refs: convert update_ref and refs_update_ref to use 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 struct object_id *oid,
578 const struct object_id *old_oid, struct strbuf *err)
579 {
580 const char *filename;
581 int fd;
582 static struct lock_file lock;
583 struct strbuf buf = STRBUF_INIT;
584 int ret = -1;
585
586 strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
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_oid) {
599 struct object_id actual_old_oid;
600
601 if (read_ref(pseudoref, actual_old_oid.hash))
602 die("could not read ref '%s'", pseudoref);
603 if (oidcmp(&actual_old_oid, old_oid)) {
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 refs_update_ref(struct ref_store *refs, const char *msg,
989 const char *refname, const struct object_id *new_oid,
990 const struct object_id *old_oid, unsigned int flags,
991 enum action_on_err onerr)
992 {
993 struct ref_transaction *t = NULL;
994 struct strbuf err = STRBUF_INIT;
995 int ret = 0;
996
997 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
998 assert(refs == get_main_ref_store());
999 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1000 } else {
1001 t = ref_store_transaction_begin(refs, &err);
1002 if (!t ||
1003 ref_transaction_update(t, refname, new_oid ? new_oid->hash : NULL,
1004 old_oid ? old_oid->hash : NULL,
1005 flags, msg, &err) ||
1006 ref_transaction_commit(t, &err)) {
1007 ret = 1;
1008 ref_transaction_free(t);
1009 }
1010 }
1011 if (ret) {
1012 const char *str = "update_ref failed for ref '%s': %s";
1013
1014 switch (onerr) {
1015 case UPDATE_REFS_MSG_ON_ERR:
1016 error(str, refname, err.buf);
1017 break;
1018 case UPDATE_REFS_DIE_ON_ERR:
1019 die(str, refname, err.buf);
1020 break;
1021 case UPDATE_REFS_QUIET_ON_ERR:
1022 break;
1023 }
1024 strbuf_release(&err);
1025 return 1;
1026 }
1027 strbuf_release(&err);
1028 if (t)
1029 ref_transaction_free(t);
1030 return 0;
1031 }
1032
1033 int update_ref(const char *msg, const char *refname,
1034 const struct object_id *new_oid,
1035 const struct object_id *old_oid,
1036 unsigned int flags, enum action_on_err onerr)
1037 {
1038 return refs_update_ref(get_main_ref_store(), msg, refname, new_oid,
1039 old_oid, flags, onerr);
1040 }
1041
1042 char *shorten_unambiguous_ref(const char *refname, int strict)
1043 {
1044 int i;
1045 static char **scanf_fmts;
1046 static int nr_rules;
1047 char *short_name;
1048 struct strbuf resolved_buf = STRBUF_INIT;
1049
1050 if (!nr_rules) {
1051 /*
1052 * Pre-generate scanf formats from ref_rev_parse_rules[].
1053 * Generate a format suitable for scanf from a
1054 * ref_rev_parse_rules rule by interpolating "%s" at the
1055 * location of the "%.*s".
