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_defaults(struct rev_info *rev)
  53 {
  54         rev->abbrev = DEFAULT_ABBREV;
  55         rev->commit_format = CMIT_FMT_DEFAULT;
  56         if (fmt_pretty)
  57                 get_commit_format(fmt_pretty, rev);
  58         rev->verbose_header = 1;
  59         DIFF_OPT_SET(&rev->diffopt, RECURSIVE);
  60         rev->show_root_diff = default_show_root;
  61         rev->subject_prefix = fmt_patch_subject_prefix;
  62         DIFF_OPT_SET(&rev->diffopt, ALLOW_TEXTCONV);
  63
  64         if (default_date_mode)
  65                 rev->date_mode = parse_date_format(default_date_mode);
  66 }
  67
  68 static void cmd_log_init_finish(int argc, const char **argv, const char *prefix,
  69                          struct rev_info *rev, struct setup_revision_opt *opt)
  70 {
  71         int i;
  72         int decoration_given = 0;
  73         struct userformat_want w;
  74         /*
  75          * Check for -h before setup_revisions(), or "git log -h" will
  76          * fail when run without a git directory.
  77          */
  78         if (argc == 2 && !strcmp(argv[1], "-h"))
  79                 usage(builtin_log_usage);
  80         argc = setup_revisions(argc, argv, rev, opt);
  81
  82         memset(&w, 0, sizeof(w));
  83         userformat_find_requirements(NULL, &w);
  84
  85         if (!rev->show_notes_given && (!rev->pretty_given || w.notes))
  86                 rev->show_notes = 1;
  87         if (rev->show_notes)
  88                 init_display_notes(&rev->notes_opt);
  89
  90         if (rev->diffopt.pickaxe || rev->diffopt.filter)
  91                 rev->always_show_header = 0;
  92         if (DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES)) {
  93                 rev->always_show_header = 0;
  94                 if (rev->diffopt.nr_paths != 1)
  95                         usage("git logs can only follow renames on one pathname at a time");
  96         }
  97         for (i = 1; i < argc; i++) {
  98                 const char *arg = argv[i];
  99                 if (!strcmp(arg, "--decorate")) {
 100                         decoration_style = DECORATE_SHORT_REFS;
 101                         decoration_given = 1;
 102                 } else if (!prefixcmp(arg, "--decorate=")) {
 103                         const char *v = skip_prefix(arg, "--decorate=");
 104                         decoration_style = parse_decoration_style(arg, v);
 105                         if (decoration_style < 0)
 106                                 die("invalid --decorate option: %s", arg);
 107                         decoration_given = 1;
 108                 } else if (!strcmp(arg, "--no-decorate")) {
 109                         decoration_style = 0;
 110                 } else if (!strcmp(arg, "--source")) {
 111                         rev->show_source = 1;
 112                 } else if (!strcmp(arg, "-h")) {
 113                         usage(builtin_log_usage);
 114                 } else
 115                         die("unrecognized argument: %s", arg);
 116         }
 117
 118         /*
 119          * defeat log.decorate configuration interacting with --pretty=raw
 120          * from the command line.
 121          */
 122         if (!decoration_given && rev->pretty_given
 123             && rev->commit_format == CMIT_FMT_RAW)
 124                 decoration_style = 0;
 125
 126         if (decoration_style) {
 127                 rev->show_decorations = 1;
 128                 load_ref_decorations(decoration_style);
 129         }
 130         setup_pager();
 131 }
 132
 133 static void cmd_log_init(int argc, const char **argv, const char *prefix,
 134                          struct rev_info *rev, struct setup_revision_opt *opt)
 135 {
 136         cmd_log_init_defaults(rev);
 137         cmd_log_init_finish(argc, argv, prefix, rev, opt);
 138 }
 139
 140 /*
 141  * This gives a rough estimate for how many commits we
 142  * will print out in the list.
 143  */
 144 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
 145 {
 146         int n = 0;
 147
 148         while (list) {
 149                 struct commit *commit = list->item;
 150                 unsigned int flags = commit->object.flags;
 151                 list = list->next;
 152                 if (!(flags & (TREESAME | UNINTERESTING)))
 153                         n++;
 154         }
 155         return n;
 156 }
 157
 158 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
 159 {
 160         if (rev->shown_one) {
 161                 rev->shown_one = 0;
 162                 if (rev->commit_format != CMIT_FMT_ONELINE)
 163                         putchar(rev->diffopt.line_termination);
 164         }
 165         printf("Final output: %d %s\n", nr, stage);
 166 }
 167
 168 static struct itimerval early_output_timer;
 169
 170 static void log_show_early(struct rev_info *revs, struct commit_list *list)
 171 {
 172         int i = revs->early_output;
 173         int show_header = 1;
 174
 175         sort_in_topological_order(&list, revs->lifo);
 176         while (list && i) {
 177                 struct commit *commit = list->item;
 178                 switch (simplify_commit(revs, commit)) {
 179                 case commit_show:
 180                         if (show_header) {
 181                                 int n = estimate_commit_count(revs, list);
 182                                 show_early_header(revs, "incomplete", n);
 183                                 show_header = 0;
 184                         }
 185                         log_tree_commit(revs, commit);
 186                         i--;
 187                         break;
 188                 case commit_ignore:
 189                         break;
 190                 case commit_error:
 191                         return;
 192                 }
 193                 list = list->next;
 194         }
 195
 196         /* Did we already get enough commits for the early output? */
 197         if (!i)
 198                 return;
 199
 200         /*
 201          * ..if no, then repeat it twice a second until we
 202          * do.
 203          *
 204          * NOTE! We don't use "it_interval", because if the
 205          * reader isn't listening, we want our output to be
 206          * throttled by the writing, and not have the timer
 207          * trigger every second even if we're blocked on a
 208          * reader!
