6 /* We allow "recursive" symbolic refs. Only within reason, though */
9 const char *resolve_ref(const char *path, unsigned char *sha1, int reading)
11 int depth = MAXDEPTH, len;
22 /* Special case: non-existing file.
23 * Not having the refs/heads/new-branch is OK
24 * if we are writing into it, so is .git/HEAD
25 * that points at refs/heads/master still to be
26 * born. It is NOT OK if we are resolving for
29 if (lstat(path, &st) < 0) {
30 if (reading || errno != ENOENT)
36 /* Follow "normalized" - ie "refs/.." symlinks by hand */
37 if (S_ISLNK(st.st_mode)) {
38 len = readlink(path, buffer, sizeof(buffer)-1);
39 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
40 path = git_path("%.*s", len, buffer);
46 * Anything else, just open it and try to use it as
49 fd = open(path, O_RDONLY);
52 len = read(fd, buffer, sizeof(buffer)-1);
56 * Is it a symbolic ref?
58 if (len < 4 || memcmp("ref:", buffer, 4))
62 while (len && isspace(*buf))
64 while (len && isspace(buf[len-1]))
66 path = git_path("%.*s", len, buf);
68 if (len < 40 || get_sha1_hex(buffer, sha1))
73 int create_symref(const char *git_HEAD, const char *refs_heads_master)
79 #ifndef NO_SYMLINK_HEAD
80 if (prefer_symlink_refs) {
82 if (!symlink(refs_heads_master, git_HEAD))
84 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
88 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
89 if (sizeof(ref) <= len) {
90 error("refname too long: %s", refs_heads_master);
93 lockpath = mkpath("%s.lock", git_HEAD);
94 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
95 written = write(fd, ref, len);
99 error("Unable to write to %s", lockpath);
102 if (rename(lockpath, git_HEAD) < 0) {
104 error("Unable to create %s", git_HEAD);
110 int read_ref(const char *filename, unsigned char *sha1)
112 if (resolve_ref(filename, sha1, 1))
117 static int do_for_each_ref(const char *base, int (*fn)(const char *path, const unsigned char *sha1), int trim)
120 DIR *dir = opendir(git_path("%s", base));
124 int baselen = strlen(base);
125 char *path = xmalloc(baselen + 257);
127 if (!strncmp(base, "./", 2)) {
131 memcpy(path, base, baselen);
132 if (baselen && base[baselen-1] != '/')
133 path[baselen++] = '/';
135 while ((de = readdir(dir)) != NULL) {
136 unsigned char sha1[20];
140 if (de->d_name[0] == '.')
142 namelen = strlen(de->d_name);
145 if (namelen>5 && !strcmp(de->d_name+namelen-5,".lock"))
147 memcpy(path + baselen, de->d_name, namelen+1);
148 if (stat(git_path("%s", path), &st) < 0)
150 if (S_ISDIR(st.st_mode)) {
151 retval = do_for_each_ref(path, fn, trim);
156 if (read_ref(git_path("%s", path), sha1) < 0) {
157 error("%s points nowhere!", path);
160 if (!has_sha1_file(sha1)) {
161 error("%s does not point to a valid "
162 "commit object!", path);
165 retval = fn(path + trim, sha1);
175 int head_ref(int (*fn)(const char *path, const unsigned char *sha1))
177 unsigned char sha1[20];
178 if (!read_ref(git_path("HEAD"), sha1))
179 return fn("HEAD", sha1);
183 int for_each_ref(int (*fn)(const char *path, const unsigned char *sha1))
185 return do_for_each_ref("refs", fn, 0);
188 int for_each_tag_ref(int (*fn)(const char *path, const unsigned char *sha1))
190 return do_for_each_ref("refs/tags", fn, 10);
193 int for_each_branch_ref(int (*fn)(const char *path, const unsigned char *sha1))
195 return do_for_each_ref("refs/heads", fn, 11);
198 int for_each_remote_ref(int (*fn)(const char *path, const unsigned char *sha1))
200 return do_for_each_ref("refs/remotes", fn, 13);
203 int get_ref_sha1(const char *ref, unsigned char *sha1)
205 if (check_ref_format(ref))
207 return read_ref(git_path("refs/%s", ref), sha1);
211 * Make sure "ref" is something reasonable to have under ".git/refs/";
212 * We do not like it if:
214 * - any path component of it begins with ".", or
215 * - it has double dots "..", or
216 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
217 * - it ends with a "/".
