for-each-ref: add '--contains' option
[git] / builtin / tag.c
1 /*
2  * Builtin "git tag"
3  *
4  * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>,
5  *                    Carlos Rica <jasampler@gmail.com>
6  * Based on git-tag.sh and mktag.c by Linus Torvalds.
7  */
8
9 #include "cache.h"
10 #include "builtin.h"
11 #include "refs.h"
12 #include "tag.h"
13 #include "run-command.h"
14 #include "parse-options.h"
15 #include "diff.h"
16 #include "revision.h"
17 #include "gpg-interface.h"
18 #include "sha1-array.h"
19 #include "column.h"
20
21 static const char * const git_tag_usage[] = {
22         N_("git tag [-a | -s | -u <key-id>] [-f] [-m <msg> | -F <file>] <tagname> [<head>]"),
23         N_("git tag -d <tagname>..."),
24         N_("git tag -l [-n[<num>]] [--contains <commit>] [--points-at <object>]"
25                 "\n\t\t[<pattern>...]"),
26         N_("git tag -v <tagname>..."),
27         NULL
28 };
29
30 #define STRCMP_SORT     0       /* must be zero */
31 #define VERCMP_SORT     1
32 #define SORT_MASK       0x7fff
33 #define REVERSE_SORT    0x8000
34
35 static int tag_sort;
36
37 struct tag_filter {
38         const char **patterns;
39         int lines;
40         int sort;
41         struct string_list tags;
42         struct commit_list *with_commit;
43 };
44
45 static struct sha1_array points_at;
46 static unsigned int colopts;
47
48 static int match_pattern(const char **patterns, const char *ref)
49 {
50         /* no pattern means match everything */
51         if (!*patterns)
52                 return 1;
53         for (; *patterns; patterns++)
54                 if (!wildmatch(*patterns, ref, 0, NULL))
55                         return 1;
56         return 0;
57 }
58
59 /*
60  * This is currently duplicated in ref-filter.c, and will eventually be
61  * removed as we port tag.c to use the ref-filter APIs.
62  */
63 static const unsigned char *match_points_at(const char *refname,
64                                             const unsigned char *sha1)
65 {
66         const unsigned char *tagged_sha1 = NULL;
67         struct object *obj;
68
69         if (sha1_array_lookup(&points_at, sha1) >= 0)
70                 return sha1;
71         obj = parse_object(sha1);
72         if (!obj)
73                 die(_("malformed object at '%s'"), refname);
74         if (obj->type == OBJ_TAG)
75                 tagged_sha1 = ((struct tag *)obj)->tagged->sha1;
76         if (tagged_sha1 && sha1_array_lookup(&points_at, tagged_sha1) >= 0)
77                 return tagged_sha1;
78         return NULL;
79 }
80
81 static int in_commit_list(const struct commit_list *want, struct commit *c)
82 {
83         for (; want; want = want->next)
84                 if (!hashcmp(want->item->object.sha1, c->object.sha1))
85                         return 1;
86         return 0;
87 }
88
89 /*
90  * The entire code segment for supporting the --contains option has been
91  * copied over to ref-filter.{c,h}. This will be deleted evetually when
92  * we port tag.c to use ref-filter APIs.
93  */
94 enum contains_result {
95         CONTAINS_UNKNOWN = -1,
96         CONTAINS_NO = 0,
97         CONTAINS_YES = 1
98 };
99
100 /*
101  * Test whether the candidate or one of its parents is contained in the list.
102  * Do not recurse to find out, though, but return -1 if inconclusive.
103  */
104 static enum contains_result contains_test(struct commit *candidate,
105                             const struct commit_list *want)
106 {
107         /* was it previously marked as containing a want commit? */
108         if (candidate->object.flags & TMP_MARK)
109                 return 1;
110         /* or marked as not possibly containing a want commit? */
111         if (candidate->object.flags & UNINTERESTING)
112                 return 0;
113         /* or are we it? */
114         if (in_commit_list(want, candidate)) {
115                 candidate->object.flags |= TMP_MARK;
116                 return 1;
117         }
118
119         if (parse_commit(candidate) < 0)
120                 return 0;
121
122         return -1;
123 }
124
125 /*
126  * Mimicking the real stack, this stack lives on the heap, avoiding stack
127  * overflows.
