Merge branch 'lt/gpg-show-long-key-in-signature-verification'
[alt-git.git] / path.c
blobfe3c4d96c6d82b2c8f4e1553f1a52e410c8c02d3
1 /*
2 * Utilities for paths and pathnames
3 */
4 #include "cache.h"
5 #include "strbuf.h"
6 #include "string-list.h"
7 #include "dir.h"
8 #include "worktree.h"
10 static int get_st_mode_bits(const char *path, int *mode)
12 struct stat st;
13 if (lstat(path, &st) < 0)
14 return -1;
15 *mode = st.st_mode;
16 return 0;
19 static char bad_path[] = "/bad-path/";
21 static struct strbuf *get_pathname(void)
23 static struct strbuf pathname_array[4] = {
24 STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
26 static int index;
27 struct strbuf *sb = &pathname_array[3 & ++index];
28 strbuf_reset(sb);
29 return sb;
32 static char *cleanup_path(char *path)
34 /* Clean it up */
35 if (!memcmp(path, "./", 2)) {
36 path += 2;
37 while (*path == '/')
38 path++;
40 return path;
43 static void strbuf_cleanup_path(struct strbuf *sb)
45 char *path = cleanup_path(sb->buf);
46 if (path > sb->buf)
47 strbuf_remove(sb, 0, path - sb->buf);
50 char *mksnpath(char *buf, size_t n, const char *fmt, ...)
52 va_list args;
53 unsigned len;
55 va_start(args, fmt);
56 len = vsnprintf(buf, n, fmt, args);
57 va_end(args);
58 if (len >= n) {
59 strlcpy(buf, bad_path, n);
60 return buf;
62 return cleanup_path(buf);
65 static int dir_prefix(const char *buf, const char *dir)
67 int len = strlen(dir);
68 return !strncmp(buf, dir, len) &&
69 (is_dir_sep(buf[len]) || buf[len] == '\0');
72 /* $buf =~ m|$dir/+$file| but without regex */
73 static int is_dir_file(const char *buf, const char *dir, const char *file)
75 int len = strlen(dir);
76 if (strncmp(buf, dir, len) || !is_dir_sep(buf[len]))
77 return 0;
78 while (is_dir_sep(buf[len]))
79 len++;
80 return !strcmp(buf + len, file);
83 static void replace_dir(struct strbuf *buf, int len, const char *newdir)
85 int newlen = strlen(newdir);
86 int need_sep = (buf->buf[len] && !is_dir_sep(buf->buf[len])) &&
87 !is_dir_sep(newdir[newlen - 1]);
88 if (need_sep)
89 len--; /* keep one char, to be replaced with '/' */
90 strbuf_splice(buf, 0, len, newdir, newlen);
91 if (need_sep)
92 buf->buf[newlen] = '/';
95 struct common_dir {
96 /* Not considered garbage for report_linked_checkout_garbage */
97 unsigned ignore_garbage:1;
98 unsigned is_dir:1;
99 /* Not common even though its parent is */
100 unsigned exclude:1;
101 const char *dirname;
104 static struct common_dir common_list[] = {
105 { 0, 1, 0, "branches" },
106 { 0, 1, 0, "hooks" },
107 { 0, 1, 0, "info" },
108 { 0, 0, 1, "info/sparse-checkout" },
109 { 1, 1, 0, "logs" },
110 { 1, 1, 1, "logs/HEAD" },
111 { 0, 1, 1, "logs/refs/bisect" },
112 { 0, 1, 0, "lost-found" },
113 { 0, 1, 0, "objects" },
114 { 0, 1, 0, "refs" },
115 { 0, 1, 1, "refs/bisect" },
116 { 0, 1, 0, "remotes" },
117 { 0, 1, 0, "worktrees" },
118 { 0, 1, 0, "rr-cache" },
119 { 0, 1, 0, "svn" },
120 { 0, 0, 0, "config" },
121 { 1, 0, 0, "gc.pid" },
122 { 0, 0, 0, "packed-refs" },
123 { 0, 0, 0, "shallow" },
124 { 0, 0, 0, NULL }
128 * A compressed trie. A trie node consists of zero or more characters that
129 * are common to all elements with this prefix, optionally followed by some
130 * children. If value is not NULL, the trie node is a terminal node.
132 * For example, consider the following set of strings:
133 * abc
134 * def
135 * definite
136 * definition
138 * The trie would look like:
139 * root: len = 0, children a and d non-NULL, value = NULL.
