1/*
2 * The backend-independent part of the reference module.
3 */
4
5#include "cache.h"
6#include "lockfile.h"
7#include "refs.h"
8#include "refs/refs-internal.h"
9#include "object.h"
10#include "tag.h"
11
12/*
13 * How to handle various characters in refnames:
14 * 0: An acceptable character for refs
15 * 1: End-of-component
16 * 2: ., look for a preceding . to reject .. in refs
17 * 3: {, look for a preceding @ to reject @{ in refs
18 * 4: A bad character: ASCII control characters, and
19 * ":", "?", "[", "\", "^", "~", SP, or TAB
20 * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
21 */
22static unsigned char refname_disposition[256] = {
23 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
24 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
25 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
26 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
27 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
28 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
29 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
30 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
31};
32
33/*
34 * Try to read one refname component from the front of refname.
35 * Return the length of the component found, or -1 if the component is
36 * not legal. It is legal if it is something reasonable to have under
37 * ".git/refs/"; We do not like it if:
38 *
39 * - any path component of it begins with ".", or
40 * - it has double dots "..", or
41 * - it has ASCII control characters, or
42 * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
43 * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
44 * - it ends with a "/", or
45 * - it ends with ".lock", or
46 * - it contains a "@{" portion
47 */
48static int check_refname_component(const char *refname, int *flags)
49{
50 const char *cp;
51 char last = '\0';
52
53 for (cp = refname; ; cp++) {
54 int ch = *cp & 255;
55 unsigned char disp = refname_disposition[ch];
56 switch (disp) {
57 case 1:
58 goto out;
59 case 2:
60 if (last == '.')
61 return -1; /* Refname contains "..". */
62 break;
63 case 3:
64 if (last == '@')
65 return -1; /* Refname contains "@{". */
66 break;
67 case 4:
68 return -1;
69 case 5:
70 if (!(*flags & REFNAME_REFSPEC_PATTERN))
71 return -1; /* refspec can't be a pattern */
72
73 /*
74 * Unset the pattern flag so that we only accept
75 * a single asterisk for one side of refspec.
76 */
77 *flags &= ~ REFNAME_REFSPEC_PATTERN;
78 break;
79 }
80 last = ch;
81 }
82out:
83 if (cp == refname)
84 return 0; /* Component has zero length. */
85 if (refname[0] == '.')
86 return -1; /* Component starts with '.'. */
87 if (cp - refname >= LOCK_SUFFIX_LEN &&
88 !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
89 return -1; /* Refname ends with ".lock". */
90 return cp - refname;
91}
92
93int check_refname_format(const char *refname, int flags)
94{
95 int component_len, component_count = 0;
96
97 if (!strcmp(refname, "@"))
98 /* Refname is a single character '@'. */
99 return -1;
100
101 while (1) {
102 /* We are at the start of a path component. */
103 component_len = check_refname_component(refname, &flags);
104 if (component_len <= 0)
105 return -1;
106
107 component_count++;
108 if (refname[component_len] == '\0')
109 break;
110 /* Skip to next component. */
111 refname += component_len + 1;
112 }
113
114 if (refname[component_len - 1] == '.')
115 return -1; /* Refname ends with '.'. */
116 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
117 return -1; /* Refname has only one component. */
118 return 0;
119}
120
121int refname_is_safe(const char *refname)
122{
123 if (starts_with(refname, "refs/")) {
124 char *buf;
125 int result;
126
127 buf = xmalloc(strlen(refname) + 1);
128 /*
129 * Does the refname try to escape refs/?
130 * For example: refs/foo/../bar is safe but refs/foo/../../bar
131 * is not.
