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-store.h"
13#include "object.h"
14#include "tag.h"
15#include "submodule.h"
16#include "worktree.h"
17#include "argv-array.h"
18#include "repository.h"
19
20/*
21 * List of all available backends
22 */
23static struct ref_storage_be *refs_backends = &refs_be_files;
24
25static struct ref_storage_be *find_ref_storage_backend(const char *name)
26{
27 struct ref_storage_be *be;
28 for (be = refs_backends; be; be = be->next)
29 if (!strcmp(be->name, name))
30 return be;
31 return NULL;
32}
33
34int ref_storage_backend_exists(const char *name)
35{
36 return find_ref_storage_backend(name) != NULL;
37}
38
39/*
40 * How to handle various characters in refnames:
41 * 0: An acceptable character for refs
42 * 1: End-of-component
43 * 2: ., look for a preceding . to reject .. in refs
44 * 3: {, look for a preceding @ to reject @{ in refs
45 * 4: A bad character: ASCII control characters, and
46 * ":", "?", "[", "\", "^", "~", SP, or TAB
47 * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
48 */
49static unsigned char refname_disposition[256] = {
50 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
51 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
52 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
53 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
54 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
55 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
56 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
57 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
58};
59
60/*
61 * Try to read one refname component from the front of refname.
62 * Return the length of the component found, or -1 if the component is
63 * not legal. It is legal if it is something reasonable to have under
64 * ".git/refs/"; We do not like it if:
65 *
66 * - any path component of it begins with ".", or
67 * - it has double dots "..", or
68 * - it has ASCII control characters, or
69 * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
70 * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
71 * - it ends with a "/", or
72 * - it ends with ".lock", or
73 * - it contains a "@{" portion
74 */
75static int check_refname_component(const char *refname, int *flags)
76{
77 const char *cp;
78 char last = '\0';
79
80 for (cp = refname; ; cp++) {
81 int ch = *cp & 255;
82 unsigned char disp = refname_disposition[ch];
83 switch (disp) {
84 case 1:
85 goto out;
86 case 2:
87 if (last == '.')
88 return -1; /* Refname contains "..". */
89 break;
90 case 3:
91 if (last == '@')
92 return -1; /* Refname contains "@{". */
93 break;
94 case 4:
95 return -1;
96 case 5:
97 if (!(*flags & REFNAME_REFSPEC_PATTERN))
98 return -1; /* refspec can't be a pattern */
99
100 /*
101 * Unset the pattern flag so that we only accept
102 * a single asterisk for one side of refspec.
103 */
104 *flags &= ~ REFNAME_REFSPEC_PATTERN;
105 break;
106 }
107 last = ch;
108 }
109out:
110 if (cp == refname)
111 return 0; /* Component has zero length. */
112 if (refname[0] == '.')
113 return -1; /* Component starts with '.'. */
114 if (cp - refname >= LOCK_SUFFIX_LEN &&
115 !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
116 return -1; /* Refname ends with ".lock". */
117 return cp - refname;
118}
119
120int check_refname_format(const char *refname, int flags)
121{
122 int component_len, component_count = 0;
123
124 if (!strcmp(refname, "@"))
125 /* Refname is a single character '@'. */
126 return -1;
127
128 while (1) {
129 /* We are at the start of a path component. */
130 component_len = check_refname_component(refname, &flags);
131 if (component_len <= 0)
132 return -1;
133
134 component_count++;
135 if (refname[component_len] == '\0')
136 break;
137 /* Skip to next component. */
138 refname += component_len + 1;
139 }
140
141 if (refname[component_len - 1] == '.')
142 return -1; /* Refname ends with '.'. */
143 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
144 return -1; /* Refname has only one component. */
145 return 0;
146}
147
148int refname_is_safe(const char *refname)
149{
150 const char *rest;
151
152 if (skip_prefix(refname, "refs/", &rest)) {
153 char *buf;
154 int result;
155 size_t restlen = strlen(rest);
156
157 /* rest must not be empty, or start or end with "/" */
158 if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
159 return 0;
160
161 /*
162 * Does the refname try to escape refs/?
163 * For example: refs/foo/../bar is safe but refs/foo/../../bar
164 * is not.
165 */
166 buf = xmallocz(restlen);
167 result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
168 free(buf);
169 return result;
170 }
171
172 do {
173 if (!isupper(*refname) && *refname != '_')
174 return 0;
175 refname++;
176 } while (*refname);
177 return 1;
178}
179
180/*
181 * Return true if refname, which has the specified oid and flags, can
182 * be resolved to an object in the database. If the referred-to object
183 * does not exist, emit a warning and return false.
184 */
185int ref_resolves_to_object(const char *refname,
186 const struct object_id *oid,
187 unsigned int flags)
188{
189 if (flags & REF_ISBROKEN)
190 return 0;
191 if (!has_sha1_file(oid->hash)) {
192 error(_("%s does not point to a valid object!"), refname);
193 return 0;
194 }
195 return 1;
196}
197
198char *refs_resolve_refdup(struct ref_store *refs,
199 const char *refname, int resolve_flags,
200 struct object_id *oid, int *flags)
201{
202 const char *result;
203
204 result = refs_resolve_ref_unsafe(refs, refname, resolve_flags,
205 oid, flags);
206 return xstrdup_or_null(result);
207}
208
209char *resolve_refdup(const char *refname, int resolve_flags,
210 struct object_id *oid, int *flags)
211{
212 return refs_resolve_refdup(get_main_ref_store(the_repository),
213 refname, resolve_flags,
214 oid, flags);
215}
216
217/* The argument to filter_refs */
218struct ref_filter {
219 const char *pattern;
220 each_ref_fn *fn;
221 void *cb_data;
222};
223
224int refs_read_ref_full(struct ref_store *refs, const char *refname,
225 int resolve_flags, struct object_id *oid, int *flags)
226{
227 if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, oid, flags))
228 return 0;
229 return -1;
230}
231
232int read_ref_full(const char *refname, int resolve_flags, struct object_id *oid, int *flags)
233{
234 return refs_read_ref_full(get_main_ref_store(the_repository), refname,
235 resolve_flags, oid, flags);
236}
237
238int read_ref(const char *refname, struct object_id *oid)
239{
240 return read_ref_full(refname, RESOLVE_REF_READING, oid, NULL);
241}
242
243int ref_exists(const char *refname)
244{
245 return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, NULL, NULL);
246}
247
248static int match_ref_pattern(const char *refname,
249 const struct string_list_item *item)
250{
251 int matched = 0;
252 if (item->util == NULL) {
253 if (!wildmatch(item->string, refname, 0))
254 matched = 1;
255 } else {
256 const char *rest;
257 if (skip_prefix(refname, item->string, &rest) &&
258 (!*rest || *rest == '/'))
259 matched = 1;
260 }
261 return matched;
262}
263
264int ref_filter_match(const char *refname,
265 const struct string_list *include_patterns,
266 const struct string_list *exclude_patterns)
