Merge branch 'ls/no-double-utf8-author-name' of ../git-gui into ls/git-gui-no-double...
[git/git.git] / refs.c
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
17 /*
18 * List of all available backends
19 */
20 static struct ref_storage_be *refs_backends = &refs_be_files;
21
22 static struct ref_storage_be *find_ref_storage_backend(const char *name)
23 {
24 struct ref_storage_be *be;
25 for (be = refs_backends; be; be = be->next)
26 if (!strcmp(be->name, name))
27 return be;
28 return NULL;
29 }
30
31 int ref_storage_backend_exists(const char *name)
32 {
33 return find_ref_storage_backend(name) != NULL;
34 }
35
36 /*
37 * How to handle various characters in refnames:
38 * 0: An acceptable character for refs
39 * 1: End-of-component
40 * 2: ., look for a preceding . to reject .. in refs
41 * 3: {, look for a preceding @ to reject @{ in refs
42 * 4: A bad character: ASCII control characters, and
43 * ":", "?", "[", "\", "^", "~", SP, or TAB
44 * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
45 */
46 static unsigned char refname_disposition[256] = {
47 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
48 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
49 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
50 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
51 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
52 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
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, 3, 0, 0, 4, 4
55 };
56
57 /*
58 * Try to read one refname component from the front of refname.
59 * Return the length of the component found, or -1 if the component is
60 * not legal. It is legal if it is something reasonable to have under
61 * ".git/refs/"; We do not like it if:
62 *
63 * - any path component of it begins with ".", or
64 * - it has double dots "..", or
65 * - it has ASCII control characters, or
66 * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
67 * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
68 * - it ends with a "/", or
69 * - it ends with ".lock", or
70 * - it contains a "@{" portion
71 */
72 static int check_refname_component(const char *refname, int *flags)
73 {
74 const char *cp;
75 char last = '\0';
76
77 for (cp = refname; ; cp++) {
78 int ch = *cp & 255;
79 unsigned char disp = refname_disposition[ch];
80 switch (disp) {
81 case 1:
82 goto out;
83 case 2:
84 if (last == '.')
85 return -1; /* Refname contains "..". */
86 break;
87 case 3:
88 if (last == '@')
89 return -1; /* Refname contains "@{". */
90 break;
91 case 4:
92 return -1;
93 case 5:
94 if (!(*flags & REFNAME_REFSPEC_PATTERN))
95 return -1; /* refspec can't be a pattern */
96
97 /*
98 * Unset the pattern flag so that we only accept
99 * a single asterisk for one side of refspec.
100 */
101 *flags &= ~ REFNAME_REFSPEC_PATTERN;
102 break;
103 }
104 last = ch;
105 }
106 out:
107 if (cp == refname)
108 return 0; /* Component has zero length. */
109 if (refname[0] == '.')
110 return -1; /* Component starts with '.'. */
111 if (cp - refname >= LOCK_SUFFIX_LEN &&
112 !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
113 return -1; /* Refname ends with ".lock". */
114 return cp - refname;
115 }
116
117 int check_refname_format(const char *refname, int flags)
118 {
119 int component_len, component_count = 0;
120
121 if (!strcmp(refname, "@"))
122 /* Refname is a single character '@'. */
123 return -1;
124
125 while (1) {
126 /* We are at the start of a path component. */
127 component_len = check_refname_component(refname, &flags);
128 if (component_len <= 0)
129 return -1;
130
131 component_count++;
132 if (refname[component_len] == '\0')
133 break;
134 /* Skip to next component. */
135 refname += component_len + 1;
136 }
137
138 if (refname[component_len - 1] == '.')
139 return -1; /* Refname ends with '.'. */
140 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
141 return -1; /* Refname has only one component. */
142 return 0;
143 }
144
145 int refname_is_safe(const char *refname)
146 {
147 const char *rest;
148
149 if (skip_prefix(refname, "refs/", &rest)) {
150 char *buf;
151 int result;
152 size_t restlen = strlen(rest);
153
154 /* rest must not be empty, or start or end with "/" */
155 if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
156 return 0;
157
158 /*
159 * Does the refname try to escape refs/?
160 * For example: refs/foo/../bar is safe but refs/foo/../../bar
161 * is not.
162 */
163 buf = xmallocz(restlen);
164 result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
165 free(buf);
166 return result;
167 }
168
169 do {
170 if (!isupper(*refname) && *refname != '_')
171 return 0;
172 refname++;
173 } while (*refname);
174 return 1;
175 }
176
177 /*
178 * Return true if refname, which has the specified oid and flags, can
179 * be resolved to an object in the database. If the referred-to object
180 * does not exist, emit a warning and return false.
181 */
182 int ref_resolves_to_object(const char *refname,
183 const struct object_id *oid,
184 unsigned int flags)
185 {
186 if (flags & REF_ISBROKEN)
187 return 0;
188 if (!has_sha1_file(oid->hash)) {
189 error("%s does not point to a valid object!", refname);
190 return 0;
191 }
192 return 1;
193 }
194
195 char *refs_resolve_refdup(struct ref_store *refs,
196 const char *refname, int resolve_flags,
197 struct object_id *oid, int *flags)
198 {
199 const char *result;
200
201 result = refs_resolve_ref_unsafe(refs, refname, resolve_flags,
202 oid, flags);
203 return xstrdup_or_null(result);
204 }
205
206 char *resolve_refdup(const char *refname, int resolve_flags,
207 struct object_id *oid, int *flags)
208 {
209 return refs_resolve_refdup(get_main_ref_store(),
210 refname, resolve_flags,
211 oid, flags);
212 }
213
214 /* The argument to filter_refs */
215 struct ref_filter {
216 const char *pattern;
217 each_ref_fn *fn;
218 void *cb_data;
219 };
220
221 int refs_read_ref_full(struct ref_store *refs, const char *refname,
222 int resolve_flags, struct object_id *oid, int *flags)
223 {
224 if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, oid, flags))
225 return 0;
226 return -1;
227 }
228
229 int read_ref_full(const char *refname, int resolve_flags, struct object_id *oid, int *flags)
230 {
231 return refs_read_ref_full(get_main_ref_store(), refname,
232 resolve_flags, oid, flags);
233 }
234
235 int read_ref(const char *refname, struct object_id *oid)
236 {
237 return read_ref_full(refname, RESOLVE_REF_READING, oid, NULL);
238 }
239
240 int ref_exists(const char *refname)
241 {
242 return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, NULL, NULL);
243 }
244
245 static int filter_refs(const char *refname, const struct object_id *oid,
246 int flags, void *data)