132 */
133 result = !normalize_path_copy(buf, refname + strlen("refs/"));
134 free(buf);
135 return result;
136 }
137 while (*refname) {
138 if (!isupper(*refname) && *refname != '_')
139 return 0;
140 refname++;
141 }
142 return 1;
143}
144
145char *resolve_refdup(const char *refname, int resolve_flags,
146 unsigned char *sha1, int *flags)
147{
148 return xstrdup_or_null(resolve_ref_unsafe(refname, resolve_flags,
149 sha1, flags));
150}
151
152/* The argument to filter_refs */
153struct ref_filter {
154 const char *pattern;
155 each_ref_fn *fn;
156 void *cb_data;
157};
158
159int read_ref_full(const char *refname, int resolve_flags, unsigned char *sha1, int *flags)
160{
161 if (resolve_ref_unsafe(refname, resolve_flags, sha1, flags))
162 return 0;
163 return -1;
164}
165
166int read_ref(const char *refname, unsigned char *sha1)
167{
168 return read_ref_full(refname, RESOLVE_REF_READING, sha1, NULL);
169}
170
171int ref_exists(const char *refname)
172{
173 unsigned char sha1[20];
174 return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, sha1, NULL);
175}
176
177static int filter_refs(const char *refname, const struct object_id *oid,
178 int flags, void *data)
179{
180 struct ref_filter *filter = (struct ref_filter *)data;
181
182 if (wildmatch(filter->pattern, refname, 0, NULL))
183 return 0;
184 return filter->fn(refname, oid, flags, filter->cb_data);
185}
186
187enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
188{
189 struct object *o = lookup_unknown_object(name);
190
191 if (o->type == OBJ_NONE) {
192 int type = sha1_object_info(name, NULL);
193 if (type < 0 || !object_as_type(o, type, 0))
194 return PEEL_INVALID;
195 }
196
197 if (o->type != OBJ_TAG)
198 return PEEL_NON_TAG;
199
200 o = deref_tag_noverify(o);
201 if (!o)
202 return PEEL_INVALID;
203
204 hashcpy(sha1, o->oid.hash);
205 return PEEL_PEELED;
206}
207
208struct warn_if_dangling_data {
209 FILE *fp;
210 const char *refname;
211 const struct string_list *refnames;
212 const char *msg_fmt;
213};
214
215static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
216 int flags, void *cb_data)
217{
218 struct warn_if_dangling_data *d = cb_data;
219 const char *resolves_to;
220 struct object_id junk;
221
222 if (!(flags & REF_ISSYMREF))
223 return 0;
224
225 resolves_to = resolve_ref_unsafe(refname, 0, junk.hash, NULL);
226 if (!resolves_to
227 || (d->refname
228 ? strcmp(resolves_to, d->refname)
229 : !string_list_has_string(d->refnames, resolves_to))) {
230 return 0;
231 }
232
233 fprintf(d->fp, d->msg_fmt, refname);
234 fputc('\n', d->fp);
235 return 0;
236}
237
238void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
239{
240 struct warn_if_dangling_data data;
241
242 data.fp = fp;
243 data.refname = refname;
244 data.refnames = NULL;
245 data.msg_fmt = msg_fmt;
246 for_each_rawref(warn_if_dangling_symref, &data);
247}
248
249void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
250{
251 struct warn_if_dangling_data data;
252
253 data.fp = fp;
254 data.refname = NULL;
255 data.refnames = refnames;
256 data.msg_fmt = msg_fmt;
257 for_each_rawref(warn_if_dangling_symref, &data);
258}
259
260int for_each_tag_ref(each_ref_fn fn, void *cb_data)
261{
262 return for_each_ref_in("refs/tags/", fn, cb_data);
263}
264
265int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
266{
267 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
