builtin-mailinfo.c: check error status from rewind and ftruncate
[git/spearce.git] / refs.c
blob808f56bb27b6ece616f400154fe98c9cef12f8ba
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 struct ref_list *extra_refs;
164 static void free_ref_list(struct ref_list *list)
166 struct ref_list *next;
167 for ( ; list; list = next) {
168 next = list->next;
169 free(list);
173 static void invalidate_cached_refs(void)
175 struct cached_refs *ca = &cached_refs;
177 if (ca->did_loose && ca->loose)
178 free_ref_list(ca->loose);
179 if (ca->did_packed && ca->packed)
180 free_ref_list(ca->packed);
181 ca->loose = ca->packed = NULL;
182 ca->did_loose = ca->did_packed = 0;
185 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
187 struct ref_list *list = NULL;
188 struct ref_list *last = NULL;
189 char refline[PATH_MAX];
190 int flag = REF_ISPACKED;
192 while (fgets(refline, sizeof(refline), f)) {
193 unsigned char sha1[20];
194 const char *name;
195 static const char header[] = "# pack-refs with:";
197 if (!strncmp(refline, header, sizeof(header)-1)) {
198 const char *traits = refline + sizeof(header) - 1;
199 if (strstr(traits, " peeled "))
200 flag |= REF_KNOWS_PEELED;
201 /* perhaps other traits later as well */
202 continue;
205 name = parse_ref_line(refline, sha1);
206 if (name) {
207 list = add_ref(name, sha1, flag, list, &last);
208 continue;
210 if (last &&
211 refline[0] == '^' &&
212 strlen(refline) == 42 &&
213 refline[41] == '\n' &&
214 !get_sha1_hex(refline + 1, sha1))
215 hashcpy(last->peeled, sha1);
217 cached_refs->packed = sort_ref_list(list);
220 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
222 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
225 void clear_extra_refs(void)
227 free_ref_list(extra_refs);
228 extra_refs = NULL;
231 static struct ref_list *get_packed_refs(void)
233 if (!cached_refs.did_packed) {
234 FILE *f = fopen(git_path("packed-refs"), "r");
235 cached_refs.packed = NULL;
236 if (f) {
237 read_packed_refs(f, &cached_refs);
238 fclose(f);
240 cached_refs.did_packed = 1;
242 return cached_refs.packed;
245 static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
247 DIR *dir = opendir(git_path("%s", base));
249 if (dir) {
250 struct dirent *de;
251 int baselen = strlen(base);
252 char *ref = xmalloc(baselen + 257);
254 memcpy(ref, base, baselen);
255 if (baselen && base[baselen-1] != '/')
256 ref[baselen++] = '/';
258 while ((de = readdir(dir)) != NULL) {
259 unsigned char sha1[20];
260 struct stat st;
261 int flag;
262 int namelen;
264 if (de->d_name[0] == '.')
265 continue;
266 namelen = strlen(de->d_name);
267 if (namelen > 255)
268 continue;
269 if (has_extension(de->d_name, ".lock"))
270 continue;
271 memcpy(ref + baselen, de->d_name, namelen+1);
272 if (stat(git_path("%s", ref), &st) < 0)
273 continue;
274 if (S_ISDIR(st.st_mode)) {
275 list = get_ref_dir(ref, list);
276 continue;
278 if (!resolve_ref(ref, sha1, 1, &flag))
279 hashclr(sha1);
280 list = add_ref(ref, sha1, flag, list, NULL);
282 free(ref);
283 closedir(dir);
285 return sort_ref_list(list);
288 struct warn_if_dangling_data {
289 const char *refname;
290 const char *msg_fmt;
293 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
294 int flags, void *cb_data)
296 struct warn_if_dangling_data *d = cb_data;
297 const char *resolves_to;
298 unsigned char junk[20];
300 if (!(flags & REF_ISSYMREF))
301 return 0;
303 resolves_to = resolve_ref(refname, junk, 0, NULL);
304 if (!resolves_to || strcmp(resolves_to, d->refname))
305 return 0;
307 printf(d->msg_fmt, refname);
308 return 0;
311 void warn_dangling_symref(const char *msg_fmt, const char *refname)
313 struct warn_if_dangling_data data = { refname, msg_fmt };
314 for_each_rawref(warn_if_dangling_symref, &data);
317 static struct ref_list *get_loose_refs(void)
319 if (!cached_refs.did_loose) {
320 cached_refs.loose = get_ref_dir("refs", NULL);
321 cached_refs.did_loose = 1;
323 return cached_refs.loose;
326 /* We allow "recursive" symbolic refs. Only within reason, though */
327 #define MAXDEPTH 5
328 #define MAXREFLEN (1024)
330 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
332 FILE *f;
333 struct cached_refs refs;
334 struct ref_list *ref;
335 int retval;
337 strcpy(name + pathlen, "packed-refs");
338 f = fopen(name, "r");
339 if (!f)
340 return -1;
341 read_packed_refs(f, &refs);
342 fclose(f);
343 ref = refs.packed;
344 retval = -1;
345 while (ref) {
346 if (!strcmp(ref->name, refname)) {
347 retval = 0;
348 memcpy(result, ref->sha1, 20);
349 break;
351 ref = ref->next;
353 free_ref_list(refs.packed);
354 return retval;
357 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
359 int fd, len = strlen(refname);
360 char buffer[128], *p;
362 if (recursion > MAXDEPTH || len > MAXREFLEN)
363 return -1;
364 memcpy(name + pathlen, refname, len+1);
365 fd = open(name, O_RDONLY);
366 if (fd < 0)
367 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
369 len = read(fd, buffer, sizeof(buffer)-1);
370 close(fd);
371 if (len < 0)
372 return -1;
373 while (len && isspace(buffer[len-1]))
374 len--;
375 buffer[len] = 0;
377 /* Was it a detached head or an old-fashioned symlink? */
378 if (!get_sha1_hex(buffer, result))
379 return 0;
381 /* Symref? */
382 if (strncmp(buffer, "ref:", 4))
383 return -1;
384 p = buffer + 4;
385 while (isspace(*p))
386 p++;
388 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
391 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
393 int len = strlen(path), retval;
394 char *gitdir;
395 const char *tmp;
397 while (len && path[len-1] == '/')
398 len--;
399 if (!len)
400 return -1;
401 gitdir = xmalloc(len + MAXREFLEN + 8);
402 memcpy(gitdir, path, len);
403 memcpy(gitdir + len, "/.git", 6);
404 len += 5;
406 tmp = read_gitfile_gently(gitdir);
407 if (tmp) {
408 free(gitdir);
409 len = strlen(tmp);
410 gitdir = xmalloc(len + MAXREFLEN + 3);
411 memcpy(gitdir, tmp, len);
413 gitdir[len] = '/';
414 gitdir[++len] = '\0';
415 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
416 free(gitdir);
417 return retval;
421 * If the "reading" argument is set, this function finds out what _object_
422 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
423 * has to exist, and if it is symbolic, it has to point at an existing ref,
424 * because the "read" goes through the symref to the ref it points at.
