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 {
158 struct ref_list *loose;
159 struct ref_list *packed;
160 } cached_refs, submodule_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) {
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];
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 */
206 name = parse_ref_line(refline, sha1);
208 list = add_ref(name, sha1, flag, list, &last);
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);
232 static struct ref_list *get_packed_refs(const char *submodule)
234 const char *packed_refs_file;
235 struct cached_refs *refs;
238 packed_refs_file = git_path_submodule(submodule, "packed-refs");
239 refs = &submodule_refs;
240 free_ref_list(refs->packed);
242 packed_refs_file = git_path("packed-refs");
246 if (!refs->did_packed || submodule) {
247 FILE *f = fopen(packed_refs_file, "r");
250 read_packed_refs(f, refs);
253 refs->did_packed = 1;
258 static struct ref_list *get_ref_dir(const char *submodule, const char *base,
259 struct ref_list *list)
265 path = git_path_submodule(submodule, "%s", base);
267 path = git_path("%s", base);
274 int baselen = strlen(base);
275 char *ref = xmalloc(baselen + 257);
277 memcpy(ref, base, baselen);
278 if (baselen && base[baselen-1] != '/')
279 ref[baselen++] = '/';
281 while ((de = readdir(dir)) != NULL) {
282 unsigned char sha1[20];
288 if (de->d_name[0] == '.')
290 namelen = strlen(de->d_name);
293 if (has_extension(de->d_name, ".lock"))
295 memcpy(ref + baselen, de->d_name, namelen+1);
297 ? git_path_submodule(submodule, "%s", ref)
298 : git_path("%s", ref);
299 if (stat(refdir, &st) < 0)
301 if (S_ISDIR(st.st_mode)) {
302 list = get_ref_dir(submodule, ref, list);
308 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
313 if (!resolve_ref(ref, sha1, 1, &flag)) {
317 list = add_ref(ref, sha1, flag, list, NULL);
322 return sort_ref_list(list);
325 struct warn_if_dangling_data {
331 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
332 int flags, void *cb_data)
334 struct warn_if_dangling_data *d = cb_data;
335 const char *resolves_to;
336 unsigned char junk[20];
338 if (!(flags & REF_ISSYMREF))
341 resolves_to = resolve_ref(refname, junk, 0, NULL);
342 if (!resolves_to || strcmp(resolves_to, d->refname))
345 fprintf(d->fp, d->msg_fmt, refname);
349 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
351 struct warn_if_dangling_data data;
354 data.refname = refname;
355 data.msg_fmt = msg_fmt;
356 for_each_rawref(warn_if_dangling_symref, &data);
359 static struct ref_list *get_loose_refs(const char *submodule)
362 free_ref_list(submodule_refs.loose);
363 submodule_refs.loose = get_ref_dir(submodule, "refs", NULL);
364 return submodule_refs.loose;
367 if (!cached_refs.did_loose) {
368 cached_refs.loose = get_ref_dir(NULL, "refs", NULL);
369 cached_refs.did_loose = 1;
371 return cached_refs.loose;
374 /* We allow "recursive" symbolic refs. Only within reason, though */
376 #define MAXREFLEN (1024)
378 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
381 struct cached_refs refs;
382 struct ref_list *ref;
385 strcpy(name + pathlen, "packed-refs");
386 f = fopen(name, "r");
389 read_packed_refs(f, &refs);
394 if (!strcmp(ref->name, refname)) {
396 memcpy(result, ref->sha1, 20);
401 free_ref_list(refs.packed);
405 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
407 int fd, len = strlen(refname);
408 char buffer[128], *p;
410 if (recursion > MAXDEPTH || len > MAXREFLEN)
412 memcpy(name + pathlen, refname, len+1);
413 fd = open(name, O_RDONLY);
415 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
417 len = read(fd, buffer, sizeof(buffer)-1);
421 while (len && isspace(buffer[len-1]))
425 /* Was it a detached head or an old-fashioned symlink? */
426 if (!get_sha1_hex(buffer, result))
430 if (strncmp(buffer, "ref:", 4))
436 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
439 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
441 int len = strlen(path), retval;
445 while (len && path[len-1] == '/')
449 gitdir = xmalloc(len + MAXREFLEN + 8);
450 memcpy(gitdir, path, len);
451 memcpy(gitdir + len, "/.git", 6);
454 tmp = read_gitfile(gitdir);
458 gitdir = xmalloc(len + MAXREFLEN + 3);
459 memcpy(gitdir, tmp, len);
462 gitdir[++len] = '\0';
463 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
469 * If the "reading" argument is set, this function finds out what _object_
470 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
471 * has to exist, and if it is symbolic, it has to point at an existing ref,
472 * because the "read" goes through the symref to the ref it points at.
