refs: convert delete_ref and refs_delete_ref to struct object_id
[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 return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, NULL, NULL);
243 }
244
245 static int filter_refs(const char *refname, const struct object_id *oid,
246 int flags, void *data)
247 {
248 struct ref_filter *filter = (struct ref_filter *)data;
249
250 if (wildmatch(filter->pattern, refname, 0))
251 return 0;
252 return filter->fn(refname, oid, flags, filter->cb_data);
253 }
254
255 enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
256 {
257 struct object *o = lookup_unknown_object(name);
258
259 if (o->type == OBJ_NONE) {
260 int type = sha1_object_info(name, NULL);
261 if (type < 0 || !object_as_type(o, type, 0))
262 return PEEL_INVALID;
263 }
264
265 if (o->type != OBJ_TAG)
266 return PEEL_NON_TAG;
267
268 o = deref_tag_noverify(o);
269 if (!o)
270 return PEEL_INVALID;
271
272 hashcpy(sha1, o->oid.hash);
273 return PEEL_PEELED;
274 }
275
276 struct warn_if_dangling_data {
277 FILE *fp;
278 const char *refname;
279 const struct string_list *refnames;
280 const char *msg_fmt;
281 };
282
283 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
284 int flags, void *cb_data)
285 {
286 struct warn_if_dangling_data *d = cb_data;
287 const char *resolves_to;
288
289 if (!(flags & REF_ISSYMREF))
290 return 0;
291
292 resolves_to = resolve_ref_unsafe(refname, 0, NULL, NULL);
293 if (!resolves_to
294 || (d->refname
295 ? strcmp(resolves_to, d->refname)
296 : !string_list_has_string(d->refnames, resolves_to))) {
297 return 0;
298 }
299
300 fprintf(d->fp, d->msg_fmt, refname);
301 fputc('\n', d->fp);
302 return 0;
303 }
304
305 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
306 {
307 struct warn_if_dangling_data data;
308
309 data.fp = fp;
310 data.refname = refname;
311 data.refnames = NULL;
312 data.msg_fmt = msg_fmt;
313 for_each_rawref(warn_if_dangling_symref, &data);
314 }
315
316 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
317 {
318 struct warn_if_dangling_data data;
319
320 data.fp = fp;
321 data.refname = NULL;
322 data.refnames = refnames;
323 data.msg_fmt = msg_fmt;
324 for_each_rawref(warn_if_dangling_symref, &data);
325 }
326
327 int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
328 {
329 return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
330 }
331
332 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
333 {
334 return refs_for_each_tag_ref(get_main_ref_store(), fn, cb_data);
335 }
336
337 int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
338 {
339 return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
340 }
341
342 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
343 {
344 return refs_for_each_branch_ref(get_main_ref_store(), fn, cb_data);
345 }
346
347 int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
348 {
349 return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
350 }
351
352 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
353 {
354 return refs_for_each_remote_ref(get_main_ref_store(), fn, cb_data);
355 }
356
357 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
358 {
359 struct strbuf buf = STRBUF_INIT;
360 int ret = 0;
361 struct object_id oid;
362 int flag;
363
364 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
365 if (!read_ref_full(buf.buf, RESOLVE_REF_READING, oid.hash, &flag))
366 ret = fn(buf.buf, &oid, flag, cb_data);
367 strbuf_release(&buf);
368
369 return ret;
370 }
371
372 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
373 const char *prefix, void *cb_data)
374 {
375 struct strbuf real_pattern = STRBUF_INIT;
376 struct ref_filter filter;
377 int ret;
378
379 if (!prefix && !starts_with(pattern, "refs/"))
380 strbuf_addstr(&real_pattern, "refs/");
381 else if (prefix)
382 strbuf_addstr(&real_pattern, prefix);
383 strbuf_addstr(&real_pattern, pattern);
384
385 if (!has_glob_specials(pattern)) {
386 /* Append implied '/' '*' if not present. */
387 strbuf_complete(&real_pattern, '/');
388 /* No need to check for '*', there is none. */
389 strbuf_addch(&real_pattern, '*');
390 }
391
392 filter.pattern = real_pattern.buf;
393 filter.fn = fn;
394 filter.cb_data = cb_data;
395 ret = for_each_ref(filter_refs, &filter);
396
397 strbuf_release(&real_pattern);
398 return ret;
399 }
400
401 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
402 {
403 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
404 }
405
406 const char *prettify_refname(const char *name)
407 {
408 if (skip_prefix(name, "refs/heads/", &name) ||
409 skip_prefix(name, "refs/tags/", &name) ||
410 skip_prefix(name, "refs/remotes/", &name))
411 ; /* nothing */
412 return name;
413 }
414
415 static const char *ref_rev_parse_rules[] = {
416 "%.*s",
417 "refs/%.*s",
418 "refs/tags/%.*s",
419 "refs/heads/%.*s",
420 "refs/remotes/%.*s",
421 "refs/remotes/%.*s/HEAD",
422 NULL
423 };
424
425 int refname_match(const char *abbrev_name, const char *full_name)
426 {
427 const char **p;
428 const int abbrev_name_len = strlen(abbrev_name);
429
430 for (p = ref_rev_parse_rules; *p; p++) {
431 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
432 return 1;
433 }
434 }
435
436 return 0;
437 }
438
439 /*
440 * *string and *len will only be substituted, and *string returned (for
441 * later free()ing) if the string passed in is a magic short-hand form
442 * to name a branch.
