grep: do not unnecessarily query repo for "--"
[git/debian.git] / refs.c
blobcd36b64ed93f821936fd7ffb68e60ce384119898
1 /*
2 * The backend-independent part of the reference module.
3 */
5 #include "cache.h"
6 #include "lockfile.h"
7 #include "refs.h"
8 #include "refs/refs-internal.h"
9 #include "object.h"
10 #include "tag.h"
13 * List of all available backends
15 static struct ref_storage_be *refs_backends = &refs_be_files;
17 static struct ref_storage_be *find_ref_storage_backend(const char *name)
19 struct ref_storage_be *be;
20 for (be = refs_backends; be; be = be->next)
21 if (!strcmp(be->name, name))
22 return be;
23 return NULL;
26 int ref_storage_backend_exists(const char *name)
28 return find_ref_storage_backend(name) != NULL;
32 * How to handle various characters in refnames:
33 * 0: An acceptable character for refs
34 * 1: End-of-component
35 * 2: ., look for a preceding . to reject .. in refs
36 * 3: {, look for a preceding @ to reject @{ in refs
37 * 4: A bad character: ASCII control characters, and
38 * ":", "?", "[", "\", "^", "~", SP, or TAB
39 * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
41 static unsigned char refname_disposition[256] = {
42 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
43 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
44 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
45 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
46 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
47 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
48 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
49 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
53 * Try to read one refname component from the front of refname.
54 * Return the length of the component found, or -1 if the component is
55 * not legal. It is legal if it is something reasonable to have under
56 * ".git/refs/"; We do not like it if:
58 * - any path component of it begins with ".", or
59 * - it has double dots "..", or
60 * - it has ASCII control characters, or
61 * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
62 * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
63 * - it ends with a "/", or
64 * - it ends with ".lock", or
65 * - it contains a "@{" portion
67 static int check_refname_component(const char *refname, int *flags)
69 const char *cp;
70 char last = '\0';
72 for (cp = refname; ; cp++) {
73 int ch = *cp & 255;
74 unsigned char disp = refname_disposition[ch];
75 switch (disp) {
76 case 1:
77 goto out;
78 case 2:
79 if (last == '.')
80 return -1; /* Refname contains "..". */
81 break;
82 case 3:
83 if (last == '@')
84 return -1; /* Refname contains "@{". */
85 break;
86 case 4:
87 return -1;
88 case 5:
89 if (!(*flags & REFNAME_REFSPEC_PATTERN))
90 return -1; /* refspec can't be a pattern */
93 * Unset the pattern flag so that we only accept
94 * a single asterisk for one side of refspec.
96 *flags &= ~ REFNAME_REFSPEC_PATTERN;
97 break;
99 last = ch;
101 out:
102 if (cp == refname)
103 return 0; /* Component has zero length. */
104 if (refname[0] == '.')
105 return -1; /* Component starts with '.'. */
106 if (cp - refname >= LOCK_SUFFIX_LEN &&
107 !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
108 return -1; /* Refname ends with ".lock". */
109 return cp - refname;
112 int check_refname_format(const char *refname, int flags)
114 int component_len, component_count = 0;
116 if (!strcmp(refname, "@"))
117 /* Refname is a single character '@'. */
118 return -1;
120 while (1) {
121 /* We are at the start of a path component. */
122 component_len = check_refname_component(refname, &flags);
123 if (component_len <= 0)
124 return -1;
126 component_count++;
127 if (refname[component_len] == '\0')
128 break;
129 /* Skip to next component. */
130 refname += component_len + 1;
133 if (refname[component_len - 1] == '.')
134 return -1; /* Refname ends with '.'. */
135 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
136 return -1; /* Refname has only one component. */
137 return 0;
140 int refname_is_safe(const char *refname)
142 const char *rest;
144 if (skip_prefix(refname, "refs/", &rest)) {
145 char *buf;
146 int result;
147 size_t restlen = strlen(rest);
149 /* rest must not be empty, or start or end with "/" */
150 if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
151 return 0;
154 * Does the refname try to escape refs/?
155 * For example: refs/foo/../bar is safe but refs/foo/../../bar
156 * is not.
