Merge branch 'dl/subtree-limit-to-one-rev'
[git/git.git] / setup.c
1 #include "cache.h"
2 #include "repository.h"
3 #include "config.h"
4 #include "dir.h"
5 #include "string-list.h"
6 #include "chdir-notify.h"
7
8 static int inside_git_dir = -1;
9 static int inside_work_tree = -1;
10 static int work_tree_config_is_bogus;
11
12 static struct startup_info the_startup_info;
13 struct startup_info *startup_info = &the_startup_info;
14
15 /*
16 * The input parameter must contain an absolute path, and it must already be
17 * normalized.
18 *
19 * Find the part of an absolute path that lies inside the work tree by
20 * dereferencing symlinks outside the work tree, for example:
21 * /dir1/repo/dir2/file (work tree is /dir1/repo) -> dir2/file
22 * /dir/file (work tree is /) -> dir/file
23 * /dir/symlink1/symlink2 (symlink1 points to work tree) -> symlink2
24 * /dir/repolink/file (repolink points to /dir/repo) -> file
25 * /dir/repo (exactly equal to work tree) -> (empty string)
26 */
27 static int abspath_part_inside_repo(char *path)
28 {
29 size_t len;
30 size_t wtlen;
31 char *path0;
32 int off;
33 const char *work_tree = get_git_work_tree();
34
35 if (!work_tree)
36 return -1;
37 wtlen = strlen(work_tree);
38 len = strlen(path);
39 off = offset_1st_component(path);
40
41 /* check if work tree is already the prefix */
42 if (wtlen <= len && !fspathncmp(path, work_tree, wtlen)) {
43 if (path[wtlen] == '/') {
44 memmove(path, path + wtlen + 1, len - wtlen);
45 return 0;
46 } else if (path[wtlen - 1] == '/' || path[wtlen] == '\0') {
47 /* work tree is the root, or the whole path */
48 memmove(path, path + wtlen, len - wtlen + 1);
49 return 0;
50 }
51 /* work tree might match beginning of a symlink to work tree */
52 off = wtlen;
53 }
54 path0 = path;
55 path += off;
56
57 /* check each '/'-terminated level */
58 while (*path) {
59 path++;
60 if (*path == '/') {
61 *path = '\0';
62 if (fspathcmp(real_path(path0), work_tree) == 0) {
63 memmove(path0, path + 1, len - (path - path0));
64 return 0;
65 }
66 *path = '/';
67 }
68 }
69
70 /* check whole path */
71 if (fspathcmp(real_path(path0), work_tree) == 0) {
72 *path0 = '\0';
73 return 0;
74 }
75
76 return -1;
77 }
78
79 /*
80 * Normalize "path", prepending the "prefix" for relative paths. If
81 * remaining_prefix is not NULL, return the actual prefix still
82 * remains in the path. For example, prefix = sub1/sub2/ and path is
83 *
84 * foo -> sub1/sub2/foo (full prefix)
85 * ../foo -> sub1/foo (remaining prefix is sub1/)
86 * ../../bar -> bar (no remaining prefix)
87 * ../../sub1/sub2/foo -> sub1/sub2/foo (but no remaining prefix)
88 * `pwd`/../bar -> sub1/bar (no remaining prefix)
89 */
90 char *prefix_path_gently(const char *prefix, int len,
91 int *remaining_prefix, const char *path)
92 {
93 const char *orig = path;
94 char *sanitized;
95 if (is_absolute_path(orig)) {
96 sanitized = xmallocz(strlen(path));
97 if (remaining_prefix)
98 *remaining_prefix = 0;
99 if (normalize_path_copy_len(sanitized, path, remaining_prefix)) {
100 free(sanitized);
101 return NULL;
102 }
103 if (abspath_part_inside_repo(sanitized)) {
104 free(sanitized);
105 return NULL;
106 }
107 } else {
108 sanitized = xstrfmt("%.*s%s", len, len ? prefix : "", path);
109 if (remaining_prefix)
110 *remaining_prefix = len;
111 if (normalize_path_copy_len(sanitized, sanitized, remaining_prefix)) {
112 free(sanitized);
113 return NULL;
114 }
115 }
116 return sanitized;
117 }
118
119 char *prefix_path(const char *prefix, int len, const char *path)
120 {
121 char *r = prefix_path_gently(prefix, len, NULL, path);
122 if (!r)
123 die(_("'%s' is outside repository"), path);
124 return r;
125 }
126
127 int path_inside_repo(const char *prefix, const char *path)
128 {
129 int len = prefix ? strlen(prefix) : 0;
130 char *r = prefix_path_gently(prefix, len, NULL, path);
131 if (r) {
132 free(r);
133 return 1;
134 }
135 return 0;
136 }
137
138 int check_filename(const char *prefix, const char *arg)
139 {
140 char *to_free = NULL;
141 struct stat st;
142
143 if (skip_prefix(arg, ":/", &arg)) {
144 if (!*arg) /* ":/" is root dir, always exists */
145 return 1;
146 prefix = NULL;
147 } else if (skip_prefix(arg, ":!", &arg) ||
148 skip_prefix(arg, ":^", &arg)) {
149 if (!*arg) /* excluding everything is silly, but allowed */
150 return 1;
151 }
152
153 if (prefix)
154 arg = to_free = prefix_filename(prefix, arg);
155
156 if (!lstat(arg, &st)) {
157 free(to_free);
158 return 1; /* file exists */
159 }
160 if (is_missing_file_error(errno)) {
161 free(to_free);
162 return 0; /* file does not exist */
163 }
164 die_errno(_("failed to stat '%s'"), arg);
165 }
166
167 static void NORETURN die_verify_filename(const char *prefix,
168 const char *arg,
169 int diagnose_misspelt_rev)
170 {
171 if (!diagnose_misspelt_rev)
172 die(_("%s: no such path in the working tree.\n"
173 "Use 'git <command> -- <path>...' to specify paths that do not exist locally."),
174 arg);
175 /*
176 * Saying "'(icase)foo' does not exist in the index" when the
177 * user gave us ":(icase)foo" is just stupid. A magic pathspec
178 * begins with a colon and is followed by a non-alnum; do not
179 * let maybe_die_on_misspelt_object_name() even trigger.