443 */
444 static char *substitute_branch_name(const char **string, int *len)
445 {
446 struct strbuf buf = STRBUF_INIT;
447 int ret = interpret_branch_name(*string, *len, &buf, 0);
448
449 if (ret == *len) {
450 size_t size;
451 *string = strbuf_detach(&buf, &size);
452 *len = size;
453 return (char *)*string;
454 }
455
456 return NULL;
457 }
458
459 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
460 {
461 char *last_branch = substitute_branch_name(&str, &len);
462 int refs_found = expand_ref(str, len, sha1, ref);
463 free(last_branch);
464 return refs_found;
465 }
466
467 int expand_ref(const char *str, int len, unsigned char *sha1, char **ref)
468 {
469 const char **p, *r;
470 int refs_found = 0;
471 struct strbuf fullref = STRBUF_INIT;
472
473 *ref = NULL;
474 for (p = ref_rev_parse_rules; *p; p++) {
475 unsigned char sha1_from_ref[20];
476 unsigned char *this_result;
477 int flag;
478
479 this_result = refs_found ? sha1_from_ref : sha1;
480 strbuf_reset(&fullref);
481 strbuf_addf(&fullref, *p, len, str);
482 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
483 this_result, &flag);
484 if (r) {
485 if (!refs_found++)
486 *ref = xstrdup(r);
487 if (!warn_ambiguous_refs)
488 break;
489 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
490 warning("ignoring dangling symref %s.", fullref.buf);
491 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
492 warning("ignoring broken ref %s.", fullref.buf);
493 }
494 }
495 strbuf_release(&fullref);
496 return refs_found;
497 }
498
499 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
500 {
501 char *last_branch = substitute_branch_name(&str, &len);
502 const char **p;
503 int logs_found = 0;
504 struct strbuf path = STRBUF_INIT;
505
506 *log = NULL;
507 for (p = ref_rev_parse_rules; *p; p++) {
508 unsigned char hash[20];
509 const char *ref, *it;
510
511 strbuf_reset(&path);
512 strbuf_addf(&path, *p, len, str);
513 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
514 hash, NULL);
515 if (!ref)
516 continue;
517 if (reflog_exists(path.buf))
518 it = path.buf;
519 else if (strcmp(ref, path.buf) && reflog_exists(ref))
520 it = ref;
521 else
522 continue;
523 if (!logs_found++) {
524 *log = xstrdup(it);
525 hashcpy(sha1, hash);
526 }
527 if (!warn_ambiguous_refs)
528 break;
529 }
530 strbuf_release(&path);
531 free(last_branch);
532 return logs_found;
533 }
534
535 static int is_per_worktree_ref(const char *refname)
536 {
537 return !strcmp(refname, "HEAD") ||
538 starts_with(refname, "refs/bisect/");
539 }
540
541 static int is_pseudoref_syntax(const char *refname)
542 {
543 const char *c;
544
545 for (c = refname; *c; c++) {
546 if (!isupper(*c) && *c != '-' && *c != '_')
547 return 0;
548 }
549
550 return 1;
551 }
552
553 enum ref_type ref_type(const char *refname)
554 {
555 if (is_per_worktree_ref(refname))
556 return REF_TYPE_PER_WORKTREE;
557 if (is_pseudoref_syntax(refname))
558 return REF_TYPE_PSEUDOREF;
559 return REF_TYPE_NORMAL;
560 }
561
562 long get_files_ref_lock_timeout_ms(void)
563 {
564 static int configured = 0;
565
566 /* The default timeout is 100 ms: */
567 static int timeout_ms = 100;
568
569 if (!configured) {
570 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
571 configured = 1;
572 }
573
574 return timeout_ms;
575 }
576
577 static int write_pseudoref(const char *pseudoref, const unsigned char *sha1,
578 const unsigned char *old_sha1, struct strbuf *err)
579 {
580 const char *filename;
581 int fd;
582 static struct lock_file lock;
583 struct strbuf buf = STRBUF_INIT;
584 int ret = -1;
585
586 strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
587
588 filename = git_path("%s", pseudoref);
589 fd = hold_lock_file_for_update_timeout(&lock, filename,
590 LOCK_DIE_ON_ERROR,
591 get_files_ref_lock_timeout_ms());
592 if (fd < 0) {
593 strbuf_addf(err, "could not open '%s' for writing: %s",
594 filename, strerror(errno));
595 goto done;
596 }
597
598 if (old_sha1) {
599 unsigned char actual_old_sha1[20];
600
601 if (read_ref(pseudoref, actual_old_sha1))
602 die("could not read ref '%s'", pseudoref);
603 if (hashcmp(actual_old_sha1, old_sha1)) {
604 strbuf_addf(err, "unexpected sha1 when writing '%s'", pseudoref);
605 rollback_lock_file(&lock);
606 goto done;
607 }
608 }
609
610 if (write_in_full(fd, buf.buf, buf.len) < 0) {
611 strbuf_addf(err, "could not write to '%s'", filename);
612 rollback_lock_file(&lock);
613 goto done;
614 }
615
616 commit_lock_file(&lock);
617 ret = 0;
618 done:
619 strbuf_release(&buf);
620 return ret;
621 }
622
623 static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
624 {
625 static struct lock_file lock;
626 const char *filename;
627
628 filename = git_path("%s", pseudoref);
629
630 if (old_oid && !is_null_oid(old_oid)) {
631 int fd;
632 struct object_id actual_old_oid;
633
634 fd = hold_lock_file_for_update_timeout(
635 &lock, filename, LOCK_DIE_ON_ERROR,
636 get_files_ref_lock_timeout_ms());
637 if (fd < 0)
638 die_errno(_("Could not open '%s' for writing"), filename);
639 if (read_ref(pseudoref, actual_old_oid.hash))
640 die("could not read ref '%s'", pseudoref);
641 if (oidcmp(&actual_old_oid, old_oid)) {
642 warning("Unexpected sha1 when deleting %s", pseudoref);
643 rollback_lock_file(&lock);
644 return -1;
645 }
646
647 unlink(filename);
648 rollback_lock_file(&lock);
649 } else {
650 unlink(filename);
651 }
652
653 return 0;
654 }
655
656 int refs_delete_ref(struct ref_store *refs, const char *msg,
657 const char *refname,
658 const struct object_id *old_oid,
659 unsigned int flags)
660 {
661 struct ref_transaction *transaction;
662 struct strbuf err = STRBUF_INIT;
663
664 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
665 assert(refs == get_main_ref_store());
666 return delete_pseudoref(refname, old_oid);
667 }
668
669 transaction = ref_store_transaction_begin(refs, &err);
670 if (!transaction ||
671 ref_transaction_delete(transaction, refname,
672 old_oid ? old_oid->hash : NULL,
673 flags, msg, &err) ||
674 ref_transaction_commit(transaction, &err)) {
675 error("%s", err.buf);
676 ref_transaction_free(transaction);
677 strbuf_release(&err);
678 return 1;
679 }
680 ref_transaction_free(transaction);
681 strbuf_release(&err);
682 return 0;
683 }
684
685 int delete_ref(const char *msg, const char *refname,
686 const struct object_id *old_oid, unsigned int flags)
687 {
688 return refs_delete_ref(get_main_ref_store(), msg, refname,
689 old_oid, flags);
690 }
691
692 int copy_reflog_msg(char *buf, const char *msg)
693 {
694 char *cp = buf;
695 char c;
696 int wasspace = 1;
697
698 *cp++ = '\t';
699 while ((c = *msg++)) {
700 if (wasspace && isspace(c))
701 continue;
702 wasspace = isspace(c);
703 if (wasspace)
704 c = ' ';
705 *cp++ = c;
706 }
707 while (buf < cp && isspace(cp[-1]))
708 cp--;
709 *cp++ = '\n';
710 return cp - buf;
711 }
712
713 int should_autocreate_reflog(const char *refname)
714 {
715 switch (log_all_ref_updates) {
716 case LOG_REFS_ALWAYS:
717 return 1;
718 case LOG_REFS_NORMAL:
719 return starts_with(refname, "refs/heads/") ||
720 starts_with(refname, "refs/remotes/") ||
721 starts_with(refname, "refs/notes/") ||
722 !strcmp(refname, "HEAD");
723 default:
724 return 0;
725 }
726 }
727
728 int is_branch(const char *refname)
729 {
730 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
731 }
732
733 struct read_ref_at_cb {
734 const char *refname;
735 timestamp_t at_time;
736 int cnt;
737 int reccnt;
738 unsigned char *sha1;
739 int found_it;
740
741 unsigned char osha1[20];
742 unsigned char nsha1[20];
743 int tz;
744 timestamp_t date;
745 char **msg;
746 timestamp_t *cutoff_time;
747 int *cutoff_tz;
748 int *cutoff_cnt;
749 };
750
751 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
752 const char *email, timestamp_t timestamp, int tz,
753 const char *message, void *cb_data)
754 {
755 struct read_ref_at_cb *cb = cb_data;
756
757 cb->reccnt++;
758 cb->tz = tz;
759 cb->date = timestamp;
760
761 if (timestamp <= cb->at_time || cb->cnt == 0) {
762 if (cb->msg)
763 *cb->msg = xstrdup(message);
764 if (cb->cutoff_time)
765 *cb->cutoff_time = timestamp;
766 if (cb->cutoff_tz)
767 *cb->cutoff_tz = tz;
768 if (cb->cutoff_cnt)
769 *cb->cutoff_cnt = cb->reccnt - 1;
770 /*
771 * we have not yet updated cb->[n|o]sha1 so they still
772 * hold the values for the previous record.
