2 * I'm tired of doing "vsnprintf()" etc just to open a
3 * file, so here's a "return static buffer with printf"
6 * It's obviously not thread-safe. Sue me. But it's quite
7 * useful for doing things like
9 * f = open(mkpath("%s/%s.git", base, name), O_RDONLY);
11 * which is what it's designed for.
15 static char bad_path[] = "/bad-path/";
17 static char *get_pathname(void)
19 static char pathname_array[4][PATH_MAX];
21 return pathname_array[3 & ++index];
24 static char *cleanup_path(char *path)
27 if (!memcmp(path, "./", 2)) {
35 char *mksnpath(char *buf, size_t n, const char *fmt, ...)
41 len = vsnprintf(buf, n, fmt, args);
44 snprintf(buf, n, bad_path);
47 return cleanup_path(buf);
50 char *git_snpath(char *buf, size_t n, const char *fmt, ...)
52 const char *git_dir = get_git_dir();
56 len = strlen(git_dir);
59 memcpy(buf, git_dir, len);
60 if (len && !is_dir_sep(git_dir[len-1]))
63 len += vsnprintf(buf + len, n - len, fmt, args);
67 return cleanup_path(buf);
69 snprintf(buf, n, bad_path);
73 char *mkpath(const char *fmt, ...)
77 char *pathname = get_pathname();
80 len = vsnprintf(pathname, PATH_MAX, fmt, args);
84 return cleanup_path(pathname);
87 char *git_path(const char *fmt, ...)
89 const char *git_dir = get_git_dir();
90 char *pathname = get_pathname();
94 len = strlen(git_dir);
95 if (len > PATH_MAX-100)
97 memcpy(pathname, git_dir, len);
98 if (len && git_dir[len-1] != '/')
99 pathname[len++] = '/';
101 len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
105 return cleanup_path(pathname);
109 /* git_mkstemp() - create tmp file honoring TMPDIR variable */
110 int git_mkstemp(char *path, size_t len, const char *template)
115 tmp = getenv("TMPDIR");
118 n = snprintf(path, len, "%s/%s", tmp, template);
120 errno = ENAMETOOLONG;
123 return mkstemp(path);
127 int validate_headref(const char *path)
130 char *buf, buffer[256];
131 unsigned char sha1[20];
135 if (lstat(path, &st) < 0)
138 /* Make sure it is a "refs/.." symlink */
139 if (S_ISLNK(st.st_mode)) {
140 len = readlink(path, buffer, sizeof(buffer)-1);
141 if (len >= 5 && !memcmp("refs/", buffer, 5))
147 * Anything else, just open it and try to see if it is a symbolic ref.
149 fd = open(path, O_RDONLY);
152 len = read_in_full(fd, buffer, sizeof(buffer)-1);
156 * Is it a symbolic ref?
160 if (!memcmp("ref:", buffer, 4)) {
163 while (len && isspace(*buf))
165 if (len >= 5 && !memcmp("refs/", buf, 5))
170 * Is this a detached HEAD?
172 if (!get_sha1_hex(buffer, sha1))
178 static char *user_path(char *buf, char *path, int sz)
184 if (!path || path[0] != '~')
187 slash = strchr(path, '/');
188 if (path[0] == '/' || !path[0]) {
189 pw = getpwuid(getuid());
200 if (!pw || !pw->pw_dir || sz <= strlen(pw->pw_dir))
202 baselen = strlen(pw->pw_dir);
203 memcpy(buf, pw->pw_dir, baselen);
204 while ((1 < baselen) && (buf[baselen-1] == '/')) {
208 if (slash && slash[1]) {
210 if (sz <= baselen + len)
212 memcpy(buf + baselen, slash, len + 1);
218 * First, one directory to try is determined by the following algorithm.
220 * (0) If "strict" is given, the path is used as given and no DWIM is
222 * (1) "~/path" to mean path under the running user's home directory;
223 * (2) "~user/path" to mean path under named user's home directory;
224 * (3) "relative/path" to mean cwd relative directory; or
225 * (4) "/absolute/path" to mean absolute directory.
227 * Unless "strict" is given, we try access() for existence of "%s.git/.git",
228 * "%s/.git", "%s.git", "%s" in this order. The first one that exists is
231 * Second, we try chdir() to that. Upon failure, we return NULL.
233 * Then, we try if the current directory is a valid git repository.
234 * Upon failure, we return NULL.