180 */
181 if (!(arg[0] == ':' && !isalnum(arg[1])))
182 maybe_die_on_misspelt_object_name(arg, prefix);
183
184 /* ... or fall back the most general message. */
185 die(_("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
186 "Use '--' to separate paths from revisions, like this:\n"
187 "'git <command> [<revision>...] -- [<file>...]'"), arg);
188
189 }
190
191 /*
192 * Check for arguments that don't resolve as actual files,
193 * but which look sufficiently like pathspecs that we'll consider
194 * them such for the purposes of rev/pathspec DWIM parsing.
195 */
196 static int looks_like_pathspec(const char *arg)
197 {
198 /* anything with a wildcard character */
199 if (!no_wildcard(arg))
200 return 1;
201
202 /* long-form pathspec magic */
203 if (starts_with(arg, ":("))
204 return 1;
205
206 return 0;
207 }
208
209 /*
210 * Verify a filename that we got as an argument for a pathspec
211 * entry. Note that a filename that begins with "-" never verifies
212 * as true, because even if such a filename were to exist, we want
213 * it to be preceded by the "--" marker (or we want the user to
214 * use a format like "./-filename")
215 *
216 * The "diagnose_misspelt_rev" is used to provide a user-friendly
217 * diagnosis when dying upon finding that "name" is not a pathname.
218 * If set to 1, the diagnosis will try to diagnose "name" as an
219 * invalid object name (e.g. HEAD:foo). If set to 0, the diagnosis
220 * will only complain about an inexisting file.
221 *
222 * This function is typically called to check that a "file or rev"
223 * argument is unambiguous. In this case, the caller will want
224 * diagnose_misspelt_rev == 1 when verifying the first non-rev
225 * argument (which could have been a revision), and
226 * diagnose_misspelt_rev == 0 for the next ones (because we already
227 * saw a filename, there's not ambiguity anymore).
228 */
229 void verify_filename(const char *prefix,
230 const char *arg,
231 int diagnose_misspelt_rev)
232 {
233 if (*arg == '-')
234 die(_("option '%s' must come before non-option arguments"), arg);
235 if (looks_like_pathspec(arg) || check_filename(prefix, arg))
236 return;
237 die_verify_filename(prefix, arg, diagnose_misspelt_rev);
238 }
239
240 /*
241 * Opposite of the above: the command line did not have -- marker
242 * and we parsed the arg as a refname. It should not be interpretable
243 * as a filename.
244 */
245 void verify_non_filename(const char *prefix, const char *arg)
246 {
247 if (!is_inside_work_tree() || is_inside_git_dir())
248 return;
249 if (*arg == '-')
250 return; /* flag */
251 if (!check_filename(prefix, arg))
252 return;
253 die(_("ambiguous argument '%s': both revision and filename\n"
254 "Use '--' to separate paths from revisions, like this:\n"
255 "'git <command> [<revision>...] -- [<file>...]'"), arg);
256 }
257
258 int get_common_dir(struct strbuf *sb, const char *gitdir)
259 {
260 const char *git_env_common_dir = getenv(GIT_COMMON_DIR_ENVIRONMENT);
261 if (git_env_common_dir) {
262 strbuf_addstr(sb, git_env_common_dir);
263 return 1;
264 } else {
265 return get_common_dir_noenv(sb, gitdir);
266 }
267 }
268
269 int get_common_dir_noenv(struct strbuf *sb, const char *gitdir)
270 {
271 struct strbuf data = STRBUF_INIT;
272 struct strbuf path = STRBUF_INIT;
273 int ret = 0;
274
275 strbuf_addf(&path, "%s/commondir", gitdir);
276 if (file_exists(path.buf)) {
277 if (strbuf_read_file(&data, path.buf, 0) <= 0)
278 die_errno(_("failed to read %s"), path.buf);
279 while (data.len && (data.buf[data.len - 1] == '\n' ||
280 data.buf[data.len - 1] == '\r'))
281 data.len--;
282 data.buf[data.len] = '\0';
283 strbuf_reset(&path);
284 if (!is_absolute_path(data.buf))
285 strbuf_addf(&path, "%s/", gitdir);
286 strbuf_addbuf(&path, &data);
287 strbuf_add_real_path(sb, path.buf);
288 ret = 1;
289 } else {
290 strbuf_addstr(sb, gitdir);
291 }
292
293 strbuf_release(&data);
294 strbuf_release(&path);
295 return ret;
296 }
297
298 /*
299 * Test if it looks like we're at a git directory.
300 * We want to see:
301 *
302 * - either an objects/ directory _or_ the proper
303 * GIT_OBJECT_DIRECTORY environment variable
304 * - a refs/ directory
305 * - either a HEAD symlink or a HEAD file that is formatted as
306 * a proper "ref:", or a regular file HEAD that has a properly
307 * formatted sha1 object name.
