fsck: check HAS_OBJ more consistently
[git/debian.git] / refs.c
blob9bd0bc177bb8298148577ce0c3e52134452d6e51
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 if (!log_all_ref_updates)
642 return 0;
643 return starts_with(refname, "refs/heads/") ||
644 starts_with(refname, "refs/remotes/") ||
645 starts_with(refname, "refs/notes/") ||
646 !strcmp(refname, "HEAD");
649 int is_branch(const char *refname)
651 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
654 struct read_ref_at_cb {
655 const char *refname;
656 unsigned long at_time;
657 int cnt;
658 int reccnt;
659 unsigned char *sha1;
660 int found_it;
662 unsigned char osha1[20];
663 unsigned char nsha1[20];
664 int tz;
665 unsigned long date;
666 char **msg;
667 unsigned long *cutoff_time;
668 int *cutoff_tz;
669 int *cutoff_cnt;
672 static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1,
673 const char *email, unsigned long timestamp, int tz,
674 const char *message, void *cb_data)
676 struct read_ref_at_cb *cb = cb_data;
678 cb->reccnt++;
679 cb->tz = tz;
680 cb->date = timestamp;
682 if (timestamp <= cb->at_time || cb->cnt == 0) {
683 if (cb->msg)
684 *cb->msg = xstrdup(message);
685 if (cb->cutoff_time)
686 *cb->cutoff_time = timestamp;
687 if (cb->cutoff_tz)
688 *cb->cutoff_tz = tz;
689 if (cb->cutoff_cnt)
690 *cb->cutoff_cnt = cb->reccnt - 1;
692 * we have not yet updated cb->[n|o]sha1 so they still
693 * hold the values for the previous record.
695 if (!is_null_sha1(cb->osha1)) {
696 hashcpy(cb->sha1, nsha1);
697 if (hashcmp(cb->osha1, nsha1))
698 warning("Log for ref %s has gap after %s.",
699 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
701 else if (cb->date == cb->at_time)
702 hashcpy(cb->sha1, nsha1);
703 else if (hashcmp(nsha1, cb->sha1))
704 warning("Log for ref %s unexpectedly ended on %s.",
705 cb->refname, show_date(cb->date, cb->tz,
706 DATE_MODE(RFC2822)));
707 hashcpy(cb->osha1, osha1);
708 hashcpy(cb->nsha1, nsha1);
709 cb->found_it = 1;
710 return 1;
712 hashcpy(cb->osha1, osha1);
713 hashcpy(cb->nsha1, nsha1);
714 if (cb->cnt > 0)
715 cb->cnt--;
716 return 0;
719 static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1,
720 const char *email, unsigned long timestamp,
721 int tz, const char *message, void *cb_data)
723 struct read_ref_at_cb *cb = cb_data;
725 if (cb->msg)
726 *cb->msg = xstrdup(message);
727 if (cb->cutoff_time)
728 *cb->cutoff_time = timestamp;
729 if (cb->cutoff_tz)
730 *cb->cutoff_tz = tz;
731 if (cb->cutoff_cnt)
732 *cb->cutoff_cnt = cb->reccnt;
733 hashcpy(cb->sha1, osha1);
734 if (is_null_sha1(cb->sha1))
735 hashcpy(cb->sha1, nsha1);
736 /* We just want the first entry */
737 return 1;
740 int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, int cnt,
741 unsigned char *sha1, char **msg,
742 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
744 struct read_ref_at_cb cb;
746 memset(&cb, 0, sizeof(cb));
747 cb.refname = refname;
748 cb.at_time = at_time;
749 cb.cnt = cnt;
750 cb.msg = msg;
751 cb.cutoff_time = cutoff_time;
752 cb.cutoff_tz = cutoff_tz;
753 cb.cutoff_cnt = cutoff_cnt;
754 cb.sha1 = sha1;
756 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
758 if (!cb.reccnt) {
759 if (flags & GET_SHA1_QUIETLY)
760 exit(128);
761 else
762 die("Log for %s is empty.", refname);
764 if (cb.found_it)
765 return 0;
767 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
769 return 1;
772 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
774 assert(err);
776 return xcalloc(1, sizeof(struct ref_transaction));
779 void ref_transaction_free(struct ref_transaction *transaction)
781 int i;
783 if (!transaction)
784 return;
786 for (i = 0; i < transaction->nr; i++) {
787 free(transaction->updates[i]->msg);
788 free(transaction->updates[i]);
790 free(transaction->updates);
791 free(transaction);
794 struct ref_update *ref_transaction_add_update(
795 struct ref_transaction *transaction,
796 const char *refname, unsigned int flags,
797 const unsigned char *new_sha1,
798 const unsigned char *old_sha1,
799 const char *msg)