247 {
248 struct ref_filter *filter = (struct ref_filter *)data;
249
250 if (wildmatch(filter->pattern, refname, 0))
251 return 0;
252 return filter->fn(refname, oid, flags, filter->cb_data);
253 }
254
255 enum peel_status peel_object(const struct object_id *name, struct object_id *oid)
256 {
257 struct object *o = lookup_unknown_object(name->hash);
258
259 if (o->type == OBJ_NONE) {
260 int type = sha1_object_info(name->hash, NULL);
261 if (type < 0 || !object_as_type(o, type, 0))
262 return PEEL_INVALID;
263 }
264
265 if (o->type != OBJ_TAG)
266 return PEEL_NON_TAG;
267
268 o = deref_tag_noverify(o);
269 if (!o)
270 return PEEL_INVALID;
271
272 oidcpy(oid, &o->oid);
273 return PEEL_PEELED;
274 }
275
276 struct warn_if_dangling_data {
277 FILE *fp;
278 const char *refname;
279 const struct string_list *refnames;
280 const char *msg_fmt;
281 };
282
283 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
284 int flags, void *cb_data)
285 {
286 struct warn_if_dangling_data *d = cb_data;
287 const char *resolves_to;
288
289 if (!(flags & REF_ISSYMREF))
290 return 0;
291
292 resolves_to = resolve_ref_unsafe(refname, 0, NULL, NULL);
293 if (!resolves_to
294 || (d->refname
295 ? strcmp(resolves_to, d->refname)
296 : !string_list_has_string(d->refnames, resolves_to))) {
297 return 0;
298 }
299
300 fprintf(d->fp, d->msg_fmt, refname);
301 fputc('\n', d->fp);
302 return 0;
303 }
304
305 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
306 {
307 struct warn_if_dangling_data data;
308
309 data.fp = fp;
310 data.refname = refname;
311 data.refnames = NULL;
312 data.msg_fmt = msg_fmt;
313 for_each_rawref(warn_if_dangling_symref, &data);
314 }
315
316 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
317 {
318 struct warn_if_dangling_data data;
319
320 data.fp = fp;
321 data.refname = NULL;
322 data.refnames = refnames;
323 data.msg_fmt = msg_fmt;
324 for_each_rawref(warn_if_dangling_symref, &data);
325 }
326
327 int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
328 {
329 return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
330 }
331
332 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
333 {
334 return refs_for_each_tag_ref(get_main_ref_store(), fn, cb_data);
335 }
336
337 int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
338 {
339 return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
340 }
341
342 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
343 {
344 return refs_for_each_branch_ref(get_main_ref_store(), fn, cb_data);
345 }
346
347 int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
348 {
349 return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
350 }
351
352 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
353 {
354 return refs_for_each_remote_ref(get_main_ref_store(), fn, cb_data);
355 }
356
357 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
358 {
359 struct strbuf buf = STRBUF_INIT;
360 int ret = 0;
361 struct object_id oid;
362 int flag;
363
364 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
365 if (!read_ref_full(buf.buf, RESOLVE_REF_READING, &oid, &flag))
366 ret = fn(buf.buf, &oid, flag, cb_data);
367 strbuf_release(&buf);
368
369 return ret;
370 }
371
372 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
373 const char *prefix, void *cb_data)
374 {
375 struct strbuf real_pattern = STRBUF_INIT;
376 struct ref_filter filter;
377 int ret;
378
379 if (!prefix && !starts_with(pattern, "refs/"))
380 strbuf_addstr(&real_pattern, "refs/");
381 else if (prefix)
382 strbuf_addstr(&real_pattern, prefix);
383 strbuf_addstr(&real_pattern, pattern);
384
385 if (!has_glob_specials(pattern)) {
386 /* Append implied '/' '*' if not present. */
387 strbuf_complete(&real_pattern, '/');
388 /* No need to check for '*', there is none. */
389 strbuf_addch(&real_pattern, '*');
390 }
391
392 filter.pattern = real_pattern.buf;
393 filter.fn = fn;
394 filter.cb_data = cb_data;
395 ret = for_each_ref(filter_refs, &filter);
396
397 strbuf_release(&real_pattern);
398 return ret;
399 }
400
401 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
402 {
403 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
404 }
405
406 const char *prettify_refname(const char *name)
407 {
408 if (skip_prefix(name, "refs/heads/", &name) ||
409 skip_prefix(name, "refs/tags/", &name) ||
410 skip_prefix(name, "refs/remotes/", &name))
411 ; /* nothing */
412 return name;
413 }
414
415 static const char *ref_rev_parse_rules[] = {
416 "%.*s",
417 "refs/%.*s",
418 "refs/tags/%.*s",
419 "refs/heads/%.*s",
420 "refs/remotes/%.*s",
421 "refs/remotes/%.*s/HEAD",
422 NULL
423 };
424
425 int refname_match(const char *abbrev_name, const char *full_name)
426 {
427 const char **p;
428 const int abbrev_name_len = strlen(abbrev_name);
429
430 for (p = ref_rev_parse_rules; *p; p++) {
431 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
432 return 1;
433 }
434 }
435
436 return 0;
437 }
438
439 /*
440 * *string and *len will only be substituted, and *string returned (for
441 * later free()ing) if the string passed in is a magic short-hand form
442 * to name a branch.
443 */
444 static char *substitute_branch_name(const char **string, int *len)
445 {
446 struct strbuf buf = STRBUF_INIT;
447 int ret = interpret_branch_name(*string, *len, &buf, 0);
448
449 if (ret == *len) {
450 size_t size;
451 *string = strbuf_detach(&buf, &size);
452 *len = size;
453 return (char *)*string;
454 }
455
456 return NULL;
457 }
458
459 int dwim_ref(const char *str, int len, struct object_id *oid, char **ref)
460 {
461 char *last_branch = substitute_branch_name(&str, &len);
462 int refs_found = expand_ref(str, len, oid, ref);
463 free(last_branch);
464 return refs_found;
465 }
466
467 int expand_ref(const char *str, int len, struct object_id *oid, char **ref)
468 {
469 const char **p, *r;
470 int refs_found = 0;
471 struct strbuf fullref = STRBUF_INIT;
472
473 *ref = NULL;
474 for (p = ref_rev_parse_rules; *p; p++) {
475 struct object_id oid_from_ref;
476 struct object_id *this_result;
477 int flag;
478
479 this_result = refs_found ? &oid_from_ref : oid;
480 strbuf_reset(&fullref);
481 strbuf_addf(&fullref, *p, len, str);
482 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
483 this_result, &flag);
484 if (r) {
485 if (!refs_found++)
486 *ref = xstrdup(r);
487 if (!warn_ambiguous_refs)
488 break;
489 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
490 warning("ignoring dangling symref %s.", fullref.buf);
491 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
492 warning("ignoring broken ref %s.", fullref.buf);
493 }
494 }
495 strbuf_release(&fullref);
496 return refs_found;
497 }
498
499 int dwim_log(const char *str, int len, struct object_id *oid, char **log)
500 {
