builtin/fmt-merge-msg.c

   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
  13 static 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
  18 static int use_branch_desc;
  19
  20 int 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 */
  38 struct src_data {
  39         struct string_list branch, tag, r_branch, generic;
  40         int head_status;
  41 };
  42
  43 struct origin_data {
  44         unsigned char sha1[20];
  45         unsigned is_local_branch:1;
  46 };
  47
  48 static 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
  56 static struct string_list srcs = STRING_LIST_INIT_DUP;
  57 static struct string_list origins = STRING_LIST_INIT_DUP;
  58
  59 struct 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  */
  72 static 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
  87 static 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
 100 static 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
 190 static 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
 207 static 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
 227 static 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
 258 static 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
 266 static 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
 272 static 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
 288 static 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
 313 static void add_people_info(struct strbuf *out,
 314                             struct string_list *authors,
 315                             struct string_list *committers)
 316 {
 317         if (authors->nr)
 318                 qsort(authors->items,
 319                       authors->nr, sizeof(authors->items[0]),
 320                       cmp_string_list_util_as_integral);
 321         if (committers->nr)
 322                 qsort(committers->items,
 323                       committers->nr, sizeof(committers->items[0]),
 324                       cmp_string_list_util_as_integral);
 325
 326         credit_people(out, authors, 'a');
 327         credit_people(out, committers, 'c');
 328 }
 329
 330 static void shortlog(const char *name,
 331                      struct origin_data *origin_data,
 332                      struct commit *head,
 333                      struct rev_info *rev,
 334                      struct fmt_merge_msg_opts *opts,
 335                      struct strbuf *out)
 336 {
 337         int i, count = 0;
 338         struct commit *commit;
 339         struct object *branch;
 340         struct string_list subjects = STRING_LIST_INIT_DUP;
 341         struct string_list authors = STRING_LIST_INIT_DUP;
 342         struct string_list committers = STRING_LIST_INIT_DUP;
 343         int flags = UNINTERESTING | TREESAME | SEEN | SHOWN | ADDED;
 344         struct strbuf sb = STRBUF_INIT;
 345         const unsigned char *sha1 = origin_data->sha1;
 346         int limit = opts->shortlog_len;
 347
 348         branch = deref_tag(parse_object(sha1), sha1_to_hex(sha1), 40);
 349         if (!branch || branch->type != OBJ_COMMIT)
 350                 return;
 351
 352         setup_revisions(0, NULL, rev, NULL);
 353         add_pending_object(rev, branch, name);
 354         add_pending_object(rev, &head->object, "^HEAD");
 355         head->object.flags |= UNINTERESTING;
 356         if (prepare_revision_walk(rev))
 357                 die("revision walk setup failed");
 358         while ((commit = get_revision(rev)) != NULL) {
 359                 struct pretty_print_context ctx = {0};
 360
 361                 if (commit->parents && commit->parents->next) {
 362                         /* do not list a merge but count committer */
 363                         if (opts->credit_people)
 364                                 record_person('c', &committers, commit);
 365                         continue;
 366                 }
 367                 if (!count && opts->credit_people)
 368                         /* the 'tip' committer */
 369                         record_person('c', &committers, commit);
 370                 if (opts->credit_people)
 371                         record_person('a', &authors, commit);
 372                 count++;
 373                 if (subjects.nr > limit)
 374                         continue;
 375
 376                 format_commit_message(commit, "%s", &sb, &ctx);
 377                 strbuf_ltrim(&sb);
 378
 379                 if (!sb.len)
 380                         string_list_append(&subjects,
 381                                            oid_to_hex(&commit->object.oid));
