transport-helper: drop read/write errno checks
[git.git] / path.c
blobdc3294c71e1e72ae2aae9164c790e27d1237e956
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"
15 static int get_st_mode_bits(const char *path, int *mode)
17 struct stat st;
18 if (lstat(path, &st) < 0)
19 return -1;
20 *mode = st.st_mode;
21 return 0;
24 static char bad_path[] = "/bad-path/";
26 static struct strbuf *get_pathname(void)
28 static struct strbuf pathname_array[4] = {
29 STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
31 static int index;
32 struct strbuf *sb = &pathname_array[index];
33 index = (index + 1) % ARRAY_SIZE(pathname_array);
34 strbuf_reset(sb);
35 return sb;
38 static const char *cleanup_path(const char *path)
40 /* Clean it up */
41 if (skip_prefix(path, "./", &path)) {
42 while (*path == '/')
43 path++;
45 return path;
48 static void strbuf_cleanup_path(struct strbuf *sb)
50 const char *path = cleanup_path(sb->buf);
51 if (path > sb->buf)
52 strbuf_remove(sb, 0, path - sb->buf);
55 char *mksnpath(char *buf, size_t n, const char *fmt, ...)
57 va_list args;
58 unsigned len;
60 va_start(args, fmt);
61 len = vsnprintf(buf, n, fmt, args);
62 va_end(args);
63 if (len >= n) {
64 strlcpy(buf, bad_path, n);
65 return buf;
67 return (char *)cleanup_path(buf);
70 static int dir_prefix(const char *buf, const char *dir)
72 int len = strlen(dir);
73 return !strncmp(buf, dir, len) &&
74 (is_dir_sep(buf[len]) || buf[len] == '\0');
77 /* $buf =~ m|$dir/+$file| but without regex */
78 static int is_dir_file(const char *buf, const char *dir, const char *file)
80 int len = strlen(dir);
81 if (strncmp(buf, dir, len) || !is_dir_sep(buf[len]))
82 return 0;
83 while (is_dir_sep(buf[len]))
84 len++;
85 return !strcmp(buf + len, file);
88 static void replace_dir(struct strbuf *buf, int len, const char *newdir)
90 int newlen = strlen(newdir);
91 int need_sep = (buf->buf[len] && !is_dir_sep(buf->buf[len])) &&
92 !is_dir_sep(newdir[newlen - 1]);
93 if (need_sep)
94 len--; /* keep one char, to be replaced with '/' */
95 strbuf_splice(buf, 0, len, newdir, newlen);
96 if (need_sep)
97 buf->buf[newlen] = '/';
100 struct common_dir {
101 /* Not considered garbage for report_linked_checkout_garbage */
102 unsigned ignore_garbage:1;
103 unsigned is_dir:1;
104 /* Not common even though its parent is */
105 unsigned exclude:1;
106 const char *dirname;
109 static struct common_dir common_list[] = {
110 { 0, 1, 0, "branches" },
111 { 0, 1, 0, "common" },
112 { 0, 1, 0, "hooks" },
113 { 0, 1, 0, "info" },
114 { 0, 0, 1, "info/sparse-checkout" },
115 { 1, 1, 0, "logs" },
116 { 1, 1, 1, "logs/HEAD" },
117 { 0, 1, 1, "logs/refs/bisect" },
118 { 0, 1, 0, "lost-found" },
119 { 0, 1, 0, "objects" },
120 { 0, 1, 0, "refs" },
121 { 0, 1, 1, "refs/bisect" },
122 { 0, 1, 1, "refs/worktree" },
123 { 0, 1, 0, "remotes" },
124 { 0, 1, 0, "worktrees" },
125 { 0, 1, 0, "rr-cache" },
126 { 0, 1, 0, "svn" },
127 { 0, 0, 0, "config" },
128 { 1, 0, 0, "gc.pid" },
129 { 0, 0, 0, "packed-refs" },
130 { 0, 0, 0, "shallow" },
131 { 0, 0, 0, NULL }
135 * A compressed trie. A trie node consists of zero or more characters that
136 * are common to all elements with this prefix, optionally followed by some
137 * children. If value is not NULL, the trie node is a terminal node.
139 * For example, consider the following set of strings:
140 * abc
141 * def
142 * definite
143 * definition
145 * The trie would look like:
146 * root: len = 0, children a and d non-NULL, value = NULL.
147 * a: len = 2, contents = bc, value = (data for "abc")
148 * d: len = 2, contents = ef, children i non-NULL, value = (data for "def")
149 * i: len = 3, contents = nit, children e and i non-NULL, value = NULL
150 * e: len = 0, children all NULL, value = (data for "definite")
151 * i: len = 2, contents = on, children all NULL,
152 * value = (data for "definition")
154 struct trie {
155 struct trie *children[256];
156 int len;
157 char *contents;
158 void *value;
161 static struct trie *make_trie_node(const char *key, void *value)
163 struct trie *new_node = xcalloc(1, sizeof(*new_node));
164 new_node->len = strlen(key);
165 if (new_node->len) {
166 new_node->contents = xmalloc(new_node->len);
167 memcpy(new_node->contents, key, new_node->len);
169 new_node->value = value;
170 return new_node;
174 * Add a key/value pair to a trie. The key is assumed to be \0-terminated.
175 * If there was an existing value for this key, return it.
