git-svn: Same default as cvsimport when using --use-log-author
[git/jnareb-git.git] / refs.c
blob4db73ed8f01200fca4008bafb23bda36a8e23446
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
7 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8 #define REF_KNOWS_PEELED 04
10 struct ref_list {
11 struct ref_list *next;
12 unsigned char flag; /* ISSYMREF? ISPACKED? */
13 unsigned char sha1[20];
14 unsigned char peeled[20];
15 char name[FLEX_ARRAY];
18 static const char *parse_ref_line(char *line, unsigned char *sha1)
21 * 42: the answer to everything.
23 * In this case, it happens to be the answer to
24 * 40 (length of sha1 hex representation)
25 * +1 (space in between hex and name)
26 * +1 (newline at the end of the line)
28 int len = strlen(line) - 42;
30 if (len <= 0)
31 return NULL;
32 if (get_sha1_hex(line, sha1) < 0)
33 return NULL;
34 if (!isspace(line[40]))
35 return NULL;
36 line += 41;
37 if (isspace(*line))
38 return NULL;
39 if (line[len] != '\n')
40 return NULL;
41 line[len] = 0;
43 return line;
46 static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
47 int flag, struct ref_list *list,
48 struct ref_list **new_entry)
50 int len;
51 struct ref_list *entry;
53 /* Allocate it and add it in.. */
54 len = strlen(name) + 1;
55 entry = xmalloc(sizeof(struct ref_list) + len);
56 hashcpy(entry->sha1, sha1);
57 hashclr(entry->peeled);
58 memcpy(entry->name, name, len);
59 entry->flag = flag;
60 entry->next = list;
61 if (new_entry)
62 *new_entry = entry;
63 return entry;
66 /* merge sort the ref list */
67 static struct ref_list *sort_ref_list(struct ref_list *list)
69 int psize, qsize, last_merge_count, cmp;
70 struct ref_list *p, *q, *l, *e;
71 struct ref_list *new_list = list;
72 int k = 1;
73 int merge_count = 0;
75 if (!list)
76 return list;
78 do {
79 last_merge_count = merge_count;
80 merge_count = 0;
82 psize = 0;
84 p = new_list;
85 q = new_list;
86 new_list = NULL;
87 l = NULL;
89 while (p) {
90 merge_count++;
92 while (psize < k && q->next) {
93 q = q->next;
94 psize++;
96 qsize = k;
98 while ((psize > 0) || (qsize > 0 && q)) {
99 if (qsize == 0 || !q) {
100 e = p;
101 p = p->next;
102 psize--;
103 } else if (psize == 0) {
104 e = q;
105 q = q->next;
106 qsize--;
107 } else {
108 cmp = strcmp(q->name, p->name);
109 if (cmp < 0) {
110 e = q;
111 q = q->next;
112 qsize--;
113 } else if (cmp > 0) {
114 e = p;
115 p = p->next;
116 psize--;
117 } else {
118 if (hashcmp(q->sha1, p->sha1))
119 die("Duplicated ref, and SHA1s don't match: %s",
120 q->name);
121 warning("Duplicated ref: %s", q->name);
122 e = q;
123 q = q->next;
124 qsize--;
125 free(e);
126 e = p;
127 p = p->next;
128 psize--;
132 e->next = NULL;
134 if (l)
135 l->next = e;
136 if (!new_list)
137 new_list = e;
138 l = e;
141 p = q;
144 k = k * 2;
145 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
147 return new_list;
151 * Future: need to be in "struct repository"
152 * when doing a full libification.
154 static struct cached_refs {
155 char did_loose;
156 char did_packed;
157 struct ref_list *loose;
158 struct ref_list *packed;
159 } cached_refs;
160 static struct ref_list *current_ref;
162 static void free_ref_list(struct ref_list *list)
164 struct ref_list *next;
165 for ( ; list; list = next) {
166 next = list->next;
167 free(list);
171 static void invalidate_cached_refs(void)
173 struct cached_refs *ca = &cached_refs;
175 if (ca->did_loose && ca->loose)
176 free_ref_list(ca->loose);
177 if (ca->did_packed && ca->packed)
178 free_ref_list(ca->packed);
179 ca->loose = ca->packed = NULL;
180 ca->did_loose = ca->did_packed = 0;
183 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
185 struct ref_list *list = NULL;
186 struct ref_list *last = NULL;
187 char refline[PATH_MAX];
188 int flag = REF_ISPACKED;
190 while (fgets(refline, sizeof(refline), f)) {
191 unsigned char sha1[20];
192 const char *name;
193 static const char header[] = "# pack-refs with:";
195 if (!strncmp(refline, header, sizeof(header)-1)) {
196 const char *traits = refline + sizeof(header) - 1;
197 if (strstr(traits, " peeled "))
198 flag |= REF_KNOWS_PEELED;
199 /* perhaps other traits later as well */
200 continue;
203 name = parse_ref_line(refline, sha1);
204 if (name) {
205 list = add_ref(name, sha1, flag, list, &last);
206 continue;
208 if (last &&
209 refline[0] == '^' &&
210 strlen(refline) == 42 &&
211 refline[41] == '\n' &&
212 !get_sha1_hex(refline + 1, sha1))
213 hashcpy(last->peeled, sha1);
215 cached_refs->packed = sort_ref_list(list);
218 static struct ref_list *get_packed_refs(void)
220 if (!cached_refs.did_packed) {
221 FILE *f = fopen(git_path("packed-refs"), "r");
222 cached_refs.packed = NULL;
223 if (f) {
224 read_packed_refs(f, &cached_refs);
225 fclose(f);
227 cached_refs.did_packed = 1;
229 return cached_refs.packed;
232 static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
234 DIR *dir = opendir(git_path("%s", base));
236 if (dir) {
237 struct dirent *de;
238 int baselen = strlen(base);
239 char *ref = xmalloc(baselen + 257);
241 memcpy(ref, base, baselen);
242 if (baselen && base[baselen-1] != '/')
243 ref[baselen++] = '/';
245 while ((de = readdir(dir)) != NULL) {
246 unsigned char sha1[20];
247 struct stat st;
248 int flag;
249 int namelen;
251 if (de->d_name[0] == '.')
