Prepare for 2.15.2
[git/git.git] / sha1_file.c
CommitLineData
0fcfd160
LT
1/*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) Linus Torvalds, 2005
5 *
6 * This handles basic git sha1 object files - packing, unpacking,
7 * creation etc.
8 */
0fcfd160 9#include "cache.h"
b2141fc1 10#include "config.h"
6eac50d8 11#include "string-list.h"
697cc8ef 12#include "lockfile.h"
1f688557 13#include "delta.h"
a733cb60 14#include "pack.h"
8e440259
PE
15#include "blob.h"
16#include "commit.h"
4dd1fbc7 17#include "run-command.h"
8e440259
PE
18#include "tag.h"
19#include "tree.h"
c879daa2 20#include "tree-walk.h"
f35a6d3b 21#include "refs.h"
70f5d5d3 22#include "pack-revindex.h"
628522ec 23#include "sha1-lookup.h"
568508e7 24#include "bulk-checkin.h"
090ea126 25#include "streaming.h"
543c5caa 26#include "dir.h"
a73cdd21 27#include "mru.h"
12d95ef6 28#include "list.h"
c4c6effa 29#include "mergesort.h"
cf3c6352 30#include "quote.h"
4f39cd82 31#include "packfile.h"
e05db0fd 32
50c5cd58 33const unsigned char null_sha1[GIT_MAX_RAWSZ];
3e56e724 34const struct object_id null_oid;
8576fde6
JK
35const struct object_id empty_tree_oid = {
36 EMPTY_TREE_SHA1_BIN_LITERAL
37};
38const struct object_id empty_blob_oid = {
39 EMPTY_BLOB_SHA1_BIN_LITERAL
40};
88cd621d 41
c597ba80
NTND
42/*
43 * This is meant to hold a *small* number of objects that you would
44 * want read_sha1_file() to be able to return, but yet you do not want
45 * to write them into the object store (e.g. a browse-only
46 * application).
47 */
48static struct cached_object {
49 unsigned char sha1[20];
50 enum object_type type;
51 void *buf;
52 unsigned long size;
53} *cached_objects;
54static int cached_object_nr, cached_object_alloc;
55
56static struct cached_object empty_tree = {
dab0d410 57 EMPTY_TREE_SHA1_BIN_LITERAL,
c597ba80
NTND
58 OBJ_TREE,
59 "",
60 0
61};
62
63static struct cached_object *find_cached_object(const unsigned char *sha1)
64{
65 int i;
66 struct cached_object *co = cached_objects;
67
68 for (i = 0; i < cached_object_nr; i++, co++) {
69 if (!hashcmp(co->sha1, sha1))
70 return co;
71 }
72 if (!hashcmp(sha1, empty_tree.sha1))
73 return &empty_tree;
74 return NULL;
75}
76
90a6464b
JH
77int mkdir_in_gitdir(const char *path)
78{
79 if (mkdir(path, 0777)) {
80 int saved_errno = errno;
81 struct stat st;
82 struct strbuf sb = STRBUF_INIT;
83
84 if (errno != EEXIST)
85 return -1;
86 /*
87 * Are we looking at a path in a symlinked worktree
88 * whose original repository does not yet have it?
89 * e.g. .git/rr-cache pointing at its original
90 * repository in which the user hasn't performed any
91 * conflict resolution yet?
92 */
93 if (lstat(path, &st) || !S_ISLNK(st.st_mode) ||
94 strbuf_readlink(&sb, path, st.st_size) ||
95 !is_absolute_path(sb.buf) ||
96 mkdir(sb.buf, 0777)) {
97 strbuf_release(&sb);
98 errno = saved_errno;
99 return -1;
100 }
101 strbuf_release(&sb);
102 }
103 return adjust_shared_perm(path);
104}
105
0be0521b 106enum scld_error safe_create_leading_directories(char *path)
b2cb9425 107{
26c8ae2a 108 char *next_component = path + offset_1st_component(path);
0be0521b 109 enum scld_error ret = SCLD_OK;
67d42212 110
0be0521b 111 while (ret == SCLD_OK && next_component) {
f0502332 112 struct stat st;
0f527403 113 char *slash = next_component, slash_character;
f0502332 114
0f527403
MH
115 while (*slash && !is_dir_sep(*slash))
116 slash++;
117
118 if (!*slash)
b2cb9425 119 break;
bf10cf70 120
26c8ae2a 121 next_component = slash + 1;
0f527403 122 while (is_dir_sep(*next_component))
bf10cf70 123 next_component++;
26c8ae2a 124 if (!*next_component)
5f0bdf50 125 break;
831651fd 126
0f527403 127 slash_character = *slash;
831651fd 128 *slash = '\0';
67d42212
JR
129 if (!stat(path, &st)) {
130 /* path exists */
204a047f
MH
131 if (!S_ISDIR(st.st_mode)) {
132 errno = ENOTDIR;
0be0521b 133 ret = SCLD_EXISTS;
204a047f 134 }
53a39721 135 } else if (mkdir(path, 0777)) {
928734d9 136 if (errno == EEXIST &&
9e6f885d 137 !stat(path, &st) && S_ISDIR(st.st_mode))
928734d9 138 ; /* somebody created it since we checked */
18d37e86
MH
139 else if (errno == ENOENT)
140 /*
141 * Either mkdir() failed because
142 * somebody just pruned the containing
143 * directory, or stat() failed because
144 * the file that was in our way was
145 * just removed. Either way, inform
146 * the caller that it might be worth
147 * trying again:
148 */
149 ret = SCLD_VANISHED;
9e6f885d 150 else
0be0521b 151 ret = SCLD_FAILED;
53a39721 152 } else if (adjust_shared_perm(path)) {
0be0521b 153 ret = SCLD_PERMS;
457f06d6 154 }
0f527403 155 *slash = slash_character;
b2cb9425 156 }
9e6f885d 157 return ret;
b2cb9425 158}
723c31fe 159
0be0521b 160enum scld_error safe_create_leading_directories_const(const char *path)
8e21d63b 161{
02944307 162 int save_errno;
8e21d63b
JK
163 /* path points to cache entries, so xstrdup before messing with it */
164 char *buf = xstrdup(path);
0be0521b 165 enum scld_error result = safe_create_leading_directories(buf);
02944307
MH
166
167 save_errno = errno;
8e21d63b 168 free(buf);
02944307 169 errno = save_errno;
8e21d63b
JK
170 return result;
171}
172
177978f5
MH
173int raceproof_create_file(const char *path, create_file_fn fn, void *cb)
174{
175 /*
176 * The number of times we will try to remove empty directories
177 * in the way of path. This is only 1 because if another
178 * process is racily creating directories that conflict with
179 * us, we don't want to fight against them.
180 */
181 int remove_directories_remaining = 1;
182
183 /*
184 * The number of times that we will try to create the
185 * directories containing path. We are willing to attempt this
186 * more than once, because another process could be trying to
187 * clean up empty directories at the same time as we are
188 * trying to create them.
189 */
190 int create_directories_remaining = 3;
191
192 /* A scratch copy of path, filled lazily if we need it: */
193 struct strbuf path_copy = STRBUF_INIT;
194
195 int ret, save_errno;
196
197 /* Sanity check: */
198 assert(*path);
199
200retry_fn:
201 ret = fn(path, cb);
202 save_errno = errno;
203 if (!ret)
204 goto out;
205
206 if (errno == EISDIR && remove_directories_remaining-- > 0) {
207 /*
208 * A directory is in the way. Maybe it is empty; try
209 * to remove it:
210 */
211 if (!path_copy.len)
212 strbuf_addstr(&path_copy, path);
213
214 if (!remove_dir_recursively(&path_copy, REMOVE_DIR_EMPTY_ONLY))
215 goto retry_fn;
216 } else if (errno == ENOENT && create_directories_remaining-- > 0) {
217 /*
218 * Maybe the containing directory didn't exist, or
219 * maybe it was just deleted by a process that is
220 * racing with us to clean up empty directories. Try
221 * to create it:
222 */
223 enum scld_error scld_result;
224
225 if (!path_copy.len)
226 strbuf_addstr(&path_copy, path);
227
228 do {
229 scld_result = safe_create_leading_directories(path_copy.buf);
230 if (scld_result == SCLD_OK)
231 goto retry_fn;
232 } while (scld_result == SCLD_VANISHED && create_directories_remaining-- > 0);
233 }
234
235out:
236 strbuf_release(&path_copy);
237 errno = save_errno;
238 return ret;
239}
240
f7b7774f 241static void fill_sha1_path(struct strbuf *buf, const unsigned char *sha1)
ace1534d
JH
242{
243 int i;
244 for (i = 0; i < 20; i++) {
245 static char hex[] = "0123456789abcdef";
246 unsigned int val = sha1[i];
f7b7774f
JK
247 strbuf_addch(buf, hex[val >> 4]);
248 strbuf_addch(buf, hex[val & 0xf]);
afbba2f0 249 if (!i)
f7b7774f 250 strbuf_addch(buf, '/');
ace1534d
JH
251 }
252}
253
30d6c6ea 254const char *sha1_file_name(const unsigned char *sha1)
0fcfd160 255{
f7b7774f 256 static struct strbuf buf = STRBUF_INIT;
0fcfd160 257
f7b7774f
JK
258 strbuf_reset(&buf);
259 strbuf_addf(&buf, "%s/", get_object_directory());
560fb6a1 260
f7b7774f
JK
261 fill_sha1_path(&buf, sha1);
262 return buf.buf;
0fcfd160
LT
263}
264
38dbe5f0
JK
265struct strbuf *alt_scratch_buf(struct alternate_object_database *alt)
266{
267 strbuf_setlen(&alt->scratch, alt->base_len);
268 return &alt->scratch;
269}
270
29ec6af2
JK
271static const char *alt_sha1_path(struct alternate_object_database *alt,
272 const unsigned char *sha1)
273{
38dbe5f0 274 struct strbuf *buf = alt_scratch_buf(alt);
f7b7774f 275 fill_sha1_path(buf, sha1);
38dbe5f0 276 return buf->buf;
0fcfd160
LT
277}
278
d5a63b99
JH
279struct alternate_object_database *alt_odb_list;
280static struct alternate_object_database **alt_odb_tail;
ace1534d 281
4ea82473
JK
282/*
283 * Return non-zero iff the path is usable as an alternate object database.
284 */
285static int alt_odb_usable(struct strbuf *path, const char *normalized_objdir)
286{
287 struct alternate_object_database *alt;
288
289 /* Detect cases where alternate disappeared */
290 if (!is_directory(path->buf)) {
291 error("object directory %s does not exist; "
292 "check .git/objects/info/alternates.",
293 path->buf);
294 return 0;
295 }
296
297 /*
298 * Prevent the common mistake of listing the same
299 * thing twice, or object directory itself.