308 */
309 int is_git_directory(const char *suspect)
310 {
311 struct strbuf path = STRBUF_INIT;
312 int ret = 0;
313 size_t len;
314
315 /* Check worktree-related signatures */
316 strbuf_addstr(&path, suspect);
317 strbuf_complete(&path, '/');
318 strbuf_addstr(&path, "HEAD");
319 if (validate_headref(path.buf))
320 goto done;
321
322 strbuf_reset(&path);
323 get_common_dir(&path, suspect);
324 len = path.len;
325
326 /* Check non-worktree-related signatures */
327 if (getenv(DB_ENVIRONMENT)) {
328 if (access(getenv(DB_ENVIRONMENT), X_OK))
329 goto done;
330 }
331 else {
332 strbuf_setlen(&path, len);
333 strbuf_addstr(&path, "/objects");
334 if (access(path.buf, X_OK))
335 goto done;
336 }
337
338 strbuf_setlen(&path, len);
339 strbuf_addstr(&path, "/refs");
340 if (access(path.buf, X_OK))
341 goto done;
342
343 ret = 1;
344 done:
345 strbuf_release(&path);
346 return ret;
347 }
348
349 int is_nonbare_repository_dir(struct strbuf *path)
350 {
351 int ret = 0;
352 int gitfile_error;
353 size_t orig_path_len = path->len;
354 assert(orig_path_len != 0);
355 strbuf_complete(path, '/');
356 strbuf_addstr(path, ".git");
357 if (read_gitfile_gently(path->buf, &gitfile_error) || is_git_directory(path->buf))
358 ret = 1;
359 if (gitfile_error == READ_GITFILE_ERR_OPEN_FAILED ||
360 gitfile_error == READ_GITFILE_ERR_READ_FAILED)
361 ret = 1;
362 strbuf_setlen(path, orig_path_len);
363 return ret;
364 }
365
366 int is_inside_git_dir(void)
367 {
368 if (inside_git_dir < 0)
369 inside_git_dir = is_inside_dir(get_git_dir());
370 return inside_git_dir;
371 }
372
373 int is_inside_work_tree(void)
374 {
375 if (inside_work_tree < 0)
376 inside_work_tree = is_inside_dir(get_git_work_tree());
377 return inside_work_tree;
378 }
379
380 void setup_work_tree(void)
381 {
382 const char *work_tree;
383 static int initialized = 0;
384
385 if (initialized)
386 return;
387
388 if (work_tree_config_is_bogus)
389 die(_("unable to set up work tree using invalid config"));
390
391 work_tree = get_git_work_tree();
392 if (!work_tree || chdir_notify(work_tree))
393 die(_("this operation must be run in a work tree"));
394
395 /*
396 * Make sure subsequent git processes find correct worktree
397 * if $GIT_WORK_TREE is set relative
398 */
399 if (getenv(GIT_WORK_TREE_ENVIRONMENT))
400 setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
401
402 initialized = 1;
403 }
404
405 static int read_worktree_config(const char *var, const char *value, void *vdata)
406 {
407 struct repository_format *data = vdata;
408
409 if (strcmp(var, "core.bare") == 0) {
410 data->is_bare = git_config_bool(var, value);
411 } else if (strcmp(var, "core.worktree") == 0) {
412 if (!value)
413 return config_error_nonbool(var);
414 free(data->work_tree);
415 data->work_tree = xstrdup(value);
416 }
417 return 0;
418 }
419
420 static int check_repo_format(const char *var, const char *value, void *vdata)
421 {
422 struct repository_format *data = vdata;
423 const char *ext;
424
425 if (strcmp(var, "core.repositoryformatversion") == 0)
426 data->version = git_config_int(var, value);
427 else if (skip_prefix(var, "extensions.", &ext)) {
428 /*
429 * record any known extensions here; otherwise,
430 * we fall through to recording it as unknown, and
431 * check_repository_format will complain
432 */
433 if (!strcmp(ext, "noop"))
434 ;
435 else if (!strcmp(ext, "preciousobjects"))
436 data->precious_objects = git_config_bool(var, value);
437 else if (!strcmp(ext, "partialclone")) {
438 if (!value)
439 return config_error_nonbool(var);
440 data->partial_clone = xstrdup(value);
441 } else if (!strcmp(ext, "worktreeconfig"))
442 data->worktree_config = git_config_bool(var, value);
443 else
444 string_list_append(&data->unknown_extensions, ext);
445 }
446
447 return read_worktree_config(var, value, vdata);
448 }
449
450 static int check_repository_format_gently(const char *gitdir, struct repository_format *candidate, int *nongit_ok)
451 {
452 struct strbuf sb = STRBUF_INIT;
453 struct strbuf err = STRBUF_INIT;
454 int has_common;
455
456 has_common = get_common_dir(&sb, gitdir);
457 strbuf_addstr(&sb, "/config");
458 read_repository_format(candidate, sb.buf);
459 strbuf_release(&sb);
460
461 /*
462 * For historical use of check_repository_format() in git-init,
463 * we treat a missing config as a silent "ok", even when nongit_ok
464 * is unset.