267{
268 struct string_list_item *item;
269
270 if (exclude_patterns && exclude_patterns->nr) {
271 for_each_string_list_item(item, exclude_patterns) {
272 if (match_ref_pattern(refname, item))
273 return 0;
274 }
275 }
276
277 if (include_patterns && include_patterns->nr) {
278 int found = 0;
279 for_each_string_list_item(item, include_patterns) {
280 if (match_ref_pattern(refname, item)) {
281 found = 1;
282 break;
283 }
284 }
285
286 if (!found)
287 return 0;
288 }
289 return 1;
290}
291
292static int filter_refs(const char *refname, const struct object_id *oid,
293 int flags, void *data)
294{
295 struct ref_filter *filter = (struct ref_filter *)data;
296
297 if (wildmatch(filter->pattern, refname, 0))
298 return 0;
299 return filter->fn(refname, oid, flags, filter->cb_data);
300}
301
302enum peel_status peel_object(const struct object_id *name, struct object_id *oid)
303{
304 struct object *o = lookup_unknown_object(name->hash);
305
306 if (o->type == OBJ_NONE) {
307 int type = oid_object_info(the_repository, name, NULL);
308 if (type < 0 || !object_as_type(the_repository, o, type, 0))
309 return PEEL_INVALID;
310 }
311
312 if (o->type != OBJ_TAG)
313 return PEEL_NON_TAG;
314
315 o = deref_tag_noverify(o);
316 if (!o)
317 return PEEL_INVALID;
318
319 oidcpy(oid, &o->oid);
320 return PEEL_PEELED;
321}
322
323struct warn_if_dangling_data {
324 FILE *fp;
325 const char *refname;
326 const struct string_list *refnames;
327 const char *msg_fmt;
328};
329
330static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
331 int flags, void *cb_data)
332{
333 struct warn_if_dangling_data *d = cb_data;
334 const char *resolves_to;
335
336 if (!(flags & REF_ISSYMREF))
337 return 0;
338
339 resolves_to = resolve_ref_unsafe(refname, 0, NULL, NULL);
340 if (!resolves_to
341 || (d->refname
342 ? strcmp(resolves_to, d->refname)
343 : !string_list_has_string(d->refnames, resolves_to))) {
344 return 0;
345 }
346
347 fprintf(d->fp, d->msg_fmt, refname);
348 fputc('\n', d->fp);
349 return 0;
350}
351
352void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
353{
354 struct warn_if_dangling_data data;
355
356 data.fp = fp;
357 data.refname = refname;
358 data.refnames = NULL;
359 data.msg_fmt = msg_fmt;
360 for_each_rawref(warn_if_dangling_symref, &data);
361}
362
363void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
364{
365 struct warn_if_dangling_data data;
366
367 data.fp = fp;
368 data.refname = NULL;
369 data.refnames = refnames;
370 data.msg_fmt = msg_fmt;
371 for_each_rawref(warn_if_dangling_symref, &data);
372}
373
374int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
375{
376 return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
377}
378
379int for_each_tag_ref(each_ref_fn fn, void *cb_data)
380{
381 return refs_for_each_tag_ref(get_main_ref_store(the_repository), fn, cb_data);
382}
383
384int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
385{
386 return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
387}
388
389int for_each_branch_ref(each_ref_fn fn, void *cb_data)
390{
391 return refs_for_each_branch_ref(get_main_ref_store(the_repository), fn, cb_data);
392}
393
394int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
395{
396 return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
397}
398
399int for_each_remote_ref(each_ref_fn fn, void *cb_data)
400{
401 return refs_for_each_remote_ref(get_main_ref_store(the_repository), fn, cb_data);
402}
403
404int head_ref_namespaced(each_ref_fn fn, void *cb_data)
405{
406 struct strbuf buf = STRBUF_INIT;
407 int ret = 0;
408 struct object_id oid;
409 int flag;
410
411 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
412 if (!read_ref_full(buf.buf, RESOLVE_REF_READING, &oid, &flag))
413 ret = fn(buf.buf, &oid, flag, cb_data);
414 strbuf_release(&buf);
415
416 return ret;
417}
418
419void normalize_glob_ref(struct string_list_item *item, const char *prefix,
420 const char *pattern)
421{
422 struct strbuf normalized_pattern = STRBUF_INIT;
423
424 if (*pattern == '/')
425 BUG("pattern must not start with '/'");
426
427 if (prefix) {
428 strbuf_addstr(&normalized_pattern, prefix);
429 }
430 else if (!starts_with(pattern, "refs/"))
431 strbuf_addstr(&normalized_pattern, "refs/");
432 strbuf_addstr(&normalized_pattern, pattern);
433 strbuf_strip_suffix(&normalized_pattern, "/");
434
435 item->string = strbuf_detach(&normalized_pattern, NULL);
436 item->util = has_glob_specials(pattern) ? NULL : item->string;
437 strbuf_release(&normalized_pattern);
438}
439
440int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
441 const char *prefix, void *cb_data)
442{
443 struct strbuf real_pattern = STRBUF_INIT;
444 struct ref_filter filter;
445 int ret;
446
447 if (!prefix && !starts_with(pattern, "refs/"))
448 strbuf_addstr(&real_pattern, "refs/");
449 else if (prefix)
450 strbuf_addstr(&real_pattern, prefix);
451 strbuf_addstr(&real_pattern, pattern);
452
453 if (!has_glob_specials(pattern)) {
454 /* Append implied '/' '*' if not present. */
455 strbuf_complete(&real_pattern, '/');
456 /* No need to check for '*', there is none. */
457 strbuf_addch(&real_pattern, '*');
458 }
459
460 filter.pattern = real_pattern.buf;
461 filter.fn = fn;
462 filter.cb_data = cb_data;
463 ret = for_each_ref(filter_refs, &filter);
464
465 strbuf_release(&real_pattern);
466 return ret;
467}
468
469int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
470{
471 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
472}
473
474const char *prettify_refname(const char *name)
475{
476 if (skip_prefix(name, "refs/heads/", &name) ||
477 skip_prefix(name, "refs/tags/", &name) ||
478 skip_prefix(name, "refs/remotes/", &name))
479 ; /* nothing */
480 return name;
481}
482
483static const char *ref_rev_parse_rules[] = {
484 "%.*s",
485 "refs/%.*s",
486 "refs/tags/%.*s",
487 "refs/heads/%.*s",
488 "refs/remotes/%.*s",
489 "refs/remotes/%.*s/HEAD",
490 NULL
491};
492
493#define NUM_REV_PARSE_RULES (ARRAY_SIZE(ref_rev_parse_rules) - 1)
494
495/*
496 * Is it possible that the caller meant full_name with abbrev_name?
497 * If so return a non-zero value to signal "yes"; the magnitude of
498 * the returned value gives the precedence used for disambiguation.
499 *
500 * If abbrev_name cannot mean full_name, return 0.
501 */
502int refname_match(const char *abbrev_name, const char *full_name)
503{
504 const char **p;
505 const int abbrev_name_len = strlen(abbrev_name);
506 const int num_rules = NUM_REV_PARSE_RULES;
507
508 for (p = ref_rev_parse_rules; *p; p++)
509 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name)))
510 return &ref_rev_parse_rules[num_rules] - p;
511
512 return 0;
513}
514
515/*
516 * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add
517 * the results to 'prefixes'
518 */
519void expand_ref_prefix(struct argv_array *prefixes, const char *prefix)
520{
521 const char **p;
522 int len = strlen(prefix);
523
524 for (p = ref_rev_parse_rules; *p; p++)
525 argv_array_pushf(prefixes, *p, len, prefix);
526}
527
528/*
529 * *string and *len will only be substituted, and *string returned (for
530 * later free()ing) if the string passed in is a magic short-hand form
531 * to name a branch.
