Merge branch 'js/gitweb-raw-blob-link-in-history'
[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 unsigned char *sha1, int *flags)
198 {
199 const char *result;
200
201 result = refs_resolve_ref_unsafe(refs, refname, resolve_flags,
202 sha1, flags);
203 return xstrdup_or_null(result);
204 }
205
206 char *resolve_refdup(const char *refname, int resolve_flags,
207 unsigned char *sha1, int *flags)
208 {
209 return refs_resolve_refdup(get_main_ref_store(),
210 refname, resolve_flags,
211 sha1, 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, unsigned char *sha1, int *flags)
223 {
224 if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, sha1, flags))
225 return 0;
226 return -1;
227 }
228
229 int read_ref_full(const char *refname, int resolve_flags, unsigned char *sha1, int *flags)
230 {
231 return refs_read_ref_full(get_main_ref_store(), refname,
232 resolve_flags, sha1, flags);
233 }
234
235 int read_ref(const char *refname, unsigned char *sha1)
236 {
237 return read_ref_full(refname, RESOLVE_REF_READING, sha1, NULL);
238 }
239
240 int ref_exists(const char *refname)
241 {
242 unsigned char sha1[20];
243 return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, sha1, NULL);
244 }
245
246 static int filter_refs(const char *refname, const struct object_id *oid,
247 int flags, void *data)
248 {
249 struct ref_filter *filter = (struct ref_filter *)data;
250
251 if (wildmatch(filter->pattern, refname, 0))
252 return 0;
253 return filter->fn(refname, oid, flags, filter->cb_data);
254 }
255
256 enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
257 {
258 struct object *o = lookup_unknown_object(name);
259
260 if (o->type == OBJ_NONE) {
261 int type = sha1_object_info(name, NULL);
262 if (type < 0 || !object_as_type(o, type, 0))
263 return PEEL_INVALID;
264 }
265
266 if (o->type != OBJ_TAG)
267 return PEEL_NON_TAG;
268
269 o = deref_tag_noverify(o);
270 if (!o)
271 return PEEL_INVALID;
272
273 hashcpy(sha1, o->oid.hash);
274 return PEEL_PEELED;
275 }
276
277 struct warn_if_dangling_data {
278 FILE *fp;
279 const char *refname;
280 const struct string_list *refnames;
281 const char *msg_fmt;
282 };
283
284 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
285 int flags, void *cb_data)
286 {
287 struct warn_if_dangling_data *d = cb_data;
288 const char *resolves_to;
289 struct object_id junk;
290
291 if (!(flags & REF_ISSYMREF))
292 return 0;
293
294 resolves_to = resolve_ref_unsafe(refname, 0, junk.hash, NULL);
295 if (!resolves_to
296 || (d->refname
297 ? strcmp(resolves_to, d->refname)
298 : !string_list_has_string(d->refnames, resolves_to))) {
299 return 0;
300 }
301
302 fprintf(d->fp, d->msg_fmt, refname);
303 fputc('\n', d->fp);
304 return 0;
305 }
306
307 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
308 {
309 struct warn_if_dangling_data data;
310
311 data.fp = fp;
312 data.refname = refname;
313 data.refnames = NULL;
314 data.msg_fmt = msg_fmt;
315 for_each_rawref(warn_if_dangling_symref, &data);
316 }
317
318 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
319 {
320 struct warn_if_dangling_data data;
321
322 data.fp = fp;
323 data.refname = NULL;
324 data.refnames = refnames;
325 data.msg_fmt = msg_fmt;
326 for_each_rawref(warn_if_dangling_symref, &data);
327 }
328
329 int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
330 {
331 return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
332 }
333
334 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
335 {
336 return refs_for_each_tag_ref(get_main_ref_store(), fn, cb_data);
337 }
338
339 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
340 {
341 return refs_for_each_tag_ref(get_submodule_ref_store(submodule),
342 fn, cb_data);
343 }
344
345 int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
346 {
347 return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
348 }
349
350 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
351 {
352 return refs_for_each_branch_ref(get_main_ref_store(), fn, cb_data);
353 }
354
355 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
356 {
357 return refs_for_each_branch_ref(get_submodule_ref_store(submodule),
358 fn, cb_data);
359 }
360
361 int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
362 {
363 return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
364 }
365
366 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
367 {
368 return refs_for_each_remote_ref(get_main_ref_store(), fn, cb_data);
369 }
370
371 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
372 {
373 return refs_for_each_remote_ref(get_submodule_ref_store(submodule),
374 fn, cb_data);
375 }
376
377 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
378 {
379 struct strbuf buf = STRBUF_INIT;
380 int ret = 0;
381 struct object_id oid;
382 int flag;
383
384 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
385 if (!read_ref_full(buf.buf, RESOLVE_REF_READING, oid.hash, &flag))
386 ret = fn(buf.buf, &oid, flag, cb_data);
387 strbuf_release(&buf);
388
389 return ret;
390 }
391
392 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
393 const char *prefix, void *cb_data)
394 {
395 struct strbuf real_pattern = STRBUF_INIT;
396 struct ref_filter filter;
397 int ret;
398
399 if (!prefix && !starts_with(pattern, "refs/"))
400 strbuf_addstr(&real_pattern, "refs/");
401 else if (prefix)
402 strbuf_addstr(&real_pattern, prefix);
403 strbuf_addstr(&real_pattern, pattern);
404
405 if (!has_glob_specials(pattern)) {
406 /* Append implied '/' '*' if not present. */
407 strbuf_complete(&real_pattern, '/');
408 /* No need to check for '*', there is none. */
409 strbuf_addch(&real_pattern, '*');
410 }
411
412 filter.pattern = real_pattern.buf;
413 filter.fn = fn;
414 filter.cb_data = cb_data;
415 ret = for_each_ref(filter_refs, &filter);
416
417 strbuf_release(&real_pattern);
418 return ret;
419 }
420
421 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
422 {
423 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
424 }
425
426 const char *prettify_refname(const char *name)
427 {
428 if (skip_prefix(name, "refs/heads/", &name) ||
429 skip_prefix(name, "refs/tags/", &name) ||
430 skip_prefix(name, "refs/remotes/", &name))
431 ; /* nothing */
432 return name;
433 }
434
435 static const char *ref_rev_parse_rules[] = {
436 "%.*s",
437 "refs/%.*s",
438 "refs/tags/%.*s",
439 "refs/heads/%.*s",
440 "refs/remotes/%.*s",
441 "refs/remotes/%.*s/HEAD",
442 NULL
443 };
444
445 int refname_match(const char *abbrev_name, const char *full_name)
446 {
447 const char **p;
448 const int abbrev_name_len = strlen(abbrev_name);
449
450 for (p = ref_rev_parse_rules; *p; p++) {
451 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
452 return 1;
453 }
454 }
455
456 return 0;
457 }
458
459 /*
460 * *string and *len will only be substituted, and *string returned (for
461 * later free()ing) if the string passed in is a magic short-hand form
462 * to name a branch.
