]> git.ipfire.org Git - thirdparty/git.git/blob - refs.c
Merge branch 'tb/complete-word-diff-regex'
[thirdparty/git.git] / refs.c
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 */
22 static 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 */
48 static 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 }
82 out:
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
93 int 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
121 int 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
145 char *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 */
153 struct ref_filter {
154 const char *pattern;
155 each_ref_fn *fn;
156 void *cb_data;
157 };
158
159 int 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
166 int read_ref(const char *refname, unsigned char *sha1)
167 {
168 return read_ref_full(refname, RESOLVE_REF_READING, sha1, NULL);
169 }
170
171 int ref_exists(const char *refname)
172 {
173 unsigned char sha1[20];
174 return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, sha1, NULL);
175 }
176
177 static 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
187 enum 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
208 struct warn_if_dangling_data {
209 FILE *fp;
210 const char *refname;
211 const struct string_list *refnames;
212 const char *msg_fmt;
213 };
214
215 static 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
238 void 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
249 void 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
260 int 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
265 int 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
270 int 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
275 int 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
280 int 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
285 int 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
290 int 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
305 int 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
334 int 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
339 const 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
348 static 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
358 int 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 */
377 static 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
392 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
393 {
394 char *last_branch = substitute_branch_name(&str, &len);
395 const char **p, *r;
396 int refs_found = 0;
397
398 *ref = NULL;
399 for (p = ref_rev_parse_rules; *p; p++) {
400 char fullref[PATH_MAX];
401 unsigned char sha1_from_ref[20];
402 unsigned char *this_result;
403 int flag;
404
405 this_result = refs_found ? sha1_from_ref : sha1;
406 mksnpath(fullref, sizeof(fullref), *p, len, str);
407 r = resolve_ref_unsafe(fullref, RESOLVE_REF_READING,
408 this_result, &flag);
409 if (r) {
410 if (!refs_found++)
411 *ref = xstrdup(r);
412 if (!warn_ambiguous_refs)
413 break;
414 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
415 warning("ignoring dangling symref %s.", fullref);
416 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
417 warning("ignoring broken ref %s.", fullref);
418 }
419 }
420 free(last_branch);
421 return refs_found;
422 }
423
424 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
425 {
426 char *last_branch = substitute_branch_name(&str, &len);
427 const char **p;
428 int logs_found = 0;
429
430 *log = NULL;
431 for (p = ref_rev_parse_rules; *p; p++) {
432 unsigned char hash[20];
433 char path[PATH_MAX];
434 const char *ref, *it;
435
436 mksnpath(path, sizeof(path), *p, len, str);
437 ref = resolve_ref_unsafe(path, RESOLVE_REF_READING,
438 hash, NULL);
439 if (!ref)
440 continue;
441 if (reflog_exists(path))
442 it = path;
443 else if (strcmp(ref, path) && reflog_exists(ref))
444 it = ref;
445 else
446 continue;
447 if (!logs_found++) {
448 *log = xstrdup(it);
449 hashcpy(sha1, hash);
450 }
451 if (!warn_ambiguous_refs)
452 break;
453 }
454 free(last_branch);
455 return logs_found;
456 }
457
458 static int is_per_worktree_ref(const char *refname)
459 {
460 return !strcmp(refname, "HEAD") ||
461 starts_with(refname, "refs/bisect/");
462 }
463
464 static int is_pseudoref_syntax(const char *refname)
465 {
466 const char *c;
467
468 for (c = refname; *c; c++) {
469 if (!isupper(*c) && *c != '-' && *c != '_')
470 return 0;
471 }
472
473 return 1;
474 }
475
476 enum ref_type ref_type(const char *refname)
477 {
478 if (is_per_worktree_ref(refname))
479 return REF_TYPE_PER_WORKTREE;
480 if (is_pseudoref_syntax(refname))
