Andrew's git / gitweb.git / builtin/fmt-merge-msg.c
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builtin / fmt-merge-msg.con commit Merge branch 'ta/user-manual' (8fbb07e)
   1#include "builtin.h"
   2#include "cache.h"
   3#include "commit.h"
   4#include "diff.h"
   5#include "revision.h"
   6#include "tag.h"
   7#include "string-list.h"
   8#include "branch.h"
   9#include "fmt-merge-msg.h"
  10#include "gpg-interface.h"
  11
  12static const char * const fmt_merge_msg_usage[] = {
  13        N_("git fmt-merge-msg [-m <message>] [--log[=<n>]|--no-log] [--file <file>]"),
  14        NULL
  15};
  16
  17static int use_branch_desc;
  18
  19int fmt_merge_msg_config(const char *key, const char *value, void *cb)
  20{
  21        if (!strcmp(key, "merge.log") || !strcmp(key, "merge.summary")) {
  22                int is_bool;
  23                merge_log_config = git_config_bool_or_int(key, value, &is_bool);
  24                if (!is_bool && merge_log_config < 0)
  25                        return error("%s: negative length %s", key, value);
  26                if (is_bool && merge_log_config)
  27                        merge_log_config = DEFAULT_MERGE_LOG_LEN;
  28        } else if (!strcmp(key, "merge.branchdesc")) {
  29                use_branch_desc = git_config_bool(key, value);
  30        } else {
  31                return git_default_config(key, value, cb);
  32        }
  33        return 0;
  34}
  35
  36/* merge data per repository where the merged tips came from */
  37struct src_data {
  38        struct string_list branch, tag, r_branch, generic;
  39        int head_status;
  40};
  41
  42struct origin_data {
  43        unsigned char sha1[20];
  44        unsigned is_local_branch:1;
  45};
  46
  47static void init_src_data(struct src_data *data)
  48{
  49        data->branch.strdup_strings = 1;
  50        data->tag.strdup_strings = 1;
  51        data->r_branch.strdup_strings = 1;
  52        data->generic.strdup_strings = 1;
  53}
  54
  55static struct string_list srcs = STRING_LIST_INIT_DUP;
  56static struct string_list origins = STRING_LIST_INIT_DUP;
  57
  58struct merge_parents {
  59        int alloc, nr;
  60        struct merge_parent {
  61                unsigned char given[20];
  62                unsigned char commit[20];
  63                unsigned char used;
  64        } *item;
  65};
  66
  67/*
  68 * I know, I know, this is inefficient, but you won't be pulling and merging
  69 * hundreds of heads at a time anyway.
  70 */
  71static struct merge_parent *find_merge_parent(struct merge_parents *table,
  72                                              unsigned char *given,
  73                                              unsigned char *commit)
  74{
  75        int i;
  76        for (i = 0; i < table->nr; i++) {
  77                if (given && hashcmp(table->item[i].given, given))
  78                        continue;
  79                if (commit && hashcmp(table->item[i].commit, commit))
  80                        continue;
  81                return &table->item[i];
  82        }
  83        return NULL;
  84}
  85
  86static void add_merge_parent(struct merge_parents *table,
  87                             unsigned char *given,
  88                             unsigned char *commit)
  89{
  90        if (table->nr && find_merge_parent(table, given, commit))
  91                return;
  92        ALLOC_GROW(table->item, table->nr + 1, table->alloc);
  93        hashcpy(table->item[table->nr].given, given);
  94        hashcpy(table->item[table->nr].commit, commit);
  95        table->item[table->nr].used = 0;
  96        table->nr++;
  97}
  98
  99static int handle_line(char *line, struct merge_parents *merge_parents)
 100{
 101        int i, len = strlen(line);
 102        struct origin_data *origin_data;
 103        char *src, *origin;
 104        struct src_data *src_data;
 105        struct string_list_item *item;
 106        int pulling_head = 0;
 107        unsigned char sha1[20];
 108
 109        if (len < 43 || line[40] != '\t')
 110                return 1;
 111
 112        if (!prefixcmp(line + 41, "not-for-merge"))
 113                return 0;
 114
 115        if (line[41] != '\t')
 116                return 2;
 117
 118        i = get_sha1_hex(line, sha1);
 119        if (i)
 120                return 3;
 121
 122        if (!find_merge_parent(merge_parents, sha1, NULL))
 123                return 0; /* subsumed by other parents */
 124
 125        origin_data = xcalloc(1, sizeof(struct origin_data));
 126        hashcpy(origin_data->sha1, sha1);
 127
 128        if (line[len - 1] == '\n')
 129                line[len - 1] = 0;
 130        line += 42;
 131
 132        /*
 133         * At this point, line points at the beginning of comment e.g.
