8 unsigned char flag; /* ISSYMREF? ISPACKED? */
9 unsigned char sha1[20];
10 char name[FLEX_ARRAY];
13 static const char *parse_ref_line(char *line, unsigned char *sha1)
16 * 42: the answer to everything.
18 * In this case, it happens to be the answer to
19 * 40 (length of sha1 hex representation)
20 * +1 (space in between hex and name)
21 * +1 (newline at the end of the line)
23 int len = strlen(line) - 42;
27 if (get_sha1_hex(line, sha1) < 0)
29 if (!isspace(line[40]))
34 if (line[len] != '\n')
40 static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
41 int flag, struct ref_list *list)
44 struct ref_list **p = &list, *entry;
46 /* Find the place to insert the ref into.. */
47 while ((entry = *p) != NULL) {
48 int cmp = strcmp(entry->name, name);
52 /* Same as existing entry? */
58 /* Allocate it and add it in.. */
59 len = strlen(name) + 1;
60 entry = xmalloc(sizeof(struct ref_list) + len);
61 hashcpy(entry->sha1, sha1);
62 memcpy(entry->name, name, len);
69 static struct ref_list *get_packed_refs(void)
71 static int did_refs = 0;
72 static struct ref_list *refs = NULL;
75 FILE *f = fopen(git_path("packed-refs"), "r");
77 struct ref_list *list = NULL;
78 char refline[PATH_MAX];
79 while (fgets(refline, sizeof(refline), f)) {
80 unsigned char sha1[20];
81 const char *name = parse_ref_line(refline, sha1);
84 list = add_ref(name, sha1, REF_ISPACKED, list);
94 static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
96 DIR *dir = opendir(git_path("%s", base));
100 int baselen = strlen(base);
101 char *ref = xmalloc(baselen + 257);
103 memcpy(ref, base, baselen);
104 if (baselen && base[baselen-1] != '/')
105 ref[baselen++] = '/';
107 while ((de = readdir(dir)) != NULL) {
108 unsigned char sha1[20];
113 if (de->d_name[0] == '.')
115 namelen = strlen(de->d_name);
118 if (has_extension(de->d_name, ".lock"))
120 memcpy(ref + baselen, de->d_name, namelen+1);
121 if (stat(git_path("%s", ref), &st) < 0)
123 if (S_ISDIR(st.st_mode)) {
124 list = get_ref_dir(ref, list);
127 if (!resolve_ref(ref, sha1, 1, &flag)) {
128 error("%s points nowhere!", ref);
131 list = add_ref(ref, sha1, flag, list);
139 static struct ref_list *get_loose_refs(void)
141 static int did_refs = 0;
142 static struct ref_list *refs = NULL;
145 refs = get_ref_dir("refs", NULL);
151 /* We allow "recursive" symbolic refs. Only within reason, though */
154 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
156 int depth = MAXDEPTH, len;
158 static char ref_buffer[256];
164 const char *path = git_path("%s", ref);
172 /* Special case: non-existing file.
173 * Not having the refs/heads/new-branch is OK
174 * if we are writing into it, so is .git/HEAD
175 * that points at refs/heads/master still to be
176 * born. It is NOT OK if we are resolving for
179 if (lstat(path, &st) < 0) {
180 struct ref_list *list = get_packed_refs();
182 if (!strcmp(ref, list->name)) {
183 hashcpy(sha1, list->sha1);
185 *flag |= REF_ISPACKED;
190 if (reading || errno != ENOENT)
196 /* Follow "normalized" - ie "refs/.." symlinks by hand */
197 if (S_ISLNK(st.st_mode)) {
198 len = readlink(path, buffer, sizeof(buffer)-1);
199 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
201 strcpy(ref_buffer, buffer);
204 *flag |= REF_ISSYMREF;
210 * Anything else, just open it and try to use it as
213 fd = open(path, O_RDONLY);
216 len = read(fd, buffer, sizeof(buffer)-1);
220 * Is it a symbolic ref?