501 char *last_branch = substitute_branch_name(&str, &len);
502 const char **p;
503 int logs_found = 0;
504 struct strbuf path = STRBUF_INIT;
505
506 *log = NULL;
507 for (p = ref_rev_parse_rules; *p; p++) {
508 struct object_id hash;
509 const char *ref, *it;
510
511 strbuf_reset(&path);
512 strbuf_addf(&path, *p, len, str);
513 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
514 &hash, NULL);
515 if (!ref)
516 continue;
517 if (reflog_exists(path.buf))
518 it = path.buf;
519 else if (strcmp(ref, path.buf) && reflog_exists(ref))
520 it = ref;
521 else
522 continue;
523 if (!logs_found++) {
524 *log = xstrdup(it);
525 oidcpy(oid, &hash);
526 }
527 if (!warn_ambiguous_refs)
528 break;
529 }
530 strbuf_release(&path);
531 free(last_branch);
532 return logs_found;
533 }
534
535 static int is_per_worktree_ref(const char *refname)
536 {
537 return !strcmp(refname, "HEAD") ||
538 starts_with(refname, "refs/bisect/");
539 }
540
541 static int is_pseudoref_syntax(const char *refname)
542 {
543 const char *c;
544
545 for (c = refname; *c; c++) {
546 if (!isupper(*c) && *c != '-' && *c != '_')
547 return 0;
548 }
549
550 return 1;
551 }
552
553 enum ref_type ref_type(const char *refname)
554 {
555 if (is_per_worktree_ref(refname))
556 return REF_TYPE_PER_WORKTREE;
557 if (is_pseudoref_syntax(refname))
558 return REF_TYPE_PSEUDOREF;
559 return REF_TYPE_NORMAL;
560 }
561
562 long get_files_ref_lock_timeout_ms(void)
563 {
564 static int configured = 0;
565
566 /* The default timeout is 100 ms: */
567 static int timeout_ms = 100;
568
569 if (!configured) {
570 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
571 configured = 1;
572 }
573
574 return timeout_ms;
575 }
576
577 static int write_pseudoref(const char *pseudoref, const struct object_id *oid,
578 const struct object_id *old_oid, struct strbuf *err)
579 {
580 const char *filename;
581 int fd;
582 static struct lock_file lock;
583 struct strbuf buf = STRBUF_INIT;
584 int ret = -1;
585
586 if (!oid)
587 return 0;
588
589 strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
590
591 filename = git_path("%s", pseudoref);
592 fd = hold_lock_file_for_update_timeout(&lock, filename,
593 LOCK_DIE_ON_ERROR,
594 get_files_ref_lock_timeout_ms());
595 if (fd < 0) {
596 strbuf_addf(err, "could not open '%s' for writing: %s",
597 filename, strerror(errno));
598 goto done;
599 }
600
601 if (old_oid) {
602 struct object_id actual_old_oid;
603
604 if (read_ref(pseudoref, &actual_old_oid))
605 die("could not read ref '%s'", pseudoref);
606 if (oidcmp(&actual_old_oid, old_oid)) {
607 strbuf_addf(err, "unexpected sha1 when writing '%s'", pseudoref);
608 rollback_lock_file(&lock);
609 goto done;
610 }
611 }
612
613 if (write_in_full(fd, buf.buf, buf.len) < 0) {
614 strbuf_addf(err, "could not write to '%s'", filename);
615 rollback_lock_file(&lock);
616 goto done;
617 }
618
619 commit_lock_file(&lock);
620 ret = 0;
621 done:
622 strbuf_release(&buf);
623 return ret;
624 }
625
626 static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
627 {
628 static struct lock_file lock;
629 const char *filename;
630
631 filename = git_path("%s", pseudoref);
632
633 if (old_oid && !is_null_oid(old_oid)) {
634 int fd;
635 struct object_id actual_old_oid;
636
637 fd = hold_lock_file_for_update_timeout(
638 &lock, filename, LOCK_DIE_ON_ERROR,
639 get_files_ref_lock_timeout_ms());
640 if (fd < 0)
641 die_errno(_("Could not open '%s' for writing"), filename);
642 if (read_ref(pseudoref, &actual_old_oid))
643 die("could not read ref '%s'", pseudoref);
644 if (oidcmp(&actual_old_oid, old_oid)) {
645 warning("Unexpected sha1 when deleting %s", pseudoref);
646 rollback_lock_file(&lock);
647 return -1;
648 }
649
650 unlink(filename);
651 rollback_lock_file(&lock);
652 } else {
653 unlink(filename);
654 }
655
656 return 0;
657 }
658
659 int refs_delete_ref(struct ref_store *refs, const char *msg,
660 const char *refname,
661 const struct object_id *old_oid,
662 unsigned int flags)
663 {
664 struct ref_transaction *transaction;
665 struct strbuf err = STRBUF_INIT;
666
667 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
668 assert(refs == get_main_ref_store());
669 return delete_pseudoref(refname, old_oid);
670 }
671
672 transaction = ref_store_transaction_begin(refs, &err);
673 if (!transaction ||
674 ref_transaction_delete(transaction, refname, old_oid,
675 flags, msg, &err) ||
676 ref_transaction_commit(transaction, &err)) {
677 error("%s", err.buf);
678 ref_transaction_free(transaction);
679 strbuf_release(&err);
680 return 1;
681 }
682 ref_transaction_free(transaction);
683 strbuf_release(&err);
684 return 0;
685 }
686
687 int delete_ref(const char *msg, const char *refname,
688 const struct object_id *old_oid, unsigned int flags)
689 {
690 return refs_delete_ref(get_main_ref_store(), msg, refname,
691 old_oid, flags);
692 }
693
694 int copy_reflog_msg(char *buf, const char *msg)
695 {
696 char *cp = buf;
697 char c;
698 int wasspace = 1;
699
700 *cp++ = '\t';
701 while ((c = *msg++)) {
702 if (wasspace && isspace(c))
703 continue;
704 wasspace = isspace(c);
705 if (wasspace)
706 c = ' ';
707 *cp++ = c;
708 }
709 while (buf < cp && isspace(cp[-1]))
710 cp--;
711 *cp++ = '\n';
712 return cp - buf;
713 }
714
715 int should_autocreate_reflog(const char *refname)
716 {
717 switch (log_all_ref_updates) {
718 case LOG_REFS_ALWAYS:
719 return 1;
720 case LOG_REFS_NORMAL:
721 return starts_with(refname, "refs/heads/") ||
722 starts_with(refname, "refs/remotes/") ||
723 starts_with(refname, "refs/notes/") ||
724 !strcmp(refname, "HEAD");
725 default:
726 return 0;
727 }
728 }
729
730 int is_branch(const char *refname)
731 {
732 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
733 }
734
735 struct read_ref_at_cb {
736 const char *refname;
737 timestamp_t at_time;
738 int cnt;
739 int reccnt;
740 struct object_id *oid;
741 int found_it;
742
743 struct object_id ooid;
744 struct object_id noid;
745 int tz;
746 timestamp_t date;
747 char **msg;
748 timestamp_t *cutoff_time;
749 int *cutoff_tz;
750 int *cutoff_cnt;
751 };
752
753 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
754 const char *email, timestamp_t timestamp, int tz,
755 const char *message, void *cb_data)
756 {
757 struct read_ref_at_cb *cb = cb_data;
758
759 cb->reccnt++;
760 cb->tz = tz;
761 cb->date = timestamp;
762
763 if (timestamp <= cb->at_time || cb->cnt == 0) {
764 if (cb->msg)
765 *cb->msg = xstrdup(message);
766 if (cb->cutoff_time)
767 *cb->cutoff_time = timestamp;
768 if (cb->cutoff_tz)
769 *cb->cutoff_tz = tz;
770 if (cb->cutoff_cnt)
771 *cb->cutoff_cnt = cb->reccnt - 1;
772 /*
773 * we have not yet updated cb->[n|o]oid so they still
774 * hold the values for the previous record.