 134         * "branch 'frotz' of git://that/repository.git".
 135         * Find the repository name and point it with src.
 136         */
 137        src = strstr(line, " of ");
 138        if (src) {
 139                *src = 0;
 140                src += 4;
 141                pulling_head = 0;
 142        } else {
 143                src = line;
 144                pulling_head = 1;
 145        }
 146
 147        item = unsorted_string_list_lookup(&srcs, src);
 148        if (!item) {
 149                item = string_list_append(&srcs, src);
 150                item->util = xcalloc(1, sizeof(struct src_data));
 151                init_src_data(item->util);
 152        }
 153        src_data = item->util;
 154
 155        if (pulling_head) {
 156                origin = src;
 157                src_data->head_status |= 1;
 158        } else if (!prefixcmp(line, "branch ")) {
 159                origin_data->is_local_branch = 1;
 160                origin = line + 7;
 161                string_list_append(&src_data->branch, origin);
 162                src_data->head_status |= 2;
 163        } else if (!prefixcmp(line, "tag ")) {
 164                origin = line;
 165                string_list_append(&src_data->tag, origin + 4);
 166                src_data->head_status |= 2;
 167        } else if (!prefixcmp(line, "remote-tracking branch ")) {
 168                origin = line + strlen("remote-tracking branch ");
 169                string_list_append(&src_data->r_branch, origin);
 170                src_data->head_status |= 2;
 171        } else {
 172                origin = src;
 173                string_list_append(&src_data->generic, line);
 174                src_data->head_status |= 2;
 175        }
 176
 177        if (!strcmp(".", src) || !strcmp(src, origin)) {
 178                int len = strlen(origin);
 179                if (origin[0] == '\'' && origin[len - 1] == '\'')
 180                        origin = xmemdupz(origin + 1, len - 2);
 181        } else {
 182                char *new_origin = xmalloc(strlen(origin) + strlen(src) + 5);
 183                sprintf(new_origin, "%s of %s", origin, src);
 184                origin = new_origin;
 185        }
 186        if (strcmp(".", src))
 187                origin_data->is_local_branch = 0;
 188        string_list_append(&origins, origin)->util = origin_data;
 189        return 0;
 190}
 191
 192static void print_joined(const char *singular, const char *plural,
 193                struct string_list *list, struct strbuf *out)
 194{
 195        if (list->nr == 0)
 196                return;
 197        if (list->nr == 1) {
 198                strbuf_addf(out, "%s%s", singular, list->items[0].string);
 199        } else {
 200                int i;
 201                strbuf_addstr(out, plural);
 202                for (i = 0; i < list->nr - 1; i++)
 203                        strbuf_addf(out, "%s%s", i > 0 ? ", " : "",
 204                                    list->items[i].string);
 205                strbuf_addf(out, " and %s", list->items[list->nr - 1].string);
 206        }
 207}
 208
 209static void add_branch_desc(struct strbuf *out, const char *name)
 210{
 211        struct strbuf desc = STRBUF_INIT;
 212
 213        if (!read_branch_desc(&desc, name)) {
 214                const char *bp = desc.buf;
 215                while (*bp) {
 216                        const char *ep = strchrnul(bp, '\n');
 217                        if (*ep)
 218                                ep++;
 219                        strbuf_addf(out, "  : %.*s", (int)(ep - bp), bp);
 220                        bp = ep;
 221                }
 222                if (out->buf[out->len - 1] != '\n')
 223                        strbuf_addch(out, '\n');
 224        }
 225        strbuf_release(&desc);
 226}
 227
 228#define util_as_integral(elem) ((intptr_t)((elem)->util))
 229
 230static void record_person(int which, struct string_list *people,
 231                          struct commit *commit)
 232{
 233        char *name_buf, *name, *name_end;
 234        struct string_list_item *elem;
 235        const char *field;
 236
 237        field = (which == 'a') ? "\nauthor " : "\ncommitter ";
 238        name = strstr(commit->buffer, field);
 239        if (!name)
 240                return;
 241        name += strlen(field);
 242        name_end = strchrnul(name, '<');
 243        if (*name_end)
