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.pathspec.nr != 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         setup_pager();
 129 }
 130
 131 /*
 132  * This gives a rough estimate for how many commits we
 133  * will print out in the list.
 134  */
 135 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
 136 {
 137         int n = 0;
 138
 139         while (list) {
 140                 struct commit *commit = list->item;
 141                 unsigned int flags = commit->object.flags;
 142                 list = list->next;
 143                 if (!(flags & (TREESAME | UNINTERESTING)))
 144                         n++;
 145         }
 146         return n;
 147 }
 148
 149 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
 150 {
 151         if (rev->shown_one) {
 152                 rev->shown_one = 0;
 153                 if (rev->commit_format != CMIT_FMT_ONELINE)
 154                         putchar(rev->diffopt.line_termination);
 155         }
 156         printf(_("Final output: %d %s\n"), nr, stage);
 157 }
 158
 159 static struct itimerval early_output_timer;
 160
 161 static void log_show_early(struct rev_info *revs, struct commit_list *list)
 162 {
 163         int i = revs->early_output;
 164         int show_header = 1;
 165
 166         sort_in_topological_order(&list, revs->lifo);
 167         while (list && i) {
 168                 struct commit *commit = list->item;
 169                 switch (simplify_commit(revs, commit)) {
 170                 case commit_show:
 171                         if (show_header) {
 172                                 int n = estimate_commit_count(revs, list);
 173                                 show_early_header(revs, "incomplete", n);
 174                                 show_header = 0;
 175                         }
 176                         log_tree_commit(revs, commit);
 177                         i--;
 178                         break;
 179                 case commit_ignore:
 180                         break;
 181                 case commit_error:
 182                         return;
 183                 }
 184                 list = list->next;
 185         }
 186
 187         /* Did we already get enough commits for the early output? */
 188         if (!i)
 189                 return;
 190
 191         /*
 192          * ..if no, then repeat it twice a second until we
 193          * do.
 194          *
 195          * NOTE! We don't use "it_interval", because if the
 196          * reader isn't listening, we want our output to be
 197          * throttled by the writing, and not have the timer
 198          * trigger every second even if we're blocked on a
 199          * reader!
 200          */
 201         early_output_timer.it_value.tv_sec = 0;
 202         early_output_timer.it_value.tv_usec = 500000;
 203         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 204 }
 205
 206 static void early_output(int signal)
 207 {
 208         show_early_output = log_show_early;
 209 }
 210
 211 static void setup_early_output(struct rev_info *rev)
 212 {
 213         struct sigaction sa;
 214
 215         /*
 216          * Set up the signal handler, minimally intrusively:
 217          * we only set a single volatile integer word (not
 218          * using sigatomic_t - trying to avoid unnecessary
 219          * system dependencies and headers), and using
 220          * SA_RESTART.
 221          */
 222         memset(&sa, 0, sizeof(sa));
 223         sa.sa_handler = early_output;
 224         sigemptyset(&sa.sa_mask);
 225         sa.sa_flags = SA_RESTART;
 226         sigaction(SIGALRM, &sa, NULL);
 227
 228         /*
 229          * If we can get the whole output in less than a
 230          * tenth of a second, don't even bother doing the
 231          * early-output thing..
 232          *
 233          * This is a one-time-only trigger.
 234          */
 235         early_output_timer.it_value.tv_sec = 0;
 236         early_output_timer.it_value.tv_usec = 100000;
 237         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 238 }
 239
 240 static void finish_early_output(struct rev_info *rev)
 241 {
 242         int n = estimate_commit_count(rev, rev->commits);
 243         signal(SIGALRM, SIG_IGN);
 244         show_early_header(rev, "done", n);
 245 }
 246
 247 static int cmd_log_walk(struct rev_info *rev)
 248 {
 249         struct commit *commit;
 250
 251         if (rev->early_output)
 252                 setup_early_output(rev);
 253
 254         if (prepare_revision_walk(rev))
 255                 die(_("revision walk setup failed"));
 256
 257         if (rev->early_output)
 258                 finish_early_output(rev);
 259
 260         /*
 261          * For --check and --exit-code, the exit code is based on CHECK_FAILED
 262          * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
 263          * retain that state information if replacing rev->diffopt in this loop
 264          */
 265         while ((commit = get_revision(rev)) != NULL) {
 266                 if (!log_tree_commit(rev, commit) &&
 267                     rev->max_count >= 0)
 268                         /*
 269                          * We decremented max_count in get_revision,
 270                          * but we didn't actually show the commit.