1056 */
1057 size_t total_len = 0;
1058 size_t offset = 0;
1059
1060 /* the rule list is NULL terminated, count them first */
1061 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1062 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1063 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1064
1065 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1066
1067 offset = 0;
1068 for (i = 0; i < nr_rules; i++) {
1069 assert(offset < total_len);
1070 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1071 offset += snprintf(scanf_fmts[i], total_len - offset,
1072 ref_rev_parse_rules[i], 2, "%s") + 1;
1073 }
1074 }
1075
1076 /* bail out if there are no rules */
1077 if (!nr_rules)
1078 return xstrdup(refname);
1079
1080 /* buffer for scanf result, at most refname must fit */
1081 short_name = xstrdup(refname);
1082
1083 /* skip first rule, it will always match */
1084 for (i = nr_rules - 1; i > 0 ; --i) {
1085 int j;
1086 int rules_to_fail = i;
1087 int short_name_len;
1088
1089 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1090 continue;
1091
1092 short_name_len = strlen(short_name);
1093
1094 /*
1095 * in strict mode, all (except the matched one) rules
1096 * must fail to resolve to a valid non-ambiguous ref
1097 */
1098 if (strict)
1099 rules_to_fail = nr_rules;
1100
1101 /*
1102 * check if the short name resolves to a valid ref,
1103 * but use only rules prior to the matched one
1104 */
1105 for (j = 0; j < rules_to_fail; j++) {
1106 const char *rule = ref_rev_parse_rules[j];
1107
1108 /* skip matched rule */
1109 if (i == j)
1110 continue;
1111
1112 /*
1113 * the short name is ambiguous, if it resolves
1114 * (with this previous rule) to a valid ref
1115 * read_ref() returns 0 on success
1116 */
1117 strbuf_reset(&resolved_buf);
1118 strbuf_addf(&resolved_buf, rule,
1119 short_name_len, short_name);
1120 if (ref_exists(resolved_buf.buf))
1121 break;
1122 }
1123
1124 /*
1125 * short name is non-ambiguous if all previous rules
1126 * haven't resolved to a valid ref
1127 */
1128 if (j == rules_to_fail) {
1129 strbuf_release(&resolved_buf);
1130 return short_name;
1131 }
1132 }
1133
1134 strbuf_release(&resolved_buf);
1135 free(short_name);
1136 return xstrdup(refname);
1137 }
1138
1139 static struct string_list *hide_refs;
1140
1141 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1142 {
1143 const char *key;
1144 if (!strcmp("transfer.hiderefs", var) ||
1145 (!parse_config_key(var, section, NULL, NULL, &key) &&
1146 !strcmp(key, "hiderefs"))) {
1147 char *ref;
1148 int len;
1149
1150 if (!value)
1151 return config_error_nonbool(var);
1152 ref = xstrdup(value);
1153 len = strlen(ref);
1154 while (len && ref[len - 1] == '/')
1155 ref[--len] = '\0';
1156 if (!hide_refs) {
1157 hide_refs = xcalloc(1, sizeof(*hide_refs));
1158 hide_refs->strdup_strings = 1;
1159 }
1160 string_list_append(hide_refs, ref);
1161 }
1162 return 0;
1163 }
1164
1165 int ref_is_hidden(const char *refname, const char *refname_full)
1166 {
1167 int i;
1168
1169 if (!hide_refs)
1170 return 0;
1171 for (i = hide_refs->nr - 1; i >= 0; i--) {
1172 const char *match = hide_refs->items[i].string;
1173 const char *subject;
1174 int neg = 0;
1175 const char *p;
1176
1177 if (*match == '!') {
1178 neg = 1;
1179 match++;
1180 }
1181
1182 if (*match == '^') {
1183 subject = refname_full;
1184 match++;
1185 } else {
1186 subject = refname;
1187 }
1188
1189 /* refname can be NULL when namespaces are used. */
1190 if (subject &&
1191 skip_prefix(subject, match, &p) &&
1192 (!*p || *p == '/'))
1193 return !neg;
1194 }
1195 return 0;
1196 }
1197
1198 const char *find_descendant_ref(const char *dirname,
1199 const struct string_list *extras,
1200 const struct string_list *skip)
1201 {
1202 int pos;
1203
1204 if (!extras)
1205 return NULL;
1206
1207 /*
1208 * Look at the place where dirname would be inserted into
1209 * extras. If there is an entry at that position that starts
1210 * with dirname (remember, dirname includes the trailing
1211 * slash) and is not in skip, then we have a conflict.
