2 * Utilities for paths and pathnames
6 #include "string-list.h"
8 static int get_st_mode_bits(const char *path, int *mode)
11 if (lstat(path, &st) < 0)
17 static char bad_path[] = "/bad-path/";
19 static char *get_pathname(void)
21 static char pathname_array[4][PATH_MAX];
23 return pathname_array[3 & ++index];
26 static char *cleanup_path(char *path)
29 if (!memcmp(path, "./", 2)) {
37 char *mksnpath(char *buf, size_t n, const char *fmt, ...)
43 len = vsnprintf(buf, n, fmt, args);
46 strlcpy(buf, bad_path, n);
49 return cleanup_path(buf);
52 static char *vsnpath(char *buf, size_t n, const char *fmt, va_list args)
54 const char *git_dir = get_git_dir();
57 len = strlen(git_dir);
60 memcpy(buf, git_dir, len);
61 if (len && !is_dir_sep(git_dir[len-1]))
63 len += vsnprintf(buf + len, n - len, fmt, args);
66 return cleanup_path(buf);
68 strlcpy(buf, bad_path, n);
72 char *git_snpath(char *buf, size_t n, const char *fmt, ...)
77 ret = vsnpath(buf, n, fmt, args);
82 char *git_pathdup(const char *fmt, ...)
84 char path[PATH_MAX], *ret;
87 ret = vsnpath(path, sizeof(path), fmt, args);
92 char *mkpathdup(const char *fmt, ...)
95 struct strbuf sb = STRBUF_INIT;
99 strbuf_vaddf(&sb, fmt, args);
101 path = xstrdup(cleanup_path(sb.buf));
107 char *mkpath(const char *fmt, ...)
111 char *pathname = get_pathname();
114 len = vsnprintf(pathname, PATH_MAX, fmt, args);
118 return cleanup_path(pathname);
121 char *git_path(const char *fmt, ...)
123 char *pathname = get_pathname();
128 ret = vsnpath(pathname, PATH_MAX, fmt, args);
133 void home_config_paths(char **global, char **xdg, char *file)
135 char *xdg_home = getenv("XDG_CONFIG_HOME");
136 char *home = getenv("HOME");
137 char *to_free = NULL;
144 to_free = mkpathdup("%s/.config", home);
148 *global = mkpathdup("%s/.gitconfig", home);
154 *xdg = mkpathdup("%s/git/%s", xdg_home, file);
159 char *git_path_submodule(const char *path, const char *fmt, ...)
161 char *pathname = get_pathname();
162 struct strbuf buf = STRBUF_INIT;
168 if (len > PATH_MAX-100)
171 strbuf_addstr(&buf, path);
172 if (len && path[len-1] != '/')
173 strbuf_addch(&buf, '/');
174 strbuf_addstr(&buf, ".git");
176 git_dir = read_gitfile(buf.buf);
179 strbuf_addstr(&buf, git_dir);
181 strbuf_addch(&buf, '/');
183 if (buf.len >= PATH_MAX)
185 memcpy(pathname, buf.buf, buf.len + 1);
187 strbuf_release(&buf);
188 len = strlen(pathname);
191 len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
195 return cleanup_path(pathname);
198 int validate_headref(const char *path)
201 char *buf, buffer[256];
202 unsigned char sha1[20];
206 if (lstat(path, &st) < 0)
209 /* Make sure it is a "refs/.." symlink */
210 if (S_ISLNK(st.st_mode)) {
211 len = readlink(path, buffer, sizeof(buffer)-1);
212 if (len >= 5 && !memcmp("refs/", buffer, 5))
218 * Anything else, just open it and try to see if it is a symbolic ref.
220 fd = open(path, O_RDONLY);
223 len = read_in_full(fd, buffer, sizeof(buffer)-1);
227 * Is it a symbolic ref?
231 if (!memcmp("ref:", buffer, 4)) {
234 while (len && isspace(*buf))
236 if (len >= 5 && !memcmp("refs/", buf, 5))
241 * Is this a detached HEAD?
