Merge branch 'maint'
[alt-git.git] / refs.c
blobd3db15a76cc46f6f6a31d4448816c09e6c48e543
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
9 #define REF_BROKEN 010
11 struct ref_list {
12 struct ref_list *next;
13 unsigned char flag; /* ISSYMREF? ISPACKED? */
14 unsigned char sha1[20];
15 unsigned char peeled[20];
16 char name[FLEX_ARRAY];
19 static const char *parse_ref_line(char *line, unsigned char *sha1)
22 * 42: the answer to everything.
24 * In this case, it happens to be the answer to
25 * 40 (length of sha1 hex representation)
26 * +1 (space in between hex and name)
27 * +1 (newline at the end of the line)
29 int len = strlen(line) - 42;
31 if (len <= 0)
32 return NULL;
33 if (get_sha1_hex(line, sha1) < 0)
34 return NULL;
35 if (!isspace(line[40]))
36 return NULL;
37 line += 41;
38 if (isspace(*line))
39 return NULL;
40 if (line[len] != '\n')
41 return NULL;
42 line[len] = 0;
44 return line;
47 static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
48 int flag, struct ref_list *list,
49 struct ref_list **new_entry)
51 int len;
52 struct ref_list *entry;
54 /* Allocate it and add it in.. */
55 len = strlen(name) + 1;
56 entry = xmalloc(sizeof(struct ref_list) + len);
57 hashcpy(entry->sha1, sha1);
58 hashclr(entry->peeled);
59 memcpy(entry->name, name, len);
60 entry->flag = flag;
61 entry->next = list;
62 if (new_entry)
63 *new_entry = entry;
64 return entry;
67 /* merge sort the ref list */
68 static struct ref_list *sort_ref_list(struct ref_list *list)
70 int psize, qsize, last_merge_count, cmp;
71 struct ref_list *p, *q, *l, *e;
72 struct ref_list *new_list = list;
73 int k = 1;
74 int merge_count = 0;
76 if (!list)
77 return list;
79 do {
80 last_merge_count = merge_count;
81 merge_count = 0;
83 psize = 0;
85 p = new_list;
86 q = new_list;
87 new_list = NULL;
88 l = NULL;
90 while (p) {
91 merge_count++;
93 while (psize < k && q->next) {
94 q = q->next;
95 psize++;
97 qsize = k;
99 while ((psize > 0) || (qsize > 0 && q)) {
100 if (qsize == 0 || !q) {
101 e = p;
102 p = p->next;
103 psize--;
104 } else if (psize == 0) {
105 e = q;
106 q = q->next;
107 qsize--;
108 } else {
109 cmp = strcmp(q->name, p->name);
110 if (cmp < 0) {
111 e = q;
112 q = q->next;
113 qsize--;
114 } else if (cmp > 0) {
115 e = p;
116 p = p->next;
117 psize--;
118 } else {
119 if (hashcmp(q->sha1, p->sha1))
120 die("Duplicated ref, and SHA1s don't match: %s",
121 q->name);
122 warning("Duplicated ref: %s", q->name);
123 e = q;
124 q = q->next;
125 qsize--;
126 free(e);
127 e = p;
128 p = p->next;
129 psize--;
133 e->next = NULL;
135 if (l)
136 l->next = e;
137 if (!new_list)
138 new_list = e;
139 l = e;
142 p = q;
145 k = k * 2;
146 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
148 return new_list;
152 * Future: need to be in "struct repository"
153 * when doing a full libification.
155 static struct cached_refs {
156 char did_loose;
157 char did_packed;
158 struct ref_list *loose;
159 struct ref_list *packed;
160 } cached_refs;
161 static struct ref_list *current_ref;
163 static struct ref_list *extra_refs;
165 static void free_ref_list(struct ref_list *list)
167 struct ref_list *next;
168 for ( ; list; list = next) {
169 next = list->next;
170 free(list);
174 static void invalidate_cached_refs(void)
176 struct cached_refs *ca = &cached_refs;
178 if (ca->did_loose && ca->loose)
179 free_ref_list(ca->loose);
180 if (ca->did_packed && ca->packed)
181 free_ref_list(ca->packed);
182 ca->loose = ca->packed = NULL;
183 ca->did_loose = ca->did_packed = 0;
186 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
188 struct ref_list *list = NULL;
189 struct ref_list *last = NULL;
190 char refline[PATH_MAX];
191 int flag = REF_ISPACKED;
193 while (fgets(refline, sizeof(refline), f)) {
194 unsigned char sha1[20];
195 const char *name;
196 static const char header[] = "# pack-refs with:";
198 if (!strncmp(refline, header, sizeof(header)-1)) {
199 const char *traits = refline + sizeof(header) - 1;
200 if (strstr(traits, " peeled "))
201 flag |= REF_KNOWS_PEELED;
202 /* perhaps other traits later as well */
203 continue;
206 name = parse_ref_line(refline, sha1);
207 if (name) {
208 list = add_ref(name, sha1, flag, list, &last);
209 continue;
211 if (last &&
212 refline[0] == '^' &&
213 strlen(refline) == 42 &&
214 refline[41] == '\n' &&
215 !get_sha1_hex(refline + 1, sha1))
216 hashcpy(last->peeled, sha1);
218 cached_refs->packed = sort_ref_list(list);
221 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
223 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
226 void clear_extra_refs(void)
228 free_ref_list(extra_refs);
229 extra_refs = NULL;
232 static struct ref_list *get_packed_refs(void)
234 if (!cached_refs.did_packed) {
235 FILE *f = fopen(git_path("packed-refs"), "r");
236 cached_refs.packed = NULL;
237 if (f) {
238 read_packed_refs(f, &cached_refs);
239 fclose(f);
241 cached_refs.did_packed = 1;
243 return cached_refs.packed;
246 static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
248 DIR *dir = opendir(git_path("%s", base));
250 if (dir) {
251 struct dirent *de;
252 int baselen = strlen(base);
253 char *ref = xmalloc(baselen + 257);
255 memcpy(ref, base, baselen);
256 if (baselen && base[baselen-1] != '/')
257 ref[baselen++] = '/';
259 while ((de = readdir(dir)) != NULL) {
260 unsigned char sha1[20];
261 struct stat st;
262 int flag;
263 int namelen;
265 if (de->d_name[0] == '.')