1212 */
1213 for (pos = string_list_find_insert_index(extras, dirname, 0);
1214 pos < extras->nr; pos++) {
1215 const char *extra_refname = extras->items[pos].string;
1216
1217 if (!starts_with(extra_refname, dirname))
1218 break;
1219
1220 if (!skip || !string_list_has_string(skip, extra_refname))
1221 return extra_refname;
1222 }
1223 return NULL;
1224 }
1225
1226 int refs_rename_ref_available(struct ref_store *refs,
1227 const char *old_refname,
1228 const char *new_refname)
1229 {
1230 struct string_list skip = STRING_LIST_INIT_NODUP;
1231 struct strbuf err = STRBUF_INIT;
1232 int ok;
1233
1234 string_list_insert(&skip, old_refname);
1235 ok = !refs_verify_refname_available(refs, new_refname,
1236 NULL, &skip, &err);
1237 if (!ok)
1238 error("%s", err.buf);
1239
1240 string_list_clear(&skip, 0);
1241 strbuf_release(&err);
1242 return ok;
1243 }
1244
1245 int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1246 {
1247 struct object_id oid;
1248 int flag;
1249
1250 if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1251 oid.hash, &flag))
1252 return fn("HEAD", &oid, flag, cb_data);
1253
1254 return 0;
1255 }
1256
1257 int head_ref(each_ref_fn fn, void *cb_data)
1258 {
1259 return refs_head_ref(get_main_ref_store(), fn, cb_data);
1260 }
1261
1262 struct ref_iterator *refs_ref_iterator_begin(
1263 struct ref_store *refs,
1264 const char *prefix, int trim, int flags)
1265 {
1266 struct ref_iterator *iter;
1267
1268 if (ref_paranoia < 0)
1269 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1270 if (ref_paranoia)
1271 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1272
1273 iter = refs->be->iterator_begin(refs, prefix, flags);
1274
1275 /*
1276 * `iterator_begin()` already takes care of prefix, but we
1277 * might need to do some trimming:
1278 */
1279 if (trim)
1280 iter = prefix_ref_iterator_begin(iter, "", trim);
1281
1282 /* Sanity check for subclasses: */
1283 if (!iter->ordered)
1284 BUG("reference iterator is not ordered");
1285
1286 return iter;
1287 }
1288
1289 /*
1290 * Call fn for each reference in the specified submodule for which the
1291 * refname begins with prefix. If trim is non-zero, then trim that
1292 * many characters off the beginning of each refname before passing
1293 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1294 * include broken references in the iteration. If fn ever returns a
1295 * non-zero value, stop the iteration and return that value;
1296 * otherwise, return 0.
1297 */
1298 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1299 each_ref_fn fn, int trim, int flags, void *cb_data)
1300 {
1301 struct ref_iterator *iter;
1302
1303 if (!refs)
1304 return 0;
1305
1306 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1307
1308 return do_for_each_ref_iterator(iter, fn, cb_data);
1309 }
1310
1311 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1312 {
1313 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1314 }
1315
1316 int for_each_ref(each_ref_fn fn, void *cb_data)
1317 {
1318 return refs_for_each_ref(get_main_ref_store(), fn, cb_data);
1319 }
1320
1321 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1322 each_ref_fn fn, void *cb_data)
1323 {
1324 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1325 }
1326
1327 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1328 {
1329 return refs_for_each_ref_in(get_main_ref_store(), prefix, fn, cb_data);
1330 }
1331
1332 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1333 {
1334 unsigned int flag = 0;
1335
1336 if (broken)
1337 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1338 return do_for_each_ref(get_main_ref_store(),
1339 prefix, fn, 0, flag, cb_data);
1340 }
1341
1342 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1343 each_ref_fn fn, void *cb_data,
1344 unsigned int broken)
1345 {
1346 unsigned int flag = 0;
1347
1348 if (broken)
1349 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1350 return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1351 }
1352
1353 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1354 {
1355 return do_for_each_ref(get_main_ref_store(),
1356 git_replace_ref_base, fn,
1357 strlen(git_replace_ref_base),
1358 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1359 }
1360
1361 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1362 {
1363 struct strbuf buf = STRBUF_INIT;
1364 int ret;
1365 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1366 ret = do_for_each_ref(get_main_ref_store(),
1367 buf.buf, fn, 0, 0, cb_data);
1368 strbuf_release(&buf);
1369 return ret;
1370 }
1371
1372 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1373 {
1374 return do_for_each_ref(refs, "", fn, 0,
1375 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1376 }
1377
1378 int for_each_rawref(each_ref_fn fn, void *cb_data)
1379 {
1380 return refs_for_each_rawref(get_main_ref_store(), fn, cb_data);
1381 }
1382
1383 int refs_read_raw_ref(struct ref_store *ref_store,
1384 const char *refname, unsigned char *sha1,
1385 struct strbuf *referent, unsigned int *type)
1386 {
1387 return ref_store->be->read_raw_ref(ref_store, refname, sha1, referent, type);
1388 }
1389
1390 /* This function needs to return a meaningful errno on failure */
1391 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1392 const char *refname,
1393 int resolve_flags,
1394 unsigned char *sha1, int *flags)
1395 {
1396 static struct strbuf sb_refname = STRBUF_INIT;
1397 struct object_id unused_oid;
1398 int unused_flags;
1399 int symref_count;
1400
1401 if (!sha1)
1402 sha1 = unused_oid.hash;
1403 if (!flags)
1404 flags = &unused_flags;
1405
1406 *flags = 0;
1407
1408 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1409 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1410 !refname_is_safe(refname)) {
1411 errno = EINVAL;
1412 return NULL;
1413 }
1414
1415 /*
1416 * dwim_ref() uses REF_ISBROKEN to distinguish between
1417 * missing refs and refs that were present but invalid,
1418 * to complain about the latter to stderr.