481 return REF_TYPE_PSEUDOREF;
482 return REF_TYPE_NORMAL;
483 }
484
485 static int write_pseudoref(const char *pseudoref, const unsigned char *sha1,
486 const unsigned char *old_sha1, struct strbuf *err)
487 {
488 const char *filename;
489 int fd;
490 static struct lock_file lock;
491 struct strbuf buf = STRBUF_INIT;
492 int ret = -1;
493
494 strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
495
496 filename = git_path("%s", pseudoref);
497 fd = hold_lock_file_for_update(&lock, filename, LOCK_DIE_ON_ERROR);
498 if (fd < 0) {
499 strbuf_addf(err, "Could not open '%s' for writing: %s",
500 filename, strerror(errno));
501 return -1;
502 }
503
504 if (old_sha1) {
505 unsigned char actual_old_sha1[20];
506
507 if (read_ref(pseudoref, actual_old_sha1))
508 die("could not read ref '%s'", pseudoref);
509 if (hashcmp(actual_old_sha1, old_sha1)) {
510 strbuf_addf(err, "Unexpected sha1 when writing %s", pseudoref);
511 rollback_lock_file(&lock);
512 goto done;
513 }
514 }
515
516 if (write_in_full(fd, buf.buf, buf.len) != buf.len) {
517 strbuf_addf(err, "Could not write to '%s'", filename);
518 rollback_lock_file(&lock);
519 goto done;
520 }
521
522 commit_lock_file(&lock);
523 ret = 0;
524 done:
525 strbuf_release(&buf);
526 return ret;
527 }
528
529 static int delete_pseudoref(const char *pseudoref, const unsigned char *old_sha1)
530 {
531 static struct lock_file lock;
532 const char *filename;
533
534 filename = git_path("%s", pseudoref);
535
536 if (old_sha1 && !is_null_sha1(old_sha1)) {
537 int fd;
538 unsigned char actual_old_sha1[20];
539
540 fd = hold_lock_file_for_update(&lock, filename,
541 LOCK_DIE_ON_ERROR);
542 if (fd < 0)
543 die_errno(_("Could not open '%s' for writing"), filename);
544 if (read_ref(pseudoref, actual_old_sha1))
545 die("could not read ref '%s'", pseudoref);
546 if (hashcmp(actual_old_sha1, old_sha1)) {
547 warning("Unexpected sha1 when deleting %s", pseudoref);
548 rollback_lock_file(&lock);
549 return -1;
550 }
551
552 unlink(filename);
553 rollback_lock_file(&lock);
554 } else {
555 unlink(filename);
556 }
557
558 return 0;
559 }
560
561 int delete_ref(const char *refname, const unsigned char *old_sha1,
562 unsigned int flags)
563 {
564 struct ref_transaction *transaction;
565 struct strbuf err = STRBUF_INIT;
566
567 if (ref_type(refname) == REF_TYPE_PSEUDOREF)
568 return delete_pseudoref(refname, old_sha1);
569
570 transaction = ref_transaction_begin(&err);
571 if (!transaction ||
572 ref_transaction_delete(transaction, refname, old_sha1,
573 flags, NULL, &err) ||
574 ref_transaction_commit(transaction, &err)) {
575 error("%s", err.buf);
576 ref_transaction_free(transaction);
577 strbuf_release(&err);
578 return 1;
579 }
580 ref_transaction_free(transaction);
581 strbuf_release(&err);
582 return 0;
583 }
584
585 int copy_reflog_msg(char *buf, const char *msg)
586 {
587 char *cp = buf;
588 char c;
589 int wasspace = 1;
590
591 *cp++ = '\t';
592 while ((c = *msg++)) {
593 if (wasspace && isspace(c))
594 continue;
595 wasspace = isspace(c);
596 if (wasspace)
597 c = ' ';
598 *cp++ = c;
599 }
600 while (buf < cp && isspace(cp[-1]))
601 cp--;
602 *cp++ = '\n';
603 return cp - buf;
604 }
605
606 int should_autocreate_reflog(const char *refname)
607 {
608 if (!log_all_ref_updates)
609 return 0;
610 return starts_with(refname, "refs/heads/") ||
611 starts_with(refname, "refs/remotes/") ||
612 starts_with(refname, "refs/notes/") ||
613 !strcmp(refname, "HEAD");
614 }
615
616 int is_branch(const char *refname)
617 {
618 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
619 }
620
621 struct read_ref_at_cb {
622 const char *refname;
623 unsigned long at_time;
624 int cnt;
625 int reccnt;
626 unsigned char *sha1;
627 int found_it;
628
629 unsigned char osha1[20];
630 unsigned char nsha1[20];
631 int tz;
632 unsigned long date;
633 char **msg;
634 unsigned long *cutoff_time;
635 int *cutoff_tz;
636 int *cutoff_cnt;
637 };
638
639 static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1,
640 const char *email, unsigned long timestamp, int tz,
641 const char *message, void *cb_data)
642 {
643 struct read_ref_at_cb *cb = cb_data;
644
645 cb->reccnt++;
646 cb->tz = tz;
647 cb->date = timestamp;
648
649 if (timestamp <= cb->at_time || cb->cnt == 0) {
650 if (cb->msg)
651 *cb->msg = xstrdup(message);
652 if (cb->cutoff_time)
653 *cb->cutoff_time = timestamp;
654 if (cb->cutoff_tz)
655 *cb->cutoff_tz = tz;
656 if (cb->cutoff_cnt)
657 *cb->cutoff_cnt = cb->reccnt - 1;
658 /*
659 * we have not yet updated cb->[n|o]sha1 so they still
660 * hold the values for the previous record.