463 */
464 static char *substitute_branch_name(const char **string, int *len)
465 {
466 struct strbuf buf = STRBUF_INIT;
467 int ret = interpret_branch_name(*string, *len, &buf, 0);
468
469 if (ret == *len) {
470 size_t size;
471 *string = strbuf_detach(&buf, &size);
472 *len = size;
473 return (char *)*string;
474 }
475
476 return NULL;
477 }
478
479 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
480 {
481 char *last_branch = substitute_branch_name(&str, &len);
482 int refs_found = expand_ref(str, len, sha1, ref);
483 free(last_branch);
484 return refs_found;
485 }
486
487 int expand_ref(const char *str, int len, unsigned char *sha1, char **ref)
488 {
489 const char **p, *r;
490 int refs_found = 0;
491 struct strbuf fullref = STRBUF_INIT;
492
493 *ref = NULL;
494 for (p = ref_rev_parse_rules; *p; p++) {
495 unsigned char sha1_from_ref[20];
496 unsigned char *this_result;
497 int flag;
498
499 this_result = refs_found ? sha1_from_ref : sha1;
500 strbuf_reset(&fullref);
501 strbuf_addf(&fullref, *p, len, str);
502 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
503 this_result, &flag);
504 if (r) {
505 if (!refs_found++)
506 *ref = xstrdup(r);
507 if (!warn_ambiguous_refs)
508 break;
509 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
510 warning("ignoring dangling symref %s.", fullref.buf);
511 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
512 warning("ignoring broken ref %s.", fullref.buf);
513 }
514 }
515 strbuf_release(&fullref);
516 return refs_found;
517 }
518
519 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
520 {
521 char *last_branch = substitute_branch_name(&str, &len);
522 const char **p;
523 int logs_found = 0;
524 struct strbuf path = STRBUF_INIT;
525
526 *log = NULL;
527 for (p = ref_rev_parse_rules; *p; p++) {
528 unsigned char hash[20];
529 const char *ref, *it;
530
531 strbuf_reset(&path);
532 strbuf_addf(&path, *p, len, str);
533 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
534 hash, NULL);
535 if (!ref)
536 continue;
537 if (reflog_exists(path.buf))
538 it = path.buf;
539 else if (strcmp(ref, path.buf) && reflog_exists(ref))
540 it = ref;
541 else
542 continue;
543 if (!logs_found++) {
544 *log = xstrdup(it);
545 hashcpy(sha1, hash);
546 }
547 if (!warn_ambiguous_refs)
548 break;
549 }
550 strbuf_release(&path);
551 free(last_branch);
552 return logs_found;
553 }
554
555 static int is_per_worktree_ref(const char *refname)
556 {
557 return !strcmp(refname, "HEAD") ||
558 starts_with(refname, "refs/bisect/");
559 }
560
561 static int is_pseudoref_syntax(const char *refname)
562 {
563 const char *c;
564
565 for (c = refname; *c; c++) {
566 if (!isupper(*c) && *c != '-' && *c != '_')
567 return 0;
568 }
569
570 return 1;
571 }
572
573 enum ref_type ref_type(const char *refname)
574 {
575 if (is_per_worktree_ref(refname))
576 return REF_TYPE_PER_WORKTREE;
577 if (is_pseudoref_syntax(refname))
578 return REF_TYPE_PSEUDOREF;
579 return REF_TYPE_NORMAL;
580 }
581
582 static int write_pseudoref(const char *pseudoref, const unsigned char *sha1,
583 const unsigned char *old_sha1, struct strbuf *err)
584 {
585 const char *filename;
586 int fd;
587 static struct lock_file lock;
588 struct strbuf buf = STRBUF_INIT;
589 int ret = -1;
590
591 strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
592
593 filename = git_path("%s", pseudoref);
594 fd = hold_lock_file_for_update(&lock, filename, LOCK_DIE_ON_ERROR);
595 if (fd < 0) {
596 strbuf_addf(err, "could not open '%s' for writing: %s",
597 filename, strerror(errno));
598 return -1;
599 }
600
601 if (old_sha1) {
602 unsigned char actual_old_sha1[20];
603
604 if (read_ref(pseudoref, actual_old_sha1))
605 die("could not read ref '%s'", pseudoref);
606 if (hashcmp(actual_old_sha1, old_sha1)) {
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) != buf.len) {
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 unsigned char *old_sha1)
627 {
628 static struct lock_file lock;
629 const char *filename;
630
631 filename = git_path("%s", pseudoref);
632
633 if (old_sha1 && !is_null_sha1(old_sha1)) {
634 int fd;
635 unsigned char actual_old_sha1[20];
636
637 fd = hold_lock_file_for_update(&lock, filename,
638 LOCK_DIE_ON_ERROR);
639 if (fd < 0)
640 die_errno(_("Could not open '%s' for writing"), filename);
641 if (read_ref(pseudoref, actual_old_sha1))
642 die("could not read ref '%s'", pseudoref);
643 if (hashcmp(actual_old_sha1, old_sha1)) {
644 warning("Unexpected sha1 when deleting %s", pseudoref);
645 rollback_lock_file(&lock);
646 return -1;
647 }
648
649 unlink(filename);
650 rollback_lock_file(&lock);
651 } else {
652 unlink(filename);
653 }
654
655 return 0;
656 }
657
658 int refs_delete_ref(struct ref_store *refs, const char *msg,
659 const char *refname,
660 const unsigned char *old_sha1,
661 unsigned int flags)
662 {
663 struct ref_transaction *transaction;
664 struct strbuf err = STRBUF_INIT;
665
666 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
667 assert(refs == get_main_ref_store());
668 return delete_pseudoref(refname, old_sha1);
669 }
670
671 transaction = ref_store_transaction_begin(refs, &err);
672 if (!transaction ||
673 ref_transaction_delete(transaction, refname, old_sha1,
674 flags, msg, &err) ||
675 ref_transaction_commit(transaction, &err)) {
676 error("%s", err.buf);
677 ref_transaction_free(transaction);
678 strbuf_release(&err);
679 return 1;
680 }
681 ref_transaction_free(transaction);
682 strbuf_release(&err);
683 return 0;
684 }
685
686 int delete_ref(const char *msg, const char *refname,
687 const unsigned char *old_sha1, unsigned int flags)
688 {
689 return refs_delete_ref(get_main_ref_store(), msg, refname,
690 old_sha1, flags);
691 }
692
693 int copy_reflog_msg(char *buf, const char *msg)
694 {
695 char *cp = buf;
696 char c;
697 int wasspace = 1;
698
699 *cp++ = '\t';
700 while ((c = *msg++)) {
701 if (wasspace && isspace(c))
702 continue;
703 wasspace = isspace(c);
704 if (wasspace)
705 c = ' ';
706 *cp++ = c;
707 }
708 while (buf < cp && isspace(cp[-1]))
709 cp--;
710 *cp++ = '\n';
711 return cp - buf;
712 }
713
714 int should_autocreate_reflog(const char *refname)
715 {
716 switch (log_all_ref_updates) {
717 case LOG_REFS_ALWAYS:
718 return 1;
719 case LOG_REFS_NORMAL:
720 return starts_with(refname, "refs/heads/") ||
721 starts_with(refname, "refs/remotes/") ||
722 starts_with(refname, "refs/notes/") ||
723 !strcmp(refname, "HEAD");
724 default:
725 return 0;
726 }
727 }
728
729 int is_branch(const char *refname)
730 {
731 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
732 }
733
734 struct read_ref_at_cb {
735 const char *refname;
736 timestamp_t at_time;
737 int cnt;
738 int reccnt;
739 unsigned char *sha1;
740 int found_it;
741
742 unsigned char osha1[20];
743 unsigned char nsha1[20];
744 int tz;
745 timestamp_t date;
746 char **msg;
747 timestamp_t *cutoff_time;
748 int *cutoff_tz;
749 int *cutoff_cnt;
750 };
751
752 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
753 const char *email, timestamp_t timestamp, int tz,
754 const char *message, void *cb_data)
755 {
756 struct read_ref_at_cb *cb = cb_data;
757
758 cb->reccnt++;
759 cb->tz = tz;
760 cb->date = timestamp;
761
762 if (timestamp <= cb->at_time || cb->cnt == 0) {
763 if (cb->msg)
764 *cb->msg = xstrdup(message);
765 if (cb->cutoff_time)
766 *cb->cutoff_time = timestamp;
767 if (cb->cutoff_tz)
768 *cb->cutoff_tz = tz;
769 if (cb->cutoff_cnt)
770 *cb->cutoff_cnt = cb->reccnt - 1;
771 /*
772 * we have not yet updated cb->[n|o]sha1 so they still
773 * hold the values for the previous record.