252 continue;
253 namelen = strlen(de->d_name);
254 if (namelen > 255)
255 continue;
256 if (has_extension(de->d_name, ".lock"))
257 continue;
258 memcpy(ref + baselen, de->d_name, namelen+1);
259 if (stat(git_path("%s", ref), &st) < 0)
260 continue;
261 if (S_ISDIR(st.st_mode)) {
262 list = get_ref_dir(ref, list);
263 continue;
265 if (!resolve_ref(ref, sha1, 1, &flag)) {
266 error("%s points nowhere!", ref);
267 continue;
269 list = add_ref(ref, sha1, flag, list, NULL);
271 free(ref);
272 closedir(dir);
274 return sort_ref_list(list);
277 static struct ref_list *get_loose_refs(void)
279 if (!cached_refs.did_loose) {
280 cached_refs.loose = get_ref_dir("refs", NULL);
281 cached_refs.did_loose = 1;
283 return cached_refs.loose;
286 /* We allow "recursive" symbolic refs. Only within reason, though */
287 #define MAXDEPTH 5
288 #define MAXREFLEN (1024)
290 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
292 FILE *f;
293 struct cached_refs refs;
294 struct ref_list *ref;
295 int retval;
297 strcpy(name + pathlen, "packed-refs");
298 f = fopen(name, "r");
299 if (!f)
300 return -1;
301 read_packed_refs(f, &refs);
302 fclose(f);
303 ref = refs.packed;
304 retval = -1;
305 while (ref) {
306 if (!strcmp(ref->name, refname)) {
307 retval = 0;
308 memcpy(result, ref->sha1, 20);
309 break;
311 ref = ref->next;
313 free_ref_list(refs.packed);
314 return retval;
317 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
319 int fd, len = strlen(refname);
320 char buffer[128], *p;
322 if (recursion > MAXDEPTH || len > MAXREFLEN)
323 return -1;
324 memcpy(name + pathlen, refname, len+1);
325 fd = open(name, O_RDONLY);
326 if (fd < 0)
327 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
329 len = read(fd, buffer, sizeof(buffer)-1);
330 close(fd);
331 if (len < 0)
332 return -1;
333 while (len && isspace(buffer[len-1]))
334 len--;
335 buffer[len] = 0;
337 /* Was it a detached head or an old-fashioned symlink? */
338 if (!get_sha1_hex(buffer, result))
339 return 0;
341 /* Symref? */
342 if (strncmp(buffer, "ref:", 4))
343 return -1;
344 p = buffer + 4;
345 while (isspace(*p))
346 p++;
348 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
351 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
353 int len = strlen(path), retval;
354 char *gitdir;
356 while (len && path[len-1] == '/')
357 len--;
358 if (!len)
359 return -1;
360 gitdir = xmalloc(len + MAXREFLEN + 8);
361 memcpy(gitdir, path, len);
362 memcpy(gitdir + len, "/.git/", 7);
364 retval = resolve_gitlink_ref_recursive(gitdir, len+6, refname, result, 0);
365 free(gitdir);
366 return retval;
369 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
371 int depth = MAXDEPTH;
372 ssize_t len;
373 char buffer[256];
374 static char ref_buffer[256];
376 if (flag)
377 *flag = 0;
379 for (;;) {
380 const char *path = git_path("%s", ref);
381 struct stat st;
382 char *buf;
383 int fd;
385 if (--depth < 0)
386 return NULL;
388 /* Special case: non-existing file.
389 * Not having the refs/heads/new-branch is OK
390 * if we are writing into it, so is .git/HEAD
391 * that points at refs/heads/master still to be
392 * born. It is NOT OK if we are resolving for
393 * reading.
395 if (lstat(path, &st) < 0) {
396 struct ref_list *list = get_packed_refs();
397 while (list) {
398 if (!strcmp(ref, list->name)) {
399 hashcpy(sha1, list->sha1);
400 if (flag)
401 *flag |= REF_ISPACKED;
402 return ref;
404 list = list->next;
406 if (reading || errno != ENOENT)
407 return NULL;
408 hashclr(sha1);
409 return ref;
412 /* Follow "normalized" - ie "refs/.." symlinks by hand */
413 if (S_ISLNK(st.st_mode)) {
414 len = readlink(path, buffer, sizeof(buffer)-1);
415 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
416 buffer[len] = 0;
417 strcpy(ref_buffer, buffer);
418 ref = ref_buffer;
419 if (flag)
420 *flag |= REF_ISSYMREF;
421 continue;
425 /* Is it a directory? */
426 if (S_ISDIR(st.st_mode)) {
427 errno = EISDIR;
428 return NULL;
432 * Anything else, just open it and try to use it as
433 * a ref
435 fd = open(path, O_RDONLY);
436 if (fd < 0)
437 return NULL;
438 len = read_in_full(fd, buffer, sizeof(buffer)-1);
439 close(fd);
442 * Is it a symbolic ref?