 209          */
 210         early_output_timer.it_value.tv_sec = 0;
 211         early_output_timer.it_value.tv_usec = 500000;
 212         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 213 }
 214
 215 static void early_output(int signal)
 216 {
 217         show_early_output = log_show_early;
 218 }
 219
 220 static void setup_early_output(struct rev_info *rev)
 221 {
 222         struct sigaction sa;
 223
 224         /*
 225          * Set up the signal handler, minimally intrusively:
 226          * we only set a single volatile integer word (not
 227          * using sigatomic_t - trying to avoid unnecessary
 228          * system dependencies and headers), and using
 229          * SA_RESTART.
 230          */
 231         memset(&sa, 0, sizeof(sa));
 232         sa.sa_handler = early_output;
 233         sigemptyset(&sa.sa_mask);
 234         sa.sa_flags = SA_RESTART;
 235         sigaction(SIGALRM, &sa, NULL);
 236
 237         /*
 238          * If we can get the whole output in less than a
 239          * tenth of a second, don't even bother doing the
 240          * early-output thing..
 241          *
 242          * This is a one-time-only trigger.
 243          */
 244         early_output_timer.it_value.tv_sec = 0;
 245         early_output_timer.it_value.tv_usec = 100000;
 246         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 247 }
 248
 249 static void finish_early_output(struct rev_info *rev)
 250 {
 251         int n = estimate_commit_count(rev, rev->commits);
 252         signal(SIGALRM, SIG_IGN);
 253         show_early_header(rev, "done", n);
 254 }
 255
 256 static int cmd_log_walk(struct rev_info *rev)
 257 {
 258         struct commit *commit;
 259
 260         if (rev->early_output)
 261                 setup_early_output(rev);
 262
 263         if (prepare_revision_walk(rev))
 264                 die("revision walk setup failed");
 265
 266         if (rev->early_output)
 267                 finish_early_output(rev);
 268
 269         /*
 270          * For --check and --exit-code, the exit code is based on CHECK_FAILED
 271          * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
 272          * retain that state information if replacing rev->diffopt in this loop
 273          */
 274         while ((commit = get_revision(rev)) != NULL) {
 275                 log_tree_commit(rev, commit);
 276                 if (!rev->reflog_info) {
 277                         /* we allow cycles in reflog ancestry */
 278                         free(commit->buffer);
 279                         commit->buffer = NULL;
 280                 }
 281                 free_commit_list(commit->parents);
 282                 commit->parents = NULL;
 283         }
 284         if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
 285             DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
 286                 return 02;
 287         }
 288         return diff_result_code(&rev->diffopt, 0);
 289 }
 290
 291 static int git_log_config(const char *var, const char *value, void *cb)
 292 {
 293         if (!strcmp(var, "format.pretty"))
 294                 return git_config_string(&fmt_pretty, var, value);
 295         if (!strcmp(var, "format.subjectprefix"))
 296                 return git_config_string(&fmt_patch_subject_prefix, var, value);
 297         if (!strcmp(var, "log.date"))
 298                 return git_config_string(&default_date_mode, var, value);
 299         if (!strcmp(var, "log.decorate")) {
 300                 decoration_style = parse_decoration_style(var, value);
 301                 if (decoration_style < 0)
 302                         decoration_style = 0; /* maybe warn? */
 303                 return 0;
 304         }
 305         if (!strcmp(var, "log.showroot")) {
 306                 default_show_root = git_config_bool(var, value);
 307                 return 0;
 308         }
 309         if (!prefixcmp(var, "color.decorate."))
 310                 return parse_decorate_color_config(var, 15, value);
 311
 312         return git_diff_ui_config(var, value, cb);
 313 }
 314
 315 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 316 {
 317         struct rev_info rev;
 318         struct setup_revision_opt opt;
 319
 320         git_config(git_log_config, NULL);
 321
 322         if (diff_use_color_default == -1)
 323                 diff_use_color_default = git_use_color_default;
 324
 325         init_revisions(&rev, prefix);
 326         rev.diff = 1;
 327         rev.simplify_history = 0;
 328         memset(&opt, 0, sizeof(opt));
 329         opt.def = "HEAD";
 330         cmd_log_init(argc, argv, prefix, &rev, &opt);
 331         if (!rev.diffopt.output_format)
 332                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
 333         return cmd_log_walk(&rev);
 334 }
 335
 336 static void show_tagger(char *buf, int len, struct rev_info *rev)
 337 {
 338         struct strbuf out = STRBUF_INIT;
 339
 340         pp_user_info("Tagger", rev->commit_format, &out, buf, rev->date_mode,
 341                 get_log_output_encoding());
 342         printf("%s", out.buf);
 343         strbuf_release(&out);
 344 }
 345
 346 static int show_object(const unsigned char *sha1, int show_tag_object,
 347         struct rev_info *rev)
 348 {
 349         unsigned long size;
 350         enum object_type type;
 351         char *buf = read_sha1_file(sha1, &type, &size);
 352         int offset = 0;
 353
 354         if (!buf)
 355                 return error("Could not read object %s", sha1_to_hex(sha1));
 356
 357         if (show_tag_object)
 358                 while (offset < size && buf[offset] != '\n') {
 359                         int new_offset = offset + 1;
 360                         while (new_offset < size && buf[new_offset++] != '\n')