801 struct ref_update *update;
803 if (transaction->state != REF_TRANSACTION_OPEN)
804 die("BUG: update called for transaction that is not open");
806 if ((flags & REF_ISPRUNING) && !(flags & REF_NODEREF))
807 die("BUG: REF_ISPRUNING set without REF_NODEREF");
809 FLEX_ALLOC_STR(update, refname, refname);
810 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
811 transaction->updates[transaction->nr++] = update;
813 update->flags = flags;
815 if (flags & REF_HAVE_NEW)
816 hashcpy(update->new_sha1, new_sha1);
817 if (flags & REF_HAVE_OLD)
818 hashcpy(update->old_sha1, old_sha1);
819 update->msg = xstrdup_or_null(msg);
820 return update;
823 int ref_transaction_update(struct ref_transaction *transaction,
824 const char *refname,
825 const unsigned char *new_sha1,
826 const unsigned char *old_sha1,
827 unsigned int flags, const char *msg,
828 struct strbuf *err)
830 assert(err);
832 if ((new_sha1 && !is_null_sha1(new_sha1)) ?
833 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
834 !refname_is_safe(refname)) {
835 strbuf_addf(err, "refusing to update ref with bad name '%s'",
836 refname);
837 return -1;
840 flags |= (new_sha1 ? REF_HAVE_NEW : 0) | (old_sha1 ? REF_HAVE_OLD : 0);
842 ref_transaction_add_update(transaction, refname, flags,
843 new_sha1, old_sha1, msg);
844 return 0;
847 int ref_transaction_create(struct ref_transaction *transaction,
848 const char *refname,
849 const unsigned char *new_sha1,
850 unsigned int flags, const char *msg,
851 struct strbuf *err)
853 if (!new_sha1 || is_null_sha1(new_sha1))
854 die("BUG: create called without valid new_sha1");
855 return ref_transaction_update(transaction, refname, new_sha1,
856 null_sha1, flags, msg, err);
859 int ref_transaction_delete(struct ref_transaction *transaction,
860 const char *refname,
861 const unsigned char *old_sha1,
862 unsigned int flags, const char *msg,
863 struct strbuf *err)
865 if (old_sha1 && is_null_sha1(old_sha1))
866 die("BUG: delete called with old_sha1 set to zeros");
867 return ref_transaction_update(transaction, refname,
868 null_sha1, old_sha1,
869 flags, msg, err);
872 int ref_transaction_verify(struct ref_transaction *transaction,
873 const char *refname,
874 const unsigned char *old_sha1,
875 unsigned int flags,
876 struct strbuf *err)
878 if (!old_sha1)
879 die("BUG: verify called with old_sha1 set to NULL");
880 return ref_transaction_update(transaction, refname,
881 NULL, old_sha1,
882 flags, NULL, err);
885 int update_ref_oid(const char *msg, const char *refname,
886 const struct object_id *new_oid, const struct object_id *old_oid,
887 unsigned int flags, enum action_on_err onerr)
889 return update_ref(msg, refname, new_oid ? new_oid->hash : NULL,
890 old_oid ? old_oid->hash : NULL, flags, onerr);
893 int update_ref(const char *msg, const char *refname,
894 const unsigned char *new_sha1, const unsigned char *old_sha1,
895 unsigned int flags, enum action_on_err onerr)
897 struct ref_transaction *t = NULL;
898 struct strbuf err = STRBUF_INIT;
899 int ret = 0;
901 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
902 ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
903 } else {
904 t = ref_transaction_begin(&err);
905 if (!t ||
906 ref_transaction_update(t, refname, new_sha1, old_sha1,
907 flags, msg, &err) ||
908 ref_transaction_commit(t, &err)) {
909 ret = 1;
910 ref_transaction_free(t);
913 if (ret) {
914 const char *str = "update_ref failed for ref '%s': %s";
916 switch (onerr) {
917 case UPDATE_REFS_MSG_ON_ERR:
918 error(str, refname, err.buf);
919 break;
920 case UPDATE_REFS_DIE_ON_ERR:
921 die(str, refname, err.buf);
922 break;
923 case UPDATE_REFS_QUIET_ON_ERR:
924 break;
926 strbuf_release(&err);
927 return 1;
929 strbuf_release(&err);
930 if (t)
931 ref_transaction_free(t);
932 return 0;
935 char *shorten_unambiguous_ref(const char *refname, int strict)
937 int i;
938 static char **scanf_fmts;
939 static int nr_rules;
940 char *short_name;
942 if (!nr_rules) {
944 * Pre-generate scanf formats from ref_rev_parse_rules[].
