Andrew's git / gitweb.git / builtin/fmt-merge-msg.c
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builtin / fmt-merge-msg.con commit Merge branch 'km/config-grammofix' into maint (67476f5)
   1#include "builtin.h"
   2#include "cache.h"
   3#include "refs.h"
   4#include "commit.h"
   5#include "diff.h"
   6#include "revision.h"
   7#include "tag.h"
   8#include "string-list.h"
   9#include "branch.h"
  10#include "fmt-merge-msg.h"
  11#include "gpg-interface.h"
  12
  13static const char * const fmt_merge_msg_usage[] = {
  14        N_("git fmt-merge-msg [-m <message>] [--log[=<n>] | --no-log] [--file <file>]"),
  15        NULL
  16};
  17
  18static int use_branch_desc;
  19
  20int fmt_merge_msg_config(const char *key, const char *value, void *cb)
  21{
  22        if (!strcmp(key, "merge.log") || !strcmp(key, "merge.summary")) {
  23                int is_bool;
  24                merge_log_config = git_config_bool_or_int(key, value, &is_bool);
  25                if (!is_bool && merge_log_config < 0)
  26                        return error("%s: negative length %s", key, value);
  27                if (is_bool && merge_log_config)
  28                        merge_log_config = DEFAULT_MERGE_LOG_LEN;
  29        } else if (!strcmp(key, "merge.branchdesc")) {
  30                use_branch_desc = git_config_bool(key, value);
  31        } else {
  32                return git_default_config(key, value, cb);
  33        }
  34        return 0;
  35}
  36
  37/* merge data per repository where the merged tips came from */
  38struct src_data {
  39        struct string_list branch, tag, r_branch, generic;
  40        int head_status;
  41};
  42
  43struct origin_data {
  44        unsigned char sha1[20];
  45        unsigned is_local_branch:1;
  46};
  47
  48static void init_src_data(struct src_data *data)
  49{
  50        data->branch.strdup_strings = 1;
  51        data->tag.strdup_strings = 1;
  52        data->r_branch.strdup_strings = 1;
  53        data->generic.strdup_strings = 1;
  54}
  55
  56static struct string_list srcs = STRING_LIST_INIT_DUP;
  57static struct string_list origins = STRING_LIST_INIT_DUP;
  58
  59struct merge_parents {
  60        int alloc, nr;
  61        struct merge_parent {
  62                unsigned char given[20];
  63                unsigned char commit[20];
  64                unsigned char used;
  65        } *item;
  66};
  67
  68/*
  69 * I know, I know, this is inefficient, but you won't be pulling and merging
  70 * hundreds of heads at a time anyway.
  71 */
  72static struct merge_parent *find_merge_parent(struct merge_parents *table,
  73                                              unsigned char *given,
  74                                              unsigned char *commit)
  75{
  76        int i;
  77        for (i = 0; i < table->nr; i++) {
  78                if (given && hashcmp(table->item[i].given, given))
  79                        continue;
  80                if (commit && hashcmp(table->item[i].commit, commit))
  81                        continue;
  82                return &table->item[i];
  83        }
  84        return NULL;
  85}
  86
  87static void add_merge_parent(struct merge_parents *table,
  88                             unsigned char *given,
  89                             unsigned char *commit)
  90{
  91        if (table->nr && find_merge_parent(table, given, commit))
  92                return;
  93        ALLOC_GROW(table->item, table->nr + 1, table->alloc);
  94        hashcpy(table->item[table->nr].given, given);
  95        hashcpy(table->item[table->nr].commit, commit);
  96        table->item[table->nr].used = 0;
  97        table->nr++;
  98}
  99
 100static int handle_line(char *line, struct merge_parents *merge_parents)
 101{
 102        int i, len = strlen(line);
 103        struct origin_data *origin_data;
 104        char *src;
 105        const char *origin;
 106        struct src_data *src_data;
 107        struct string_list_item *item;
 108        int pulling_head = 0;
 109        unsigned char sha1[20];
 110
 111        if (len < 43 || line[40] != '\t')
 112                return 1;
 113
 114        if (starts_with(line + 41, "not-for-merge"))
 115                return 0;
 116
 117        if (line[41] != '\t')
 118                return 2;
 119
 120        i = get_sha1_hex(line, sha1);
 121        if (i)
 122                return 3;
 123
 124        if (!find_merge_parent(merge_parents, sha1, NULL))
 125                return 0; /* subsumed by other parents */
 126
 127        origin_data = xcalloc(1, sizeof(struct origin_data));
 128        hashcpy(origin_data->sha1, sha1);
 129
 130        if (line[len - 1] == '\n')
 131                line[len - 1] = 0;
 132        line += 42;
 133
 134        /*
 135         * At this point, line points at the beginning of comment e.g.