 361                                 ; /* do nothing */
 362                         if (!prefixcmp(buf + offset, "tagger "))
 363                                 show_tagger(buf + offset + 7,
 364                                             new_offset - offset - 7, rev);
 365                         offset = new_offset;
 366                 }
 367
 368         if (offset < size)
 369                 fwrite(buf + offset, size - offset, 1, stdout);
 370         free(buf);
 371         return 0;
 372 }
 373
 374 static int show_tree_object(const unsigned char *sha1,
 375                 const char *base, int baselen,
 376                 const char *pathname, unsigned mode, int stage, void *context)
 377 {
 378         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
 379         return 0;
 380 }
 381
 382 static void show_rev_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
 383 {
 384         if (rev->ignore_merges) {
 385                 /* There was no "-m" on the command line */
 386                 rev->ignore_merges = 0;
 387                 if (!rev->first_parent_only && !rev->combine_merges) {
 388                         /* No "--first-parent", "-c", nor "--cc" */
 389                         rev->combine_merges = 1;
 390                         rev->dense_combined_merges = 1;
 391                 }
 392         }
 393         if (!rev->diffopt.output_format)
 394                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
 395 }
 396
 397 int cmd_show(int argc, const char **argv, const char *prefix)
 398 {
 399         struct rev_info rev;
 400         struct object_array_entry *objects;
 401         struct setup_revision_opt opt;
 402         int i, count, ret = 0;
 403
 404         git_config(git_log_config, NULL);
 405
 406         if (diff_use_color_default == -1)
 407                 diff_use_color_default = git_use_color_default;
 408
 409         init_revisions(&rev, prefix);
 410         rev.diff = 1;
 411         rev.always_show_header = 1;
 412         rev.no_walk = 1;
 413         memset(&opt, 0, sizeof(opt));
 414         opt.def = "HEAD";
 415         opt.tweak = show_rev_tweak_rev;
 416         cmd_log_init(argc, argv, prefix, &rev, &opt);
 417
 418         count = rev.pending.nr;
 419         objects = rev.pending.objects;
 420         for (i = 0; i < count && !ret; i++) {
 421                 struct object *o = objects[i].item;
 422                 const char *name = objects[i].name;
 423                 switch (o->type) {
 424                 case OBJ_BLOB:
 425                         ret = show_object(o->sha1, 0, NULL);
 426                         break;
 427                 case OBJ_TAG: {
 428                         struct tag *t = (struct tag *)o;
 429
 430                         if (rev.shown_one)
 431                                 putchar('\n');
 432                         printf("%stag %s%s\n",
 433                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 434                                         t->tag,
 435                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 436                         ret = show_object(o->sha1, 1, &rev);
 437                         rev.shown_one = 1;
 438                         if (ret)
 439                                 break;
 440                         o = parse_object(t->tagged->sha1);
 441                         if (!o)
 442                                 ret = error("Could not read object %s",
 443                                             sha1_to_hex(t->tagged->sha1));
 444                         objects[i].item = o;
 445                         i--;
 446                         break;
 447                 }
 448                 case OBJ_TREE:
 449                         if (rev.shown_one)
 450                                 putchar('\n');
 451                         printf("%stree %s%s\n\n",
 452                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 453                                         name,
 454                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 455                         read_tree_recursive((struct tree *)o, "", 0, 0, NULL,
 456                                         show_tree_object, NULL);
 457                         rev.shown_one = 1;
 458                         break;
 459                 case OBJ_COMMIT:
 460                         rev.pending.nr = rev.pending.alloc = 0;
 461                         rev.pending.objects = NULL;
 462                         add_object_array(o, name, &rev.pending);
 463                         ret = cmd_log_walk(&rev);
 464                         break;
 465                 default:
 466                         ret = error("Unknown type: %d", o->type);
 467                 }
 468         }
 469         free(objects);
 470         return ret;
 471 }
 472
 473 /*
 474  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
 475  */
 476 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
 477 {
 478         struct rev_info rev;
 479         struct setup_revision_opt opt;
 480
 481         git_config(git_log_config, NULL);
 482
 483         if (diff_use_color_default == -1)
 484                 diff_use_color_default = git_use_color_default;
 485
 486         init_revisions(&rev, prefix);
 487         init_reflog_walk(&rev.reflog_info);
 488         rev.abbrev_commit = 1;
 489         rev.verbose_header = 1;
 490         memset(&opt, 0, sizeof(opt));
 491         opt.def = "HEAD";
 492         cmd_log_init(argc, argv, prefix, &rev, &opt);
 493
 494         /*
 495          * This means that we override whatever commit format the user gave
 496          * on the cmd line.  Sad, but cmd_log_init() currently doesn't
 497          * allow us to set a different default.
