Merge branch 'cb/test-use-ere-for-alternation'
[git.git] / path.c
blob8b2c7531919eef89b340b3323d1cbd806ba57b0c
1 /*
2 * Utilities for paths and pathnames
3 */
4 #include "cache.h"
5 #include "repository.h"
6 #include "strbuf.h"
7 #include "string-list.h"
8 #include "dir.h"
9 #include "worktree.h"
10 #include "submodule-config.h"
11 #include "path.h"
12 #include "packfile.h"
13 #include "object-store.h"
14 #include "lockfile.h"
16 static int get_st_mode_bits(const char *path, int *mode)
18 struct stat st;
19 if (lstat(path, &st) < 0)
20 return -1;
21 *mode = st.st_mode;
22 return 0;
25 static char bad_path[] = "/bad-path/";
27 static struct strbuf *get_pathname(void)
29 static struct strbuf pathname_array[4] = {
30 STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
32 static int index;
33 struct strbuf *sb = &pathname_array[index];
34 index = (index + 1) % ARRAY_SIZE(pathname_array);
35 strbuf_reset(sb);
36 return sb;
39 static const char *cleanup_path(const char *path)
41 /* Clean it up */
42 if (skip_prefix(path, "./", &path)) {
43 while (*path == '/')
44 path++;
46 return path;
49 static void strbuf_cleanup_path(struct strbuf *sb)
51 const char *path = cleanup_path(sb->buf);
52 if (path > sb->buf)
53 strbuf_remove(sb, 0, path - sb->buf);
56 char *mksnpath(char *buf, size_t n, const char *fmt, ...)
58 va_list args;
59 unsigned len;
61 va_start(args, fmt);
62 len = vsnprintf(buf, n, fmt, args);
63 va_end(args);
64 if (len >= n) {
65 strlcpy(buf, bad_path, n);
66 return buf;
68 return (char *)cleanup_path(buf);
71 static int dir_prefix(const char *buf, const char *dir)
73 int len = strlen(dir);
74 return !strncmp(buf, dir, len) &&
75 (is_dir_sep(buf[len]) || buf[len] == '\0');
78 /* $buf =~ m|$dir/+$file| but without regex */
79 static int is_dir_file(const char *buf, const char *dir, const char *file)
81 int len = strlen(dir);
82 if (strncmp(buf, dir, len) || !is_dir_sep(buf[len]))
83 return 0;
84 while (is_dir_sep(buf[len]))
85 len++;
86 return !strcmp(buf + len, file);
89 static void replace_dir(struct strbuf *buf, int len, const char *newdir)
91 int newlen = strlen(newdir);
92 int need_sep = (buf->buf[len] && !is_dir_sep(buf->buf[len])) &&
93 !is_dir_sep(newdir[newlen - 1]);
94 if (need_sep)
95 len--; /* keep one char, to be replaced with '/' */
96 strbuf_splice(buf, 0, len, newdir, newlen);
97 if (need_sep)
98 buf->buf[newlen] = '/';
101 struct common_dir {
102 /* Not considered garbage for report_linked_checkout_garbage */
103 unsigned ignore_garbage:1;
104 unsigned is_dir:1;
105 /* Belongs to the common dir, though it may contain paths that don't */
106 unsigned is_common:1;
107 const char *path;
110 static struct common_dir common_list[] = {
111 { 0, 1, 1, "branches" },
112 { 0, 1, 1, "common" },
113 { 0, 1, 1, "hooks" },
114 { 0, 1, 1, "info" },
115 { 0, 0, 0, "info/sparse-checkout" },
116 { 1, 1, 1, "logs" },
117 { 1, 0, 0, "logs/HEAD" },
118 { 0, 1, 0, "logs/refs/bisect" },
119 { 0, 1, 0, "logs/refs/rewritten" },
120 { 0, 1, 0, "logs/refs/worktree" },
121 { 0, 1, 1, "lost-found" },
122 { 0, 1, 1, "objects" },
123 { 0, 1, 1, "refs" },
124 { 0, 1, 0, "refs/bisect" },
125 { 0, 1, 0, "refs/rewritten" },
126 { 0, 1, 0, "refs/worktree" },
127 { 0, 1, 1, "remotes" },
128 { 0, 1, 1, "worktrees" },
129 { 0, 1, 1, "rr-cache" },
130 { 0, 1, 1, "svn" },
131 { 0, 0, 1, "config" },
132 { 1, 0, 1, "gc.pid" },
133 { 0, 0, 1, "packed-refs" },
134 { 0, 0, 1, "shallow" },
135 { 0, 0, 0, NULL }
139 * A compressed trie. A trie node consists of zero or more characters that
140 * are common to all elements with this prefix, optionally followed by some
141 * children. If value is not NULL, the trie node is a terminal node.
143 * For example, consider the following set of strings:
144 * abc
145 * def
146 * definite
147 * definition
149 * The trie would look like:
150 * root: len = 0, children a and d non-NULL, value = NULL.
151 * a: len = 2, contents = bc, value = (data for "abc")
152 * d: len = 2, contents = ef, children i non-NULL, value = (data for "def")
153 * i: len = 3, contents = nit, children e and i non-NULL, value = NULL
154 * e: len = 0, children all NULL, value = (data for "definite")
155 * i: len = 2, contents = on, children all NULL,
156 * value = (data for "definition")
158 struct trie {
159 struct trie *children[256];
160 int len;
161 char *contents;
162 void *value;
165 static struct trie *make_trie_node(const char *key, void *value)
167 struct trie *new_node = xcalloc(1, sizeof(*new_node));
168 new_node->len = strlen(key);
169 if (new_node->len) {
170 new_node->contents = xmalloc(new_node->len);
171 memcpy(new_node->contents, key, new_node->len);
173 new_node->value = value;
174 return new_node;
178 * Add a key/value pair to a trie. The key is assumed to be \0-terminated.
179 * If there was an existing value for this key, return it.