474 * The access that is not "reading" may often be "writing", but does not
475 * have to; it can be merely checking _where it leads to_. If it is a
476 * prelude to "writing" to the ref, a write to a symref that points at
477 * yet-to-be-born ref will create the real ref pointed by the symref.
478 * reading=0 allows the caller to check where such a symref leads to.
480 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
482 int depth = MAXDEPTH;
485 static char ref_buffer[256];
499 git_snpath(path, sizeof(path), "%s", ref);
500 /* Special case: non-existing file. */
501 if (lstat(path, &st) < 0) {
502 struct ref_list *list = get_packed_refs(NULL);
504 if (!strcmp(ref, list->name)) {
505 hashcpy(sha1, list->sha1);
507 *flag |= REF_ISPACKED;
512 if (reading || errno != ENOENT)
518 /* Follow "normalized" - ie "refs/.." symlinks by hand */
519 if (S_ISLNK(st.st_mode)) {
520 len = readlink(path, buffer, sizeof(buffer)-1);
524 if (!prefixcmp(buffer, "refs/") &&
525 !check_refname_format(buffer, 0)) {
526 strcpy(ref_buffer, buffer);
529 *flag |= REF_ISSYMREF;
534 /* Is it a directory? */
535 if (S_ISDIR(st.st_mode)) {
541 * Anything else, just open it and try to use it as
544 fd = open(path, O_RDONLY);
547 len = read_in_full(fd, buffer, sizeof(buffer)-1);
551 * Is it a symbolic ref?
553 if (len < 4 || memcmp("ref:", buffer, 4))
557 while (len && isspace(*buf))
559 while (len && isspace(buf[len-1]))
562 memcpy(ref_buffer, buf, len + 1);
565 *flag |= REF_ISSYMREF;
567 if (len < 40 || get_sha1_hex(buffer, sha1))
572 /* The argument to filter_refs */
579 int read_ref(const char *ref, unsigned char *sha1)
581 if (resolve_ref(ref, sha1, 1, NULL))
586 #define DO_FOR_EACH_INCLUDE_BROKEN 01
587 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
588 int flags, void *cb_data, struct ref_list *entry)
590 if (prefixcmp(entry->name, base))
593 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
594 if (entry->flag & REF_BROKEN)
595 return 0; /* ignore dangling symref */
596 if (!has_sha1_file(entry->sha1)) {
597 error("%s does not point to a valid object!", entry->name);
602 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
605 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
608 struct ref_filter *filter = (struct ref_filter *)data;
609 if (fnmatch(filter->pattern, ref, 0))
611 return filter->fn(ref, sha, flags, filter->cb_data);
614 int peel_ref(const char *ref, unsigned char *sha1)
617 unsigned char base[20];
620 if (current_ref && (current_ref->name == ref
621 || !strcmp(current_ref->name, ref))) {
622 if (current_ref->flag & REF_KNOWS_PEELED) {
623 hashcpy(sha1, current_ref->peeled);
626 hashcpy(base, current_ref->sha1);
630 if (!resolve_ref(ref, base, 1, &flag))
633 if ((flag & REF_ISPACKED)) {
634 struct ref_list *list = get_packed_refs(NULL);
637 if (!strcmp(list->name, ref)) {
638 if (list->flag & REF_KNOWS_PEELED) {
639 hashcpy(sha1, list->peeled);
642 /* older pack-refs did not leave peeled ones */
650 o = parse_object(base);
651 if (o && o->type == OBJ_TAG) {
652 o = deref_tag(o, ref, 0);
654 hashcpy(sha1, o->sha1);
661 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
662 int trim, int flags, void *cb_data)
665 struct ref_list *packed = get_packed_refs(submodule);
666 struct ref_list *loose = get_loose_refs(submodule);
668 struct ref_list *extra;
670 for (extra = extra_refs; extra; extra = extra->next)
671 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
673 while (packed && loose) {
674 struct ref_list *entry;
675 int cmp = strcmp(packed->name, loose->name);
677 packed = packed->next;
685 packed = packed->next;
687 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
692 for (packed = packed ? packed : loose; packed; packed = packed->next) {
693 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
704 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
706 unsigned char sha1[20];
710 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
711 return fn("HEAD", sha1, 0, cb_data);
716 if (resolve_ref("HEAD", sha1, 1, &flag))
717 return fn("HEAD", sha1, flag, cb_data);
722 int head_ref(each_ref_fn fn, void *cb_data)
724 return do_head_ref(NULL, fn, cb_data);
727 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
729 return do_head_ref(submodule, fn, cb_data);
732 int for_each_ref(each_ref_fn fn, void *cb_data)
734 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
737 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
739 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
742 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