 498          */
 499         rev.commit_format = CMIT_FMT_ONELINE;
 500         rev.use_terminator = 1;
 501         rev.always_show_header = 1;
 502
 503         return cmd_log_walk(&rev);
 504 }
 505
 506 int cmd_log(int argc, const char **argv, const char *prefix)
 507 {
 508         struct rev_info rev;
 509         struct setup_revision_opt opt;
 510
 511         git_config(git_log_config, NULL);
 512
 513         if (diff_use_color_default == -1)
 514                 diff_use_color_default = git_use_color_default;
 515
 516         init_revisions(&rev, prefix);
 517         rev.always_show_header = 1;
 518         memset(&opt, 0, sizeof(opt));
 519         opt.def = "HEAD";
 520         cmd_log_init(argc, argv, prefix, &rev, &opt);
 521         return cmd_log_walk(&rev);
 522 }
 523
 524 /* format-patch */
 525
 526 static const char *fmt_patch_suffix = ".patch";
 527 static int numbered = 0;
 528 static int auto_number = 1;
 529
 530 static char *default_attach = NULL;
 531
 532 static struct string_list extra_hdr;
 533 static struct string_list extra_to;
 534 static struct string_list extra_cc;
 535
 536 static void add_header(const char *value)
 537 {
 538         struct string_list_item *item;
 539         int len = strlen(value);
 540         while (len && value[len - 1] == '\n')
 541                 len--;
 542
 543         if (!strncasecmp(value, "to: ", 4)) {
 544                 item = string_list_append(&extra_to, value + 4);
 545                 len -= 4;
 546         } else if (!strncasecmp(value, "cc: ", 4)) {
 547                 item = string_list_append(&extra_cc, value + 4);
 548                 len -= 4;
 549         } else {
 550                 item = string_list_append(&extra_hdr, value);
 551         }
 552
 553         item->string[len] = '\0';
 554 }
 555
 556 #define THREAD_SHALLOW 1
 557 #define THREAD_DEEP 2
 558 static int thread;
 559 static int do_signoff;
 560 static const char *signature = git_version_string;
 561
 562 static int git_format_config(const char *var, const char *value, void *cb)
 563 {
 564         if (!strcmp(var, "format.headers")) {
 565                 if (!value)
 566                         die("format.headers without value");
 567                 add_header(value);
 568                 return 0;
 569         }
 570         if (!strcmp(var, "format.suffix"))
 571                 return git_config_string(&fmt_patch_suffix, var, value);
 572         if (!strcmp(var, "format.to")) {
 573                 if (!value)
 574                         return config_error_nonbool(var);
 575                 string_list_append(&extra_to, value);
 576                 return 0;
 577         }
 578         if (!strcmp(var, "format.cc")) {
 579                 if (!value)
 580                         return config_error_nonbool(var);
 581                 string_list_append(&extra_cc, value);
 582                 return 0;
 583         }
 584         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
 585                 return 0;
 586         }
 587         if (!strcmp(var, "format.numbered")) {
 588                 if (value && !strcasecmp(value, "auto")) {
 589                         auto_number = 1;
 590                         return 0;
 591                 }
 592                 numbered = git_config_bool(var, value);
 593                 auto_number = auto_number && numbered;
 594                 return 0;
 595         }
 596         if (!strcmp(var, "format.attach")) {
 597                 if (value && *value)
 598                         default_attach = xstrdup(value);
 599                 else
 600                         default_attach = xstrdup(git_version_string);
 601                 return 0;
 602         }
 603         if (!strcmp(var, "format.thread")) {
 604                 if (value && !strcasecmp(value, "deep")) {
 605                         thread = THREAD_DEEP;
 606                         return 0;
 607                 }
 608                 if (value && !strcasecmp(value, "shallow")) {
 609                         thread = THREAD_SHALLOW;
 610                         return 0;
 611                 }
 612                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
 613                 return 0;
 614         }
 615         if (!strcmp(var, "format.signoff")) {
 616                 do_signoff = git_config_bool(var, value);
 617                 return 0;
 618         }
 619         if (!strcmp(var, "format.signature"))
 620                 return git_config_string(&signature, var, value);
 621
 622         return git_log_config(var, value, cb);
 623 }
 624
 625 static FILE *realstdout = NULL;
 626 static const char *output_directory = NULL;
 627 static int outdir_offset;
 628
 629 static int reopen_stdout(struct commit *commit, struct rev_info *rev)
 630 {
 631         struct strbuf filename = STRBUF_INIT;
 632         int suffix_len = strlen(fmt_patch_suffix) + 1;
 633
 634         if (output_directory) {
 635                 strbuf_addstr(&filename, output_directory);
 636                 if (filename.len >=
 637                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
 638                         return error("name of output directory is too long");
 639                 if (filename.buf[filename.len - 1] != '/')
 640                         strbuf_addch(&filename, '/');
 641         }
 642
 643         get_patch_filename(commit, rev->nr, fmt_patch_suffix, &filename);
 644
 645         if (!DIFF_OPT_TST(&rev->diffopt, QUICK))
 646                 fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
 647
 648         if (freopen(filename.buf, "w", stdout) == NULL)
 649                 return error("Cannot open patch file %s", filename.buf);
 650
 651         strbuf_release(&filename);
 652         return 0;
 653 }
 654
 655 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids, const char *prefix)
 656 {
 657         struct rev_info check_rev;
 658         struct commit *commit;
 659         struct object *o1, *o2;
 660         unsigned flags1, flags2;
 661
 662         if (rev->pending.nr != 2)
 663                 die("Need exactly one range.");
 664
 665         o1 = rev->pending.objects[0].item;
 666         flags1 = o1->flags;
 667         o2 = rev->pending.objects[1].item;
 668         flags2 = o2->flags;
 669
 670         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
 671                 die("Not a range.");
 672
 673         init_patch_ids(ids);
 674
 675         /* given a range a..b get all patch ids for b..a */
 676         init_revisions(&check_rev, prefix);
 677         o1->flags ^= UNINTERESTING;
 678         o2->flags ^= UNINTERESTING;
 679         add_pending_object(&check_rev, o1, "o1");
 680         add_pending_object(&check_rev, o2, "o2");
 681         if (prepare_revision_walk(&check_rev))
 682                 die("revision walk setup failed");
 683
 684         while ((commit = get_revision(&check_rev)) != NULL) {
 685                 /* ignore merges */
 686                 if (commit->parents && commit->parents->next)
 687                         continue;
 688
 689                 add_commit_patch_id(commit, ids);
 690         }
 691
 692         /* reset for next revision walk */
 693         clear_commit_marks((struct commit *)o1,
 694                         SEEN | UNINTERESTING | SHOWN | ADDED);
 695         clear_commit_marks((struct commit *)o2,
 696                         SEEN | UNINTERESTING | SHOWN | ADDED);
 697         o1->flags = flags1;
 698         o2->flags = flags2;
 699 }
 700
 701 static void gen_message_id(struct rev_info *info, char *base)
 702 {
 703         const char *committer = git_committer_info(IDENT_WARN_ON_NO_NAME);
 704         const char *email_start = strrchr(committer, '<');
 705         const char *email_end = strrchr(committer, '>');
 706         struct strbuf buf = STRBUF_INIT;
 707         if (!email_start || !email_end || email_start > email_end - 1)
 708                 die("Could not extract email from committer identity.");
 709         strbuf_addf(&buf, "%s.%lu.git.%.*s", base,
 710                     (unsigned long) time(NULL),
 711                     (int)(email_end - email_start - 1), email_start + 1);
 712         info->message_id = strbuf_detach(&buf, NULL);
 713 }
 714
 715 static void print_signature(void)
 716 {
 717         if (signature && *signature)
 718                 printf("-- \n%s\n\n", signature);
 719 }
 720
 721 static void make_cover_letter(struct rev_info *rev, int use_stdout,
 722                               int numbered, int numbered_files,
 723                               struct commit *origin,
 724                               int nr, struct commit **list, struct commit *head)
 725 {
 726         const char *committer;
 727         const char *subject_start = NULL;
 728         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
 729         const char *msg;
 730         const char *extra_headers = rev->extra_headers;
 731         struct shortlog log;
 732         struct strbuf sb = STRBUF_INIT;
 733         int i;
 734         const char *encoding = "UTF-8";
 735         struct diff_options opts;
 736         int need_8bit_cte = 0;
 737         struct commit *commit = NULL;
 738
 739         if (rev->commit_format != CMIT_FMT_EMAIL)
 740                 die("Cover letter needs email format");
 741
 742         committer = git_committer_info(0);
 743
 744         if (!numbered_files) {
 745                 /*
 746                  * We fake a commit for the cover letter so we get the filename
 747                  * desired.