300 */
301 for (alt = alt_odb_list; alt; alt = alt->next) {
ea0fc3b4 302 if (!fspathcmp(path->buf, alt->path))
4ea82473
JK
303 return 0;
304 }
305 if (!fspathcmp(path->buf, normalized_objdir))
306 return 0;
307
308 return 1;
309}
310
ddd5d056
JH
311/*
312 * Prepare alternate object database registry.
d5a63b99
JH
313 *
314 * The variable alt_odb_list points at the list of struct
315 * alternate_object_database. The elements on this list come from
316 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
317 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
1494e038
JH
318 * whose contents is similar to that environment variable but can be
319 * LF separated. Its base points at a statically allocated buffer that
d5a63b99
JH
320 * contains "/the/directory/corresponding/to/.git/objects/...", while
321 * its name points just after the slash at the end of ".git/objects/"
322 * in the example above, and has enough space to hold 40-byte hex
323 * SHA1, an extra slash for the first level indirection, and the
324 * terminating NUL.
ddd5d056 325 */
2456990d 326static void read_info_alternates(const char * relative_base, int depth);
539e7506
EK
327static int link_alt_odb_entry(const char *entry, const char *relative_base,
328 int depth, const char *normalized_objdir)
ace1534d 329{
c2f493a4 330 struct alternate_object_database *ent;
5bdf0a84 331 struct strbuf pathbuf = STRBUF_INIT;
d5a63b99 332
85dadc38 333 if (!is_absolute_path(entry) && relative_base) {
4ac9006f 334 strbuf_realpath(&pathbuf, relative_base, 1);
5bdf0a84 335 strbuf_addch(&pathbuf, '/');
c2f493a4 336 }
6eac50d8 337 strbuf_addstr(&pathbuf, entry);
c2f493a4 338
37a95862 339 if (strbuf_normalize_path(&pathbuf) < 0 && relative_base) {
670c359d
JK
340 error("unable to normalize alternate object path: %s",
341 pathbuf.buf);
342 strbuf_release(&pathbuf);
343 return -1;
344 }
5bdf0a84
HW
345
346 /*
347 * The trailing slash after the directory name is given by
348 * this function at the end. Remove duplicates.
349 */
4ea82473
JK
350 while (pathbuf.len && pathbuf.buf[pathbuf.len - 1] == '/')
351 strbuf_setlen(&pathbuf, pathbuf.len - 1);
5bdf0a84 352
4ea82473
JK
353 if (!alt_odb_usable(&pathbuf, normalized_objdir)) {
354 strbuf_release(&pathbuf);
c2f493a4
MW
355 return -1;
356 }
357
7f0fa2c0 358 ent = alloc_alt_odb(pathbuf.buf);
c2f493a4
MW
359
360 /* add the alternate entry */
361 *alt_odb_tail = ent;
362 alt_odb_tail = &(ent->next);
363 ent->next = NULL;
364
365 /* recursively add alternates */
4ea82473 366 read_info_alternates(pathbuf.buf, depth + 1);
c2f493a4 367
4ea82473 368 strbuf_release(&pathbuf);
c2f493a4
MW
369 return 0;
370}
371
cf3c6352
JK
372static const char *parse_alt_odb_entry(const char *string,
373 int sep,
374 struct strbuf *out)
375{
376 const char *end;
377
378 strbuf_reset(out);
379
380 if (*string == '#') {
381 /* comment; consume up to next separator */
382 end = strchrnul(string, sep);
383 } else if (*string == '"' && !unquote_c_style(out, string, &end)) {
384 /*
385 * quoted path; unquote_c_style has copied the
386 * data for us and set "end". Broken quoting (e.g.,
387 * an entry that doesn't end with a quote) falls
388 * back to the unquoted case below.
389 */
390 } else {
391 /* normal, unquoted path */
392 end = strchrnul(string, sep);
393 strbuf_add(out, string, end - string);
394 }
395
396 if (*end)
397 end++;
398 return end;
399}
400
dc732bd5 401static void link_alt_odb_entries(const char *alt, int sep,
c2f493a4
MW
402 const char *relative_base, int depth)
403{
539e7506 404 struct strbuf objdirbuf = STRBUF_INIT;
cf3c6352 405 struct strbuf entry = STRBUF_INIT;
c2f493a4 406
f28e3668
JK
407 if (!alt || !*alt)
408 return;
409
c2f493a4
MW
410 if (depth > 5) {
411 error("%s: ignoring alternate object stores, nesting too deep.",
412 relative_base);
413 return;
414 }
415
f655651e 416 strbuf_add_absolute_path(&objdirbuf, get_object_directory());
670c359d
JK
417 if (strbuf_normalize_path(&objdirbuf) < 0)
418 die("unable to normalize object directory: %s",
419 objdirbuf.buf);
539e7506 420
cf3c6352
JK
421 while (*alt) {
422 alt = parse_alt_odb_entry(alt, sep, &entry);
423 if (!entry.len)
9577e7e3 424 continue;
cf3c6352 425 link_alt_odb_entry(entry.buf, relative_base, depth, objdirbuf.buf);
9577e7e3 426 }
cf3c6352 427 strbuf_release(&entry);
539e7506 428 strbuf_release(&objdirbuf);
d5a63b99
JH
429}
430
2456990d 431static void read_info_alternates(const char * relative_base, int depth)
d5a63b99 432{
5015f01c 433 char *path;
dc732bd5 434 struct strbuf buf = STRBUF_INIT;
d5a63b99 435
5015f01c 436 path = xstrfmt("%s/info/alternates", relative_base);
dc732bd5 437 if (strbuf_read_file(&buf, path, 1024) < 0) {
f0f7bebe 438 warn_on_fopen_errors(path);
dc732bd5 439 free(path);
9a217f2a 440 return;
ace1534d 441 }
d5a63b99 442
dc732bd5
JK
443 link_alt_odb_entries(buf.buf, '\n', relative_base, depth);
444 strbuf_release(&buf);
445 free(path);
ace1534d
JH
446}
447
7f0fa2c0
JK
448struct alternate_object_database *alloc_alt_odb(const char *dir)
449{
450 struct alternate_object_database *ent;
7f0fa2c0 451
597f9134 452 FLEX_ALLOC_STR(ent, path, dir);
38dbe5f0
JK
453 strbuf_init(&ent->scratch, 0);
454 strbuf_addf(&ent->scratch, "%s/", dir);
455 ent->base_len = ent->scratch.len;
7f0fa2c0
JK
456
457 return ent;
458}
459
bef70b22
DB
460void add_to_alternates_file(const char *reference)
461{
462 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
77b9b1d1
JK
463 char *alts = git_pathdup("objects/info/alternates");
464 FILE *in, *out;
465
466 hold_lock_file_for_update(lock, alts, LOCK_DIE_ON_ERROR);
467 out = fdopen_lock_file(lock, "w");
468 if (!out)
469 die_errno("unable to fdopen alternates lockfile");
470
471 in = fopen(alts, "r");
472 if (in) {
473 struct strbuf line = STRBUF_INIT;
474 int found = 0;
475
3f163962 476 while (strbuf_getline(&line, in) != EOF) {
77b9b1d1
JK
477 if (!strcmp(reference, line.buf)) {
478 found = 1;
479 break;
480 }
481 fprintf_or_die(out, "%s\n", line.buf);
482 }
483
484 strbuf_release(&line);
485 fclose(in);
486
487 if (found) {
488 rollback_lock_file(lock);
489 lock = NULL;
490 }
491 }
492 else if (errno != ENOENT)
493 die_errno("unable to read alternates file");
494
495 if (lock) {
496 fprintf_or_die(out, "%s\n", reference);
497 if (commit_lock_file(lock))
498 die_errno("unable to move new alternates file into place");
499 if (alt_odb_tail)
dc732bd5 500 link_alt_odb_entries(reference, '\n', NULL, 0);
77b9b1d1
JK
501 }
502 free(alts);
bef70b22
DB
503}
504
a5b34d21
JK
505void add_to_alternates_memory(const char *reference)
506{
507 /*
508 * Make sure alternates are initialized, or else our entry may be
509 * overwritten when they are.
510 */
511 prepare_alt_odb();
512
dc732bd5 513 link_alt_odb_entries(reference, '\n', NULL, 0);
a5b34d21
JK
514}
515
9eeea7d2
SB
516/*
517 * Compute the exact path an alternate is at and returns it. In case of
518 * error NULL is returned and the human readable error is added to `err`
519 * `path` may be relative and should point to $GITDIR.
520 * `err` must not be null.
521 */
522char *compute_alternate_path(const char *path, struct strbuf *err)
523{
524 char *ref_git = NULL;
525 const char *repo, *ref_git_s;
526 int seen_error = 0;
527
528 ref_git_s = real_path_if_valid(path);
529 if (!ref_git_s) {
530 seen_error = 1;
531 strbuf_addf(err, _("path '%s' does not exist"), path);
532 goto out;
533 } else
534 /*
535 * Beware: read_gitfile(), real_path() and mkpath()
536 * return static buffer
537 */
538 ref_git = xstrdup(ref_git_s);
539
540 repo = read_gitfile(ref_git);
541 if (!repo)
542 repo = read_gitfile(mkpath("%s/.git", ref_git));
543 if (repo) {
544 free(ref_git);
545 ref_git = xstrdup(repo);
546 }
547
548 if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
549 char *ref_git_git = mkpathdup("%s/.git", ref_git);
550 free(ref_git);
551 ref_git = ref_git_git;
552 } else if (!is_directory(mkpath("%s/objects", ref_git))) {
553 struct strbuf sb = STRBUF_INIT;
554 seen_error = 1;
555 if (get_common_dir(&sb, ref_git)) {
556 strbuf_addf(err,
557 _("reference repository '%s' as a linked "
558 "checkout is not supported yet."),
559 path);
560 goto out;
561 }
562
563 strbuf_addf(err, _("reference repository '%s' is not a "
564 "local repository."), path);
565 goto out;
566 }
567
568 if (!access(mkpath("%s/shallow", ref_git), F_OK)) {
569 strbuf_addf(err, _("reference repository '%s' is shallow"),
570 path);
571 seen_error = 1;
572 goto out;
573 }
574
575 if (!access(mkpath("%s/info/grafts", ref_git), F_OK)) {
576 strbuf_addf(err,
577 _("reference repository '%s' is grafted"),
578 path);
579 seen_error = 1;
580 goto out;
581 }
582
583out:
584 if (seen_error) {
6a83d902 585 FREE_AND_NULL(ref_git);
9eeea7d2
SB
586 }
587
588 return ref_git;
589}
590
fe1b2268 591int foreach_alt_odb(alt_odb_fn fn, void *cb)
d79796bc
JH
592{
593 struct alternate_object_database *ent;
fe1b2268 594 int r = 0;
d79796bc
JH
595
596 prepare_alt_odb();
fe1b2268
JK
597 for (ent = alt_odb_list; ent; ent = ent->next) {
598 r = fn(ent, cb);
599 if (r)
600 break;
601 }
602 return r;
d79796bc
JH
603}
604
c2f493a4
MW
605void prepare_alt_odb(void)
606{
554fe20d 607 const char *alt;
c2f493a4 608
7dc24aa5
SP
609 if (alt_odb_tail)
610 return;
611
c2f493a4 612 alt = getenv(ALTERNATE_DB_ENVIRONMENT);
c2f493a4 613
c2f493a4 614 alt_odb_tail = &alt_odb_list;
dc732bd5 615 link_alt_odb_entries(alt, PATH_SEP, NULL, 0);
c2f493a4
MW
616
617 read_info_alternates(get_object_directory(), 0);
618}
619
3096b2ec 620/* Returns 1 if we have successfully freshened the file, 0 otherwise. */
33d4221c 621static int freshen_file(const char *fn)
ace1534d 622{
33d4221c
JK
623 struct utimbuf t;
624 t.actime = t.modtime = time(NULL);
625 return !utime(fn, &t);
0f4dc14a 626}
ace1534d 627
3096b2ec
JK
628/*
629 * All of the check_and_freshen functions return 1 if the file exists and was
630 * freshened (if freshening was requested), 0 otherwise. If they return
631 * 0, you should not assume that it is safe to skip a write of the object (it
632 * either does not exist on disk, or has a stale mtime and may be subject to
633 * pruning).
