delay progress display when checking out files
[git/dscho.git] / refs.c
blob89876bff871d007a6675f5790ce8cb34fe21fb39
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
6 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
7 #define REF_KNOWS_PEELED 04
9 struct ref_list {
10 struct ref_list *next;
11 unsigned char flag; /* ISSYMREF? ISPACKED? */
12 unsigned char sha1[20];
13 unsigned char peeled[20];
14 char name[FLEX_ARRAY];
17 static const char *parse_ref_line(char *line, unsigned char *sha1)
20 * 42: the answer to everything.
22 * In this case, it happens to be the answer to
23 * 40 (length of sha1 hex representation)
24 * +1 (space in between hex and name)
25 * +1 (newline at the end of the line)
27 int len = strlen(line) - 42;
29 if (len <= 0)
30 return NULL;
31 if (get_sha1_hex(line, sha1) < 0)
32 return NULL;
33 if (!isspace(line[40]))
34 return NULL;
35 line += 41;
36 if (isspace(*line))
37 return NULL;
38 if (line[len] != '\n')
39 return NULL;
40 line[len] = 0;
42 return line;
45 static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
46 int flag, struct ref_list *list,
47 struct ref_list **new_entry)
49 int len;
50 struct ref_list *entry;
52 /* Allocate it and add it in.. */
53 len = strlen(name) + 1;
54 entry = xmalloc(sizeof(struct ref_list) + len);
55 hashcpy(entry->sha1, sha1);
56 hashclr(entry->peeled);
57 memcpy(entry->name, name, len);
58 entry->flag = flag;
59 entry->next = list;
60 if (new_entry)
61 *new_entry = entry;
62 return entry;
65 /* merge sort the ref list */
66 static struct ref_list *sort_ref_list(struct ref_list *list)
68 int psize, qsize, last_merge_count, cmp;
69 struct ref_list *p, *q, *l, *e;
70 struct ref_list *new_list = list;
71 int k = 1;
72 int merge_count = 0;
74 if (!list)
75 return list;
77 do {
78 last_merge_count = merge_count;
79 merge_count = 0;
81 psize = 0;
83 p = new_list;
84 q = new_list;
85 new_list = NULL;
86 l = NULL;
88 while (p) {
89 merge_count++;
91 while (psize < k && q->next) {
92 q = q->next;
93 psize++;
95 qsize = k;
97 while ((psize > 0) || (qsize > 0 && q)) {
98 if (qsize == 0 || !q) {
99 e = p;
100 p = p->next;
101 psize--;
102 } else if (psize == 0) {
103 e = q;
104 q = q->next;
105 qsize--;
106 } else {
107 cmp = strcmp(q->name, p->name);
108 if (cmp < 0) {
109 e = q;
110 q = q->next;
111 qsize--;
112 } else if (cmp > 0) {
113 e = p;
114 p = p->next;
115 psize--;
116 } else {
117 if (hashcmp(q->sha1, p->sha1))
118 die("Duplicated ref, and SHA1s don't match: %s",
119 q->name);
120 warning("Duplicated ref: %s", q->name);
121 e = q;
122 q = q->next;
123 qsize--;
124 free(e);
125 e = p;
126 p = p->next;
127 psize--;
131 e->next = NULL;
133 if (l)
134 l->next = e;
135 if (!new_list)
136 new_list = e;
137 l = e;
140 p = q;
143 k = k * 2;
144 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
146 return new_list;
150 * Future: need to be in "struct repository"
151 * when doing a full libification.
153 struct cached_refs {
154 char did_loose;
155 char did_packed;
156 struct ref_list *loose;
157 struct ref_list *packed;
158 } cached_refs;
160 static void free_ref_list(struct ref_list *list)
162 struct ref_list *next;
163 for ( ; list; list = next) {
164 next = list->next;
165 free(list);
169 static void invalidate_cached_refs(void)
171 struct cached_refs *ca = &cached_refs;
173 if (ca->did_loose && ca->loose)
174 free_ref_list(ca->loose);
175 if (ca->did_packed && ca->packed)
176 free_ref_list(ca->packed);
177 ca->loose = ca->packed = NULL;
178 ca->did_loose = ca->did_packed = 0;
181 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
183 struct ref_list *list = NULL;
184 struct ref_list *last = NULL;
185 char refline[PATH_MAX];
186 int flag = REF_ISPACKED;
188 while (fgets(refline, sizeof(refline), f)) {
189 unsigned char sha1[20];
190 const char *name;
191 static const char header[] = "# pack-refs with:";
193 if (!strncmp(refline, header, sizeof(header)-1)) {
194 const char *traits = refline + sizeof(header) - 1;
195 if (strstr(traits, " peeled "))
196 flag |= REF_KNOWS_PEELED;
197 /* perhaps other traits later as well */
198 continue;
201 name = parse_ref_line(refline, sha1);
202 if (name) {
203 list = add_ref(name, sha1, flag, list, &last);
204 continue;
206 if (last &&
207 refline[0] == '^' &&
208 strlen(refline) == 42 &&
209 refline[41] == '\n' &&
210 !get_sha1_hex(refline + 1, sha1))
211 hashcpy(last->peeled, sha1);
213 cached_refs->packed = sort_ref_list(list);
216 static struct ref_list *get_packed_refs(void)
218 if (!cached_refs.did_packed) {
219 FILE *f = fopen(git_path("packed-refs"), "r");
220 cached_refs.packed = NULL;
221 if (f) {
222 read_packed_refs(f, &cached_refs);
223 fclose(f);
225 cached_refs.did_packed = 1;
227 return cached_refs.packed;
230 static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
232 DIR *dir = opendir(git_path("%s", base));
234 if (dir) {
235 struct dirent *de;
236 int baselen = strlen(base);
237 char *ref = xmalloc(baselen + 257);
239 memcpy(ref, base, baselen);
240 if (baselen && base[baselen-1] != '/')
241 ref[baselen++] = '/';
243 while ((de = readdir(dir)) != NULL) {
244 unsigned char sha1[20];
245 struct stat st;
246 int flag;
247 int namelen;
249 if (de->d_name[0] == '.')