774 */
775 if (!is_null_sha1(cb->osha1)) {
776 hashcpy(cb->sha1, noid->hash);
777 if (hashcmp(cb->osha1, noid->hash))
778 warning("Log for ref %s has gap after %s.",
779 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
780 }
781 else if (cb->date == cb->at_time)
782 hashcpy(cb->sha1, noid->hash);
783 else if (hashcmp(noid->hash, cb->sha1))
784 warning("Log for ref %s unexpectedly ended on %s.",
785 cb->refname, show_date(cb->date, cb->tz,
786 DATE_MODE(RFC2822)));
787 hashcpy(cb->osha1, ooid->hash);
788 hashcpy(cb->nsha1, noid->hash);
789 cb->found_it = 1;
790 return 1;
791 }
792 hashcpy(cb->osha1, ooid->hash);
793 hashcpy(cb->nsha1, noid->hash);
794 if (cb->cnt > 0)
795 cb->cnt--;
796 return 0;
797 }
798
799 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
800 const char *email, timestamp_t timestamp,
801 int tz, const char *message, void *cb_data)
802 {
803 struct read_ref_at_cb *cb = cb_data;
804
805 if (cb->msg)
806 *cb->msg = xstrdup(message);
807 if (cb->cutoff_time)
808 *cb->cutoff_time = timestamp;
809 if (cb->cutoff_tz)
810 *cb->cutoff_tz = tz;
811 if (cb->cutoff_cnt)
812 *cb->cutoff_cnt = cb->reccnt;
813 hashcpy(cb->sha1, ooid->hash);
814 if (is_null_sha1(cb->sha1))
815 hashcpy(cb->sha1, noid->hash);
816 /* We just want the first entry */
817 return 1;
818 }
819
820 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
821 unsigned char *sha1, char **msg,
822 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
823 {
824 struct read_ref_at_cb cb;
825
826 memset(&cb, 0, sizeof(cb));
827 cb.refname = refname;
828 cb.at_time = at_time;
829 cb.cnt = cnt;
830 cb.msg = msg;
831 cb.cutoff_time = cutoff_time;
832 cb.cutoff_tz = cutoff_tz;
833 cb.cutoff_cnt = cutoff_cnt;
834 cb.sha1 = sha1;
835
836 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
837
838 if (!cb.reccnt) {
839 if (flags & GET_OID_QUIETLY)
840 exit(128);
841 else
842 die("Log for %s is empty.", refname);
843 }
844 if (cb.found_it)
845 return 0;
846
847 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
848
849 return 1;
850 }
851
852 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
853 struct strbuf *err)
854 {
855 struct ref_transaction *tr;
856 assert(err);
857
858 tr = xcalloc(1, sizeof(struct ref_transaction));
859 tr->ref_store = refs;
860 return tr;
861 }
862
863 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
864 {
865 return ref_store_transaction_begin(get_main_ref_store(), err);
866 }
867
868 void ref_transaction_free(struct ref_transaction *transaction)
869 {
870 size_t i;
871
872 if (!transaction)
873 return;
874
875 switch (transaction->state) {
876 case REF_TRANSACTION_OPEN:
877 case REF_TRANSACTION_CLOSED:
878 /* OK */
879 break;
880 case REF_TRANSACTION_PREPARED:
881 die("BUG: free called on a prepared reference transaction");
882 break;
883 default:
884 die("BUG: unexpected reference transaction state");
885 break;
886 }
887
888 for (i = 0; i < transaction->nr; i++) {
889 free(transaction->updates[i]->msg);
890 free(transaction->updates[i]);
891 }
892 free(transaction->updates);
893 free(transaction);
894 }
895
896 struct ref_update *ref_transaction_add_update(
897 struct ref_transaction *transaction,
898 const char *refname, unsigned int flags,
899 const unsigned char *new_sha1,
900 const unsigned char *old_sha1,
901 const char *msg)
902 {
903 struct ref_update *update;
904
905 if (transaction->state != REF_TRANSACTION_OPEN)
906 die("BUG: update called for transaction that is not open");
907
908 if ((flags & REF_ISPRUNING) && !(flags & REF_NODEREF))
909 die("BUG: REF_ISPRUNING set without REF_NODEREF");
910
911 FLEX_ALLOC_STR(update, refname, refname);
912 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
913 transaction->updates[transaction->nr++] = update;
914
915 update->flags = flags;
916
917 if (flags & REF_HAVE_NEW)
918 hashcpy(update->new_oid.hash, new_sha1);
919 if (flags & REF_HAVE_OLD)
920 hashcpy(update->old_oid.hash, old_sha1);
921 update->msg = xstrdup_or_null(msg);
922 return update;
923 }
924
925 int ref_transaction_update(struct ref_transaction *transaction,
926 const char *refname,
927 const unsigned char *new_sha1,
928 const unsigned char *old_sha1,
929 unsigned int flags, const char *msg,
930 struct strbuf *err)
931 {
932 assert(err);
933
934 if ((new_sha1 && !is_null_sha1(new_sha1)) ?