444 if (len < 4 || memcmp("ref:", buffer, 4))
445 break;
446 buf = buffer + 4;
447 len -= 4;
448 while (len && isspace(*buf))
449 buf++, len--;
450 while (len && isspace(buf[len-1]))
451 len--;
452 buf[len] = 0;
453 memcpy(ref_buffer, buf, len + 1);
454 ref = ref_buffer;
455 if (flag)
456 *flag |= REF_ISSYMREF;
458 if (len < 40 || get_sha1_hex(buffer, sha1))
459 return NULL;
460 return ref;
463 int read_ref(const char *ref, unsigned char *sha1)
465 if (resolve_ref(ref, sha1, 1, NULL))
466 return 0;
467 return -1;
470 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
471 void *cb_data, struct ref_list *entry)
473 if (strncmp(base, entry->name, trim))
474 return 0;
475 if (is_null_sha1(entry->sha1))
476 return 0;
477 if (!has_sha1_file(entry->sha1)) {
478 error("%s does not point to a valid object!", entry->name);
479 return 0;
481 current_ref = entry;
482 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
485 int peel_ref(const char *ref, unsigned char *sha1)
487 int flag;
488 unsigned char base[20];
489 struct object *o;
491 if (current_ref && (current_ref->name == ref
492 || !strcmp(current_ref->name, ref))) {
493 if (current_ref->flag & REF_KNOWS_PEELED) {
494 hashcpy(sha1, current_ref->peeled);
495 return 0;
497 hashcpy(base, current_ref->sha1);
498 goto fallback;
501 if (!resolve_ref(ref, base, 1, &flag))
502 return -1;
504 if ((flag & REF_ISPACKED)) {
505 struct ref_list *list = get_packed_refs();
507 while (list) {
508 if (!strcmp(list->name, ref)) {
509 if (list->flag & REF_KNOWS_PEELED) {
510 hashcpy(sha1, list->peeled);
511 return 0;
513 /* older pack-refs did not leave peeled ones */
514 break;
516 list = list->next;
520 fallback:
521 o = parse_object(base);
522 if (o && o->type == OBJ_TAG) {
523 o = deref_tag(o, ref, 0);
524 if (o) {
525 hashcpy(sha1, o->sha1);
526 return 0;
529 return -1;
532 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
533 void *cb_data)
535 int retval = 0;
536 struct ref_list *packed = get_packed_refs();
537 struct ref_list *loose = get_loose_refs();
539 while (packed && loose) {
540 struct ref_list *entry;
541 int cmp = strcmp(packed->name, loose->name);
542 if (!cmp) {
543 packed = packed->next;
544 continue;
546 if (cmp > 0) {
547 entry = loose;
548 loose = loose->next;
549 } else {
550 entry = packed;
551 packed = packed->next;
553 retval = do_one_ref(base, fn, trim, cb_data, entry);
554 if (retval)
555 goto end_each;
558 for (packed = packed ? packed : loose; packed; packed = packed->next) {
559 retval = do_one_ref(base, fn, trim, cb_data, packed);
560 if (retval)
561 goto end_each;
564 end_each:
565 current_ref = NULL;
566 return retval;
569 int head_ref(each_ref_fn fn, void *cb_data)
571 unsigned char sha1[20];
572 int flag;
574 if (resolve_ref("HEAD", sha1, 1, &flag))
575 return fn("HEAD", sha1, flag, cb_data);
576 return 0;
579 int for_each_ref(each_ref_fn fn, void *cb_data)
581 return do_for_each_ref("refs/", fn, 0, cb_data);
584 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
586 return do_for_each_ref("refs/tags/", fn, 10, cb_data);
589 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
591 return do_for_each_ref("refs/heads/", fn, 11, cb_data);
594 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
596 return do_for_each_ref("refs/remotes/", fn, 13, cb_data);
600 * Make sure "ref" is something reasonable to have under ".git/refs/";
601 * We do not like it if:
603 * - any path component of it begins with ".", or
604 * - it has double dots "..", or
605 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
606 * - it ends with a "/".
609 static inline int bad_ref_char(int ch)
611 if (((unsigned) ch) <= ' ' ||
612 ch == '~' || ch == '^' || ch == ':')
613 return 1;
614 /* 2.13 Pattern Matching Notation */
615 if (ch == '?' || ch == '[') /* Unsupported */
616 return 1;
617 if (ch == '*') /* Supported at the end */
618 return 2;
619 return 0;
622 int check_ref_format(const char *ref)
624 int ch, level, bad_type;
625 const char *cp = ref;
627 level = 0;
628 while (1) {
629 while ((ch = *cp++) == '/')
630 ; /* tolerate duplicated slashes */
631 if (!ch)
632 /* should not end with slashes */
633 return CHECK_REF_FORMAT_ERROR;
635 /* we are at the beginning of the path component */
636 if (ch == '.')