 271                          */
 272                         rev->max_count++;
 273                 if (!rev->reflog_info) {
 274                         /* we allow cycles in reflog ancestry */
 275                         free(commit->buffer);
 276                         commit->buffer = NULL;
 277                 }
 278                 free_commit_list(commit->parents);
 279                 commit->parents = NULL;
 280         }
 281         if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
 282             DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
 283                 return 02;
 284         }
 285         return diff_result_code(&rev->diffopt, 0);
 286 }
 287
 288 static int git_log_config(const char *var, const char *value, void *cb)
 289 {
 290         if (!strcmp(var, "format.pretty"))
 291                 return git_config_string(&fmt_pretty, var, value);
 292         if (!strcmp(var, "format.subjectprefix"))
 293                 return git_config_string(&fmt_patch_subject_prefix, var, value);
 294         if (!strcmp(var, "log.date"))
 295                 return git_config_string(&default_date_mode, var, value);
 296         if (!strcmp(var, "log.decorate")) {
 297                 decoration_style = parse_decoration_style(var, value);
 298                 if (decoration_style < 0)
 299                         decoration_style = 0; /* maybe warn? */
 300                 return 0;
 301         }
 302         if (!strcmp(var, "log.showroot")) {
 303                 default_show_root = git_config_bool(var, value);
 304                 return 0;
 305         }
 306         if (!prefixcmp(var, "color.decorate."))
 307                 return parse_decorate_color_config(var, 15, value);
 308
 309         return git_diff_ui_config(var, value, cb);
 310 }
 311
 312 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 313 {
 314         struct rev_info rev;
 315         struct setup_revision_opt opt;
 316
 317         git_config(git_log_config, NULL);
 318
 319         if (diff_use_color_default == -1)
 320                 diff_use_color_default = git_use_color_default;
 321
 322         init_revisions(&rev, prefix);
 323         rev.diff = 1;
 324         rev.simplify_history = 0;
 325         memset(&opt, 0, sizeof(opt));
 326         opt.def = "HEAD";
 327         cmd_log_init(argc, argv, prefix, &rev, &opt);
 328         if (!rev.diffopt.output_format)
 329                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
 330         return cmd_log_walk(&rev);
 331 }
 332
 333 static void show_tagger(char *buf, int len, struct rev_info *rev)
 334 {
 335         struct strbuf out = STRBUF_INIT;
 336
 337         pp_user_info("Tagger", rev->commit_format, &out, buf, rev->date_mode,
 338                 get_log_output_encoding());
 339         printf("%s", out.buf);
 340         strbuf_release(&out);
 341 }
 342
 343 static int show_object(const unsigned char *sha1, int show_tag_object,
 344         struct rev_info *rev)
 345 {
 346         unsigned long size;
 347         enum object_type type;
 348         char *buf = read_sha1_file(sha1, &type, &size);
 349         int offset = 0;
 350
 351         if (!buf)
 352                 return error(_("Could not read object %s"), sha1_to_hex(sha1));
 353
 354         if (show_tag_object)
 355                 while (offset < size && buf[offset] != '\n') {
 356                         int new_offset = offset + 1;
 357                         while (new_offset < size && buf[new_offset++] != '\n')
 358                                 ; /* do nothing */
 359                         if (!prefixcmp(buf + offset, "tagger "))
 360                                 show_tagger(buf + offset + 7,
 361                                             new_offset - offset - 7, rev);
 362                         offset = new_offset;
 363                 }
 364
 365         if (offset < size)
 366                 fwrite(buf + offset, size - offset, 1, stdout);
 367         free(buf);
 368         return 0;
 369 }
 370
 371 static int show_tree_object(const unsigned char *sha1,
 372                 const char *base, int baselen,
 373                 const char *pathname, unsigned mode, int stage, void *context)
 374 {
 375         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
 376         return 0;
 377 }
 378
 379 static void show_rev_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
 380 {
 381         if (rev->ignore_merges) {
 382                 /* There was no "-m" on the command line */
 383                 rev->ignore_merges = 0;
 384                 if (!rev->first_parent_only && !rev->combine_merges) {
 385                         /* No "--first-parent", "-c", nor "--cc" */
 386                         rev->combine_merges = 1;
 387                         rev->dense_combined_merges = 1;
 388                 }
 389         }
 390         if (!rev->diffopt.output_format)
 391                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
 392 }
 393
 394 int cmd_show(int argc, const char **argv, const char *prefix)
