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 die("could not read ref '%s'", pseudoref);
686 if (oidcmp(&actual_old_oid, old_oid)) {
687 strbuf_addf(err, "unexpected object ID when writing '%s'",
688 pseudoref);
689 rollback_lock_file(&lock);
690 goto done;
691 }
692 }
693
694 if (write_in_full(fd, buf.buf, buf.len) < 0) {
695 strbuf_addf(err, "could not write to '%s'", filename);
696 rollback_lock_file(&lock);
697 goto done;
698 }
699
700 commit_lock_file(&lock);
701 ret = 0;
702done:
703 strbuf_release(&buf);
704 return ret;
705}
706
707static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
708{
709 static struct lock_file lock;
710 const char *filename;
711
712 filename = git_path("%s", pseudoref);
713
714 if (old_oid && !is_null_oid(old_oid)) {
715 int fd;
716 struct object_id actual_old_oid;
717
718 fd = hold_lock_file_for_update_timeout(
719 &lock, filename, LOCK_DIE_ON_ERROR,
720 get_files_ref_lock_timeout_ms());
721 if (fd < 0)
722 die_errno(_("Could not open '%s' for writing"), filename);
723 if (read_ref(pseudoref, &actual_old_oid))
724 die("could not read ref '%s'", pseudoref);
725 if (oidcmp(&actual_old_oid, old_oid)) {
726 error("unexpected object ID when deleting '%s'",
727 pseudoref);
728 rollback_lock_file(&lock);
729 return -1;
730 }
731
732 unlink(filename);
733 rollback_lock_file(&lock);
734 } else {
735 unlink(filename);
736 }
737
738 return 0;
739}
740
741int refs_delete_ref(struct ref_store *refs, const char *msg,
742 const char *refname,
743 const struct object_id *old_oid,
744 unsigned int flags)
745{
746 struct ref_transaction *transaction;
747 struct strbuf err = STRBUF_INIT;
748
749 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
750 assert(refs == get_main_ref_store(the_repository));
751 return delete_pseudoref(refname, old_oid);
752 }
753
754 transaction = ref_store_transaction_begin(refs, &err);
755 if (!transaction ||
756 ref_transaction_delete(transaction, refname, old_oid,
757 flags, msg, &err) ||
758 ref_transaction_commit(transaction, &err)) {
759 error("%s", err.buf);
760 ref_transaction_free(transaction);
761 strbuf_release(&err);
762 return 1;
763 }
764 ref_transaction_free(transaction);
765 strbuf_release(&err);
766 return 0;
767}
768
769int delete_ref(const char *msg, const char *refname,
770 const struct object_id *old_oid, unsigned int flags)
771{
772 return refs_delete_ref(get_main_ref_store(the_repository), msg, refname,
773 old_oid, flags);
774}
775
776int copy_reflog_msg(char *buf, const char *msg)
777{
778 char *cp = buf;
779 char c;
780 int wasspace = 1;
781
782 *cp++ = '\t';
783 while ((c = *msg++)) {
784 if (wasspace && isspace(c))
785 continue;
786 wasspace = isspace(c);
787 if (wasspace)
788 c = ' ';
789 *cp++ = c;
790 }
791 while (buf < cp && isspace(cp[-1]))
792 cp--;
793 *cp++ = '\n';
794 return cp - buf;
795}
796
797int should_autocreate_reflog(const char *refname)
798{
799 switch (log_all_ref_updates) {
800 case LOG_REFS_ALWAYS:
801 return 1;
802 case LOG_REFS_NORMAL:
803 return starts_with(refname, "refs/heads/") ||
804 starts_with(refname, "refs/remotes/") ||
805 starts_with(refname, "refs/notes/") ||
806 !strcmp(refname, "HEAD");
807 default:
808 return 0;
809 }
810}
811
812int is_branch(const char *refname)
813{
814 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
815}
816
817struct read_ref_at_cb {
818 const char *refname;
819 timestamp_t at_time;
820 int cnt;
821 int reccnt;
822 struct object_id *oid;
823 int found_it;
824
825 struct object_id ooid;
826 struct object_id noid;
827 int tz;
828 timestamp_t date;
829 char **msg;
830 timestamp_t *cutoff_time;
831 int *cutoff_tz;
832 int *cutoff_cnt;
833};
834
835static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
836 const char *email, timestamp_t timestamp, int tz,
837 const char *message, void *cb_data)
838{
839 struct read_ref_at_cb *cb = cb_data;
840
841 cb->reccnt++;
842 cb->tz = tz;
843 cb->date = timestamp;
844
845 if (timestamp <= cb->at_time || cb->cnt == 0) {
846 if (cb->msg)
847 *cb->msg = xstrdup(message);
848 if (cb->cutoff_time)
849 *cb->cutoff_time = timestamp;
850 if (cb->cutoff_tz)
851 *cb->cutoff_tz = tz;
852 if (cb->cutoff_cnt)
853 *cb->cutoff_cnt = cb->reccnt - 1;
854 /*
855 * we have not yet updated cb->[n|o]oid so they still
856 * hold the values for the previous record.