637 return CHECK_REF_FORMAT_ERROR;
638 bad_type = bad_ref_char(ch);
639 if (bad_type) {
640 return (bad_type == 2 && !*cp)
641 ? CHECK_REF_FORMAT_WILDCARD
642 : CHECK_REF_FORMAT_ERROR;
645 /* scan the rest of the path component */
646 while ((ch = *cp++) != 0) {
647 bad_type = bad_ref_char(ch);
648 if (bad_type) {
649 return (bad_type == 2 && !*cp)
650 ? CHECK_REF_FORMAT_WILDCARD
651 : CHECK_REF_FORMAT_ERROR;
653 if (ch == '/')
654 break;
655 if (ch == '.' && *cp == '.')
656 return CHECK_REF_FORMAT_ERROR;
658 level++;
659 if (!ch) {
660 if (level < 2)
661 return CHECK_REF_FORMAT_ONELEVEL;
662 return CHECK_REF_FORMAT_OK;
667 const char *ref_rev_parse_rules[] = {
668 "%.*s",
669 "refs/%.*s",
670 "refs/tags/%.*s",
671 "refs/heads/%.*s",
672 "refs/remotes/%.*s",
673 "refs/remotes/%.*s/HEAD",
674 NULL
677 const char *ref_fetch_rules[] = {
678 "%.*s",
679 "refs/%.*s",
680 "refs/heads/%.*s",
681 NULL
684 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
686 const char **p;
687 const int abbrev_name_len = strlen(abbrev_name);
689 for (p = rules; *p; p++) {
690 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
691 return 1;
695 return 0;
698 static struct ref_lock *verify_lock(struct ref_lock *lock,
699 const unsigned char *old_sha1, int mustexist)
701 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
702 error("Can't verify ref %s", lock->ref_name);
703 unlock_ref(lock);
704 return NULL;
706 if (hashcmp(lock->old_sha1, old_sha1)) {
707 error("Ref %s is at %s but expected %s", lock->ref_name,
708 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
709 unlock_ref(lock);
710 return NULL;
712 return lock;
715 static int remove_empty_directories(const char *file)
717 /* we want to create a file but there is a directory there;
718 * if that is an empty directory (or a directory that contains
719 * only empty directories), remove them.
721 struct strbuf path;
722 int result;
724 strbuf_init(&path, 20);
725 strbuf_addstr(&path, file);
727 result = remove_dir_recursively(&path, 1);
729 strbuf_release(&path);
731 return result;
734 static int is_refname_available(const char *ref, const char *oldref,
735 struct ref_list *list, int quiet)
737 int namlen = strlen(ref); /* e.g. 'foo/bar' */
738 while (list) {
739 /* list->name could be 'foo' or 'foo/bar/baz' */
740 if (!oldref || strcmp(oldref, list->name)) {
741 int len = strlen(list->name);
742 int cmplen = (namlen < len) ? namlen : len;
743 const char *lead = (namlen < len) ? list->name : ref;
744 if (!strncmp(ref, list->name, cmplen) &&
745 lead[cmplen] == '/') {
746 if (!quiet)
747 error("'%s' exists; cannot create '%s'",
748 list->name, ref);
749 return 0;
752 list = list->next;
754 return 1;
757 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
759 char *ref_file;
760 const char *orig_ref = ref;
761 struct ref_lock *lock;
762 struct stat st;
763 int last_errno = 0;
764 int type;
765 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
767 lock = xcalloc(1, sizeof(struct ref_lock));
768 lock->lock_fd = -1;
770 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
771 if (!ref && errno == EISDIR) {
772 /* we are trying to lock foo but we used to
773 * have foo/bar which now does not exist;
774 * it is normal for the empty directory 'foo'
775 * to remain.
777 ref_file = git_path("%s", orig_ref);
778 if (remove_empty_directories(ref_file)) {
779 last_errno = errno;
780 error("there are still refs under '%s'", orig_ref);
781 goto error_return;
783 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
785 if (type_p)
786 *type_p = type;
787 if (!ref) {
788 last_errno = errno;
789 error("unable to resolve reference %s: %s",
790 orig_ref, strerror(errno));
791 goto error_return;
793 /* When the ref did not exist and we are creating it,
794 * make sure there is no existing ref that is packed
795 * whose name begins with our refname, nor a ref whose
796 * name is a proper prefix of our refname.
