builtin/log.c

   1 /*
   2  * Builtin "git log" and related commands (show, whatchanged)
   3  *
   4  * (C) Copyright 2006 Linus Torvalds
   5  *               2006 Junio Hamano
   6  */
   7 #include "cache.h"
   8 #include "color.h"
   9 #include "commit.h"
  10 #include "diff.h"
  11 #include "revision.h"
  12 #include "log-tree.h"
  13 #include "builtin.h"
  14 #include "tag.h"
  15 #include "reflog-walk.h"
  16 #include "patch-ids.h"
  17 #include "run-command.h"
  18 #include "shortlog.h"
  19 #include "remote.h"
  20 #include "string-list.h"
  21 #include "parse-options.h"
  22
  23 /* Set a default date-time format for git log ("log.date" config variable) */
  24 static const char *default_date_mode = NULL;
  25
  26 static int default_show_root = 1;
  27 static int decoration_style;
  28 static const char *fmt_patch_subject_prefix = "PATCH";
  29 static const char *fmt_pretty;
  30
  31 static const char * const builtin_log_usage =
  32         "git log [<options>] [<since>..<until>] [[--] <path>...]\n"
  33         "   or: git show [options] <object>...";
  34
  35 static int parse_decoration_style(const char *var, const char *value)
  36 {
  37         switch (git_config_maybe_bool(var, value)) {
  38         case 1:
  39                 return DECORATE_SHORT_REFS;
  40         case 0:
  41                 return 0;
  42         default:
  43                 break;
  44         }
  45         if (!strcmp(value, "full"))
  46                 return DECORATE_FULL_REFS;
  47         else if (!strcmp(value, "short"))
  48                 return DECORATE_SHORT_REFS;
  49         return -1;
  50 }
  51
  52 static void cmd_log_init(int argc, const char **argv, const char *prefix,
  53                          struct rev_info *rev, struct setup_revision_opt *opt)
  54 {
  55         int i;
  56         int decoration_given = 0;
  57         struct userformat_want w;
  58
  59         rev->abbrev = DEFAULT_ABBREV;
  60         rev->commit_format = CMIT_FMT_DEFAULT;
  61         if (fmt_pretty)
  62                 get_commit_format(fmt_pretty, rev);
  63         rev->verbose_header = 1;
  64         DIFF_OPT_SET(&rev->diffopt, RECURSIVE);
  65         rev->show_root_diff = default_show_root;
  66         rev->subject_prefix = fmt_patch_subject_prefix;
  67         DIFF_OPT_SET(&rev->diffopt, ALLOW_TEXTCONV);
  68
  69         if (default_date_mode)
  70                 rev->date_mode = parse_date_format(default_date_mode);
  71
  72         /*
  73          * Check for -h before setup_revisions(), or "git log -h" will
  74          * fail when run without a git directory.
  75          */
  76         if (argc == 2 && !strcmp(argv[1], "-h"))
  77                 usage(builtin_log_usage);
  78         argc = setup_revisions(argc, argv, rev, opt);
  79
  80         memset(&w, 0, sizeof(w));
  81         userformat_find_requirements(NULL, &w);
  82
  83         if (!rev->show_notes_given && (!rev->pretty_given || w.notes))
  84                 rev->show_notes = 1;
  85         if (rev->show_notes)
  86                 init_display_notes(&rev->notes_opt);
  87
  88         if (rev->diffopt.pickaxe || rev->diffopt.filter)
  89                 rev->always_show_header = 0;
  90         if (DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES)) {
  91                 rev->always_show_header = 0;
  92                 if (rev->diffopt.nr_paths != 1)
  93                         usage("git logs can only follow renames on one pathname at a time");
  94         }
  95         for (i = 1; i < argc; i++) {
  96                 const char *arg = argv[i];
  97                 if (!strcmp(arg, "--decorate")) {
  98                         decoration_style = DECORATE_SHORT_REFS;
  99                         decoration_given = 1;
 100                 } else if (!prefixcmp(arg, "--decorate=")) {
 101                         const char *v = skip_prefix(arg, "--decorate=");
 102                         decoration_style = parse_decoration_style(arg, v);
 103                         if (decoration_style < 0)
 104                                 die("invalid --decorate option: %s", arg);
 105                         decoration_given = 1;
 106                 } else if (!strcmp(arg, "--no-decorate")) {
 107                         decoration_style = 0;
 108                 } else if (!strcmp(arg, "--source")) {
 109                         rev->show_source = 1;
 110                 } else if (!strcmp(arg, "-h")) {
 111                         usage(builtin_log_usage);
 112                 } else
 113                         die("unrecognized argument: %s", arg);
 114         }
 115
 116         /*
 117          * defeat log.decorate configuration interacting with --pretty=raw
 118          * from the command line.
 119          */
 120         if (!decoration_given && rev->pretty_given
 121             && rev->commit_format == CMIT_FMT_RAW)
 122                 decoration_style = 0;
 123
 124         if (decoration_style) {
 125                 rev->show_decorations = 1;
 126                 load_ref_decorations(decoration_style);
 127         }
 128 }
 129
 130 /*
 131  * This gives a rough estimate for how many commits we
 132  * will print out in the list.
 133  */
 134 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
 135 {
 136         int n = 0;
 137
 138         while (list) {
 139                 struct commit *commit = list->item;
 140                 unsigned int flags = commit->object.flags;
 141                 list = list->next;
 142                 if (!(flags & (TREESAME | UNINTERESTING)))
 143                         n++;
 144         }
 145         return n;
 146 }
 147
 148 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
 149 {
 150         if (rev->shown_one) {
 151                 rev->shown_one = 0;
 152                 if (rev->commit_format != CMIT_FMT_ONELINE)
 153                         putchar(rev->diffopt.line_termination);
 154         }
 155         printf("Final output: %d %s\n", nr, stage);
 156 }
 157
 158 static struct itimerval early_output_timer;
 159
 160 static void log_show_early(struct rev_info *revs, struct commit_list *list)
 161 {
 162         int i = revs->early_output;
 163         int show_header = 1;
 164
 165         sort_in_topological_order(&list, revs->lifo);
 166         while (list && i) {
 167                 struct commit *commit = list->item;
 168                 switch (simplify_commit(revs, commit)) {
 169                 case commit_show:
 170                         if (show_header) {
 171                                 int n = estimate_commit_count(revs, list);
 172                                 show_early_header(revs, "incomplete", n);
 173                                 show_header = 0;
 174                         }
 175                         log_tree_commit(revs, commit);
 176                         i--;
 177                         break;
 178                 case commit_ignore:
 179                         break;
 180                 case commit_error:
 181                         return;
 182                 }
 183                 list = list->next;
 184         }
 185
 186         /* Did we already get enough commits for the early output? */
 187         if (!i)
 188                 return;
 189
 190         /*
 191          * ..if no, then repeat it twice a second until we
 192          * do.