128  *
129  * At each recursion step, the stack items points to the commits whose
130  * ancestors are to be inspected.
131  */
132 struct stack {
133         int nr, alloc;
134         struct stack_entry {
135                 struct commit *commit;
136                 struct commit_list *parents;
137         } *stack;
138 };
139
140 static void push_to_stack(struct commit *candidate, struct stack *stack)
141 {
142         int index = stack->nr++;
143         ALLOC_GROW(stack->stack, stack->nr, stack->alloc);
144         stack->stack[index].commit = candidate;
145         stack->stack[index].parents = candidate->parents;
146 }
147
148 static enum contains_result contains(struct commit *candidate,
149                 const struct commit_list *want)
150 {
151         struct stack stack = { 0, 0, NULL };
152         int result = contains_test(candidate, want);
153
154         if (result != CONTAINS_UNKNOWN)
155                 return result;
156
157         push_to_stack(candidate, &stack);
158         while (stack.nr) {
159                 struct stack_entry *entry = &stack.stack[stack.nr - 1];
160                 struct commit *commit = entry->commit;
161                 struct commit_list *parents = entry->parents;
162
163                 if (!parents) {
164                         commit->object.flags |= UNINTERESTING;
165                         stack.nr--;
166                 }
167                 /*
168                  * If we just popped the stack, parents->item has been marked,
169                  * therefore contains_test will return a meaningful 0 or 1.
170                  */
171                 else switch (contains_test(parents->item, want)) {
172                 case CONTAINS_YES:
173                         commit->object.flags |= TMP_MARK;
174                         stack.nr--;
175                         break;
176                 case CONTAINS_NO:
177                         entry->parents = parents->next;
178                         break;
179                 case CONTAINS_UNKNOWN:
180                         push_to_stack(parents->item, &stack);
181                         break;
182                 }
183         }
184         free(stack.stack);
185         return contains_test(candidate, want);
186 }
187
188 static void show_tag_lines(const struct object_id *oid, int lines)
189 {
190         int i;
191         unsigned long size;
192         enum object_type type;
193         char *buf, *sp, *eol;
194         size_t len;
195
196         buf = read_sha1_file(oid->hash, &type, &size);
197         if (!buf)
198                 die_errno("unable to read object %s", oid_to_hex(oid));
199         if (type != OBJ_COMMIT && type != OBJ_TAG)
200                 goto free_return;
201         if (!size)
202                 die("an empty %s object %s?",
203                     typename(type), oid_to_hex(oid));
204
205         /* skip header */
206         sp = strstr(buf, "\n\n");
207         if (!sp)
208                 goto free_return;
209
210         /* only take up to "lines" lines, and strip the signature from a tag */
211         if (type == OBJ_TAG)
212                 size = parse_signature(buf, size);
213         for (i = 0, sp += 2; i < lines && sp < buf + size; i++) {
214                 if (i)
215                         printf("\n    ");
216                 eol = memchr(sp, '\n', size - (sp - buf));
217                 len = eol ? eol - sp : size - (sp - buf);
218                 fwrite(sp, len, 1, stdout);
219                 if (!eol)
220                         break;
221                 sp = eol + 1;
222         }
223 free_return:
224         free(buf);
225 }
226
227 static int show_reference(const char *refname, const struct object_id *oid,
228                           int flag, void *cb_data)
229 {
230         struct tag_filter *filter = cb_data;
231
232         if (match_pattern(filter->patterns, refname)) {
233                 if (filter->with_commit) {
234                         struct commit *commit;
235
236                         commit = lookup_commit_reference_gently(oid->hash, 1);
237                         if (!commit)
238                                 return 0;
239                         if (!contains(commit, filter->with_commit))
240                                 return 0;
241                 }
242
243                 if (points_at.nr && !match_points_at(refname, oid->hash))
244                         return 0;
245
246                 if (!filter->lines) {
247                         if (filter->sort)
248                                 string_list_append(&filter->tags, refname);
249                         else
250                                 printf("%s\n", refname);
251                         return 0;
252                 }
253                 printf("%-15s ", refname);
254                 show_tag_lines(oid, filter->lines);
255                 putchar('\n');
256         }
257
258         return 0;
259 }
260
261 static int sort_by_version(const void *a_, const void *b_)
262 {
263         const struct string_list_item *a = a_;
264         const struct string_list_item *b = b_;
265         return versioncmp(a->string, b->string);
266 }
267
268 static int list_tags(const char **patterns, int lines,