266 continue;
267 namelen = strlen(de->d_name);
268 if (namelen > 255)
269 continue;
270 if (has_extension(de->d_name, ".lock"))
271 continue;
272 memcpy(ref + baselen, de->d_name, namelen+1);
273 if (stat(git_path("%s", ref), &st) < 0)
274 continue;
275 if (S_ISDIR(st.st_mode)) {
276 list = get_ref_dir(ref, list);
277 continue;
279 if (!resolve_ref(ref, sha1, 1, &flag)) {
280 hashclr(sha1);
281 flag |= REF_BROKEN;
283 list = add_ref(ref, sha1, flag, list, NULL);
285 free(ref);
286 closedir(dir);
288 return sort_ref_list(list);
291 struct warn_if_dangling_data {
292 FILE *fp;
293 const char *refname;
294 const char *msg_fmt;
297 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
298 int flags, void *cb_data)
300 struct warn_if_dangling_data *d = cb_data;
301 const char *resolves_to;
302 unsigned char junk[20];
304 if (!(flags & REF_ISSYMREF))
305 return 0;
307 resolves_to = resolve_ref(refname, junk, 0, NULL);
308 if (!resolves_to || strcmp(resolves_to, d->refname))
309 return 0;
311 fprintf(d->fp, d->msg_fmt, refname);
312 return 0;
315 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
317 struct warn_if_dangling_data data = { fp, refname, msg_fmt };
318 for_each_rawref(warn_if_dangling_symref, &data);
321 static struct ref_list *get_loose_refs(void)
323 if (!cached_refs.did_loose) {
324 cached_refs.loose = get_ref_dir("refs", NULL);
325 cached_refs.did_loose = 1;
327 return cached_refs.loose;
330 /* We allow "recursive" symbolic refs. Only within reason, though */
331 #define MAXDEPTH 5
332 #define MAXREFLEN (1024)
334 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
336 FILE *f;
337 struct cached_refs refs;
338 struct ref_list *ref;
339 int retval;
341 strcpy(name + pathlen, "packed-refs");
342 f = fopen(name, "r");
343 if (!f)
344 return -1;
345 read_packed_refs(f, &refs);
346 fclose(f);
347 ref = refs.packed;
348 retval = -1;
349 while (ref) {
350 if (!strcmp(ref->name, refname)) {
351 retval = 0;
352 memcpy(result, ref->sha1, 20);
353 break;
355 ref = ref->next;
357 free_ref_list(refs.packed);
358 return retval;
361 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
363 int fd, len = strlen(refname);
364 char buffer[128], *p;
366 if (recursion > MAXDEPTH || len > MAXREFLEN)
367 return -1;
368 memcpy(name + pathlen, refname, len+1);
369 fd = open(name, O_RDONLY);
370 if (fd < 0)
371 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
373 len = read(fd, buffer, sizeof(buffer)-1);
374 close(fd);
375 if (len < 0)
376 return -1;
377 while (len && isspace(buffer[len-1]))
378 len--;
379 buffer[len] = 0;
381 /* Was it a detached head or an old-fashioned symlink? */
382 if (!get_sha1_hex(buffer, result))
383 return 0;
385 /* Symref? */
386 if (strncmp(buffer, "ref:", 4))
387 return -1;
388 p = buffer + 4;
389 while (isspace(*p))
390 p++;
392 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
395 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
397 int len = strlen(path), retval;
398 char *gitdir;
399 const char *tmp;
401 while (len && path[len-1] == '/')
402 len--;
403 if (!len)
404 return -1;
405 gitdir = xmalloc(len + MAXREFLEN + 8);
406 memcpy(gitdir, path, len);
407 memcpy(gitdir + len, "/.git", 6);
408 len += 5;
410 tmp = read_gitfile_gently(gitdir);
411 if (tmp) {
412 free(gitdir);
413 len = strlen(tmp);
414 gitdir = xmalloc(len + MAXREFLEN + 3);
415 memcpy(gitdir, tmp, len);
417 gitdir[len] = '/';
418 gitdir[++len] = '\0';
419 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
420 free(gitdir);
421 return retval;
425 * If the "reading" argument is set, this function finds out what _object_
426 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
427 * has to exist, and if it is symbolic, it has to point at an existing ref,
428 * because the "read" goes through the symref to the ref it points at.
430 * The access that is not "reading" may often be "writing", but does not
431 * have to; it can be merely checking _where it leads to_. If it is a
432 * prelude to "writing" to the ref, a write to a symref that points at
433 * yet-to-be-born ref will create the real ref pointed by the symref.
434 * reading=0 allows the caller to check where such a symref leads to.
436 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
438 int depth = MAXDEPTH;
439 ssize_t len;
440 char buffer[256];
441 static char ref_buffer[256];
443 if (flag)
444 *flag = 0;
446 for (;;) {
447 char path[PATH_MAX];
448 struct stat st;
449 char *buf;
450 int fd;
452 if (--depth < 0)
453 return NULL;
455 git_snpath(path, sizeof(path), "%s", ref);
456 /* Special case: non-existing file. */
457 if (lstat(path, &st) < 0) {
458 struct ref_list *list = get_packed_refs();
459 while (list) {
460 if (!strcmp(ref, list->name)) {
461 hashcpy(sha1, list->sha1);
462 if (flag)
463 *flag |= REF_ISPACKED;
464 return ref;
466 list = list->next;
468 if (reading || errno != ENOENT)
469 return NULL;
470 hashclr(sha1);
471 return ref;
474 /* Follow "normalized" - ie "refs/.." symlinks by hand */
475 if (S_ISLNK(st.st_mode)) {
476 len = readlink(path, buffer, sizeof(buffer)-1);
477 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
478 buffer[len] = 0;
479 strcpy(ref_buffer, buffer);
480 ref = ref_buffer;
481 if (flag)
482 *flag |= REF_ISSYMREF;
483 continue;
487 /* Is it a directory? */
488 if (S_ISDIR(st.st_mode)) {
489 errno = EISDIR;
490 return NULL;
494 * Anything else, just open it and try to use it as
495 * a ref
497 fd = open(path, O_RDONLY);
498 if (fd < 0)
499 return NULL;
500 len = read_in_full(fd, buffer, sizeof(buffer)-1);
501 close(fd);
504 * Is it a symbolic ref?
