1/*
2 * The backend-independent part of the reference module.
3 */
4
5#include "cache.h"
6#include "config.h"
7#include "hashmap.h"
8#include "lockfile.h"
9#include "iterator.h"
10#include "refs.h"
11#include "refs/refs-internal.h"
12#include "object.h"
13#include "tag.h"
14#include "submodule.h"
15#include "worktree.h"
16#include "argv-array.h"
17#include "repository.h"
18
19/*
20 * List of all available backends
21 */
22static struct ref_storage_be *refs_backends = &refs_be_files;
23
24static struct ref_storage_be *find_ref_storage_backend(const char *name)
25{
26 struct ref_storage_be *be;
27 for (be = refs_backends; be; be = be->next)
28 if (!strcmp(be->name, name))
29 return be;
30 return NULL;
31}
32
33int ref_storage_backend_exists(const char *name)
34{
35 return find_ref_storage_backend(name) != NULL;
36}
37
38/*
39 * How to handle various characters in refnames:
40 * 0: An acceptable character for refs
41 * 1: End-of-component
42 * 2: ., look for a preceding . to reject .. in refs
43 * 3: {, look for a preceding @ to reject @{ in refs
44 * 4: A bad character: ASCII control characters, and
45 * ":", "?", "[", "\", "^", "~", SP, or TAB
46 * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
47 */
48static unsigned char refname_disposition[256] = {
49 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
50 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
51 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
52 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
53 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
54 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
55 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
56 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
57};
58
59/*
60 * Try to read one refname component from the front of refname.
61 * Return the length of the component found, or -1 if the component is
62 * not legal. It is legal if it is something reasonable to have under
63 * ".git/refs/"; We do not like it if:
64 *
65 * - any path component of it begins with ".", or
66 * - it has double dots "..", or
67 * - it has ASCII control characters, or
68 * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
69 * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
70 * - it ends with a "/", or
71 * - it ends with ".lock", or
72 * - it contains a "@{" portion
73 */
74static int check_refname_component(const char *refname, int *flags)
75{
76 const char *cp;
77 char last = '\0';
78
79 for (cp = refname; ; cp++) {
80 int ch = *cp & 255;
81 unsigned char disp = refname_disposition[ch];
82 switch (disp) {
83 case 1:
84 goto out;
85 case 2:
86 if (last == '.')
87 return -1; /* Refname contains "..". */
88 break;
89 case 3:
90 if (last == '@')
91 return -1; /* Refname contains "@{". */
92 break;
93 case 4:
94 return -1;
95 case 5:
96 if (!(*flags & REFNAME_REFSPEC_PATTERN))
97 return -1; /* refspec can't be a pattern */
98
99 /*
100 * Unset the pattern flag so that we only accept
101 * a single asterisk for one side of refspec.
102 */
103 *flags &= ~ REFNAME_REFSPEC_PATTERN;
104 break;
105 }
106 last = ch;
107 }
108out:
109 if (cp == refname)
110 return 0; /* Component has zero length. */
111 if (refname[0] == '.')
112 return -1; /* Component starts with '.'. */
113 if (cp - refname >= LOCK_SUFFIX_LEN &&
114 !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
115 return -1; /* Refname ends with ".lock". */
116 return cp - refname;
117}
118
119int check_refname_format(const char *refname, int flags)
120{
121 int component_len, component_count = 0;
122
123 if (!strcmp(refname, "@"))
124 /* Refname is a single character '@'. */
125 return -1;
126
127 while (1) {
128 /* We are at the start of a path component. */
129 component_len = check_refname_component(refname, &flags);
130 if (component_len <= 0)
131 return -1;
132
133 component_count++;
134 if (refname[component_len] == '\0')
135 break;
136 /* Skip to next component. */
137 refname += component_len + 1;
138 }
139
140 if (refname[component_len - 1] == '.')
141 return -1; /* Refname ends with '.'. */
142 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
143 return -1; /* Refname has only one component. */
144 return 0;
145}
146
147int refname_is_safe(const char *refname)
148{
149 const char *rest;
150
151 if (skip_prefix(refname, "refs/", &rest)) {
152 char *buf;
153 int result;
154 size_t restlen = strlen(rest);
155
156 /* rest must not be empty, or start or end with "/" */
157 if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
158 return 0;
159
160 /*
161 * Does the refname try to escape refs/?
162 * For example: refs/foo/../bar is safe but refs/foo/../../bar
163 * is not.
164 */
165 buf = xmallocz(restlen);
166 result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
167 free(buf);
168 return result;
169 }
170
171 do {
172 if (!isupper(*refname) && *refname != '_')
173 return 0;
174 refname++;
175 } while (*refname);
176 return 1;
177}
178
179/*
180 * Return true if refname, which has the specified oid and flags, can
181 * be resolved to an object in the database. If the referred-to object
182 * does not exist, emit a warning and return false.
183 */
184int ref_resolves_to_object(const char *refname,
185 const struct object_id *oid,
186 unsigned int flags)
187{
188 if (flags & REF_ISBROKEN)
189 return 0;
190 if (!has_sha1_file(oid->hash)) {
191 error("%s does not point to a valid object!", refname);
192 return 0;
193 }
194 return 1;
195}
196
197char *refs_resolve_refdup(struct ref_store *refs,
198 const char *refname, int resolve_flags,
199 struct object_id *oid, int *flags)
200{
201 const char *result;
202
203 result = refs_resolve_ref_unsafe(refs, refname, resolve_flags,
204 oid, flags);
205 return xstrdup_or_null(result);
206}
207
208char *resolve_refdup(const char *refname, int resolve_flags,
209 struct object_id *oid, int *flags)
210{
211 return refs_resolve_refdup(get_main_ref_store(the_repository),
212 refname, resolve_flags,
213 oid, flags);
214}
215
216/* The argument to filter_refs */
217struct ref_filter {
218 const char *pattern;
219 each_ref_fn *fn;
220 void *cb_data;
221};
222
223int refs_read_ref_full(struct ref_store *refs, const char *refname,
224 int resolve_flags, struct object_id *oid, int *flags)
225{
226 if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, oid, flags))
227 return 0;
228 return -1;
229}
230
231int read_ref_full(const char *refname, int resolve_flags, struct object_id *oid, int *flags)
232{
233 return refs_read_ref_full(get_main_ref_store(the_repository), refname,
234 resolve_flags, oid, flags);
235}
236
237int read_ref(const char *refname, struct object_id *oid)
238{
239 return read_ref_full(refname, RESOLVE_REF_READING, oid, NULL);
240}
241
242int ref_exists(const char *refname)
243{
244 return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, NULL, NULL);
245}
246
247static int match_ref_pattern(const char *refname,
248 const struct string_list_item *item)
249{
250 int matched = 0;
251 if (item->util == NULL) {
252 if (!wildmatch(item->string, refname, 0))