935 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
936 !refname_is_safe(refname)) {
937 strbuf_addf(err, "refusing to update ref with bad name '%s'",
938 refname);
939 return -1;
940 }
941
942 flags |= (new_sha1 ? REF_HAVE_NEW : 0) | (old_sha1 ? REF_HAVE_OLD : 0);
943
944 ref_transaction_add_update(transaction, refname, flags,
945 new_sha1, old_sha1, msg);
946 return 0;
947 }
948
949 int ref_transaction_create(struct ref_transaction *transaction,
950 const char *refname,
951 const unsigned char *new_sha1,
952 unsigned int flags, const char *msg,
953 struct strbuf *err)
954 {
955 if (!new_sha1 || is_null_sha1(new_sha1))
956 die("BUG: create called without valid new_sha1");
957 return ref_transaction_update(transaction, refname, new_sha1,
958 null_sha1, flags, msg, err);
959 }
960
961 int ref_transaction_delete(struct ref_transaction *transaction,
962 const char *refname,
963 const unsigned char *old_sha1,
964 unsigned int flags, const char *msg,
965 struct strbuf *err)
966 {
967 if (old_sha1 && is_null_sha1(old_sha1))
968 die("BUG: delete called with old_sha1 set to zeros");
969 return ref_transaction_update(transaction, refname,
970 null_sha1, old_sha1,
971 flags, msg, err);
972 }
973
974 int ref_transaction_verify(struct ref_transaction *transaction,
975 const char *refname,
976 const unsigned char *old_sha1,
977 unsigned int flags,
978 struct strbuf *err)
979 {
980 if (!old_sha1)
981 die("BUG: verify called with old_sha1 set to NULL");
982 return ref_transaction_update(transaction, refname,
983 NULL, old_sha1,
984 flags, NULL, err);
985 }
986
987 int update_ref_oid(const char *msg, const char *refname,
988 const struct object_id *new_oid, const struct object_id *old_oid,
989 unsigned int flags, enum action_on_err onerr)
990 {
991 return update_ref(msg, refname, new_oid ? new_oid->hash : NULL,
992 old_oid ? old_oid->hash : NULL, flags, onerr);
993 }
994
995 int refs_update_ref(struct ref_store *refs, const char *msg,
996 const char *refname, const unsigned char *new_sha1,
997 const unsigned char *old_sha1, unsigned int flags,
998 enum action_on_err onerr)
999 {
1000 struct ref_transaction *t = NULL;
1001 struct strbuf err = STRBUF_INIT;
1002 int ret = 0;
1003
1004 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1005 assert(refs == get_main_ref_store());
1006 ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
1007 } else {
1008 t = ref_store_transaction_begin(refs, &err);
1009 if (!t ||
1010 ref_transaction_update(t, refname, new_sha1, old_sha1,
1011 flags, msg, &err) ||
1012 ref_transaction_commit(t, &err)) {
1013 ret = 1;
1014 ref_transaction_free(t);
1015 }
1016 }
1017 if (ret) {
1018 const char *str = "update_ref failed for ref '%s': %s";
1019
1020 switch (onerr) {
1021 case UPDATE_REFS_MSG_ON_ERR:
1022 error(str, refname, err.buf);
1023 break;
1024 case UPDATE_REFS_DIE_ON_ERR:
1025 die(str, refname, err.buf);
1026 break;
1027 case UPDATE_REFS_QUIET_ON_ERR:
1028 break;
1029 }
1030 strbuf_release(&err);
1031 return 1;
1032 }
1033 strbuf_release(&err);
1034 if (t)
1035 ref_transaction_free(t);
1036 return 0;
1037 }
1038
1039 int update_ref(const char *msg, const char *refname,
1040 const unsigned char *new_sha1,
1041 const unsigned char *old_sha1,
1042 unsigned int flags, enum action_on_err onerr)
1043 {
1044 return refs_update_ref(get_main_ref_store(), msg, refname, new_sha1,
1045 old_sha1, flags, onerr);
1046 }
1047
1048 char *shorten_unambiguous_ref(const char *refname, int strict)
1049 {
1050 int i;
1051 static char **scanf_fmts;
1052 static int nr_rules;
1053 char *short_name;
1054 struct strbuf resolved_buf = STRBUF_INIT;
1055
1056 if (!nr_rules) {
1057 /*
1058 * Pre-generate scanf formats from ref_rev_parse_rules[].
1059 * Generate a format suitable for scanf from a
1060 * ref_rev_parse_rules rule by interpolating "%s" at the
1061 * location of the "%.*s".
1062 */
1063 size_t total_len = 0;
1064 size_t offset = 0;
1065
1066 /* the rule list is NULL terminated, count them first */
1067 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1068 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1069 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1070
1071 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1072
1073 offset = 0;
1074 for (i = 0; i < nr_rules; i++) {
1075 assert(offset < total_len);
1076 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1077 offset += snprintf(scanf_fmts[i], total_len - offset,
1078 ref_rev_parse_rules[i], 2, "%s") + 1;
1079 }
1080 }
1081
1082 /* bail out if there are no rules */
1083 if (!nr_rules)
1084 return xstrdup(refname);
1085
1086 /* buffer for scanf result, at most refname must fit */
1087 short_name = xstrdup(refname);
1088
1089 /* skip first rule, it will always match */
1090 for (i = nr_rules - 1; i > 0 ; --i) {
1091 int j;
1092 int rules_to_fail = i;
1093 int short_name_len;
1094
1095 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1096 continue;
1097
1098 short_name_len = strlen(short_name);
1099
1100 /*
1101 * in strict mode, all (except the matched one) rules
1102 * must fail to resolve to a valid non-ambiguous ref
1103 */
1104 if (strict)
1105 rules_to_fail = nr_rules;
1106
1107 /*
1108 * check if the short name resolves to a valid ref,
1109 * but use only rules prior to the matched one
1110 */
1111 for (j = 0; j < rules_to_fail; j++) {
1112 const char *rule = ref_rev_parse_rules[j];
1113
1114 /* skip matched rule */
1115 if (i == j)
1116 continue;
1117
1118 /*
1119 * the short name is ambiguous, if it resolves
1120 * (with this previous rule) to a valid ref
1121 * read_ref() returns 0 on success
1122 */
1123 strbuf_reset(&resolved_buf);
1124 strbuf_addf(&resolved_buf, rule,
1125 short_name_len, short_name);
1126 if (ref_exists(resolved_buf.buf))
1127 break;
1128 }
1129
1130 /*
1131 * short name is non-ambiguous if all previous rules
1132 * haven't resolved to a valid ref
1133 */
1134 if (j == rules_to_fail) {
1135 strbuf_release(&resolved_buf);
1136 return short_name;
1137 }
1138 }
1139
1140 strbuf_release(&resolved_buf);
1141 free(short_name);
1142 return xstrdup(refname);
1143 }
1144
1145 static struct string_list *hide_refs;
1146
1147 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1148 {
1149 const char *key;
1150 if (!strcmp("transfer.hiderefs", var) ||
1151 (!parse_config_key(var, section, NULL, NULL, &key) &&
1152 !strcmp(key, "hiderefs"))) {
1153 char *ref;
1154 int len;
1155
1156 if (!value)
1157 return config_error_nonbool(var);
1158 ref = xstrdup(value);
1159 len = strlen(ref);
1160 while (len && ref[len - 1] == '/')
1161 ref[--len] = '\0';
1162 if (!hide_refs) {
1163 hide_refs = xcalloc(1, sizeof(*hide_refs));
1164 hide_refs->strdup_strings = 1;
1165 }
1166 string_list_append(hide_refs, ref);
1167 }
1168 return 0;
1169 }
1170
1171 int ref_is_hidden(const char *refname, const char *refname_full)
1172 {
1173 int i;
1174
1175 if (!hide_refs)
1176 return 0;
1177 for (i = hide_refs->nr - 1; i >= 0; i--) {
1178 const char *match = hide_refs->items[i].string;
1179 const char *subject;
1180 int neg = 0;
1181 const char *p;
1182
1183 if (*match == '!') {
1184 neg = 1;
