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
9static int get_st_mode_bits(const char *path, int *mode)
10{
11 struct stat st;
12 if (lstat(path, &st) < 0)
13 return -1;
14 *mode = st.st_mode;
15 return 0;
16}
17
18static char bad_path[] = "/bad-path/";
19
20static struct strbuf *get_pathname(void)
21{
22 static struct strbuf pathname_array[4] = {
23 STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
24 };
25 static int index;
26 struct strbuf *sb = &pathname_array[3 & ++index];
27 strbuf_reset(sb);
28 return sb;
29}
30
31static char *cleanup_path(char *path)
32{
33 /* Clean it up */
34 if (!memcmp(path, "./", 2)) {
35 path += 2;
36 while (*path == '/')
37 path++;
38 }
39 return path;
40}
41
42static void strbuf_cleanup_path(struct strbuf *sb)
43{
44 char *path = cleanup_path(sb->buf);
45 if (path > sb->buf)
46 strbuf_remove(sb, 0, path - sb->buf);
47}
48
49char *mksnpath(char *buf, size_t n, const char *fmt, ...)
50{
51 va_list args;
52 unsigned len;
53
54 va_start(args, fmt);
55 len = vsnprintf(buf, n, fmt, args);
56 va_end(args);
57 if (len >= n) {
58 strlcpy(buf, bad_path, n);
59 return buf;
60 }
61 return cleanup_path(buf);
62}
63
64static int dir_prefix(const char *buf, const char *dir)
65{
66 int len = strlen(dir);
67 return !strncmp(buf, dir, len) &&
68 (is_dir_sep(buf[len]) || buf[len] == '\0');
69}
70
71/* $buf =~ m|$dir/+$file| but without regex */
72static int is_dir_file(const char *buf, const char *dir, const char *file)
73{
74 int len = strlen(dir);
75 if (strncmp(buf, dir, len) || !is_dir_sep(buf[len]))
76 return 0;
77 while (is_dir_sep(buf[len]))
78 len++;
79 return !strcmp(buf + len, file);
80}
81
82static void replace_dir(struct strbuf *buf, int len, const char *newdir)
83{
84 int newlen = strlen(newdir);
85 int need_sep = (buf->buf[len] && !is_dir_sep(buf->buf[len])) &&
86 !is_dir_sep(newdir[newlen - 1]);
87 if (need_sep)
88 len--; /* keep one char, to be replaced with '/' */
89 strbuf_splice(buf, 0, len, newdir, newlen);
90 if (need_sep)
91 buf->buf[newlen] = '/';
92}
93
94static const char *common_list[] = {
95 "/branches", "/hooks", "/info", "!/logs", "/lost-found",
96 "/objects", "/refs", "/remotes", "/worktrees", "/rr-cache", "/svn",
97 "config", "!gc.pid", "packed-refs", "shallow",
98 NULL
99};
100
101static void update_common_dir(struct strbuf *buf, int git_dir_len, const char *common_dir)
102{
103 char *base = buf->buf + git_dir_len;
104 const char **p;
105
106 if (is_dir_file(base, "logs", "HEAD") ||
107 is_dir_file(base, "info", "sparse-checkout"))
108 return; /* keep this in $GIT_DIR */
109 for (p = common_list; *p; p++) {
110 const char *path = *p;
111 int is_dir = 0;
112 if (*path == '!')
113 path++;
114 if (*path == '/') {
115 path++;
116 is_dir = 1;
117 }
118
119 if (!common_dir)
120 common_dir = get_git_common_dir();
121
122 if (is_dir && dir_prefix(base, path)) {
123 replace_dir(buf, git_dir_len, common_dir);
124 return;
125 }
126 if (!is_dir && !strcmp(base, path)) {
127 replace_dir(buf, git_dir_len, common_dir);
128 return;
129 }
130 }
131}
132
133void report_linked_checkout_garbage(void)
134{
135 struct strbuf sb = STRBUF_INIT;
136 const char **p;
137 int len;
138
139 if (!git_common_dir_env)
140 return;
141 strbuf_addf(&sb, "%s/", get_git_dir());
142 len = sb.len;
143 for (p = common_list; *p; p++) {
144 const char *path = *p;
145 if (*path == '!')
