push, fetch: error out for submodule entries not pointing to commits
[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 long get_files_ref_lock_timeout_ms(void)
583 {
584 static int configured = 0;
585
586 /* The default timeout is 100 ms: */
587 static int timeout_ms = 100;
588
589 if (!configured) {
590 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
591 configured = 1;
592 }
593
594 return timeout_ms;
595 }
596
597 static int write_pseudoref(const char *pseudoref, const unsigned char *sha1,
598 const unsigned char *old_sha1, struct strbuf *err)
599 {
600 const char *filename;
601 int fd;
602 static struct lock_file lock;
603 struct strbuf buf = STRBUF_INIT;
604 int ret = -1;
605
606 strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
607
608 filename = git_path("%s", pseudoref);
609 fd = hold_lock_file_for_update_timeout(&lock, filename,
610 LOCK_DIE_ON_ERROR,
611 get_files_ref_lock_timeout_ms());
612 if (fd < 0) {
613 strbuf_addf(err, "could not open '%s' for writing: %s",
614 filename, strerror(errno));
615 return -1;
616 }
617
618 if (old_sha1) {
619 unsigned char actual_old_sha1[20];
620
621 if (read_ref(pseudoref, actual_old_sha1))
622 die("could not read ref '%s'", pseudoref);
623 if (hashcmp(actual_old_sha1, old_sha1)) {
624 strbuf_addf(err, "unexpected sha1 when writing '%s'", pseudoref);
625 rollback_lock_file(&lock);
626 goto done;
627 }
628 }
629
630 if (write_in_full(fd, buf.buf, buf.len) != buf.len) {
631 strbuf_addf(err, "could not write to '%s'", filename);
632 rollback_lock_file(&lock);
633 goto done;
634 }
635
636 commit_lock_file(&lock);
637 ret = 0;
638 done:
639 strbuf_release(&buf);
640 return ret;
641 }
642
643 static int delete_pseudoref(const char *pseudoref, const unsigned char *old_sha1)
644 {
645 static struct lock_file lock;
646 const char *filename;
647
648 filename = git_path("%s", pseudoref);
649
650 if (old_sha1 && !is_null_sha1(old_sha1)) {
651 int fd;
652 unsigned char actual_old_sha1[20];
653
654 fd = hold_lock_file_for_update_timeout(
655 &lock, filename, LOCK_DIE_ON_ERROR,
656 get_files_ref_lock_timeout_ms());
657 if (fd < 0)
658 die_errno(_("Could not open '%s' for writing"), filename);
659 if (read_ref(pseudoref, actual_old_sha1))
660 die("could not read ref '%s'", pseudoref);
661 if (hashcmp(actual_old_sha1, old_sha1)) {
662 warning("Unexpected sha1 when deleting %s", pseudoref);
663 rollback_lock_file(&lock);
664 return -1;
665 }
666
667 unlink(filename);
668 rollback_lock_file(&lock);
669 } else {
670 unlink(filename);
671 }
672
673 return 0;
674 }
675
676 int refs_delete_ref(struct ref_store *refs, const char *msg,
677 const char *refname,
678 const unsigned char *old_sha1,
679 unsigned int flags)
680 {
681 struct ref_transaction *transaction;
682 struct strbuf err = STRBUF_INIT;
683
684 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
685 assert(refs == get_main_ref_store());
686 return delete_pseudoref(refname, old_sha1);
687 }
688
689 transaction = ref_store_transaction_begin(refs, &err);
690 if (!transaction ||
691 ref_transaction_delete(transaction, refname, old_sha1,
692 flags, msg, &err) ||
693 ref_transaction_commit(transaction, &err)) {
694 error("%s", err.buf);
695 ref_transaction_free(transaction);
696 strbuf_release(&err);
697 return 1;
698 }
699 ref_transaction_free(transaction);
700 strbuf_release(&err);
701 return 0;
702 }
703
704 int delete_ref(const char *msg, const char *refname,
705 const unsigned char *old_sha1, unsigned int flags)
706 {
707 return refs_delete_ref(get_main_ref_store(), msg, refname,
708 old_sha1, flags);
709 }
710
711 int copy_reflog_msg(char *buf, const char *msg)
712 {
713 char *cp = buf;
714 char c;
715 int wasspace = 1;
716
717 *cp++ = '\t';
718 while ((c = *msg++)) {
719 if (wasspace && isspace(c))
720 continue;
721 wasspace = isspace(c);
722 if (wasspace)
723 c = ' ';
724 *cp++ = c;
725 }
726 while (buf < cp && isspace(cp[-1]))
727 cp--;
728 *cp++ = '\n';
729 return cp - buf;
730 }
731
732 int should_autocreate_reflog(const char *refname)
733 {
734 switch (log_all_ref_updates) {
735 case LOG_REFS_ALWAYS:
736 return 1;
737 case LOG_REFS_NORMAL:
738 return starts_with(refname, "refs/heads/") ||
739 starts_with(refname, "refs/remotes/") ||
740 starts_with(refname, "refs/notes/") ||
741 !strcmp(refname, "HEAD");
742 default:
743 return 0;
744 }
745 }
746
747 int is_branch(const char *refname)
748 {
749 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
750 }
751
752 struct read_ref_at_cb {
753 const char *refname;
754 timestamp_t at_time;
755 int cnt;
756 int reccnt;
757 unsigned char *sha1;
758 int found_it;
759
760 unsigned char osha1[20];
761 unsigned char nsha1[20];
762 int tz;
763 timestamp_t date;
764 char **msg;
765 timestamp_t *cutoff_time;
766 int *cutoff_tz;
767 int *cutoff_cnt;
768 };
769
770 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
771 const char *email, timestamp_t timestamp, int tz,
772 const char *message, void *cb_data)
773 {
774 struct read_ref_at_cb *cb = cb_data;
775
776 cb->reccnt++;
777 cb->tz = tz;
778 cb->date = timestamp;
779
780 if (timestamp <= cb->at_time || cb->cnt == 0) {
781 if (cb->msg)
782 *cb->msg = xstrdup(message);
783 if (cb->cutoff_time)
784 *cb->cutoff_time = timestamp;
785 if (cb->cutoff_tz)
786 *cb->cutoff_tz = tz;
787 if (cb->cutoff_cnt)
788 *cb->cutoff_cnt = cb->reccnt - 1;
789 /*
790 * we have not yet updated cb->[n|o]sha1 so they still
791 * hold the values for the previous record.