 748                  */
 749                 commit = xcalloc(1, sizeof(*commit));
 750                 commit->buffer = xmalloc(400);
 751                 snprintf(commit->buffer, 400,
 752                         "tree 0000000000000000000000000000000000000000\n"
 753                         "parent %s\n"
 754                         "author %s\n"
 755                         "committer %s\n\n"
 756                         "cover letter\n",
 757                         sha1_to_hex(head->object.sha1), committer, committer);
 758         }
 759
 760         if (!use_stdout && reopen_stdout(commit, rev))
 761                 return;
 762
 763         if (commit) {
 764
 765                 free(commit->buffer);
 766                 free(commit);
 767         }
 768
 769         log_write_email_headers(rev, head, &subject_start, &extra_headers,
 770                                 &need_8bit_cte);
 771
 772         for (i = 0; !need_8bit_cte && i < nr; i++)
 773                 if (has_non_ascii(list[i]->buffer))
 774                         need_8bit_cte = 1;
 775
 776         msg = body;
 777         pp_user_info(NULL, CMIT_FMT_EMAIL, &sb, committer, DATE_RFC2822,
 778                      encoding);
 779         pp_title_line(CMIT_FMT_EMAIL, &msg, &sb, subject_start, extra_headers,
 780                       encoding, need_8bit_cte);
 781         pp_remainder(CMIT_FMT_EMAIL, &msg, &sb, 0);
 782         printf("%s\n", sb.buf);
 783
 784         strbuf_release(&sb);
 785
 786         shortlog_init(&log);
 787         log.wrap_lines = 1;
 788         log.wrap = 72;
 789         log.in1 = 2;
 790         log.in2 = 4;
 791         for (i = 0; i < nr; i++)
 792                 shortlog_add_commit(&log, list[i]);
 793
 794         shortlog_output(&log);
 795
 796         /*
 797          * We can only do diffstat with a unique reference point
 798          */
 799         if (!origin)
 800                 return;
 801
 802         memcpy(&opts, &rev->diffopt, sizeof(opts));
 803         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
 804
 805         diff_setup_done(&opts);
 806
 807         diff_tree_sha1(origin->tree->object.sha1,
 808                        head->tree->object.sha1,
 809                        "", &opts);
 810         diffcore_std(&opts);
 811         diff_flush(&opts);
 812
 813         printf("\n");
 814         print_signature();
 815 }
 816
 817 static const char *clean_message_id(const char *msg_id)
 818 {
 819         char ch;
 820         const char *a, *z, *m;
 821
 822         m = msg_id;
 823         while ((ch = *m) && (isspace(ch) || (ch == '<')))
 824                 m++;
 825         a = m;
 826         z = NULL;
 827         while ((ch = *m)) {
 828                 if (!isspace(ch) && (ch != '>'))
 829                         z = m;
 830                 m++;
 831         }
 832         if (!z)
 833                 die("insane in-reply-to: %s", msg_id);
 834         if (++z == m)
 835                 return a;
 836         return xmemdupz(a, z - a);
 837 }
 838
 839 static const char *set_outdir(const char *prefix, const char *output_directory)
 840 {
 841         if (output_directory && is_absolute_path(output_directory))
 842                 return output_directory;
 843
 844         if (!prefix || !*prefix) {
 845                 if (output_directory)
 846                         return output_directory;
 847                 /* The user did not explicitly ask for "./" */
 848                 outdir_offset = 2;
 849                 return "./";
 850         }
 851
 852         outdir_offset = strlen(prefix);
 853         if (!output_directory)
 854                 return prefix;
 855
 856         return xstrdup(prefix_filename(prefix, outdir_offset,
 857                                        output_directory));
 858 }
 859
 860 static const char * const builtin_format_patch_usage[] = {
 861         "git format-patch [options] [<since> | <revision range>]",
 862         NULL
 863 };
 864
 865 static int keep_subject = 0;
 866
 867 static int keep_callback(const struct option *opt, const char *arg, int unset)
 868 {
 869         ((struct rev_info *)opt->value)->total = -1;
 870         keep_subject = 1;
 871         return 0;
 872 }
 873
 874 static int subject_prefix = 0;
 875
 876 static int subject_prefix_callback(const struct option *opt, const char *arg,
 877                             int unset)
 878 {
 879         subject_prefix = 1;
 880         ((struct rev_info *)opt->value)->subject_prefix = arg;
 881         return 0;
 882 }
 883
 884 static int numbered_cmdline_opt = 0;
 885
 886 static int numbered_callback(const struct option *opt, const char *arg,
 887                              int unset)
 888 {
 889         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
 890         if (unset)
 891                 auto_number =  0;
 892         return 0;
 893 }
 894
 895 static int no_numbered_callback(const struct option *opt, const char *arg,
 896                                 int unset)
 897 {
 898         return numbered_callback(opt, arg, 1);
 899 }
 900
 901 static int output_directory_callback(const struct option *opt, const char *arg,
 902                               int unset)
 903 {
 904         const char **dir = (const char **)opt->value;
 905         if (*dir)
 906                 die("Two output directories?");
 907         *dir = arg;
 908         return 0;
 909 }
 910
 911 static int thread_callback(const struct option *opt, const char *arg, int unset)
 912 {
 913         int *thread = (int *)opt->value;
 914         if (unset)
 915                 *thread = 0;
 916         else if (!arg || !strcmp(arg, "shallow"))
 917                 *thread = THREAD_SHALLOW;
 918         else if (!strcmp(arg, "deep"))
 919                 *thread = THREAD_DEEP;
 920         else
 921                 return 1;
 922         return 0;
 923 }
 924
 925 static int attach_callback(const struct option *opt, const char *arg, int unset)
 926 {