773 */
774 if (!is_null_sha1(cb->osha1)) {
775 hashcpy(cb->sha1, noid->hash);
776 if (hashcmp(cb->osha1, noid->hash))
777 warning("Log for ref %s has gap after %s.",
778 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
779 }
780 else if (cb->date == cb->at_time)
781 hashcpy(cb->sha1, noid->hash);
782 else if (hashcmp(noid->hash, cb->sha1))
783 warning("Log for ref %s unexpectedly ended on %s.",
784 cb->refname, show_date(cb->date, cb->tz,
785 DATE_MODE(RFC2822)));
786 hashcpy(cb->osha1, ooid->hash);
787 hashcpy(cb->nsha1, noid->hash);
788 cb->found_it = 1;
789 return 1;
790 }
791 hashcpy(cb->osha1, ooid->hash);
792 hashcpy(cb->nsha1, noid->hash);
793 if (cb->cnt > 0)
794 cb->cnt--;
795 return 0;
796 }
797
798 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
799 const char *email, timestamp_t timestamp,
800 int tz, const char *message, void *cb_data)
801 {
802 struct read_ref_at_cb *cb = cb_data;
803
804 if (cb->msg)
805 *cb->msg = xstrdup(message);
806 if (cb->cutoff_time)
807 *cb->cutoff_time = timestamp;
808 if (cb->cutoff_tz)
809 *cb->cutoff_tz = tz;
810 if (cb->cutoff_cnt)
811 *cb->cutoff_cnt = cb->reccnt;
812 hashcpy(cb->sha1, ooid->hash);
813 if (is_null_sha1(cb->sha1))
814 hashcpy(cb->sha1, noid->hash);
815 /* We just want the first entry */
816 return 1;
817 }
818
819 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
820 unsigned char *sha1, char **msg,
821 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
822 {
823 struct read_ref_at_cb cb;
824
825 memset(&cb, 0, sizeof(cb));
826 cb.refname = refname;
827 cb.at_time = at_time;
828 cb.cnt = cnt;
829 cb.msg = msg;
830 cb.cutoff_time = cutoff_time;
831 cb.cutoff_tz = cutoff_tz;
832 cb.cutoff_cnt = cutoff_cnt;
833 cb.sha1 = sha1;
834
835 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
836
837 if (!cb.reccnt) {
838 if (flags & GET_OID_QUIETLY)
839 exit(128);
840 else
841 die("Log for %s is empty.", refname);
842 }
843 if (cb.found_it)
844 return 0;
845
846 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
847
848 return 1;
849 }
850
851 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
852 struct strbuf *err)
853 {
854 struct ref_transaction *tr;
855 assert(err);
856
857 tr = xcalloc(1, sizeof(struct ref_transaction));
858 tr->ref_store = refs;
859 return tr;
860 }
861
862 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
863 {
864 return ref_store_transaction_begin(get_main_ref_store(), err);
865 }
866
867 void ref_transaction_free(struct ref_transaction *transaction)
868 {
869 size_t i;
870
871 if (!transaction)
872 return;
873
874 switch (transaction->state) {
875 case REF_TRANSACTION_OPEN:
876 case REF_TRANSACTION_CLOSED:
877 /* OK */
878 break;
879 case REF_TRANSACTION_PREPARED:
880 die("BUG: free called on a prepared reference transaction");
881 break;
882 default:
883 die("BUG: unexpected reference transaction state");
884 break;
885 }
886
887 for (i = 0; i < transaction->nr; i++) {
888 free(transaction->updates[i]->msg);
889 free(transaction->updates[i]);
890 }
891 free(transaction->updates);
892 free(transaction);
893 }
894
895 struct ref_update *ref_transaction_add_update(
896 struct ref_transaction *transaction,
897 const char *refname, unsigned int flags,
898 const unsigned char *new_sha1,
899 const unsigned char *old_sha1,
900 const char *msg)
901 {
902 struct ref_update *update;
903
904 if (transaction->state != REF_TRANSACTION_OPEN)
905 die("BUG: update called for transaction that is not open");
906
907 if ((flags & REF_ISPRUNING) && !(flags & REF_NODEREF))
908 die("BUG: REF_ISPRUNING set without REF_NODEREF");
909
910 FLEX_ALLOC_STR(update, refname, refname);
911 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
912 transaction->updates[transaction->nr++] = update;
913
914 update->flags = flags;
915
916 if (flags & REF_HAVE_NEW)
917 hashcpy(update->new_oid.hash, new_sha1);
918 if (flags & REF_HAVE_OLD)
919 hashcpy(update->old_oid.hash, old_sha1);
920 update->msg = xstrdup_or_null(msg);
921 return update;
922 }
923
924 int ref_transaction_update(struct ref_transaction *transaction,
925 const char *refname,
926 const unsigned char *new_sha1,
927 const unsigned char *old_sha1,
928 unsigned int flags, const char *msg,
929 struct strbuf *err)
930 {
931 assert(err);
932
933 if ((new_sha1 && !is_null_sha1(new_sha1)) ?
