git.oblomov.eu Git - git/blob - 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 "config.h"
  11 #include "builtin.h"
  12 #include "refs.h"
  13 #include "object-store.h"
  14 #include "tag.h"
  15 #include "run-command.h"
  16 #include "parse-options.h"
  17 #include "diff.h"
  18 #include "revision.h"
  19 #include "gpg-interface.h"
  20 #include "oid-array.h"
  21 #include "column.h"
  22 #include "ref-filter.h"
  23
  24 static const char * const git_tag_usage[] = {
  25         N_("git tag [-a | -s | -u <key-id>] [-f] [-m <msg> | -F <file>]\n"
  26                 "\t\t<tagname> [<head>]"),
  27         N_("git tag -d <tagname>..."),
  28         N_("git tag -l [-n[<num>]] [--contains <commit>] [--no-contains <commit>] [--points-at <object>]\n"
  29                 "\t\t[--format=<format>] [--merged <commit>] [--no-merged <commit>] [<pattern>...]"),
  30         N_("git tag -v [--format=<format>] <tagname>..."),
  31         NULL
  32 };
  33
  34 static unsigned int colopts;
  35 static int force_sign_annotate;
  36 static int config_sign_tag = -1; /* unspecified */
  37
  38 static int list_tags(struct ref_filter *filter, struct ref_sorting *sorting,
  39                      struct ref_format *format)
  40 {
  41         struct ref_array array;
  42         char *to_free = NULL;
  43         int i;
  44
  45         memset(&array, 0, sizeof(array));
  46
  47         if (filter->lines == -1)
  48                 filter->lines = 0;
  49
  50         if (!format->format) {
  51                 if (filter->lines) {
  52                         to_free = xstrfmt("%s %%(contents:lines=%d)",
  53                                           "%(align:15)%(refname:lstrip=2)%(end)",
  54                                           filter->lines);
  55                         format->format = to_free;
  56                 } else
  57                         format->format = "%(refname:lstrip=2)";
  58         }
  59
  60         if (verify_ref_format(format))
  61                 die(_("unable to parse format string"));
  62         filter->with_commit_tag_algo = 1;
  63         filter_refs(&array, filter, FILTER_REFS_TAGS);
  64         ref_array_sort(sorting, &array);
  65
  66         for (i = 0; i < array.nr; i++) {
  67                 struct strbuf output = STRBUF_INIT;
  68                 struct strbuf err = STRBUF_INIT;
  69
  70                 if (format_ref_array_item(array.items[i], format, &output, &err))
  71                         die("%s", err.buf);
  72                 fwrite(output.buf, 1, output.len, stdout);
  73                 putchar('\n');
  74
  75                 strbuf_release(&err);
  76                 strbuf_release(&output);
  77         }
  78         ref_array_clear(&array);
  79         free(to_free);
  80
  81         return 0;
  82 }
  83
  84 typedef int (*each_tag_name_fn)(const char *name, const char *ref,
  85                                 const struct object_id *oid, void *cb_data);
  86
  87 static int for_each_tag_name(const char **argv, each_tag_name_fn fn,
  88                              void *cb_data)
  89 {
  90         const char **p;
  91         struct strbuf ref = STRBUF_INIT;
  92         int had_error = 0;
  93         struct object_id oid;
  94
  95         for (p = argv; *p; p++) {
  96                 strbuf_reset(&ref);
  97                 strbuf_addf(&ref, "refs/tags/%s", *p);
  98                 if (read_ref(ref.buf, &oid)) {
  99                         error(_("tag '%s' not found."), *p);
 100                         had_error = 1;
 101                         continue;
 102                 }
 103                 if (fn(*p, ref.buf, &oid, cb_data))
 104                         had_error = 1;
 105         }
 106         strbuf_release(&ref);
 107         return had_error;
 108 }
 109
 110 static int collect_tags(const char *name, const char *ref,
 111                         const struct object_id *oid, void *cb_data)
 112 {
 113         struct string_list *ref_list = cb_data;
 114
 115         string_list_append(ref_list, ref);
 116         ref_list->items[ref_list->nr - 1].util = oiddup(oid);
 117         return 0;
 118 }
 119
 120 static int delete_tags(const char **argv)
 121 {
 122         int result;
 123         struct string_list refs_to_delete = STRING_LIST_INIT_DUP;
