7 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8 #define REF_KNOWS_PEELED 04
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;
33 if (get_sha1_hex(line, sha1) < 0)
35 if (!isspace(line[40]))
40 if (line[len] != '\n')
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)
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);
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;
80 last_merge_count = merge_count;
93 while (psize < k && q->next) {
99 while ((psize > 0) || (qsize > 0 && q)) {
100 if (qsize == 0 || !q) {
104 } else if (psize == 0) {
109 cmp = strcmp(q->name, p->name);
114 } else if (cmp > 0) {
119 if (hashcmp(q->sha1, p->sha1))
120 die("Duplicated ref, and SHA1s don't match: %s",
122 warning("Duplicated ref: %s", q->name);
146 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
152 * Future: need to be in "struct repository"
153 * when doing a full libification.
155 static struct cached_refs {
156 struct cached_refs *next;
159 struct ref_list *loose;
160 struct ref_list *packed;
161 /* The submodule name, or "" for the main repo. */
162 char name[FLEX_ARRAY];
165 static struct ref_list *current_ref;
167 static struct ref_list *extra_refs;
169 static void free_ref_list(struct ref_list *list)
171 struct ref_list *next;
172 for ( ; list; list = next) {
178 static void clear_cached_refs(struct cached_refs *ca)
180 if (ca->did_loose && ca->loose)
181 free_ref_list(ca->loose);
182 if (ca->did_packed && ca->packed)
183 free_ref_list(ca->packed);
184 ca->loose = ca->packed = NULL;
185 ca->did_loose = ca->did_packed = 0;
188 static struct cached_refs *create_cached_refs(const char *submodule)
191 struct cached_refs *refs;
194 len = strlen(submodule) + 1;
195 refs = xmalloc(sizeof(struct cached_refs) + len);
197 refs->did_loose = refs->did_packed = 0;
198 refs->loose = refs->packed = NULL;
199 memcpy(refs->name, submodule, len);
204 * Return a pointer to a cached_refs for the specified submodule. For
205 * the main repository, use submodule==NULL. The returned structure
206 * will be allocated and initialized but not necessarily populated; it
207 * should not be freed.
209 static struct cached_refs *get_cached_refs(const char *submodule)
211 struct cached_refs *refs = cached_refs;
215 if (!strcmp(submodule, refs->name))
220 refs = create_cached_refs(submodule);
221 refs->next = cached_refs;
226 static void invalidate_cached_refs(void)
228 struct cached_refs *refs = cached_refs;
230 clear_cached_refs(refs);
235 static struct ref_list *read_packed_refs(FILE *f)
237 struct ref_list *list = NULL;
238 struct ref_list *last = NULL;
239 char refline[PATH_MAX];
240 int flag = REF_ISPACKED;
242 while (fgets(refline, sizeof(refline), f)) {
243 unsigned char sha1[20];
245 static const char header[] = "# pack-refs with:";
247 if (!strncmp(refline, header, sizeof(header)-1)) {
248 const char *traits = refline + sizeof(header) - 1;
249 if (strstr(traits, " peeled "))
250 flag |= REF_KNOWS_PEELED;
251 /* perhaps other traits later as well */
255 name = parse_ref_line(refline, sha1);
257 list = add_ref(name, sha1, flag, list, &last);
262 strlen(refline) == 42 &&
263 refline[41] == '\n' &&
264 !get_sha1_hex(refline + 1, sha1))
265 hashcpy(last->peeled, sha1);
267 return sort_ref_list(list);
270 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
272 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
275 void clear_extra_refs(void)
277 free_ref_list(extra_refs);
281 static struct ref_list *get_packed_refs(const char *submodule)
283 struct cached_refs *refs = get_cached_refs(submodule);
285 if (!refs->did_packed) {
286 const char *packed_refs_file;
290 packed_refs_file = git_path_submodule(submodule, "packed-refs");
292 packed_refs_file = git_path("packed-refs");
293 f = fopen(packed_refs_file, "r");
296 refs->packed = read_packed_refs(f);
299 refs->did_packed = 1;
304 static struct ref_list *get_ref_dir(const char *submodule, const char *base,
305 struct ref_list *list)
311 path = git_path_submodule(submodule, "%s", base);
313 path = git_path("%s", base);
320 int baselen = strlen(base);
321 char *ref = xmalloc(baselen + 257);
323 memcpy(ref, base, baselen);
324 if (baselen && base[baselen-1] != '/')
325 ref[baselen++] = '/';
327 while ((de = readdir(dir)) != NULL) {
328 unsigned char sha1[20];
334 if (de->d_name[0] == '.')