 136         * "branch 'frotz' of git://that/repository.git".
 137         * Find the repository name and point it with src.
 138         */
 139        src = strstr(line, " of ");
 140        if (src) {
 141                *src = 0;
 142                src += 4;
 143                pulling_head = 0;
 144        } else {
 145                src = line;
 146                pulling_head = 1;
 147        }
 148
 149        item = unsorted_string_list_lookup(&srcs, src);
 150        if (!item) {
 151                item = string_list_append(&srcs, src);
 152                item->util = xcalloc(1, sizeof(struct src_data));
 153                init_src_data(item->util);
 154        }
 155        src_data = item->util;
 156
 157        if (pulling_head) {
 158                origin = src;
 159                src_data->head_status |= 1;
 160        } else if (starts_with(line, "branch ")) {
 161                origin_data->is_local_branch = 1;
 162                origin = line + 7;
 163                string_list_append(&src_data->branch, origin);
 164                src_data->head_status |= 2;
 165        } else if (starts_with(line, "tag ")) {
 166                origin = line;
 167                string_list_append(&src_data->tag, origin + 4);
 168                src_data->head_status |= 2;
 169        } else if (skip_prefix(line, "remote-tracking branch ", &origin)) {
 170                string_list_append(&src_data->r_branch, origin);
 171                src_data->head_status |= 2;
 172        } else {
 173                origin = src;
 174                string_list_append(&src_data->generic, line);
 175                src_data->head_status |= 2;
 176        }
 177
 178        if (!strcmp(".", src) || !strcmp(src, origin)) {
 179                int len = strlen(origin);
 180                if (origin[0] == '\'' && origin[len - 1] == '\'')
 181                        origin = xmemdupz(origin + 1, len - 2);
 182        } else
 183                origin = xstrfmt("%s of %s", origin, src);
 184        if (strcmp(".", src))
 185                origin_data->is_local_branch = 0;
 186        string_list_append(&origins, origin)->util = origin_data;
 187        return 0;
 188}
 189
 190static void print_joined(const char *singular, const char *plural,
 191                struct string_list *list, struct strbuf *out)
 192{
 193        if (list->nr == 0)
 194                return;
 195        if (list->nr == 1) {
 196                strbuf_addf(out, "%s%s", singular, list->items[0].string);
 197        } else {
 198                int i;
 199                strbuf_addstr(out, plural);
 200                for (i = 0; i < list->nr - 1; i++)
 201                        strbuf_addf(out, "%s%s", i > 0 ? ", " : "",
 202                                    list->items[i].string);
 203                strbuf_addf(out, " and %s", list->items[list->nr - 1].string);
 204        }
 205}
 206
 207static void add_branch_desc(struct strbuf *out, const char *name)
 208{
 209        struct strbuf desc = STRBUF_INIT;
 210
 211        if (!read_branch_desc(&desc, name)) {
 212                const char *bp = desc.buf;
 213                while (*bp) {
 214                        const char *ep = strchrnul(bp, '\n');
 215                        if (*ep)
 216                                ep++;
 217                        strbuf_addf(out, "  : %.*s", (int)(ep - bp), bp);
 218                        bp = ep;
 219                }
 220                strbuf_complete_line(out);
 221        }
 222        strbuf_release(&desc);
 223}
 224
 225#define util_as_integral(elem) ((intptr_t)((elem)->util))
 226
 227static void record_person_from_buf(int which, struct string_list *people,
 228                                   const char *buffer)
 229{
 230        char *name_buf, *name, *name_end;
 231        struct string_list_item *elem;
 232        const char *field;
 233
 234        field = (which == 'a') ? "\nauthor " : "\ncommitter ";
 235        name = strstr(buffer, field);
 236        if (!name)
 237                return;
 238        name += strlen(field);
 239        name_end = strchrnul(name, '<');
 240        if (*name_end)
 241                name_end--;
 242        while (isspace(*name_end) && name <= name_end)
 243                name_end--;
 244        if (name_end < name)
 245                return;