661 */
662 if (!is_null_sha1(cb->osha1)) {
663 hashcpy(cb->sha1, nsha1);
664 if (hashcmp(cb->osha1, nsha1))
665 warning("Log for ref %s has gap after %s.",
666 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
667 }
668 else if (cb->date == cb->at_time)
669 hashcpy(cb->sha1, nsha1);
670 else if (hashcmp(nsha1, cb->sha1))
671 warning("Log for ref %s unexpectedly ended on %s.",
672 cb->refname, show_date(cb->date, cb->tz,
673 DATE_MODE(RFC2822)));
674 hashcpy(cb->osha1, osha1);
675 hashcpy(cb->nsha1, nsha1);
676 cb->found_it = 1;
677 return 1;
678 }
679 hashcpy(cb->osha1, osha1);
680 hashcpy(cb->nsha1, nsha1);
681 if (cb->cnt > 0)
682 cb->cnt--;
683 return 0;
684 }
685
686 static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1,
687 const char *email, unsigned long timestamp,
688 int tz, const char *message, void *cb_data)
689 {
690 struct read_ref_at_cb *cb = cb_data;
691
692 if (cb->msg)
693 *cb->msg = xstrdup(message);
694 if (cb->cutoff_time)
695 *cb->cutoff_time = timestamp;
696 if (cb->cutoff_tz)
697 *cb->cutoff_tz = tz;
698 if (cb->cutoff_cnt)
699 *cb->cutoff_cnt = cb->reccnt;
700 hashcpy(cb->sha1, osha1);
701 if (is_null_sha1(cb->sha1))
702 hashcpy(cb->sha1, nsha1);
703 /* We just want the first entry */
704 return 1;
705 }
706
707 int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, int cnt,
708 unsigned char *sha1, char **msg,
709 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
710 {
711 struct read_ref_at_cb cb;
712
713 memset(&cb, 0, sizeof(cb));
714 cb.refname = refname;
715 cb.at_time = at_time;
716 cb.cnt = cnt;
717 cb.msg = msg;
718 cb.cutoff_time = cutoff_time;
719 cb.cutoff_tz = cutoff_tz;
720 cb.cutoff_cnt = cutoff_cnt;
721 cb.sha1 = sha1;
722
723 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
724
725 if (!cb.reccnt) {
726 if (flags & GET_SHA1_QUIETLY)
727 exit(128);
728 else
729 die("Log for %s is empty.", refname);
730 }
731 if (cb.found_it)
732 return 0;
733
734 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
735
736 return 1;
737 }
738
739 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
740 {
741 assert(err);
742
743 return xcalloc(1, sizeof(struct ref_transaction));
744 }
745
746 void ref_transaction_free(struct ref_transaction *transaction)
747 {
748 int i;
749
750 if (!transaction)
751 return;
752
753 for (i = 0; i < transaction->nr; i++) {
754 free(transaction->updates[i]->msg);
755 free(transaction->updates[i]);
756 }
757 free(transaction->updates);
758 free(transaction);
759 }
760
761 static struct ref_update *add_update(struct ref_transaction *transaction,
762 const char *refname)
763 {
764 size_t len = strlen(refname) + 1;
765 struct ref_update *update = xcalloc(1, sizeof(*update) + len);
766
767 memcpy((char *)update->refname, refname, len); /* includes NUL */
768 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
769 transaction->updates[transaction->nr++] = update;
770 return update;
771 }
772
773 int ref_transaction_update(struct ref_transaction *transaction,
774 const char *refname,
775 const unsigned char *new_sha1,
776 const unsigned char *old_sha1,
777 unsigned int flags, const char *msg,
778 struct strbuf *err)
779 {
780 struct ref_update *update;
781
782 assert(err);
783
784 if (transaction->state != REF_TRANSACTION_OPEN)