426 * The access that is not "reading" may often be "writing", but does not
427 * have to; it can be merely checking _where it leads to_. If it is a
428 * prelude to "writing" to the ref, a write to a symref that points at
429 * yet-to-be-born ref will create the real ref pointed by the symref.
430 * reading=0 allows the caller to check where such a symref leads to.
432 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
434 int depth = MAXDEPTH;
435 ssize_t len;
436 char buffer[256];
437 static char ref_buffer[256];
439 if (flag)
440 *flag = 0;
442 for (;;) {
443 char path[PATH_MAX];
444 struct stat st;
445 char *buf;
446 int fd;
448 if (--depth < 0)
449 return NULL;
451 git_snpath(path, sizeof(path), "%s", ref);
452 /* Special case: non-existing file. */
453 if (lstat(path, &st) < 0) {
454 struct ref_list *list = get_packed_refs();
455 while (list) {
456 if (!strcmp(ref, list->name)) {
457 hashcpy(sha1, list->sha1);
458 if (flag)
459 *flag |= REF_ISPACKED;
460 return ref;
462 list = list->next;
464 if (reading || errno != ENOENT)
465 return NULL;
466 hashclr(sha1);
467 return ref;
470 /* Follow "normalized" - ie "refs/.." symlinks by hand */
471 if (S_ISLNK(st.st_mode)) {
472 len = readlink(path, buffer, sizeof(buffer)-1);
473 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
474 buffer[len] = 0;
475 strcpy(ref_buffer, buffer);
476 ref = ref_buffer;
477 if (flag)
478 *flag |= REF_ISSYMREF;
479 continue;
483 /* Is it a directory? */
484 if (S_ISDIR(st.st_mode)) {
485 errno = EISDIR;
486 return NULL;
490 * Anything else, just open it and try to use it as
491 * a ref
493 fd = open(path, O_RDONLY);
494 if (fd < 0)
495 return NULL;
496 len = read_in_full(fd, buffer, sizeof(buffer)-1);
497 close(fd);
500 * Is it a symbolic ref?
502 if (len < 4 || memcmp("ref:", buffer, 4))
503 break;
504 buf = buffer + 4;
505 len -= 4;
506 while (len && isspace(*buf))
507 buf++, len--;
508 while (len && isspace(buf[len-1]))
509 len--;
510 buf[len] = 0;
511 memcpy(ref_buffer, buf, len + 1);
512 ref = ref_buffer;
513 if (flag)
514 *flag |= REF_ISSYMREF;
516 if (len < 40 || get_sha1_hex(buffer, sha1))
517 return NULL;
518 return ref;
521 int read_ref(const char *ref, unsigned char *sha1)
523 if (resolve_ref(ref, sha1, 1, NULL))
524 return 0;
525 return -1;
528 #define DO_FOR_EACH_INCLUDE_BROKEN 01
529 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
530 int flags, void *cb_data, struct ref_list *entry)
532 if (strncmp(base, entry->name, trim))
533 return 0;
534 /* Is this a "negative ref" that represents a deleted ref? */
535 if (is_null_sha1(entry->sha1))
536 return 0;
537 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
538 if (!has_sha1_file(entry->sha1)) {
539 error("%s does not point to a valid object!", entry->name);
540 return 0;
543 current_ref = entry;
544 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
547 int peel_ref(const char *ref, unsigned char *sha1)
549 int flag;
550 unsigned char base[20];
551 struct object *o;
553 if (current_ref && (current_ref->name == ref
554 || !strcmp(current_ref->name, ref))) {
555 if (current_ref->flag & REF_KNOWS_PEELED) {
556 hashcpy(sha1, current_ref->peeled);
557 return 0;
559 hashcpy(base, current_ref->sha1);
560 goto fallback;
563 if (!resolve_ref(ref, base, 1, &flag))
564 return -1;
566 if ((flag & REF_ISPACKED)) {
567 struct ref_list *list = get_packed_refs();
569 while (list) {
570 if (!strcmp(list->name, ref)) {
571 if (list->flag & REF_KNOWS_PEELED) {
572 hashcpy(sha1, list->peeled);
573 return 0;
575 /* older pack-refs did not leave peeled ones */
576 break;
578 list = list->next;
582 fallback:
583 o = parse_object(base);
584 if (o && o->type == OBJ_TAG) {
585 o = deref_tag(o, ref, 0);
586 if (o) {
587 hashcpy(sha1, o->sha1);
588 return 0;
591 return -1;
594 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
595 int flags, void *cb_data)
597 int retval = 0;
598 struct ref_list *packed = get_packed_refs();
599 struct ref_list *loose = get_loose_refs();
601 struct ref_list *extra;
603 for (extra = extra_refs; extra; extra = extra->next)
604 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
606 while (packed && loose) {
607 struct ref_list *entry;
608 int cmp = strcmp(packed->name, loose->name);
609 if (!cmp) {
610 packed = packed->next;
611 continue;
613 if (cmp > 0) {
614 entry = loose;
615 loose = loose->next;
616 } else {
617 entry = packed;
618 packed = packed->next;
620 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
621 if (retval)
622 goto end_each;
625 for (packed = packed ? packed : loose; packed; packed = packed->next) {