 395 {
 396         struct rev_info rev;
 397         struct object_array_entry *objects;
 398         struct setup_revision_opt opt;
 399         int i, count, ret = 0;
 400
 401         git_config(git_log_config, NULL);
 402
 403         if (diff_use_color_default == -1)
 404                 diff_use_color_default = git_use_color_default;
 405
 406         init_revisions(&rev, prefix);
 407         rev.diff = 1;
 408         rev.always_show_header = 1;
 409         rev.no_walk = 1;
 410         memset(&opt, 0, sizeof(opt));
 411         opt.def = "HEAD";
 412         opt.tweak = show_rev_tweak_rev;
 413         cmd_log_init(argc, argv, prefix, &rev, &opt);
 414
 415         count = rev.pending.nr;
 416         objects = rev.pending.objects;
 417         for (i = 0; i < count && !ret; i++) {
 418                 struct object *o = objects[i].item;
 419                 const char *name = objects[i].name;
 420                 switch (o->type) {
 421                 case OBJ_BLOB:
 422                         ret = show_object(o->sha1, 0, NULL);
 423                         break;
 424                 case OBJ_TAG: {
 425                         struct tag *t = (struct tag *)o;
 426
 427                         if (rev.shown_one)
 428                                 putchar('\n');
 429                         printf("%stag %s%s\n",
 430                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 431                                         t->tag,
 432                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 433                         ret = show_object(o->sha1, 1, &rev);
 434                         rev.shown_one = 1;
 435                         if (ret)
 436                                 break;
 437                         o = parse_object(t->tagged->sha1);
 438                         if (!o)
 439                                 ret = error(_("Could not read object %s"),
 440                                             sha1_to_hex(t->tagged->sha1));
 441                         objects[i].item = o;
 442                         i--;
 443                         break;
 444                 }
 445                 case OBJ_TREE:
 446                         if (rev.shown_one)
 447                                 putchar('\n');
 448                         printf("%stree %s%s\n\n",
 449                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 450                                         name,
 451                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 452                         read_tree_recursive((struct tree *)o, "", 0, 0, NULL,
 453                                         show_tree_object, NULL);
 454                         rev.shown_one = 1;
 455                         break;
 456                 case OBJ_COMMIT:
 457                         rev.pending.nr = rev.pending.alloc = 0;
 458                         rev.pending.objects = NULL;
 459                         add_object_array(o, name, &rev.pending);
 460                         ret = cmd_log_walk(&rev);
 461                         break;
 462                 default:
 463                         ret = error(_("Unknown type: %d"), o->type);
 464                 }
 465         }
 466         free(objects);
 467         return ret;
 468 }
 469
 470 /*
 471  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
 472  */
 473 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
 474 {
 475         struct rev_info rev;
 476         struct setup_revision_opt opt;
 477
 478         git_config(git_log_config, NULL);
 479
 480         if (diff_use_color_default == -1)
 481                 diff_use_color_default = git_use_color_default;
 482
 483         init_revisions(&rev, prefix);
 484         init_reflog_walk(&rev.reflog_info);
 485         rev.abbrev_commit = 1;
 486         rev.verbose_header = 1;
 487         memset(&opt, 0, sizeof(opt));
 488         opt.def = "HEAD";
 489         cmd_log_init(argc, argv, prefix, &rev, &opt);
 490
 491         /*
 492          * This means that we override whatever commit format the user gave
 493          * on the cmd line.  Sad, but cmd_log_init() currently doesn't
 494          * allow us to set a different default.
 495          */
 496         rev.commit_format = CMIT_FMT_ONELINE;
 497         rev.use_terminator = 1;
 498         rev.always_show_header = 1;
 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.max_parents = 1;
1065         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
1066         rev.subject_prefix = fmt_patch_subject_prefix;
1067         memset(&s_r_opt, 0, sizeof(s_r_opt));
1068         s_r_opt.def = "HEAD";
1069
1070         if (default_attach) {
1071                 rev.mime_boundary = default_attach;
1072                 rev.no_inline = 1;
1073         }
1074
1075         /*
1076          * Parse the arguments before setup_revisions(), or something
1077          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1078          * possibly a valid SHA1.