785 die("BUG: update called for transaction that is not open");
786
787 if (new_sha1 && !is_null_sha1(new_sha1) &&
788 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
789 strbuf_addf(err, "refusing to update ref with bad name %s",
790 refname);
791 return -1;
792 }
793
794 update = add_update(transaction, refname);
795 if (new_sha1) {
796 hashcpy(update->new_sha1, new_sha1);
797 flags |= REF_HAVE_NEW;
798 }
799 if (old_sha1) {
800 hashcpy(update->old_sha1, old_sha1);
801 flags |= REF_HAVE_OLD;
802 }
803 update->flags = flags;
804 if (msg)
805 update->msg = xstrdup(msg);
806 return 0;
807 }
808
809 int ref_transaction_create(struct ref_transaction *transaction,
810 const char *refname,
811 const unsigned char *new_sha1,
812 unsigned int flags, const char *msg,
813 struct strbuf *err)
814 {
815 if (!new_sha1 || is_null_sha1(new_sha1))
816 die("BUG: create called without valid new_sha1");
817 return ref_transaction_update(transaction, refname, new_sha1,
818 null_sha1, flags, msg, err);
819 }
820
821 int ref_transaction_delete(struct ref_transaction *transaction,
822 const char *refname,
823 const unsigned char *old_sha1,
824 unsigned int flags, const char *msg,
825 struct strbuf *err)
826 {
827 if (old_sha1 && is_null_sha1(old_sha1))
828 die("BUG: delete called with old_sha1 set to zeros");
829 return ref_transaction_update(transaction, refname,
830 null_sha1, old_sha1,
831 flags, msg, err);
832 }
833
834 int ref_transaction_verify(struct ref_transaction *transaction,
835 const char *refname,
836 const unsigned char *old_sha1,
837 unsigned int flags,
838 struct strbuf *err)
839 {
840 if (!old_sha1)
841 die("BUG: verify called with old_sha1 set to NULL");
842 return ref_transaction_update(transaction, refname,
843 NULL, old_sha1,
844 flags, NULL, err);
845 }
846
847 int update_ref(const char *msg, const char *refname,
848 const unsigned char *new_sha1, const unsigned char *old_sha1,
849 unsigned int flags, enum action_on_err onerr)
850 {
851 struct ref_transaction *t = NULL;
852 struct strbuf err = STRBUF_INIT;
853 int ret = 0;
854
855 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
856 ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
857 } else {
858 t = ref_transaction_begin(&err);
859 if (!t ||
860 ref_transaction_update(t, refname, new_sha1, old_sha1,
861 flags, msg, &err) ||
862 ref_transaction_commit(t, &err)) {
863 ret = 1;
864 ref_transaction_free(t);
865 }
866 }
867 if (ret) {
868 const char *str = "update_ref failed for ref '%s': %s";
869
870 switch (onerr) {
871 case UPDATE_REFS_MSG_ON_ERR:
872 error(str, refname, err.buf);
873 break;
874 case UPDATE_REFS_DIE_ON_ERR:
875 die(str, refname, err.buf);
876 break;
877 case UPDATE_REFS_QUIET_ON_ERR:
878 break;
879 }
880 strbuf_release(&err);
881 return 1;
882 }
883 strbuf_release(&err);
884 if (t)
885 ref_transaction_free(t);
886 return 0;
887 }
888
889 char *shorten_unambiguous_ref(const char *refname, int strict)
890 {
891 int i;
892 static char **scanf_fmts;
893 static int nr_rules;
894 char *short_name;
895
896 if (!nr_rules) {
897 /*
898 * Pre-generate scanf formats from ref_rev_parse_rules[].
899 * Generate a format suitable for scanf from a
900 * ref_rev_parse_rules rule by interpolating "%s" at the
901 * location of the "%.*s".