250 continue;
251 namelen = strlen(de->d_name);
252 if (namelen > 255)
253 continue;
254 if (has_extension(de->d_name, ".lock"))
255 continue;
256 memcpy(ref + baselen, de->d_name, namelen+1);
257 if (stat(git_path("%s", ref), &st) < 0)
258 continue;
259 if (S_ISDIR(st.st_mode)) {
260 list = get_ref_dir(ref, list);
261 continue;
263 if (!resolve_ref(ref, sha1, 1, &flag)) {
264 error("%s points nowhere!", ref);
265 continue;
267 list = add_ref(ref, sha1, flag, list, NULL);
269 free(ref);
270 closedir(dir);
272 return sort_ref_list(list);
275 static struct ref_list *get_loose_refs(void)
277 if (!cached_refs.did_loose) {
278 cached_refs.loose = get_ref_dir("refs", NULL);
279 cached_refs.did_loose = 1;
281 return cached_refs.loose;
284 /* We allow "recursive" symbolic refs. Only within reason, though */
285 #define MAXDEPTH 5
286 #define MAXREFLEN (1024)
288 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
290 FILE *f;
291 struct cached_refs refs;
292 struct ref_list *ref;
293 int retval;
295 strcpy(name + pathlen, "packed-refs");
296 f = fopen(name, "r");
297 if (!f)
298 return -1;
299 read_packed_refs(f, &refs);
300 fclose(f);
301 ref = refs.packed;
302 retval = -1;
303 while (ref) {
304 if (!strcmp(ref->name, refname)) {
305 retval = 0;
306 memcpy(result, ref->sha1, 20);
307 break;
309 ref = ref->next;
311 free_ref_list(refs.packed);
312 return retval;
315 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
317 int fd, len = strlen(refname);
318 char buffer[128], *p;
320 if (recursion > MAXDEPTH || len > MAXREFLEN)
321 return -1;
322 memcpy(name + pathlen, refname, len+1);
323 fd = open(name, O_RDONLY);
324 if (fd < 0)
325 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
327 len = read(fd, buffer, sizeof(buffer)-1);
328 close(fd);
329 if (len < 0)
330 return -1;
331 while (len && isspace(buffer[len-1]))
332 len--;
333 buffer[len] = 0;
335 /* Was it a detached head or an old-fashioned symlink? */
336 if (!get_sha1_hex(buffer, result))
337 return 0;
339 /* Symref? */
340 if (strncmp(buffer, "ref:", 4))
341 return -1;
342 p = buffer + 4;
343 while (isspace(*p))
344 p++;
346 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
349 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
351 int len = strlen(path), retval;
352 char *gitdir;
354 while (len && path[len-1] == '/')
355 len--;
356 if (!len)
357 return -1;
358 gitdir = xmalloc(len + MAXREFLEN + 8);
359 memcpy(gitdir, path, len);
360 memcpy(gitdir + len, "/.git/", 7);
362 retval = resolve_gitlink_ref_recursive(gitdir, len+6, refname, result, 0);
363 free(gitdir);
364 return retval;
367 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
369 int depth = MAXDEPTH, len;
370 char buffer[256];
371 static char ref_buffer[256];
373 if (flag)
374 *flag = 0;
376 for (;;) {
377 const char *path = git_path("%s", ref);
378 struct stat st;
379 char *buf;
380 int fd;
382 if (--depth < 0)
383 return NULL;
385 /* Special case: non-existing file.
386 * Not having the refs/heads/new-branch is OK
387 * if we are writing into it, so is .git/HEAD
388 * that points at refs/heads/master still to be
389 * born. It is NOT OK if we are resolving for
390 * reading.