506 if (len < 4 || memcmp("ref:", buffer, 4))
507 break;
508 buf = buffer + 4;
509 len -= 4;
510 while (len && isspace(*buf))
511 buf++, len--;
512 while (len && isspace(buf[len-1]))
513 len--;
514 buf[len] = 0;
515 memcpy(ref_buffer, buf, len + 1);
516 ref = ref_buffer;
517 if (flag)
518 *flag |= REF_ISSYMREF;
520 if (len < 40 || get_sha1_hex(buffer, sha1))
521 return NULL;
522 return ref;
525 /* The argument to filter_refs */
526 struct ref_filter {
527 const char *pattern;
528 each_ref_fn *fn;
529 void *cb_data;
532 int read_ref(const char *ref, unsigned char *sha1)
534 if (resolve_ref(ref, sha1, 1, NULL))
535 return 0;
536 return -1;
539 #define DO_FOR_EACH_INCLUDE_BROKEN 01
540 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
541 int flags, void *cb_data, struct ref_list *entry)
543 if (strncmp(base, entry->name, trim))
544 return 0;
546 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
547 if (entry->flag & REF_BROKEN)
548 return 0; /* ignore dangling symref */
549 if (!has_sha1_file(entry->sha1)) {
550 error("%s does not point to a valid object!", entry->name);
551 return 0;
554 current_ref = entry;
555 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
558 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
559 void *data)
561 struct ref_filter *filter = (struct ref_filter *)data;
562 if (fnmatch(filter->pattern, ref, 0))
563 return 0;
564 return filter->fn(ref, sha, flags, filter->cb_data);
567 int peel_ref(const char *ref, unsigned char *sha1)
569 int flag;
570 unsigned char base[20];
571 struct object *o;
573 if (current_ref && (current_ref->name == ref
574 || !strcmp(current_ref->name, ref))) {
575 if (current_ref->flag & REF_KNOWS_PEELED) {
576 hashcpy(sha1, current_ref->peeled);
577 return 0;
579 hashcpy(base, current_ref->sha1);
580 goto fallback;
583 if (!resolve_ref(ref, base, 1, &flag))
584 return -1;
586 if ((flag & REF_ISPACKED)) {
587 struct ref_list *list = get_packed_refs();
589 while (list) {
590 if (!strcmp(list->name, ref)) {
591 if (list->flag & REF_KNOWS_PEELED) {
592 hashcpy(sha1, list->peeled);
593 return 0;
595 /* older pack-refs did not leave peeled ones */
596 break;
598 list = list->next;
602 fallback:
603 o = parse_object(base);
604 if (o && o->type == OBJ_TAG) {
605 o = deref_tag(o, ref, 0);
606 if (o) {
607 hashcpy(sha1, o->sha1);
608 return 0;
611 return -1;
614 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
615 int flags, void *cb_data)
617 int retval = 0;
618 struct ref_list *packed = get_packed_refs();
619 struct ref_list *loose = get_loose_refs();
621 struct ref_list *extra;
623 for (extra = extra_refs; extra; extra = extra->next)
624 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
626 while (packed && loose) {
627 struct ref_list *entry;
628 int cmp = strcmp(packed->name, loose->name);
629 if (!cmp) {
630 packed = packed->next;
631 continue;
633 if (cmp > 0) {
634 entry = loose;
635 loose = loose->next;
636 } else {
637 entry = packed;
638 packed = packed->next;
640 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
641 if (retval)
642 goto end_each;
645 for (packed = packed ? packed : loose; packed; packed = packed->next) {
646 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
647 if (retval)
648 goto end_each;
651 end_each:
652 current_ref = NULL;
653 return retval;
656 int head_ref(each_ref_fn fn, void *cb_data)
658 unsigned char sha1[20];
659 int flag;
661 if (resolve_ref("HEAD", sha1, 1, &flag))
662 return fn("HEAD", sha1, flag, cb_data);
663 return 0;
666 int for_each_ref(each_ref_fn fn, void *cb_data)
668 return do_for_each_ref("refs/", fn, 0, 0, cb_data);
671 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
673 return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
676 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
678 return for_each_ref_in("refs/tags/", fn, cb_data);
681 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
683 return for_each_ref_in("refs/heads/", fn, cb_data);
686 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
688 return for_each_ref_in("refs/remotes/", fn, cb_data);
691 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
693 return do_for_each_ref("refs/replace/", fn, 13, 0, cb_data);
696 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
697 const char *prefix, void *cb_data)
699 struct strbuf real_pattern = STRBUF_INIT;
700 struct ref_filter filter;
701 int ret;
703 if (!prefix && prefixcmp(pattern, "refs/"))
704 strbuf_addstr(&real_pattern, "refs/");
705 else if (prefix)
706 strbuf_addstr(&real_pattern, prefix);
707 strbuf_addstr(&real_pattern, pattern);
709 if (!has_glob_specials(pattern)) {
710 /* Append implied '/' '*' if not present. */
711 if (real_pattern.buf[real_pattern.len - 1] != '/')
712 strbuf_addch(&real_pattern, '/');
713 /* No need to check for '*', there is none. */
714 strbuf_addch(&real_pattern, '*');
717 filter.pattern = real_pattern.buf;
718 filter.fn = fn;
719 filter.cb_data = cb_data;
720 ret = for_each_ref(filter_refs, &filter);
722 strbuf_release(&real_pattern);
723 return ret;
726 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
728 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
731 int for_each_rawref(each_ref_fn fn, void *cb_data)
733 return do_for_each_ref("refs/", fn, 0,
734 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
738 * Make sure "ref" is something reasonable to have under ".git/refs/";
739 * We do not like it if:
741 * - any path component of it begins with ".", or
742 * - it has double dots "..", or
743 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
744 * - it ends with a "/".