1419 *
1420 * We don't know whether the ref exists, so don't set
1421 * REF_ISBROKEN yet.
1422 */
1423 *flags |= REF_BAD_NAME;
1424 }
1425
1426 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1427 unsigned int read_flags = 0;
1428
1429 if (refs_read_raw_ref(refs, refname,
1430 sha1, &sb_refname, &read_flags)) {
1431 *flags |= read_flags;
1432
1433 /* In reading mode, refs must eventually resolve */
1434 if (resolve_flags & RESOLVE_REF_READING)
1435 return NULL;
1436
1437 /*
1438 * Otherwise a missing ref is OK. But the files backend
1439 * may show errors besides ENOENT if there are
1440 * similarly-named refs.
1441 */
1442 if (errno != ENOENT &&
1443 errno != EISDIR &&
1444 errno != ENOTDIR)
1445 return NULL;
1446
1447 hashclr(sha1);
1448 if (*flags & REF_BAD_NAME)
1449 *flags |= REF_ISBROKEN;
1450 return refname;
1451 }
1452
1453 *flags |= read_flags;
1454
1455 if (!(read_flags & REF_ISSYMREF)) {
1456 if (*flags & REF_BAD_NAME) {
1457 hashclr(sha1);
1458 *flags |= REF_ISBROKEN;
1459 }
1460 return refname;
1461 }
1462
1463 refname = sb_refname.buf;
1464 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1465 hashclr(sha1);
1466 return refname;
1467 }
1468 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1469 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1470 !refname_is_safe(refname)) {
1471 errno = EINVAL;
1472 return NULL;
1473 }
1474
1475 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1476 }
1477 }
1478
1479 errno = ELOOP;
1480 return NULL;
1481 }
1482
1483 /* backend functions */
1484 int refs_init_db(struct strbuf *err)
1485 {
1486 struct ref_store *refs = get_main_ref_store();
1487
1488 return refs->be->init_db(refs, err);
1489 }
1490
1491 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1492 unsigned char *sha1, int *flags)
1493 {
1494 return refs_resolve_ref_unsafe(get_main_ref_store(), refname,
1495 resolve_flags, sha1, flags);
1496 }
1497
1498 int resolve_gitlink_ref(const char *submodule, const char *refname,
1499 unsigned char *sha1)
1500 {
1501 struct ref_store *refs;
1502 int flags;
1503
1504 refs = get_submodule_ref_store(submodule);
1505
1506 if (!refs)
1507 return -1;
1508
1509 if (!refs_resolve_ref_unsafe(refs, refname, 0, sha1, &flags) ||
1510 is_null_sha1(sha1))
1511 return -1;
1512 return 0;
1513 }
1514
1515 struct ref_store_hash_entry
1516 {
1517 struct hashmap_entry ent; /* must be the first member! */
1518
1519 struct ref_store *refs;
1520
1521 /* NUL-terminated identifier of the ref store: */
1522 char name[FLEX_ARRAY];
1523 };
1524
1525 static int ref_store_hash_cmp(const void *unused_cmp_data,
1526 const void *entry, const void *entry_or_key,
1527 const void *keydata)
1528 {
1529 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1530 const char *name = keydata ? keydata : e2->name;
1531
1532 return strcmp(e1->name, name);
1533 }
1534
1535 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1536 const char *name, struct ref_store *refs)
1537 {
1538 struct ref_store_hash_entry *entry;
1539
1540 FLEX_ALLOC_STR(entry, name, name);
1541 hashmap_entry_init(entry, strhash(name));
1542 entry->refs = refs;
1543 return entry;
1544 }
1545
1546 /* A pointer to the ref_store for the main repository: */
1547 static struct ref_store *main_ref_store;
1548
1549 /* A hashmap of ref_stores, stored by submodule name: */
1550 static struct hashmap submodule_ref_stores;
1551
1552 /* A hashmap of ref_stores, stored by worktree id: */
1553 static struct hashmap worktree_ref_stores;
1554
1555 /*
1556 * Look up a ref store by name. If that ref_store hasn't been
1557 * registered yet, return NULL.