857 */
858 if (!is_null_oid(&cb->ooid)) {
859 oidcpy(cb->oid, noid);
860 if (oidcmp(&cb->ooid, noid))
861 warning("Log for ref %s has gap after %s.",
862 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
863 }
864 else if (cb->date == cb->at_time)
865 oidcpy(cb->oid, noid);
866 else if (oidcmp(noid, cb->oid))
867 warning("Log for ref %s unexpectedly ended on %s.",
868 cb->refname, show_date(cb->date, cb->tz,
869 DATE_MODE(RFC2822)));
870 oidcpy(&cb->ooid, ooid);
871 oidcpy(&cb->noid, noid);
872 cb->found_it = 1;
873 return 1;
874 }
875 oidcpy(&cb->ooid, ooid);
876 oidcpy(&cb->noid, noid);
877 if (cb->cnt > 0)
878 cb->cnt--;
879 return 0;
880}
881
882static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
883 const char *email, timestamp_t timestamp,
884 int tz, const char *message, void *cb_data)
885{
886 struct read_ref_at_cb *cb = cb_data;
887
888 if (cb->msg)
889 *cb->msg = xstrdup(message);
890 if (cb->cutoff_time)
891 *cb->cutoff_time = timestamp;
892 if (cb->cutoff_tz)
893 *cb->cutoff_tz = tz;
894 if (cb->cutoff_cnt)
895 *cb->cutoff_cnt = cb->reccnt;
896 oidcpy(cb->oid, ooid);
897 if (is_null_oid(cb->oid))
898 oidcpy(cb->oid, noid);
899 /* We just want the first entry */
900 return 1;
901}
902
903int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
904 struct object_id *oid, char **msg,
905 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
906{
907 struct read_ref_at_cb cb;
908
909 memset(&cb, 0, sizeof(cb));
910 cb.refname = refname;
911 cb.at_time = at_time;
912 cb.cnt = cnt;
913 cb.msg = msg;
914 cb.cutoff_time = cutoff_time;
915 cb.cutoff_tz = cutoff_tz;
916 cb.cutoff_cnt = cutoff_cnt;
917 cb.oid = oid;
918
919 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
920
921 if (!cb.reccnt) {
922 if (flags & GET_OID_QUIETLY)
923 exit(128);
924 else
925 die("Log for %s is empty.", refname);
926 }
927 if (cb.found_it)
928 return 0;
929
930 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
931
932 return 1;
933}
934
935struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
936 struct strbuf *err)
937{
938 struct ref_transaction *tr;
939 assert(err);
940
941 tr = xcalloc(1, sizeof(struct ref_transaction));
942 tr->ref_store = refs;
943 return tr;
944}
945
946struct ref_transaction *ref_transaction_begin(struct strbuf *err)
947{
948 return ref_store_transaction_begin(get_main_ref_store(the_repository), err);
949}
950
951void ref_transaction_free(struct ref_transaction *transaction)
952{
953 size_t i;
954
955 if (!transaction)
956 return;
957
958 switch (transaction->state) {
959 case REF_TRANSACTION_OPEN:
960 case REF_TRANSACTION_CLOSED:
961 /* OK */
962 break;
963 case REF_TRANSACTION_PREPARED:
964 die("BUG: free called on a prepared reference transaction");
965 break;
966 default:
967 die("BUG: unexpected reference transaction state");
968 break;
969 }
970
971 for (i = 0; i < transaction->nr; i++) {
972 free(transaction->updates[i]->msg);
973 free(transaction->updates[i]);
974 }
975 free(transaction->updates);
976 free(transaction);
977}
978
979struct ref_update *ref_transaction_add_update(
980 struct ref_transaction *transaction,
981 const char *refname, unsigned int flags,
982 const struct object_id *new_oid,
983 const struct object_id *old_oid,
984 const char *msg)
985{
986 struct ref_update *update;
987
988 if (transaction->state != REF_TRANSACTION_OPEN)
989 die("BUG: update called for transaction that is not open");
990
991 FLEX_ALLOC_STR(update, refname, refname);
992 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
993 transaction->updates[transaction->nr++] = update;
994
995 update->flags = flags;
996
997 if (flags & REF_HAVE_NEW)
998 oidcpy(&update->new_oid, new_oid);
999 if (flags & REF_HAVE_OLD)
1000 oidcpy(&update->old_oid, old_oid);
1001 update->msg = xstrdup_or_null(msg);
1002 return update;
1003}
1004
1005int ref_transaction_update(struct ref_transaction *transaction,
1006 const char *refname,
1007 const struct object_id *new_oid,
1008 const struct object_id *old_oid,
1009 unsigned int flags, const char *msg,
1010 struct strbuf *err)
1011{
1012 assert(err);
1013
1014 if ((new_oid && !is_null_oid(new_oid)) ?