1079          */
1080         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1081                              builtin_format_patch_usage,
1082                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1083                              PARSE_OPT_KEEP_DASHDASH);
1084
1085         if (do_signoff) {
1086                 const char *committer;
1087                 const char *endpos;
1088                 committer = git_committer_info(IDENT_ERROR_ON_NO_NAME);
1089                 endpos = strchr(committer, '>');
1090                 if (!endpos)
1091                         die(_("bogus committer info %s"), committer);
1092                 add_signoff = xmemdupz(committer, endpos - committer + 1);
1093         }
1094
1095         for (i = 0; i < extra_hdr.nr; i++) {
1096                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1097                 strbuf_addch(&buf, '\n');
1098         }
1099
1100         if (extra_to.nr)
1101                 strbuf_addstr(&buf, "To: ");
1102         for (i = 0; i < extra_to.nr; i++) {
1103                 if (i)
1104                         strbuf_addstr(&buf, "    ");
1105                 strbuf_addstr(&buf, extra_to.items[i].string);
1106                 if (i + 1 < extra_to.nr)
1107                         strbuf_addch(&buf, ',');
1108                 strbuf_addch(&buf, '\n');
1109         }
1110
1111         if (extra_cc.nr)
1112                 strbuf_addstr(&buf, "Cc: ");
1113         for (i = 0; i < extra_cc.nr; i++) {
1114                 if (i)
1115                         strbuf_addstr(&buf, "    ");
1116                 strbuf_addstr(&buf, extra_cc.items[i].string);
1117                 if (i + 1 < extra_cc.nr)
1118                         strbuf_addch(&buf, ',');
1119                 strbuf_addch(&buf, '\n');
1120         }
1121
1122         rev.extra_headers = strbuf_detach(&buf, NULL);
1123
1124         if (start_number < 0)
1125                 start_number = 1;
1126
1127         /*
1128          * If numbered is set solely due to format.numbered in config,
1129          * and it would conflict with --keep-subject (-k) from the
1130          * command line, reset "numbered".
1131          */
1132         if (numbered && keep_subject && !numbered_cmdline_opt)
1133                 numbered = 0;
1134
1135         if (numbered && keep_subject)
1136                 die (_("-n and -k are mutually exclusive."));
1137         if (keep_subject && subject_prefix)
1138                 die (_("--subject-prefix and -k are mutually exclusive."));
1139
1140         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1141         if (argc > 1)
1142                 die (_("unrecognized argument: %s"), argv[1]);
1143
1144         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1145                 die(_("--name-only does not make sense"));
1146         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1147                 die(_("--name-status does not make sense"));
1148         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1149                 die(_("--check does not make sense"));
1150
1151         if (!use_patch_format &&
1152                 (!rev.diffopt.output_format ||
1153                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1154                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1155
1156         /* Always generate a patch */
1157         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1158
1159         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1160                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1161
1162         if (rev.show_notes)
1163                 init_display_notes(&rev.notes_opt);
1164
1165         if (!use_stdout)
1166                 output_directory = set_outdir(prefix, output_directory);
1167         else
1168                 setup_pager();
1169
1170         if (output_directory) {
1171                 if (use_stdout)
1172                         die(_("standard output, or directory, which one?"));
1173                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1174                         die_errno(_("Could not create directory '%s'"),
1175                                   output_directory);
1176         }
1177
1178         if (rev.pending.nr == 1) {
1179                 if (rev.max_count < 0 && !rev.show_root_diff) {
1180                         /*
1181                          * This is traditional behaviour of "git format-patch
1182                          * origin" that prepares what the origin side still
1183                          * does not have.
1184                          */
1185                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1186                         add_head_to_pending(&rev);
1187                 }
1188                 /*
1189                  * Otherwise, it is "format-patch -22 HEAD", and/or
1190                  * "format-patch --root HEAD".  The user wants
1191                  * get_revision() to do the usual traversal.
1192                  */
1193         }
1194
1195         /*
1196          * We cannot move this anywhere earlier because we do want to
1197          * know if --root was given explicitly from the command line.