336 namelen = strlen(de->d_name);
339 if (has_extension(de->d_name, ".lock"))
341 memcpy(ref + baselen, de->d_name, namelen+1);
343 ? git_path_submodule(submodule, "%s", ref)
344 : git_path("%s", ref);
345 if (stat(refdir, &st) < 0)
347 if (S_ISDIR(st.st_mode)) {
348 list = get_ref_dir(submodule, ref, list);
354 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
359 if (!resolve_ref(ref, sha1, 1, &flag)) {
363 list = add_ref(ref, sha1, flag, list, NULL);
368 return sort_ref_list(list);
371 struct warn_if_dangling_data {
377 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
378 int flags, void *cb_data)
380 struct warn_if_dangling_data *d = cb_data;
381 const char *resolves_to;
382 unsigned char junk[20];
384 if (!(flags & REF_ISSYMREF))
387 resolves_to = resolve_ref(refname, junk, 0, NULL);
388 if (!resolves_to || strcmp(resolves_to, d->refname))
391 fprintf(d->fp, d->msg_fmt, refname);
395 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
397 struct warn_if_dangling_data data;
400 data.refname = refname;
401 data.msg_fmt = msg_fmt;
402 for_each_rawref(warn_if_dangling_symref, &data);
405 static struct ref_list *get_loose_refs(const char *submodule)
407 struct cached_refs *refs = get_cached_refs(submodule);
409 if (!refs->did_loose) {
410 refs->loose = get_ref_dir(submodule, "refs", NULL);
416 /* We allow "recursive" symbolic refs. Only within reason, though */
418 #define MAXREFLEN (1024)
420 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
423 struct ref_list *packed_refs;
424 struct ref_list *ref;
427 strcpy(name + pathlen, "packed-refs");
428 f = fopen(name, "r");
431 packed_refs = read_packed_refs(f);
436 if (!strcmp(ref->name, refname)) {
438 memcpy(result, ref->sha1, 20);
443 free_ref_list(packed_refs);
447 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
449 int fd, len = strlen(refname);
450 char buffer[128], *p;
452 if (recursion > MAXDEPTH || len > MAXREFLEN)
454 memcpy(name + pathlen, refname, len+1);
455 fd = open(name, O_RDONLY);
457 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
459 len = read(fd, buffer, sizeof(buffer)-1);
463 while (len && isspace(buffer[len-1]))
467 /* Was it a detached head or an old-fashioned symlink? */
468 if (!get_sha1_hex(buffer, result))
472 if (strncmp(buffer, "ref:", 4))
478 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
481 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
483 int len = strlen(path), retval;
487 while (len && path[len-1] == '/')
491 gitdir = xmalloc(len + MAXREFLEN + 8);
492 memcpy(gitdir, path, len);
493 memcpy(gitdir + len, "/.git", 6);
496 tmp = read_gitfile(gitdir);
500 gitdir = xmalloc(len + MAXREFLEN + 3);
501 memcpy(gitdir, tmp, len);
504 gitdir[++len] = '\0';
505 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
511 * If the "reading" argument is set, this function finds out what _object_
512 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
513 * has to exist, and if it is symbolic, it has to point at an existing ref,
514 * because the "read" goes through the symref to the ref it points at.
516 * The access that is not "reading" may often be "writing", but does not
517 * have to; it can be merely checking _where it leads to_. If it is a
518 * prelude to "writing" to the ref, a write to a symref that points at
519 * yet-to-be-born ref will create the real ref pointed by the symref.
520 * reading=0 allows the caller to check where such a symref leads to.
522 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
524 int depth = MAXDEPTH;
527 static char ref_buffer[256];
541 git_snpath(path, sizeof(path), "%s", ref);
542 /* Special case: non-existing file. */
543 if (lstat(path, &st) < 0) {
544 struct ref_list *list = get_packed_refs(NULL);
546 if (!strcmp(ref, list->name)) {
547 hashcpy(sha1, list->sha1);
549 *flag |= REF_ISPACKED;
554 if (reading || errno != ENOENT)
560 /* Follow "normalized" - ie "refs/.." symlinks by hand */
561 if (S_ISLNK(st.st_mode)) {
562 len = readlink(path, buffer, sizeof(buffer)-1);
563 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
565 strcpy(ref_buffer, buffer);
568 *flag |= REF_ISSYMREF;
573 /* Is it a directory? */
574 if (S_ISDIR(st.st_mode)) {
580 * Anything else, just open it and try to use it as
583 fd = open(path, O_RDONLY);
586 len = read_in_full(fd, buffer, sizeof(buffer)-1);
590 * Is it a symbolic ref?