268}
269
270int for_each_branch_ref(each_ref_fn fn, void *cb_data)
271{
272 return for_each_ref_in("refs/heads/", fn, cb_data);
273}
274
275int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
276{
277 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
278}
279
280int for_each_remote_ref(each_ref_fn fn, void *cb_data)
281{
282 return for_each_ref_in("refs/remotes/", fn, cb_data);
283}
284
285int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
286{
287 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
288}
289
290int head_ref_namespaced(each_ref_fn fn, void *cb_data)
291{
292 struct strbuf buf = STRBUF_INIT;
293 int ret = 0;
294 struct object_id oid;
295 int flag;
296
297 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
298 if (!read_ref_full(buf.buf, RESOLVE_REF_READING, oid.hash, &flag))
299 ret = fn(buf.buf, &oid, flag, cb_data);
300 strbuf_release(&buf);
301
302 return ret;
303}
304
305int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
306 const char *prefix, void *cb_data)
307{
308 struct strbuf real_pattern = STRBUF_INIT;
309 struct ref_filter filter;
310 int ret;
311
312 if (!prefix && !starts_with(pattern, "refs/"))
313 strbuf_addstr(&real_pattern, "refs/");
314 else if (prefix)
315 strbuf_addstr(&real_pattern, prefix);
316 strbuf_addstr(&real_pattern, pattern);
317
318 if (!has_glob_specials(pattern)) {
319 /* Append implied '/' '*' if not present. */
320 strbuf_complete(&real_pattern, '/');
321 /* No need to check for '*', there is none. */
322 strbuf_addch(&real_pattern, '*');
323 }
324
325 filter.pattern = real_pattern.buf;
326 filter.fn = fn;
327 filter.cb_data = cb_data;
328 ret = for_each_ref(filter_refs, &filter);
329
330 strbuf_release(&real_pattern);
331 return ret;
332}
333
334int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
335{
336 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
337}
338
339const char *prettify_refname(const char *name)
340{
341 return name + (
342 starts_with(name, "refs/heads/") ? 11 :
343 starts_with(name, "refs/tags/") ? 10 :
344 starts_with(name, "refs/remotes/") ? 13 :
345 0);
346}
347
348static const char *ref_rev_parse_rules[] = {
349 "%.*s",
350 "refs/%.*s",
351 "refs/tags/%.*s",
352 "refs/heads/%.*s",
353 "refs/remotes/%.*s",
354 "refs/remotes/%.*s/HEAD",
355 NULL
356};
357
358int refname_match(const char *abbrev_name, const char *full_name)
359{
360 const char **p;
361 const int abbrev_name_len = strlen(abbrev_name);
362
363 for (p = ref_rev_parse_rules; *p; p++) {
364 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
365 return 1;
366 }
367 }
368
369 return 0;
370}
371
372/*
373 * *string and *len will only be substituted, and *string returned (for
374 * later free()ing) if the string passed in is a magic short-hand form
375 * to name a branch.
376 */
377static char *substitute_branch_name(const char **string, int *len)
378{
379 struct strbuf buf = STRBUF_INIT;
380 int ret = interpret_branch_name(*string, *len, &buf);
381
382 if (ret == *len) {
383 size_t size;
384 *string = strbuf_detach(&buf, &size);
385 *len = size;
386 return (char *)*string;
387 }
388
389 return NULL;
390}
391
392int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
393{
394 char *last_branch = substitute_branch_name(&str, &len);
395 int refs_found = expand_ref(str, len, sha1, ref);
396 free(last_branch);
397 return refs_found;