177 static void *add_to_trie(struct trie *root, const char *key, void *value)
179 struct trie *child;
180 void *old;
181 int i;
183 if (!*key) {
184 /* we have reached the end of the key */
185 old = root->value;
186 root->value = value;
187 return old;
190 for (i = 0; i < root->len; i++) {
191 if (root->contents[i] == key[i])
192 continue;
195 * Split this node: child will contain this node's
196 * existing children.
198 child = xmalloc(sizeof(*child));
199 memcpy(child->children, root->children, sizeof(root->children));
201 child->len = root->len - i - 1;
202 if (child->len) {
203 child->contents = xstrndup(root->contents + i + 1,
204 child->len);
206 child->value = root->value;
207 root->value = NULL;
208 root->len = i;
210 memset(root->children, 0, sizeof(root->children));
211 root->children[(unsigned char)root->contents[i]] = child;
213 /* This is the newly-added child. */
214 root->children[(unsigned char)key[i]] =
215 make_trie_node(key + i + 1, value);
216 return NULL;
219 /* We have matched the entire compressed section */
220 if (key[i]) {
221 child = root->children[(unsigned char)key[root->len]];
222 if (child) {
223 return add_to_trie(child, key + root->len + 1, value);
224 } else {
225 child = make_trie_node(key + root->len + 1, value);
226 root->children[(unsigned char)key[root->len]] = child;
227 return NULL;
231 old = root->value;
232 root->value = value;
233 return old;
236 typedef int (*match_fn)(const char *unmatched, void *data, void *baton);
239 * Search a trie for some key. Find the longest /-or-\0-terminated
240 * prefix of the key for which the trie contains a value. Call fn
241 * with the unmatched portion of the key and the found value, and
242 * return its return value. If there is no such prefix, return -1.
244 * The key is partially normalized: consecutive slashes are skipped.
246 * For example, consider the trie containing only [refs,
247 * refs/worktree] (both with values).
249 * | key | unmatched | val from node | return value |
250 * |-----------------|------------|---------------|--------------|
251 * | a | not called | n/a | -1 |
252 * | refs | \0 | refs | as per fn |
253 * | refs/ | / | refs | as per fn |
254 * | refs/w | /w | refs | as per fn |
255 * | refs/worktree | \0 | refs/worktree | as per fn |
256 * | refs/worktree/ | / | refs/worktree | as per fn |
257 * | refs/worktree/a | /a | refs/worktree | as per fn |
258 * |-----------------|------------|---------------|--------------|
261 static int trie_find(struct trie *root, const char *key, match_fn fn,
262 void *baton)
264 int i;
265 int result;
266 struct trie *child;
268 if (!*key) {
269 /* we have reached the end of the key */
270 if (root->value && !root->len)
271 return fn(key, root->value, baton);
272 else
273 return -1;
276 for (i = 0; i < root->len; i++) {
277 /* Partial path normalization: skip consecutive slashes. */
278 if (key[i] == '/' && key[i+1] == '/') {
279 key++;
280 continue;
282 if (root->contents[i] != key[i])
283 return -1;
286 /* Matched the entire compressed section */
287 key += i;
288 if (!*key)
289 /* End of key */
290 return fn(key, root->value, baton);
292 /* Partial path normalization: skip consecutive slashes */
293 while (key[0] == '/' && key[1] == '/')
294 key++;
296 child = root->children[(unsigned char)*key];
297 if (child)
298 result = trie_find(child, key + 1, fn, baton);
299 else
300 result = -1;
302 if (result >= 0 || (*key != '/' && *key != 0))
303 return result;
304 if (root->value)
305 return fn(key, root->value, baton);
306 else
307 return -1;
310 static struct trie common_trie;
311 static int common_trie_done_setup;
313 static void init_common_trie(void)
315 struct common_dir *p;
317 if (common_trie_done_setup)
318 return;
320 for (p = common_list; p->dirname; p++)
321 add_to_trie(&common_trie, p->dirname, p);
323 common_trie_done_setup = 1;
327 * Helper function for update_common_dir: returns 1 if the dir
328 * prefix is common.