634 */
6a5e6f5e 635int check_and_freshen_file(const char *fn, int freshen)
33d4221c
JK
636{
637 if (access(fn, F_OK))
638 return 0;
3096b2ec 639 if (freshen && !freshen_file(fn))
33d4221c
JK
640 return 0;
641 return 1;
642}
643
644static int check_and_freshen_local(const unsigned char *sha1, int freshen)
645{
646 return check_and_freshen_file(sha1_file_name(sha1), freshen);
647}
648
649static int check_and_freshen_nonlocal(const unsigned char *sha1, int freshen)
0f4dc14a
BC
650{
651 struct alternate_object_database *alt;
9a217f2a 652 prepare_alt_odb();
d5a63b99 653 for (alt = alt_odb_list; alt; alt = alt->next) {
29ec6af2
JK
654 const char *path = alt_sha1_path(alt, sha1);
655 if (check_and_freshen_file(path, freshen))
c529d75a 656 return 1;
ace1534d 657 }
c529d75a 658 return 0;
ace1534d
JH
659}
660
33d4221c
JK
661static int check_and_freshen(const unsigned char *sha1, int freshen)
662{
663 return check_and_freshen_local(sha1, freshen) ||
664 check_and_freshen_nonlocal(sha1, freshen);
665}
666
667int has_loose_object_nonlocal(const unsigned char *sha1)
668{
669 return check_and_freshen_nonlocal(sha1, 0);
670}
671
0f4dc14a
BC
672static int has_loose_object(const unsigned char *sha1)
673{
33d4221c 674 return check_and_freshen(sha1, 0);
0f4dc14a
BC
675}
676
02710228
SP
677static void mmap_limit_check(size_t length)
678{
679 static size_t limit = 0;
680 if (!limit) {
681 limit = git_env_ulong("GIT_MMAP_LIMIT", 0);
682 if (!limit)
683 limit = SIZE_MAX;
684 }
685 if (length > limit)
686 die("attempting to mmap %"PRIuMAX" over limit %"PRIuMAX,
687 (uintmax_t)length, (uintmax_t)limit);
688}
689
1570856b
JK
690void *xmmap_gently(void *start, size_t length,
691 int prot, int flags, int fd, off_t offset)
58ecbd5e 692{
02710228
SP
693 void *ret;
694
695 mmap_limit_check(length);
696 ret = mmap(start, length, prot, flags, fd, offset);
58ecbd5e
JN
697 if (ret == MAP_FAILED) {
698 if (!length)
699 return NULL;
7c3ecb32 700 release_pack_memory(length);
58ecbd5e 701 ret = mmap(start, length, prot, flags, fd, offset);
58ecbd5e
JN
702 }
703 return ret;
704}
705
1570856b
JK
706void *xmmap(void *start, size_t length,
707 int prot, int flags, int fd, off_t offset)
708{
709 void *ret = xmmap_gently(start, length, prot, flags, fd, offset);
710 if (ret == MAP_FAILED)
9ca0aaf6 711 die_errno("mmap failed");
1570856b
JK
712 return ret;
713}
714
88d0db55 715/*
090ea126
NTND
716 * With an in-core object data in "map", rehash it to make sure the
717 * object name actually matches "sha1" to detect object corruption.
718 * With "map" == NULL, try reading the object named with "sha1" using
719 * the streaming interface and rehash it to do the same.
88d0db55 720 */
090ea126
NTND
721int check_sha1_signature(const unsigned char *sha1, void *map,
722 unsigned long size, const char *type)
88d0db55 723{
0fcfd160 724 unsigned char real_sha1[20];
090ea126
NTND
725 enum object_type obj_type;
726 struct git_istream *st;
727 git_SHA_CTX c;
728 char hdr[32];
729 int hdrlen;
88d0db55 730
090ea126
NTND
731 if (map) {
732 hash_sha1_file(map, size, type, real_sha1);
733 return hashcmp(sha1, real_sha1) ? -1 : 0;
88d0db55
BC
734 }
735
090ea126
NTND
736 st = open_istream(sha1, &obj_type, &size, NULL);
737 if (!st)
738 return -1;
88d0db55 739
090ea126 740 /* Generate the header */
ef1286d3 741 hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", typename(obj_type), size) + 1;
88d0db55 742
090ea126
NTND
743 /* Sha1.. */
744 git_SHA1_Init(&c);
745 git_SHA1_Update(&c, hdr, hdrlen);
746 for (;;) {
747 char buf[1024 * 16];
748 ssize_t readlen = read_istream(st, buf, sizeof(buf));
1f688557 749
f54fac53
JK
750 if (readlen < 0) {
751 close_istream(st);
752 return -1;
753 }
090ea126
NTND
754 if (!readlen)
755 break;
756 git_SHA1_Update(&c, buf, readlen);
fa5fc15d 757 }
090ea126
NTND
758 git_SHA1_Final(real_sha1, &c);
759 close_istream(st);
a89fccd2 760 return hashcmp(sha1, real_sha1) ? -1 : 0;
fa5fc15d
SP
761}
762
1b8ac5ea 763int git_open_cloexec(const char *name, int flags)
a0788266 764{
1e3001a8
JH
765 int fd;
766 static int o_cloexec = O_CLOEXEC;
a0788266 767
1e3001a8
JH
768 fd = open(name, flags | o_cloexec);
769 if ((o_cloexec & O_CLOEXEC) && fd < 0 && errno == EINVAL) {
cd66ada0 770 /* Try again w/o O_CLOEXEC: the kernel might not support it */
1e3001a8
JH
771 o_cloexec &= ~O_CLOEXEC;
772 fd = open(name, flags | o_cloexec);
491a8dec 773 }
491a8dec 774
9fb9495d 775#if defined(F_GETFD) && defined(F_SETFD) && defined(FD_CLOEXEC)
491a8dec 776 {
1e3001a8 777 static int fd_cloexec = FD_CLOEXEC;
a0788266 778
1e3001a8
JH
779 if (!o_cloexec && 0 <= fd && fd_cloexec) {
780 /* Opened w/o O_CLOEXEC? try with fcntl(2) to add it */
9fb9495d
EW
781 int flags = fcntl(fd, F_GETFD);
782 if (fcntl(fd, F_SETFD, flags | fd_cloexec))
1e3001a8 783 fd_cloexec = 0;
cd66ada0 784 }
44d1c19e 785 }
a0788266 786#endif
1b8ac5ea 787 return fd;
a0788266
JS
788}
789
3cf8b462 790/*
771e7d57
JK
791 * Find "sha1" as a loose object in the local repository or in an alternate.
792 * Returns 0 on success, negative on failure.
793 *
794 * The "path" out-parameter will give the path of the object we found (if any).
795 * Note that it may point to static storage and is only valid until another
796 * call to sha1_file_name(), etc.
3cf8b462 797 */
771e7d57
JK
798static int stat_sha1_file(const unsigned char *sha1, struct stat *st,
799 const char **path)
1f688557 800{
052fe5ea 801 struct alternate_object_database *alt;
d079837e 802
771e7d57
JK
803 *path = sha1_file_name(sha1);
804 if (!lstat(*path, st))
052fe5ea 805 return 0;
c7934306 806
052fe5ea
JK
807 prepare_alt_odb();
808 errno = ENOENT;
809 for (alt = alt_odb_list; alt; alt = alt->next) {
771e7d57
JK
810 *path = alt_sha1_path(alt, sha1);
811 if (!lstat(*path, st))
052fe5ea 812 return 0;
c7934306
SP
813 }
814
3cf8b462
SP
815 return -1;
816}
817
771e7d57
JK
818/*
819 * Like stat_sha1_file(), but actually open the object and return the
820 * descriptor. See the caveats on the "path" parameter above.
821 */
822static int open_sha1_file(const unsigned char *sha1, const char **path)
60bb8b14 823{
44d1c19e 824 int fd;
44d1c19e 825 struct alternate_object_database *alt;
d6c8a05b 826 int most_interesting_errno;
60bb8b14 827
771e7d57
JK
828 *path = sha1_file_name(sha1);
829 fd = git_open(*path);
44d1c19e
LT
830 if (fd >= 0)
831 return fd;
d6c8a05b 832 most_interesting_errno = errno;
03e79c88 833
44d1c19e 834 prepare_alt_odb();
44d1c19e 835 for (alt = alt_odb_list; alt; alt = alt->next) {
771e7d57
JK
836 *path = alt_sha1_path(alt, sha1);
837 fd = git_open(*path);
44d1c19e
LT
838 if (fd >= 0)
839 return fd;
d6c8a05b
JK
840 if (most_interesting_errno == ENOENT)
841 most_interesting_errno = errno;
03e79c88 842 }
d6c8a05b 843 errno = most_interesting_errno;
44d1c19e 844 return -1;
1f688557
JH
845}
846
f6371f92
JK
847/*
848 * Map the loose object at "path" if it is not NULL, or the path found by
849 * searching for a loose object named "sha1".