 193          *
 194          * NOTE! We don't use "it_interval", because if the
 195          * reader isn't listening, we want our output to be
 196          * throttled by the writing, and not have the timer
 197          * trigger every second even if we're blocked on a
 198          * reader!
 199          */
 200         early_output_timer.it_value.tv_sec = 0;
 201         early_output_timer.it_value.tv_usec = 500000;
 202         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 203 }
 204
 205 static void early_output(int signal)
 206 {
 207         show_early_output = log_show_early;
 208 }
 209
 210 static void setup_early_output(struct rev_info *rev)
 211 {
 212         struct sigaction sa;
 213
 214         /*
 215          * Set up the signal handler, minimally intrusively:
 216          * we only set a single volatile integer word (not
 217          * using sigatomic_t - trying to avoid unnecessary
 218          * system dependencies and headers), and using
 219          * SA_RESTART.
 220          */
 221         memset(&sa, 0, sizeof(sa));
 222         sa.sa_handler = early_output;
 223         sigemptyset(&sa.sa_mask);
 224         sa.sa_flags = SA_RESTART;
 225         sigaction(SIGALRM, &sa, NULL);
 226
 227         /*
 228          * If we can get the whole output in less than a
 229          * tenth of a second, don't even bother doing the
 230          * early-output thing..
 231          *
 232          * This is a one-time-only trigger.
 233          */
 234         early_output_timer.it_value.tv_sec = 0;
 235         early_output_timer.it_value.tv_usec = 100000;
 236         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 237 }
 238
 239 static void finish_early_output(struct rev_info *rev)
 240 {
 241         int n = estimate_commit_count(rev, rev->commits);
 242         signal(SIGALRM, SIG_IGN);
 243         show_early_header(rev, "done", n);
 244 }
 245
 246 static int cmd_log_walk(struct rev_info *rev)
 247 {
 248         struct commit *commit;
 249
 250         if (rev->early_output)
 251                 setup_early_output(rev);
 252
 253         if (prepare_revision_walk(rev))
 254                 die("revision walk setup failed");
 255
 256         if (rev->early_output)
 257                 finish_early_output(rev);
 258
 259         /*
 260          * For --check and --exit-code, the exit code is based on CHECK_FAILED
 261          * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
 262          * retain that state information if replacing rev->diffopt in this loop
 263          */
 264         while ((commit = get_revision(rev)) != NULL) {
 265                 log_tree_commit(rev, commit);
 266                 if (!rev->reflog_info) {
 267                         /* we allow cycles in reflog ancestry */
 268                         free(commit->buffer);
 269                         commit->buffer = NULL;
 270                 }
 271                 free_commit_list(commit->parents);
 272                 commit->parents = NULL;
 273         }
 274         if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
 275             DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
 276                 return 02;
 277         }
 278         return diff_result_code(&rev->diffopt, 0);
 279 }
 280
 281 static int git_log_config(const char *var, const char *value, void *cb)
 282 {
 283         if (!strcmp(var, "format.pretty"))
 284                 return git_config_string(&fmt_pretty, var, value);
 285         if (!strcmp(var, "format.subjectprefix"))
 286                 return git_config_string(&fmt_patch_subject_prefix, var, value);
 287         if (!strcmp(var, "log.date"))
 288                 return git_config_string(&default_date_mode, var, value);
 289         if (!strcmp(var, "log.decorate")) {
 290                 decoration_style = parse_decoration_style(var, value);
 291                 if (decoration_style < 0)
 292                         decoration_style = 0; /* maybe warn? */
 293                 return 0;
 294         }
 295         if (!strcmp(var, "log.showroot")) {
 296                 default_show_root = git_config_bool(var, value);
 297                 return 0;
 298         }
 299         if (!prefixcmp(var, "color.decorate."))
 300                 return parse_decorate_color_config(var, 15, value);
 301
 302         return git_diff_ui_config(var, value, cb);
 303 }
 304
 305 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 306 {
 307         struct rev_info rev;
 308         struct setup_revision_opt opt;
 309
 310         git_config(git_log_config, NULL);
 311
 312         if (diff_use_color_default == -1)
 313                 diff_use_color_default = git_use_color_default;
 314
 315         init_revisions(&rev, prefix);
 316         rev.diff = 1;
 317         rev.simplify_history = 0;
 318         memset(&opt, 0, sizeof(opt));
 319         opt.def = "HEAD";
 320         cmd_log_init(argc, argv, prefix, &rev, &opt);
 321         if (!rev.diffopt.output_format)
 322                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
 323         return cmd_log_walk(&rev);
 324 }
 325
 326 static void show_tagger(char *buf, int len, struct rev_info *rev)
 327 {
 328         struct strbuf out = STRBUF_INIT;
 329
 330         pp_user_info("Tagger", rev->commit_format, &out, buf, rev->date_mode,
 331                 git_log_output_encoding ?
