2 * Utilities for paths and pathnames
6 #include "string-list.h"
8 #ifndef get_st_mode_bits
10 * The replacement lstat(2) we use on Cygwin is incomplete and
11 * may return wrong permission bits. Most of the time we do not care,
12 * but the callsites of this wrapper do care.
14 int get_st_mode_bits(const char *path, int *mode)
17 if (lstat(path, &st) < 0)
24 static char bad_path[] = "/bad-path/";
26 static char *get_pathname(void)
28 static char pathname_array[4][PATH_MAX];
30 return pathname_array[3 & ++index];
33 static char *cleanup_path(char *path)
36 if (!memcmp(path, "./", 2)) {
44 char *mksnpath(char *buf, size_t n, const char *fmt, ...)
50 len = vsnprintf(buf, n, fmt, args);
53 strlcpy(buf, bad_path, n);
56 return cleanup_path(buf);
59 static char *vsnpath(char *buf, size_t n, const char *fmt, va_list args)
61 const char *git_dir = get_git_dir();
64 len = strlen(git_dir);
67 memcpy(buf, git_dir, len);
68 if (len && !is_dir_sep(git_dir[len-1]))
70 len += vsnprintf(buf + len, n - len, fmt, args);
73 return cleanup_path(buf);
75 strlcpy(buf, bad_path, n);
79 char *git_snpath(char *buf, size_t n, const char *fmt, ...)
84 ret = vsnpath(buf, n, fmt, args);
89 char *git_pathdup(const char *fmt, ...)
91 char path[PATH_MAX], *ret;
94 ret = vsnpath(path, sizeof(path), fmt, args);
99 char *mkpathdup(const char *fmt, ...)
102 struct strbuf sb = STRBUF_INIT;
106 strbuf_vaddf(&sb, fmt, args);
108 path = xstrdup(cleanup_path(sb.buf));
114 char *mkpath(const char *fmt, ...)
118 char *pathname = get_pathname();
121 len = vsnprintf(pathname, PATH_MAX, fmt, args);
125 return cleanup_path(pathname);
128 char *git_path(const char *fmt, ...)
130 char *pathname = get_pathname();
135 ret = vsnpath(pathname, PATH_MAX, fmt, args);
140 void home_config_paths(char **global, char **xdg, char *file)
142 char *xdg_home = getenv("XDG_CONFIG_HOME");
143 char *home = getenv("HOME");
144 char *to_free = NULL;
151 to_free = mkpathdup("%s/.config", home);
155 *global = mkpathdup("%s/.gitconfig", home);
161 *xdg = mkpathdup("%s/git/%s", xdg_home, file);
166 char *git_path_submodule(const char *path, const char *fmt, ...)
168 char *pathname = get_pathname();
169 struct strbuf buf = STRBUF_INIT;
175 if (len > PATH_MAX-100)
178 strbuf_addstr(&buf, path);
179 if (len && path[len-1] != '/')
180 strbuf_addch(&buf, '/');
181 strbuf_addstr(&buf, ".git");
183 git_dir = read_gitfile(buf.buf);
186 strbuf_addstr(&buf, git_dir);
188 strbuf_addch(&buf, '/');
190 if (buf.len >= PATH_MAX)
192 memcpy(pathname, buf.buf, buf.len + 1);
194 strbuf_release(&buf);
195 len = strlen(pathname);
198 len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
202 return cleanup_path(pathname);
205 int validate_headref(const char *path)
208 char *buf, buffer[256];
209 unsigned char sha1[20];
213 if (lstat(path, &st) < 0)
216 /* Make sure it is a "refs/.." symlink */
217 if (S_ISLNK(st.st_mode)) {
218 len = readlink(path, buffer, sizeof(buffer)-1);
219 if (len >= 5 && !memcmp("refs/", buffer, 5))
225 * Anything else, just open it and try to see if it is a symbolic ref.
227 fd = open(path, O_RDONLY);
230 len = read_in_full(fd, buffer, sizeof(buffer)-1);
234 * Is it a symbolic ref?
238 if (!memcmp("ref:", buffer, 4)) {
241 while (len && isspace(*buf))
243 if (len >= 5 && !memcmp("refs/", buf, 5))
248 * Is this a detached HEAD?
250 if (!get_sha1_hex(buffer, sha1))
256 static struct passwd *getpw_str(const char *username, size_t len)
259 char *username_z = xmalloc(len + 1);
260 memcpy(username_z, username, len);
261 username_z[len] = '\0';
262 pw = getpwnam(username_z);
268 * Return a string with ~ and ~user expanded via getpw*. If buf != NULL,
269 * then it is a newly allocated string. Returns NULL on getpw failure or
272 char *expand_user_path(const char *path)
274 struct strbuf user_path = STRBUF_INIT;
275 const char *first_slash = strchrnul(path, '/');
276 const char *to_copy = path;
280 if (path[0] == '~') {
281 const char *username = path + 1;
282 size_t username_len = first_slash - username;
283 if (username_len == 0) {
284 const char *home = getenv("HOME");
287 strbuf_add(&user_path, home, strlen(home));
289 struct passwd *pw = getpw_str(username, username_len);
292 strbuf_add(&user_path, pw->pw_dir, strlen(pw->pw_dir));
294 to_copy = first_slash;
296 strbuf_add(&user_path, to_copy, strlen(to_copy));
297 return strbuf_detach(&user_path, NULL);
299 strbuf_release(&user_path);
304 * First, one directory to try is determined by the following algorithm.