181 static void *add_to_trie(struct trie *root, const char *key, void *value)
183 struct trie *child;
184 void *old;
185 int i;
187 if (!*key) {
188 /* we have reached the end of the key */
189 old = root->value;
190 root->value = value;
191 return old;
194 for (i = 0; i < root->len; i++) {
195 if (root->contents[i] == key[i])
196 continue;
199 * Split this node: child will contain this node's
200 * existing children.
202 child = xmalloc(sizeof(*child));
203 memcpy(child->children, root->children, sizeof(root->children));
205 child->len = root->len - i - 1;
206 if (child->len) {
207 child->contents = xstrndup(root->contents + i + 1,
208 child->len);
210 child->value = root->value;
211 root->value = NULL;
212 root->len = i;
214 memset(root->children, 0, sizeof(root->children));
215 root->children[(unsigned char)root->contents[i]] = child;
217 /* This is the newly-added child. */
218 root->children[(unsigned char)key[i]] =
219 make_trie_node(key + i + 1, value);
220 return NULL;
223 /* We have matched the entire compressed section */
224 if (key[i]) {
225 child = root->children[(unsigned char)key[root->len]];
226 if (child) {
227 return add_to_trie(child, key + root->len + 1, value);
228 } else {
229 child = make_trie_node(key + root->len + 1, value);
230 root->children[(unsigned char)key[root->len]] = child;
231 return NULL;
235 old = root->value;
236 root->value = value;
237 return old;
240 typedef int (*match_fn)(const char *unmatched, void *value, void *baton);
243 * Search a trie for some key. Find the longest /-or-\0-terminated
244 * prefix of the key for which the trie contains a value. If there is
245 * no such prefix, return -1. Otherwise call fn with the unmatched
246 * portion of the key and the found value. If fn returns 0 or
247 * positive, then return its return value. If fn returns negative,
248 * then call fn with the next-longest /-terminated prefix of the key
249 * (i.e. a parent directory) for which the trie contains a value, and
250 * handle its return value the same way. If there is no shorter
251 * /-terminated prefix with a value left, then return the negative
252 * return value of the most recent fn invocation.
254 * The key is partially normalized: consecutive slashes are skipped.
256 * For example, consider the trie containing only [logs,
257 * logs/refs/bisect], both with values, but not logs/refs.
259 * | key | unmatched | prefix to node | return value |
260 * |--------------------|----------------|------------------|--------------|
261 * | a | not called | n/a | -1 |
262 * | logstore | not called | n/a | -1 |
263 * | logs | \0 | logs | as per fn |
264 * | logs/ | / | logs | as per fn |
265 * | logs/refs | /refs | logs | as per fn |
266 * | logs/refs/ | /refs/ | logs | as per fn |
267 * | logs/refs/b | /refs/b | logs | as per fn |
268 * | logs/refs/bisected | /refs/bisected | logs | as per fn |
269 * | logs/refs/bisect | \0 | logs/refs/bisect | as per fn |
270 * | logs/refs/bisect/ | / | logs/refs/bisect | as per fn |
271 * | logs/refs/bisect/a | /a | logs/refs/bisect | as per fn |
272 * | (If fn in the previous line returns -1, then fn is called once more:) |
273 * | logs/refs/bisect/a | /refs/bisect/a | logs | as per fn |
274 * |--------------------|----------------|------------------|--------------|
276 static int trie_find(struct trie *root, const char *key, match_fn fn,
277 void *baton)
279 int i;
280 int result;
281 struct trie *child;
283 if (!*key) {
284 /* we have reached the end of the key */
285 if (root->value && !root->len)
286 return fn(key, root->value, baton);
287 else
288 return -1;
291 for (i = 0; i < root->len; i++) {
292 /* Partial path normalization: skip consecutive slashes. */
293 if (key[i] == '/' && key[i+1] == '/') {
294 key++;
295 continue;
297 if (root->contents[i] != key[i])
298 return -1;
301 /* Matched the entire compressed section */
302 key += i;
303 if (!*key) {
304 /* End of key */
305 if (root->value)
306 return fn(key, root->value, baton);
307 else
308 return -1;
311 /* Partial path normalization: skip consecutive slashes */
312 while (key[0] == '/' && key[1] == '/')
313 key++;
315 child = root->children[(unsigned char)*key];
316 if (child)
317 result = trie_find(child, key + 1, fn, baton);
318 else
319 result = -1;
321 if (result >= 0 || (*key != '/' && *key != 0))
322 return result;
323 if (root->value)
324 return fn(key, root->value, baton);
325 else
326 return -1;
329 static struct trie common_trie;
330 static int common_trie_done_setup;
332 static void init_common_trie(void)
334 struct common_dir *p;
336 if (common_trie_done_setup)
337 return;
339 for (p = common_list; p->path; p++)
340 add_to_trie(&common_trie, p->path, p);
342 common_trie_done_setup = 1;
346 * Helper function for update_common_dir: returns 1 if the dir
347 * prefix is common.