592 if (len < 4 || memcmp("ref:", buffer, 4))
596 while (len && isspace(*buf))
598 while (len && isspace(buf[len-1]))
601 memcpy(ref_buffer, buf, len + 1);
604 *flag |= REF_ISSYMREF;
606 if (len < 40 || get_sha1_hex(buffer, sha1))
611 /* The argument to filter_refs */
618 int read_ref(const char *ref, unsigned char *sha1)
620 if (resolve_ref(ref, sha1, 1, NULL))
625 #define DO_FOR_EACH_INCLUDE_BROKEN 01
626 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
627 int flags, void *cb_data, struct ref_list *entry)
629 if (prefixcmp(entry->name, base))
632 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
633 if (entry->flag & REF_BROKEN)
634 return 0; /* ignore dangling symref */
635 if (!has_sha1_file(entry->sha1)) {
636 error("%s does not point to a valid object!", entry->name);
641 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
644 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
647 struct ref_filter *filter = (struct ref_filter *)data;
648 if (fnmatch(filter->pattern, ref, 0))
650 return filter->fn(ref, sha, flags, filter->cb_data);
653 int peel_ref(const char *ref, unsigned char *sha1)
656 unsigned char base[20];
659 if (current_ref && (current_ref->name == ref
660 || !strcmp(current_ref->name, ref))) {
661 if (current_ref->flag & REF_KNOWS_PEELED) {
662 hashcpy(sha1, current_ref->peeled);
665 hashcpy(base, current_ref->sha1);
669 if (!resolve_ref(ref, base, 1, &flag))
672 if ((flag & REF_ISPACKED)) {
673 struct ref_list *list = get_packed_refs(NULL);
676 if (!strcmp(list->name, ref)) {
677 if (list->flag & REF_KNOWS_PEELED) {
678 hashcpy(sha1, list->peeled);
681 /* older pack-refs did not leave peeled ones */
689 o = parse_object(base);
690 if (o && o->type == OBJ_TAG) {
691 o = deref_tag(o, ref, 0);
693 hashcpy(sha1, o->sha1);
700 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
701 int trim, int flags, void *cb_data)
704 struct ref_list *packed = get_packed_refs(submodule);
705 struct ref_list *loose = get_loose_refs(submodule);
707 struct ref_list *extra;
709 for (extra = extra_refs; extra; extra = extra->next)
710 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
712 while (packed && loose) {
713 struct ref_list *entry;
714 int cmp = strcmp(packed->name, loose->name);
716 packed = packed->next;
724 packed = packed->next;
726 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
731 for (packed = packed ? packed : loose; packed; packed = packed->next) {
732 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
743 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
745 unsigned char sha1[20];
749 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
750 return fn("HEAD", sha1, 0, cb_data);
755 if (resolve_ref("HEAD", sha1, 1, &flag))
756 return fn("HEAD", sha1, flag, cb_data);
761 int head_ref(each_ref_fn fn, void *cb_data)
763 return do_head_ref(NULL, fn, cb_data);
766 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
768 return do_head_ref(submodule, fn, cb_data);
771 int for_each_ref(each_ref_fn fn, void *cb_data)
773 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
776 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
778 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
781 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
783 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
786 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
787 each_ref_fn fn, void *cb_data)
789 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
792 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
794 return for_each_ref_in("refs/tags/", fn, cb_data);
797 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
799 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
802 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
804 return for_each_ref_in("refs/heads/", fn, cb_data);
807 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
809 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
812 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
814 return for_each_ref_in("refs/remotes/", fn, cb_data);
817 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
819 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
822 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
824 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
827 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
829 struct strbuf buf = STRBUF_INIT;
831 unsigned char sha1[20];
834 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
835 if (resolve_ref(buf.buf, sha1, 1, &flag))
836 ret = fn(buf.buf, sha1, flag, cb_data);
837 strbuf_release(&buf);
842 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
844 struct strbuf buf = STRBUF_INIT;
846 strbuf_addf(&buf, "%srefs/", get_git_namespace());
847 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
848 strbuf_release(&buf);
852 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
853 const char *prefix, void *cb_data)
855 struct strbuf real_pattern = STRBUF_INIT;
856 struct ref_filter filter;
859 if (!prefix && prefixcmp(pattern, "refs/"))
860 strbuf_addstr(&real_pattern, "refs/");
862 strbuf_addstr(&real_pattern, prefix);
863 strbuf_addstr(&real_pattern, pattern);
865 if (!has_glob_specials(pattern)) {
866 /* Append implied '/' '*' if not present. */
867 if (real_pattern.buf[real_pattern.len - 1] != '/')
868 strbuf_addch(&real_pattern, '/');
869 /* No need to check for '*', there is none. */
870 strbuf_addch(&real_pattern, '*');
873 filter.pattern = real_pattern.buf;
875 filter.cb_data = cb_data;
876 ret = for_each_ref(filter_refs, &filter);
878 strbuf_release(&real_pattern);
882 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
884 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
887 int for_each_rawref(each_ref_fn fn, void *cb_data)
889 return do_for_each_ref(NULL, "", fn, 0,
890 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
894 * Make sure "ref" is something reasonable to have under ".git/refs/";
895 * We do not like it if:
897 * - any path component of it begins with ".", or
898 * - it has double dots "..", or
899 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
900 * - it ends with a "/".