306 * (0) If "strict" is given, the path is used as given and no DWIM is
308 * (1) "~/path" to mean path under the running user's home directory;
309 * (2) "~user/path" to mean path under named user's home directory;
310 * (3) "relative/path" to mean cwd relative directory; or
311 * (4) "/absolute/path" to mean absolute directory.
313 * Unless "strict" is given, we try access() for existence of "%s.git/.git",
314 * "%s/.git", "%s.git", "%s" in this order. The first one that exists is
317 * Second, we try chdir() to that. Upon failure, we return NULL.
319 * Then, we try if the current directory is a valid git repository.
320 * Upon failure, we return NULL.
322 * If all goes well, we return the directory we used to chdir() (but
323 * before ~user is expanded), avoiding getcwd() resolving symbolic
324 * links. User relative paths are also returned as they are given,
325 * except DWIM suffixing.
327 const char *enter_repo(const char *path, int strict)
329 static char used_path[PATH_MAX];
330 static char validated_path[PATH_MAX];
336 static const char *suffix[] = {
337 "/.git", "", ".git/.git", ".git", NULL,
340 int len = strlen(path);
342 while ((1 < len) && (path[len-1] == '/'))
347 strncpy(used_path, path, len); used_path[len] = 0 ;
348 strcpy(validated_path, used_path);
350 if (used_path[0] == '~') {
351 char *newpath = expand_user_path(used_path);
352 if (!newpath || (PATH_MAX - 10 < strlen(newpath))) {
357 * Copy back into the static buffer. A pity
358 * since newpath was not bounded, but other
359 * branches of the if are limited by PATH_MAX
362 strcpy(used_path, newpath); free(newpath);
364 else if (PATH_MAX - 10 < len)
366 len = strlen(used_path);
367 for (i = 0; suffix[i]; i++) {
369 strcpy(used_path + len, suffix[i]);
370 if (!stat(used_path, &st) &&
371 (S_ISREG(st.st_mode) ||
372 (S_ISDIR(st.st_mode) && is_git_directory(used_path)))) {
373 strcat(validated_path, suffix[i]);
379 gitfile = read_gitfile(used_path) ;
381 strcpy(used_path, gitfile);
382 if (chdir(used_path))
384 path = validated_path;
386 else if (chdir(path))
389 if (access("objects", X_OK) == 0 && access("refs", X_OK) == 0 &&
390 validate_headref("HEAD") == 0) {
392 check_repository_format();
399 static int calc_shared_perm(int mode)
403 if (shared_repository < 0)
404 tweak = -shared_repository;
406 tweak = shared_repository;
408 if (!(mode & S_IWUSR))
411 /* Copy read bits to execute bits */
412 tweak |= (tweak & 0444) >> 2;
413 if (shared_repository < 0)
414 mode = (mode & ~0777) | tweak;
422 int adjust_shared_perm(const char *path)
424 int old_mode, new_mode;
426 if (!shared_repository)
428 if (get_st_mode_bits(path, &old_mode) < 0)
431 new_mode = calc_shared_perm(old_mode);
432 if (S_ISDIR(old_mode)) {
433 /* Copy read bits to execute bits */
434 new_mode |= (new_mode & 0444) >> 2;
435 new_mode |= FORCE_DIR_SET_GID;
438 if (((old_mode ^ new_mode) & ~S_IFMT) &&
439 chmod(path, (new_mode & ~S_IFMT)) < 0)
445 * Give path as relative to prefix.
447 * The strbuf may or may not be used, so do not assume it contains the
450 const char *relative_path(const char *in, const char *prefix,
453 int in_len = in ? strlen(in) : 0;
454 int prefix_len = prefix ? strlen(prefix) : 0;
461 else if (!prefix_len)
464 while (i < prefix_len && j < in_len && prefix[i] == in[j]) {
465 if (is_dir_sep(prefix[i])) {
466 while (is_dir_sep(prefix[i]))
468 while (is_dir_sep(in[j]))
479 /* "prefix" seems like prefix of "in" */
482 * but "/foo" is not a prefix of "/foobar"
483 * (i.e. prefix not end with '/')
485 prefix_off < prefix_len) {
487 /* in="/a/b", prefix="/a/b" */
489 } else if (is_dir_sep(in[j])) {
490 /* in="/a/b/c", prefix="/a/b" */
491 while (is_dir_sep(in[j]))
495 /* in="/a/bbb/c", prefix="/a/b" */
499 /* "in" is short than "prefix" */
501 /* "in" not end with '/' */
503 if (is_dir_sep(prefix[i])) {
504 /* in="/a/b", prefix="/a/b/c/" */
505 while (is_dir_sep(prefix[i]))
513 if (i >= prefix_len) {
521 strbuf_grow(sb, in_len);
523 while (i < prefix_len) {
524 if (is_dir_sep(prefix[i])) {
525 strbuf_addstr(sb, "../");
526 while (is_dir_sep(prefix[i]))
532 if (!is_dir_sep(prefix[prefix_len - 1]))
533 strbuf_addstr(sb, "../");
535 strbuf_addstr(sb, in);
541 * It is okay if dst == src, but they should not overlap otherwise.