220 static inline int bad_ref_char(int ch)
222 return (((unsigned) ch) <= ' ' ||
223 ch == '~' || ch == '^' || ch == ':' ||
224 /* 2.13 Pattern Matching Notation */
225 ch == '?' || ch == '*' || ch == '[');
228 int check_ref_format(const char *ref)
231 const char *cp = ref;
235 while ((ch = *cp++) == '/')
236 ; /* tolerate duplicated slashes */
238 return -1; /* should not end with slashes */
240 /* we are at the beginning of the path component */
241 if (ch == '.' || bad_ref_char(ch))
244 /* scan the rest of the path component */
245 while ((ch = *cp++) != 0) {
246 if (bad_ref_char(ch))
250 if (ch == '.' && *cp == '.')
256 return -1; /* at least of form "heads/blah" */
262 static struct ref_lock* verify_lock(struct ref_lock *lock,
263 const unsigned char *old_sha1, int mustexist)
266 int nr, fd = open(lock->ref_file, O_RDONLY);
267 if (fd < 0 && (mustexist || errno != ENOENT)) {
268 error("Can't verify ref %s", lock->ref_file);
272 nr = read(fd, buf, 40);
274 if (nr != 40 || get_sha1_hex(buf, lock->old_sha1) < 0) {
275 error("Can't verify ref %s", lock->ref_file);
279 if (memcmp(lock->old_sha1, old_sha1, 20)) {
280 error("Ref %s is at %s but expected %s", lock->ref_file,
281 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
288 static struct ref_lock* lock_ref_sha1_basic(const char *path,
290 const unsigned char *old_sha1, int mustexist)
292 struct ref_lock *lock;
295 lock = xcalloc(1, sizeof(struct ref_lock));
298 plen = strlen(path) - plen;
299 path = resolve_ref(path, lock->old_sha1, mustexist);
305 lock->ref_file = strdup(path);
306 lock->lock_file = strdup(mkpath("%s.lock", lock->ref_file));
307 lock->log_file = strdup(git_path("logs/%s", lock->ref_file + plen));
308 lock->force_write = lstat(lock->ref_file, &st) && errno == ENOENT;
310 if (safe_create_leading_directories(lock->lock_file))
311 die("unable to create directory for %s", lock->lock_file);
312 lock->lock_fd = open(lock->lock_file,
313 O_WRONLY | O_CREAT | O_EXCL, 0666);
314 if (lock->lock_fd < 0) {
315 error("Couldn't open lock file %s: %s",
316 lock->lock_file, strerror(errno));
321 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
324 struct ref_lock* lock_ref_sha1(const char *ref,
325 const unsigned char *old_sha1, int mustexist)
327 if (check_ref_format(ref))
329 return lock_ref_sha1_basic(git_path("refs/%s", ref),
330 5 + strlen(ref), old_sha1, mustexist);
333 struct ref_lock* lock_any_ref_for_update(const char *ref,
334 const unsigned char *old_sha1, int mustexist)
336 return lock_ref_sha1_basic(git_path("%s", ref),
337 strlen(ref), old_sha1, mustexist);
340 void unlock_ref (struct ref_lock *lock)
342 if (lock->lock_fd >= 0) {
343 close(lock->lock_fd);
344 unlink(lock->lock_file);
347 free(lock->ref_file);
349 free(lock->lock_file);
351 free(lock->log_file);
355 static int log_ref_write(struct ref_lock *lock,
356 const unsigned char *sha1, const char *msg)
358 int logfd, written, oflags = O_APPEND | O_WRONLY;
359 unsigned maxlen, len;
361 const char *comitter;
363 if (log_all_ref_updates) {
364 if (safe_create_leading_directories(lock->log_file) < 0)