532 */
533static char *substitute_branch_name(const char **string, int *len)
534{
535 struct strbuf buf = STRBUF_INIT;
536 int ret = interpret_branch_name(*string, *len, &buf, 0);
537
538 if (ret == *len) {
539 size_t size;
540 *string = strbuf_detach(&buf, &size);
541 *len = size;
542 return (char *)*string;
543 }
544
545 return NULL;
546}
547
548int dwim_ref(const char *str, int len, struct object_id *oid, char **ref)
549{
550 char *last_branch = substitute_branch_name(&str, &len);
551 int refs_found = expand_ref(str, len, oid, ref);
552 free(last_branch);
553 return refs_found;
554}
555
556int expand_ref(const char *str, int len, struct object_id *oid, char **ref)
557{
558 const char **p, *r;
559 int refs_found = 0;
560 struct strbuf fullref = STRBUF_INIT;
561
562 *ref = NULL;
563 for (p = ref_rev_parse_rules; *p; p++) {
564 struct object_id oid_from_ref;
565 struct object_id *this_result;
566 int flag;
567
568 this_result = refs_found ? &oid_from_ref : oid;
569 strbuf_reset(&fullref);
570 strbuf_addf(&fullref, *p, len, str);
571 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
572 this_result, &flag);
573 if (r) {
574 if (!refs_found++)
575 *ref = xstrdup(r);
576 if (!warn_ambiguous_refs)
577 break;
578 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
579 warning(_("ignoring dangling symref %s"), fullref.buf);
580 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
581 warning(_("ignoring broken ref %s"), fullref.buf);
582 }
583 }
584 strbuf_release(&fullref);
585 return refs_found;
586}
587
588int dwim_log(const char *str, int len, struct object_id *oid, char **log)
589{
590 char *last_branch = substitute_branch_name(&str, &len);
591 const char **p;
592 int logs_found = 0;
593 struct strbuf path = STRBUF_INIT;
594
595 *log = NULL;
596 for (p = ref_rev_parse_rules; *p; p++) {
597 struct object_id hash;
598 const char *ref, *it;
599
600 strbuf_reset(&path);
601 strbuf_addf(&path, *p, len, str);
602 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
603 &hash, NULL);
604 if (!ref)
605 continue;
606 if (reflog_exists(path.buf))
607 it = path.buf;
608 else if (strcmp(ref, path.buf) && reflog_exists(ref))
609 it = ref;
610 else
611 continue;
612 if (!logs_found++) {
613 *log = xstrdup(it);
614 oidcpy(oid, &hash);
615 }
616 if (!warn_ambiguous_refs)
617 break;
618 }
619 strbuf_release(&path);
620 free(last_branch);
621 return logs_found;
622}
623
624static int is_per_worktree_ref(const char *refname)
625{
626 return !strcmp(refname, "HEAD") ||
627 starts_with(refname, "refs/worktree/") ||
628 starts_with(refname, "refs/bisect/") ||
629 starts_with(refname, "refs/rewritten/");
630}
631
632static int is_pseudoref_syntax(const char *refname)
633{
634 const char *c;
635
636 for (c = refname; *c; c++) {
637 if (!isupper(*c) && *c != '-' && *c != '_')
638 return 0;
639 }
640
641 return 1;
642}
643
644enum ref_type ref_type(const char *refname)
645{
646 if (is_per_worktree_ref(refname))
647 return REF_TYPE_PER_WORKTREE;
648 if (is_pseudoref_syntax(refname))
649 return REF_TYPE_PSEUDOREF;
650 return REF_TYPE_NORMAL;
651}
652
653long get_files_ref_lock_timeout_ms(void)
654{
655 static int configured = 0;
656
657 /* The default timeout is 100 ms: */
658 static int timeout_ms = 100;
659
660 if (!configured) {
661 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
662 configured = 1;
663 }
664
665 return timeout_ms;
666}
667
668static int write_pseudoref(const char *pseudoref, const struct object_id *oid,
669 const struct object_id *old_oid, struct strbuf *err)
670{
671 const char *filename;
672 int fd;
673 struct lock_file lock = LOCK_INIT;
674 struct strbuf buf = STRBUF_INIT;
675 int ret = -1;
676
677 if (!oid)
678 return 0;
679
680 strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
681
682 filename = git_path("%s", pseudoref);
683 fd = hold_lock_file_for_update_timeout(&lock, filename, 0,
684 get_files_ref_lock_timeout_ms());
685 if (fd < 0) {
686 strbuf_addf(err, _("could not open '%s' for writing: %s"),
687 filename, strerror(errno));
688 goto done;
689 }
690
691 if (old_oid) {
692 struct object_id actual_old_oid;
693
694 if (read_ref(pseudoref, &actual_old_oid)) {
695 if (!is_null_oid(old_oid)) {
696 strbuf_addf(err, _("could not read ref '%s'"),
697 pseudoref);
698 rollback_lock_file(&lock);
699 goto done;
700 }
701 } else if (is_null_oid(old_oid)) {
702 strbuf_addf(err, _("ref '%s' already exists"),
703 pseudoref);
704 rollback_lock_file(&lock);
705 goto done;
706 } else if (!oideq(&actual_old_oid, old_oid)) {
707 strbuf_addf(err, _("unexpected object ID when writing '%s'"),
708 pseudoref);
709 rollback_lock_file(&lock);
710 goto done;
711 }
712 }
713
714 if (write_in_full(fd, buf.buf, buf.len) < 0) {
715 strbuf_addf(err, _("could not write to '%s'"), filename);
716 rollback_lock_file(&lock);
717 goto done;
718 }
719
720 commit_lock_file(&lock);
721 ret = 0;
722done:
723 strbuf_release(&buf);
724 return ret;
725}
726
727static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
728{
729 const char *filename;
730
731 filename = git_path("%s", pseudoref);
732
733 if (old_oid && !is_null_oid(old_oid)) {
734 struct lock_file lock = LOCK_INIT;
735 int fd;
736 struct object_id actual_old_oid;
737
738 fd = hold_lock_file_for_update_timeout(
739 &lock, filename, 0,
740 get_files_ref_lock_timeout_ms());
741 if (fd < 0) {
742 error_errno(_("could not open '%s' for writing"),
743 filename);
744 return -1;
745 }
746 if (read_ref(pseudoref, &actual_old_oid))
747 die(_("could not read ref '%s'"), pseudoref);
748 if (!oideq(&actual_old_oid, old_oid)) {
749 error(_("unexpected object ID when deleting '%s'"),
750 pseudoref);
751 rollback_lock_file(&lock);
752 return -1;
753 }
754
755 unlink(filename);
756 rollback_lock_file(&lock);
757 } else {
758 unlink(filename);
759 }
760
761 return 0;
762}
763
764int refs_delete_ref(struct ref_store *refs, const char *msg,
765 const char *refname,
766 const struct object_id *old_oid,
767 unsigned int flags)
768{
769 struct ref_transaction *transaction;
770 struct strbuf err = STRBUF_INIT;
771
772 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
773 assert(refs == get_main_ref_store(the_repository));
774 return delete_pseudoref(refname, old_oid);
775 }
776
777 transaction = ref_store_transaction_begin(refs, &err);
778 if (!transaction ||
779 ref_transaction_delete(transaction, refname, old_oid,
780 flags, msg, &err) ||
781 ref_transaction_commit(transaction, &err)) {
782 error("%s", err.buf);
783 ref_transaction_free(transaction);
784 strbuf_release(&err);
785 return 1;
786 }
787 ref_transaction_free(transaction);
788 strbuf_release(&err);
789 return 0;
790}
791
792int delete_ref(const char *msg, const char *refname,
793 const struct object_id *old_oid, unsigned int flags)
794{
795 return refs_delete_ref(get_main_ref_store(the_repository), msg, refname,
796 old_oid, flags);
797}
798
799void copy_reflog_msg(struct strbuf *sb, const char *msg)
800{
801 char c;
802 int wasspace = 1;
803
804 strbuf_addch(sb, '\t');
805 while ((c = *msg++)) {
806 if (wasspace && isspace(c))
807 continue;
808 wasspace = isspace(c);
809 if (wasspace)
810 c = ' ';
811 strbuf_addch(sb, c);
812 }
813 strbuf_rtrim(sb);
814}
815
816int should_autocreate_reflog(const char *refname)
817{
818 switch (log_all_ref_updates) {
819 case LOG_REFS_ALWAYS:
820 return 1;
821 case LOG_REFS_NORMAL:
822 return starts_with(refname, "refs/heads/") ||
823 starts_with(refname, "refs/remotes/") ||
824 starts_with(refname, "refs/notes/") ||
825 !strcmp(refname, "HEAD");
826 default:
827 return 0;
828 }
829}
830
831int is_branch(const char *refname)
832{
833 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
834}
835
836struct read_ref_at_cb {
837 const char *refname;
838 timestamp_t at_time;
839 int cnt;
840 int reccnt;
841 struct object_id *oid;
842 int found_it;
843
844 struct object_id ooid;
845 struct object_id noid;
846 int tz;
847 timestamp_t date;
848 char **msg;
849 timestamp_t *cutoff_time;
850 int *cutoff_tz;
851 int *cutoff_cnt;
852};
853
854static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
855 const char *email, timestamp_t timestamp, int tz,
856 const char *message, void *cb_data)
857{
858 struct read_ref_at_cb *cb = cb_data;
859
860 cb->reccnt++;
861 cb->tz = tz;
862 cb->date = timestamp;
863
864 if (timestamp <= cb->at_time || cb->cnt == 0) {
865 if (cb->msg)
866 *cb->msg = xstrdup(message);
867 if (cb->cutoff_time)
868 *cb->cutoff_time = timestamp;
869 if (cb->cutoff_tz)
870 *cb->cutoff_tz = tz;
871 if (cb->cutoff_cnt)
872 *cb->cutoff_cnt = cb->reccnt - 1;
873 /*
874 * we have not yet updated cb->[n|o]oid so they still
875 * hold the values for the previous record.