349 static int check_common(const char *unmatched, void *value, void *baton)
351 struct common_dir *dir = value;
353 if (dir->is_dir && (unmatched[0] == 0 || unmatched[0] == '/'))
354 return dir->is_common;
356 if (!dir->is_dir && unmatched[0] == 0)
357 return dir->is_common;
359 return 0;
362 static void update_common_dir(struct strbuf *buf, int git_dir_len,
363 const char *common_dir)
365 char *base = buf->buf + git_dir_len;
366 int has_lock_suffix = strbuf_strip_suffix(buf, LOCK_SUFFIX);
368 init_common_trie();
369 if (trie_find(&common_trie, base, check_common, NULL) > 0)
370 replace_dir(buf, git_dir_len, common_dir);
372 if (has_lock_suffix)
373 strbuf_addstr(buf, LOCK_SUFFIX);
376 void report_linked_checkout_garbage(void)
378 struct strbuf sb = STRBUF_INIT;
379 const struct common_dir *p;
380 int len;
382 if (!the_repository->different_commondir)
383 return;
384 strbuf_addf(&sb, "%s/", get_git_dir());
385 len = sb.len;
386 for (p = common_list; p->path; p++) {
387 const char *path = p->path;
388 if (p->ignore_garbage)
389 continue;
390 strbuf_setlen(&sb, len);
391 strbuf_addstr(&sb, path);
392 if (file_exists(sb.buf))
393 report_garbage(PACKDIR_FILE_GARBAGE, sb.buf);
395 strbuf_release(&sb);
398 static void adjust_git_path(const struct repository *repo,
399 struct strbuf *buf, int git_dir_len)
401 const char *base = buf->buf + git_dir_len;
402 if (is_dir_file(base, "info", "grafts"))
403 strbuf_splice(buf, 0, buf->len,
404 repo->graft_file, strlen(repo->graft_file));
405 else if (!strcmp(base, "index"))
406 strbuf_splice(buf, 0, buf->len,
407 repo->index_file, strlen(repo->index_file));
408 else if (dir_prefix(base, "objects"))
409 replace_dir(buf, git_dir_len + 7, repo->objects->odb->path);
410 else if (git_hooks_path && dir_prefix(base, "hooks"))
411 replace_dir(buf, git_dir_len + 5, git_hooks_path);
412 else if (repo->different_commondir)
413 update_common_dir(buf, git_dir_len, repo->commondir);
416 static void strbuf_worktree_gitdir(struct strbuf *buf,
417 const struct repository *repo,
418 const struct worktree *wt)
420 if (!wt)
421 strbuf_addstr(buf, repo->gitdir);
422 else if (!wt->id)
423 strbuf_addstr(buf, repo->commondir);
424 else
425 strbuf_git_common_path(buf, repo, "worktrees/%s", wt->id);
428 static void do_git_path(const struct repository *repo,
429 const struct worktree *wt, struct strbuf *buf,
430 const char *fmt, va_list args)
432 int gitdir_len;
433 strbuf_worktree_gitdir(buf, repo, wt);
434 if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
435 strbuf_addch(buf, '/');
436 gitdir_len = buf->len;
437 strbuf_vaddf(buf, fmt, args);
438 if (!wt)
439 adjust_git_path(repo, buf, gitdir_len);
440 strbuf_cleanup_path(buf);
443 char *repo_git_path(const struct repository *repo,
444 const char *fmt, ...)
446 struct strbuf path = STRBUF_INIT;
447 va_list args;
448 va_start(args, fmt);
449 do_git_path(repo, NULL, &path, fmt, args);
450 va_end(args);
451 return strbuf_detach(&path, NULL);
454 void strbuf_repo_git_path(struct strbuf *sb,
455 const struct repository *repo,
456 const char *fmt, ...)
458 va_list args;
459 va_start(args, fmt);
460 do_git_path(repo, NULL, sb, fmt, args);
461 va_end(args);
464 char *git_path_buf(struct strbuf *buf, const char *fmt, ...)
466 va_list args;
467 strbuf_reset(buf);
468 va_start(args, fmt);
469 do_git_path(the_repository, NULL, buf, fmt, args);
470 va_end(args);
471 return buf->buf;
474 void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
476 va_list args;
477 va_start(args, fmt);
478 do_git_path(the_repository, NULL, sb, fmt, args);
479 va_end(args);
482 const char *git_path(const char *fmt, ...)
484 struct strbuf *pathname = get_pathname();
485 va_list args;
486 va_start(args, fmt);
487 do_git_path(the_repository, NULL, pathname, fmt, args);
488 va_end(args);
489 return pathname->buf;
492 char *git_pathdup(const char *fmt, ...)
494 struct strbuf path = STRBUF_INIT;
495 va_list args;
496 va_start(args, fmt);
497 do_git_path(the_repository, NULL, &path, fmt, args);
498 va_end(args);
499 return strbuf_detach(&path, NULL);
502 char *mkpathdup(const char *fmt, ...)
504 struct strbuf sb = STRBUF_INIT;
505 va_list args;
506 va_start(args, fmt);
507 strbuf_vaddf(&sb, fmt, args);
508 va_end(args);
509 strbuf_cleanup_path(&sb);
510 return strbuf_detach(&sb, NULL);
513 const char *mkpath(const char *fmt, ...)
515 va_list args;
516 struct strbuf *pathname = get_pathname();
517 va_start(args, fmt);
518 strbuf_vaddf(pathname, fmt, args);
519 va_end(args);
520 return cleanup_path(pathname->buf);
523 const char *worktree_git_path(const struct worktree *wt, const char *fmt, ...)
525 struct strbuf *pathname = get_pathname();
526 va_list args;
527 va_start(args, fmt);
528 do_git_path(the_repository, wt, pathname, fmt, args);
529 va_end(args);
530 return pathname->buf;
533 static void do_worktree_path(const struct repository *repo,
534 struct strbuf *buf,
535 const char *fmt, va_list args)
537 strbuf_addstr(buf, repo->worktree);
538 if(buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
539 strbuf_addch(buf, '/');
541 strbuf_vaddf(buf, fmt, args);
542 strbuf_cleanup_path(buf);
545 char *repo_worktree_path(const struct repository *repo, const char *fmt, ...)
547 struct strbuf path = STRBUF_INIT;
548 va_list args;
550 if (!repo->worktree)
551 return NULL;
553 va_start(args, fmt);
554 do_worktree_path(repo, &path, fmt, args);
555 va_end(args);
557 return strbuf_detach(&path, NULL);
560 void strbuf_repo_worktree_path(struct strbuf *sb,
561 const struct repository *repo,
562 const char *fmt, ...)