330 static int check_common(const char *unmatched, void *value, void *baton)
332 struct common_dir *dir = value;
334 if (!dir)
335 return 0;
337 if (dir->is_dir && (unmatched[0] == 0 || unmatched[0] == '/'))
338 return !dir->exclude;
340 if (!dir->is_dir && unmatched[0] == 0)
341 return !dir->exclude;
343 return 0;
346 static void update_common_dir(struct strbuf *buf, int git_dir_len,
347 const char *common_dir)
349 char *base = buf->buf + git_dir_len;
350 init_common_trie();
351 if (trie_find(&common_trie, base, check_common, NULL) > 0)
352 replace_dir(buf, git_dir_len, common_dir);
355 void report_linked_checkout_garbage(void)
357 struct strbuf sb = STRBUF_INIT;
358 const struct common_dir *p;
359 int len;
361 if (!the_repository->different_commondir)
362 return;
363 strbuf_addf(&sb, "%s/", get_git_dir());
364 len = sb.len;
365 for (p = common_list; p->dirname; p++) {
366 const char *path = p->dirname;
367 if (p->ignore_garbage)
368 continue;
369 strbuf_setlen(&sb, len);
370 strbuf_addstr(&sb, path);
371 if (file_exists(sb.buf))
372 report_garbage(PACKDIR_FILE_GARBAGE, sb.buf);
374 strbuf_release(&sb);
377 static void adjust_git_path(const struct repository *repo,
378 struct strbuf *buf, int git_dir_len)
380 const char *base = buf->buf + git_dir_len;
381 if (is_dir_file(base, "info", "grafts"))
382 strbuf_splice(buf, 0, buf->len,
383 repo->graft_file, strlen(repo->graft_file));
384 else if (!strcmp(base, "index"))
385 strbuf_splice(buf, 0, buf->len,
386 repo->index_file, strlen(repo->index_file));
387 else if (dir_prefix(base, "objects"))
388 replace_dir(buf, git_dir_len + 7, repo->objects->objectdir);
389 else if (git_hooks_path && dir_prefix(base, "hooks"))
390 replace_dir(buf, git_dir_len + 5, git_hooks_path);
391 else if (repo->different_commondir)
392 update_common_dir(buf, git_dir_len, repo->commondir);
395 static void strbuf_worktree_gitdir(struct strbuf *buf,
396 const struct repository *repo,
397 const struct worktree *wt)
399 if (!wt)
400 strbuf_addstr(buf, repo->gitdir);
401 else if (!wt->id)
402 strbuf_addstr(buf, repo->commondir);
403 else
404 strbuf_git_common_path(buf, repo, "worktrees/%s", wt->id);
407 static void do_git_path(const struct repository *repo,
408 const struct worktree *wt, struct strbuf *buf,
409 const char *fmt, va_list args)
411 int gitdir_len;
412 strbuf_worktree_gitdir(buf, repo, wt);
413 if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
414 strbuf_addch(buf, '/');
415 gitdir_len = buf->len;
416 strbuf_vaddf(buf, fmt, args);
417 if (!wt)
418 adjust_git_path(repo, buf, gitdir_len);
419 strbuf_cleanup_path(buf);
422 char *repo_git_path(const struct repository *repo,
423 const char *fmt, ...)
425 struct strbuf path = STRBUF_INIT;
426 va_list args;
427 va_start(args, fmt);
428 do_git_path(repo, NULL, &path, fmt, args);
429 va_end(args);
430 return strbuf_detach(&path, NULL);
433 void strbuf_repo_git_path(struct strbuf *sb,
434 const struct repository *repo,
435 const char *fmt, ...)
437 va_list args;
438 va_start(args, fmt);
439 do_git_path(repo, NULL, sb, fmt, args);
440 va_end(args);
443 char *git_path_buf(struct strbuf *buf, const char *fmt, ...)
445 va_list args;
446 strbuf_reset(buf);
447 va_start(args, fmt);
448 do_git_path(the_repository, NULL, buf, fmt, args);
449 va_end(args);
450 return buf->buf;
453 void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
455 va_list args;
456 va_start(args, fmt);
457 do_git_path(the_repository, NULL, sb, fmt, args);
458 va_end(args);
461 const char *git_path(const char *fmt, ...)
463 struct strbuf *pathname = get_pathname();
464 va_list args;
465 va_start(args, fmt);
466 do_git_path(the_repository, NULL, pathname, fmt, args);
467 va_end(args);
468 return pathname->buf;
471 char *git_pathdup(const char *fmt, ...)
473 struct strbuf path = STRBUF_INIT;
474 va_list args;
475 va_start(args, fmt);
476 do_git_path(the_repository, NULL, &path, fmt, args);
477 va_end(args);
478 return strbuf_detach(&path, NULL);
481 char *mkpathdup(const char *fmt, ...)
483 struct strbuf sb = STRBUF_INIT;
484 va_list args;
485 va_start(args, fmt);
486 strbuf_vaddf(&sb, fmt, args);
487 va_end(args);
488 strbuf_cleanup_path(&sb);
489 return strbuf_detach(&sb, NULL);
492 const char *mkpath(const char *fmt, ...)
494 va_list args;
495 struct strbuf *pathname = get_pathname();
496 va_start(args, fmt);
497 strbuf_vaddf(pathname, fmt, args);
498 va_end(args);
499 return cleanup_path(pathname->buf);
502 const char *worktree_git_path(const struct worktree *wt, const char *fmt, ...)
504 struct strbuf *pathname = get_pathname();
505 va_list args;
506 va_start(args, fmt);
507 do_git_path(the_repository, wt, pathname, fmt, args);
508 va_end(args);
509 return pathname->buf;
512 static void do_worktree_path(const struct repository *repo,
513 struct strbuf *buf,
514 const char *fmt, va_list args)
516 strbuf_addstr(buf, repo->worktree);
517 if(buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
518 strbuf_addch(buf, '/');
520 strbuf_vaddf(buf, fmt, args);
521 strbuf_cleanup_path(buf);
524 char *repo_worktree_path(const struct repository *repo, const char *fmt, ...)
526 struct strbuf path = STRBUF_INIT;
527 va_list args;
529 if (!repo->worktree)
530 return NULL;
532 va_start(args, fmt);
533 do_worktree_path(repo, &path, fmt, args);
534 va_end(args);
536 return strbuf_detach(&path, NULL);
539 void strbuf_repo_worktree_path(struct strbuf *sb,
540 const struct repository *repo,
541 const char *fmt, ...)