146 continue;
147 strbuf_setlen(&sb, len);
148 strbuf_addstr(&sb, path);
149 if (file_exists(sb.buf))
150 report_garbage(PACKDIR_FILE_GARBAGE, sb.buf);
151 }
152 strbuf_release(&sb);
153}
154
155static void adjust_git_path(struct strbuf *buf, int git_dir_len)
156{
157 const char *base = buf->buf + git_dir_len;
158 if (git_graft_env && is_dir_file(base, "info", "grafts"))
159 strbuf_splice(buf, 0, buf->len,
160 get_graft_file(), strlen(get_graft_file()));
161 else if (git_index_env && !strcmp(base, "index"))
162 strbuf_splice(buf, 0, buf->len,
163 get_index_file(), strlen(get_index_file()));
164 else if (git_db_env && dir_prefix(base, "objects"))
165 replace_dir(buf, git_dir_len + 7, get_object_directory());
166 else if (git_common_dir_env)
167 update_common_dir(buf, git_dir_len, NULL);
168}
169
170static void do_git_path(struct strbuf *buf, const char *fmt, va_list args)
171{
172 int gitdir_len;
173 strbuf_addstr(buf, get_git_dir());
174 if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
175 strbuf_addch(buf, '/');
176 gitdir_len = buf->len;
177 strbuf_vaddf(buf, fmt, args);
178 adjust_git_path(buf, gitdir_len);
179 strbuf_cleanup_path(buf);
180}
181
182void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
183{
184 va_list args;
185 va_start(args, fmt);
186 do_git_path(sb, fmt, args);
187 va_end(args);
188}
189
190const char *git_path(const char *fmt, ...)
191{
192 struct strbuf *pathname = get_pathname();
193 va_list args;
194 va_start(args, fmt);
195 do_git_path(pathname, fmt, args);
196 va_end(args);
197 return pathname->buf;
198}
199
200char *git_pathdup(const char *fmt, ...)
201{
202 struct strbuf path = STRBUF_INIT;
203 va_list args;
204 va_start(args, fmt);
205 do_git_path(&path, fmt, args);
206 va_end(args);
207 return strbuf_detach(&path, NULL);
208}
209
210char *mkpathdup(const char *fmt, ...)
211{
212 struct strbuf sb = STRBUF_INIT;
213 va_list args;
214 va_start(args, fmt);
215 strbuf_vaddf(&sb, fmt, args);
216 va_end(args);
217 strbuf_cleanup_path(&sb);
218 return strbuf_detach(&sb, NULL);
219}
220
221const char *mkpath(const char *fmt, ...)
222{
223 va_list args;
224 struct strbuf *pathname = get_pathname();
225 va_start(args, fmt);
226 strbuf_vaddf(pathname, fmt, args);
227 va_end(args);
228 return cleanup_path(pathname->buf);
229}
230
231static void do_submodule_path(struct strbuf *buf, const char *path,
232 const char *fmt, va_list args)
233{
234 const char *git_dir;
235 struct strbuf git_submodule_common_dir = STRBUF_INIT;
236 struct strbuf git_submodule_dir = STRBUF_INIT;
237
238 strbuf_addstr(buf, path);
239 if (buf->len && buf->buf[buf->len - 1] != '/')
240 strbuf_addch(buf, '/');
241 strbuf_addstr(buf, ".git");
242
243 git_dir = read_gitfile(buf->buf);
244 if (git_dir) {
245 strbuf_reset(buf);
246 strbuf_addstr(buf, git_dir);
247 }
248 strbuf_addch(buf, '/');
249 strbuf_addstr(&git_submodule_dir, buf->buf);
250
251 strbuf_vaddf(buf, fmt, args);
252
253 if (get_common_dir_noenv(&git_submodule_common_dir, git_submodule_dir.buf))
254 update_common_dir(buf, git_submodule_dir.len, git_submodule_common_dir.buf);
255
256 strbuf_cleanup_path(buf);
257
258 strbuf_release(&git_submodule_dir);
259 strbuf_release(&git_submodule_common_dir);
260}
261
262char *git_pathdup_submodule(const char *path, const char *fmt, ...)
263{
264 va_list args;
265 struct strbuf buf = STRBUF_INIT;
266 va_start(args, fmt);
267 do_submodule_path(&buf, path, fmt, args);
268 va_end(args);
269 return strbuf_detach(&buf, NULL);
270}
271
272void strbuf_git_path_submodule(struct strbuf *buf, const char *path,
273 const char *fmt, ...)