 927         struct rev_info *rev = (struct rev_info *)opt->value;
 928         if (unset)
 929                 rev->mime_boundary = NULL;
 930         else if (arg)
 931                 rev->mime_boundary = arg;
 932         else
 933                 rev->mime_boundary = git_version_string;
 934         rev->no_inline = unset ? 0 : 1;
 935         return 0;
 936 }
 937
 938 static int inline_callback(const struct option *opt, const char *arg, int unset)
 939 {
 940         struct rev_info *rev = (struct rev_info *)opt->value;
 941         if (unset)
 942                 rev->mime_boundary = NULL;
 943         else if (arg)
 944                 rev->mime_boundary = arg;
 945         else
 946                 rev->mime_boundary = git_version_string;
 947         rev->no_inline = 0;
 948         return 0;
 949 }
 950
 951 static int header_callback(const struct option *opt, const char *arg, int unset)
 952 {
 953         if (unset) {
 954                 string_list_clear(&extra_hdr, 0);
 955                 string_list_clear(&extra_to, 0);
 956                 string_list_clear(&extra_cc, 0);
 957         } else {
 958             add_header(arg);
 959         }
 960         return 0;
 961 }
 962
 963 static int to_callback(const struct option *opt, const char *arg, int unset)
 964 {
 965         if (unset)
 966                 string_list_clear(&extra_to, 0);
 967         else
 968                 string_list_append(&extra_to, arg);
 969         return 0;
 970 }
 971
 972 static int cc_callback(const struct option *opt, const char *arg, int unset)
 973 {
 974         if (unset)
 975                 string_list_clear(&extra_cc, 0);
 976         else
 977                 string_list_append(&extra_cc, arg);
 978         return 0;
 979 }
 980
 981 int cmd_format_patch(int argc, const char **argv, const char *prefix)
 982 {
 983         struct commit *commit;
 984         struct commit **list = NULL;
 985         struct rev_info rev;
 986         struct setup_revision_opt s_r_opt;
 987         int nr = 0, total, i;
 988         int use_stdout = 0;
 989         int start_number = -1;
 990         int numbered_files = 0;         /* _just_ numbers */
 991         int ignore_if_in_upstream = 0;
 992         int cover_letter = 0;
 993         int boundary_count = 0;
 994         int no_binary_diff = 0;
 995         struct commit *origin = NULL, *head = NULL;
 996         const char *in_reply_to = NULL;
 997         struct patch_ids ids;
 998         char *add_signoff = NULL;
 999         struct strbuf buf = STRBUF_INIT;
1000         int use_patch_format = 0;
1001         const struct option builtin_format_patch_options[] = {
1002                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
1003                             "use [PATCH n/m] even with a single patch",
1004                             PARSE_OPT_NOARG, numbered_callback },
1005                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
1006                             "use [PATCH] even with multiple patches",
1007                             PARSE_OPT_NOARG, no_numbered_callback },
1008                 OPT_BOOLEAN('s', "signoff", &do_signoff, "add Signed-off-by:"),
1009                 OPT_BOOLEAN(0, "stdout", &use_stdout,
1010                             "print patches to standard out"),
1011                 OPT_BOOLEAN(0, "cover-letter", &cover_letter,
1012                             "generate a cover letter"),
1013                 OPT_BOOLEAN(0, "numbered-files", &numbered_files,
1014                             "use simple number sequence for output file names"),
1015                 OPT_STRING(0, "suffix", &fmt_patch_suffix, "sfx",
1016                             "use <sfx> instead of '.patch'"),
1017                 OPT_INTEGER(0, "start-number", &start_number,
1018                             "start numbering patches at <n> instead of 1"),
1019                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, "prefix",
1020                             "Use [<prefix>] instead of [PATCH]",
1021                             PARSE_OPT_NONEG, subject_prefix_callback },
1022                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
1023                             "dir", "store resulting files in <dir>",
1024                             PARSE_OPT_NONEG, output_directory_callback },
1025                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
1026                             "don't strip/add [PATCH]",
1027                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
1028                 OPT_BOOLEAN(0, "no-binary", &no_binary_diff,
1029                             "don't output binary diffs"),
1030                 OPT_BOOLEAN(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
1031                             "don't include a patch matching a commit upstream"),
1032                 { OPTION_BOOLEAN, 'p', "no-stat", &use_patch_format, NULL,
1033                   "show patch format instead of default (patch + stat)",
1034                   PARSE_OPT_NONEG | PARSE_OPT_NOARG },
1035                 OPT_GROUP("Messaging"),
1036                 { OPTION_CALLBACK, 0, "add-header", NULL, "header",
1037                             "add email header", 0, header_callback },
1038                 { OPTION_CALLBACK, 0, "to", NULL, "email", "add To: header",
1039                             0, to_callback },
1040                 { OPTION_CALLBACK, 0, "cc", NULL, "email", "add Cc: header",
1041                             0, cc_callback },
1042                 OPT_STRING(0, "in-reply-to", &in_reply_to, "message-id",
1043                             "make first mail a reply to <message-id>"),
1044                 { OPTION_CALLBACK, 0, "attach", &rev, "boundary",
1045                             "attach the patch", PARSE_OPT_OPTARG,
1046                             attach_callback },
1047                 { OPTION_CALLBACK, 0, "inline", &rev, "boundary",
1048                             "inline the patch",