945 * Generate a format suitable for scanf from a
946 * ref_rev_parse_rules rule by interpolating "%s" at the
947 * location of the "%.*s".
949 size_t total_len = 0;
950 size_t offset = 0;
952 /* the rule list is NULL terminated, count them first */
953 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
954 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
955 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
957 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
959 offset = 0;
960 for (i = 0; i < nr_rules; i++) {
961 assert(offset < total_len);
962 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
963 offset += snprintf(scanf_fmts[i], total_len - offset,
964 ref_rev_parse_rules[i], 2, "%s") + 1;
968 /* bail out if there are no rules */
969 if (!nr_rules)
970 return xstrdup(refname);
972 /* buffer for scanf result, at most refname must fit */
973 short_name = xstrdup(refname);
975 /* skip first rule, it will always match */
976 for (i = nr_rules - 1; i > 0 ; --i) {
977 int j;
978 int rules_to_fail = i;
979 int short_name_len;
981 if (1 != sscanf(refname, scanf_fmts[i], short_name))
982 continue;
984 short_name_len = strlen(short_name);
987 * in strict mode, all (except the matched one) rules
988 * must fail to resolve to a valid non-ambiguous ref
990 if (strict)
991 rules_to_fail = nr_rules;
994 * check if the short name resolves to a valid ref,
995 * but use only rules prior to the matched one
997 for (j = 0; j < rules_to_fail; j++) {
998 const char *rule = ref_rev_parse_rules[j];
999 char refname[PATH_MAX];
1001 /* skip matched rule */
1002 if (i == j)
1003 continue;
1006 * the short name is ambiguous, if it resolves
1007 * (with this previous rule) to a valid ref
1008 * read_ref() returns 0 on success
1010 mksnpath(refname, sizeof(refname),
1011 rule, short_name_len, short_name);
1012 if (ref_exists(refname))
1013 break;
1017 * short name is non-ambiguous if all previous rules
1018 * haven't resolved to a valid ref
1020 if (j == rules_to_fail)
1021 return short_name;
1024 free(short_name);
1025 return xstrdup(refname);
1028 static struct string_list *hide_refs;
1030 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1032 if (!strcmp("transfer.hiderefs", var) ||
1033 /* NEEDSWORK: use parse_config_key() once both are merged */
1034 (starts_with(var, section) && var[strlen(section)] == '.' &&
1035 !strcmp(var + strlen(section), ".hiderefs"))) {
1036 char *ref;
1037 int len;
1039 if (!value)
1040 return config_error_nonbool(var);
1041 ref = xstrdup(value);
1042 len = strlen(ref);
1043 while (len && ref[len - 1] == '/')
1044 ref[--len] = '\0';
1045 if (!hide_refs) {
1046 hide_refs = xcalloc(1, sizeof(*hide_refs));
1047 hide_refs->strdup_strings = 1;
1049 string_list_append(hide_refs, ref);
1051 return 0;
1054 int ref_is_hidden(const char *refname, const char *refname_full)
1056 int i;
1058 if (!hide_refs)
1059 return 0;
1060 for (i = hide_refs->nr - 1; i >= 0; i--) {
1061 const char *match = hide_refs->items[i].string;
1062 const char *subject;
1063 int neg = 0;
1064 int len;
1066 if (*match == '!') {
1067 neg = 1;
1068 match++;
1071 if (*match == '^') {
1072 subject = refname_full;
1073 match++;
1074 } else {
1075 subject = refname;
1078 /* refname can be NULL when namespaces are used. */
1079 if (!subject || !starts_with(subject, match))
1080 continue;
1081 len = strlen(match);
1082 if (!subject[len] || subject[len] == '/')
1083 return !neg;
1085 return 0;
1088 const char *find_descendant_ref(const char *dirname,
1089 const struct string_list *extras,
1090 const struct string_list *skip)
1092 int pos;
1094 if (!extras)
1095 return NULL;
1098 * Look at the place where dirname would be inserted into
1099 * extras. If there is an entry at that position that starts
1100 * with dirname (remember, dirname includes the trailing
1101 * slash) and is not in skip, then we have a conflict.