140 * a: len = 2, contents = bc, value = (data for "abc")
141 * d: len = 2, contents = ef, children i non-NULL, value = (data for "def")
142 * i: len = 3, contents = nit, children e and i non-NULL, value = NULL
143 * e: len = 0, children all NULL, value = (data for "definite")
144 * i: len = 2, contents = on, children all NULL,
145 * value = (data for "definition")
147 struct trie {
148 struct trie *children[256];
149 int len;
150 char *contents;
151 void *value;
154 static struct trie *make_trie_node(const char *key, void *value)
156 struct trie *new_node = xcalloc(1, sizeof(*new_node));
157 new_node->len = strlen(key);
158 if (new_node->len) {
159 new_node->contents = xmalloc(new_node->len);
160 memcpy(new_node->contents, key, new_node->len);
162 new_node->value = value;
163 return new_node;
167 * Add a key/value pair to a trie. The key is assumed to be \0-terminated.
168 * If there was an existing value for this key, return it.
170 static void *add_to_trie(struct trie *root, const char *key, void *value)
172 struct trie *child;
173 void *old;
174 int i;
176 if (!*key) {
177 /* we have reached the end of the key */
178 old = root->value;
179 root->value = value;
180 return old;
183 for (i = 0; i < root->len; i++) {
184 if (root->contents[i] == key[i])
185 continue;
188 * Split this node: child will contain this node's
189 * existing children.
191 child = malloc(sizeof(*child));
192 memcpy(child->children, root->children, sizeof(root->children));
194 child->len = root->len - i - 1;
195 if (child->len) {
196 child->contents = xstrndup(root->contents + i + 1,
197 child->len);
199 child->value = root->value;
200 root->value = NULL;
201 root->len = i;
203 memset(root->children, 0, sizeof(root->children));
204 root->children[(unsigned char)root->contents[i]] = child;
206 /* This is the newly-added child. */
207 root->children[(unsigned char)key[i]] =
208 make_trie_node(key + i + 1, value);
209 return NULL;
212 /* We have matched the entire compressed section */
213 if (key[i]) {
214 child = root->children[(unsigned char)key[root->len]];
215 if (child) {
216 return add_to_trie(child, key + root->len + 1, value);
217 } else {
218 child = make_trie_node(key + root->len + 1, value);
219 root->children[(unsigned char)key[root->len]] = child;
220 return NULL;
224 old = root->value;
225 root->value = value;
226 return old;
229 typedef int (*match_fn)(const char *unmatched, void *data, void *baton);
232 * Search a trie for some key. Find the longest /-or-\0-terminated
233 * prefix of the key for which the trie contains a value. Call fn
234 * with the unmatched portion of the key and the found value, and
235 * return its return value. If there is no such prefix, return -1.
237 * The key is partially normalized: consecutive slashes are skipped.
239 * For example, consider the trie containing only [refs,
240 * refs/worktree] (both with values).
242 * | key | unmatched | val from node | return value |
243 * |-----------------|------------|---------------|--------------|
244 * | a | not called | n/a | -1 |
245 * | refs | \0 | refs | as per fn |
246 * | refs/ | / | refs | as per fn |
247 * | refs/w | /w | refs | as per fn |
248 * | refs/worktree | \0 | refs/worktree | as per fn |
249 * | refs/worktree/ | / | refs/worktree | as per fn |
250 * | refs/worktree/a | /a | refs/worktree | as per fn |
251 * |-----------------|------------|---------------|--------------|
254 static int trie_find(struct trie *root, const char *key, match_fn fn,
255 void *baton)
257 int i;
258 int result;
259 struct trie *child;
261 if (!*key) {
262 /* we have reached the end of the key */
263 if (root->value && !root->len)
264 return fn(key, root->value, baton);
265 else
266 return -1;
269 for (i = 0; i < root->len; i++) {
270 /* Partial path normalization: skip consecutive slashes. */
271 if (key[i] == '/' && key[i+1] == '/') {
272 key++;
273 continue;
275 if (root->contents[i] != key[i])
276 return -1;
279 /* Matched the entire compressed section */
280 key += i;
281 if (!*key)
282 /* End of key */
283 return fn(key, root->value, baton);
285 /* Partial path normalization: skip consecutive slashes */
286 while (key[0] == '/' && key[1] == '/')
287 key++;
289 child = root->children[(unsigned char)*key];
290 if (child)
291 result = trie_find(child, key + 1, fn, baton);
292 else
293 result = -1;
295 if (result >= 0 || (*key != '/' && *key != 0))
296 return result;
297 if (root->value)
298 return fn(key, root->value, baton);
299 else
300 return -1;
303 static struct trie common_trie;
304 static int common_trie_done_setup;
306 static void init_common_trie(void)
308 struct common_dir *p;
310 if (common_trie_done_setup)
311 return;
313 for (p = common_list; p->dirname; p++)
314 add_to_trie(&common_trie, p->dirname, p);
316 common_trie_done_setup = 1;
320 * Helper function for update_common_dir: returns 1 if the dir
321 * prefix is common.