 332                 git_log_output_encoding: git_commit_encoding);
 333         printf("%s", out.buf);
 334         strbuf_release(&out);
 335 }
 336
 337 static int show_object(const unsigned char *sha1, int show_tag_object,
 338         struct rev_info *rev)
 339 {
 340         unsigned long size;
 341         enum object_type type;
 342         char *buf = read_sha1_file(sha1, &type, &size);
 343         int offset = 0;
 344
 345         if (!buf)
 346                 return error("Could not read object %s", sha1_to_hex(sha1));
 347
 348         if (show_tag_object)
 349                 while (offset < size && buf[offset] != '\n') {
 350                         int new_offset = offset + 1;
 351                         while (new_offset < size && buf[new_offset++] != '\n')
 352                                 ; /* do nothing */
 353                         if (!prefixcmp(buf + offset, "tagger "))
 354                                 show_tagger(buf + offset + 7,
 355                                             new_offset - offset - 7, rev);
 356                         offset = new_offset;
 357                 }
 358
 359         if (offset < size)
 360                 fwrite(buf + offset, size - offset, 1, stdout);
 361         free(buf);
 362         return 0;
 363 }
 364
 365 static int show_tree_object(const unsigned char *sha1,
 366                 const char *base, int baselen,
 367                 const char *pathname, unsigned mode, int stage, void *context)
 368 {
 369         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
 370         return 0;
 371 }
 372
 373 static void show_rev_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
 374 {
 375         if (rev->ignore_merges) {
 376                 /* There was no "-m" on the command line */
 377                 rev->ignore_merges = 0;
 378                 if (!rev->first_parent_only && !rev->combine_merges) {
 379                         /* No "--first-parent", "-c", nor "--cc" */
 380                         rev->combine_merges = 1;
 381                         rev->dense_combined_merges = 1;
 382                 }
 383         }
 384         if (!rev->diffopt.output_format)
 385                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
 386 }
 387
 388 int cmd_show(int argc, const char **argv, const char *prefix)
 389 {
 390         struct rev_info rev;
 391         struct object_array_entry *objects;
 392         struct setup_revision_opt opt;
 393         int i, count, ret = 0;
 394
 395         git_config(git_log_config, NULL);
 396
 397         if (diff_use_color_default == -1)
 398                 diff_use_color_default = git_use_color_default;
 399
 400         init_revisions(&rev, prefix);
 401         rev.diff = 1;
 402         rev.always_show_header = 1;
 403         rev.no_walk = 1;
 404         memset(&opt, 0, sizeof(opt));
 405         opt.def = "HEAD";
 406         opt.tweak = show_rev_tweak_rev;
 407         cmd_log_init(argc, argv, prefix, &rev, &opt);
 408
 409         count = rev.pending.nr;
 410         objects = rev.pending.objects;
 411         for (i = 0; i < count && !ret; i++) {
 412                 struct object *o = objects[i].item;
 413                 const char *name = objects[i].name;
 414                 switch (o->type) {
 415                 case OBJ_BLOB:
 416                         ret = show_object(o->sha1, 0, NULL);
 417                         break;
 418                 case OBJ_TAG: {
 419                         struct tag *t = (struct tag *)o;
 420
 421                         if (rev.shown_one)
 422                                 putchar('\n');
 423                         printf("%stag %s%s\n",
 424                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 425                                         t->tag,
 426                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 427                         ret = show_object(o->sha1, 1, &rev);
 428                         rev.shown_one = 1;
 429                         if (ret)
 430                                 break;
 431                         o = parse_object(t->tagged->sha1);
 432                         if (!o)
 433                                 ret = error("Could not read object %s",
 434                                             sha1_to_hex(t->tagged->sha1));
 435                         objects[i].item = o;
 436                         i--;
 437                         break;
 438                 }
 439                 case OBJ_TREE:
 440                         if (rev.shown_one)
 441                                 putchar('\n');
 442                         printf("%stree %s%s\n\n",
 443                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 444                                         name,
 445                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 446                         read_tree_recursive((struct tree *)o, "", 0, 0, NULL,
 447                                         show_tree_object, NULL);
 448                         rev.shown_one = 1;
 449                         break;
 450                 case OBJ_COMMIT:
 451                         rev.pending.nr = rev.pending.alloc = 0;
 452                         rev.pending.objects = NULL;
 453                         add_object_array(o, name, &rev.pending);
 454                         ret = cmd_log_walk(&rev);
 455                         break;
 456                 default:
 457                         ret = error("Unknown type: %d", o->type);
 458                 }
 459         }
 460         free(objects);
 461         return ret;
 462 }
 463
 464 /*
 465  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
 466  */
 467 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
 468 {
 469         struct rev_info rev;
 470         struct setup_revision_opt opt;
 471
 472         git_config(git_log_config, NULL);
 473
 474         if (diff_use_color_default == -1)
 475                 diff_use_color_default = git_use_color_default;
 476
 477         init_revisions(&rev, prefix);
 478         init_reflog_walk(&rev.reflog_info);
 479         rev.abbrev_commit = 1;
 480         rev.verbose_header = 1;
 481         memset(&opt, 0, sizeof(opt));
 482         opt.def = "HEAD";
 483         cmd_log_init(argc, argv, prefix, &rev, &opt);
 484
 485         /*
 486          * This means that we override whatever commit format the user gave
 487          * on the cmd line.  Sad, but cmd_log_init() currently doesn't
 488          * allow us to set a different default.
 489          */
 490         rev.commit_format = CMIT_FMT_ONELINE;
 491         rev.use_terminator = 1;
 492         rev.always_show_header = 1;
 493
 494         /*
 495          * We get called through "git reflog", so unlike the other log
 496          * routines, we need to set up our pager manually..