1185 match++;
1186 }
1187
1188 if (*match == '^') {
1189 subject = refname_full;
1190 match++;
1191 } else {
1192 subject = refname;
1193 }
1194
1195 /* refname can be NULL when namespaces are used. */
1196 if (subject &&
1197 skip_prefix(subject, match, &p) &&
1198 (!*p || *p == '/'))
1199 return !neg;
1200 }
1201 return 0;
1202 }
1203
1204 const char *find_descendant_ref(const char *dirname,
1205 const struct string_list *extras,
1206 const struct string_list *skip)
1207 {
1208 int pos;
1209
1210 if (!extras)
1211 return NULL;
1212
1213 /*
1214 * Look at the place where dirname would be inserted into
1215 * extras. If there is an entry at that position that starts
1216 * with dirname (remember, dirname includes the trailing
1217 * slash) and is not in skip, then we have a conflict.
1218 */
1219 for (pos = string_list_find_insert_index(extras, dirname, 0);
1220 pos < extras->nr; pos++) {
1221 const char *extra_refname = extras->items[pos].string;
1222
1223 if (!starts_with(extra_refname, dirname))
1224 break;
1225
1226 if (!skip || !string_list_has_string(skip, extra_refname))
1227 return extra_refname;
1228 }
1229 return NULL;
1230 }
1231
1232 int refs_rename_ref_available(struct ref_store *refs,
1233 const char *old_refname,
1234 const char *new_refname)
1235 {
1236 struct string_list skip = STRING_LIST_INIT_NODUP;
1237 struct strbuf err = STRBUF_INIT;
1238 int ok;
1239
1240 string_list_insert(&skip, old_refname);
1241 ok = !refs_verify_refname_available(refs, new_refname,
1242 NULL, &skip, &err);
1243 if (!ok)
1244 error("%s", err.buf);
1245
1246 string_list_clear(&skip, 0);
1247 strbuf_release(&err);
1248 return ok;
1249 }
1250
1251 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1252 {
1253 struct object_id oid;
1254 int flag;
1255
1256 if (submodule) {
1257 if (resolve_gitlink_ref(submodule, "HEAD", oid.hash) == 0)
1258 return fn("HEAD", &oid, 0, cb_data);
1259
1260 return 0;
1261 }
1262
1263 if (!read_ref_full("HEAD", RESOLVE_REF_READING, oid.hash, &flag))
1264 return fn("HEAD", &oid, flag, cb_data);
1265
1266 return 0;
1267 }
1268
1269 int head_ref(each_ref_fn fn, void *cb_data)
1270 {
1271 return head_ref_submodule(NULL, fn, cb_data);
1272 }
1273
1274 struct ref_iterator *refs_ref_iterator_begin(
1275 struct ref_store *refs,
1276 const char *prefix, int trim, int flags)
1277 {
1278 struct ref_iterator *iter;
1279
1280 if (ref_paranoia < 0)
1281 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1282 if (ref_paranoia)
1283 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1284
1285 iter = refs->be->iterator_begin(refs, prefix, flags);
1286
1287 /*
1288 * `iterator_begin()` already takes care of prefix, but we
1289 * might need to do some trimming:
1290 */
1291 if (trim)
1292 iter = prefix_ref_iterator_begin(iter, "", trim);
1293
1294 return iter;
1295 }
1296
1297 /*
1298 * Call fn for each reference in the specified submodule for which the
1299 * refname begins with prefix. If trim is non-zero, then trim that
1300 * many characters off the beginning of each refname before passing
1301 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1302 * include broken references in the iteration. If fn ever returns a
1303 * non-zero value, stop the iteration and return that value;
1304 * otherwise, return 0.
1305 */
1306 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1307 each_ref_fn fn, int trim, int flags, void *cb_data)
1308 {
1309 struct ref_iterator *iter;
1310
1311 if (!refs)
1312 return 0;
1313
1314 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1315
1316 return do_for_each_ref_iterator(iter, fn, cb_data);
1317 }
1318
1319 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1320 {
1321 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1322 }
1323
1324 int for_each_ref(each_ref_fn fn, void *cb_data)
1325 {
1326 return refs_for_each_ref(get_main_ref_store(), fn, cb_data);
1327 }
1328
1329 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1330 {
1331 return refs_for_each_ref(get_submodule_ref_store(submodule), fn, cb_data);
1332 }
1333
1334 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1335 each_ref_fn fn, void *cb_data)
1336 {
1337 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1338 }
1339
1340 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1341 {
1342 return refs_for_each_ref_in(get_main_ref_store(), prefix, fn, cb_data);
1343 }
1344
1345 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1346 {
1347 unsigned int flag = 0;
1348
1349 if (broken)
1350 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1351 return do_for_each_ref(get_main_ref_store(),
1352 prefix, fn, 0, flag, cb_data);
1353 }
1354
1355 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1356 each_ref_fn fn, void *cb_data)
1357 {
1358 return refs_for_each_ref_in(get_submodule_ref_store(submodule),
1359 prefix, fn, cb_data);
1360 }
1361
1362 int for_each_fullref_in_submodule(const char *submodule, const char *prefix,
1363 each_ref_fn fn, void *cb_data,
1364 unsigned int broken)
1365 {
1366 unsigned int flag = 0;
1367
1368 if (broken)
1369 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1370 return do_for_each_ref(get_submodule_ref_store(submodule),
1371 prefix, fn, 0, flag, cb_data);
1372 }
1373
1374 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1375 {
1376 return do_for_each_ref(get_main_ref_store(),
1377 git_replace_ref_base, fn,
1378 strlen(git_replace_ref_base),
1379 0, cb_data);
1380 }
1381
1382 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1383 {
1384 struct strbuf buf = STRBUF_INIT;
1385 int ret;
1386 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1387 ret = do_for_each_ref(get_main_ref_store(),
1388 buf.buf, fn, 0, 0, cb_data);
1389 strbuf_release(&buf);
1390 return ret;
1391 }
1392
1393 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1394 {
1395 return do_for_each_ref(refs, "", fn, 0,
1396 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1397 }
1398
1399 int for_each_rawref(each_ref_fn fn, void *cb_data)
1400 {
1401 return refs_for_each_rawref(get_main_ref_store(), fn, cb_data);
1402 }
1403
1404 int refs_read_raw_ref(struct ref_store *ref_store,
1405 const char *refname, unsigned char *sha1,
1406 struct strbuf *referent, unsigned int *type)
1407 {
1408 return ref_store->be->read_raw_ref(ref_store, refname, sha1, referent, type);
1409 }
1410
1411 /* This function needs to return a meaningful errno on failure */
1412 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1413 const char *refname,
1414 int resolve_flags,
1415 unsigned char *sha1, int *flags)
1416 {
1417 static struct strbuf sb_refname = STRBUF_INIT;
1418 int unused_flags;
1419 int symref_count;
1420
1421 if (!flags)
1422 flags = &unused_flags;
1423
1424 *flags = 0;
1425
1426 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1427 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1428 !refname_is_safe(refname)) {
1429 errno = EINVAL;
1430 return NULL;
1431 }
1432
1433 /*
1434 * dwim_ref() uses REF_ISBROKEN to distinguish between
1435 * missing refs and refs that were present but invalid,
1436 * to complain about the latter to stderr.
