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_abbrev_commit;
  27 static int default_show_root = 1;
  28 static int decoration_style;
  29 static int decoration_given;
  30 static const char *fmt_patch_subject_prefix = "PATCH";
  31 static const char *fmt_pretty;
  32
  33 static const char * const builtin_log_usage[] = {
  34         "git log [<options>] [<since>..<until>] [[--] <path>...]\n"
  35         "   or: git show [options] <object>...",
  36         NULL
  37 };
  38
  39 static int parse_decoration_style(const char *var, const char *value)
  40 {
  41         switch (git_config_maybe_bool(var, value)) {
  42         case 1:
  43                 return DECORATE_SHORT_REFS;
  44         case 0:
  45                 return 0;
  46         default:
  47                 break;
  48         }
  49         if (!strcmp(value, "full"))
  50                 return DECORATE_FULL_REFS;
  51         else if (!strcmp(value, "short"))
  52                 return DECORATE_SHORT_REFS;
  53         return -1;
  54 }
  55
  56 static int decorate_callback(const struct option *opt, const char *arg, int unset)
  57 {
  58         if (unset)
  59                 decoration_style = 0;
  60         else if (arg)
  61                 decoration_style = parse_decoration_style("command line", arg);
  62         else
  63                 decoration_style = DECORATE_SHORT_REFS;
  64
  65         if (decoration_style < 0)
  66                 die("invalid --decorate option: %s", arg);
  67
  68         decoration_given = 1;
  69
  70         return 0;
  71 }
  72
  73 static void cmd_log_init_defaults(struct rev_info *rev)
  74 {
  75         rev->abbrev = DEFAULT_ABBREV;
  76         rev->commit_format = CMIT_FMT_DEFAULT;
  77         if (fmt_pretty)
  78                 get_commit_format(fmt_pretty, rev);
  79         rev->verbose_header = 1;
  80         DIFF_OPT_SET(&rev->diffopt, RECURSIVE);
  81         rev->abbrev_commit = default_abbrev_commit;
  82         rev->show_root_diff = default_show_root;
  83         rev->subject_prefix = fmt_patch_subject_prefix;
  84         DIFF_OPT_SET(&rev->diffopt, ALLOW_TEXTCONV);
  85
  86         if (default_date_mode)
  87                 rev->date_mode = parse_date_format(default_date_mode);
  88 }
  89
  90 static void cmd_log_init_finish(int argc, const char **argv, const char *prefix,
  91                          struct rev_info *rev, struct setup_revision_opt *opt)
  92 {
  93         struct userformat_want w;
  94         int quiet = 0, source = 0;
  95
  96         const struct option builtin_log_options[] = {
  97                 OPT_BOOLEAN(0, "quiet", &quiet, "suppress diff output"),
  98                 OPT_BOOLEAN(0, "source", &source, "show source"),
  99                 { OPTION_CALLBACK, 0, "decorate", NULL, NULL, "decorate options",
 100                   PARSE_OPT_OPTARG, decorate_callback},
 101                 OPT_END()
 102         };
 103
 104         argc = parse_options(argc, argv, prefix,
 105                              builtin_log_options, builtin_log_usage,
 106                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
 107                              PARSE_OPT_KEEP_DASHDASH);
 108
 109         argc = setup_revisions(argc, argv, rev, opt);
 110         if (quiet)
 111                 rev->diffopt.output_format |= DIFF_FORMAT_NO_OUTPUT;
 112
 113         /* Any arguments at this point are not recognized */
 114         if (argc > 1)
 115                 die("unrecognized argument: %s", argv[1]);
 116
 117         memset(&w, 0, sizeof(w));
 118         userformat_find_requirements(NULL, &w);
 119
 120         if (!rev->show_notes_given && (!rev->pretty_given || w.notes))
 121                 rev->show_notes = 1;
 122         if (rev->show_notes)
 123                 init_display_notes(&rev->notes_opt);
 124
 125         if (rev->diffopt.pickaxe || rev->diffopt.filter)
 126                 rev->always_show_header = 0;
 127         if (DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES)) {
 128                 rev->always_show_header = 0;
 129                 if (rev->diffopt.pathspec.nr != 1)
 130                         usage("git logs can only follow renames on one pathname at a time");
 131         }
 132
 133         if (source)
 134                 rev->show_source = 1;
 135
 136         if (rev->pretty_given && rev->commit_format == CMIT_FMT_RAW) {
 137                 /*
 138                  * "log --pretty=raw" is special; ignore UI oriented
 139                  * configuration variables such as decoration.
 140                  */
 141                 if (!decoration_given)
 142                         decoration_style = 0;
 143                 if (!rev->abbrev_commit_given)
 144                         rev->abbrev_commit = 0;
 145         }
 146
 147         if (decoration_style) {
 148                 rev->show_decorations = 1;
 149                 load_ref_decorations(decoration_style);
 150         }
 151         setup_pager();
 152 }
 153
 154 static void cmd_log_init(int argc, const char **argv, const char *prefix,
 155                          struct rev_info *rev, struct setup_revision_opt *opt)
 156 {
 157         cmd_log_init_defaults(rev);
 158         cmd_log_init_finish(argc, argv, prefix, rev, opt);
 159 }
 160
 161 /*
 162  * This gives a rough estimate for how many commits we
 163  * will print out in the list.
 164  */
 165 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
 166 {
 167         int n = 0;
 168
 169         while (list) {
 170                 struct commit *commit = list->item;
 171                 unsigned int flags = commit->object.flags;
 172                 list = list->next;
 173                 if (!(flags & (TREESAME | UNINTERESTING)))
 174                         n++;
 175         }
 176         return n;
 177 }
 178
 179 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
 180 {
 181         if (rev->shown_one) {
 182                 rev->shown_one = 0;
 183                 if (rev->commit_format != CMIT_FMT_ONELINE)
 184                         putchar(rev->diffopt.line_termination);
 185         }
 186         printf(_("Final output: %d %s\n"), nr, stage);
 187 }
 188
 189 static struct itimerval early_output_timer;
 190
 191 static void log_show_early(struct rev_info *revs, struct commit_list *list)
 192 {
 193         int i = revs->early_output;
 194         int show_header = 1;
 195
 196         sort_in_topological_order(&list, revs->lifo);
 197         while (list && i) {
 198                 struct commit *commit = list->item;
 199                 switch (simplify_commit(revs, commit)) {
 200                 case commit_show:
 201                         if (show_header) {
 202                                 int n = estimate_commit_count(revs, list);
 203                                 show_early_header(revs, "incomplete", n);
 204                                 show_header = 0;
 205                         }
 206                         log_tree_commit(revs, commit);
 207                         i--;
 208                         break;
 209                 case commit_ignore:
 210                         break;
 211                 case commit_error:
 212                         return;
 213                 }
 214                 list = list->next;
 215         }
 216
 217         /* Did we already get enough commits for the early output? */
 218         if (!i)
 219                 return;
 220
 221         /*
 222          * ..if no, then repeat it twice a second until we
 223          * do.