934 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
935 !refname_is_safe(refname)) {
936 strbuf_addf(err, "refusing to update ref with bad name '%s'",
937 refname);
938 return -1;
939 }
940
941 flags &= REF_TRANSACTION_UPDATE_ALLOWED_FLAGS;
942
943 flags |= (new_sha1 ? REF_HAVE_NEW : 0) | (old_sha1 ? REF_HAVE_OLD : 0);
944
945 ref_transaction_add_update(transaction, refname, flags,
946 new_sha1, old_sha1, msg);
947 return 0;
948 }
949
950 int ref_transaction_create(struct ref_transaction *transaction,
951 const char *refname,
952 const unsigned char *new_sha1,
953 unsigned int flags, const char *msg,
954 struct strbuf *err)
955 {
956 if (!new_sha1 || is_null_sha1(new_sha1))
957 die("BUG: create called without valid new_sha1");
958 return ref_transaction_update(transaction, refname, new_sha1,
959 null_sha1, flags, msg, err);
960 }
961
962 int ref_transaction_delete(struct ref_transaction *transaction,
963 const char *refname,
964 const unsigned char *old_sha1,
965 unsigned int flags, const char *msg,
966 struct strbuf *err)
967 {
968 if (old_sha1 && is_null_sha1(old_sha1))
969 die("BUG: delete called with old_sha1 set to zeros");
970 return ref_transaction_update(transaction, refname,
971 null_sha1, old_sha1,
972 flags, msg, err);
973 }
974
975 int ref_transaction_verify(struct ref_transaction *transaction,
976 const char *refname,
977 const unsigned char *old_sha1,
978 unsigned int flags,
979 struct strbuf *err)
980 {
981 if (!old_sha1)
982 die("BUG: verify called with old_sha1 set to NULL");
983 return ref_transaction_update(transaction, refname,
984 NULL, old_sha1,
985 flags, NULL, err);
986 }
987
988 int update_ref_oid(const char *msg, const char *refname,
989 const struct object_id *new_oid, const struct object_id *old_oid,
990 unsigned int flags, enum action_on_err onerr)
991 {
992 return update_ref(msg, refname, new_oid ? new_oid->hash : NULL,
993 old_oid ? old_oid->hash : NULL, flags, onerr);
994 }
995
996 int refs_update_ref(struct ref_store *refs, const char *msg,
997 const char *refname, const unsigned char *new_sha1,
998 const unsigned char *old_sha1, unsigned int flags,
999 enum action_on_err onerr)
1000 {
1001 struct ref_transaction *t = NULL;
1002 struct strbuf err = STRBUF_INIT;
1003 int ret = 0;
1004
1005 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1006 assert(refs == get_main_ref_store());
1007 ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
1008 } else {
1009 t = ref_store_transaction_begin(refs, &err);
1010 if (!t ||
1011 ref_transaction_update(t, refname, new_sha1, old_sha1,
1012 flags, msg, &err) ||
1013 ref_transaction_commit(t, &err)) {
1014 ret = 1;
1015 ref_transaction_free(t);
1016 }
1017 }
1018 if (ret) {
1019 const char *str = "update_ref failed for ref '%s': %s";
1020
1021 switch (onerr) {
1022 case UPDATE_REFS_MSG_ON_ERR:
1023 error(str, refname, err.buf);
1024 break;
1025 case UPDATE_REFS_DIE_ON_ERR:
1026 die(str, refname, err.buf);
1027 break;
1028 case UPDATE_REFS_QUIET_ON_ERR:
1029 break;
1030 }
1031 strbuf_release(&err);
1032 return 1;
1033 }
1034 strbuf_release(&err);
1035 if (t)
1036 ref_transaction_free(t);
1037 return 0;
1038 }
1039
1040 int update_ref(const char *msg, const char *refname,
1041 const unsigned char *new_sha1,
1042 const unsigned char *old_sha1,
1043 unsigned int flags, enum action_on_err onerr)
1044 {
1045 return refs_update_ref(get_main_ref_store(), msg, refname, new_sha1,
1046 old_sha1, flags, onerr);
1047 }
1048
1049 char *shorten_unambiguous_ref(const char *refname, int strict)
1050 {
1051 int i;
1052 static char **scanf_fmts;
1053 static int nr_rules;
1054 char *short_name;
1055 struct strbuf resolved_buf = STRBUF_INIT;
1056
1057 if (!nr_rules) {
1058 /*
1059 * Pre-generate scanf formats from ref_rev_parse_rules[].
1060 * Generate a format suitable for scanf from a
1061 * ref_rev_parse_rules rule by interpolating "%s" at the
1062 * location of the "%.*s".
1063 */
1064 size_t total_len = 0;
1065 size_t offset = 0;
1066
1067 /* the rule list is NULL terminated, count them first */
1068 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1069 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1070 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1071
1072 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1073
1074 offset = 0;
1075 for (i = 0; i < nr_rules; i++) {
1076 assert(offset < total_len);
1077 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1078 offset += snprintf(scanf_fmts[i], total_len - offset,
1079 ref_rev_parse_rules[i], 2, "%s") + 1;
1080 }
1081 }
1082
1083 /* bail out if there are no rules */
1084 if (!nr_rules)
1085 return xstrdup(refname);
1086
1087 /* buffer for scanf result, at most refname must fit */
1088 short_name = xstrdup(refname);
1089
1090 /* skip first rule, it will always match */
1091 for (i = nr_rules - 1; i > 0 ; --i) {
1092 int j;
1093 int rules_to_fail = i;
1094 int short_name_len;
1095
1096 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1097 continue;
1098
1099 short_name_len = strlen(short_name);
1100
1101 /*
1102 * in strict mode, all (except the matched one) rules
1103 * must fail to resolve to a valid non-ambiguous ref
1104 */
1105 if (strict)
1106 rules_to_fail = nr_rules;
1107
1108 /*
1109 * check if the short name resolves to a valid ref,
1110 * but use only rules prior to the matched one
1111 */
1112 for (j = 0; j < rules_to_fail; j++) {
1113 const char *rule = ref_rev_parse_rules[j];
1114
1115 /* skip matched rule */
1116 if (i == j)
1117 continue;
1118
1119 /*
1120 * the short name is ambiguous, if it resolves
1121 * (with this previous rule) to a valid ref
1122 * read_ref() returns 0 on success
1123 */
1124 strbuf_reset(&resolved_buf);
1125 strbuf_addf(&resolved_buf, rule,
1126 short_name_len, short_name);
1127 if (ref_exists(resolved_buf.buf))
1128 break;
1129 }
1130
1131 /*
1132 * short name is non-ambiguous if all previous rules
1133 * haven't resolved to a valid ref
1134 */
1135 if (j == rules_to_fail) {
1136 strbuf_release(&resolved_buf);
1137 return short_name;
1138 }
1139 }
1140
1141 strbuf_release(&resolved_buf);
1142 free(short_name);
1143 return xstrdup(refname);
1144 }
1145
1146 static struct string_list *hide_refs;
1147
1148 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1149 {
1150 const char *key;
1151 if (!strcmp("transfer.hiderefs", var) ||
1152 (!parse_config_key(var, section, NULL, NULL, &key) &&
1153 !strcmp(key, "hiderefs"))) {
1154 char *ref;
1155 int len;
1156
1157 if (!value)
1158 return config_error_nonbool(var);
1159 ref = xstrdup(value);
1160 len = strlen(ref);
1161 while (len && ref[len - 1] == '/')
1162 ref[--len] = '\0';
1163 if (!hide_refs) {
1164 hide_refs = xcalloc(1, sizeof(*hide_refs));
1165 hide_refs->strdup_strings = 1;
1166 }
1167 string_list_append(hide_refs, ref);
1168 }
1169 return 0;
1170 }
1171
1172 int ref_is_hidden(const char *refname, const char *refname_full)
1173 {
1174 int i;
1175
1176 if (!hide_refs)
1177 return 0;
1178 for (i = hide_refs->nr - 1; i >= 0; i--) {
1179 const char *match = hide_refs->items[i].string;
1180 const char *subject;
1181 int neg = 0;
1182 const char *p;
1183
1184 if (*match == '!') {
1185 neg = 1;
1186 match++;
1187 }
1188
1189 if (*match == '^') {
1190 subject = refname_full;
1191 match++;
1192 } else {
1193 subject = refname;
1194 }
1195
1196 /* refname can be NULL when namespaces are used. */
1197 if (subject &&
1198 skip_prefix(subject, match, &p) &&
1199 (!*p || *p == '/'))
1200 return !neg;
1201 }
1202 return 0;
1203 }
1204
1205 const char *find_descendant_ref(const char *dirname,
1206 const struct string_list *extras,
1207 const struct string_list *skip)
1208 {
1209 int pos;
1210
1211 if (!extras)
1212 return NULL;
1213
1214 /*
1215 * Look at the place where dirname would be inserted into
1216 * extras. If there is an entry at that position that starts
1217 * with dirname (remember, dirname includes the trailing
1218 * slash) and is not in skip, then we have a conflict.