 124         struct string_list_item *item;
 125
 126         result = for_each_tag_name(argv, collect_tags, (void *)&refs_to_delete);
 127         if (delete_refs(NULL, &refs_to_delete, REF_NO_DEREF))
 128                 result = 1;
 129
 130         for_each_string_list_item(item, &refs_to_delete) {
 131                 const char *name = item->string;
 132                 struct object_id *oid = item->util;
 133                 if (!ref_exists(name))
 134                         printf(_("Deleted tag '%s' (was %s)\n"),
 135                                 item->string + 10,
 136                                 find_unique_abbrev(oid, DEFAULT_ABBREV));
 137
 138                 free(oid);
 139         }
 140         string_list_clear(&refs_to_delete, 0);
 141         return result;
 142 }
 143
 144 static int verify_tag(const char *name, const char *ref,
 145                       const struct object_id *oid, void *cb_data)
 146 {
 147         int flags;
 148         const struct ref_format *format = cb_data;
 149         flags = GPG_VERIFY_VERBOSE;
 150
 151         if (format->format)
 152                 flags = GPG_VERIFY_OMIT_STATUS;
 153
 154         if (gpg_verify_tag(oid, name, flags))
 155                 return -1;
 156
 157         if (format->format)
 158                 pretty_print_ref(name, oid, format);
 159
 160         return 0;
 161 }
 162
 163 static int do_sign(struct strbuf *buffer)
 164 {
 165         return sign_buffer(buffer, buffer, get_signing_key());
 166 }
 167
 168 static const char tag_template[] =
 169         N_("\nWrite a message for tag:\n  %s\n"
 170         "Lines starting with '%c' will be ignored.\n");
 171
 172 static const char tag_template_nocleanup[] =
 173         N_("\nWrite a message for tag:\n  %s\n"
 174         "Lines starting with '%c' will be kept; you may remove them"
 175         " yourself if you want to.\n");
 176
 177 static int git_tag_config(const char *var, const char *value, void *cb)
 178 {
 179         int status;
 180         struct ref_sorting **sorting_tail = (struct ref_sorting **)cb;
 181
 182         if (!strcmp(var, "tag.gpgsign")) {
 183                 config_sign_tag = git_config_bool(var, value);
 184                 return 0;
 185         }
 186
 187         if (!strcmp(var, "tag.sort")) {
 188                 if (!value)
 189                         return config_error_nonbool(var);
 190                 parse_ref_sorting(sorting_tail, value);
 191                 return 0;
 192         }
 193
 194         status = git_gpg_config(var, value, cb);
 195         if (status)
 196                 return status;
 197         if (!strcmp(var, "tag.forcesignannotated")) {
 198                 force_sign_annotate = git_config_bool(var, value);
 199                 return 0;
 200         }
 201
 202         if (starts_with(var, "column."))
 203                 return git_column_config(var, value, "tag", &colopts);
 204         return git_color_default_config(var, value, cb);
 205 }
 206
 207 static void write_tag_body(int fd, const struct object_id *oid)
 208 {
 209         unsigned long size;
 210         enum object_type type;
 211         char *buf, *sp, *orig;
 212         struct strbuf payload = STRBUF_INIT;
 213         struct strbuf signature = STRBUF_INIT;
 214
 215         orig = buf = read_object_file(oid, &type, &size);
 216         if (!buf)
 217                 return;
 218         if (parse_signature(buf, size, &payload, &signature)) {
 219                 buf = payload.buf;
 220                 size = payload.len;
 221         }
 222         /* skip header */
 223         sp = strstr(buf, "\n\n");
 224
 225         if (!sp || !size || type != OBJ_TAG) {
 226                 free(buf);
 227                 return;
 228         }
 229         sp += 2; /* skip the 2 LFs */
 230         write_or_die(fd, sp, buf + size - sp);
 231
 232         free(orig);
 233         strbuf_release(&payload);
 234         strbuf_release(&signature);
 235 }
 236
 237 static int build_tag_object(struct strbuf *buf, int sign, struct object_id *result)
 238 {
 239         if (sign && do_sign(buf) < 0)
 240                 return error(_("unable to sign the tag"));
 241         if (write_object_file(buf->buf, buf->len, tag_type, result) < 0)
 242                 return error(_("unable to write tag file"));