243 if (!get_sha1_hex(buffer, sha1))
249 static struct passwd *getpw_str(const char *username, size_t len)
252 char *username_z = xmalloc(len + 1);
253 memcpy(username_z, username, len);
254 username_z[len] = '\0';
255 pw = getpwnam(username_z);
261 * Return a string with ~ and ~user expanded via getpw*. If buf != NULL,
262 * then it is a newly allocated string. Returns NULL on getpw failure or
265 char *expand_user_path(const char *path)
267 struct strbuf user_path = STRBUF_INIT;
268 const char *first_slash = strchrnul(path, '/');
269 const char *to_copy = path;
273 if (path[0] == '~') {
274 const char *username = path + 1;
275 size_t username_len = first_slash - username;
276 if (username_len == 0) {
277 const char *home = getenv("HOME");
280 strbuf_add(&user_path, home, strlen(home));
282 struct passwd *pw = getpw_str(username, username_len);
285 strbuf_add(&user_path, pw->pw_dir, strlen(pw->pw_dir));
287 to_copy = first_slash;
289 strbuf_add(&user_path, to_copy, strlen(to_copy));
290 return strbuf_detach(&user_path, NULL);
292 strbuf_release(&user_path);
297 * First, one directory to try is determined by the following algorithm.
299 * (0) If "strict" is given, the path is used as given and no DWIM is
301 * (1) "~/path" to mean path under the running user's home directory;
302 * (2) "~user/path" to mean path under named user's home directory;
303 * (3) "relative/path" to mean cwd relative directory; or
304 * (4) "/absolute/path" to mean absolute directory.
306 * Unless "strict" is given, we try access() for existence of "%s.git/.git",
307 * "%s/.git", "%s.git", "%s" in this order. The first one that exists is
310 * Second, we try chdir() to that. Upon failure, we return NULL.
312 * Then, we try if the current directory is a valid git repository.
313 * Upon failure, we return NULL.
315 * If all goes well, we return the directory we used to chdir() (but
316 * before ~user is expanded), avoiding getcwd() resolving symbolic
317 * links. User relative paths are also returned as they are given,
318 * except DWIM suffixing.
320 const char *enter_repo(const char *path, int strict)
322 static char used_path[PATH_MAX];
323 static char validated_path[PATH_MAX];
329 static const char *suffix[] = {
330 "/.git", "", ".git/.git", ".git", NULL,
333 int len = strlen(path);
335 while ((1 < len) && (path[len-1] == '/'))
340 strncpy(used_path, path, len); used_path[len] = 0 ;
341 strcpy(validated_path, used_path);
343 if (used_path[0] == '~') {
344 char *newpath = expand_user_path(used_path);
345 if (!newpath || (PATH_MAX - 10 < strlen(newpath))) {
350 * Copy back into the static buffer. A pity
351 * since newpath was not bounded, but other
352 * branches of the if are limited by PATH_MAX
355 strcpy(used_path, newpath); free(newpath);
357 else if (PATH_MAX - 10 < len)
359 len = strlen(used_path);
360 for (i = 0; suffix[i]; i++) {
362 strcpy(used_path + len, suffix[i]);
363 if (!stat(used_path, &st) &&
364 (S_ISREG(st.st_mode) ||
365 (S_ISDIR(st.st_mode) && is_git_directory(used_path)))) {
366 strcat(validated_path, suffix[i]);
372 gitfile = read_gitfile(used_path) ;
374 strcpy(used_path, gitfile);
375 if (chdir(used_path))
377 path = validated_path;
379 else if (chdir(path))
382 if (access("objects", X_OK) == 0 && access("refs", X_OK) == 0 &&
383 validate_headref("HEAD") == 0) {
385 check_repository_format();
392 static int calc_shared_perm(int mode)
396 if (shared_repository < 0)
397 tweak = -shared_repository;
399 tweak = shared_repository;
401 if (!(mode & S_IWUSR))
404 /* Copy read bits to execute bits */
405 tweak |= (tweak & 0444) >> 2;
406 if (shared_repository < 0)
407 mode = (mode & ~0777) | tweak;
415 int adjust_shared_perm(const char *path)
417 int old_mode, new_mode;
419 if (!shared_repository)
421 if (get_st_mode_bits(path, &old_mode) < 0)
424 new_mode = calc_shared_perm(old_mode);
425 if (S_ISDIR(old_mode)) {
426 /* Copy read bits to execute bits */
427 new_mode |= (new_mode & 0444) >> 2;
428 new_mode |= FORCE_DIR_SET_GID;
431 if (((old_mode ^ new_mode) & ~S_IFMT) &&
432 chmod(path, (new_mode & ~S_IFMT)) < 0)
437 const char *relative_path(const char *abs, const char *base)
439 static char buf[PATH_MAX + 1];
442 if (!base || !base[0])
445 if (is_dir_sep(base[i])) {
446 if (!is_dir_sep(abs[j]))
448 while (is_dir_sep(base[i]))
450 while (is_dir_sep(abs[j]))
453 } else if (abs[j] != base[i]) {
460 /* "/foo" is a prefix of "/foo" */
462 /* "/foo" is not a prefix of "/foobar" */
463 !is_dir_sep(base[i-1]) && !is_dir_sep(abs[j])
466 while (is_dir_sep(abs[j]))
471 strcpy(buf, abs + j);
476 * It is okay if dst == src, but they should not overlap otherwise.