543 va_list args;
545 if (!repo->worktree)
546 return;
548 va_start(args, fmt);
549 do_worktree_path(repo, sb, fmt, args);
550 va_end(args);
553 /* Returns 0 on success, negative on failure. */
554 static int do_submodule_path(struct strbuf *buf, const char *path,
555 const char *fmt, va_list args)
557 struct strbuf git_submodule_common_dir = STRBUF_INIT;
558 struct strbuf git_submodule_dir = STRBUF_INIT;
559 int ret;
561 ret = submodule_to_gitdir(&git_submodule_dir, path);
562 if (ret)
563 goto cleanup;
565 strbuf_complete(&git_submodule_dir, '/');
566 strbuf_addbuf(buf, &git_submodule_dir);
567 strbuf_vaddf(buf, fmt, args);
569 if (get_common_dir_noenv(&git_submodule_common_dir, git_submodule_dir.buf))
570 update_common_dir(buf, git_submodule_dir.len, git_submodule_common_dir.buf);
572 strbuf_cleanup_path(buf);
574 cleanup:
575 strbuf_release(&git_submodule_dir);
576 strbuf_release(&git_submodule_common_dir);
577 return ret;
580 char *git_pathdup_submodule(const char *path, const char *fmt, ...)
582 int err;
583 va_list args;
584 struct strbuf buf = STRBUF_INIT;
585 va_start(args, fmt);
586 err = do_submodule_path(&buf, path, fmt, args);
587 va_end(args);
588 if (err) {
589 strbuf_release(&buf);
590 return NULL;
592 return strbuf_detach(&buf, NULL);
595 int strbuf_git_path_submodule(struct strbuf *buf, const char *path,
596 const char *fmt, ...)
598 int err;
599 va_list args;
600 va_start(args, fmt);
601 err = do_submodule_path(buf, path, fmt, args);
602 va_end(args);
604 return err;
607 static void do_git_common_path(const struct repository *repo,
608 struct strbuf *buf,
609 const char *fmt,
610 va_list args)
612 strbuf_addstr(buf, repo->commondir);
613 if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
614 strbuf_addch(buf, '/');
615 strbuf_vaddf(buf, fmt, args);
616 strbuf_cleanup_path(buf);
619 const char *git_common_path(const char *fmt, ...)
621 struct strbuf *pathname = get_pathname();
622 va_list args;
623 va_start(args, fmt);
624 do_git_common_path(the_repository, pathname, fmt, args);
625 va_end(args);
626 return pathname->buf;
629 void strbuf_git_common_path(struct strbuf *sb,
630 const struct repository *repo,
631 const char *fmt, ...)
633 va_list args;
634 va_start(args, fmt);
635 do_git_common_path(repo, sb, fmt, args);
636 va_end(args);
639 int validate_headref(const char *path)
641 struct stat st;
642 char buffer[256];
643 const char *refname;
644 struct object_id oid;
645 int fd;
646 ssize_t len;
648 if (lstat(path, &st) < 0)
649 return -1;
651 /* Make sure it is a "refs/.." symlink */
652 if (S_ISLNK(st.st_mode)) {
653 len = readlink(path, buffer, sizeof(buffer)-1);
654 if (len >= 5 && !memcmp("refs/", buffer, 5))
655 return 0;
656 return -1;
660 * Anything else, just open it and try to see if it is a symbolic ref.
662 fd = open(path, O_RDONLY);
663 if (fd < 0)
664 return -1;
665 len = read_in_full(fd, buffer, sizeof(buffer)-1);
666 close(fd);
668 if (len < 0)
669 return -1;
670 buffer[len] = '\0';
673 * Is it a symbolic ref?
675 if (skip_prefix(buffer, "ref:", &refname)) {
676 while (isspace(*refname))
677 refname++;
678 if (starts_with(refname, "refs/"))
679 return 0;
683 * Is this a detached HEAD?
685 if (!get_oid_hex(buffer, &oid))
686 return 0;
688 return -1;
691 static struct passwd *getpw_str(const char *username, size_t len)
693 struct passwd *pw;
694 char *username_z = xmemdupz(username, len);
695 pw = getpwnam(username_z);
696 free(username_z);
697 return pw;
701 * Return a string with ~ and ~user expanded via getpw*. If buf != NULL,
702 * then it is a newly allocated string. Returns NULL on getpw failure or
703 * if path is NULL.
705 * If real_home is true, real_path($HOME) is used in the expansion.
707 char *expand_user_path(const char *path, int real_home)
709 struct strbuf user_path = STRBUF_INIT;
710 const char *to_copy = path;
712 if (path == NULL)
713 goto return_null;
714 if (path[0] == '~') {
715 const char *first_slash = strchrnul(path, '/');
716 const char *username = path + 1;
717 size_t username_len = first_slash - username;
718 if (username_len == 0) {
719 const char *home = getenv("HOME");
720 if (!home)
721 goto return_null;
722 if (real_home)
723 strbuf_add_real_path(&user_path, home);
724 else
725 strbuf_addstr(&user_path, home);
726 #ifdef GIT_WINDOWS_NATIVE
727 convert_slashes(user_path.buf);
728 #endif
729 } else {
730 struct passwd *pw = getpw_str(username, username_len);
731 if (!pw)
732 goto return_null;
733 strbuf_addstr(&user_path, pw->pw_dir);
735 to_copy = first_slash;
737 strbuf_addstr(&user_path, to_copy);
738 return strbuf_detach(&user_path, NULL);
739 return_null:
740 strbuf_release(&user_path);
741 return NULL;
745 * First, one directory to try is determined by the following algorithm.