798 if (is_null_sha1(lock->old_sha1) &&
799 !is_refname_available(ref, NULL, get_packed_refs(), 0))
800 goto error_return;
802 lock->lk = xcalloc(1, sizeof(struct lock_file));
804 if (flags & REF_NODEREF)
805 ref = orig_ref;
806 lock->ref_name = xstrdup(ref);
807 lock->orig_ref_name = xstrdup(orig_ref);
808 ref_file = git_path("%s", ref);
809 if (lstat(ref_file, &st) && errno == ENOENT)
810 lock->force_write = 1;
811 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
812 lock->force_write = 1;
814 if (safe_create_leading_directories(ref_file)) {
815 last_errno = errno;
816 error("unable to create directory for %s", ref_file);
817 goto error_return;
819 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, 1);
821 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
823 error_return:
824 unlock_ref(lock);
825 errno = last_errno;
826 return NULL;
829 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
831 char refpath[PATH_MAX];
832 if (check_ref_format(ref))
833 return NULL;
834 strcpy(refpath, mkpath("refs/%s", ref));
835 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
838 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
840 switch (check_ref_format(ref)) {
841 default:
842 return NULL;
843 case 0:
844 case CHECK_REF_FORMAT_ONELEVEL:
845 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
849 static struct lock_file packlock;
851 static int repack_without_ref(const char *refname)
853 struct ref_list *list, *packed_ref_list;
854 int fd;
855 int found = 0;
857 packed_ref_list = get_packed_refs();
858 for (list = packed_ref_list; list; list = list->next) {
859 if (!strcmp(refname, list->name)) {
860 found = 1;
861 break;
864 if (!found)
865 return 0;
866 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
867 if (fd < 0)
868 return error("cannot delete '%s' from packed refs", refname);
870 for (list = packed_ref_list; list; list = list->next) {
871 char line[PATH_MAX + 100];
872 int len;
874 if (!strcmp(refname, list->name))
875 continue;
876 len = snprintf(line, sizeof(line), "%s %s\n",
877 sha1_to_hex(list->sha1), list->name);
878 /* this should not happen but just being defensive */
879 if (len > sizeof(line))
880 die("too long a refname '%s'", list->name);
881 write_or_die(fd, line, len);
883 return commit_lock_file(&packlock);
886 int delete_ref(const char *refname, const unsigned char *sha1)
888 struct ref_lock *lock;
889 int err, i, ret = 0, flag = 0;
891 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
892 if (!lock)
893 return 1;
894 if (!(flag & REF_ISPACKED)) {
895 /* loose */
896 i = strlen(lock->lk->filename) - 5; /* .lock */
897 lock->lk->filename[i] = 0;
898 err = unlink(lock->lk->filename);
899 if (err) {
900 ret = 1;
901 error("unlink(%s) failed: %s",
902 lock->lk->filename, strerror(errno));
904 lock->lk->filename[i] = '.';
906 /* removing the loose one could have resurrected an earlier
907 * packed one. Also, if it was not loose we need to repack
908 * without it.
910 ret |= repack_without_ref(refname);
912 err = unlink(git_path("logs/%s", lock->ref_name));
913 if (err && errno != ENOENT)
914 fprintf(stderr, "warning: unlink(%s) failed: %s",
915 git_path("logs/%s", lock->ref_name), strerror(errno));
916 invalidate_cached_refs();
917 unlock_ref(lock);
918 return ret;
921 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
923 static const char renamed_ref[] = "RENAMED-REF";
924 unsigned char sha1[20], orig_sha1[20];
925 int flag = 0, logmoved = 0;
926 struct ref_lock *lock;
927 struct stat loginfo;
928 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
930 if (S_ISLNK(loginfo.st_mode))
931 return error("reflog for %s is a symlink", oldref);
933 if (!resolve_ref(oldref, orig_sha1, 1, &flag))
934 return error("refname %s not found", oldref);
936 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
937 return 1;
939 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
940 return 1;
942 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
943 if (!lock)
944 return error("unable to lock %s", renamed_ref);
945 lock->force_write = 1;
946 if (write_ref_sha1(lock, orig_sha1, logmsg))
947 return error("unable to save current sha1 in %s", renamed_ref);
949 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
950 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
951 oldref, strerror(errno));
953 if (delete_ref(oldref, orig_sha1)) {
954 error("unable to delete old %s", oldref);
955 goto rollback;
958 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1)) {
959 if (errno==EISDIR) {
960 if (remove_empty_directories(git_path("%s", newref))) {
961 error("Directory not empty: %s", newref);
962 goto rollback;
964 } else {
965 error("unable to delete existing %s", newref);
966 goto rollback;
970 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
971 error("unable to create directory for %s", newref);
972 goto rollback;
975 retry:
976 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
977 if (errno==EISDIR || errno==ENOTDIR) {
979 * rename(a, b) when b is an existing
980 * directory ought to result in ISDIR, but
981 * Solaris 5.8 gives ENOTDIR. Sheesh.