1558 */
1559 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1560 const char *name)
1561 {
1562 struct ref_store_hash_entry *entry;
1563
1564 if (!map->tablesize)
1565 /* It's initialized on demand in register_ref_store(). */
1566 return NULL;
1567
1568 entry = hashmap_get_from_hash(map, strhash(name), name);
1569 return entry ? entry->refs : NULL;
1570 }
1571
1572 /*
1573 * Create, record, and return a ref_store instance for the specified
1574 * gitdir.
1575 */
1576 static struct ref_store *ref_store_init(const char *gitdir,
1577 unsigned int flags)
1578 {
1579 const char *be_name = "files";
1580 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1581 struct ref_store *refs;
1582
1583 if (!be)
1584 die("BUG: reference backend %s is unknown", be_name);
1585
1586 refs = be->init(gitdir, flags);
1587 return refs;
1588 }
1589
1590 struct ref_store *get_main_ref_store(void)
1591 {
1592 if (main_ref_store)
1593 return main_ref_store;
1594
1595 main_ref_store = ref_store_init(get_git_dir(), REF_STORE_ALL_CAPS);
1596 return main_ref_store;
1597 }
1598
1599 /*
1600 * Associate a ref store with a name. It is a fatal error to call this
1601 * function twice for the same name.
1602 */
1603 static void register_ref_store_map(struct hashmap *map,
1604 const char *type,
1605 struct ref_store *refs,
1606 const char *name)
1607 {
1608 if (!map->tablesize)
1609 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1610
1611 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1612 die("BUG: %s ref_store '%s' initialized twice", type, name);
1613 }
1614
1615 struct ref_store *get_submodule_ref_store(const char *submodule)
1616 {
1617 struct strbuf submodule_sb = STRBUF_INIT;
1618 struct ref_store *refs;
1619 char *to_free = NULL;
1620 size_t len;
1621
1622 if (!submodule)
1623 return NULL;
1624
1625 len = strlen(submodule);
1626 while (len && is_dir_sep(submodule[len - 1]))
1627 len--;
1628 if (!len)
1629 return NULL;
1630
1631 if (submodule[len])
1632 /* We need to strip off one or more trailing slashes */
1633 submodule = to_free = xmemdupz(submodule, len);
1634
1635 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1636 if (refs)
1637 goto done;
1638
1639 strbuf_addstr(&submodule_sb, submodule);
1640 if (!is_nonbare_repository_dir(&submodule_sb))
1641 goto done;
1642
1643 if (submodule_to_gitdir(&submodule_sb, submodule))
1644 goto done;
1645
1646 /* assume that add_submodule_odb() has been called */
1647 refs = ref_store_init(submodule_sb.buf,
1648 REF_STORE_READ | REF_STORE_ODB);
1649 register_ref_store_map(&submodule_ref_stores, "submodule",
1650 refs, submodule);
1651
1652 done:
1653 strbuf_release(&submodule_sb);
1654 free(to_free);
1655
1656 return refs;
1657 }
1658
1659 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1660 {
1661 struct ref_store *refs;
1662 const char *id;
1663
1664 if (wt->is_current)
1665 return get_main_ref_store();
1666
1667 id = wt->id ? wt->id : "/";
1668 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1669 if (refs)
1670 return refs;
1671
1672 if (wt->id)
1673 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1674 REF_STORE_ALL_CAPS);
1675 else