 382                 else
 383                         string_list_append(&subjects, strbuf_detach(&sb, NULL));
 384         }
 385
 386         if (opts->credit_people)
 387                 add_people_info(out, &authors, &committers);
 388         if (count > limit)
 389                 strbuf_addf(out, "\n* %s: (%d commits)\n", name, count);
 390         else
 391                 strbuf_addf(out, "\n* %s:\n", name);
 392
 393         if (origin_data->is_local_branch && use_branch_desc)
 394                 add_branch_desc(out, name);
 395
 396         for (i = 0; i < subjects.nr; i++)
 397                 if (i >= limit)
 398                         strbuf_addf(out, "  ...\n");
 399                 else
 400                         strbuf_addf(out, "  %s\n", subjects.items[i].string);
 401
 402         clear_commit_marks((struct commit *)branch, flags);
 403         clear_commit_marks(head, flags);
 404         free_commit_list(rev->commits);
 405         rev->commits = NULL;
 406         rev->pending.nr = 0;
 407
 408         string_list_clear(&authors, 0);
 409         string_list_clear(&committers, 0);
 410         string_list_clear(&subjects, 0);
 411 }
 412
 413 static void fmt_merge_msg_title(struct strbuf *out,
 414         const char *current_branch) {
 415         int i = 0;
 416         char *sep = "";
 417
 418         strbuf_addstr(out, "Merge ");
 419         for (i = 0; i < srcs.nr; i++) {
 420                 struct src_data *src_data = srcs.items[i].util;
 421                 const char *subsep = "";
 422
 423                 strbuf_addstr(out, sep);
 424                 sep = "; ";
 425
 426                 if (src_data->head_status == 1) {
 427                         strbuf_addstr(out, srcs.items[i].string);
 428                         continue;
 429                 }
 430                 if (src_data->head_status == 3) {
 431                         subsep = ", ";
 432                         strbuf_addstr(out, "HEAD");
 433                 }
 434                 if (src_data->branch.nr) {
 435                         strbuf_addstr(out, subsep);
 436                         subsep = ", ";
 437                         print_joined("branch ", "branches ", &src_data->branch,
 438                                         out);
 439                 }
 440                 if (src_data->r_branch.nr) {
 441                         strbuf_addstr(out, subsep);
 442                         subsep = ", ";
 443                         print_joined("remote-tracking branch ", "remote-tracking branches ",
 444                                         &src_data->r_branch, out);
 445                 }
 446                 if (src_data->tag.nr) {
 447                         strbuf_addstr(out, subsep);
 448                         subsep = ", ";
 449                         print_joined("tag ", "tags ", &src_data->tag, out);
 450                 }
 451                 if (src_data->generic.nr) {
 452                         strbuf_addstr(out, subsep);
 453                         print_joined("commit ", "commits ", &src_data->generic,
 454                                         out);
 455                 }
 456                 if (strcmp(".", srcs.items[i].string))
 457                         strbuf_addf(out, " of %s", srcs.items[i].string);
 458         }
 459
 460         if (!strcmp("master", current_branch))
 461                 strbuf_addch(out, '\n');
 462         else
 463                 strbuf_addf(out, " into %s\n", current_branch);
 464 }
 465
 466 static void fmt_tag_signature(struct strbuf *tagbuf,
 467                               struct strbuf *sig,
 468                               const char *buf,
 469                               unsigned long len)
 470 {
 471         const char *tag_body = strstr(buf, "\n\n");
 472         if (tag_body) {
 473                 tag_body += 2;
 474                 strbuf_add(tagbuf, tag_body, buf + len - tag_body);
 475         }
 476         strbuf_complete_line(tagbuf);
 477         if (sig->len) {
 478                 strbuf_addch(tagbuf, '\n');
 479                 strbuf_add_commented_lines(tagbuf, sig->buf, sig->len);
 480         }
 481 }
 482
 483 static void fmt_merge_msg_sigs(struct strbuf *out)
 484 {
 485         int i, tag_number = 0, first_tag = 0;
 486         struct strbuf tagbuf = STRBUF_INIT;
 487
 488         for (i = 0; i < origins.nr; i++) {
 489                 unsigned char *sha1 = origins.items[i].util;
 490                 enum object_type type;
 491                 unsigned long size, len;
 492                 char *buf = read_sha1_file(sha1, &type, &size);