236 * If all goes well, we return the directory we used to chdir() (but
237 * before ~user is expanded), avoiding getcwd() resolving symbolic
238 * links. User relative paths are also returned as they are given,
239 * except DWIM suffixing.
241 char *enter_repo(char *path, int strict)
243 static char used_path[PATH_MAX];
244 static char validated_path[PATH_MAX];
250 static const char *suffix[] = {
251 ".git/.git", "/.git", ".git", "", NULL,
253 int len = strlen(path);
255 while ((1 < len) && (path[len-1] == '/')) {
261 if (path[0] == '~') {
262 if (!user_path(used_path, path, PATH_MAX))
264 strcpy(validated_path, path);
267 else if (PATH_MAX - 10 < len)
270 path = strcpy(used_path, path);
271 strcpy(validated_path, path);
274 for (i = 0; suffix[i]; i++) {
275 strcpy(path + len, suffix[i]);
276 if (!access(path, F_OK)) {
277 strcat(validated_path, suffix[i]);
281 if (!suffix[i] || chdir(path))
283 path = validated_path;
285 else if (chdir(path))
288 if (access("objects", X_OK) == 0 && access("refs", X_OK) == 0 &&
289 validate_headref("HEAD") == 0) {
290 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
291 check_repository_format();
298 int adjust_shared_perm(const char *path)
303 if (!shared_repository)
305 if (lstat(path, &st) < 0)
309 if (shared_repository) {
310 int tweak = shared_repository;
311 if (!(mode & S_IWUSR))
315 /* Preserve old PERM_UMASK behaviour */
321 mode |= FORCE_DIR_SET_GID;
323 /* Copy read bits to execute bits */
324 mode |= (shared_repository & 0444) >> 2;
327 if ((mode & st.st_mode) != mode && chmod(path, mode) < 0)
332 const char *make_relative_path(const char *abs, const char *base)
334 static char buf[PATH_MAX + 1];
338 baselen = strlen(base);
339 if (prefixcmp(abs, base))
341 if (abs[baselen] == '/')
343 else if (base[baselen - 1] != '/')
345 strcpy(buf, abs + baselen);
350 * path = absolute path
351 * buf = buffer of at least max(2, strlen(path)+1) bytes
352 * It is okay if buf == path, but they should not overlap otherwise.
354 * Performs the following normalizations on path, storing the result in buf:
355 * - Removes trailing slashes.
356 * - Removes empty components.
357 * - Removes "." components.
358 * - Removes ".." components, and the components the precede them.
359 * "" and paths that contain only slashes are normalized to "/".
360 * Returns the length of the output.
362 * Note that this function is purely textual. It does not follow symlinks,
363 * verify the existence of the path, or make any system calls.
365 int normalize_absolute_path(char *buf, const char *path)
367 const char *comp_start = path, *comp_end = path;
373 while (*comp_start) {
374 assert(*comp_start == '/');
375 while (*++comp_end && *comp_end != '/')
377 comp_len = comp_end - comp_start;
379 if (!strncmp("/", comp_start, comp_len) ||
380 !strncmp("/.", comp_start, comp_len))
383 if (!strncmp("/..", comp_start, comp_len)) {
384 while (dst > buf && *--dst != '/')
389 memcpy(dst, comp_start, comp_len);
392 comp_start = comp_end;
403 * path = Canonical absolute path
404 * prefix_list = Colon-separated list of absolute paths
406 * Determines, for each path in prefix_list, whether the "prefix" really
407 * is an ancestor directory of path. Returns the length of the longest
408 * ancestor directory, excluding any trailing slashes, or -1 if no prefix
409 * is an ancestor. (Note that this means 0 is returned if prefix_list is
410 * "/".) "/foo" is not considered an ancestor of "/foobar". Directories
411 * are not considered to be their own ancestors. path must be in a
412 * canonical form: empty components, or "." or ".." components are not
413 * allowed. prefix_list may be null, which is like "".
415 int longest_ancestor_length(const char *path, const char *prefix_list)
417 char buf[PATH_MAX+1];
418 const char *ceil, *colon;
419 int len, max_len = -1;
421 if (prefix_list == NULL || !strcmp(path, "/"))
424 for (colon = ceil = prefix_list; *colon; ceil = colon+1) {
425 for (colon = ceil; *colon && *colon != ':'; colon++);
427 if (len == 0 || len > PATH_MAX || !is_absolute_path(ceil))
429 strlcpy(buf, ceil, len+1);
430 len = normalize_absolute_path(buf, buf);
431 /* Strip "trailing slashes" from "/". */
435 if (!strncmp(path, buf, len) &&