744 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
747 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
748 each_ref_fn fn, void *cb_data)
750 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
753 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
755 return for_each_ref_in("refs/tags/", fn, cb_data);
758 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
760 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
763 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
765 return for_each_ref_in("refs/heads/", fn, cb_data);
768 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
770 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
773 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
775 return for_each_ref_in("refs/remotes/", fn, cb_data);
778 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
780 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
783 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
785 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
788 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
790 struct strbuf buf = STRBUF_INIT;
792 unsigned char sha1[20];
795 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
796 if (resolve_ref(buf.buf, sha1, 1, &flag))
797 ret = fn(buf.buf, sha1, flag, cb_data);
798 strbuf_release(&buf);
803 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
805 struct strbuf buf = STRBUF_INIT;
807 strbuf_addf(&buf, "%srefs/", get_git_namespace());
808 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
809 strbuf_release(&buf);
813 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
814 const char *prefix, void *cb_data)
816 struct strbuf real_pattern = STRBUF_INIT;
817 struct ref_filter filter;
820 if (!prefix && prefixcmp(pattern, "refs/"))
821 strbuf_addstr(&real_pattern, "refs/");
823 strbuf_addstr(&real_pattern, prefix);
824 strbuf_addstr(&real_pattern, pattern);
826 if (!has_glob_specials(pattern)) {
827 /* Append implied '/' '*' if not present. */
828 if (real_pattern.buf[real_pattern.len - 1] != '/')
829 strbuf_addch(&real_pattern, '/');
830 /* No need to check for '*', there is none. */
831 strbuf_addch(&real_pattern, '*');
834 filter.pattern = real_pattern.buf;
836 filter.cb_data = cb_data;
837 ret = for_each_ref(filter_refs, &filter);
839 strbuf_release(&real_pattern);
843 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
845 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
848 int for_each_rawref(each_ref_fn fn, void *cb_data)
850 return do_for_each_ref(NULL, "", fn, 0,
851 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
855 * Make sure "ref" is something reasonable to have under ".git/refs/";
856 * We do not like it if:
858 * - any path component of it begins with ".", or
859 * - it has double dots "..", or
860 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
861 * - it ends with a "/".
862 * - it ends with ".lock"
863 * - it contains a "\" (backslash)
866 /* Return true iff ch is not allowed in reference names. */
867 static inline int bad_ref_char(int ch)
869 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
870 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
872 /* 2.13 Pattern Matching Notation */
873 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
879 * Try to read one refname component from the front of ref. Return
880 * the length of the component found, or -1 if the component is not
883 static int check_refname_component(const char *ref)
888 for (cp = ref; ; cp++) {
890 if (ch == '\0' || ch == '/')
892 if (bad_ref_char(ch))
893 return -1; /* Illegal character in refname. */
894 if (last == '.' && ch == '.')
895 return -1; /* Refname contains "..". */
896 if (last == '@' && ch == '{')
897 return -1; /* Refname contains "@{". */
901 return -1; /* Component has zero length. */
903 return -1; /* Component starts with '.'. */
904 if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
905 return -1; /* Refname ends with ".lock". */
909 int check_refname_format(const char *ref, int flags)
911 int component_len, component_count = 0;
914 /* We are at the start of a path component. */
915 component_len = check_refname_component(ref);
916 if (component_len < 0) {
917 if ((flags & REFNAME_REFSPEC_PATTERN) &&
919 (ref[1] == '\0' || ref[1] == '/')) {
920 /* Accept one wildcard as a full refname component. */
921 flags &= ~REFNAME_REFSPEC_PATTERN;
928 if (ref[component_len] == '\0')
930 /* Skip to next component. */
931 ref += component_len + 1;
934 if (ref[component_len - 1] == '.')