269                      struct commit_list *with_commit, int sort)
270 {
271         struct tag_filter filter;
272
273         filter.patterns = patterns;
274         filter.lines = lines;
275         filter.sort = sort;
276         filter.with_commit = with_commit;
277         memset(&filter.tags, 0, sizeof(filter.tags));
278         filter.tags.strdup_strings = 1;
279
280         for_each_tag_ref(show_reference, (void *)&filter);
281         if (sort) {
282                 int i;
283                 if ((sort & SORT_MASK) == VERCMP_SORT)
284                         qsort(filter.tags.items, filter.tags.nr,
285                               sizeof(struct string_list_item), sort_by_version);
286                 if (sort & REVERSE_SORT)
287                         for (i = filter.tags.nr - 1; i >= 0; i--)
288                                 printf("%s\n", filter.tags.items[i].string);
289                 else
290                         for (i = 0; i < filter.tags.nr; i++)
291                                 printf("%s\n", filter.tags.items[i].string);
292                 string_list_clear(&filter.tags, 0);
293         }
294         return 0;
295 }
296
297 typedef int (*each_tag_name_fn)(const char *name, const char *ref,
298                                 const unsigned char *sha1);
299
300 static int for_each_tag_name(const char **argv, each_tag_name_fn fn)
301 {
302         const char **p;
303         char ref[PATH_MAX];
304         int had_error = 0;
305         unsigned char sha1[20];
306
307         for (p = argv; *p; p++) {
308                 if (snprintf(ref, sizeof(ref), "refs/tags/%s", *p)
309                                         >= sizeof(ref)) {
310                         error(_("tag name too long: %.*s..."), 50, *p);
311                         had_error = 1;
312                         continue;
313                 }
314                 if (read_ref(ref, sha1)) {
315                         error(_("tag '%s' not found."), *p);
316                         had_error = 1;
317                         continue;
318                 }
319                 if (fn(*p, ref, sha1))
320                         had_error = 1;
321         }
322         return had_error;
323 }
324
325 static int delete_tag(const char *name, const char *ref,
326                                 const unsigned char *sha1)
327 {
328         if (delete_ref(ref, sha1, 0))
329                 return 1;
330         printf(_("Deleted tag '%s' (was %s)\n"), name, find_unique_abbrev(sha1, DEFAULT_ABBREV));
331         return 0;
332 }
333
334 static int verify_tag(const char *name, const char *ref,
335                                 const unsigned char *sha1)
336 {
337         const char *argv_verify_tag[] = {"verify-tag",
338                                         "-v", "SHA1_HEX", NULL};
339         argv_verify_tag[2] = sha1_to_hex(sha1);
340
341         if (run_command_v_opt(argv_verify_tag, RUN_GIT_CMD))
342                 return error(_("could not verify the tag '%s'"), name);
343         return 0;
344 }
345
346 static int do_sign(struct strbuf *buffer)
347 {
348         return sign_buffer(buffer, buffer, get_signing_key());
349 }
350
351 static const char tag_template[] =
352         N_("\nWrite a message for tag:\n  %s\n"
353         "Lines starting with '%c' will be ignored.\n");
354
355 static const char tag_template_nocleanup[] =
356         N_("\nWrite a message for tag:\n  %s\n"
357         "Lines starting with '%c' will be kept; you may remove them"
358         " yourself if you want to.\n");
359
360 /*
361  * Parse a sort string, and return 0 if parsed successfully. Will return
362  * non-zero when the sort string does not parse into a known type. If var is
363  * given, the error message becomes a warning and includes information about
364  * the configuration value.
365  */
366 static int parse_sort_string(const char *var, const char *arg, int *sort)
367 {
368         int type = 0, flags = 0;
369
370         if (skip_prefix(arg, "-", &arg))
371                 flags |= REVERSE_SORT;
372
373         if (skip_prefix(arg, "version:", &arg) || skip_prefix(arg, "v:", &arg))
374                 type = VERCMP_SORT;
375         else
376                 type = STRCMP_SORT;
377
378         if (strcmp(arg, "refname")) {
379                 if (!var)
380                         return error(_("unsupported sort specification '%s'"), arg);
381                 else {
382                         warning(_("unsupported sort specification '%s' in variable '%s'"),
383                                 var, arg);
384                         return -1;
385                 }
386         }
387
388         *sort = (type | flags);
389
390         return 0;
391 }
392
393 static int git_tag_config(const char *var, const char *value, void *cb)
394 {
395         int status;
396
397         if (!strcmp(var, "tag.sort")) {
398                 if (!value)
399                         return config_error_nonbool(var);
400                 parse_sort_string(var, value, &tag_sort);
401                 return 0;
402         }
403
404         status = git_gpg_config(var, value, cb);
405         if (status)
406                 return status;
407         if (starts_with(var, "column."))