 224          *
 225          * NOTE! We don't use "it_interval", because if the
 226          * reader isn't listening, we want our output to be
 227          * throttled by the writing, and not have the timer
 228          * trigger every second even if we're blocked on a
 229          * reader!
 230          */
 231         early_output_timer.it_value.tv_sec = 0;
 232         early_output_timer.it_value.tv_usec = 500000;
 233         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 234 }
 235
 236 static void early_output(int signal)
 237 {
 238         show_early_output = log_show_early;
 239 }
 240
 241 static void setup_early_output(struct rev_info *rev)
 242 {
 243         struct sigaction sa;
 244
 245         /*
 246          * Set up the signal handler, minimally intrusively:
 247          * we only set a single volatile integer word (not
 248          * using sigatomic_t - trying to avoid unnecessary
 249          * system dependencies and headers), and using
 250          * SA_RESTART.
 251          */
 252         memset(&sa, 0, sizeof(sa));
 253         sa.sa_handler = early_output;
 254         sigemptyset(&sa.sa_mask);
 255         sa.sa_flags = SA_RESTART;
 256         sigaction(SIGALRM, &sa, NULL);
 257
 258         /*
 259          * If we can get the whole output in less than a
 260          * tenth of a second, don't even bother doing the
 261          * early-output thing..
 262          *
 263          * This is a one-time-only trigger.
 264          */
 265         early_output_timer.it_value.tv_sec = 0;
 266         early_output_timer.it_value.tv_usec = 100000;
 267         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 268 }
 269
 270 static void finish_early_output(struct rev_info *rev)
 271 {
 272         int n = estimate_commit_count(rev, rev->commits);
 273         signal(SIGALRM, SIG_IGN);
 274         show_early_header(rev, "done", n);
 275 }
 276
 277 static int cmd_log_walk(struct rev_info *rev)
 278 {
 279         struct commit *commit;
 280         int saved_nrl = 0;
 281         int saved_dcctc = 0;
 282
 283         if (rev->early_output)
 284                 setup_early_output(rev);
 285
 286         if (prepare_revision_walk(rev))
 287                 die(_("revision walk setup failed"));
 288
 289         if (rev->early_output)
 290                 finish_early_output(rev);
 291
 292         /*
 293          * For --check and --exit-code, the exit code is based on CHECK_FAILED
 294          * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
 295          * retain that state information if replacing rev->diffopt in this loop
 296          */
 297         while ((commit = get_revision(rev)) != NULL) {
 298                 if (!log_tree_commit(rev, commit) &&
 299                     rev->max_count >= 0)
 300                         /*
 301                          * We decremented max_count in get_revision,
 302                          * but we didn't actually show the commit.
 303                          */
 304                         rev->max_count++;
 305                 if (!rev->reflog_info) {
 306                         /* we allow cycles in reflog ancestry */
 307                         free(commit->buffer);
 308                         commit->buffer = NULL;
 309                 }
 310                 free_commit_list(commit->parents);
 311                 commit->parents = NULL;
 312                 if (saved_nrl < rev->diffopt.needed_rename_limit)
 313                         saved_nrl = rev->diffopt.needed_rename_limit;
 314                 if (rev->diffopt.degraded_cc_to_c)
 315                         saved_dcctc = 1;
 316         }
 317         rev->diffopt.degraded_cc_to_c = saved_dcctc;
 318         rev->diffopt.needed_rename_limit = saved_nrl;
 319
 320         if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
 321             DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
 322                 return 02;
 323         }
 324         return diff_result_code(&rev->diffopt, 0);
 325 }
 326
 327 static int git_log_config(const char *var, const char *value, void *cb)
 328 {
 329         if (!strcmp(var, "format.pretty"))
 330                 return git_config_string(&fmt_pretty, var, value);
 331         if (!strcmp(var, "format.subjectprefix"))
 332                 return git_config_string(&fmt_patch_subject_prefix, var, value);
 333         if (!strcmp(var, "log.abbrevcommit")) {
 334                 default_abbrev_commit = git_config_bool(var, value);
 335                 return 0;
 336         }
 337         if (!strcmp(var, "log.date"))
 338                 return git_config_string(&default_date_mode, var, value);
 339         if (!strcmp(var, "log.decorate")) {
 340                 decoration_style = parse_decoration_style(var, value);
 341                 if (decoration_style < 0)
 342                         decoration_style = 0; /* maybe warn? */
 343                 return 0;
 344         }
 345         if (!strcmp(var, "log.showroot")) {
 346                 default_show_root = git_config_bool(var, value);
 347                 return 0;
 348         }
 349         if (!prefixcmp(var, "color.decorate."))