465 */
466 if (candidate->version < 0)
467 return 0;
468
469 if (verify_repository_format(candidate, &err) < 0) {
470 if (nongit_ok) {
471 warning("%s", err.buf);
472 strbuf_release(&err);
473 *nongit_ok = -1;
474 return -1;
475 }
476 die("%s", err.buf);
477 }
478
479 repository_format_precious_objects = candidate->precious_objects;
480 repository_format_partial_clone = xstrdup_or_null(candidate->partial_clone);
481 repository_format_worktree_config = candidate->worktree_config;
482 string_list_clear(&candidate->unknown_extensions, 0);
483
484 if (repository_format_worktree_config) {
485 /*
486 * pick up core.bare and core.worktree from per-worktree
487 * config if present
488 */
489 strbuf_addf(&sb, "%s/config.worktree", gitdir);
490 git_config_from_file(read_worktree_config, sb.buf, candidate);
491 strbuf_release(&sb);
492 has_common = 0;
493 }
494
495 if (!has_common) {
496 if (candidate->is_bare != -1) {
497 is_bare_repository_cfg = candidate->is_bare;
498 if (is_bare_repository_cfg == 1)
499 inside_work_tree = -1;
500 }
501 if (candidate->work_tree) {
502 free(git_work_tree_cfg);
503 git_work_tree_cfg = xstrdup(candidate->work_tree);
504 inside_work_tree = -1;
505 }
506 }
507
508 return 0;
509 }
510
511 static void init_repository_format(struct repository_format *format)
512 {
513 const struct repository_format fresh = REPOSITORY_FORMAT_INIT;
514
515 memcpy(format, &fresh, sizeof(fresh));
516 }
517
518 int read_repository_format(struct repository_format *format, const char *path)
519 {
520 clear_repository_format(format);
521 git_config_from_file(check_repo_format, path, format);
522 if (format->version == -1)
523 clear_repository_format(format);
524 return format->version;
525 }
526
527 void clear_repository_format(struct repository_format *format)
528 {
529 string_list_clear(&format->unknown_extensions, 0);
530 free(format->work_tree);
531 free(format->partial_clone);
532 init_repository_format(format);
533 }
534
535 int verify_repository_format(const struct repository_format *format,
536 struct strbuf *err)
537 {
538 if (GIT_REPO_VERSION_READ < format->version) {
539 strbuf_addf(err, _("Expected git repo version <= %d, found %d"),
540 GIT_REPO_VERSION_READ, format->version);
541 return -1;
542 }
543
544 if (format->version >= 1 && format->unknown_extensions.nr) {
545 int i;
546
547 strbuf_addstr(err, _("unknown repository extensions found:"));
548
549 for (i = 0; i < format->unknown_extensions.nr; i++)
550 strbuf_addf(err, "\n\t%s",
551 format->unknown_extensions.items[i].string);
552 return -1;
553 }
554
555 return 0;
556 }
557
558 void read_gitfile_error_die(int error_code, const char *path, const char *dir)
559 {
560 switch (error_code) {
561 case READ_GITFILE_ERR_STAT_FAILED:
562 case READ_GITFILE_ERR_NOT_A_FILE:
563 /* non-fatal; follow return path */
564 break;
565 case READ_GITFILE_ERR_OPEN_FAILED:
566 die_errno(_("error opening '%s'"), path);
567 case READ_GITFILE_ERR_TOO_LARGE:
568 die(_("too large to be a .git file: '%s'"), path);
569 case READ_GITFILE_ERR_READ_FAILED:
570 die(_("error reading %s"), path);
571 case READ_GITFILE_ERR_INVALID_FORMAT:
572 die(_("invalid gitfile format: %s"), path);
573 case READ_GITFILE_ERR_NO_PATH:
574 die(_("no path in gitfile: %s"), path);
575 case READ_GITFILE_ERR_NOT_A_REPO:
576 die(_("not a git repository: %s"), dir);
577 default:
578 BUG("unknown error code");
579 }
580 }
581
582 /*
583 * Try to read the location of the git directory from the .git file,
584 * return path to git directory if found. The return value comes from
585 * a shared buffer.
586 *
587 * On failure, if return_error_code is not NULL, return_error_code
588 * will be set to an error code and NULL will be returned. If
589 * return_error_code is NULL the function will die instead (for most
590 * cases).
591 */
592 const char *read_gitfile_gently(const char *path, int *return_error_code)
593 {
594 const int max_file_size = 1 << 20; /* 1MB */
595 int error_code = 0;
596 char *buf = NULL;
597 char *dir = NULL;
598 const char *slash;
599 struct stat st;
600 int fd;
601 ssize_t len;
602
603 if (stat(path, &st)) {
604 /* NEEDSWORK: discern between ENOENT vs other errors */
605 error_code = READ_GITFILE_ERR_STAT_FAILED;
606 goto cleanup_return;
607 }
608 if (!S_ISREG(st.st_mode)) {
609 error_code = READ_GITFILE_ERR_NOT_A_FILE;
610 goto cleanup_return;
611 }
612 if (st.st_size > max_file_size) {
613 error_code = READ_GITFILE_ERR_TOO_LARGE;
614 goto cleanup_return;
615 }
616 fd = open(path, O_RDONLY);
617 if (fd < 0) {
618 error_code = READ_GITFILE_ERR_OPEN_FAILED;
619 goto cleanup_return;
620 }
621 buf = xmallocz(st.st_size);
622 len = read_in_full(fd, buf, st.st_size);
623 close(fd);
624 if (len != st.st_size) {
625 error_code = READ_GITFILE_ERR_READ_FAILED;
626 goto cleanup_return;
627 }
628 if (!starts_with(buf, "gitdir: ")) {
629 error_code = READ_GITFILE_ERR_INVALID_FORMAT;
630 goto cleanup_return;
631 }
632 while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
633 len--;
634 if (len < 9) {
635 error_code = READ_GITFILE_ERR_NO_PATH;
636 goto cleanup_return;
637 }
638 buf[len] = '\0';
639 dir = buf + 8;
640
641 if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
642 size_t pathlen = slash+1 - path;
643 dir = xstrfmt("%.*s%.*s", (int)pathlen, path,
644 (int)(len - 8), buf + 8);
645 free(buf);
646 buf = dir;
647 }
648 if (!is_git_directory(dir)) {
649 error_code = READ_GITFILE_ERR_NOT_A_REPO;
650 goto cleanup_return;
651 }
652 path = real_path(dir);
653
654 cleanup_return:
655 if (return_error_code)
656 *return_error_code = error_code;
657 else if (error_code)
658 read_gitfile_error_die(error_code, path, dir);
659
660 free(buf);
661 return error_code ? NULL : path;
662 }
663
664 static const char *setup_explicit_git_dir(const char *gitdirenv,