1219 */
1220 for (pos = string_list_find_insert_index(extras, dirname, 0);
1221 pos < extras->nr; pos++) {
1222 const char *extra_refname = extras->items[pos].string;
1223
1224 if (!starts_with(extra_refname, dirname))
1225 break;
1226
1227 if (!skip || !string_list_has_string(skip, extra_refname))
1228 return extra_refname;
1229 }
1230 return NULL;
1231 }
1232
1233 int refs_rename_ref_available(struct ref_store *refs,
1234 const char *old_refname,
1235 const char *new_refname)
1236 {
1237 struct string_list skip = STRING_LIST_INIT_NODUP;
1238 struct strbuf err = STRBUF_INIT;
1239 int ok;
1240
1241 string_list_insert(&skip, old_refname);
1242 ok = !refs_verify_refname_available(refs, new_refname,
1243 NULL, &skip, &err);
1244 if (!ok)
1245 error("%s", err.buf);
1246
1247 string_list_clear(&skip, 0);
1248 strbuf_release(&err);
1249 return ok;
1250 }
1251
1252 int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1253 {
1254 struct object_id oid;
1255 int flag;
1256
1257 if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1258 oid.hash, &flag))
1259 return fn("HEAD", &oid, flag, cb_data);
1260
1261 return 0;
1262 }
1263
1264 int head_ref(each_ref_fn fn, void *cb_data)
1265 {
1266 return refs_head_ref(get_main_ref_store(), fn, cb_data);
1267 }
1268
1269 struct ref_iterator *refs_ref_iterator_begin(
1270 struct ref_store *refs,
1271 const char *prefix, int trim, int flags)
1272 {
1273 struct ref_iterator *iter;
1274
1275 if (ref_paranoia < 0)
1276 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1277 if (ref_paranoia)
1278 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1279
1280 iter = refs->be->iterator_begin(refs, prefix, flags);
1281
1282 /*
1283 * `iterator_begin()` already takes care of prefix, but we
1284 * might need to do some trimming:
1285 */
1286 if (trim)
1287 iter = prefix_ref_iterator_begin(iter, "", trim);
1288
1289 /* Sanity check for subclasses: */
1290 if (!iter->ordered)
1291 BUG("reference iterator is not ordered");
1292
1293 return iter;
1294 }
1295
1296 /*
1297 * Call fn for each reference in the specified submodule for which the
1298 * refname begins with prefix. If trim is non-zero, then trim that
1299 * many characters off the beginning of each refname before passing
1300 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1301 * include broken references in the iteration. If fn ever returns a
1302 * non-zero value, stop the iteration and return that value;
1303 * otherwise, return 0.
1304 */
1305 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1306 each_ref_fn fn, int trim, int flags, void *cb_data)
1307 {
1308 struct ref_iterator *iter;
1309
1310 if (!refs)
1311 return 0;
1312
1313 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1314
1315 return do_for_each_ref_iterator(iter, fn, cb_data);
1316 }
1317
1318 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1319 {
1320 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1321 }
1322
1323 int for_each_ref(each_ref_fn fn, void *cb_data)
1324 {
1325 return refs_for_each_ref(get_main_ref_store(), fn, cb_data);
1326 }
1327
1328 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1329 each_ref_fn fn, void *cb_data)
1330 {
1331 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1332 }
1333
1334 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1335 {
1336 return refs_for_each_ref_in(get_main_ref_store(), prefix, fn, cb_data);
1337 }
1338
1339 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1340 {
1341 unsigned int flag = 0;
1342
1343 if (broken)
1344 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1345 return do_for_each_ref(get_main_ref_store(),
1346 prefix, fn, 0, flag, cb_data);
1347 }
1348
1349 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1350 each_ref_fn fn, void *cb_data,
1351 unsigned int broken)
1352 {
1353 unsigned int flag = 0;
1354
1355 if (broken)
1356 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1357 return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1358 }
1359
1360 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1361 {
1362 return do_for_each_ref(get_main_ref_store(),
1363 git_replace_ref_base, fn,
1364 strlen(git_replace_ref_base),
1365 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1366 }
1367
1368 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1369 {
1370 struct strbuf buf = STRBUF_INIT;
1371 int ret;
1372 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1373 ret = do_for_each_ref(get_main_ref_store(),
1374 buf.buf, fn, 0, 0, cb_data);
1375 strbuf_release(&buf);
1376 return ret;
1377 }
1378
1379 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1380 {
1381 return do_for_each_ref(refs, "", fn, 0,
1382 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1383 }
1384
1385 int for_each_rawref(each_ref_fn fn, void *cb_data)
1386 {
1387 return refs_for_each_rawref(get_main_ref_store(), fn, cb_data);
1388 }
1389
1390 int refs_read_raw_ref(struct ref_store *ref_store,
1391 const char *refname, unsigned char *sha1,
1392 struct strbuf *referent, unsigned int *type)
1393 {
1394 return ref_store->be->read_raw_ref(ref_store, refname, sha1, referent, type);
1395 }
1396
1397 /* This function needs to return a meaningful errno on failure */
1398 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1399 const char *refname,
1400 int resolve_flags,
1401 unsigned char *sha1, int *flags)
1402 {
1403 static struct strbuf sb_refname = STRBUF_INIT;
1404 struct object_id unused_oid;
1405 int unused_flags;
1406 int symref_count;
1407
1408 if (!sha1)
1409 sha1 = unused_oid.hash;
1410 if (!flags)
1411 flags = &unused_flags;
1412
1413 *flags = 0;
1414
1415 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1416 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1417 !refname_is_safe(refname)) {
1418 errno = EINVAL;
1419 return NULL;
1420 }
1421
1422 /*
1423 * dwim_ref() uses REF_ISBROKEN to distinguish between
1424 * missing refs and refs that were present but invalid,
1425 * to complain about the latter to stderr.