222 if (len < 4 || memcmp("ref:", buffer, 4))
226 while (len && isspace(*buf))
228 while (len && isspace(buf[len-1]))
231 memcpy(ref_buffer, buf, len + 1);
234 *flag |= REF_ISSYMREF;
236 if (len < 40 || get_sha1_hex(buffer, sha1))
241 int create_symref(const char *ref_target, const char *refs_heads_master)
243 const char *lockpath;
245 int fd, len, written;
246 const char *git_HEAD = git_path("%s", ref_target);
248 #ifndef NO_SYMLINK_HEAD
249 if (prefer_symlink_refs) {
251 if (!symlink(refs_heads_master, git_HEAD))
253 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
257 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
258 if (sizeof(ref) <= len) {
259 error("refname too long: %s", refs_heads_master);
262 lockpath = mkpath("%s.lock", git_HEAD);
263 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
264 written = write(fd, ref, len);
266 if (written != len) {
268 error("Unable to write to %s", lockpath);
271 if (rename(lockpath, git_HEAD) < 0) {
273 error("Unable to create %s", git_HEAD);
276 if (adjust_shared_perm(git_HEAD)) {
278 error("Unable to fix permissions on %s", lockpath);
284 int read_ref(const char *ref, unsigned char *sha1)
286 if (resolve_ref(ref, sha1, 1, NULL))
291 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
295 struct ref_list *packed = get_packed_refs();
296 struct ref_list *loose = get_loose_refs();
298 while (packed && loose) {
299 struct ref_list *entry;
300 int cmp = strcmp(packed->name, loose->name);
302 packed = packed->next;
310 packed = packed->next;
312 if (strncmp(base, entry->name, trim))
314 if (is_null_sha1(entry->sha1))
316 if (!has_sha1_file(entry->sha1)) {
317 error("%s does not point to a valid object!", entry->name);
320 retval = fn(entry->name + trim, entry->sha1,
321 entry->flag, cb_data);
326 packed = packed ? packed : loose;
328 if (!strncmp(base, packed->name, trim)) {
329 retval = fn(packed->name + trim, packed->sha1,
330 packed->flag, cb_data);
334 packed = packed->next;
339 int head_ref(each_ref_fn fn, void *cb_data)
341 unsigned char sha1[20];
344 if (resolve_ref("HEAD", sha1, 1, &flag))
345 return fn("HEAD", sha1, flag, cb_data);
349 int for_each_ref(each_ref_fn fn, void *cb_data)
351 return do_for_each_ref("refs/", fn, 0, cb_data);
354 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
356 return do_for_each_ref("refs/tags/", fn, 10, cb_data);
359 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
361 return do_for_each_ref("refs/heads/", fn, 11, cb_data);
364 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
366 return do_for_each_ref("refs/remotes/", fn, 13, cb_data);
369 /* NEEDSWORK: This is only used by ssh-upload and it should go; the
370 * caller should do resolve_ref or read_ref like everybody else. Or
371 * maybe everybody else should use get_ref_sha1() instead of doing
374 int get_ref_sha1(const char *ref, unsigned char *sha1)
376 if (check_ref_format(ref))
378 return read_ref(mkpath("refs/%s", ref), sha1);
382 * Make sure "ref" is something reasonable to have under ".git/refs/";
383 * We do not like it if:
385 * - any path component of it begins with ".", or
386 * - it has double dots "..", or
387 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
388 * - it ends with a "/".
391 static inline int bad_ref_char(int ch)
393 return (((unsigned) ch) <= ' ' ||
394 ch == '~' || ch == '^' || ch == ':' ||
395 /* 2.13 Pattern Matching Notation */
396 ch == '?' || ch == '*' || ch == '[');
399 int check_ref_format(const char *ref)
402 const char *cp = ref;
406 while ((ch = *cp++) == '/')
407 ; /* tolerate duplicated slashes */
409 return -1; /* should not end with slashes */
411 /* we are at the beginning of the path component */
412 if (ch == '.' || bad_ref_char(ch))
415 /* scan the rest of the path component */
416 while ((ch = *cp++) != 0) {
417 if (bad_ref_char(ch))
421 if (ch == '.' && *cp == '.')