274{
275 va_list args;
276 va_start(args, fmt);
277 do_submodule_path(buf, path, fmt, args);
278 va_end(args);
279}
280
281int validate_headref(const char *path)
282{
283 struct stat st;
284 char *buf, buffer[256];
285 unsigned char sha1[20];
286 int fd;
287 ssize_t len;
288
289 if (lstat(path, &st) < 0)
290 return -1;
291
292 /* Make sure it is a "refs/.." symlink */
293 if (S_ISLNK(st.st_mode)) {
294 len = readlink(path, buffer, sizeof(buffer)-1);
295 if (len >= 5 && !memcmp("refs/", buffer, 5))
296 return 0;
297 return -1;
298 }
299
300 /*
301 * Anything else, just open it and try to see if it is a symbolic ref.
302 */
303 fd = open(path, O_RDONLY);
304 if (fd < 0)
305 return -1;
306 len = read_in_full(fd, buffer, sizeof(buffer)-1);
307 close(fd);
308
309 /*
310 * Is it a symbolic ref?
311 */
312 if (len < 4)
313 return -1;
314 if (!memcmp("ref:", buffer, 4)) {
315 buf = buffer + 4;
316 len -= 4;
317 while (len && isspace(*buf))
318 buf++, len--;
319 if (len >= 5 && !memcmp("refs/", buf, 5))
320 return 0;
321 }
322
323 /*
324 * Is this a detached HEAD?
325 */
326 if (!get_sha1_hex(buffer, sha1))
327 return 0;
328
329 return -1;
330}
331
332static struct passwd *getpw_str(const char *username, size_t len)
333{
334 struct passwd *pw;
335 char *username_z = xmemdupz(username, len);
336 pw = getpwnam(username_z);
337 free(username_z);
338 return pw;
339}
340
341/*
342 * Return a string with ~ and ~user expanded via getpw*. If buf != NULL,
343 * then it is a newly allocated string. Returns NULL on getpw failure or
344 * if path is NULL.
345 */
346char *expand_user_path(const char *path)
347{
348 struct strbuf user_path = STRBUF_INIT;
349 const char *to_copy = path;
350
351 if (path == NULL)
352 goto return_null;
353 if (path[0] == '~') {
354 const char *first_slash = strchrnul(path, '/');
355 const char *username = path + 1;
356 size_t username_len = first_slash - username;
357 if (username_len == 0) {
358 const char *home = getenv("HOME");
359 if (!home)
360 goto return_null;
361 strbuf_addstr(&user_path, home);
362 } else {
363 struct passwd *pw = getpw_str(username, username_len);
364 if (!pw)
365 goto return_null;
366 strbuf_addstr(&user_path, pw->pw_dir);
367 }
368 to_copy = first_slash;
369 }
370 strbuf_addstr(&user_path, to_copy);
371 return strbuf_detach(&user_path, NULL);
372return_null:
373 strbuf_release(&user_path);
374 return NULL;
375}
376
377/*
378 * First, one directory to try is determined by the following algorithm.
379 *
380 * (0) If "strict" is given, the path is used as given and no DWIM is
381 * done. Otherwise:
382 * (1) "~/path" to mean path under the running user's home directory;
383 * (2) "~user/path" to mean path under named user's home directory;
384 * (3) "relative/path" to mean cwd relative directory; or
385 * (4) "/absolute/path" to mean absolute directory.
386 *
387 * Unless "strict" is given, we check "%s/.git", "%s", "%s.git/.git", "%s.git"
388 * in this order. We select the first one that is a valid git repository, and
389 * chdir() to it. If none match, or we fail to chdir, we return NULL.
390 *
391 * If all goes well, we return the directory we used to chdir() (but
392 * before ~user is expanded), avoiding getcwd() resolving symbolic
393 * links. User relative paths are also returned as they are given,
394 * except DWIM suffixing.