253 matched = 1;
254 } else {
255 const char *rest;
256 if (skip_prefix(refname, item->string, &rest) &&
257 (!*rest || *rest == '/'))
258 matched = 1;
259 }
260 return matched;
261}
262
263int ref_filter_match(const char *refname,
264 const struct string_list *include_patterns,
265 const struct string_list *exclude_patterns)
266{
267 struct string_list_item *item;
268
269 if (exclude_patterns && exclude_patterns->nr) {
270 for_each_string_list_item(item, exclude_patterns) {
271 if (match_ref_pattern(refname, item))
272 return 0;
273 }
274 }
275
276 if (include_patterns && include_patterns->nr) {
277 int found = 0;
278 for_each_string_list_item(item, include_patterns) {
279 if (match_ref_pattern(refname, item)) {
280 found = 1;
281 break;
282 }
283 }
284
285 if (!found)
286 return 0;
287 }
288 return 1;
289}
290
291static int filter_refs(const char *refname, const struct object_id *oid,
292 int flags, void *data)
293{
294 struct ref_filter *filter = (struct ref_filter *)data;
295
296 if (wildmatch(filter->pattern, refname, 0))
297 return 0;
298 return filter->fn(refname, oid, flags, filter->cb_data);
299}
300
301enum peel_status peel_object(const struct object_id *name, struct object_id *oid)
302{
303 struct object *o = lookup_unknown_object(name->hash);
304
305 if (o->type == OBJ_NONE) {
306 int type = oid_object_info(name, NULL);
307 if (type < 0 || !object_as_type(o, type, 0))
308 return PEEL_INVALID;
309 }
310
311 if (o->type != OBJ_TAG)
312 return PEEL_NON_TAG;
313
314 o = deref_tag_noverify(o);
315 if (!o)
316 return PEEL_INVALID;
317
318 oidcpy(oid, &o->oid);
319 return PEEL_PEELED;
320}
321
322struct warn_if_dangling_data {
323 FILE *fp;
324 const char *refname;
325 const struct string_list *refnames;
326 const char *msg_fmt;
327};
328
329static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
330 int flags, void *cb_data)
331{
332 struct warn_if_dangling_data *d = cb_data;
333 const char *resolves_to;
334
335 if (!(flags & REF_ISSYMREF))
336 return 0;
337
338 resolves_to = resolve_ref_unsafe(refname, 0, NULL, NULL);
339 if (!resolves_to
340 || (d->refname
341 ? strcmp(resolves_to, d->refname)
342 : !string_list_has_string(d->refnames, resolves_to))) {
343 return 0;
344 }
345
346 fprintf(d->fp, d->msg_fmt, refname);
347 fputc('\n', d->fp);
348 return 0;
349}
350
351void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
352{
353 struct warn_if_dangling_data data;
354
355 data.fp = fp;
356 data.refname = refname;
357 data.refnames = NULL;
358 data.msg_fmt = msg_fmt;
359 for_each_rawref(warn_if_dangling_symref, &data);
360}
361
362void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
363{
364 struct warn_if_dangling_data data;
365
366 data.fp = fp;
367 data.refname = NULL;
368 data.refnames = refnames;
369 data.msg_fmt = msg_fmt;
370 for_each_rawref(warn_if_dangling_symref, &data);
371}
372
373int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
374{
375 return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
376}
377
378int for_each_tag_ref(each_ref_fn fn, void *cb_data)
379{
380 return refs_for_each_tag_ref(get_main_ref_store(the_repository), fn, cb_data);
381}
382
383int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
384{
385 return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
386}
387
388int for_each_branch_ref(each_ref_fn fn, void *cb_data)
389{
390 return refs_for_each_branch_ref(get_main_ref_store(the_repository), fn, cb_data);
391}
392
393int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
394{
395 return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
396}
397
398int for_each_remote_ref(each_ref_fn fn, void *cb_data)
399{
400 return refs_for_each_remote_ref(get_main_ref_store(the_repository), fn, cb_data);
401}
402
403int head_ref_namespaced(each_ref_fn fn, void *cb_data)
404{
405 struct strbuf buf = STRBUF_INIT;
406 int ret = 0;
407 struct object_id oid;
408 int flag;
409
410 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
411 if (!read_ref_full(buf.buf, RESOLVE_REF_READING, &oid, &flag))
412 ret = fn(buf.buf, &oid, flag, cb_data);
413 strbuf_release(&buf);
414
415 return ret;
416}
417
418void normalize_glob_ref(struct string_list_item *item, const char *prefix,
419 const char *pattern)
420{
421 struct strbuf normalized_pattern = STRBUF_INIT;
422
423 if (*pattern == '/')
424 BUG("pattern must not start with '/'");
425
426 if (prefix) {
427 strbuf_addstr(&normalized_pattern, prefix);
428 }
429 else if (!starts_with(pattern, "refs/"))
430 strbuf_addstr(&normalized_pattern, "refs/");
431 strbuf_addstr(&normalized_pattern, pattern);
432 strbuf_strip_suffix(&normalized_pattern, "/");
433
434 item->string = strbuf_detach(&normalized_pattern, NULL);
435 item->util = has_glob_specials(pattern) ? NULL : item->string;
436 strbuf_release(&normalized_pattern);
437}
438
439int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
440 const char *prefix, void *cb_data)
441{
442 struct strbuf real_pattern = STRBUF_INIT;
443 struct ref_filter filter;
444 int ret;
445
446 if (!prefix && !starts_with(pattern, "refs/"))
447 strbuf_addstr(&real_pattern, "refs/");
448 else if (prefix)
449 strbuf_addstr(&real_pattern, prefix);
450 strbuf_addstr(&real_pattern, pattern);
451
452 if (!has_glob_specials(pattern)) {
453 /* Append implied '/' '*' if not present. */
454 strbuf_complete(&real_pattern, '/');
455 /* No need to check for '*', there is none. */
456 strbuf_addch(&real_pattern, '*');
457 }
458
459 filter.pattern = real_pattern.buf;
460 filter.fn = fn;
461 filter.cb_data = cb_data;
462 ret = for_each_ref(filter_refs, &filter);
463
464 strbuf_release(&real_pattern);
465 return ret;
466}
467
468int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
469{
470 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
471}
472
473const char *prettify_refname(const char *name)
474{
475 if (skip_prefix(name, "refs/heads/", &name) ||
476 skip_prefix(name, "refs/tags/", &name) ||
477 skip_prefix(name, "refs/remotes/", &name))
478 ; /* nothing */
479 return name;
480}
481
482static const char *ref_rev_parse_rules[] = {
483 "%.*s",
484 "refs/%.*s",
485 "refs/tags/%.*s",
486 "refs/heads/%.*s",
487 "refs/remotes/%.*s",
488 "refs/remotes/%.*s/HEAD",
489 NULL
490};
491
492int refname_match(const char *abbrev_name, const char *full_name)
493{
494 const char **p;
495 const int abbrev_name_len = strlen(abbrev_name);
496
497 for (p = ref_rev_parse_rules; *p; p++) {
498 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
499 return 1;
500 }
501 }
502
503 return 0;
504}
505
506/*
507 * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add
508 * the results to 'prefixes'
509 */
510void expand_ref_prefix(struct argv_array *prefixes, const char *prefix)
511{
512 const char **p;
513 int len = strlen(prefix);
514
515 for (p = ref_rev_parse_rules; *p; p++)
516 argv_array_pushf(prefixes, *p, len, prefix);
517}
518
519/*
520 * *string and *len will only be substituted, and *string returned (for
521 * later free()ing) if the string passed in is a magic short-hand form
522 * to name a branch.