 246        name_buf = xmemdupz(name, name_end - name + 1);
 247
 248        elem = string_list_lookup(people, name_buf);
 249        if (!elem) {
 250                elem = string_list_insert(people, name_buf);
 251                elem->util = (void *)0;
 252        }
 253        elem->util = (void*)(util_as_integral(elem) + 1);
 254        free(name_buf);
 255}
 256
 257
 258static void record_person(int which, struct string_list *people,
 259                          struct commit *commit)
 260{
 261        const char *buffer = get_commit_buffer(commit, NULL);
 262        record_person_from_buf(which, people, buffer);
 263        unuse_commit_buffer(commit, buffer);
 264}
 265
 266static int cmp_string_list_util_as_integral(const void *a_, const void *b_)
 267{
 268        const struct string_list_item *a = a_, *b = b_;
 269        return util_as_integral(b) - util_as_integral(a);
 270}
 271
 272static void add_people_count(struct strbuf *out, struct string_list *people)
 273{
 274        if (people->nr == 1)
 275                strbuf_addstr(out, people->items[0].string);
 276        else if (people->nr == 2)
 277                strbuf_addf(out, "%s (%d) and %s (%d)",
 278                            people->items[0].string,
 279                            (int)util_as_integral(&people->items[0]),
 280                            people->items[1].string,
 281                            (int)util_as_integral(&people->items[1]));
 282        else if (people->nr)
 283                strbuf_addf(out, "%s (%d) and others",
 284                            people->items[0].string,
 285                            (int)util_as_integral(&people->items[0]));
 286}
 287
 288static void credit_people(struct strbuf *out,
 289                          struct string_list *them,
 290                          int kind)
 291{
 292        const char *label;
 293        const char *me;
 294
 295        if (kind == 'a') {
 296                label = "By";
 297                me = git_author_info(IDENT_NO_DATE);
 298        } else {
 299                label = "Via";
 300                me = git_committer_info(IDENT_NO_DATE);
 301        }
 302
 303        if (!them->nr ||
 304            (them->nr == 1 &&
 305             me &&
 306             skip_prefix(me, them->items->string, &me) &&
 307             starts_with(me, " <")))
 308                return;
 309        strbuf_addf(out, "\n%c %s ", comment_line_char, label);
 310        add_people_count(out, them);
 311}
 312
 313static void add_people_info(struct strbuf *out,
 314                            struct string_list *authors,
 315                            struct string_list *committers)
 316{
 317        QSORT(authors->items, authors->nr,
 318              cmp_string_list_util_as_integral);
 319        QSORT(committers->items, committers->nr,
 320              cmp_string_list_util_as_integral);
 321
 322        credit_people(out, authors, 'a');
 323        credit_people(out, committers, 'c');
 324}
 325
 326static void shortlog(const char *name,
 327                     struct origin_data *origin_data,
 328                     struct commit *head,
 329                     struct rev_info *rev,
 330                     struct fmt_merge_msg_opts *opts,
 331                     struct strbuf *out)
 332{
 333        int i, count = 0;
 334        struct commit *commit;
 335        struct object *branch;
 336        struct string_list subjects = STRING_LIST_INIT_DUP;
 337        struct string_list authors = STRING_LIST_INIT_DUP;
 338        struct string_list committers = STRING_LIST_INIT_DUP;
 339        int flags = UNINTERESTING | TREESAME | SEEN | SHOWN | ADDED;
 340        struct strbuf sb = STRBUF_INIT;
 341        const unsigned char *sha1 = origin_data->sha1;
 342        int limit = opts->shortlog_len;
 343
 344        branch = deref_tag(parse_object(sha1), sha1_to_hex(sha1), 40);
 345        if (!branch || branch->type != OBJ_COMMIT)
 346                return;
 347
 348        setup_revisions(0, NULL, rev, NULL);
 349        add_pending_object(rev, branch, name);
 350        add_pending_object(rev, &head->object, "^HEAD");
 351        head->object.flags |= UNINTERESTING;
 352        if (prepare_revision_walk(rev))
 353                die("revision walk setup failed");
 354        while ((commit = get_revision(rev)) != NULL) {
 355                struct pretty_print_context ctx = {0};