 493                 struct strbuf sig = STRBUF_INIT;
 494
 495                 if (!buf || type != OBJ_TAG)
 496                         goto next;
 497                 len = parse_signature(buf, size);
 498
 499                 if (size == len)
 500                         ; /* merely annotated */
 501                 else if (verify_signed_buffer(buf, len, buf + len, size - len, &sig, NULL)) {
 502                         if (!sig.len)
 503                                 strbuf_addstr(&sig, "gpg verification failed.\n");
 504                 }
 505
 506                 if (!tag_number++) {
 507                         fmt_tag_signature(&tagbuf, &sig, buf, len);
 508                         first_tag = i;
 509                 } else {
 510                         if (tag_number == 2) {
 511                                 struct strbuf tagline = STRBUF_INIT;
 512                                 strbuf_addch(&tagline, '\n');
 513                                 strbuf_add_commented_lines(&tagline,
 514                                                 origins.items[first_tag].string,
 515                                                 strlen(origins.items[first_tag].string));
 516                                 strbuf_insert(&tagbuf, 0, tagline.buf,
 517                                               tagline.len);
 518                                 strbuf_release(&tagline);
 519                         }
 520                         strbuf_addch(&tagbuf, '\n');
 521                         strbuf_add_commented_lines(&tagbuf,
 522                                         origins.items[i].string,
 523                                         strlen(origins.items[i].string));
 524                         fmt_tag_signature(&tagbuf, &sig, buf, len);
 525                 }
 526                 strbuf_release(&sig);
 527         next:
 528                 free(buf);
 529         }
 530         if (tagbuf.len) {
 531                 strbuf_addch(out, '\n');
 532                 strbuf_addbuf(out, &tagbuf);
 533         }
 534         strbuf_release(&tagbuf);
 535 }
 536
 537 static void find_merge_parents(struct merge_parents *result,
 538                                struct strbuf *in, unsigned char *head)
 539 {
 540         struct commit_list *parents;
 541         struct commit *head_commit;
 542         int pos = 0, i, j;
 543
 544         parents = NULL;
 545         while (pos < in->len) {
 546                 int len;
 547                 char *p = in->buf + pos;
 548                 char *newline = strchr(p, '\n');
 549                 unsigned char sha1[20];
 550                 struct commit *parent;
 551                 struct object *obj;
 552
 553                 len = newline ? newline - p : strlen(p);
 554                 pos += len + !!newline;
 555
 556                 if (len < 43 ||
 557                     get_sha1_hex(p, sha1) ||
 558                     p[40] != '\t' ||
 559                     p[41] != '\t')
 560                         continue; /* skip not-for-merge */
 561                 /*
 562                  * Do not use get_merge_parent() here; we do not have
 563                  * "name" here and we do not want to contaminate its
 564                  * util field yet.
 565                  */
 566                 obj = parse_object(sha1);
 567                 parent = (struct commit *)peel_to_type(NULL, 0, obj, OBJ_COMMIT);
 568                 if (!parent)
 569                         continue;
 570                 commit_list_insert(parent, &parents);
 571                 add_merge_parent(result, obj->oid.hash, parent->object.oid.hash);
 572         }
 573         head_commit = lookup_commit(head);
 574         if (head_commit)
 575                 commit_list_insert(head_commit, &parents);
 576         parents = reduce_heads(parents);
 577
 578         while (parents) {
 579                 struct commit *cmit = pop_commit(&parents);
 580                 for (i = 0; i < result->nr; i++)
 581                         if (!hashcmp(result->item[i].commit, cmit->object.oid.hash))
 582                                 result->item[i].used = 1;
 583         }
 584
 585         for (i = j = 0; i < result->nr; i++) {
 586                 if (result->item[i].used) {
 587                         if (i != j)
 588                                 result->item[j] = result->item[i];
 589                         j++;
 590                 }
 591         }
 592         result->nr = j;
 593 }
 594
 595 int fmt_merge_msg(struct strbuf *in, struct strbuf *out,
 596                   struct fmt_merge_msg_opts *opts)
 597 {
 598         int i = 0, pos = 0;