775 */
776 if (!is_null_oid(&cb->ooid)) {
777 oidcpy(cb->oid, noid);
778 if (oidcmp(&cb->ooid, noid))
779 warning("Log for ref %s has gap after %s.",
780 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
781 }
782 else if (cb->date == cb->at_time)
783 oidcpy(cb->oid, noid);
784 else if (oidcmp(noid, cb->oid))
785 warning("Log for ref %s unexpectedly ended on %s.",
786 cb->refname, show_date(cb->date, cb->tz,
787 DATE_MODE(RFC2822)));
788 oidcpy(&cb->ooid, ooid);
789 oidcpy(&cb->noid, noid);
790 cb->found_it = 1;
791 return 1;
792 }
793 oidcpy(&cb->ooid, ooid);
794 oidcpy(&cb->noid, noid);
795 if (cb->cnt > 0)
796 cb->cnt--;
797 return 0;
798 }
799
800 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
801 const char *email, timestamp_t timestamp,
802 int tz, const char *message, void *cb_data)
803 {
804 struct read_ref_at_cb *cb = cb_data;
805
806 if (cb->msg)
807 *cb->msg = xstrdup(message);
808 if (cb->cutoff_time)
809 *cb->cutoff_time = timestamp;
810 if (cb->cutoff_tz)
811 *cb->cutoff_tz = tz;
812 if (cb->cutoff_cnt)
813 *cb->cutoff_cnt = cb->reccnt;
814 oidcpy(cb->oid, ooid);
815 if (is_null_oid(cb->oid))
816 oidcpy(cb->oid, noid);
817 /* We just want the first entry */
818 return 1;
819 }
820
821 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
822 struct object_id *oid, char **msg,
823 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
824 {
825 struct read_ref_at_cb cb;
826
827 memset(&cb, 0, sizeof(cb));
828 cb.refname = refname;
829 cb.at_time = at_time;
830 cb.cnt = cnt;
831 cb.msg = msg;
832 cb.cutoff_time = cutoff_time;
833 cb.cutoff_tz = cutoff_tz;
834 cb.cutoff_cnt = cutoff_cnt;
835 cb.oid = oid;
836
837 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
838
839 if (!cb.reccnt) {
840 if (flags & GET_OID_QUIETLY)
841 exit(128);
842 else
843 die("Log for %s is empty.", refname);
844 }
845 if (cb.found_it)
846 return 0;
847
848 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
849
850 return 1;
851 }
852
853 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
854 struct strbuf *err)
855 {
856 struct ref_transaction *tr;
857 assert(err);
858
859 tr = xcalloc(1, sizeof(struct ref_transaction));
860 tr->ref_store = refs;
861 return tr;
862 }
863
864 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
865 {
866 return ref_store_transaction_begin(get_main_ref_store(), err);
867 }
868
869 void ref_transaction_free(struct ref_transaction *transaction)
870 {
871 size_t i;
872
873 if (!transaction)
874 return;
875
876 switch (transaction->state) {
877 case REF_TRANSACTION_OPEN:
878 case REF_TRANSACTION_CLOSED:
879 /* OK */
880 break;
881 case REF_TRANSACTION_PREPARED:
882 die("BUG: free called on a prepared reference transaction");
883 break;
884 default:
885 die("BUG: unexpected reference transaction state");
886 break;
887 }
888
889 for (i = 0; i < transaction->nr; i++) {
890 free(transaction->updates[i]->msg);
891 free(transaction->updates[i]);
892 }
893 free(transaction->updates);
894 free(transaction);
895 }
896
897 struct ref_update *ref_transaction_add_update(
898 struct ref_transaction *transaction,
899 const char *refname, unsigned int flags,
900 const struct object_id *new_oid,
901 const struct object_id *old_oid,
902 const char *msg)
903 {
904 struct ref_update *update;
905
906 if (transaction->state != REF_TRANSACTION_OPEN)
907 die("BUG: update called for transaction that is not open");
908
909 FLEX_ALLOC_STR(update, refname, refname);
910 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
911 transaction->updates[transaction->nr++] = update;
912
913 update->flags = flags;
914
915 if (flags & REF_HAVE_NEW)
916 oidcpy(&update->new_oid, new_oid);
917 if (flags & REF_HAVE_OLD)
918 oidcpy(&update->old_oid, old_oid);
919 update->msg = xstrdup_or_null(msg);
920 return update;
921 }
922
923 int ref_transaction_update(struct ref_transaction *transaction,
924 const char *refname,
925 const struct object_id *new_oid,
926 const struct object_id *old_oid,
927 unsigned int flags, const char *msg,
928 struct strbuf *err)
929 {
930 assert(err);
931
932 if ((new_oid && !is_null_oid(new_oid)) ?
933 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
934 !refname_is_safe(refname)) {
935 strbuf_addf(err, "refusing to update ref with bad name '%s'",
936 refname);
937 return -1;
938 }
939
940 if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
941 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
942
943 flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
944
945 ref_transaction_add_update(transaction, refname, flags,
946 new_oid, old_oid, msg);
947 return 0;
948 }
949
950 int ref_transaction_create(struct ref_transaction *transaction,
951 const char *refname,
952 const struct object_id *new_oid,
953 unsigned int flags, const char *msg,
954 struct strbuf *err)
955 {
956 if (!new_oid || is_null_oid(new_oid))
957 die("BUG: create called without valid new_oid");
958 return ref_transaction_update(transaction, refname, new_oid,
959 &null_oid, flags, msg, err);
960 }
961
962 int ref_transaction_delete(struct ref_transaction *transaction,
963 const char *refname,
964 const struct object_id *old_oid,
965 unsigned int flags, const char *msg,
966 struct strbuf *err)
967 {
968 if (old_oid && is_null_oid(old_oid))
969 die("BUG: delete called with old_oid set to zeros");
970 return ref_transaction_update(transaction, refname,
971 &null_oid, old_oid,
972 flags, msg, err);
973 }
974
975 int ref_transaction_verify(struct ref_transaction *transaction,
976 const char *refname,
977 const struct object_id *old_oid,
978 unsigned int flags,
979 struct strbuf *err)
980 {
981 if (!old_oid)
982 die("BUG: verify called with old_oid set to NULL");
983 return ref_transaction_update(transaction, refname,
984 NULL, old_oid,
985 flags, NULL, err);
986 }
987
988 int refs_update_ref(struct ref_store *refs, const char *msg,
989 const char *refname, const struct object_id *new_oid,
990 const struct object_id *old_oid, unsigned int flags,
991 enum action_on_err onerr)
992 {
993 struct ref_transaction *t = NULL;
994 struct strbuf err = STRBUF_INIT;
995 int ret = 0;
996
997 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
998 assert(refs == get_main_ref_store());
999 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1000 } else {
1001 t = ref_store_transaction_begin(refs, &err);
1002 if (!t ||
1003 ref_transaction_update(t, refname, new_oid, old_oid,
1004 flags, msg, &err) ||
1005 ref_transaction_commit(t, &err)) {
1006 ret = 1;
1007 ref_transaction_free(t);
1008 }
1009 }
1010 if (ret) {
1011 const char *str = "update_ref failed for ref '%s': %s";
1012
1013 switch (onerr) {
1014 case UPDATE_REFS_MSG_ON_ERR:
1015 error(str, refname, err.buf);
1016 break;
1017 case UPDATE_REFS_DIE_ON_ERR:
1018 die(str, refname, err.buf);
1019 break;
1020 case UPDATE_REFS_QUIET_ON_ERR:
1021 break;
1022 }
1023 strbuf_release(&err);
1024 return 1;
1025 }
1026 strbuf_release(&err);
1027 if (t)
1028 ref_transaction_free(t);
1029 return 0;
1030 }
1031
1032 int update_ref(const char *msg, const char *refname,
1033 const struct object_id *new_oid,
1034 const struct object_id *old_oid,
1035 unsigned int flags, enum action_on_err onerr)
1036 {
1037 return refs_update_ref(get_main_ref_store(), msg, refname, new_oid,
1038 old_oid, flags, onerr);
1039 }
1040
1041 char *shorten_unambiguous_ref(const char *refname, int strict)
1042 {
1043 int i;
1044 static char **scanf_fmts;
1045 static int nr_rules;
1046 char *short_name;
1047 struct strbuf resolved_buf = STRBUF_INIT;
1048
1049 if (!nr_rules) {
1050 /*
1051 * Pre-generate scanf formats from ref_rev_parse_rules[].