158 buf = xmallocz(restlen);
159 result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
160 free(buf);
161 return result;
164 do {
165 if (!isupper(*refname) && *refname != '_')
166 return 0;
167 refname++;
168 } while (*refname);
169 return 1;
172 char *resolve_refdup(const char *refname, int resolve_flags,
173 unsigned char *sha1, int *flags)
175 return xstrdup_or_null(resolve_ref_unsafe(refname, resolve_flags,
176 sha1, flags));
179 /* The argument to filter_refs */
180 struct ref_filter {
181 const char *pattern;
182 each_ref_fn *fn;
183 void *cb_data;
186 int read_ref_full(const char *refname, int resolve_flags, unsigned char *sha1, int *flags)
188 if (resolve_ref_unsafe(refname, resolve_flags, sha1, flags))
189 return 0;
190 return -1;
193 int read_ref(const char *refname, unsigned char *sha1)
195 return read_ref_full(refname, RESOLVE_REF_READING, sha1, NULL);
198 int ref_exists(const char *refname)
200 unsigned char sha1[20];
201 return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, sha1, NULL);
204 static int filter_refs(const char *refname, const struct object_id *oid,
205 int flags, void *data)
207 struct ref_filter *filter = (struct ref_filter *)data;
209 if (wildmatch(filter->pattern, refname, 0, NULL))
210 return 0;
211 return filter->fn(refname, oid, flags, filter->cb_data);
214 enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
216 struct object *o = lookup_unknown_object(name);
218 if (o->type == OBJ_NONE) {
219 int type = sha1_object_info(name, NULL);
220 if (type < 0 || !object_as_type(o, type, 0))
221 return PEEL_INVALID;
224 if (o->type != OBJ_TAG)
225 return PEEL_NON_TAG;
227 o = deref_tag_noverify(o);
228 if (!o)
229 return PEEL_INVALID;
231 hashcpy(sha1, o->oid.hash);
232 return PEEL_PEELED;
235 struct warn_if_dangling_data {
236 FILE *fp;
237 const char *refname;
238 const struct string_list *refnames;
239 const char *msg_fmt;
242 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
243 int flags, void *cb_data)
245 struct warn_if_dangling_data *d = cb_data;
246 const char *resolves_to;
247 struct object_id junk;
249 if (!(flags & REF_ISSYMREF))
250 return 0;
252 resolves_to = resolve_ref_unsafe(refname, 0, junk.hash, NULL);
253 if (!resolves_to
254 || (d->refname
255 ? strcmp(resolves_to, d->refname)
256 : !string_list_has_string(d->refnames, resolves_to))) {
257 return 0;
260 fprintf(d->fp, d->msg_fmt, refname);
261 fputc('\n', d->fp);
262 return 0;
265 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
267 struct warn_if_dangling_data data;
269 data.fp = fp;
270 data.refname = refname;
271 data.refnames = NULL;
272 data.msg_fmt = msg_fmt;
273 for_each_rawref(warn_if_dangling_symref, &data);
276 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
278 struct warn_if_dangling_data data;
280 data.fp = fp;
281 data.refname = NULL;
282 data.refnames = refnames;
283 data.msg_fmt = msg_fmt;
284 for_each_rawref(warn_if_dangling_symref, &data);
287 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
289 return for_each_ref_in("refs/tags/", fn, cb_data);
292 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
294 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
297 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
299 return for_each_ref_in("refs/heads/", fn, cb_data);
302 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
304 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
307 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
309 return for_each_ref_in("refs/remotes/", fn, cb_data);
312 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
314 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
317 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
319 struct strbuf buf = STRBUF_INIT;
320 int ret = 0;
321 struct object_id oid;
322 int flag;
324 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
325 if (!read_ref_full(buf.buf, RESOLVE_REF_READING, oid.hash, &flag))
326 ret = fn(buf.buf, &oid, flag, cb_data);
327 strbuf_release(&buf);
329 return ret;
332 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
333 const char *prefix, void *cb_data)
335 struct strbuf real_pattern = STRBUF_INIT;
336 struct ref_filter filter;
337 int ret;
339 if (!prefix && !starts_with(pattern, "refs/"))
340 strbuf_addstr(&real_pattern, "refs/");
341 else if (prefix)
342 strbuf_addstr(&real_pattern, prefix);
343 strbuf_addstr(&real_pattern, pattern);
345 if (!has_glob_specials(pattern)) {
346 /* Append implied '/' '*' if not present. */
347 strbuf_complete(&real_pattern, '/');
348 /* No need to check for '*', there is none. */
349 strbuf_addch(&real_pattern, '*');
352 filter.pattern = real_pattern.buf;
353 filter.fn = fn;
354 filter.cb_data = cb_data;
355 ret = for_each_ref(filter_refs, &filter);
357 strbuf_release(&real_pattern);
358 return ret;
361 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
363 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
366 const char *prettify_refname(const char *name)
368 return name + (
369 starts_with(name, "refs/heads/") ? 11 :
370 starts_with(name, "refs/tags/") ? 10 :
371 starts_with(name, "refs/remotes/") ? 13 :
375 static const char *ref_rev_parse_rules[] = {
376 "%.*s",
377 "refs/%.*s",
378 "refs/tags/%.*s",
379 "refs/heads/%.*s",
380 "refs/remotes/%.*s",
381 "refs/remotes/%.*s/HEAD",
382 NULL
385 int refname_match(const char *abbrev_name, const char *full_name)
387 const char **p;
388 const int abbrev_name_len = strlen(abbrev_name);
390 for (p = ref_rev_parse_rules; *p; p++) {
391 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
392 return 1;
396 return 0;
400 * *string and *len will only be substituted, and *string returned (for
401 * later free()ing) if the string passed in is a magic short-hand form
402 * to name a branch.