392 if (lstat(path, &st) < 0) {
393 struct ref_list *list = get_packed_refs();
394 while (list) {
395 if (!strcmp(ref, list->name)) {
396 hashcpy(sha1, list->sha1);
397 if (flag)
398 *flag |= REF_ISPACKED;
399 return ref;
401 list = list->next;
403 if (reading || errno != ENOENT)
404 return NULL;
405 hashclr(sha1);
406 return ref;
409 /* Follow "normalized" - ie "refs/.." symlinks by hand */
410 if (S_ISLNK(st.st_mode)) {
411 len = readlink(path, buffer, sizeof(buffer)-1);
412 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
413 buffer[len] = 0;
414 strcpy(ref_buffer, buffer);
415 ref = ref_buffer;
416 if (flag)
417 *flag |= REF_ISSYMREF;
418 continue;
422 /* Is it a directory? */
423 if (S_ISDIR(st.st_mode)) {
424 errno = EISDIR;
425 return NULL;
429 * Anything else, just open it and try to use it as
430 * a ref
432 fd = open(path, O_RDONLY);
433 if (fd < 0)
434 return NULL;
435 len = read_in_full(fd, buffer, sizeof(buffer)-1);
436 close(fd);
439 * Is it a symbolic ref?
441 if (len < 4 || memcmp("ref:", buffer, 4))
442 break;
443 buf = buffer + 4;
444 len -= 4;
445 while (len && isspace(*buf))
446 buf++, len--;
447 while (len && isspace(buf[len-1]))
448 len--;
449 buf[len] = 0;
450 memcpy(ref_buffer, buf, len + 1);
451 ref = ref_buffer;
452 if (flag)
453 *flag |= REF_ISSYMREF;
455 if (len < 40 || get_sha1_hex(buffer, sha1))
456 return NULL;
457 return ref;
460 int read_ref(const char *ref, unsigned char *sha1)
462 if (resolve_ref(ref, sha1, 1, NULL))
463 return 0;
464 return -1;
467 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
468 void *cb_data, struct ref_list *entry)
470 if (strncmp(base, entry->name, trim))
471 return 0;
472 if (is_null_sha1(entry->sha1))
473 return 0;
474 if (!has_sha1_file(entry->sha1)) {
475 error("%s does not point to a valid object!", entry->name);
476 return 0;
478 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
481 int peel_ref(const char *ref, unsigned char *sha1)
483 int flag;
484 unsigned char base[20];
485 struct object *o;
487 if (!resolve_ref(ref, base, 1, &flag))
488 return -1;
490 if ((flag & REF_ISPACKED)) {
491 struct ref_list *list = get_packed_refs();
493 while (list) {
494 if (!strcmp(list->name, ref)) {
495 if (list->flag & REF_KNOWS_PEELED) {
496 hashcpy(sha1, list->peeled);
497 return 0;
499 /* older pack-refs did not leave peeled ones */
500 break;
502 list = list->next;
506 /* fallback - callers should not call this for unpacked refs */
507 o = parse_object(base);
508 if (o->type == OBJ_TAG) {
509 o = deref_tag(o, ref, 0);
510 if (o) {
511 hashcpy(sha1, o->sha1);
512 return 0;
515 return -1;
518 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
519 void *cb_data)
521 int retval;
522 struct ref_list *packed = get_packed_refs();
523 struct ref_list *loose = get_loose_refs();
525 while (packed && loose) {
526 struct ref_list *entry;
527 int cmp = strcmp(packed->name, loose->name);
528 if (!cmp) {
529 packed = packed->next;
530 continue;
532 if (cmp > 0) {
533 entry = loose;
534 loose = loose->next;
535 } else {
536 entry = packed;
537 packed = packed->next;
539 retval = do_one_ref(base, fn, trim, cb_data, entry);
540 if (retval)
541 return retval;
544 for (packed = packed ? packed : loose; packed; packed = packed->next) {
545 retval = do_one_ref(base, fn, trim, cb_data, packed);
546 if (retval)
547 return retval;
549 return 0;
552 int head_ref(each_ref_fn fn, void *cb_data)
554 unsigned char sha1[20];
555 int flag;
557 if (resolve_ref("HEAD", sha1, 1, &flag))
558 return fn("HEAD", sha1, flag, cb_data);
559 return 0;
562 int for_each_ref(each_ref_fn fn, void *cb_data)
564 return do_for_each_ref("refs/", fn, 0, cb_data);
567 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
569 return do_for_each_ref("refs/tags/", fn, 10, cb_data);
572 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
574 return do_for_each_ref("refs/heads/", fn, 11, cb_data);
577 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
579 return do_for_each_ref("refs/remotes/", fn, 13, cb_data);
582 /* NEEDSWORK: This is only used by ssh-upload and it should go; the
583 * caller should do resolve_ref or read_ref like everybody else. Or
584 * maybe everybody else should use get_ref_sha1() instead of doing
585 * read_ref().
587 int get_ref_sha1(const char *ref, unsigned char *sha1)
589 if (check_ref_format(ref))
590 return -1;
591 return read_ref(mkpath("refs/%s", ref), sha1);
595 * Make sure "ref" is something reasonable to have under ".git/refs/";
596 * We do not like it if:
598 * - any path component of it begins with ".", or
599 * - it has double dots "..", or
600 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
601 * - it ends with a "/".