564 va_list args;
566 if (!repo->worktree)
567 return;
569 va_start(args, fmt);
570 do_worktree_path(repo, sb, fmt, args);
571 va_end(args);
574 /* Returns 0 on success, negative on failure. */
575 static int do_submodule_path(struct strbuf *buf, const char *path,
576 const char *fmt, va_list args)
578 struct strbuf git_submodule_common_dir = STRBUF_INIT;
579 struct strbuf git_submodule_dir = STRBUF_INIT;
580 int ret;
582 ret = submodule_to_gitdir(&git_submodule_dir, path);
583 if (ret)
584 goto cleanup;
586 strbuf_complete(&git_submodule_dir, '/');
587 strbuf_addbuf(buf, &git_submodule_dir);
588 strbuf_vaddf(buf, fmt, args);
590 if (get_common_dir_noenv(&git_submodule_common_dir, git_submodule_dir.buf))
591 update_common_dir(buf, git_submodule_dir.len, git_submodule_common_dir.buf);
593 strbuf_cleanup_path(buf);
595 cleanup:
596 strbuf_release(&git_submodule_dir);
597 strbuf_release(&git_submodule_common_dir);
598 return ret;
601 char *git_pathdup_submodule(const char *path, const char *fmt, ...)
603 int err;
604 va_list args;
605 struct strbuf buf = STRBUF_INIT;
606 va_start(args, fmt);
607 err = do_submodule_path(&buf, path, fmt, args);
608 va_end(args);
609 if (err) {
610 strbuf_release(&buf);
611 return NULL;
613 return strbuf_detach(&buf, NULL);
616 int strbuf_git_path_submodule(struct strbuf *buf, const char *path,
617 const char *fmt, ...)
619 int err;
620 va_list args;
621 va_start(args, fmt);
622 err = do_submodule_path(buf, path, fmt, args);
623 va_end(args);
625 return err;
628 static void do_git_common_path(const struct repository *repo,
629 struct strbuf *buf,
630 const char *fmt,
631 va_list args)
633 strbuf_addstr(buf, repo->commondir);
634 if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
635 strbuf_addch(buf, '/');
636 strbuf_vaddf(buf, fmt, args);
637 strbuf_cleanup_path(buf);
640 const char *git_common_path(const char *fmt, ...)
642 struct strbuf *pathname = get_pathname();
643 va_list args;
644 va_start(args, fmt);
645 do_git_common_path(the_repository, pathname, fmt, args);
646 va_end(args);
647 return pathname->buf;
650 void strbuf_git_common_path(struct strbuf *sb,
651 const struct repository *repo,
652 const char *fmt, ...)
654 va_list args;
655 va_start(args, fmt);
656 do_git_common_path(repo, sb, fmt, args);
657 va_end(args);
660 int validate_headref(const char *path)
662 struct stat st;
663 char buffer[256];
664 const char *refname;
665 struct object_id oid;
666 int fd;
667 ssize_t len;
669 if (lstat(path, &st) < 0)
670 return -1;
672 /* Make sure it is a "refs/.." symlink */
673 if (S_ISLNK(st.st_mode)) {
674 len = readlink(path, buffer, sizeof(buffer)-1);
675 if (len >= 5 && !memcmp("refs/", buffer, 5))
676 return 0;
677 return -1;
681 * Anything else, just open it and try to see if it is a symbolic ref.
683 fd = open(path, O_RDONLY);
684 if (fd < 0)
685 return -1;
686 len = read_in_full(fd, buffer, sizeof(buffer)-1);
687 close(fd);
689 if (len < 0)
690 return -1;
691 buffer[len] = '\0';
694 * Is it a symbolic ref?
696 if (skip_prefix(buffer, "ref:", &refname)) {
697 while (isspace(*refname))
698 refname++;
699 if (starts_with(refname, "refs/"))
700 return 0;
704 * Is this a detached HEAD?
706 if (!get_oid_hex(buffer, &oid))
707 return 0;
709 return -1;
712 static struct passwd *getpw_str(const char *username, size_t len)
714 struct passwd *pw;
715 char *username_z = xmemdupz(username, len);
716 pw = getpwnam(username_z);
717 free(username_z);
718 return pw;
722 * Return a string with ~ and ~user expanded via getpw*. If buf != NULL,
723 * then it is a newly allocated string. Returns NULL on getpw failure or
724 * if path is NULL.
726 * If real_home is true, strbuf_realpath($HOME) is used in the expansion.
728 char *expand_user_path(const char *path, int real_home)
730 struct strbuf user_path = STRBUF_INIT;
731 const char *to_copy = path;
733 if (path == NULL)
734 goto return_null;
735 if (path[0] == '~') {
736 const char *first_slash = strchrnul(path, '/');
737 const char *username = path + 1;
738 size_t username_len = first_slash - username;
739 if (username_len == 0) {
740 const char *home = getenv("HOME");
741 if (!home)
742 goto return_null;
743 if (real_home)
744 strbuf_add_real_path(&user_path, home);
745 else
746 strbuf_addstr(&user_path, home);
747 #ifdef GIT_WINDOWS_NATIVE
748 convert_slashes(user_path.buf);
749 #endif
750 } else {
751 struct passwd *pw = getpw_str(username, username_len);
752 if (!pw)
753 goto return_null;
754 strbuf_addstr(&user_path, pw->pw_dir);
756 to_copy = first_slash;
758 strbuf_addstr(&user_path, to_copy);
759 return strbuf_detach(&user_path, NULL);
760 return_null:
761 strbuf_release(&user_path);
762 return NULL;
766 * First, one directory to try is determined by the following algorithm.
768 * (0) If "strict" is given, the path is used as given and no DWIM is
769 * done. Otherwise:
770 * (1) "~/path" to mean path under the running user's home directory;
771 * (2) "~user/path" to mean path under named user's home directory;
772 * (3) "relative/path" to mean cwd relative directory; or
773 * (4) "/absolute/path" to mean absolute directory.
775 * Unless "strict" is given, we check "%s/.git", "%s", "%s.git/.git", "%s.git"
776 * in this order. We select the first one that is a valid git repository, and
777 * chdir() to it. If none match, or we fail to chdir, we return NULL.
779 * If all goes well, we return the directory we used to chdir() (but
780 * before ~user is expanded), avoiding getcwd() resolving symbolic
781 * links. User relative paths are also returned as they are given,
782 * except DWIM suffixing.