 244                name_end--;
 245        while (isspace(*name_end) && name <= name_end)
 246                name_end--;
 247        if (name_end < name)
 248                return;
 249        name_buf = xmemdupz(name, name_end - name + 1);
 250
 251        elem = string_list_lookup(people, name_buf);
 252        if (!elem) {
 253                elem = string_list_insert(people, name_buf);
 254                elem->util = (void *)0;
 255        }
 256        elem->util = (void*)(util_as_integral(elem) + 1);
 257        free(name_buf);
 258}
 259
 260static int cmp_string_list_util_as_integral(const void *a_, const void *b_)
 261{
 262        const struct string_list_item *a = a_, *b = b_;
 263        return util_as_integral(b) - util_as_integral(a);
 264}
 265
 266static void add_people_count(struct strbuf *out, struct string_list *people)
 267{
 268        if (people->nr == 1)
 269                strbuf_addf(out, "%s", people->items[0].string);
 270        else if (people->nr == 2)
 271                strbuf_addf(out, "%s (%d) and %s (%d)",
 272                            people->items[0].string,
 273                            (int)util_as_integral(&people->items[0]),
 274                            people->items[1].string,
 275                            (int)util_as_integral(&people->items[1]));
 276        else if (people->nr)
 277                strbuf_addf(out, "%s (%d) and others",
 278                            people->items[0].string,
 279                            (int)util_as_integral(&people->items[0]));
 280}
 281
 282static void credit_people(struct strbuf *out,
 283                          struct string_list *them,
 284                          int kind)
 285{
 286        const char *label;
 287        const char *me;
 288
 289        if (kind == 'a') {
 290                label = "By";
 291                me = git_author_info(IDENT_NO_DATE);
 292        } else {
 293                label = "Via";
 294                me = git_committer_info(IDENT_NO_DATE);
 295        }
 296
 297        if (!them->nr ||
 298            (them->nr == 1 &&
 299             me &&
 300             (me = skip_prefix(me, them->items->string)) != NULL &&
 301             skip_prefix(me, " <")))
 302                return;
 303        strbuf_addf(out, "\n%c %s ", comment_line_char, label);
 304        add_people_count(out, them);
 305}
 306
 307static void add_people_info(struct strbuf *out,
 308                            struct string_list *authors,
 309                            struct string_list *committers)
 310{
 311        if (authors->nr)
 312                qsort(authors->items,
 313                      authors->nr, sizeof(authors->items[0]),
 314                      cmp_string_list_util_as_integral);
 315        if (committers->nr)
 316                qsort(committers->items,
 317                      committers->nr, sizeof(committers->items[0]),
 318                      cmp_string_list_util_as_integral);
 319
 320        credit_people(out, authors, 'a');
 321        credit_people(out, committers, 'c');
 322}
 323
 324static void shortlog(const char *name,
 325                     struct origin_data *origin_data,
 326                     struct commit *head,
 327                     struct rev_info *rev,
 328                     struct fmt_merge_msg_opts *opts,
 329                     struct strbuf *out)
 330{
 331        int i, count = 0;
 332        struct commit *commit;
 333        struct object *branch;
 334        struct string_list subjects = STRING_LIST_INIT_DUP;
 335        struct string_list authors = STRING_LIST_INIT_DUP;
 336        struct string_list committers = STRING_LIST_INIT_DUP;
 337        int flags = UNINTERESTING | TREESAME | SEEN | SHOWN | ADDED;
 338        struct strbuf sb = STRBUF_INIT;
 339        const unsigned char *sha1 = origin_data->sha1;
 340        int limit = opts->shortlog_len;
 341
 342        branch = deref_tag(parse_object(sha1), sha1_to_hex(sha1), 40);
 343        if (!branch || branch->type != OBJ_COMMIT)
 344                return;
 345
 346        setup_revisions(0, NULL, rev, NULL);
 347        add_pending_object(rev, branch, name);
 348        add_pending_object(rev, &head->object, "^HEAD");
 349        head->object.flags |= UNINTERESTING;
 350        if (prepare_revision_walk(rev))
 351                die("revision walk setup failed");
 352        while ((commit = get_revision(rev)) != NULL) {