604 static inline int bad_ref_char(int ch)
606 return (((unsigned) ch) <= ' ' ||
607 ch == '~' || ch == '^' || ch == ':' ||
608 /* 2.13 Pattern Matching Notation */
609 ch == '?' || ch == '*' || ch == '[');
612 int check_ref_format(const char *ref)
614 int ch, level;
615 const char *cp = ref;
617 level = 0;
618 while (1) {
619 while ((ch = *cp++) == '/')
620 ; /* tolerate duplicated slashes */
621 if (!ch)
622 return -1; /* should not end with slashes */
624 /* we are at the beginning of the path component */
625 if (ch == '.' || bad_ref_char(ch))
626 return -1;
628 /* scan the rest of the path component */
629 while ((ch = *cp++) != 0) {
630 if (bad_ref_char(ch))
631 return -1;
632 if (ch == '/')
633 break;
634 if (ch == '.' && *cp == '.')
635 return -1;
637 level++;
638 if (!ch) {
639 if (level < 2)
640 return -2; /* at least of form "heads/blah" */
641 return 0;
646 static struct ref_lock *verify_lock(struct ref_lock *lock,
647 const unsigned char *old_sha1, int mustexist)
649 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
650 error("Can't verify ref %s", lock->ref_name);
651 unlock_ref(lock);
652 return NULL;
654 if (hashcmp(lock->old_sha1, old_sha1)) {
655 error("Ref %s is at %s but expected %s", lock->ref_name,
656 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
657 unlock_ref(lock);
658 return NULL;
660 return lock;
663 static int remove_empty_dir_recursive(char *path, int len)
665 DIR *dir = opendir(path);
666 struct dirent *e;
667 int ret = 0;
669 if (!dir)
670 return -1;
671 if (path[len-1] != '/')
672 path[len++] = '/';
673 while ((e = readdir(dir)) != NULL) {
674 struct stat st;
675 int namlen;
676 if ((e->d_name[0] == '.') &&
677 ((e->d_name[1] == 0) ||
678 ((e->d_name[1] == '.') && e->d_name[2] == 0)))
679 continue; /* "." and ".." */
681 namlen = strlen(e->d_name);
682 if ((len + namlen < PATH_MAX) &&
683 strcpy(path + len, e->d_name) &&
684 !lstat(path, &st) &&
685 S_ISDIR(st.st_mode) &&
686 !remove_empty_dir_recursive(path, len + namlen))
687 continue; /* happy */
689 /* path too long, stat fails, or non-directory still exists */
690 ret = -1;
691 break;
693 closedir(dir);
694 if (!ret) {
695 path[len] = 0;
696 ret = rmdir(path);
698 return ret;
701 static int remove_empty_directories(char *file)
703 /* we want to create a file but there is a directory there;
704 * if that is an empty directory (or a directory that contains
705 * only empty directories), remove them.
707 char path[PATH_MAX];
708 int len = strlen(file);
710 if (len >= PATH_MAX) /* path too long ;-) */
711 return -1;
712 strcpy(path, file);
713 return remove_empty_dir_recursive(path, len);
716 static int is_refname_available(const char *ref, const char *oldref,
717 struct ref_list *list, int quiet)
719 int namlen = strlen(ref); /* e.g. 'foo/bar' */
720 while (list) {
721 /* list->name could be 'foo' or 'foo/bar/baz' */
722 if (!oldref || strcmp(oldref, list->name)) {
723 int len = strlen(list->name);
724 int cmplen = (namlen < len) ? namlen : len;
725 const char *lead = (namlen < len) ? list->name : ref;
726 if (!strncmp(ref, list->name, cmplen) &&
727 lead[cmplen] == '/') {
728 if (!quiet)
729 error("'%s' exists; cannot create '%s'",
730 list->name, ref);
731 return 0;
734 list = list->next;
736 return 1;
739 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int *flag)
741 char *ref_file;
742 const char *orig_ref = ref;
743 struct ref_lock *lock;
744 struct stat st;
745 int last_errno = 0;
746 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
748 lock = xcalloc(1, sizeof(struct ref_lock));
749 lock->lock_fd = -1;
751 ref = resolve_ref(ref, lock->old_sha1, mustexist, flag);
752 if (!ref && errno == EISDIR) {
753 /* we are trying to lock foo but we used to
754 * have foo/bar which now does not exist;
755 * it is normal for the empty directory 'foo'
756 * to remain.
758 ref_file = git_path("%s", orig_ref);
759 if (remove_empty_directories(ref_file)) {
760 last_errno = errno;
761 error("there are still refs under '%s'", orig_ref);
762 goto error_return;
764 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, flag);
766 if (!ref) {
767 last_errno = errno;
768 error("unable to resolve reference %s: %s",
769 orig_ref, strerror(errno));
770 goto error_return;
772 /* When the ref did not exist and we are creating it,
773 * make sure there is no existing ref that is packed
774 * whose name begins with our refname, nor a ref whose
775 * name is a proper prefix of our refname.