1052 * Generate a format suitable for scanf from a
1053 * ref_rev_parse_rules rule by interpolating "%s" at the
1054 * location of the "%.*s".
1055 */
1056 size_t total_len = 0;
1057 size_t offset = 0;
1058
1059 /* the rule list is NULL terminated, count them first */
1060 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1061 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1062 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1063
1064 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1065
1066 offset = 0;
1067 for (i = 0; i < nr_rules; i++) {
1068 assert(offset < total_len);
1069 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1070 offset += snprintf(scanf_fmts[i], total_len - offset,
1071 ref_rev_parse_rules[i], 2, "%s") + 1;
1072 }
1073 }
1074
1075 /* bail out if there are no rules */
1076 if (!nr_rules)
1077 return xstrdup(refname);
1078
1079 /* buffer for scanf result, at most refname must fit */
1080 short_name = xstrdup(refname);
1081
1082 /* skip first rule, it will always match */
1083 for (i = nr_rules - 1; i > 0 ; --i) {
1084 int j;
1085 int rules_to_fail = i;
1086 int short_name_len;
1087
1088 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1089 continue;
1090
1091 short_name_len = strlen(short_name);
1092
1093 /*
1094 * in strict mode, all (except the matched one) rules
1095 * must fail to resolve to a valid non-ambiguous ref
1096 */
1097 if (strict)
1098 rules_to_fail = nr_rules;
1099
1100 /*
1101 * check if the short name resolves to a valid ref,
1102 * but use only rules prior to the matched one
1103 */
1104 for (j = 0; j < rules_to_fail; j++) {
1105 const char *rule = ref_rev_parse_rules[j];
1106
1107 /* skip matched rule */
1108 if (i == j)
1109 continue;
1110
1111 /*
1112 * the short name is ambiguous, if it resolves
1113 * (with this previous rule) to a valid ref
1114 * read_ref() returns 0 on success
1115 */
1116 strbuf_reset(&resolved_buf);
1117 strbuf_addf(&resolved_buf, rule,
1118 short_name_len, short_name);
1119 if (ref_exists(resolved_buf.buf))
1120 break;
1121 }
1122
1123 /*
1124 * short name is non-ambiguous if all previous rules
1125 * haven't resolved to a valid ref
1126 */
1127 if (j == rules_to_fail) {
1128 strbuf_release(&resolved_buf);
1129 return short_name;
1130 }
1131 }
1132
1133 strbuf_release(&resolved_buf);
1134 free(short_name);
1135 return xstrdup(refname);
1136 }
1137
1138 static struct string_list *hide_refs;
1139
1140 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1141 {
1142 const char *key;
1143 if (!strcmp("transfer.hiderefs", var) ||
1144 (!parse_config_key(var, section, NULL, NULL, &key) &&
1145 !strcmp(key, "hiderefs"))) {
1146 char *ref;
1147 int len;
1148
1149 if (!value)
1150 return config_error_nonbool(var);
1151 ref = xstrdup(value);
1152 len = strlen(ref);
1153 while (len && ref[len - 1] == '/')
1154 ref[--len] = '\0';
1155 if (!hide_refs) {
1156 hide_refs = xcalloc(1, sizeof(*hide_refs));
1157 hide_refs->strdup_strings = 1;
1158 }
1159 string_list_append(hide_refs, ref);
1160 }
1161 return 0;
1162 }
1163
1164 int ref_is_hidden(const char *refname, const char *refname_full)
1165 {
1166 int i;
1167
1168 if (!hide_refs)
1169 return 0;
1170 for (i = hide_refs->nr - 1; i >= 0; i--) {
1171 const char *match = hide_refs->items[i].string;
1172 const char *subject;
1173 int neg = 0;
1174 const char *p;
1175
1176 if (*match == '!') {
1177 neg = 1;
1178 match++;
1179 }
1180
1181 if (*match == '^') {
1182 subject = refname_full;
1183 match++;
1184 } else {
1185 subject = refname;
1186 }
1187
1188 /* refname can be NULL when namespaces are used. */
1189 if (subject &&
1190 skip_prefix(subject, match, &p) &&
1191 (!*p || *p == '/'))
1192 return !neg;
1193 }
1194 return 0;
1195 }
1196
1197 const char *find_descendant_ref(const char *dirname,
1198 const struct string_list *extras,
1199 const struct string_list *skip)
1200 {
1201 int pos;
1202
1203 if (!extras)
1204 return NULL;
1205
1206 /*
1207 * Look at the place where dirname would be inserted into
1208 * extras. If there is an entry at that position that starts
1209 * with dirname (remember, dirname includes the trailing
1210 * slash) and is not in skip, then we have a conflict.
1211 */
1212 for (pos = string_list_find_insert_index(extras, dirname, 0);
1213 pos < extras->nr; pos++) {
1214 const char *extra_refname = extras->items[pos].string;
1215
1216 if (!starts_with(extra_refname, dirname))
1217 break;
1218
1219 if (!skip || !string_list_has_string(skip, extra_refname))
1220 return extra_refname;
1221 }
1222 return NULL;
1223 }
1224
1225 int refs_rename_ref_available(struct ref_store *refs,
1226 const char *old_refname,
1227 const char *new_refname)
1228 {
1229 struct string_list skip = STRING_LIST_INIT_NODUP;
1230 struct strbuf err = STRBUF_INIT;
1231 int ok;
1232
1233 string_list_insert(&skip, old_refname);
1234 ok = !refs_verify_refname_available(refs, new_refname,
1235 NULL, &skip, &err);
1236 if (!ok)
1237 error("%s", err.buf);
1238
1239 string_list_clear(&skip, 0);
1240 strbuf_release(&err);
1241 return ok;
1242 }
1243
1244 int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1245 {
1246 struct object_id oid;
1247 int flag;
1248
1249 if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1250 &oid, &flag))
1251 return fn("HEAD", &oid, flag, cb_data);
1252
1253 return 0;
1254 }
1255
1256 int head_ref(each_ref_fn fn, void *cb_data)
1257 {
1258 return refs_head_ref(get_main_ref_store(), fn, cb_data);
1259 }
1260
1261 struct ref_iterator *refs_ref_iterator_begin(
1262 struct ref_store *refs,
1263 const char *prefix, int trim, int flags)
1264 {
1265 struct ref_iterator *iter;
1266
1267 if (ref_paranoia < 0)
1268 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1269 if (ref_paranoia)
1270 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1271
1272 iter = refs->be->iterator_begin(refs, prefix, flags);
1273
1274 /*
1275 * `iterator_begin()` already takes care of prefix, but we
1276 * might need to do some trimming:
1277 */
1278 if (trim)
1279 iter = prefix_ref_iterator_begin(iter, "", trim);
1280
1281 /* Sanity check for subclasses: */
1282 if (!iter->ordered)
1283 BUG("reference iterator is not ordered");
1284
1285 return iter;
1286 }
1287
1288 /*
1289 * Call fn for each reference in the specified submodule for which the
1290 * refname begins with prefix. If trim is non-zero, then trim that
1291 * many characters off the beginning of each refname before passing
1292 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1293 * include broken references in the iteration. If fn ever returns a
1294 * non-zero value, stop the iteration and return that value;
1295 * otherwise, return 0.