850 */
851static void *map_sha1_file_1(const char *path,
852 const unsigned char *sha1,
853 unsigned long *size)
27d69a46 854{
0fcfd160 855 void *map;
144bde78 856 int fd;
84dd81c1 857
f6371f92
JK
858 if (path)
859 fd = git_open(path);
8261e1f1 860 else
f6371f92 861 fd = open_sha1_file(sha1, &path);
44d1c19e
LT
862 map = NULL;
863 if (fd >= 0) {
864 struct stat st;
1f688557 865
44d1c19e
LT
866 if (!fstat(fd, &st)) {
867 *size = xsize_t(st.st_size);
33e42de0
MM
868 if (!*size) {
869 /* mmap() is forbidden on empty files */
771e7d57 870 error("object file %s is empty", path);
33e42de0
MM
871 return NULL;
872 }
44d1c19e 873 map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
144bde78 874 }
44d1c19e 875 close(fd);
74e34e1f 876 }
0fcfd160 877 return map;
74e34e1f
NP
878}
879
f6371f92 880void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
068f85e3 881{
f6371f92 882 return map_sha1_file_1(NULL, sha1, size);
068f85e3 883}
884
d21f8426
JH
885static int unpack_sha1_short_header(git_zstream *stream,
886 unsigned char *map, unsigned long mapsize,
887 void *buffer, unsigned long bufsiz)
47fe3f6e 888{
c4483576
LT
889 /* Get the data stream */
890 memset(stream, 0, sizeof(*stream));
891 stream->next_in = map;
892 stream->avail_in = mapsize;
893 stream->next_out = buffer;
93821bd9 894 stream->avail_out = bufsiz;
47fe3f6e 895
39c68542 896 git_inflate_init(stream);
cc5c54e7 897 return git_inflate(stream, 0);
9a217f2a
JH
898}
899
d21f8426
JH
900int unpack_sha1_header(git_zstream *stream,
901 unsigned char *map, unsigned long mapsize,
902 void *buffer, unsigned long bufsiz)
1f688557 903{
d21f8426
JH
904 int status = unpack_sha1_short_header(stream, map, mapsize,
905 buffer, bufsiz);
42873078 906
d21f8426
JH
907 if (status < Z_OK)
908 return status;
628522ec 909
d21f8426
JH
910 /* Make sure we have the terminating NUL */
911 if (!memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
912 return -1;
1f688557
JH
913 return 0;
914}
915
46f03448
KN
916static int unpack_sha1_header_to_strbuf(git_zstream *stream, unsigned char *map,
917 unsigned long mapsize, void *buffer,
918 unsigned long bufsiz, struct strbuf *header)
d131b7af 919{
46f03448
KN
920 int status;
921
d21f8426
JH
922 status = unpack_sha1_short_header(stream, map, mapsize, buffer, bufsiz);
923 if (status < Z_OK)
924 return -1;
d131b7af 925
46f03448
KN
926 /*
927 * Check if entire header is unpacked in the first iteration.
d131b7af 928 */
46f03448
KN
929 if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
930 return 0;
d131b7af 931
46f03448
KN
932 /*
933 * buffer[0..bufsiz] was not large enough. Copy the partial
934 * result out to header, and then append the result of further
935 * reading the stream.
936 */
937 strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
938 stream->next_out = buffer;
939 stream->avail_out = bufsiz;
d131b7af 940
46f03448
KN
941 do {
942 status = git_inflate(stream, 0);
943 strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
944 if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
945 return 0;
946 stream->next_out = buffer;
947 stream->avail_out = bufsiz;
948 } while (status != Z_STREAM_END);
949 return -1;
d131b7af
SP
950}
951
ef49a7a0 952static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
95099731 953{
5180cacc 954 int bytes = strlen(buffer) + 1;
3aee68aa 955 unsigned char *buf = xmallocz(size);
93821bd9 956 unsigned long n;
7efbff75 957 int status = Z_OK;
95099731 958
93821bd9
LT
959 n = stream->total_out - bytes;
960 if (n > size)
961 n = size;
962 memcpy(buf, (char *) buffer + bytes, n);
963 bytes = n;
456cdf6e
LT
964 if (bytes <= size) {
965 /*
966 * The above condition must be (bytes <= size), not
967 * (bytes < size). In other words, even though we
ccf5ace0 968 * expect no more output and set avail_out to zero,
456cdf6e
LT
969 * the input zlib stream may have bytes that express
970 * "this concludes the stream", and we *do* want to
971 * eat that input.
972 *
973 * Otherwise we would not be able to test that we
974 * consumed all the input to reach the expected size;
975 * we also want to check that zlib tells us that all
976 * went well with status == Z_STREAM_END at the end.
977 */
5180cacc
LT
978 stream->next_out = buf + bytes;
979 stream->avail_out = size - bytes;
7efbff75 980 while (status == Z_OK)
39c68542 981 status = git_inflate(stream, Z_FINISH);
5180cacc 982 }
456cdf6e 983 if (status == Z_STREAM_END && !stream->avail_in) {
39c68542 984 git_inflate_end(stream);
7efbff75 985 return buf;
95099731
NTND
986 }
987
7efbff75
JH
988 if (status < 0)
989 error("corrupt loose object '%s'", sha1_to_hex(sha1));
990 else if (stream->avail_in)
991 error("garbage at end of loose object '%s'",
992 sha1_to_hex(sha1));
993 free(buf);
994 return NULL;
95099731
NTND
995}
996
d40d535b 997/*
5180cacc
LT
998 * We used to just use "sscanf()", but that's actually way
999 * too permissive for what we want to check. So do an anal
1000 * object header parse by hand.
d40d535b 1001 */
46f03448
KN
1002static int parse_sha1_header_extended(const char *hdr, struct object_info *oi,
1003 unsigned int flags)
1f688557 1004{
46f03448 1005 const char *type_buf = hdr;
5180cacc 1006 unsigned long size;
46f03448 1007 int type, type_len = 0;
43057304 1008
5180cacc 1009 /*
46f03448 1010 * The type can be of any size but is followed by
21666f1a 1011 * a space.
5180cacc 1012 */
5180cacc
LT
1013 for (;;) {
1014 char c = *hdr++;
d21f8426
JH
1015 if (!c)
1016 return -1;
5180cacc
LT
1017 if (c == ' ')
1018 break;
46f03448 1019 type_len++;
5180cacc 1020 }
1f688557 1021
46f03448
KN
1022 type = type_from_string_gently(type_buf, type_len, 1);
1023 if (oi->typename)
1024 strbuf_add(oi->typename, type_buf, type_len);
1025 /*
1026 * Set type to 0 if its an unknown object and
2e3a16b2 1027 * we're obtaining the type using '--allow-unknown-type'
46f03448
KN
1028 * option.
1029 */
19fc5e84 1030 if ((flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE) && (type < 0))
46f03448
KN
1031 type = 0;
1032 else if (type < 0)
1033 die("invalid object type");
1034 if (oi->typep)
1035 *oi->typep = type;
5180cacc
LT
1036
1037 /*
1038 * The length must follow immediately, and be in canonical
1039 * decimal format (ie "010" is not valid).
1040 */
1041 size = *hdr++ - '0';
1042 if (size > 9)
1043 return -1;
1044 if (size) {
1045 for (;;) {
1046 unsigned long c = *hdr - '0';
1047 if (c > 9)
1048 break;
1049 hdr++;
1050 size = size * 10 + c;
1b1005d1 1051 }
c01f51cc 1052 }
46f03448
KN
1053
1054 if (oi->sizep)
1055 *oi->sizep = size;
5180cacc
LT
1056
1057 /*
1058 * The length must be followed by a zero byte
1059 */
46f03448 1060 return *hdr ? -1 : type;
1f688557
JH
1061}
1062
46f03448 1063int parse_sha1_header(const char *hdr, unsigned long *sizep)
bf592c50 1064{
27b5c1a0 1065 struct object_info oi = OBJECT_INFO_INIT;
21666f1a 1066
46f03448 1067 oi.sizep = sizep;
1f0c0d36 1068 return parse_sha1_header_extended(hdr, &oi, 0);
bf592c50
DB
1069}
1070
052fe5ea 1071static int sha1_loose_object_info(const unsigned char *sha1,
46f03448
KN
1072 struct object_info *oi,
1073 int flags)
65c2e0c3 1074{
46f03448
KN
1075 int status = 0;
1076 unsigned long mapsize;
65c2e0c3 1077 void *map;
ef49a7a0 1078 git_zstream stream;
d65a16f6 1079 char hdr[32];
46f03448 1080 struct strbuf hdrbuf = STRBUF_INIT;
c84a1f3e 1081 unsigned long size_scratch;
65c2e0c3 1082
5d642e75
JK
1083 if (oi->delta_base_sha1)
1084 hashclr(oi->delta_base_sha1);
1085
052fe5ea
JK
1086 /*
1087 * If we don't care about type or size, then we don't
4ef8d1dd
JH
1088 * need to look inside the object at all. Note that we
1089 * do not optimize out the stat call, even if the
1090 * caller doesn't care about the disk-size, since our
1091 * return value implicitly indicates whether the
1092 * object even exists.
052fe5ea 1093 */
c84a1f3e 1094 if (!oi->typep && !oi->typename && !oi->sizep && !oi->contentp) {
771e7d57 1095 const char *path;
4ef8d1dd 1096 struct stat st;
771e7d57 1097 if (stat_sha1_file(sha1, &st, &path) < 0)
4ef8d1dd
JH
1098 return -1;
1099 if (oi->disk_sizep)
23c339c0 1100 *oi->disk_sizep = st.st_size;
052fe5ea
JK
1101 return 0;
1102 }
1103
bb6b8e4f 1104 map = map_sha1_file(sha1, &mapsize);
f0df4ed5 1105 if (!map)
dbea72a8 1106 return -1;
c84a1f3e
JT
1107
1108 if (!oi->sizep)
1109 oi->sizep = &size_scratch;
1110
23c339c0
JK
1111 if (oi->disk_sizep)
1112 *oi->disk_sizep = mapsize;
19fc5e84 1113 if ((flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE)) {
46f03448
KN
1114 if (unpack_sha1_header_to_strbuf(&stream, map, mapsize, hdr, sizeof(hdr), &hdrbuf) < 0)
1115 status = error("unable to unpack %s header with --allow-unknown-type",
1116 sha1_to_hex(sha1));
1117 } else if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
36e4d74a
JH
1118 status = error("unable to unpack %s header",
1119 sha1_to_hex(sha1));
46f03448
KN
1120 if (status < 0)
1121 ; /* Do nothing */
1122 else if (hdrbuf.len) {
1123 if ((status = parse_sha1_header_extended(hdrbuf.buf, oi, flags)) < 0)
1124 status = error("unable to parse %s header with --allow-unknown-type",
1125 sha1_to_hex(sha1));
1126 } else if ((status = parse_sha1_header_extended(hdr, oi, flags)) < 0)
36e4d74a 1127 status = error("unable to parse %s header", sha1_to_hex(sha1));
c84a1f3e 1128
b3ea7dd3 1129 if (status >= 0 && oi->contentp) {
c84a1f3e
JT
1130 *oi->contentp = unpack_sha1_rest(&stream, hdr,
1131 *oi->sizep, sha1);
b3ea7dd3
JK
1132 if (!*oi->contentp) {
1133 git_inflate_end(&stream);
1134 status = -1;
1135 }
1136 } else
c84a1f3e
JT
1137 git_inflate_end(&stream);
1138
65c2e0c3 1139 munmap(map, mapsize);
46f03448 1140 if (status && oi->typep)
23c339c0 1141 *oi->typep = status;
c84a1f3e
JT
1142 if (oi->sizep == &size_scratch)
1143 oi->sizep = NULL;
46f03448 1144 strbuf_release(&hdrbuf);
3ab0fb06 1145 oi->whence = OI_LOOSE;
93cff9a9 1146 return (status < 0) ? status : 0;
65c2e0c3
JH
1147}
1148
de7b5d62 1149int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi, unsigned flags)
f0df4ed5 1150{
cd585e2a 1151 static struct object_info blank_oi = OBJECT_INFO_INIT;
f0df4ed5 1152 struct pack_entry e;
5b086407 1153 int rtype;
1f0c0d36
JT
1154 const unsigned char *real = (flags & OBJECT_INFO_LOOKUP_REPLACE) ?