 350                 return parse_decorate_color_config(var, 15, value);
 351
 352         return git_diff_ui_config(var, value, cb);
 353 }
 354
 355 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 356 {
 357         struct rev_info rev;
 358         struct setup_revision_opt opt;
 359
 360         git_config(git_log_config, NULL);
 361
 362         if (diff_use_color_default == -1)
 363                 diff_use_color_default = git_use_color_default;
 364
 365         init_revisions(&rev, prefix);
 366         rev.diff = 1;
 367         rev.simplify_history = 0;
 368         memset(&opt, 0, sizeof(opt));
 369         opt.def = "HEAD";
 370         cmd_log_init(argc, argv, prefix, &rev, &opt);
 371         if (!rev.diffopt.output_format)
 372                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
 373         return cmd_log_walk(&rev);
 374 }
 375
 376 static void show_tagger(char *buf, int len, struct rev_info *rev)
 377 {
 378         struct strbuf out = STRBUF_INIT;
 379         struct pretty_print_context pp = {0};
 380
 381         pp.fmt = rev->commit_format;
 382         pp.date_mode = rev->date_mode;
 383         pp_user_info(&pp, "Tagger", &out, buf, get_log_output_encoding());
 384         printf("%s", out.buf);
 385         strbuf_release(&out);
 386 }
 387
 388 static int show_object(const unsigned char *sha1, int show_tag_object,
 389         struct rev_info *rev)
 390 {
 391         unsigned long size;
 392         enum object_type type;
 393         char *buf = read_sha1_file(sha1, &type, &size);
 394         int offset = 0;
 395
 396         if (!buf)
 397                 return error(_("Could not read object %s"), sha1_to_hex(sha1));
 398
 399         if (show_tag_object)
 400                 while (offset < size && buf[offset] != '\n') {
 401                         int new_offset = offset + 1;
 402                         while (new_offset < size && buf[new_offset++] != '\n')
 403                                 ; /* do nothing */
 404                         if (!prefixcmp(buf + offset, "tagger "))
 405                                 show_tagger(buf + offset + 7,
 406                                             new_offset - offset - 7, rev);
 407                         offset = new_offset;
 408                 }
 409
 410         if (offset < size)
 411                 fwrite(buf + offset, size - offset, 1, stdout);
 412         free(buf);
 413         return 0;
 414 }
 415
 416 static int show_tree_object(const unsigned char *sha1,
 417                 const char *base, int baselen,
 418                 const char *pathname, unsigned mode, int stage, void *context)
 419 {
 420         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
 421         return 0;
 422 }
 423
 424 static void show_rev_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
 425 {
 426         if (rev->ignore_merges) {
 427                 /* There was no "-m" on the command line */
 428                 rev->ignore_merges = 0;
 429                 if (!rev->first_parent_only && !rev->combine_merges) {
 430                         /* No "--first-parent", "-c", nor "--cc" */
 431                         rev->combine_merges = 1;
 432                         rev->dense_combined_merges = 1;
 433                 }
 434         }
 435         if (!rev->diffopt.output_format)
 436                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
 437 }
 438
 439 int cmd_show(int argc, const char **argv, const char *prefix)
 440 {
 441         struct rev_info rev;
 442         struct object_array_entry *objects;
 443         struct setup_revision_opt opt;
 444         struct pathspec match_all;
 445         int i, count, ret = 0;
 446
 447         git_config(git_log_config, NULL);
 448
 449         if (diff_use_color_default == -1)
 450                 diff_use_color_default = git_use_color_default;
 451
 452         init_pathspec(&match_all, NULL);
 453         init_revisions(&rev, prefix);
 454         rev.diff = 1;
 455         rev.always_show_header = 1;
 456         rev.no_walk = 1;
 457         memset(&opt, 0, sizeof(opt));
 458         opt.def = "HEAD";
 459         opt.tweak = show_rev_tweak_rev;
 460         cmd_log_init(argc, argv, prefix, &rev, &opt);
 461
 462         count = rev.pending.nr;
 463         objects = rev.pending.objects;
 464         for (i = 0; i < count && !ret; i++) {
 465                 struct object *o = objects[i].item;
 466                 const char *name = objects[i].name;
 467                 switch (o->type) {
 468                 case OBJ_BLOB:
 469                         ret = show_object(o->sha1, 0, NULL);
 470                         break;
 471                 case OBJ_TAG: {
 472                         struct tag *t = (struct tag *)o;
 473
 474                         if (rev.shown_one)
 475                                 putchar('\n');
 476                         printf("%stag %s%s\n",
 477                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 478                                         t->tag,
 479                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 480                         ret = show_object(o->sha1, 1, &rev);
 481                         rev.shown_one = 1;
 482                         if (ret)
 483                                 break;
 484                         o = parse_object(t->tagged->sha1);
 485                         if (!o)
 486                                 ret = error(_("Could not read object %s"),
 487                                             sha1_to_hex(t->tagged->sha1));
 488                         objects[i].item = o;
 489                         i--;
 490                         break;
 491                 }
 492                 case OBJ_TREE:
 493                         if (rev.shown_one)
 494                                 putchar('\n');
 495                         printf("%stree %s%s\n\n",
 496                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 497                                         name,
 498                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 499                         read_tree_recursive((struct tree *)o, "", 0, 0, &match_all,
 500                                         show_tree_object, NULL);
 501                         rev.shown_one = 1;
 502                         break;
 503                 case OBJ_COMMIT:
 504                         rev.pending.nr = rev.pending.alloc = 0;
 505                         rev.pending.objects = NULL;
 506                         add_object_array(o, name, &rev.pending);
 507                         ret = cmd_log_walk(&rev);
 508                         break;
 509                 default:
 510                         ret = error(_("Unknown type: %d"), o->type);
 511                 }
 512         }
 513         free(objects);
 514         return ret;
 515 }
 516
 517 /*
 518  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
 519  */
 520 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
 521 {
 522         struct rev_info rev;
 523         struct setup_revision_opt opt;
 524
 525         git_config(git_log_config, NULL);
 526
 527         if (diff_use_color_default == -1)
 528                 diff_use_color_default = git_use_color_default;
 529
 530         init_revisions(&rev, prefix);
 531         init_reflog_walk(&rev.reflog_info);
 532         rev.verbose_header = 1;
 533         memset(&opt, 0, sizeof(opt));
 534         opt.def = "HEAD";
 535         cmd_log_init_defaults(&rev);
 536         rev.abbrev_commit = 1;
 537         rev.commit_format = CMIT_FMT_ONELINE;
 538         rev.use_terminator = 1;
 539         rev.always_show_header = 1;
 540         cmd_log_init_finish(argc, argv, prefix, &rev, &opt);
 541
 542         return cmd_log_walk(&rev);
 543 }
 544
 545 int cmd_log(int argc, const char **argv, const char *prefix)
 546 {
 547         struct rev_info rev;
 548         struct setup_revision_opt opt;
 549
 550         git_config(git_log_config, NULL);
 551
 552         if (diff_use_color_default == -1)
 553                 diff_use_color_default = git_use_color_default;
 554
 555         init_revisions(&rev, prefix);
 556         rev.always_show_header = 1;
 557         memset(&opt, 0, sizeof(opt));
 558         opt.def = "HEAD";
 559         cmd_log_init(argc, argv, prefix, &rev, &opt);
 560         return cmd_log_walk(&rev);
 561 }
 562
 563 /* format-patch */
 564
 565 static const char *fmt_patch_suffix = ".patch";
 566 static int numbered = 0;
 567 static int auto_number = 1;
 568
 569 static char *default_attach = NULL;