626 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
627 if (retval)
628 goto end_each;
631 end_each:
632 current_ref = NULL;
633 return retval;
636 int head_ref(each_ref_fn fn, void *cb_data)
638 unsigned char sha1[20];
639 int flag;
641 if (resolve_ref("HEAD", sha1, 1, &flag))
642 return fn("HEAD", sha1, flag, cb_data);
643 return 0;
646 int for_each_ref(each_ref_fn fn, void *cb_data)
648 return do_for_each_ref("refs/", fn, 0, 0, cb_data);
651 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
653 return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
656 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
658 return for_each_ref_in("refs/tags/", fn, cb_data);
661 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
663 return for_each_ref_in("refs/heads/", fn, cb_data);
666 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
668 return for_each_ref_in("refs/remotes/", fn, cb_data);
671 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
673 return do_for_each_ref("refs/replace/", fn, 13, 0, cb_data);
676 int for_each_rawref(each_ref_fn fn, void *cb_data)
678 return do_for_each_ref("refs/", fn, 0,
679 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
683 * Make sure "ref" is something reasonable to have under ".git/refs/";
684 * We do not like it if:
686 * - any path component of it begins with ".", or
687 * - it has double dots "..", or
688 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
689 * - it ends with a "/".
690 * - it ends with ".lock"
691 * - it contains a "\" (backslash)
694 static inline int bad_ref_char(int ch)
696 if (((unsigned) ch) <= ' ' ||
697 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
698 return 1;
699 /* 2.13 Pattern Matching Notation */
700 if (ch == '?' || ch == '[') /* Unsupported */
701 return 1;
702 if (ch == '*') /* Supported at the end */
703 return 2;
704 return 0;
707 int check_ref_format(const char *ref)
709 int ch, level, bad_type, last;
710 int ret = CHECK_REF_FORMAT_OK;
711 const char *cp = ref;
713 level = 0;
714 while (1) {
715 while ((ch = *cp++) == '/')
716 ; /* tolerate duplicated slashes */
717 if (!ch)
718 /* should not end with slashes */
719 return CHECK_REF_FORMAT_ERROR;
721 /* we are at the beginning of the path component */
722 if (ch == '.')
723 return CHECK_REF_FORMAT_ERROR;
724 bad_type = bad_ref_char(ch);
725 if (bad_type) {
726 if (bad_type == 2 && (!*cp || *cp == '/') &&
727 ret == CHECK_REF_FORMAT_OK)
728 ret = CHECK_REF_FORMAT_WILDCARD;
729 else
730 return CHECK_REF_FORMAT_ERROR;
733 last = ch;
734 /* scan the rest of the path component */
735 while ((ch = *cp++) != 0) {
736 bad_type = bad_ref_char(ch);
737 if (bad_type)
738 return CHECK_REF_FORMAT_ERROR;
739 if (ch == '/')
740 break;
741 if (last == '.' && ch == '.')
742 return CHECK_REF_FORMAT_ERROR;
743 if (last == '@' && ch == '{')
744 return CHECK_REF_FORMAT_ERROR;
745 last = ch;
747 level++;
748 if (!ch) {
749 if (ref <= cp - 2 && cp[-2] == '.')
750 return CHECK_REF_FORMAT_ERROR;
751 if (level < 2)
752 return CHECK_REF_FORMAT_ONELEVEL;
753 if (has_extension(ref, ".lock"))
754 return CHECK_REF_FORMAT_ERROR;
755 return ret;
760 const char *prettify_refname(const char *name)
762 return name + (
763 !prefixcmp(name, "refs/heads/") ? 11 :
764 !prefixcmp(name, "refs/tags/") ? 10 :
765 !prefixcmp(name, "refs/remotes/") ? 13 :
769 const char *ref_rev_parse_rules[] = {
770 "%.*s",
771 "refs/%.*s",
772 "refs/tags/%.*s",
773 "refs/heads/%.*s",
774 "refs/remotes/%.*s",
775 "refs/remotes/%.*s/HEAD",
776 NULL
779 const char *ref_fetch_rules[] = {
780 "%.*s",
781 "refs/%.*s",
782 "refs/heads/%.*s",
783 NULL
786 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
788 const char **p;
789 const int abbrev_name_len = strlen(abbrev_name);
791 for (p = rules; *p; p++) {
792 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
793 return 1;
797 return 0;
800 static struct ref_lock *verify_lock(struct ref_lock *lock,
801 const unsigned char *old_sha1, int mustexist)
803 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
804 error("Can't verify ref %s", lock->ref_name);
805 unlock_ref(lock);
806 return NULL;
808 if (hashcmp(lock->old_sha1, old_sha1)) {
809 error("Ref %s is at %s but expected %s", lock->ref_name,
810 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
811 unlock_ref(lock);
812 return NULL;
814 return lock;
817 static int remove_empty_directories(const char *file)
819 /* we want to create a file but there is a directory there;
820 * if that is an empty directory (or a directory that contains
821 * only empty directories), remove them.