408                 return git_column_config(var, value, "tag", &colopts);
409         return git_default_config(var, value, cb);
410 }
411
412 static void write_tag_body(int fd, const unsigned char *sha1)
413 {
414         unsigned long size;
415         enum object_type type;
416         char *buf, *sp;
417
418         buf = read_sha1_file(sha1, &type, &size);
419         if (!buf)
420                 return;
421         /* skip header */
422         sp = strstr(buf, "\n\n");
423
424         if (!sp || !size || type != OBJ_TAG) {
425                 free(buf);
426                 return;
427         }
428         sp += 2; /* skip the 2 LFs */
429         write_or_die(fd, sp, parse_signature(sp, buf + size - sp));
430
431         free(buf);
432 }
433
434 static int build_tag_object(struct strbuf *buf, int sign, unsigned char *result)
435 {
436         if (sign && do_sign(buf) < 0)
437                 return error(_("unable to sign the tag"));
438         if (write_sha1_file(buf->buf, buf->len, tag_type, result) < 0)
439                 return error(_("unable to write tag file"));
440         return 0;
441 }
442
443 struct create_tag_options {
444         unsigned int message_given:1;
445         unsigned int sign;
446         enum {
447                 CLEANUP_NONE,
448                 CLEANUP_SPACE,
449                 CLEANUP_ALL
450         } cleanup_mode;
451 };
452
453 static void create_tag(const unsigned char *object, const char *tag,
454                        struct strbuf *buf, struct create_tag_options *opt,
455                        unsigned char *prev, unsigned char *result)
456 {
457         enum object_type type;
458         char header_buf[1024];
459         int header_len;
460         char *path = NULL;
461
462         type = sha1_object_info(object, NULL);
463         if (type <= OBJ_NONE)
464             die(_("bad object type."));
465
466         header_len = snprintf(header_buf, sizeof(header_buf),
467                           "object %s\n"
468                           "type %s\n"
469                           "tag %s\n"
470                           "tagger %s\n\n",
471                           sha1_to_hex(object),
472                           typename(type),
473                           tag,
474                           git_committer_info(IDENT_STRICT));
475
476         if (header_len > sizeof(header_buf) - 1)
477                 die(_("tag header too big."));
478
479         if (!opt->message_given) {
480                 int fd;
481
482                 /* write the template message before editing: */
483                 path = git_pathdup("TAG_EDITMSG");
484                 fd = open(path, O_CREAT | O_TRUNC | O_WRONLY, 0600);
485                 if (fd < 0)
486                         die_errno(_("could not create file '%s'"), path);
487
488                 if (!is_null_sha1(prev)) {
489                         write_tag_body(fd, prev);
490                 } else {
491                         struct strbuf buf = STRBUF_INIT;
492                         strbuf_addch(&buf, '\n');
493                         if (opt->cleanup_mode == CLEANUP_ALL)
494                                 strbuf_commented_addf(&buf, _(tag_template), tag, comment_line_char);
495                         else
496                                 strbuf_commented_addf(&buf, _(tag_template_nocleanup), tag, comment_line_char);
497                         write_or_die(fd, buf.buf, buf.len);
498                         strbuf_release(&buf);
499                 }
500                 close(fd);
501
502                 if (launch_editor(path, buf, NULL)) {
503                         fprintf(stderr,
504                         _("Please supply the message using either -m or -F option.\n"));
505                         exit(1);
506                 }
507         }
508
509         if (opt->cleanup_mode != CLEANUP_NONE)
510                 stripspace(buf, opt->cleanup_mode == CLEANUP_ALL);
511
512         if (!opt->message_given && !buf->len)
513                 die(_("no tag message?"));
514
515         strbuf_insert(buf, 0, header_buf, header_len);
516
517         if (build_tag_object(buf, opt->sign, result) < 0) {
518                 if (path)
519                         fprintf(stderr, _("The tag message has been left in %s\n"),
520                                 path);
521                 exit(128);