983 if (remove_empty_directories(git_path("logs/%s", newref))) {
984 error("Directory not empty: logs/%s", newref);
985 goto rollback;
987 goto retry;
988 } else {
989 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
990 newref, strerror(errno));
991 goto rollback;
994 logmoved = log;
996 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
997 if (!lock) {
998 error("unable to lock %s for update", newref);
999 goto rollback;
1002 lock->force_write = 1;
1003 hashcpy(lock->old_sha1, orig_sha1);
1004 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1005 error("unable to write current sha1 into %s", newref);
1006 goto rollback;
1009 return 0;
1011 rollback:
1012 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1013 if (!lock) {
1014 error("unable to lock %s for rollback", oldref);
1015 goto rollbacklog;
1018 lock->force_write = 1;
1019 flag = log_all_ref_updates;
1020 log_all_ref_updates = 0;
1021 if (write_ref_sha1(lock, orig_sha1, NULL))
1022 error("unable to write current sha1 into %s", oldref);
1023 log_all_ref_updates = flag;
1025 rollbacklog:
1026 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1027 error("unable to restore logfile %s from %s: %s",
1028 oldref, newref, strerror(errno));
1029 if (!logmoved && log &&
1030 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1031 error("unable to restore logfile %s from tmp-renamed-log: %s",
1032 oldref, strerror(errno));
1034 return 1;
1037 int close_ref(struct ref_lock *lock)
1039 if (close_lock_file(lock->lk))
1040 return -1;
1041 lock->lock_fd = -1;
1042 return 0;
1045 int commit_ref(struct ref_lock *lock)
1047 if (commit_lock_file(lock->lk))
1048 return -1;
1049 lock->lock_fd = -1;
1050 return 0;
1053 void unlock_ref(struct ref_lock *lock)
1055 /* Do not free lock->lk -- atexit() still looks at them */
1056 if (lock->lk)
1057 rollback_lock_file(lock->lk);
1058 free(lock->ref_name);
1059 free(lock->orig_ref_name);
1060 free(lock);
1064 * copy the reflog message msg to buf, which has been allocated sufficiently
1065 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1066 * because reflog file is one line per entry.
1068 static int copy_msg(char *buf, const char *msg)
1070 char *cp = buf;
1071 char c;
1072 int wasspace = 1;
1074 *cp++ = '\t';
1075 while ((c = *msg++)) {
1076 if (wasspace && isspace(c))
1077 continue;
1078 wasspace = isspace(c);
1079 if (wasspace)
1080 c = ' ';
1081 *cp++ = c;
1083 while (buf < cp && isspace(cp[-1]))
1084 cp--;
1085 *cp++ = '\n';
1086 return cp - buf;
1089 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1090 const unsigned char *new_sha1, const char *msg)
1092 int logfd, written, oflags = O_APPEND | O_WRONLY;
1093 unsigned maxlen, len;
1094 int msglen;
1095 char *log_file, *logrec;
1096 const char *committer;
1098 if (log_all_ref_updates < 0)
1099 log_all_ref_updates = !is_bare_repository();
1101 log_file = git_path("logs/%s", ref_name);
1103 if (log_all_ref_updates &&
1104 (!prefixcmp(ref_name, "refs/heads/") ||
1105 !prefixcmp(ref_name, "refs/remotes/") ||
1106 !strcmp(ref_name, "HEAD"))) {
1107 if (safe_create_leading_directories(log_file) < 0)
1108 return error("unable to create directory for %s",
1109 log_file);
1110 oflags |= O_CREAT;
1113 logfd = open(log_file, oflags, 0666);
1114 if (logfd < 0) {
1115 if (!(oflags & O_CREAT) && errno == ENOENT)
1116 return 0;
1118 if ((oflags & O_CREAT) && errno == EISDIR) {
1119 if (remove_empty_directories(log_file)) {
1120 return error("There are still logs under '%s'",
1121 log_file);
1123 logfd = open(log_file, oflags, 0666);
1126 if (logfd < 0)
1127 return error("Unable to append to %s: %s",
1128 log_file, strerror(errno));
1131 adjust_shared_perm(log_file);
1133 msglen = msg ? strlen(msg) : 0;
1134 committer = git_committer_info(0);
1135 maxlen = strlen(committer) + msglen + 100;
1136 logrec = xmalloc(maxlen);
1137 len = sprintf(logrec, "%s %s %s\n",
1138 sha1_to_hex(old_sha1),
1139 sha1_to_hex(new_sha1),
1140 committer);
1141 if (msglen)
1142 len += copy_msg(logrec + len - 1, msg) - 1;
1143 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1144 free(logrec);
1145 if (close(logfd) != 0 || written != len)
1146 return error("Unable to append to %s", log_file);
1147 return 0;
1150 static int is_branch(const char *refname)
1152 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1155 int write_ref_sha1(struct ref_lock *lock,
1156 const unsigned char *sha1, const char *logmsg)
1158 static char term = '\n';
1159 struct object *o;
1161 if (!lock)
1162 return -1;
1163 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1164 unlock_ref(lock);
1165 return 0;
1167 o = parse_object(sha1);
1168 if (!o) {
1169 error("Trying to write ref %s with nonexistant object %s",
1170 lock->ref_name, sha1_to_hex(sha1));
1171 unlock_ref(lock);
1172 return -1;
1174 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1175 error("Trying to write non-commit object %s to branch %s",
1176 sha1_to_hex(sha1), lock->ref_name);
1177 unlock_ref(lock);
1178 return -1;
1180 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1181 write_in_full(lock->lock_fd, &term, 1) != 1
1182 || close_ref(lock) < 0) {
1183 error("Couldn't write %s", lock->lk->filename);
1184 unlock_ref(lock);
1185 return -1;
1187 invalidate_cached_refs();
1188 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1189 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1190 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1191 unlock_ref(lock);
1192 return -1;
1194 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1196 * Special hack: If a branch is updated directly and HEAD
1197 * points to it (may happen on the remote side of a push
1198 * for example) then logically the HEAD reflog should be
1199 * updated too.
1200 * A generic solution implies reverse symref information,
1201 * but finding all symrefs pointing to the given branch
1202 * would be rather costly for this rare event (the direct
1203 * update of a branch) to be worth it. So let's cheat and
1204 * check with HEAD only which should cover 99% of all usage
1205 * scenarios (even 100% of the default ones).