747 * (0) If "strict" is given, the path is used as given and no DWIM is
748 * done. Otherwise:
749 * (1) "~/path" to mean path under the running user's home directory;
750 * (2) "~user/path" to mean path under named user's home directory;
751 * (3) "relative/path" to mean cwd relative directory; or
752 * (4) "/absolute/path" to mean absolute directory.
754 * Unless "strict" is given, we check "%s/.git", "%s", "%s.git/.git", "%s.git"
755 * in this order. We select the first one that is a valid git repository, and
756 * chdir() to it. If none match, or we fail to chdir, we return NULL.
758 * If all goes well, we return the directory we used to chdir() (but
759 * before ~user is expanded), avoiding getcwd() resolving symbolic
760 * links. User relative paths are also returned as they are given,
761 * except DWIM suffixing.
763 const char *enter_repo(const char *path, int strict)
765 static struct strbuf validated_path = STRBUF_INIT;
766 static struct strbuf used_path = STRBUF_INIT;
768 if (!path)
769 return NULL;
771 if (!strict) {
772 static const char *suffix[] = {
773 "/.git", "", ".git/.git", ".git", NULL,
775 const char *gitfile;
776 int len = strlen(path);
777 int i;
778 while ((1 < len) && (path[len-1] == '/'))
779 len--;
782 * We can handle arbitrary-sized buffers, but this remains as a
783 * sanity check on untrusted input.
785 if (PATH_MAX <= len)
786 return NULL;
788 strbuf_reset(&used_path);
789 strbuf_reset(&validated_path);
790 strbuf_add(&used_path, path, len);
791 strbuf_add(&validated_path, path, len);
793 if (used_path.buf[0] == '~') {
794 char *newpath = expand_user_path(used_path.buf, 0);
795 if (!newpath)
796 return NULL;
797 strbuf_attach(&used_path, newpath, strlen(newpath),
798 strlen(newpath));
800 for (i = 0; suffix[i]; i++) {
801 struct stat st;
802 size_t baselen = used_path.len;
803 strbuf_addstr(&used_path, suffix[i]);
804 if (!stat(used_path.buf, &st) &&
805 (S_ISREG(st.st_mode) ||
806 (S_ISDIR(st.st_mode) && is_git_directory(used_path.buf)))) {
807 strbuf_addstr(&validated_path, suffix[i]);
808 break;
810 strbuf_setlen(&used_path, baselen);
812 if (!suffix[i])
813 return NULL;
814 gitfile = read_gitfile(used_path.buf);
815 if (gitfile) {
816 strbuf_reset(&used_path);
817 strbuf_addstr(&used_path, gitfile);
819 if (chdir(used_path.buf))
820 return NULL;
821 path = validated_path.buf;
823 else {
824 const char *gitfile = read_gitfile(path);
825 if (gitfile)
826 path = gitfile;
827 if (chdir(path))
828 return NULL;
831 if (is_git_directory(".")) {
832 set_git_dir(".");
833 check_repository_format();
834 return path;
837 return NULL;
840 static int calc_shared_perm(int mode)
842 int tweak;
844 if (get_shared_repository() < 0)
845 tweak = -get_shared_repository();
846 else
847 tweak = get_shared_repository();
849 if (!(mode & S_IWUSR))
850 tweak &= ~0222;
851 if (mode & S_IXUSR)
852 /* Copy read bits to execute bits */
853 tweak |= (tweak & 0444) >> 2;
854 if (get_shared_repository() < 0)
855 mode = (mode & ~0777) | tweak;
856 else
857 mode |= tweak;
859 return mode;
863 int adjust_shared_perm(const char *path)
865 int old_mode, new_mode;
867 if (!get_shared_repository())
868 return 0;
869 if (get_st_mode_bits(path, &old_mode) < 0)
870 return -1;
872 new_mode = calc_shared_perm(old_mode);
873 if (S_ISDIR(old_mode)) {
874 /* Copy read bits to execute bits */
875 new_mode |= (new_mode & 0444) >> 2;
876 new_mode |= FORCE_DIR_SET_GID;
879 if (((old_mode ^ new_mode) & ~S_IFMT) &&
880 chmod(path, (new_mode & ~S_IFMT)) < 0)
881 return -2;
882 return 0;
885 void safe_create_dir(const char *dir, int share)
887 if (mkdir(dir, 0777) < 0) {
888 if (errno != EEXIST) {
889 perror(dir);
890 exit(1);
893 else if (share && adjust_shared_perm(dir))
894 die(_("Could not make %s writable by group"), dir);
897 static int have_same_root(const char *path1, const char *path2)
899 int is_abs1, is_abs2;
901 is_abs1 = is_absolute_path(path1);
902 is_abs2 = is_absolute_path(path2);
903 return (is_abs1 && is_abs2 && tolower(path1[0]) == tolower(path2[0])) ||
904 (!is_abs1 && !is_abs2);
908 * Give path as relative to prefix.
910 * The strbuf may or may not be used, so do not assume it contains the
911 * returned path.