665 struct strbuf *cwd,
666 struct repository_format *repo_fmt,
667 int *nongit_ok)
668 {
669 const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
670 const char *worktree;
671 char *gitfile;
672 int offset;
673
674 if (PATH_MAX - 40 < strlen(gitdirenv))
675 die(_("'$%s' too big"), GIT_DIR_ENVIRONMENT);
676
677 gitfile = (char*)read_gitfile(gitdirenv);
678 if (gitfile) {
679 gitfile = xstrdup(gitfile);
680 gitdirenv = gitfile;
681 }
682
683 if (!is_git_directory(gitdirenv)) {
684 if (nongit_ok) {
685 *nongit_ok = 1;
686 free(gitfile);
687 return NULL;
688 }
689 die(_("not a git repository: '%s'"), gitdirenv);
690 }
691
692 if (check_repository_format_gently(gitdirenv, repo_fmt, nongit_ok)) {
693 free(gitfile);
694 return NULL;
695 }
696
697 /* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
698 if (work_tree_env)
699 set_git_work_tree(work_tree_env);
700 else if (is_bare_repository_cfg > 0) {
701 if (git_work_tree_cfg) {
702 /* #22.2, #30 */
703 warning("core.bare and core.worktree do not make sense");
704 work_tree_config_is_bogus = 1;
705 }
706
707 /* #18, #26 */
708 set_git_dir(gitdirenv);
709 free(gitfile);
710 return NULL;
711 }
712 else if (git_work_tree_cfg) { /* #6, #14 */
713 if (is_absolute_path(git_work_tree_cfg))
714 set_git_work_tree(git_work_tree_cfg);
715 else {
716 char *core_worktree;
717 if (chdir(gitdirenv))
718 die_errno(_("cannot chdir to '%s'"), gitdirenv);
719 if (chdir(git_work_tree_cfg))
720 die_errno(_("cannot chdir to '%s'"), git_work_tree_cfg);
721 core_worktree = xgetcwd();
722 if (chdir(cwd->buf))
723 die_errno(_("cannot come back to cwd"));
724 set_git_work_tree(core_worktree);
725 free(core_worktree);
726 }
727 }
728 else if (!git_env_bool(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, 1)) {
729 /* #16d */
730 set_git_dir(gitdirenv);
731 free(gitfile);
732 return NULL;
733 }
734 else /* #2, #10 */
735 set_git_work_tree(".");
736
737 /* set_git_work_tree() must have been called by now */
738 worktree = get_git_work_tree();
739
740 /* both get_git_work_tree() and cwd are already normalized */
741 if (!strcmp(cwd->buf, worktree)) { /* cwd == worktree */
742 set_git_dir(gitdirenv);
743 free(gitfile);
744 return NULL;
745 }
746
747 offset = dir_inside_of(cwd->buf, worktree);
748 if (offset >= 0) { /* cwd inside worktree? */
749 set_git_dir(real_path(gitdirenv));
750 if (chdir(worktree))
751 die_errno(_("cannot chdir to '%s'"), worktree);
752 strbuf_addch(cwd, '/');
753 free(gitfile);
754 return cwd->buf + offset;
755 }
756
757 /* cwd outside worktree */
758 set_git_dir(gitdirenv);
759 free(gitfile);
760 return NULL;
761 }
762
763 static const char *setup_discovered_git_dir(const char *gitdir,
764 struct strbuf *cwd, int offset,
765 struct repository_format *repo_fmt,
766 int *nongit_ok)
767 {
768 if (check_repository_format_gently(gitdir, repo_fmt, nongit_ok))
769 return NULL;
770
771 /* --work-tree is set without --git-dir; use discovered one */
772 if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
773 char *to_free = NULL;
774 const char *ret;
775
776 if (offset != cwd->len && !is_absolute_path(gitdir))
777 gitdir = to_free = real_pathdup(gitdir, 1);
778 if (chdir(cwd->buf))
779 die_errno(_("cannot come back to cwd"));
780 ret = setup_explicit_git_dir(gitdir, cwd, repo_fmt, nongit_ok);
781 free(to_free);
782 return ret;
783 }
784
785 /* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
786 if (is_bare_repository_cfg > 0) {
787 set_git_dir(offset == cwd->len ? gitdir : real_path(gitdir));
788 if (chdir(cwd->buf))
789 die_errno(_("cannot come back to cwd"));
790 return NULL;
791 }
792
793 /* #0, #1, #5, #8, #9, #12, #13 */
794 set_git_work_tree(".");
795 if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
796 set_git_dir(gitdir);
797 inside_git_dir = 0;
798 inside_work_tree = 1;
799 if (offset == cwd->len)
800 return NULL;
801
802 /* Make "offset" point past the '/' (already the case for root dirs) */
803 if (offset != offset_1st_component(cwd->buf))
804 offset++;
805 /* Add a '/' at the end */
806 strbuf_addch(cwd, '/');
807 return cwd->buf + offset;
808 }
809
810 /* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
811 static const char *setup_bare_git_dir(struct strbuf *cwd, int offset,
812 struct repository_format *repo_fmt,
813 int *nongit_ok)
814 {
815 int root_len;
816
817 if (check_repository_format_gently(".", repo_fmt, nongit_ok))
818 return NULL;
819
820 setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
821
822 /* --work-tree is set without --git-dir; use discovered one */
823 if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
824 static const char *gitdir;
825
826 gitdir = offset == cwd->len ? "." : xmemdupz(cwd->buf, offset);
827 if (chdir(cwd->buf))
828 die_errno(_("cannot come back to cwd"));
829 return setup_explicit_git_dir(gitdir, cwd, repo_fmt, nongit_ok);
830 }
831
832 inside_git_dir = 1;
833 inside_work_tree = 0;
834 if (offset != cwd->len) {
835 if (chdir(cwd->buf))
836 die_errno(_("cannot come back to cwd"));
837 root_len = offset_1st_component(cwd->buf);
838 strbuf_setlen(cwd, offset > root_len ? offset : root_len);
839 set_git_dir(cwd->buf);
840 }
841 else
842 set_git_dir(".");
843 return NULL;
844 }
845
846 static dev_t get_device_or_die(const char *path, const char *prefix, int prefix_len)
847 {
848 struct stat buf;
849 if (stat(path, &buf)) {
850 die_errno(_("failed to stat '%*s%s%s'"),
851 prefix_len,
852 prefix ? prefix : "",
853 prefix ? "/" : "", path);
854 }
855 return buf.st_dev;
856 }
857
858 /*
859 * A "string_list_each_func_t" function that canonicalizes an entry
860 * from GIT_CEILING_DIRECTORIES using real_path_if_valid(), or
861 * discards it if unusable. The presence of an empty entry in
862 * GIT_CEILING_DIRECTORIES turns off canonicalization for all
863 * subsequent entries.