1207 unsigned char head_sha1[20];
1208 int head_flag;
1209 const char *head_ref;
1210 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1211 if (head_ref && (head_flag & REF_ISSYMREF) &&
1212 !strcmp(head_ref, lock->ref_name))
1213 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1215 if (commit_ref(lock)) {
1216 error("Couldn't set %s", lock->ref_name);
1217 unlock_ref(lock);
1218 return -1;
1220 unlock_ref(lock);
1221 return 0;
1224 int create_symref(const char *ref_target, const char *refs_heads_master,
1225 const char *logmsg)
1227 const char *lockpath;
1228 char ref[1000];
1229 int fd, len, written;
1230 char *git_HEAD = xstrdup(git_path("%s", ref_target));
1231 unsigned char old_sha1[20], new_sha1[20];
1233 if (logmsg && read_ref(ref_target, old_sha1))
1234 hashclr(old_sha1);
1236 if (safe_create_leading_directories(git_HEAD) < 0)
1237 return error("unable to create directory for %s", git_HEAD);
1239 #ifndef NO_SYMLINK_HEAD
1240 if (prefer_symlink_refs) {
1241 unlink(git_HEAD);
1242 if (!symlink(refs_heads_master, git_HEAD))
1243 goto done;
1244 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1246 #endif
1248 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1249 if (sizeof(ref) <= len) {
1250 error("refname too long: %s", refs_heads_master);
1251 goto error_free_return;
1253 lockpath = mkpath("%s.lock", git_HEAD);
1254 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1255 if (fd < 0) {
1256 error("Unable to open %s for writing", lockpath);
1257 goto error_free_return;
1259 written = write_in_full(fd, ref, len);
1260 if (close(fd) != 0 || written != len) {
1261 error("Unable to write to %s", lockpath);
1262 goto error_unlink_return;
1264 if (rename(lockpath, git_HEAD) < 0) {
1265 error("Unable to create %s", git_HEAD);
1266 goto error_unlink_return;
1268 if (adjust_shared_perm(git_HEAD)) {
1269 error("Unable to fix permissions on %s", lockpath);
1270 error_unlink_return:
1271 unlink(lockpath);
1272 error_free_return:
1273 free(git_HEAD);
1274 return -1;
1277 #ifndef NO_SYMLINK_HEAD
1278 done:
1279 #endif
1280 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1281 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1283 free(git_HEAD);
1284 return 0;
1287 static char *ref_msg(const char *line, const char *endp)
1289 const char *ep;
1290 line += 82;
1291 ep = memchr(line, '\n', endp - line);
1292 if (!ep)
1293 ep = endp;
1294 return xmemdupz(line, ep - line);
1297 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)
1299 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1300 char *tz_c;
1301 int logfd, tz, reccnt = 0;
1302 struct stat st;
1303 unsigned long date;
1304 unsigned char logged_sha1[20];
1305 void *log_mapped;
1306 size_t mapsz;
1308 logfile = git_path("logs/%s", ref);
1309 logfd = open(logfile, O_RDONLY, 0);
1310 if (logfd < 0)
1311 die("Unable to read log %s: %s", logfile, strerror(errno));
1312 fstat(logfd, &st);
1313 if (!st.st_size)
1314 die("Log %s is empty.", logfile);
1315 mapsz = xsize_t(st.st_size);
1316 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1317 logdata = log_mapped;
1318 close(logfd);
1320 lastrec = NULL;
1321 rec = logend = logdata + st.st_size;
1322 while (logdata < rec) {
1323 reccnt++;
1324 if (logdata < rec && *(rec-1) == '\n')
1325 rec--;
1326 lastgt = NULL;
1327 while (logdata < rec && *(rec-1) != '\n') {
1328 rec--;
1329 if (*rec == '>')
1330 lastgt = rec;
1332 if (!lastgt)
1333 die("Log %s is corrupt.", logfile);
1334 date = strtoul(lastgt + 1, &tz_c, 10);
1335 if (date <= at_time || cnt == 0) {
1336 tz = strtoul(tz_c, NULL, 10);
1337 if (msg)
1338 *msg = ref_msg(rec, logend);
1339 if (cutoff_time)
1340 *cutoff_time = date;
1341 if (cutoff_tz)
1342 *cutoff_tz = tz;
1343 if (cutoff_cnt)
1344 *cutoff_cnt = reccnt - 1;
1345 if (lastrec) {
1346 if (get_sha1_hex(lastrec, logged_sha1))
1347 die("Log %s is corrupt.", logfile);
1348 if (get_sha1_hex(rec + 41, sha1))
1349 die("Log %s is corrupt.", logfile);
1350 if (hashcmp(logged_sha1, sha1)) {
1351 fprintf(stderr,
1352 "warning: Log %s has gap after %s.\n",
1353 logfile, show_date(date, tz, DATE_RFC2822));
1356 else if (date == at_time) {
1357 if (get_sha1_hex(rec + 41, sha1))
1358 die("Log %s is corrupt.", logfile);
1360 else {
1361 if (get_sha1_hex(rec + 41, logged_sha1))
1362 die("Log %s is corrupt.", logfile);