395 */
396const char *enter_repo(const char *path, int strict)
397{
398 static char used_path[PATH_MAX];
399 static char validated_path[PATH_MAX];
400
401 if (!path)
402 return NULL;
403
404 if (!strict) {
405 static const char *suffix[] = {
406 "/.git", "", ".git/.git", ".git", NULL,
407 };
408 const char *gitfile;
409 int len = strlen(path);
410 int i;
411 while ((1 < len) && (path[len-1] == '/'))
412 len--;
413
414 if (PATH_MAX <= len)
415 return NULL;
416 strncpy(used_path, path, len); used_path[len] = 0 ;
417 strcpy(validated_path, used_path);
418
419 if (used_path[0] == '~') {
420 char *newpath = expand_user_path(used_path);
421 if (!newpath || (PATH_MAX - 10 < strlen(newpath))) {
422 free(newpath);
423 return NULL;
424 }
425 /*
426 * Copy back into the static buffer. A pity
427 * since newpath was not bounded, but other
428 * branches of the if are limited by PATH_MAX
429 * anyway.
430 */
431 strcpy(used_path, newpath); free(newpath);
432 }
433 else if (PATH_MAX - 10 < len)
434 return NULL;
435 len = strlen(used_path);
436 for (i = 0; suffix[i]; i++) {
437 struct stat st;
438 strcpy(used_path + len, suffix[i]);
439 if (!stat(used_path, &st) &&
440 (S_ISREG(st.st_mode) ||
441 (S_ISDIR(st.st_mode) && is_git_directory(used_path)))) {
442 strcat(validated_path, suffix[i]);
443 break;
444 }
445 }
446 if (!suffix[i])
447 return NULL;
448 gitfile = read_gitfile(used_path);
449 if (gitfile)
450 strcpy(used_path, gitfile);
451 if (chdir(used_path))
452 return NULL;
453 path = validated_path;
454 }
455 else {
456 const char *gitfile = read_gitfile(path);
457 if (gitfile)
458 path = gitfile;
459 if (chdir(path))
460 return NULL;
461 }
462
463 if (is_git_directory(".")) {
464 set_git_dir(".");
465 check_repository_format();
466 return path;
467 }
468
469 return NULL;
470}
471
472static int calc_shared_perm(int mode)
473{
474 int tweak;
475
476 if (shared_repository < 0)
477 tweak = -shared_repository;
478 else
479 tweak = shared_repository;
480
481 if (!(mode & S_IWUSR))
482 tweak &= ~0222;
483 if (mode & S_IXUSR)
484 /* Copy read bits to execute bits */
485 tweak |= (tweak & 0444) >> 2;
486 if (shared_repository < 0)
487 mode = (mode & ~0777) | tweak;
488 else
489 mode |= tweak;
490
491 return mode;
492}
493
494
495int adjust_shared_perm(const char *path)
496{
497 int old_mode, new_mode;
498
499 if (!shared_repository)
500 return 0;
501 if (get_st_mode_bits(path, &old_mode) < 0)
502 return -1;
503
504 new_mode = calc_shared_perm(old_mode);
505 if (S_ISDIR(old_mode)) {
506 /* Copy read bits to execute bits */
507 new_mode |= (new_mode & 0444) >> 2;
508 new_mode |= FORCE_DIR_SET_GID;
509 }
510
511 if (((old_mode ^ new_mode) & ~S_IFMT) &&
512 chmod(path, (new_mode & ~S_IFMT)) < 0)
513 return -2;
514 return 0;
515}
516
517static int have_same_root(const char *path1, const char *path2)
518{
519 int is_abs1, is_abs2;
520
521 is_abs1 = is_absolute_path(path1);
522 is_abs2 = is_absolute_path(path2);
523 return (is_abs1 && is_abs2 && tolower(path1[0]) == tolower(path2[0])) ||
524 (!is_abs1 && !is_abs2);
525}
526
527/*
528 * Give path as relative to prefix.
529 *
530 * The strbuf may or may not be used, so do not assume it contains the
531 * returned path.