777 if (is_null_sha1(lock->old_sha1) &&
778 !is_refname_available(ref, NULL, get_packed_refs(), 0))
779 goto error_return;
781 lock->lk = xcalloc(1, sizeof(struct lock_file));
783 lock->ref_name = xstrdup(ref);
784 lock->orig_ref_name = xstrdup(orig_ref);
785 ref_file = git_path("%s", ref);
786 lock->force_write = lstat(ref_file, &st) && errno == ENOENT;
788 if (safe_create_leading_directories(ref_file)) {
789 last_errno = errno;
790 error("unable to create directory for %s", ref_file);
791 goto error_return;
793 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, 1);
795 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
797 error_return:
798 unlock_ref(lock);
799 errno = last_errno;
800 return NULL;
803 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
805 char refpath[PATH_MAX];
806 if (check_ref_format(ref))
807 return NULL;
808 strcpy(refpath, mkpath("refs/%s", ref));
809 return lock_ref_sha1_basic(refpath, old_sha1, NULL);
812 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1)
814 if (check_ref_format(ref) == -1)
815 return NULL;
816 return lock_ref_sha1_basic(ref, old_sha1, NULL);
819 static struct lock_file packlock;
821 static int repack_without_ref(const char *refname)
823 struct ref_list *list, *packed_ref_list;
824 int fd;
825 int found = 0;
827 packed_ref_list = get_packed_refs();
828 for (list = packed_ref_list; list; list = list->next) {
829 if (!strcmp(refname, list->name)) {
830 found = 1;
831 break;
834 if (!found)
835 return 0;
836 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
837 if (fd < 0)
838 return error("cannot delete '%s' from packed refs", refname);
840 for (list = packed_ref_list; list; list = list->next) {
841 char line[PATH_MAX + 100];
842 int len;
844 if (!strcmp(refname, list->name))
845 continue;
846 len = snprintf(line, sizeof(line), "%s %s\n",
847 sha1_to_hex(list->sha1), list->name);
848 /* this should not happen but just being defensive */
849 if (len > sizeof(line))
850 die("too long a refname '%s'", list->name);
851 write_or_die(fd, line, len);
853 return commit_lock_file(&packlock);
856 int delete_ref(const char *refname, const unsigned char *sha1)
858 struct ref_lock *lock;
859 int err, i, ret = 0, flag = 0;
861 lock = lock_ref_sha1_basic(refname, sha1, &flag);
862 if (!lock)
863 return 1;
864 if (!(flag & REF_ISPACKED)) {
865 /* loose */
866 i = strlen(lock->lk->filename) - 5; /* .lock */
867 lock->lk->filename[i] = 0;
868 err = unlink(lock->lk->filename);
869 if (err) {
870 ret = 1;
871 error("unlink(%s) failed: %s",
872 lock->lk->filename, strerror(errno));
874 lock->lk->filename[i] = '.';
876 /* removing the loose one could have resurrected an earlier
877 * packed one. Also, if it was not loose we need to repack
878 * without it.
880 ret |= repack_without_ref(refname);
882 err = unlink(git_path("logs/%s", lock->ref_name));
883 if (err && errno != ENOENT)
884 fprintf(stderr, "warning: unlink(%s) failed: %s",
885 git_path("logs/%s", lock->ref_name), strerror(errno));
886 invalidate_cached_refs();
887 unlock_ref(lock);
888 return ret;
891 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
893 static const char renamed_ref[] = "RENAMED-REF";
894 unsigned char sha1[20], orig_sha1[20];
895 int flag = 0, logmoved = 0;
896 struct ref_lock *lock;
897 struct stat loginfo;
898 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
900 if (S_ISLNK(loginfo.st_mode))
901 return error("reflog for %s is a symlink", oldref);
903 if (!resolve_ref(oldref, orig_sha1, 1, &flag))
904 return error("refname %s not found", oldref);
906 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
907 return 1;
909 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
910 return 1;
912 lock = lock_ref_sha1_basic(renamed_ref, NULL, NULL);
913 if (!lock)
914 return error("unable to lock %s", renamed_ref);
915 lock->force_write = 1;
916 if (write_ref_sha1(lock, orig_sha1, logmsg))
917 return error("unable to save current sha1 in %s", renamed_ref);
919 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
920 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
921 oldref, strerror(errno));
923 if (delete_ref(oldref, orig_sha1)) {
924 error("unable to delete old %s", oldref);
925 goto rollback;
928 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1)) {
929 if (errno==EISDIR) {
930 if (remove_empty_directories(git_path("%s", newref))) {
931 error("Directory not empty: %s", newref);
932 goto rollback;
934 } else {
935 error("unable to delete existing %s", newref);
936 goto rollback;
940 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
941 error("unable to create directory for %s", newref);
942 goto rollback;
945 retry:
946 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
947 if (errno==EISDIR || errno==ENOTDIR) {
949 * rename(a, b) when b is an existing
950 * directory ought to result in ISDIR, but
951 * Solaris 5.8 gives ENOTDIR. Sheesh.