935 return -1; /* Refname ends with '.'. */
936 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
937 return -1; /* Refname has only one component. */
941 const char *prettify_refname(const char *name)
944 !prefixcmp(name, "refs/heads/") ? 11 :
945 !prefixcmp(name, "refs/tags/") ? 10 :
946 !prefixcmp(name, "refs/remotes/") ? 13 :
950 const char *ref_rev_parse_rules[] = {
956 "refs/remotes/%.*s/HEAD",
960 const char *ref_fetch_rules[] = {
967 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
970 const int abbrev_name_len = strlen(abbrev_name);
972 for (p = rules; *p; p++) {
973 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
981 static struct ref_lock *verify_lock(struct ref_lock *lock,
982 const unsigned char *old_sha1, int mustexist)
984 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
985 error("Can't verify ref %s", lock->ref_name);
989 if (hashcmp(lock->old_sha1, old_sha1)) {
990 error("Ref %s is at %s but expected %s", lock->ref_name,
991 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
998 static int remove_empty_directories(const char *file)
1000 /* we want to create a file but there is a directory there;
1001 * if that is an empty directory (or a directory that contains
1002 * only empty directories), remove them.
1007 strbuf_init(&path, 20);
1008 strbuf_addstr(&path, file);
1010 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1012 strbuf_release(&path);
1017 static int is_refname_available(const char *ref, const char *oldref,
1018 struct ref_list *list, int quiet)
1020 int namlen = strlen(ref); /* e.g. 'foo/bar' */
1022 /* list->name could be 'foo' or 'foo/bar/baz' */
1023 if (!oldref || strcmp(oldref, list->name)) {
1024 int len = strlen(list->name);
1025 int cmplen = (namlen < len) ? namlen : len;
1026 const char *lead = (namlen < len) ? list->name : ref;
1027 if (!strncmp(ref, list->name, cmplen) &&
1028 lead[cmplen] == '/') {
1030 error("'%s' exists; cannot create '%s'",
1040 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1043 const char *orig_ref = ref;
1044 struct ref_lock *lock;
1047 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1050 lock = xcalloc(1, sizeof(struct ref_lock));
1053 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1054 if (!ref && errno == EISDIR) {
1055 /* we are trying to lock foo but we used to
1056 * have foo/bar which now does not exist;
1057 * it is normal for the empty directory 'foo'
1060 ref_file = git_path("%s", orig_ref);
1061 if (remove_empty_directories(ref_file)) {
1063 error("there are still refs under '%s'", orig_ref);
1066 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1072 error("unable to resolve reference %s: %s",
1073 orig_ref, strerror(errno));
1076 missing = is_null_sha1(lock->old_sha1);
1077 /* When the ref did not exist and we are creating it,
1078 * make sure there is no existing ref that is packed
1079 * whose name begins with our refname, nor a ref whose
1080 * name is a proper prefix of our refname.
1083 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1084 last_errno = ENOTDIR;
1088 lock->lk = xcalloc(1, sizeof(struct lock_file));
1090 lflags = LOCK_DIE_ON_ERROR;
1091 if (flags & REF_NODEREF) {
1093 lflags |= LOCK_NODEREF;
1095 lock->ref_name = xstrdup(ref);
1096 lock->orig_ref_name = xstrdup(orig_ref);
1097 ref_file = git_path("%s", ref);
1099 lock->force_write = 1;
1100 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1101 lock->force_write = 1;
1103 if (safe_create_leading_directories(ref_file)) {
1105 error("unable to create directory for %s", ref_file);
1109 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1110 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1118 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1120 char refpath[PATH_MAX];
1121 if (check_refname_format(ref, 0))
1123 strcpy(refpath, mkpath("refs/%s", ref));
1124 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1127 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1129 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
1131 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1134 static struct lock_file packlock;
1136 static int repack_without_ref(const char *refname)
1138 struct ref_list *list, *packed_ref_list;
1142 packed_ref_list = get_packed_refs(NULL);
1143 for (list = packed_ref_list; list; list = list->next) {
1144 if (!strcmp(refname, list->name)) {
1151 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1153 unable_to_lock_error(git_path("packed-refs"), errno);
1154 return error("cannot delete '%s' from packed refs", refname);
1157 for (list = packed_ref_list; list; list = list->next) {
1158 char line[PATH_MAX + 100];
1161 if (!strcmp(refname, list->name))
1163 len = snprintf(line, sizeof(line), "%s %s\n",
1164 sha1_to_hex(list->sha1), list->name);
1165 /* this should not happen but just being defensive */
1166 if (len > sizeof(line))
1167 die("too long a refname '%s'", list->name);
1168 write_or_die(fd, line, len);
1170 return commit_lock_file(&packlock);
1173 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1175 struct ref_lock *lock;
1176 int err, i = 0, ret = 0, flag = 0;
1178 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1181 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1185 if (!(delopt & REF_NODEREF)) {
1186 i = strlen(lock->lk->filename) - 5; /* .lock */
1187 lock->lk->filename[i] = 0;
1188 path = lock->lk->filename;
1190 path = git_path("%s", refname);
1192 err = unlink_or_warn(path);
1193 if (err && errno != ENOENT)
1196 if (!(delopt & REF_NODEREF))
1197 lock->lk->filename[i] = '.';
1199 /* removing the loose one could have resurrected an earlier
1200 * packed one. Also, if it was not loose we need to repack
1203 ret |= repack_without_ref(refname);
1205 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1206 invalidate_cached_refs();
1212 * People using contrib's git-new-workdir have .git/logs/refs ->
1213 * /some/other/path/.git/logs/refs, and that may live on another device.