 570
 571 static struct string_list extra_hdr;
 572 static struct string_list extra_to;
 573 static struct string_list extra_cc;
 574
 575 static void add_header(const char *value)
 576 {
 577         struct string_list_item *item;
 578         int len = strlen(value);
 579         while (len && value[len - 1] == '\n')
 580                 len--;
 581
 582         if (!strncasecmp(value, "to: ", 4)) {
 583                 item = string_list_append(&extra_to, value + 4);
 584                 len -= 4;
 585         } else if (!strncasecmp(value, "cc: ", 4)) {
 586                 item = string_list_append(&extra_cc, value + 4);
 587                 len -= 4;
 588         } else {
 589                 item = string_list_append(&extra_hdr, value);
 590         }
 591
 592         item->string[len] = '\0';
 593 }
 594
 595 #define THREAD_SHALLOW 1
 596 #define THREAD_DEEP 2
 597 static int thread;
 598 static int do_signoff;
 599 static const char *signature = git_version_string;
 600
 601 static int git_format_config(const char *var, const char *value, void *cb)
 602 {
 603         if (!strcmp(var, "format.headers")) {
 604                 if (!value)
 605                         die(_("format.headers without value"));
 606                 add_header(value);
 607                 return 0;
 608         }
 609         if (!strcmp(var, "format.suffix"))
 610                 return git_config_string(&fmt_patch_suffix, var, value);
 611         if (!strcmp(var, "format.to")) {
 612                 if (!value)
 613                         return config_error_nonbool(var);
 614                 string_list_append(&extra_to, value);
 615                 return 0;
 616         }
 617         if (!strcmp(var, "format.cc")) {
 618                 if (!value)
 619                         return config_error_nonbool(var);
 620                 string_list_append(&extra_cc, value);
 621                 return 0;
 622         }
 623         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
 624                 return 0;
 625         }
 626         if (!strcmp(var, "format.numbered")) {
 627                 if (value && !strcasecmp(value, "auto")) {
 628                         auto_number = 1;
 629                         return 0;
 630                 }
 631                 numbered = git_config_bool(var, value);
 632                 auto_number = auto_number && numbered;
 633                 return 0;
 634         }
 635         if (!strcmp(var, "format.attach")) {
 636                 if (value && *value)
 637                         default_attach = xstrdup(value);
 638                 else
 639                         default_attach = xstrdup(git_version_string);
 640                 return 0;
 641         }
 642         if (!strcmp(var, "format.thread")) {
 643                 if (value && !strcasecmp(value, "deep")) {
 644                         thread = THREAD_DEEP;
 645                         return 0;
 646                 }
 647                 if (value && !strcasecmp(value, "shallow")) {
 648                         thread = THREAD_SHALLOW;
 649                         return 0;
 650                 }
 651                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
 652                 return 0;
 653         }
 654         if (!strcmp(var, "format.signoff")) {
 655                 do_signoff = git_config_bool(var, value);
 656                 return 0;
 657         }
 658         if (!strcmp(var, "format.signature"))
 659                 return git_config_string(&signature, var, value);
 660
 661         return git_log_config(var, value, cb);
 662 }
 663
 664 static FILE *realstdout = NULL;
 665 static const char *output_directory = NULL;
 666 static int outdir_offset;
 667
 668 static int reopen_stdout(struct commit *commit, struct rev_info *rev, int quiet)
 669 {
 670         struct strbuf filename = STRBUF_INIT;
 671         int suffix_len = strlen(fmt_patch_suffix) + 1;
 672
 673         if (output_directory) {
 674                 strbuf_addstr(&filename, output_directory);
 675                 if (filename.len >=
 676                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
 677                         return error(_("name of output directory is too long"));
 678                 if (filename.buf[filename.len - 1] != '/')
 679                         strbuf_addch(&filename, '/');
 680         }
 681
 682         get_patch_filename(commit, rev->nr, fmt_patch_suffix, &filename);
 683
 684         if (!quiet)
 685                 fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
 686
 687         if (freopen(filename.buf, "w", stdout) == NULL)
 688                 return error(_("Cannot open patch file %s"), filename.buf);
 689
 690         strbuf_release(&filename);
 691         return 0;
 692 }
 693
 694 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids, const char *prefix)
 695 {
 696         struct rev_info check_rev;
 697         struct commit *commit;
 698         struct object *o1, *o2;
 699         unsigned flags1, flags2;
 700
 701         if (rev->pending.nr != 2)
 702                 die(_("Need exactly one range."));
 703
 704         o1 = rev->pending.objects[0].item;
 705         flags1 = o1->flags;
 706         o2 = rev->pending.objects[1].item;
 707         flags2 = o2->flags;
 708
 709         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
 710                 die(_("Not a range."));
 711
 712         init_patch_ids(ids);
 713
 714         /* given a range a..b get all patch ids for b..a */
 715         init_revisions(&check_rev, prefix);
 716         o1->flags ^= UNINTERESTING;
 717         o2->flags ^= UNINTERESTING;
 718         add_pending_object(&check_rev, o1, "o1");
 719         add_pending_object(&check_rev, o2, "o2");
 720         if (prepare_revision_walk(&check_rev))
 721                 die(_("revision walk setup failed"));
 722
 723         while ((commit = get_revision(&check_rev)) != NULL) {
 724                 /* ignore merges */
 725                 if (commit->parents && commit->parents->next)
 726                         continue;
 727
 728                 add_commit_patch_id(commit, ids);
 729         }
 730
 731         /* reset for next revision walk */
 732         clear_commit_marks((struct commit *)o1,
 733                         SEEN | UNINTERESTING | SHOWN | ADDED);
 734         clear_commit_marks((struct commit *)o2,
 735                         SEEN | UNINTERESTING | SHOWN | ADDED);
 736         o1->flags = flags1;
 737         o2->flags = flags2;
 738 }
 739
 740 static void gen_message_id(struct rev_info *info, char *base)
 741 {
 742         const char *committer = git_committer_info(IDENT_WARN_ON_NO_NAME);
 743         const char *email_start = strrchr(committer, '<');
 744         const char *email_end = strrchr(committer, '>');
 745         struct strbuf buf = STRBUF_INIT;
 746         if (!email_start || !email_end || email_start > email_end - 1)
 747                 die(_("Could not extract email from committer identity."));
 748         strbuf_addf(&buf, "%s.%lu.git.%.*s", base,
 749                     (unsigned long) time(NULL),
 750                     (int)(email_end - email_start - 1), email_start + 1);
 751         info->message_id = strbuf_detach(&buf, NULL);
 752 }
 753
 754 static void print_signature(void)
 755 {
 756         if (signature && *signature)
 757                 printf("-- \n%s\n\n", signature);
 758 }
 759
 760 static void make_cover_letter(struct rev_info *rev, int use_stdout,
 761                               int numbered, int numbered_files,
 762                               struct commit *origin,
 763                               int nr, struct commit **list, struct commit *head,
 764                               int quiet)
 765 {
 766         const char *committer;
 767         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
 768         const char *msg;
 769         struct shortlog log;
 770         struct strbuf sb = STRBUF_INIT;
 771         int i;
 772         const char *encoding = "UTF-8";
 773         struct diff_options opts;
 774         int need_8bit_cte = 0;
 775         struct commit *commit = NULL;
 776         struct pretty_print_context pp = {0};
 777
 778         if (rev->commit_format != CMIT_FMT_EMAIL)
 779                 die(_("Cover letter needs email format"));
 780
 781         committer = git_committer_info(0);
 782
 783         if (!numbered_files) {
 784                 /*
 785                  * We fake a commit for the cover letter so we get the filename
 786                  * desired.