404 static char *substitute_branch_name(const char **string, int *len)
406 struct strbuf buf = STRBUF_INIT;
407 int ret = interpret_branch_name(*string, *len, &buf);
409 if (ret == *len) {
410 size_t size;
411 *string = strbuf_detach(&buf, &size);
412 *len = size;
413 return (char *)*string;
416 return NULL;
419 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
421 char *last_branch = substitute_branch_name(&str, &len);
422 int refs_found = expand_ref(str, len, sha1, ref);
423 free(last_branch);
424 return refs_found;
427 int expand_ref(const char *str, int len, unsigned char *sha1, char **ref)
429 const char **p, *r;
430 int refs_found = 0;
432 *ref = NULL;
433 for (p = ref_rev_parse_rules; *p; p++) {
434 char fullref[PATH_MAX];
435 unsigned char sha1_from_ref[20];
436 unsigned char *this_result;
437 int flag;
439 this_result = refs_found ? sha1_from_ref : sha1;
440 mksnpath(fullref, sizeof(fullref), *p, len, str);
441 r = resolve_ref_unsafe(fullref, RESOLVE_REF_READING,
442 this_result, &flag);
443 if (r) {
444 if (!refs_found++)
445 *ref = xstrdup(r);
446 if (!warn_ambiguous_refs)
447 break;
448 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
449 warning("ignoring dangling symref %s.", fullref);
450 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
451 warning("ignoring broken ref %s.", fullref);
454 return refs_found;
457 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
459 char *last_branch = substitute_branch_name(&str, &len);
460 const char **p;
461 int logs_found = 0;
463 *log = NULL;
464 for (p = ref_rev_parse_rules; *p; p++) {
465 unsigned char hash[20];
466 char path[PATH_MAX];
467 const char *ref, *it;
469 mksnpath(path, sizeof(path), *p, len, str);
470 ref = resolve_ref_unsafe(path, RESOLVE_REF_READING,
471 hash, NULL);
472 if (!ref)
473 continue;
474 if (reflog_exists(path))
475 it = path;
476 else if (strcmp(ref, path) && reflog_exists(ref))
477 it = ref;
478 else
479 continue;
480 if (!logs_found++) {
481 *log = xstrdup(it);
482 hashcpy(sha1, hash);
484 if (!warn_ambiguous_refs)
485 break;
487 free(last_branch);
488 return logs_found;
491 static int is_per_worktree_ref(const char *refname)
493 return !strcmp(refname, "HEAD") ||
494 starts_with(refname, "refs/bisect/");
497 static int is_pseudoref_syntax(const char *refname)
499 const char *c;
501 for (c = refname; *c; c++) {
502 if (!isupper(*c) && *c != '-' && *c != '_')
503 return 0;
506 return 1;
509 enum ref_type ref_type(const char *refname)
511 if (is_per_worktree_ref(refname))
512 return REF_TYPE_PER_WORKTREE;
513 if (is_pseudoref_syntax(refname))
514 return REF_TYPE_PSEUDOREF;
515 return REF_TYPE_NORMAL;
518 static int write_pseudoref(const char *pseudoref, const unsigned char *sha1,
519 const unsigned char *old_sha1, struct strbuf *err)
521 const char *filename;
522 int fd;
523 static struct lock_file lock;
524 struct strbuf buf = STRBUF_INIT;
525 int ret = -1;
527 strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
529 filename = git_path("%s", pseudoref);
530 fd = hold_lock_file_for_update(&lock, filename, LOCK_DIE_ON_ERROR);
531 if (fd < 0) {
532 strbuf_addf(err, "could not open '%s' for writing: %s",
533 filename, strerror(errno));
534 return -1;
537 if (old_sha1) {
538 unsigned char actual_old_sha1[20];
540 if (read_ref(pseudoref, actual_old_sha1))
541 die("could not read ref '%s'", pseudoref);
542 if (hashcmp(actual_old_sha1, old_sha1)) {
543 strbuf_addf(err, "unexpected sha1 when writing '%s'", pseudoref);
544 rollback_lock_file(&lock);
545 goto done;
549 if (write_in_full(fd, buf.buf, buf.len) != buf.len) {
550 strbuf_addf(err, "could not write to '%s'", filename);
551 rollback_lock_file(&lock);
552 goto done;
555 commit_lock_file(&lock);
556 ret = 0;
557 done:
558 strbuf_release(&buf);
559 return ret;
562 static int delete_pseudoref(const char *pseudoref, const unsigned char *old_sha1)
564 static struct lock_file lock;
565 const char *filename;
567 filename = git_path("%s", pseudoref);
569 if (old_sha1 && !is_null_sha1(old_sha1)) {
570 int fd;
571 unsigned char actual_old_sha1[20];
573 fd = hold_lock_file_for_update(&lock, filename,
574 LOCK_DIE_ON_ERROR);
575 if (fd < 0)
576 die_errno(_("Could not open '%s' for writing"), filename);
577 if (read_ref(pseudoref, actual_old_sha1))
578 die("could not read ref '%s'", pseudoref);
579 if (hashcmp(actual_old_sha1, old_sha1)) {
580 warning("Unexpected sha1 when deleting %s", pseudoref);
581 rollback_lock_file(&lock);
582 return -1;
585 unlink(filename);
586 rollback_lock_file(&lock);
587 } else {
588 unlink(filename);
591 return 0;
594 int delete_ref(const char *refname, const unsigned char *old_sha1,
595 unsigned int flags)
597 struct ref_transaction *transaction;
598 struct strbuf err = STRBUF_INIT;
600 if (ref_type(refname) == REF_TYPE_PSEUDOREF)
601 return delete_pseudoref(refname, old_sha1);
603 transaction = ref_transaction_begin(&err);
604 if (!transaction ||
605 ref_transaction_delete(transaction, refname, old_sha1,
606 flags, NULL, &err) ||
607 ref_transaction_commit(transaction, &err)) {
608 error("%s", err.buf);
609 ref_transaction_free(transaction);
610 strbuf_release(&err);
611 return 1;
613 ref_transaction_free(transaction);
614 strbuf_release(&err);
615 return 0;
618 int copy_reflog_msg(char *buf, const char *msg)