1015 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
1016 !refname_is_safe(refname)) {
1017 strbuf_addf(err, "refusing to update ref with bad name '%s'",
1018 refname);
1019 return -1;
1020 }
1021
1022 if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
1023 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
1024
1025 flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
1026
1027 ref_transaction_add_update(transaction, refname, flags,
1028 new_oid, old_oid, msg);
1029 return 0;
1030}
1031
1032int ref_transaction_create(struct ref_transaction *transaction,
1033 const char *refname,
1034 const struct object_id *new_oid,
1035 unsigned int flags, const char *msg,
1036 struct strbuf *err)
1037{
1038 if (!new_oid || is_null_oid(new_oid))
1039 die("BUG: create called without valid new_oid");
1040 return ref_transaction_update(transaction, refname, new_oid,
1041 &null_oid, flags, msg, err);
1042}
1043
1044int ref_transaction_delete(struct ref_transaction *transaction,
1045 const char *refname,
1046 const struct object_id *old_oid,
1047 unsigned int flags, const char *msg,
1048 struct strbuf *err)
1049{
1050 if (old_oid && is_null_oid(old_oid))
1051 die("BUG: delete called with old_oid set to zeros");
1052 return ref_transaction_update(transaction, refname,
1053 &null_oid, old_oid,
1054 flags, msg, err);
1055}
1056
1057int ref_transaction_verify(struct ref_transaction *transaction,
1058 const char *refname,
1059 const struct object_id *old_oid,
1060 unsigned int flags,
1061 struct strbuf *err)
1062{
1063 if (!old_oid)
1064 die("BUG: verify called with old_oid set to NULL");
1065 return ref_transaction_update(transaction, refname,
1066 NULL, old_oid,
1067 flags, NULL, err);
1068}
1069
1070int refs_update_ref(struct ref_store *refs, const char *msg,
1071 const char *refname, const struct object_id *new_oid,
1072 const struct object_id *old_oid, unsigned int flags,
1073 enum action_on_err onerr)
1074{
1075 struct ref_transaction *t = NULL;
1076 struct strbuf err = STRBUF_INIT;
1077 int ret = 0;
1078
1079 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1080 assert(refs == get_main_ref_store(the_repository));
1081 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1082 } else {
1083 t = ref_store_transaction_begin(refs, &err);
1084 if (!t ||
1085 ref_transaction_update(t, refname, new_oid, old_oid,
1086 flags, msg, &err) ||
1087 ref_transaction_commit(t, &err)) {
1088 ret = 1;
1089 ref_transaction_free(t);
1090 }
1091 }
1092 if (ret) {
1093 const char *str = "update_ref failed for ref '%s': %s";
1094
1095 switch (onerr) {
1096 case UPDATE_REFS_MSG_ON_ERR:
1097 error(str, refname, err.buf);
1098 break;
1099 case UPDATE_REFS_DIE_ON_ERR:
1100 die(str, refname, err.buf);
1101 break;
1102 case UPDATE_REFS_QUIET_ON_ERR:
1103 break;
1104 }
1105 strbuf_release(&err);
1106 return 1;
1107 }
1108 strbuf_release(&err);
1109 if (t)
1110 ref_transaction_free(t);
1111 return 0;
1112}
1113
1114int update_ref(const char *msg, const char *refname,
1115 const struct object_id *new_oid,
1116 const struct object_id *old_oid,
1117 unsigned int flags, enum action_on_err onerr)
1118{
1119 return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid,
1120 old_oid, flags, onerr);
1121}
1122
1123char *shorten_unambiguous_ref(const char *refname, int strict)
1124{
1125 int i;
1126 static char **scanf_fmts;
1127 static int nr_rules;
1128 char *short_name;
1129 struct strbuf resolved_buf = STRBUF_INIT;
1130
1131 if (!nr_rules) {
1132 /*
1133 * Pre-generate scanf formats from ref_rev_parse_rules[].
1134 * Generate a format suitable for scanf from a
1135 * ref_rev_parse_rules rule by interpolating "%s" at the
1136 * location of the "%.*s".
1137 */
1138 size_t total_len = 0;
1139 size_t offset = 0;
1140
1141 /* the rule list is NULL terminated, count them first */
1142 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1143 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1144 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1145
1146 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1147
1148 offset = 0;
1149 for (i = 0; i < nr_rules; i++) {
1150 assert(offset < total_len);
1151 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1152 offset += snprintf(scanf_fmts[i], total_len - offset,
1153 ref_rev_parse_rules[i], 2, "%s") + 1;
1154 }
1155 }
1156
1157 /* bail out if there are no rules */
1158 if (!nr_rules)
1159 return xstrdup(refname);
1160
1161 /* buffer for scanf result, at most refname must fit */
1162 short_name = xstrdup(refname);
1163
1164 /* skip first rule, it will always match */
1165 for (i = nr_rules - 1; i > 0 ; --i) {
1166 int j;
1167 int rules_to_fail = i;
1168 int short_name_len;
1169
1170 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1171 continue;
1172
1173 short_name_len = strlen(short_name);
1174
1175 /*
1176 * in strict mode, all (except the matched one) rules
1177 * must fail to resolve to a valid non-ambiguous ref
1178 */
1179 if (strict)
1180 rules_to_fail = nr_rules;
1181
1182 /*
1183 * check if the short name resolves to a valid ref,
1184 * but use only rules prior to the matched one