876 */
877 if (!is_null_oid(&cb->ooid)) {
878 oidcpy(cb->oid, noid);
879 if (!oideq(&cb->ooid, noid))
880 warning(_("log for ref %s has gap after %s"),
881 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
882 }
883 else if (cb->date == cb->at_time)
884 oidcpy(cb->oid, noid);
885 else if (!oideq(noid, cb->oid))
886 warning(_("log for ref %s unexpectedly ended on %s"),
887 cb->refname, show_date(cb->date, cb->tz,
888 DATE_MODE(RFC2822)));
889 oidcpy(&cb->ooid, ooid);
890 oidcpy(&cb->noid, noid);
891 cb->found_it = 1;
892 return 1;
893 }
894 oidcpy(&cb->ooid, ooid);
895 oidcpy(&cb->noid, noid);
896 if (cb->cnt > 0)
897 cb->cnt--;
898 return 0;
899}
900
901static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
902 const char *email, timestamp_t timestamp,
903 int tz, const char *message, void *cb_data)
904{
905 struct read_ref_at_cb *cb = cb_data;
906
907 if (cb->msg)
908 *cb->msg = xstrdup(message);
909 if (cb->cutoff_time)
910 *cb->cutoff_time = timestamp;
911 if (cb->cutoff_tz)
912 *cb->cutoff_tz = tz;
913 if (cb->cutoff_cnt)
914 *cb->cutoff_cnt = cb->reccnt;
915 oidcpy(cb->oid, ooid);
916 if (is_null_oid(cb->oid))
917 oidcpy(cb->oid, noid);
918 /* We just want the first entry */
919 return 1;
920}
921
922int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
923 struct object_id *oid, char **msg,
924 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
925{
926 struct read_ref_at_cb cb;
927
928 memset(&cb, 0, sizeof(cb));
929 cb.refname = refname;
930 cb.at_time = at_time;
931 cb.cnt = cnt;
932 cb.msg = msg;
933 cb.cutoff_time = cutoff_time;
934 cb.cutoff_tz = cutoff_tz;
935 cb.cutoff_cnt = cutoff_cnt;
936 cb.oid = oid;
937
938 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
939
940 if (!cb.reccnt) {
941 if (flags & GET_OID_QUIETLY)
942 exit(128);
943 else
944 die(_("log for %s is empty"), refname);
945 }
946 if (cb.found_it)
947 return 0;
948
949 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
950
951 return 1;
952}
953
954struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
955 struct strbuf *err)
956{
957 struct ref_transaction *tr;
958 assert(err);
959
960 tr = xcalloc(1, sizeof(struct ref_transaction));
961 tr->ref_store = refs;
962 return tr;
963}
964
965struct ref_transaction *ref_transaction_begin(struct strbuf *err)
966{
967 return ref_store_transaction_begin(get_main_ref_store(the_repository), err);
968}
969
970void ref_transaction_free(struct ref_transaction *transaction)
971{
972 size_t i;
973
974 if (!transaction)
975 return;
976
977 switch (transaction->state) {
978 case REF_TRANSACTION_OPEN:
979 case REF_TRANSACTION_CLOSED:
980 /* OK */
981 break;
982 case REF_TRANSACTION_PREPARED:
983 BUG("free called on a prepared reference transaction");
984 break;
985 default:
986 BUG("unexpected reference transaction state");
987 break;
988 }
989
990 for (i = 0; i < transaction->nr; i++) {
991 free(transaction->updates[i]->msg);
992 free(transaction->updates[i]);
993 }
994 free(transaction->updates);
995 free(transaction);
996}
997
998struct ref_update *ref_transaction_add_update(
999 struct ref_transaction *transaction,
1000 const char *refname, unsigned int flags,
1001 const struct object_id *new_oid,
1002 const struct object_id *old_oid,
1003 const char *msg)
1004{
1005 struct ref_update *update;
1006
1007 if (transaction->state != REF_TRANSACTION_OPEN)
1008 BUG("update called for transaction that is not open");
1009
1010 FLEX_ALLOC_STR(update, refname, refname);
1011 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
1012 transaction->updates[transaction->nr++] = update;
1013
1014 update->flags = flags;
1015
1016 if (flags & REF_HAVE_NEW)
1017 oidcpy(&update->new_oid, new_oid);
1018 if (flags & REF_HAVE_OLD)
1019 oidcpy(&update->old_oid, old_oid);
1020 update->msg = xstrdup_or_null(msg);
1021 return update;
1022}
1023
1024int ref_transaction_update(struct ref_transaction *transaction,
1025 const char *refname,
1026 const struct object_id *new_oid,
1027 const struct object_id *old_oid,
1028 unsigned int flags, const char *msg,
1029 struct strbuf *err)
1030{
1031 assert(err);
1032
1033 if ((new_oid && !is_null_oid(new_oid)) ?