 243         return 0;
 244 }
 245
 246 struct create_tag_options {
 247         unsigned int message_given:1;
 248         unsigned int use_editor:1;
 249         unsigned int sign;
 250         enum {
 251                 CLEANUP_NONE,
 252                 CLEANUP_SPACE,
 253                 CLEANUP_ALL
 254         } cleanup_mode;
 255 };
 256
 257 static const char message_advice_nested_tag[] =
 258         N_("You have created a nested tag. The object referred to by your new tag is\n"
 259            "already a tag. If you meant to tag the object that it points to, use:\n"
 260            "\n"
 261            "\tgit tag -f %s %s^{}");
 262
 263 static void create_tag(const struct object_id *object, const char *object_ref,
 264                        const char *tag,
 265                        struct strbuf *buf, struct create_tag_options *opt,
 266                        struct object_id *prev, struct object_id *result)
 267 {
 268         enum object_type type;
 269         struct strbuf header = STRBUF_INIT;
 270         char *path = NULL;
 271
 272         type = oid_object_info(the_repository, object, NULL);
 273         if (type <= OBJ_NONE)
 274                 die(_("bad object type."));
 275
 276         if (type == OBJ_TAG)
 277                 advise_if_enabled(ADVICE_NESTED_TAG, _(message_advice_nested_tag),
 278                                   tag, object_ref);
 279
 280         strbuf_addf(&header,
 281                     "object %s\n"
 282                     "type %s\n"
 283                     "tag %s\n"
 284                     "tagger %s\n\n",
 285                     oid_to_hex(object),
 286                     type_name(type),
 287                     tag,
 288                     git_committer_info(IDENT_STRICT));
 289
 290         if (!opt->message_given || opt->use_editor) {
 291                 int fd;
 292
 293                 /* write the template message before editing: */
 294                 path = git_pathdup("TAG_EDITMSG");
 295                 fd = open(path, O_CREAT | O_TRUNC | O_WRONLY, 0600);
 296                 if (fd < 0)
 297                         die_errno(_("could not create file '%s'"), path);
 298
 299                 if (opt->message_given) {
 300                         write_or_die(fd, buf->buf, buf->len);
 301                         strbuf_reset(buf);
 302                 } else if (!is_null_oid(prev)) {
 303                         write_tag_body(fd, prev);
 304                 } else {
 305                         struct strbuf buf = STRBUF_INIT;
 306                         strbuf_addch(&buf, '\n');
 307                         if (opt->cleanup_mode == CLEANUP_ALL)
 308                                 strbuf_commented_addf(&buf, _(tag_template), tag, comment_line_char);
 309                         else
 310                                 strbuf_commented_addf(&buf, _(tag_template_nocleanup), tag, comment_line_char);
 311                         write_or_die(fd, buf.buf, buf.len);
 312                         strbuf_release(&buf);
 313                 }
 314                 close(fd);
 315
 316                 if (launch_editor(path, buf, NULL)) {
 317                         fprintf(stderr,
 318                         _("Please supply the message using either -m or -F option.\n"));
 319                         exit(1);
 320                 }
 321         }
 322
 323         if (opt->cleanup_mode != CLEANUP_NONE)
 324                 strbuf_stripspace(buf, opt->cleanup_mode == CLEANUP_ALL);
 325
 326         if (!opt->message_given && !buf->len)
 327                 die(_("no tag message?"));
 328
 329         strbuf_insert(buf, 0, header.buf, header.len);
 330         strbuf_release(&header);
 331
 332         if (build_tag_object(buf, opt->sign, result) < 0) {
 333                 if (path)
 334                         fprintf(stderr, _("The tag message has been left in %s\n"),
 335                                 path);
 336                 exit(128);
 337         }
 338         if (path) {
 339                 unlink_or_warn(path);
 340                 free(path);
 341         }
 342 }
 343
 344 static void create_reflog_msg(const struct object_id *oid, struct strbuf *sb)
 345 {
 346         enum object_type type;
 347         struct commit *c;
 348         char *buf;
 349         unsigned long size;