532 */
533const char *relative_path(const char *in, const char *prefix,
534 struct strbuf *sb)
535{
536 int in_len = in ? strlen(in) : 0;
537 int prefix_len = prefix ? strlen(prefix) : 0;
538 int in_off = 0;
539 int prefix_off = 0;
540 int i = 0, j = 0;
541
542 if (!in_len)
543 return "./";
544 else if (!prefix_len)
545 return in;
546
547 if (have_same_root(in, prefix)) {
548 /* bypass dos_drive, for "c:" is identical to "C:" */
549 if (has_dos_drive_prefix(in)) {
550 i = 2;
551 j = 2;
552 }
553 } else {
554 return in;
555 }
556
557 while (i < prefix_len && j < in_len && prefix[i] == in[j]) {
558 if (is_dir_sep(prefix[i])) {
559 while (is_dir_sep(prefix[i]))
560 i++;
561 while (is_dir_sep(in[j]))
562 j++;
563 prefix_off = i;
564 in_off = j;
565 } else {
566 i++;
567 j++;
568 }
569 }
570
571 if (
572 /* "prefix" seems like prefix of "in" */
573 i >= prefix_len &&
574 /*
575 * but "/foo" is not a prefix of "/foobar"
576 * (i.e. prefix not end with '/')
577 */
578 prefix_off < prefix_len) {
579 if (j >= in_len) {
580 /* in="/a/b", prefix="/a/b" */
581 in_off = in_len;
582 } else if (is_dir_sep(in[j])) {
583 /* in="/a/b/c", prefix="/a/b" */
584 while (is_dir_sep(in[j]))
585 j++;
586 in_off = j;
587 } else {
588 /* in="/a/bbb/c", prefix="/a/b" */
589 i = prefix_off;
590 }
591 } else if (
592 /* "in" is short than "prefix" */
593 j >= in_len &&
594 /* "in" not end with '/' */
595 in_off < in_len) {
596 if (is_dir_sep(prefix[i])) {
597 /* in="/a/b", prefix="/a/b/c/" */
598 while (is_dir_sep(prefix[i]))
599 i++;
600 in_off = in_len;
601 }
602 }
603 in += in_off;
604 in_len -= in_off;
605
606 if (i >= prefix_len) {
607 if (!in_len)
608 return "./";
609 else
610 return in;
611 }
612
613 strbuf_reset(sb);
614 strbuf_grow(sb, in_len);
615
616 while (i < prefix_len) {
617 if (is_dir_sep(prefix[i])) {
618 strbuf_addstr(sb, "../");
619 while (is_dir_sep(prefix[i]))
620 i++;
621 continue;
622 }
623 i++;
624 }
625 if (!is_dir_sep(prefix[prefix_len - 1]))
626 strbuf_addstr(sb, "../");
627
628 strbuf_addstr(sb, in);
629
630 return sb->buf;
631}
632
633/*
634 * A simpler implementation of relative_path
635 *
636 * Get relative path by removing "prefix" from "in". This function
637 * first appears in v1.5.6-1-g044bbbc, and makes git_dir shorter
638 * to increase performance when traversing the path to work_tree.
639 */
640const char *remove_leading_path(const char *in, const char *prefix)
641{
642 static char buf[PATH_MAX + 1];
643 int i = 0, j = 0;
644
645 if (!prefix || !prefix[0])
646 return in;
647 while (prefix[i]) {
648 if (is_dir_sep(prefix[i])) {
649 if (!is_dir_sep(in[j]))
650 return in;
651 while (is_dir_sep(prefix[i]))
652 i++;
653 while (is_dir_sep(in[j]))
654 j++;
655 continue;
656 } else if (in[j] != prefix[i]) {
657 return in;
658 }
659 i++;
660 j++;
661 }
662 if (
663 /* "/foo" is a prefix of "/foo" */
664 in[j] &&
665 /* "/foo" is not a prefix of "/foobar" */
666 !is_dir_sep(prefix[i-1]) && !is_dir_sep(in[j])
667 )
668 return in;
669 while (is_dir_sep(in[j]))
670 j++;
671 if (!in[j])
672 strcpy(buf, ".");
673 else
674 strcpy(buf, in + j);
675 return buf;
676}
677
678/*
679 * It is okay if dst == src, but they should not overlap otherwise.
680 *
681 * Performs the following normalizations on src, storing the result in dst:
682 * - Ensures that components are separated by '/' (Windows only)
683 * - Squashes sequences of '/'.
684 * - Removes "." components.
685 * - Removes ".." components, and the components the precede them.
686 * Returns failure (non-zero) if a ".." component appears as first path
687 * component anytime during the normalization. Otherwise, returns success (0).
688 *
689 * Note that this function is purely textual. It does not follow symlinks,
690 * verify the existence of the path, or make any system calls.
691 *
692 * prefix_len != NULL is for a specific case of prefix_pathspec():
693 * assume that src == dst and src[0..prefix_len-1] is already
694 * normalized, any time "../" eats up to the prefix_len part,
695 * prefix_len is reduced. In the end prefix_len is the remaining
696 * prefix that has not been overridden by user pathspec.