1185 */
1186 for (j = 0; j < rules_to_fail; j++) {
1187 const char *rule = ref_rev_parse_rules[j];
1188
1189 /* skip matched rule */
1190 if (i == j)
1191 continue;
1192
1193 /*
1194 * the short name is ambiguous, if it resolves
1195 * (with this previous rule) to a valid ref
1196 * read_ref() returns 0 on success
1197 */
1198 strbuf_reset(&resolved_buf);
1199 strbuf_addf(&resolved_buf, rule,
1200 short_name_len, short_name);
1201 if (ref_exists(resolved_buf.buf))
1202 break;
1203 }
1204
1205 /*
1206 * short name is non-ambiguous if all previous rules
1207 * haven't resolved to a valid ref
1208 */
1209 if (j == rules_to_fail) {
1210 strbuf_release(&resolved_buf);
1211 return short_name;
1212 }
1213 }
1214
1215 strbuf_release(&resolved_buf);
1216 free(short_name);
1217 return xstrdup(refname);
1218}
1219
1220static struct string_list *hide_refs;
1221
1222int parse_hide_refs_config(const char *var, const char *value, const char *section)
1223{
1224 const char *key;
1225 if (!strcmp("transfer.hiderefs", var) ||
1226 (!parse_config_key(var, section, NULL, NULL, &key) &&
1227 !strcmp(key, "hiderefs"))) {
1228 char *ref;
1229 int len;
1230
1231 if (!value)
1232 return config_error_nonbool(var);
1233 ref = xstrdup(value);
1234 len = strlen(ref);
1235 while (len && ref[len - 1] == '/')
1236 ref[--len] = '\0';
1237 if (!hide_refs) {
1238 hide_refs = xcalloc(1, sizeof(*hide_refs));
1239 hide_refs->strdup_strings = 1;
1240 }
1241 string_list_append(hide_refs, ref);
1242 }
1243 return 0;
1244}
1245
1246int ref_is_hidden(const char *refname, const char *refname_full)
1247{
1248 int i;
1249
1250 if (!hide_refs)
1251 return 0;
1252 for (i = hide_refs->nr - 1; i >= 0; i--) {
1253 const char *match = hide_refs->items[i].string;
1254 const char *subject;
1255 int neg = 0;
1256 const char *p;
1257
1258 if (*match == '!') {
1259 neg = 1;
1260 match++;
1261 }
1262
1263 if (*match == '^') {
1264 subject = refname_full;
1265 match++;
1266 } else {
1267 subject = refname;
1268 }
1269
1270 /* refname can be NULL when namespaces are used. */
1271 if (subject &&
1272 skip_prefix(subject, match, &p) &&
1273 (!*p || *p == '/'))
1274 return !neg;
1275 }
1276 return 0;
1277}
1278
1279const char *find_descendant_ref(const char *dirname,
1280 const struct string_list *extras,
1281 const struct string_list *skip)
1282{
1283 int pos;
1284
1285 if (!extras)
1286 return NULL;
1287
1288 /*
1289 * Look at the place where dirname would be inserted into
1290 * extras. If there is an entry at that position that starts
1291 * with dirname (remember, dirname includes the trailing
1292 * slash) and is not in skip, then we have a conflict.
1293 */
1294 for (pos = string_list_find_insert_index(extras, dirname, 0);
1295 pos < extras->nr; pos++) {
1296 const char *extra_refname = extras->items[pos].string;
1297
1298 if (!starts_with(extra_refname, dirname))
1299 break;
1300
1301 if (!skip || !string_list_has_string(skip, extra_refname))
1302 return extra_refname;
1303 }
1304 return NULL;
1305}
1306
1307int refs_rename_ref_available(struct ref_store *refs,
1308 const char *old_refname,
1309 const char *new_refname)
1310{
1311 struct string_list skip = STRING_LIST_INIT_NODUP;
1312 struct strbuf err = STRBUF_INIT;
1313 int ok;
1314
1315 string_list_insert(&skip, old_refname);
1316 ok = !refs_verify_refname_available(refs, new_refname,
1317 NULL, &skip, &err);
1318 if (!ok)
1319 error("%s", err.buf);
1320
1321 string_list_clear(&skip, 0);
1322 strbuf_release(&err);
1323 return ok;
1324}
1325
1326int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1327{
1328 struct object_id oid;
1329 int flag;
1330
1331 if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1332 &oid, &flag))
1333 return fn("HEAD", &oid, flag, cb_data);
1334
1335 return 0;
1336}
1337
1338int head_ref(each_ref_fn fn, void *cb_data)
1339{
1340 return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data);
1341}
1342
1343struct ref_iterator *refs_ref_iterator_begin(
1344 struct ref_store *refs,
1345 const char *prefix, int trim, int flags)
1346{
1347 struct ref_iterator *iter;
1348
1349 if (ref_paranoia < 0)
1350 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1351 if (ref_paranoia)
1352 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1353
1354 iter = refs->be->iterator_begin(refs, prefix, flags);
1355
1356 /*
1357 * `iterator_begin()` already takes care of prefix, but we
1358 * might need to do some trimming:
1359 */
1360 if (trim)
1361 iter = prefix_ref_iterator_begin(iter, "", trim);
1362
1363 /* Sanity check for subclasses: */
1364 if (!iter->ordered)
1365 BUG("reference iterator is not ordered");
1366
1367 return iter;
1368}
1369
1370/*
1371 * Call fn for each reference in the specified submodule for which the
1372 * refname begins with prefix. If trim is non-zero, then trim that
1373 * many characters off the beginning of each refname before passing
1374 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1375 * include broken references in the iteration. If fn ever returns a
1376 * non-zero value, stop the iteration and return that value;
1377 * otherwise, return 0.
