->init_fn(&c);
1492 the_hash_algo->update_fn(&c, hdr, *hdrlen);
1493 the_hash_algo->update_fn(&c, buf, len);
1494 the_hash_algo->final_fn(oid->hash, &c);
1498 * Move the just written object into its final resting place.
1500 int finalize_object_file(const char *tmpfile, const char *filename)
1502 int ret = 0;
1504 if (object_creation_mode == OBJECT_CREATION_USES_RENAMES)
1505 goto try_rename;
1506 else if (link(tmpfile, filename))
1507 ret = errno;
1510 * Coda hack - coda doesn't like cross-directory links,
1511 * so we fall back to a rename, which will mean that it
1512 * won't be able to check collisions, but that's not a
1513 * big deal.
1515 * The same holds for FAT formatted media.
1517 * When this succeeds, we just return. We have nothing
1518 * left to unlink.
1520 if (ret && ret != EEXIST) {
1521 try_rename:
1522 if (!rename(tmpfile, filename))
1523 goto out;
1524 ret = errno;
1526 unlink_or_warn(tmpfile);
1527 if (ret) {
1528 if (ret != EEXIST) {
1529 return error_errno(_("unable to write sha1 filename %s"), filename);
1531 /* FIXME!!! Collision check here ? */
1534 out:
1535 if (adjust_shared_perm(filename))
1536 return error(_("unable to set permission to '%s'"), filename);
1537 return 0;
1540 static int write_buffer(int fd, const void *buf, size_t len)
1542 if (write_in_full(fd, buf, len) < 0)
1543 return error_errno(_("file write error"));
1544 return 0;
1547 int hash_object_file(const void *buf, unsigned long len, const char *type,
1548 struct object_id *oid)
1550 char hdr[MAX_HEADER_LEN];
1551 int hdrlen = sizeof(hdr);
1552 write_object_file_prepare(buf, len, type, oid, hdr, &hdrlen);
1553 return 0;
1556 /* Finalize a file on disk, and close it. */
1557 static void close_sha1_file(int fd)
1559 if (fsync_object_files)
1560 fsync_or_die(fd, "sha1 file");
1561 if (close(fd) != 0)
1562 die_errno(_("error when closing sha1 file"));
1565 /* Size of directory component, including the ending '/' */
1566 static inline int directory_size(const char *filename)
1568 const char *s = strrchr(filename, '/');
1569 if (!s)
1570 return 0;
1571 return s - filename + 1;
1575 * This creates a temporary file in the same directory as the final
1576 * 'filename'
1578 * We want to avoid cross-directory filename renames, because those
1579 * can have problems on various filesystems (FAT, NFS, Coda).
1581 static int create_tmpfile(struct strbuf *tmp, const char *filename)
1583 int fd, dirlen = directory_size(filename);
1585 strbuf_reset(tmp);
1586 strbuf_add(tmp, filename, dirlen);
1587 strbuf_addstr(tmp, "tmp_obj_XXXXXX");
1588 fd = git_mkstemp_mode(tmp->buf, 0444);
1589 if (fd < 0 && dirlen && errno == ENOENT) {
1591 * Make sure the directory exists; note that the contents
1592 * of the buffer are undefined after mkstemp returns an
1593 * error, so we have to rewrite the whole buffer from
1594 * scratch.