323 static int check_common(const char *unmatched, void *value, void *baton)
325 struct common_dir *dir = value;
327 if (!dir)
328 return 0;
330 if (dir->is_dir && (unmatched[0] == 0 || unmatched[0] == '/'))
331 return !dir->exclude;
333 if (!dir->is_dir && unmatched[0] == 0)
334 return !dir->exclude;
336 return 0;
339 static void update_common_dir(struct strbuf *buf, int git_dir_len,
340 const char *common_dir)
342 char *base = buf->buf + git_dir_len;
343 init_common_trie();
344 if (!common_dir)
345 common_dir = get_git_common_dir();
346 if (trie_find(&common_trie, base, check_common, NULL) > 0)
347 replace_dir(buf, git_dir_len, common_dir);
350 void report_linked_checkout_garbage(void)
352 struct strbuf sb = STRBUF_INIT;
353 const struct common_dir *p;
354 int len;
356 if (!git_common_dir_env)
357 return;
358 strbuf_addf(&sb, "%s/", get_git_dir());
359 len = sb.len;
360 for (p = common_list; p->dirname; p++) {
361 const char *path = p->dirname;
362 if (p->ignore_garbage)
363 continue;
364 strbuf_setlen(&sb, len);
365 strbuf_addstr(&sb, path);
366 if (file_exists(sb.buf))
367 report_garbage(PACKDIR_FILE_GARBAGE, sb.buf);
369 strbuf_release(&sb);
372 static void adjust_git_path(struct strbuf *buf, int git_dir_len)
374 const char *base = buf->buf + git_dir_len;
375 if (git_graft_env && is_dir_file(base, "info", "grafts"))
376 strbuf_splice(buf, 0, buf->len,
377 get_graft_file(), strlen(get_graft_file()));
378 else if (git_index_env && !strcmp(base, "index"))
379 strbuf_splice(buf, 0, buf->len,
380 get_index_file(), strlen(get_index_file()));
381 else if (git_db_env && dir_prefix(base, "objects"))
382 replace_dir(buf, git_dir_len + 7, get_object_directory());
383 else if (git_hooks_path && dir_prefix(base, "hooks"))
384 replace_dir(buf, git_dir_len + 5, git_hooks_path);
385 else if (git_common_dir_env)
386 update_common_dir(buf, git_dir_len, NULL);
389 static void do_git_path(const struct worktree *wt, struct strbuf *buf,
390 const char *fmt, va_list args)
392 int gitdir_len;
393 strbuf_addstr(buf, get_worktree_git_dir(wt));
394 if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
395 strbuf_addch(buf, '/');
396 gitdir_len = buf->len;
397 strbuf_vaddf(buf, fmt, args);
398 adjust_git_path(buf, gitdir_len);
399 strbuf_cleanup_path(buf);
402 char *git_path_buf(struct strbuf *buf, const char *fmt, ...)
404 va_list args;
405 strbuf_reset(buf);
406 va_start(args, fmt);
407 do_git_path(NULL, buf, fmt, args);
408 va_end(args);
409 return buf->buf;
412 void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
414 va_list args;
415 va_start(args, fmt);
416 do_git_path(NULL, sb, fmt, args);
417 va_end(args);
420 const char *git_path(const char *fmt, ...)
422 struct strbuf *pathname = get_pathname();
423 va_list args;
424 va_start(args, fmt);
425 do_git_path(NULL, pathname, fmt, args);
426 va_end(args);
427 return pathname->buf;
430 char *git_pathdup(const char *fmt, ...)
432 struct strbuf path = STRBUF_INIT;
433 va_list args;
434 va_start(args, fmt);
435 do_git_path(NULL, &path, fmt, args);
436 va_end(args);
437 return strbuf_detach(&path, NULL);
440 char *mkpathdup(const char *fmt, ...)
442 struct strbuf sb = STRBUF_INIT;
443 va_list args;
444 va_start(args, fmt);
445 strbuf_vaddf(&sb, fmt, args);
446 va_end(args);
447 strbuf_cleanup_path(&sb);
448 return strbuf_detach(&sb, NULL);
451 const char *mkpath(const char *fmt, ...)
453 va_list args;
454 struct strbuf *pathname = get_pathname();
455 va_start(args, fmt);
456 strbuf_vaddf(pathname, fmt, args);
457 va_end(args);
458 return cleanup_path(pathname->buf);
461 const char *worktree_git_path(const struct worktree *wt, const char *fmt, ...)