901 * - it ends with ".lock"
902 * - it contains a "\" (backslash)
905 static inline int bad_ref_char(int ch)
907 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
908 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
910 /* 2.13 Pattern Matching Notation */
911 if (ch == '?' || ch == '[') /* Unsupported */
913 if (ch == '*') /* Supported at the end */
918 int check_ref_format(const char *ref)
920 int ch, level, bad_type, last;
921 int ret = CHECK_REF_FORMAT_OK;
922 const char *cp = ref;
926 while ((ch = *cp++) == '/')
927 ; /* tolerate duplicated slashes */
929 /* should not end with slashes */
930 return CHECK_REF_FORMAT_ERROR;
932 /* we are at the beginning of the path component */
934 return CHECK_REF_FORMAT_ERROR;
935 bad_type = bad_ref_char(ch);
937 if (bad_type == 2 && (!*cp || *cp == '/') &&
938 ret == CHECK_REF_FORMAT_OK)
939 ret = CHECK_REF_FORMAT_WILDCARD;
941 return CHECK_REF_FORMAT_ERROR;
945 /* scan the rest of the path component */
946 while ((ch = *cp++) != 0) {
947 bad_type = bad_ref_char(ch);
949 return CHECK_REF_FORMAT_ERROR;
952 if (last == '.' && ch == '.')
953 return CHECK_REF_FORMAT_ERROR;
954 if (last == '@' && ch == '{')
955 return CHECK_REF_FORMAT_ERROR;
960 if (ref <= cp - 2 && cp[-2] == '.')
961 return CHECK_REF_FORMAT_ERROR;
963 return CHECK_REF_FORMAT_ONELEVEL;
964 if (has_extension(ref, ".lock"))
965 return CHECK_REF_FORMAT_ERROR;
971 const char *prettify_refname(const char *name)
974 !prefixcmp(name, "refs/heads/") ? 11 :
975 !prefixcmp(name, "refs/tags/") ? 10 :
976 !prefixcmp(name, "refs/remotes/") ? 13 :
980 const char *ref_rev_parse_rules[] = {
986 "refs/remotes/%.*s/HEAD",
990 const char *ref_fetch_rules[] = {
997 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1000 const int abbrev_name_len = strlen(abbrev_name);
1002 for (p = rules; *p; p++) {
1003 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1011 static struct ref_lock *verify_lock(struct ref_lock *lock,
1012 const unsigned char *old_sha1, int mustexist)
1014 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1015 error("Can't verify ref %s", lock->ref_name);
1019 if (hashcmp(lock->old_sha1, old_sha1)) {
1020 error("Ref %s is at %s but expected %s", lock->ref_name,
1021 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1028 static int remove_empty_directories(const char *file)
1030 /* we want to create a file but there is a directory there;
1031 * if that is an empty directory (or a directory that contains
1032 * only empty directories), remove them.
1037 strbuf_init(&path, 20);
1038 strbuf_addstr(&path, file);
1040 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1042 strbuf_release(&path);
1047 static int is_refname_available(const char *ref, const char *oldref,
1048 struct ref_list *list, int quiet)
1050 int namlen = strlen(ref); /* e.g. 'foo/bar' */
1052 /* list->name could be 'foo' or 'foo/bar/baz' */
1053 if (!oldref || strcmp(oldref, list->name)) {
1054 int len = strlen(list->name);
1055 int cmplen = (namlen < len) ? namlen : len;
1056 const char *lead = (namlen < len) ? list->name : ref;
1057 if (!strncmp(ref, list->name, cmplen) &&
1058 lead[cmplen] == '/') {
1060 error("'%s' exists; cannot create '%s'",
1070 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1073 const char *orig_ref = ref;
1074 struct ref_lock *lock;
1077 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1080 lock = xcalloc(1, sizeof(struct ref_lock));
1083 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1084 if (!ref && errno == EISDIR) {
1085 /* we are trying to lock foo but we used to
1086 * have foo/bar which now does not exist;
1087 * it is normal for the empty directory 'foo'
1090 ref_file = git_path("%s", orig_ref);
1091 if (remove_empty_directories(ref_file)) {
1093 error("there are still refs under '%s'", orig_ref);
1096 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1102 error("unable to resolve reference %s: %s",
1103 orig_ref, strerror(errno));
1106 missing = is_null_sha1(lock->old_sha1);
1107 /* When the ref did not exist and we are creating it,
1108 * make sure there is no existing ref that is packed
1109 * whose name begins with our refname, nor a ref whose
1110 * name is a proper prefix of our refname.