 787                  */
 788                 commit = xcalloc(1, sizeof(*commit));
 789                 commit->buffer = xmalloc(400);
 790                 snprintf(commit->buffer, 400,
 791                         "tree 0000000000000000000000000000000000000000\n"
 792                         "parent %s\n"
 793                         "author %s\n"
 794                         "committer %s\n\n"
 795                         "cover letter\n",
 796                         sha1_to_hex(head->object.sha1), committer, committer);
 797         }
 798
 799         if (!use_stdout && reopen_stdout(commit, rev, quiet))
 800                 return;
 801
 802         if (commit) {
 803
 804                 free(commit->buffer);
 805                 free(commit);
 806         }
 807
 808         log_write_email_headers(rev, head, &pp.subject, &pp.after_subject,
 809                                 &need_8bit_cte);
 810
 811         for (i = 0; !need_8bit_cte && i < nr; i++)
 812                 if (has_non_ascii(list[i]->buffer))
 813                         need_8bit_cte = 1;
 814
 815         msg = body;
 816         pp.fmt = CMIT_FMT_EMAIL;
 817         pp.date_mode = DATE_RFC2822;
 818         pp_user_info(&pp, NULL, &sb, committer, encoding);
 819         pp_title_line(&pp, &msg, &sb, encoding, need_8bit_cte);
 820         pp_remainder(&pp, &msg, &sb, 0);
 821         printf("%s\n", sb.buf);
 822
 823         strbuf_release(&sb);
 824
 825         shortlog_init(&log);
 826         log.wrap_lines = 1;
 827         log.wrap = 72;
 828         log.in1 = 2;
 829         log.in2 = 4;
 830         for (i = 0; i < nr; i++)
 831                 shortlog_add_commit(&log, list[i]);
 832
 833         shortlog_output(&log);
 834
 835         /*
 836          * We can only do diffstat with a unique reference point
 837          */
 838         if (!origin)
 839                 return;
 840
 841         memcpy(&opts, &rev->diffopt, sizeof(opts));
 842         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
 843
 844         diff_setup_done(&opts);
 845
 846         diff_tree_sha1(origin->tree->object.sha1,
 847                        head->tree->object.sha1,
 848                        "", &opts);
 849         diffcore_std(&opts);
 850         diff_flush(&opts);
 851
 852         printf("\n");
 853         print_signature();
 854 }
 855
 856 static const char *clean_message_id(const char *msg_id)
 857 {
 858         char ch;
 859         const char *a, *z, *m;
 860
 861         m = msg_id;
 862         while ((ch = *m) && (isspace(ch) || (ch == '<')))
 863                 m++;
 864         a = m;
 865         z = NULL;
 866         while ((ch = *m)) {
 867                 if (!isspace(ch) && (ch != '>'))
 868                         z = m;
 869                 m++;
 870         }
 871         if (!z)
 872                 die(_("insane in-reply-to: %s"), msg_id);
 873         if (++z == m)
 874                 return a;
 875         return xmemdupz(a, z - a);
 876 }
 877
 878 static const char *set_outdir(const char *prefix, const char *output_directory)
 879 {
 880         if (output_directory && is_absolute_path(output_directory))
 881                 return output_directory;
 882
 883         if (!prefix || !*prefix) {
 884                 if (output_directory)
 885                         return output_directory;
 886                 /* The user did not explicitly ask for "./" */
 887                 outdir_offset = 2;
 888                 return "./";
 889         }
 890
 891         outdir_offset = strlen(prefix);
 892         if (!output_directory)
 893                 return prefix;
 894
 895         return xstrdup(prefix_filename(prefix, outdir_offset,
 896                                        output_directory));
 897 }
 898
 899 static const char * const builtin_format_patch_usage[] = {
 900         "git format-patch [options] [<since> | <revision range>]",
 901         NULL
 902 };
 903
 904 static int keep_subject = 0;
 905
 906 static int keep_callback(const struct option *opt, const char *arg, int unset)
 907 {
 908         ((struct rev_info *)opt->value)->total = -1;
 909         keep_subject = 1;
 910         return 0;
 911 }
 912
 913 static int subject_prefix = 0;
 914
 915 static int subject_prefix_callback(const struct option *opt, const char *arg,
 916                             int unset)
 917 {
 918         subject_prefix = 1;
 919         ((struct rev_info *)opt->value)->subject_prefix = arg;
 920         return 0;
 921 }
 922
 923 static int numbered_cmdline_opt = 0;
 924
 925 static int numbered_callback(const struct option *opt, const char *arg,
 926                              int unset)
 927 {
 928         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
 929         if (unset)
 930                 auto_number =  0;
 931         return 0;
 932 }
 933
 934 static int no_numbered_callback(const struct option *opt, const char *arg,
 935                                 int unset)
 936 {
 937         return numbered_callback(opt, arg, 1);
 938 }
 939
 940 static int output_directory_callback(const struct option *opt, const char *arg,
 941                               int unset)
 942 {
 943         const char **dir = (const char **)opt->value;
 944         if (*dir)
 945                 die(_("Two output directories?"));
 946         *dir = arg;
 947         return 0;
 948 }
 949
 950 static int thread_callback(const struct option *opt, const char *arg, int unset)
 951 {
 952         int *thread = (int *)opt->value;
 953         if (unset)
 954                 *thread = 0;
 955         else if (!arg || !strcmp(arg, "shallow"))
 956                 *thread = THREAD_SHALLOW;
 957         else if (!strcmp(arg, "deep"))
 958                 *thread = THREAD_DEEP;
 959         else
 960                 return 1;
 961         return 0;
 962 }
 963
 964 static int attach_callback(const struct option *opt, const char *arg, int unset)
 965 {
 966         struct rev_info *rev = (struct rev_info *)opt->value;
 967         if (unset)
 968                 rev->mime_boundary = NULL;
 969         else if (arg)
 970                 rev->mime_boundary = arg;
 971         else
 972                 rev->mime_boundary = git_version_string;
 973         rev->no_inline = unset ? 0 : 1;
 974         return 0;
 975 }
 976
 977 static int inline_callback(const struct option *opt, const char *arg, int unset)
 978 {
 979         struct rev_info *rev = (struct rev_info *)opt->value;
 980         if (unset)
 981                 rev->mime_boundary = NULL;
 982         else if (arg)
 983                 rev->mime_boundary = arg;
 984         else
 985                 rev->mime_boundary = git_version_string;
 986         rev->no_inline = 0;
 987         return 0;
 988 }
 989