 497          */
 498         setup_pager();
 499
 500         return cmd_log_walk(&rev);
 501 }
 502
 503 int cmd_log(int argc, const char **argv, const char *prefix)
 504 {
 505         struct rev_info rev;
 506         struct setup_revision_opt opt;
 507
 508         git_config(git_log_config, NULL);
 509
 510         if (diff_use_color_default == -1)
 511                 diff_use_color_default = git_use_color_default;
 512
 513         init_revisions(&rev, prefix);
 514         rev.always_show_header = 1;
 515         memset(&opt, 0, sizeof(opt));
 516         opt.def = "HEAD";
 517         cmd_log_init(argc, argv, prefix, &rev, &opt);
 518         return cmd_log_walk(&rev);
 519 }
 520
 521 /* format-patch */
 522
 523 static const char *fmt_patch_suffix = ".patch";
 524 static int numbered = 0;
 525 static int auto_number = 1;
 526
 527 static char *default_attach = NULL;
 528
 529 static struct string_list extra_hdr;
 530 static struct string_list extra_to;
 531 static struct string_list extra_cc;
 532
 533 static void add_header(const char *value)
 534 {
 535         struct string_list_item *item;
 536         int len = strlen(value);
 537         while (len && value[len - 1] == '\n')
 538                 len--;
 539
 540         if (!strncasecmp(value, "to: ", 4)) {
 541                 item = string_list_append(&extra_to, value + 4);
 542                 len -= 4;
 543         } else if (!strncasecmp(value, "cc: ", 4)) {
 544                 item = string_list_append(&extra_cc, value + 4);
 545                 len -= 4;
 546         } else {
 547                 item = string_list_append(&extra_hdr, value);
 548         }
 549
 550         item->string[len] = '\0';
 551 }
 552
 553 #define THREAD_SHALLOW 1
 554 #define THREAD_DEEP 2
 555 static int thread;
 556 static int do_signoff;
 557 static const char *signature = git_version_string;
 558
 559 static int git_format_config(const char *var, const char *value, void *cb)
 560 {
 561         if (!strcmp(var, "format.headers")) {
 562                 if (!value)
 563                         die("format.headers without value");
 564                 add_header(value);
 565                 return 0;
 566         }
 567         if (!strcmp(var, "format.suffix"))
 568                 return git_config_string(&fmt_patch_suffix, var, value);
 569         if (!strcmp(var, "format.to")) {
 570                 if (!value)
 571                         return config_error_nonbool(var);
 572                 string_list_append(&extra_to, value);
 573                 return 0;
 574         }
 575         if (!strcmp(var, "format.cc")) {
 576                 if (!value)
 577                         return config_error_nonbool(var);
 578                 string_list_append(&extra_cc, value);
 579                 return 0;
 580         }
 581         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
 582                 return 0;
 583         }
 584         if (!strcmp(var, "format.numbered")) {
 585                 if (value && !strcasecmp(value, "auto")) {
 586                         auto_number = 1;
 587                         return 0;
 588                 }
 589                 numbered = git_config_bool(var, value);
 590                 auto_number = auto_number && numbered;
 591                 return 0;
 592         }
 593         if (!strcmp(var, "format.attach")) {
 594                 if (value && *value)
 595                         default_attach = xstrdup(value);
 596                 else
 597                         default_attach = xstrdup(git_version_string);
 598                 return 0;
 599         }
 600         if (!strcmp(var, "format.thread")) {
 601                 if (value && !strcasecmp(value, "deep")) {
 602                         thread = THREAD_DEEP;
 603                         return 0;
 604                 }
 605                 if (value && !strcasecmp(value, "shallow")) {
 606                         thread = THREAD_SHALLOW;
 607                         return 0;
 608                 }
 609                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
 610                 return 0;
 611         }
 612         if (!strcmp(var, "format.signoff")) {
 613                 do_signoff = git_config_bool(var, value);
 614                 return 0;
 615         }
 616         if (!strcmp(var, "format.signature"))
 617                 return git_config_string(&signature, var, value);
 618
 619         return git_log_config(var, value, cb);
 620 }
 621
 622 static FILE *realstdout = NULL;
 623 static const char *output_directory = NULL;
 624 static int outdir_offset;
 625
 626 static int reopen_stdout(struct commit *commit, struct rev_info *rev)
 627 {
 628         struct strbuf filename = STRBUF_INIT;
 629         int suffix_len = strlen(fmt_patch_suffix) + 1;
 630
 631         if (output_directory) {
 632                 strbuf_addstr(&filename, output_directory);
 633                 if (filename.len >=
 634                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
 635                         return error("name of output directory is too long");
 636                 if (filename.buf[filename.len - 1] != '/')
 637                         strbuf_addch(&filename, '/');
 638         }
 639
 640         get_patch_filename(commit, rev->nr, fmt_patch_suffix, &filename);
 641
 642         if (!DIFF_OPT_TST(&rev->diffopt, QUICK))
 643                 fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
 644
 645         if (freopen(filename.buf, "w", stdout) == NULL)
 646                 return error("Cannot open patch file %s", filename.buf);
 647
 648         strbuf_release(&filename);
 649         return 0;
 650 }
 651
 652 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids, const char *prefix)
 653 {
 654         struct rev_info check_rev;
 655         struct commit *commit;
 656         struct object *o1, *o2;
 657         unsigned flags1, flags2;
 658
 659         if (rev->pending.nr != 2)
 660                 die("Need exactly one range.");
 661
 662         o1 = rev->pending.objects[0].item;
 663         flags1 = o1->flags;
 664         o2 = rev->pending.objects[1].item;
 665         flags2 = o2->flags;
 666
 667         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
 668                 die("Not a range.");
 669
 670         init_patch_ids(ids);
 671
 672         /* given a range a..b get all patch ids for b..a */
 673         init_revisions(&check_rev, prefix);
 674         o1->flags ^= UNINTERESTING;
 675         o2->flags ^= UNINTERESTING;
 676         add_pending_object(&check_rev, o1, "o1");
 677         add_pending_object(&check_rev, o2, "o2");
 678         if (prepare_revision_walk(&check_rev))
 679                 die("revision walk setup failed");
 680
 681         while ((commit = get_revision(&check_rev)) != NULL) {
 682                 /* ignore merges */
 683                 if (commit->parents && commit->parents->next)
 684                         continue;
 685
 686                 add_commit_patch_id(commit, ids);
 687         }
 688
 689         /* reset for next revision walk */
 690         clear_commit_marks((struct commit *)o1,
 691                         SEEN | UNINTERESTING | SHOWN | ADDED);
 692         clear_commit_marks((struct commit *)o2,
 693                         SEEN | UNINTERESTING | SHOWN | ADDED);
 694         o1->flags = flags1;
 695         o2->flags = flags2;
 696 }
 697
 698 static void gen_message_id(struct rev_info *info, char *base)
 699 {
 700         const char *committer = git_committer_info(IDENT_WARN_ON_NO_NAME);
 701         const char *email_start = strrchr(committer, '<');
 702         const char *email_end = strrchr(committer, '>');
 703         struct strbuf buf = STRBUF_INIT;
 704         if (!email_start || !email_end || email_start > email_end - 1)
 705                 die("Could not extract email from committer identity.");
 706         strbuf_addf(&buf, "%s.%lu.git.%.*s", base,
 707                     (unsigned long) time(NULL),
 708                     (int)(email_end - email_start - 1), email_start + 1);
 709         info->message_id = strbuf_detach(&buf, NULL);
 710 }
 711
 712 static void print_signature(void)
 713 {
 714         if (signature && *signature)
 715                 printf("-- \n%s\n\n", signature);
 716 }
 717
 718 static void make_cover_letter(struct rev_info *rev, int use_stdout,
 719                               int numbered, int numbered_files,
 720                               struct commit *origin,
 721                               int nr, struct commit **list, struct commit *head)
 722 {
 723         const char *committer;
 724         const char *subject_start = NULL;
 725         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
 726         const char *msg;
 727         const char *extra_headers = rev->extra_headers;
 728         struct shortlog log;
 729         struct strbuf sb = STRBUF_INIT;
 730         int i;
 731         const char *encoding = "UTF-8";
 732         struct diff_options opts;
 733         int need_8bit_cte = 0;
 734         struct commit *commit = NULL;
 735
 736         if (rev->commit_format != CMIT_FMT_EMAIL)
 737                 die("Cover letter needs email format");
 738
 739         committer = git_committer_info(0);
 740
 741         if (!numbered_files) {
 742                 /*
 743                  * We fake a commit for the cover letter so we get the filename
 744                  * desired.