1437 *
1438 * We don't know whether the ref exists, so don't set
1439 * REF_ISBROKEN yet.
1440 */
1441 *flags |= REF_BAD_NAME;
1442 }
1443
1444 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1445 unsigned int read_flags = 0;
1446
1447 if (refs_read_raw_ref(refs, refname,
1448 sha1, &sb_refname, &read_flags)) {
1449 *flags |= read_flags;
1450 if (errno != ENOENT || (resolve_flags & RESOLVE_REF_READING))
1451 return NULL;
1452 hashclr(sha1);
1453 if (*flags & REF_BAD_NAME)
1454 *flags |= REF_ISBROKEN;
1455 return refname;
1456 }
1457
1458 *flags |= read_flags;
1459
1460 if (!(read_flags & REF_ISSYMREF)) {
1461 if (*flags & REF_BAD_NAME) {
1462 hashclr(sha1);
1463 *flags |= REF_ISBROKEN;
1464 }
1465 return refname;
1466 }
1467
1468 refname = sb_refname.buf;
1469 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1470 hashclr(sha1);
1471 return refname;
1472 }
1473 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1474 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1475 !refname_is_safe(refname)) {
1476 errno = EINVAL;
1477 return NULL;
1478 }
1479
1480 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1481 }
1482 }
1483
1484 errno = ELOOP;
1485 return NULL;
1486 }
1487
1488 /* backend functions */
1489 int refs_init_db(struct strbuf *err)
1490 {
1491 struct ref_store *refs = get_main_ref_store();
1492
1493 return refs->be->init_db(refs, err);
1494 }
1495
1496 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1497 unsigned char *sha1, int *flags)
1498 {
1499 return refs_resolve_ref_unsafe(get_main_ref_store(), refname,
1500 resolve_flags, sha1, flags);
1501 }
1502
1503 int resolve_gitlink_ref(const char *submodule, const char *refname,
1504 unsigned char *sha1)
1505 {
1506 size_t len = strlen(submodule);
1507 struct ref_store *refs;
1508 int flags;
1509
1510 while (len && submodule[len - 1] == '/')
1511 len--;
1512
1513 if (!len)
1514 return -1;
1515
1516 if (submodule[len]) {
1517 /* We need to strip off one or more trailing slashes */
1518 char *stripped = xmemdupz(submodule, len);
1519
1520 refs = get_submodule_ref_store(stripped);
1521 free(stripped);
1522 } else {
1523 refs = get_submodule_ref_store(submodule);
1524 }
1525
1526 if (!refs)
1527 return -1;
1528
1529 if (!refs_resolve_ref_unsafe(refs, refname, 0, sha1, &flags) ||
1530 is_null_sha1(sha1))
1531 return -1;
1532 return 0;
1533 }
1534
1535 struct ref_store_hash_entry
1536 {
1537 struct hashmap_entry ent; /* must be the first member! */
1538
1539 struct ref_store *refs;
1540
1541 /* NUL-terminated identifier of the ref store: */
1542 char name[FLEX_ARRAY];
1543 };
1544
1545 static int ref_store_hash_cmp(const void *unused_cmp_data,
1546 const void *entry, const void *entry_or_key,
1547 const void *keydata)
1548 {
1549 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1550 const char *name = keydata ? keydata : e2->name;
1551
1552 return strcmp(e1->name, name);
1553 }
1554
1555 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1556 const char *name, struct ref_store *refs)
1557 {
1558 struct ref_store_hash_entry *entry;
1559
1560 FLEX_ALLOC_STR(entry, name, name);
1561 hashmap_entry_init(entry, strhash(name));
1562 entry->refs = refs;
1563 return entry;
1564 }
1565
1566 /* A pointer to the ref_store for the main repository: */
1567 static struct ref_store *main_ref_store;
1568
1569 /* A hashmap of ref_stores, stored by submodule name: */
1570 static struct hashmap submodule_ref_stores;
1571
1572 /* A hashmap of ref_stores, stored by worktree id: */
1573 static struct hashmap worktree_ref_stores;
1574
1575 /*
1576 * Look up a ref store by name. If that ref_store hasn't been
1577 * registered yet, return NULL.
1578 */
1579 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1580 const char *name)
1581 {
1582 struct ref_store_hash_entry *entry;
1583
1584 if (!map->tablesize)
1585 /* It's initialized on demand in register_ref_store(). */
1586 return NULL;
1587
1588 entry = hashmap_get_from_hash(map, strhash(name), name);
1589 return entry ? entry->refs : NULL;
1590 }
1591
1592 /*
1593 * Create, record, and return a ref_store instance for the specified
1594 * gitdir.
1595 */
1596 static struct ref_store *ref_store_init(const char *gitdir,
1597 unsigned int flags)
1598 {
1599 const char *be_name = "files";
1600 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1601 struct ref_store *refs;
1602
1603 if (!be)
1604 die("BUG: reference backend %s is unknown", be_name);
1605
1606 refs = be->init(gitdir, flags);
1607 return refs;
1608 }
1609
1610 struct ref_store *get_main_ref_store(void)
1611 {
1612 if (main_ref_store)
1613 return main_ref_store;
1614
1615 main_ref_store = ref_store_init(get_git_dir(), REF_STORE_ALL_CAPS);
1616 return main_ref_store;
1617 }
1618
1619 /*
1620 * Associate a ref store with a name. It is a fatal error to call this
1621 * function twice for the same name.