 990 static int header_callback(const struct option *opt, const char *arg, int unset)
 991 {
 992         if (unset) {
 993                 string_list_clear(&extra_hdr, 0);
 994                 string_list_clear(&extra_to, 0);
 995                 string_list_clear(&extra_cc, 0);
 996         } else {
 997             add_header(arg);
 998         }
 999         return 0;
1000 }
1001
1002 static int to_callback(const struct option *opt, const char *arg, int unset)
1003 {
1004         if (unset)
1005                 string_list_clear(&extra_to, 0);
1006         else
1007                 string_list_append(&extra_to, arg);
1008         return 0;
1009 }
1010
1011 static int cc_callback(const struct option *opt, const char *arg, int unset)
1012 {
1013         if (unset)
1014                 string_list_clear(&extra_cc, 0);
1015         else
1016                 string_list_append(&extra_cc, arg);
1017         return 0;
1018 }
1019
1020 int cmd_format_patch(int argc, const char **argv, const char *prefix)
1021 {
1022         struct commit *commit;
1023         struct commit **list = NULL;
1024         struct rev_info rev;
1025         struct setup_revision_opt s_r_opt;
1026         int nr = 0, total, i;
1027         int use_stdout = 0;
1028         int start_number = -1;
1029         int numbered_files = 0;         /* _just_ numbers */
1030         int ignore_if_in_upstream = 0;
1031         int cover_letter = 0;
1032         int boundary_count = 0;
1033         int no_binary_diff = 0;
1034         struct commit *origin = NULL, *head = NULL;
1035         const char *in_reply_to = NULL;
1036         struct patch_ids ids;
1037         char *add_signoff = NULL;
1038         struct strbuf buf = STRBUF_INIT;
1039         int use_patch_format = 0;
1040         int quiet = 0;
1041         const struct option builtin_format_patch_options[] = {
1042                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
1043                             "use [PATCH n/m] even with a single patch",
1044                             PARSE_OPT_NOARG, numbered_callback },
1045                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
1046                             "use [PATCH] even with multiple patches",
1047                             PARSE_OPT_NOARG, no_numbered_callback },
1048                 OPT_BOOLEAN('s', "signoff", &do_signoff, "add Signed-off-by:"),
1049                 OPT_BOOLEAN(0, "stdout", &use_stdout,
1050                             "print patches to standard out"),
1051                 OPT_BOOLEAN(0, "cover-letter", &cover_letter,
1052                             "generate a cover letter"),
1053                 OPT_BOOLEAN(0, "numbered-files", &numbered_files,
1054                             "use simple number sequence for output file names"),
1055                 OPT_STRING(0, "suffix", &fmt_patch_suffix, "sfx",
1056                             "use <sfx> instead of '.patch'"),
1057                 OPT_INTEGER(0, "start-number", &start_number,
1058                             "start numbering patches at <n> instead of 1"),
1059                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, "prefix",
1060                             "Use [<prefix>] instead of [PATCH]",
1061                             PARSE_OPT_NONEG, subject_prefix_callback },
1062                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
1063                             "dir", "store resulting files in <dir>",
1064                             PARSE_OPT_NONEG, output_directory_callback },
1065                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
1066                             "don't strip/add [PATCH]",
1067                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
1068                 OPT_BOOLEAN(0, "no-binary", &no_binary_diff,
1069                             "don't output binary diffs"),
1070                 OPT_BOOLEAN(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
1071                             "don't include a patch matching a commit upstream"),
1072                 { OPTION_BOOLEAN, 'p', "no-stat", &use_patch_format, NULL,
1073                   "show patch format instead of default (patch + stat)",
1074                   PARSE_OPT_NONEG | PARSE_OPT_NOARG },
1075                 OPT_GROUP("Messaging"),
1076                 { OPTION_CALLBACK, 0, "add-header", NULL, "header",
1077                             "add email header", 0, header_callback },
1078                 { OPTION_CALLBACK, 0, "to", NULL, "email", "add To: header",
1079                             0, to_callback },
1080                 { OPTION_CALLBACK, 0, "cc", NULL, "email", "add Cc: header",
1081                             0, cc_callback },
1082                 OPT_STRING(0, "in-reply-to", &in_reply_to, "message-id",
1083                             "make first mail a reply to <message-id>"),
1084                 { OPTION_CALLBACK, 0, "attach", &rev, "boundary",
1085                             "attach the patch", PARSE_OPT_OPTARG,
1086                             attach_callback },
1087                 { OPTION_CALLBACK, 0, "inline", &rev, "boundary",
1088                             "inline the patch",
1089                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
1090                             inline_callback },
1091                 { OPTION_CALLBACK, 0, "thread", &thread, "style",
1092                             "enable message threading, styles: shallow, deep",
1093                             PARSE_OPT_OPTARG, thread_callback },
1094                 OPT_STRING(0, "signature", &signature, "signature",
1095                             "add a signature"),
1096                 OPT_BOOLEAN(0, "quiet", &quiet,
1097                             "don't print the patch filenames"),
1098                 OPT_END()
1099         };
1100
1101         extra_hdr.strdup_strings = 1;
1102         extra_to.strdup_strings = 1;
1103         extra_cc.strdup_strings = 1;
1104         git_config(git_format_config, NULL);
1105         init_revisions(&rev, prefix);
1106         rev.commit_format = CMIT_FMT_EMAIL;
1107         rev.verbose_header = 1;
1108         rev.diff = 1;
1109         rev.max_parents = 1;
1110         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
1111         rev.subject_prefix = fmt_patch_subject_prefix;
1112         memset(&s_r_opt, 0, sizeof(s_r_opt));
1113         s_r_opt.def = "HEAD";
1114
1115         if (default_attach) {
1116                 rev.mime_boundary = default_attach;
1117                 rev.no_inline = 1;
1118         }
1119
1120         /*
1121          * Parse the arguments before setup_revisions(), or something
1122          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1123          * possibly a valid SHA1.