1034 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
1035 !refname_is_safe(refname)) {
1036 strbuf_addf(err, _("refusing to update ref with bad name '%s'"),
1037 refname);
1038 return -1;
1039 }
1040
1041 if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
1042 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
1043
1044 flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
1045
1046 ref_transaction_add_update(transaction, refname, flags,
1047 new_oid, old_oid, msg);
1048 return 0;
1049}
1050
1051int ref_transaction_create(struct ref_transaction *transaction,
1052 const char *refname,
1053 const struct object_id *new_oid,
1054 unsigned int flags, const char *msg,
1055 struct strbuf *err)
1056{
1057 if (!new_oid || is_null_oid(new_oid))
1058 BUG("create called without valid new_oid");
1059 return ref_transaction_update(transaction, refname, new_oid,
1060 &null_oid, flags, msg, err);
1061}
1062
1063int ref_transaction_delete(struct ref_transaction *transaction,
1064 const char *refname,
1065 const struct object_id *old_oid,
1066 unsigned int flags, const char *msg,
1067 struct strbuf *err)
1068{
1069 if (old_oid && is_null_oid(old_oid))
1070 BUG("delete called with old_oid set to zeros");
1071 return ref_transaction_update(transaction, refname,
1072 &null_oid, old_oid,
1073 flags, msg, err);
1074}
1075
1076int ref_transaction_verify(struct ref_transaction *transaction,
1077 const char *refname,
1078 const struct object_id *old_oid,
1079 unsigned int flags,
1080 struct strbuf *err)
1081{
1082 if (!old_oid)
1083 BUG("verify called with old_oid set to NULL");
1084 return ref_transaction_update(transaction, refname,
1085 NULL, old_oid,
1086 flags, NULL, err);
1087}
1088
1089int refs_update_ref(struct ref_store *refs, const char *msg,
1090 const char *refname, const struct object_id *new_oid,
1091 const struct object_id *old_oid, unsigned int flags,
1092 enum action_on_err onerr)
1093{
1094 struct ref_transaction *t = NULL;
1095 struct strbuf err = STRBUF_INIT;
1096 int ret = 0;
1097
1098 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1099 assert(refs == get_main_ref_store(the_repository));
1100 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1101 } else {
1102 t = ref_store_transaction_begin(refs, &err);
1103 if (!t ||
1104 ref_transaction_update(t, refname, new_oid, old_oid,
1105 flags, msg, &err) ||
1106 ref_transaction_commit(t, &err)) {
1107 ret = 1;
1108 ref_transaction_free(t);
1109 }
1110 }
1111 if (ret) {
1112 const char *str = _("update_ref failed for ref '%s': %s");
1113
1114 switch (onerr) {
1115 case UPDATE_REFS_MSG_ON_ERR:
1116 error(str, refname, err.buf);
1117 break;
1118 case UPDATE_REFS_DIE_ON_ERR:
1119 die(str, refname, err.buf);
1120 break;
1121 case UPDATE_REFS_QUIET_ON_ERR:
1122 break;
1123 }
1124 strbuf_release(&err);
1125 return 1;
1126 }
1127 strbuf_release(&err);
1128 if (t)
1129 ref_transaction_free(t);
1130 return 0;
1131}
1132
1133int update_ref(const char *msg, const char *refname,
1134 const struct object_id *new_oid,
1135 const struct object_id *old_oid,
1136 unsigned int flags, enum action_on_err onerr)
1137{
1138 return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid,
1139 old_oid, flags, onerr);
1140}
1141
1142char *shorten_unambiguous_ref(const char *refname, int strict)
1143{
1144 int i;
1145 static char **scanf_fmts;
1146 static int nr_rules;
1147 char *short_name;
1148 struct strbuf resolved_buf = STRBUF_INIT;
1149
1150 if (!nr_rules) {
1151 /*
1152 * Pre-generate scanf formats from ref_rev_parse_rules[].
1153 * Generate a format suitable for scanf from a
1154 * ref_rev_parse_rules rule by interpolating "%s" at the
1155 * location of the "%.*s".
1156 */
1157 size_t total_len = 0;
1158 size_t offset = 0;
1159
1160 /* the rule list is NULL terminated, count them first */
1161 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1162 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1163 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1164
1165 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1166
1167 offset = 0;
1168 for (i = 0; i < nr_rules; i++) {
1169 assert(offset < total_len);
1170 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1171 offset += xsnprintf(scanf_fmts[i], total_len - offset,
1172 ref_rev_parse_rules[i], 2, "%s") + 1;
1173 }
1174 }
1175
1176 /* bail out if there are no rules */
1177 if (!nr_rules)
1178 return xstrdup(refname);
1179
1180 /* buffer for scanf result, at most refname must fit */
1181 short_name = xstrdup(refname);
1182
1183 /* skip first rule, it will always match */
1184 for (i = nr_rules - 1; i > 0 ; --i) {
1185 int j;
1186 int rules_to_fail = i;
1187 int short_name_len;
1188
1189 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1190 continue;
1191
1192 short_name_len = strlen(short_name);
1193
1194 /*
1195 * in strict mode, all (except the matched one) rules
1196 * must fail to resolve to a valid non-ambiguous ref
1197 */
1198 if (strict)
1199 rules_to_fail = nr_rules;
1200
1201 /*
1202 * check if the short name resolves to a valid ref,
1203 * but use only rules prior to the matched one
1204 */
1205 for (j = 0; j < rules_to_fail; j++) {
1206 const char *rule = ref_rev_parse_rules[j];
1207
1208 /* skip matched rule */
1209 if (i == j)
1210 continue;
1211
1212 /*
1213 * the short name is ambiguous, if it resolves
1214 * (with this previous rule) to a valid ref
1215 * read_ref() returns 0 on success
1216 */
1217 strbuf_reset(&resolved_buf);
1218 strbuf_addf(&resolved_buf, rule,
1219 short_name_len, short_name);
1220 if (ref_exists(resolved_buf.buf))
1221 break;
1222 }
1223
1224 /*
1225 * short name is non-ambiguous if all previous rules
1226 * haven't resolved to a valid ref
1227 */
1228 if (j == rules_to_fail) {
1229 strbuf_release(&resolved_buf);
1230 return short_name;
1231 }
1232 }
1233
1234 strbuf_release(&resolved_buf);
1235 free(short_name);
1236 return xstrdup(refname);
1237}
1238
1239static struct string_list *hide_refs;
1240
1241int parse_hide_refs_config(const char *var, const char *value, const char *section)
1242{
1243 const char *key;
1244 if (!strcmp("transfer.hiderefs", var) ||
1245 (!parse_config_key(var, section, NULL, NULL, &key) &&
1246 !strcmp(key, "hiderefs"))) {
1247 char *ref;
1248 int len;
1249
1250 if (!value)
1251 return config_error_nonbool(var);
1252 ref = xstrdup(value);
1253 len = strlen(ref);
1254 while (len && ref[len - 1] == '/')
1255 ref[--len] = '\0';
1256 if (!hide_refs) {
1257 hide_refs = xcalloc(1, sizeof(*hide_refs));
1258 hide_refs->strdup_strings = 1;
1259 }
1260 string_list_append(hide_refs, ref);
1261 }
1262 return 0;
1263}
1264
1265int ref_is_hidden(const char *refname, const char *refname_full)
1266{
1267 int i;
1268
1269 if (!hide_refs)
1270 return 0;
1271 for (i = hide_refs->nr - 1; i >= 0; i--) {
1272 const char *match = hide_refs->items[i].string;
1273 const char *subject;
1274 int neg = 0;
1275 const char *p;
1276
1277 if (*match == '!') {
1278 neg = 1;
1279 match++;
1280 }
1281
1282 if (*match == '^') {
1283 subject = refname_full;
1284 match++;
1285 } else {
1286 subject = refname;
1287 }
1288
1289 /* refname can be NULL when namespaces are used. */
1290 if (subject &&
1291 skip_prefix(subject, match, &p) &&
1292 (!*p || *p == '/'))
1293 return !neg;
1294 }
1295 return 0;
1296}
1297
1298const char *find_descendant_ref(const char *dirname,
1299 const struct string_list *extras,
1300 const struct string_list *skip)
1301{
1302 int pos;
1303
1304 if (!extras)
1305 return NULL;
1306
1307 /*
1308 * Look at the place where dirname would be inserted into
1309 * extras. If there is an entry at that position that starts
1310 * with dirname (remember, dirname includes the trailing
1311 * slash) and is not in skip, then we have a conflict.