1103 for (pos = string_list_find_insert_index(extras, dirname, 0);
1104 pos < extras->nr; pos++) {
1105 const char *extra_refname = extras->items[pos].string;
1107 if (!starts_with(extra_refname, dirname))
1108 break;
1110 if (!skip || !string_list_has_string(skip, extra_refname))
1111 return extra_refname;
1113 return NULL;
1116 int rename_ref_available(const char *old_refname, const char *new_refname)
1118 struct string_list skip = STRING_LIST_INIT_NODUP;
1119 struct strbuf err = STRBUF_INIT;
1120 int ok;
1122 string_list_insert(&skip, old_refname);
1123 ok = !verify_refname_available(new_refname, NULL, &skip, &err);
1124 if (!ok)
1125 error("%s", err.buf);
1127 string_list_clear(&skip, 0);
1128 strbuf_release(&err);
1129 return ok;
1132 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1134 struct object_id oid;
1135 int flag;
1137 if (submodule) {
1138 if (resolve_gitlink_ref(submodule, "HEAD", oid.hash) == 0)
1139 return fn("HEAD", &oid, 0, cb_data);
1141 return 0;
1144 if (!read_ref_full("HEAD", RESOLVE_REF_READING, oid.hash, &flag))
1145 return fn("HEAD", &oid, flag, cb_data);
1147 return 0;
1150 int head_ref(each_ref_fn fn, void *cb_data)
1152 return head_ref_submodule(NULL, fn, cb_data);
1156 * Call fn for each reference in the specified submodule for which the
1157 * refname begins with prefix. If trim is non-zero, then trim that
1158 * many characters off the beginning of each refname before passing
1159 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1160 * include broken references in the iteration. If fn ever returns a
1161 * non-zero value, stop the iteration and return that value;
1162 * otherwise, return 0.
1164 static int do_for_each_ref(const char *submodule, const char *prefix,
1165 each_ref_fn fn, int trim, int flags, void *cb_data)
1167 struct ref_store *refs = get_ref_store(submodule);
1168 struct ref_iterator *iter;
1170 if (!refs)
1171 return 0;
1173 iter = refs->be->iterator_begin(refs, prefix, flags);
1174 iter = prefix_ref_iterator_begin(iter, prefix, trim);
1176 return do_for_each_ref_iterator(iter, fn, cb_data);
1179 int for_each_ref(each_ref_fn fn, void *cb_data)
1181 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
1184 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1186 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
1189 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1191 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
1194 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1196 unsigned int flag = 0;
1198 if (broken)
1199 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1200 return do_for_each_ref(NULL, prefix, fn, 0, flag, cb_data);
1203 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1204 each_ref_fn fn, void *cb_data)
1206 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
1209 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1211 return do_for_each_ref(NULL, git_replace_ref_base, fn,
1212 strlen(git_replace_ref_base), 0, cb_data);
1215 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1217 struct strbuf buf = STRBUF_INIT;
1218 int ret;
1219 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1220 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1221 strbuf_release(&buf);
1222 return ret;
1225 int for_each_rawref(each_ref_fn fn, void *cb_data)
1227 return do_for_each_ref(NULL, "", fn, 0,
1228 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1231 /* This function needs to return a meaningful errno on failure */
1232 static const char *resolve_ref_recursively(struct ref_store *refs,
1233 const char *refname,
1234 int resolve_flags,
1235 unsigned char *sha1, int *flags)
1237 static struct strbuf sb_refname = STRBUF_INIT;
1238 int unused_flags;
1239 int symref_count;
1241 if (!flags)
1242 flags = &unused_flags;
1244 *flags = 0;
1246 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1247 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1248 !refname_is_safe(refname)) {
1249 errno = EINVAL;
1250 return NULL;
1254 * dwim_ref() uses REF_ISBROKEN to distinguish between
1255 * missing refs and refs that were present but invalid,
1256 * to complain about the latter to stderr.