1296 */
1297 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1298 each_ref_fn fn, int trim, int flags, void *cb_data)
1299 {
1300 struct ref_iterator *iter;
1301
1302 if (!refs)
1303 return 0;
1304
1305 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1306
1307 return do_for_each_ref_iterator(iter, fn, cb_data);
1308 }
1309
1310 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1311 {
1312 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1313 }
1314
1315 int for_each_ref(each_ref_fn fn, void *cb_data)
1316 {
1317 return refs_for_each_ref(get_main_ref_store(), fn, cb_data);
1318 }
1319
1320 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1321 each_ref_fn fn, void *cb_data)
1322 {
1323 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1324 }
1325
1326 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1327 {
1328 return refs_for_each_ref_in(get_main_ref_store(), prefix, fn, cb_data);
1329 }
1330
1331 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1332 {
1333 unsigned int flag = 0;
1334
1335 if (broken)
1336 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1337 return do_for_each_ref(get_main_ref_store(),
1338 prefix, fn, 0, flag, cb_data);
1339 }
1340
1341 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1342 each_ref_fn fn, void *cb_data,
1343 unsigned int broken)
1344 {
1345 unsigned int flag = 0;
1346
1347 if (broken)
1348 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1349 return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1350 }
1351
1352 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1353 {
1354 return do_for_each_ref(get_main_ref_store(),
1355 git_replace_ref_base, fn,
1356 strlen(git_replace_ref_base),
1357 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1358 }
1359
1360 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1361 {
1362 struct strbuf buf = STRBUF_INIT;
1363 int ret;
1364 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1365 ret = do_for_each_ref(get_main_ref_store(),
1366 buf.buf, fn, 0, 0, cb_data);
1367 strbuf_release(&buf);
1368 return ret;
1369 }
1370
1371 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1372 {
1373 return do_for_each_ref(refs, "", fn, 0,
1374 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1375 }
1376
1377 int for_each_rawref(each_ref_fn fn, void *cb_data)
1378 {
1379 return refs_for_each_rawref(get_main_ref_store(), fn, cb_data);
1380 }
1381
1382 int refs_read_raw_ref(struct ref_store *ref_store,
1383 const char *refname, struct object_id *oid,
1384 struct strbuf *referent, unsigned int *type)
1385 {
1386 return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1387 }
1388
1389 /* This function needs to return a meaningful errno on failure */
1390 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1391 const char *refname,
1392 int resolve_flags,
1393 struct object_id *oid, int *flags)
1394 {
1395 static struct strbuf sb_refname = STRBUF_INIT;
1396 struct object_id unused_oid;
1397 int unused_flags;
1398 int symref_count;
1399
1400 if (!oid)
1401 oid = &unused_oid;
1402 if (!flags)
1403 flags = &unused_flags;
1404
1405 *flags = 0;
1406
1407 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1408 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1409 !refname_is_safe(refname)) {
1410 errno = EINVAL;
1411 return NULL;
1412 }
1413
1414 /*
1415 * dwim_ref() uses REF_ISBROKEN to distinguish between
1416 * missing refs and refs that were present but invalid,
1417 * to complain about the latter to stderr.
1418 *
1419 * We don't know whether the ref exists, so don't set
1420 * REF_ISBROKEN yet.
1421 */
1422 *flags |= REF_BAD_NAME;
1423 }
1424
1425 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1426 unsigned int read_flags = 0;
1427
1428 if (refs_read_raw_ref(refs, refname,
1429 oid, &sb_refname, &read_flags)) {
1430 *flags |= read_flags;
1431
1432 /* In reading mode, refs must eventually resolve */
1433 if (resolve_flags & RESOLVE_REF_READING)
1434 return NULL;
1435
1436 /*
1437 * Otherwise a missing ref is OK. But the files backend
1438 * may show errors besides ENOENT if there are
1439 * similarly-named refs.
1440 */
1441 if (errno != ENOENT &&
1442 errno != EISDIR &&
1443 errno != ENOTDIR)
1444 return NULL;
1445
1446 oidclr(oid);
1447 if (*flags & REF_BAD_NAME)
1448 *flags |= REF_ISBROKEN;
1449 return refname;
1450 }
1451
1452 *flags |= read_flags;
1453
1454 if (!(read_flags & REF_ISSYMREF)) {
1455 if (*flags & REF_BAD_NAME) {
1456 oidclr(oid);
1457 *flags |= REF_ISBROKEN;
1458 }
1459 return refname;
1460 }
1461
1462 refname = sb_refname.buf;
1463 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1464 oidclr(oid);
1465 return refname;
1466 }
1467 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1468 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1469 !refname_is_safe(refname)) {
1470 errno = EINVAL;
1471 return NULL;
1472 }
1473
1474 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1475 }
1476 }
1477
1478 errno = ELOOP;
1479 return NULL;
1480 }
1481
1482 /* backend functions */
1483 int refs_init_db(struct strbuf *err)
1484 {
1485 struct ref_store *refs = get_main_ref_store();
1486
1487 return refs->be->init_db(refs, err);
1488 }
1489
1490 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1491 struct object_id *oid, int *flags)
1492 {
1493 return refs_resolve_ref_unsafe(get_main_ref_store(), refname,
1494 resolve_flags, oid, flags);
1495 }
1496
1497 int resolve_gitlink_ref(const char *submodule, const char *refname,
1498 struct object_id *oid)
1499 {
1500 struct ref_store *refs;
1501 int flags;
1502
1503 refs = get_submodule_ref_store(submodule);
1504
1505 if (!refs)
1506 return -1;
1507
1508 if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1509 is_null_oid(oid))
1510 return -1;
1511 return 0;
1512 }
1513
1514 struct ref_store_hash_entry
1515 {
1516 struct hashmap_entry ent; /* must be the first member! */
1517
1518 struct ref_store *refs;
1519
1520 /* NUL-terminated identifier of the ref store: */
1521 char name[FLEX_ARRAY];
1522 };
1523
1524 static int ref_store_hash_cmp(const void *unused_cmp_data,
1525 const void *entry, const void *entry_or_key,
1526 const void *keydata)
1527 {
1528 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1529 const char *name = keydata ? keydata : e2->name;
1530
1531 return strcmp(e1->name, name);
1532 }
1533
1534 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1535 const char *name, struct ref_store *refs)
1536 {
1537 struct ref_store_hash_entry *entry;
1538
1539 FLEX_ALLOC_STR(entry, name, name);
1540 hashmap_entry_init(entry, strhash(name));
1541 entry->refs = refs;
1542 return entry;
1543 }
1544
1545 /* A pointer to the ref_store for the main repository: */
1546 static struct ref_store *main_ref_store;
1547
1548 /* A hashmap of ref_stores, stored by submodule name: */
1549 static struct hashmap submodule_ref_stores;
1550
1551 /* A hashmap of ref_stores, stored by worktree id: */
1552 static struct hashmap worktree_ref_stores;
1553
1554 /*
1555 * Look up a ref store by name. If that ref_store hasn't been
1556 * registered yet, return NULL.
1557 */
1558 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1559 const char *name)
1560 {
1561 struct ref_store_hash_entry *entry;
1562
1563 if (!map->tablesize)
1564 /* It's initialized on demand in register_ref_store(). */
1565 return NULL;
1566
1567 entry = hashmap_get_from_hash(map, strhash(name), name);
1568 return entry ? entry->refs : NULL;
1569 }
1570
1571 /*
1572 * Create, record, and return a ref_store instance for the specified
1573 * gitdir.