745 * - it ends with ".lock"
746 * - it contains a "\" (backslash)
749 static inline int bad_ref_char(int ch)
751 if (((unsigned) ch) <= ' ' ||
752 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
753 return 1;
754 /* 2.13 Pattern Matching Notation */
755 if (ch == '?' || ch == '[') /* Unsupported */
756 return 1;
757 if (ch == '*') /* Supported at the end */
758 return 2;
759 return 0;
762 int check_ref_format(const char *ref)
764 int ch, level, bad_type, last;
765 int ret = CHECK_REF_FORMAT_OK;
766 const char *cp = ref;
768 level = 0;
769 while (1) {
770 while ((ch = *cp++) == '/')
771 ; /* tolerate duplicated slashes */
772 if (!ch)
773 /* should not end with slashes */
774 return CHECK_REF_FORMAT_ERROR;
776 /* we are at the beginning of the path component */
777 if (ch == '.')
778 return CHECK_REF_FORMAT_ERROR;
779 bad_type = bad_ref_char(ch);
780 if (bad_type) {
781 if (bad_type == 2 && (!*cp || *cp == '/') &&
782 ret == CHECK_REF_FORMAT_OK)
783 ret = CHECK_REF_FORMAT_WILDCARD;
784 else
785 return CHECK_REF_FORMAT_ERROR;
788 last = ch;
789 /* scan the rest of the path component */
790 while ((ch = *cp++) != 0) {
791 bad_type = bad_ref_char(ch);
792 if (bad_type)
793 return CHECK_REF_FORMAT_ERROR;
794 if (ch == '/')
795 break;
796 if (last == '.' && ch == '.')
797 return CHECK_REF_FORMAT_ERROR;
798 if (last == '@' && ch == '{')
799 return CHECK_REF_FORMAT_ERROR;
800 last = ch;
802 level++;
803 if (!ch) {
804 if (ref <= cp - 2 && cp[-2] == '.')
805 return CHECK_REF_FORMAT_ERROR;
806 if (level < 2)
807 return CHECK_REF_FORMAT_ONELEVEL;
808 if (has_extension(ref, ".lock"))
809 return CHECK_REF_FORMAT_ERROR;
810 return ret;
815 const char *prettify_refname(const char *name)
817 return name + (
818 !prefixcmp(name, "refs/heads/") ? 11 :
819 !prefixcmp(name, "refs/tags/") ? 10 :
820 !prefixcmp(name, "refs/remotes/") ? 13 :
824 const char *ref_rev_parse_rules[] = {
825 "%.*s",
826 "refs/%.*s",
827 "refs/tags/%.*s",
828 "refs/heads/%.*s",
829 "refs/remotes/%.*s",
830 "refs/remotes/%.*s/HEAD",
831 NULL
834 const char *ref_fetch_rules[] = {
835 "%.*s",
836 "refs/%.*s",
837 "refs/heads/%.*s",
838 NULL
841 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
843 const char **p;
844 const int abbrev_name_len = strlen(abbrev_name);
846 for (p = rules; *p; p++) {
847 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
848 return 1;
852 return 0;
855 static struct ref_lock *verify_lock(struct ref_lock *lock,
856 const unsigned char *old_sha1, int mustexist)
858 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
859 error("Can't verify ref %s", lock->ref_name);
860 unlock_ref(lock);
861 return NULL;
863 if (hashcmp(lock->old_sha1, old_sha1)) {
864 error("Ref %s is at %s but expected %s", lock->ref_name,
865 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
866 unlock_ref(lock);
867 return NULL;
869 return lock;
872 static int remove_empty_directories(const char *file)
874 /* we want to create a file but there is a directory there;
875 * if that is an empty directory (or a directory that contains
876 * only empty directories), remove them.
878 struct strbuf path;
879 int result;
881 strbuf_init(&path, 20);
882 strbuf_addstr(&path, file);
884 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
886 strbuf_release(&path);
888 return result;
891 static int is_refname_available(const char *ref, const char *oldref,
892 struct ref_list *list, int quiet)
894 int namlen = strlen(ref); /* e.g. 'foo/bar' */
895 while (list) {
896 /* list->name could be 'foo' or 'foo/bar/baz' */
897 if (!oldref || strcmp(oldref, list->name)) {
898 int len = strlen(list->name);
899 int cmplen = (namlen < len) ? namlen : len;
900 const char *lead = (namlen < len) ? list->name : ref;
901 if (!strncmp(ref, list->name, cmplen) &&
902 lead[cmplen] == '/') {
903 if (!quiet)
904 error("'%s' exists; cannot create '%s'",
905 list->name, ref);
906 return 0;
909 list = list->next;
911 return 1;
914 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
916 char *ref_file;
917 const char *orig_ref = ref;
918 struct ref_lock *lock;
919 int last_errno = 0;
920 int type, lflags;
921 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
922 int missing = 0;
924 lock = xcalloc(1, sizeof(struct ref_lock));
925 lock->lock_fd = -1;
927 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
928 if (!ref && errno == EISDIR) {
929 /* we are trying to lock foo but we used to
930 * have foo/bar which now does not exist;
931 * it is normal for the empty directory 'foo'
932 * to remain.
934 ref_file = git_path("%s", orig_ref);
935 if (remove_empty_directories(ref_file)) {
936 last_errno = errno;
937 error("there are still refs under '%s'", orig_ref);
938 goto error_return;
940 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
942 if (type_p)
943 *type_p = type;
944 if (!ref) {
945 last_errno = errno;
946 error("unable to resolve reference %s: %s",
947 orig_ref, strerror(errno));
948 goto error_return;
950 missing = is_null_sha1(lock->old_sha1);
951 /* When the ref did not exist and we are creating it,
952 * make sure there is no existing ref that is packed
953 * whose name begins with our refname, nor a ref whose
954 * name is a proper prefix of our refname.