1378 */
1379static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1380 each_ref_fn fn, int trim, int flags, void *cb_data)
1381{
1382 struct ref_iterator *iter;
1383
1384 if (!refs)
1385 return 0;
1386
1387 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1388
1389 return do_for_each_ref_iterator(iter, fn, cb_data);
1390}
1391
1392int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1393{
1394 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1395}
1396
1397int for_each_ref(each_ref_fn fn, void *cb_data)
1398{
1399 return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data);
1400}
1401
1402int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1403 each_ref_fn fn, void *cb_data)
1404{
1405 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1406}
1407
1408int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1409{
1410 return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
1411}
1412
1413int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1414{
1415 unsigned int flag = 0;
1416
1417 if (broken)
1418 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1419 return do_for_each_ref(get_main_ref_store(the_repository),
1420 prefix, fn, 0, flag, cb_data);
1421}
1422
1423int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1424 each_ref_fn fn, void *cb_data,
1425 unsigned int broken)
1426{
1427 unsigned int flag = 0;
1428
1429 if (broken)
1430 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1431 return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1432}
1433
1434int for_each_replace_ref(struct repository *r, each_ref_fn fn, void *cb_data)
1435{
1436 return do_for_each_ref(get_main_ref_store(r),
1437 git_replace_ref_base, fn,
1438 strlen(git_replace_ref_base),
1439 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1440}
1441
1442int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1443{
1444 struct strbuf buf = STRBUF_INIT;
1445 int ret;
1446 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1447 ret = do_for_each_ref(get_main_ref_store(the_repository),
1448 buf.buf, fn, 0, 0, cb_data);
1449 strbuf_release(&buf);
1450 return ret;
1451}
1452
1453int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1454{
1455 return do_for_each_ref(refs, "", fn, 0,
1456 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1457}
1458
1459int for_each_rawref(each_ref_fn fn, void *cb_data)
1460{
1461 return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
1462}
1463
1464int refs_read_raw_ref(struct ref_store *ref_store,
1465 const char *refname, struct object_id *oid,
1466 struct strbuf *referent, unsigned int *type)
1467{
1468 return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1469}
1470
1471/* This function needs to return a meaningful errno on failure */
1472const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1473 const char *refname,
1474 int resolve_flags,
1475 struct object_id *oid, int *flags)
1476{
1477 static struct strbuf sb_refname = STRBUF_INIT;
1478 struct object_id unused_oid;
1479 int unused_flags;
1480 int symref_count;
1481
1482 if (!oid)
1483 oid = &unused_oid;
1484 if (!flags)
1485 flags = &unused_flags;
1486
1487 *flags = 0;
1488
1489 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1490 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1491 !refname_is_safe(refname)) {
1492 errno = EINVAL;
1493 return NULL;
1494 }
1495
1496 /*
1497 * dwim_ref() uses REF_ISBROKEN to distinguish between
1498 * missing refs and refs that were present but invalid,
1499 * to complain about the latter to stderr.
1500 *
1501 * We don't know whether the ref exists, so don't set
1502 * REF_ISBROKEN yet.
1503 */
1504 *flags |= REF_BAD_NAME;
1505 }
1506
1507 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1508 unsigned int read_flags = 0;
1509
1510 if (refs_read_raw_ref(refs, refname,
1511 oid, &sb_refname, &read_flags)) {
1512 *flags |= read_flags;
1513
1514 /* In reading mode, refs must eventually resolve */
1515 if (resolve_flags & RESOLVE_REF_READING)
1516 return NULL;
1517
1518 /*
1519 * Otherwise a missing ref is OK. But the files backend
1520 * may show errors besides ENOENT if there are
1521 * similarly-named refs.
1522 */
1523 if (errno != ENOENT &&
1524 errno != EISDIR &&
1525 errno != ENOTDIR)
1526 return NULL;
1527
1528 oidclr(oid);
1529 if (*flags & REF_BAD_NAME)
1530 *flags |= REF_ISBROKEN;
1531 return refname;
1532 }
1533
1534 *flags |= read_flags;
1535
1536 if (!(read_flags & REF_ISSYMREF)) {
1537 if (*flags & REF_BAD_NAME) {
1538 oidclr(oid);
1539 *flags |= REF_ISBROKEN;
1540 }
1541 return refname;
1542 }
1543
1544 refname = sb_refname.buf;
1545 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1546 oidclr(oid);
1547 return refname;
1548 }
1549 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1550 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1551 !refname_is_safe(refname)) {
1552 errno = EINVAL;
1553 return NULL;
1554 }
1555
1556 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1557 }
1558 }
1559
1560 errno = ELOOP;
1561 return NULL;
1562}
1563
1564/* backend functions */
1565int refs_init_db(struct strbuf *err)
1566{
1567 struct ref_store *refs = get_main_ref_store(the_repository);
1568
1569 return refs->be->init_db(refs, err);
1570}
1571
1572const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1573 struct object_id *oid, int *flags)
1574{
1575 return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname,
1576 resolve_flags, oid, flags);
1577}
1578
1579int resolve_gitlink_ref(const char *submodule, const char *refname,
1580 struct object_id *oid)
1581{
1582 struct ref_store *refs;
1583 int flags;
1584
1585 refs = get_submodule_ref_store(submodule);
1586
1587 if (!refs)
1588 return -1;
1589
1590 if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1591 is_null_oid(oid))
1592 return -1;
1593 return 0;
1594}
1595
1596struct ref_store_hash_entry
1597{
1598 struct hashmap_entry ent; /* must be the first member! */
1599
1600 struct ref_store *refs;
1601
1602 /* NUL-terminated identifier of the ref store: */
1603 char name[FLEX_ARRAY];
1604};
1605
1606static int ref_store_hash_cmp(const void *unused_cmp_data,
1607 const void *entry, const void *entry_or_key,
1608 const void *keydata)
1609{
1610 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1611 const char *name = keydata ? keydata : e2->name;
1612
1613 return strcmp(e1->name, name);
1614}
1615
1616static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1617 const char *name, struct ref_store *refs)
1618{
1619 struct ref_store_hash_entry *entry;
1620
1621 FLEX_ALLOC_STR(entry, name, name);
1622 hashmap_entry_init(entry, strhash(name));
1623 entry->refs = refs;
1624 return entry;
1625}
1626
1627/* A hashmap of ref_stores, stored by submodule name: */
1628static struct hashmap submodule_ref_stores;
1629
1630/* A hashmap of ref_stores, stored by worktree id: */
1631static struct hashmap worktree_ref_stores;
1632
1633/*
1634 * Look up a ref store by name. If that ref_store hasn't been
1635 * registered yet, return NULL.