 745                  */
 746                 commit = xcalloc(1, sizeof(*commit));
 747                 commit->buffer = xmalloc(400);
 748                 snprintf(commit->buffer, 400,
 749                         "tree 0000000000000000000000000000000000000000\n"
 750                         "parent %s\n"
 751                         "author %s\n"
 752                         "committer %s\n\n"
 753                         "cover letter\n",
 754                         sha1_to_hex(head->object.sha1), committer, committer);
 755         }
 756
 757         if (!use_stdout && reopen_stdout(commit, rev))
 758                 return;
 759
 760         if (commit) {
 761
 762                 free(commit->buffer);
 763                 free(commit);
 764         }
 765
 766         log_write_email_headers(rev, head, &subject_start, &extra_headers,
 767                                 &need_8bit_cte);
 768
 769         for (i = 0; !need_8bit_cte && i < nr; i++)
 770                 if (has_non_ascii(list[i]->buffer))
 771                         need_8bit_cte = 1;
 772
 773         msg = body;
 774         pp_user_info(NULL, CMIT_FMT_EMAIL, &sb, committer, DATE_RFC2822,
 775                      encoding);
 776         pp_title_line(CMIT_FMT_EMAIL, &msg, &sb, subject_start, extra_headers,
 777                       encoding, need_8bit_cte);
 778         pp_remainder(CMIT_FMT_EMAIL, &msg, &sb, 0);
 779         printf("%s\n", sb.buf);
 780
 781         strbuf_release(&sb);
 782
 783         shortlog_init(&log);
 784         log.wrap_lines = 1;
 785         log.wrap = 72;
 786         log.in1 = 2;
 787         log.in2 = 4;
 788         for (i = 0; i < nr; i++)
 789                 shortlog_add_commit(&log, list[i]);
 790
 791         shortlog_output(&log);
 792
 793         /*
 794          * We can only do diffstat with a unique reference point
 795          */
 796         if (!origin)
 797                 return;
 798
 799         memcpy(&opts, &rev->diffopt, sizeof(opts));
 800         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
 801
 802         diff_setup_done(&opts);
 803
 804         diff_tree_sha1(origin->tree->object.sha1,
 805                        head->tree->object.sha1,
 806                        "", &opts);
 807         diffcore_std(&opts);
 808         diff_flush(&opts);
 809
 810         printf("\n");
 811         print_signature();
 812 }
 813
 814 static const char *clean_message_id(const char *msg_id)
 815 {
 816         char ch;
 817         const char *a, *z, *m;
 818
 819         m = msg_id;
 820         while ((ch = *m) && (isspace(ch) || (ch == '<')))
 821                 m++;
 822         a = m;
 823         z = NULL;
 824         while ((ch = *m)) {
 825                 if (!isspace(ch) && (ch != '>'))
 826                         z = m;
 827                 m++;
 828         }
 829         if (!z)
 830                 die("insane in-reply-to: %s", msg_id);
 831         if (++z == m)
 832                 return a;
 833         return xmemdupz(a, z - a);
 834 }
 835
 836 static const char *set_outdir(const char *prefix, const char *output_directory)
 837 {
 838         if (output_directory && is_absolute_path(output_directory))
 839                 return output_directory;
 840
 841         if (!prefix || !*prefix) {
 842                 if (output_directory)
 843                         return output_directory;
 844                 /* The user did not explicitly ask for "./" */
 845                 outdir_offset = 2;
 846                 return "./";
 847         }
 848
 849         outdir_offset = strlen(prefix);
 850         if (!output_directory)
 851                 return prefix;
 852
 853         return xstrdup(prefix_filename(prefix, outdir_offset,
 854                                        output_directory));
 855 }
 856
 857 static const char * const builtin_format_patch_usage[] = {
 858         "git format-patch [options] [<since> | <revision range>]",
 859         NULL
 860 };
 861
 862 static int keep_subject = 0;
 863
 864 static int keep_callback(const struct option *opt, const char *arg, int unset)
 865 {
 866         ((struct rev_info *)opt->value)->total = -1;
 867         keep_subject = 1;
 868         return 0;
 869 }
 870
 871 static int subject_prefix = 0;
 872
 873 static int subject_prefix_callback(const struct option *opt, const char *arg,
 874                             int unset)
 875 {
 876         subject_prefix = 1;
 877         ((struct rev_info *)opt->value)->subject_prefix = arg;
 878         return 0;
 879 }
 880
 881 static int numbered_cmdline_opt = 0;
 882
 883 static int numbered_callback(const struct option *opt, const char *arg,
 884                              int unset)
 885 {
 886         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
 887         if (unset)
 888                 auto_number =  0;
 889         return 0;
 890 }
 891
 892 static int no_numbered_callback(const struct option *opt, const char *arg,
 893                                 int unset)
 894 {
 895         return numbered_callback(opt, arg, 1);
 896 }
 897
 898 static int output_directory_callback(const struct option *opt, const char *arg,
 899                               int unset)
 900 {
 901         const char **dir = (const char **)opt->value;
 902         if (*dir)
 903                 die("Two output directories?");
 904         *dir = arg;
 905         return 0;
 906 }
 907
 908 static int thread_callback(const struct option *opt, const char *arg, int unset)
 909 {
 910         int *thread = (int *)opt->value;
 911         if (unset)
 912                 *thread = 0;
 913         else if (!arg || !strcmp(arg, "shallow"))
 914                 *thread = THREAD_SHALLOW;
 915         else if (!strcmp(arg, "deep"))
 916                 *thread = THREAD_DEEP;
 917         else
 918                 return 1;
 919         return 0;
 920 }
 921
 922 static int attach_callback(const struct option *opt, const char *arg, int unset)
 923 {
 924         struct rev_info *rev = (struct rev_info *)opt->value;
 925         if (unset)
 926                 rev->mime_boundary = NULL;
 927         else if (arg)
 928                 rev->mime_boundary = arg;
 929         else
 930                 rev->mime_boundary = git_version_string;
 931         rev->no_inline = unset ? 0 : 1;
 932         return 0;
 933 }
 934
 935 static int inline_callback(const struct option *opt, const char *arg, int unset)
 936 {
 937         struct rev_info *rev = (struct rev_info *)opt->value;
 938         if (unset)
 939                 rev->mime_boundary = NULL;
 940         else if (arg)
 941                 rev->mime_boundary = arg;
 942         else
 943                 rev->mime_boundary = git_version_string;