953 if (remove_empty_directories(git_path("logs/%s", newref))) {
954 error("Directory not empty: logs/%s", newref);
955 goto rollback;
957 goto retry;
958 } else {
959 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
960 newref, strerror(errno));
961 goto rollback;
964 logmoved = log;
966 lock = lock_ref_sha1_basic(newref, NULL, NULL);
967 if (!lock) {
968 error("unable to lock %s for update", newref);
969 goto rollback;
972 lock->force_write = 1;
973 hashcpy(lock->old_sha1, orig_sha1);
974 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
975 error("unable to write current sha1 into %s", newref);
976 goto rollback;
979 return 0;
981 rollback:
982 lock = lock_ref_sha1_basic(oldref, NULL, NULL);
983 if (!lock) {
984 error("unable to lock %s for rollback", oldref);
985 goto rollbacklog;
988 lock->force_write = 1;
989 flag = log_all_ref_updates;
990 log_all_ref_updates = 0;
991 if (write_ref_sha1(lock, orig_sha1, NULL))
992 error("unable to write current sha1 into %s", oldref);
993 log_all_ref_updates = flag;
995 rollbacklog:
996 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
997 error("unable to restore logfile %s from %s: %s",
998 oldref, newref, strerror(errno));
999 if (!logmoved && log &&
1000 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1001 error("unable to restore logfile %s from tmp-renamed-log: %s",
1002 oldref, strerror(errno));
1004 return 1;
1007 void unlock_ref(struct ref_lock *lock)
1009 if (lock->lock_fd >= 0) {
1010 close(lock->lock_fd);
1011 /* Do not free lock->lk -- atexit() still looks at them */
1012 if (lock->lk)
1013 rollback_lock_file(lock->lk);
1015 free(lock->ref_name);
1016 free(lock->orig_ref_name);
1017 free(lock);
1020 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1021 const unsigned char *new_sha1, const char *msg)
1023 int logfd, written, oflags = O_APPEND | O_WRONLY;
1024 unsigned maxlen, len;
1025 int msglen;
1026 char *log_file, *logrec;
1027 const char *committer;
1029 if (log_all_ref_updates < 0)
1030 log_all_ref_updates = !is_bare_repository();
1032 log_file = git_path("logs/%s", ref_name);
1034 if (log_all_ref_updates &&
1035 (!prefixcmp(ref_name, "refs/heads/") ||
1036 !prefixcmp(ref_name, "refs/remotes/") ||
1037 !strcmp(ref_name, "HEAD"))) {
1038 if (safe_create_leading_directories(log_file) < 0)
1039 return error("unable to create directory for %s",
1040 log_file);
1041 oflags |= O_CREAT;
1044 logfd = open(log_file, oflags, 0666);
1045 if (logfd < 0) {
1046 if (!(oflags & O_CREAT) && errno == ENOENT)
1047 return 0;
1049 if ((oflags & O_CREAT) && errno == EISDIR) {
1050 if (remove_empty_directories(log_file)) {
1051 return error("There are still logs under '%s'",
1052 log_file);
1054 logfd = open(log_file, oflags, 0666);
1057 if (logfd < 0)
1058 return error("Unable to append to %s: %s",
1059 log_file, strerror(errno));
1062 adjust_shared_perm(log_file);
1064 msglen = 0;
1065 if (msg) {
1066 /* clean up the message and make sure it is a single line */
1067 for ( ; *msg; msg++)
1068 if (!isspace(*msg))
1069 break;
1070 if (*msg) {
1071 const char *ep = strchr(msg, '\n');
1072 if (ep)
1073 msglen = ep - msg;
1074 else
1075 msglen = strlen(msg);
1079 committer = git_committer_info(-1);
1080 maxlen = strlen(committer) + msglen + 100;
1081 logrec = xmalloc(maxlen);
1082 len = sprintf(logrec, "%s %s %s\n",
1083 sha1_to_hex(old_sha1),
1084 sha1_to_hex(new_sha1),
1085 committer);
1086 if (msglen)
1087 len += sprintf(logrec + len - 1, "\t%.*s\n", msglen, msg) - 1;
1088 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1089 free(logrec);
1090 close(logfd);
1091 if (written != len)
1092 return error("Unable to append to %s", log_file);
1093 return 0;
1096 int write_ref_sha1(struct ref_lock *lock,
1097 const unsigned char *sha1, const char *logmsg)
1099 static char term = '\n';
1101 if (!lock)
1102 return -1;
1103 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1104 unlock_ref(lock);
1105 return 0;
1107 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1108 write_in_full(lock->lock_fd, &term, 1) != 1
1109 || close(lock->lock_fd) < 0) {
1110 error("Couldn't write %s", lock->lk->filename);
1111 unlock_ref(lock);
1112 return -1;
1114 invalidate_cached_refs();
1115 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1116 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1117 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1118 unlock_ref(lock);
1119 return -1;
1121 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1123 * Special hack: If a branch is updated directly and HEAD
1124 * points to it (may happen on the remote side of a push
1125 * for example) then logically the HEAD reflog should be
1126 * updated too.