1426 *
1427 * We don't know whether the ref exists, so don't set
1428 * REF_ISBROKEN yet.
1429 */
1430 *flags |= REF_BAD_NAME;
1431 }
1432
1433 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1434 unsigned int read_flags = 0;
1435
1436 if (refs_read_raw_ref(refs, refname,
1437 sha1, &sb_refname, &read_flags)) {
1438 *flags |= read_flags;
1439
1440 /* In reading mode, refs must eventually resolve */
1441 if (resolve_flags & RESOLVE_REF_READING)
1442 return NULL;
1443
1444 /*
1445 * Otherwise a missing ref is OK. But the files backend
1446 * may show errors besides ENOENT if there are
1447 * similarly-named refs.
1448 */
1449 if (errno != ENOENT &&
1450 errno != EISDIR &&
1451 errno != ENOTDIR)
1452 return NULL;
1453
1454 hashclr(sha1);
1455 if (*flags & REF_BAD_NAME)
1456 *flags |= REF_ISBROKEN;
1457 return refname;
1458 }
1459
1460 *flags |= read_flags;
1461
1462 if (!(read_flags & REF_ISSYMREF)) {
1463 if (*flags & REF_BAD_NAME) {
1464 hashclr(sha1);
1465 *flags |= REF_ISBROKEN;
1466 }
1467 return refname;
1468 }
1469
1470 refname = sb_refname.buf;
1471 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1472 hashclr(sha1);
1473 return refname;
1474 }
1475 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1476 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1477 !refname_is_safe(refname)) {
1478 errno = EINVAL;
1479 return NULL;
1480 }
1481
1482 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1483 }
1484 }
1485
1486 errno = ELOOP;
1487 return NULL;
1488 }
1489
1490 /* backend functions */
1491 int refs_init_db(struct strbuf *err)
1492 {
1493 struct ref_store *refs = get_main_ref_store();
1494
1495 return refs->be->init_db(refs, err);
1496 }
1497
1498 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1499 unsigned char *sha1, int *flags)
1500 {
1501 return refs_resolve_ref_unsafe(get_main_ref_store(), refname,
1502 resolve_flags, sha1, flags);
1503 }
1504
1505 int resolve_gitlink_ref(const char *submodule, const char *refname,
1506 unsigned char *sha1)
1507 {
1508 struct ref_store *refs;
1509 int flags;
1510
1511 refs = get_submodule_ref_store(submodule);
1512
1513 if (!refs)
1514 return -1;
1515
1516 if (!refs_resolve_ref_unsafe(refs, refname, 0, sha1, &flags) ||
1517 is_null_sha1(sha1))
1518 return -1;
1519 return 0;
1520 }
1521
1522 struct ref_store_hash_entry
1523 {
1524 struct hashmap_entry ent; /* must be the first member! */
1525
1526 struct ref_store *refs;
1527
1528 /* NUL-terminated identifier of the ref store: */
1529 char name[FLEX_ARRAY];
1530 };
1531
1532 static int ref_store_hash_cmp(const void *unused_cmp_data,
1533 const void *entry, const void *entry_or_key,
1534 const void *keydata)
1535 {
1536 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1537 const char *name = keydata ? keydata : e2->name;
1538
1539 return strcmp(e1->name, name);
1540 }
1541
1542 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1543 const char *name, struct ref_store *refs)
1544 {
1545 struct ref_store_hash_entry *entry;
1546
1547 FLEX_ALLOC_STR(entry, name, name);
1548 hashmap_entry_init(entry, strhash(name));
1549 entry->refs = refs;
1550 return entry;
1551 }
1552
1553 /* A pointer to the ref_store for the main repository: */
1554 static struct ref_store *main_ref_store;
1555
1556 /* A hashmap of ref_stores, stored by submodule name: */
1557 static struct hashmap submodule_ref_stores;
1558
1559 /* A hashmap of ref_stores, stored by worktree id: */
1560 static struct hashmap worktree_ref_stores;
1561
1562 /*
1563 * Look up a ref store by name. If that ref_store hasn't been
1564 * registered yet, return NULL.
1565 */
1566 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1567 const char *name)
1568 {
1569 struct ref_store_hash_entry *entry;
1570
1571 if (!map->tablesize)
1572 /* It's initialized on demand in register_ref_store(). */
1573 return NULL;
1574
1575 entry = hashmap_get_from_hash(map, strhash(name), name);
1576 return entry ? entry->refs : NULL;
1577 }
1578
1579 /*
1580 * Create, record, and return a ref_store instance for the specified
1581 * gitdir.
1582 */
1583 static struct ref_store *ref_store_init(const char *gitdir,
1584 unsigned int flags)
1585 {
1586 const char *be_name = "files";
1587 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1588 struct ref_store *refs;
1589
1590 if (!be)
1591 die("BUG: reference backend %s is unknown", be_name);
1592
1593 refs = be->init(gitdir, flags);
1594 return refs;
1595 }
1596
1597 struct ref_store *get_main_ref_store(void)
1598 {
1599 if (main_ref_store)
1600 return main_ref_store;
1601
1602 main_ref_store = ref_store_init(get_git_dir(), REF_STORE_ALL_CAPS);
1603 return main_ref_store;
1604 }
1605
1606 /*
1607 * Associate a ref store with a name. It is a fatal error to call this
1608 * function twice for the same name.