 944         rev->no_inline = 0;
 945         return 0;
 946 }
 947
 948 static int header_callback(const struct option *opt, const char *arg, int unset)
 949 {
 950         if (unset) {
 951                 string_list_clear(&extra_hdr, 0);
 952                 string_list_clear(&extra_to, 0);
 953                 string_list_clear(&extra_cc, 0);
 954         } else {
 955             add_header(arg);
 956         }
 957         return 0;
 958 }
 959
 960 static int to_callback(const struct option *opt, const char *arg, int unset)
 961 {
 962         if (unset)
 963                 string_list_clear(&extra_to, 0);
 964         else
 965                 string_list_append(&extra_to, arg);
 966         return 0;
 967 }
 968
 969 static int cc_callback(const struct option *opt, const char *arg, int unset)
 970 {
 971         if (unset)
 972                 string_list_clear(&extra_cc, 0);
 973         else
 974                 string_list_append(&extra_cc, arg);
 975         return 0;
 976 }
 977
 978 int cmd_format_patch(int argc, const char **argv, const char *prefix)
 979 {
 980         struct commit *commit;
 981         struct commit **list = NULL;
 982         struct rev_info rev;
 983         struct setup_revision_opt s_r_opt;
 984         int nr = 0, total, i;
 985         int use_stdout = 0;
 986         int start_number = -1;
 987         int numbered_files = 0;         /* _just_ numbers */
 988         int ignore_if_in_upstream = 0;
 989         int cover_letter = 0;
 990         int boundary_count = 0;
 991         int no_binary_diff = 0;
 992         struct commit *origin = NULL, *head = NULL;
 993         const char *in_reply_to = NULL;
 994         struct patch_ids ids;
 995         char *add_signoff = NULL;
 996         struct strbuf buf = STRBUF_INIT;
 997         int use_patch_format = 0;
 998         const struct option builtin_format_patch_options[] = {
 999                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
1000                             "use [PATCH n/m] even with a single patch",
1001                             PARSE_OPT_NOARG, numbered_callback },
1002                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
1003                             "use [PATCH] even with multiple patches",
1004                             PARSE_OPT_NOARG, no_numbered_callback },
1005                 OPT_BOOLEAN('s', "signoff", &do_signoff, "add Signed-off-by:"),
1006                 OPT_BOOLEAN(0, "stdout", &use_stdout,
1007                             "print patches to standard out"),
1008                 OPT_BOOLEAN(0, "cover-letter", &cover_letter,
1009                             "generate a cover letter"),
1010                 OPT_BOOLEAN(0, "numbered-files", &numbered_files,
1011                             "use simple number sequence for output file names"),
1012                 OPT_STRING(0, "suffix", &fmt_patch_suffix, "sfx",
1013                             "use <sfx> instead of '.patch'"),
1014                 OPT_INTEGER(0, "start-number", &start_number,
1015                             "start numbering patches at <n> instead of 1"),
1016                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, "prefix",
1017                             "Use [<prefix>] instead of [PATCH]",
1018                             PARSE_OPT_NONEG, subject_prefix_callback },
1019                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
1020                             "dir", "store resulting files in <dir>",
1021                             PARSE_OPT_NONEG, output_directory_callback },
1022                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
1023                             "don't strip/add [PATCH]",
1024                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
1025                 OPT_BOOLEAN(0, "no-binary", &no_binary_diff,
1026                             "don't output binary diffs"),
1027                 OPT_BOOLEAN(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
1028                             "don't include a patch matching a commit upstream"),
1029                 { OPTION_BOOLEAN, 'p', "no-stat", &use_patch_format, NULL,
1030                   "show patch format instead of default (patch + stat)",
1031                   PARSE_OPT_NONEG | PARSE_OPT_NOARG },
1032                 OPT_GROUP("Messaging"),
1033                 { OPTION_CALLBACK, 0, "add-header", NULL, "header",
1034                             "add email header", 0, header_callback },
1035                 { OPTION_CALLBACK, 0, "to", NULL, "email", "add To: header",
1036                             0, to_callback },
1037                 { OPTION_CALLBACK, 0, "cc", NULL, "email", "add Cc: header",
1038                             0, cc_callback },
1039                 OPT_STRING(0, "in-reply-to", &in_reply_to, "message-id",
1040                             "make first mail a reply to <message-id>"),
1041                 { OPTION_CALLBACK, 0, "attach", &rev, "boundary",
1042                             "attach the patch", PARSE_OPT_OPTARG,
1043                             attach_callback },
1044                 { OPTION_CALLBACK, 0, "inline", &rev, "boundary",
1045                             "inline the patch",
1046                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
1047                             inline_callback },
1048                 { OPTION_CALLBACK, 0, "thread", &thread, "style",
1049                             "enable message threading, styles: shallow, deep",
1050                             PARSE_OPT_OPTARG, thread_callback },
1051                 OPT_STRING(0, "signature", &signature, "signature",
1052                             "add a signature"),
1053                 OPT_END()
1054         };
1055
1056         extra_hdr.strdup_strings = 1;
1057         extra_to.strdup_strings = 1;
1058         extra_cc.strdup_strings = 1;
1059         git_config(git_format_config, NULL);
1060         init_revisions(&rev, prefix);
1061         rev.commit_format = CMIT_FMT_EMAIL;
1062         rev.verbose_header = 1;
1063         rev.diff = 1;
1064         rev.combine_merges = 0;
1065         rev.ignore_merges = 1;
1066         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
1067         rev.subject_prefix = fmt_patch_subject_prefix;
1068         memset(&s_r_opt, 0, sizeof(s_r_opt));
1069         s_r_opt.def = "HEAD";
1070
1071         if (default_attach) {
1072                 rev.mime_boundary = default_attach;
1073                 rev.no_inline = 1;
1074         }
1075
1076         /*
1077          * Parse the arguments before setup_revisions(), or something
1078          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1079          * possibly a valid SHA1.