1155 lookup_replace_object(sha1) :
1156 sha1;
f0df4ed5 1157
cd585e2a
JT
1158 if (!oi)
1159 oi = &blank_oi;
1160
dfdd4afc
JT
1161 if (!(flags & OBJECT_INFO_SKIP_CACHED)) {
1162 struct cached_object *co = find_cached_object(real);
1163 if (co) {
1164 if (oi->typep)
1165 *(oi->typep) = co->type;
1166 if (oi->sizep)
1167 *(oi->sizep) = co->size;
1168 if (oi->disk_sizep)
1169 *(oi->disk_sizep) = 0;
1170 if (oi->delta_base_sha1)
1171 hashclr(oi->delta_base_sha1);
1172 if (oi->typename)
1173 strbuf_addstr(oi->typename, typename(co->type));
1174 if (oi->contentp)
1175 *oi->contentp = xmemdupz(co->buf, co->size);
1176 oi->whence = OI_CACHED;
1177 return 0;
1178 }
c4d9986f
NTND
1179 }
1180
1f7117ef 1181 if (!find_pack_entry(real, &e)) {
ddd63e64 1182 /* Most likely it's a loose object. */
3ab0fb06 1183 if (!sha1_loose_object_info(real, oi, flags))
5b086407 1184 return 0;
ddd63e64
SG
1185
1186 /* Not a loose object; someone else may have just packed it. */
dfdd4afc 1187 if (flags & OBJECT_INFO_QUICK) {
052fe5ea 1188 return -1;
dfdd4afc
JT
1189 } else {
1190 reprepare_packed_git();
1191 if (!find_pack_entry(real, &e))
1192 return -1;
1193 }
f0df4ed5 1194 }
3d77d877 1195
cd585e2a
JT
1196 if (oi == &blank_oi)
1197 /*
1198 * We know that the caller doesn't actually need the
1199 * information below, so return early.
1200 */
1201 return 0;
46f03448 1202
23c339c0 1203 rtype = packed_object_info(e.p, e.offset, oi);
412916ee 1204 if (rtype < 0) {
1f7117ef
CC
1205 mark_bad_packed_object(e.p, real);
1206 return sha1_object_info_extended(real, oi, 0);
3ab0fb06 1207 } else if (oi->whence == OI_PACKED) {
9a490590
JH
1208 oi->u.packed.offset = e.offset;
1209 oi->u.packed.pack = e.p;
1210 oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
1211 rtype == OBJ_OFS_DELTA);
3d77d877
NP
1212 }
1213
5b086407 1214 return 0;
f0df4ed5
JS
1215}
1216
3fc0dca9 1217/* returns enum object_type or negative */
9a490590
JH
1218int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
1219{
5b086407 1220 enum object_type type;
27b5c1a0 1221 struct object_info oi = OBJECT_INFO_INIT;
9a490590 1222
5b086407 1223 oi.typep = &type;
9a490590 1224 oi.sizep = sizep;
1f0c0d36
JT
1225 if (sha1_object_info_extended(sha1, &oi,
1226 OBJECT_INFO_LOOKUP_REPLACE) < 0)
5b086407
JK
1227 return -1;
1228 return type;
9a490590
JH
1229}
1230
f1d8130b
JT
1231static void *read_object(const unsigned char *sha1, enum object_type *type,
1232 unsigned long *size)
1233{
1234 struct object_info oi = OBJECT_INFO_INIT;
1235 void *content;
1236 oi.typep = type;
1237 oi.sizep = size;
1238 oi.contentp = &content;
1239
1240 if (sha1_object_info_extended(sha1, &oi, 0) < 0)
1241 return NULL;
1242 return content;
1243}
1244
21666f1a
NP
1245int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
1246 unsigned char *sha1)
d66b37bb
JH
1247{
1248 struct cached_object *co;
1249
21666f1a 1250 hash_sha1_file(buf, len, typename(type), sha1);
d66b37bb
JH
1251 if (has_sha1_file(sha1) || find_cached_object(sha1))
1252 return 0;
c7353967 1253 ALLOC_GROW(cached_objects, cached_object_nr + 1, cached_object_alloc);
d66b37bb
JH
1254 co = &cached_objects[cached_object_nr++];
1255 co->size = len;
21666f1a 1256 co->type = type;
efa13f7b
JH
1257 co->buf = xmalloc(len);
1258 memcpy(co->buf, buf, len);
d66b37bb
JH
1259 hashcpy(co->sha1, sha1);
1260 return 0;
1261}
1262
b6c4cecc
JH
1263/*
1264 * This function dies on corrupt objects; the callers who want to
1265 * deal with them should arrange to call read_object() and give error
1266 * messages themselves.
1267 */
5bf29b95
JH
1268void *read_sha1_file_extended(const unsigned char *sha1,
1269 enum object_type *type,
1270 unsigned long *size,
1f0c0d36 1271 int lookup_replace)
ac939109 1272{
3ba7a065 1273 void *data;
b6c4cecc 1274 const struct packed_git *p;
771e7d57
JK
1275 const char *path;
1276 struct stat st;
1f0c0d36
JT
1277 const unsigned char *repl = lookup_replace ? lookup_replace_object(sha1)
1278 : sha1;
b6c4cecc 1279
3ba7a065
JH
1280 errno = 0;
1281 data = read_object(repl, type, size);
4bbf5a26 1282 if (data)
b6c4cecc 1283 return data;
68095570 1284
25f3af3f 1285 if (errno && errno != ENOENT)
3ba7a065
JH
1286 die_errno("failed to read object %s", sha1_to_hex(sha1));
1287
68095570 1288 /* die if we replaced an object with one that does not exist */
b6c4cecc 1289 if (repl != sha1)
68095570
CC
1290 die("replacement %s not found for %s",
1291 sha1_to_hex(repl), sha1_to_hex(sha1));
1292
771e7d57 1293 if (!stat_sha1_file(repl, &st, &path))
b6c4cecc
JH
1294 die("loose object %s (stored in %s) is corrupt",
1295 sha1_to_hex(repl), path);
68095570 1296
b6c4cecc
JH
1297 if ((p = has_packed_and_bad(repl)) != NULL)
1298 die("packed object %s (stored in %s) is corrupt",
1299 sha1_to_hex(repl), p->pack_name);
f5552aee 1300
b6c4cecc 1301 return NULL;
ac939109
NP
1302}
1303
40469ee9 1304void *read_object_with_reference(const unsigned char *sha1,
21666f1a 1305 const char *required_type_name,
40469ee9
JH
1306 unsigned long *size,
1307 unsigned char *actual_sha1_return)
f4913f91 1308{
21666f1a 1309 enum object_type type, required_type;
f4913f91
JH
1310 void *buffer;
1311 unsigned long isize;
40469ee9 1312 unsigned char actual_sha1[20];
f4913f91 1313
21666f1a 1314 required_type = type_from_string(required_type_name);
e702496e 1315 hashcpy(actual_sha1, sha1);
40469ee9
JH
1316 while (1) {
1317 int ref_length = -1;
1318 const char *ref_type = NULL;
f4913f91 1319
21666f1a 1320 buffer = read_sha1_file(actual_sha1, &type, &isize);
40469ee9
JH
1321 if (!buffer)
1322 return NULL;
21666f1a 1323 if (type == required_type) {
40469ee9
JH
1324 *size = isize;
1325 if (actual_sha1_return)
e702496e 1326 hashcpy(actual_sha1_return, actual_sha1);
40469ee9
JH
1327 return buffer;
1328 }
1329 /* Handle references */
21666f1a 1330 else if (type == OBJ_COMMIT)
40469ee9 1331 ref_type = "tree ";
21666f1a 1332 else if (type == OBJ_TAG)
40469ee9
JH
1333 ref_type = "object ";
1334 else {
1335 free(buffer);
1336 return NULL;
1337 }
1338 ref_length = strlen(ref_type);
f4913f91 1339
50974ec9
MK
1340 if (ref_length + 40 > isize ||
1341 memcmp(buffer, ref_type, ref_length) ||
1d7f171c 1342 get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
40469ee9
JH
1343 free(buffer);
1344 return NULL;
1345 }
1cf58e72 1346 free(buffer);
40469ee9
JH
1347 /* Now we have the ID of the referred-to object in
1348 * actual_sha1. Check again. */
f4913f91 1349 }
f4913f91
JH
1350}
1351
ce9fbf16 1352static void write_sha1_file_prepare(const void *buf, unsigned long len,
972a9155 1353 const char *type, unsigned char *sha1,
d65a16f6 1354 char *hdr, int *hdrlen)
d410c0f5 1355{
9126f009 1356 git_SHA_CTX c;
d410c0f5
JH
1357
1358 /* Generate the header */
ef1286d3 1359 *hdrlen = xsnprintf(hdr, *hdrlen, "%s %lu", type, len)+1;
d410c0f5
JH
1360
1361 /* Sha1.. */
9126f009
NP
1362 git_SHA1_Init(&c);
1363 git_SHA1_Update(&c, hdr, *hdrlen);
1364 git_SHA1_Update(&c, buf, len);
1365 git_SHA1_Final(sha1, &c);
d410c0f5
JH
1366}
1367
230f1322 1368/*
5a688fe4 1369 * Move the just written object into its final resting place.