1574 */
1575 static struct ref_store *ref_store_init(const char *gitdir,
1576 unsigned int flags)
1577 {
1578 const char *be_name = "files";
1579 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1580 struct ref_store *refs;
1581
1582 if (!be)
1583 die("BUG: reference backend %s is unknown", be_name);
1584
1585 refs = be->init(gitdir, flags);
1586 return refs;
1587 }
1588
1589 struct ref_store *get_main_ref_store(void)
1590 {
1591 if (main_ref_store)
1592 return main_ref_store;
1593
1594 main_ref_store = ref_store_init(get_git_dir(), REF_STORE_ALL_CAPS);
1595 return main_ref_store;
1596 }
1597
1598 /*
1599 * Associate a ref store with a name. It is a fatal error to call this
1600 * function twice for the same name.
1601 */
1602 static void register_ref_store_map(struct hashmap *map,
1603 const char *type,
1604 struct ref_store *refs,
1605 const char *name)
1606 {
1607 if (!map->tablesize)
1608 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1609
1610 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1611 die("BUG: %s ref_store '%s' initialized twice", type, name);
1612 }
1613
1614 struct ref_store *get_submodule_ref_store(const char *submodule)
1615 {
1616 struct strbuf submodule_sb = STRBUF_INIT;
1617 struct ref_store *refs;
1618 char *to_free = NULL;
1619 size_t len;
1620
1621 if (!submodule)
1622 return NULL;
1623
1624 len = strlen(submodule);
1625 while (len && is_dir_sep(submodule[len - 1]))
1626 len--;
1627 if (!len)
1628 return NULL;
1629
1630 if (submodule[len])
1631 /* We need to strip off one or more trailing slashes */
1632 submodule = to_free = xmemdupz(submodule, len);
1633
1634 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1635 if (refs)
1636 goto done;
1637
1638 strbuf_addstr(&submodule_sb, submodule);
1639 if (!is_nonbare_repository_dir(&submodule_sb))
1640 goto done;
1641
1642 if (submodule_to_gitdir(&submodule_sb, submodule))
1643 goto done;
1644
1645 /* assume that add_submodule_odb() has been called */
1646 refs = ref_store_init(submodule_sb.buf,
1647 REF_STORE_READ | REF_STORE_ODB);
1648 register_ref_store_map(&submodule_ref_stores, "submodule",
1649 refs, submodule);
1650
1651 done:
1652 strbuf_release(&submodule_sb);
1653 free(to_free);
1654
1655 return refs;
1656 }
1657
1658 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1659 {
1660 struct ref_store *refs;
1661 const char *id;
1662
1663 if (wt->is_current)
1664 return get_main_ref_store();
1665
1666 id = wt->id ? wt->id : "/";
1667 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1668 if (refs)
1669 return refs;
1670
1671 if (wt->id)
1672 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1673 REF_STORE_ALL_CAPS);
1674 else
1675 refs = ref_store_init(get_git_common_dir(),
1676 REF_STORE_ALL_CAPS);
1677
1678 if (refs)
1679 register_ref_store_map(&worktree_ref_stores, "worktree",
1680 refs, id);
1681 return refs;
1682 }
1683
1684 void base_ref_store_init(struct ref_store *refs,
1685 const struct ref_storage_be *be)
1686 {
1687 refs->be = be;
1688 }
1689
1690 /* backend functions */
1691 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1692 {
1693 return refs->be->pack_refs(refs, flags);
1694 }
1695
1696 int refs_peel_ref(struct ref_store *refs, const char *refname,
1697 struct object_id *oid)
1698 {
1699 int flag;
1700 struct object_id base;
1701
1702 if (current_ref_iter && current_ref_iter->refname == refname) {
1703 struct object_id peeled;
1704
1705 if (ref_iterator_peel(current_ref_iter, &peeled))
1706 return -1;
1707 oidcpy(oid, &peeled);
1708 return 0;
1709 }
1710
1711 if (refs_read_ref_full(refs, refname,
1712 RESOLVE_REF_READING, &base, &flag))
1713 return -1;
1714
1715 return peel_object(&base, oid);
1716 }
1717
1718 int peel_ref(const char *refname, struct object_id *oid)
1719 {
1720 return refs_peel_ref(get_main_ref_store(), refname, oid);
1721 }
1722
1723 int refs_create_symref(struct ref_store *refs,
1724 const char *ref_target,
1725 const char *refs_heads_master,
1726 const char *logmsg)
1727 {
1728 return refs->be->create_symref(refs, ref_target,
1729 refs_heads_master,
1730 logmsg);
1731 }
1732
1733 int create_symref(const char *ref_target, const char *refs_heads_master,
1734 const char *logmsg)
1735 {
1736 return refs_create_symref(get_main_ref_store(), ref_target,
1737 refs_heads_master, logmsg);
1738 }
1739
1740 int ref_update_reject_duplicates(struct string_list *refnames,
1741 struct strbuf *err)
1742 {
1743 size_t i, n = refnames->nr;
1744
1745 assert(err);
1746
1747 for (i = 1; i < n; i++) {
1748 int cmp = strcmp(refnames->items[i - 1].string,
1749 refnames->items[i].string);
1750
1751 if (!cmp) {
1752 strbuf_addf(err,
1753 "multiple updates for ref '%s' not allowed.",
1754 refnames->items[i].string);
1755 return 1;
1756 } else if (cmp > 0) {
1757 die("BUG: ref_update_reject_duplicates() received unsorted list");
1758 }
1759 }
1760 return 0;
1761 }
1762
1763 int ref_transaction_prepare(struct ref_transaction *transaction,
1764 struct strbuf *err)
1765 {
1766 struct ref_store *refs = transaction->ref_store;
1767
1768 switch (transaction->state) {
1769 case REF_TRANSACTION_OPEN:
1770 /* Good. */
1771 break;
1772 case REF_TRANSACTION_PREPARED:
1773 die("BUG: prepare called twice on reference transaction");
1774 break;
1775 case REF_TRANSACTION_CLOSED:
1776 die("BUG: prepare called on a closed reference transaction");
1777 break;
1778 default:
1779 die("BUG: unexpected reference transaction state");
1780 break;
1781 }
1782
1783 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1784 strbuf_addstr(err,
1785 _("ref updates forbidden inside quarantine environment"));
1786 return -1;
1787 }
1788
1789 return refs->be->transaction_prepare(refs, transaction, err);
1790 }
1791
1792 int ref_transaction_abort(struct ref_transaction *transaction,
1793 struct strbuf *err)
1794 {
1795 struct ref_store *refs = transaction->ref_store;
1796 int ret = 0;
1797
1798 switch (transaction->state) {
1799 case REF_TRANSACTION_OPEN:
1800 /* No need to abort explicitly. */
1801 break;
1802 case REF_TRANSACTION_PREPARED:
1803 ret = refs->be->transaction_abort(refs, transaction, err);
1804 break;
1805 case REF_TRANSACTION_CLOSED:
1806 die("BUG: abort called on a closed reference transaction");
1807 break;
1808 default:
1809 die("BUG: unexpected reference transaction state");
1810 break;
1811 }
1812
1813 ref_transaction_free(transaction);
1814 return ret;
1815 }
1816
1817 int ref_transaction_commit(struct ref_transaction *transaction,
1818 struct strbuf *err)
1819 {
1820 struct ref_store *refs = transaction->ref_store;
1821 int ret;
1822
1823 switch (transaction->state) {
1824 case REF_TRANSACTION_OPEN:
1825 /* Need to prepare first. */
1826 ret = ref_transaction_prepare(transaction, err);
1827 if (ret)
1828 return ret;
1829 break;
1830 case REF_TRANSACTION_PREPARED:
1831 /* Fall through to finish. */
1832 break;
1833 case REF_TRANSACTION_CLOSED:
1834 die("BUG: commit called on a closed reference transaction");
1835 break;
1836 default:
1837 die("BUG: unexpected reference transaction state");
1838 break;
1839 }
1840
1841 return refs->be->transaction_finish(refs, transaction, err);
1842 }
1843
1844 int refs_verify_refname_available(struct ref_store *refs,
1845 const char *refname,
1846 const struct string_list *extras,
1847 const struct string_list *skip,
1848 struct strbuf *err)
1849 {
1850 const char *slash;
1851 const char *extra_refname;
1852 struct strbuf dirname = STRBUF_INIT;
1853 struct strbuf referent = STRBUF_INIT;
1854 struct object_id oid;
1855 unsigned int type;
1856 struct ref_iterator *iter;
1857 int ok;
1858 int ret = -1;
1859
1860 /*
1861 * For the sake of comments in this function, suppose that
1862 * refname is "refs/foo/bar".