1609 */
1610 static void register_ref_store_map(struct hashmap *map,
1611 const char *type,
1612 struct ref_store *refs,
1613 const char *name)
1614 {
1615 if (!map->tablesize)
1616 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1617
1618 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1619 die("BUG: %s ref_store '%s' initialized twice", type, name);
1620 }
1621
1622 struct ref_store *get_submodule_ref_store(const char *submodule)
1623 {
1624 struct strbuf submodule_sb = STRBUF_INIT;
1625 struct ref_store *refs;
1626 char *to_free = NULL;
1627 size_t len;
1628
1629 if (!submodule)
1630 return NULL;
1631
1632 len = strlen(submodule);
1633 while (len && is_dir_sep(submodule[len - 1]))
1634 len--;
1635 if (!len)
1636 return NULL;
1637
1638 if (submodule[len])
1639 /* We need to strip off one or more trailing slashes */
1640 submodule = to_free = xmemdupz(submodule, len);
1641
1642 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1643 if (refs)
1644 goto done;
1645
1646 strbuf_addstr(&submodule_sb, submodule);
1647 if (!is_nonbare_repository_dir(&submodule_sb))
1648 goto done;
1649
1650 if (submodule_to_gitdir(&submodule_sb, submodule))
1651 goto done;
1652
1653 /* assume that add_submodule_odb() has been called */
1654 refs = ref_store_init(submodule_sb.buf,
1655 REF_STORE_READ | REF_STORE_ODB);
1656 register_ref_store_map(&submodule_ref_stores, "submodule",
1657 refs, submodule);
1658
1659 done:
1660 strbuf_release(&submodule_sb);
1661 free(to_free);
1662
1663 return refs;
1664 }
1665
1666 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1667 {
1668 struct ref_store *refs;
1669 const char *id;
1670
1671 if (wt->is_current)
1672 return get_main_ref_store();
1673
1674 id = wt->id ? wt->id : "/";
1675 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1676 if (refs)
1677 return refs;
1678
1679 if (wt->id)
1680 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1681 REF_STORE_ALL_CAPS);
1682 else
1683 refs = ref_store_init(get_git_common_dir(),
1684 REF_STORE_ALL_CAPS);
1685
1686 if (refs)
1687 register_ref_store_map(&worktree_ref_stores, "worktree",
1688 refs, id);
1689 return refs;
1690 }
1691
1692 void base_ref_store_init(struct ref_store *refs,
1693 const struct ref_storage_be *be)
1694 {
1695 refs->be = be;
1696 }
1697
1698 /* backend functions */
1699 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1700 {
1701 return refs->be->pack_refs(refs, flags);
1702 }
1703
1704 int refs_peel_ref(struct ref_store *refs, const char *refname,
1705 unsigned char *sha1)
1706 {
1707 int flag;
1708 unsigned char base[20];
1709
1710 if (current_ref_iter && current_ref_iter->refname == refname) {
1711 struct object_id peeled;
1712
1713 if (ref_iterator_peel(current_ref_iter, &peeled))
1714 return -1;
1715 hashcpy(sha1, peeled.hash);
1716 return 0;
1717 }
1718
1719 if (refs_read_ref_full(refs, refname,
1720 RESOLVE_REF_READING, base, &flag))
1721 return -1;
1722
1723 return peel_object(base, sha1);
1724 }
1725
1726 int peel_ref(const char *refname, unsigned char *sha1)
1727 {
1728 return refs_peel_ref(get_main_ref_store(), refname, sha1);
1729 }
1730
1731 int refs_create_symref(struct ref_store *refs,
1732 const char *ref_target,
1733 const char *refs_heads_master,
1734 const char *logmsg)
1735 {
1736 return refs->be->create_symref(refs, ref_target,
1737 refs_heads_master,
1738 logmsg);
1739 }
1740
1741 int create_symref(const char *ref_target, const char *refs_heads_master,
1742 const char *logmsg)
1743 {
1744 return refs_create_symref(get_main_ref_store(), ref_target,
1745 refs_heads_master, logmsg);
1746 }
1747
1748 int ref_update_reject_duplicates(struct string_list *refnames,
1749 struct strbuf *err)
1750 {
1751 size_t i, n = refnames->nr;
1752
1753 assert(err);
1754
1755 for (i = 1; i < n; i++) {
1756 int cmp = strcmp(refnames->items[i - 1].string,
1757 refnames->items[i].string);
1758
1759 if (!cmp) {
1760 strbuf_addf(err,
1761 "multiple updates for ref '%s' not allowed.",
1762 refnames->items[i].string);
1763 return 1;
1764 } else if (cmp > 0) {
1765 die("BUG: ref_update_reject_duplicates() received unsorted list");
1766 }
1767 }
1768 return 0;
1769 }
1770
1771 int ref_transaction_prepare(struct ref_transaction *transaction,
1772 struct strbuf *err)
1773 {
1774 struct ref_store *refs = transaction->ref_store;
1775
1776 switch (transaction->state) {
1777 case REF_TRANSACTION_OPEN:
1778 /* Good. */
1779 break;
1780 case REF_TRANSACTION_PREPARED:
1781 die("BUG: prepare called twice on reference transaction");
1782 break;
1783 case REF_TRANSACTION_CLOSED:
1784 die("BUG: prepare called on a closed reference transaction");
1785 break;
1786 default:
1787 die("BUG: unexpected reference transaction state");
1788 break;
1789 }
1790
1791 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1792 strbuf_addstr(err,
1793 _("ref updates forbidden inside quarantine environment"));
1794 return -1;
1795 }
1796
1797 return refs->be->transaction_prepare(refs, transaction, err);
1798 }
1799
1800 int ref_transaction_abort(struct ref_transaction *transaction,
1801 struct strbuf *err)
1802 {
1803 struct ref_store *refs = transaction->ref_store;
1804 int ret = 0;
1805
1806 switch (transaction->state) {
1807 case REF_TRANSACTION_OPEN:
1808 /* No need to abort explicitly. */
1809 break;
1810 case REF_TRANSACTION_PREPARED:
1811 ret = refs->be->transaction_abort(refs, transaction, err);
1812 break;
1813 case REF_TRANSACTION_CLOSED:
1814 die("BUG: abort called on a closed reference transaction");
1815 break;
1816 default:
1817 die("BUG: unexpected reference transaction state");
1818 break;
1819 }
1820
1821 ref_transaction_free(transaction);
1822 return ret;
1823 }
1824
1825 int ref_transaction_commit(struct ref_transaction *transaction,
1826 struct strbuf *err)
1827 {
1828 struct ref_store *refs = transaction->ref_store;
1829 int ret;
1830
1831 switch (transaction->state) {
1832 case REF_TRANSACTION_OPEN:
1833 /* Need to prepare first. */
1834 ret = ref_transaction_prepare(transaction, err);
1835 if (ret)
1836 return ret;
1837 break;
1838 case REF_TRANSACTION_PREPARED:
1839 /* Fall through to finish. */
1840 break;
1841 case REF_TRANSACTION_CLOSED:
1842 die("BUG: commit called on a closed reference transaction");
1843 break;
1844 default:
1845 die("BUG: unexpected reference transaction state");
1846 break;
1847 }
1848
1849 return refs->be->transaction_finish(refs, transaction, err);
1850 }
1851
1852 int refs_verify_refname_available(struct ref_store *refs,
1853 const char *refname,
1854 const struct string_list *extras,
1855 const struct string_list *skip,
1856 struct strbuf *err)
1857 {
1858 const char *slash;
1859 const char *extra_refname;
1860 struct strbuf dirname = STRBUF_INIT;
1861 struct strbuf referent = STRBUF_INIT;
1862 struct object_id oid;
1863 unsigned int type;
1864 struct ref_iterator *iter;
1865 int ok;
1866 int ret = -1;
1867
1868 /*
1869 * For the sake of comments in this function, suppose that
1870 * refname is "refs/foo/bar".