1080          */
1081         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1082                              builtin_format_patch_usage,
1083                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1084                              PARSE_OPT_KEEP_DASHDASH);
1085
1086         if (do_signoff) {
1087                 const char *committer;
1088                 const char *endpos;
1089                 committer = git_committer_info(IDENT_ERROR_ON_NO_NAME);
1090                 endpos = strchr(committer, '>');
1091                 if (!endpos)
1092                         die("bogus committer info %s", committer);
1093                 add_signoff = xmemdupz(committer, endpos - committer + 1);
1094         }
1095
1096         for (i = 0; i < extra_hdr.nr; i++) {
1097                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1098                 strbuf_addch(&buf, '\n');
1099         }
1100
1101         if (extra_to.nr)
1102                 strbuf_addstr(&buf, "To: ");
1103         for (i = 0; i < extra_to.nr; i++) {
1104                 if (i)
1105                         strbuf_addstr(&buf, "    ");
1106                 strbuf_addstr(&buf, extra_to.items[i].string);
1107                 if (i + 1 < extra_to.nr)
1108                         strbuf_addch(&buf, ',');
1109                 strbuf_addch(&buf, '\n');
1110         }
1111
1112         if (extra_cc.nr)
1113                 strbuf_addstr(&buf, "Cc: ");
1114         for (i = 0; i < extra_cc.nr; i++) {
1115                 if (i)
1116                         strbuf_addstr(&buf, "    ");
1117                 strbuf_addstr(&buf, extra_cc.items[i].string);
1118                 if (i + 1 < extra_cc.nr)
1119                         strbuf_addch(&buf, ',');
1120                 strbuf_addch(&buf, '\n');
1121         }
1122
1123         rev.extra_headers = strbuf_detach(&buf, NULL);
1124
1125         if (start_number < 0)
1126                 start_number = 1;
1127
1128         /*
1129          * If numbered is set solely due to format.numbered in config,
1130          * and it would conflict with --keep-subject (-k) from the
1131          * command line, reset "numbered".
1132          */
1133         if (numbered && keep_subject && !numbered_cmdline_opt)
1134                 numbered = 0;
1135
1136         if (numbered && keep_subject)
1137                 die ("-n and -k are mutually exclusive.");
1138         if (keep_subject && subject_prefix)
1139                 die ("--subject-prefix and -k are mutually exclusive.");
1140
1141         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1142         if (argc > 1)
1143                 die ("unrecognized argument: %s", argv[1]);
1144
1145         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1146                 die("--name-only does not make sense");
1147         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1148                 die("--name-status does not make sense");
1149         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1150                 die("--check does not make sense");
1151
1152         if (!use_patch_format &&
1153                 (!rev.diffopt.output_format ||
1154                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1155                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1156
1157         /* Always generate a patch */
1158         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1159
1160         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1161                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1162
1163         if (rev.show_notes)
1164                 init_display_notes(&rev.notes_opt);
1165
1166         if (!use_stdout)
1167                 output_directory = set_outdir(prefix, output_directory);
1168
1169         if (output_directory) {
1170                 if (use_stdout)
1171                         die("standard output, or directory, which one?");
1172                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1173                         die_errno("Could not create directory '%s'",
1174                                   output_directory);
1175         }
1176
1177         if (rev.pending.nr == 1) {
1178                 if (rev.max_count < 0 && !rev.show_root_diff) {
1179                         /*
1180                          * This is traditional behaviour of "git format-patch
1181                          * origin" that prepares what the origin side still
1182                          * does not have.
1183                          */
1184                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1185                         add_head_to_pending(&rev);
1186                 }
1187                 /*
1188                  * Otherwise, it is "format-patch -22 HEAD", and/or
1189                  * "format-patch --root HEAD".  The user wants
1190                  * get_revision() to do the usual traversal.
1191                  */
1192         }
1193
1194         /*
1195          * We cannot move this anywhere earlier because we do want to
1196          * know if --root was given explicitly from the command line.
1197          */
1198         rev.show_root_diff = 1;
1199
1200         if (cover_letter) {
1201                 /* remember the range */
1202                 int i;
1203                 for (i = 0; i < rev.pending.nr; i++) {
1204                         struct object *o = rev.pending.objects[i].item;
1205                         if (!(o->flags & UNINTERESTING))
1206                                 head = (struct commit *)o;
1207                 }
1208                 /* We can't generate a cover letter without any patches */
1209                 if (!head)
1210                         return 0;
1211         }
1212
1213         if (ignore_if_in_upstream) {
1214                 /* Don't say anything if head and upstream are the same. */
1215                 if (rev.pending.nr == 2) {
1216                         struct object_array_entry *o = rev.pending.objects;
1217                         if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1218                                 return 0;
1219                 }
1220                 get_patch_ids(&rev, &ids, prefix);
1221         }
1222
1223         if (!use_stdout)
1224                 realstdout = xfdopen(xdup(1), "w");
1225
1226         if (prepare_revision_walk(&rev))
1227                 die("revision walk setup failed");
1228         rev.boundary = 1;
1229         while ((commit = get_revision(&rev)) != NULL) {
1230                 if (commit->object.flags & BOUNDARY) {
1231                         boundary_count++;
1232                         origin = (boundary_count == 1) ? commit : NULL;
1233                         continue;
1234                 }
1235
1236                 /* ignore merges */
1237                 if (commit->parents && commit->parents->next)
1238                         continue;
1239
1240                 if (ignore_if_in_upstream &&
1241                                 has_commit_patch_id(commit, &ids))
1242                         continue;
1243
1244                 nr++;
1245                 list = xrealloc(list, nr * sizeof(list[0]));
1246                 list[nr - 1] = commit;
1247         }
1248         total = nr;
1249         if (!keep_subject && auto_number && total > 1)
1250                 numbered = 1;
1251         if (numbered)
1252                 rev.total = total + start_number - 1;
1253         if (in_reply_to || thread || cover_letter)
1254                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1255         if (in_reply_to) {
1256                 const char *msgid = clean_message_id(in_reply_to);
1257                 string_list_append(rev.ref_message_ids, msgid);
1258         }
1259         rev.numbered_files = numbered_files;
1260         rev.patch_suffix = fmt_patch_suffix;
1261         if (cover_letter) {
1262                 if (thread)
1263                         gen_message_id(&rev, "cover");
1264                 make_cover_letter(&rev, use_stdout, numbered, numbered_files,
1265                                   origin, nr, list, head);
1266                 total++;
1267                 start_number--;
1268         }
1269         rev.add_signoff = add_signoff;
1270         while (0 <= --nr) {
1271                 int shown;
1272                 commit = list[nr];
1273                 rev.nr = total - nr + (start_number - 1);
1274                 /* Make the second and subsequent mails replies to the first */
1275                 if (thread) {
1276                         /* Have we already had a message ID? */
1277                         if (rev.message_id) {
1278                                 /*
1279                                  * For deep threading: make every mail
1280                                  * a reply to the previous one, no
1281                                  * matter what other options are set.