 356
 357                if (commit->parents && commit->parents->next) {
 358                        /* do not list a merge but count committer */
 359                        if (opts->credit_people)
 360                                record_person('c', &committers, commit);
 361                        continue;
 362                }
 363                if (!count && opts->credit_people)
 364                        /* the 'tip' committer */
 365                        record_person('c', &committers, commit);
 366                if (opts->credit_people)
 367                        record_person('a', &authors, commit);
 368                count++;
 369                if (subjects.nr > limit)
 370                        continue;
 371
 372                format_commit_message(commit, "%s", &sb, &ctx);
 373                strbuf_ltrim(&sb);
 374
 375                if (!sb.len)
 376                        string_list_append(&subjects,
 377                                           oid_to_hex(&commit->object.oid));
 378                else
 379                        string_list_append(&subjects, strbuf_detach(&sb, NULL));
 380        }
 381
 382        if (opts->credit_people)
 383                add_people_info(out, &authors, &committers);
 384        if (count > limit)
 385                strbuf_addf(out, "\n* %s: (%d commits)\n", name, count);
 386        else
 387                strbuf_addf(out, "\n* %s:\n", name);
 388
 389        if (origin_data->is_local_branch && use_branch_desc)
 390                add_branch_desc(out, name);
 391
 392        for (i = 0; i < subjects.nr; i++)
 393                if (i >= limit)
 394                        strbuf_addstr(out, "  ...\n");
 395                else
 396                        strbuf_addf(out, "  %s\n", subjects.items[i].string);
 397
 398        clear_commit_marks((struct commit *)branch, flags);
 399        clear_commit_marks(head, flags);
 400        free_commit_list(rev->commits);
 401        rev->commits = NULL;
 402        rev->pending.nr = 0;
 403
 404        string_list_clear(&authors, 0);
 405        string_list_clear(&committers, 0);
 406        string_list_clear(&subjects, 0);
 407}
 408
 409static void fmt_merge_msg_title(struct strbuf *out,
 410        const char *current_branch) {
 411        int i = 0;
 412        char *sep = "";
 413
 414        strbuf_addstr(out, "Merge ");
 415        for (i = 0; i < srcs.nr; i++) {
 416                struct src_data *src_data = srcs.items[i].util;
 417                const char *subsep = "";
 418
 419                strbuf_addstr(out, sep);
 420                sep = "; ";
 421
 422                if (src_data->head_status == 1) {
 423                        strbuf_addstr(out, srcs.items[i].string);
 424                        continue;
 425                }
 426                if (src_data->head_status == 3) {
 427                        subsep = ", ";
 428                        strbuf_addstr(out, "HEAD");
 429                }
 430                if (src_data->branch.nr) {
 431                        strbuf_addstr(out, subsep);
 432                        subsep = ", ";
 433                        print_joined("branch ", "branches ", &src_data->branch,
 434                                        out);
 435                }
 436                if (src_data->r_branch.nr) {
 437                        strbuf_addstr(out, subsep);
 438                        subsep = ", ";
 439                        print_joined("remote-tracking branch ", "remote-tracking branches ",
 440                                        &src_data->r_branch, out);
 441                }
 442                if (src_data->tag.nr) {
 443                        strbuf_addstr(out, subsep);
 444                        subsep = ", ";
 445                        print_joined("tag ", "tags ", &src_data->tag, out);
 446                }
 447                if (src_data->generic.nr) {
 448                        strbuf_addstr(out, subsep);
 449                        print_joined("commit ", "commits ", &src_data->generic,
 450                                        out);
 451                }
 452                if (strcmp(".", srcs.items[i].string))
 453                        strbuf_addf(out, " of %s", srcs.items[i].string);
 454        }
 455
 456        if (!strcmp("master", current_branch))
 457                strbuf_addch(out, '\n');