1215 * IOW, to avoid cross device rename errors, the temporary renamed log must
1216 * live into logs/refs.
1218 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1220 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1222 static const char renamed_ref[] = "RENAMED-REF";
1223 unsigned char sha1[20], orig_sha1[20];
1224 int flag = 0, logmoved = 0;
1225 struct ref_lock *lock;
1226 struct stat loginfo;
1227 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1228 const char *symref = NULL;
1230 if (log && S_ISLNK(loginfo.st_mode))
1231 return error("reflog for %s is a symlink", oldref);
1233 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1234 if (flag & REF_ISSYMREF)
1235 return error("refname %s is a symbolic ref, renaming it is not supported",
1238 return error("refname %s not found", oldref);
1240 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1243 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1246 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1248 return error("unable to lock %s", renamed_ref);
1249 lock->force_write = 1;
1250 if (write_ref_sha1(lock, orig_sha1, logmsg))
1251 return error("unable to save current sha1 in %s", renamed_ref);
1253 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1254 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1255 oldref, strerror(errno));
1257 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1258 error("unable to delete old %s", oldref);
1262 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1263 if (errno==EISDIR) {
1264 if (remove_empty_directories(git_path("%s", newref))) {
1265 error("Directory not empty: %s", newref);
1269 error("unable to delete existing %s", newref);
1274 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1275 error("unable to create directory for %s", newref);
1280 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1281 if (errno==EISDIR || errno==ENOTDIR) {
1283 * rename(a, b) when b is an existing
1284 * directory ought to result in ISDIR, but
1285 * Solaris 5.8 gives ENOTDIR. Sheesh.
1287 if (remove_empty_directories(git_path("logs/%s", newref))) {
1288 error("Directory not empty: logs/%s", newref);
1293 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1294 newref, strerror(errno));
1300 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1302 error("unable to lock %s for update", newref);
1305 lock->force_write = 1;
1306 hashcpy(lock->old_sha1, orig_sha1);
1307 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1308 error("unable to write current sha1 into %s", newref);
1315 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1317 error("unable to lock %s for rollback", oldref);
1321 lock->force_write = 1;
1322 flag = log_all_ref_updates;
1323 log_all_ref_updates = 0;
1324 if (write_ref_sha1(lock, orig_sha1, NULL))
1325 error("unable to write current sha1 into %s", oldref);
1326 log_all_ref_updates = flag;
1329 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1330 error("unable to restore logfile %s from %s: %s",
1331 oldref, newref, strerror(errno));
1332 if (!logmoved && log &&
1333 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1334 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1335 oldref, strerror(errno));
1340 int close_ref(struct ref_lock *lock)
1342 if (close_lock_file(lock->lk))
1348 int commit_ref(struct ref_lock *lock)
1350 if (commit_lock_file(lock->lk))
1356 void unlock_ref(struct ref_lock *lock)
1358 /* Do not free lock->lk -- atexit() still looks at them */
1360 rollback_lock_file(lock->lk);
1361 free(lock->ref_name);
1362 free(lock->orig_ref_name);
1367 * copy the reflog message msg to buf, which has been allocated sufficiently
1368 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1369 * because reflog file is one line per entry.