523 */
524static char *substitute_branch_name(const char **string, int *len)
525{
526 struct strbuf buf = STRBUF_INIT;
527 int ret = interpret_branch_name(*string, *len, &buf, 0);
528
529 if (ret == *len) {
530 size_t size;
531 *string = strbuf_detach(&buf, &size);
532 *len = size;
533 return (char *)*string;
534 }
535
536 return NULL;
537}
538
539int dwim_ref(const char *str, int len, struct object_id *oid, char **ref)
540{
541 char *last_branch = substitute_branch_name(&str, &len);
542 int refs_found = expand_ref(str, len, oid, ref);
543 free(last_branch);
544 return refs_found;
545}
546
547int expand_ref(const char *str, int len, struct object_id *oid, char **ref)
548{
549 const char **p, *r;
550 int refs_found = 0;
551 struct strbuf fullref = STRBUF_INIT;
552
553 *ref = NULL;
554 for (p = ref_rev_parse_rules; *p; p++) {
555 struct object_id oid_from_ref;
556 struct object_id *this_result;
557 int flag;
558
559 this_result = refs_found ? &oid_from_ref : oid;
560 strbuf_reset(&fullref);
561 strbuf_addf(&fullref, *p, len, str);
562 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
563 this_result, &flag);
564 if (r) {
565 if (!refs_found++)
566 *ref = xstrdup(r);
567 if (!warn_ambiguous_refs)
568 break;
569 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
570 warning("ignoring dangling symref %s.", fullref.buf);
571 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
572 warning("ignoring broken ref %s.", fullref.buf);
573 }
574 }
575 strbuf_release(&fullref);
576 return refs_found;
577}
578
579int dwim_log(const char *str, int len, struct object_id *oid, char **log)
580{
581 char *last_branch = substitute_branch_name(&str, &len);
582 const char **p;
583 int logs_found = 0;
584 struct strbuf path = STRBUF_INIT;
585
586 *log = NULL;
587 for (p = ref_rev_parse_rules; *p; p++) {
588 struct object_id hash;
589 const char *ref, *it;
590
591 strbuf_reset(&path);
592 strbuf_addf(&path, *p, len, str);
593 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
594 &hash, NULL);
595 if (!ref)
596 continue;
597 if (reflog_exists(path.buf))
598 it = path.buf;
599 else if (strcmp(ref, path.buf) && reflog_exists(ref))
600 it = ref;
601 else
602 continue;
603 if (!logs_found++) {
604 *log = xstrdup(it);
605 oidcpy(oid, &hash);
606 }
607 if (!warn_ambiguous_refs)
608 break;
609 }
610 strbuf_release(&path);
611 free(last_branch);
612 return logs_found;
613}
614
615static int is_per_worktree_ref(const char *refname)
616{
617 return !strcmp(refname, "HEAD") ||
618 starts_with(refname, "refs/bisect/");
619}
620
621static int is_pseudoref_syntax(const char *refname)
622{
623 const char *c;
624
625 for (c = refname; *c; c++) {
626 if (!isupper(*c) && *c != '-' && *c != '_')
627 return 0;
628 }
629
630 return 1;
631}
632
633enum ref_type ref_type(const char *refname)
634{
635 if (is_per_worktree_ref(refname))
636 return REF_TYPE_PER_WORKTREE;
637 if (is_pseudoref_syntax(refname))
638 return REF_TYPE_PSEUDOREF;
639 return REF_TYPE_NORMAL;
640}
641
642long get_files_ref_lock_timeout_ms(void)
643{
644 static int configured = 0;
645
646 /* The default timeout is 100 ms: */
647 static int timeout_ms = 100;
648
649 if (!configured) {
650 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
651 configured = 1;
652 }
653
654 return timeout_ms;
655}
656
657static int write_pseudoref(const char *pseudoref, const struct object_id *oid,
658 const struct object_id *old_oid, struct strbuf *err)
659{
660 const char *filename;
661 int fd;
662 static struct lock_file lock;
663 struct strbuf buf = STRBUF_INIT;
664 int ret = -1;
665
666 if (!oid)
667 return 0;
668
669 strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
670
671 filename = git_path("%s", pseudoref);
672 fd = hold_lock_file_for_update_timeout(&lock, filename,
673 LOCK_DIE_ON_ERROR,
674 get_files_ref_lock_timeout_ms());
675 if (fd < 0) {
676 strbuf_addf(err, "could not open '%s' for writing: %s",
677 filename, strerror(errno));
678 goto done;
679 }
680
681 if (old_oid) {
682 struct object_id actual_old_oid;
683
684 if (read_ref(pseudoref, &actual_old_oid)) {
685 if (!is_null_oid(old_oid)) {
686 strbuf_addf(err, "could not read ref '%s'",
687 pseudoref);
688 rollback_lock_file(&lock);
689 goto done;
690 }
691 } else if (is_null_oid(old_oid)) {
692 strbuf_addf(err, "ref '%s' already exists",
693 pseudoref);
694 rollback_lock_file(&lock);
695 goto done;
696 } else if (oidcmp(&actual_old_oid, old_oid)) {
697 strbuf_addf(err, "unexpected object ID when writing '%s'",
698 pseudoref);
699 rollback_lock_file(&lock);
700 goto done;
701 }
702 }
703
704 if (write_in_full(fd, buf.buf, buf.len) < 0) {
705 strbuf_addf(err, "could not write to '%s'", filename);
706 rollback_lock_file(&lock);
707 goto done;
708 }
709
710 commit_lock_file(&lock);
711 ret = 0;
712done:
713 strbuf_release(&buf);
714 return ret;
715}
716
717static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
718{
719 static struct lock_file lock;
720 const char *filename;
721
722 filename = git_path("%s", pseudoref);
723
724 if (old_oid && !is_null_oid(old_oid)) {
725 int fd;
726 struct object_id actual_old_oid;
727
728 fd = hold_lock_file_for_update_timeout(
729 &lock, filename, LOCK_DIE_ON_ERROR,
730 get_files_ref_lock_timeout_ms());
731 if (fd < 0)
732 die_errno(_("Could not open '%s' for writing"), filename);
733 if (read_ref(pseudoref, &actual_old_oid))
734 die("could not read ref '%s'", pseudoref);
735 if (oidcmp(&actual_old_oid, old_oid)) {
736 error("unexpected object ID when deleting '%s'",
737 pseudoref);
738 rollback_lock_file(&lock);
739 return -1;
740 }
741
742 unlink(filename);
743 rollback_lock_file(&lock);
744 } else {
745 unlink(filename);
746 }
747
748 return 0;
749}
750
751int refs_delete_ref(struct ref_store *refs, const char *msg,
752 const char *refname,
753 const struct object_id *old_oid,
754 unsigned int flags)
755{
756 struct ref_transaction *transaction;
757 struct strbuf err = STRBUF_INIT;
758
759 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
760 assert(refs == get_main_ref_store(the_repository));
761 return delete_pseudoref(refname, old_oid);
762 }
763
764 transaction = ref_store_transaction_begin(refs, &err);
765 if (!transaction ||
766 ref_transaction_delete(transaction, refname, old_oid,
767 flags, msg, &err) ||
768 ref_transaction_commit(transaction, &err)) {
769 error("%s", err.buf);
770 ref_transaction_free(transaction);
771 strbuf_release(&err);
772 return 1;
773 }
774 ref_transaction_free(transaction);
775 strbuf_release(&err);
776 return 0;
777}
778
779int delete_ref(const char *msg, const char *refname,
780 const struct object_id *old_oid, unsigned int flags)
781{
782 return refs_delete_ref(get_main_ref_store(the_repository), msg, refname,
783 old_oid, flags);
784}
785
786int copy_reflog_msg(char *buf, const char *msg)
787{
788 char *cp = buf;
789 char c;
790 int wasspace = 1;
791
792 *cp++ = '\t';
793 while ((c = *msg++)) {
794 if (wasspace && isspace(c))
795 continue;
796 wasspace = isspace(c);
797 if (wasspace)
798 c = ' ';
799 *cp++ = c;
800 }
801 while (buf < cp && isspace(cp[-1]))
802 cp--;
803 *cp++ = '\n';
804 return cp - buf;
805}
806
807int should_autocreate_reflog(const char *refname)
808{
809 switch (log_all_ref_updates) {
810 case LOG_REFS_ALWAYS:
811 return 1;
812 case LOG_REFS_NORMAL:
813 return starts_with(refname, "refs/heads/") ||
814 starts_with(refname, "refs/remotes/") ||
815 starts_with(refname, "refs/notes/") ||
816 !strcmp(refname, "HEAD");
817 default:
818 return 0;
819 }
820}
821
822int is_branch(const char *refname)
823{
824 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
825}
826
827struct read_ref_at_cb {
828 const char *refname;
829 timestamp_t at_time;
830 int cnt;
831 int reccnt;
832 struct object_id *oid;
833 int found_it;
834
835 struct object_id ooid;
836 struct object_id noid;
837 int tz;
838 timestamp_t date;
839 char **msg;
840 timestamp_t *cutoff_time;
841 int *cutoff_tz;
842 int *cutoff_cnt;
843};
844
845static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
846 const char *email, timestamp_t timestamp, int tz,
847 const char *message, void *cb_data)
848{
849 struct read_ref_at_cb *cb = cb_data;
850
851 cb->reccnt++;
852 cb->tz = tz;
853 cb->date = timestamp;
854
855 if (timestamp <= cb->at_time || cb->cnt == 0) {
856 if (cb->msg)
857 *cb->msg = xstrdup(message);
858 if (cb->cutoff_time)
859 *cb->cutoff_time = timestamp;
860 if (cb->cutoff_tz)
861 *cb->cutoff_tz = tz;
862 if (cb->cutoff_cnt)
863 *cb->cutoff_cnt = cb->reccnt - 1;
864 /*
865 * we have not yet updated cb->[n|o]oid so they still
866 * hold the values for the previous record.