864 */
865 static int canonicalize_ceiling_entry(struct string_list_item *item,
866 void *cb_data)
867 {
868 int *empty_entry_found = cb_data;
869 char *ceil = item->string;
870
871 if (!*ceil) {
872 *empty_entry_found = 1;
873 return 0;
874 } else if (!is_absolute_path(ceil)) {
875 return 0;
876 } else if (*empty_entry_found) {
877 /* Keep entry but do not canonicalize it */
878 return 1;
879 } else {
880 char *real_path = real_pathdup(ceil, 0);
881 if (!real_path) {
882 return 0;
883 }
884 free(item->string);
885 item->string = real_path;
886 return 1;
887 }
888 }
889
890 enum discovery_result {
891 GIT_DIR_NONE = 0,
892 GIT_DIR_EXPLICIT,
893 GIT_DIR_DISCOVERED,
894 GIT_DIR_BARE,
895 /* these are errors */
896 GIT_DIR_HIT_CEILING = -1,
897 GIT_DIR_HIT_MOUNT_POINT = -2,
898 GIT_DIR_INVALID_GITFILE = -3
899 };
900
901 /*
902 * We cannot decide in this function whether we are in the work tree or
903 * not, since the config can only be read _after_ this function was called.
904 *
905 * Also, we avoid changing any global state (such as the current working
906 * directory) to allow early callers.
907 *
908 * The directory where the search should start needs to be passed in via the
909 * `dir` parameter; upon return, the `dir` buffer will contain the path of
910 * the directory where the search ended, and `gitdir` will contain the path of
911 * the discovered .git/ directory, if any. If `gitdir` is not absolute, it
912 * is relative to `dir` (i.e. *not* necessarily the cwd).
913 */
914 static enum discovery_result setup_git_directory_gently_1(struct strbuf *dir,
915 struct strbuf *gitdir,
916 int die_on_error)
917 {
918 const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
919 struct string_list ceiling_dirs = STRING_LIST_INIT_DUP;
920 const char *gitdirenv;
921 int ceil_offset = -1, min_offset = has_dos_drive_prefix(dir->buf) ? 3 : 1;
922 dev_t current_device = 0;
923 int one_filesystem = 1;
924
925 /*
926 * If GIT_DIR is set explicitly, we're not going
927 * to do any discovery, but we still do repository
928 * validation.
929 */
930 gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
931 if (gitdirenv) {
932 strbuf_addstr(gitdir, gitdirenv);
933 return GIT_DIR_EXPLICIT;
934 }
935
936 if (env_ceiling_dirs) {
937 int empty_entry_found = 0;
938
939 string_list_split(&ceiling_dirs, env_ceiling_dirs, PATH_SEP, -1);
940 filter_string_list(&ceiling_dirs, 0,
941 canonicalize_ceiling_entry, &empty_entry_found);
942 ceil_offset = longest_ancestor_length(dir->buf, &ceiling_dirs);
943 string_list_clear(&ceiling_dirs, 0);
944 }
945
946 if (ceil_offset < 0)
947 ceil_offset = min_offset - 2;
948
949 /*
950 * Test in the following order (relative to the dir):
951 * - .git (file containing "gitdir: <path>")
952 * - .git/
953 * - ./ (bare)
954 * - ../.git
955 * - ../.git/
956 * - ../ (bare)
957 * - ../../.git
958 * etc.
959 */
960 one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
961 if (one_filesystem)
962 current_device = get_device_or_die(dir->buf, NULL, 0);
963 for (;;) {
964 int offset = dir->len, error_code = 0;
965
966 if (offset > min_offset)
967 strbuf_addch(dir, '/');
968 strbuf_addstr(dir, DEFAULT_GIT_DIR_ENVIRONMENT);
969 gitdirenv = read_gitfile_gently(dir->buf, die_on_error ?