1258 * We don't know whether the ref exists, so don't set
1259 * REF_ISBROKEN yet.
1261 *flags |= REF_BAD_NAME;
1264 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1265 unsigned int read_flags = 0;
1267 if (refs->be->read_raw_ref(refs, refname,
1268 sha1, &sb_refname, &read_flags)) {
1269 *flags |= read_flags;
1270 if (errno != ENOENT || (resolve_flags & RESOLVE_REF_READING))
1271 return NULL;
1272 hashclr(sha1);
1273 if (*flags & REF_BAD_NAME)
1274 *flags |= REF_ISBROKEN;
1275 return refname;
1278 *flags |= read_flags;
1280 if (!(read_flags & REF_ISSYMREF)) {
1281 if (*flags & REF_BAD_NAME) {
1282 hashclr(sha1);
1283 *flags |= REF_ISBROKEN;
1285 return refname;
1288 refname = sb_refname.buf;
1289 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1290 hashclr(sha1);
1291 return refname;
1293 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1294 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1295 !refname_is_safe(refname)) {
1296 errno = EINVAL;
1297 return NULL;
1300 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1304 errno = ELOOP;
1305 return NULL;
1308 /* backend functions */
1309 int refs_init_db(struct strbuf *err)
1311 struct ref_store *refs = get_ref_store(NULL);
1313 return refs->be->init_db(refs, err);
1316 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1317 unsigned char *sha1, int *flags)
1319 return resolve_ref_recursively(get_ref_store(NULL), refname,
1320 resolve_flags, sha1, flags);
1323 int resolve_gitlink_ref(const char *submodule, const char *refname,
1324 unsigned char *sha1)
1326 size_t len = strlen(submodule);
1327 struct ref_store *refs;
1328 int flags;
1330 while (len && submodule[len - 1] == '/')
1331 len--;
1333 if (!len)
1334 return -1;
1336 if (submodule[len]) {
1337 /* We need to strip off one or more trailing slashes */
1338 char *stripped = xmemdupz(submodule, len);
1340 refs = get_ref_store(stripped);
1341 free(stripped);
1342 } else {
1343 refs = get_ref_store(submodule);
1346 if (!refs)
1347 return -1;
1349 if (!resolve_ref_recursively(refs, refname, 0, sha1, &flags) ||
1350 is_null_sha1(sha1))
1351 return -1;
1352 return 0;
1355 /* A pointer to the ref_store for the main repository: */
1356 static struct ref_store *main_ref_store;
1358 /* A linked list of ref_stores for submodules: */
1359 static struct ref_store *submodule_ref_stores;
1361 void base_ref_store_init(struct ref_store *refs,
1362 const struct ref_storage_be *be,
1363 const char *submodule)
1365 refs->be = be;
1366 if (!submodule) {
1367 if (main_ref_store)
1368 die("BUG: main_ref_store initialized twice");
1370 refs->submodule = "";
1371 refs->next = NULL;
1372 main_ref_store = refs;
1373 } else {
1374 if (lookup_ref_store(submodule))
1375 die("BUG: ref_store for submodule '%s' initialized twice",
1376 submodule);
1378 refs->submodule = xstrdup(submodule);
1379 refs->next = submodule_ref_stores;
1380 submodule_ref_stores = refs;
1384 struct ref_store *ref_store_init(const char *submodule)
1386 const char *be_name = "files";
1387 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1389 if (!be)
1390 die("BUG: reference backend %s is unknown", be_name);
1392 if (!submodule || !*submodule)
1393 return be->init(NULL);
1394 else
1395 return be->init(submodule);
1398 struct ref_store *lookup_ref_store(const char *submodule)
1400 struct ref_store *refs;
1402 if (!submodule || !*submodule)
1403 return main_ref_store;
1405 for (refs = submodule_ref_stores; refs; refs = refs->next) {
1406 if (!strcmp(submodule, refs->submodule))
1407 return refs;
1410 return NULL;
1413 struct ref_store *get_ref_store(const char *submodule)
1415 struct ref_store *refs;
1417 if (!submodule || !*submodule) {
1418 refs = lookup_ref_store(NULL);
1420 if (!refs)