 458        else
 459                strbuf_addf(out, " into %s\n", current_branch);
 460}
 461
 462static void fmt_tag_signature(struct strbuf *tagbuf,
 463                              struct strbuf *sig,
 464                              const char *buf,
 465                              unsigned long len)
 466{
 467        const char *tag_body = strstr(buf, "\n\n");
 468        if (tag_body) {
 469                tag_body += 2;
 470                strbuf_add(tagbuf, tag_body, buf + len - tag_body);
 471        }
 472        strbuf_complete_line(tagbuf);
 473        if (sig->len) {
 474                strbuf_addch(tagbuf, '\n');
 475                strbuf_add_commented_lines(tagbuf, sig->buf, sig->len);
 476        }
 477}
 478
 479static void fmt_merge_msg_sigs(struct strbuf *out)
 480{
 481        int i, tag_number = 0, first_tag = 0;
 482        struct strbuf tagbuf = STRBUF_INIT;
 483
 484        for (i = 0; i < origins.nr; i++) {
 485                unsigned char *sha1 = origins.items[i].util;
 486                enum object_type type;
 487                unsigned long size, len;
 488                char *buf = read_sha1_file(sha1, &type, &size);
 489                struct strbuf sig = STRBUF_INIT;
 490
 491                if (!buf || type != OBJ_TAG)
 492                        goto next;
 493                len = parse_signature(buf, size);
 494
 495                if (size == len)
 496                        ; /* merely annotated */
 497                else if (verify_signed_buffer(buf, len, buf + len, size - len, &sig, NULL)) {
 498                        if (!sig.len)
 499                                strbuf_addstr(&sig, "gpg verification failed.\n");
 500                }
 501
 502                if (!tag_number++) {
 503                        fmt_tag_signature(&tagbuf, &sig, buf, len);
 504                        first_tag = i;
 505                } else {
 506                        if (tag_number == 2) {
 507                                struct strbuf tagline = STRBUF_INIT;
 508                                strbuf_addch(&tagline, '\n');
 509                                strbuf_add_commented_lines(&tagline,
 510                                                origins.items[first_tag].string,
 511                                                strlen(origins.items[first_tag].string));
 512                                strbuf_insert(&tagbuf, 0, tagline.buf,
 513                                              tagline.len);
 514                                strbuf_release(&tagline);
 515                        }
 516                        strbuf_addch(&tagbuf, '\n');
 517                        strbuf_add_commented_lines(&tagbuf,
 518                                        origins.items[i].string,
 519                                        strlen(origins.items[i].string));
 520                        fmt_tag_signature(&tagbuf, &sig, buf, len);
 521                }
 522                strbuf_release(&sig);
 523        next:
 524                free(buf);
 525        }
 526        if (tagbuf.len) {
 527                strbuf_addch(out, '\n');
 528                strbuf_addbuf(out, &tagbuf);
 529        }
 530        strbuf_release(&tagbuf);
 531}
 532
 533static void find_merge_parents(struct merge_parents *result,
 534                               struct strbuf *in, unsigned char *head)
 535{
 536        struct commit_list *parents;
 537        struct commit *head_commit;
 538        int pos = 0, i, j;
 539
 540        parents = NULL;
 541        while (pos < in->len) {
 542                int len;
 543                char *p = in->buf + pos;
 544                char *newline = strchr(p, '\n');
 545                unsigned char sha1[20];
 546                struct commit *parent;
 547                struct object *obj;
 548
 549                len = newline ? newline - p : strlen(p);
 550                pos += len + !!newline;
 551
 552                if (len < 43 ||
 553                    get_sha1_hex(p, sha1) ||
 554                    p[40] != '\t' ||
 555                    p[41] != '\t')
 556                        continue; /* skip not-for-merge */
 557                /*
 558                 * Do not use get_merge_parent() here; we do not have
 559                 * "name" here and we do not want to contaminate its
 560                 * util field yet.