478 * Performs the following normalizations on src, storing the result in dst:
479 * - Ensures that components are separated by '/' (Windows only)
480 * - Squashes sequences of '/'.
481 * - Removes "." components.
482 * - Removes ".." components, and the components the precede them.
483 * Returns failure (non-zero) if a ".." component appears as first path
484 * component anytime during the normalization. Otherwise, returns success (0).
486 * Note that this function is purely textual. It does not follow symlinks,
487 * verify the existence of the path, or make any system calls.
489 int normalize_path_copy(char *dst, const char *src)
493 if (has_dos_drive_prefix(src)) {
499 if (is_dir_sep(*src)) {
501 while (is_dir_sep(*src))
509 * A path component that begins with . could be
511 * (1) "." and ends -- ignore and terminate.
512 * (2) "./" -- ignore them, eat slash and continue.
513 * (3) ".." and ends -- strip one and terminate.
514 * (4) "../" -- strip one, eat slash and continue.
520 } else if (is_dir_sep(src[1])) {
523 while (is_dir_sep(*src))
526 } else if (src[1] == '.') {
531 } else if (is_dir_sep(src[2])) {
534 while (is_dir_sep(*src))
541 /* copy up to the next '/', and eat all '/' */
542 while ((c = *src++) != '\0' && !is_dir_sep(c))
546 while (is_dir_sep(c))
555 * dst0..dst is prefix portion, and dst[-1] is '/';
558 dst--; /* go to trailing '/' */
561 /* Windows: dst[-1] cannot be backslash anymore */
562 while (dst0 < dst && dst[-1] != '/')
570 * path = Canonical absolute path
571 * prefixes = string_list containing normalized, absolute paths without
572 * trailing slashes (except for the root directory, which is denoted by "/").
574 * Determines, for each path in prefixes, whether the "prefix"
575 * is an ancestor directory of path. Returns the length of the longest
576 * ancestor directory, excluding any trailing slashes, or -1 if no prefix
577 * is an ancestor. (Note that this means 0 is returned if prefixes is
578 * ["/"].) "/foo" is not considered an ancestor of "/foobar". Directories
579 * are not considered to be their own ancestors. path must be in a
580 * canonical form: empty components, or "." or ".." components are not
583 int longest_ancestor_length(const char *path, struct string_list *prefixes)
587 if (!strcmp(path, "/"))
590 for (i = 0; i < prefixes->nr; i++) {
591 const char *ceil = prefixes->items[i].string;
592 int len = strlen(ceil);
594 if (len == 1 && ceil[0] == '/')
595 len = 0; /* root matches anything, with length 0 */
596 else if (!strncmp(path, ceil, len) && path[len] == '/')
597 ; /* match of length len */
599 continue; /* no match */
608 /* strip arbitrary amount of directory separators at end of path */
609 static inline int chomp_trailing_dir_sep(const char *path, int len)
611 while (len && is_dir_sep(path[len - 1]))
617 * If path ends with suffix (complete path components), returns the
618 * part before suffix (sans trailing directory separators).
619 * Otherwise returns NULL.
621 char *strip_path_suffix(const char *path, const char *suffix)
623 int path_len = strlen(path), suffix_len = strlen(suffix);
629 if (is_dir_sep(path[path_len - 1])) {
630 if (!is_dir_sep(suffix[suffix_len - 1]))
632 path_len = chomp_trailing_dir_sep(path, path_len);
633 suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
635 else if (path[--path_len] != suffix[--suffix_len])
639 if (path_len && !is_dir_sep(path[path_len - 1]))
641 return xstrndup(path, chomp_trailing_dir_sep(path, path_len));
644 int daemon_avoid_alias(const char *p)
649 * This resurrects the belts and suspenders paranoia check by HPA
650 * done in <435560F7.4080006@zytor.com> thread, now enter_repo()
651 * does not do getcwd() based path canonicalization.
653 * sl becomes true immediately after seeing '/' and continues to
654 * be true as long as dots continue after that without intervening
657 if (!p || (*p != '/' && *p != '~'))
667 else if (ch == '/') {
669 /* reject //, /./ and /../ */
674 if (0 < ndot && ndot < 3)
675 /* reject /.$ and /..$ */
684 else if (ch == '/') {
691 int offset_1st_component(const char *path)
693 if (has_dos_drive_prefix(path))
694 return 2 + is_dir_sep(path[2]);
695 return is_dir_sep(path[0]);