956 if (missing &&
957 !is_refname_available(ref, NULL, get_packed_refs(), 0)) {
958 last_errno = ENOTDIR;
959 goto error_return;
962 lock->lk = xcalloc(1, sizeof(struct lock_file));
964 lflags = LOCK_DIE_ON_ERROR;
965 if (flags & REF_NODEREF) {
966 ref = orig_ref;
967 lflags |= LOCK_NODEREF;
969 lock->ref_name = xstrdup(ref);
970 lock->orig_ref_name = xstrdup(orig_ref);
971 ref_file = git_path("%s", ref);
972 if (missing)
973 lock->force_write = 1;
974 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
975 lock->force_write = 1;
977 if (safe_create_leading_directories(ref_file)) {
978 last_errno = errno;
979 error("unable to create directory for %s", ref_file);
980 goto error_return;
983 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
984 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
986 error_return:
987 unlock_ref(lock);
988 errno = last_errno;
989 return NULL;
992 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
994 char refpath[PATH_MAX];
995 if (check_ref_format(ref))
996 return NULL;
997 strcpy(refpath, mkpath("refs/%s", ref));
998 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1001 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1003 switch (check_ref_format(ref)) {
1004 default:
1005 return NULL;
1006 case 0:
1007 case CHECK_REF_FORMAT_ONELEVEL:
1008 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1012 static struct lock_file packlock;
1014 static int repack_without_ref(const char *refname)
1016 struct ref_list *list, *packed_ref_list;
1017 int fd;
1018 int found = 0;
1020 packed_ref_list = get_packed_refs();
1021 for (list = packed_ref_list; list; list = list->next) {
1022 if (!strcmp(refname, list->name)) {
1023 found = 1;
1024 break;
1027 if (!found)
1028 return 0;
1029 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1030 if (fd < 0) {
1031 unable_to_lock_error(git_path("packed-refs"), errno);
1032 return error("cannot delete '%s' from packed refs", refname);
1035 for (list = packed_ref_list; list; list = list->next) {
1036 char line[PATH_MAX + 100];
1037 int len;
1039 if (!strcmp(refname, list->name))
1040 continue;
1041 len = snprintf(line, sizeof(line), "%s %s\n",
1042 sha1_to_hex(list->sha1), list->name);
1043 /* this should not happen but just being defensive */
1044 if (len > sizeof(line))
1045 die("too long a refname '%s'", list->name);
1046 write_or_die(fd, line, len);
1048 return commit_lock_file(&packlock);
1051 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1053 struct ref_lock *lock;
1054 int err, i = 0, ret = 0, flag = 0;
1056 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1057 if (!lock)
1058 return 1;
1059 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1060 /* loose */
1061 const char *path;
1063 if (!(delopt & REF_NODEREF)) {
1064 i = strlen(lock->lk->filename) - 5; /* .lock */
1065 lock->lk->filename[i] = 0;
1066 path = lock->lk->filename;
1067 } else {
1068 path = git_path("%s", refname);
1070 err = unlink_or_warn(path);
1071 if (err && errno != ENOENT)
1072 ret = 1;
1074 if (!(delopt & REF_NODEREF))
1075 lock->lk->filename[i] = '.';
1077 /* removing the loose one could have resurrected an earlier
1078 * packed one. Also, if it was not loose we need to repack
1079 * without it.
1081 ret |= repack_without_ref(refname);
1083 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1084 invalidate_cached_refs();
1085 unlock_ref(lock);
1086 return ret;
1089 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1091 static const char renamed_ref[] = "RENAMED-REF";
1092 unsigned char sha1[20], orig_sha1[20];
1093 int flag = 0, logmoved = 0;
1094 struct ref_lock *lock;
1095 struct stat loginfo;
1096 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1097 const char *symref = NULL;
1099 if (log && S_ISLNK(loginfo.st_mode))
1100 return error("reflog for %s is a symlink", oldref);
1102 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1103 if (flag & REF_ISSYMREF)
1104 return error("refname %s is a symbolic ref, renaming it is not supported",
1105 oldref);
1106 if (!symref)
1107 return error("refname %s not found", oldref);
1109 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1110 return 1;
1112 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1113 return 1;
1115 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1116 if (!lock)
1117 return error("unable to lock %s", renamed_ref);
1118 lock->force_write = 1;
1119 if (write_ref_sha1(lock, orig_sha1, logmsg))
1120 return error("unable to save current sha1 in %s", renamed_ref);
1122 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1123 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1124 oldref, strerror(errno));
1126 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1127 error("unable to delete old %s", oldref);
1128 goto rollback;
1131 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1132 if (errno==EISDIR) {
1133 if (remove_empty_directories(git_path("%s", newref))) {
1134 error("Directory not empty: %s", newref);
1135 goto rollback;
1137 } else {
1138 error("unable to delete existing %s", newref);
1139 goto rollback;
1143 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1144 error("unable to create directory for %s", newref);
1145 goto rollback;
1148 retry:
1149 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
1150 if (errno==EISDIR || errno==ENOTDIR) {
1152 * rename(a, b) when b is an existing
1153 * directory ought to result in ISDIR, but
1154 * Solaris 5.8 gives ENOTDIR. Sheesh.
1156 if (remove_empty_directories(git_path("logs/%s", newref))) {
1157 error("Directory not empty: logs/%s", newref);
1158 goto rollback;
1160 goto retry;
1161 } else {
1162 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1163 newref, strerror(errno));
1164 goto rollback;
1167 logmoved = log;
1169 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1170 if (!lock) {
1171 error("unable to lock %s for update", newref);
1172 goto rollback;
1174 lock->force_write = 1;
1175 hashcpy(lock->old_sha1, orig_sha1);
1176 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1177 error("unable to write current sha1 into %s", newref);
1178 goto rollback;
1181 return 0;
1183 rollback:
1184 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1185 if (!lock) {
1186 error("unable to lock %s for rollback", oldref);
1187 goto rollbacklog;
1190 lock->force_write = 1;
1191 flag = log_all_ref_updates;
1192 log_all_ref_updates = 0;
1193 if (write_ref_sha1(lock, orig_sha1, NULL))
1194 error("unable to write current sha1 into %s", oldref);
1195 log_all_ref_updates = flag;
1197 rollbacklog:
1198 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1199 error("unable to restore logfile %s from %s: %s",
1200 oldref, newref, strerror(errno));
1201 if (!logmoved && log &&
1202 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1203 error("unable to restore logfile %s from tmp-renamed-log: %s",
1204 oldref, strerror(errno));
1206 return 1;
1209 int close_ref(struct ref_lock *lock)
1211 if (close_lock_file(lock->lk))
1212 return -1;
1213 lock->lock_fd = -1;
1214 return 0;
1217 int commit_ref(struct ref_lock *lock)
1219 if (commit_lock_file(lock->lk))
1220 return -1;
1221 lock->lock_fd = -1;
1222 return 0;
1225 void unlock_ref(struct ref_lock *lock)
1227 /* Do not free lock->lk -- atexit() still looks at them */
1228 if (lock->lk)
1229 rollback_lock_file(lock->lk);
1230 free(lock->ref_name);
1231 free(lock->orig_ref_name);
1232 free(lock);
1236 * copy the reflog message msg to buf, which has been allocated sufficiently
1237 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1238 * because reflog file is one line per entry.