 350         int subject_len = 0;
 351         const char *subject_start;
 352
 353         char *rla = getenv("GIT_REFLOG_ACTION");
 354         if (rla) {
 355                 strbuf_addstr(sb, rla);
 356         } else {
 357                 strbuf_addstr(sb, "tag: tagging ");
 358                 strbuf_add_unique_abbrev(sb, oid, DEFAULT_ABBREV);
 359         }
 360
 361         strbuf_addstr(sb, " (");
 362         type = oid_object_info(the_repository, oid, NULL);
 363         switch (type) {
 364         default:
 365                 strbuf_addstr(sb, "object of unknown type");
 366                 break;
 367         case OBJ_COMMIT:
 368                 if ((buf = read_object_file(oid, &type, &size)) != NULL) {
 369                         subject_len = find_commit_subject(buf, &subject_start);
 370                         strbuf_insert(sb, sb->len, subject_start, subject_len);
 371                 } else {
 372                         strbuf_addstr(sb, "commit object");
 373                 }
 374                 free(buf);
 375
 376                 if ((c = lookup_commit_reference(the_repository, oid)) != NULL)
 377                         strbuf_addf(sb, ", %s", show_date(c->date, 0, DATE_MODE(SHORT)));
 378                 break;
 379         case OBJ_TREE:
 380                 strbuf_addstr(sb, "tree object");
 381                 break;
 382         case OBJ_BLOB:
 383                 strbuf_addstr(sb, "blob object");
 384                 break;
 385         case OBJ_TAG:
 386                 strbuf_addstr(sb, "other tag object");
 387                 break;
 388         }
 389         strbuf_addch(sb, ')');
 390 }
 391
 392 struct msg_arg {
 393         int given;
 394         struct strbuf buf;
 395 };
 396
 397 static int parse_msg_arg(const struct option *opt, const char *arg, int unset)
 398 {
 399         struct msg_arg *msg = opt->value;
 400
 401         BUG_ON_OPT_NEG(unset);
 402
 403         if (!arg)
 404                 return -1;
 405         if (msg->buf.len)
 406                 strbuf_addstr(&(msg->buf), "\n\n");
 407         strbuf_addstr(&(msg->buf), arg);
 408         msg->given = 1;
 409         return 0;
 410 }
 411
 412 static int strbuf_check_tag_ref(struct strbuf *sb, const char *name)
 413 {
 414         if (name[0] == '-')
 415                 return -1;
 416
 417         strbuf_reset(sb);
 418         strbuf_addf(sb, "refs/tags/%s", name);
 419
 420         return check_refname_format(sb->buf, 0);
 421 }
 422
 423 int cmd_tag(int argc, const char **argv, const char *prefix)
 424 {
 425         struct strbuf buf = STRBUF_INIT;
 426         struct strbuf ref = STRBUF_INIT;
 427         struct strbuf reflog_msg = STRBUF_INIT;
 428         struct object_id object, prev;
 429         const char *object_ref, *tag;
 430         struct create_tag_options opt;
 431         char *cleanup_arg = NULL;
 432         int create_reflog = 0;
 433         int annotate = 0, force = 0;
 434         int cmdmode = 0, create_tag_object = 0;
 435         const char *msgfile = NULL, *keyid = NULL;
 436         struct msg_arg msg = { 0, STRBUF_INIT };
 437         struct ref_transaction *transaction;
 438         struct strbuf err = STRBUF_INIT;
 439         struct ref_filter filter;
 440         static struct ref_sorting *sorting = NULL, **sorting_tail = &sorting;
 441         struct ref_format format = REF_FORMAT_INIT;
 442         int icase = 0;
 443         int edit_flag = 0;
 444         struct option options[] = {
 445                 OPT_CMDMODE('l', "list", &cmdmode, N_("list tag names"), 'l'),
 446                 { OPTION_INTEGER, 'n', NULL, &filter.lines, N_("n"),
 447                                 N_("print <n> lines of each tag message"),
 448                                 PARSE_OPT_OPTARG, NULL, 1 },
 449                 OPT_CMDMODE('d', "delete", &cmdmode, N_("delete tags"), 'd'),
 450                 OPT_CMDMODE('v', "verify", &cmdmode, N_("verify tags"), 'v'),
 451
 452                 OPT_GROUP(N_("Tag creation options")),
 453                 OPT_BOOL('a', "annotate", &annotate,
 454                                         N_("annotated tag, needs a message")),
 455                 OPT_CALLBACK_F('m', "message", &msg, N_("message"),
 456                                N_("tag message"), PARSE_OPT_NONEG, parse_msg_arg),