620 char *cp = buf;
621 char c;
622 int wasspace = 1;
624 *cp++ = '\t';
625 while ((c = *msg++)) {
626 if (wasspace && isspace(c))
627 continue;
628 wasspace = isspace(c);
629 if (wasspace)
630 c = ' ';
631 *cp++ = c;
633 while (buf < cp && isspace(cp[-1]))
634 cp--;
635 *cp++ = '\n';
636 return cp - buf;
639 int should_autocreate_reflog(const char *refname)
641 switch (log_all_ref_updates) {
642 case LOG_REFS_ALWAYS:
643 return 1;
644 case LOG_REFS_NORMAL:
645 return starts_with(refname, "refs/heads/") ||
646 starts_with(refname, "refs/remotes/") ||
647 starts_with(refname, "refs/notes/") ||
648 !strcmp(refname, "HEAD");
649 default:
650 return 0;
654 int is_branch(const char *refname)
656 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
659 struct read_ref_at_cb {
660 const char *refname;
661 unsigned long at_time;
662 int cnt;
663 int reccnt;
664 unsigned char *sha1;
665 int found_it;
667 unsigned char osha1[20];
668 unsigned char nsha1[20];
669 int tz;
670 unsigned long date;
671 char **msg;
672 unsigned long *cutoff_time;
673 int *cutoff_tz;
674 int *cutoff_cnt;
677 static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1,
678 const char *email, unsigned long timestamp, int tz,
679 const char *message, void *cb_data)
681 struct read_ref_at_cb *cb = cb_data;
683 cb->reccnt++;
684 cb->tz = tz;
685 cb->date = timestamp;
687 if (timestamp <= cb->at_time || cb->cnt == 0) {
688 if (cb->msg)
689 *cb->msg = xstrdup(message);
690 if (cb->cutoff_time)
691 *cb->cutoff_time = timestamp;
692 if (cb->cutoff_tz)
693 *cb->cutoff_tz = tz;
694 if (cb->cutoff_cnt)
695 *cb->cutoff_cnt = cb->reccnt - 1;
697 * we have not yet updated cb->[n|o]sha1 so they still
698 * hold the values for the previous record.
700 if (!is_null_sha1(cb->osha1)) {
701 hashcpy(cb->sha1, nsha1);
702 if (hashcmp(cb->osha1, nsha1))
703 warning("Log for ref %s has gap after %s.",
704 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
706 else if (cb->date == cb->at_time)
707 hashcpy(cb->sha1, nsha1);
708 else if (hashcmp(nsha1, cb->sha1))
709 warning("Log for ref %s unexpectedly ended on %s.",
710 cb->refname, show_date(cb->date, cb->tz,
711 DATE_MODE(RFC2822)));
712 hashcpy(cb->osha1, osha1);
713 hashcpy(cb->nsha1, nsha1);
714 cb->found_it = 1;
715 return 1;
717 hashcpy(cb->osha1, osha1);
718 hashcpy(cb->nsha1, nsha1);
719 if (cb->cnt > 0)
720 cb->cnt--;
721 return 0;
724 static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1,
725 const char *email, unsigned long timestamp,
726 int tz, const char *message, void *cb_data)
728 struct read_ref_at_cb *cb = cb_data;
730 if (cb->msg)
731 *cb->msg = xstrdup(message);
732 if (cb->cutoff_time)
733 *cb->cutoff_time = timestamp;
734 if (cb->cutoff_tz)
735 *cb->cutoff_tz = tz;
736 if (cb->cutoff_cnt)
737 *cb->cutoff_cnt = cb->reccnt;
738 hashcpy(cb->sha1, osha1);
739 if (is_null_sha1(cb->sha1))
740 hashcpy(cb->sha1, nsha1);
741 /* We just want the first entry */
742 return 1;
745 int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, int cnt,
746 unsigned char *sha1, char **msg,
747 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
749 struct read_ref_at_cb cb;
751 memset(&cb, 0, sizeof(cb));
752 cb.refname = refname;
753 cb.at_time = at_time;
754 cb.cnt = cnt;
755 cb.msg = msg;
756 cb.cutoff_time = cutoff_time;
757 cb.cutoff_tz = cutoff_tz;
758 cb.cutoff_cnt = cutoff_cnt;
759 cb.sha1 = sha1;
761 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
763 if (!cb.reccnt) {
764 if (flags & GET_SHA1_QUIETLY)
765 exit(128);
766 else
767 die("Log for %s is empty.", refname);
769 if (cb.found_it)
770 return 0;
772 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
774 return 1;
777 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
779 assert(err);
781 return xcalloc(1, sizeof(struct ref_transaction));
784 void ref_transaction_free(struct ref_transaction *transaction)
786 int i;
788 if (!transaction)
789 return;
791 for (i = 0; i < transaction->nr; i++) {
792 free(transaction->updates[i]->msg);
793 free(transaction->updates[i]);
795 free(transaction->updates);
796 free(transaction);
799 struct ref_update *ref_transaction_add_update(
800 struct ref_transaction *transaction,
801 const char *refname, unsigned int flags,
802 const unsigned char *new_sha1,
803 const unsigned char *old_sha1,
804 const char *msg)
806 struct ref_update *update;
808 if (transaction->state != REF_TRANSACTION_OPEN)
809 die("BUG: update called for transaction that is not open");
811 if ((flags & REF_ISPRUNING) && !(flags & REF_NODEREF))
812 die("BUG: REF_ISPRUNING set without REF_NODEREF");
814 FLEX_ALLOC_STR(update, refname, refname);
815 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
816 transaction->updates[transaction->nr++] = update;
818 update->flags = flags;
820 if (flags & REF_HAVE_NEW)
821 hashcpy(update->new_sha1, new_sha1);
822 if (flags & REF_HAVE_OLD)
823 hashcpy(update->old_sha1, old_sha1);
824 update->msg = xstrdup_or_null(msg);
825 return update;
828 int ref_transaction_update(struct ref_transaction *transaction,
829 const char *refname,
830 const unsigned char *new_sha1,
831 const unsigned char *old_sha1,
832 unsigned int flags, const char *msg,
833 struct strbuf *err)
835 assert(err);
837 if ((new_sha1 && !is_null_sha1(new_sha1)) ?