1363 if (hashcmp(logged_sha1, sha1)) {
1364 fprintf(stderr,
1365 "warning: Log %s unexpectedly ended on %s.\n",
1366 logfile, show_date(date, tz, DATE_RFC2822));
1369 munmap(log_mapped, mapsz);
1370 return 0;
1372 lastrec = rec;
1373 if (cnt > 0)
1374 cnt--;
1377 rec = logdata;
1378 while (rec < logend && *rec != '>' && *rec != '\n')
1379 rec++;
1380 if (rec == logend || *rec == '\n')
1381 die("Log %s is corrupt.", logfile);
1382 date = strtoul(rec + 1, &tz_c, 10);
1383 tz = strtoul(tz_c, NULL, 10);
1384 if (get_sha1_hex(logdata, sha1))
1385 die("Log %s is corrupt.", logfile);
1386 if (msg)
1387 *msg = ref_msg(logdata, logend);
1388 munmap(log_mapped, mapsz);
1390 if (cutoff_time)
1391 *cutoff_time = date;
1392 if (cutoff_tz)
1393 *cutoff_tz = tz;
1394 if (cutoff_cnt)
1395 *cutoff_cnt = reccnt;
1396 return 1;
1399 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1401 const char *logfile;
1402 FILE *logfp;
1403 char buf[1024];
1404 int ret = 0;
1406 logfile = git_path("logs/%s", ref);
1407 logfp = fopen(logfile, "r");
1408 if (!logfp)
1409 return -1;
1410 while (fgets(buf, sizeof(buf), logfp)) {
1411 unsigned char osha1[20], nsha1[20];
1412 char *email_end, *message;
1413 unsigned long timestamp;
1414 int len, tz;
1416 /* old SP new SP name <email> SP time TAB msg LF */
1417 len = strlen(buf);
1418 if (len < 83 || buf[len-1] != '\n' ||
1419 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
1420 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1421 !(email_end = strchr(buf + 82, '>')) ||
1422 email_end[1] != ' ' ||
1423 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1424 !message || message[0] != ' ' ||
1425 (message[1] != '+' && message[1] != '-') ||
1426 !isdigit(message[2]) || !isdigit(message[3]) ||
1427 !isdigit(message[4]) || !isdigit(message[5]))
1428 continue; /* corrupt? */
1429 email_end[1] = '\0';
1430 tz = strtol(message + 1, NULL, 10);
1431 if (message[6] != '\t')
1432 message += 6;
1433 else
1434 message += 7;
1435 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1436 if (ret)
1437 break;
1439 fclose(logfp);
1440 return ret;
1443 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1445 DIR *dir = opendir(git_path("logs/%s", base));
1446 int retval = 0;
1448 if (dir) {
1449 struct dirent *de;
1450 int baselen = strlen(base);
1451 char *log = xmalloc(baselen + 257);
1453 memcpy(log, base, baselen);
1454 if (baselen && base[baselen-1] != '/')
1455 log[baselen++] = '/';
1457 while ((de = readdir(dir)) != NULL) {
1458 struct stat st;
1459 int namelen;
1461 if (de->d_name[0] == '.')
1462 continue;
1463 namelen = strlen(de->d_name);
1464 if (namelen > 255)
1465 continue;
1466 if (has_extension(de->d_name, ".lock"))
1467 continue;
1468 memcpy(log + baselen, de->d_name, namelen+1);
1469 if (stat(git_path("logs/%s", log), &st) < 0)
1470 continue;
1471 if (S_ISDIR(st.st_mode)) {
1472 retval = do_for_each_reflog(log, fn, cb_data);
1473 } else {
1474 unsigned char sha1[20];
1475 if (!resolve_ref(log, sha1, 0, NULL))
1476 retval = error("bad ref for %s", log);
1477 else
1478 retval = fn(log, sha1, 0, cb_data);
1480 if (retval)
1481 break;
1483 free(log);
1484 closedir(dir);
1486 else if (*base)
1487 return errno;
1488 return retval;
1491 int for_each_reflog(each_ref_fn fn, void *cb_data)
1493 return do_for_each_reflog("", fn, cb_data);
1496 int update_ref(const char *action, const char *refname,
1497 const unsigned char *sha1, const unsigned char *oldval,
1498 int flags, enum action_on_err onerr)
1500 static struct ref_lock *lock;
1501 lock = lock_any_ref_for_update(refname, oldval, flags);
1502 if (!lock) {
1503 const char *str = "Cannot lock the ref '%s'.";
1504 switch (onerr) {
1505 case MSG_ON_ERR: error(str, refname); break;
1506 case DIE_ON_ERR: die(str, refname); break;
1507 case QUIET_ON_ERR: break;
1509 return 1;
1511 if (write_ref_sha1(lock, sha1, action) < 0) {
1512 const char *str = "Cannot update the ref '%s'.";
1513 switch (onerr) {
1514 case MSG_ON_ERR: error(str, refname); break;
1515 case DIE_ON_ERR: die(str, refname); break;
1516 case QUIET_ON_ERR: break;
1518 return 1;
1520 return 0;
1523 struct ref *find_ref_by_name(struct ref *list, const char *name)
1525 for ( ; list; list = list->next)
1526 if (!strcmp(list->name, name))
1527 return list;
1528 return NULL;