 457                 OPT_FILENAME('F', "file", &msgfile, N_("read message from file")),
 458                 OPT_BOOL('e', "edit", &edit_flag, N_("force edit of tag message")),
 459                 OPT_BOOL('s', "sign", &opt.sign, N_("annotated and GPG-signed tag")),
 460                 OPT_CLEANUP(&cleanup_arg),
 461                 OPT_STRING('u', "local-user", &keyid, N_("key-id"),
 462                                         N_("use another key to sign the tag")),
 463                 OPT__FORCE(&force, N_("replace the tag if exists"), 0),
 464                 OPT_BOOL(0, "create-reflog", &create_reflog, N_("create a reflog")),
 465
 466                 OPT_GROUP(N_("Tag listing options")),
 467                 OPT_COLUMN(0, "column", &colopts, N_("show tag list in columns")),
 468                 OPT_CONTAINS(&filter.with_commit, N_("print only tags that contain the commit")),
 469                 OPT_NO_CONTAINS(&filter.no_commit, N_("print only tags that don't contain the commit")),
 470                 OPT_WITH(&filter.with_commit, N_("print only tags that contain the commit")),
 471                 OPT_WITHOUT(&filter.no_commit, N_("print only tags that don't contain the commit")),
 472                 OPT_MERGED(&filter, N_("print only tags that are merged")),
 473                 OPT_NO_MERGED(&filter, N_("print only tags that are not merged")),
 474                 OPT_REF_SORT(sorting_tail),
 475                 {
 476                         OPTION_CALLBACK, 0, "points-at", &filter.points_at, N_("object"),
 477                         N_("print only tags of the object"), PARSE_OPT_LASTARG_DEFAULT,
 478                         parse_opt_object_name, (intptr_t) "HEAD"
 479                 },
 480                 OPT_STRING(  0 , "format", &format.format, N_("format"),
 481                            N_("format to use for the output")),
 482                 OPT__COLOR(&format.use_color, N_("respect format colors")),
 483                 OPT_BOOL('i', "ignore-case", &icase, N_("sorting and filtering are case insensitive")),
 484                 OPT_END()
 485         };
 486
 487         setup_ref_filter_porcelain_msg();
 488
 489         git_config(git_tag_config, sorting_tail);
 490
 491         memset(&opt, 0, sizeof(opt));
 492         memset(&filter, 0, sizeof(filter));
 493         filter.lines = -1;
 494         opt.sign = -1;
 495
 496         argc = parse_options(argc, argv, prefix, options, git_tag_usage, 0);
 497
 498         if (!cmdmode) {
 499                 if (argc == 0)
 500                         cmdmode = 'l';
 501                 else if (filter.with_commit || filter.no_commit ||
 502                          filter.reachable_from || filter.unreachable_from ||
 503                          filter.points_at.nr || filter.lines != -1)
 504                         cmdmode = 'l';
 505         }
 506
 507         if (cmdmode == 'l')
 508                 setup_auto_pager("tag", 1);
 509
 510         if (opt.sign == -1)
 511                 opt.sign = cmdmode ? 0 : config_sign_tag > 0;
 512
 513         if (keyid) {
 514                 opt.sign = 1;
 515                 set_signing_key(keyid);
 516         }
 517         create_tag_object = (opt.sign || annotate || msg.given || msgfile);
 518
 519         if ((create_tag_object || force) && (cmdmode != 0))
 520                 usage_with_options(git_tag_usage, options);
 521
 522         finalize_colopts(&colopts, -1);
 523         if (cmdmode == 'l' && filter.lines != -1) {
 524                 if (explicitly_enable_column(colopts))
 525                         die(_("--column and -n are incompatible"));
 526                 colopts = 0;
 527         }
 528         if (!sorting)
 529                 sorting = ref_default_sorting();
 530         ref_sorting_set_sort_flags_all(sorting, REF_SORTING_ICASE, icase);
 531         filter.ignore_case = icase;
 532         if (cmdmode == 'l') {
 533                 int ret;
 534                 if (column_active(colopts)) {
 535                         struct column_options copts;
 536                         memset(&copts, 0, sizeof(copts));
 537                         copts.padding = 2;
 538                         run_column_filter(colopts, &copts);
 539                 }
 540                 filter.name_patterns = argv;