838 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
839 !refname_is_safe(refname)) {
840 strbuf_addf(err, "refusing to update ref with bad name '%s'",
841 refname);
842 return -1;
845 flags |= (new_sha1 ? REF_HAVE_NEW : 0) | (old_sha1 ? REF_HAVE_OLD : 0);
847 ref_transaction_add_update(transaction, refname, flags,
848 new_sha1, old_sha1, msg);
849 return 0;
852 int ref_transaction_create(struct ref_transaction *transaction,
853 const char *refname,
854 const unsigned char *new_sha1,
855 unsigned int flags, const char *msg,
856 struct strbuf *err)
858 if (!new_sha1 || is_null_sha1(new_sha1))
859 die("BUG: create called without valid new_sha1");
860 return ref_transaction_update(transaction, refname, new_sha1,
861 null_sha1, flags, msg, err);
864 int ref_transaction_delete(struct ref_transaction *transaction,
865 const char *refname,
866 const unsigned char *old_sha1,
867 unsigned int flags, const char *msg,
868 struct strbuf *err)
870 if (old_sha1 && is_null_sha1(old_sha1))
871 die("BUG: delete called with old_sha1 set to zeros");
872 return ref_transaction_update(transaction, refname,
873 null_sha1, old_sha1,
874 flags, msg, err);
877 int ref_transaction_verify(struct ref_transaction *transaction,
878 const char *refname,
879 const unsigned char *old_sha1,
880 unsigned int flags,
881 struct strbuf *err)
883 if (!old_sha1)
884 die("BUG: verify called with old_sha1 set to NULL");
885 return ref_transaction_update(transaction, refname,
886 NULL, old_sha1,
887 flags, NULL, err);
890 int update_ref_oid(const char *msg, const char *refname,
891 const struct object_id *new_oid, const struct object_id *old_oid,
892 unsigned int flags, enum action_on_err onerr)
894 return update_ref(msg, refname, new_oid ? new_oid->hash : NULL,
895 old_oid ? old_oid->hash : NULL, flags, onerr);
898 int update_ref(const char *msg, const char *refname,
899 const unsigned char *new_sha1, const unsigned char *old_sha1,
900 unsigned int flags, enum action_on_err onerr)
902 struct ref_transaction *t = NULL;
903 struct strbuf err = STRBUF_INIT;
904 int ret = 0;
906 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
907 ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
908 } else {
909 t = ref_transaction_begin(&err);
910 if (!t ||
911 ref_transaction_update(t, refname, new_sha1, old_sha1,
912 flags, msg, &err) ||
913 ref_transaction_commit(t, &err)) {
914 ret = 1;
915 ref_transaction_free(t);
918 if (ret) {
919 const char *str = "update_ref failed for ref '%s': %s";
921 switch (onerr) {
922 case UPDATE_REFS_MSG_ON_ERR:
923 error(str, refname, err.buf);
924 break;
925 case UPDATE_REFS_DIE_ON_ERR:
926 die(str, refname, err.buf);
927 break;
928 case UPDATE_REFS_QUIET_ON_ERR:
929 break;
931 strbuf_release(&err);
932 return 1;
934 strbuf_release(&err);
935 if (t)
936 ref_transaction_free(t);
937 return 0;
940 char *shorten_unambiguous_ref(const char *refname, int strict)
942 int i;
943 static char **scanf_fmts;
944 static int nr_rules;
945 char *short_name;
947 if (!nr_rules) {
949 * Pre-generate scanf formats from ref_rev_parse_rules[].
950 * Generate a format suitable for scanf from a
951 * ref_rev_parse_rules rule by interpolating "%s" at the
952 * location of the "%.*s".