463 struct strbuf *pathname = get_pathname();
464 va_list args;
465 va_start(args, fmt);
466 do_git_path(wt, pathname, fmt, args);
467 va_end(args);
468 return pathname->buf;
471 static void do_submodule_path(struct strbuf *buf, const char *path,
472 const char *fmt, va_list args)
474 const char *git_dir;
475 struct strbuf git_submodule_common_dir = STRBUF_INIT;
476 struct strbuf git_submodule_dir = STRBUF_INIT;
478 strbuf_addstr(buf, path);
479 strbuf_complete(buf, '/');
480 strbuf_addstr(buf, ".git");
482 git_dir = read_gitfile(buf->buf);
483 if (git_dir) {
484 strbuf_reset(buf);
485 strbuf_addstr(buf, git_dir);
487 strbuf_addch(buf, '/');
488 strbuf_addbuf(&git_submodule_dir, buf);
490 strbuf_vaddf(buf, fmt, args);
492 if (get_common_dir_noenv(&git_submodule_common_dir, git_submodule_dir.buf))
493 update_common_dir(buf, git_submodule_dir.len, git_submodule_common_dir.buf);
495 strbuf_cleanup_path(buf);
497 strbuf_release(&git_submodule_dir);
498 strbuf_release(&git_submodule_common_dir);
501 char *git_pathdup_submodule(const char *path, const char *fmt, ...)
503 va_list args;
504 struct strbuf buf = STRBUF_INIT;
505 va_start(args, fmt);
506 do_submodule_path(&buf, path, fmt, args);
507 va_end(args);
508 return strbuf_detach(&buf, NULL);
511 void strbuf_git_path_submodule(struct strbuf *buf, const char *path,
512 const char *fmt, ...)
514 va_list args;
515 va_start(args, fmt);
516 do_submodule_path(buf, path, fmt, args);
517 va_end(args);
520 static void do_git_common_path(struct strbuf *buf,
521 const char *fmt,
522 va_list args)
524 strbuf_addstr(buf, get_git_common_dir());
525 if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
526 strbuf_addch(buf, '/');
527 strbuf_vaddf(buf, fmt, args);
528 strbuf_cleanup_path(buf);
531 const char *git_common_path(const char *fmt, ...)
533 struct strbuf *pathname = get_pathname();
534 va_list args;
535 va_start(args, fmt);
536 do_git_common_path(pathname, fmt, args);
537 va_end(args);
538 return pathname->buf;
541 void strbuf_git_common_path(struct strbuf *sb, const char *fmt, ...)
543 va_list args;
544 va_start(args, fmt);
545 do_git_common_path(sb, fmt, args);
546 va_end(args);
549 int validate_headref(const char *path)
551 struct stat st;
552 char *buf, buffer[256];
553 unsigned char sha1[20];
554 int fd;
555 ssize_t len;
557 if (lstat(path, &st) < 0)
558 return -1;
560 /* Make sure it is a "refs/.." symlink */
561 if (S_ISLNK(st.st_mode)) {
562 len = readlink(path, buffer, sizeof(buffer)-1);
563 if (len >= 5 && !memcmp("refs/", buffer, 5))
564 return 0;
565 return -1;
569 * Anything else, just open it and try to see if it is a symbolic ref.
571 fd = open(path, O_RDONLY);
572 if (fd < 0)
573 return -1;
574 len = read_in_full(fd, buffer, sizeof(buffer)-1);
575 close(fd);
578 * Is it a symbolic ref?
580 if (len < 4)
581 return -1;
582 if (!memcmp("ref:", buffer, 4)) {
583 buf = buffer + 4;
584 len -= 4;
585 while (len && isspace(*buf))
586 buf++, len--;
587 if (len >= 5 && !memcmp("refs/", buf, 5))
588 return 0;
592 * Is this a detached HEAD?
594 if (!get_sha1_hex(buffer, sha1))
595 return 0;
597 return -1;
600 static struct passwd *getpw_str(const char *username, size_t len)
602 struct passwd *pw;
603 char *username_z = xmemdupz(username, len);
604 pw = getpwnam(username_z);
605 free(username_z);
606 return pw;
610 * Return a string with ~ and ~user expanded via getpw*. If buf != NULL,
611 * then it is a newly allocated string. Returns NULL on getpw failure or
612 * if path is NULL.
614 char *expand_user_path(const char *path)
616 struct strbuf user_path = STRBUF_INIT;
617 const char *to_copy = path;
619 if (path == NULL)
620 goto return_null;
621 if (path[0] == '~') {
622 const char *first_slash = strchrnul(path, '/');
623 const char *username = path + 1;
624 size_t username_len = first_slash - username;
625 if (username_len == 0) {
626 const char *home = getenv("HOME");
627 if (!home)
628 goto return_null;
629 strbuf_addstr(&user_path, home);
630 #ifdef GIT_WINDOWS_NATIVE
631 convert_slashes(user_path.buf);
632 #endif
633 } else {
634 struct passwd *pw = getpw_str(username, username_len);
635 if (!pw)
636 goto return_null;
637 strbuf_addstr(&user_path, pw->pw_dir);
639 to_copy = first_slash;
641 strbuf_addstr(&user_path, to_copy);
642 return strbuf_detach(&user_path, NULL);
643 return_null:
644 strbuf_release(&user_path);
645 return NULL;
649 * First, one directory to try is determined by the following algorithm.