1622 */
1623 static void register_ref_store_map(struct hashmap *map,
1624 const char *type,
1625 struct ref_store *refs,
1626 const char *name)
1627 {
1628 if (!map->tablesize)
1629 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1630
1631 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1632 die("BUG: %s ref_store '%s' initialized twice", type, name);
1633 }
1634
1635 struct ref_store *get_submodule_ref_store(const char *submodule)
1636 {
1637 struct strbuf submodule_sb = STRBUF_INIT;
1638 struct ref_store *refs;
1639 int ret;
1640
1641 if (!submodule || !*submodule) {
1642 /*
1643 * FIXME: This case is ideally not allowed. But that
1644 * can't happen until we clean up all the callers.
1645 */
1646 return get_main_ref_store();
1647 }
1648
1649 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1650 if (refs)
1651 return refs;
1652
1653 strbuf_addstr(&submodule_sb, submodule);
1654 ret = is_nonbare_repository_dir(&submodule_sb);
1655 strbuf_release(&submodule_sb);
1656 if (!ret)
1657 return NULL;
1658
1659 ret = submodule_to_gitdir(&submodule_sb, submodule);
1660 if (ret) {
1661 strbuf_release(&submodule_sb);
1662 return NULL;
1663 }
1664
1665 /* assume that add_submodule_odb() has been called */
1666 refs = ref_store_init(submodule_sb.buf,
1667 REF_STORE_READ | REF_STORE_ODB);
1668 register_ref_store_map(&submodule_ref_stores, "submodule",
1669 refs, submodule);
1670
1671 strbuf_release(&submodule_sb);
1672 return refs;
1673 }
1674
1675 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1676 {
1677 struct ref_store *refs;
1678 const char *id;
1679
1680 if (wt->is_current)
1681 return get_main_ref_store();
1682
1683 id = wt->id ? wt->id : "/";
1684 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1685 if (refs)
1686 return refs;
1687
1688 if (wt->id)
1689 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1690 REF_STORE_ALL_CAPS);
1691 else
1692 refs = ref_store_init(get_git_common_dir(),
1693 REF_STORE_ALL_CAPS);
1694
1695 if (refs)
1696 register_ref_store_map(&worktree_ref_stores, "worktree",
1697 refs, id);
1698 return refs;
1699 }
1700
1701 void base_ref_store_init(struct ref_store *refs,
1702 const struct ref_storage_be *be)
1703 {
1704 refs->be = be;
1705 }
1706
1707 /* backend functions */
1708 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1709 {
1710 return refs->be->pack_refs(refs, flags);
1711 }
1712
1713 int refs_peel_ref(struct ref_store *refs, const char *refname,
1714 unsigned char *sha1)
1715 {
1716 return refs->be->peel_ref(refs, refname, sha1);
1717 }
1718
1719 int peel_ref(const char *refname, unsigned char *sha1)
1720 {
1721 return refs_peel_ref(get_main_ref_store(), refname, sha1);
1722 }
1723
1724 int refs_create_symref(struct ref_store *refs,
1725 const char *ref_target,
1726 const char *refs_heads_master,
1727 const char *logmsg)
1728 {
1729 return refs->be->create_symref(refs, ref_target,
1730 refs_heads_master,
1731 logmsg);
1732 }
1733
1734 int create_symref(const char *ref_target, const char *refs_heads_master,
1735 const char *logmsg)
1736 {
1737 return refs_create_symref(get_main_ref_store(), ref_target,
1738 refs_heads_master, logmsg);
1739 }
1740
1741 int ref_update_reject_duplicates(struct string_list *refnames,
1742 struct strbuf *err)
1743 {
1744 size_t i, n = refnames->nr;
1745
1746 assert(err);
1747
1748 for (i = 1; i < n; i++) {
1749 int cmp = strcmp(refnames->items[i - 1].string,
1750 refnames->items[i].string);
1751
1752 if (!cmp) {
1753 strbuf_addf(err,
1754 "multiple updates for ref '%s' not allowed.",
1755 refnames->items[i].string);
1756 return 1;
1757 } else if (cmp > 0) {
1758 die("BUG: ref_update_reject_duplicates() received unsorted list");
1759 }
1760 }
1761 return 0;
1762 }
1763
1764 int ref_transaction_prepare(struct ref_transaction *transaction,
1765 struct strbuf *err)
1766 {
1767 struct ref_store *refs = transaction->ref_store;
1768
1769 switch (transaction->state) {
1770 case REF_TRANSACTION_OPEN:
1771 /* Good. */
1772 break;
1773 case REF_TRANSACTION_PREPARED:
1774 die("BUG: prepare called twice on reference transaction");
1775 break;
1776 case REF_TRANSACTION_CLOSED:
1777 die("BUG: prepare called on a closed reference transaction");
1778 break;
1779 default:
1780 die("BUG: unexpected reference transaction state");
1781 break;
1782 }
1783
1784 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1785 strbuf_addstr(err,
1786 _("ref updates forbidden inside quarantine environment"));
1787 return -1;
1788 }
1789
1790 return refs->be->transaction_prepare(refs, transaction, err);
1791 }
1792
1793 int ref_transaction_abort(struct ref_transaction *transaction,
1794 struct strbuf *err)
1795 {
1796 struct ref_store *refs = transaction->ref_store;
1797 int ret = 0;
1798
1799 switch (transaction->state) {
1800 case REF_TRANSACTION_OPEN:
1801 /* No need to abort explicitly. */
1802 break;
1803 case REF_TRANSACTION_PREPARED:
1804 ret = refs->be->transaction_abort(refs, transaction, err);
1805 break;
1806 case REF_TRANSACTION_CLOSED:
1807 die("BUG: abort called on a closed reference transaction");
1808 break;
1809 default:
1810 die("BUG: unexpected reference transaction state");
1811 break;
1812 }
1813
1814 ref_transaction_free(transaction);
1815 return ret;
1816 }
1817
1818 int ref_transaction_commit(struct ref_transaction *transaction,
1819 struct strbuf *err)
1820 {
1821 struct ref_store *refs = transaction->ref_store;
1822 int ret;
1823
1824 switch (transaction->state) {
1825 case REF_TRANSACTION_OPEN:
1826 /* Need to prepare first. */
1827 ret = ref_transaction_prepare(transaction, err);
1828 if (ret)
1829 return ret;
1830 break;
1831 case REF_TRANSACTION_PREPARED:
1832 /* Fall through to finish. */
1833 break;
1834 case REF_TRANSACTION_CLOSED:
1835 die("BUG: commit called on a closed reference transaction");
1836 break;
1837 default:
1838 die("BUG: unexpected reference transaction state");
1839 break;
1840 }
1841
1842 return refs->be->transaction_finish(refs, transaction, err);
1843 }
1844
1845 int refs_verify_refname_available(struct ref_store *refs,
1846 const char *refname,
1847 const struct string_list *extras,
1848 const struct string_list *skip,
1849 struct strbuf *err)
1850 {
1851 const char *slash;
1852 const char *extra_refname;
1853 struct strbuf dirname = STRBUF_INIT;
1854 struct strbuf referent = STRBUF_INIT;
1855 struct object_id oid;
1856 unsigned int type;
1857 struct ref_iterator *iter;
1858 int ok;
1859 int ret = -1;
1860
1861 /*
1862 * For the sake of comments in this function, suppose that
1863 * refname is "refs/foo/bar".