792 */
793 if (!is_null_sha1(cb->osha1)) {
794 hashcpy(cb->sha1, noid->hash);
795 if (hashcmp(cb->osha1, noid->hash))
796 warning("Log for ref %s has gap after %s.",
797 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
798 }
799 else if (cb->date == cb->at_time)
800 hashcpy(cb->sha1, noid->hash);
801 else if (hashcmp(noid->hash, cb->sha1))
802 warning("Log for ref %s unexpectedly ended on %s.",
803 cb->refname, show_date(cb->date, cb->tz,
804 DATE_MODE(RFC2822)));
805 hashcpy(cb->osha1, ooid->hash);
806 hashcpy(cb->nsha1, noid->hash);
807 cb->found_it = 1;
808 return 1;
809 }
810 hashcpy(cb->osha1, ooid->hash);
811 hashcpy(cb->nsha1, noid->hash);
812 if (cb->cnt > 0)
813 cb->cnt--;
814 return 0;
815 }
816
817 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
818 const char *email, timestamp_t timestamp,
819 int tz, const char *message, void *cb_data)
820 {
821 struct read_ref_at_cb *cb = cb_data;
822
823 if (cb->msg)
824 *cb->msg = xstrdup(message);
825 if (cb->cutoff_time)
826 *cb->cutoff_time = timestamp;
827 if (cb->cutoff_tz)
828 *cb->cutoff_tz = tz;
829 if (cb->cutoff_cnt)
830 *cb->cutoff_cnt = cb->reccnt;
831 hashcpy(cb->sha1, ooid->hash);
832 if (is_null_sha1(cb->sha1))
833 hashcpy(cb->sha1, noid->hash);
834 /* We just want the first entry */
835 return 1;
836 }
837
838 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
839 unsigned char *sha1, char **msg,
840 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
841 {
842 struct read_ref_at_cb cb;
843
844 memset(&cb, 0, sizeof(cb));
845 cb.refname = refname;
846 cb.at_time = at_time;
847 cb.cnt = cnt;
848 cb.msg = msg;
849 cb.cutoff_time = cutoff_time;
850 cb.cutoff_tz = cutoff_tz;
851 cb.cutoff_cnt = cutoff_cnt;
852 cb.sha1 = sha1;
853
854 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
855
856 if (!cb.reccnt) {
857 if (flags & GET_OID_QUIETLY)
858 exit(128);
859 else
860 die("Log for %s is empty.", refname);
861 }
862 if (cb.found_it)
863 return 0;
864
865 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
866
867 return 1;
868 }
869
870 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
871 struct strbuf *err)
872 {
873 struct ref_transaction *tr;
874 assert(err);
875
876 tr = xcalloc(1, sizeof(struct ref_transaction));
877 tr->ref_store = refs;
878 return tr;
879 }
880
881 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
882 {
883 return ref_store_transaction_begin(get_main_ref_store(), err);
884 }
885
886 void ref_transaction_free(struct ref_transaction *transaction)
887 {
888 size_t i;
889
890 if (!transaction)
891 return;
892
893 switch (transaction->state) {
894 case REF_TRANSACTION_OPEN:
895 case REF_TRANSACTION_CLOSED:
896 /* OK */
897 break;
898 case REF_TRANSACTION_PREPARED:
899 die("BUG: free called on a prepared reference transaction");
900 break;
901 default:
902 die("BUG: unexpected reference transaction state");
903 break;
904 }
905
906 for (i = 0; i < transaction->nr; i++) {
907 free(transaction->updates[i]->msg);
908 free(transaction->updates[i]);
909 }
910 free(transaction->updates);
911 free(transaction);
912 }
913
914 struct ref_update *ref_transaction_add_update(
915 struct ref_transaction *transaction,
916 const char *refname, unsigned int flags,
917 const unsigned char *new_sha1,
918 const unsigned char *old_sha1,
919 const char *msg)
920 {
921 struct ref_update *update;
922
923 if (transaction->state != REF_TRANSACTION_OPEN)
924 die("BUG: update called for transaction that is not open");
925
926 if ((flags & REF_ISPRUNING) && !(flags & REF_NODEREF))
927 die("BUG: REF_ISPRUNING set without REF_NODEREF");
928
929 FLEX_ALLOC_STR(update, refname, refname);
930 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
931 transaction->updates[transaction->nr++] = update;
932
933 update->flags = flags;
934
935 if (flags & REF_HAVE_NEW)
936 hashcpy(update->new_oid.hash, new_sha1);
937 if (flags & REF_HAVE_OLD)
938 hashcpy(update->old_oid.hash, old_sha1);
939 update->msg = xstrdup_or_null(msg);
940 return update;
941 }
942
943 int ref_transaction_update(struct ref_transaction *transaction,
944 const char *refname,
945 const unsigned char *new_sha1,
946 const unsigned char *old_sha1,
947 unsigned int flags, const char *msg,
948 struct strbuf *err)
949 {
950 assert(err);
951
952 if ((new_sha1 && !is_null_sha1(new_sha1)) ?