1636 */
1637static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1638 const char *name)
1639{
1640 struct ref_store_hash_entry *entry;
1641
1642 if (!map->tablesize)
1643 /* It's initialized on demand in register_ref_store(). */
1644 return NULL;
1645
1646 entry = hashmap_get_from_hash(map, strhash(name), name);
1647 return entry ? entry->refs : NULL;
1648}
1649
1650/*
1651 * Create, record, and return a ref_store instance for the specified
1652 * gitdir.
1653 */
1654static struct ref_store *ref_store_init(const char *gitdir,
1655 unsigned int flags)
1656{
1657 const char *be_name = "files";
1658 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1659 struct ref_store *refs;
1660
1661 if (!be)
1662 die("BUG: reference backend %s is unknown", be_name);
1663
1664 refs = be->init(gitdir, flags);
1665 return refs;
1666}
1667
1668struct ref_store *get_main_ref_store(struct repository *r)
1669{
1670 if (r->refs)
1671 return r->refs;
1672
1673 r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
1674 return r->refs;
1675}
1676
1677/*
1678 * Associate a ref store with a name. It is a fatal error to call this
1679 * function twice for the same name.
1680 */
1681static void register_ref_store_map(struct hashmap *map,
1682 const char *type,
1683 struct ref_store *refs,
1684 const char *name)
1685{
1686 if (!map->tablesize)
1687 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1688
1689 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1690 die("BUG: %s ref_store '%s' initialized twice", type, name);
1691}
1692
1693struct ref_store *get_submodule_ref_store(const char *submodule)
1694{
1695 struct strbuf submodule_sb = STRBUF_INIT;
1696 struct ref_store *refs;
1697 char *to_free = NULL;
1698 size_t len;
1699
1700 if (!submodule)
1701 return NULL;
1702
1703 len = strlen(submodule);
1704 while (len && is_dir_sep(submodule[len - 1]))
1705 len--;
1706 if (!len)
1707 return NULL;
1708
1709 if (submodule[len])
1710 /* We need to strip off one or more trailing slashes */
1711 submodule = to_free = xmemdupz(submodule, len);
1712
1713 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1714 if (refs)
1715 goto done;
1716
1717 strbuf_addstr(&submodule_sb, submodule);
1718 if (!is_nonbare_repository_dir(&submodule_sb))
1719 goto done;
1720
1721 if (submodule_to_gitdir(&submodule_sb, submodule))
1722 goto done;
1723
1724 /* assume that add_submodule_odb() has been called */
1725 refs = ref_store_init(submodule_sb.buf,
1726 REF_STORE_READ | REF_STORE_ODB);
1727 register_ref_store_map(&submodule_ref_stores, "submodule",
1728 refs, submodule);
1729
1730done:
1731 strbuf_release(&submodule_sb);
1732 free(to_free);
1733
1734 return refs;
1735}
1736
1737struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1738{
1739 struct ref_store *refs;
1740 const char *id;
1741
1742 if (wt->is_current)
1743 return get_main_ref_store(the_repository);
1744
1745 id = wt->id ? wt->id : "/";
1746 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1747 if (refs)
1748 return refs;
1749
1750 if (wt->id)
1751 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1752 REF_STORE_ALL_CAPS);
1753 else
1754 refs = ref_store_init(get_git_common_dir(),
1755 REF_STORE_ALL_CAPS);
1756
1757 if (refs)
1758 register_ref_store_map(&worktree_ref_stores, "worktree",
1759 refs, id);
1760 return refs;
1761}
1762
1763void base_ref_store_init(struct ref_store *refs,
1764 const struct ref_storage_be *be)
1765{
1766 refs->be = be;
1767}
1768
1769/* backend functions */
1770int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1771{
1772 return refs->be->pack_refs(refs, flags);
1773}
1774
1775int refs_peel_ref(struct ref_store *refs, const char *refname,
1776 struct object_id *oid)
1777{
1778 int flag;
1779 struct object_id base;
1780
1781 if (current_ref_iter && current_ref_iter->refname == refname) {
1782 struct object_id peeled;
1783
1784 if (ref_iterator_peel(current_ref_iter, &peeled))
1785 return -1;
1786 oidcpy(oid, &peeled);
1787 return 0;
1788 }
1789
1790 if (refs_read_ref_full(refs, refname,
1791 RESOLVE_REF_READING, &base, &flag))
1792 return -1;
1793
1794 return peel_object(&base, oid);
1795}
1796
1797int peel_ref(const char *refname, struct object_id *oid)
1798{
1799 return refs_peel_ref(get_main_ref_store(the_repository), refname, oid);
1800}
1801
1802int refs_create_symref(struct ref_store *refs,
1803 const char *ref_target,
1804 const char *refs_heads_master,
1805 const char *logmsg)
1806{
1807 return refs->be->create_symref(refs, ref_target,
1808 refs_heads_master,
1809 logmsg);
1810}
1811
1812int create_symref(const char *ref_target, const char *refs_heads_master,
1813 const char *logmsg)
1814{
1815 return refs_create_symref(get_main_ref_store(the_repository), ref_target,