1371 static int copy_msg(char *buf, const char *msg)
1378 while ((c = *msg++)) {
1379 if (wasspace && isspace(c))
1381 wasspace = isspace(c);
1386 while (buf < cp && isspace(cp[-1]))
1392 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1394 int logfd, oflags = O_APPEND | O_WRONLY;
1396 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1397 if (log_all_ref_updates &&
1398 (!prefixcmp(ref_name, "refs/heads/") ||
1399 !prefixcmp(ref_name, "refs/remotes/") ||
1400 !prefixcmp(ref_name, "refs/notes/") ||
1401 !strcmp(ref_name, "HEAD"))) {
1402 if (safe_create_leading_directories(logfile) < 0)
1403 return error("unable to create directory for %s",
1408 logfd = open(logfile, oflags, 0666);
1410 if (!(oflags & O_CREAT) && errno == ENOENT)
1413 if ((oflags & O_CREAT) && errno == EISDIR) {
1414 if (remove_empty_directories(logfile)) {
1415 return error("There are still logs under '%s'",
1418 logfd = open(logfile, oflags, 0666);
1422 return error("Unable to append to %s: %s",
1423 logfile, strerror(errno));
1426 adjust_shared_perm(logfile);
1431 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1432 const unsigned char *new_sha1, const char *msg)
1434 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1435 unsigned maxlen, len;
1437 char log_file[PATH_MAX];
1439 const char *committer;
1441 if (log_all_ref_updates < 0)
1442 log_all_ref_updates = !is_bare_repository();
1444 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1448 logfd = open(log_file, oflags);
1451 msglen = msg ? strlen(msg) : 0;
1452 committer = git_committer_info(0);
1453 maxlen = strlen(committer) + msglen + 100;
1454 logrec = xmalloc(maxlen);
1455 len = sprintf(logrec, "%s %s %s\n",
1456 sha1_to_hex(old_sha1),
1457 sha1_to_hex(new_sha1),
1460 len += copy_msg(logrec + len - 1, msg) - 1;
1461 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1463 if (close(logfd) != 0 || written != len)
1464 return error("Unable to append to %s", log_file);
1468 static int is_branch(const char *refname)
1470 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1473 int write_ref_sha1(struct ref_lock *lock,
1474 const unsigned char *sha1, const char *logmsg)
1476 static char term = '\n';
1481 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1485 o = parse_object(sha1);
1487 error("Trying to write ref %s with nonexistent object %s",
1488 lock->ref_name, sha1_to_hex(sha1));
1492 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1493 error("Trying to write non-commit object %s to branch %s",
1494 sha1_to_hex(sha1), lock->ref_name);
1498 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1499 write_in_full(lock->lock_fd, &term, 1) != 1
1500 || close_ref(lock) < 0) {
1501 error("Couldn't write %s", lock->lk->filename);
1505 invalidate_cached_refs();
1506 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1507 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1508 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1512 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1514 * Special hack: If a branch is updated directly and HEAD
1515 * points to it (may happen on the remote side of a push
1516 * for example) then logically the HEAD reflog should be
1518 * A generic solution implies reverse symref information,
1519 * but finding all symrefs pointing to the given branch
1520 * would be rather costly for this rare event (the direct
1521 * update of a branch) to be worth it. So let's cheat and
1522 * check with HEAD only which should cover 99% of all usage
1523 * scenarios (even 100% of the default ones).
1525 unsigned char head_sha1[20];
1527 const char *head_ref;
1528 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1529 if (head_ref && (head_flag & REF_ISSYMREF) &&
1530 !strcmp(head_ref, lock->ref_name))
1531 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1533 if (commit_ref(lock)) {
1534 error("Couldn't set %s", lock->ref_name);
1542 int create_symref(const char *ref_target, const char *refs_heads_master,
1545 const char *lockpath;
1547 int fd, len, written;
1548 char *git_HEAD = git_pathdup("%s", ref_target);
1549 unsigned char old_sha1[20], new_sha1[20];
1551 if (logmsg && read_ref(ref_target, old_sha1))
1554 if (safe_create_leading_directories(git_HEAD) < 0)
1555 return error("unable to create directory for %s", git_HEAD);
1557 #ifndef NO_SYMLINK_HEAD
1558 if (prefer_symlink_refs) {
1560 if (!symlink(refs_heads_master, git_HEAD))
1562 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1566 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1567 if (sizeof(ref) <= len) {
1568 error("refname too long: %s", refs_heads_master);
1569 goto error_free_return;
1571 lockpath = mkpath("%s.lock", git_HEAD);
