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