1864 */
1865
1866 assert(err);
1867
1868 strbuf_grow(&dirname, strlen(refname) + 1);
1869 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1870 /* Expand dirname to the new prefix, not including the trailing slash: */
1871 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1872
1873 /*
1874 * We are still at a leading dir of the refname (e.g.,
1875 * "refs/foo"; if there is a reference with that name,
1876 * it is a conflict, *unless* it is in skip.
1877 */
1878 if (skip && string_list_has_string(skip, dirname.buf))
1879 continue;
1880
1881 if (!refs_read_raw_ref(refs, dirname.buf, oid.hash, &referent, &type)) {
1882 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1883 dirname.buf, refname);
1884 goto cleanup;
1885 }
1886
1887 if (extras && string_list_has_string(extras, dirname.buf)) {
1888 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1889 refname, dirname.buf);
1890 goto cleanup;
1891 }
1892 }
1893
1894 /*
1895 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1896 * There is no point in searching for a reference with that
1897 * name, because a refname isn't considered to conflict with
1898 * itself. But we still need to check for references whose
1899 * names are in the "refs/foo/bar/" namespace, because they
1900 * *do* conflict.
1901 */
1902 strbuf_addstr(&dirname, refname + dirname.len);
1903 strbuf_addch(&dirname, '/');
1904
1905 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
1906 DO_FOR_EACH_INCLUDE_BROKEN);
1907 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
1908 if (skip &&
1909 string_list_has_string(skip, iter->refname))
1910 continue;
1911
1912 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1913 iter->refname, refname);
1914 ref_iterator_abort(iter);
1915 goto cleanup;
1916 }
1917
1918 if (ok != ITER_DONE)
1919 die("BUG: error while iterating over references");
1920
1921 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
1922 if (extra_refname)
1923 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1924 refname, extra_refname);
1925 else
1926 ret = 0;
1927
1928 cleanup:
1929 strbuf_release(&referent);
1930 strbuf_release(&dirname);
1931 return ret;
1932 }
1933
1934 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1935 {
1936 struct ref_iterator *iter;
1937
1938 iter = refs->be->reflog_iterator_begin(refs);
1939
1940 return do_for_each_ref_iterator(iter, fn, cb_data);
1941 }
1942
1943 int for_each_reflog(each_ref_fn fn, void *cb_data)
1944 {
1945 return refs_for_each_reflog(get_main_ref_store(), fn, cb_data);
1946 }
1947
1948 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
1949 const char *refname,
1950 each_reflog_ent_fn fn,
1951 void *cb_data)
1952 {
1953 return refs->be->for_each_reflog_ent_reverse(refs, refname,
1954 fn, cb_data);
1955 }
1956
1957 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
1958 void *cb_data)
1959 {
1960 return refs_for_each_reflog_ent_reverse(get_main_ref_store(),
1961 refname, fn, cb_data);
1962 }
1963
1964 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
1965 each_reflog_ent_fn fn, void *cb_data)
1966 {
1967 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
1968 }
1969
1970 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
1971 void *cb_data)
1972 {
1973 return refs_for_each_reflog_ent(get_main_ref_store(), refname,
1974 fn, cb_data);
1975 }
1976
1977 int refs_reflog_exists(struct ref_store *refs, const char *refname)
1978 {
1979 return refs->be->reflog_exists(refs, refname);
1980 }
1981
1982 int reflog_exists(const char *refname)
1983 {
1984 return refs_reflog_exists(get_main_ref_store(), refname);
1985 }
1986
1987 int refs_create_reflog(struct ref_store *refs, const char *refname,
1988 int force_create, struct strbuf *err)
1989 {
1990 return refs->be->create_reflog(refs, refname, force_create, err);
1991 }
1992
1993 int safe_create_reflog(const char *refname, int force_create,
1994 struct strbuf *err)
1995 {
1996 return refs_create_reflog(get_main_ref_store(), refname,
1997 force_create, err);
1998 }
1999
2000 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2001 {
2002 return refs->be->delete_reflog(refs, refname);
2003 }
2004
2005 int delete_reflog(const char *refname)
2006 {
2007 return refs_delete_reflog(get_main_ref_store(), refname);
2008 }
2009
2010 int refs_reflog_expire(struct ref_store *refs,
2011 const char *refname, const unsigned char *sha1,
2012 unsigned int flags,
2013 reflog_expiry_prepare_fn prepare_fn,
2014 reflog_expiry_should_prune_fn should_prune_fn,
2015 reflog_expiry_cleanup_fn cleanup_fn,
2016 void *policy_cb_data)
2017 {
2018 return refs->be->reflog_expire(refs, refname, sha1, flags,
2019 prepare_fn, should_prune_fn,
2020 cleanup_fn, policy_cb_data);
2021 }
2022
2023 int reflog_expire(const char *refname, const unsigned char *sha1,
2024 unsigned int flags,
2025 reflog_expiry_prepare_fn prepare_fn,
2026 reflog_expiry_should_prune_fn should_prune_fn,
2027 reflog_expiry_cleanup_fn cleanup_fn,
2028 void *policy_cb_data)
2029 {
2030 return refs_reflog_expire(get_main_ref_store(),
2031 refname, sha1, flags,
2032 prepare_fn, should_prune_fn,
2033 cleanup_fn, policy_cb_data);
2034 }
2035
2036 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2037 struct strbuf *err)
2038 {
2039 struct ref_store *refs = transaction->ref_store;
2040
2041 return refs->be->initial_transaction_commit(refs, transaction, err);
2042 }
2043
2044 int refs_delete_refs(struct ref_store *refs, const char *msg,
2045 struct string_list *refnames, unsigned int flags)
2046 {
2047 return refs->be->delete_refs(refs, msg, refnames, flags);
2048 }
2049
2050 int delete_refs(const char *msg, struct string_list *refnames,
2051 unsigned int flags)
2052 {
2053 return refs_delete_refs(get_main_ref_store(), msg, refnames, flags);
2054 }
2055
2056 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2057 const char *newref, const char *logmsg)
2058 {
2059 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2060 }
2061
2062 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2063 {
2064 return refs_rename_ref(get_main_ref_store(), oldref, newref, logmsg);
2065 }