823 struct strbuf path;
824 int result;
826 strbuf_init(&path, 20);
827 strbuf_addstr(&path, file);
829 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
831 strbuf_release(&path);
833 return result;
836 static int is_refname_available(const char *ref, const char *oldref,
837 struct ref_list *list, int quiet)
839 int namlen = strlen(ref); /* e.g. 'foo/bar' */
840 while (list) {
841 /* list->name could be 'foo' or 'foo/bar/baz' */
842 if (!oldref || strcmp(oldref, list->name)) {
843 int len = strlen(list->name);
844 int cmplen = (namlen < len) ? namlen : len;
845 const char *lead = (namlen < len) ? list->name : ref;
846 if (!strncmp(ref, list->name, cmplen) &&
847 lead[cmplen] == '/') {
848 if (!quiet)
849 error("'%s' exists; cannot create '%s'",
850 list->name, ref);
851 return 0;
854 list = list->next;
856 return 1;
859 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
861 char *ref_file;
862 const char *orig_ref = ref;
863 struct ref_lock *lock;
864 int last_errno = 0;
865 int type, lflags;
866 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
867 int missing = 0;
869 lock = xcalloc(1, sizeof(struct ref_lock));
870 lock->lock_fd = -1;
872 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
873 if (!ref && errno == EISDIR) {
874 /* we are trying to lock foo but we used to
875 * have foo/bar which now does not exist;
876 * it is normal for the empty directory 'foo'
877 * to remain.
879 ref_file = git_path("%s", orig_ref);
880 if (remove_empty_directories(ref_file)) {
881 last_errno = errno;
882 error("there are still refs under '%s'", orig_ref);
883 goto error_return;
885 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
887 if (type_p)
888 *type_p = type;
889 if (!ref) {
890 last_errno = errno;
891 error("unable to resolve reference %s: %s",
892 orig_ref, strerror(errno));
893 goto error_return;
895 missing = is_null_sha1(lock->old_sha1);
896 /* When the ref did not exist and we are creating it,
897 * make sure there is no existing ref that is packed
898 * whose name begins with our refname, nor a ref whose
899 * name is a proper prefix of our refname.
901 if (missing &&
902 !is_refname_available(ref, NULL, get_packed_refs(), 0)) {
903 last_errno = ENOTDIR;
904 goto error_return;
907 lock->lk = xcalloc(1, sizeof(struct lock_file));
909 lflags = LOCK_DIE_ON_ERROR;
910 if (flags & REF_NODEREF) {
911 ref = orig_ref;
912 lflags |= LOCK_NODEREF;
914 lock->ref_name = xstrdup(ref);
915 lock->orig_ref_name = xstrdup(orig_ref);
916 ref_file = git_path("%s", ref);
917 if (missing)
918 lock->force_write = 1;
919 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
920 lock->force_write = 1;
922 if (safe_create_leading_directories(ref_file)) {
923 last_errno = errno;
924 error("unable to create directory for %s", ref_file);
925 goto error_return;
928 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
929 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
931 error_return:
932 unlock_ref(lock);
933 errno = last_errno;
934 return NULL;
937 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
939 char refpath[PATH_MAX];
940 if (check_ref_format(ref))
941 return NULL;
942 strcpy(refpath, mkpath("refs/%s", ref));
943 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
946 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
948 switch (check_ref_format(ref)) {
949 default:
950 return NULL;
951 case 0:
952 case CHECK_REF_FORMAT_ONELEVEL:
953 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
957 static struct lock_file packlock;
959 static int repack_without_ref(const char *refname)
961 struct ref_list *list, *packed_ref_list;
962 int fd;
963 int found = 0;
965 packed_ref_list = get_packed_refs();
966 for (list = packed_ref_list; list; list = list->next) {
967 if (!strcmp(refname, list->name)) {
968 found = 1;
969 break;
972 if (!found)
973 return 0;
974 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
975 if (fd < 0) {
976 unable_to_lock_error(git_path("packed-refs"), errno);
977 return error("cannot delete '%s' from packed refs", refname);
980 for (list = packed_ref_list; list; list = list->next) {
981 char line[PATH_MAX + 100];
982 int len;
984 if (!strcmp(refname, list->name))
985 continue;
986 len = snprintf(line, sizeof(line), "%s %s\n",
987 sha1_to_hex(list->sha1), list->name);
988 /* this should not happen but just being defensive */
989 if (len > sizeof(line))
990 die("too long a refname '%s'", list->name);
991 write_or_die(fd, line, len);
993 return commit_lock_file(&packlock);
996 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
998 struct ref_lock *lock;
999 int err, i = 0, ret = 0, flag = 0;
1001 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1002 if (!lock)
1003 return 1;
1004 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1005 /* loose */
1006 const char *path;
1008 if (!(delopt & REF_NODEREF)) {
1009 i = strlen(lock->lk->filename) - 5; /* .lock */
1010 lock->lk->filename[i] = 0;
1011 path = lock->lk->filename;
1012 } else {
1013 path = git_path("%s", refname);
1015 err = unlink_or_warn(path);
1016 if (err && errno != ENOENT)
1017 ret = 1;
1019 if (!(delopt & REF_NODEREF))
1020 lock->lk->filename[i] = '.';
1022 /* removing the loose one could have resurrected an earlier
1023 * packed one. Also, if it was not loose we need to repack
1024 * without it.