953 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
954 !refname_is_safe(refname)) {
955 strbuf_addf(err, "refusing to update ref with bad name '%s'",
956 refname);
957 return -1;
958 }
959
960 flags |= (new_sha1 ? REF_HAVE_NEW : 0) | (old_sha1 ? REF_HAVE_OLD : 0);
961
962 ref_transaction_add_update(transaction, refname, flags,
963 new_sha1, old_sha1, msg);
964 return 0;
965 }
966
967 int ref_transaction_create(struct ref_transaction *transaction,
968 const char *refname,
969 const unsigned char *new_sha1,
970 unsigned int flags, const char *msg,
971 struct strbuf *err)
972 {
973 if (!new_sha1 || is_null_sha1(new_sha1))
974 die("BUG: create called without valid new_sha1");
975 return ref_transaction_update(transaction, refname, new_sha1,
976 null_sha1, flags, msg, err);
977 }
978
979 int ref_transaction_delete(struct ref_transaction *transaction,
980 const char *refname,
981 const unsigned char *old_sha1,
982 unsigned int flags, const char *msg,
983 struct strbuf *err)
984 {
985 if (old_sha1 && is_null_sha1(old_sha1))
986 die("BUG: delete called with old_sha1 set to zeros");
987 return ref_transaction_update(transaction, refname,
988 null_sha1, old_sha1,
989 flags, msg, err);
990 }
991
992 int ref_transaction_verify(struct ref_transaction *transaction,
993 const char *refname,
994 const unsigned char *old_sha1,
995 unsigned int flags,
996 struct strbuf *err)
997 {
998 if (!old_sha1)
999 die("BUG: verify called with old_sha1 set to NULL");
1000 return ref_transaction_update(transaction, refname,
1001 NULL, old_sha1,
1002 flags, NULL, err);
1003 }
1004
1005 int update_ref_oid(const char *msg, const char *refname,
1006 const struct object_id *new_oid, const struct object_id *old_oid,
1007 unsigned int flags, enum action_on_err onerr)
1008 {
1009 return update_ref(msg, refname, new_oid ? new_oid->hash : NULL,
1010 old_oid ? old_oid->hash : NULL, flags, onerr);
1011 }
1012
1013 int refs_update_ref(struct ref_store *refs, const char *msg,
1014 const char *refname, const unsigned char *new_sha1,
1015 const unsigned char *old_sha1, unsigned int flags,
1016 enum action_on_err onerr)
1017 {
1018 struct ref_transaction *t = NULL;
1019 struct strbuf err = STRBUF_INIT;
1020 int ret = 0;
1021
1022 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1023 assert(refs == get_main_ref_store());
1024 ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
1025 } else {
1026 t = ref_store_transaction_begin(refs, &err);
1027 if (!t ||
1028 ref_transaction_update(t, refname, new_sha1, old_sha1,
1029 flags, msg, &err) ||
1030 ref_transaction_commit(t, &err)) {
1031 ret = 1;
1032 ref_transaction_free(t);
1033 }
1034 }
1035 if (ret) {
1036 const char *str = "update_ref failed for ref '%s': %s";
1037
1038 switch (onerr) {
1039 case UPDATE_REFS_MSG_ON_ERR:
1040 error(str, refname, err.buf);
1041 break;
1042 case UPDATE_REFS_DIE_ON_ERR:
1043 die(str, refname, err.buf);
1044 break;
1045 case UPDATE_REFS_QUIET_ON_ERR:
1046 break;
1047 }
1048 strbuf_release(&err);
1049 return 1;
1050 }
1051 strbuf_release(&err);
1052 if (t)
1053 ref_transaction_free(t);
1054 return 0;
1055 }
1056
1057 int update_ref(const char *msg, const char *refname,
1058 const unsigned char *new_sha1,
1059 const unsigned char *old_sha1,
1060 unsigned int flags, enum action_on_err onerr)
1061 {
1062 return refs_update_ref(get_main_ref_store(), msg, refname, new_sha1,
1063 old_sha1, flags, onerr);
1064 }
1065
1066 char *shorten_unambiguous_ref(const char *refname, int strict)
1067 {
1068 int i;
1069 static char **scanf_fmts;
1070 static int nr_rules;
1071 char *short_name;
1072 struct strbuf resolved_buf = STRBUF_INIT;
1073
1074 if (!nr_rules) {
1075 /*
1076 * Pre-generate scanf formats from ref_rev_parse_rules[].
1077 * Generate a format suitable for scanf from a
1078 * ref_rev_parse_rules rule by interpolating "%s" at the
1079 * location of the "%.*s".