651 * (0) If "strict" is given, the path is used as given and no DWIM is
652 * done. Otherwise:
653 * (1) "~/path" to mean path under the running user's home directory;
654 * (2) "~user/path" to mean path under named user's home directory;
655 * (3) "relative/path" to mean cwd relative directory; or
656 * (4) "/absolute/path" to mean absolute directory.
658 * Unless "strict" is given, we check "%s/.git", "%s", "%s.git/.git", "%s.git"
659 * in this order. We select the first one that is a valid git repository, and
660 * chdir() to it. If none match, or we fail to chdir, we return NULL.
662 * If all goes well, we return the directory we used to chdir() (but
663 * before ~user is expanded), avoiding getcwd() resolving symbolic
664 * links. User relative paths are also returned as they are given,
665 * except DWIM suffixing.
667 const char *enter_repo(const char *path, int strict)
669 static struct strbuf validated_path = STRBUF_INIT;
670 static struct strbuf used_path = STRBUF_INIT;
672 if (!path)
673 return NULL;
675 if (!strict) {
676 static const char *suffix[] = {
677 "/.git", "", ".git/.git", ".git", NULL,
679 const char *gitfile;
680 int len = strlen(path);
681 int i;
682 while ((1 < len) && (path[len-1] == '/'))
683 len--;
686 * We can handle arbitrary-sized buffers, but this remains as a
687 * sanity check on untrusted input.
689 if (PATH_MAX <= len)
690 return NULL;
692 strbuf_reset(&used_path);
693 strbuf_reset(&validated_path);
694 strbuf_add(&used_path, path, len);
695 strbuf_add(&validated_path, path, len);
697 if (used_path.buf[0] == '~') {
698 char *newpath = expand_user_path(used_path.buf);
699 if (!newpath)
700 return NULL;
701 strbuf_attach(&used_path, newpath, strlen(newpath),
702 strlen(newpath));
704 for (i = 0; suffix[i]; i++) {
705 struct stat st;
706 size_t baselen = used_path.len;
707 strbuf_addstr(&used_path, suffix[i]);
708 if (!stat(used_path.buf, &st) &&
709 (S_ISREG(st.st_mode) ||
710 (S_ISDIR(st.st_mode) && is_git_directory(used_path.buf)))) {
711 strbuf_addstr(&validated_path, suffix[i]);
712 break;
714 strbuf_setlen(&used_path, baselen);
716 if (!suffix[i])
717 return NULL;
718 gitfile = read_gitfile(used_path.buf);
719 if (gitfile) {
720 strbuf_reset(&used_path);
721 strbuf_addstr(&used_path, gitfile);
723 if (chdir(used_path.buf))
724 return NULL;
725 path = validated_path.buf;
727 else {
728 const char *gitfile = read_gitfile(path);
729 if (gitfile)
730 path = gitfile;
731 if (chdir(path))
732 return NULL;
735 if (is_git_directory(".")) {
736 set_git_dir(".");
737 check_repository_format();
738 return path;
741 return NULL;
744 static int calc_shared_perm(int mode)
746 int tweak;
748 if (get_shared_repository() < 0)
749 tweak = -get_shared_repository();
750 else
751 tweak = get_shared_repository();
753 if (!(mode & S_IWUSR))
754 tweak &= ~0222;
755 if (mode & S_IXUSR)
756 /* Copy read bits to execute bits */
757 tweak |= (tweak & 0444) >> 2;
758 if (get_shared_repository() < 0)
759 mode = (mode & ~0777) | tweak;
760 else
761 mode |= tweak;
763 return mode;
767 int adjust_shared_perm(const char *path)
769 int old_mode, new_mode;
771 if (!get_shared_repository())
772 return 0;
773 if (get_st_mode_bits(path, &old_mode) < 0)
774 return -1;
776 new_mode = calc_shared_perm(old_mode);
777 if (S_ISDIR(old_mode)) {
778 /* Copy read bits to execute bits */
779 new_mode |= (new_mode & 0444) >> 2;
780 new_mode |= FORCE_DIR_SET_GID;
783 if (((old_mode ^ new_mode) & ~S_IFMT) &&
784 chmod(path, (new_mode & ~S_IFMT)) < 0)
785 return -2;
786 return 0;
789 void safe_create_dir(const char *dir, int share)
791 if (mkdir(dir, 0777) < 0) {
792 if (errno != EEXIST) {
793 perror(dir);
794 exit(1);
797 else if (share && adjust_shared_perm(dir))
798 die(_("Could not make %s writable by group"), dir);
801 static int have_same_root(const char *path1, const char *path2)
803 int is_abs1, is_abs2;
805 is_abs1 = is_absolute_path(path1);
806 is_abs2 = is_absolute_path(path2);
807 return (is_abs1 && is_abs2 && tolower(path1[0]) == tolower(path2[0])) ||
808 (!is_abs1 && !is_abs2);
812 * Give path as relative to prefix.