1124          */
1125         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1126                              builtin_format_patch_usage,
1127                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1128                              PARSE_OPT_KEEP_DASHDASH);
1129
1130         if (do_signoff) {
1131                 const char *committer;
1132                 const char *endpos;
1133                 committer = git_committer_info(IDENT_ERROR_ON_NO_NAME);
1134                 endpos = strchr(committer, '>');
1135                 if (!endpos)
1136                         die(_("bogus committer info %s"), committer);
1137                 add_signoff = xmemdupz(committer, endpos - committer + 1);
1138         }
1139
1140         for (i = 0; i < extra_hdr.nr; i++) {
1141                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1142                 strbuf_addch(&buf, '\n');
1143         }
1144
1145         if (extra_to.nr)
1146                 strbuf_addstr(&buf, "To: ");
1147         for (i = 0; i < extra_to.nr; i++) {
1148                 if (i)
1149                         strbuf_addstr(&buf, "    ");
1150                 strbuf_addstr(&buf, extra_to.items[i].string);
1151                 if (i + 1 < extra_to.nr)
1152                         strbuf_addch(&buf, ',');
1153                 strbuf_addch(&buf, '\n');
1154         }
1155
1156         if (extra_cc.nr)
1157                 strbuf_addstr(&buf, "Cc: ");
1158         for (i = 0; i < extra_cc.nr; i++) {
1159                 if (i)
1160                         strbuf_addstr(&buf, "    ");
1161                 strbuf_addstr(&buf, extra_cc.items[i].string);
1162                 if (i + 1 < extra_cc.nr)
1163                         strbuf_addch(&buf, ',');
1164                 strbuf_addch(&buf, '\n');
1165         }
1166
1167         rev.extra_headers = strbuf_detach(&buf, NULL);
1168
1169         if (start_number < 0)
1170                 start_number = 1;
1171
1172         /*
1173          * If numbered is set solely due to format.numbered in config,
1174          * and it would conflict with --keep-subject (-k) from the
1175          * command line, reset "numbered".
1176          */
1177         if (numbered && keep_subject && !numbered_cmdline_opt)
1178                 numbered = 0;
1179
1180         if (numbered && keep_subject)
1181                 die (_("-n and -k are mutually exclusive."));
1182         if (keep_subject && subject_prefix)
1183                 die (_("--subject-prefix and -k are mutually exclusive."));
1184         rev.preserve_subject = keep_subject;
1185
1186         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1187         if (argc > 1)
1188                 die (_("unrecognized argument: %s"), argv[1]);
1189
1190         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1191                 die(_("--name-only does not make sense"));
1192         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1193                 die(_("--name-status does not make sense"));
1194         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1195                 die(_("--check does not make sense"));
1196
1197         if (!use_patch_format &&
1198                 (!rev.diffopt.output_format ||
1199                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1200                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1201
1202         /* Always generate a patch */
1203         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1204
1205         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1206                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1207
1208         if (rev.show_notes)
1209                 init_display_notes(&rev.notes_opt);
1210
1211         if (!use_stdout)
1212                 output_directory = set_outdir(prefix, output_directory);
1213         else
1214                 setup_pager();
1215
1216         if (output_directory) {
1217                 if (use_stdout)
1218                         die(_("standard output, or directory, which one?"));
1219                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1220                         die_errno(_("Could not create directory '%s'"),
1221                                   output_directory);
1222         }
1223
1224         if (rev.pending.nr == 1) {
1225                 if (rev.max_count < 0 && !rev.show_root_diff) {
1226                         /*
1227                          * This is traditional behaviour of "git format-patch
1228                          * origin" that prepares what the origin side still
1229                          * does not have.
1230                          */
1231                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1232                         add_head_to_pending(&rev);
1233                 }
1234                 /*
1235                  * Otherwise, it is "format-patch -22 HEAD", and/or
1236                  * "format-patch --root HEAD".  The user wants
1237                  * get_revision() to do the usual traversal.
1238                  */
1239         }
1240
1241         /*
1242          * We cannot move this anywhere earlier because we do want to
1243          * know if --root was given explicitly from the command line.
1244          */
1245         rev.show_root_diff = 1;
1246
1247         if (cover_letter) {
1248                 /* remember the range */
1249                 int i;
1250                 for (i = 0; i < rev.pending.nr; i++) {
1251                         struct object *o = rev.pending.objects[i].item;
1252                         if (!(o->flags & UNINTERESTING))
1253                                 head = (struct commit *)o;
1254                 }
1255                 /* We can't generate a cover letter without any patches */
1256                 if (!head)
1257                         return 0;
1258         }
1259
1260         if (ignore_if_in_upstream) {
1261                 /* Don't say anything if head and upstream are the same. */
1262                 if (rev.pending.nr == 2) {
1263                         struct object_array_entry *o = rev.pending.objects;
1264                         if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1265                                 return 0;
1266                 }
1267                 get_patch_ids(&rev, &ids, prefix);
1268         }
1269
1270         if (!use_stdout)
1271                 realstdout = xfdopen(xdup(1), "w");
1272
1273         if (prepare_revision_walk(&rev))
1274                 die(_("revision walk setup failed"));
1275         rev.boundary = 1;
1276         while ((commit = get_revision(&rev)) != NULL) {
1277                 if (commit->object.flags & BOUNDARY) {
1278                         boundary_count++;
1279                         origin = (boundary_count == 1) ? commit : NULL;
1280                         continue;
1281                 }
1282
1283                 if (ignore_if_in_upstream &&
1284                                 has_commit_patch_id(commit, &ids))
1285                         continue;
1286
1287                 nr++;
1288                 list = xrealloc(list, nr * sizeof(list[0]));
1289                 list[nr - 1] = commit;
1290         }
1291         total = nr;
1292         if (!keep_subject && auto_number && total > 1)
1293                 numbered = 1;
1294         if (numbered)
1295                 rev.total = total + start_number - 1;
1296         if (in_reply_to || thread || cover_letter)
1297                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1298         if (in_reply_to) {
1299                 const char *msgid = clean_message_id(in_reply_to);
1300                 string_list_append(rev.ref_message_ids, msgid);
1301         }
1302         rev.numbered_files = numbered_files;
1303         rev.patch_suffix = fmt_patch_suffix;
1304         if (cover_letter) {
1305                 if (thread)
1306                         gen_message_id(&rev, "cover");
1307                 make_cover_letter(&rev, use_stdout, numbered, numbered_files,
1308                                   origin, nr, list, head, quiet);
1309                 total++;
1310                 start_number--;
1311         }
1312         rev.add_signoff = add_signoff;
1313         while (0 <= --nr) {
1314                 int shown;
1315                 commit = list[nr];
1316                 rev.nr = total - nr + (start_number - 1);
1317                 /* Make the second and subsequent mails replies to the first */
1318                 if (thread) {
1319                         /* Have we already had a message ID? */
1320                         if (rev.message_id) {
1321                                 /*
1322                                  * For deep threading: make every mail
1323                                  * a reply to the previous one, no
1324                                  * matter what other options are set.