365 return error("unable to create directory for %s",
370 logfd = open(lock->log_file, oflags, 0666);
372 if (!log_all_ref_updates && errno == ENOENT)
374 return error("Unable to append to %s: %s",
375 lock->log_file, strerror(errno));
379 comitter = git_committer_info(1);
381 maxlen = strlen(comitter) + strlen(msg) + 2*40 + 5;
382 logrec = xmalloc(maxlen);
383 len = snprintf(logrec, maxlen, "%s %s %s\t%s\n",
384 sha1_to_hex(lock->old_sha1),
389 maxlen = strlen(comitter) + 2*40 + 4;
390 logrec = xmalloc(maxlen);
391 len = snprintf(logrec, maxlen, "%s %s %s\n",
392 sha1_to_hex(lock->old_sha1),
396 written = len <= maxlen ? write(logfd, logrec, len) : -1;
400 return error("Unable to append to %s", lock->log_file);
404 int write_ref_sha1(struct ref_lock *lock,
405 const unsigned char *sha1, const char *logmsg)
407 static char term = '\n';
411 if (!lock->force_write && !memcmp(lock->old_sha1, sha1, 20)) {
415 if (write(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
416 write(lock->lock_fd, &term, 1) != 1
417 || close(lock->lock_fd) < 0) {
418 error("Couldn't write %s", lock->lock_file);
422 if (log_ref_write(lock, sha1, logmsg) < 0) {
426 if (rename(lock->lock_file, lock->ref_file) < 0) {
427 error("Couldn't set %s", lock->ref_file);
436 int read_ref_at(const char *ref, unsigned long at_time, unsigned char *sha1)
438 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
443 unsigned char logged_sha1[20];
445 logfile = git_path("logs/%s", ref);
446 logfd = open(logfile, O_RDONLY, 0);
448 die("Unable to read log %s: %s", logfile, strerror(errno));
451 die("Log %s is empty.", logfile);
452 logdata = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, logfd, 0);
456 rec = logend = logdata + st.st_size;
457 while (logdata < rec) {
458 if (logdata < rec && *(rec-1) == '\n')
461 while (logdata < rec && *(rec-1) != '\n') {
467 die("Log %s is corrupt.", logfile);
468 date = strtoul(lastgt + 1, &tz_c, 10);
469 if (date <= at_time) {
471 if (get_sha1_hex(lastrec, logged_sha1))
472 die("Log %s is corrupt.", logfile);
473 if (get_sha1_hex(rec + 41, sha1))
474 die("Log %s is corrupt.", logfile);
475 if (memcmp(logged_sha1, sha1, 20)) {
476 tz = strtoul(tz_c, NULL, 10);
478 "warning: Log %s has gap after %s.\n",
479 logfile, show_rfc2822_date(date, tz));
481 } else if (date == at_time) {
482 if (get_sha1_hex(rec + 41, sha1))
483 die("Log %s is corrupt.", logfile);
485 if (get_sha1_hex(rec + 41, logged_sha1))
486 die("Log %s is corrupt.", logfile);
487 if (memcmp(logged_sha1, sha1, 20)) {
488 tz = strtoul(tz_c, NULL, 10);
490 "warning: Log %s unexpectedly ended on %s.\n",
491 logfile, show_rfc2822_date(date, tz));
494 munmap((void*)logdata, st.st_size);
501 while (rec < logend && *rec != '>' && *rec != '\n')
503 if (rec == logend || *rec == '\n')
504 die("Log %s is corrupt.", logfile);
505 date = strtoul(rec + 1, &tz_c, 10);
506 tz = strtoul(tz_c, NULL, 10);
507 if (get_sha1_hex(logdata, sha1))
508 die("Log %s is corrupt.", logfile);
509 munmap((void*)logdata, st.st_size);
510 fprintf(stderr, "warning: Log %s only goes back to %s.\n",
511 logfile, show_rfc2822_date(date, tz));