1596 strbuf_reset(tmp);
1597 strbuf_add(tmp, filename, dirlen - 1);
1598 if (mkdir(tmp->buf, 0777) && errno != EEXIST)
1599 return -1;
1600 if (adjust_shared_perm(tmp->buf))
1601 return -1;
1603 /* Try again */
1604 strbuf_addstr(tmp, "/tmp_obj_XXXXXX");
1605 fd = git_mkstemp_mode(tmp->buf, 0444);
1607 return fd;
1610 static int write_loose_object(const struct object_id *oid, char *hdr,
1611 int hdrlen, const void *buf, unsigned long len,
1612 time_t mtime)
1614 int fd, ret;
1615 unsigned char compressed[4096];
1616 git_zstream stream;
1617 git_hash_ctx c;
1618 struct object_id parano_oid;
1619 static struct strbuf tmp_file = STRBUF_INIT;
1620 static struct strbuf filename = STRBUF_INIT;
1622 loose_object_path(the_repository, &filename, oid->hash);
1624 fd = create_tmpfile(&tmp_file, filename.buf);
1625 if (fd < 0) {
1626 if (errno == EACCES)
1627 return error(_("insufficient permission for adding an object to repository database %s"), get_object_directory());
1628 else
1629 return error_errno(_("unable to create temporary file"));
1632 /* Set it up */
1633 git_deflate_init(&stream, zlib_compression_level);
1634 stream.next_out = compressed;
1635 stream.avail_out = sizeof(compressed);
1636 the_hash_algo->init_fn(&c);
1638 /* First header.. */
1639 stream.next_in = (unsigned char *)hdr;
1640 stream.avail_in = hdrlen;
1641 while (git_deflate(&stream, 0) == Z_OK)
1642 ; /* nothing */
1643 the_hash_algo->update_fn(&c, hdr, hdrlen);
1645 /* Then the data itself.. */
1646 stream.next_in = (void *)buf;
1647 stream.avail_in = len;
1648 do {
1649 unsigned char *in0 = stream.next_in;
1650 ret = git_deflate(&stream, Z_FINISH);
1651 the_hash_algo->update_fn(&c, in0, stream.next_in - in0);
1652 if (write_buffer(fd, compressed, stream.next_out - compressed) < 0)
1653 die(_("unable to write sha1 file"));
1654 stream.next_out = compressed;
1655 stream.avail_out = sizeof(compressed);
1656 } while (ret == Z_OK);
1658 if (ret != Z_STREAM_END)
1659 die(_("unable to deflate new object %s (%d)"), oid_to_hex(oid),
1660 ret);
1661 ret = git_deflate_end_gently(&stream);
1662 if (ret != Z_OK)
1663 die(_("deflateEnd on object %s failed (%d)"), oid_to_hex(oid),
1664 ret);
1665 the_hash_algo->final_fn(parano_oid.hash, &c);
1666 if (!oideq(oid, &parano_oid))
1667 die(_("confused by unstable object source data for %s"),
1668 oid_to_hex(oid));
1670 close_sha1_file(fd);
1672 if (mtime) {
1673 struct utimbuf utb;
1674 utb.actime = mtime;
1675 utb.modtime = mtime;
1676 if (utime(tmp_file.buf, &utb) < 0)
1677 warning_errno(_("failed utime() on %s"), tmp_file.buf);
1680 return finalize_object_file(tmp_file.buf, filename.buf);
1683 static int freshen_loose_object(const struct object_id *oid)
1685 return check_and_freshen(oid, 1);
1688 static int freshen_packed_object(const struct object_id *oid)
1690 struct pack_entry e;
1691 if (!find_pack_entry(the_repository, oid, &e))
1692 return 0;
1693 if (e.p->freshened)
1694 return 1;
1695 if (!freshen_file(e.p->pack_name))
1696 return 0;
1697 e.p->freshened = 1;
1698 return 1;
1701 int write_object_file(const void *buf, unsigned long len, const char *type,
1702 struct object_id *oid)
1704 char hdr[MAX_HEADER_LEN];
1705 int hdrlen = sizeof(hdr);
1707 /* Normally if we have it in the pack then we do not bother writing
1708 * it out into .git/objects/??/?{38} file.