 561                 */
 562                obj = parse_object(sha1);
 563                parent = (struct commit *)peel_to_type(NULL, 0, obj, OBJ_COMMIT);
 564                if (!parent)
 565                        continue;
 566                commit_list_insert(parent, &parents);
 567                add_merge_parent(result, obj->oid.hash, parent->object.oid.hash);
 568        }
 569        head_commit = lookup_commit(head);
 570        if (head_commit)
 571                commit_list_insert(head_commit, &parents);
 572        parents = reduce_heads(parents);
 573
 574        while (parents) {
 575                struct commit *cmit = pop_commit(&parents);
 576                for (i = 0; i < result->nr; i++)
 577                        if (!hashcmp(result->item[i].commit, cmit->object.oid.hash))
 578                                result->item[i].used = 1;
 579        }
 580
 581        for (i = j = 0; i < result->nr; i++) {
 582                if (result->item[i].used) {
 583                        if (i != j)
 584                                result->item[j] = result->item[i];
 585                        j++;
 586                }
 587        }
 588        result->nr = j;
 589}
 590
 591int fmt_merge_msg(struct strbuf *in, struct strbuf *out,
 592                  struct fmt_merge_msg_opts *opts)
 593{
 594        int i = 0, pos = 0;
 595        unsigned char head_sha1[20];
 596        const char *current_branch;
 597        void *current_branch_to_free;
 598        struct merge_parents merge_parents;
 599
 600        memset(&merge_parents, 0, sizeof(merge_parents));
 601
 602        /* get current branch */
 603        current_branch = current_branch_to_free =
 604                resolve_refdup("HEAD", RESOLVE_REF_READING, head_sha1, NULL);
 605        if (!current_branch)
 606                die("No current branch");
 607        if (starts_with(current_branch, "refs/heads/"))
 608                current_branch += 11;
 609
 610        find_merge_parents(&merge_parents, in, head_sha1);
 611
 612        /* get a line */
 613        while (pos < in->len) {
 614                int len;
 615                char *newline, *p = in->buf + pos;
 616
 617                newline = strchr(p, '\n');
 618                len = newline ? newline - p : strlen(p);
 619                pos += len + !!newline;
 620                i++;
 621                p[len] = 0;
 622                if (handle_line(p, &merge_parents))
 623                        die ("Error in line %d: %.*s", i, len, p);
 624        }
 625
 626        if (opts->add_title && srcs.nr)
 627                fmt_merge_msg_title(out, current_branch);
 628
 629        if (origins.nr)
 630                fmt_merge_msg_sigs(out);
 631
 632        if (opts->shortlog_len) {
 633                struct commit *head;
 634                struct rev_info rev;
 635
 636                head = lookup_commit_or_die(head_sha1, "HEAD");
 637                init_revisions(&rev, NULL);
 638                rev.commit_format = CMIT_FMT_ONELINE;
 639                rev.ignore_merges = 1;
 640                rev.limited = 1;
 641
 642                strbuf_complete_line(out);
 643
 644                for (i = 0; i < origins.nr; i++)
 645                        shortlog(origins.items[i].string,
 646                                 origins.items[i].util,
 647                                 head, &rev, opts, out);
 648        }
 649
 650        strbuf_complete_line(out);
 651        free(current_branch_to_free);
 652        free(merge_parents.item);
 653        return 0;
 654}
 655
 656int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
 657{
 658        const char *inpath = NULL;
 659        const char *message = NULL;
 660        int shortlog_len = -1;
 661        struct option options[] = {
 662                { OPTION_INTEGER, 0, "log", &shortlog_len, N_("n"),
 663                  N_("populate log with at most <n> entries from shortlog"),
 664                  PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
 665                { OPTION_INTEGER, 0, "summary", &shortlog_len, N_("n"),
 666                  N_("alias for --log (deprecated)"),
 667                  PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, NULL,
 668                  DEFAULT_MERGE_LOG_LEN },
 669                OPT_STRING('m', "message", &message, N_("text"),
 670                        N_("use <text> as start of message")),
 671                OPT_FILENAME('F', "file", &inpath, N_("file to read from")),
 672                OPT_END()
 673        };
 674
 675        FILE *in = stdin;
 676        struct strbuf input = STRBUF_INIT, output = STRBUF_INIT;
 677        int ret;
 678        struct fmt_merge_msg_opts opts;
 679
 680        git_config(fmt_merge_msg_config, NULL);
 681        argc = parse_options(argc, argv, prefix, options, fmt_merge_msg_usage,
 682                             0);
 683        if (argc > 0)
 684                usage_with_options(fmt_merge_msg_usage, options);
 685        if (shortlog_len < 0)
 686                shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;
 687
 688        if (inpath && strcmp(inpath, "-")) {
 689                in = fopen(inpath, "r");
 690                if (!in)
 691                        die_errno("cannot open '%s'", inpath);
 692        }
 693
 694        if (strbuf_read(&input, fileno(in), 0) < 0)
 695                die_errno("could not read input file");
 696
 697        if (message)
 698                strbuf_addstr(&output, message);
 699
 700        memset(&opts, 0, sizeof(opts));
 701        opts.add_title = !message;
 702        opts.credit_people = 1;
 703        opts.shortlog_len = shortlog_len;
 704
 705        ret = fmt_merge_msg(&input, &output, &opts);
 706        if (ret)
 707                return ret;
 708        write_in_full(STDOUT_FILENO, output.buf, output.len);
 709        return 0;
 710}