 353                struct pretty_print_context ctx = {0};
 354
 355                if (commit->parents && commit->parents->next) {
 356                        /* do not list a merge but count committer */
 357                        if (opts->credit_people)
 358                                record_person('c', &committers, commit);
 359                        continue;
 360                }
 361                if (!count && opts->credit_people)
 362                        /* the 'tip' committer */
 363                        record_person('c', &committers, commit);
 364                if (opts->credit_people)
 365                        record_person('a', &authors, commit);
 366                count++;
 367                if (subjects.nr > limit)
 368                        continue;
 369
 370                format_commit_message(commit, "%s", &sb, &ctx);
 371                strbuf_ltrim(&sb);
 372
 373                if (!sb.len)
 374                        string_list_append(&subjects,
 375                                           sha1_to_hex(commit->object.sha1));
 376                else
 377                        string_list_append(&subjects, strbuf_detach(&sb, NULL));
 378        }
 379
 380        if (opts->credit_people)
 381                add_people_info(out, &authors, &committers);
 382        if (count > limit)
 383                strbuf_addf(out, "\n* %s: (%d commits)\n", name, count);
 384        else
 385                strbuf_addf(out, "\n* %s:\n", name);
 386
 387        if (origin_data->is_local_branch && use_branch_desc)
 388                add_branch_desc(out, name);
 389
 390        for (i = 0; i < subjects.nr; i++)
 391                if (i >= limit)
 392                        strbuf_addf(out, "  ...\n");
 393                else
 394                        strbuf_addf(out, "  %s\n", subjects.items[i].string);
 395
 396        clear_commit_marks((struct commit *)branch, flags);
 397        clear_commit_marks(head, flags);
 398        free_commit_list(rev->commits);
 399        rev->commits = NULL;
 400        rev->pending.nr = 0;
 401
 402        string_list_clear(&authors, 0);
 403        string_list_clear(&committers, 0);
 404        string_list_clear(&subjects, 0);
 405}
 406
 407static void fmt_merge_msg_title(struct strbuf *out,
 408        const char *current_branch) {
 409        int i = 0;
 410        char *sep = "";
 411
 412        strbuf_addstr(out, "Merge ");
 413        for (i = 0; i < srcs.nr; i++) {
 414                struct src_data *src_data = srcs.items[i].util;
 415                const char *subsep = "";
 416
 417                strbuf_addstr(out, sep);
 418                sep = "; ";
 419
 420                if (src_data->head_status == 1) {
 421                        strbuf_addstr(out, srcs.items[i].string);
 422                        continue;
 423                }
 424                if (src_data->head_status == 3) {
 425                        subsep = ", ";
 426                        strbuf_addstr(out, "HEAD");
 427                }
 428                if (src_data->branch.nr) {
 429                        strbuf_addstr(out, subsep);
 430                        subsep = ", ";
 431                        print_joined("branch ", "branches ", &src_data->branch,
 432                                        out);
 433                }
 434                if (src_data->r_branch.nr) {
 435                        strbuf_addstr(out, subsep);
 436                        subsep = ", ";
 437                        print_joined("remote-tracking branch ", "remote-tracking branches ",
 438                                        &src_data->r_branch, out);
 439                }
 440                if (src_data->tag.nr) {
 441                        strbuf_addstr(out, subsep);
 442                        subsep = ", ";
 443                        print_joined("tag ", "tags ", &src_data->tag, out);
 444                }
 445                if (src_data->generic.nr) {
 446                        strbuf_addstr(out, subsep);
 447                        print_joined("commit ", "commits ", &src_data->generic,
 448                                        out);
 449                }
 450                if (strcmp(".", srcs.items[i].string))
 451                        strbuf_addf(out, " of %s", srcs.items[i].string);
 452        }
 453
 454        if (!strcmp("master", current_branch))