970 NULL : &error_code);
971 if (!gitdirenv) {
972 if (die_on_error ||
973 error_code == READ_GITFILE_ERR_NOT_A_FILE) {
974 /* NEEDSWORK: fail if .git is not file nor dir */
975 if (is_git_directory(dir->buf))
976 gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
977 } else if (error_code != READ_GITFILE_ERR_STAT_FAILED)
978 return GIT_DIR_INVALID_GITFILE;
979 }
980 strbuf_setlen(dir, offset);
981 if (gitdirenv) {
982 strbuf_addstr(gitdir, gitdirenv);
983 return GIT_DIR_DISCOVERED;
984 }
985
986 if (is_git_directory(dir->buf)) {
987 strbuf_addstr(gitdir, ".");
988 return GIT_DIR_BARE;
989 }
990
991 if (offset <= min_offset)
992 return GIT_DIR_HIT_CEILING;
993
994 while (--offset > ceil_offset && !is_dir_sep(dir->buf[offset]))
995 ; /* continue */
996 if (offset <= ceil_offset)
997 return GIT_DIR_HIT_CEILING;
998
999 strbuf_setlen(dir, offset > min_offset ? offset : min_offset);
1000 if (one_filesystem &&
1001 current_device != get_device_or_die(dir->buf, NULL, offset))
1002 return GIT_DIR_HIT_MOUNT_POINT;
1003 }
1004 }
1005
1006 int discover_git_directory(struct strbuf *commondir,
1007 struct strbuf *gitdir)
1008 {
1009 struct strbuf dir = STRBUF_INIT, err = STRBUF_INIT;
1010 size_t gitdir_offset = gitdir->len, cwd_len;
1011 size_t commondir_offset = commondir->len;
1012 struct repository_format candidate = REPOSITORY_FORMAT_INIT;
1013
1014 if (strbuf_getcwd(&dir))
1015 return -1;
1016
1017 cwd_len = dir.len;
1018 if (setup_git_directory_gently_1(&dir, gitdir, 0) <= 0) {
1019 strbuf_release(&dir);
1020 return -1;
1021 }
1022
1023 /*
1024 * The returned gitdir is relative to dir, and if dir does not reflect
1025 * the current working directory, we simply make the gitdir absolute.
1026 */
1027 if (dir.len < cwd_len && !is_absolute_path(gitdir->buf + gitdir_offset)) {
1028 /* Avoid a trailing "/." */
1029 if (!strcmp(".", gitdir->buf + gitdir_offset))
1030 strbuf_setlen(gitdir, gitdir_offset);
1031 else
1032 strbuf_addch(&dir, '/');
1033 strbuf_insert(gitdir, gitdir_offset, dir.buf, dir.len);
1034 }
1035
1036 get_common_dir(commondir, gitdir->buf + gitdir_offset);
1037
1038 strbuf_reset(&dir);
1039 strbuf_addf(&dir, "%s/config", commondir->buf + commondir_offset);
1040 read_repository_format(&candidate, dir.buf);
1041 strbuf_release(&dir);
1042
1043 if (verify_repository_format(&candidate, &err) < 0) {
1044 warning("ignoring git dir '%s': %s",
1045 gitdir->buf + gitdir_offset, err.buf);
1046 strbuf_release(&err);
1047 strbuf_setlen(commondir, commondir_offset);
1048 strbuf_setlen(gitdir, gitdir_offset);
1049 clear_repository_format(&candidate);
1050 return -1;
1051 }
1052
1053 clear_repository_format(&candidate);
1054 return 0;
1055 }
1056
1057 const char *setup_git_directory_gently(int *nongit_ok)
1058 {
1059 static struct strbuf cwd = STRBUF_INIT;
1060 struct strbuf dir = STRBUF_INIT, gitdir = STRBUF_INIT;
1061 const char *prefix = NULL;
1062 struct repository_format repo_fmt = REPOSITORY_FORMAT_INIT;
1063
1064 /*
1065 * We may have read an incomplete configuration before
1066 * setting-up the git directory. If so, clear the cache so
1067 * that the next queries to the configuration reload complete
1068 * configuration (including the per-repo config file that we
1069 * ignored previously).
1070 */
1071 git_config_clear();
1072
1073 /*
1074 * Let's assume that we are in a git repository.
1075 * If it turns out later that we are somewhere else, the value will be
1076 * updated accordingly.
1077 */
1078 if (nongit_ok)
1079 *nongit_ok = 0;
1080
1081 if (strbuf_getcwd(&cwd))
1082 die_errno(_("Unable to read current working directory"));
1083 strbuf_addbuf(&dir, &cwd);
1084
1085 switch (setup_git_directory_gently_1(&dir, &gitdir, 1)) {
1086 case GIT_DIR_EXPLICIT:
1087 prefix = setup_explicit_git_dir(gitdir.buf, &cwd, &repo_fmt, nongit_ok);
1088 break;
1089 case GIT_DIR_DISCOVERED:
1090 if (dir.len < cwd.len && chdir(dir.buf))
1091 die(_("cannot change to '%s'"), dir.buf);
1092 prefix = setup_discovered_git_dir(gitdir.buf, &cwd, dir.len,
1093 &repo_fmt, nongit_ok);
1094 break;
1095 case GIT_DIR_BARE:
1096 if (dir.len < cwd.len && chdir(dir.buf))
1097 die(_("cannot change to '%s'"), dir.buf);
1098 prefix = setup_bare_git_dir(&cwd, dir.len, &repo_fmt, nongit_ok);
1099 break;
1100 case GIT_DIR_HIT_CEILING:
1101 if (!nongit_ok)
1102 die(_("not a git repository (or any of the parent directories): %s"),
1103 DEFAULT_GIT_DIR_ENVIRONMENT);
1104 *nongit_ok = 1;
1105 break;
1106 case GIT_DIR_HIT_MOUNT_POINT:
1107 if (!nongit_ok)
1108 die(_("not a git repository (or any parent up to mount point %s)\n"
1109 "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set)."),
1110 dir.buf);
1111 *nongit_ok = 1;
1112 break;
1113 case GIT_DIR_NONE:
1114 /*
1115 * As a safeguard against setup_git_directory_gently_1 returning
1116 * this value, fallthrough to BUG. Otherwise it is possible to
1117 * set startup_info->have_repository to 1 when we did nothing to
1118 * find a repository.
1119 */
1120 default:
1121 BUG("unhandled setup_git_directory_1() result");
1122 }
1123
1124 /*
1125 * At this point, nongit_ok is stable. If it is non-NULL and points
1126 * to a non-zero value, then this means that we haven't found a
1127 * repository and that the caller expects startup_info to reflect
1128 * this.