398}
399
400int expand_ref(const char *str, int len, unsigned char *sha1, char **ref)
401{
402 const char **p, *r;
403 int refs_found = 0;
404
405 *ref = NULL;
406 for (p = ref_rev_parse_rules; *p; p++) {
407 char fullref[PATH_MAX];
408 unsigned char sha1_from_ref[20];
409 unsigned char *this_result;
410 int flag;
411
412 this_result = refs_found ? sha1_from_ref : sha1;
413 mksnpath(fullref, sizeof(fullref), *p, len, str);
414 r = resolve_ref_unsafe(fullref, RESOLVE_REF_READING,
415 this_result, &flag);
416 if (r) {
417 if (!refs_found++)
418 *ref = xstrdup(r);
419 if (!warn_ambiguous_refs)
420 break;
421 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
422 warning("ignoring dangling symref %s.", fullref);
423 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
424 warning("ignoring broken ref %s.", fullref);
425 }
426 }
427 return refs_found;
428}
429
430int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
431{
432 char *last_branch = substitute_branch_name(&str, &len);
433 const char **p;
434 int logs_found = 0;
435
436 *log = NULL;
437 for (p = ref_rev_parse_rules; *p; p++) {
438 unsigned char hash[20];
439 char path[PATH_MAX];
440 const char *ref, *it;
441
442 mksnpath(path, sizeof(path), *p, len, str);
443 ref = resolve_ref_unsafe(path, RESOLVE_REF_READING,
444 hash, NULL);
445 if (!ref)
446 continue;
447 if (reflog_exists(path))
448 it = path;
449 else if (strcmp(ref, path) && reflog_exists(ref))
450 it = ref;
451 else
452 continue;
453 if (!logs_found++) {
454 *log = xstrdup(it);
455 hashcpy(sha1, hash);
456 }
457 if (!warn_ambiguous_refs)
458 break;
459 }
460 free(last_branch);
461 return logs_found;
462}
463
464static int is_per_worktree_ref(const char *refname)
465{
466 return !strcmp(refname, "HEAD") ||
467 starts_with(refname, "refs/bisect/");
468}
469
470static int is_pseudoref_syntax(const char *refname)
471{
472 const char *c;
473
474 for (c = refname; *c; c++) {
475 if (!isupper(*c) && *c != '-' && *c != '_')
476 return 0;
477 }
478
479 return 1;
480}
481
482enum ref_type ref_type(const char *refname)
483{
484 if (is_per_worktree_ref(refname))
485 return REF_TYPE_PER_WORKTREE;
486 if (is_pseudoref_syntax(refname))
487 return REF_TYPE_PSEUDOREF;
488 return REF_TYPE_NORMAL;
489}
490
491static int write_pseudoref(const char *pseudoref, const unsigned char *sha1,
492 const unsigned char *old_sha1, struct strbuf *err)
493{
494 const char *filename;
495 int fd;
496 static struct lock_file lock;
497 struct strbuf buf = STRBUF_INIT;
498 int ret = -1;
499
500 strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
501
502 filename = git_path("%s", pseudoref);
503 fd = hold_lock_file_for_update(&lock, filename, LOCK_DIE_ON_ERROR);
504 if (fd < 0) {
505 strbuf_addf(err, "Could not open '%s' for writing: %s",
506 filename, strerror(errno));
507 return -1;
508 }
509
510 if (old_sha1) {
511 unsigned char actual_old_sha1[20];
512
513 if (read_ref(pseudoref, actual_old_sha1))
514 die("could not read ref '%s'", pseudoref);
515 if (hashcmp(actual_old_sha1, old_sha1)) {
516 strbuf_addf(err, "Unexpected sha1 when writing %s", pseudoref);
517 rollback_lock_file(&lock);
518 goto done;
519 }
520 }
521
522 if (write_in_full(fd, buf.buf, buf.len) != buf.len) {
523 strbuf_addf(err, "Could not write to '%s'", filename);
524 rollback_lock_file(&lock);
525 goto done;
526 }
527
528 commit_lock_file(&lock);