867 */
868 if (!is_null_oid(&cb->ooid)) {
869 oidcpy(cb->oid, noid);
870 if (oidcmp(&cb->ooid, noid))
871 warning("Log for ref %s has gap after %s.",
872 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
873 }
874 else if (cb->date == cb->at_time)
875 oidcpy(cb->oid, noid);
876 else if (oidcmp(noid, cb->oid))
877 warning("Log for ref %s unexpectedly ended on %s.",
878 cb->refname, show_date(cb->date, cb->tz,
879 DATE_MODE(RFC2822)));
880 oidcpy(&cb->ooid, ooid);
881 oidcpy(&cb->noid, noid);
882 cb->found_it = 1;
883 return 1;
884 }
885 oidcpy(&cb->ooid, ooid);
886 oidcpy(&cb->noid, noid);
887 if (cb->cnt > 0)
888 cb->cnt--;
889 return 0;
890}
891
892static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
893 const char *email, timestamp_t timestamp,
894 int tz, const char *message, void *cb_data)
895{
896 struct read_ref_at_cb *cb = cb_data;
897
898 if (cb->msg)
899 *cb->msg = xstrdup(message);
900 if (cb->cutoff_time)
901 *cb->cutoff_time = timestamp;
902 if (cb->cutoff_tz)
903 *cb->cutoff_tz = tz;
904 if (cb->cutoff_cnt)
905 *cb->cutoff_cnt = cb->reccnt;
906 oidcpy(cb->oid, ooid);
907 if (is_null_oid(cb->oid))
908 oidcpy(cb->oid, noid);
909 /* We just want the first entry */
910 return 1;
911}
912
913int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
914 struct object_id *oid, char **msg,
915 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
916{
917 struct read_ref_at_cb cb;
918
919 memset(&cb, 0, sizeof(cb));
920 cb.refname = refname;
921 cb.at_time = at_time;
922 cb.cnt = cnt;
923 cb.msg = msg;
924 cb.cutoff_time = cutoff_time;
925 cb.cutoff_tz = cutoff_tz;
926 cb.cutoff_cnt = cutoff_cnt;
927 cb.oid = oid;
928
929 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
930
931 if (!cb.reccnt) {
932 if (flags & GET_OID_QUIETLY)
933 exit(128);
934 else
935 die("Log for %s is empty.", refname);
936 }
937 if (cb.found_it)
938 return 0;
939
940 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
941
942 return 1;
943}
944
945struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
946 struct strbuf *err)
947{
948 struct ref_transaction *tr;
949 assert(err);
950
951 tr = xcalloc(1, sizeof(struct ref_transaction));
952 tr->ref_store = refs;
953 return tr;
954}
955
956struct ref_transaction *ref_transaction_begin(struct strbuf *err)
957{
958 return ref_store_transaction_begin(get_main_ref_store(the_repository), err);
959}
960
961void ref_transaction_free(struct ref_transaction *transaction)
962{
963 size_t i;
964
965 if (!transaction)
966 return;
967
968 switch (transaction->state) {
969 case REF_TRANSACTION_OPEN:
970 case REF_TRANSACTION_CLOSED:
971 /* OK */
972 break;
973 case REF_TRANSACTION_PREPARED:
974 die("BUG: free called on a prepared reference transaction");
975 break;
976 default:
977 die("BUG: unexpected reference transaction state");
978 break;
979 }
980
981 for (i = 0; i < transaction->nr; i++) {
982 free(transaction->updates[i]->msg);
983 free(transaction->updates[i]);
984 }
985 free(transaction->updates);
986 free(transaction);
987}
988
989struct ref_update *ref_transaction_add_update(
990 struct ref_transaction *transaction,
991 const char *refname, unsigned int flags,
992 const struct object_id *new_oid,
993 const struct object_id *old_oid,
994 const char *msg)
995{
996 struct ref_update *update;
997
998 if (transaction->state != REF_TRANSACTION_OPEN)
999 die("BUG: update called for transaction that is not open");
1000
1001 FLEX_ALLOC_STR(update, refname, refname);
1002 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
1003 transaction->updates[transaction->nr++] = update;
1004
1005 update->flags = flags;
1006
1007 if (flags & REF_HAVE_NEW)
1008 oidcpy(&update->new_oid, new_oid);
1009 if (flags & REF_HAVE_OLD)
1010 oidcpy(&update->old_oid, old_oid);
1011 update->msg = xstrdup_or_null(msg);
1012 return update;
1013}
1014
1015int ref_transaction_update(struct ref_transaction *transaction,
1016 const char *refname,
1017 const struct object_id *new_oid,
1018 const struct object_id *old_oid,
1019 unsigned int flags, const char *msg,
1020 struct strbuf *err)
1021{
1022 assert(err);
1023
1024 if ((new_oid && !is_null_oid(new_oid)) ?