1198          */
1199         rev.show_root_diff = 1;
1200
1201         if (cover_letter) {
1202                 /* remember the range */
1203                 int i;
1204                 for (i = 0; i < rev.pending.nr; i++) {
1205                         struct object *o = rev.pending.objects[i].item;
1206                         if (!(o->flags & UNINTERESTING))
1207                                 head = (struct commit *)o;
1208                 }
1209                 /* We can't generate a cover letter without any patches */
1210                 if (!head)
1211                         return 0;
1212         }
1213
1214         if (ignore_if_in_upstream) {
1215                 /* Don't say anything if head and upstream are the same. */
1216                 if (rev.pending.nr == 2) {
1217                         struct object_array_entry *o = rev.pending.objects;
1218                         if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1219                                 return 0;
1220                 }
1221                 get_patch_ids(&rev, &ids, prefix);
1222         }
1223
1224         if (!use_stdout)
1225                 realstdout = xfdopen(xdup(1), "w");
1226
1227         if (prepare_revision_walk(&rev))
1228                 die(_("revision walk setup failed"));
1229         rev.boundary = 1;
1230         while ((commit = get_revision(&rev)) != NULL) {
1231                 if (commit->object.flags & BOUNDARY) {
1232                         boundary_count++;
1233                         origin = (boundary_count == 1) ? commit : NULL;
1234                         continue;
1235                 }
1236
1237                 if (ignore_if_in_upstream &&
1238                                 has_commit_patch_id(commit, &ids))
1239                         continue;
1240
1241                 nr++;
1242                 list = xrealloc(list, nr * sizeof(list[0]));
1243                 list[nr - 1] = commit;
1244         }
1245         total = nr;
1246         if (!keep_subject && auto_number && total > 1)
1247                 numbered = 1;
1248         if (numbered)
1249                 rev.total = total + start_number - 1;
1250         if (in_reply_to || thread || cover_letter)
1251                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1252         if (in_reply_to) {
1253                 const char *msgid = clean_message_id(in_reply_to);
1254                 string_list_append(rev.ref_message_ids, msgid);
1255         }
1256         rev.numbered_files = numbered_files;
1257         rev.patch_suffix = fmt_patch_suffix;
1258         if (cover_letter) {
1259                 if (thread)
1260                         gen_message_id(&rev, "cover");
1261                 make_cover_letter(&rev, use_stdout, numbered, numbered_files,
1262                                   origin, nr, list, head);
1263                 total++;
1264                 start_number--;
1265         }
1266         rev.add_signoff = add_signoff;
1267         while (0 <= --nr) {
1268                 int shown;
1269                 commit = list[nr];
1270                 rev.nr = total - nr + (start_number - 1);
1271                 /* Make the second and subsequent mails replies to the first */
1272                 if (thread) {
1273                         /* Have we already had a message ID? */
1274                         if (rev.message_id) {
1275                                 /*
1276                                  * For deep threading: make every mail
1277                                  * a reply to the previous one, no
1278                                  * matter what other options are set.
1279                                  *
1280                                  * For shallow threading:
1281                                  *
1282                                  * Without --cover-letter and
1283                                  * --in-reply-to, make every mail a
1284                                  * reply to the one before.
1285                                  *
1286                                  * With --in-reply-to but no
1287                                  * --cover-letter, make every mail a
1288                                  * reply to the <reply-to>.
1289                                  *
1290                                  * With --cover-letter, make every
1291                                  * mail but the cover letter a reply
1292                                  * to the cover letter.  The cover
1293                                  * letter is a reply to the
1294                                  * --in-reply-to, if specified.
1295                                  */
1296                                 if (thread == THREAD_SHALLOW
1297                                     && rev.ref_message_ids->nr > 0
1298                                     && (!cover_letter || rev.nr > 1))
1299                                         free(rev.message_id);
1300                                 else
1301                                         string_list_append(rev.ref_message_ids,
1302                                                            rev.message_id);
1303                         }
1304                         gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
1305                 }
1306
1307                 if (!use_stdout && reopen_stdout(numbered_files ? NULL : commit,
1308                                                  &rev))
1309                         die(_("Failed to create output files"));
1310                 shown = log_tree_commit(&rev, commit);
1311                 free(commit->buffer);
1312                 commit->buffer = NULL;
1313
1314                 /* We put one extra blank line between formatted
1315                  * patches and this flag is used by log-tree code
1316                  * to see if it needs to emit a LF before showing
1317                  * the log; when using one file per patch, we do
1318                  * not want the extra blank line.