784 const char *enter_repo(const char *path, int strict)
786 static struct strbuf validated_path = STRBUF_INIT;
787 static struct strbuf used_path = STRBUF_INIT;
789 if (!path)
790 return NULL;
792 if (!strict) {
793 static const char *suffix[] = {
794 "/.git", "", ".git/.git", ".git", NULL,
796 const char *gitfile;
797 int len = strlen(path);
798 int i;
799 while ((1 < len) && (path[len-1] == '/'))
800 len--;
803 * We can handle arbitrary-sized buffers, but this remains as a
804 * sanity check on untrusted input.
806 if (PATH_MAX <= len)
807 return NULL;
809 strbuf_reset(&used_path);
810 strbuf_reset(&validated_path);
811 strbuf_add(&used_path, path, len);
812 strbuf_add(&validated_path, path, len);
814 if (used_path.buf[0] == '~') {
815 char *newpath = expand_user_path(used_path.buf, 0);
816 if (!newpath)
817 return NULL;
818 strbuf_attach(&used_path, newpath, strlen(newpath),
819 strlen(newpath));
821 for (i = 0; suffix[i]; i++) {
822 struct stat st;
823 size_t baselen = used_path.len;
824 strbuf_addstr(&used_path, suffix[i]);
825 if (!stat(used_path.buf, &st) &&
826 (S_ISREG(st.st_mode) ||
827 (S_ISDIR(st.st_mode) && is_git_directory(used_path.buf)))) {
828 strbuf_addstr(&validated_path, suffix[i]);
829 break;
831 strbuf_setlen(&used_path, baselen);
833 if (!suffix[i])
834 return NULL;
835 gitfile = read_gitfile(used_path.buf);
836 if (gitfile) {
837 strbuf_reset(&used_path);
838 strbuf_addstr(&used_path, gitfile);
840 if (chdir(used_path.buf))
841 return NULL;
842 path = validated_path.buf;
844 else {
845 const char *gitfile = read_gitfile(path);
846 if (gitfile)
847 path = gitfile;
848 if (chdir(path))
849 return NULL;
852 if (is_git_directory(".")) {
853 set_git_dir(".", 0);
854 check_repository_format(NULL);
855 return path;
858 return NULL;
861 static int calc_shared_perm(int mode)
863 int tweak;
865 if (get_shared_repository() < 0)
866 tweak = -get_shared_repository();
867 else
868 tweak = get_shared_repository();
870 if (!(mode & S_IWUSR))
871 tweak &= ~0222;
872 if (mode & S_IXUSR)
873 /* Copy read bits to execute bits */
874 tweak |= (tweak & 0444) >> 2;
875 if (get_shared_repository() < 0)
876 mode = (mode & ~0777) | tweak;
877 else
878 mode |= tweak;
880 return mode;
884 int adjust_shared_perm(const char *path)
886 int old_mode, new_mode;
888 if (!get_shared_repository())
889 return 0;
890 if (get_st_mode_bits(path, &old_mode) < 0)
891 return -1;
893 new_mode = calc_shared_perm(old_mode);
894 if (S_ISDIR(old_mode)) {
895 /* Copy read bits to execute bits */
896 new_mode |= (new_mode & 0444) >> 2;
897 new_mode |= FORCE_DIR_SET_GID;
900 if (((old_mode ^ new_mode) & ~S_IFMT) &&
901 chmod(path, (new_mode & ~S_IFMT)) < 0)
902 return -2;
903 return 0;
906 void safe_create_dir(const char *dir, int share)
908 if (mkdir(dir, 0777) < 0) {
909 if (errno != EEXIST) {
910 perror(dir);
911 exit(1);
914 else if (share && adjust_shared_perm(dir))
915 die(_("Could not make %s writable by group"), dir);
918 static int have_same_root(const char *path1, const char *path2)
920 int is_abs1, is_abs2;
922 is_abs1 = is_absolute_path(path1);
923 is_abs2 = is_absolute_path(path2);
924 return (is_abs1 && is_abs2 && tolower(path1[0]) == tolower(path2[0])) ||
925 (!is_abs1 && !is_abs2);
929 * Give path as relative to prefix.
931 * The strbuf may or may not be used, so do not assume it contains the
932 * returned path.
934 const char *relative_path(const char *in, const char *prefix,
935 struct strbuf *sb)
937 int in_len = in ? strlen(in) : 0;
938 int prefix_len = prefix ? strlen(prefix) : 0;
939 int in_off = 0;
940 int prefix_off = 0;
941 int i = 0, j = 0;
943 if (!in_len)
944 return "./";
945 else if (!prefix_len)
946 return in;
948 if (have_same_root(in, prefix))
949 /* bypass dos_drive, for "c:" is identical to "C:" */
950 i = j = has_dos_drive_prefix(in);
951 else {
952 return in;
955 while (i < prefix_len && j < in_len && prefix[i] == in[j]) {
956 if (is_dir_sep(prefix[i])) {
957 while (is_dir_sep(prefix[i]))
958 i++;
959 while (is_dir_sep(in[j]))
960 j++;
961 prefix_off = i;
962 in_off = j;
963 } else {
964 i++;
965 j++;
969 if (
970 /* "prefix" seems like prefix of "in" */
971 i >= prefix_len &&
973 * but "/foo" is not a prefix of "/foobar"
974 * (i.e. prefix not end with '/')
976 prefix_off < prefix_len) {
977 if (j >= in_len) {
978 /* in="/a/b", prefix="/a/b" */
979 in_off = in_len;
980 } else if (is_dir_sep(in[j])) {
981 /* in="/a/b/c", prefix="/a/b" */
982 while (is_dir_sep(in[j]))
983 j++;
984 in_off = j;
985 } else {
986 /* in="/a/bbb/c", prefix="/a/b" */
987 i = prefix_off;
989 } else if (
990 /* "in" is short than "prefix" */
991 j >= in_len &&
992 /* "in" not end with '/' */
993 in_off < in_len) {
994 if (is_dir_sep(prefix[i])) {
995 /* in="/a/b", prefix="/a/b/c/" */
996 while (is_dir_sep(prefix[i]))
997 i++;
998 in_off = in_len;
1001 in += in_off;
1002 in_len -= in_off;
1004 if (i >= prefix_len) {
1005 if (!in_len)
1006 return "./";
1007 else
1008 return in;
1011 strbuf_reset(sb);
1012 strbuf_grow(sb, in_len);
1014 while (i < prefix_len) {
1015 if (is_dir_sep(prefix[i])) {
1016 strbuf_addstr(sb, "../");
1017 while (is_dir_sep(prefix[i]))
1018 i++;
1019 continue;
1021 i++;
1023 if (!is_dir_sep(prefix[prefix_len - 1]))
1024 strbuf_addstr(sb, "../");
1026 strbuf_addstr(sb, in);
1028 return sb->buf;
1032 * A simpler implementation of relative_path
1034 * Get relative path by removing "prefix" from "in". This function
1035 * first appears in v1.5.6-1-g044bbbc, and makes git_dir shorter
1036 * to increase performance when traversing the path to work_tree.