1025 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
1026 !refname_is_safe(refname)) {
1027 strbuf_addf(err, "refusing to update ref with bad name '%s'",
1028 refname);
1029 return -1;
1030 }
1031
1032 if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
1033 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
1034
1035 flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
1036
1037 ref_transaction_add_update(transaction, refname, flags,
1038 new_oid, old_oid, msg);
1039 return 0;
1040}
1041
1042int ref_transaction_create(struct ref_transaction *transaction,
1043 const char *refname,
1044 const struct object_id *new_oid,
1045 unsigned int flags, const char *msg,
1046 struct strbuf *err)
1047{
1048 if (!new_oid || is_null_oid(new_oid))
1049 die("BUG: create called without valid new_oid");
1050 return ref_transaction_update(transaction, refname, new_oid,
1051 &null_oid, flags, msg, err);
1052}
1053
1054int ref_transaction_delete(struct ref_transaction *transaction,
1055 const char *refname,
1056 const struct object_id *old_oid,
1057 unsigned int flags, const char *msg,
1058 struct strbuf *err)
1059{
1060 if (old_oid && is_null_oid(old_oid))
1061 die("BUG: delete called with old_oid set to zeros");
1062 return ref_transaction_update(transaction, refname,
1063 &null_oid, old_oid,
1064 flags, msg, err);
1065}
1066
1067int ref_transaction_verify(struct ref_transaction *transaction,
1068 const char *refname,
1069 const struct object_id *old_oid,
1070 unsigned int flags,
1071 struct strbuf *err)
1072{
1073 if (!old_oid)
1074 die("BUG: verify called with old_oid set to NULL");
1075 return ref_transaction_update(transaction, refname,
1076 NULL, old_oid,
1077 flags, NULL, err);
1078}
1079
1080int refs_update_ref(struct ref_store *refs, const char *msg,
1081 const char *refname, const struct object_id *new_oid,
1082 const struct object_id *old_oid, unsigned int flags,
1083 enum action_on_err onerr)
1084{
1085 struct ref_transaction *t = NULL;
1086 struct strbuf err = STRBUF_INIT;
1087 int ret = 0;
1088
1089 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1090 assert(refs == get_main_ref_store(the_repository));
1091 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1092 } else {
1093 t = ref_store_transaction_begin(refs, &err);
1094 if (!t ||
1095 ref_transaction_update(t, refname, new_oid, old_oid,
1096 flags, msg, &err) ||
1097 ref_transaction_commit(t, &err)) {
1098 ret = 1;
1099 ref_transaction_free(t);
1100 }
1101 }
1102 if (ret) {
1103 const char *str = "update_ref failed for ref '%s': %s";
1104
1105 switch (onerr) {
1106 case UPDATE_REFS_MSG_ON_ERR:
1107 error(str, refname, err.buf);
1108 break;
1109 case UPDATE_REFS_DIE_ON_ERR:
1110 die(str, refname, err.buf);
1111 break;
1112 case UPDATE_REFS_QUIET_ON_ERR:
1113 break;
1114 }
1115 strbuf_release(&err);
1116 return 1;
1117 }
1118 strbuf_release(&err);
1119 if (t)
1120 ref_transaction_free(t);
1121 return 0;
1122}
1123
1124int update_ref(const char *msg, const char *refname,
1125 const struct object_id *new_oid,
1126 const struct object_id *old_oid,
1127 unsigned int flags, enum action_on_err onerr)
1128{
1129 return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid,
1130 old_oid, flags, onerr);
1131}
1132
1133char *shorten_unambiguous_ref(const char *refname, int strict)
1134{
1135 int i;
1136 static char **scanf_fmts;
1137 static int nr_rules;
1138 char *short_name;
1139 struct strbuf resolved_buf = STRBUF_INIT;
1140
1141 if (!nr_rules) {
1142 /*
1143 * Pre-generate scanf formats from ref_rev_parse_rules[].
1144 * Generate a format suitable for scanf from a
1145 * ref_rev_parse_rules rule by interpolating "%s" at the
1146 * location of the "%.*s".
1147 */
1148 size_t total_len = 0;
1149 size_t offset = 0;
1150
1151 /* the rule list is NULL terminated, count them first */
1152 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1153 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1154 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1155
1156 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1157
1158 offset = 0;
1159 for (i = 0; i < nr_rules; i++) {
1160 assert(offset < total_len);
1161 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1162 offset += snprintf(scanf_fmts[i], total_len - offset,
1163 ref_rev_parse_rules[i], 2, "%s") + 1;
1164 }
1165 }
1166
1167 /* bail out if there are no rules */
1168 if (!nr_rules)
1169 return xstrdup(refname);
1170
1171 /* buffer for scanf result, at most refname must fit */
1172 short_name = xstrdup(refname);
1173
1174 /* skip first rule, it will always match */
1175 for (i = nr_rules - 1; i > 0 ; --i) {
1176 int j;
1177 int rules_to_fail = i;
1178 int short_name_len;
1179
1180 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1181 continue;
1182
1183 short_name_len = strlen(short_name);
1184
1185 /*
1186 * in strict mode, all (except the matched one) rules
1187 * must fail to resolve to a valid non-ambiguous ref
1188 */
1189 if (strict)
1190 rules_to_fail = nr_rules;
1191
1192 /*
1193 * check if the short name resolves to a valid ref,
1194 * but use only rules prior to the matched one
1195 */
1196 for (j = 0; j < rules_to_fail; j++) {
1197 const char *rule = ref_rev_parse_rules[j];
1198
1199 /* skip matched rule */
1200 if (i == j)
1201 continue;
1202
1203 /*
1204 * the short name is ambiguous, if it resolves
1205 * (with this previous rule) to a valid ref
1206 * read_ref() returns 0 on success
1207 */
1208 strbuf_reset(&resolved_buf);
1209 strbuf_addf(&resolved_buf, rule,
1210 short_name_len, short_name);
1211 if (ref_exists(resolved_buf.buf))
1212 break;
1213 }
1214
1215 /*
1216 * short name is non-ambiguous if all previous rules
1217 * haven't resolved to a valid ref
1218 */
1219 if (j == rules_to_fail) {
1220 strbuf_release(&resolved_buf);
1221 return short_name;
1222 }
1223 }
1224
1225 strbuf_release(&resolved_buf);
1226 free(short_name);
1227 return xstrdup(refname);
1228}
1229
1230static struct string_list *hide_refs;
1231
1232int parse_hide_refs_config(const char *var, const char *value, const char *section)
1233{
1234 const char *key;
1235 if (!strcmp("transfer.hiderefs", var) ||
1236 (!parse_config_key(var, section, NULL, NULL, &key) &&
1237 !strcmp(key, "hiderefs"))) {
1238 char *ref;
1239 int len;
1240
1241 if (!value)
1242 return config_error_nonbool(var);
1243 ref = xstrdup(value);
1244 len = strlen(ref);
1245 while (len && ref[len - 1] == '/')
1246 ref[--len] = '\0';
1247 if (!hide_refs) {
1248 hide_refs = xcalloc(1, sizeof(*hide_refs));
1249 hide_refs->strdup_strings = 1;
1250 }
1251 string_list_append(hide_refs, ref);
1252 }
1253 return 0;
1254}
1255
1256int ref_is_hidden(const char *refname, const char *refname_full)
1257{
1258 int i;
1259
1260 if (!hide_refs)
1261 return 0;
1262 for (i = hide_refs->nr - 1; i >= 0; i--) {
1263 const char *match = hide_refs->items[i].string;
1264 const char *subject;
1265 int neg = 0;
1266 const char *p;
1267
1268 if (*match == '!') {
1269 neg = 1;
1270 match++;
1271 }
1272
1273 if (*match == '^') {
1274 subject = refname_full;
1275 match++;
1276 } else {
1277 subject = refname;
1278 }
1279
1280 /* refname can be NULL when namespaces are used. */
1281 if (subject &&
1282 skip_prefix(subject, match, &p) &&
1283 (!*p || *p == '/'))
1284 return !neg;
1285 }
1286 return 0;
1287}
1288
1289const char *find_descendant_ref(const char *dirname,
1290 const struct string_list *extras,
1291 const struct string_list *skip)
1292{
1293 int pos;
1294
1295 if (!extras)
1296 return NULL;
1297
1298 /*
1299 * Look at the place where dirname would be inserted into
1300 * extras. If there is an entry at that position that starts
1301 * with dirname (remember, dirname includes the trailing
1302 * slash) and is not in skip, then we have a conflict.