954 size_t total_len = 0;
955 size_t offset = 0;
957 /* the rule list is NULL terminated, count them first */
958 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
959 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
960 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
962 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
964 offset = 0;
965 for (i = 0; i < nr_rules; i++) {
966 assert(offset < total_len);
967 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
968 offset += snprintf(scanf_fmts[i], total_len - offset,
969 ref_rev_parse_rules[i], 2, "%s") + 1;
973 /* bail out if there are no rules */
974 if (!nr_rules)
975 return xstrdup(refname);
977 /* buffer for scanf result, at most refname must fit */
978 short_name = xstrdup(refname);
980 /* skip first rule, it will always match */
981 for (i = nr_rules - 1; i > 0 ; --i) {
982 int j;
983 int rules_to_fail = i;
984 int short_name_len;
986 if (1 != sscanf(refname, scanf_fmts[i], short_name))
987 continue;
989 short_name_len = strlen(short_name);
992 * in strict mode, all (except the matched one) rules
993 * must fail to resolve to a valid non-ambiguous ref
995 if (strict)
996 rules_to_fail = nr_rules;
999 * check if the short name resolves to a valid ref,
1000 * but use only rules prior to the matched one
1002 for (j = 0; j < rules_to_fail; j++) {
1003 const char *rule = ref_rev_parse_rules[j];
1004 char refname[PATH_MAX];
1006 /* skip matched rule */
1007 if (i == j)
1008 continue;
1011 * the short name is ambiguous, if it resolves
1012 * (with this previous rule) to a valid ref
1013 * read_ref() returns 0 on success
1015 mksnpath(refname, sizeof(refname),
1016 rule, short_name_len, short_name);
1017 if (ref_exists(refname))
1018 break;
1022 * short name is non-ambiguous if all previous rules
1023 * haven't resolved to a valid ref
1025 if (j == rules_to_fail)
1026 return short_name;
1029 free(short_name);
1030 return xstrdup(refname);
1033 static struct string_list *hide_refs;
1035 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1037 if (!strcmp("transfer.hiderefs", var) ||
1038 /* NEEDSWORK: use parse_config_key() once both are merged */
1039 (starts_with(var, section) && var[strlen(section)] == '.' &&
1040 !strcmp(var + strlen(section), ".hiderefs"))) {
1041 char *ref;
1042 int len;
1044 if (!value)
1045 return config_error_nonbool(var);
1046 ref = xstrdup(value);
1047 len = strlen(ref);
1048 while (len && ref[len - 1] == '/')
1049 ref[--len] = '\0';
1050 if (!hide_refs) {
1051 hide_refs = xcalloc(1, sizeof(*hide_refs));
1052 hide_refs->strdup_strings = 1;
1054 string_list_append(hide_refs, ref);
1056 return 0;
1059 int ref_is_hidden(const char *refname, const char *refname_full)
1061 int i;
1063 if (!hide_refs)
1064 return 0;
1065 for (i = hide_refs->nr - 1; i >= 0; i--) {
1066 const char *match = hide_refs->items[i].string;
1067 const char *subject;
1068 int neg = 0;
1069 int len;
1071 if (*match == '!') {
1072 neg = 1;
1073 match++;
1076 if (*match == '^') {
1077 subject = refname_full;
1078 match++;
1079 } else {
1080 subject = refname;
1083 /* refname can be NULL when namespaces are used. */
1084 if (!subject || !starts_with(subject, match))
1085 continue;
1086 len = strlen(match);
1087 if (!subject[len] || subject[len] == '/')
1088 return !neg;
1090 return 0;
1093 const char *find_descendant_ref(const char *dirname,
1094 const struct string_list *extras,
1095 const struct string_list *skip)
1097 int pos;
1099 if (!extras)
1100 return NULL;
1103 * Look at the place where dirname would be inserted into
1104 * extras. If there is an entry at that position that starts
1105 * with dirname (remember, dirname includes the trailing
1106 * slash) and is not in skip, then we have a conflict.
1108 for (pos = string_list_find_insert_index(extras, dirname, 0);
1109 pos < extras->nr; pos++) {
1110 const char *extra_refname = extras->items[pos].string;
1112 if (!starts_with(extra_refname, dirname))
1113 break;
1115 if (!skip || !string_list_has_string(skip, extra_refname))
1116 return extra_refname;
1118 return NULL;
1121 int rename_ref_available(const char *old_refname, const char *new_refname)
1123 struct string_list skip = STRING_LIST_INIT_NODUP;
1124 struct strbuf err = STRBUF_INIT;
1125 int ok;
1127 string_list_insert(&skip, old_refname);
1128 ok = !verify_refname_available(new_refname, NULL, &skip, &err);
1129 if (!ok)
1130 error("%s", err.buf);
1132 string_list_clear(&skip, 0);
1133 strbuf_release(&err);
1134 return ok;
1137 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1139 struct object_id oid;
1140 int flag;
1142 if (submodule) {
1143 if (resolve_gitlink_ref(submodule, "HEAD", oid.hash) == 0)
1144 return fn("HEAD", &oid, 0, cb_data);
1146 return 0;
1149 if (!read_ref_full("HEAD", RESOLVE_REF_READING, oid.hash, &flag))
1150 return fn("HEAD", &oid, flag, cb_data);
1152 return 0;
1155 int head_ref(each_ref_fn fn, void *cb_data)
1157 return head_ref_submodule(NULL, fn, cb_data);
1161 * Call fn for each reference in the specified submodule for which the
1162 * refname begins with prefix. If trim is non-zero, then trim that
1163 * many characters off the beginning of each refname before passing
1164 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1165 * include broken references in the iteration. If fn ever returns a
1166 * non-zero value, stop the iteration and return that value;
1167 * otherwise, return 0.