529 ret = 0;
530done:
531 strbuf_release(&buf);
532 return ret;
533}
534
535static int delete_pseudoref(const char *pseudoref, const unsigned char *old_sha1)
536{
537 static struct lock_file lock;
538 const char *filename;
539
540 filename = git_path("%s", pseudoref);
541
542 if (old_sha1 && !is_null_sha1(old_sha1)) {
543 int fd;
544 unsigned char actual_old_sha1[20];
545
546 fd = hold_lock_file_for_update(&lock, filename,
547 LOCK_DIE_ON_ERROR);
548 if (fd < 0)
549 die_errno(_("Could not open '%s' for writing"), filename);
550 if (read_ref(pseudoref, actual_old_sha1))
551 die("could not read ref '%s'", pseudoref);
552 if (hashcmp(actual_old_sha1, old_sha1)) {
553 warning("Unexpected sha1 when deleting %s", pseudoref);
554 rollback_lock_file(&lock);
555 return -1;
556 }
557
558 unlink(filename);
559 rollback_lock_file(&lock);
560 } else {
561 unlink(filename);
562 }
563
564 return 0;
565}
566
567int delete_ref(const char *refname, const unsigned char *old_sha1,
568 unsigned int flags)
569{
570 struct ref_transaction *transaction;
571 struct strbuf err = STRBUF_INIT;
572
573 if (ref_type(refname) == REF_TYPE_PSEUDOREF)
574 return delete_pseudoref(refname, old_sha1);
575
576 transaction = ref_transaction_begin(&err);
577 if (!transaction ||
578 ref_transaction_delete(transaction, refname, old_sha1,
579 flags, NULL, &err) ||
580 ref_transaction_commit(transaction, &err)) {
581 error("%s", err.buf);
582 ref_transaction_free(transaction);
583 strbuf_release(&err);
584 return 1;
585 }
586 ref_transaction_free(transaction);
587 strbuf_release(&err);
588 return 0;
589}
590
591int copy_reflog_msg(char *buf, const char *msg)
592{
593 char *cp = buf;
594 char c;
595 int wasspace = 1;
596
597 *cp++ = '\t';
598 while ((c = *msg++)) {
599 if (wasspace && isspace(c))
600 continue;
601 wasspace = isspace(c);
602 if (wasspace)
603 c = ' ';
604 *cp++ = c;
605 }
606 while (buf < cp && isspace(cp[-1]))
607 cp--;
608 *cp++ = '\n';
609 return cp - buf;
610}
611
612int should_autocreate_reflog(const char *refname)
613{
614 if (!log_all_ref_updates)
615 return 0;
616 return starts_with(refname, "refs/heads/") ||
617 starts_with(refname, "refs/remotes/") ||
618 starts_with(refname, "refs/notes/") ||
619 !strcmp(refname, "HEAD");
620}
621
622int is_branch(const char *refname)
623{
624 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
625}
626
627struct read_ref_at_cb {
628 const char *refname;
629 unsigned long at_time;
630 int cnt;
631 int reccnt;
632 unsigned char *sha1;
633 int found_it;
634
635 unsigned char osha1[20];
636 unsigned char nsha1[20];
637 int tz;
638 unsigned long date;
639 char **msg;
640 unsigned long *cutoff_time;
641 int *cutoff_tz;
642 int *cutoff_cnt;
643};
644
645static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1,
646 const char *email, unsigned long timestamp, int tz,
647 const char *message, void *cb_data)
648{
649 struct read_ref_at_cb *cb = cb_data;
650
651 cb->reccnt++;
652 cb->tz = tz;
653 cb->date = timestamp;
654
655 if (timestamp <= cb->at_time || cb->cnt == 0) {
656 if (cb->msg)
657 *cb->msg = xstrdup(message);
658 if (cb->cutoff_time)
659 *cb->cutoff_time = timestamp;
660 if (cb->cutoff_tz)
661 *cb->cutoff_tz = tz;
662 if (cb->cutoff_cnt)
663 *cb->cutoff_cnt = cb->reccnt - 1;
664 /*
665 * we have not yet updated cb->[n|o]sha1 so they still
666 * hold the values for the previous record.