1816 refs_heads_master, logmsg);
1817}
1818
1819int ref_update_reject_duplicates(struct string_list *refnames,
1820 struct strbuf *err)
1821{
1822 size_t i, n = refnames->nr;
1823
1824 assert(err);
1825
1826 for (i = 1; i < n; i++) {
1827 int cmp = strcmp(refnames->items[i - 1].string,
1828 refnames->items[i].string);
1829
1830 if (!cmp) {
1831 strbuf_addf(err,
1832 "multiple updates for ref '%s' not allowed.",
1833 refnames->items[i].string);
1834 return 1;
1835 } else if (cmp > 0) {
1836 die("BUG: ref_update_reject_duplicates() received unsorted list");
1837 }
1838 }
1839 return 0;
1840}
1841
1842int ref_transaction_prepare(struct ref_transaction *transaction,
1843 struct strbuf *err)
1844{
1845 struct ref_store *refs = transaction->ref_store;
1846
1847 switch (transaction->state) {
1848 case REF_TRANSACTION_OPEN:
1849 /* Good. */
1850 break;
1851 case REF_TRANSACTION_PREPARED:
1852 die("BUG: prepare called twice on reference transaction");
1853 break;
1854 case REF_TRANSACTION_CLOSED:
1855 die("BUG: prepare called on a closed reference transaction");
1856 break;
1857 default:
1858 die("BUG: unexpected reference transaction state");
1859 break;
1860 }
1861
1862 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1863 strbuf_addstr(err,
1864 _("ref updates forbidden inside quarantine environment"));
1865 return -1;
1866 }
1867
1868 return refs->be->transaction_prepare(refs, transaction, err);
1869}
1870
1871int ref_transaction_abort(struct ref_transaction *transaction,
1872 struct strbuf *err)
1873{
1874 struct ref_store *refs = transaction->ref_store;
1875 int ret = 0;
1876
1877 switch (transaction->state) {
1878 case REF_TRANSACTION_OPEN:
1879 /* No need to abort explicitly. */
1880 break;
1881 case REF_TRANSACTION_PREPARED:
1882 ret = refs->be->transaction_abort(refs, transaction, err);
1883 break;
1884 case REF_TRANSACTION_CLOSED:
1885 die("BUG: abort called on a closed reference transaction");
1886 break;
1887 default:
1888 die("BUG: unexpected reference transaction state");
1889 break;
1890 }
1891
1892 ref_transaction_free(transaction);
1893 return ret;
1894}
1895
1896int ref_transaction_commit(struct ref_transaction *transaction,
1897 struct strbuf *err)
1898{
1899 struct ref_store *refs = transaction->ref_store;
1900 int ret;
1901
1902 switch (transaction->state) {
1903 case REF_TRANSACTION_OPEN:
1904 /* Need to prepare first. */
1905 ret = ref_transaction_prepare(transaction, err);
1906 if (ret)
1907 return ret;
1908 break;
1909 case REF_TRANSACTION_PREPARED:
1910 /* Fall through to finish. */
1911 break;
1912 case REF_TRANSACTION_CLOSED:
1913 die("BUG: commit called on a closed reference transaction");
1914 break;
1915 default:
1916 die("BUG: unexpected reference transaction state");
1917 break;
1918 }
1919
1920 return refs->be->transaction_finish(refs, transaction, err);
1921}
1922
1923int refs_verify_refname_available(struct ref_store *refs,
1924 const char *refname,
1925 const struct string_list *extras,
1926 const struct string_list *skip,
1927 struct strbuf *err)
1928{
1929 const char *slash;
1930 const char *extra_refname;
1931 struct strbuf dirname = STRBUF_INIT;
1932 struct strbuf referent = STRBUF_INIT;
1933 struct object_id oid;
1934 unsigned int type;
1935 struct ref_iterator *iter;
1936 int ok;
1937 int ret = -1;
1938
1939 /*
1940 * For the sake of comments in this function, suppose that
1941 * refname is "refs/foo/bar".
1942 */
1943
1944 assert(err);
1945
1946 strbuf_grow(&dirname, strlen(refname) + 1);
1947 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1948 /* Expand dirname to the new prefix, not including the trailing slash: */
1949 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1950
1951 /*
1952 * We are still at a leading dir of the refname (e.g.,
1953 * "refs/foo"; if there is a reference with that name,
1954 * it is a conflict, *unless* it is in skip.
1955 */
1956 if (skip && string_list_has_string(skip, dirname.buf))
1957 continue;
1958
1959 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
1960 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1961 dirname.buf, refname);
1962 goto cleanup;
1963 }
1964
1965 if (extras && string_list_has_string(extras, dirname.buf)) {
1966 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1967 refname, dirname.buf);
1968 goto cleanup;
1969 }
1970 }
1971
1972 /*
1973 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1974 * There is no point in searching for a reference with that
1975 * name, because a refname isn't considered to conflict with
1976 * itself. But we still need to check for references whose
1977 * names are in the "refs/foo/bar/" namespace, because they
1978 * *do* conflict.