1026 ret |= repack_without_ref(refname);
1028 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1029 invalidate_cached_refs();
1030 unlock_ref(lock);
1031 return ret;
1034 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1036 static const char renamed_ref[] = "RENAMED-REF";
1037 unsigned char sha1[20], orig_sha1[20];
1038 int flag = 0, logmoved = 0;
1039 struct ref_lock *lock;
1040 struct stat loginfo;
1041 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1042 const char *symref = NULL;
1044 if (log && S_ISLNK(loginfo.st_mode))
1045 return error("reflog for %s is a symlink", oldref);
1047 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1048 if (flag & REF_ISSYMREF)
1049 return error("refname %s is a symbolic ref, renaming it is not supported",
1050 oldref);
1051 if (!symref)
1052 return error("refname %s not found", oldref);
1054 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1055 return 1;
1057 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1058 return 1;
1060 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1061 if (!lock)
1062 return error("unable to lock %s", renamed_ref);
1063 lock->force_write = 1;
1064 if (write_ref_sha1(lock, orig_sha1, logmsg))
1065 return error("unable to save current sha1 in %s", renamed_ref);
1067 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1068 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1069 oldref, strerror(errno));
1071 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1072 error("unable to delete old %s", oldref);
1073 goto rollback;
1076 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1077 if (errno==EISDIR) {
1078 if (remove_empty_directories(git_path("%s", newref))) {
1079 error("Directory not empty: %s", newref);
1080 goto rollback;
1082 } else {
1083 error("unable to delete existing %s", newref);
1084 goto rollback;
1088 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1089 error("unable to create directory for %s", newref);
1090 goto rollback;
1093 retry:
1094 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
1095 if (errno==EISDIR || errno==ENOTDIR) {
1097 * rename(a, b) when b is an existing
1098 * directory ought to result in ISDIR, but
1099 * Solaris 5.8 gives ENOTDIR. Sheesh.
1101 if (remove_empty_directories(git_path("logs/%s", newref))) {
1102 error("Directory not empty: logs/%s", newref);
1103 goto rollback;
1105 goto retry;
1106 } else {
1107 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1108 newref, strerror(errno));
1109 goto rollback;
1112 logmoved = log;
1114 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1115 if (!lock) {
1116 error("unable to lock %s for update", newref);
1117 goto rollback;
1119 lock->force_write = 1;
1120 hashcpy(lock->old_sha1, orig_sha1);
1121 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1122 error("unable to write current sha1 into %s", newref);
1123 goto rollback;
1126 return 0;
1128 rollback:
1129 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1130 if (!lock) {
1131 error("unable to lock %s for rollback", oldref);
1132 goto rollbacklog;
1135 lock->force_write = 1;
1136 flag = log_all_ref_updates;
1137 log_all_ref_updates = 0;
1138 if (write_ref_sha1(lock, orig_sha1, NULL))
1139 error("unable to write current sha1 into %s", oldref);
1140 log_all_ref_updates = flag;
1142 rollbacklog:
1143 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1144 error("unable to restore logfile %s from %s: %s",
1145 oldref, newref, strerror(errno));
1146 if (!logmoved && log &&
1147 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1148 error("unable to restore logfile %s from tmp-renamed-log: %s",
1149 oldref, strerror(errno));
1151 return 1;
1154 int close_ref(struct ref_lock *lock)
1156 if (close_lock_file(lock->lk))
1157 return -1;
1158 lock->lock_fd = -1;
1159 return 0;
1162 int commit_ref(struct ref_lock *lock)
1164 if (commit_lock_file(lock->lk))
1165 return -1;
1166 lock->lock_fd = -1;
1167 return 0;
1170 void unlock_ref(struct ref_lock *lock)
1172 /* Do not free lock->lk -- atexit() still looks at them */
1173 if (lock->lk)
1174 rollback_lock_file(lock->lk);
1175 free(lock->ref_name);
1176 free(lock->orig_ref_name);
1177 free(lock);
1181 * copy the reflog message msg to buf, which has been allocated sufficiently
1182 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1183 * because reflog file is one line per entry.