1421 refs = ref_store_init(NULL);
1422 } else {
1423 refs = lookup_ref_store(submodule);
1425 if (!refs) {
1426 struct strbuf submodule_sb = STRBUF_INIT;
1428 strbuf_addstr(&submodule_sb, submodule);
1429 if (is_nonbare_repository_dir(&submodule_sb))
1430 refs = ref_store_init(submodule);
1431 strbuf_release(&submodule_sb);
1435 return refs;
1438 void assert_main_repository(struct ref_store *refs, const char *caller)
1440 if (*refs->submodule)
1441 die("BUG: %s called for a submodule", caller);
1444 /* backend functions */
1445 int pack_refs(unsigned int flags)
1447 struct ref_store *refs = get_ref_store(NULL);
1449 return refs->be->pack_refs(refs, flags);
1452 int peel_ref(const char *refname, unsigned char *sha1)
1454 struct ref_store *refs = get_ref_store(NULL);
1456 return refs->be->peel_ref(refs, refname, sha1);
1459 int create_symref(const char *ref_target, const char *refs_heads_master,
1460 const char *logmsg)
1462 struct ref_store *refs = get_ref_store(NULL);
1464 return refs->be->create_symref(refs, ref_target, refs_heads_master,
1465 logmsg);
1468 int ref_transaction_commit(struct ref_transaction *transaction,
1469 struct strbuf *err)
1471 struct ref_store *refs = get_ref_store(NULL);
1473 return refs->be->transaction_commit(refs, transaction, err);
1476 int verify_refname_available(const char *refname,
1477 const struct string_list *extra,
1478 const struct string_list *skip,
1479 struct strbuf *err)
1481 struct ref_store *refs = get_ref_store(NULL);
1483 return refs->be->verify_refname_available(refs, refname, extra, skip, err);
1486 int for_each_reflog(each_ref_fn fn, void *cb_data)
1488 struct ref_store *refs = get_ref_store(NULL);
1489 struct ref_iterator *iter;
1491 iter = refs->be->reflog_iterator_begin(refs);
1493 return do_for_each_ref_iterator(iter, fn, cb_data);
1496 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
1497 void *cb_data)
1499 struct ref_store *refs = get_ref_store(NULL);
1501 return refs->be->for_each_reflog_ent_reverse(refs, refname,
1502 fn, cb_data);
1505 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
1506 void *cb_data)
1508 struct ref_store *refs = get_ref_store(NULL);
1510 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
1513 int reflog_exists(const char *refname)
1515 struct ref_store *refs = get_ref_store(NULL);
1517 return refs->be->reflog_exists(refs, refname);
1520 int safe_create_reflog(const char *refname, int force_create,
1521 struct strbuf *err)
1523 struct ref_store *refs = get_ref_store(NULL);
1525 return refs->be->create_reflog(refs, refname, force_create, err);
1528 int delete_reflog(const char *refname)
1530 struct ref_store *refs = get_ref_store(NULL);
1532 return refs->be->delete_reflog(refs, refname);
1535 int reflog_expire(const char *refname, const unsigned char *sha1,
1536 unsigned int flags,
1537 reflog_expiry_prepare_fn prepare_fn,
1538 reflog_expiry_should_prune_fn should_prune_fn,
1539 reflog_expiry_cleanup_fn cleanup_fn,
1540 void *policy_cb_data)
1542 struct ref_store *refs = get_ref_store(NULL);
1544 return refs->be->reflog_expire(refs, refname, sha1, flags,
1545 prepare_fn, should_prune_fn,
1546 cleanup_fn, policy_cb_data);
1549 int initial_ref_transaction_commit(struct ref_transaction *transaction,
1550 struct strbuf *err)
1552 struct ref_store *refs = get_ref_store(NULL);
1554 return refs->be->initial_transaction_commit(refs, transaction, err);
1557 int delete_refs(struct string_list *refnames, unsigned int flags)
1559 struct ref_store *refs = get_ref_store(NULL);
1561 return refs->be->delete_refs(refs, refnames, flags);
1564 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1566 struct ref_store *refs = get_ref_store(NULL);
1568 return refs->be->rename_ref(refs, oldref, newref, logmsg);