230f1322 1370 */
cb5add58 1371int finalize_object_file(const char *tmpfile, const char *filename)
230f1322 1372{
e32c0a9c 1373 int ret = 0;
5a688fe4 1374
348df166 1375 if (object_creation_mode == OBJECT_CREATION_USES_RENAMES)
be66a6c4
JS
1376 goto try_rename;
1377 else if (link(tmpfile, filename))
e32c0a9c 1378 ret = errno;
7ebb6fca
LT
1379
1380 /*
1381 * Coda hack - coda doesn't like cross-directory links,
1382 * so we fall back to a rename, which will mean that it
1383 * won't be able to check collisions, but that's not a
1384 * big deal.
1385 *
1386 * The same holds for FAT formatted media.
1387 *
3be1f18e 1388 * When this succeeds, we just return. We have nothing
7ebb6fca
LT
1389 * left to unlink.
1390 */
1391 if (ret && ret != EEXIST) {
be66a6c4 1392 try_rename:
7ebb6fca 1393 if (!rename(tmpfile, filename))
3be1f18e 1394 goto out;
9e48b389 1395 ret = errno;
230f1322 1396 }
691f1a28 1397 unlink_or_warn(tmpfile);
230f1322
LT
1398 if (ret) {
1399 if (ret != EEXIST) {
7616c6ca 1400 return error_errno("unable to write sha1 filename %s", filename);
230f1322
LT
1401 }
1402 /* FIXME!!! Collision check here ? */
1403 }
1404
3be1f18e 1405out:
5256b006 1406 if (adjust_shared_perm(filename))
5a688fe4 1407 return error("unable to set permission to '%s'", filename);
230f1322
LT
1408 return 0;
1409}
1410
4d548150
LT
1411static int write_buffer(int fd, const void *buf, size_t len)
1412{
d34cf19b 1413 if (write_in_full(fd, buf, len) < 0)
7616c6ca 1414 return error_errno("file write error");
4d548150
LT
1415 return 0;
1416}
1417
ce9fbf16 1418int hash_sha1_file(const void *buf, unsigned long len, const char *type,
abdc3fc8
RS
1419 unsigned char *sha1)
1420{
d65a16f6 1421 char hdr[32];
ef1286d3 1422 int hdrlen = sizeof(hdr);
abdc3fc8
RS
1423 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
1424 return 0;
1425}
1426
e9039dd3
LT
1427/* Finalize a file on disk, and close it. */
1428static void close_sha1_file(int fd)
1429{
aafe9fba
LT
1430 if (fsync_object_files)
1431 fsync_or_die(fd, "sha1 file");
e9039dd3 1432 if (close(fd) != 0)
d824cbba 1433 die_errno("error when closing sha1 file");
e9039dd3
LT
1434}
1435
5723fe7e
LT
1436/* Size of directory component, including the ending '/' */
1437static inline int directory_size(const char *filename)
1438{
1439 const char *s = strrchr(filename, '/');
1440 if (!s)
1441 return 0;
1442 return s - filename + 1;
1443}
1444
1445/*
1446 * This creates a temporary file in the same directory as the final
1447 * 'filename'
1448 *
1449 * We want to avoid cross-directory filename renames, because those
1450 * can have problems on various filesystems (FAT, NFS, Coda).
1451 */
d4b3d11a 1452static int create_tmpfile(struct strbuf *tmp, const char *filename)
5723fe7e
LT
1453{
1454 int fd, dirlen = directory_size(filename);
1455
d4b3d11a
JK
1456 strbuf_reset(tmp);
1457 strbuf_add(tmp, filename, dirlen);
1458 strbuf_addstr(tmp, "tmp_obj_XXXXXX");
1459 fd = git_mkstemp_mode(tmp->buf, 0444);
cbacbf4e 1460 if (fd < 0 && dirlen && errno == ENOENT) {
d4b3d11a
JK
1461 /*
1462 * Make sure the directory exists; note that the contents
1463 * of the buffer are undefined after mkstemp returns an
1464 * error, so we have to rewrite the whole buffer from
1465 * scratch.
1466 */
1467 strbuf_reset(tmp);
1468 strbuf_add(tmp, filename, dirlen - 1);
1469 if (mkdir(tmp->buf, 0777) && errno != EEXIST)
b2476a60 1470 return -1;
d4b3d11a 1471 if (adjust_shared_perm(tmp->buf))
5723fe7e
LT
1472 return -1;
1473
1474 /* Try again */
d4b3d11a
JK
1475 strbuf_addstr(tmp, "/tmp_obj_XXXXXX");
1476 fd = git_mkstemp_mode(tmp->buf, 0444);
5723fe7e
LT
1477 }
1478 return fd;
1479}
1480
bbac7311 1481static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
c00e657d 1482 const void *buf, unsigned long len, time_t mtime)
0fcfd160 1483{
915308b1 1484 int fd, ret;
9892beba 1485 unsigned char compressed[4096];
ef49a7a0 1486 git_zstream stream;
748af44c
NP
1487 git_SHA_CTX c;
1488 unsigned char parano_sha1[20];
d4b3d11a 1489 static struct strbuf tmp_file = STRBUF_INIT;
30d6c6ea 1490 const char *filename = sha1_file_name(sha1);
a44c9a5e 1491
d4b3d11a 1492 fd = create_tmpfile(&tmp_file, filename);
aac17941 1493 if (fd < 0) {
35243577 1494 if (errno == EACCES)
82247e9b 1495 return error("insufficient permission for adding an object to repository database %s", get_object_directory());
916d081b 1496 else
7616c6ca 1497 return error_errno("unable to create temporary file");
aac17941
LT
1498 }
1499
0fcfd160 1500 /* Set it up */
55bb5c91 1501 git_deflate_init(&stream, zlib_compression_level);
0fcfd160 1502 stream.next_out = compressed;
9892beba 1503 stream.avail_out = sizeof(compressed);
748af44c 1504 git_SHA1_Init(&c);
a44c9a5e
LT
1505
1506 /* First header.. */
d65a16f6 1507 stream.next_in = (unsigned char *)hdr;
a44c9a5e 1508 stream.avail_in = hdrlen;
55bb5c91
JH
1509 while (git_deflate(&stream, 0) == Z_OK)
1510 ; /* nothing */
748af44c 1511 git_SHA1_Update(&c, hdr, hdrlen);
a44c9a5e
LT
1512
1513 /* Then the data itself.. */
c00e657d 1514 stream.next_in = (void *)buf;
a44c9a5e 1515 stream.avail_in = len;
9892beba 1516 do {
748af44c 1517 unsigned char *in0 = stream.next_in;
55bb5c91 1518 ret = git_deflate(&stream, Z_FINISH);
748af44c 1519 git_SHA1_Update(&c, in0, stream.next_in - in0);
9892beba
NP
1520 if (write_buffer(fd, compressed, stream.next_out - compressed) < 0)
1521 die("unable to write sha1 file");
1522 stream.next_out = compressed;
1523 stream.avail_out = sizeof(compressed);
1524 } while (ret == Z_OK);
1525
ac54c277
LT
1526 if (ret != Z_STREAM_END)
1527 die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret);
55bb5c91 1528 ret = git_deflate_end_gently(&stream);
ac54c277
LT
1529 if (ret != Z_OK)
1530 die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret);
748af44c
NP
1531 git_SHA1_Final(parano_sha1, &c);
1532 if (hashcmp(sha1, parano_sha1) != 0)
1533 die("confused by unstable object source data for %s", sha1_to_hex(sha1));
ac54c277 1534
e9039dd3 1535 close_sha1_file(fd);
0fcfd160 1536
bbac7311
NP
1537 if (mtime) {
1538 struct utimbuf utb;
1539 utb.actime = mtime;
1540 utb.modtime = mtime;
d4b3d11a 1541 if (utime(tmp_file.buf, &utb) < 0)
7616c6ca 1542 warning_errno("failed utime() on %s", tmp_file.buf);
bbac7311
NP
1543 }
1544
d4b3d11a 1545 return finalize_object_file(tmp_file.buf, filename);
0fcfd160 1546}
8237b185 1547
33d4221c
JK
1548static int freshen_loose_object(const unsigned char *sha1)
1549{
1550 return check_and_freshen(sha1, 1);
1551}
1552
1553static int freshen_packed_object(const unsigned char *sha1)
1554{
1555 struct pack_entry e;
ee1c6c34
JK
1556 if (!find_pack_entry(sha1, &e))
1557 return 0;
1558 if (e.p->freshened)
1559 return 1;
1560 if (!freshen_file(e.p->pack_name))
1561 return 0;
1562 e.p->freshened = 1;
1563 return 1;
33d4221c
JK
1564}
1565
1427a7ff 1566int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *sha1)
bbac7311 1567{
bbac7311 1568 char hdr[32];
ef1286d3 1569 int hdrlen = sizeof(hdr);
bbac7311
NP
1570
1571 /* Normally if we have it in the pack then we do not bother writing
1572 * it out into .git/objects/??/?{38} file.