1710 write_object_file_prepare(buf, len, type, oid, hdr, &hdrlen);
1711 if (freshen_packed_object(oid) || freshen_loose_object(oid))
1712 return 0;
1713 return write_loose_object(oid, hdr, hdrlen, buf, len, 0);
1716 int hash_object_file_literally(const void *buf, unsigned long len,
1717 const char *type, struct object_id *oid,
1718 unsigned flags)
1720 char *header;
1721 int hdrlen, status = 0;
1723 /* type string, SP, %lu of the length plus NUL must fit this */
1724 hdrlen = strlen(type) + MAX_HEADER_LEN;
1725 header = xmalloc(hdrlen);
1726 write_object_file_prepare(buf, len, type, oid, header, &hdrlen);
1728 if (!(flags & HASH_WRITE_OBJECT))
1729 goto cleanup;
1730 if (freshen_packed_object(oid) || freshen_loose_object(oid))
1731 goto cleanup;
1732 status = write_loose_object(oid, header, hdrlen, buf, len, 0);
1734 cleanup:
1735 free(header);
1736 return status;
1739 int force_object_loose(const struct object_id *oid, time_t mtime)
1741 void *buf;
1742 unsigned long len;
1743 enum object_type type;
1744 char hdr[MAX_HEADER_LEN];
1745 int hdrlen;
1746 int ret;
1748 if (has_loose_object(oid))
1749 return 0;
1750 buf = read_object(oid->hash, &type, &len);
1751 if (!buf)
1752 return error(_("cannot read sha1_file for %s"), oid_to_hex(oid));
1753 hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %"PRIuMAX , type_name(type), (uintmax_t)len) + 1;
1754 ret = write_loose_object(oid, hdr, hdrlen, buf, len, mtime);
1755 free(buf);
1757 return ret;
1760 int has_sha1_file_with_flags(const unsigned char *sha1, int flags)
1762 struct object_id oid;
1763 if (!startup_info->have_repository)
1764 return 0;
1765 hashcpy(oid.hash, sha1);
1766 return oid_object_info_extended(the_repository, &oid, NULL,
1767 flags | OBJECT_INFO_SKIP_CACHED) >= 0;
1770 int has_object_file(const struct object_id *oid)
1772 return has_sha1_file(oid->hash);
1775 int has_object_file_with_flags(const struct object_id *oid, int flags)
1777 return has_sha1_file_with_flags(oid->hash, flags);
1780 static void check_tree(const void *buf, size_t size)
1782 struct tree_desc desc;
1783 struct name_entry entry;
1785 init_tree_desc(&desc, buf, size);
1786 while (tree_entry(&desc, &entry))
1787 /* do nothing
1788 * tree_entry() will die() on malformed entries */
1792 static void check_commit(const void *buf, size_t size)
1794 struct commit c;
1795 memset(&c, 0, sizeof(c));
1796 if (parse_commit_buffer(the_repository, &c, buf, size, 0))
1797 die(_("corrupt commit"));
1800 static void check_tag(const void *buf, size_t size)
1802 struct tag t;
1803 memset(&t, 0, sizeof(t));
1804 if (parse_tag_buffer(the_repository, &t, buf, size))
1805 die(_("corrupt tag"));
1808 static int index_mem(struct index_state *istate,
1809 struct object_id *oid, void *buf, size_t size,
1810 enum object_type type,
1811 const char *path, unsigned flags)
1813 int ret, re_allocated = 0;
1814 int write_object = flags & HASH_WRITE_OBJECT;
1816 if (!type)
1817 type = OBJ_BLOB;
1820 * Convert blobs to git internal format
1822 if ((type == OBJ_BLOB) && path) {
1823 struct strbuf nbuf = STRBUF_INIT;
1824 if (convert_to_git(istate, path, buf, size, &nbuf,
1825 get_conv_flags(flags))) {
1826 buf = strbuf_detach(&nbuf, &size);
1827 re_allocated = 1;
1830 if (flags & HASH_FORMAT_CHECK) {
1831 if (type == OBJ_TREE)
1832 check_tree(buf, size);
1833 if (type == OBJ_COMMIT)
1834 check_commit(buf, size);
1835 if (type == OBJ_TAG)
1836 check_tag(buf, size);
1839 if (write_object)