522         }
523         if (path) {
524                 unlink_or_warn(path);
525                 free(path);
526         }
527 }
528
529 struct msg_arg {
530         int given;
531         struct strbuf buf;
532 };
533
534 static int parse_msg_arg(const struct option *opt, const char *arg, int unset)
535 {
536         struct msg_arg *msg = opt->value;
537
538         if (!arg)
539                 return -1;
540         if (msg->buf.len)
541                 strbuf_addstr(&(msg->buf), "\n\n");
542         strbuf_addstr(&(msg->buf), arg);
543         msg->given = 1;
544         return 0;
545 }
546
547 static int strbuf_check_tag_ref(struct strbuf *sb, const char *name)
548 {
549         if (name[0] == '-')
550                 return -1;
551
552         strbuf_reset(sb);
553         strbuf_addf(sb, "refs/tags/%s", name);
554
555         return check_refname_format(sb->buf, 0);
556 }
557
558 static int parse_opt_sort(const struct option *opt, const char *arg, int unset)
559 {
560         int *sort = opt->value;
561
562         return parse_sort_string(NULL, arg, sort);
563 }
564
565 int cmd_tag(int argc, const char **argv, const char *prefix)
566 {
567         struct strbuf buf = STRBUF_INIT;
568         struct strbuf ref = STRBUF_INIT;
569         unsigned char object[20], prev[20];
570         const char *object_ref, *tag;
571         struct create_tag_options opt;
572         char *cleanup_arg = NULL;
573         int annotate = 0, force = 0, lines = -1;
574         int cmdmode = 0;
575         const char *msgfile = NULL, *keyid = NULL;
576         struct msg_arg msg = { 0, STRBUF_INIT };
577         struct commit_list *with_commit = NULL;
578         struct ref_transaction *transaction;
579         struct strbuf err = STRBUF_INIT;
580         struct option options[] = {
581                 OPT_CMDMODE('l', "list", &cmdmode, N_("list tag names"), 'l'),
582                 { OPTION_INTEGER, 'n', NULL, &lines, N_("n"),
583                                 N_("print <n> lines of each tag message"),
584                                 PARSE_OPT_OPTARG, NULL, 1 },
585                 OPT_CMDMODE('d', "delete", &cmdmode, N_("delete tags"), 'd'),
586                 OPT_CMDMODE('v', "verify", &cmdmode, N_("verify tags"), 'v'),
587
588                 OPT_GROUP(N_("Tag creation options")),
589                 OPT_BOOL('a', "annotate", &annotate,
590                                         N_("annotated tag, needs a message")),
591                 OPT_CALLBACK('m', "message", &msg, N_("message"),
592                              N_("tag message"), parse_msg_arg),
593                 OPT_FILENAME('F', "file", &msgfile, N_("read message from file")),
594                 OPT_BOOL('s', "sign", &opt.sign, N_("annotated and GPG-signed tag")),
595                 OPT_STRING(0, "cleanup", &cleanup_arg, N_("mode"),
596                         N_("how to strip spaces and #comments from message")),
597                 OPT_STRING('u', "local-user", &keyid, N_("key-id"),
598                                         N_("use another key to sign the tag")),
599                 OPT__FORCE(&force, N_("replace the tag if exists")),
600
601                 OPT_GROUP(N_("Tag listing options")),
602                 OPT_COLUMN(0, "column", &colopts, N_("show tag list in columns")),
603                 OPT_CONTAINS(&with_commit, N_("print only tags that contain the commit")),
604                 OPT_WITH(&with_commit, N_("print only tags that contain the commit")),
605                 {
606                         OPTION_CALLBACK, 0, "sort", &tag_sort, N_("type"), N_("sort tags"),
607                         PARSE_OPT_NONEG, parse_opt_sort
608                 },
609                 {
610                         OPTION_CALLBACK, 0, "points-at", &points_at, N_("object"),
611                         N_("print only tags of the object"), 0, parse_opt_object_name
612                 },
613                 OPT_END()
614         };
615
616         git_config(git_tag_config, NULL);
617
618         memset(&opt, 0, sizeof(opt));
619
620         argc = parse_options(argc, argv, prefix, options, git_tag_usage, 0);
621
622         if (keyid) {
623                 opt.sign = 1;
624                 set_signing_key(keyid);
625         }
626         if (opt.sign)
627                 annotate = 1;
628         if (argc == 0 && !cmdmode)