1979 */
1980 strbuf_addstr(&dirname, refname + dirname.len);
1981 strbuf_addch(&dirname, '/');
1982
1983 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
1984 DO_FOR_EACH_INCLUDE_BROKEN);
1985 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
1986 if (skip &&
1987 string_list_has_string(skip, iter->refname))
1988 continue;
1989
1990 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1991 iter->refname, refname);
1992 ref_iterator_abort(iter);
1993 goto cleanup;
1994 }
1995
1996 if (ok != ITER_DONE)
1997 die("BUG: error while iterating over references");
1998
1999 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
2000 if (extra_refname)
2001 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
2002 refname, extra_refname);
2003 else
2004 ret = 0;
2005
2006cleanup:
2007 strbuf_release(&referent);
2008 strbuf_release(&dirname);
2009 return ret;
2010}
2011
2012int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2013{
2014 struct ref_iterator *iter;
2015
2016 iter = refs->be->reflog_iterator_begin(refs);
2017
2018 return do_for_each_ref_iterator(iter, fn, cb_data);
2019}
2020
2021int for_each_reflog(each_ref_fn fn, void *cb_data)
2022{
2023 return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
2024}
2025
2026int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
2027 const char *refname,
2028 each_reflog_ent_fn fn,
2029 void *cb_data)
2030{
2031 return refs->be->for_each_reflog_ent_reverse(refs, refname,
2032 fn, cb_data);
2033}
2034
2035int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
2036 void *cb_data)
2037{
2038 return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository),
2039 refname, fn, cb_data);
2040}
2041
2042int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
2043 each_reflog_ent_fn fn, void *cb_data)
2044{
2045 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
2046}
2047
2048int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
2049 void *cb_data)
2050{
2051 return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname,
2052 fn, cb_data);
2053}
2054
2055int refs_reflog_exists(struct ref_store *refs, const char *refname)
2056{
2057 return refs->be->reflog_exists(refs, refname);
2058}
2059
2060int reflog_exists(const char *refname)
2061{
2062 return refs_reflog_exists(get_main_ref_store(the_repository), refname);
2063}
2064
2065int refs_create_reflog(struct ref_store *refs, const char *refname,
2066 int force_create, struct strbuf *err)
2067{
2068 return refs->be->create_reflog(refs, refname, force_create, err);
2069}
2070
2071int safe_create_reflog(const char *refname, int force_create,
2072 struct strbuf *err)
2073{
2074 return refs_create_reflog(get_main_ref_store(the_repository), refname,
2075 force_create, err);
2076}
2077
2078int refs_delete_reflog(struct ref_store *refs, const char *refname)
2079{
2080 return refs->be->delete_reflog(refs, refname);
2081}
2082
2083int delete_reflog(const char *refname)
2084{
2085 return refs_delete_reflog(get_main_ref_store(the_repository), refname);
2086}
2087
2088int refs_reflog_expire(struct ref_store *refs,
2089 const char *refname, const struct object_id *oid,
2090 unsigned int flags,
2091 reflog_expiry_prepare_fn prepare_fn,
2092 reflog_expiry_should_prune_fn should_prune_fn,
2093 reflog_expiry_cleanup_fn cleanup_fn,
2094 void *policy_cb_data)
2095{
2096 return refs->be->reflog_expire(refs, refname, oid, flags,
2097 prepare_fn, should_prune_fn,
2098 cleanup_fn, policy_cb_data);
2099}
2100
2101int reflog_expire(const char *refname, const struct object_id *oid,
2102 unsigned int flags,
2103 reflog_expiry_prepare_fn prepare_fn,
2104 reflog_expiry_should_prune_fn should_prune_fn,
2105 reflog_expiry_cleanup_fn cleanup_fn,
2106 void *policy_cb_data)
2107{
2108 return refs_reflog_expire(get_main_ref_store(the_repository),
2109 refname, oid, flags,
2110 prepare_fn, should_prune_fn,
2111 cleanup_fn, policy_cb_data);
2112}
2113
2114int initial_ref_transaction_commit(struct ref_transaction *transaction,
2115 struct strbuf *err)
2116{
2117 struct ref_store *refs = transaction->ref_store;
2118
2119 return refs->be->initial_transaction_commit(refs, transaction, err);
2120}
2121
2122int refs_delete_refs(struct ref_store *refs, const char *msg,
2123 struct string_list *refnames, unsigned int flags)
2124{
2125 return refs->be->delete_refs(refs, msg, refnames, flags);
2126}
2127
2128int delete_refs(const char *msg, struct string_list *refnames,
2129 unsigned int flags)
2130{
2131 return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags);
2132}
2133
2134int refs_rename_ref(struct ref_store *refs, const char *oldref,
2135 const char *newref, const char *logmsg)
2136{
2137 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2138}
2139
2140int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2141{
2142 return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2143}
2144
2145int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2146 const char *newref, const char *logmsg)
2147{
2148 return refs->be->copy_ref(refs, oldref, newref, logmsg);
2149}
2150
2151int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2152{
2153 return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2154}