1676 refs = ref_store_init(get_git_common_dir(),
1677 REF_STORE_ALL_CAPS);
1678
1679 if (refs)
1680 register_ref_store_map(&worktree_ref_stores, "worktree",
1681 refs, id);
1682 return refs;
1683 }
1684
1685 void base_ref_store_init(struct ref_store *refs,
1686 const struct ref_storage_be *be)
1687 {
1688 refs->be = be;
1689 }
1690
1691 /* backend functions */
1692 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1693 {
1694 return refs->be->pack_refs(refs, flags);
1695 }
1696
1697 int refs_peel_ref(struct ref_store *refs, const char *refname,
1698 unsigned char *sha1)
1699 {
1700 int flag;
1701 unsigned char base[20];
1702
1703 if (current_ref_iter && current_ref_iter->refname == refname) {
1704 struct object_id peeled;
1705
1706 if (ref_iterator_peel(current_ref_iter, &peeled))
1707 return -1;
1708 hashcpy(sha1, peeled.hash);
1709 return 0;
1710 }
1711
1712 if (refs_read_ref_full(refs, refname,
1713 RESOLVE_REF_READING, base, &flag))
1714 return -1;
1715
1716 return peel_object(base, sha1);
1717 }
1718
1719 int peel_ref(const char *refname, unsigned char *sha1)
1720 {
1721 return refs_peel_ref(get_main_ref_store(), refname, sha1);
1722 }
1723
1724 int refs_create_symref(struct ref_store *refs,
1725 const char *ref_target,
1726 const char *refs_heads_master,
1727 const char *logmsg)
1728 {
1729 return refs->be->create_symref(refs, ref_target,
1730 refs_heads_master,
1731 logmsg);
1732 }
1733
1734 int create_symref(const char *ref_target, const char *refs_heads_master,
1735 const char *logmsg)
1736 {
1737 return refs_create_symref(get_main_ref_store(), ref_target,
1738 refs_heads_master, logmsg);
1739 }
1740
1741 int ref_update_reject_duplicates(struct string_list *refnames,
1742 struct strbuf *err)
1743 {
1744 size_t i, n = refnames->nr;
1745
1746 assert(err);
1747
1748 for (i = 1; i < n; i++) {
1749 int cmp = strcmp(refnames->items[i - 1].string,
1750 refnames->items[i].string);
1751
1752 if (!cmp) {
1753 strbuf_addf(err,
1754 "multiple updates for ref '%s' not allowed.",
1755 refnames->items[i].string);
1756 return 1;
1757 } else if (cmp > 0) {
1758 die("BUG: ref_update_reject_duplicates() received unsorted list");
1759 }
1760 }
1761 return 0;
1762 }
1763
1764 int ref_transaction_prepare(struct ref_transaction *transaction,
1765 struct strbuf *err)
1766 {
1767 struct ref_store *refs = transaction->ref_store;
1768
1769 switch (transaction->state) {
1770 case REF_TRANSACTION_OPEN:
1771 /* Good. */
1772 break;
1773 case REF_TRANSACTION_PREPARED:
1774 die("BUG: prepare called twice on reference transaction");
1775 break;
1776 case REF_TRANSACTION_CLOSED:
1777 die("BUG: prepare called on a closed reference transaction");
1778 break;
1779 default:
1780 die("BUG: unexpected reference transaction state");
1781 break;
1782 }
1783
1784 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1785 strbuf_addstr(err,
1786 _("ref updates forbidden inside quarantine environment"));
1787 return -1;
1788 }
1789
1790 return refs->be->transaction_prepare(refs, transaction, err);
1791 }
1792
1793 int ref_transaction_abort(struct ref_transaction *transaction,
1794 struct strbuf *err)
1795 {