1863 */
1864
1865 assert(err);
1866
1867 strbuf_grow(&dirname, strlen(refname) + 1);
1868 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1869 /* Expand dirname to the new prefix, not including the trailing slash: */
1870 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1871
1872 /*
1873 * We are still at a leading dir of the refname (e.g.,
1874 * "refs/foo"; if there is a reference with that name,
1875 * it is a conflict, *unless* it is in skip.
1876 */
1877 if (skip && string_list_has_string(skip, dirname.buf))
1878 continue;
1879
1880 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
1881 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1882 dirname.buf, refname);
1883 goto cleanup;
1884 }
1885
1886 if (extras && string_list_has_string(extras, dirname.buf)) {
1887 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1888 refname, dirname.buf);
1889 goto cleanup;
1890 }
1891 }
1892
1893 /*
1894 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1895 * There is no point in searching for a reference with that
1896 * name, because a refname isn't considered to conflict with
1897 * itself. But we still need to check for references whose
1898 * names are in the "refs/foo/bar/" namespace, because they
1899 * *do* conflict.
1900 */
1901 strbuf_addstr(&dirname, refname + dirname.len);
1902 strbuf_addch(&dirname, '/');
1903
1904 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
1905 DO_FOR_EACH_INCLUDE_BROKEN);
1906 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
1907 if (skip &&
1908 string_list_has_string(skip, iter->refname))
1909 continue;
1910
1911 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1912 iter->refname, refname);
1913 ref_iterator_abort(iter);
1914 goto cleanup;
1915 }
1916
1917 if (ok != ITER_DONE)
1918 die("BUG: error while iterating over references");
1919
1920 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
1921 if (extra_refname)
1922 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1923 refname, extra_refname);
1924 else
1925 ret = 0;
1926
1927 cleanup:
1928 strbuf_release(&referent);
1929 strbuf_release(&dirname);
1930 return ret;
1931 }
1932
1933 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1934 {
1935 struct ref_iterator *iter;
1936
1937 iter = refs->be->reflog_iterator_begin(refs);
1938
1939 return do_for_each_ref_iterator(iter, fn, cb_data);
1940 }
1941
1942 int for_each_reflog(each_ref_fn fn, void *cb_data)
1943 {
1944 return refs_for_each_reflog(get_main_ref_store(), fn, cb_data);
1945 }
1946
1947 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
1948 const char *refname,
1949 each_reflog_ent_fn fn,
1950 void *cb_data)
1951 {
1952 return refs->be->for_each_reflog_ent_reverse(refs, refname,
1953 fn, cb_data);
1954 }
1955
1956 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
1957 void *cb_data)
1958 {
1959 return refs_for_each_reflog_ent_reverse(get_main_ref_store(),
1960 refname, fn, cb_data);
1961 }
1962
1963 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
1964 each_reflog_ent_fn fn, void *cb_data)
1965 {
1966 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
1967 }
1968
1969 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
1970 void *cb_data)
1971 {
1972 return refs_for_each_reflog_ent(get_main_ref_store(), refname,
1973 fn, cb_data);
1974 }
1975
1976 int refs_reflog_exists(struct ref_store *refs, const char *refname)
1977 {
1978 return refs->be->reflog_exists(refs, refname);
1979 }
1980
1981 int reflog_exists(const char *refname)
1982 {
1983 return refs_reflog_exists(get_main_ref_store(), refname);
1984 }
1985
1986 int refs_create_reflog(struct ref_store *refs, const char *refname,
1987 int force_create, struct strbuf *err)
1988 {
1989 return refs->be->create_reflog(refs, refname, force_create, err);
1990 }
1991
1992 int safe_create_reflog(const char *refname, int force_create,
1993 struct strbuf *err)
1994 {
1995 return refs_create_reflog(get_main_ref_store(), refname,
1996 force_create, err);
1997 }
1998
1999 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2000 {
2001 return refs->be->delete_reflog(refs, refname);
2002 }
2003
2004 int delete_reflog(const char *refname)
2005 {
2006 return refs_delete_reflog(get_main_ref_store(), refname);
2007 }
2008
2009 int refs_reflog_expire(struct ref_store *refs,
2010 const char *refname, const struct object_id *oid,
2011 unsigned int flags,
2012 reflog_expiry_prepare_fn prepare_fn,
2013 reflog_expiry_should_prune_fn should_prune_fn,
2014 reflog_expiry_cleanup_fn cleanup_fn,
2015 void *policy_cb_data)
2016 {
2017 return refs->be->reflog_expire(refs, refname, oid, flags,
2018 prepare_fn, should_prune_fn,
2019 cleanup_fn, policy_cb_data);
2020 }
2021
2022 int reflog_expire(const char *refname, const struct object_id *oid,
2023 unsigned int flags,
2024 reflog_expiry_prepare_fn prepare_fn,
2025 reflog_expiry_should_prune_fn should_prune_fn,
2026 reflog_expiry_cleanup_fn cleanup_fn,
2027 void *policy_cb_data)
2028 {
2029 return refs_reflog_expire(get_main_ref_store(),
2030 refname, oid, flags,
2031 prepare_fn, should_prune_fn,
2032 cleanup_fn, policy_cb_data);
2033 }
2034
2035 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2036 struct strbuf *err)
2037 {
2038 struct ref_store *refs = transaction->ref_store;
2039
2040 return refs->be->initial_transaction_commit(refs, transaction, err);
2041 }
2042
2043 int refs_delete_refs(struct ref_store *refs, const char *msg,
2044 struct string_list *refnames, unsigned int flags)
2045 {
2046 return refs->be->delete_refs(refs, msg, refnames, flags);
2047 }
2048
2049 int delete_refs(const char *msg, struct string_list *refnames,
2050 unsigned int flags)
2051 {
2052 return refs_delete_refs(get_main_ref_store(), msg, refnames, flags);
2053 }
2054
2055 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2056 const char *newref, const char *logmsg)
2057 {
2058 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2059 }
2060
2061 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2062 {
2063 return refs_rename_ref(get_main_ref_store(), oldref, newref, logmsg);
2064 }
2065
2066 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2067 const char *newref, const char *logmsg)
2068 {
2069 return refs->be->copy_ref(refs, oldref, newref, logmsg);
2070 }
2071
2072 int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2073 {
2074 return refs_copy_existing_ref(get_main_ref_store(), oldref, newref, logmsg);
2075 }