1169 static int do_for_each_ref(const char *submodule, const char *prefix,
1170 each_ref_fn fn, int trim, int flags, void *cb_data)
1172 struct ref_store *refs = get_ref_store(submodule);
1173 struct ref_iterator *iter;
1175 if (!refs)
1176 return 0;
1178 iter = refs->be->iterator_begin(refs, prefix, flags);
1179 iter = prefix_ref_iterator_begin(iter, prefix, trim);
1181 return do_for_each_ref_iterator(iter, fn, cb_data);
1184 int for_each_ref(each_ref_fn fn, void *cb_data)
1186 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
1189 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1191 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
1194 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1196 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
1199 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1201 unsigned int flag = 0;
1203 if (broken)
1204 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1205 return do_for_each_ref(NULL, prefix, fn, 0, flag, cb_data);
1208 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1209 each_ref_fn fn, void *cb_data)
1211 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
1214 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1216 return do_for_each_ref(NULL, git_replace_ref_base, fn,
1217 strlen(git_replace_ref_base), 0, cb_data);
1220 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1222 struct strbuf buf = STRBUF_INIT;
1223 int ret;
1224 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1225 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1226 strbuf_release(&buf);
1227 return ret;
1230 int for_each_rawref(each_ref_fn fn, void *cb_data)
1232 return do_for_each_ref(NULL, "", fn, 0,
1233 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1236 /* This function needs to return a meaningful errno on failure */
1237 static const char *resolve_ref_recursively(struct ref_store *refs,
1238 const char *refname,
1239 int resolve_flags,
1240 unsigned char *sha1, int *flags)
1242 static struct strbuf sb_refname = STRBUF_INIT;
1243 int unused_flags;
1244 int symref_count;
1246 if (!flags)
1247 flags = &unused_flags;
1249 *flags = 0;
1251 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1252 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1253 !refname_is_safe(refname)) {
1254 errno = EINVAL;
1255 return NULL;
1259 * dwim_ref() uses REF_ISBROKEN to distinguish between
1260 * missing refs and refs that were present but invalid,
1261 * to complain about the latter to stderr.
1263 * We don't know whether the ref exists, so don't set
1264 * REF_ISBROKEN yet.
1266 *flags |= REF_BAD_NAME;
1269 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1270 unsigned int read_flags = 0;
1272 if (refs->be->read_raw_ref(refs, refname,
1273 sha1, &sb_refname, &read_flags)) {
1274 *flags |= read_flags;
1275 if (errno != ENOENT || (resolve_flags & RESOLVE_REF_READING))
1276 return NULL;
1277 hashclr(sha1);
1278 if (*flags & REF_BAD_NAME)
1279 *flags |= REF_ISBROKEN;
1280 return refname;
1283 *flags |= read_flags;
1285 if (!(read_flags & REF_ISSYMREF)) {
1286 if (*flags & REF_BAD_NAME) {
1287 hashclr(sha1);
1288 *flags |= REF_ISBROKEN;
1290 return refname;
1293 refname = sb_refname.buf;
1294 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1295 hashclr(sha1);
1296 return refname;
1298 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1299 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1300 !refname_is_safe(refname)) {
1301 errno = EINVAL;
1302 return NULL;
1305 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1309 errno = ELOOP;
1310 return NULL;
1313 /* backend functions */
1314 int refs_init_db(struct strbuf *err)
1316 struct ref_store *refs = get_ref_store(NULL);
1318 return refs->be->init_db(refs, err);
1321 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1322 unsigned char *sha1, int *flags)
1324 return resolve_ref_recursively(get_ref_store(NULL), refname,
1325 resolve_flags, sha1, flags);
1328 int resolve_gitlink_ref(const char *submodule, const char *refname,
1329 unsigned char *sha1)
1331 size_t len = strlen(submodule);
1332 struct ref_store *refs;
1333 int flags;
1335 while (len && submodule[len - 1] == '/')
1336 len--;
1338 if (!len)
1339 return -1;
1341 if (submodule[len]) {
1342 /* We need to strip off one or more trailing slashes */
1343 char *stripped = xmemdupz(submodule, len);
1345 refs = get_ref_store(stripped);
1346 free(stripped);
1347 } else {
1348 refs = get_ref_store(submodule);
1351 if (!refs)
1352 return -1;
1354 if (!resolve_ref_recursively(refs, refname, 0, sha1, &flags) ||
1355 is_null_sha1(sha1))
1356 return -1;
1357 return 0;
1360 /* A pointer to the ref_store for the main repository: */
1361 static struct ref_store *main_ref_store;
1363 /* A linked list of ref_stores for submodules: */
1364 static struct ref_store *submodule_ref_stores;
1366 void base_ref_store_init(struct ref_store *refs,
1367 const struct ref_storage_be *be,
1368 const char *submodule)
1370 refs->be = be;