1325                                  *
1326                                  * For shallow threading:
1327                                  *
1328                                  * Without --cover-letter and
1329                                  * --in-reply-to, make every mail a
1330                                  * reply to the one before.
1331                                  *
1332                                  * With --in-reply-to but no
1333                                  * --cover-letter, make every mail a
1334                                  * reply to the <reply-to>.
1335                                  *
1336                                  * With --cover-letter, make every
1337                                  * mail but the cover letter a reply
1338                                  * to the cover letter.  The cover
1339                                  * letter is a reply to the
1340                                  * --in-reply-to, if specified.
1341                                  */
1342                                 if (thread == THREAD_SHALLOW
1343                                     && rev.ref_message_ids->nr > 0
1344                                     && (!cover_letter || rev.nr > 1))
1345                                         free(rev.message_id);
1346                                 else
1347                                         string_list_append(rev.ref_message_ids,
1348                                                            rev.message_id);
1349                         }
1350                         gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
1351                 }
1352
1353                 if (!use_stdout && reopen_stdout(numbered_files ? NULL : commit,
1354                                                  &rev, quiet))
1355                         die(_("Failed to create output files"));
1356                 shown = log_tree_commit(&rev, commit);
1357                 free(commit->buffer);
1358                 commit->buffer = NULL;
1359
1360                 /* We put one extra blank line between formatted
1361                  * patches and this flag is used by log-tree code
1362                  * to see if it needs to emit a LF before showing
1363                  * the log; when using one file per patch, we do
1364                  * not want the extra blank line.
1365                  */
1366                 if (!use_stdout)
1367                         rev.shown_one = 0;
1368                 if (shown) {
1369                         if (rev.mime_boundary)
1370                                 printf("\n--%s%s--\n\n\n",
1371                                        mime_boundary_leader,
1372                                        rev.mime_boundary);
1373                         else
1374                                 print_signature();
1375                 }
1376                 if (!use_stdout)
1377                         fclose(stdout);
1378         }
1379         free(list);
1380         string_list_clear(&extra_to, 0);
1381         string_list_clear(&extra_cc, 0);
1382         string_list_clear(&extra_hdr, 0);
1383         if (ignore_if_in_upstream)
1384                 free_patch_ids(&ids);
1385         return 0;
1386 }
1387
1388 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1389 {
1390         unsigned char sha1[20];
1391         if (get_sha1(arg, sha1) == 0) {
1392                 struct commit *commit = lookup_commit_reference(sha1);
1393                 if (commit) {
1394                         commit->object.flags |= flags;
1395                         add_pending_object(revs, &commit->object, arg);
1396                         return 0;
1397                 }
1398         }
1399         return -1;
1400 }
1401
1402 static const char * const cherry_usage[] = {
1403         "git cherry [-v] [<upstream> [<head> [<limit>]]]",
1404         NULL
1405 };
1406
1407 static void print_commit(char sign, struct commit *commit, int verbose,
1408                          int abbrev)
1409 {
1410         if (!verbose) {
1411                 printf("%c %s\n", sign,
1412                        find_unique_abbrev(commit->object.sha1, abbrev));
1413         } else {
1414                 struct strbuf buf = STRBUF_INIT;
1415                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
1416                 printf("%c %s %s\n", sign,
1417                        find_unique_abbrev(commit->object.sha1, abbrev),
1418                        buf.buf);
1419                 strbuf_release(&buf);
1420         }
1421 }
1422
1423 int cmd_cherry(int argc, const char **argv, const char *prefix)
1424 {
1425         struct rev_info revs;
1426         struct patch_ids ids;
1427         struct commit *commit;
1428         struct commit_list *list = NULL;
1429         struct branch *current_branch;
1430         const char *upstream;
1431         const char *head = "HEAD";
1432         const char *limit = NULL;
1433         int verbose = 0, abbrev = 0;
1434
1435         struct option options[] = {
1436                 OPT__ABBREV(&abbrev),
1437                 OPT__VERBOSE(&verbose, "be verbose"),
1438                 OPT_END()
1439         };
1440
1441         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
1442
1443         switch (argc) {
1444         case 3:
1445                 limit = argv[2];
1446                 /* FALLTHROUGH */
1447         case 2:
1448                 head = argv[1];
1449                 /* FALLTHROUGH */
1450         case 1:
1451                 upstream = argv[0];
1452                 break;
1453         default:
1454                 current_branch = branch_get(NULL);
1455                 if (!current_branch || !current_branch->merge
1456                                         || !current_branch->merge[0]
1457                                         || !current_branch->merge[0]->dst) {
1458                         fprintf(stderr, _("Could not find a tracked"
1459                                         " remote branch, please"
1460                                         " specify <upstream> manually.\n"));
1461                         usage_with_options(cherry_usage, options);
1462                 }
1463
1464                 upstream = current_branch->merge[0]->dst;
1465         }
1466
1467         init_revisions(&revs, prefix);
1468         revs.diff = 1;
1469         revs.combine_merges = 0;
1470         revs.ignore_merges = 1;
1471         DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
1472
1473         if (add_pending_commit(head, &revs, 0))
1474                 die(_("Unknown commit %s"), head);
1475         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1476                 die(_("Unknown commit %s"), upstream);
1477
1478         /* Don't say anything if head and upstream are the same. */
1479         if (revs.pending.nr == 2) {
1480                 struct object_array_entry *o = revs.pending.objects;
1481                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1482                         return 0;
1483         }
1484
1485         get_patch_ids(&revs, &ids, prefix);
1486
1487         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1488                 die(_("Unknown commit %s"), limit);
1489
1490         /* reverse the list of commits */
1491         if (prepare_revision_walk(&revs))
1492                 die(_("revision walk setup failed"));
1493         while ((commit = get_revision(&revs)) != NULL) {
1494                 /* ignore merges */
1495                 if (commit->parents && commit->parents->next)
1496                         continue;
1497
1498                 commit_list_insert(commit, &list);
1499         }
1500
1501         while (list) {
1502                 char sign = '+';
1503
1504                 commit = list->item;
1505                 if (has_commit_patch_id(commit, &ids))
1506                         sign = '-';
1507                 print_commit(sign, commit, verbose, abbrev);
1508                 list = list->next;
1509         }
1510
1511         free_patch_ids(&ids);
1512         return 0;
1513 }