667 */
668 if (!is_null_sha1(cb->osha1)) {
669 hashcpy(cb->sha1, nsha1);
670 if (hashcmp(cb->osha1, nsha1))
671 warning("Log for ref %s has gap after %s.",
672 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
673 }
674 else if (cb->date == cb->at_time)
675 hashcpy(cb->sha1, nsha1);
676 else if (hashcmp(nsha1, cb->sha1))
677 warning("Log for ref %s unexpectedly ended on %s.",
678 cb->refname, show_date(cb->date, cb->tz,
679 DATE_MODE(RFC2822)));
680 hashcpy(cb->osha1, osha1);
681 hashcpy(cb->nsha1, nsha1);
682 cb->found_it = 1;
683 return 1;
684 }
685 hashcpy(cb->osha1, osha1);
686 hashcpy(cb->nsha1, nsha1);
687 if (cb->cnt > 0)
688 cb->cnt--;
689 return 0;
690}
691
692static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1,
693 const char *email, unsigned long timestamp,
694 int tz, const char *message, void *cb_data)
695{
696 struct read_ref_at_cb *cb = cb_data;
697
698 if (cb->msg)
699 *cb->msg = xstrdup(message);
700 if (cb->cutoff_time)
701 *cb->cutoff_time = timestamp;
702 if (cb->cutoff_tz)
703 *cb->cutoff_tz = tz;
704 if (cb->cutoff_cnt)
705 *cb->cutoff_cnt = cb->reccnt;
706 hashcpy(cb->sha1, osha1);
707 if (is_null_sha1(cb->sha1))
708 hashcpy(cb->sha1, nsha1);
709 /* We just want the first entry */
710 return 1;
711}
712
713int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, int cnt,
714 unsigned char *sha1, char **msg,
715 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
716{
717 struct read_ref_at_cb cb;
718
719 memset(&cb, 0, sizeof(cb));
720 cb.refname = refname;
721 cb.at_time = at_time;
722 cb.cnt = cnt;
723 cb.msg = msg;
724 cb.cutoff_time = cutoff_time;
725 cb.cutoff_tz = cutoff_tz;
726 cb.cutoff_cnt = cutoff_cnt;
727 cb.sha1 = sha1;
728
729 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
730
731 if (!cb.reccnt) {
732 if (flags & GET_SHA1_QUIETLY)
733 exit(128);
734 else
735 die("Log for %s is empty.", refname);
736 }
737 if (cb.found_it)
738 return 0;
739
740 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
741
742 return 1;
743}
744
745struct ref_transaction *ref_transaction_begin(struct strbuf *err)
746{
747 assert(err);
748
749 return xcalloc(1, sizeof(struct ref_transaction));
750}
751
752void ref_transaction_free(struct ref_transaction *transaction)
753{
754 int i;
755
756 if (!transaction)
757 return;
758
759 for (i = 0; i < transaction->nr; i++) {
760 free(transaction->updates[i]->msg);
761 free(transaction->updates[i]);
762 }
763 free(transaction->updates);
764 free(transaction);
765}
766
767static struct ref_update *add_update(struct ref_transaction *transaction,
768 const char *refname)
769{
770 size_t len = strlen(refname) + 1;
771 struct ref_update *update = xcalloc(1, sizeof(*update) + len);
772
773 memcpy((char *)update->refname, refname, len); /* includes NUL */
774 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
775 transaction->updates[transaction->nr++] = update;
776 return update;
777}
778
779int ref_transaction_update(struct ref_transaction *transaction,
780 const char *refname,
781 const unsigned char *new_sha1,
782 const unsigned char *old_sha1,
783 unsigned int flags, const char *msg,
784 struct strbuf *err)
785{
786 struct ref_update *update;
787
788 assert(err);
789
790 if (transaction->state != REF_TRANSACTION_OPEN)
791 die("BUG: update called for transaction that is not open");
792
793 if (new_sha1 && !is_null_sha1(new_sha1) &&
794 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
795 strbuf_addf(err, "refusing to update ref with bad name %s",
796 refname);
797 return -1;
798 }
799
800 update = add_update(transaction, refname);
801 if (new_sha1) {
802 hashcpy(update->new_sha1, new_sha1);
803 flags |= REF_HAVE_NEW;
804 }
805 if (old_sha1) {
806 hashcpy(update->old_sha1, old_sha1);
807 flags |= REF_HAVE_OLD;
808 }