543 * Performs the following normalizations on src, storing the result in dst:
544 * - Ensures that components are separated by '/' (Windows only)
545 * - Squashes sequences of '/'.
546 * - Removes "." components.
547 * - Removes ".." components, and the components the precede them.
548 * Returns failure (non-zero) if a ".." component appears as first path
549 * component anytime during the normalization. Otherwise, returns success (0).
551 * Note that this function is purely textual. It does not follow symlinks,
552 * verify the existence of the path, or make any system calls.
554 int normalize_path_copy(char *dst, const char *src)
558 if (has_dos_drive_prefix(src)) {
564 if (is_dir_sep(*src)) {
566 while (is_dir_sep(*src))
574 * A path component that begins with . could be
576 * (1) "." and ends -- ignore and terminate.
577 * (2) "./" -- ignore them, eat slash and continue.
578 * (3) ".." and ends -- strip one and terminate.
579 * (4) "../" -- strip one, eat slash and continue.
585 } else if (is_dir_sep(src[1])) {
588 while (is_dir_sep(*src))
591 } else if (src[1] == '.') {
596 } else if (is_dir_sep(src[2])) {
599 while (is_dir_sep(*src))
606 /* copy up to the next '/', and eat all '/' */
607 while ((c = *src++) != '\0' && !is_dir_sep(c))
611 while (is_dir_sep(c))
620 * dst0..dst is prefix portion, and dst[-1] is '/';
623 dst--; /* go to trailing '/' */
626 /* Windows: dst[-1] cannot be backslash anymore */
627 while (dst0 < dst && dst[-1] != '/')
635 * path = Canonical absolute path
636 * prefixes = string_list containing normalized, absolute paths without
637 * trailing slashes (except for the root directory, which is denoted by "/").
639 * Determines, for each path in prefixes, whether the "prefix"
640 * is an ancestor directory of path. Returns the length of the longest
641 * ancestor directory, excluding any trailing slashes, or -1 if no prefix
642 * is an ancestor. (Note that this means 0 is returned if prefixes is
643 * ["/"].) "/foo" is not considered an ancestor of "/foobar". Directories
644 * are not considered to be their own ancestors. path must be in a
645 * canonical form: empty components, or "." or ".." components are not
648 int longest_ancestor_length(const char *path, struct string_list *prefixes)
652 if (!strcmp(path, "/"))
655 for (i = 0; i < prefixes->nr; i++) {
656 const char *ceil = prefixes->items[i].string;
657 int len = strlen(ceil);
659 if (len == 1 && ceil[0] == '/')
660 len = 0; /* root matches anything, with length 0 */
661 else if (!strncmp(path, ceil, len) && path[len] == '/')
662 ; /* match of length len */
664 continue; /* no match */
673 /* strip arbitrary amount of directory separators at end of path */
674 static inline int chomp_trailing_dir_sep(const char *path, int len)
676 while (len && is_dir_sep(path[len - 1]))
682 * If path ends with suffix (complete path components), returns the
683 * part before suffix (sans trailing directory separators).
684 * Otherwise returns NULL.
686 char *strip_path_suffix(const char *path, const char *suffix)
688 int path_len = strlen(path), suffix_len = strlen(suffix);
694 if (is_dir_sep(path[path_len - 1])) {
695 if (!is_dir_sep(suffix[suffix_len - 1]))
697 path_len = chomp_trailing_dir_sep(path, path_len);
698 suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
700 else if (path[--path_len] != suffix[--suffix_len])
704 if (path_len && !is_dir_sep(path[path_len - 1]))
706 return xstrndup(path, chomp_trailing_dir_sep(path, path_len));
709 int daemon_avoid_alias(const char *p)
714 * This resurrects the belts and suspenders paranoia check by HPA
715 * done in <435560F7.4080006@zytor.com> thread, now enter_repo()
716 * does not do getcwd() based path canonicalization.
718 * sl becomes true immediately after seeing '/' and continues to
719 * be true as long as dots continue after that without intervening
722 if (!p || (*p != '/' && *p != '~'))
732 else if (ch == '/') {
734 /* reject //, /./ and /../ */
739 if (0 < ndot && ndot < 3)
740 /* reject /.$ and /..$ */
749 else if (ch == '/') {
756 int offset_1st_component(const char *path)
758 if (has_dos_drive_prefix(path))
759 return 2 + is_dir_sep(path[2]);
760 return is_dir_sep(path[0]);