1049                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
1050                             inline_callback },
1051                 { OPTION_CALLBACK, 0, "thread", &thread, "style",
1052                             "enable message threading, styles: shallow, deep",
1053                             PARSE_OPT_OPTARG, thread_callback },
1054                 OPT_STRING(0, "signature", &signature, "signature",
1055                             "add a signature"),
1056                 OPT_END()
1057         };
1058
1059         extra_hdr.strdup_strings = 1;
1060         extra_to.strdup_strings = 1;
1061         extra_cc.strdup_strings = 1;
1062         git_config(git_format_config, NULL);
1063         init_revisions(&rev, prefix);
1064         rev.commit_format = CMIT_FMT_EMAIL;
1065         rev.verbose_header = 1;
1066         rev.diff = 1;
1067         rev.no_merges = 1;
1068         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
1069         rev.subject_prefix = fmt_patch_subject_prefix;
1070         memset(&s_r_opt, 0, sizeof(s_r_opt));
1071         s_r_opt.def = "HEAD";
1072
1073         if (default_attach) {
1074                 rev.mime_boundary = default_attach;
1075                 rev.no_inline = 1;
1076         }
1077
1078         /*
1079          * Parse the arguments before setup_revisions(), or something
1080          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1081          * possibly a valid SHA1.
1082          */
1083         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1084                              builtin_format_patch_usage,
1085                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1086                              PARSE_OPT_KEEP_DASHDASH);
1087
1088         if (do_signoff) {
1089                 const char *committer;
1090                 const char *endpos;
1091                 committer = git_committer_info(IDENT_ERROR_ON_NO_NAME);
1092                 endpos = strchr(committer, '>');
1093                 if (!endpos)
1094                         die("bogus committer info %s", committer);
1095                 add_signoff = xmemdupz(committer, endpos - committer + 1);
1096         }
1097
1098         for (i = 0; i < extra_hdr.nr; i++) {
1099                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1100                 strbuf_addch(&buf, '\n');
1101         }
1102
1103         if (extra_to.nr)
1104                 strbuf_addstr(&buf, "To: ");
1105         for (i = 0; i < extra_to.nr; i++) {
1106                 if (i)
1107                         strbuf_addstr(&buf, "    ");
1108                 strbuf_addstr(&buf, extra_to.items[i].string);
1109                 if (i + 1 < extra_to.nr)
1110                         strbuf_addch(&buf, ',');
1111                 strbuf_addch(&buf, '\n');
1112         }
1113
1114         if (extra_cc.nr)
1115                 strbuf_addstr(&buf, "Cc: ");
1116         for (i = 0; i < extra_cc.nr; i++) {
1117                 if (i)
1118                         strbuf_addstr(&buf, "    ");
1119                 strbuf_addstr(&buf, extra_cc.items[i].string);
1120                 if (i + 1 < extra_cc.nr)
1121                         strbuf_addch(&buf, ',');
1122                 strbuf_addch(&buf, '\n');
1123         }
1124
1125         rev.extra_headers = strbuf_detach(&buf, NULL);
1126
1127         if (start_number < 0)
1128                 start_number = 1;
1129
1130         /*
1131          * If numbered is set solely due to format.numbered in config,
1132          * and it would conflict with --keep-subject (-k) from the
1133          * command line, reset "numbered".
1134          */
1135         if (numbered && keep_subject && !numbered_cmdline_opt)
1136                 numbered = 0;
1137
1138         if (numbered && keep_subject)
1139                 die ("-n and -k are mutually exclusive.");
1140         if (keep_subject && subject_prefix)
1141                 die ("--subject-prefix and -k are mutually exclusive.");
1142
1143         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1144         if (argc > 1)
1145                 die ("unrecognized argument: %s", argv[1]);
1146
1147         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1148                 die("--name-only does not make sense");
1149         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1150                 die("--name-status does not make sense");
1151         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1152                 die("--check does not make sense");
1153
1154         if (!use_patch_format &&
1155                 (!rev.diffopt.output_format ||
1156                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1157                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1158
1159         /* Always generate a patch */
1160         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1161
1162         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1163                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1164
1165         if (rev.show_notes)
1166                 init_display_notes(&rev.notes_opt);
1167
1168         if (!use_stdout)
1169                 output_directory = set_outdir(prefix, output_directory);
1170         else
1171                 setup_pager();
1172
1173         if (output_directory) {
1174                 if (use_stdout)
1175                         die("standard output, or directory, which one?");
1176                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1177                         die_errno("Could not create directory '%s'",
1178                                   output_directory);
1179         }
1180
1181         if (rev.pending.nr == 1) {
1182                 if (rev.max_count < 0 && !rev.show_root_diff) {
1183                         /*
1184                          * This is traditional behaviour of "git format-patch
1185                          * origin" that prepares what the origin side still
1186                          * does not have.