 455                strbuf_addch(out, '\n');
 456        else
 457                strbuf_addf(out, " into %s\n", current_branch);
 458}
 459
 460static void fmt_tag_signature(struct strbuf *tagbuf,
 461                              struct strbuf *sig,
 462                              const char *buf,
 463                              unsigned long len)
 464{
 465        const char *tag_body = strstr(buf, "\n\n");
 466        if (tag_body) {
 467                tag_body += 2;
 468                strbuf_add(tagbuf, tag_body, buf + len - tag_body);
 469        }
 470        strbuf_complete_line(tagbuf);
 471        if (sig->len) {
 472                strbuf_addch(tagbuf, '\n');
 473                strbuf_add_commented_lines(tagbuf, sig->buf, sig->len);
 474        }
 475}
 476
 477static void fmt_merge_msg_sigs(struct strbuf *out)
 478{
 479        int i, tag_number = 0, first_tag = 0;
 480        struct strbuf tagbuf = STRBUF_INIT;
 481
 482        for (i = 0; i < origins.nr; i++) {
 483                unsigned char *sha1 = origins.items[i].util;
 484                enum object_type type;
 485                unsigned long size, len;
 486                char *buf = read_sha1_file(sha1, &type, &size);
 487                struct strbuf sig = STRBUF_INIT;
 488
 489                if (!buf || type != OBJ_TAG)
 490                        goto next;
 491                len = parse_signature(buf, size);
 492
 493                if (size == len)
 494                        ; /* merely annotated */
 495                else if (verify_signed_buffer(buf, len, buf + len, size - len, &sig, NULL)) {
 496                        if (!sig.len)
 497                                strbuf_addstr(&sig, "gpg verification failed.\n");
 498                }
 499
 500                if (!tag_number++) {
 501                        fmt_tag_signature(&tagbuf, &sig, buf, len);
 502                        first_tag = i;
 503                } else {
 504                        if (tag_number == 2) {
 505                                struct strbuf tagline = STRBUF_INIT;
 506                                strbuf_addch(&tagline, '\n');
 507                                strbuf_add_commented_lines(&tagline,
 508                                                origins.items[first_tag].string,
 509                                                strlen(origins.items[first_tag].string));
 510                                strbuf_insert(&tagbuf, 0, tagline.buf,
 511                                              tagline.len);
 512                                strbuf_release(&tagline);
 513                        }
 514                        strbuf_addch(&tagbuf, '\n');
 515                        strbuf_add_commented_lines(&tagbuf,
 516                                        origins.items[i].string,
 517                                        strlen(origins.items[i].string));
 518                        fmt_tag_signature(&tagbuf, &sig, buf, len);
 519                }
 520                strbuf_release(&sig);
 521        next:
 522                free(buf);
 523        }
 524        if (tagbuf.len) {
 525                strbuf_addch(out, '\n');
 526                strbuf_addbuf(out, &tagbuf);
 527        }
 528        strbuf_release(&tagbuf);
 529}
 530
 531static void find_merge_parents(struct merge_parents *result,
 532                               struct strbuf *in, unsigned char *head)
 533{
 534        struct commit_list *parents, *next;
 535        struct commit *head_commit;
 536        int pos = 0, i, j;
 537
 538        parents = NULL;
 539        while (pos < in->len) {
 540                int len;
 541                char *p = in->buf + pos;
 542                char *newline = strchr(p, '\n');
 543                unsigned char sha1[20];
 544                struct commit *parent;
 545                struct object *obj;
 546
 547                len = newline ? newline - p : strlen(p);
 548                pos += len + !!newline;
 549
 550                if (len < 43 ||
 551                    get_sha1_hex(p, sha1) ||
 552                    p[40] != '\t' ||
 553                    p[41] != '\t')
 554                        continue; /* skip not-for-merge */
 555                /*
 556                 * Do not use get_merge_parent() here; we do not have
 557                 * "name" here and we do not want to contaminate its
 558                 * util field yet.