1113 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1114 last_errno = ENOTDIR;
1118 lock->lk = xcalloc(1, sizeof(struct lock_file));
1120 lflags = LOCK_DIE_ON_ERROR;
1121 if (flags & REF_NODEREF) {
1123 lflags |= LOCK_NODEREF;
1125 lock->ref_name = xstrdup(ref);
1126 lock->orig_ref_name = xstrdup(orig_ref);
1127 ref_file = git_path("%s", ref);
1129 lock->force_write = 1;
1130 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1131 lock->force_write = 1;
1133 if (safe_create_leading_directories(ref_file)) {
1135 error("unable to create directory for %s", ref_file);
1139 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1140 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1148 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1150 char refpath[PATH_MAX];
1151 if (check_ref_format(ref))
1153 strcpy(refpath, mkpath("refs/%s", ref));
1154 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1157 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1159 switch (check_ref_format(ref)) {
1163 case CHECK_REF_FORMAT_ONELEVEL:
1164 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1168 static struct lock_file packlock;
1170 static int repack_without_ref(const char *refname)
1172 struct ref_list *list, *packed_ref_list;
1176 packed_ref_list = get_packed_refs(NULL);
1177 for (list = packed_ref_list; list; list = list->next) {
1178 if (!strcmp(refname, list->name)) {
1185 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1187 unable_to_lock_error(git_path("packed-refs"), errno);
1188 return error("cannot delete '%s' from packed refs", refname);
1191 for (list = packed_ref_list; list; list = list->next) {
1192 char line[PATH_MAX + 100];
1195 if (!strcmp(refname, list->name))
1197 len = snprintf(line, sizeof(line), "%s %s\n",
1198 sha1_to_hex(list->sha1), list->name);
1199 /* this should not happen but just being defensive */
1200 if (len > sizeof(line))
1201 die("too long a refname '%s'", list->name);
1202 write_or_die(fd, line, len);
1204 return commit_lock_file(&packlock);
1207 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1209 struct ref_lock *lock;
1210 int err, i = 0, ret = 0, flag = 0;
1212 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1215 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1219 if (!(delopt & REF_NODEREF)) {
1220 i = strlen(lock->lk->filename) - 5; /* .lock */
1221 lock->lk->filename[i] = 0;
1222 path = lock->lk->filename;
1224 path = git_path("%s", refname);
1226 err = unlink_or_warn(path);
1227 if (err && errno != ENOENT)
1230 if (!(delopt & REF_NODEREF))
1231 lock->lk->filename[i] = '.';
1233 /* removing the loose one could have resurrected an earlier
1234 * packed one. Also, if it was not loose we need to repack
1237 ret |= repack_without_ref(refname);
1239 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1240 invalidate_cached_refs();
1246 * People using contrib's git-new-workdir have .git/logs/refs ->
1247 * /some/other/path/.git/logs/refs, and that may live on another device.
1249 * IOW, to avoid cross device rename errors, the temporary renamed log must
1250 * live into logs/refs.
1252 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1254 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1256 static const char renamed_ref[] = "RENAMED-REF";
1257 unsigned char sha1[20], orig_sha1[20];
1258 int flag = 0, logmoved = 0;
1259 struct ref_lock *lock;
1260 struct stat loginfo;
1261 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1262 const char *symref = NULL;
1264 if (log && S_ISLNK(loginfo.st_mode))
1265 return error("reflog for %s is a symlink", oldref);
1267 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1268 if (flag & REF_ISSYMREF)
1269 return error("refname %s is a symbolic ref, renaming it is not supported",
1272 return error("refname %s not found", oldref);
1274 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1277 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1280 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1282 return error("unable to lock %s", renamed_ref);
1283 lock->force_write = 1;
1284 if (write_ref_sha1(lock, orig_sha1, logmsg))
1285 return error("unable to save current sha1 in %s", renamed_ref);
1287 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1288 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1289 oldref, strerror(errno));
1291 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1292 error("unable to delete old %s", oldref);
1296 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1297 if (errno==EISDIR) {
1298 if (remove_empty_directories(git_path("%s", newref))) {
1299 error("Directory not empty: %s", newref);
1303 error("unable to delete existing %s", newref);
1308 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1309 error("unable to create directory for %s", newref);
1314 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1315 if (errno==EISDIR || errno==ENOTDIR) {
1317 * rename(a, b) when b is an existing
1318 * directory ought to result in ISDIR, but
1319 * Solaris 5.8 gives ENOTDIR. Sheesh.
1321 if (remove_empty_directories(git_path("logs/%s", newref))) {
1322 error("Directory not empty: logs/%s", newref);
1327 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1328 newref, strerror(errno));
1334 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1336 error("unable to lock %s for update", newref);
1339 lock->force_write = 1;
1340 hashcpy(lock->old_sha1, orig_sha1);
1341 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1342 error("unable to write current sha1 into %s", newref);
1349 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1351 error("unable to lock %s for rollback", oldref);
1355 lock->force_write = 1;
1356 flag = log_all_ref_updates;
1357 log_all_ref_updates = 0;
1358 if (write_ref_sha1(lock, orig_sha1, NULL))
1359 error("unable to write current sha1 into %s", oldref);
1360 log_all_ref_updates = flag;
1363 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1364 error("unable to restore logfile %s from %s: %s",
1365 oldref, newref, strerror(errno));
1366 if (!logmoved && log &&
1367 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1368 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1369 oldref, strerror(errno));
1374 int close_ref(struct ref_lock *lock)
1376 if (close_lock_file(lock->lk))
1382 int commit_ref(struct ref_lock *lock)
1384 if (commit_lock_file(lock->lk))
1390 void unlock_ref(struct ref_lock *lock)
1392 /* Do not free lock->lk -- atexit() still looks at them */
1394 rollback_lock_file(lock->lk);
1395 free(lock->ref_name);
1396 free(lock->orig_ref_name);
1401 * copy the reflog message msg to buf, which has been allocated sufficiently
1402 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1403 * because reflog file is one line per entry.