1840 ret = write_object_file(buf, size, type_name(type), oid);
1841 else
1842 ret = hash_object_file(buf, size, type_name(type), oid);
1843 if (re_allocated)
1844 free(buf);
1845 return ret;
1848 static int index_stream_convert_blob(struct index_state *istate,
1849 struct object_id *oid,
1850 int fd,
1851 const char *path,
1852 unsigned flags)
1854 int ret;
1855 const int write_object = flags & HASH_WRITE_OBJECT;
1856 struct strbuf sbuf = STRBUF_INIT;
1858 assert(path);
1859 assert(would_convert_to_git_filter_fd(istate, path));
1861 convert_to_git_filter_fd(istate, path, fd, &sbuf,
1862 get_conv_flags(flags));
1864 if (write_object)
1865 ret = write_object_file(sbuf.buf, sbuf.len, type_name(OBJ_BLOB),
1866 oid);
1867 else
1868 ret = hash_object_file(sbuf.buf, sbuf.len, type_name(OBJ_BLOB),
1869 oid);
1870 strbuf_release(&sbuf);
1871 return ret;
1874 static int index_pipe(struct index_state *istate, struct object_id *oid,
1875 int fd, enum object_type type,
1876 const char *path, unsigned flags)
1878 struct strbuf sbuf = STRBUF_INIT;
1879 int ret;
1881 if (strbuf_read(&sbuf, fd, 4096) >= 0)
1882 ret = index_mem(istate, oid, sbuf.buf, sbuf.len, type, path, flags);
1883 else
1884 ret = -1;
1885 strbuf_release(&sbuf);
1886 return ret;
1889 #define SMALL_FILE_SIZE (32*1024)
1891 static int index_core(struct index_state *istate,
1892 struct object_id *oid, int fd, size_t size,
1893 enum object_type type, const char *path,
1894 unsigned flags)
1896 int ret;
1898 if (!size) {
1899 ret = index_mem(istate, oid, "", size, type, path, flags);
1900 } else if (size <= SMALL_FILE_SIZE) {
1901 char *buf = xmalloc(size);
1902 ssize_t read_result = read_in_full(fd, buf, size);
1903 if (read_result < 0)
1904 ret = error_errno(_("read error while indexing %s"),
1905 path ? path : "<unknown>");
1906 else if (read_result != size)
1907 ret = error(_("short read while indexing %s"),
1908 path ? path : "<unknown>");
1909 else
1910 ret = index_mem(istate, oid, buf, size, type, path, flags);
1911 free(buf);
1912 } else {
1913 void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
1914 ret = index_mem(istate, oid, buf, size, type, path, flags);
1915 munmap(buf, size);
1917 return ret;
1921 * This creates one packfile per large blob unless bulk-checkin
1922 * machinery is "plugged".
1924 * This also bypasses the usual "convert-to-git" dance, and that is on
1925 * purpose. We could write a streaming version of the converting
1926 * functions and insert that before feeding the data to fast-import
1927 * (or equivalent in-core API described above). However, that is
1928 * somewhat complicated, as we do not know the size of the filter
1929 * result, which we need to know beforehand when writing a git object.
1930 * Since the primary motivation for trying to stream from the working
1931 * tree file and to avoid mmaping it in core is to deal with large
1932 * binary blobs, they generally do not want to get any conversion, and
1933 * callers should avoid this code path when filters are requested.
1935 static int index_stream(struct object_id *oid, int fd, size_t size,
1936 enum object_type type, const char *path,
1937 unsigned flags)
1939 return index_bulk_checkin(oid, fd, size, type, path, flags);
1942 int index_fd(struct index_state *istate, struct object_id *oid,
1943 int fd, struct stat *st,
1944 enum object_type type, const char *path, unsigned flags)
1946 int ret;
1949 * Call xsize_t() only when needed to avoid potentially unnecessary
1950 * die() for large files.