1312 */
1313 for (pos = string_list_find_insert_index(extras, dirname, 0);
1314 pos < extras->nr; pos++) {
1315 const char *extra_refname = extras->items[pos].string;
1316
1317 if (!starts_with(extra_refname, dirname))
1318 break;
1319
1320 if (!skip || !string_list_has_string(skip, extra_refname))
1321 return extra_refname;
1322 }
1323 return NULL;
1324}
1325
1326int refs_rename_ref_available(struct ref_store *refs,
1327 const char *old_refname,
1328 const char *new_refname)
1329{
1330 struct string_list skip = STRING_LIST_INIT_NODUP;
1331 struct strbuf err = STRBUF_INIT;
1332 int ok;
1333
1334 string_list_insert(&skip, old_refname);
1335 ok = !refs_verify_refname_available(refs, new_refname,
1336 NULL, &skip, &err);
1337 if (!ok)
1338 error("%s", err.buf);
1339
1340 string_list_clear(&skip, 0);
1341 strbuf_release(&err);
1342 return ok;
1343}
1344
1345int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1346{
1347 struct object_id oid;
1348 int flag;
1349
1350 if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1351 &oid, &flag))
1352 return fn("HEAD", &oid, flag, cb_data);
1353
1354 return 0;
1355}
1356
1357int head_ref(each_ref_fn fn, void *cb_data)
1358{
1359 return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data);
1360}
1361
1362struct ref_iterator *refs_ref_iterator_begin(
1363 struct ref_store *refs,
1364 const char *prefix, int trim, int flags)
1365{
1366 struct ref_iterator *iter;
1367
1368 if (ref_paranoia < 0)
1369 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1370 if (ref_paranoia)
1371 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1372
1373 iter = refs->be->iterator_begin(refs, prefix, flags);
1374
1375 /*
1376 * `iterator_begin()` already takes care of prefix, but we
1377 * might need to do some trimming:
1378 */
1379 if (trim)
1380 iter = prefix_ref_iterator_begin(iter, "", trim);
1381
1382 /* Sanity check for subclasses: */
1383 if (!iter->ordered)
1384 BUG("reference iterator is not ordered");
1385
1386 return iter;
1387}
1388
1389/*
1390 * Call fn for each reference in the specified submodule for which the
1391 * refname begins with prefix. If trim is non-zero, then trim that
1392 * many characters off the beginning of each refname before passing
1393 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1394 * include broken references in the iteration. If fn ever returns a
1395 * non-zero value, stop the iteration and return that value;
1396 * otherwise, return 0.
1397 */
1398static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1399 each_ref_fn fn, int trim, int flags, void *cb_data)
1400{
1401 struct ref_iterator *iter;
1402
1403 if (!refs)
1404 return 0;
1405
1406 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1407
1408 return do_for_each_ref_iterator(iter, fn, cb_data);
1409}
1410
1411int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1412{
1413 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1414}
1415
1416int for_each_ref(each_ref_fn fn, void *cb_data)
1417{
1418 return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data);
1419}
1420
1421int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1422 each_ref_fn fn, void *cb_data)
1423{
1424 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1425}
1426
1427int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1428{
1429 return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
1430}
1431
1432int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1433{
1434 unsigned int flag = 0;
1435
1436 if (broken)
1437 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1438 return do_for_each_ref(get_main_ref_store(the_repository),
1439 prefix, fn, 0, flag, cb_data);
1440}
1441
1442int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1443 each_ref_fn fn, void *cb_data,
1444 unsigned int broken)
1445{
1446 unsigned int flag = 0;
1447
1448 if (broken)
1449 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1450 return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1451}
1452
1453int for_each_replace_ref(struct repository *r, each_ref_fn fn, void *cb_data)
1454{
1455 return do_for_each_ref(get_main_ref_store(r),
1456 git_replace_ref_base, fn,
1457 strlen(git_replace_ref_base),
1458 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1459}
1460
1461int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1462{
1463 struct strbuf buf = STRBUF_INIT;
1464 int ret;
1465 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1466 ret = do_for_each_ref(get_main_ref_store(the_repository),
1467 buf.buf, fn, 0, 0, cb_data);
1468 strbuf_release(&buf);
1469 return ret;
1470}
1471
1472int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1473{
1474 return do_for_each_ref(refs, "", fn, 0,
1475 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1476}
1477
1478int for_each_rawref(each_ref_fn fn, void *cb_data)
1479{
1480 return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
1481}
1482
1483int refs_read_raw_ref(struct ref_store *ref_store,
1484 const char *refname, struct object_id *oid,
1485 struct strbuf *referent, unsigned int *type)
1486{
1487 return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1488}
1489
1490/* This function needs to return a meaningful errno on failure */
1491const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1492 const char *refname,
1493 int resolve_flags,
1494 struct object_id *oid, int *flags)
1495{
1496 static struct strbuf sb_refname = STRBUF_INIT;
1497 struct object_id unused_oid;
1498 int unused_flags;
1499 int symref_count;
1500
1501 if (!oid)
1502 oid = &unused_oid;
1503 if (!flags)
1504 flags = &unused_flags;
1505
1506 *flags = 0;
1507
1508 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1509 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1510 !refname_is_safe(refname)) {
1511 errno = EINVAL;
1512 return NULL;
1513 }
1514
1515 /*
1516 * dwim_ref() uses REF_ISBROKEN to distinguish between
1517 * missing refs and refs that were present but invalid,
1518 * to complain about the latter to stderr.
1519 *
1520 * We don't know whether the ref exists, so don't set
1521 * REF_ISBROKEN yet.
1522 */
1523 *flags |= REF_BAD_NAME;
1524 }
1525
1526 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1527 unsigned int read_flags = 0;
1528
1529 if (refs_read_raw_ref(refs, refname,
1530 oid, &sb_refname, &read_flags)) {
1531 *flags |= read_flags;
1532
1533 /* In reading mode, refs must eventually resolve */
1534 if (resolve_flags & RESOLVE_REF_READING)
1535 return NULL;
1536
1537 /*
1538 * Otherwise a missing ref is OK. But the files backend
1539 * may show errors besides ENOENT if there are
1540 * similarly-named refs.
1541 */
1542 if (errno != ENOENT &&
1543 errno != EISDIR &&
1544 errno != ENOTDIR)
1545 return NULL;
1546
1547 oidclr(oid);
1548 if (*flags & REF_BAD_NAME)
1549 *flags |= REF_ISBROKEN;
1550 return refname;
1551 }
1552
1553 *flags |= read_flags;
1554
1555 if (!(read_flags & REF_ISSYMREF)) {
1556 if (*flags & REF_BAD_NAME) {
1557 oidclr(oid);
1558 *flags |= REF_ISBROKEN;
1559 }
1560 return refname;
1561 }
1562
1563 refname = sb_refname.buf;
1564 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1565 oidclr(oid);
1566 return refname;
1567 }
1568 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1569 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1570 !refname_is_safe(refname)) {
1571 errno = EINVAL;
1572 return NULL;
1573 }
1574
1575 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1576 }
1577 }
1578
1579 errno = ELOOP;
1580 return NULL;
1581}
1582
1583/* backend functions */
1584int refs_init_db(struct strbuf *err)
1585{
1586 struct ref_store *refs = get_main_ref_store(the_repository);
1587
1588 return refs->be->init_db(refs, err);
1589}
1590
1591const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1592 struct object_id *oid, int *flags)
1593{
1594 return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname,
1595 resolve_flags, oid, flags);
1596}
1597
1598int resolve_gitlink_ref(const char *submodule, const char *refname,
1599 struct object_id *oid)
1600{
1601 struct ref_store *refs;
1602 int flags;
1603
1604 refs = get_submodule_ref_store(submodule);
1605
1606 if (!refs)
1607 return -1;
1608
1609 if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1610 is_null_oid(oid))
1611 return -1;
1612 return 0;
1613}
1614
1615struct ref_store_hash_entry
1616{
1617 struct hashmap_entry ent; /* must be the first member! */
1618
1619 struct ref_store *refs;
1620
1621 /* NUL-terminated identifier of the ref store: */
1622 char name[FLEX_ARRAY];
1623};
1624
1625static int ref_store_hash_cmp(const void *unused_cmp_data,
1626 const void *entry, const void *entry_or_key,
1627 const void *keydata)
1628{
1629 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1630 const char *name = keydata ? keydata : e2->name;
1631
1632 return strcmp(e1->name, name);
1633}
1634
1635static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1636 const char *name, struct ref_store *refs)
1637{
1638 struct ref_store_hash_entry *entry;
1639
1640 FLEX_ALLOC_STR(entry, name, name);
1641 hashmap_entry_init(entry, strhash(name));
1642 entry->refs = refs;
1643 return entry;
1644}
1645
1646/* A hashmap of ref_stores, stored by submodule name: */
1647static struct hashmap submodule_ref_stores;
1648
1649/* A hashmap of ref_stores, stored by worktree id: */
1650static struct hashmap worktree_ref_stores;
1651
1652/*
1653 * Look up a ref store by name. If that ref_store hasn't been
1654 * registered yet, return NULL.