1796 struct ref_store *refs = transaction->ref_store;
1797 int ret = 0;
1798
1799 switch (transaction->state) {
1800 case REF_TRANSACTION_OPEN:
1801 /* No need to abort explicitly. */
1802 break;
1803 case REF_TRANSACTION_PREPARED:
1804 ret = refs->be->transaction_abort(refs, transaction, err);
1805 break;
1806 case REF_TRANSACTION_CLOSED:
1807 die("BUG: abort called on a closed reference transaction");
1808 break;
1809 default:
1810 die("BUG: unexpected reference transaction state");
1811 break;
1812 }
1813
1814 ref_transaction_free(transaction);
1815 return ret;
1816 }
1817
1818 int ref_transaction_commit(struct ref_transaction *transaction,
1819 struct strbuf *err)
1820 {
1821 struct ref_store *refs = transaction->ref_store;
1822 int ret;
1823
1824 switch (transaction->state) {
1825 case REF_TRANSACTION_OPEN:
1826 /* Need to prepare first. */
1827 ret = ref_transaction_prepare(transaction, err);
1828 if (ret)
1829 return ret;
1830 break;
1831 case REF_TRANSACTION_PREPARED:
1832 /* Fall through to finish. */
1833 break;
1834 case REF_TRANSACTION_CLOSED:
1835 die("BUG: commit called on a closed reference transaction");
1836 break;
1837 default:
1838 die("BUG: unexpected reference transaction state");
1839 break;
1840 }
1841
1842 return refs->be->transaction_finish(refs, transaction, err);
1843 }
1844
1845 int refs_verify_refname_available(struct ref_store *refs,
1846 const char *refname,
1847 const struct string_list *extras,
1848 const struct string_list *skip,
1849 struct strbuf *err)
1850 {
1851 const char *slash;
1852 const char *extra_refname;
1853 struct strbuf dirname = STRBUF_INIT;
1854 struct strbuf referent = STRBUF_INIT;
1855 struct object_id oid;
1856 unsigned int type;
1857 struct ref_iterator *iter;
1858 int ok;
1859 int ret = -1;
1860
1861 /*
1862 * For the sake of comments in this function, suppose that
1863 * refname is "refs/foo/bar".
1864 */
1865
1866 assert(err);
1867
1868 strbuf_grow(&dirname, strlen(refname) + 1);
1869 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1870 /* Expand dirname to the new prefix, not including the trailing slash: */
1871 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1872
1873 /*
1874 * We are still at a leading dir of the refname (e.g.,
1875 * "refs/foo"; if there is a reference with that name,
1876 * it is a conflict, *unless* it is in skip.
1877 */
1878 if (skip && string_list_has_string(skip, dirname.buf))
1879 continue;
1880
1881 if (!refs_read_raw_ref(refs, dirname.buf, oid.hash, &referent, &type)) {
1882 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1883 dirname.buf, refname);
1884 goto cleanup;
1885 }
1886
1887 if (extras && string_list_has_string(extras, dirname.buf)) {
1888 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1889 refname, dirname.buf);
1890 goto cleanup;
1891 }
1892 }
1893
1894 /*
1895 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1896 * There is no point in searching for a reference with that
1897 * name, because a refname isn't considered to conflict with
1898 * itself. But we still need to check for references whose
1899 * names are in the "refs/foo/bar/" namespace, because they
1900 * *do* conflict.