814 * The strbuf may or may not be used, so do not assume it contains the
815 * returned path.
817 const char *relative_path(const char *in, const char *prefix,
818 struct strbuf *sb)
820 int in_len = in ? strlen(in) : 0;
821 int prefix_len = prefix ? strlen(prefix) : 0;
822 int in_off = 0;
823 int prefix_off = 0;
824 int i = 0, j = 0;
826 if (!in_len)
827 return "./";
828 else if (!prefix_len)
829 return in;
831 if (have_same_root(in, prefix))
832 /* bypass dos_drive, for "c:" is identical to "C:" */
833 i = j = has_dos_drive_prefix(in);
834 else {
835 return in;
838 while (i < prefix_len && j < in_len && prefix[i] == in[j]) {
839 if (is_dir_sep(prefix[i])) {
840 while (is_dir_sep(prefix[i]))
841 i++;
842 while (is_dir_sep(in[j]))
843 j++;
844 prefix_off = i;
845 in_off = j;
846 } else {
847 i++;
848 j++;
852 if (
853 /* "prefix" seems like prefix of "in" */
854 i >= prefix_len &&
856 * but "/foo" is not a prefix of "/foobar"
857 * (i.e. prefix not end with '/')
859 prefix_off < prefix_len) {
860 if (j >= in_len) {
861 /* in="/a/b", prefix="/a/b" */
862 in_off = in_len;
863 } else if (is_dir_sep(in[j])) {
864 /* in="/a/b/c", prefix="/a/b" */
865 while (is_dir_sep(in[j]))
866 j++;
867 in_off = j;
868 } else {
869 /* in="/a/bbb/c", prefix="/a/b" */
870 i = prefix_off;
872 } else if (
873 /* "in" is short than "prefix" */
874 j >= in_len &&
875 /* "in" not end with '/' */
876 in_off < in_len) {
877 if (is_dir_sep(prefix[i])) {
878 /* in="/a/b", prefix="/a/b/c/" */
879 while (is_dir_sep(prefix[i]))
880 i++;
881 in_off = in_len;
884 in += in_off;
885 in_len -= in_off;
887 if (i >= prefix_len) {
888 if (!in_len)
889 return "./";
890 else
891 return in;
894 strbuf_reset(sb);
895 strbuf_grow(sb, in_len);
897 while (i < prefix_len) {
898 if (is_dir_sep(prefix[i])) {
899 strbuf_addstr(sb, "../");
900 while (is_dir_sep(prefix[i]))
901 i++;
902 continue;
904 i++;
906 if (!is_dir_sep(prefix[prefix_len - 1]))
907 strbuf_addstr(sb, "../");
909 strbuf_addstr(sb, in);
911 return sb->buf;
915 * A simpler implementation of relative_path
917 * Get relative path by removing "prefix" from "in". This function
918 * first appears in v1.5.6-1-g044bbbc, and makes git_dir shorter
919 * to increase performance when traversing the path to work_tree.
921 const char *remove_leading_path(const char *in, const char *prefix)
923 static struct strbuf buf = STRBUF_INIT;
924 int i = 0, j = 0;
926 if (!prefix || !prefix[0])
927 return in;
928 while (prefix[i]) {
929 if (is_dir_sep(prefix[i])) {
930 if (!is_dir_sep(in[j]))
931 return in;
932 while (is_dir_sep(prefix[i]))
933 i++;
934 while (is_dir_sep(in[j]))
935 j++;
936 continue;
937 } else if (in[j] != prefix[i]) {
938 return in;
940 i++;
941 j++;
943 if (
944 /* "/foo" is a prefix of "/foo" */
945 in[j] &&
946 /* "/foo" is not a prefix of "/foobar" */
947 !is_dir_sep(prefix[i-1]) && !is_dir_sep(in[j])
949 return in;
950 while (is_dir_sep(in[j]))
951 j++;
953 strbuf_reset(&buf);
954 if (!in[j])
955 strbuf_addstr(&buf, ".");
956 else
957 strbuf_addstr(&buf, in + j);
958 return buf.buf;
962 * It is okay if dst == src, but they should not overlap otherwise.