913 const char *relative_path(const char *in, const char *prefix,
914 struct strbuf *sb)
916 int in_len = in ? strlen(in) : 0;
917 int prefix_len = prefix ? strlen(prefix) : 0;
918 int in_off = 0;
919 int prefix_off = 0;
920 int i = 0, j = 0;
922 if (!in_len)
923 return "./";
924 else if (!prefix_len)
925 return in;
927 if (have_same_root(in, prefix))
928 /* bypass dos_drive, for "c:" is identical to "C:" */
929 i = j = has_dos_drive_prefix(in);
930 else {
931 return in;
934 while (i < prefix_len && j < in_len && prefix[i] == in[j]) {
935 if (is_dir_sep(prefix[i])) {
936 while (is_dir_sep(prefix[i]))
937 i++;
938 while (is_dir_sep(in[j]))
939 j++;
940 prefix_off = i;
941 in_off = j;
942 } else {
943 i++;
944 j++;
948 if (
949 /* "prefix" seems like prefix of "in" */
950 i >= prefix_len &&
952 * but "/foo" is not a prefix of "/foobar"
953 * (i.e. prefix not end with '/')
955 prefix_off < prefix_len) {
956 if (j >= in_len) {
957 /* in="/a/b", prefix="/a/b" */
958 in_off = in_len;
959 } else if (is_dir_sep(in[j])) {
960 /* in="/a/b/c", prefix="/a/b" */
961 while (is_dir_sep(in[j]))
962 j++;
963 in_off = j;
964 } else {
965 /* in="/a/bbb/c", prefix="/a/b" */
966 i = prefix_off;
968 } else if (
969 /* "in" is short than "prefix" */
970 j >= in_len &&
971 /* "in" not end with '/' */
972 in_off < in_len) {
973 if (is_dir_sep(prefix[i])) {
974 /* in="/a/b", prefix="/a/b/c/" */
975 while (is_dir_sep(prefix[i]))
976 i++;
977 in_off = in_len;
980 in += in_off;
981 in_len -= in_off;
983 if (i >= prefix_len) {
984 if (!in_len)
985 return "./";
986 else
987 return in;
990 strbuf_reset(sb);
991 strbuf_grow(sb, in_len);
993 while (i < prefix_len) {
994 if (is_dir_sep(prefix[i])) {
995 strbuf_addstr(sb, "../");
996 while (is_dir_sep(prefix[i]))
997 i++;
998 continue;
1000 i++;
1002 if (!is_dir_sep(prefix[prefix_len - 1]))
1003 strbuf_addstr(sb, "../");
1005 strbuf_addstr(sb, in);
1007 return sb->buf;
1011 * A simpler implementation of relative_path
1013 * Get relative path by removing "prefix" from "in". This function
1014 * first appears in v1.5.6-1-g044bbbc, and makes git_dir shorter
1015 * to increase performance when traversing the path to work_tree.
1017 const char *remove_leading_path(const char *in, const char *prefix)
1019 static struct strbuf buf = STRBUF_INIT;
1020 int i = 0, j = 0;
1022 if (!prefix || !prefix[0])
1023 return in;
1024 while (prefix[i]) {
1025 if (is_dir_sep(prefix[i])) {
1026 if (!is_dir_sep(in[j]))
1027 return in;
1028 while (is_dir_sep(prefix[i]))
1029 i++;
1030 while (is_dir_sep(in[j]))
1031 j++;
1032 continue;
1033 } else if (in[j] != prefix[i]) {
1034 return in;
1036 i++;
1037 j++;
1039 if (
1040 /* "/foo" is a prefix of "/foo" */
1041 in[j] &&
1042 /* "/foo" is not a prefix of "/foobar" */
1043 !is_dir_sep(prefix[i-1]) && !is_dir_sep(in[j])
1045 return in;
1046 while (is_dir_sep(in[j]))
1047 j++;
1049 strbuf_reset(&buf);
1050 if (!in[j])
1051 strbuf_addstr(&buf, ".");
1052 else
1053 strbuf_addstr(&buf, in + j);
1054 return buf.buf;
1058 * It is okay if dst == src, but they should not overlap otherwise.
1060 * Performs the following normalizations on src, storing the result in dst:
1061 * - Ensures that components are separated by '/' (Windows only)
1062 * - Squashes sequences of '/' except "//server/share" on Windows
1063 * - Removes "." components.
1064 * - Removes ".." components, and the components the precede them.
1065 * Returns failure (non-zero) if a ".." component appears as first path
1066 * component anytime during the normalization. Otherwise, returns success (0).
1068 * Note that this function is purely textual. It does not follow symlinks,
1069 * verify the existence of the path, or make any system calls.
1071 * prefix_len != NULL is for a specific case of prefix_pathspec():
1072 * assume that src == dst and src[0..prefix_len-1] is already
1073 * normalized, any time "../" eats up to the prefix_len part,
1074 * prefix_len is reduced. In the end prefix_len is the remaining
1075 * prefix that has not been overridden by user pathspec.
1077 * NEEDSWORK: This function doesn't perform normalization w.r.t. trailing '/'.
1078 * For everything but the root folder itself, the normalized path should not
1079 * end with a '/', then the callers need to be fixed up accordingly.
1082 int normalize_path_copy_len(char *dst, const char *src, int *prefix_len)
1084 char *dst0;
1085 const char *end;
1088 * Copy initial part of absolute path: "/", "C:/", "//server/share/".
1090 end = src + offset_1st_component(src);
1091 while (src < end) {
1092 char c = *src++;
1093 if (is_dir_sep(c))
1094 c = '/';
1095 *dst++ = c;
1097 dst0 = dst;
1099 while (is_dir_sep(*src))
1100 src++;
1102 for (;;) {
1103 char c = *src;
1106 * A path component that begins with . could be
1107 * special:
1108 * (1) "." and ends -- ignore and terminate.
1109 * (2) "./" -- ignore them, eat slash and continue.
