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 *mkpath(const char *fmt, ...)
54 char *pathname = get_pathname();
57 len = vsnprintf(pathname, PATH_MAX, fmt, args);
61 return cleanup_path(pathname);
64 char *git_path(const char *fmt, ...)
66 const char *git_dir = get_git_dir();
67 char *pathname = get_pathname();
71 len = strlen(git_dir);
72 if (len > PATH_MAX-100)
74 memcpy(pathname, git_dir, len);
75 if (len && git_dir[len-1] != '/')
76 pathname[len++] = '/';
78 len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
82 return cleanup_path(pathname);
86 /* git_mkstemp() - create tmp file honoring TMPDIR variable */
87 int git_mkstemp(char *path, size_t len, const char *template)
92 tmp = getenv("TMPDIR");
95 n = snprintf(path, len, "%s/%s", tmp, template);
100 return mkstemp(path);
104 int validate_headref(const char *path)
107 char *buf, buffer[256];
108 unsigned char sha1[20];
112 if (lstat(path, &st) < 0)
115 /* Make sure it is a "refs/.." symlink */
116 if (S_ISLNK(st.st_mode)) {
117 len = readlink(path, buffer, sizeof(buffer)-1);
118 if (len >= 5 && !memcmp("refs/", buffer, 5))
124 * Anything else, just open it and try to see if it is a symbolic ref.
126 fd = open(path, O_RDONLY);
129 len = read_in_full(fd, buffer, sizeof(buffer)-1);
133 * Is it a symbolic ref?
137 if (!memcmp("ref:", buffer, 4)) {
140 while (len && isspace(*buf))
142 if (len >= 5 && !memcmp("refs/", buf, 5))
147 * Is this a detached HEAD?
149 if (!get_sha1_hex(buffer, sha1))
155 static char *user_path(char *buf, char *path, int sz)
161 if (!path || path[0] != '~')
164 slash = strchr(path, '/');
165 if (path[0] == '/' || !path[0]) {
166 pw = getpwuid(getuid());
177 if (!pw || !pw->pw_dir || sz <= strlen(pw->pw_dir))
179 baselen = strlen(pw->pw_dir);
180 memcpy(buf, pw->pw_dir, baselen);
181 while ((1 < baselen) && (buf[baselen-1] == '/')) {
185 if (slash && slash[1]) {
187 if (sz <= baselen + len)
189 memcpy(buf + baselen, slash, len + 1);
195 * First, one directory to try is determined by the following algorithm.
197 * (0) If "strict" is given, the path is used as given and no DWIM is
199 * (1) "~/path" to mean path under the running user's home directory;
200 * (2) "~user/path" to mean path under named user's home directory;
201 * (3) "relative/path" to mean cwd relative directory; or
202 * (4) "/absolute/path" to mean absolute directory.
204 * Unless "strict" is given, we try access() for existence of "%s.git/.git",
205 * "%s/.git", "%s.git", "%s" in this order. The first one that exists is
208 * Second, we try chdir() to that. Upon failure, we return NULL.
210 * Then, we try if the current directory is a valid git repository.
211 * Upon failure, we return NULL.
213 * If all goes well, we return the directory we used to chdir() (but
214 * before ~user is expanded), avoiding getcwd() resolving symbolic
215 * links. User relative paths are also returned as they are given,
216 * except DWIM suffixing.
218 char *enter_repo(char *path, int strict)
220 static char used_path[PATH_MAX];
221 static char validated_path[PATH_MAX];
227 static const char *suffix[] = {
228 ".git/.git", "/.git", ".git", "", NULL,
230 int len = strlen(path);
232 while ((1 < len) && (path[len-1] == '/')) {
238 if (path[0] == '~') {
239 if (!user_path(used_path, path, PATH_MAX))
241 strcpy(validated_path, path);
244 else if (PATH_MAX - 10 < len)
247 path = strcpy(used_path, path);
248 strcpy(validated_path, path);
251 for (i = 0; suffix[i]; i++) {
252 strcpy(path + len, suffix[i]);
253 if (!access(path, F_OK)) {
254 strcat(validated_path, suffix[i]);
258 if (!suffix[i] || chdir(path))
260 path = validated_path;
262 else if (chdir(path))
265 if (access("objects", X_OK) == 0 && access("refs", X_OK) == 0 &&
266 validate_headref("HEAD") == 0) {
267 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
268 check_repository_format();
275 int adjust_shared_perm(const char *path)
280 if (!shared_repository)
282 if (lstat(path, &st) < 0)
286 if (shared_repository) {
287 int tweak = shared_repository;
288 if (!(mode & S_IWUSR))
292 /* Preserve old PERM_UMASK behaviour */
298 mode |= FORCE_DIR_SET_GID;
300 /* Copy read bits to execute bits */
301 mode |= (shared_repository & 0444) >> 2;
304 if ((mode & st.st_mode) != mode && chmod(path, mode) < 0)
309 const char *make_relative_path(const char *abs, const char *base)
311 static char buf[PATH_MAX + 1];
315 baselen = strlen(base);
316 if (prefixcmp(abs, base))
318 if (abs[baselen] == '/')
320 else if (base[baselen - 1] != '/')
322 strcpy(buf, abs + baselen);
327 * path = absolute path
328 * buf = buffer of at least max(2, strlen(path)+1) bytes
329 * It is okay if buf == path, but they should not overlap otherwise.
331 * Performs the following normalizations on path, storing the result in buf:
332 * - Removes trailing slashes.
333 * - Removes empty components.
334 * - Removes "." components.
335 * - Removes ".." components, and the components the precede them.
336 * "" and paths that contain only slashes are normalized to "/".
337 * Returns the length of the output.
339 * Note that this function is purely textual. It does not follow symlinks,
340 * verify the existence of the path, or make any system calls.
342 int normalize_absolute_path(char *buf, const char *path)
344 const char *comp_start = path, *comp_end = path;
350 while (*comp_start) {
351 assert(*comp_start == '/');
352 while (*++comp_end && *comp_end != '/')
354 comp_len = comp_end - comp_start;
356 if (!strncmp("/", comp_start, comp_len) ||
357 !strncmp("/.", comp_start, comp_len))
360 if (!strncmp("/..", comp_start, comp_len)) {
361 while (dst > buf && *--dst != '/')
366 memcpy(dst, comp_start, comp_len);
369 comp_start = comp_end;
380 * path = Canonical absolute path
381 * prefix_list = Colon-separated list of absolute paths
383 * Determines, for each path in prefix_list, whether the "prefix" really
384 * is an ancestor directory of path. Returns the length of the longest
385 * ancestor directory, excluding any trailing slashes, or -1 if no prefix
386 * is an ancestor. (Note that this means 0 is returned if prefix_list is
387 * "/".) "/foo" is not considered an ancestor of "/foobar". Directories
388 * are not considered to be their own ancestors. path must be in a
389 * canonical form: empty components, or "." or ".." components are not
390 * allowed. prefix_list may be null, which is like "".
392 int longest_ancestor_length(const char *path, const char *prefix_list)
394 char buf[PATH_MAX+1];
395 const char *ceil, *colon;
396 int len, max_len = -1;
398 if (prefix_list == NULL || !strcmp(path, "/"))
401 for (colon = ceil = prefix_list; *colon; ceil = colon+1) {
402 for (colon = ceil; *colon && *colon != ':'; colon++);
404 if (len == 0 || len > PATH_MAX || !is_absolute_path(ceil))
406 strlcpy(buf, ceil, len+1);
407 len = normalize_absolute_path(buf, buf);
408 /* Strip "trailing slashes" from "/". */
412 if (!strncmp(path, buf, len) &&