1127 * A generic solution implies reverse symref information,
1128 * but finding all symrefs pointing to the given branch
1129 * would be rather costly for this rare event (the direct
1130 * update of a branch) to be worth it. So let's cheat and
1131 * check with HEAD only which should cover 99% of all usage
1132 * scenarios (even 100% of the default ones).
1134 unsigned char head_sha1[20];
1135 int head_flag;
1136 const char *head_ref;
1137 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1138 if (head_ref && (head_flag & REF_ISSYMREF) &&
1139 !strcmp(head_ref, lock->ref_name))
1140 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1142 if (commit_lock_file(lock->lk)) {
1143 error("Couldn't set %s", lock->ref_name);
1144 unlock_ref(lock);
1145 return -1;
1147 lock->lock_fd = -1;
1148 unlock_ref(lock);
1149 return 0;
1152 int create_symref(const char *ref_target, const char *refs_heads_master,
1153 const char *logmsg)
1155 const char *lockpath;
1156 char ref[1000];
1157 int fd, len, written;
1158 char *git_HEAD = xstrdup(git_path("%s", ref_target));
1159 unsigned char old_sha1[20], new_sha1[20];
1161 if (logmsg && read_ref(ref_target, old_sha1))
1162 hashclr(old_sha1);
1164 if (safe_create_leading_directories(git_HEAD) < 0)
1165 return error("unable to create directory for %s", git_HEAD);
1167 #ifndef NO_SYMLINK_HEAD
1168 if (prefer_symlink_refs) {
1169 unlink(git_HEAD);
1170 if (!symlink(refs_heads_master, git_HEAD))
1171 goto done;
1172 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1174 #endif
1176 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1177 if (sizeof(ref) <= len) {
1178 error("refname too long: %s", refs_heads_master);
1179 goto error_free_return;
1181 lockpath = mkpath("%s.lock", git_HEAD);
1182 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1183 if (fd < 0) {
1184 error("Unable to open %s for writing", lockpath);
1185 goto error_free_return;
1187 written = write_in_full(fd, ref, len);
1188 close(fd);
1189 if (written != len) {
1190 error("Unable to write to %s", lockpath);
1191 goto error_unlink_return;
1193 if (rename(lockpath, git_HEAD) < 0) {
1194 error("Unable to create %s", git_HEAD);
1195 goto error_unlink_return;
1197 if (adjust_shared_perm(git_HEAD)) {
1198 error("Unable to fix permissions on %s", lockpath);
1199 error_unlink_return:
1200 unlink(lockpath);
1201 error_free_return:
1202 free(git_HEAD);
1203 return -1;
1206 #ifndef NO_SYMLINK_HEAD
1207 done:
1208 #endif
1209 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1210 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1212 free(git_HEAD);
1213 return 0;
1216 static char *ref_msg(const char *line, const char *endp)
1218 const char *ep;
1219 char *msg;
1221 line += 82;
1222 for (ep = line; ep < endp && *ep != '\n'; ep++)
1224 msg = xmalloc(ep - line + 1);
1225 memcpy(msg, line, ep - line);
1226 msg[ep - line] = 0;
1227 return msg;
1230 int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *sha1, char **msg, unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
1232 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1233 char *tz_c;
1234 int logfd, tz, reccnt = 0;
1235 struct stat st;
1236 unsigned long date;
1237 unsigned char logged_sha1[20];
1238 void *log_mapped;
1239 size_t mapsz;
1241 logfile = git_path("logs/%s", ref);
1242 logfd = open(logfile, O_RDONLY, 0);
1243 if (logfd < 0)
1244 die("Unable to read log %s: %s", logfile, strerror(errno));
1245 fstat(logfd, &st);
1246 if (!st.st_size)
1247 die("Log %s is empty.", logfile);
1248 mapsz = xsize_t(st.st_size);
1249 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1250 logdata = log_mapped;
1251 close(logfd);
1253 lastrec = NULL;
1254 rec = logend = logdata + st.st_size;
1255 while (logdata < rec) {
1256 reccnt++;
1257 if (logdata < rec && *(rec-1) == '\n')
1258 rec--;
1259 lastgt = NULL;
1260 while (logdata < rec && *(rec-1) != '\n') {
1261 rec--;
1262 if (*rec == '>')
1263 lastgt = rec;
1265 if (!lastgt)
1266 die("Log %s is corrupt.", logfile);
1267 date = strtoul(lastgt + 1, &tz_c, 10);
1268 if (date <= at_time || cnt == 0) {