1572 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1574 error("Unable to open %s for writing", lockpath);
1575 goto error_free_return;
1577 written = write_in_full(fd, ref, len);
1578 if (close(fd) != 0 || written != len) {
1579 error("Unable to write to %s", lockpath);
1580 goto error_unlink_return;
1582 if (rename(lockpath, git_HEAD) < 0) {
1583 error("Unable to create %s", git_HEAD);
1584 goto error_unlink_return;
1586 if (adjust_shared_perm(git_HEAD)) {
1587 error("Unable to fix permissions on %s", lockpath);
1588 error_unlink_return:
1589 unlink_or_warn(lockpath);
1595 #ifndef NO_SYMLINK_HEAD
1598 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1599 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1605 static char *ref_msg(const char *line, const char *endp)
1609 ep = memchr(line, '\n', endp - line);
1612 return xmemdupz(line, ep - line);
1615 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)
1617 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1619 int logfd, tz, reccnt = 0;
1622 unsigned char logged_sha1[20];
1626 logfile = git_path("logs/%s", ref);
1627 logfd = open(logfile, O_RDONLY, 0);
1629 die_errno("Unable to read log '%s'", logfile);
1632 die("Log %s is empty.", logfile);
1633 mapsz = xsize_t(st.st_size);
1634 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1635 logdata = log_mapped;
1639 rec = logend = logdata + st.st_size;
1640 while (logdata < rec) {
1642 if (logdata < rec && *(rec-1) == '\n')
1645 while (logdata < rec && *(rec-1) != '\n') {
1651 die("Log %s is corrupt.", logfile);
1652 date = strtoul(lastgt + 1, &tz_c, 10);
1653 if (date <= at_time || cnt == 0) {
1654 tz = strtoul(tz_c, NULL, 10);
1656 *msg = ref_msg(rec, logend);
1658 *cutoff_time = date;
1662 *cutoff_cnt = reccnt - 1;
1664 if (get_sha1_hex(lastrec, logged_sha1))
1665 die("Log %s is corrupt.", logfile);
1666 if (get_sha1_hex(rec + 41, sha1))
1667 die("Log %s is corrupt.", logfile);
1668 if (hashcmp(logged_sha1, sha1)) {
1669 warning("Log %s has gap after %s.",
1670 logfile, show_date(date, tz, DATE_RFC2822));
1673 else if (date == at_time) {
1674 if (get_sha1_hex(rec + 41, sha1))
1675 die("Log %s is corrupt.", logfile);
1678 if (get_sha1_hex(rec + 41, logged_sha1))
1679 die("Log %s is corrupt.", logfile);
1680 if (hashcmp(logged_sha1, sha1)) {
1681 warning("Log %s unexpectedly ended on %s.",
1682 logfile, show_date(date, tz, DATE_RFC2822));
1685 munmap(log_mapped, mapsz);
1694 while (rec < logend && *rec != '>' && *rec != '\n')
1696 if (rec == logend || *rec == '\n')
1697 die("Log %s is corrupt.", logfile);
1698 date = strtoul(rec + 1, &tz_c, 10);
1699 tz = strtoul(tz_c, NULL, 10);
1700 if (get_sha1_hex(logdata, sha1))
1701 die("Log %s is corrupt.", logfile);
1702 if (is_null_sha1(sha1)) {
1703 if (get_sha1_hex(logdata + 41, sha1))
1704 die("Log %s is corrupt.", logfile);
1707 *msg = ref_msg(logdata, logend);
1708 munmap(log_mapped, mapsz);
1711 *cutoff_time = date;
1715 *cutoff_cnt = reccnt;
1719 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1721 const char *logfile;
1723 struct strbuf sb = STRBUF_INIT;
1726 logfile = git_path("logs/%s", ref);
1727 logfp = fopen(logfile, "r");
1732 struct stat statbuf;
1733 if (fstat(fileno(logfp), &statbuf) ||
1734 statbuf.st_size < ofs ||
1735 fseek(logfp, -ofs, SEEK_END) ||
1736 strbuf_getwholeline(&sb, logfp, '\n')) {
1738 strbuf_release(&sb);
1743 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1744 unsigned char osha1[20], nsha1[20];
1745 char *email_end, *message;
1746 unsigned long timestamp;
1749 /* old SP new SP name <email> SP time TAB msg LF */
1750 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1751 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1752 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1753 !(email_end = strchr(sb.buf + 82, '>')) ||
1754 email_end[1] != ' ' ||
1755 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1756 !message || message[0] != ' ' ||
1757 (message[1] != '+' && message[1] != '-') ||
1758 !isdigit(message[2]) || !isdigit(message[3]) ||
1759 !isdigit(message[4]) || !isdigit(message[5]))
1760 continue; /* corrupt? */
1761 email_end[1] = '\0';
1762 tz = strtol(message + 1, NULL, 10);
1763 if (message[6] != '\t')
1767 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1773 strbuf_release(&sb);
1777 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1779 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1782 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1784 DIR *dir = opendir(git_path("logs/%s", base));
1789 int baselen = strlen(base);
1790 char *log = xmalloc(baselen + 257);
1792 memcpy(log, base, baselen);
1793 if (baselen && base[baselen-1] != '/')
1794 log[baselen++] = '/';
1796 while ((de = readdir(dir)) != NULL) {
1800 if (de->d_name[0] == '.')