1371 if (!submodule) {
1372 if (main_ref_store)
1373 die("BUG: main_ref_store initialized twice");
1375 refs->submodule = "";
1376 refs->next = NULL;
1377 main_ref_store = refs;
1378 } else {
1379 if (lookup_ref_store(submodule))
1380 die("BUG: ref_store for submodule '%s' initialized twice",
1381 submodule);
1383 refs->submodule = xstrdup(submodule);
1384 refs->next = submodule_ref_stores;
1385 submodule_ref_stores = refs;
1389 struct ref_store *ref_store_init(const char *submodule)
1391 const char *be_name = "files";
1392 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1394 if (!be)
1395 die("BUG: reference backend %s is unknown", be_name);
1397 if (!submodule || !*submodule)
1398 return be->init(NULL);
1399 else
1400 return be->init(submodule);
1403 struct ref_store *lookup_ref_store(const char *submodule)
1405 struct ref_store *refs;
1407 if (!submodule || !*submodule)
1408 return main_ref_store;
1410 for (refs = submodule_ref_stores; refs; refs = refs->next) {
1411 if (!strcmp(submodule, refs->submodule))
1412 return refs;
1415 return NULL;
1418 struct ref_store *get_ref_store(const char *submodule)
1420 struct ref_store *refs;
1422 if (!submodule || !*submodule) {
1423 refs = lookup_ref_store(NULL);
1425 if (!refs)
1426 refs = ref_store_init(NULL);
1427 } else {
1428 refs = lookup_ref_store(submodule);
1430 if (!refs) {
1431 struct strbuf submodule_sb = STRBUF_INIT;
1433 strbuf_addstr(&submodule_sb, submodule);
1434 if (is_nonbare_repository_dir(&submodule_sb))
1435 refs = ref_store_init(submodule);
1436 strbuf_release(&submodule_sb);
1440 return refs;
1443 void assert_main_repository(struct ref_store *refs, const char *caller)
1445 if (*refs->submodule)
1446 die("BUG: %s called for a submodule", caller);
1449 /* backend functions */
1450 int pack_refs(unsigned int flags)
1452 struct ref_store *refs = get_ref_store(NULL);
1454 return refs->be->pack_refs(refs, flags);
1457 int peel_ref(const char *refname, unsigned char *sha1)
1459 struct ref_store *refs = get_ref_store(NULL);
1461 return refs->be->peel_ref(refs, refname, sha1);
1464 int create_symref(const char *ref_target, const char *refs_heads_master,
1465 const char *logmsg)
1467 struct ref_store *refs = get_ref_store(NULL);
1469 return refs->be->create_symref(refs, ref_target, refs_heads_master,
1470 logmsg);
1473 int ref_transaction_commit(struct ref_transaction *transaction,
1474 struct strbuf *err)
1476 struct ref_store *refs = get_ref_store(NULL);
1478 return refs->be->transaction_commit(refs, transaction, err);
1481 int verify_refname_available(const char *refname,
1482 const struct string_list *extra,
1483 const struct string_list *skip,
1484 struct strbuf *err)
1486 struct ref_store *refs = get_ref_store(NULL);
1488 return refs->be->verify_refname_available(refs, refname, extra, skip, err);
1491 int for_each_reflog(each_ref_fn fn, void *cb_data)
1493 struct ref_store *refs = get_ref_store(NULL);
1494 struct ref_iterator *iter;
1496 iter = refs->be->reflog_iterator_begin(refs);
1498 return do_for_each_ref_iterator(iter, fn, cb_data);
1501 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
1502 void *cb_data)
1504 struct ref_store *refs = get_ref_store(NULL);
1506 return refs->be->for_each_reflog_ent_reverse(refs, refname,
1507 fn, cb_data);
1510 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
1511 void *cb_data)
1513 struct ref_store *refs = get_ref_store(NULL);
1515 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
1518 int reflog_exists(const char *refname)
1520 struct ref_store *refs = get_ref_store(NULL);
1522 return refs->be->reflog_exists(refs, refname);
1525 int safe_create_reflog(const char *refname, int force_create,
1526 struct strbuf *err)
1528 struct ref_store *refs = get_ref_store(NULL);
1530 return refs->be->create_reflog(refs, refname, force_create, err);
1533 int delete_reflog(const char *refname)
1535 struct ref_store *refs = get_ref_store(NULL);
1537 return refs->be->delete_reflog(refs, refname);
1540 int reflog_expire(const char *refname, const unsigned char *sha1,
1541 unsigned int flags,
1542 reflog_expiry_prepare_fn prepare_fn,
1543 reflog_expiry_should_prune_fn should_prune_fn,
1544 reflog_expiry_cleanup_fn cleanup_fn,
1545 void *policy_cb_data)
1547 struct ref_store *refs = get_ref_store(NULL);
1549 return refs->be->reflog_expire(refs, refname, sha1, flags,
1550 prepare_fn, should_prune_fn,
1551 cleanup_fn, policy_cb_data);
1554 int initial_ref_transaction_commit(struct ref_transaction *transaction,
1555 struct strbuf *err)
1557 struct ref_store *refs = get_ref_store(NULL);
1559 return refs->be->initial_transaction_commit(refs, transaction, err);
1562 int delete_refs(struct string_list *refnames, unsigned int flags)
1564 struct ref_store *refs = get_ref_store(NULL);
1566 return refs->be->delete_refs(refs, refnames, flags);
1569 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1571 struct ref_store *refs = get_ref_store(NULL);
1573 return refs->be->rename_ref(refs, oldref, newref, logmsg);