902 */
903 size_t total_len = 0;
904 size_t offset = 0;
905
906 /* the rule list is NULL terminated, count them first */
907 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
908 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
909 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
910
911 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
912
913 offset = 0;
914 for (i = 0; i < nr_rules; i++) {
915 assert(offset < total_len);
916 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
917 offset += snprintf(scanf_fmts[i], total_len - offset,
918 ref_rev_parse_rules[i], 2, "%s") + 1;
919 }
920 }
921
922 /* bail out if there are no rules */
923 if (!nr_rules)
924 return xstrdup(refname);
925
926 /* buffer for scanf result, at most refname must fit */
927 short_name = xstrdup(refname);
928
929 /* skip first rule, it will always match */
930 for (i = nr_rules - 1; i > 0 ; --i) {
931 int j;
932 int rules_to_fail = i;
933 int short_name_len;
934
935 if (1 != sscanf(refname, scanf_fmts[i], short_name))
936 continue;
937
938 short_name_len = strlen(short_name);
939
940 /*
941 * in strict mode, all (except the matched one) rules
942 * must fail to resolve to a valid non-ambiguous ref
943 */
944 if (strict)
945 rules_to_fail = nr_rules;
946
947 /*
948 * check if the short name resolves to a valid ref,
949 * but use only rules prior to the matched one
950 */
951 for (j = 0; j < rules_to_fail; j++) {
952 const char *rule = ref_rev_parse_rules[j];
953 char refname[PATH_MAX];
954
955 /* skip matched rule */
956 if (i == j)
957 continue;
958
959 /*
960 * the short name is ambiguous, if it resolves
961 * (with this previous rule) to a valid ref
962 * read_ref() returns 0 on success
963 */
964 mksnpath(refname, sizeof(refname),
965 rule, short_name_len, short_name);
966 if (ref_exists(refname))
967 break;
968 }
969
970 /*
971 * short name is non-ambiguous if all previous rules
972 * haven't resolved to a valid ref
973 */
974 if (j == rules_to_fail)
975 return short_name;
976 }
977
978 free(short_name);
979 return xstrdup(refname);
980 }
981
982 static struct string_list *hide_refs;
983
984 int parse_hide_refs_config(const char *var, const char *value, const char *section)
985 {
986 if (!strcmp("transfer.hiderefs", var) ||
987 /* NEEDSWORK: use parse_config_key() once both are merged */
988 (starts_with(var, section) && var[strlen(section)] == '.' &&
989 !strcmp(var + strlen(section), ".hiderefs"))) {
990 char *ref;
991 int len;
992
993 if (!value)
994 return config_error_nonbool(var);
995 ref = xstrdup(value);
996 len = strlen(ref);
997 while (len && ref[len - 1] == '/')
998 ref[--len] = '\0';
999 if (!hide_refs) {
1000 hide_refs = xcalloc(1, sizeof(*hide_refs));
1001 hide_refs->strdup_strings = 1;
1002 }
1003 string_list_append(hide_refs, ref);
1004 }
1005 return 0;
1006 }
1007
1008 int ref_is_hidden(const char *refname, const char *refname_full)
1009 {
1010 int i;
1011
1012 if (!hide_refs)
1013 return 0;
1014 for (i = hide_refs->nr - 1; i >= 0; i--) {
1015 const char *match = hide_refs->items[i].string;
1016 const char *subject;
1017 int neg = 0;
1018 int len;
1019
1020 if (*match == '!') {
1021 neg = 1;
1022 match++;
1023 }
1024
1025 if (*match == '^') {
1026 subject = refname_full;
1027 match++;
1028 } else {
1029 subject = refname;
1030 }
1031
1032 /* refname can be NULL when namespaces are used. */
1033 if (!subject || !starts_with(subject, match))
1034 continue;
1035 len = strlen(match);
1036 if (!subject[len] || subject[len] == '/')
1037 return !neg;
1038 }
1039 return 0;
1040 }
1041
1042 const char *find_descendant_ref(const char *dirname,
1043 const struct string_list *extras,
1044 const struct string_list *skip)
1045 {
1046 int pos;
1047
1048 if (!extras)
1049 return NULL;
1050
1051 /*
1052 * Look at the place where dirname would be inserted into
1053 * extras. If there is an entry at that position that starts
1054 * with dirname (remember, dirname includes the trailing
1055 * slash) and is not in skip, then we have a conflict.
1056 */
1057 for (pos = string_list_find_insert_index(extras, dirname, 0);
1058 pos < extras->nr; pos++) {
1059 const char *extra_refname = extras->items[pos].string;
1060
1061 if (!starts_with(extra_refname, dirname))
1062 break;
1063
1064 if (!skip || !string_list_has_string(skip, extra_refname))
1065 return extra_refname;
1066 }
1067 return NULL;
1068 }
1069
1070 int rename_ref_available(const char *oldname, const char *newname)
1071 {
1072 struct string_list skip = STRING_LIST_INIT_NODUP;
1073 struct strbuf err = STRBUF_INIT;
1074 int ret;
1075
1076 string_list_insert(&skip, oldname);
1077 ret = !verify_refname_available(newname, NULL, &skip, &err);
1078 if (!ret)
1079 error("%s", err.buf);
1080
1081 string_list_clear(&skip, 0);
1082 strbuf_release(&err);
1083 return ret;
1084 }