1802 namelen = strlen(de->d_name);
1805 if (has_extension(de->d_name, ".lock"))
1807 memcpy(log + baselen, de->d_name, namelen+1);
1808 if (stat(git_path("logs/%s", log), &st) < 0)
1810 if (S_ISDIR(st.st_mode)) {
1811 retval = do_for_each_reflog(log, fn, cb_data);
1813 unsigned char sha1[20];
1814 if (!resolve_ref(log, sha1, 0, NULL))
1815 retval = error("bad ref for %s", log);
1817 retval = fn(log, sha1, 0, cb_data);
1830 int for_each_reflog(each_ref_fn fn, void *cb_data)
1832 return do_for_each_reflog("", fn, cb_data);
1835 int update_ref(const char *action, const char *refname,
1836 const unsigned char *sha1, const unsigned char *oldval,
1837 int flags, enum action_on_err onerr)
1839 static struct ref_lock *lock;
1840 lock = lock_any_ref_for_update(refname, oldval, flags);
1842 const char *str = "Cannot lock the ref '%s'.";
1844 case MSG_ON_ERR: error(str, refname); break;
1845 case DIE_ON_ERR: die(str, refname); break;
1846 case QUIET_ON_ERR: break;
1850 if (write_ref_sha1(lock, sha1, action) < 0) {
1851 const char *str = "Cannot update the ref '%s'.";
1853 case MSG_ON_ERR: error(str, refname); break;
1854 case DIE_ON_ERR: die(str, refname); break;
1855 case QUIET_ON_ERR: break;
1862 int ref_exists(char *refname)
1864 unsigned char sha1[20];
1865 return !!resolve_ref(refname, sha1, 1, NULL);
1868 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1870 for ( ; list; list = list->next)
1871 if (!strcmp(list->name, name))
1872 return (struct ref *)list;
1877 * generate a format suitable for scanf from a ref_rev_parse_rules
1878 * rule, that is replace the "%.*s" spec with a "%s" spec
1880 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1884 spec = strstr(rule, "%.*s");
1885 if (!spec || strstr(spec + 4, "%.*s"))
1886 die("invalid rule in ref_rev_parse_rules: %s", rule);
1888 /* copy all until spec */
1889 strncpy(scanf_fmt, rule, spec - rule);
1890 scanf_fmt[spec - rule] = '\0';
1892 strcat(scanf_fmt, "%s");
1893 /* copy remaining rule */
1894 strcat(scanf_fmt, spec + 4);
1899 char *shorten_unambiguous_ref(const char *ref, int strict)
1902 static char **scanf_fmts;
1903 static int nr_rules;
1906 /* pre generate scanf formats from ref_rev_parse_rules[] */
1908 size_t total_len = 0;
1910 /* the rule list is NULL terminated, count them first */
1911 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1912 /* no +1 because strlen("%s") < strlen("%.*s") */
1913 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1915 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1918 for (i = 0; i < nr_rules; i++) {
1919 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1921 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1922 total_len += strlen(ref_rev_parse_rules[i]);
1926 /* bail out if there are no rules */
1928 return xstrdup(ref);
1930 /* buffer for scanf result, at most ref must fit */
1931 short_name = xstrdup(ref);
1933 /* skip first rule, it will always match */
1934 for (i = nr_rules - 1; i > 0 ; --i) {
1936 int rules_to_fail = i;
1939 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1942 short_name_len = strlen(short_name);
1945 * in strict mode, all (except the matched one) rules
1946 * must fail to resolve to a valid non-ambiguous ref
1949 rules_to_fail = nr_rules;
1952 * check if the short name resolves to a valid ref,
1953 * but use only rules prior to the matched one
1955 for (j = 0; j < rules_to_fail; j++) {
1956 const char *rule = ref_rev_parse_rules[j];
1957 unsigned char short_objectname[20];
1958 char refname[PATH_MAX];
1960 /* skip matched rule */
1965 * the short name is ambiguous, if it resolves
1966 * (with this previous rule) to a valid ref
1967 * read_ref() returns 0 on success
1969 mksnpath(refname, sizeof(refname),
1970 rule, short_name_len, short_name);
1971 if (!read_ref(refname, short_objectname))
1976 * short name is non-ambiguous if all previous rules
1977 * haven't resolved to a valid ref
1979 if (j == rules_to_fail)
1984 return xstrdup(ref);