1303 */
1304 for (pos = string_list_find_insert_index(extras, dirname, 0);
1305 pos < extras->nr; pos++) {
1306 const char *extra_refname = extras->items[pos].string;
1307
1308 if (!starts_with(extra_refname, dirname))
1309 break;
1310
1311 if (!skip || !string_list_has_string(skip, extra_refname))
1312 return extra_refname;
1313 }
1314 return NULL;
1315}
1316
1317int refs_rename_ref_available(struct ref_store *refs,
1318 const char *old_refname,
1319 const char *new_refname)
1320{
1321 struct string_list skip = STRING_LIST_INIT_NODUP;
1322 struct strbuf err = STRBUF_INIT;
1323 int ok;
1324
1325 string_list_insert(&skip, old_refname);
1326 ok = !refs_verify_refname_available(refs, new_refname,
1327 NULL, &skip, &err);
1328 if (!ok)
1329 error("%s", err.buf);
1330
1331 string_list_clear(&skip, 0);
1332 strbuf_release(&err);
1333 return ok;
1334}
1335
1336int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1337{
1338 struct object_id oid;
1339 int flag;
1340
1341 if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1342 &oid, &flag))
1343 return fn("HEAD", &oid, flag, cb_data);
1344
1345 return 0;
1346}
1347
1348int head_ref(each_ref_fn fn, void *cb_data)
1349{
1350 return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data);
1351}
1352
1353struct ref_iterator *refs_ref_iterator_begin(
1354 struct ref_store *refs,
1355 const char *prefix, int trim, int flags)
1356{
1357 struct ref_iterator *iter;
1358
1359 if (ref_paranoia < 0)
1360 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1361 if (ref_paranoia)
1362 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1363
1364 iter = refs->be->iterator_begin(refs, prefix, flags);
1365
1366 /*
1367 * `iterator_begin()` already takes care of prefix, but we
1368 * might need to do some trimming:
1369 */
1370 if (trim)
1371 iter = prefix_ref_iterator_begin(iter, "", trim);
1372
1373 /* Sanity check for subclasses: */
1374 if (!iter->ordered)
1375 BUG("reference iterator is not ordered");
1376
1377 return iter;
1378}
1379
1380/*
1381 * Call fn for each reference in the specified submodule for which the
1382 * refname begins with prefix. If trim is non-zero, then trim that
1383 * many characters off the beginning of each refname before passing
1384 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1385 * include broken references in the iteration. If fn ever returns a
1386 * non-zero value, stop the iteration and return that value;
1387 * otherwise, return 0.
1388 */
1389static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1390 each_ref_fn fn, int trim, int flags, void *cb_data)
1391{
1392 struct ref_iterator *iter;
1393
1394 if (!refs)
1395 return 0;
1396
1397 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1398
1399 return do_for_each_ref_iterator(iter, fn, cb_data);
1400}
1401
1402int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1403{
1404 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1405}
1406
1407int for_each_ref(each_ref_fn fn, void *cb_data)
1408{
1409 return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data);
1410}
1411
1412int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1413 each_ref_fn fn, void *cb_data)
1414{
1415 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1416}
1417
1418int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1419{
1420 return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
1421}
1422
1423int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1424{
1425 unsigned int flag = 0;
1426
1427 if (broken)
1428 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1429 return do_for_each_ref(get_main_ref_store(the_repository),
1430 prefix, fn, 0, flag, cb_data);
1431}
1432
1433int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1434 each_ref_fn fn, void *cb_data,
1435 unsigned int broken)
1436{
1437 unsigned int flag = 0;
1438
1439 if (broken)
1440 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1441 return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1442}
1443
1444int for_each_replace_ref(struct repository *r, each_ref_fn fn, void *cb_data)
1445{
1446 return do_for_each_ref(get_main_ref_store(r),
1447 git_replace_ref_base, fn,
1448 strlen(git_replace_ref_base),
1449 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1450}
1451
1452int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1453{
1454 struct strbuf buf = STRBUF_INIT;
1455 int ret;
1456 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1457 ret = do_for_each_ref(get_main_ref_store(the_repository),
1458 buf.buf, fn, 0, 0, cb_data);
1459 strbuf_release(&buf);
1460 return ret;
1461}
1462
1463int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1464{
1465 return do_for_each_ref(refs, "", fn, 0,
1466 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1467}
1468
1469int for_each_rawref(each_ref_fn fn, void *cb_data)
1470{
1471 return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
1472}
1473
1474int refs_read_raw_ref(struct ref_store *ref_store,
1475 const char *refname, struct object_id *oid,
1476 struct strbuf *referent, unsigned int *type)
1477{
1478 return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1479}
1480
1481/* This function needs to return a meaningful errno on failure */
1482const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1483 const char *refname,
1484 int resolve_flags,
1485 struct object_id *oid, int *flags)
1486{
1487 static struct strbuf sb_refname = STRBUF_INIT;
1488 struct object_id unused_oid;
1489 int unused_flags;
1490 int symref_count;
1491
1492 if (!oid)
1493 oid = &unused_oid;
1494 if (!flags)
1495 flags = &unused_flags;
1496
1497 *flags = 0;
1498
1499 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1500 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1501 !refname_is_safe(refname)) {
1502 errno = EINVAL;
1503 return NULL;
1504 }
1505
1506 /*
1507 * dwim_ref() uses REF_ISBROKEN to distinguish between
1508 * missing refs and refs that were present but invalid,
1509 * to complain about the latter to stderr.
1510 *
1511 * We don't know whether the ref exists, so don't set
1512 * REF_ISBROKEN yet.
1513 */
1514 *flags |= REF_BAD_NAME;
1515 }
1516
1517 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1518 unsigned int read_flags = 0;
1519
1520 if (refs_read_raw_ref(refs, refname,
1521 oid, &sb_refname, &read_flags)) {
1522 *flags |= read_flags;
1523
1524 /* In reading mode, refs must eventually resolve */
1525 if (resolve_flags & RESOLVE_REF_READING)
1526 return NULL;
1527
1528 /*
1529 * Otherwise a missing ref is OK. But the files backend
1530 * may show errors besides ENOENT if there are
1531 * similarly-named refs.
1532 */
1533 if (errno != ENOENT &&
1534 errno != EISDIR &&
1535 errno != ENOTDIR)
1536 return NULL;
1537
1538 oidclr(oid);
1539 if (*flags & REF_BAD_NAME)
1540 *flags |= REF_ISBROKEN;
1541 return refname;
1542 }
1543
1544 *flags |= read_flags;
1545
1546 if (!(read_flags & REF_ISSYMREF)) {
1547 if (*flags & REF_BAD_NAME) {
1548 oidclr(oid);
1549 *flags |= REF_ISBROKEN;
1550 }
1551 return refname;
1552 }
1553
1554 refname = sb_refname.buf;
1555 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1556 oidclr(oid);
1557 return refname;
1558 }
1559 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1560 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1561 !refname_is_safe(refname)) {
1562 errno = EINVAL;
1563 return NULL;
1564 }
1565
1566 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1567 }
1568 }
1569
1570 errno = ELOOP;
1571 return NULL;
1572}
1573
1574/* backend functions */
1575int refs_init_db(struct strbuf *err)
1576{
1577 struct ref_store *refs = get_main_ref_store(the_repository);
1578
1579 return refs->be->init_db(refs, err);
1580}
1581
1582const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1583 struct object_id *oid, int *flags)
1584{
1585 return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname,
1586 resolve_flags, oid, flags);
1587}
1588
1589int resolve_gitlink_ref(const char *submodule, const char *refname,
1590 struct object_id *oid)
1591{
1592 struct ref_store *refs;
1593 int flags;
1594
1595 refs = get_submodule_ref_store(submodule);
1596
1597 if (!refs)
1598 return -1;
1599
1600 if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1601 is_null_oid(oid))
1602 return -1;
1603 return 0;
1604}
1605
1606struct ref_store_hash_entry
1607{
1608 struct hashmap_entry ent; /* must be the first member! */
1609
1610 struct ref_store *refs;
1611
1612 /* NUL-terminated identifier of the ref store: */
1613 char name[FLEX_ARRAY];
1614};
1615
1616static int ref_store_hash_cmp(const void *unused_cmp_data,
1617 const void *entry, const void *entry_or_key,
1618 const void *keydata)
1619{
1620 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1621 const char *name = keydata ? keydata : e2->name;
1622
1623 return strcmp(e1->name, name);
1624}
1625
1626static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1627 const char *name, struct ref_store *refs)
1628{
1629 struct ref_store_hash_entry *entry;
1630
1631 FLEX_ALLOC_STR(entry, name, name);
1632 hashmap_entry_init(entry, strhash(name));
1633 entry->refs = refs;
1634 return entry;
1635}
1636
1637/* A hashmap of ref_stores, stored by submodule name: */
1638static struct hashmap submodule_ref_stores;
1639
1640/* A hashmap of ref_stores, stored by worktree id: */
1641static struct hashmap worktree_ref_stores;
1642
1643/*
1644 * Look up a ref store by name. If that ref_store hasn't been
1645 * registered yet, return NULL.