1952 if (type == OBJ_BLOB && path && would_convert_to_git_filter_fd(istate, path))
1953 ret = index_stream_convert_blob(istate, oid, fd, path, flags);
1954 else if (!S_ISREG(st->st_mode))
1955 ret = index_pipe(istate, oid, fd, type, path, flags);
1956 else if (st->st_size <= big_file_threshold || type != OBJ_BLOB ||
1957 (path && would_convert_to_git(istate, path)))
1958 ret = index_core(istate, oid, fd, xsize_t(st->st_size),
1959 type, path, flags);
1960 else
1961 ret = index_stream(oid, fd, xsize_t(st->st_size), type, path,
1962 flags);
1963 close(fd);
1964 return ret;
1967 int index_path(struct index_state *istate, struct object_id *oid,
1968 const char *path, struct stat *st, unsigned flags)
1970 int fd;
1971 struct strbuf sb = STRBUF_INIT;
1972 int rc = 0;
1974 switch (st->st_mode & S_IFMT) {
1975 case S_IFREG:
1976 fd = open(path, O_RDONLY);
1977 if (fd < 0)
1978 return error_errno("open(\"%s\")", path);
1979 if (index_fd(istate, oid, fd, st, OBJ_BLOB, path, flags) < 0)
1980 return error(_("%s: failed to insert into database"),
1981 path);
1982 break;
1983 case S_IFLNK:
1984 if (strbuf_readlink(&sb, path, st->st_size))
1985 return error_errno("readlink(\"%s\")", path);
1986 if (!(flags & HASH_WRITE_OBJECT))
1987 hash_object_file(sb.buf, sb.len, blob_type, oid);
1988 else if (write_object_file(sb.buf, sb.len, blob_type, oid))
1989 rc = error(_("%s: failed to insert into database"), path);
1990 strbuf_release(&sb);
1991 break;
1992 case S_IFDIR:
1993 return resolve_gitlink_ref(path, "HEAD", oid);
1994 default:
1995 return error(_("%s: unsupported file type"), path);
1997 return rc;
2000 int read_pack_header(int fd, struct pack_header *header)
2002 if (read_in_full(fd, header, sizeof(*header)) != sizeof(*header))
2003 /* "eof before pack header was fully read" */
2004 return PH_ERROR_EOF;
2006 if (header->hdr_signature != htonl(PACK_SIGNATURE))
2007 /* "protocol error (pack signature mismatch detected)" */
2008 return PH_ERROR_PACK_SIGNATURE;
2009 if (!pack_version_ok(header->hdr_version))
2010 /* "protocol error (pack version unsupported)" */
2011 return PH_ERROR_PROTOCOL;
2012 return 0;
2015 void assert_oid_type(const struct object_id *oid, enum object_type expect)
2017 enum object_type type = oid_object_info(the_repository, oid, NULL);
2018 if (type < 0)
2019 die(_("%s is not a valid object"), oid_to_hex(oid));
2020 if (type != expect)
2021 die(_("%s is not a valid '%s' object"), oid_to_hex(oid),
2022 type_name(expect));
2025 int for_each_file_in_obj_subdir(unsigned int subdir_nr,
2026 struct strbuf *path,
2027 each_loose_object_fn obj_cb,
2028 each_loose_cruft_fn cruft_cb,
2029 each_loose_subdir_fn subdir_cb,
2030 void *data)
2032 size_t origlen, baselen;
2033 DIR *dir;
2034 struct dirent *de;
2035 int r = 0;
2036 struct object_id oid;
2038 if (subdir_nr > 0xff)
2039 BUG("invalid loose object subdirectory: %x", subdir_nr);
2041 origlen = path->len;
2042 strbuf_complete(path, '/');
2043 strbuf_addf(path, "%02x", subdir_nr);
2045 dir = opendir(path->buf);
2046 if (!dir) {
2047 if (errno != ENOENT)
2048 r = error_errno(_("unable to open %s"), path->buf);
2049 strbuf_setlen(path, origlen);
2050 return r;
2053 oid.hash[0] = subdir_nr;