697 *
698 * NEEDSWORK: This function doesn't perform normalization w.r.t. trailing '/'.
699 * For everything but the root folder itself, the normalized path should not
700 * end with a '/', then the callers need to be fixed up accordingly.
701 *
702 */
703int normalize_path_copy_len(char *dst, const char *src, int *prefix_len)
704{
705 char *dst0;
706
707 if (has_dos_drive_prefix(src)) {
708 *dst++ = *src++;
709 *dst++ = *src++;
710 }
711 dst0 = dst;
712
713 if (is_dir_sep(*src)) {
714 *dst++ = '/';
715 while (is_dir_sep(*src))
716 src++;
717 }
718
719 for (;;) {
720 char c = *src;
721
722 /*
723 * A path component that begins with . could be
724 * special:
725 * (1) "." and ends -- ignore and terminate.
726 * (2) "./" -- ignore them, eat slash and continue.
727 * (3) ".." and ends -- strip one and terminate.
728 * (4) "../" -- strip one, eat slash and continue.
729 */
730 if (c == '.') {
731 if (!src[1]) {
732 /* (1) */
733 src++;
734 } else if (is_dir_sep(src[1])) {
735 /* (2) */
736 src += 2;
737 while (is_dir_sep(*src))
738 src++;
739 continue;
740 } else if (src[1] == '.') {
741 if (!src[2]) {
742 /* (3) */
743 src += 2;
744 goto up_one;
745 } else if (is_dir_sep(src[2])) {
746 /* (4) */
747 src += 3;
748 while (is_dir_sep(*src))
749 src++;
750 goto up_one;
751 }
752 }
753 }
754
755 /* copy up to the next '/', and eat all '/' */
756 while ((c = *src++) != '\0' && !is_dir_sep(c))
757 *dst++ = c;
758 if (is_dir_sep(c)) {
759 *dst++ = '/';
760 while (is_dir_sep(c))
761 c = *src++;
762 src--;
763 } else if (!c)
764 break;
765 continue;
766
767 up_one:
768 /*
769 * dst0..dst is prefix portion, and dst[-1] is '/';
770 * go up one level.
771 */
772 dst--; /* go to trailing '/' */
773 if (dst <= dst0)
774 return -1;
775 /* Windows: dst[-1] cannot be backslash anymore */
776 while (dst0 < dst && dst[-1] != '/')
777 dst--;
778 if (prefix_len && *prefix_len > dst - dst0)
779 *prefix_len = dst - dst0;
780 }
781 *dst = '\0';
782 return 0;
783}
784
785int normalize_path_copy(char *dst, const char *src)
786{
787 return normalize_path_copy_len(dst, src, NULL);
788}
789
790/*
791 * path = Canonical absolute path
792 * prefixes = string_list containing normalized, absolute paths without
793 * trailing slashes (except for the root directory, which is denoted by "/").
794 *
795 * Determines, for each path in prefixes, whether the "prefix"
796 * is an ancestor directory of path. Returns the length of the longest
797 * ancestor directory, excluding any trailing slashes, or -1 if no prefix
798 * is an ancestor. (Note that this means 0 is returned if prefixes is
799 * ["/"].) "/foo" is not considered an ancestor of "/foobar". Directories
800 * are not considered to be their own ancestors. path must be in a
801 * canonical form: empty components, or "." or ".." components are not
802 * allowed.
803 */
804int longest_ancestor_length(const char *path, struct string_list *prefixes)
805{
806 int i, max_len = -1;
807
808 if (!strcmp(path, "/"))
809 return -1;
810
811 for (i = 0; i < prefixes->nr; i++) {
812 const char *ceil = prefixes->items[i].string;
813 int len = strlen(ceil);
814
815 if (len == 1 && ceil[0] == '/')
816 len = 0; /* root matches anything, with length 0 */
817 else if (!strncmp(path, ceil, len) && path[len] == '/')
818 ; /* match of length len */
819 else
820 continue; /* no match */
821
822 if (len > max_len)
823 max_len = len;
824 }
825
826 return max_len;
827}
828
829/* strip arbitrary amount of directory separators at end of path */
830static inline int chomp_trailing_dir_sep(const char *path, int len)
831{
832 while (len && is_dir_sep(path[len - 1]))
833 len--;
834 return len;
835}
836
837/*
838 * If path ends with suffix (complete path components), returns the
839 * part before suffix (sans trailing directory separators).