1185 static int copy_msg(char *buf, const char *msg)
1187 char *cp = buf;
1188 char c;
1189 int wasspace = 1;
1191 *cp++ = '\t';
1192 while ((c = *msg++)) {
1193 if (wasspace && isspace(c))
1194 continue;
1195 wasspace = isspace(c);
1196 if (wasspace)
1197 c = ' ';
1198 *cp++ = c;
1200 while (buf < cp && isspace(cp[-1]))
1201 cp--;
1202 *cp++ = '\n';
1203 return cp - buf;
1206 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1207 const unsigned char *new_sha1, const char *msg)
1209 int logfd, written, oflags = O_APPEND | O_WRONLY;
1210 unsigned maxlen, len;
1211 int msglen;
1212 char log_file[PATH_MAX];
1213 char *logrec;
1214 const char *committer;
1216 if (log_all_ref_updates < 0)
1217 log_all_ref_updates = !is_bare_repository();
1219 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
1221 if (log_all_ref_updates &&
1222 (!prefixcmp(ref_name, "refs/heads/") ||
1223 !prefixcmp(ref_name, "refs/remotes/") ||
1224 !strcmp(ref_name, "HEAD"))) {
1225 if (safe_create_leading_directories(log_file) < 0)
1226 return error("unable to create directory for %s",
1227 log_file);
1228 oflags |= O_CREAT;
1231 logfd = open(log_file, oflags, 0666);
1232 if (logfd < 0) {
1233 if (!(oflags & O_CREAT) && errno == ENOENT)
1234 return 0;
1236 if ((oflags & O_CREAT) && errno == EISDIR) {
1237 if (remove_empty_directories(log_file)) {
1238 return error("There are still logs under '%s'",
1239 log_file);
1241 logfd = open(log_file, oflags, 0666);
1244 if (logfd < 0)
1245 return error("Unable to append to %s: %s",
1246 log_file, strerror(errno));
1249 adjust_shared_perm(log_file);
1251 msglen = msg ? strlen(msg) : 0;
1252 committer = git_committer_info(0);
1253 maxlen = strlen(committer) + msglen + 100;
1254 logrec = xmalloc(maxlen);
1255 len = sprintf(logrec, "%s %s %s\n",
1256 sha1_to_hex(old_sha1),
1257 sha1_to_hex(new_sha1),
1258 committer);
1259 if (msglen)
1260 len += copy_msg(logrec + len - 1, msg) - 1;
1261 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1262 free(logrec);
1263 if (close(logfd) != 0 || written != len)
1264 return error("Unable to append to %s", log_file);
1265 return 0;
1268 static int is_branch(const char *refname)
1270 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1273 int write_ref_sha1(struct ref_lock *lock,
1274 const unsigned char *sha1, const char *logmsg)
1276 static char term = '\n';
1277 struct object *o;
1279 if (!lock)
1280 return -1;
1281 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1282 unlock_ref(lock);
1283 return 0;
1285 o = parse_object(sha1);
1286 if (!o) {
1287 error("Trying to write ref %s with nonexistant object %s",
1288 lock->ref_name, sha1_to_hex(sha1));
1289 unlock_ref(lock);
1290 return -1;
1292 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1293 error("Trying to write non-commit object %s to branch %s",
1294 sha1_to_hex(sha1), lock->ref_name);
1295 unlock_ref(lock);
1296 return -1;
1298 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1299 write_in_full(lock->lock_fd, &term, 1) != 1
1300 || close_ref(lock) < 0) {
1301 error("Couldn't write %s", lock->lk->filename);
1302 unlock_ref(lock);
1303 return -1;
1305 invalidate_cached_refs();
1306 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1307 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1308 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1309 unlock_ref(lock);
1310 return -1;
1312 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1314 * Special hack: If a branch is updated directly and HEAD
1315 * points to it (may happen on the remote side of a push
1316 * for example) then logically the HEAD reflog should be
1317 * updated too.
1318 * A generic solution implies reverse symref information,
1319 * but finding all symrefs pointing to the given branch
1320 * would be rather costly for this rare event (the direct
1321 * update of a branch) to be worth it. So let's cheat and
1322 * check with HEAD only which should cover 99% of all usage
1323 * scenarios (even 100% of the default ones).
1325 unsigned char head_sha1[20];
1326 int head_flag;
1327 const char *head_ref;
1328 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1329 if (head_ref && (head_flag & REF_ISSYMREF) &&
1330 !strcmp(head_ref, lock->ref_name))
1331 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1333 if (commit_ref(lock)) {
1334 error("Couldn't set %s", lock->ref_name);
1335 unlock_ref(lock);
1336 return -1;
1338 unlock_ref(lock);
1339 return 0;
1342 int create_symref(const char *ref_target, const char *refs_heads_master,
1343 const char *logmsg)
1345 const char *lockpath;
1346 char ref[1000];
1347 int fd, len, written;
1348 char *git_HEAD = git_pathdup("%s", ref_target);
1349 unsigned char old_sha1[20], new_sha1[20];
1351 if (logmsg && read_ref(ref_target, old_sha1))
1352 hashclr(old_sha1);
1354 if (safe_create_leading_directories(git_HEAD) < 0)
1355 return error("unable to create directory for %s", git_HEAD);
1357 #ifndef NO_SYMLINK_HEAD
1358 if (prefer_symlink_refs) {
1359 unlink(git_HEAD);
1360 if (!symlink(refs_heads_master, git_HEAD))
1361 goto done;
1362 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1364 #endif
1366 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1367 if (sizeof(ref) <= len) {
1368 error("refname too long: %s", refs_heads_master);
1369 goto error_free_return;
1371 lockpath = mkpath("%s.lock", git_HEAD);
1372 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1373 if (fd < 0) {
1374 error("Unable to open %s for writing", lockpath);
1375 goto error_free_return;
1377 written = write_in_full(fd, ref, len);
1378 if (close(fd) != 0 || written != len) {
1379 error("Unable to write to %s", lockpath);