1129 *
1130 * Regardless of the state of nongit_ok, startup_info->prefix and
1131 * the GIT_PREFIX environment variable must always match. For details
1132 * see Documentation/config/alias.txt.
1133 */
1134 if (nongit_ok && *nongit_ok) {
1135 startup_info->have_repository = 0;
1136 startup_info->prefix = NULL;
1137 setenv(GIT_PREFIX_ENVIRONMENT, "", 1);
1138 } else {
1139 startup_info->have_repository = 1;
1140 startup_info->prefix = prefix;
1141 if (prefix)
1142 setenv(GIT_PREFIX_ENVIRONMENT, prefix, 1);
1143 else
1144 setenv(GIT_PREFIX_ENVIRONMENT, "", 1);
1145 }
1146
1147 /*
1148 * Not all paths through the setup code will call 'set_git_dir()' (which
1149 * directly sets up the environment) so in order to guarantee that the
1150 * environment is in a consistent state after setup, explicitly setup
1151 * the environment if we have a repository.
1152 *
1153 * NEEDSWORK: currently we allow bogus GIT_DIR values to be set in some
1154 * code paths so we also need to explicitly setup the environment if
1155 * the user has set GIT_DIR. It may be beneficial to disallow bogus
1156 * GIT_DIR values at some point in the future.
1157 */
1158 if (/* GIT_DIR_EXPLICIT, GIT_DIR_DISCOVERED, GIT_DIR_BARE */
1159 startup_info->have_repository ||
1160 /* GIT_DIR_EXPLICIT */
1161 getenv(GIT_DIR_ENVIRONMENT)) {
1162 if (!the_repository->gitdir) {
1163 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
1164 if (!gitdir)
1165 gitdir = DEFAULT_GIT_DIR_ENVIRONMENT;
1166 setup_git_env(gitdir);
1167 }
1168 if (startup_info->have_repository)
1169 repo_set_hash_algo(the_repository, repo_fmt.hash_algo);
1170 }
1171
1172 strbuf_release(&dir);
1173 strbuf_release(&gitdir);
1174 clear_repository_format(&repo_fmt);
1175
1176 return prefix;
1177 }
1178
1179 int git_config_perm(const char *var, const char *value)
1180 {
1181 int i;
1182 char *endptr;
1183
1184 if (value == NULL)
1185 return PERM_GROUP;
1186
1187 if (!strcmp(value, "umask"))
1188 return PERM_UMASK;
1189 if (!strcmp(value, "group"))
1190 return PERM_GROUP;
1191 if (!strcmp(value, "all") ||
1192 !strcmp(value, "world") ||
1193 !strcmp(value, "everybody"))
1194 return PERM_EVERYBODY;
1195
1196 /* Parse octal numbers */
1197 i = strtol(value, &endptr, 8);
1198
1199 /* If not an octal number, maybe true/false? */
1200 if (*endptr != 0)
1201 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
1202
1203 /*
1204 * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
1205 * a chmod value to restrict to.
1206 */
1207 switch (i) {
1208 case PERM_UMASK: /* 0 */
1209 return PERM_UMASK;
1210 case OLD_PERM_GROUP: /* 1 */
1211 return PERM_GROUP;
1212 case OLD_PERM_EVERYBODY: /* 2 */
1213 return PERM_EVERYBODY;
1214 }
1215
1216 /* A filemode value was given: 0xxx */
1217
1218 if ((i & 0600) != 0600)
1219 die(_("problem with core.sharedRepository filemode value "
1220 "(0%.3o).\nThe owner of files must always have "
1221 "read and write permissions."), i);
1222
1223 /*
1224 * Mask filemode value. Others can not get write permission.
1225 * x flags for directories are handled separately.
1226 */
1227 return -(i & 0666);
1228 }
1229
1230 void check_repository_format(void)
1231 {
1232 struct repository_format repo_fmt = REPOSITORY_FORMAT_INIT;
1233 check_repository_format_gently(get_git_dir(), &repo_fmt, NULL);
1234 startup_info->have_repository = 1;
1235 clear_repository_format(&repo_fmt);
1236 }
1237
1238 /*
1239 * Returns the "prefix", a path to the current working directory
1240 * relative to the work tree root, or NULL, if the current working
1241 * directory is not a strict subdirectory of the work tree root. The
1242 * prefix always ends with a '/' character.
1243 */
1244 const char *setup_git_directory(void)
1245 {
1246 return setup_git_directory_gently(NULL);
1247 }
1248
1249 const char *resolve_gitdir_gently(const char *suspect, int *return_error_code)
1250 {
1251 if (is_git_directory(suspect))
1252 return suspect;
1253 return read_gitfile_gently(suspect, return_error_code);
1254 }
1255
1256 /* if any standard file descriptor is missing open it to /dev/null */
1257 void sanitize_stdfds(void)
1258 {
1259 int fd = open("/dev/null", O_RDWR, 0);
1260 while (fd != -1 && fd < 2)
1261 fd = dup(fd);
1262 if (fd == -1)
1263 die_errno(_("open /dev/null or dup failed"));
1264 if (fd > 2)
1265 close(fd);
1266 }
1267
1268 int daemonize(void)
1269 {
1270 #ifdef NO_POSIX_GOODIES
1271 errno = ENOSYS;
1272 return -1;
1273 #else
1274 switch (fork()) {
1275 case 0:
1276 break;
1277 case -1:
1278 die_errno(_("fork failed"));
1279 default:
1280 exit(0);
1281 }
1282 if (setsid() == -1)
1283 die_errno(_("setsid failed"));
1284 close(0);
1285 close(1);
1286 close(2);
1287 sanitize_stdfds();
1288 return 0;
1289 #endif
1290 }