840 * Otherwise returns NULL.
841 */
842char *strip_path_suffix(const char *path, const char *suffix)
843{
844 int path_len = strlen(path), suffix_len = strlen(suffix);
845
846 while (suffix_len) {
847 if (!path_len)
848 return NULL;
849
850 if (is_dir_sep(path[path_len - 1])) {
851 if (!is_dir_sep(suffix[suffix_len - 1]))
852 return NULL;
853 path_len = chomp_trailing_dir_sep(path, path_len);
854 suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
855 }
856 else if (path[--path_len] != suffix[--suffix_len])
857 return NULL;
858 }
859
860 if (path_len && !is_dir_sep(path[path_len - 1]))
861 return NULL;
862 return xstrndup(path, chomp_trailing_dir_sep(path, path_len));
863}
864
865int daemon_avoid_alias(const char *p)
866{
867 int sl, ndot;
868
869 /*
870 * This resurrects the belts and suspenders paranoia check by HPA
871 * done in <435560F7.4080006@zytor.com> thread, now enter_repo()
872 * does not do getcwd() based path canonicalization.
873 *
874 * sl becomes true immediately after seeing '/' and continues to
875 * be true as long as dots continue after that without intervening
876 * non-dot character.
877 */
878 if (!p || (*p != '/' && *p != '~'))
879 return -1;
880 sl = 1; ndot = 0;
881 p++;
882
883 while (1) {
884 char ch = *p++;
885 if (sl) {
886 if (ch == '.')
887 ndot++;
888 else if (ch == '/') {
889 if (ndot < 3)
890 /* reject //, /./ and /../ */
891 return -1;
892 ndot = 0;
893 }
894 else if (ch == 0) {
895 if (0 < ndot && ndot < 3)
896 /* reject /.$ and /..$ */
897 return -1;
898 return 0;
899 }
900 else
901 sl = ndot = 0;
902 }
903 else if (ch == 0)
904 return 0;
905 else if (ch == '/') {
906 sl = 1;
907 ndot = 0;
908 }
909 }
910}
911
912static int only_spaces_and_periods(const char *path, size_t len, size_t skip)
913{
914 if (len < skip)
915 return 0;
916 len -= skip;
917 path += skip;
918 while (len-- > 0) {
919 char c = *(path++);
920 if (c != ' ' && c != '.')
921 return 0;
922 }
923 return 1;
924}
925
926int is_ntfs_dotgit(const char *name)
927{
928 int len;
929
930 for (len = 0; ; len++)
931 if (!name[len] || name[len] == '\\' || is_dir_sep(name[len])) {
932 if (only_spaces_and_periods(name, len, 4) &&
933 !strncasecmp(name, ".git", 4))
934 return 1;
935 if (only_spaces_and_periods(name, len, 5) &&
936 !strncasecmp(name, "git~1", 5))
937 return 1;
938 if (name[len] != '\\')
939 return 0;
940 name += len + 1;
941 len = -1;
942 }
943}
944
945char *xdg_config_home(const char *filename)
946{
947 const char *home, *config_home;
948
949 assert(filename);
950 config_home = getenv("XDG_CONFIG_HOME");
951 if (config_home && *config_home)
952 return mkpathdup("%s/git/%s", config_home, filename);
953
954 home = getenv("HOME");
955 if (home)
956 return mkpathdup("%s/.config/git/%s", home, filename);
957 return NULL;
958}
959
960GIT_PATH_FUNC(git_path_cherry_pick_head, "CHERRY_PICK_HEAD")
961GIT_PATH_FUNC(git_path_revert_head, "REVERT_HEAD")
962GIT_PATH_FUNC(git_path_squash_msg, "SQUASH_MSG")
963GIT_PATH_FUNC(git_path_merge_msg, "MERGE_MSG")
964GIT_PATH_FUNC(git_path_merge_rr, "MERGE_RR")
965GIT_PATH_FUNC(git_path_merge_mode, "MERGE_MODE")
966GIT_PATH_FUNC(git_path_merge_head, "MERGE_HEAD")
967GIT_PATH_FUNC(git_path_fetch_head, "FETCH_HEAD")
968GIT_PATH_FUNC(git_path_shallow, "shallow")