1380 goto error_unlink_return;
1382 if (rename(lockpath, git_HEAD) < 0) {
1383 error("Unable to create %s", git_HEAD);
1384 goto error_unlink_return;
1386 if (adjust_shared_perm(git_HEAD)) {
1387 error("Unable to fix permissions on %s", lockpath);
1388 error_unlink_return:
1389 unlink_or_warn(lockpath);
1390 error_free_return:
1391 free(git_HEAD);
1392 return -1;
1395 #ifndef NO_SYMLINK_HEAD
1396 done:
1397 #endif
1398 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1399 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1401 free(git_HEAD);
1402 return 0;
1405 static char *ref_msg(const char *line, const char *endp)
1407 const char *ep;
1408 line += 82;
1409 ep = memchr(line, '\n', endp - line);
1410 if (!ep)
1411 ep = endp;
1412 return xmemdupz(line, ep - line);
1415 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)
1417 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1418 char *tz_c;
1419 int logfd, tz, reccnt = 0;
1420 struct stat st;
1421 unsigned long date;
1422 unsigned char logged_sha1[20];
1423 void *log_mapped;
1424 size_t mapsz;
1426 logfile = git_path("logs/%s", ref);
1427 logfd = open(logfile, O_RDONLY, 0);
1428 if (logfd < 0)
1429 die_errno("Unable to read log '%s'", logfile);
1430 fstat(logfd, &st);
1431 if (!st.st_size)
1432 die("Log %s is empty.", logfile);
1433 mapsz = xsize_t(st.st_size);
1434 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1435 logdata = log_mapped;
1436 close(logfd);
1438 lastrec = NULL;
1439 rec = logend = logdata + st.st_size;
1440 while (logdata < rec) {
1441 reccnt++;
1442 if (logdata < rec && *(rec-1) == '\n')
1443 rec--;
1444 lastgt = NULL;
1445 while (logdata < rec && *(rec-1) != '\n') {
1446 rec--;
1447 if (*rec == '>')
1448 lastgt = rec;
1450 if (!lastgt)
1451 die("Log %s is corrupt.", logfile);
1452 date = strtoul(lastgt + 1, &tz_c, 10);
1453 if (date <= at_time || cnt == 0) {
1454 tz = strtoul(tz_c, NULL, 10);
1455 if (msg)
1456 *msg = ref_msg(rec, logend);
1457 if (cutoff_time)
1458 *cutoff_time = date;
1459 if (cutoff_tz)
1460 *cutoff_tz = tz;
1461 if (cutoff_cnt)
1462 *cutoff_cnt = reccnt - 1;
1463 if (lastrec) {
1464 if (get_sha1_hex(lastrec, logged_sha1))
1465 die("Log %s is corrupt.", logfile);
1466 if (get_sha1_hex(rec + 41, sha1))
1467 die("Log %s is corrupt.", logfile);
1468 if (hashcmp(logged_sha1, sha1)) {
1469 warning("Log %s has gap after %s.",
1470 logfile, show_date(date, tz, DATE_RFC2822));
1473 else if (date == at_time) {
1474 if (get_sha1_hex(rec + 41, sha1))
1475 die("Log %s is corrupt.", logfile);
1477 else {
1478 if (get_sha1_hex(rec + 41, logged_sha1))
1479 die("Log %s is corrupt.", logfile);
1480 if (hashcmp(logged_sha1, sha1)) {
1481 warning("Log %s unexpectedly ended on %s.",
1482 logfile, show_date(date, tz, DATE_RFC2822));
1485 munmap(log_mapped, mapsz);
1486 return 0;
1488 lastrec = rec;
1489 if (cnt > 0)
1490 cnt--;
1493 rec = logdata;
1494 while (rec < logend && *rec != '>' && *rec != '\n')
1495 rec++;
1496 if (rec == logend || *rec == '\n')
1497 die("Log %s is corrupt.", logfile);
1498 date = strtoul(rec + 1, &tz_c, 10);
1499 tz = strtoul(tz_c, NULL, 10);
1500 if (get_sha1_hex(logdata, sha1))
1501 die("Log %s is corrupt.", logfile);
1502 if (is_null_sha1(sha1)) {
1503 if (get_sha1_hex(logdata + 41, sha1))
1504 die("Log %s is corrupt.", logfile);
1506 if (msg)
1507 *msg = ref_msg(logdata, logend);
1508 munmap(log_mapped, mapsz);
1510 if (cutoff_time)
1511 *cutoff_time = date;
1512 if (cutoff_tz)
1513 *cutoff_tz = tz;
1514 if (cutoff_cnt)
1515 *cutoff_cnt = reccnt;
1516 return 1;
1519 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1521 const char *logfile;
1522 FILE *logfp;
1523 char buf[1024];
1524 int ret = 0;
1526 logfile = git_path("logs/%s", ref);
1527 logfp = fopen(logfile, "r");
1528 if (!logfp)
1529 return -1;
1531 if (ofs) {
1532 struct stat statbuf;
1533 if (fstat(fileno(logfp), &statbuf) ||
1534 statbuf.st_size < ofs ||
1535 fseek(logfp, -ofs, SEEK_END) ||
1536 fgets(buf, sizeof(buf), logfp)) {
1537 fclose(logfp);
1538 return -1;
1542 while (fgets(buf, sizeof(buf), logfp)) {
1543 unsigned char osha1[20], nsha1[20];
1544 char *email_end, *message;
1545 unsigned long timestamp;
1546 int len, tz;
1548 /* old SP new SP name <email> SP time TAB msg LF */
1549 len = strlen(buf);
1550 if (len < 83 || buf[len-1] != '\n' ||
1551 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
1552 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1553 !(email_end = strchr(buf + 82, '>')) ||
1554 email_end[1] != ' ' ||
1555 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1556 !message || message[0] != ' ' ||
1557 (message[1] != '+' && message[1] != '-') ||
1558 !isdigit(message[2]) || !isdigit(message[3]) ||
1559 !isdigit(message[4]) || !isdigit(message[5]))
1560 continue; /* corrupt? */
1561 email_end[1] = '\0';
1562 tz = strtol(message + 1, NULL, 10);
1563 if (message[6] != '\t')
1564 message += 6;
1565 else
1566 message += 7;
1567 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1568 if (ret)
1569 break;
1571 fclose(logfp);
1572 return ret;
1575 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1577 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1580 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1582 DIR *dir = opendir(git_path("logs/%s", base));
1583 int retval = 0;
1585 if (dir) {
1586 struct dirent *de;
1587 int baselen = strlen(base);
1588 char *log = xmalloc(baselen + 257);
1590 memcpy(log, base, baselen);
1591 if (baselen && base[baselen-1] != '/')
1592 log[baselen++] = '/';
1594 while ((de = readdir(dir)) != NULL) {
1595 struct stat st;
1596 int namelen;
1598 if (de->d_name[0] == '.')