1871 */
1872
1873 assert(err);
1874
1875 strbuf_grow(&dirname, strlen(refname) + 1);
1876 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1877 /* Expand dirname to the new prefix, not including the trailing slash: */
1878 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1879
1880 /*
1881 * We are still at a leading dir of the refname (e.g.,
1882 * "refs/foo"; if there is a reference with that name,
1883 * it is a conflict, *unless* it is in skip.
1884 */
1885 if (skip && string_list_has_string(skip, dirname.buf))
1886 continue;
1887
1888 if (!refs_read_raw_ref(refs, dirname.buf, oid.hash, &referent, &type)) {
1889 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1890 dirname.buf, refname);
1891 goto cleanup;
1892 }
1893
1894 if (extras && string_list_has_string(extras, dirname.buf)) {
1895 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1896 refname, dirname.buf);
1897 goto cleanup;
1898 }
1899 }
1900
1901 /*
1902 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1903 * There is no point in searching for a reference with that
1904 * name, because a refname isn't considered to conflict with
1905 * itself. But we still need to check for references whose
1906 * names are in the "refs/foo/bar/" namespace, because they
1907 * *do* conflict.
1908 */
1909 strbuf_addstr(&dirname, refname + dirname.len);
1910 strbuf_addch(&dirname, '/');
1911
1912 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
1913 DO_FOR_EACH_INCLUDE_BROKEN);
1914 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
1915 if (skip &&
1916 string_list_has_string(skip, iter->refname))
1917 continue;
1918
1919 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1920 iter->refname, refname);
1921 ref_iterator_abort(iter);
1922 goto cleanup;
1923 }
1924
1925 if (ok != ITER_DONE)
1926 die("BUG: error while iterating over references");
1927
1928 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
1929 if (extra_refname)
1930 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1931 refname, extra_refname);
1932 else
1933 ret = 0;
1934
1935 cleanup:
1936 strbuf_release(&referent);
1937 strbuf_release(&dirname);
1938 return ret;
1939 }
1940
1941 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1942 {
1943 struct ref_iterator *iter;
1944
1945 iter = refs->be->reflog_iterator_begin(refs);
1946
1947 return do_for_each_ref_iterator(iter, fn, cb_data);
1948 }
1949
1950 int for_each_reflog(each_ref_fn fn, void *cb_data)
1951 {
1952 return refs_for_each_reflog(get_main_ref_store(), fn, cb_data);
1953 }
1954
1955 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
1956 const char *refname,
1957 each_reflog_ent_fn fn,
1958 void *cb_data)
1959 {
1960 return refs->be->for_each_reflog_ent_reverse(refs, refname,
1961 fn, cb_data);
1962 }
1963
1964 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
1965 void *cb_data)
1966 {
1967 return refs_for_each_reflog_ent_reverse(get_main_ref_store(),
1968 refname, fn, cb_data);
1969 }
1970
1971 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
1972 each_reflog_ent_fn fn, void *cb_data)
1973 {
1974 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
1975 }
1976
1977 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
1978 void *cb_data)
1979 {
1980 return refs_for_each_reflog_ent(get_main_ref_store(), refname,
1981 fn, cb_data);
1982 }
1983
1984 int refs_reflog_exists(struct ref_store *refs, const char *refname)
1985 {
1986 return refs->be->reflog_exists(refs, refname);
1987 }
1988
1989 int reflog_exists(const char *refname)
1990 {
1991 return refs_reflog_exists(get_main_ref_store(), refname);
1992 }
1993
1994 int refs_create_reflog(struct ref_store *refs, const char *refname,
1995 int force_create, struct strbuf *err)
1996 {
1997 return refs->be->create_reflog(refs, refname, force_create, err);
1998 }
1999
2000 int safe_create_reflog(const char *refname, int force_create,
2001 struct strbuf *err)
2002 {
2003 return refs_create_reflog(get_main_ref_store(), refname,
2004 force_create, err);
2005 }
2006
2007 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2008 {
2009 return refs->be->delete_reflog(refs, refname);
2010 }
2011
2012 int delete_reflog(const char *refname)
2013 {
2014 return refs_delete_reflog(get_main_ref_store(), refname);
2015 }
2016
2017 int refs_reflog_expire(struct ref_store *refs,
2018 const char *refname, const unsigned char *sha1,
2019 unsigned int flags,
2020 reflog_expiry_prepare_fn prepare_fn,
2021 reflog_expiry_should_prune_fn should_prune_fn,
2022 reflog_expiry_cleanup_fn cleanup_fn,
2023 void *policy_cb_data)
2024 {
2025 return refs->be->reflog_expire(refs, refname, sha1, flags,
2026 prepare_fn, should_prune_fn,
2027 cleanup_fn, policy_cb_data);
2028 }
2029
2030 int reflog_expire(const char *refname, const unsigned char *sha1,
2031 unsigned int flags,
2032 reflog_expiry_prepare_fn prepare_fn,
2033 reflog_expiry_should_prune_fn should_prune_fn,
2034 reflog_expiry_cleanup_fn cleanup_fn,
2035 void *policy_cb_data)
2036 {
2037 return refs_reflog_expire(get_main_ref_store(),
2038 refname, sha1, flags,
2039 prepare_fn, should_prune_fn,
2040 cleanup_fn, policy_cb_data);
2041 }
2042
2043 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2044 struct strbuf *err)
2045 {
2046 struct ref_store *refs = transaction->ref_store;
2047
2048 return refs->be->initial_transaction_commit(refs, transaction, err);
2049 }
2050
2051 int refs_delete_refs(struct ref_store *refs, const char *msg,
2052 struct string_list *refnames, unsigned int flags)
2053 {
2054 return refs->be->delete_refs(refs, msg, refnames, flags);
2055 }
2056
2057 int delete_refs(const char *msg, struct string_list *refnames,
2058 unsigned int flags)
2059 {
2060 return refs_delete_refs(get_main_ref_store(), msg, refnames, flags);
2061 }
2062
2063 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2064 const char *newref, const char *logmsg)
2065 {
2066 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2067 }
2068
2069 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2070 {
2071 return refs_rename_ref(get_main_ref_store(), oldref, newref, logmsg);
2072 }
2073
2074 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2075 const char *newref, const char *logmsg)
2076 {
2077 return refs->be->copy_ref(refs, oldref, newref, logmsg);
2078 }
2079
2080 int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2081 {
2082 return refs_copy_existing_ref(get_main_ref_store(), oldref, newref, logmsg);
2083 }