1080 */
1081 size_t total_len = 0;
1082 size_t offset = 0;
1083
1084 /* the rule list is NULL terminated, count them first */
1085 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1086 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1087 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1088
1089 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1090
1091 offset = 0;
1092 for (i = 0; i < nr_rules; i++) {
1093 assert(offset < total_len);
1094 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1095 offset += snprintf(scanf_fmts[i], total_len - offset,
1096 ref_rev_parse_rules[i], 2, "%s") + 1;
1097 }
1098 }
1099
1100 /* bail out if there are no rules */
1101 if (!nr_rules)
1102 return xstrdup(refname);
1103
1104 /* buffer for scanf result, at most refname must fit */
1105 short_name = xstrdup(refname);
1106
1107 /* skip first rule, it will always match */
1108 for (i = nr_rules - 1; i > 0 ; --i) {
1109 int j;
1110 int rules_to_fail = i;
1111 int short_name_len;
1112
1113 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1114 continue;
1115
1116 short_name_len = strlen(short_name);
1117
1118 /*
1119 * in strict mode, all (except the matched one) rules
1120 * must fail to resolve to a valid non-ambiguous ref
1121 */
1122 if (strict)
1123 rules_to_fail = nr_rules;
1124
1125 /*
1126 * check if the short name resolves to a valid ref,
1127 * but use only rules prior to the matched one
1128 */
1129 for (j = 0; j < rules_to_fail; j++) {
1130 const char *rule = ref_rev_parse_rules[j];
1131
1132 /* skip matched rule */
1133 if (i == j)
1134 continue;
1135
1136 /*
1137 * the short name is ambiguous, if it resolves
1138 * (with this previous rule) to a valid ref
1139 * read_ref() returns 0 on success
1140 */
1141 strbuf_reset(&resolved_buf);
1142 strbuf_addf(&resolved_buf, rule,
1143 short_name_len, short_name);
1144 if (ref_exists(resolved_buf.buf))
1145 break;
1146 }
1147
1148 /*
1149 * short name is non-ambiguous if all previous rules
1150 * haven't resolved to a valid ref
1151 */
1152 if (j == rules_to_fail) {
1153 strbuf_release(&resolved_buf);
1154 return short_name;
1155 }
1156 }
1157
1158 strbuf_release(&resolved_buf);
1159 free(short_name);
1160 return xstrdup(refname);
1161 }
1162
1163 static struct string_list *hide_refs;
1164
1165 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1166 {
1167 const char *key;
1168 if (!strcmp("transfer.hiderefs", var) ||
1169 (!parse_config_key(var, section, NULL, NULL, &key) &&
1170 !strcmp(key, "hiderefs"))) {
1171 char *ref;
1172 int len;
1173
1174 if (!value)
1175 return config_error_nonbool(var);
1176 ref = xstrdup(value);
1177 len = strlen(ref);
1178 while (len && ref[len - 1] == '/')
1179 ref[--len] = '\0';
1180 if (!hide_refs) {
1181 hide_refs = xcalloc(1, sizeof(*hide_refs));
1182 hide_refs->strdup_strings = 1;
1183 }
1184 string_list_append(hide_refs, ref);
1185 }
1186 return 0;
1187 }
1188
1189 int ref_is_hidden(const char *refname, const char *refname_full)
1190 {
1191 int i;
1192
1193 if (!hide_refs)
1194 return 0;
1195 for (i = hide_refs->nr - 1; i >= 0; i--) {
1196 const char *match = hide_refs->items[i].string;
1197 const char *subject;
1198 int neg = 0;
1199 const char *p;
1200
1201 if (*match == '!') {
1202 neg = 1;
1203 match++;
1204 }
1205
1206 if (*match == '^') {
1207 subject = refname_full;
1208 match++;
1209 } else {
1210 subject = refname;
1211 }
1212
1213 /* refname can be NULL when namespaces are used. */
1214 if (subject &&
1215 skip_prefix(subject, match, &p) &&
1216 (!*p || *p == '/'))
1217 return !neg;
1218 }
1219 return 0;
1220 }
1221
1222 const char *find_descendant_ref(const char *dirname,
1223 const struct string_list *extras,
1224 const struct string_list *skip)
1225 {
1226 int pos;
1227
1228 if (!extras)
1229 return NULL;
1230
1231 /*
1232 * Look at the place where dirname would be inserted into
1233 * extras. If there is an entry at that position that starts
1234 * with dirname (remember, dirname includes the trailing
1235 * slash) and is not in skip, then we have a conflict.
1236 */
1237 for (pos = string_list_find_insert_index(extras, dirname, 0);
1238 pos < extras->nr; pos++) {
1239 const char *extra_refname = extras->items[pos].string;
1240
1241 if (!starts_with(extra_refname, dirname))
1242 break;
1243
1244 if (!skip || !string_list_has_string(skip, extra_refname))
1245 return extra_refname;
1246 }
1247 return NULL;
1248 }
1249
1250 int refs_rename_ref_available(struct ref_store *refs,
1251 const char *old_refname,
1252 const char *new_refname)
1253 {
1254 struct string_list skip = STRING_LIST_INIT_NODUP;
1255 struct strbuf err = STRBUF_INIT;
1256 int ok;
1257
1258 string_list_insert(&skip, old_refname);
1259 ok = !refs_verify_refname_available(refs, new_refname,
1260 NULL, &skip, &err);
1261 if (!ok)
1262 error("%s", err.buf);
1263
1264 string_list_clear(&skip, 0);
1265 strbuf_release(&err);
1266 return ok;
1267 }
1268
1269 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1270 {
1271 struct object_id oid;
1272 int flag;
1273
1274 if (submodule) {
1275 if (resolve_gitlink_ref(submodule, "HEAD", oid.hash) == 0)
1276 return fn("HEAD", &oid, 0, cb_data);
1277
1278 return 0;
1279 }
1280
1281 if (!read_ref_full("HEAD", RESOLVE_REF_READING, oid.hash, &flag))
1282 return fn("HEAD", &oid, flag, cb_data);
1283
1284 return 0;
1285 }
1286
1287 int head_ref(each_ref_fn fn, void *cb_data)
1288 {
1289 return head_ref_submodule(NULL, fn, cb_data);
1290 }
1291
1292 struct ref_iterator *refs_ref_iterator_begin(
1293 struct ref_store *refs,
1294 const char *prefix, int trim, int flags)
1295 {
1296 struct ref_iterator *iter;
1297
1298 if (ref_paranoia < 0)
1299 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1300 if (ref_paranoia)
1301 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1302
1303 iter = refs->be->iterator_begin(refs, prefix, flags);
1304
1305 /*
1306 * `iterator_begin()` already takes care of prefix, but we
1307 * might need to do some trimming:
1308 */
1309 if (trim)
1310 iter = prefix_ref_iterator_begin(iter, "", trim);
1311
1312 return iter;
1313 }
1314
1315 /*
1316 * Call fn for each reference in the specified submodule for which the
1317 * refname begins with prefix. If trim is non-zero, then trim that
1318 * many characters off the beginning of each refname before passing
1319 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1320 * include broken references in the iteration. If fn ever returns a
1321 * non-zero value, stop the iteration and return that value;
1322 * otherwise, return 0.