1599 continue;
1600 namelen = strlen(de->d_name);
1601 if (namelen > 255)
1602 continue;
1603 if (has_extension(de->d_name, ".lock"))
1604 continue;
1605 memcpy(log + baselen, de->d_name, namelen+1);
1606 if (stat(git_path("logs/%s", log), &st) < 0)
1607 continue;
1608 if (S_ISDIR(st.st_mode)) {
1609 retval = do_for_each_reflog(log, fn, cb_data);
1610 } else {
1611 unsigned char sha1[20];
1612 if (!resolve_ref(log, sha1, 0, NULL))
1613 retval = error("bad ref for %s", log);
1614 else
1615 retval = fn(log, sha1, 0, cb_data);
1617 if (retval)
1618 break;
1620 free(log);
1621 closedir(dir);
1623 else if (*base)
1624 return errno;
1625 return retval;
1628 int for_each_reflog(each_ref_fn fn, void *cb_data)
1630 return do_for_each_reflog("", fn, cb_data);
1633 int update_ref(const char *action, const char *refname,
1634 const unsigned char *sha1, const unsigned char *oldval,
1635 int flags, enum action_on_err onerr)
1637 static struct ref_lock *lock;
1638 lock = lock_any_ref_for_update(refname, oldval, flags);
1639 if (!lock) {
1640 const char *str = "Cannot lock the ref '%s'.";
1641 switch (onerr) {
1642 case MSG_ON_ERR: error(str, refname); break;
1643 case DIE_ON_ERR: die(str, refname); break;
1644 case QUIET_ON_ERR: break;
1646 return 1;
1648 if (write_ref_sha1(lock, sha1, action) < 0) {
1649 const char *str = "Cannot update the ref '%s'.";
1650 switch (onerr) {
1651 case MSG_ON_ERR: error(str, refname); break;
1652 case DIE_ON_ERR: die(str, refname); break;
1653 case QUIET_ON_ERR: break;
1655 return 1;
1657 return 0;
1660 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1662 for ( ; list; list = list->next)
1663 if (!strcmp(list->name, name))
1664 return (struct ref *)list;
1665 return NULL;
1669 * generate a format suitable for scanf from a ref_rev_parse_rules
1670 * rule, that is replace the "%.*s" spec with a "%s" spec
1672 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1674 char *spec;
1676 spec = strstr(rule, "%.*s");
1677 if (!spec || strstr(spec + 4, "%.*s"))
1678 die("invalid rule in ref_rev_parse_rules: %s", rule);
1680 /* copy all until spec */
1681 strncpy(scanf_fmt, rule, spec - rule);
1682 scanf_fmt[spec - rule] = '\0';
1683 /* copy new spec */
1684 strcat(scanf_fmt, "%s");
1685 /* copy remaining rule */
1686 strcat(scanf_fmt, spec + 4);
1688 return;
1691 char *shorten_unambiguous_ref(const char *ref, int strict)
1693 int i;
1694 static char **scanf_fmts;
1695 static int nr_rules;
1696 char *short_name;
1698 /* pre generate scanf formats from ref_rev_parse_rules[] */
1699 if (!nr_rules) {
1700 size_t total_len = 0;
1702 /* the rule list is NULL terminated, count them first */
1703 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1704 /* no +1 because strlen("%s") < strlen("%.*s") */
1705 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1707 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1709 total_len = 0;
1710 for (i = 0; i < nr_rules; i++) {
1711 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1712 + total_len;
1713 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1714 total_len += strlen(ref_rev_parse_rules[i]);
1718 /* bail out if there are no rules */
1719 if (!nr_rules)
1720 return xstrdup(ref);
1722 /* buffer for scanf result, at most ref must fit */
1723 short_name = xstrdup(ref);
1725 /* skip first rule, it will always match */
1726 for (i = nr_rules - 1; i > 0 ; --i) {
1727 int j;
1728 int rules_to_fail = i;
1729 int short_name_len;
1731 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1732 continue;
1734 short_name_len = strlen(short_name);
1737 * in strict mode, all (except the matched one) rules
1738 * must fail to resolve to a valid non-ambiguous ref
1740 if (strict)
1741 rules_to_fail = nr_rules;
1744 * check if the short name resolves to a valid ref,
1745 * but use only rules prior to the matched one
1747 for (j = 0; j < rules_to_fail; j++) {
1748 const char *rule = ref_rev_parse_rules[j];
1749 unsigned char short_objectname[20];
1750 char refname[PATH_MAX];
1752 /* skip matched rule */
1753 if (i == j)
1754 continue;
1757 * the short name is ambiguous, if it resolves
1758 * (with this previous rule) to a valid ref
1759 * read_ref() returns 0 on success
1761 mksnpath(refname, sizeof(refname),
1762 rule, short_name_len, short_name);
1763 if (!read_ref(refname, short_objectname))
1764 break;
1768 * short name is non-ambiguous if all previous rules
1769 * haven't resolved to a valid ref
1771 if (j == rules_to_fail)
1772 return short_name;
1775 free(short_name);
1776 return xstrdup(ref);