1573 */
1574 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
b5f52f37 1575 if (freshen_packed_object(sha1) || freshen_loose_object(sha1))
bbac7311
NP
1576 return 0;
1577 return write_loose_object(sha1, hdr, hdrlen, buf, len, 0);
1578}
1579
0c3db67c 1580int hash_sha1_file_literally(const void *buf, unsigned long len, const char *type,
da77611d 1581 struct object_id *oid, unsigned flags)
0c3db67c
ES
1582{
1583 char *header;
1584 int hdrlen, status = 0;
1585
1586 /* type string, SP, %lu of the length plus NUL must fit this */
ef1286d3
JK
1587 hdrlen = strlen(type) + 32;
1588 header = xmalloc(hdrlen);
da77611d 1589 write_sha1_file_prepare(buf, len, type, oid->hash, header, &hdrlen);
0c3db67c
ES
1590
1591 if (!(flags & HASH_WRITE_OBJECT))
1592 goto cleanup;
da77611d 1593 if (freshen_packed_object(oid->hash) || freshen_loose_object(oid->hash))
0c3db67c 1594 goto cleanup;
da77611d 1595 status = write_loose_object(oid->hash, header, hdrlen, buf, len, 0);
0c3db67c
ES
1596
1597cleanup:
1598 free(header);
1599 return status;
1600}
1601
bbac7311
NP
1602int force_object_loose(const unsigned char *sha1, time_t mtime)
1603{
bbac7311
NP
1604 void *buf;
1605 unsigned long len;
1606 enum object_type type;
1607 char hdr[32];
1608 int hdrlen;
1fb23e65 1609 int ret;
bbac7311 1610
c529d75a 1611 if (has_loose_object(sha1))
bbac7311 1612 return 0;
789bf26b 1613 buf = read_object(sha1, &type, &len);
bbac7311
NP
1614 if (!buf)
1615 return error("cannot read sha1_file for %s", sha1_to_hex(sha1));
ef1286d3 1616 hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", typename(type), len) + 1;
1fb23e65
BS
1617 ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime);
1618 free(buf);
1619
1620 return ret;
bbac7311
NP
1621}
1622
0eeb077b 1623int has_sha1_file_with_flags(const unsigned char *sha1, int flags)
8237b185 1624{
3e8b7d3c
JN
1625 if (!startup_info->have_repository)
1626 return 0;
e83e71c5
JT
1627 return sha1_object_info_extended(sha1, NULL,
1628 flags | OBJECT_INFO_SKIP_CACHED) >= 0;
b419aa25 1629}
1630
1631int has_object_file(const struct object_id *oid)
1632{
1633 return has_sha1_file(oid->hash);
8237b185 1634}
74400e71 1635
5827a035
JK
1636int has_object_file_with_flags(const struct object_id *oid, int flags)
1637{
1638 return has_sha1_file_with_flags(oid->hash, flags);
1639}
1640
c879daa2
NTND
1641static void check_tree(const void *buf, size_t size)
1642{
1643 struct tree_desc desc;
1644 struct name_entry entry;
1645
1646 init_tree_desc(&desc, buf, size);
1647 while (tree_entry(&desc, &entry))
1648 /* do nothing
1649 * tree_entry() will die() on malformed entries */
1650 ;
1651}
1652
1653static void check_commit(const void *buf, size_t size)
1654{
1655 struct commit c;
1656 memset(&c, 0, sizeof(c));
1657 if (parse_commit_buffer(&c, buf, size))
1658 die("corrupt commit");
1659}
1660
1661static void check_tag(const void *buf, size_t size)
1662{
1663 struct tag t;
1664 memset(&t, 0, sizeof(t));
1665 if (parse_tag_buffer(&t, buf, size))
1666 die("corrupt tag");
1667}
1668
43df4f86 1669static int index_mem(unsigned char *sha1, void *buf, size_t size,
c4ce46fc
JH
1670 enum object_type type,
1671 const char *path, unsigned flags)
e7332f96 1672{
6c510bee 1673 int ret, re_allocated = 0;
c4ce46fc 1674 int write_object = flags & HASH_WRITE_OBJECT;
74400e71 1675
7672db20 1676 if (!type)
edaec3fb 1677 type = OBJ_BLOB;
6c510bee
LT
1678
1679 /*
1680 * Convert blobs to git internal format
1681 */
43df4f86 1682 if ((type == OBJ_BLOB) && path) {
f285a2d7 1683 struct strbuf nbuf = STRBUF_INIT;
82b474e0 1684 if (convert_to_git(&the_index, path, buf, size, &nbuf,
5e12e78e 1685 write_object ? safe_crlf : SAFE_CRLF_FALSE)) {
b315c5c0 1686 buf = strbuf_detach(&nbuf, &size);
6c510bee
LT
1687 re_allocated = 1;
1688 }
1689 }
c4ce46fc 1690 if (flags & HASH_FORMAT_CHECK) {
c879daa2
NTND
1691 if (type == OBJ_TREE)
1692 check_tree(buf, size);
1693 if (type == OBJ_COMMIT)
1694 check_commit(buf, size);
1695 if (type == OBJ_TAG)
1696 check_tag(buf, size);
1697 }
6c510bee 1698
7672db20 1699 if (write_object)
edaec3fb 1700 ret = write_sha1_file(buf, size, typename(type), sha1);
abdc3fc8 1701 else
edaec3fb 1702 ret = hash_sha1_file(buf, size, typename(type), sha1);
43df4f86 1703 if (re_allocated)
6c510bee 1704 free(buf);
43df4f86
DP
1705 return ret;
1706}
1707
9035d75a
SP
1708static int index_stream_convert_blob(unsigned char *sha1, int fd,
1709 const char *path, unsigned flags)
1710{
1711 int ret;
1712 const int write_object = flags & HASH_WRITE_OBJECT;
1713 struct strbuf sbuf = STRBUF_INIT;
1714
1715 assert(path);
1716 assert(would_convert_to_git_filter_fd(path));
1717
d6c41c20 1718 convert_to_git_filter_fd(&the_index, path, fd, &sbuf,
9035d75a
SP
1719 write_object ? safe_crlf : SAFE_CRLF_FALSE);
1720
1721 if (write_object)
1722 ret = write_sha1_file(sbuf.buf, sbuf.len, typename(OBJ_BLOB),
1723 sha1);
1724 else
1725 ret = hash_sha1_file(sbuf.buf, sbuf.len, typename(OBJ_BLOB),
1726 sha1);
1727 strbuf_release(&sbuf);
1728 return ret;
1729}
1730
7b41e1e1
JH
1731static int index_pipe(unsigned char *sha1, int fd, enum object_type type,
1732 const char *path, unsigned flags)
1733{
1734 struct strbuf sbuf = STRBUF_INIT;
1735 int ret;
1736
1737 if (strbuf_read(&sbuf, fd, 4096) >= 0)
1738 ret = index_mem(sha1, sbuf.buf, sbuf.len, type, path, flags);
1739 else
1740 ret = -1;
1741 strbuf_release(&sbuf);
1742 return ret;
1743}
1744
ea68b0ce
DP
1745#define SMALL_FILE_SIZE (32*1024)
1746
7b41e1e1
JH
1747static int index_core(unsigned char *sha1, int fd, size_t size,
1748 enum object_type type, const char *path,
1749 unsigned flags)
43df4f86
DP
1750{
1751 int ret;
43df4f86 1752
7b41e1e1 1753 if (!size) {
f6a1e1e2 1754 ret = index_mem(sha1, "", size, type, path, flags);
ea68b0ce
DP
1755 } else if (size <= SMALL_FILE_SIZE) {
1756 char *buf = xmalloc(size);
90dca671
JK
1757 ssize_t read_result = read_in_full(fd, buf, size);
1758 if (read_result < 0)
1759 ret = error_errno("read error while indexing %s",
1760 path ? path : "<unknown>");
1761 else if (read_result != size)
1762 ret = error("short read while indexing %s",
1763 path ? path : "<unknown>");
ea68b0ce 1764 else
90dca671 1765 ret = index_mem(sha1, buf, size, type, path, flags);
ea68b0ce 1766 free(buf);
08bda208 1767 } else {
43df4f86 1768 void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
c4ce46fc 1769 ret = index_mem(sha1, buf, size, type, path, flags);
aac17941 1770 munmap(buf, size);
08bda208 1771 }
7b41e1e1
JH
1772 return ret;
1773}
1774
4dd1fbc7 1775/*
568508e7
JH
1776 * This creates one packfile per large blob unless bulk-checkin
1777 * machinery is "plugged".
4dd1fbc7
JH
1778 *
1779 * This also bypasses the usual "convert-to-git" dance, and that is on
1780 * purpose. We could write a streaming version of the converting
1781 * functions and insert that before feeding the data to fast-import
4f22b101
JK
1782 * (or equivalent in-core API described above). However, that is
1783 * somewhat complicated, as we do not know the size of the filter
1784 * result, which we need to know beforehand when writing a git object.
1785 * Since the primary motivation for trying to stream from the working
1786 * tree file and to avoid mmaping it in core is to deal with large
1787 * binary blobs, they generally do not want to get any conversion, and
1788 * callers should avoid this code path when filters are requested.
4dd1fbc7 1789 */
7d5e1dc3 1790static int index_stream(struct object_id *oid, int fd, size_t size,
4dd1fbc7
JH
1791 enum object_type type, const char *path,
1792 unsigned flags)
1793{
7d5e1dc3 1794 return index_bulk_checkin(oid->hash, fd, size, type, path, flags);
4dd1fbc7
JH
1795}
1796
e3506559 1797int index_fd(struct object_id *oid, int fd, struct stat *st,
7b41e1e1
JH
1798 enum object_type type, const char *path, unsigned flags)
1799{
1800 int ret;
7b41e1e1 1801
9079ab7c
SP
1802 /*
1803 * Call xsize_t() only when needed to avoid potentially unnecessary
1804 * die() for large files.