1323 */
1324 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1325 each_ref_fn fn, int trim, int flags, void *cb_data)
1326 {
1327 struct ref_iterator *iter;
1328
1329 if (!refs)
1330 return 0;
1331
1332 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1333
1334 return do_for_each_ref_iterator(iter, fn, cb_data);
1335 }
1336
1337 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1338 {
1339 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1340 }
1341
1342 int for_each_ref(each_ref_fn fn, void *cb_data)
1343 {
1344 return refs_for_each_ref(get_main_ref_store(), fn, cb_data);
1345 }
1346
1347 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1348 {
1349 return refs_for_each_ref(get_submodule_ref_store(submodule), fn, cb_data);
1350 }
1351
1352 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1353 each_ref_fn fn, void *cb_data)
1354 {
1355 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1356 }
1357
1358 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1359 {
1360 return refs_for_each_ref_in(get_main_ref_store(), prefix, fn, cb_data);
1361 }
1362
1363 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1364 {
1365 unsigned int flag = 0;
1366
1367 if (broken)
1368 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1369 return do_for_each_ref(get_main_ref_store(),
1370 prefix, fn, 0, flag, cb_data);
1371 }
1372
1373 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1374 each_ref_fn fn, void *cb_data)
1375 {
1376 return refs_for_each_ref_in(get_submodule_ref_store(submodule),
1377 prefix, fn, cb_data);
1378 }
1379
1380 int for_each_fullref_in_submodule(const char *submodule, const char *prefix,
1381 each_ref_fn fn, void *cb_data,
1382 unsigned int broken)
1383 {
1384 unsigned int flag = 0;
1385
1386 if (broken)
1387 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1388 return do_for_each_ref(get_submodule_ref_store(submodule),
1389 prefix, fn, 0, flag, cb_data);
1390 }
1391
1392 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1393 {
1394 return do_for_each_ref(get_main_ref_store(),
1395 git_replace_ref_base, fn,
1396 strlen(git_replace_ref_base),
1397 0, cb_data);
1398 }
1399
1400 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1401 {
1402 struct strbuf buf = STRBUF_INIT;
1403 int ret;
1404 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1405 ret = do_for_each_ref(get_main_ref_store(),
1406 buf.buf, fn, 0, 0, cb_data);
1407 strbuf_release(&buf);
1408 return ret;
1409 }
1410
1411 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1412 {
1413 return do_for_each_ref(refs, "", fn, 0,
1414 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1415 }
1416
1417 int for_each_rawref(each_ref_fn fn, void *cb_data)
1418 {
1419 return refs_for_each_rawref(get_main_ref_store(), fn, cb_data);
1420 }
1421
1422 int refs_read_raw_ref(struct ref_store *ref_store,
1423 const char *refname, unsigned char *sha1,
1424 struct strbuf *referent, unsigned int *type)
1425 {
1426 return ref_store->be->read_raw_ref(ref_store, refname, sha1, referent, type);
1427 }
1428
1429 /* This function needs to return a meaningful errno on failure */
1430 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1431 const char *refname,
1432 int resolve_flags,
1433 unsigned char *sha1, int *flags)
1434 {
1435 static struct strbuf sb_refname = STRBUF_INIT;
1436 int unused_flags;
1437 int symref_count;
1438
1439 if (!flags)
1440 flags = &unused_flags;
1441
1442 *flags = 0;
1443
1444 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1445 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1446 !refname_is_safe(refname)) {
1447 errno = EINVAL;
1448 return NULL;
1449 }
1450
1451 /*
1452 * dwim_ref() uses REF_ISBROKEN to distinguish between
1453 * missing refs and refs that were present but invalid,
1454 * to complain about the latter to stderr.
1455 *
1456 * We don't know whether the ref exists, so don't set
1457 * REF_ISBROKEN yet.