629                 cmdmode = 'l';
630
631         if ((annotate || msg.given || msgfile || force) && (cmdmode != 0))
632                 usage_with_options(git_tag_usage, options);
633
634         finalize_colopts(&colopts, -1);
635         if (cmdmode == 'l' && lines != -1) {
636                 if (explicitly_enable_column(colopts))
637                         die(_("--column and -n are incompatible"));
638                 colopts = 0;
639         }
640         if (cmdmode == 'l') {
641                 int ret;
642                 if (column_active(colopts)) {
643                         struct column_options copts;
644                         memset(&copts, 0, sizeof(copts));
645                         copts.padding = 2;
646                         run_column_filter(colopts, &copts);
647                 }
648                 if (lines != -1 && tag_sort)
649                         die(_("--sort and -n are incompatible"));
650                 ret = list_tags(argv, lines == -1 ? 0 : lines, with_commit, tag_sort);
651                 if (column_active(colopts))
652                         stop_column_filter();
653                 return ret;
654         }
655         if (lines != -1)
656                 die(_("-n option is only allowed with -l."));
657         if (with_commit)
658                 die(_("--contains option is only allowed with -l."));
659         if (points_at.nr)
660                 die(_("--points-at option is only allowed with -l."));
661         if (cmdmode == 'd')
662                 return for_each_tag_name(argv, delete_tag);
663         if (cmdmode == 'v')
664                 return for_each_tag_name(argv, verify_tag);
665
666         if (msg.given || msgfile) {
667                 if (msg.given && msgfile)
668                         die(_("only one -F or -m option is allowed."));
669                 annotate = 1;
670                 if (msg.given)
671                         strbuf_addbuf(&buf, &(msg.buf));
672                 else {
673                         if (!strcmp(msgfile, "-")) {
674                                 if (strbuf_read(&buf, 0, 1024) < 0)
675                                         die_errno(_("cannot read '%s'"), msgfile);
676                         } else {
677                                 if (strbuf_read_file(&buf, msgfile, 1024) < 0)
678                                         die_errno(_("could not open or read '%s'"),
679                                                 msgfile);
680                         }
681                 }
682         }
683
684         tag = argv[0];
685
686         object_ref = argc == 2 ? argv[1] : "HEAD";
687         if (argc > 2)
688                 die(_("too many params"));
689
690         if (get_sha1(object_ref, object))
691                 die(_("Failed to resolve '%s' as a valid ref."), object_ref);
692
693         if (strbuf_check_tag_ref(&ref, tag))
694                 die(_("'%s' is not a valid tag name."), tag);
695
696         if (read_ref(ref.buf, prev))
697                 hashclr(prev);
698         else if (!force)
699                 die(_("tag '%s' already exists"), tag);
700
701         opt.message_given = msg.given || msgfile;
702
703         if (!cleanup_arg || !strcmp(cleanup_arg, "strip"))
704                 opt.cleanup_mode = CLEANUP_ALL;
705         else if (!strcmp(cleanup_arg, "verbatim"))
706                 opt.cleanup_mode = CLEANUP_NONE;
707         else if (!strcmp(cleanup_arg, "whitespace"))
708                 opt.cleanup_mode = CLEANUP_SPACE;
709         else
710                 die(_("Invalid cleanup mode %s"), cleanup_arg);
711
712         if (annotate)
713                 create_tag(object, tag, &buf, &opt, prev, object);
714
715         transaction = ref_transaction_begin(&err);
716         if (!transaction ||
717             ref_transaction_update(transaction, ref.buf, object, prev,
718                                    0, NULL, &err) ||
719             ref_transaction_commit(transaction, &err))
720                 die("%s", err.buf);
721         ref_transaction_free(transaction);
722         if (force && !is_null_sha1(prev) && hashcmp(prev, object))
723                 printf(_("Updated tag '%s' (was %s)\n"), tag, find_unique_abbrev(prev, DEFAULT_ABBREV));
724
725         strbuf_release(&err);
726         strbuf_release(&buf);
727         strbuf_release(&ref);
728         return 0;
729 }