1319                  */
1320                 if (!use_stdout)
1321                         rev.shown_one = 0;
1322                 if (shown) {
1323                         if (rev.mime_boundary)
1324                                 printf("\n--%s%s--\n\n\n",
1325                                        mime_boundary_leader,
1326                                        rev.mime_boundary);
1327                         else
1328                                 print_signature();
1329                 }
1330                 if (!use_stdout)
1331                         fclose(stdout);
1332         }
1333         free(list);
1334         string_list_clear(&extra_to, 0);
1335         string_list_clear(&extra_cc, 0);
1336         string_list_clear(&extra_hdr, 0);
1337         if (ignore_if_in_upstream)
1338                 free_patch_ids(&ids);
1339         return 0;
1340 }
1341
1342 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1343 {
1344         unsigned char sha1[20];
1345         if (get_sha1(arg, sha1) == 0) {
1346                 struct commit *commit = lookup_commit_reference(sha1);
1347                 if (commit) {
1348                         commit->object.flags |= flags;
1349                         add_pending_object(revs, &commit->object, arg);
1350                         return 0;
1351                 }
1352         }
1353         return -1;
1354 }
1355
1356 static const char * const cherry_usage[] = {
1357         "git cherry [-v] [<upstream> [<head> [<limit>]]]",
1358         NULL
1359 };
1360
1361 static void print_commit(char sign, struct commit *commit, int verbose,
1362                          int abbrev)
1363 {
1364         if (!verbose) {
1365                 printf("%c %s\n", sign,
1366                        find_unique_abbrev(commit->object.sha1, abbrev));
1367         } else {
1368                 struct strbuf buf = STRBUF_INIT;
1369                 struct pretty_print_context ctx = {0};
1370                 pretty_print_commit(CMIT_FMT_ONELINE, commit, &buf, &ctx);
1371                 printf("%c %s %s\n", sign,
1372                        find_unique_abbrev(commit->object.sha1, abbrev),
1373                        buf.buf);
1374                 strbuf_release(&buf);
1375         }
1376 }
1377
1378 int cmd_cherry(int argc, const char **argv, const char *prefix)
1379 {
1380         struct rev_info revs;
1381         struct patch_ids ids;
1382         struct commit *commit;
1383         struct commit_list *list = NULL;
1384         struct branch *current_branch;
1385         const char *upstream;
1386         const char *head = "HEAD";
1387         const char *limit = NULL;
1388         int verbose = 0, abbrev = 0;
1389
1390         struct option options[] = {
1391                 OPT__ABBREV(&abbrev),
1392                 OPT__VERBOSE(&verbose, "be verbose"),
1393                 OPT_END()
1394         };
1395
1396         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
1397
1398         switch (argc) {
1399         case 3:
1400                 limit = argv[2];
1401                 /* FALLTHROUGH */
1402         case 2:
1403                 head = argv[1];
1404                 /* FALLTHROUGH */
1405         case 1:
1406                 upstream = argv[0];
1407                 break;
1408         default:
1409                 current_branch = branch_get(NULL);
1410                 if (!current_branch || !current_branch->merge
1411                                         || !current_branch->merge[0]
1412                                         || !current_branch->merge[0]->dst) {
1413                         fprintf(stderr, _("Could not find a tracked"
1414                                         " remote branch, please"
1415                                         " specify <upstream> manually.\n"));
1416                         usage_with_options(cherry_usage, options);
1417                 }
1418
1419                 upstream = current_branch->merge[0]->dst;
1420         }
1421
1422         init_revisions(&revs, prefix);
1423         revs.diff = 1;
1424         revs.combine_merges = 0;
1425         revs.ignore_merges = 1;
1426         DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
1427
1428         if (add_pending_commit(head, &revs, 0))
1429                 die(_("Unknown commit %s"), head);
1430         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1431                 die(_("Unknown commit %s"), upstream);
1432
1433         /* Don't say anything if head and upstream are the same. */
1434         if (revs.pending.nr == 2) {
1435                 struct object_array_entry *o = revs.pending.objects;
1436                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1437                         return 0;
1438         }
1439
1440         get_patch_ids(&revs, &ids, prefix);
1441
1442         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1443                 die(_("Unknown commit %s"), limit);
1444
1445         /* reverse the list of commits */
1446         if (prepare_revision_walk(&revs))
1447                 die(_("revision walk setup failed"));
1448         while ((commit = get_revision(&revs)) != NULL) {
1449                 /* ignore merges */
1450                 if (commit->parents && commit->parents->next)
1451                         continue;
1452
1453                 commit_list_insert(commit, &list);
1454         }
1455
1456         while (list) {
1457                 char sign = '+';
1458
1459                 commit = list->item;
1460                 if (has_commit_patch_id(commit, &ids))
1461                         sign = '-';
1462                 print_commit(sign, commit, verbose, abbrev);
1463                 list = list->next;
1464         }
1465
1466         free_patch_ids(&ids);
1467         return 0;
1468 }