1458 */
1459 *flags |= REF_BAD_NAME;
1460 }
1461
1462 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1463 unsigned int read_flags = 0;
1464
1465 if (refs_read_raw_ref(refs, refname,
1466 sha1, &sb_refname, &read_flags)) {
1467 *flags |= read_flags;
1468 if (errno != ENOENT || (resolve_flags & RESOLVE_REF_READING))
1469 return NULL;
1470 hashclr(sha1);
1471 if (*flags & REF_BAD_NAME)
1472 *flags |= REF_ISBROKEN;
1473 return refname;
1474 }
1475
1476 *flags |= read_flags;
1477
1478 if (!(read_flags & REF_ISSYMREF)) {
1479 if (*flags & REF_BAD_NAME) {
1480 hashclr(sha1);
1481 *flags |= REF_ISBROKEN;
1482 }
1483 return refname;
1484 }
1485
1486 refname = sb_refname.buf;
1487 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1488 hashclr(sha1);
1489 return refname;
1490 }
1491 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1492 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1493 !refname_is_safe(refname)) {
1494 errno = EINVAL;
1495 return NULL;
1496 }
1497
1498 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1499 }
1500 }
1501
1502 errno = ELOOP;
1503 return NULL;
1504 }
1505
1506 /* backend functions */
1507 int refs_init_db(struct strbuf *err)
1508 {
1509 struct ref_store *refs = get_main_ref_store();
1510
1511 return refs->be->init_db(refs, err);
1512 }
1513
1514 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1515 unsigned char *sha1, int *flags)
1516 {
1517 return refs_resolve_ref_unsafe(get_main_ref_store(), refname,
1518 resolve_flags, sha1, flags);
1519 }
1520
1521 int resolve_gitlink_ref(const char *submodule, const char *refname,
1522 unsigned char *sha1)
1523 {
1524 size_t len = strlen(submodule);
1525 struct ref_store *refs;
1526 int flags;
1527
1528 while (len && submodule[len - 1] == '/')
1529 len--;
1530
1531 if (!len)
1532 return -1;
1533
1534 if (submodule[len]) {
1535 /* We need to strip off one or more trailing slashes */
1536 char *stripped = xmemdupz(submodule, len);
1537
1538 refs = get_submodule_ref_store(stripped);
1539 free(stripped);
1540 } else {
1541 refs = get_submodule_ref_store(submodule);
1542 }
1543
1544 if (!refs)
1545 return -1;
1546
1547 if (!refs_resolve_ref_unsafe(refs, refname, 0, sha1, &flags) ||
1548 is_null_sha1(sha1))
1549 return -1;
1550 return 0;
1551 }
1552
1553 struct ref_store_hash_entry
1554 {
1555 struct hashmap_entry ent; /* must be the first member! */
1556
1557 struct ref_store *refs;
1558
1559 /* NUL-terminated identifier of the ref store: */
1560 char name[FLEX_ARRAY];
1561 };
1562
1563 static int ref_store_hash_cmp(const void *unused_cmp_data,
1564 const void *entry, const void *entry_or_key,
1565 const void *keydata)
1566 {
1567 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1568 const char *name = keydata ? keydata : e2->name;
1569
1570 return strcmp(e1->name, name);
1571 }
1572
1573 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1574 const char *name, struct ref_store *refs)
1575 {
1576 struct ref_store_hash_entry *entry;
1577
1578 FLEX_ALLOC_STR(entry, name, name);
1579 hashmap_entry_init(entry, strhash(name));
1580 entry->refs = refs;
1581 return entry;
1582 }
1583
1584 /* A pointer to the ref_store for the main repository: */
1585 static struct ref_store *main_ref_store;
1586
1587 /* A hashmap of ref_stores, stored by submodule name: */
1588 static struct hashmap submodule_ref_stores;
1589
1590 /* A hashmap of ref_stores, stored by worktree id: */
1591 static struct hashmap worktree_ref_stores;
1592
1593 /*
1594 * Look up a ref store by name. If that ref_store hasn't been
1595 * registered yet, return NULL.
1596 */
1597 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1598 const char *name)
1599 {
1600 struct ref_store_hash_entry *entry;
1601
1602 if (!map->tablesize)
1603 /* It's initialized on demand in register_ref_store(). */
1604 return NULL;
1605
1606 entry = hashmap_get_from_hash(map, strhash(name), name);
1607 return entry ? entry->refs : NULL;
1608 }
1609
1610 /*
1611 * Create, record, and return a ref_store instance for the specified
1612 * gitdir.
1613 */
1614 static struct ref_store *ref_store_init(const char *gitdir,
1615 unsigned int flags)
1616 {
1617 const char *be_name = "files";
1618 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1619 struct ref_store *refs;
1620
1621 if (!be)
1622 die("BUG: reference backend %s is unknown", be_name);
1623
1624 refs = be->init(gitdir, flags);
1625 return refs;
1626 }
1627
1628 struct ref_store *get_main_ref_store(void)
1629 {
1630 if (main_ref_store)
1631 return main_ref_store;
1632
1633 main_ref_store = ref_store_init(get_git_dir(), REF_STORE_ALL_CAPS);
1634 return main_ref_store;
1635 }
1636
1637 /*
1638 * Associate a ref store with a name. It is a fatal error to call this
1639 * function twice for the same name.
1640 */
1641 static void register_ref_store_map(struct hashmap *map,
1642 const char *type,
1643 struct ref_store *refs,
1644 const char *name)
1645 {
1646 if (!map->tablesize)
1647 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1648
1649 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1650 die("BUG: %s ref_store '%s' initialized twice", type, name);
1651 }
1652
1653 struct ref_store *get_submodule_ref_store(const char *submodule)
1654 {
1655 struct strbuf submodule_sb = STRBUF_INIT;
1656 struct ref_store *refs;
1657 int ret;
1658
1659 if (!submodule || !*submodule) {
1660 /*
1661 * FIXME: This case is ideally not allowed. But that
1662 * can't happen until we clean up all the callers.