1282                                  *
1283                                  * For shallow threading:
1284                                  *
1285                                  * Without --cover-letter and
1286                                  * --in-reply-to, make every mail a
1287                                  * reply to the one before.
1288                                  *
1289                                  * With --in-reply-to but no
1290                                  * --cover-letter, make every mail a
1291                                  * reply to the <reply-to>.
1292                                  *
1293                                  * With --cover-letter, make every
1294                                  * mail but the cover letter a reply
1295                                  * to the cover letter.  The cover
1296                                  * letter is a reply to the
1297                                  * --in-reply-to, if specified.
1298                                  */
1299                                 if (thread == THREAD_SHALLOW
1300                                     && rev.ref_message_ids->nr > 0
1301                                     && (!cover_letter || rev.nr > 1))
1302                                         free(rev.message_id);
1303                                 else
1304                                         string_list_append(rev.ref_message_ids,
1305                                                            rev.message_id);
1306                         }
1307                         gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
1308                 }
1309
1310                 if (!use_stdout && reopen_stdout(numbered_files ? NULL : commit,
1311                                                  &rev))
1312                         die("Failed to create output files");
1313                 shown = log_tree_commit(&rev, commit);
1314                 free(commit->buffer);
1315                 commit->buffer = NULL;
1316
1317                 /* We put one extra blank line between formatted
1318                  * patches and this flag is used by log-tree code
1319                  * to see if it needs to emit a LF before showing
1320                  * the log; when using one file per patch, we do
1321                  * not want the extra blank line.
1322                  */
1323                 if (!use_stdout)
1324                         rev.shown_one = 0;
1325                 if (shown) {
1326                         if (rev.mime_boundary)
1327                                 printf("\n--%s%s--\n\n\n",
1328                                        mime_boundary_leader,
1329                                        rev.mime_boundary);
1330                         else
1331                                 print_signature();
1332                 }
1333                 if (!use_stdout)
1334                         fclose(stdout);
1335         }
1336         free(list);
1337         string_list_clear(&extra_to, 0);
1338         string_list_clear(&extra_cc, 0);
1339         string_list_clear(&extra_hdr, 0);
1340         if (ignore_if_in_upstream)
1341                 free_patch_ids(&ids);
1342         return 0;
1343 }
1344
1345 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1346 {
1347         unsigned char sha1[20];
1348         if (get_sha1(arg, sha1) == 0) {
1349                 struct commit *commit = lookup_commit_reference(sha1);
1350                 if (commit) {
1351                         commit->object.flags |= flags;
1352                         add_pending_object(revs, &commit->object, arg);
1353                         return 0;
1354                 }
1355         }
1356         return -1;
1357 }
1358
1359 static const char * const cherry_usage[] = {
1360         "git cherry [-v] [<upstream> [<head> [<limit>]]]",
1361         NULL
1362 };
1363
1364 int cmd_cherry(int argc, const char **argv, const char *prefix)
1365 {
1366         struct rev_info revs;
1367         struct patch_ids ids;
1368         struct commit *commit;
1369         struct commit_list *list = NULL;
1370         struct branch *current_branch;
1371         const char *upstream;
1372         const char *head = "HEAD";
1373         const char *limit = NULL;
1374         int verbose = 0, abbrev = 0;
1375
1376         struct option options[] = {
1377                 OPT__ABBREV(&abbrev),
1378                 OPT__VERBOSE(&verbose),
1379                 OPT_END()
1380         };
1381
1382         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
1383
1384         switch (argc) {
1385         case 3:
1386                 limit = argv[2];
1387                 /* FALLTHROUGH */
1388         case 2:
1389                 head = argv[1];
1390                 /* FALLTHROUGH */
1391         case 1:
1392                 upstream = argv[0];
1393                 break;
1394         default:
1395                 current_branch = branch_get(NULL);
1396                 if (!current_branch || !current_branch->merge
1397                                         || !current_branch->merge[0]
1398                                         || !current_branch->merge[0]->dst) {
1399                         fprintf(stderr, "Could not find a tracked"
1400                                         " remote branch, please"
1401                                         " specify <upstream> manually.\n");
1402                         usage_with_options(cherry_usage, options);
1403                 }
1404
1405                 upstream = current_branch->merge[0]->dst;
1406         }
1407
1408         init_revisions(&revs, prefix);
1409         revs.diff = 1;
1410         revs.combine_merges = 0;
1411         revs.ignore_merges = 1;
1412         DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
1413
1414         if (add_pending_commit(head, &revs, 0))
1415                 die("Unknown commit %s", head);
1416         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1417                 die("Unknown commit %s", upstream);
1418
1419         /* Don't say anything if head and upstream are the same. */
1420         if (revs.pending.nr == 2) {
1421                 struct object_array_entry *o = revs.pending.objects;
1422                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1423                         return 0;
1424         }
1425
1426         get_patch_ids(&revs, &ids, prefix);
1427
1428         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1429                 die("Unknown commit %s", limit);
1430
1431         /* reverse the list of commits */
1432         if (prepare_revision_walk(&revs))
1433                 die("revision walk setup failed");
1434         while ((commit = get_revision(&revs)) != NULL) {
1435                 /* ignore merges */
1436                 if (commit->parents && commit->parents->next)
1437                         continue;
1438
1439                 commit_list_insert(commit, &list);
1440         }
1441
1442         while (list) {
1443                 char sign = '+';
1444
1445                 commit = list->item;
1446                 if (has_commit_patch_id(commit, &ids))
1447                         sign = '-';
1448
1449                 if (verbose) {
1450                         struct strbuf buf = STRBUF_INIT;
1451                         struct pretty_print_context ctx = {0};
1452                         pretty_print_commit(CMIT_FMT_ONELINE, commit,
1453                                             &buf, &ctx);
1454                         printf("%c %s %s\n", sign,
1455                                find_unique_abbrev(commit->object.sha1, abbrev),
1456                                buf.buf);
1457                         strbuf_release(&buf);
1458                 }
1459                 else {
1460                         printf("%c %s\n", sign,
1461                                find_unique_abbrev(commit->object.sha1, abbrev));
1462                 }
1463
1464                 list = list->next;
1465         }
1466
1467         free_patch_ids(&ids);
1468         return 0;
1469 }