1038 const char *remove_leading_path(const char *in, const char *prefix)
1040 static struct strbuf buf = STRBUF_INIT;
1041 int i = 0, j = 0;
1043 if (!prefix || !prefix[0])
1044 return in;
1045 while (prefix[i]) {
1046 if (is_dir_sep(prefix[i])) {
1047 if (!is_dir_sep(in[j]))
1048 return in;
1049 while (is_dir_sep(prefix[i]))
1050 i++;
1051 while (is_dir_sep(in[j]))
1052 j++;
1053 continue;
1054 } else if (in[j] != prefix[i]) {
1055 return in;
1057 i++;
1058 j++;
1060 if (
1061 /* "/foo" is a prefix of "/foo" */
1062 in[j] &&
1063 /* "/foo" is not a prefix of "/foobar" */
1064 !is_dir_sep(prefix[i-1]) && !is_dir_sep(in[j])
1066 return in;
1067 while (is_dir_sep(in[j]))
1068 j++;
1070 strbuf_reset(&buf);
1071 if (!in[j])
1072 strbuf_addstr(&buf, ".");
1073 else
1074 strbuf_addstr(&buf, in + j);
1075 return buf.buf;
1079 * It is okay if dst == src, but they should not overlap otherwise.
1080 * The "dst" buffer must be at least as long as "src"; normalizing may shrink
1081 * the size of the path, but will never grow it.
1083 * Performs the following normalizations on src, storing the result in dst:
1084 * - Ensures that components are separated by '/' (Windows only)
1085 * - Squashes sequences of '/' except "//server/share" on Windows
1086 * - Removes "." components.
1087 * - Removes ".." components, and the components the precede them.
1088 * Returns failure (non-zero) if a ".." component appears as first path
1089 * component anytime during the normalization. Otherwise, returns success (0).
1091 * Note that this function is purely textual. It does not follow symlinks,
1092 * verify the existence of the path, or make any system calls.
1094 * prefix_len != NULL is for a specific case of prefix_pathspec():
1095 * assume that src == dst and src[0..prefix_len-1] is already
1096 * normalized, any time "../" eats up to the prefix_len part,
1097 * prefix_len is reduced. In the end prefix_len is the remaining
1098 * prefix that has not been overridden by user pathspec.
1100 * NEEDSWORK: This function doesn't perform normalization w.r.t. trailing '/'.
1101 * For everything but the root folder itself, the normalized path should not
1102 * end with a '/', then the callers need to be fixed up accordingly.
1105 int normalize_path_copy_len(char *dst, const char *src, int *prefix_len)
1107 char *dst0;
1108 const char *end;
1111 * Copy initial part of absolute path: "/", "C:/", "//server/share/".
1113 end = src + offset_1st_component(src);
1114 while (src < end) {
1115 char c = *src++;
1116 if (is_dir_sep(c))
1117 c = '/';
1118 *dst++ = c;
1120 dst0 = dst;
1122 while (is_dir_sep(*src))
1123 src++;
1125 for (;;) {
1126 char c = *src;
1129 * A path component that begins with . could be
1130 * special:
1131 * (1) "." and ends -- ignore and terminate.
1132 * (2) "./" -- ignore them, eat slash and continue.
1133 * (3) ".." and ends -- strip one and terminate.
1134 * (4) "../" -- strip one, eat slash and continue.
1136 if (c == '.') {
1137 if (!src[1]) {
1138 /* (1) */
1139 src++;
1140 } else if (is_dir_sep(src[1])) {
1141 /* (2) */
1142 src += 2;
1143 while (is_dir_sep(*src))
1144 src++;
1145 continue;
1146 } else if (src[1] == '.') {
1147 if (!src[2]) {
1148 /* (3) */
1149 src += 2;
1150 goto up_one;
1151 } else if (is_dir_sep(src[2])) {
1152 /* (4) */
1153 src += 3;
1154 while (is_dir_sep(*src))
1155 src++;
1156 goto up_one;
1161 /* copy up to the next '/', and eat all '/' */
1162 while ((c = *src++) != '\0' && !is_dir_sep(c))
1163 *dst++ = c;
1164 if (is_dir_sep(c)) {
1165 *dst++ = '/';
1166 while (is_dir_sep(c))
1167 c = *src++;
1168 src--;
1169 } else if (!c)
1170 break;
1171 continue;
1173 up_one:
1175 * dst0..dst is prefix portion, and dst[-1] is '/';
1176 * go up one level.