1901 */
1902 strbuf_addstr(&dirname, refname + dirname.len);
1903 strbuf_addch(&dirname, '/');
1904
1905 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
1906 DO_FOR_EACH_INCLUDE_BROKEN);
1907 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
1908 if (skip &&
1909 string_list_has_string(skip, iter->refname))
1910 continue;
1911
1912 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1913 iter->refname, refname);
1914 ref_iterator_abort(iter);
1915 goto cleanup;
1916 }
1917
1918 if (ok != ITER_DONE)
1919 die("BUG: error while iterating over references");
1920
1921 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
1922 if (extra_refname)
1923 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1924 refname, extra_refname);
1925 else
1926 ret = 0;
1927
1928 cleanup:
1929 strbuf_release(&referent);
1930 strbuf_release(&dirname);
1931 return ret;
1932 }
1933
1934 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1935 {
1936 struct ref_iterator *iter;
1937
1938 iter = refs->be->reflog_iterator_begin(refs);
1939
1940 return do_for_each_ref_iterator(iter, fn, cb_data);
1941 }
1942
1943 int for_each_reflog(each_ref_fn fn, void *cb_data)
1944 {
1945 return refs_for_each_reflog(get_main_ref_store(), fn, cb_data);
1946 }
1947
1948 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
1949 const char *refname,
1950 each_reflog_ent_fn fn,
1951 void *cb_data)
1952 {
1953 return refs->be->for_each_reflog_ent_reverse(refs, refname,
1954 fn, cb_data);
1955 }
1956
1957 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
1958 void *cb_data)
1959 {
1960 return refs_for_each_reflog_ent_reverse(get_main_ref_store(),
1961 refname, fn, cb_data);
1962 }
1963
1964 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
1965 each_reflog_ent_fn fn, void *cb_data)
1966 {
1967 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
1968 }
1969
1970 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
1971 void *cb_data)
1972 {
1973 return refs_for_each_reflog_ent(get_main_ref_store(), refname,
1974 fn, cb_data);
1975 }
1976
1977 int refs_reflog_exists(struct ref_store *refs, const char *refname)
1978 {
1979 return refs->be->reflog_exists(refs, refname);
1980 }
1981
1982 int reflog_exists(const char *refname)
1983 {
1984 return refs_reflog_exists(get_main_ref_store(), refname);
1985 }
1986
1987 int refs_create_reflog(struct ref_store *refs, const char *refname,
1988 int force_create, struct strbuf *err)
1989 {
1990 return refs->be->create_reflog(refs, refname, force_create, err);
1991 }
1992
1993 int safe_create_reflog(const char *refname, int force_create,
1994 struct strbuf *err)
1995 {
1996 return refs_create_reflog(get_main_ref_store(), refname,
1997 force_create, err);
1998 }
1999
2000 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2001 {
2002 return refs->be->delete_reflog(refs, refname);
2003 }
2004
2005 int delete_reflog(const char *refname)
2006 {
2007 return refs_delete_reflog(get_main_ref_store(), refname);
2008 }
2009
2010 int refs_reflog_expire(struct ref_store *refs,
2011 const char *refname, const unsigned char *sha1,
2012 unsigned int flags,
2013 reflog_expiry_prepare_fn prepare_fn,
2014 reflog_expiry_should_prune_fn should_prune_fn,
2015 reflog_expiry_cleanup_fn cleanup_fn,
2016 void *policy_cb_data)
2017 {
2018 return refs->be->reflog_expire(refs, refname, sha1, flags,
2019 prepare_fn, should_prune_fn,
2020 cleanup_fn, policy_cb_data);
2021 }
2022
2023 int reflog_expire(const char *refname, const unsigned char *sha1,
2024 unsigned int flags,
2025 reflog_expiry_prepare_fn prepare_fn,
2026 reflog_expiry_should_prune_fn should_prune_fn,
2027 reflog_expiry_cleanup_fn cleanup_fn,
2028 void *policy_cb_data)
2029 {
2030 return refs_reflog_expire(get_main_ref_store(),
2031 refname, sha1, flags,
2032 prepare_fn, should_prune_fn,
2033 cleanup_fn, policy_cb_data);
2034 }
2035
2036 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2037 struct strbuf *err)
2038 {
2039 struct ref_store *refs = transaction->ref_store;
2040
2041 return refs->be->initial_transaction_commit(refs, transaction, err);
2042 }
2043
2044 int refs_delete_refs(struct ref_store *refs, const char *msg,
2045 struct string_list *refnames, unsigned int flags)
2046 {
2047 return refs->be->delete_refs(refs, msg, refnames, flags);
2048 }
2049
2050 int delete_refs(const char *msg, struct string_list *refnames,
2051 unsigned int flags)
2052 {
2053 return refs_delete_refs(get_main_ref_store(), msg, refnames, flags);
2054 }
2055
2056 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2057 const char *newref, const char *logmsg)
2058 {
2059 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2060 }
2061
2062 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2063 {
2064 return refs_rename_ref(get_main_ref_store(), oldref, newref, logmsg);
2065 }
2066
2067 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2068 const char *newref, const char *logmsg)
2069 {
2070 return refs->be->copy_ref(refs, oldref, newref, logmsg);
2071 }
2072
2073 int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2074 {
2075 return refs_copy_existing_ref(get_main_ref_store(), oldref, newref, logmsg);
2076 }