1269 tz = strtoul(tz_c, NULL, 10);
1270 if (msg)
1271 *msg = ref_msg(rec, logend);
1272 if (cutoff_time)
1273 *cutoff_time = date;
1274 if (cutoff_tz)
1275 *cutoff_tz = tz;
1276 if (cutoff_cnt)
1277 *cutoff_cnt = reccnt - 1;
1278 if (lastrec) {
1279 if (get_sha1_hex(lastrec, logged_sha1))
1280 die("Log %s is corrupt.", logfile);
1281 if (get_sha1_hex(rec + 41, sha1))
1282 die("Log %s is corrupt.", logfile);
1283 if (hashcmp(logged_sha1, sha1)) {
1284 fprintf(stderr,
1285 "warning: Log %s has gap after %s.\n",
1286 logfile, show_rfc2822_date(date, tz));
1289 else if (date == at_time) {
1290 if (get_sha1_hex(rec + 41, sha1))
1291 die("Log %s is corrupt.", logfile);
1293 else {
1294 if (get_sha1_hex(rec + 41, logged_sha1))
1295 die("Log %s is corrupt.", logfile);
1296 if (hashcmp(logged_sha1, sha1)) {
1297 fprintf(stderr,
1298 "warning: Log %s unexpectedly ended on %s.\n",
1299 logfile, show_rfc2822_date(date, tz));
1302 munmap(log_mapped, mapsz);
1303 return 0;
1305 lastrec = rec;
1306 if (cnt > 0)
1307 cnt--;
1310 rec = logdata;
1311 while (rec < logend && *rec != '>' && *rec != '\n')
1312 rec++;
1313 if (rec == logend || *rec == '\n')
1314 die("Log %s is corrupt.", logfile);
1315 date = strtoul(rec + 1, &tz_c, 10);
1316 tz = strtoul(tz_c, NULL, 10);
1317 if (get_sha1_hex(logdata, sha1))
1318 die("Log %s is corrupt.", logfile);
1319 if (msg)
1320 *msg = ref_msg(logdata, logend);
1321 munmap(log_mapped, mapsz);
1323 if (cutoff_time)
1324 *cutoff_time = date;
1325 if (cutoff_tz)
1326 *cutoff_tz = tz;
1327 if (cutoff_cnt)
1328 *cutoff_cnt = reccnt;
1329 return 1;
1332 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1334 const char *logfile;
1335 FILE *logfp;
1336 char buf[1024];
1337 int ret = 0;
1339 logfile = git_path("logs/%s", ref);
1340 logfp = fopen(logfile, "r");
1341 if (!logfp)
1342 return -1;
1343 while (fgets(buf, sizeof(buf), logfp)) {
1344 unsigned char osha1[20], nsha1[20];
1345 char *email_end, *message;
1346 unsigned long timestamp;
1347 int len, tz;
1349 /* old SP new SP name <email> SP time TAB msg LF */
1350 len = strlen(buf);
1351 if (len < 83 || buf[len-1] != '\n' ||
1352 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
1353 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1354 !(email_end = strchr(buf + 82, '>')) ||
1355 email_end[1] != ' ' ||
1356 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1357 !message || message[0] != ' ' ||
1358 (message[1] != '+' && message[1] != '-') ||
1359 !isdigit(message[2]) || !isdigit(message[3]) ||
1360 !isdigit(message[4]) || !isdigit(message[5]))
1361 continue; /* corrupt? */
1362 email_end[1] = '\0';
1363 tz = strtol(message + 1, NULL, 10);
1364 if (message[6] != '\t')
1365 message += 6;
1366 else
1367 message += 7;
1368 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1369 if (ret)
1370 break;
1372 fclose(logfp);
1373 return ret;
1376 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1378 DIR *dir = opendir(git_path("logs/%s", base));
1379 int retval = 0;
1381 if (dir) {
1382 struct dirent *de;
1383 int baselen = strlen(base);
1384 char *log = xmalloc(baselen + 257);
1386 memcpy(log, base, baselen);
1387 if (baselen && base[baselen-1] != '/')
1388 log[baselen++] = '/';
1390 while ((de = readdir(dir)) != NULL) {
1391 struct stat st;
1392 int namelen;
1394 if (de->d_name[0] == '.')
1395 continue;
1396 namelen = strlen(de->d_name);
1397 if (namelen > 255)
1398 continue;
1399 if (has_extension(de->d_name, ".lock"))
1400 continue;
1401 memcpy(log + baselen, de->d_name, namelen+1);
1402 if (stat(git_path("logs/%s", log), &st) < 0)
1403 continue;
1404 if (S_ISDIR(st.st_mode)) {
1405 retval = do_for_each_reflog(log, fn, cb_data);
1406 } else {
1407 unsigned char sha1[20];
1408 if (!resolve_ref(log, sha1, 0, NULL))
1409 retval = error("bad ref for %s", log);
1410 else
1411 retval = fn(log, sha1, 0, cb_data);
1413 if (retval)
1414 break;
1416 free(log);
1417 closedir(dir);
1419 else if (*base)
1420 return errno;
1421 return retval;
1424 int for_each_reflog(each_ref_fn fn, void *cb_data)
1426 return do_for_each_reflog("", fn, cb_data);