1178 dst--; /* go to trailing '/' */
1179 if (dst <= dst0)
1180 return -1;
1181 /* Windows: dst[-1] cannot be backslash anymore */
1182 while (dst0 < dst && dst[-1] != '/')
1183 dst--;
1184 if (prefix_len && *prefix_len > dst - dst0)
1185 *prefix_len = dst - dst0;
1187 *dst = '\0';
1188 return 0;
1191 int normalize_path_copy(char *dst, const char *src)
1193 return normalize_path_copy_len(dst, src, NULL);
1197 * path = Canonical absolute path
1198 * prefixes = string_list containing normalized, absolute paths without
1199 * trailing slashes (except for the root directory, which is denoted by "/").
1201 * Determines, for each path in prefixes, whether the "prefix"
1202 * is an ancestor directory of path. Returns the length of the longest
1203 * ancestor directory, excluding any trailing slashes, or -1 if no prefix
1204 * is an ancestor. (Note that this means 0 is returned if prefixes is
1205 * ["/"].) "/foo" is not considered an ancestor of "/foobar". Directories
1206 * are not considered to be their own ancestors. path must be in a
1207 * canonical form: empty components, or "." or ".." components are not
1208 * allowed.
1210 int longest_ancestor_length(const char *path, struct string_list *prefixes)
1212 int i, max_len = -1;
1214 if (!strcmp(path, "/"))
1215 return -1;
1217 for (i = 0; i < prefixes->nr; i++) {
1218 const char *ceil = prefixes->items[i].string;
1219 int len = strlen(ceil);
1221 if (len == 1 && ceil[0] == '/')
1222 len = 0; /* root matches anything, with length 0 */
1223 else if (!strncmp(path, ceil, len) && path[len] == '/')
1224 ; /* match of length len */
1225 else
1226 continue; /* no match */
1228 if (len > max_len)
1229 max_len = len;
1232 return max_len;
1235 /* strip arbitrary amount of directory separators at end of path */
1236 static inline int chomp_trailing_dir_sep(const char *path, int len)
1238 while (len && is_dir_sep(path[len - 1]))
1239 len--;
1240 return len;
1244 * If path ends with suffix (complete path components), returns the offset of
1245 * the last character in the path before the suffix (sans trailing directory
1246 * separators), and -1 otherwise.
1248 static ssize_t stripped_path_suffix_offset(const char *path, const char *suffix)
1250 int path_len = strlen(path), suffix_len = strlen(suffix);
1252 while (suffix_len) {
1253 if (!path_len)
1254 return -1;
1256 if (is_dir_sep(path[path_len - 1])) {
1257 if (!is_dir_sep(suffix[suffix_len - 1]))
1258 return -1;
1259 path_len = chomp_trailing_dir_sep(path, path_len);
1260 suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
1262 else if (path[--path_len] != suffix[--suffix_len])
1263 return -1;
1266 if (path_len && !is_dir_sep(path[path_len - 1]))
1267 return -1;
1268 return chomp_trailing_dir_sep(path, path_len);
1272 * Returns true if the path ends with components, considering only complete path
1273 * components, and false otherwise.
1275 int ends_with_path_components(const char *path, const char *components)
1277 return stripped_path_suffix_offset(path, components) != -1;
1281 * If path ends with suffix (complete path components), returns the
1282 * part before suffix (sans trailing directory separators).
1283 * Otherwise returns NULL.
1285 char *strip_path_suffix(const char *path, const char *suffix)
1287 ssize_t offset = stripped_path_suffix_offset(path, suffix);
1289 return offset == -1 ? NULL : xstrndup(path, offset);
1292 int daemon_avoid_alias(const char *p)
1294 int sl, ndot;
1297 * This resurrects the belts and suspenders paranoia check by HPA
1298 * done in <435560F7.4080006@zytor.com> thread, now enter_repo()
1299 * does not do getcwd() based path canonicalization.
1301 * sl becomes true immediately after seeing '/' and continues to
1302 * be true as long as dots continue after that without intervening
1303 * non-dot character.
1305 if (!p || (*p != '/' && *p != '~'))
1306 return -1;
1307 sl = 1; ndot = 0;
1308 p++;
1310 while (1) {
1311 char ch = *p++;
1312 if (sl) {
1313 if (ch == '.')
1314 ndot++;
1315 else if (ch == '/') {
1316 if (ndot < 3)
1317 /* reject //, /./ and /../ */
1318 return -1;
1319 ndot = 0;
1321 else if (ch == 0) {
1322 if (0 < ndot && ndot < 3)
1323 /* reject /.$ and /..$ */
1324 return -1;
1325 return 0;
1327 else
1328 sl = ndot = 0;
1330 else if (ch == 0)
1331 return 0;
1332 else if (ch == '/') {
1333 sl = 1;
1334 ndot = 0;
1340 * On NTFS, we need to be careful to disallow certain synonyms of the `.git/`
1341 * directory:
1343 * - For historical reasons, file names that end in spaces or periods are
1344 * automatically trimmed. Therefore, `.git . . ./` is a valid way to refer
1345 * to `.git/`.
1347 * - For other historical reasons, file names that do not conform to the 8.3
1348 * format (up to eight characters for the basename, three for the file
1349 * extension, certain characters not allowed such as `+`, etc) are associated
1350 * with a so-called "short name", at least on the `C:` drive by default.
1351 * Which means that `git~1/` is a valid way to refer to `.git/`.
1353 * Note: Technically, `.git/` could receive the short name `git~2` if the
1354 * short name `git~1` were already used. In Git, however, we guarantee that
1355 * `.git` is the first item in a directory, therefore it will be associated
1356 * with the short name `git~1` (unless short names are disabled).
1358 * - For yet other historical reasons, NTFS supports so-called "Alternate Data
1359 * Streams", i.e. metadata associated with a given file, referred to via
1360 * `<filename>:<stream-name>:<stream-type>`. There exists a default stream
1361 * type for directories, allowing `.git/` to be accessed via
1362 * `.git::$INDEX_ALLOCATION/`.
1364 * When this function returns 1, it indicates that the specified file/directory
1365 * name refers to a `.git` file or directory, or to any of these synonyms, and
1366 * Git should therefore not track it.
1368 * For performance reasons, _all_ Alternate Data Streams of `.git/` are
1369 * forbidden, not just `::$INDEX_ALLOCATION`.