1663 */
1664 return get_main_ref_store();
1665 }
1666
1667 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1668 if (refs)
1669 return refs;
1670
1671 strbuf_addstr(&submodule_sb, submodule);
1672 ret = is_nonbare_repository_dir(&submodule_sb);
1673 strbuf_release(&submodule_sb);
1674 if (!ret)
1675 return NULL;
1676
1677 ret = submodule_to_gitdir(&submodule_sb, submodule);
1678 if (ret) {
1679 strbuf_release(&submodule_sb);
1680 return NULL;
1681 }
1682
1683 /* assume that add_submodule_odb() has been called */
1684 refs = ref_store_init(submodule_sb.buf,
1685 REF_STORE_READ | REF_STORE_ODB);
1686 register_ref_store_map(&submodule_ref_stores, "submodule",
1687 refs, submodule);
1688
1689 strbuf_release(&submodule_sb);
1690 return refs;
1691 }
1692
1693 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1694 {
1695 struct ref_store *refs;
1696 const char *id;
1697
1698 if (wt->is_current)
1699 return get_main_ref_store();
1700
1701 id = wt->id ? wt->id : "/";
1702 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1703 if (refs)
1704 return refs;
1705
1706 if (wt->id)
1707 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1708 REF_STORE_ALL_CAPS);
1709 else
1710 refs = ref_store_init(get_git_common_dir(),
1711 REF_STORE_ALL_CAPS);
1712
1713 if (refs)
1714 register_ref_store_map(&worktree_ref_stores, "worktree",
1715 refs, id);
1716 return refs;
1717 }
1718
1719 void base_ref_store_init(struct ref_store *refs,
1720 const struct ref_storage_be *be)
1721 {
1722 refs->be = be;
1723 }
1724
1725 /* backend functions */
1726 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1727 {
1728 return refs->be->pack_refs(refs, flags);
1729 }
1730
1731 int refs_peel_ref(struct ref_store *refs, const char *refname,
1732 unsigned char *sha1)
1733 {
1734 return refs->be->peel_ref(refs, refname, sha1);
1735 }
1736
1737 int peel_ref(const char *refname, unsigned char *sha1)
1738 {
1739 return refs_peel_ref(get_main_ref_store(), refname, sha1);
1740 }
1741
1742 int refs_create_symref(struct ref_store *refs,
1743 const char *ref_target,
1744 const char *refs_heads_master,
1745 const char *logmsg)
1746 {
1747 return refs->be->create_symref(refs, ref_target,
1748 refs_heads_master,
1749 logmsg);
1750 }
1751
1752 int create_symref(const char *ref_target, const char *refs_heads_master,
1753 const char *logmsg)
1754 {
1755 return refs_create_symref(get_main_ref_store(), ref_target,
1756 refs_heads_master, logmsg);
1757 }
1758
1759 int ref_update_reject_duplicates(struct string_list *refnames,
1760 struct strbuf *err)
1761 {
1762 size_t i, n = refnames->nr;
1763
1764 assert(err);
1765
1766 for (i = 1; i < n; i++) {
1767 int cmp = strcmp(refnames->items[i - 1].string,
1768 refnames->items[i].string);
1769
1770 if (!cmp) {
1771 strbuf_addf(err,
1772 "multiple updates for ref '%s' not allowed.",
1773 refnames->items[i].string);
1774 return 1;
1775 } else if (cmp > 0) {
1776 die("BUG: ref_update_reject_duplicates() received unsorted list");
1777 }
1778 }
1779 return 0;
1780 }
1781
1782 int ref_transaction_prepare(struct ref_transaction *transaction,
1783 struct strbuf *err)
1784 {
1785 struct ref_store *refs = transaction->ref_store;
1786
1787 switch (transaction->state) {
1788 case REF_TRANSACTION_OPEN:
1789 /* Good. */
1790 break;
1791 case REF_TRANSACTION_PREPARED:
1792 die("BUG: prepare called twice on reference transaction");
1793 break;
1794 case REF_TRANSACTION_CLOSED:
1795 die("BUG: prepare called on a closed reference transaction");
1796 break;
1797 default:
1798 die("BUG: unexpected reference transaction state");
1799 break;
1800 }
1801
1802 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1803 strbuf_addstr(err,
1804 _("ref updates forbidden inside quarantine environment"));
1805 return -1;
1806 }
1807
1808 return refs->be->transaction_prepare(refs, transaction, err);
1809 }
1810
1811 int ref_transaction_abort(struct ref_transaction *transaction,
1812 struct strbuf *err)
1813 {
1814 struct ref_store *refs = transaction->ref_store;
1815 int ret = 0;
1816
1817 switch (transaction->state) {
1818 case REF_TRANSACTION_OPEN:
1819 /* No need to abort explicitly. */
1820 break;
1821 case REF_TRANSACTION_PREPARED:
1822 ret = refs->be->transaction_abort(refs, transaction, err);
1823 break;
1824 case REF_TRANSACTION_CLOSED:
1825 die("BUG: abort called on a closed reference transaction");
1826 break;
1827 default:
1828 die("BUG: unexpected reference transaction state");
1829 break;
1830 }
1831
1832 ref_transaction_free(transaction);
1833 return ret;
1834 }
1835
1836 int ref_transaction_commit(struct ref_transaction *transaction,
1837 struct strbuf *err)
1838 {
1839 struct ref_store *refs = transaction->ref_store;
1840 int ret;
1841
1842 switch (transaction->state) {
1843 case REF_TRANSACTION_OPEN:
1844 /* Need to prepare first. */
1845 ret = ref_transaction_prepare(transaction, err);
1846 if (ret)
1847 return ret;
1848 break;
1849 case REF_TRANSACTION_PREPARED:
1850 /* Fall through to finish. */
1851 break;
1852 case REF_TRANSACTION_CLOSED:
1853 die("BUG: commit called on a closed reference transaction");
1854 break;
1855 default:
1856 die("BUG: unexpected reference transaction state");
1857 break;
1858 }
1859
1860 return refs->be->transaction_finish(refs, transaction, err);
1861 }
1862
1863 int refs_verify_refname_available(struct ref_store *refs,
1864 const char *refname,
1865 const struct string_list *extras,
1866 const struct string_list *skip,
1867 struct strbuf *err)
1868 {
1869 const char *slash;
1870 const char *extra_refname;
1871 struct strbuf dirname = STRBUF_INIT;
1872 struct strbuf referent = STRBUF_INIT;
1873 struct object_id oid;
1874 unsigned int type;
1875 struct ref_iterator *iter;
1876 int ok;
1877 int ret = -1;
1878
1879 /*
1880 * For the sake of comments in this function, suppose that
1881 * refname is "refs/foo/bar".
1882 */
1883
1884 assert(err);
1885
1886 strbuf_grow(&dirname, strlen(refname) + 1);
1887 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1888 /* Expand dirname to the new prefix, not including the trailing slash: */
1889 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1890
1891 /*
1892 * We are still at a leading dir of the refname (e.g.,
1893 * "refs/foo"; if there is a reference with that name,
1894 * it is a conflict, *unless* it is in skip.