1405 static int copy_msg(char *buf, const char *msg)
1412 while ((c = *msg++)) {
1413 if (wasspace && isspace(c))
1415 wasspace = isspace(c);
1420 while (buf < cp && isspace(cp[-1]))
1426 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1428 int logfd, oflags = O_APPEND | O_WRONLY;
1430 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1431 if (log_all_ref_updates &&
1432 (!prefixcmp(ref_name, "refs/heads/") ||
1433 !prefixcmp(ref_name, "refs/remotes/") ||
1434 !prefixcmp(ref_name, "refs/notes/") ||
1435 !strcmp(ref_name, "HEAD"))) {
1436 if (safe_create_leading_directories(logfile) < 0)
1437 return error("unable to create directory for %s",
1442 logfd = open(logfile, oflags, 0666);
1444 if (!(oflags & O_CREAT) && errno == ENOENT)
1447 if ((oflags & O_CREAT) && errno == EISDIR) {
1448 if (remove_empty_directories(logfile)) {
1449 return error("There are still logs under '%s'",
1452 logfd = open(logfile, oflags, 0666);
1456 return error("Unable to append to %s: %s",
1457 logfile, strerror(errno));
1460 adjust_shared_perm(logfile);
1465 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1466 const unsigned char *new_sha1, const char *msg)
1468 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1469 unsigned maxlen, len;
1471 char log_file[PATH_MAX];
1473 const char *committer;
1475 if (log_all_ref_updates < 0)
1476 log_all_ref_updates = !is_bare_repository();
1478 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1482 logfd = open(log_file, oflags);
1485 msglen = msg ? strlen(msg) : 0;
1486 committer = git_committer_info(0);
1487 maxlen = strlen(committer) + msglen + 100;
1488 logrec = xmalloc(maxlen);
1489 len = sprintf(logrec, "%s %s %s\n",
1490 sha1_to_hex(old_sha1),
1491 sha1_to_hex(new_sha1),
1494 len += copy_msg(logrec + len - 1, msg) - 1;
1495 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1497 if (close(logfd) != 0 || written != len)
1498 return error("Unable to append to %s", log_file);
1502 static int is_branch(const char *refname)
1504 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1507 int write_ref_sha1(struct ref_lock *lock,
1508 const unsigned char *sha1, const char *logmsg)
1510 static char term = '\n';
1515 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1519 o = parse_object(sha1);
1521 error("Trying to write ref %s with nonexistent object %s",
1522 lock->ref_name, sha1_to_hex(sha1));
1526 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1527 error("Trying to write non-commit object %s to branch %s",
1528 sha1_to_hex(sha1), lock->ref_name);
1532 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1533 write_in_full(lock->lock_fd, &term, 1) != 1
1534 || close_ref(lock) < 0) {
1535 error("Couldn't write %s", lock->lk->filename);
1539 invalidate_cached_refs();
1540 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1541 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1542 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1546 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1548 * Special hack: If a branch is updated directly and HEAD
1549 * points to it (may happen on the remote side of a push
1550 * for example) then logically the HEAD reflog should be
1552 * A generic solution implies reverse symref information,
1553 * but finding all symrefs pointing to the given branch
1554 * would be rather costly for this rare event (the direct
1555 * update of a branch) to be worth it. So let's cheat and
1556 * check with HEAD only which should cover 99% of all usage
1557 * scenarios (even 100% of the default ones).