1371 * This function is intended to be used by `git fsck` even on platforms where
1372 * the backslash is a regular filename character, therefore it needs to handle
1373 * backlash characters in the provided `name` specially: they are interpreted
1374 * as directory separators.
1376 int is_ntfs_dotgit(const char *name)
1378 char c;
1381 * Note that when we don't find `.git` or `git~1` we end up with `name`
1382 * advanced partway through the string. That's okay, though, as we
1383 * return immediately in those cases, without looking at `name` any
1384 * further.
1386 c = *(name++);
1387 if (c == '.') {
1388 /* .git */
1389 if (((c = *(name++)) != 'g' && c != 'G') ||
1390 ((c = *(name++)) != 'i' && c != 'I') ||
1391 ((c = *(name++)) != 't' && c != 'T'))
1392 return 0;
1393 } else if (c == 'g' || c == 'G') {
1394 /* git ~1 */
1395 if (((c = *(name++)) != 'i' && c != 'I') ||
1396 ((c = *(name++)) != 't' && c != 'T') ||
1397 *(name++) != '~' ||
1398 *(name++) != '1')
1399 return 0;
1400 } else
1401 return 0;
1403 for (;;) {
1404 c = *(name++);
1405 if (!c || c == '\\' || c == '/' || c == ':')
1406 return 1;
1407 if (c != '.' && c != ' ')
1408 return 0;
1412 static int is_ntfs_dot_generic(const char *name,
1413 const char *dotgit_name,
1414 size_t len,
1415 const char *dotgit_ntfs_shortname_prefix)
1417 int saw_tilde;
1418 size_t i;
1420 if ((name[0] == '.' && !strncasecmp(name + 1, dotgit_name, len))) {
1421 i = len + 1;
1422 only_spaces_and_periods:
1423 for (;;) {
1424 char c = name[i++];
1425 if (!c || c == ':')
1426 return 1;
1427 if (c != ' ' && c != '.')
1428 return 0;
1433 * Is it a regular NTFS short name, i.e. shortened to 6 characters,
1434 * followed by ~1, ... ~4?
1436 if (!strncasecmp(name, dotgit_name, 6) && name[6] == '~' &&
1437 name[7] >= '1' && name[7] <= '4') {
1438 i = 8;
1439 goto only_spaces_and_periods;
1443 * Is it a fall-back NTFS short name (for details, see
1444 * https://en.wikipedia.org/wiki/8.3_filename?
1446 for (i = 0, saw_tilde = 0; i < 8; i++)
1447 if (name[i] == '\0')
1448 return 0;
1449 else if (saw_tilde) {
1450 if (name[i] < '0' || name[i] > '9')
1451 return 0;
1452 } else if (name[i] == '~') {
1453 if (name[++i] < '1' || name[i] > '9')
1454 return 0;
1455 saw_tilde = 1;
1456 } else if (i >= 6)
1457 return 0;
1458 else if (name[i] & 0x80) {
1460 * We know our needles contain only ASCII, so we clamp
1461 * here to make the results of tolower() sane.
1463 return 0;
1464 } else if (tolower(name[i]) != dotgit_ntfs_shortname_prefix[i])
1465 return 0;
1467 goto only_spaces_and_periods;
1471 * Inline helper to make sure compiler resolves strlen() on literals at
1472 * compile time.
1474 static inline int is_ntfs_dot_str(const char *name, const char *dotgit_name,
1475 const char *dotgit_ntfs_shortname_prefix)
1477 return is_ntfs_dot_generic(name, dotgit_name, strlen(dotgit_name),
1478 dotgit_ntfs_shortname_prefix);
1481 int is_ntfs_dotgitmodules(const char *name)
1483 return is_ntfs_dot_str(name, "gitmodules", "gi7eba");
1486 int is_ntfs_dotgitignore(const char *name)
1488 return is_ntfs_dot_str(name, "gitignore", "gi250a");
1491 int is_ntfs_dotgitattributes(const char *name)
1493 return is_ntfs_dot_str(name, "gitattributes", "gi7d29");
1496 int looks_like_command_line_option(const char *str)
1498 return str && str[0] == '-';
1501 char *xdg_config_home(const char *filename)
1503 const char *home, *config_home;
1505 assert(filename);
1506 config_home = getenv("XDG_CONFIG_HOME");
1507 if (config_home && *config_home)
1508 return mkpathdup("%s/git/%s", config_home, filename);
1510 home = getenv("HOME");
1511 if (home)
1512 return mkpathdup("%s/.config/git/%s", home, filename);
1513 return NULL;
1516 char *xdg_cache_home(const char *filename)
1518 const char *home, *cache_home;
1520 assert(filename);
1521 cache_home = getenv("XDG_CACHE_HOME");
1522 if (cache_home && *cache_home)
1523 return mkpathdup("%s/git/%s", cache_home, filename);
1525 home = getenv("HOME");
1526 if (home)
1527 return mkpathdup("%s/.cache/git/%s", home, filename);
1528 return NULL;
1531 REPO_GIT_PATH_FUNC(cherry_pick_head, "CHERRY_PICK_HEAD")
1532 REPO_GIT_PATH_FUNC(revert_head, "REVERT_HEAD")
1533 REPO_GIT_PATH_FUNC(squash_msg, "SQUASH_MSG")
1534 REPO_GIT_PATH_FUNC(merge_msg, "MERGE_MSG")
1535 REPO_GIT_PATH_FUNC(merge_rr, "MERGE_RR")
1536 REPO_GIT_PATH_FUNC(merge_mode, "MERGE_MODE")
1537 REPO_GIT_PATH_FUNC(merge_head, "MERGE_HEAD")
1538 REPO_GIT_PATH_FUNC(merge_autostash, "MERGE_AUTOSTASH")
1539 REPO_GIT_PATH_FUNC(fetch_head, "FETCH_HEAD")
1540 REPO_GIT_PATH_FUNC(shallow, "shallow")