964 * Performs the following normalizations on src, storing the result in dst:
965 * - Ensures that components are separated by '/' (Windows only)
966 * - Squashes sequences of '/'.
967 * - Removes "." components.
968 * - Removes ".." components, and the components the precede them.
969 * Returns failure (non-zero) if a ".." component appears as first path
970 * component anytime during the normalization. Otherwise, returns success (0).
972 * Note that this function is purely textual. It does not follow symlinks,
973 * verify the existence of the path, or make any system calls.
975 * prefix_len != NULL is for a specific case of prefix_pathspec():
976 * assume that src == dst and src[0..prefix_len-1] is already
977 * normalized, any time "../" eats up to the prefix_len part,
978 * prefix_len is reduced. In the end prefix_len is the remaining
979 * prefix that has not been overridden by user pathspec.
981 * NEEDSWORK: This function doesn't perform normalization w.r.t. trailing '/'.
982 * For everything but the root folder itself, the normalized path should not
983 * end with a '/', then the callers need to be fixed up accordingly.
986 int normalize_path_copy_len(char *dst, const char *src, int *prefix_len)
988 char *dst0;
989 int i;
991 for (i = has_dos_drive_prefix(src); i > 0; i--)
992 *dst++ = *src++;
993 dst0 = dst;
995 if (is_dir_sep(*src)) {
996 *dst++ = '/';
997 while (is_dir_sep(*src))
998 src++;
1001 for (;;) {
1002 char c = *src;
1005 * A path component that begins with . could be
1006 * special:
1007 * (1) "." and ends -- ignore and terminate.
1008 * (2) "./" -- ignore them, eat slash and continue.
1009 * (3) ".." and ends -- strip one and terminate.
1010 * (4) "../" -- strip one, eat slash and continue.
1012 if (c == '.') {
1013 if (!src[1]) {
1014 /* (1) */
1015 src++;
1016 } else if (is_dir_sep(src[1])) {
1017 /* (2) */
1018 src += 2;
1019 while (is_dir_sep(*src))
1020 src++;
1021 continue;
1022 } else if (src[1] == '.') {
1023 if (!src[2]) {
1024 /* (3) */
1025 src += 2;
1026 goto up_one;
1027 } else if (is_dir_sep(src[2])) {
1028 /* (4) */
1029 src += 3;
1030 while (is_dir_sep(*src))
1031 src++;
1032 goto up_one;
1037 /* copy up to the next '/', and eat all '/' */
1038 while ((c = *src++) != '\0' && !is_dir_sep(c))
1039 *dst++ = c;
1040 if (is_dir_sep(c)) {
1041 *dst++ = '/';
1042 while (is_dir_sep(c))
1043 c = *src++;
1044 src--;
1045 } else if (!c)
1046 break;
1047 continue;
1049 up_one:
1051 * dst0..dst is prefix portion, and dst[-1] is '/';
1052 * go up one level.
1054 dst--; /* go to trailing '/' */
1055 if (dst <= dst0)
1056 return -1;
1057 /* Windows: dst[-1] cannot be backslash anymore */
1058 while (dst0 < dst && dst[-1] != '/')
1059 dst--;
1060 if (prefix_len && *prefix_len > dst - dst0)
1061 *prefix_len = dst - dst0;
1063 *dst = '\0';
1064 return 0;
1067 int normalize_path_copy(char *dst, const char *src)
1069 return normalize_path_copy_len(dst, src, NULL);
1073 * path = Canonical absolute path
1074 * prefixes = string_list containing normalized, absolute paths without
1075 * trailing slashes (except for the root directory, which is denoted by "/").
1077 * Determines, for each path in prefixes, whether the "prefix"
1078 * is an ancestor directory of path. Returns the length of the longest
1079 * ancestor directory, excluding any trailing slashes, or -1 if no prefix
1080 * is an ancestor. (Note that this means 0 is returned if prefixes is
1081 * ["/"].) "/foo" is not considered an ancestor of "/foobar". Directories
1082 * are not considered to be their own ancestors. path must be in a
1083 * canonical form: empty components, or "." or ".." components are not
1084 * allowed.