809 update->flags = flags;
810 if (msg)
811 update->msg = xstrdup(msg);
812 return 0;
813}
814
815int ref_transaction_create(struct ref_transaction *transaction,
816 const char *refname,
817 const unsigned char *new_sha1,
818 unsigned int flags, const char *msg,
819 struct strbuf *err)
820{
821 if (!new_sha1 || is_null_sha1(new_sha1))
822 die("BUG: create called without valid new_sha1");
823 return ref_transaction_update(transaction, refname, new_sha1,
824 null_sha1, flags, msg, err);
825}
826
827int ref_transaction_delete(struct ref_transaction *transaction,
828 const char *refname,
829 const unsigned char *old_sha1,
830 unsigned int flags, const char *msg,
831 struct strbuf *err)
832{
833 if (old_sha1 && is_null_sha1(old_sha1))
834 die("BUG: delete called with old_sha1 set to zeros");
835 return ref_transaction_update(transaction, refname,
836 null_sha1, old_sha1,
837 flags, msg, err);
838}
839
840int ref_transaction_verify(struct ref_transaction *transaction,
841 const char *refname,
842 const unsigned char *old_sha1,
843 unsigned int flags,
844 struct strbuf *err)
845{
846 if (!old_sha1)
847 die("BUG: verify called with old_sha1 set to NULL");
848 return ref_transaction_update(transaction, refname,
849 NULL, old_sha1,
850 flags, NULL, err);
851}
852
853int update_ref(const char *msg, const char *refname,
854 const unsigned char *new_sha1, const unsigned char *old_sha1,
855 unsigned int flags, enum action_on_err onerr)
856{
857 struct ref_transaction *t = NULL;
858 struct strbuf err = STRBUF_INIT;
859 int ret = 0;
860
861 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
862 ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
863 } else {
864 t = ref_transaction_begin(&err);
865 if (!t ||
866 ref_transaction_update(t, refname, new_sha1, old_sha1,
867 flags, msg, &err) ||
868 ref_transaction_commit(t, &err)) {
869 ret = 1;
870 ref_transaction_free(t);
871 }
872 }
873 if (ret) {
874 const char *str = "update_ref failed for ref '%s': %s";
875
876 switch (onerr) {
877 case UPDATE_REFS_MSG_ON_ERR:
878 error(str, refname, err.buf);
879 break;
880 case UPDATE_REFS_DIE_ON_ERR:
881 die(str, refname, err.buf);
882 break;
883 case UPDATE_REFS_QUIET_ON_ERR:
884 break;
885 }
886 strbuf_release(&err);
887 return 1;
888 }
889 strbuf_release(&err);
890 if (t)
891 ref_transaction_free(t);
892 return 0;
893}
894
895char *shorten_unambiguous_ref(const char *refname, int strict)
896{
897 int i;
898 static char **scanf_fmts;
899 static int nr_rules;
900 char *short_name;
901
902 if (!nr_rules) {
903 /*
904 * Pre-generate scanf formats from ref_rev_parse_rules[].
905 * Generate a format suitable for scanf from a
906 * ref_rev_parse_rules rule by interpolating "%s" at the
907 * location of the "%.*s".
908 */
909 size_t total_len = 0;
910 size_t offset = 0;
911
912 /* the rule list is NULL terminated, count them first */
913 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
914 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
915 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
916
917 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
918
919 offset = 0;
920 for (i = 0; i < nr_rules; i++) {
921 assert(offset < total_len);
922 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
923 offset += snprintf(scanf_fmts[i], total_len - offset,
924 ref_rev_parse_rules[i], 2, "%s") + 1;
925 }
926 }
927
928 /* bail out if there are no rules */
929 if (!nr_rules)
930 return xstrdup(refname);
931
932 /* buffer for scanf result, at most refname must fit */
933 short_name = xstrdup(refname);
934
935 /* skip first rule, it will always match */
936 for (i = nr_rules - 1; i > 0 ; --i) {
937 int j;
938 int rules_to_fail = i;
939 int short_name_len;
940
941 if (1 != sscanf(refname, scanf_fmts[i], short_name))