1559 unsigned char head_sha1[20];
1561 const char *head_ref;
1562 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1563 if (head_ref && (head_flag & REF_ISSYMREF) &&
1564 !strcmp(head_ref, lock->ref_name))
1565 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1567 if (commit_ref(lock)) {
1568 error("Couldn't set %s", lock->ref_name);
1576 int create_symref(const char *ref_target, const char *refs_heads_master,
1579 const char *lockpath;
1581 int fd, len, written;
1582 char *git_HEAD = git_pathdup("%s", ref_target);
1583 unsigned char old_sha1[20], new_sha1[20];
1585 if (logmsg && read_ref(ref_target, old_sha1))
1588 if (safe_create_leading_directories(git_HEAD) < 0)
1589 return error("unable to create directory for %s", git_HEAD);
1591 #ifndef NO_SYMLINK_HEAD
1592 if (prefer_symlink_refs) {
1594 if (!symlink(refs_heads_master, git_HEAD))
1596 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1600 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1601 if (sizeof(ref) <= len) {
1602 error("refname too long: %s", refs_heads_master);
1603 goto error_free_return;
1605 lockpath = mkpath("%s.lock", git_HEAD);
1606 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1608 error("Unable to open %s for writing", lockpath);
1609 goto error_free_return;
1611 written = write_in_full(fd, ref, len);
1612 if (close(fd) != 0 || written != len) {
1613 error("Unable to write to %s", lockpath);
1614 goto error_unlink_return;
1616 if (rename(lockpath, git_HEAD) < 0) {
1617 error("Unable to create %s", git_HEAD);
1618 goto error_unlink_return;
1620 if (adjust_shared_perm(git_HEAD)) {
1621 error("Unable to fix permissions on %s", lockpath);
1622 error_unlink_return:
1623 unlink_or_warn(lockpath);
1629 #ifndef NO_SYMLINK_HEAD
1632 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1633 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1639 static char *ref_msg(const char *line, const char *endp)
1643 ep = memchr(line, '\n', endp - line);
1646 return xmemdupz(line, ep - line);
1649 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)
1651 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1653 int logfd, tz, reccnt = 0;
1656 unsigned char logged_sha1[20];
1660 logfile = git_path("logs/%s", ref);
1661 logfd = open(logfile, O_RDONLY, 0);
1663 die_errno("Unable to read log '%s'", logfile);
1666 die("Log %s is empty.", logfile);
1667 mapsz = xsize_t(st.st_size);
1668 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1669 logdata = log_mapped;
1673 rec = logend = logdata + st.st_size;
1674 while (logdata < rec) {
1676 if (logdata < rec && *(rec-1) == '\n')
1679 while (logdata < rec && *(rec-1) != '\n') {
1685 die("Log %s is corrupt.", logfile);
1686 date = strtoul(lastgt + 1, &tz_c, 10);
1687 if (date <= at_time || cnt == 0) {
1688 tz = strtoul(tz_c, NULL, 10);
1690 *msg = ref_msg(rec, logend);
1692 *cutoff_time = date;
1696 *cutoff_cnt = reccnt - 1;
1698 if (get_sha1_hex(lastrec, logged_sha1))
1699 die("Log %s is corrupt.", logfile);
1700 if (get_sha1_hex(rec + 41, sha1))
1701 die("Log %s is corrupt.", logfile);
1702 if (hashcmp(logged_sha1, sha1)) {
1703 warning("Log %s has gap after %s.",
1704 logfile, show_date(date, tz, DATE_RFC2822));
1707 else if (date == at_time) {
1708 if (get_sha1_hex(rec + 41, sha1))
1709 die("Log %s is corrupt.", logfile);
1712 if (get_sha1_hex(rec + 41, logged_sha1))
1713 die("Log %s is corrupt.", logfile);
1714 if (hashcmp(logged_sha1, sha1)) {
1715 warning("Log %s unexpectedly ended on %s.",
1716 logfile, show_date(date, tz, DATE_RFC2822));
1719 munmap(log_mapped, mapsz);
1728 while (rec < logend && *rec != '>' && *rec != '\n')
1730 if (rec == logend || *rec == '\n')
1731 die("Log %s is corrupt.", logfile);
1732 date = strtoul(rec + 1, &tz_c, 10);
1733 tz = strtoul(tz_c, NULL, 10);
1734 if (get_sha1_hex(logdata, sha1))
1735 die("Log %s is corrupt.", logfile);
1736 if (is_null_sha1(sha1)) {
1737 if (get_sha1_hex(logdata + 41, sha1))
1738 die("Log %s is corrupt.", logfile);
1741 *msg = ref_msg(logdata, logend);
1742 munmap(log_mapped, mapsz);
1745 *cutoff_time = date;
1749 *cutoff_cnt = reccnt;
1753 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1755 const char *logfile;
1757 struct strbuf sb = STRBUF_INIT;
1760 logfile = git_path("logs/%s", ref);
1761 logfp = fopen(logfile, "r");
1766 struct stat statbuf;
1767 if (fstat(fileno(logfp), &statbuf) ||
1768 statbuf.st_size < ofs ||
1769 fseek(logfp, -ofs, SEEK_END) ||
1770 strbuf_getwholeline(&sb, logfp, '\n')) {
1772 strbuf_release(&sb);
1777 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1778 unsigned char osha1[20], nsha1[20];
1779 char *email_end, *message;
1780 unsigned long timestamp;
1783 /* old SP new SP name <email> SP time TAB msg LF */
1784 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1785 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1786 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1787 !(email_end = strchr(sb.buf + 82, '>')) ||
1788 email_end[1] != ' ' ||
1789 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1790 !message || message[0] != ' ' ||
1791 (message[1] != '+' && message[1] != '-') ||
1792 !isdigit(message[2]) || !isdigit(message[3]) ||
1793 !isdigit(message[4]) || !isdigit(message[5]))
1794 continue; /* corrupt? */
1795 email_end[1] = '\0';
1796 tz = strtol(message + 1, NULL, 10);
1797 if (message[6] != '\t')
1801 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1807 strbuf_release(&sb);
1811 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1813 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1816 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1818 DIR *dir = opendir(git_path("logs/%s", base));
1823 int baselen = strlen(base);
1824 char *log = xmalloc(baselen + 257);
1826 memcpy(log, base, baselen);
1827 if (baselen && base[baselen-1] != '/')
1828 log[baselen++] = '/';
1830 while ((de = readdir(dir)) != NULL) {
1834 if (de->d_name[0] == '.')