2054 strbuf_addch(path, '/');
2055 baselen = path->len;
2057 while ((de = readdir(dir))) {
2058 size_t namelen;
2059 if (is_dot_or_dotdot(de->d_name))
2060 continue;
2062 namelen = strlen(de->d_name);
2063 strbuf_setlen(path, baselen);
2064 strbuf_add(path, de->d_name, namelen);
2065 if (namelen == the_hash_algo->hexsz - 2 &&
2066 !hex_to_bytes(oid.hash + 1, de->d_name,
2067 the_hash_algo->rawsz - 1)) {
2068 if (obj_cb) {
2069 r = obj_cb(&oid, path->buf, data);
2070 if (r)
2071 break;
2073 continue;
2076 if (cruft_cb) {
2077 r = cruft_cb(de->d_name, path->buf, data);
2078 if (r)
2079 break;
2082 closedir(dir);
2084 strbuf_setlen(path, baselen - 1);
2085 if (!r && subdir_cb)
2086 r = subdir_cb(subdir_nr, path->buf, data);
2088 strbuf_setlen(path, origlen);
2090 return r;
2093 int for_each_loose_file_in_objdir_buf(struct strbuf *path,
2094 each_loose_object_fn obj_cb,
2095 each_loose_cruft_fn cruft_cb,
2096 each_loose_subdir_fn subdir_cb,
2097 void *data)
2099 int r = 0;
2100 int i;
2102 for (i = 0; i < 256; i++) {
2103 r = for_each_file_in_obj_subdir(i, path, obj_cb, cruft_cb,
2104 subdir_cb, data);
2105 if (r)
2106 break;
2109 return r;
2112 int for_each_loose_file_in_objdir(const char *path,
2113 each_loose_object_fn obj_cb,
2114 each_loose_cruft_fn cruft_cb,
2115 each_loose_subdir_fn subdir_cb,
2116 void *data)
2118 struct strbuf buf = STRBUF_INIT;
2119 int r;
2121 strbuf_addstr(&buf, path);
2122 r = for_each_loose_file_in_objdir_buf(&buf, obj_cb, cruft_cb,
2123 subdir_cb, data);
2124 strbuf_release(&buf);
2126 return r;
2129 int for_each_loose_object(each_loose_object_fn cb, void *data,
2130 enum for_each_object_flags flags)
2132 struct object_directory *odb;
2134 prepare_alt_odb(the_repository);
2135 for (odb = the_repository->objects->odb; odb; odb = odb->next) {
2136 int r = for_each_loose_file_in_objdir(odb->path, cb, NULL,
2137 NULL, data);
2138 if (r)
2139 return r;
2141 if (flags & FOR_EACH_OBJECT_LOCAL_ONLY)
2142 break;
2145 return 0;
2148 static int append_loose_object(const struct object_id *oid, const char *path,
2149 void *data)
2151 oid_array_append(data, oid);
2152 return 0;
2155 void odb_load_loose_cache(struct object_directory *odb, int subdir_nr)
2157 struct strbuf buf = STRBUF_INIT;
2159 if (subdir_nr < 0 ||
2160 subdir_nr >= ARRAY_SIZE(odb->loose_objects_subdir_seen))
2161 BUG("subdir_nr out of range");
2163 if (odb->loose_objects_subdir_seen[subdir_nr])
2164 return;
2166 strbuf_addstr(&buf, odb->path);
2167 for_each_file_in_obj_subdir(subdir_nr, &buf,
2168 append_loose_object,
2169 NULL, NULL,
2170 &odb->loose_objects_cache);
2171 odb->loose_objects_subdir_seen[subdir_nr] = 1;
2172 strbuf_release(&buf);
2175 static int check_stream_sha1(git_zstream *stream,
2176 const char *hdr,
2177 unsigned long size,
2178 const char *path,
2179 const unsigned char *expected_sha1)
2181 git_hash_ctx c;
2182 unsigned char real_sha1[GIT_MAX_RAWSZ];
2183 unsigned char buf[4096];
2184 unsigned long total_read;
2185 int status = Z_OK;
2187 the_hash_algo->init_fn(&c);
2188 the_hash_algo->update_fn(&c, hdr, stream->total_out);
2191 * We already read some bytes into hdr, but the ones up to the NUL
2192 * do not count against the object's content size.