942 continue;
943
944 short_name_len = strlen(short_name);
945
946 /*
947 * in strict mode, all (except the matched one) rules
948 * must fail to resolve to a valid non-ambiguous ref
949 */
950 if (strict)
951 rules_to_fail = nr_rules;
952
953 /*
954 * check if the short name resolves to a valid ref,
955 * but use only rules prior to the matched one
956 */
957 for (j = 0; j < rules_to_fail; j++) {
958 const char *rule = ref_rev_parse_rules[j];
959 char refname[PATH_MAX];
960
961 /* skip matched rule */
962 if (i == j)
963 continue;
964
965 /*
966 * the short name is ambiguous, if it resolves
967 * (with this previous rule) to a valid ref
968 * read_ref() returns 0 on success
969 */
970 mksnpath(refname, sizeof(refname),
971 rule, short_name_len, short_name);
972 if (ref_exists(refname))
973 break;
974 }
975
976 /*
977 * short name is non-ambiguous if all previous rules
978 * haven't resolved to a valid ref
979 */
980 if (j == rules_to_fail)
981 return short_name;
982 }
983
984 free(short_name);
985 return xstrdup(refname);
986}
987
988static struct string_list *hide_refs;
989
990int parse_hide_refs_config(const char *var, const char *value, const char *section)
991{
992 if (!strcmp("transfer.hiderefs", var) ||
993 /* NEEDSWORK: use parse_config_key() once both are merged */
994 (starts_with(var, section) && var[strlen(section)] == '.' &&
995 !strcmp(var + strlen(section), ".hiderefs"))) {
996 char *ref;
997 int len;
998
999 if (!value)
1000 return config_error_nonbool(var);
1001 ref = xstrdup(value);
1002 len = strlen(ref);
1003 while (len && ref[len - 1] == '/')
1004 ref[--len] = '\0';
1005 if (!hide_refs) {
1006 hide_refs = xcalloc(1, sizeof(*hide_refs));
1007 hide_refs->strdup_strings = 1;
1008 }
1009 string_list_append(hide_refs, ref);
1010 }
1011 return 0;
1012}
1013
1014int ref_is_hidden(const char *refname, const char *refname_full)
1015{
1016 int i;
1017
1018 if (!hide_refs)
1019 return 0;
1020 for (i = hide_refs->nr - 1; i >= 0; i--) {
1021 const char *match = hide_refs->items[i].string;
1022 const char *subject;
1023 int neg = 0;
1024 int len;
1025
1026 if (*match == '!') {
1027 neg = 1;
1028 match++;
1029 }
1030
1031 if (*match == '^') {
1032 subject = refname_full;
1033 match++;
1034 } else {
1035 subject = refname;
1036 }
1037
1038 /* refname can be NULL when namespaces are used. */
1039 if (!subject || !starts_with(subject, match))
1040 continue;
1041 len = strlen(match);
1042 if (!subject[len] || subject[len] == '/')
1043 return !neg;
1044 }
1045 return 0;
1046}
1047
1048const char *find_descendant_ref(const char *dirname,
1049 const struct string_list *extras,
1050 const struct string_list *skip)
1051{
1052 int pos;
1053
1054 if (!extras)
1055 return NULL;
1056
1057 /*
1058 * Look at the place where dirname would be inserted into
1059 * extras. If there is an entry at that position that starts
1060 * with dirname (remember, dirname includes the trailing
1061 * slash) and is not in skip, then we have a conflict.
1062 */
1063 for (pos = string_list_find_insert_index(extras, dirname, 0);
1064 pos < extras->nr; pos++) {
1065 const char *extra_refname = extras->items[pos].string;
1066
1067 if (!starts_with(extra_refname, dirname))
1068 break;
1069
1070 if (!skip || !string_list_has_string(skip, extra_refname))
1071 return extra_refname;
1072 }
1073 return NULL;
1074}
1075
1076int rename_ref_available(const char *oldname, const char *newname)
1077{
1078 struct string_list skip = STRING_LIST_INIT_NODUP;
1079 struct strbuf err = STRBUF_INIT;
1080 int ret;
1081
1082 string_list_insert(&skip, oldname);
1083 ret = !verify_refname_available(newname, NULL, &skip, &err);
1084 if (!ret)
1085 error("%s", err.buf);
1086
1087 string_list_clear(&skip, 0);
1088 strbuf_release(&err);
1089 return ret;
1090}