1655 */
1656static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1657 const char *name)
1658{
1659 struct ref_store_hash_entry *entry;
1660
1661 if (!map->tablesize)
1662 /* It's initialized on demand in register_ref_store(). */
1663 return NULL;
1664
1665 entry = hashmap_get_from_hash(map, strhash(name), name);
1666 return entry ? entry->refs : NULL;
1667}
1668
1669/*
1670 * Create, record, and return a ref_store instance for the specified
1671 * gitdir.
1672 */
1673static struct ref_store *ref_store_init(const char *gitdir,
1674 unsigned int flags)
1675{
1676 const char *be_name = "files";
1677 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1678 struct ref_store *refs;
1679
1680 if (!be)
1681 BUG("reference backend %s is unknown", be_name);
1682
1683 refs = be->init(gitdir, flags);
1684 return refs;
1685}
1686
1687struct ref_store *get_main_ref_store(struct repository *r)
1688{
1689 if (r->refs)
1690 return r->refs;
1691
1692 if (!r->gitdir)
1693 BUG("attempting to get main_ref_store outside of repository");
1694
1695 r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
1696 return r->refs;
1697}
1698
1699/*
1700 * Associate a ref store with a name. It is a fatal error to call this
1701 * function twice for the same name.
1702 */
1703static void register_ref_store_map(struct hashmap *map,
1704 const char *type,
1705 struct ref_store *refs,
1706 const char *name)
1707{
1708 if (!map->tablesize)
1709 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1710
1711 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1712 BUG("%s ref_store '%s' initialized twice", type, name);
1713}
1714
1715struct ref_store *get_submodule_ref_store(const char *submodule)
1716{
1717 struct strbuf submodule_sb = STRBUF_INIT;
1718 struct ref_store *refs;
1719 char *to_free = NULL;
1720 size_t len;
1721
1722 if (!submodule)
1723 return NULL;
1724
1725 len = strlen(submodule);
1726 while (len && is_dir_sep(submodule[len - 1]))
1727 len--;
1728 if (!len)
1729 return NULL;
1730
1731 if (submodule[len])
1732 /* We need to strip off one or more trailing slashes */
1733 submodule = to_free = xmemdupz(submodule, len);
1734
1735 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1736 if (refs)
1737 goto done;
1738
1739 strbuf_addstr(&submodule_sb, submodule);
1740 if (!is_nonbare_repository_dir(&submodule_sb))
1741 goto done;
1742
1743 if (submodule_to_gitdir(&submodule_sb, submodule))
1744 goto done;
1745
1746 /* assume that add_submodule_odb() has been called */
1747 refs = ref_store_init(submodule_sb.buf,
1748 REF_STORE_READ | REF_STORE_ODB);
1749 register_ref_store_map(&submodule_ref_stores, "submodule",
1750 refs, submodule);
1751
1752done:
1753 strbuf_release(&submodule_sb);
1754 free(to_free);
1755
1756 return refs;
1757}
1758
1759struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1760{
1761 struct ref_store *refs;
1762 const char *id;
1763
1764 if (wt->is_current)
1765 return get_main_ref_store(the_repository);
1766
1767 id = wt->id ? wt->id : "/";
1768 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1769 if (refs)
1770 return refs;
1771
1772 if (wt->id)
1773 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1774 REF_STORE_ALL_CAPS);
1775 else
1776 refs = ref_store_init(get_git_common_dir(),
1777 REF_STORE_ALL_CAPS);
1778
1779 if (refs)
1780 register_ref_store_map(&worktree_ref_stores, "worktree",
1781 refs, id);
1782 return refs;
1783}
1784
1785void base_ref_store_init(struct ref_store *refs,
1786 const struct ref_storage_be *be)
1787{
1788 refs->be = be;
1789}
1790
1791/* backend functions */
1792int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1793{
1794 return refs->be->pack_refs(refs, flags);
1795}
1796
1797int refs_peel_ref(struct ref_store *refs, const char *refname,
1798 struct object_id *oid)
1799{
1800 int flag;
1801 struct object_id base;
1802
1803 if (current_ref_iter && current_ref_iter->refname == refname) {
1804 struct object_id peeled;
1805
1806 if (ref_iterator_peel(current_ref_iter, &peeled))
1807 return -1;
1808 oidcpy(oid, &peeled);
1809 return 0;
1810 }
1811
1812 if (refs_read_ref_full(refs, refname,
1813 RESOLVE_REF_READING, &base, &flag))
1814 return -1;
1815
1816 return peel_object(&base, oid);
1817}
1818
1819int peel_ref(const char *refname, struct object_id *oid)
1820{
1821 return refs_peel_ref(get_main_ref_store(the_repository), refname, oid);
1822}
1823
1824int refs_create_symref(struct ref_store *refs,
1825 const char *ref_target,
1826 const char *refs_heads_master,
1827 const char *logmsg)
1828{
1829 return refs->be->create_symref(refs, ref_target,
1830 refs_heads_master,
1831 logmsg);
1832}
1833
1834int create_symref(const char *ref_target, const char *refs_heads_master,
1835 const char *logmsg)
1836{
1837 return refs_create_symref(get_main_ref_store(the_repository), ref_target,
1838 refs_heads_master, logmsg);
1839}
1840
1841int ref_update_reject_duplicates(struct string_list *refnames,
1842 struct strbuf *err)
1843{
1844 size_t i, n = refnames->nr;
1845
1846 assert(err);
1847
1848 for (i = 1; i < n; i++) {
1849 int cmp = strcmp(refnames->items[i - 1].string,
1850 refnames->items[i].string);
1851
1852 if (!cmp) {
1853 strbuf_addf(err,
1854 _("multiple updates for ref '%s' not allowed"),
1855 refnames->items[i].string);
1856 return 1;
1857 } else if (cmp > 0) {
1858 BUG("ref_update_reject_duplicates() received unsorted list");
1859 }
1860 }
1861 return 0;
1862}
1863
1864int ref_transaction_prepare(struct ref_transaction *transaction,
1865 struct strbuf *err)
1866{
1867 struct ref_store *refs = transaction->ref_store;
1868
1869 switch (transaction->state) {
1870 case REF_TRANSACTION_OPEN:
1871 /* Good. */
1872 break;
1873 case REF_TRANSACTION_PREPARED:
1874 BUG("prepare called twice on reference transaction");
1875 break;
1876 case REF_TRANSACTION_CLOSED:
1877 BUG("prepare called on a closed reference transaction");
1878 break;
1879 default:
1880 BUG("unexpected reference transaction state");
1881 break;
1882 }
1883
1884 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1885 strbuf_addstr(err,
1886 _("ref updates forbidden inside quarantine environment"));
1887 return -1;
1888 }
1889
1890 return refs->be->transaction_prepare(refs, transaction, err);
1891}
1892
1893int ref_transaction_abort(struct ref_transaction *transaction,
1894 struct strbuf *err)
1895{
1896 struct ref_store *refs = transaction->ref_store;
1897 int ret = 0;
1898
1899 switch (transaction->state) {
1900 case REF_TRANSACTION_OPEN:
1901 /* No need to abort explicitly. */
1902 break;
1903 case REF_TRANSACTION_PREPARED:
1904 ret = refs->be->transaction_abort(refs, transaction, err);
1905 break;
1906 case REF_TRANSACTION_CLOSED:
1907 BUG("abort called on a closed reference transaction");
1908 break;
1909 default:
1910 BUG("unexpected reference transaction state");
1911 break;
1912 }
1913
1914 ref_transaction_free(transaction);
1915 return ret;
1916}
1917
1918int ref_transaction_commit(struct ref_transaction *transaction,
1919 struct strbuf *err)
1920{
1921 struct ref_store *refs = transaction->ref_store;
1922 int ret;
1923
1924 switch (transaction->state) {
1925 case REF_TRANSACTION_OPEN:
1926 /* Need to prepare first. */
1927 ret = ref_transaction_prepare(transaction, err);
1928 if (ret)
1929 return ret;
1930 break;
1931 case REF_TRANSACTION_PREPARED:
1932 /* Fall through to finish. */
1933 break;
1934 case REF_TRANSACTION_CLOSED:
1935 BUG("commit called on a closed reference transaction");
1936 break;
1937 default:
1938 BUG("unexpected reference transaction state");
1939 break;
1940 }
1941
1942 return refs->be->transaction_finish(refs, transaction, err);
1943}
1944
1945int refs_verify_refname_available(struct ref_store *refs,
1946 const char *refname,
1947 const struct string_list *extras,
1948 const struct string_list *skip,
1949 struct strbuf *err)
1950{
1951 const char *slash;
1952 const char *extra_refname;
1953 struct strbuf dirname = STRBUF_INIT;
1954 struct strbuf referent = STRBUF_INIT;
1955 struct object_id oid;
1956 unsigned int type;
1957 struct ref_iterator *iter;
1958 int ok;
1959 int ret = -1;
1960
1961 /*
1962 * For the sake of comments in this function, suppose that
1963 * refname is "refs/foo/bar".