 541                 ret = list_tags(&filter, sorting, &format);
 542                 if (column_active(colopts))
 543                         stop_column_filter();
 544                 return ret;
 545         }
 546         if (filter.lines != -1)
 547                 die(_("-n option is only allowed in list mode"));
 548         if (filter.with_commit)
 549                 die(_("--contains option is only allowed in list mode"));
 550         if (filter.no_commit)
 551                 die(_("--no-contains option is only allowed in list mode"));
 552         if (filter.points_at.nr)
 553                 die(_("--points-at option is only allowed in list mode"));
 554         if (filter.reachable_from || filter.unreachable_from)
 555                 die(_("--merged and --no-merged options are only allowed in list mode"));
 556         if (cmdmode == 'd')
 557                 return delete_tags(argv);
 558         if (cmdmode == 'v') {
 559                 if (format.format && verify_ref_format(&format))
 560                         usage_with_options(git_tag_usage, options);
 561                 return for_each_tag_name(argv, verify_tag, &format);
 562         }
 563
 564         if (msg.given || msgfile) {
 565                 if (msg.given && msgfile)
 566                         die(_("only one -F or -m option is allowed."));
 567                 if (msg.given)
 568                         strbuf_addbuf(&buf, &(msg.buf));
 569                 else {
 570                         if (!strcmp(msgfile, "-")) {
 571                                 if (strbuf_read(&buf, 0, 1024) < 0)
 572                                         die_errno(_("cannot read '%s'"), msgfile);
 573                         } else {
 574                                 if (strbuf_read_file(&buf, msgfile, 1024) < 0)
 575                                         die_errno(_("could not open or read '%s'"),
 576                                                 msgfile);
 577                         }
 578                 }
 579         }
 580
 581         tag = argv[0];
 582
 583         object_ref = argc == 2 ? argv[1] : "HEAD";
 584         if (argc > 2)
 585                 die(_("too many arguments"));
 586
 587         if (get_oid(object_ref, &object))
 588                 die(_("Failed to resolve '%s' as a valid ref."), object_ref);
 589
 590         if (strbuf_check_tag_ref(&ref, tag))
 591                 die(_("'%s' is not a valid tag name."), tag);
 592
 593         if (read_ref(ref.buf, &prev))
 594                 oidclr(&prev);
 595         else if (!force)
 596                 die(_("tag '%s' already exists"), tag);
 597
 598         opt.message_given = msg.given || msgfile;
 599         opt.use_editor = edit_flag;
 600
 601         if (!cleanup_arg || !strcmp(cleanup_arg, "strip"))
 602                 opt.cleanup_mode = CLEANUP_ALL;
 603         else if (!strcmp(cleanup_arg, "verbatim"))
 604                 opt.cleanup_mode = CLEANUP_NONE;
 605         else if (!strcmp(cleanup_arg, "whitespace"))
 606                 opt.cleanup_mode = CLEANUP_SPACE;
 607         else
 608                 die(_("Invalid cleanup mode %s"), cleanup_arg);
 609
 610         create_reflog_msg(&object, &reflog_msg);
 611
 612         if (create_tag_object) {
 613                 if (force_sign_annotate && !annotate)
 614                         opt.sign = 1;
 615                 create_tag(&object, object_ref, tag, &buf, &opt, &prev, &object);
 616         }
 617
 618         transaction = ref_transaction_begin(&err);
 619         if (!transaction ||
 620             ref_transaction_update(transaction, ref.buf, &object, &prev,
 621                                    create_reflog ? REF_FORCE_CREATE_REFLOG : 0,
 622                                    reflog_msg.buf, &err) ||
 623             ref_transaction_commit(transaction, &err))
 624                 die("%s", err.buf);
 625         ref_transaction_free(transaction);
 626         if (force && !is_null_oid(&prev) && !oideq(&prev, &object))
 627                 printf(_("Updated tag '%s' (was %s)\n"), tag,
 628                        find_unique_abbrev(&prev, DEFAULT_ABBREV));
 629
 630         UNLEAK(buf);
 631         UNLEAK(ref);
 632         UNLEAK(reflog_msg);
 633         UNLEAK(msg);
 634         UNLEAK(err);
 635         return 0;
 636 }