1805 */
9035d75a 1806 if (type == OBJ_BLOB && path && would_convert_to_git_filter_fd(path))
e3506559 1807 ret = index_stream_convert_blob(oid->hash, fd, path, flags);
9035d75a 1808 else if (!S_ISREG(st->st_mode))
e3506559 1809 ret = index_pipe(oid->hash, fd, type, path, flags);
9079ab7c 1810 else if (st->st_size <= big_file_threshold || type != OBJ_BLOB ||
82b474e0 1811 (path && would_convert_to_git(&the_index, path)))
e3506559 1812 ret = index_core(oid->hash, fd, xsize_t(st->st_size), type, path,
9079ab7c 1813 flags);
4dd1fbc7 1814 else
7d5e1dc3 1815 ret = index_stream(oid, fd, xsize_t(st->st_size), type, path,
9079ab7c 1816 flags);
43df4f86 1817 close(fd);
aac17941 1818 return ret;
74400e71 1819}
ec1fcc16 1820
98e019b0 1821int index_path(struct object_id *oid, const char *path, struct stat *st, unsigned flags)
ec1fcc16
JH
1822{
1823 int fd;
b760d3aa 1824 struct strbuf sb = STRBUF_INIT;
ea8e0297 1825 int rc = 0;
ec1fcc16
JH
1826
1827 switch (st->st_mode & S_IFMT) {
1828 case S_IFREG:
1829 fd = open(path, O_RDONLY);
1830 if (fd < 0)
7616c6ca 1831 return error_errno("open(\"%s\")", path);
e3506559 1832 if (index_fd(oid, fd, st, OBJ_BLOB, path, flags) < 0)
ec1fcc16
JH
1833 return error("%s: failed to insert into database",
1834 path);
1835 break;
1836 case S_IFLNK:
7616c6ca
NTND
1837 if (strbuf_readlink(&sb, path, st->st_size))
1838 return error_errno("readlink(\"%s\")", path);
c4ce46fc 1839 if (!(flags & HASH_WRITE_OBJECT))
98e019b0
PO
1840 hash_sha1_file(sb.buf, sb.len, blob_type, oid->hash);
1841 else if (write_sha1_file(sb.buf, sb.len, blob_type, oid->hash))
ea8e0297 1842 rc = error("%s: failed to insert into database", path);
b760d3aa 1843 strbuf_release(&sb);
ec1fcc16 1844 break;
f35a6d3b 1845 case S_IFDIR:
98e019b0 1846 return resolve_gitlink_ref(path, "HEAD", oid->hash);
ec1fcc16
JH
1847 default:
1848 return error("%s: unsupported file type", path);
1849 }
ea8e0297 1850 return rc;
ec1fcc16 1851}
a69e5429
JH
1852
1853int read_pack_header(int fd, struct pack_header *header)
1854{
f48ecd38 1855 if (read_in_full(fd, header, sizeof(*header)) != sizeof(*header))
c697ad14
HO
1856 /* "eof before pack header was fully read" */
1857 return PH_ERROR_EOF;
1858
a69e5429
JH
1859 if (header->hdr_signature != htonl(PACK_SIGNATURE))
1860 /* "protocol error (pack signature mismatch detected)" */
1861 return PH_ERROR_PACK_SIGNATURE;
1862 if (!pack_version_ok(header->hdr_version))
1863 /* "protocol error (pack version unsupported)" */
1864 return PH_ERROR_PROTOCOL;
1865 return 0;
1866}
40d52ff7
JK
1867
1868void assert_sha1_type(const unsigned char *sha1, enum object_type expect)
1869{
1870 enum object_type type = sha1_object_info(sha1, NULL);
1871 if (type < 0)
1872 die("%s is not a valid object", sha1_to_hex(sha1));
1873 if (type != expect)
1874 die("%s is not a valid '%s' object", sha1_to_hex(sha1),
1875 typename(expect));
1876}
27e1e22d 1877
70c49050 1878int for_each_file_in_obj_subdir(unsigned int subdir_nr,
cc817ca3
RS
1879 struct strbuf *path,
1880 each_loose_object_fn obj_cb,
1881 each_loose_cruft_fn cruft_cb,
1882 each_loose_subdir_fn subdir_cb,
1883 void *data)
27e1e22d 1884{
0375f472
RS
1885 size_t origlen, baselen;
1886 DIR *dir;
27e1e22d
JK
1887 struct dirent *de;
1888 int r = 0;
1889
70c49050
RS
1890 if (subdir_nr > 0xff)
1891 BUG("invalid loose object subdirectory: %x", subdir_nr);
1892
0375f472
RS
1893 origlen = path->len;
1894 strbuf_complete(path, '/');
1895 strbuf_addf(path, "%02x", subdir_nr);
1896 baselen = path->len;
1897
1898 dir = opendir(path->buf);
27e1e22d 1899 if (!dir) {
0375f472
RS
1900 if (errno != ENOENT)
1901 r = error_errno("unable to open %s", path->buf);
1902 strbuf_setlen(path, origlen);
1903 return r;
27e1e22d
JK
1904 }
1905
1906 while ((de = readdir(dir))) {
1907 if (is_dot_or_dotdot(de->d_name))
1908 continue;
1909
1910 strbuf_setlen(path, baselen);
1911 strbuf_addf(path, "/%s", de->d_name);
1912
76c1d9a0 1913 if (strlen(de->d_name) == GIT_SHA1_HEXSZ - 2) {
dc01505f 1914 char hex[GIT_MAX_HEXSZ+1];
76c1d9a0 1915 struct object_id oid;
27e1e22d 1916
1a168e5c
JK
1917 xsnprintf(hex, sizeof(hex), "%02x%s",
1918 subdir_nr, de->d_name);
76c1d9a0 1919 if (!get_oid_hex(hex, &oid)) {
27e1e22d 1920 if (obj_cb) {
76c1d9a0 1921 r = obj_cb(&oid, path->buf, data);
27e1e22d
JK
1922 if (r)
1923 break;
1924 }
1925 continue;
1926 }
1927 }
1928
1929 if (cruft_cb) {
1930 r = cruft_cb(de->d_name, path->buf, data);
1931 if (r)
1932 break;
1933 }
1934 }
094c7e63 1935 closedir(dir);
27e1e22d 1936
094c7e63 1937 strbuf_setlen(path, baselen);
27e1e22d
JK
1938 if (!r && subdir_cb)
1939 r = subdir_cb(subdir_nr, path->buf, data);
1940
0375f472
RS
1941 strbuf_setlen(path, origlen);
1942
27e1e22d
JK
1943 return r;
1944}
1945
e6f875e0 1946int for_each_loose_file_in_objdir_buf(struct strbuf *path,
27e1e22d
JK
1947 each_loose_object_fn obj_cb,
1948 each_loose_cruft_fn cruft_cb,
1949 each_loose_subdir_fn subdir_cb,
1950 void *data)
1951{
27e1e22d
JK
1952 int r = 0;
1953 int i;
1954
27e1e22d 1955 for (i = 0; i < 256; i++) {
e6f875e0 1956 r = for_each_file_in_obj_subdir(i, path, obj_cb, cruft_cb,
27e1e22d 1957 subdir_cb, data);
27e1e22d
JK
1958 if (r)
1959 break;
1960 }
1961
e6f875e0
JK
1962 return r;
1963}
1964
1965int for_each_loose_file_in_objdir(const char *path,
1966 each_loose_object_fn obj_cb,
1967 each_loose_cruft_fn cruft_cb,
1968 each_loose_subdir_fn subdir_cb,
1969 void *data)
1970{
1971 struct strbuf buf = STRBUF_INIT;
1972 int r;
1973
1974 strbuf_addstr(&buf, path);
1975 r = for_each_loose_file_in_objdir_buf(&buf, obj_cb, cruft_cb,
1976 subdir_cb, data);
27e1e22d 1977 strbuf_release(&buf);
e6f875e0 1978
27e1e22d
JK
1979 return r;
1980}
660c889e
JK
1981
1982struct loose_alt_odb_data {
1983 each_loose_object_fn *cb;
1984 void *data;
1985};
1986
1987static int loose_from_alt_odb(struct alternate_object_database *alt,
1988 void *vdata)
1989{
1990 struct loose_alt_odb_data *data = vdata;
b0a42642
JM
1991 struct strbuf buf = STRBUF_INIT;
1992 int r;
1993
597f9134 1994 strbuf_addstr(&buf, alt->path);
b0a42642
JM
1995 r = for_each_loose_file_in_objdir_buf(&buf,
1996 data->cb, NULL, NULL,
1997 data->data);
1998 strbuf_release(&buf);
1999 return r;
660c889e
JK
2000}
2001
1385bb7b 2002int for_each_loose_object(each_loose_object_fn cb, void *data, unsigned flags)
660c889e
JK
2003{
2004 struct loose_alt_odb_data alt;
2005 int r;
2006
2007 r = for_each_loose_file_in_objdir(get_object_directory(),
2008 cb, NULL, NULL, data);
2009 if (r)
2010 return r;
2011
1385bb7b
JK
2012 if (flags & FOR_EACH_OBJECT_LOCAL_ONLY)
2013 return 0;
2014
660c889e
JK
2015 alt.cb = cb;
2016 alt.data = data;
2017 return foreach_alt_odb(loose_from_alt_odb, &alt);
2018}
2019
f6371f92
JK
2020static int check_stream_sha1(git_zstream *stream,
2021 const char *hdr,
2022 unsigned long size,
2023 const char *path,
2024 const unsigned char *expected_sha1)
2025{
2026 git_SHA_CTX c;
cd02599c 2027 unsigned char real_sha1[GIT_MAX_RAWSZ];
f6371f92
JK
2028 unsigned char buf[4096];
2029 unsigned long total_read;
2030 int status = Z_OK;
2031
2032 git_SHA1_Init(&c);
2033 git_SHA1_Update(&c, hdr, stream->total_out);
2034
2035 /*
2036 * We already read some bytes into hdr, but the ones up to the NUL
2037 * do not count against the object's content size.
2038 */
2039 total_read = stream->total_out - strlen(hdr) - 1;
2040
2041 /*
2042 * This size comparison must be "<=" to read the final zlib packets;
2043 * see the comment in unpack_sha1_rest for details.
2044 */
2045 while (total_read <= size &&
2046 (status == Z_OK || status == Z_BUF_ERROR)) {
2047 stream->next_out = buf;
2048 stream->avail_out = sizeof(buf);
2049 if (size - total_read < stream->avail_out)
2050 stream->avail_out = size - total_read;
2051 status = git_inflate(stream, Z_FINISH);
2052 git_SHA1_Update(&c, buf, stream->next_out - buf);
2053 total_read += stream->next_out - buf;
2054 }
2055 git_inflate_end(stream);
2056
2057 if (status != Z_STREAM_END) {
2058 error("corrupt loose object '%s'", sha1_to_hex(expected_sha1));
2059 return -1;
2060 }
cce044df
JK
2061 if (stream->avail_in) {
2062 error("garbage at end of loose object '%s'",
2063 sha1_to_hex(expected_sha1));
2064 return -1;
2065 }
f6371f92
JK
2066
2067 git_SHA1_Final(real_sha1, &c);
2068 if (hashcmp(expected_sha1, real_sha1)) {
2069 error("sha1 mismatch for %s (expected %s)", path,
2070 sha1_to_hex(expected_sha1));
2071 return -1;
2072 }
2073
2074 return 0;
2075}
2076
2077int read_loose_object(const char *path,
2078 const unsigned char *expected_sha1,
2079 enum object_type *type,
2080 unsigned long *size,
2081 void **contents)
2082{
2083 int ret = -1;
f6371f92
JK
2084 void *map = NULL;
2085 unsigned long mapsize;
2086 git_zstream stream;
2087 char hdr[32];
2088
2089 *contents = NULL;
2090
2091 map = map_sha1_file_1(path, NULL, &mapsize);
2092 if (!map) {
2093 error_errno("unable to mmap %s", path);
2094 goto out;
2095 }
2096
2097 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0) {
2098 error("unable to unpack header of %s", path);
2099 goto out;
2100 }
2101
2102 *type = parse_sha1_header(hdr, size);
2103 if (*type < 0) {
2104 error("unable to parse header of %s", path);
2105 git_inflate_end(&stream);
2106 goto out;
2107 }
2108
2109 if (*type == OBJ_BLOB) {
2110 if (check_stream_sha1(&stream, hdr, *size, path, expected_sha1) < 0)
2111 goto out;
2112 } else {
2113 *contents = unpack_sha1_rest(&stream, hdr, *size, expected_sha1);
2114 if (!*contents) {
2115 error("unable to unpack contents of %s", path);
2116 git_inflate_end(&stream);
2117 goto out;
2118 }
2119 if (check_sha1_signature(expected_sha1, *contents,
2120 *size, typename(*type))) {
2121 error("sha1 mismatch for %s (expected %s)", path,
2122 sha1_to_hex(expected_sha1));
2123 free(*contents);
2124 goto out;
2125 }
2126 }
2127
2128 ret = 0; /* everything checks out */
2129
2130out:
2131 if (map)
2132 munmap(map, mapsize);
f6371f92
JK
2133 return ret;
2134}