2194 total_read = stream->total_out - strlen(hdr) - 1;
2197 * This size comparison must be "<=" to read the final zlib packets;
2198 * see the comment in unpack_sha1_rest for details.
2200 while (total_read <= size &&
2201 (status == Z_OK ||
2202 (status == Z_BUF_ERROR && !stream->avail_out))) {
2203 stream->next_out = buf;
2204 stream->avail_out = sizeof(buf);
2205 if (size - total_read < stream->avail_out)
2206 stream->avail_out = size - total_read;
2207 status = git_inflate(stream, Z_FINISH);
2208 the_hash_algo->update_fn(&c, buf, stream->next_out - buf);
2209 total_read += stream->next_out - buf;
2211 git_inflate_end(stream);
2213 if (status != Z_STREAM_END) {
2214 error(_("corrupt loose object '%s'"), sha1_to_hex(expected_sha1));
2215 return -1;
2217 if (stream->avail_in) {
2218 error(_("garbage at end of loose object '%s'"),
2219 sha1_to_hex(expected_sha1));
2220 return -1;
2223 the_hash_algo->final_fn(real_sha1, &c);
2224 if (!hasheq(expected_sha1, real_sha1)) {
2225 error(_("sha1 mismatch for %s (expected %s)"), path,
2226 sha1_to_hex(expected_sha1));
2227 return -1;
2230 return 0;
2233 int read_loose_object(const char *path,
2234 const struct object_id *expected_oid,
2235 enum object_type *type,
2236 unsigned long *size,
2237 void **contents)
2239 int ret = -1;
2240 void *map = NULL;
2241 unsigned long mapsize;
2242 git_zstream stream;
2243 char hdr[MAX_HEADER_LEN];
2245 *contents = NULL;
2247 map = map_sha1_file_1(the_repository, path, NULL, &mapsize);
2248 if (!map) {
2249 error_errno(_("unable to mmap %s"), path);
2250 goto out;
2253 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0) {
2254 error(_("unable to unpack header of %s"), path);
2255 goto out;
2258 *type = parse_sha1_header(hdr, size);
2259 if (*type < 0) {
2260 error(_("unable to parse header of %s"), path);
2261 git_inflate_end(&stream);
2262 goto out;
2265 if (*type == OBJ_BLOB && *size > big_file_threshold) {
2266 if (check_stream_sha1(&stream, hdr, *size, path, expected_oid->hash) < 0)
2267 goto out;
2268 } else {
2269 *contents = unpack_sha1_rest(&stream, hdr, *size, expected_oid->hash);
2270 if (!*contents) {
2271 error(_("unable to unpack contents of %s"), path);
2272 git_inflate_end(&stream);
2273 goto out;
2275 if (check_object_signature(expected_oid, *contents,
2276 *size, type_name(*type))) {
2277 error(_("sha1 mismatch for %s (expected %s)"), path,
2278 oid_to_hex(expected_oid));
2279 free(*contents);
2280 goto out;
2284 ret = 0; /* everything checks out */
2286 out:
2287 if (map)
2288 munmap(map, mapsize);
2289 return ret;