1110 * (3) ".." and ends -- strip one and terminate.
1111 * (4) "../" -- strip one, eat slash and continue.
1113 if (c == '.') {
1114 if (!src[1]) {
1115 /* (1) */
1116 src++;
1117 } else if (is_dir_sep(src[1])) {
1118 /* (2) */
1119 src += 2;
1120 while (is_dir_sep(*src))
1121 src++;
1122 continue;
1123 } else if (src[1] == '.') {
1124 if (!src[2]) {
1125 /* (3) */
1126 src += 2;
1127 goto up_one;
1128 } else if (is_dir_sep(src[2])) {
1129 /* (4) */
1130 src += 3;
1131 while (is_dir_sep(*src))
1132 src++;
1133 goto up_one;
1138 /* copy up to the next '/', and eat all '/' */
1139 while ((c = *src++) != '\0' && !is_dir_sep(c))
1140 *dst++ = c;
1141 if (is_dir_sep(c)) {
1142 *dst++ = '/';
1143 while (is_dir_sep(c))
1144 c = *src++;
1145 src--;
1146 } else if (!c)
1147 break;
1148 continue;
1150 up_one:
1152 * dst0..dst is prefix portion, and dst[-1] is '/';
1153 * go up one level.
1155 dst--; /* go to trailing '/' */
1156 if (dst <= dst0)
1157 return -1;
1158 /* Windows: dst[-1] cannot be backslash anymore */
1159 while (dst0 < dst && dst[-1] != '/')
1160 dst--;
1161 if (prefix_len && *prefix_len > dst - dst0)
1162 *prefix_len = dst - dst0;
1164 *dst = '\0';
1165 return 0;
1168 int normalize_path_copy(char *dst, const char *src)
1170 return normalize_path_copy_len(dst, src, NULL);
1174 * path = Canonical absolute path
1175 * prefixes = string_list containing normalized, absolute paths without
1176 * trailing slashes (except for the root directory, which is denoted by "/").
1178 * Determines, for each path in prefixes, whether the "prefix"
1179 * is an ancestor directory of path. Returns the length of the longest
1180 * ancestor directory, excluding any trailing slashes, or -1 if no prefix
1181 * is an ancestor. (Note that this means 0 is returned if prefixes is
1182 * ["/"].) "/foo" is not considered an ancestor of "/foobar". Directories
1183 * are not considered to be their own ancestors. path must be in a
1184 * canonical form: empty components, or "." or ".." components are not
1185 * allowed.
1187 int longest_ancestor_length(const char *path, struct string_list *prefixes)
1189 int i, max_len = -1;
1191 if (!strcmp(path, "/"))
1192 return -1;
1194 for (i = 0; i < prefixes->nr; i++) {
1195 const char *ceil = prefixes->items[i].string;
1196 int len = strlen(ceil);
1198 if (len == 1 && ceil[0] == '/')
1199 len = 0; /* root matches anything, with length 0 */
1200 else if (!strncmp(path, ceil, len) && path[len] == '/')
1201 ; /* match of length len */
1202 else
1203 continue; /* no match */
1205 if (len > max_len)
1206 max_len = len;
1209 return max_len;
1212 /* strip arbitrary amount of directory separators at end of path */
1213 static inline int chomp_trailing_dir_sep(const char *path, int len)
1215 while (len && is_dir_sep(path[len - 1]))
1216 len--;
1217 return len;
1221 * If path ends with suffix (complete path components), returns the
1222 * part before suffix (sans trailing directory separators).
1223 * Otherwise returns NULL.
1225 char *strip_path_suffix(const char *path, const char *suffix)
1227 int path_len = strlen(path), suffix_len = strlen(suffix);
1229 while (suffix_len) {
1230 if (!path_len)
1231 return NULL;
1233 if (is_dir_sep(path[path_len - 1])) {
1234 if (!is_dir_sep(suffix[suffix_len - 1]))
1235 return NULL;
1236 path_len = chomp_trailing_dir_sep(path, path_len);
1237 suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
1239 else if (path[--path_len] != suffix[--suffix_len])
1240 return NULL;
1243 if (path_len && !is_dir_sep(path[path_len - 1]))
1244 return NULL;
1245 return xstrndup(path, chomp_trailing_dir_sep(path, path_len));
1248 int daemon_avoid_alias(const char *p)
1250 int sl, ndot;
1253 * This resurrects the belts and suspenders paranoia check by HPA
1254 * done in <435560F7.4080006@zytor.com> thread, now enter_repo()
1255 * does not do getcwd() based path canonicalization.
1257 * sl becomes true immediately after seeing '/' and continues to
1258 * be true as long as dots continue after that without intervening
1259 * non-dot character.
1261 if (!p || (*p != '/' && *p != '~'))
1262 return -1;
1263 sl = 1; ndot = 0;
1264 p++;
1266 while (1) {
1267 char ch = *p++;
1268 if (sl) {
1269 if (ch == '.')
1270 ndot++;
1271 else if (ch == '/') {
1272 if (ndot < 3)
1273 /* reject //, /./ and /../ */
1274 return -1;
1275 ndot = 0;
1277 else if (ch == 0) {
1278 if (0 < ndot && ndot < 3)
1279 /* reject /.$ and /..$ */
1280 return -1;
1281 return 0;
1283 else
1284 sl = ndot = 0;
1286 else if (ch == 0)
1287 return 0;
1288 else if (ch == '/') {
1289 sl = 1;
1290 ndot = 0;
1295 static int only_spaces_and_periods(const char *path, size_t len, size_t skip)
1297 if (len < skip)
1298 return 0;
1299 len -= skip;
1300 path += skip;
1301 while (len-- > 0) {
1302 char c = *(path++);
1303 if (c != ' ' && c != '.')