 599         unsigned char head_sha1[20];
 600         const char *current_branch;
 601         void *current_branch_to_free;
 602         struct merge_parents merge_parents;
 603
 604         memset(&merge_parents, 0, sizeof(merge_parents));
 605
 606         /* get current branch */
 607         current_branch = current_branch_to_free =
 608                 resolve_refdup("HEAD", RESOLVE_REF_READING, head_sha1, NULL);
 609         if (!current_branch)
 610                 die("No current branch");
 611         if (starts_with(current_branch, "refs/heads/"))
 612                 current_branch += 11;
 613
 614         find_merge_parents(&merge_parents, in, head_sha1);
 615
 616         /* get a line */
 617         while (pos < in->len) {
 618                 int len;
 619                 char *newline, *p = in->buf + pos;
 620
 621                 newline = strchr(p, '\n');
 622                 len = newline ? newline - p : strlen(p);
 623                 pos += len + !!newline;
 624                 i++;
 625                 p[len] = 0;
 626                 if (handle_line(p, &merge_parents))
 627                         die ("Error in line %d: %.*s", i, len, p);
 628         }
 629
 630         if (opts->add_title && srcs.nr)
 631                 fmt_merge_msg_title(out, current_branch);
 632
 633         if (origins.nr)
 634                 fmt_merge_msg_sigs(out);
 635
 636         if (opts->shortlog_len) {
 637                 struct commit *head;
 638                 struct rev_info rev;
 639
 640                 head = lookup_commit_or_die(head_sha1, "HEAD");
 641                 init_revisions(&rev, NULL);
 642                 rev.commit_format = CMIT_FMT_ONELINE;
 643                 rev.ignore_merges = 1;
 644                 rev.limited = 1;
 645
 646                 strbuf_complete_line(out);
 647
 648                 for (i = 0; i < origins.nr; i++)
 649                         shortlog(origins.items[i].string,
 650                                  origins.items[i].util,
 651                                  head, &rev, opts, out);
 652         }
 653
 654         strbuf_complete_line(out);
 655         free(current_branch_to_free);
 656         free(merge_parents.item);
 657         return 0;
 658 }
 659
 660 int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
 661 {
 662         const char *inpath = NULL;
 663         const char *message = NULL;
 664         int shortlog_len = -1;
 665         struct option options[] = {
 666                 { OPTION_INTEGER, 0, "log", &shortlog_len, N_("n"),
 667                   N_("populate log with at most <n> entries from shortlog"),
 668                   PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
 669                 { OPTION_INTEGER, 0, "summary", &shortlog_len, N_("n"),
 670                   N_("alias for --log (deprecated)"),
 671                   PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, NULL,
 672                   DEFAULT_MERGE_LOG_LEN },
 673                 OPT_STRING('m', "message", &message, N_("text"),
 674                         N_("use <text> as start of message")),
 675                 OPT_FILENAME('F', "file", &inpath, N_("file to read from")),
 676                 OPT_END()
 677         };
 678
 679         FILE *in = stdin;
 680         struct strbuf input = STRBUF_INIT, output = STRBUF_INIT;
 681         int ret;
 682         struct fmt_merge_msg_opts opts;
 683
 684         git_config(fmt_merge_msg_config, NULL);
 685         argc = parse_options(argc, argv, prefix, options, fmt_merge_msg_usage,
 686                              0);
 687         if (argc > 0)
 688                 usage_with_options(fmt_merge_msg_usage, options);
 689         if (shortlog_len < 0)
 690                 shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;
 691
 692         if (inpath && strcmp(inpath, "-")) {
 693                 in = fopen(inpath, "r");
 694                 if (!in)
 695                         die_errno("cannot open '%s'", inpath);
 696         }
 697
 698         if (strbuf_read(&input, fileno(in), 0) < 0)
 699                 die_errno("could not read input file");
 700
 701         if (message)
 702                 strbuf_addstr(&output, message);
 703
 704         memset(&opts, 0, sizeof(opts));
 705         opts.add_title = !message;
 706         opts.credit_people = 1;
 707         opts.shortlog_len = shortlog_len;
 708
 709         ret = fmt_merge_msg(&input, &output, &opts);
 710         if (ret)
 711                 return ret;
 712         write_in_full(STDOUT_FILENO, output.buf, output.len);
 713         return 0;
 714 }