1086 int longest_ancestor_length(const char *path, struct string_list *prefixes)
1088 int i, max_len = -1;
1090 if (!strcmp(path, "/"))
1091 return -1;
1093 for (i = 0; i < prefixes->nr; i++) {
1094 const char *ceil = prefixes->items[i].string;
1095 int len = strlen(ceil);
1097 if (len == 1 && ceil[0] == '/')
1098 len = 0; /* root matches anything, with length 0 */
1099 else if (!strncmp(path, ceil, len) && path[len] == '/')
1100 ; /* match of length len */
1101 else
1102 continue; /* no match */
1104 if (len > max_len)
1105 max_len = len;
1108 return max_len;
1111 /* strip arbitrary amount of directory separators at end of path */
1112 static inline int chomp_trailing_dir_sep(const char *path, int len)
1114 while (len && is_dir_sep(path[len - 1]))
1115 len--;
1116 return len;
1120 * If path ends with suffix (complete path components), returns the
1121 * part before suffix (sans trailing directory separators).
1122 * Otherwise returns NULL.
1124 char *strip_path_suffix(const char *path, const char *suffix)
1126 int path_len = strlen(path), suffix_len = strlen(suffix);
1128 while (suffix_len) {
1129 if (!path_len)
1130 return NULL;
1132 if (is_dir_sep(path[path_len - 1])) {
1133 if (!is_dir_sep(suffix[suffix_len - 1]))
1134 return NULL;
1135 path_len = chomp_trailing_dir_sep(path, path_len);
1136 suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
1138 else if (path[--path_len] != suffix[--suffix_len])
1139 return NULL;
1142 if (path_len && !is_dir_sep(path[path_len - 1]))
1143 return NULL;
1144 return xstrndup(path, chomp_trailing_dir_sep(path, path_len));
1147 int daemon_avoid_alias(const char *p)
1149 int sl, ndot;
1152 * This resurrects the belts and suspenders paranoia check by HPA
1153 * done in <435560F7.4080006@zytor.com> thread, now enter_repo()
1154 * does not do getcwd() based path canonicalization.
1156 * sl becomes true immediately after seeing '/' and continues to
1157 * be true as long as dots continue after that without intervening
1158 * non-dot character.
1160 if (!p || (*p != '/' && *p != '~'))
1161 return -1;
1162 sl = 1; ndot = 0;
1163 p++;
1165 while (1) {
1166 char ch = *p++;
1167 if (sl) {
1168 if (ch == '.')
1169 ndot++;
1170 else if (ch == '/') {
1171 if (ndot < 3)
1172 /* reject //, /./ and /../ */
1173 return -1;
1174 ndot = 0;
1176 else if (ch == 0) {
1177 if (0 < ndot && ndot < 3)
1178 /* reject /.$ and /..$ */
1179 return -1;
1180 return 0;
1182 else
1183 sl = ndot = 0;
1185 else if (ch == 0)
1186 return 0;
1187 else if (ch == '/') {
1188 sl = 1;
1189 ndot = 0;
1194 static int only_spaces_and_periods(const char *path, size_t len, size_t skip)
1196 if (len < skip)
1197 return 0;
1198 len -= skip;
1199 path += skip;
1200 while (len-- > 0) {
1201 char c = *(path++);
1202 if (c != ' ' && c != '.')
1203 return 0;
1205 return 1;
1208 int is_ntfs_dotgit(const char *name)
1210 int len;
1212 for (len = 0; ; len++)
1213 if (!name[len] || name[len] == '\\' || is_dir_sep(name[len])) {
1214 if (only_spaces_and_periods(name, len, 4) &&
1215 !strncasecmp(name, ".git", 4))
1216 return 1;
1217 if (only_spaces_and_periods(name, len, 5) &&
1218 !strncasecmp(name, "git~1", 5))
1219 return 1;
1220 if (name[len] != '\\')
1221 return 0;
1222 name += len + 1;
1223 len = -1;
1227 char *xdg_config_home(const char *filename)
1229 const char *home, *config_home;
1231 assert(filename);
1232 config_home = getenv("XDG_CONFIG_HOME");
1233 if (config_home && *config_home)
1234 return mkpathdup("%s/git/%s", config_home, filename);
1236 home = getenv("HOME");
1237 if (home)
1238 return mkpathdup("%s/.config/git/%s", home, filename);
1239 return NULL;
1242 GIT_PATH_FUNC(git_path_cherry_pick_head, "CHERRY_PICK_HEAD")
1243 GIT_PATH_FUNC(git_path_revert_head, "REVERT_HEAD")
1244 GIT_PATH_FUNC(git_path_squash_msg, "SQUASH_MSG")
1245 GIT_PATH_FUNC(git_path_merge_msg, "MERGE_MSG")
1246 GIT_PATH_FUNC(git_path_merge_rr, "MERGE_RR")
1247 GIT_PATH_FUNC(git_path_merge_mode, "MERGE_MODE")
1248 GIT_PATH_FUNC(git_path_merge_head, "MERGE_HEAD")
1249 GIT_PATH_FUNC(git_path_fetch_head, "FETCH_HEAD")
1250 GIT_PATH_FUNC(git_path_shallow, "shallow")