1187                          */
1188                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1189                         add_head_to_pending(&rev);
1190                 }
1191                 /*
1192                  * Otherwise, it is "format-patch -22 HEAD", and/or
1193                  * "format-patch --root HEAD".  The user wants
1194                  * get_revision() to do the usual traversal.
1195                  */
1196         }
1197
1198         /*
1199          * We cannot move this anywhere earlier because we do want to
1200          * know if --root was given explicitly from the command line.
1201          */
1202         rev.show_root_diff = 1;
1203
1204         if (cover_letter) {
1205                 /* remember the range */
1206                 int i;
1207                 for (i = 0; i < rev.pending.nr; i++) {
1208                         struct object *o = rev.pending.objects[i].item;
1209                         if (!(o->flags & UNINTERESTING))
1210                                 head = (struct commit *)o;
1211                 }
1212                 /* We can't generate a cover letter without any patches */
1213                 if (!head)
1214                         return 0;
1215         }
1216
1217         if (ignore_if_in_upstream) {
1218                 /* Don't say anything if head and upstream are the same. */
1219                 if (rev.pending.nr == 2) {
1220                         struct object_array_entry *o = rev.pending.objects;
1221                         if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1222                                 return 0;
1223                 }
1224                 get_patch_ids(&rev, &ids, prefix);
1225         }
1226
1227         if (!use_stdout)
1228                 realstdout = xfdopen(xdup(1), "w");
1229
1230         if (prepare_revision_walk(&rev))
1231                 die("revision walk setup failed");
1232         rev.boundary = 1;
1233         while ((commit = get_revision(&rev)) != NULL) {
1234                 if (commit->object.flags & BOUNDARY) {
1235                         boundary_count++;
1236                         origin = (boundary_count == 1) ? commit : NULL;
1237                         continue;
1238                 }
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 static void print_commit(char sign, struct commit *commit, int verbose,
1365                          int abbrev)
1366 {
1367         if (!verbose) {
1368                 printf("%c %s\n", sign,
1369                        find_unique_abbrev(commit->object.sha1, abbrev));
1370         } else {
1371                 struct strbuf buf = STRBUF_INIT;
1372                 struct pretty_print_context ctx = {0};
1373                 pretty_print_commit(CMIT_FMT_ONELINE, commit, &buf, &ctx);
1374                 printf("%c %s %s\n", sign,
1375                        find_unique_abbrev(commit->object.sha1, abbrev),
1376                        buf.buf);
1377                 strbuf_release(&buf);
1378         }
1379 }
1380
1381 int cmd_cherry(int argc, const char **argv, const char *prefix)
1382 {
1383         struct rev_info revs;
1384         struct patch_ids ids;
1385         struct commit *commit;
1386         struct commit_list *list = NULL;
1387         struct branch *current_branch;
1388         const char *upstream;
1389         const char *head = "HEAD";
1390         const char *limit = NULL;
1391         int verbose = 0, abbrev = 0;
1392
1393         struct option options[] = {
1394                 OPT__ABBREV(&abbrev),
1395                 OPT__VERBOSE(&verbose, "be verbose"),
1396                 OPT_END()
1397         };
1398
1399         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
1400
1401         switch (argc) {
1402         case 3:
1403                 limit = argv[2];
1404                 /* FALLTHROUGH */
1405         case 2:
1406                 head = argv[1];
1407                 /* FALLTHROUGH */
1408         case 1:
1409                 upstream = argv[0];
1410                 break;
1411         default:
1412                 current_branch = branch_get(NULL);
1413                 if (!current_branch || !current_branch->merge
1414                                         || !current_branch->merge[0]
1415                                         || !current_branch->merge[0]->dst) {
1416                         fprintf(stderr, "Could not find a tracked"
1417                                         " remote branch, please"
1418                                         " specify <upstream> manually.\n");
1419                         usage_with_options(cherry_usage, options);
1420                 }
1421
1422                 upstream = current_branch->merge[0]->dst;
1423         }
1424
1425         init_revisions(&revs, prefix);
1426         revs.diff = 1;
1427         revs.combine_merges = 0;
1428         revs.ignore_merges = 1;
1429         DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
1430
1431         if (add_pending_commit(head, &revs, 0))
1432                 die("Unknown commit %s", head);
1433         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1434                 die("Unknown commit %s", upstream);
1435
1436         /* Don't say anything if head and upstream are the same. */
1437         if (revs.pending.nr == 2) {
1438                 struct object_array_entry *o = revs.pending.objects;
1439                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1440                         return 0;
1441         }
1442
1443         get_patch_ids(&revs, &ids, prefix);
1444
1445         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1446                 die("Unknown commit %s", limit);
1447
1448         /* reverse the list of commits */
1449         if (prepare_revision_walk(&revs))
1450                 die("revision walk setup failed");
1451         while ((commit = get_revision(&revs)) != NULL) {
1452                 /* ignore merges */
1453                 if (commit->parents && commit->parents->next)
1454                         continue;
1455
1456                 commit_list_insert(commit, &list);
1457         }
1458
1459         while (list) {
1460                 char sign = '+';
1461
1462                 commit = list->item;
1463                 if (has_commit_patch_id(commit, &ids))
1464                         sign = '-';
1465                 print_commit(sign, commit, verbose, abbrev);
1466                 list = list->next;
1467         }
1468
1469         free_patch_ids(&ids);
1470         return 0;
1471 }