1240 static int copy_msg(char *buf, const char *msg)
1242 char *cp = buf;
1243 char c;
1244 int wasspace = 1;
1246 *cp++ = '\t';
1247 while ((c = *msg++)) {
1248 if (wasspace && isspace(c))
1249 continue;
1250 wasspace = isspace(c);
1251 if (wasspace)
1252 c = ' ';
1253 *cp++ = c;
1255 while (buf < cp && isspace(cp[-1]))
1256 cp--;
1257 *cp++ = '\n';
1258 return cp - buf;
1261 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1262 const unsigned char *new_sha1, const char *msg)
1264 int logfd, written, oflags = O_APPEND | O_WRONLY;
1265 unsigned maxlen, len;
1266 int msglen;
1267 char log_file[PATH_MAX];
1268 char *logrec;
1269 const char *committer;
1271 if (log_all_ref_updates < 0)
1272 log_all_ref_updates = !is_bare_repository();
1274 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
1276 if (log_all_ref_updates &&
1277 (!prefixcmp(ref_name, "refs/heads/") ||
1278 !prefixcmp(ref_name, "refs/remotes/") ||
1279 !prefixcmp(ref_name, "refs/notes/") ||
1280 !strcmp(ref_name, "HEAD"))) {
1281 if (safe_create_leading_directories(log_file) < 0)
1282 return error("unable to create directory for %s",
1283 log_file);
1284 oflags |= O_CREAT;
1287 logfd = open(log_file, oflags, 0666);
1288 if (logfd < 0) {
1289 if (!(oflags & O_CREAT) && errno == ENOENT)
1290 return 0;
1292 if ((oflags & O_CREAT) && errno == EISDIR) {
1293 if (remove_empty_directories(log_file)) {
1294 return error("There are still logs under '%s'",
1295 log_file);
1297 logfd = open(log_file, oflags, 0666);
1300 if (logfd < 0)
1301 return error("Unable to append to %s: %s",
1302 log_file, strerror(errno));
1305 adjust_shared_perm(log_file);
1307 msglen = msg ? strlen(msg) : 0;
1308 committer = git_committer_info(0);
1309 maxlen = strlen(committer) + msglen + 100;
1310 logrec = xmalloc(maxlen);
1311 len = sprintf(logrec, "%s %s %s\n",
1312 sha1_to_hex(old_sha1),
1313 sha1_to_hex(new_sha1),
1314 committer);
1315 if (msglen)
1316 len += copy_msg(logrec + len - 1, msg) - 1;
1317 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1318 free(logrec);
1319 if (close(logfd) != 0 || written != len)
1320 return error("Unable to append to %s", log_file);
1321 return 0;
1324 static int is_branch(const char *refname)
1326 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1329 int write_ref_sha1(struct ref_lock *lock,
1330 const unsigned char *sha1, const char *logmsg)
1332 static char term = '\n';
1333 struct object *o;
1335 if (!lock)
1336 return -1;
1337 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1338 unlock_ref(lock);
1339 return 0;
1341 o = parse_object(sha1);
1342 if (!o) {
1343 error("Trying to write ref %s with nonexistant object %s",
1344 lock->ref_name, sha1_to_hex(sha1));
1345 unlock_ref(lock);
1346 return -1;
1348 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1349 error("Trying to write non-commit object %s to branch %s",
1350 sha1_to_hex(sha1), lock->ref_name);
1351 unlock_ref(lock);
1352 return -1;
1354 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1355 write_in_full(lock->lock_fd, &term, 1) != 1
1356 || close_ref(lock) < 0) {
1357 error("Couldn't write %s", lock->lk->filename);
1358 unlock_ref(lock);
1359 return -1;
1361 invalidate_cached_refs();
1362 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1363 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1364 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1365 unlock_ref(lock);
1366 return -1;
1368 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1370 * Special hack: If a branch is updated directly and HEAD
1371 * points to it (may happen on the remote side of a push
1372 * for example) then logically the HEAD reflog should be
1373 * updated too.
1374 * A generic solution implies reverse symref information,
1375 * but finding all symrefs pointing to the given branch
1376 * would be rather costly for this rare event (the direct
1377 * update of a branch) to be worth it. So let's cheat and
1378 * check with HEAD only which should cover 99% of all usage
1379 * scenarios (even 100% of the default ones).