1304 return 0;
1306 return 1;
1309 int is_ntfs_dotgit(const char *name)
1311 size_t len;
1313 for (len = 0; ; len++)
1314 if (!name[len] || name[len] == '\\' || is_dir_sep(name[len])) {
1315 if (only_spaces_and_periods(name, len, 4) &&
1316 !strncasecmp(name, ".git", 4))
1317 return 1;
1318 if (only_spaces_and_periods(name, len, 5) &&
1319 !strncasecmp(name, "git~1", 5))
1320 return 1;
1321 if (name[len] != '\\')
1322 return 0;
1323 name += len + 1;
1324 len = -1;
1328 static int is_ntfs_dot_generic(const char *name,
1329 const char *dotgit_name,
1330 size_t len,
1331 const char *dotgit_ntfs_shortname_prefix)
1333 int saw_tilde;
1334 size_t i;
1336 if ((name[0] == '.' && !strncasecmp(name + 1, dotgit_name, len))) {
1337 i = len + 1;
1338 only_spaces_and_periods:
1339 for (;;) {
1340 char c = name[i++];
1341 if (!c)
1342 return 1;
1343 if (c != ' ' && c != '.')
1344 return 0;
1349 * Is it a regular NTFS short name, i.e. shortened to 6 characters,
1350 * followed by ~1, ... ~4?
1352 if (!strncasecmp(name, dotgit_name, 6) && name[6] == '~' &&
1353 name[7] >= '1' && name[7] <= '4') {
1354 i = 8;
1355 goto only_spaces_and_periods;
1359 * Is it a fall-back NTFS short name (for details, see
1360 * https://en.wikipedia.org/wiki/8.3_filename?
1362 for (i = 0, saw_tilde = 0; i < 8; i++)
1363 if (name[i] == '\0')
1364 return 0;
1365 else if (saw_tilde) {
1366 if (name[i] < '0' || name[i] > '9')
1367 return 0;
1368 } else if (name[i] == '~') {
1369 if (name[++i] < '1' || name[i] > '9')
1370 return 0;
1371 saw_tilde = 1;
1372 } else if (i >= 6)
1373 return 0;
1374 else if (name[i] & 0x80) {
1376 * We know our needles contain only ASCII, so we clamp
1377 * here to make the results of tolower() sane.
1379 return 0;
1380 } else if (tolower(name[i]) != dotgit_ntfs_shortname_prefix[i])
1381 return 0;
1383 goto only_spaces_and_periods;
1387 * Inline helper to make sure compiler resolves strlen() on literals at
1388 * compile time.
1390 static inline int is_ntfs_dot_str(const char *name, const char *dotgit_name,
1391 const char *dotgit_ntfs_shortname_prefix)
1393 return is_ntfs_dot_generic(name, dotgit_name, strlen(dotgit_name),
1394 dotgit_ntfs_shortname_prefix);
1397 int is_ntfs_dotgitmodules(const char *name)
1399 return is_ntfs_dot_str(name, "gitmodules", "gi7eba");
1402 int is_ntfs_dotgitignore(const char *name)
1404 return is_ntfs_dot_str(name, "gitignore", "gi250a");
1407 int is_ntfs_dotgitattributes(const char *name)
1409 return is_ntfs_dot_str(name, "gitattributes", "gi7d29");
1412 int looks_like_command_line_option(const char *str)
1414 return str && str[0] == '-';
1417 char *xdg_config_home(const char *filename)
1419 const char *home, *config_home;
1421 assert(filename);
1422 config_home = getenv("XDG_CONFIG_HOME");
1423 if (config_home && *config_home)
1424 return mkpathdup("%s/git/%s", config_home, filename);
1426 home = getenv("HOME");
1427 if (home)
1428 return mkpathdup("%s/.config/git/%s", home, filename);
1429 return NULL;
1432 char *xdg_cache_home(const char *filename)
1434 const char *home, *cache_home;
1436 assert(filename);
1437 cache_home = getenv("XDG_CACHE_HOME");
1438 if (cache_home && *cache_home)
1439 return mkpathdup("%s/git/%s", cache_home, filename);
1441 home = getenv("HOME");
1442 if (home)
1443 return mkpathdup("%s/.cache/git/%s", home, filename);
1444 return NULL;
1447 REPO_GIT_PATH_FUNC(cherry_pick_head, "CHERRY_PICK_HEAD")
1448 REPO_GIT_PATH_FUNC(revert_head, "REVERT_HEAD")
1449 REPO_GIT_PATH_FUNC(squash_msg, "SQUASH_MSG")
1450 REPO_GIT_PATH_FUNC(merge_msg, "MERGE_MSG")
1451 REPO_GIT_PATH_FUNC(merge_rr, "MERGE_RR")
1452 REPO_GIT_PATH_FUNC(merge_mode, "MERGE_MODE")
1453 REPO_GIT_PATH_FUNC(merge_head, "MERGE_HEAD")
1454 REPO_GIT_PATH_FUNC(fetch_head, "FETCH_HEAD")
1455 REPO_GIT_PATH_FUNC(shallow, "shallow")