1895 */
1896 if (skip && string_list_has_string(skip, dirname.buf))
1897 continue;
1898
1899 if (!refs_read_raw_ref(refs, dirname.buf, oid.hash, &referent, &type)) {
1900 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1901 dirname.buf, refname);
1902 goto cleanup;
1903 }
1904
1905 if (extras && string_list_has_string(extras, dirname.buf)) {
1906 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1907 refname, dirname.buf);
1908 goto cleanup;
1909 }
1910 }
1911
1912 /*
1913 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1914 * There is no point in searching for a reference with that
1915 * name, because a refname isn't considered to conflict with
1916 * itself. But we still need to check for references whose
1917 * names are in the "refs/foo/bar/" namespace, because they
1918 * *do* conflict.
1919 */
1920 strbuf_addstr(&dirname, refname + dirname.len);
1921 strbuf_addch(&dirname, '/');
1922
1923 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
1924 DO_FOR_EACH_INCLUDE_BROKEN);
1925 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
1926 if (skip &&
1927 string_list_has_string(skip, iter->refname))
1928 continue;
1929
1930 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1931 iter->refname, refname);
1932 ref_iterator_abort(iter);
1933 goto cleanup;
1934 }
1935
1936 if (ok != ITER_DONE)
1937 die("BUG: error while iterating over references");
1938
1939 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
1940 if (extra_refname)
1941 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1942 refname, extra_refname);
1943 else
1944 ret = 0;
1945
1946 cleanup:
1947 strbuf_release(&referent);
1948 strbuf_release(&dirname);
1949 return ret;
1950 }
1951
1952 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1953 {
1954 struct ref_iterator *iter;
1955
1956 iter = refs->be->reflog_iterator_begin(refs);
1957
1958 return do_for_each_ref_iterator(iter, fn, cb_data);
1959 }
1960
1961 int for_each_reflog(each_ref_fn fn, void *cb_data)
1962 {
1963 return refs_for_each_reflog(get_main_ref_store(), fn, cb_data);
1964 }
1965
1966 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
1967 const char *refname,
1968 each_reflog_ent_fn fn,
1969 void *cb_data)
1970 {
1971 return refs->be->for_each_reflog_ent_reverse(refs, refname,
1972 fn, cb_data);
1973 }
1974
1975 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
1976 void *cb_data)
1977 {
1978 return refs_for_each_reflog_ent_reverse(get_main_ref_store(),
1979 refname, fn, cb_data);
1980 }
1981
1982 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
1983 each_reflog_ent_fn fn, void *cb_data)
1984 {
1985 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
1986 }
1987
1988 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
1989 void *cb_data)
1990 {
1991 return refs_for_each_reflog_ent(get_main_ref_store(), refname,
1992 fn, cb_data);
1993 }
1994
1995 int refs_reflog_exists(struct ref_store *refs, const char *refname)
1996 {
1997 return refs->be->reflog_exists(refs, refname);
1998 }
1999
2000 int reflog_exists(const char *refname)
2001 {
2002 return refs_reflog_exists(get_main_ref_store(), refname);
2003 }
2004
2005 int refs_create_reflog(struct ref_store *refs, const char *refname,
2006 int force_create, struct strbuf *err)
2007 {
2008 return refs->be->create_reflog(refs, refname, force_create, err);
2009 }
2010
2011 int safe_create_reflog(const char *refname, int force_create,
2012 struct strbuf *err)
2013 {
2014 return refs_create_reflog(get_main_ref_store(), refname,
2015 force_create, err);
2016 }
2017
2018 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2019 {
2020 return refs->be->delete_reflog(refs, refname);
2021 }
2022
2023 int delete_reflog(const char *refname)
2024 {
2025 return refs_delete_reflog(get_main_ref_store(), refname);
2026 }
2027
2028 int refs_reflog_expire(struct ref_store *refs,
2029 const char *refname, const unsigned char *sha1,
2030 unsigned int flags,
2031 reflog_expiry_prepare_fn prepare_fn,
2032 reflog_expiry_should_prune_fn should_prune_fn,
2033 reflog_expiry_cleanup_fn cleanup_fn,
2034 void *policy_cb_data)
2035 {
2036 return refs->be->reflog_expire(refs, refname, sha1, flags,
2037 prepare_fn, should_prune_fn,
2038 cleanup_fn, policy_cb_data);
2039 }
2040
2041 int reflog_expire(const char *refname, const unsigned char *sha1,
2042 unsigned int flags,
2043 reflog_expiry_prepare_fn prepare_fn,
2044 reflog_expiry_should_prune_fn should_prune_fn,
2045 reflog_expiry_cleanup_fn cleanup_fn,
2046 void *policy_cb_data)
2047 {
2048 return refs_reflog_expire(get_main_ref_store(),
2049 refname, sha1, flags,
2050 prepare_fn, should_prune_fn,
2051 cleanup_fn, policy_cb_data);
2052 }
2053
2054 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2055 struct strbuf *err)
2056 {
2057 struct ref_store *refs = transaction->ref_store;
2058
2059 return refs->be->initial_transaction_commit(refs, transaction, err);
2060 }
2061
2062 int refs_delete_refs(struct ref_store *refs, const char *msg,
2063 struct string_list *refnames, unsigned int flags)
2064 {
2065 return refs->be->delete_refs(refs, msg, refnames, flags);
2066 }
2067
2068 int delete_refs(const char *msg, struct string_list *refnames,
2069 unsigned int flags)
2070 {
2071 return refs_delete_refs(get_main_ref_store(), msg, refnames, flags);
2072 }
2073
2074 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2075 const char *newref, const char *logmsg)
2076 {
2077 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2078 }
2079
2080 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2081 {
2082 return refs_rename_ref(get_main_ref_store(), oldref, newref, logmsg);
2083 }