1381 unsigned char head_sha1[20];
1382 int head_flag;
1383 const char *head_ref;
1384 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1385 if (head_ref && (head_flag & REF_ISSYMREF) &&
1386 !strcmp(head_ref, lock->ref_name))
1387 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1389 if (commit_ref(lock)) {
1390 error("Couldn't set %s", lock->ref_name);
1391 unlock_ref(lock);
1392 return -1;
1394 unlock_ref(lock);
1395 return 0;
1398 int create_symref(const char *ref_target, const char *refs_heads_master,
1399 const char *logmsg)
1401 const char *lockpath;
1402 char ref[1000];
1403 int fd, len, written;
1404 char *git_HEAD = git_pathdup("%s", ref_target);
1405 unsigned char old_sha1[20], new_sha1[20];
1407 if (logmsg && read_ref(ref_target, old_sha1))
1408 hashclr(old_sha1);
1410 if (safe_create_leading_directories(git_HEAD) < 0)
1411 return error("unable to create directory for %s", git_HEAD);
1413 #ifndef NO_SYMLINK_HEAD
1414 if (prefer_symlink_refs) {
1415 unlink(git_HEAD);
1416 if (!symlink(refs_heads_master, git_HEAD))
1417 goto done;
1418 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1420 #endif
1422 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1423 if (sizeof(ref) <= len) {
1424 error("refname too long: %s", refs_heads_master);
1425 goto error_free_return;
1427 lockpath = mkpath("%s.lock", git_HEAD);
1428 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1429 if (fd < 0) {
1430 error("Unable to open %s for writing", lockpath);
1431 goto error_free_return;
1433 written = write_in_full(fd, ref, len);
1434 if (close(fd) != 0 || written != len) {
1435 error("Unable to write to %s", lockpath);
1436 goto error_unlink_return;
1438 if (rename(lockpath, git_HEAD) < 0) {
1439 error("Unable to create %s", git_HEAD);
1440 goto error_unlink_return;
1442 if (adjust_shared_perm(git_HEAD)) {
1443 error("Unable to fix permissions on %s", lockpath);
1444 error_unlink_return:
1445 unlink_or_warn(lockpath);
1446 error_free_return:
1447 free(git_HEAD);
1448 return -1;
1451 #ifndef NO_SYMLINK_HEAD
1452 done:
1453 #endif
1454 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1455 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1457 free(git_HEAD);
1458 return 0;
1461 static char *ref_msg(const char *line, const char *endp)
1463 const char *ep;
1464 line += 82;
1465 ep = memchr(line, '\n', endp - line);
1466 if (!ep)
1467 ep = endp;
1468 return xmemdupz(line, ep - line);
1471 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)
1473 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1474 char *tz_c;
1475 int logfd, tz, reccnt = 0;
1476 struct stat st;
1477 unsigned long date;
1478 unsigned char logged_sha1[20];
1479 void *log_mapped;
1480 size_t mapsz;
1482 logfile = git_path("logs/%s", ref);
1483 logfd = open(logfile, O_RDONLY, 0);
1484 if (logfd < 0)
1485 die_errno("Unable to read log '%s'", logfile);
1486 fstat(logfd, &st);
1487 if (!st.st_size)
1488 die("Log %s is empty.", logfile);
1489 mapsz = xsize_t(st.st_size);
1490 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1491 logdata = log_mapped;
1492 close(logfd);
1494 lastrec = NULL;
1495 rec = logend = logdata + st.st_size;
1496 while (logdata < rec) {
1497 reccnt++;
1498 if (logdata < rec && *(rec-1) == '\n')
1499 rec--;
1500 lastgt = NULL;
1501 while (logdata < rec && *(rec-1) != '\n') {
1502 rec--;
1503 if (*rec == '>')
1504 lastgt = rec;
1506 if (!lastgt)
1507 die("Log %s is corrupt.", logfile);
1508 date = strtoul(lastgt + 1, &tz_c, 10);
1509 if (date <= at_time || cnt == 0) {
1510 tz = strtoul(tz_c, NULL, 10);
1511 if (msg)
1512 *msg = ref_msg(rec, logend);
1513 if (cutoff_time)
1514 *cutoff_time = date;
1515 if (cutoff_tz)
1516 *cutoff_tz = tz;
1517 if (cutoff_cnt)
1518 *cutoff_cnt = reccnt - 1;
1519 if (lastrec) {
1520 if (get_sha1_hex(lastrec, logged_sha1))
1521 die("Log %s is corrupt.", logfile);
1522 if (get_sha1_hex(rec + 41, sha1))
1523 die("Log %s is corrupt.", logfile);
1524 if (hashcmp(logged_sha1, sha1)) {
1525 warning("Log %s has gap after %s.",
1526 logfile, show_date(date, tz, DATE_RFC2822));
1529 else if (date == at_time) {
1530 if (get_sha1_hex(rec + 41, sha1))
1531 die("Log %s is corrupt.", logfile);
1533 else {
1534 if (get_sha1_hex(rec + 41, logged_sha1))
1535 die("Log %s is corrupt.", logfile);
1536 if (hashcmp(logged_sha1, sha1)) {
1537 warning("Log %s unexpectedly ended on %s.",
1538 logfile, show_date(date, tz, DATE_RFC2822));
1541 munmap(log_mapped, mapsz);
1542 return 0;
1544 lastrec = rec;
1545 if (cnt > 0)
1546 cnt--;
1549 rec = logdata;
1550 while (rec < logend && *rec != '>' && *rec != '\n')
1551 rec++;
1552 if (rec == logend || *rec == '\n')
1553 die("Log %s is corrupt.", logfile);
1554 date = strtoul(rec + 1, &tz_c, 10);
1555 tz = strtoul(tz_c, NULL, 10);
1556 if (get_sha1_hex(logdata, sha1))
1557 die("Log %s is corrupt.", logfile);
1558 if (is_null_sha1(sha1)) {
1559 if (get_sha1_hex(logdata + 41, sha1))
1560 die("Log %s is corrupt.", logfile);
1562 if (msg)
1563 *msg = ref_msg(logdata, logend);
1564 munmap(log_mapped, mapsz);
1566 if (cutoff_time)
1567 *cutoff_time = date;
1568 if (cutoff_tz)
1569 *cutoff_tz = tz;
1570 if (cutoff_cnt)
1571 *cutoff_cnt = reccnt;
1572 return 1;
1575 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1577 const char *logfile;
1578 FILE *logfp;
1579 struct strbuf sb = STRBUF_INIT;
1580 int ret = 0;
1582 logfile = git_path("logs/%s", ref);
1583 logfp = fopen(logfile, "r");
1584 if (!logfp)
1585 return -1;
1587 if (ofs) {
1588 struct stat statbuf;
1589 if (fstat(fileno(logfp), &statbuf) ||
1590 statbuf.st_size < ofs ||
1591 fseek(logfp, -ofs, SEEK_END) ||
1592 strbuf_getwholeline(&sb, logfp, '\n')) {
1593 fclose(logfp);
1594 strbuf_release(&sb);
1595 return -1;
1599 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1600 unsigned char osha1[20], nsha1[20];
1601 char *email_end, *message;
1602 unsigned long timestamp;
1603 int tz;
1605 /* old SP new SP name <email> SP time TAB msg LF */
1606 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1607 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1608 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1609 !(email_end = strchr(sb.buf + 82, '>')) ||
1610 email_end[1] != ' ' ||
1611 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1612 !message || message[0] != ' ' ||
1613 (message[1] != '+' && message[1] != '-') ||
1614 !isdigit(message[2]) || !isdigit(message[3]) ||
1615 !isdigit(message[4]) || !isdigit(message[5]))
1616 continue; /* corrupt? */
1617 email_end[1] = '\0';
1618 tz = strtol(message + 1, NULL, 10);
1619 if (message[6] != '\t')
1620 message += 6;
1621 else
1622 message += 7;
1623 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1624 cb_data);
1625 if (ret)
1626 break;
1628 fclose(logfp);
1629 strbuf_release(&sb);
1630 return ret;
1633 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1635 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1638 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1640 DIR *dir = opendir(git_path("logs/%s", base));
1641 int retval = 0;
1643 if (dir) {
1644 struct dirent *de;
1645 int baselen = strlen(base);
1646 char *log = xmalloc(baselen + 257);
1648 memcpy(log, base, baselen);
1649 if (baselen && base[baselen-1] != '/')
1650 log[baselen++] = '/';
1652 while ((de = readdir(dir)) != NULL) {
1653 struct stat st;
1654 int namelen;
1656 if (de->d_name[0] == '.')