 559                 */
 560                obj = parse_object(sha1);
 561                parent = (struct commit *)peel_to_type(NULL, 0, obj, OBJ_COMMIT);
 562                if (!parent)
 563                        continue;
 564                commit_list_insert(parent, &parents);
 565                add_merge_parent(result, obj->sha1, parent->object.sha1);
 566        }
 567        head_commit = lookup_commit(head);
 568        if (head_commit)
 569                commit_list_insert(head_commit, &parents);
 570        parents = reduce_heads(parents);
 571
 572        while (parents) {
 573                for (i = 0; i < result->nr; i++)
 574                        if (!hashcmp(result->item[i].commit,
 575                                     parents->item->object.sha1))
 576                                result->item[i].used = 1;
 577                next = parents->next;
 578                free(parents);
 579                parents = next;
 580        }
 581
 582        for (i = j = 0; i < result->nr; i++) {
 583                if (result->item[i].used) {
 584                        if (i != j)
 585                                result->item[j] = result->item[i];
 586                        j++;
 587                }
 588        }
 589        result->nr = j;
 590}
 591
 592int fmt_merge_msg(struct strbuf *in, struct strbuf *out,
 593                  struct fmt_merge_msg_opts *opts)
 594{
 595        int i = 0, pos = 0;
 596        unsigned char head_sha1[20];
 597        const char *current_branch;
 598        void *current_branch_to_free;
 599        struct merge_parents merge_parents;
 600
 601        memset(&merge_parents, 0, sizeof(merge_parents));
 602
 603        /* get current branch */
 604        current_branch = current_branch_to_free =
 605                resolve_refdup("HEAD", head_sha1, 1, NULL);
 606        if (!current_branch)
 607                die("No current branch");
 608        if (!prefixcmp(current_branch, "refs/heads/"))
 609                current_branch += 11;
 610
 611        find_merge_parents(&merge_parents, in, head_sha1);
 612
 613        /* get a line */
 614        while (pos < in->len) {
 615                int len;
 616                char *newline, *p = in->buf + pos;
 617
 618                newline = strchr(p, '\n');
 619                len = newline ? newline - p : strlen(p);
 620                pos += len + !!newline;
 621                i++;
 622                p[len] = 0;
 623                if (handle_line(p, &merge_parents))
 624                        die ("Error in line %d: %.*s", i, len, p);
 625        }
 626
 627        if (opts->add_title && srcs.nr)
 628                fmt_merge_msg_title(out, current_branch);
 629
 630        if (origins.nr)
 631                fmt_merge_msg_sigs(out);
 632
 633        if (opts->shortlog_len) {
 634                struct commit *head;
 635                struct rev_info rev;
 636
 637                head = lookup_commit_or_die(head_sha1, "HEAD");
 638                init_revisions(&rev, NULL);
 639                rev.commit_format = CMIT_FMT_ONELINE;
 640                rev.ignore_merges = 1;
 641                rev.limited = 1;
 642
 643                strbuf_complete_line(out);
 644
 645                for (i = 0; i < origins.nr; i++)
 646                        shortlog(origins.items[i].string,
 647                                 origins.items[i].util,
 648                                 head, &rev, opts, out);
 649        }
 650
 651        strbuf_complete_line(out);
 652        free(current_branch_to_free);
 653        free(merge_parents.item);
 654        return 0;
 655}
 656
 657int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
 658{
 659        const char *inpath = NULL;
 660        const char *message = NULL;
 661        int shortlog_len = -1;
 662        struct option options[] = {
 663                { OPTION_INTEGER, 0, "log", &shortlog_len, N_("n"),
 664                  N_("populate log with at most <n> entries from shortlog"),
 665                  PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
 666                { OPTION_INTEGER, 0, "summary", &shortlog_len, N_("n"),
 667                  N_("alias for --log (deprecated)"),
 668                  PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, NULL,
 669                  DEFAULT_MERGE_LOG_LEN },
 670                OPT_STRING('m', "message", &message, N_("text"),
 671                        N_("use <text> as start of message")),
 672                OPT_FILENAME('F', "file", &inpath, N_("file to read from")),
 673                OPT_END()
 674        };
 675
 676        FILE *in = stdin;
 677        struct strbuf input = STRBUF_INIT, output = STRBUF_INIT;
 678        int ret;
 679        struct fmt_merge_msg_opts opts;
 680
 681        git_config(fmt_merge_msg_config, NULL);
 682        argc = parse_options(argc, argv, prefix, options, fmt_merge_msg_usage,
 683                             0);
 684        if (argc > 0)
 685                usage_with_options(fmt_merge_msg_usage, options);
 686        if (shortlog_len < 0)
 687                shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;
 688
 689        if (inpath && strcmp(inpath, "-")) {
 690                in = fopen(inpath, "r");
 691                if (!in)
 692                        die_errno("cannot open '%s'", inpath);
 693        }
 694
 695        if (strbuf_read(&input, fileno(in), 0) < 0)
 696                die_errno("could not read input file");
 697
 698        if (message)
 699                strbuf_addstr(&output, message);
 700
 701        memset(&opts, 0, sizeof(opts));
 702        opts.add_title = !message;
 703        opts.credit_people = 1;
 704        opts.shortlog_len = shortlog_len;
 705
 706        ret = fmt_merge_msg(&input, &output, &opts);
 707        if (ret)
 708                return ret;
 709        write_in_full(STDOUT_FILENO, output.buf, output.len);
 710        return 0;
 711}