1836 namelen = strlen(de->d_name);
1839 if (has_extension(de->d_name, ".lock"))
1841 memcpy(log + baselen, de->d_name, namelen+1);
1842 if (stat(git_path("logs/%s", log), &st) < 0)
1844 if (S_ISDIR(st.st_mode)) {
1845 retval = do_for_each_reflog(log, fn, cb_data);
1847 unsigned char sha1[20];
1848 if (!resolve_ref(log, sha1, 0, NULL))
1849 retval = error("bad ref for %s", log);
1851 retval = fn(log, sha1, 0, cb_data);
1864 int for_each_reflog(each_ref_fn fn, void *cb_data)
1866 return do_for_each_reflog("", fn, cb_data);
1869 int update_ref(const char *action, const char *refname,
1870 const unsigned char *sha1, const unsigned char *oldval,
1871 int flags, enum action_on_err onerr)
1873 static struct ref_lock *lock;
1874 lock = lock_any_ref_for_update(refname, oldval, flags);
1876 const char *str = "Cannot lock the ref '%s'.";
1878 case MSG_ON_ERR: error(str, refname); break;
1879 case DIE_ON_ERR: die(str, refname); break;
1880 case QUIET_ON_ERR: break;
1884 if (write_ref_sha1(lock, sha1, action) < 0) {
1885 const char *str = "Cannot update the ref '%s'.";
1887 case MSG_ON_ERR: error(str, refname); break;
1888 case DIE_ON_ERR: die(str, refname); break;
1889 case QUIET_ON_ERR: break;
1896 int ref_exists(char *refname)
1898 unsigned char sha1[20];
1899 return !!resolve_ref(refname, sha1, 1, NULL);
1902 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1904 for ( ; list; list = list->next)
1905 if (!strcmp(list->name, name))
1906 return (struct ref *)list;
1911 * generate a format suitable for scanf from a ref_rev_parse_rules
1912 * rule, that is replace the "%.*s" spec with a "%s" spec
1914 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1918 spec = strstr(rule, "%.*s");
1919 if (!spec || strstr(spec + 4, "%.*s"))
1920 die("invalid rule in ref_rev_parse_rules: %s", rule);
1922 /* copy all until spec */
1923 strncpy(scanf_fmt, rule, spec - rule);
1924 scanf_fmt[spec - rule] = '\0';
1926 strcat(scanf_fmt, "%s");
1927 /* copy remaining rule */
1928 strcat(scanf_fmt, spec + 4);
1933 char *shorten_unambiguous_ref(const char *ref, int strict)
1936 static char **scanf_fmts;
1937 static int nr_rules;
1940 /* pre generate scanf formats from ref_rev_parse_rules[] */
1942 size_t total_len = 0;
1944 /* the rule list is NULL terminated, count them first */
1945 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1946 /* no +1 because strlen("%s") < strlen("%.*s") */
1947 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1949 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1952 for (i = 0; i < nr_rules; i++) {
1953 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1955 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1956 total_len += strlen(ref_rev_parse_rules[i]);
1960 /* bail out if there are no rules */
1962 return xstrdup(ref);
1964 /* buffer for scanf result, at most ref must fit */
1965 short_name = xstrdup(ref);
1967 /* skip first rule, it will always match */
1968 for (i = nr_rules - 1; i > 0 ; --i) {
1970 int rules_to_fail = i;
1973 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1976 short_name_len = strlen(short_name);
1979 * in strict mode, all (except the matched one) rules
1980 * must fail to resolve to a valid non-ambiguous ref
1983 rules_to_fail = nr_rules;
1986 * check if the short name resolves to a valid ref,
1987 * but use only rules prior to the matched one
1989 for (j = 0; j < rules_to_fail; j++) {
1990 const char *rule = ref_rev_parse_rules[j];
1991 unsigned char short_objectname[20];
1992 char refname[PATH_MAX];
1994 /* skip matched rule */
1999 * the short name is ambiguous, if it resolves
2000 * (with this previous rule) to a valid ref
2001 * read_ref() returns 0 on success
2003 mksnpath(refname, sizeof(refname),
2004 rule, short_name_len, short_name);
2005 if (!read_ref(refname, short_objectname))
2010 * short name is non-ambiguous if all previous rules
2011 * haven't resolved to a valid ref
2013 if (j == rules_to_fail)
2018 return xstrdup(ref);