1657 continue;
1658 namelen = strlen(de->d_name);
1659 if (namelen > 255)
1660 continue;
1661 if (has_extension(de->d_name, ".lock"))
1662 continue;
1663 memcpy(log + baselen, de->d_name, namelen+1);
1664 if (stat(git_path("logs/%s", log), &st) < 0)
1665 continue;
1666 if (S_ISDIR(st.st_mode)) {
1667 retval = do_for_each_reflog(log, fn, cb_data);
1668 } else {
1669 unsigned char sha1[20];
1670 if (!resolve_ref(log, sha1, 0, NULL))
1671 retval = error("bad ref for %s", log);
1672 else
1673 retval = fn(log, sha1, 0, cb_data);
1675 if (retval)
1676 break;
1678 free(log);
1679 closedir(dir);
1681 else if (*base)
1682 return errno;
1683 return retval;
1686 int for_each_reflog(each_ref_fn fn, void *cb_data)
1688 return do_for_each_reflog("", fn, cb_data);
1691 int update_ref(const char *action, const char *refname,
1692 const unsigned char *sha1, const unsigned char *oldval,
1693 int flags, enum action_on_err onerr)
1695 static struct ref_lock *lock;
1696 lock = lock_any_ref_for_update(refname, oldval, flags);
1697 if (!lock) {
1698 const char *str = "Cannot lock the ref '%s'.";
1699 switch (onerr) {
1700 case MSG_ON_ERR: error(str, refname); break;
1701 case DIE_ON_ERR: die(str, refname); break;
1702 case QUIET_ON_ERR: break;
1704 return 1;
1706 if (write_ref_sha1(lock, sha1, action) < 0) {
1707 const char *str = "Cannot update the ref '%s'.";
1708 switch (onerr) {
1709 case MSG_ON_ERR: error(str, refname); break;
1710 case DIE_ON_ERR: die(str, refname); break;
1711 case QUIET_ON_ERR: break;
1713 return 1;
1715 return 0;
1718 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1720 for ( ; list; list = list->next)
1721 if (!strcmp(list->name, name))
1722 return (struct ref *)list;
1723 return NULL;
1727 * generate a format suitable for scanf from a ref_rev_parse_rules
1728 * rule, that is replace the "%.*s" spec with a "%s" spec
1730 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1732 char *spec;
1734 spec = strstr(rule, "%.*s");
1735 if (!spec || strstr(spec + 4, "%.*s"))
1736 die("invalid rule in ref_rev_parse_rules: %s", rule);
1738 /* copy all until spec */
1739 strncpy(scanf_fmt, rule, spec - rule);
1740 scanf_fmt[spec - rule] = '\0';
1741 /* copy new spec */
1742 strcat(scanf_fmt, "%s");
1743 /* copy remaining rule */
1744 strcat(scanf_fmt, spec + 4);
1746 return;
1749 char *shorten_unambiguous_ref(const char *ref, int strict)
1751 int i;
1752 static char **scanf_fmts;
1753 static int nr_rules;
1754 char *short_name;
1756 /* pre generate scanf formats from ref_rev_parse_rules[] */
1757 if (!nr_rules) {
1758 size_t total_len = 0;
1760 /* the rule list is NULL terminated, count them first */
1761 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1762 /* no +1 because strlen("%s") < strlen("%.*s") */
1763 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1765 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1767 total_len = 0;
1768 for (i = 0; i < nr_rules; i++) {
1769 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1770 + total_len;
1771 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1772 total_len += strlen(ref_rev_parse_rules[i]);
1776 /* bail out if there are no rules */
1777 if (!nr_rules)
1778 return xstrdup(ref);
1780 /* buffer for scanf result, at most ref must fit */
1781 short_name = xstrdup(ref);
1783 /* skip first rule, it will always match */
1784 for (i = nr_rules - 1; i > 0 ; --i) {
1785 int j;
1786 int rules_to_fail = i;
1787 int short_name_len;
1789 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1790 continue;
1792 short_name_len = strlen(short_name);
1795 * in strict mode, all (except the matched one) rules
1796 * must fail to resolve to a valid non-ambiguous ref
1798 if (strict)
1799 rules_to_fail = nr_rules;
1802 * check if the short name resolves to a valid ref,
1803 * but use only rules prior to the matched one
1805 for (j = 0; j < rules_to_fail; j++) {
1806 const char *rule = ref_rev_parse_rules[j];
1807 unsigned char short_objectname[20];
1808 char refname[PATH_MAX];
1810 /* skip matched rule */
1811 if (i == j)
1812 continue;
1815 * the short name is ambiguous, if it resolves
1816 * (with this previous rule) to a valid ref
1817 * read_ref() returns 0 on success
1819 mksnpath(refname, sizeof(refname),
1820 rule, short_name_len, short_name);
1821 if (!read_ref(refname, short_objectname))
1822 break;
1826 * short name is non-ambiguous if all previous rules
1827 * haven't resolved to a valid ref
1829 if (j == rules_to_fail)
1830 return short_name;
1833 free(short_name);
1834 return xstrdup(ref);