1646 */
1647static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1648 const char *name)
1649{
1650 struct ref_store_hash_entry *entry;
1651
1652 if (!map->tablesize)
1653 /* It's initialized on demand in register_ref_store(). */
1654 return NULL;
1655
1656 entry = hashmap_get_from_hash(map, strhash(name), name);
1657 return entry ? entry->refs : NULL;
1658}
1659
1660/*
1661 * Create, record, and return a ref_store instance for the specified
1662 * gitdir.
1663 */
1664static struct ref_store *ref_store_init(const char *gitdir,
1665 unsigned int flags)
1666{
1667 const char *be_name = "files";
1668 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1669 struct ref_store *refs;
1670
1671 if (!be)
1672 die("BUG: reference backend %s is unknown", be_name);
1673
1674 refs = be->init(gitdir, flags);
1675 return refs;
1676}
1677
1678struct ref_store *get_main_ref_store(struct repository *r)
1679{
1680 if (r->refs)
1681 return r->refs;
1682
1683 r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
1684 return r->refs;
1685}
1686
1687/*
1688 * Associate a ref store with a name. It is a fatal error to call this
1689 * function twice for the same name.
1690 */
1691static void register_ref_store_map(struct hashmap *map,
1692 const char *type,
1693 struct ref_store *refs,
1694 const char *name)
1695{
1696 if (!map->tablesize)
1697 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1698
1699 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1700 die("BUG: %s ref_store '%s' initialized twice", type, name);
1701}
1702
1703struct ref_store *get_submodule_ref_store(const char *submodule)
1704{
1705 struct strbuf submodule_sb = STRBUF_INIT;
1706 struct ref_store *refs;
1707 char *to_free = NULL;
1708 size_t len;
1709
1710 if (!submodule)
1711 return NULL;
1712
1713 len = strlen(submodule);
1714 while (len && is_dir_sep(submodule[len - 1]))
1715 len--;
1716 if (!len)
1717 return NULL;
1718
1719 if (submodule[len])
1720 /* We need to strip off one or more trailing slashes */
1721 submodule = to_free = xmemdupz(submodule, len);
1722
1723 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1724 if (refs)
1725 goto done;
1726
1727 strbuf_addstr(&submodule_sb, submodule);
1728 if (!is_nonbare_repository_dir(&submodule_sb))
1729 goto done;
1730
1731 if (submodule_to_gitdir(&submodule_sb, submodule))
1732 goto done;
1733
1734 /* assume that add_submodule_odb() has been called */
1735 refs = ref_store_init(submodule_sb.buf,
1736 REF_STORE_READ | REF_STORE_ODB);
1737 register_ref_store_map(&submodule_ref_stores, "submodule",
1738 refs, submodule);
1739
1740done:
1741 strbuf_release(&submodule_sb);
1742 free(to_free);
1743
1744 return refs;
1745}
1746
1747struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1748{
1749 struct ref_store *refs;
1750 const char *id;
1751
1752 if (wt->is_current)
1753 return get_main_ref_store(the_repository);
1754
1755 id = wt->id ? wt->id : "/";
1756 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1757 if (refs)
1758 return refs;
1759
1760 if (wt->id)
1761 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1762 REF_STORE_ALL_CAPS);
1763 else
1764 refs = ref_store_init(get_git_common_dir(),
1765 REF_STORE_ALL_CAPS);
1766
1767 if (refs)
1768 register_ref_store_map(&worktree_ref_stores, "worktree",
1769 refs, id);
1770 return refs;
1771}
1772
1773void base_ref_store_init(struct ref_store *refs,
1774 const struct ref_storage_be *be)
1775{
1776 refs->be = be;
1777}
1778
1779/* backend functions */
1780int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1781{
1782 return refs->be->pack_refs(refs, flags);
1783}
1784
1785int refs_peel_ref(struct ref_store *refs, const char *refname,
1786 struct object_id *oid)
1787{
1788 int flag;
1789 struct object_id base;
1790
1791 if (current_ref_iter && current_ref_iter->refname == refname) {
1792 struct object_id peeled;
1793
1794 if (ref_iterator_peel(current_ref_iter, &peeled))
1795 return -1;
1796 oidcpy(oid, &peeled);
1797 return 0;
1798 }
1799
1800 if (refs_read_ref_full(refs, refname,
1801 RESOLVE_REF_READING, &base, &flag))
1802 return -1;
1803
1804 return peel_object(&base, oid);
1805}
1806
1807int peel_ref(const char *refname, struct object_id *oid)
1808{
1809 return refs_peel_ref(get_main_ref_store(the_repository), refname, oid);
1810}
1811
1812int refs_create_symref(struct ref_store *refs,
1813 const char *ref_target,
1814 const char *refs_heads_master,
1815 const char *logmsg)
1816{
1817 return refs->be->create_symref(refs, ref_target,
1818 refs_heads_master,
1819 logmsg);
1820}
1821
1822int create_symref(const char *ref_target, const char *refs_heads_master,
1823 const char *logmsg)
1824{
1825 return refs_create_symref(get_main_ref_store(the_repository), ref_target,
1826 refs_heads_master, logmsg);
1827}
1828
1829int ref_update_reject_duplicates(struct string_list *refnames,
1830 struct strbuf *err)
1831{
1832 size_t i, n = refnames->nr;
1833
1834 assert(err);
1835
1836 for (i = 1; i < n; i++) {
1837 int cmp = strcmp(refnames->items[i - 1].string,
1838 refnames->items[i].string);
1839
1840 if (!cmp) {
1841 strbuf_addf(err,
1842 "multiple updates for ref '%s' not allowed.",
1843 refnames->items[i].string);
1844 return 1;
1845 } else if (cmp > 0) {
1846 die("BUG: ref_update_reject_duplicates() received unsorted list");
1847 }
1848 }
1849 return 0;
1850}
1851
1852int ref_transaction_prepare(struct ref_transaction *transaction,
1853 struct strbuf *err)
1854{
1855 struct ref_store *refs = transaction->ref_store;
1856
1857 switch (transaction->state) {
1858 case REF_TRANSACTION_OPEN:
1859 /* Good. */
1860 break;
1861 case REF_TRANSACTION_PREPARED:
1862 die("BUG: prepare called twice on reference transaction");
1863 break;
1864 case REF_TRANSACTION_CLOSED:
1865 die("BUG: prepare called on a closed reference transaction");
1866 break;
1867 default:
1868 die("BUG: unexpected reference transaction state");
1869 break;
1870 }
1871
1872 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1873 strbuf_addstr(err,
1874 _("ref updates forbidden inside quarantine environment"));
1875 return -1;
1876 }
1877
1878 return refs->be->transaction_prepare(refs, transaction, err);
1879}
1880
1881int ref_transaction_abort(struct ref_transaction *transaction,
1882 struct strbuf *err)
1883{
1884 struct ref_store *refs = transaction->ref_store;
1885 int ret = 0;
1886
1887 switch (transaction->state) {
1888 case REF_TRANSACTION_OPEN:
1889 /* No need to abort explicitly. */
1890 break;
1891 case REF_TRANSACTION_PREPARED:
1892 ret = refs->be->transaction_abort(refs, transaction, err);
1893 break;
1894 case REF_TRANSACTION_CLOSED:
1895 die("BUG: abort called on a closed reference transaction");
1896 break;
1897 default:
1898 die("BUG: unexpected reference transaction state");
1899 break;
1900 }
1901
1902 ref_transaction_free(transaction);
1903 return ret;
1904}
1905
1906int ref_transaction_commit(struct ref_transaction *transaction,
1907 struct strbuf *err)
1908{
1909 struct ref_store *refs = transaction->ref_store;
1910 int ret;
1911
1912 switch (transaction->state) {
1913 case REF_TRANSACTION_OPEN:
1914 /* Need to prepare first. */
1915 ret = ref_transaction_prepare(transaction, err);
1916 if (ret)
1917 return ret;
1918 break;
1919 case REF_TRANSACTION_PREPARED:
1920 /* Fall through to finish. */
1921 break;
1922 case REF_TRANSACTION_CLOSED:
1923 die("BUG: commit called on a closed reference transaction");
1924 break;
1925 default:
1926 die("BUG: unexpected reference transaction state");
1927 break;
1928 }
1929
1930 return refs->be->transaction_finish(refs, transaction, err);
1931}
1932
1933int refs_verify_refname_available(struct ref_store *refs,
1934 const char *refname,
1935 const struct string_list *extras,
1936 const struct string_list *skip,
1937 struct strbuf *err)
1938{
1939 const char *slash;
1940 const char *extra_refname;
1941 struct strbuf dirname = STRBUF_INIT;
1942 struct strbuf referent = STRBUF_INIT;
1943 struct object_id oid;
1944 unsigned int type;
1945 struct ref_iterator *iter;
1946 int ok;
1947 int ret = -1;
1948
1949 /*
1950 * For the sake of comments in this function, suppose that
1951 * refname is "refs/foo/bar".