427 return -1; /* at least of form "heads/blah" */
433 static struct ref_lock *verify_lock(struct ref_lock *lock,
434 const unsigned char *old_sha1, int mustexist)
436 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
437 error("Can't verify ref %s", lock->ref_name);
441 if (hashcmp(lock->old_sha1, old_sha1)) {
442 error("Ref %s is at %s but expected %s", lock->ref_name,
443 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
450 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int mustexist)
453 const char *orig_ref = ref;
454 struct ref_lock *lock;
457 lock = xcalloc(1, sizeof(struct ref_lock));
460 ref = resolve_ref(ref, lock->old_sha1, mustexist, NULL);
462 int last_errno = errno;
463 error("unable to resolve reference %s: %s",
464 orig_ref, strerror(errno));
469 lock->lk = xcalloc(1, sizeof(struct lock_file));
471 lock->ref_name = xstrdup(ref);
472 lock->log_file = xstrdup(git_path("logs/%s", ref));
473 ref_file = git_path("%s", ref);
474 lock->force_write = lstat(ref_file, &st) && errno == ENOENT;
476 if (safe_create_leading_directories(ref_file))
477 die("unable to create directory for %s", ref_file);
478 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, 1);
480 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
483 struct ref_lock *lock_ref_sha1(const char *ref,
484 const unsigned char *old_sha1, int mustexist)
486 char refpath[PATH_MAX];
487 if (check_ref_format(ref))
489 strcpy(refpath, mkpath("refs/%s", ref));
490 return lock_ref_sha1_basic(refpath, old_sha1, mustexist);
493 struct ref_lock *lock_any_ref_for_update(const char *ref,
494 const unsigned char *old_sha1, int mustexist)
496 return lock_ref_sha1_basic(ref, old_sha1, mustexist);
499 void unlock_ref(struct ref_lock *lock)
501 if (lock->lock_fd >= 0) {
502 close(lock->lock_fd);
503 /* Do not free lock->lk -- atexit() still looks at them */
505 rollback_lock_file(lock->lk);
507 free(lock->ref_name);
508 free(lock->log_file);
512 static int log_ref_write(struct ref_lock *lock,
513 const unsigned char *sha1, const char *msg)
515 int logfd, written, oflags = O_APPEND | O_WRONLY;
516 unsigned maxlen, len;
518 const char *committer;
520 if (log_all_ref_updates) {
521 if (safe_create_leading_directories(lock->log_file) < 0)
522 return error("unable to create directory for %s",
527 logfd = open(lock->log_file, oflags, 0666);
529 if (!log_all_ref_updates && errno == ENOENT)
531 return error("Unable to append to %s: %s",
532 lock->log_file, strerror(errno));
535 committer = git_committer_info(1);
537 maxlen = strlen(committer) + strlen(msg) + 2*40 + 5;
538 logrec = xmalloc(maxlen);
539 len = snprintf(logrec, maxlen, "%s %s %s\t%s\n",
540 sha1_to_hex(lock->old_sha1),
546 maxlen = strlen(committer) + 2*40 + 4;
547 logrec = xmalloc(maxlen);
548 len = snprintf(logrec, maxlen, "%s %s %s\n",
549 sha1_to_hex(lock->old_sha1),
553 written = len <= maxlen ? write(logfd, logrec, len) : -1;
557 return error("Unable to append to %s", lock->log_file);
561 int write_ref_sha1(struct ref_lock *lock,
562 const unsigned char *sha1, const char *logmsg)
564 static char term = '\n';
568 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
572 if (write(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
573 write(lock->lock_fd, &term, 1) != 1
574 || close(lock->lock_fd) < 0) {
575 error("Couldn't write %s", lock->lk->filename);
579 if (log_ref_write(lock, sha1, logmsg) < 0) {
583 if (commit_lock_file(lock->lk)) {
584 error("Couldn't set %s", lock->ref_name);
593 int read_ref_at(const char *ref, unsigned long at_time, unsigned char *sha1)
595 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
600 unsigned char logged_sha1[20];
602 logfile = git_path("logs/%s", ref);
603 logfd = open(logfile, O_RDONLY, 0);
605 die("Unable to read log %s: %s", logfile, strerror(errno));
608 die("Log %s is empty.", logfile);
609 logdata = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, logfd, 0);
613 rec = logend = logdata + st.st_size;
614 while (logdata < rec) {
615 if (logdata < rec && *(rec-1) == '\n')
618 while (logdata < rec && *(rec-1) != '\n') {
624 die("Log %s is corrupt.", logfile);
625 date = strtoul(lastgt + 1, &tz_c, 10);
626 if (date <= at_time) {
628 if (get_sha1_hex(lastrec, logged_sha1))
629 die("Log %s is corrupt.", logfile);
630 if (get_sha1_hex(rec + 41, sha1))
631 die("Log %s is corrupt.", logfile);
632 if (hashcmp(logged_sha1, sha1)) {
633 tz = strtoul(tz_c, NULL, 10);
635 "warning: Log %s has gap after %s.\n",
636 logfile, show_rfc2822_date(date, tz));
639 else if (date == at_time) {
640 if (get_sha1_hex(rec + 41, sha1))
641 die("Log %s is corrupt.", logfile);
644 if (get_sha1_hex(rec + 41, logged_sha1))
645 die("Log %s is corrupt.", logfile);
646 if (hashcmp(logged_sha1, sha1)) {
647 tz = strtoul(tz_c, NULL, 10);
649 "warning: Log %s unexpectedly ended on %s.\n",
650 logfile, show_rfc2822_date(date, tz));
653 munmap((void*)logdata, st.st_size);
660 while (rec < logend && *rec != '>' && *rec != '\n')
662 if (rec == logend || *rec == '\n')
663 die("Log %s is corrupt.", logfile);
664 date = strtoul(rec + 1, &tz_c, 10);
665 tz = strtoul(tz_c, NULL, 10);
666 if (get_sha1_hex(logdata, sha1))
667 die("Log %s is corrupt.", logfile);
668 munmap((void*)logdata, st.st_size);
669 fprintf(stderr, "warning: Log %s only goes back to %s.\n",
670 logfile, show_rfc2822_date(date, tz));