1964 */
1965
1966 assert(err);
1967
1968 strbuf_grow(&dirname, strlen(refname) + 1);
1969 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1970 /* Expand dirname to the new prefix, not including the trailing slash: */
1971 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1972
1973 /*
1974 * We are still at a leading dir of the refname (e.g.,
1975 * "refs/foo"; if there is a reference with that name,
1976 * it is a conflict, *unless* it is in skip.
1977 */
1978 if (skip && string_list_has_string(skip, dirname.buf))
1979 continue;
1980
1981 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
1982 strbuf_addf(err, _("'%s' exists; cannot create '%s'"),
1983 dirname.buf, refname);
1984 goto cleanup;
1985 }
1986
1987 if (extras && string_list_has_string(extras, dirname.buf)) {
1988 strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"),
1989 refname, dirname.buf);
1990 goto cleanup;
1991 }
1992 }
1993
1994 /*
1995 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1996 * There is no point in searching for a reference with that
1997 * name, because a refname isn't considered to conflict with
1998 * itself. But we still need to check for references whose
1999 * names are in the "refs/foo/bar/" namespace, because they
2000 * *do* conflict.
2001 */
2002 strbuf_addstr(&dirname, refname + dirname.len);
2003 strbuf_addch(&dirname, '/');
2004
2005 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
2006 DO_FOR_EACH_INCLUDE_BROKEN);
2007 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
2008 if (skip &&
2009 string_list_has_string(skip, iter->refname))
2010 continue;
2011
2012 strbuf_addf(err, _("'%s' exists; cannot create '%s'"),
2013 iter->refname, refname);
2014 ref_iterator_abort(iter);
2015 goto cleanup;
2016 }
2017
2018 if (ok != ITER_DONE)
2019 BUG("error while iterating over references");
2020
2021 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
2022 if (extra_refname)
2023 strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"),
2024 refname, extra_refname);
2025 else
2026 ret = 0;
2027
2028cleanup:
2029 strbuf_release(&referent);
2030 strbuf_release(&dirname);
2031 return ret;
2032}
2033
2034int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2035{
2036 struct ref_iterator *iter;
2037
2038 iter = refs->be->reflog_iterator_begin(refs);
2039
2040 return do_for_each_ref_iterator(iter, fn, cb_data);
2041}
2042
2043int for_each_reflog(each_ref_fn fn, void *cb_data)
2044{
2045 return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
2046}
2047
2048int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
2049 const char *refname,
2050 each_reflog_ent_fn fn,
2051 void *cb_data)
2052{
2053 return refs->be->for_each_reflog_ent_reverse(refs, refname,
2054 fn, cb_data);
2055}
2056
2057int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
2058 void *cb_data)
2059{
2060 return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository),
2061 refname, fn, cb_data);
2062}
2063
2064int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
2065 each_reflog_ent_fn fn, void *cb_data)
2066{
2067 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
2068}
2069
2070int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
2071 void *cb_data)
2072{
2073 return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname,
2074 fn, cb_data);
2075}
2076
2077int refs_reflog_exists(struct ref_store *refs, const char *refname)
2078{
2079 return refs->be->reflog_exists(refs, refname);
2080}
2081
2082int reflog_exists(const char *refname)
2083{
2084 return refs_reflog_exists(get_main_ref_store(the_repository), refname);
2085}
2086
2087int refs_create_reflog(struct ref_store *refs, const char *refname,
2088 int force_create, struct strbuf *err)
2089{
2090 return refs->be->create_reflog(refs, refname, force_create, err);
2091}
2092
2093int safe_create_reflog(const char *refname, int force_create,
2094 struct strbuf *err)
2095{
2096 return refs_create_reflog(get_main_ref_store(the_repository), refname,
2097 force_create, err);
2098}
2099
2100int refs_delete_reflog(struct ref_store *refs, const char *refname)
2101{
2102 return refs->be->delete_reflog(refs, refname);
2103}
2104
2105int delete_reflog(const char *refname)
2106{
2107 return refs_delete_reflog(get_main_ref_store(the_repository), refname);
2108}
2109
2110int refs_reflog_expire(struct ref_store *refs,
2111 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->be->reflog_expire(refs, refname, oid, flags,
2119 prepare_fn, should_prune_fn,
2120 cleanup_fn, policy_cb_data);
2121}
2122
2123int reflog_expire(const char *refname, const struct object_id *oid,
2124 unsigned int flags,
2125 reflog_expiry_prepare_fn prepare_fn,
2126 reflog_expiry_should_prune_fn should_prune_fn,
2127 reflog_expiry_cleanup_fn cleanup_fn,
2128 void *policy_cb_data)
2129{
2130 return refs_reflog_expire(get_main_ref_store(the_repository),
2131 refname, oid, flags,
2132 prepare_fn, should_prune_fn,
2133 cleanup_fn, policy_cb_data);
2134}
2135
2136int initial_ref_transaction_commit(struct ref_transaction *transaction,
2137 struct strbuf *err)
2138{
2139 struct ref_store *refs = transaction->ref_store;
2140
2141 return refs->be->initial_transaction_commit(refs, transaction, err);
2142}
2143
2144int refs_delete_refs(struct ref_store *refs, const char *msg,
2145 struct string_list *refnames, unsigned int flags)
2146{
2147 return refs->be->delete_refs(refs, msg, refnames, flags);
2148}
2149
2150int delete_refs(const char *msg, struct string_list *refnames,
2151 unsigned int flags)
2152{
2153 return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags);
2154}
2155
2156int refs_rename_ref(struct ref_store *refs, const char *oldref,
2157 const char *newref, const char *logmsg)
2158{
2159 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2160}
2161
2162int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2163{
2164 return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2165}
2166
2167int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2168 const char *newref, const char *logmsg)
2169{
2170 return refs->be->copy_ref(refs, oldref, newref, logmsg);
2171}
2172
2173int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2174{
2175 return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2176}