1952 */
1953
1954 assert(err);
1955
1956 strbuf_grow(&dirname, strlen(refname) + 1);
1957 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1958 /* Expand dirname to the new prefix, not including the trailing slash: */
1959 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1960
1961 /*
1962 * We are still at a leading dir of the refname (e.g.,
1963 * "refs/foo"; if there is a reference with that name,
1964 * it is a conflict, *unless* it is in skip.
1965 */
1966 if (skip && string_list_has_string(skip, dirname.buf))
1967 continue;
1968
1969 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
1970 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1971 dirname.buf, refname);
1972 goto cleanup;
1973 }
1974
1975 if (extras && string_list_has_string(extras, dirname.buf)) {
1976 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1977 refname, dirname.buf);
1978 goto cleanup;
1979 }
1980 }
1981
1982 /*
1983 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1984 * There is no point in searching for a reference with that
1985 * name, because a refname isn't considered to conflict with
1986 * itself. But we still need to check for references whose
1987 * names are in the "refs/foo/bar/" namespace, because they
1988 * *do* conflict.
1989 */
1990 strbuf_addstr(&dirname, refname + dirname.len);
1991 strbuf_addch(&dirname, '/');
1992
1993 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
1994 DO_FOR_EACH_INCLUDE_BROKEN);
1995 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
1996 if (skip &&
1997 string_list_has_string(skip, iter->refname))
1998 continue;
1999
2000 strbuf_addf(err, "'%s' exists; cannot create '%s'",
2001 iter->refname, refname);
2002 ref_iterator_abort(iter);
2003 goto cleanup;
2004 }
2005
2006 if (ok != ITER_DONE)
2007 die("BUG: error while iterating over references");
2008
2009 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
2010 if (extra_refname)
2011 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
2012 refname, extra_refname);
2013 else
2014 ret = 0;
2015
2016cleanup:
2017 strbuf_release(&referent);
2018 strbuf_release(&dirname);
2019 return ret;
2020}
2021
2022int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2023{
2024 struct ref_iterator *iter;
2025
2026 iter = refs->be->reflog_iterator_begin(refs);
2027
2028 return do_for_each_ref_iterator(iter, fn, cb_data);
2029}
2030
2031int for_each_reflog(each_ref_fn fn, void *cb_data)
2032{
2033 return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
2034}
2035
2036int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
2037 const char *refname,
2038 each_reflog_ent_fn fn,
2039 void *cb_data)
2040{
2041 return refs->be->for_each_reflog_ent_reverse(refs, refname,
2042 fn, cb_data);
2043}
2044
2045int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
2046 void *cb_data)
2047{
2048 return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository),
2049 refname, fn, cb_data);
2050}
2051
2052int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
2053 each_reflog_ent_fn fn, void *cb_data)
2054{
2055 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
2056}
2057
2058int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
2059 void *cb_data)
2060{
2061 return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname,
2062 fn, cb_data);
2063}
2064
2065int refs_reflog_exists(struct ref_store *refs, const char *refname)
2066{
2067 return refs->be->reflog_exists(refs, refname);
2068}
2069
2070int reflog_exists(const char *refname)
2071{
2072 return refs_reflog_exists(get_main_ref_store(the_repository), refname);
2073}
2074
2075int refs_create_reflog(struct ref_store *refs, const char *refname,
2076 int force_create, struct strbuf *err)
2077{
2078 return refs->be->create_reflog(refs, refname, force_create, err);
2079}
2080
2081int safe_create_reflog(const char *refname, int force_create,
2082 struct strbuf *err)
2083{
2084 return refs_create_reflog(get_main_ref_store(the_repository), refname,
2085 force_create, err);
2086}
2087
2088int refs_delete_reflog(struct ref_store *refs, const char *refname)
2089{
2090 return refs->be->delete_reflog(refs, refname);
2091}
2092
2093int delete_reflog(const char *refname)
2094{
2095 return refs_delete_reflog(get_main_ref_store(the_repository), refname);
2096}
2097
2098int refs_reflog_expire(struct ref_store *refs,
2099 const char *refname, const struct object_id *oid,
2100 unsigned int flags,
2101 reflog_expiry_prepare_fn prepare_fn,
2102 reflog_expiry_should_prune_fn should_prune_fn,
2103 reflog_expiry_cleanup_fn cleanup_fn,
2104 void *policy_cb_data)
2105{
2106 return refs->be->reflog_expire(refs, refname, oid, flags,
2107 prepare_fn, should_prune_fn,
2108 cleanup_fn, policy_cb_data);
2109}
2110
2111int reflog_expire(const char *refname, const struct object_id *oid,
2112 unsigned int flags,
2113 reflog_expiry_prepare_fn prepare_fn,
2114 reflog_expiry_should_prune_fn should_prune_fn,
2115 reflog_expiry_cleanup_fn cleanup_fn,
2116 void *policy_cb_data)
2117{
2118 return refs_reflog_expire(get_main_ref_store(the_repository),
2119 refname, oid, flags,
2120 prepare_fn, should_prune_fn,
2121 cleanup_fn, policy_cb_data);
2122}
2123
2124int initial_ref_transaction_commit(struct ref_transaction *transaction,
2125 struct strbuf *err)
2126{
2127 struct ref_store *refs = transaction->ref_store;
2128
2129 return refs->be->initial_transaction_commit(refs, transaction, err);
2130}
2131
2132int refs_delete_refs(struct ref_store *refs, const char *msg,
2133 struct string_list *refnames, unsigned int flags)
2134{
2135 return refs->be->delete_refs(refs, msg, refnames, flags);
2136}
2137
2138int delete_refs(const char *msg, struct string_list *refnames,
2139 unsigned int flags)
2140{
2141 return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags);
2142}
2143
2144int refs_rename_ref(struct ref_store *refs, const char *oldref,
2145 const char *newref, const char *logmsg)
2146{
2147 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2148}
2149
2150int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2151{
2152 return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2153}
2154
2155int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2156 const char *newref, const char *logmsg)
2157{
2158 return refs->be->copy_ref(refs, oldref, newref, logmsg);
2159}
2160
2161int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2162{
2163 return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2164}