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 #include "branch.h"
  23 #include "streaming.h"
  24
  25 /* Set a default date-time format for git log ("log.date" config variable) */
  26 static const char *default_date_mode = NULL;
  27
  28 static int default_abbrev_commit;
  29 static int default_show_root = 1;
  30 static int decoration_style;
  31 static int decoration_given;
  32 static const char *fmt_patch_subject_prefix = "PATCH";
  33 static const char *fmt_pretty;
  34
  35 static const char * const builtin_log_usage[] = {
  36         "git log [<options>] [<since>..<until>] [[--] <path>...]\n"
  37         "   or: git show [options] <object>...",
  38         NULL
  39 };
  40
  41 static int parse_decoration_style(const char *var, const char *value)
  42 {
  43         switch (git_config_maybe_bool(var, value)) {
  44         case 1:
  45                 return DECORATE_SHORT_REFS;
  46         case 0:
  47                 return 0;
  48         default:
  49                 break;
  50         }
  51         if (!strcmp(value, "full"))
  52                 return DECORATE_FULL_REFS;
  53         else if (!strcmp(value, "short"))
  54                 return DECORATE_SHORT_REFS;
  55         return -1;
  56 }
  57
  58 static int decorate_callback(const struct option *opt, const char *arg, int unset)
  59 {
  60         if (unset)
  61                 decoration_style = 0;
  62         else if (arg)
  63                 decoration_style = parse_decoration_style("command line", arg);
  64         else
  65                 decoration_style = DECORATE_SHORT_REFS;
  66
  67         if (decoration_style < 0)
  68                 die("invalid --decorate option: %s", arg);
  69
  70         decoration_given = 1;
  71
  72         return 0;
  73 }
  74
  75 static void cmd_log_init_defaults(struct rev_info *rev)
  76 {
  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->diffopt.stat_width = -1; /* use full terminal width */
  82         rev->diffopt.stat_graph_width = -1; /* respect statGraphWidth config */
  83         rev->abbrev_commit = default_abbrev_commit;
  84         rev->show_root_diff = default_show_root;
  85         rev->subject_prefix = fmt_patch_subject_prefix;
  86         DIFF_OPT_SET(&rev->diffopt, ALLOW_TEXTCONV);
  87
  88         if (default_date_mode)
  89                 rev->date_mode = parse_date_format(default_date_mode);
  90 }
  91
  92 static void cmd_log_init_finish(int argc, const char **argv, const char *prefix,
  93                          struct rev_info *rev, struct setup_revision_opt *opt)
  94 {
  95         struct userformat_want w;
  96         int quiet = 0, source = 0;
  97
  98         const struct option builtin_log_options[] = {
  99                 OPT_BOOLEAN(0, "quiet", &quiet, "suppress diff output"),
 100                 OPT_BOOLEAN(0, "source", &source, "show source"),
 101                 { OPTION_CALLBACK, 0, "decorate", NULL, NULL, "decorate options",
 102                   PARSE_OPT_OPTARG, decorate_callback},
 103                 OPT_END()
 104         };
 105
 106         argc = parse_options(argc, argv, prefix,
 107                              builtin_log_options, builtin_log_usage,
 108                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
 109                              PARSE_OPT_KEEP_DASHDASH);
 110
 111         argc = setup_revisions(argc, argv, rev, opt);
 112         if (quiet)
 113                 rev->diffopt.output_format |= DIFF_FORMAT_NO_OUTPUT;
 114
 115         /* Any arguments at this point are not recognized */
 116         if (argc > 1)
 117                 die("unrecognized argument: %s", argv[1]);
 118
 119         memset(&w, 0, sizeof(w));
 120         userformat_find_requirements(NULL, &w);
 121
 122         if (!rev->show_notes_given && (!rev->pretty_given || w.notes))
 123                 rev->show_notes = 1;
 124         if (rev->show_notes)
 125                 init_display_notes(&rev->notes_opt);
 126
 127         if (rev->diffopt.pickaxe || rev->diffopt.filter)
 128                 rev->always_show_header = 0;
 129         if (DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES)) {
 130                 rev->always_show_header = 0;
 131                 if (rev->diffopt.pathspec.nr != 1)
 132                         usage("git logs can only follow renames on one pathname at a time");
 133         }
 134
 135         if (source)
 136                 rev->show_source = 1;
 137
 138         if (rev->pretty_given && rev->commit_format == CMIT_FMT_RAW) {
 139                 /*
 140                  * "log --pretty=raw" is special; ignore UI oriented
 141                  * configuration variables such as decoration.
 142                  */
 143                 if (!decoration_given)
 144                         decoration_style = 0;
 145                 if (!rev->abbrev_commit_given)
 146                         rev->abbrev_commit = 0;
 147         }
 148
 149         if (decoration_style) {
 150                 rev->show_decorations = 1;
 151                 load_ref_decorations(decoration_style);
 152         }
 153         setup_pager();
 154 }
 155
 156 static void cmd_log_init(int argc, const char **argv, const char *prefix,
 157                          struct rev_info *rev, struct setup_revision_opt *opt)
 158 {
 159         cmd_log_init_defaults(rev);
 160         cmd_log_init_finish(argc, argv, prefix, rev, opt);
 161 }
 162
 163 /*
 164  * This gives a rough estimate for how many commits we
 165  * will print out in the list.
 166  */
 167 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
 168 {
 169         int n = 0;
 170
 171         while (list) {
 172                 struct commit *commit = list->item;
 173                 unsigned int flags = commit->object.flags;
 174                 list = list->next;
 175                 if (!(flags & (TREESAME | UNINTERESTING)))
 176                         n++;
 177         }
 178         return n;
 179 }
 180
 181 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
 182 {
 183         if (rev->shown_one) {
 184                 rev->shown_one = 0;
 185                 if (rev->commit_format != CMIT_FMT_ONELINE)
 186                         putchar(rev->diffopt.line_termination);
 187         }
 188         printf(_("Final output: %d %s\n"), nr, stage);
 189 }
 190
 191 static struct itimerval early_output_timer;
 192
 193 static void log_show_early(struct rev_info *revs, struct commit_list *list)
 194 {
 195         int i = revs->early_output;
 196         int show_header = 1;
 197
 198         sort_in_topological_order(&list, revs->lifo);
 199         while (list && i) {
 200                 struct commit *commit = list->item;
 201                 switch (simplify_commit(revs, commit)) {
 202                 case commit_show:
 203                         if (show_header) {
 204                                 int n = estimate_commit_count(revs, list);
 205                                 show_early_header(revs, "incomplete", n);
 206                                 show_header = 0;
 207                         }
 208                         log_tree_commit(revs, commit);
 209                         i--;
 210                         break;
 211                 case commit_ignore:
 212                         break;
 213                 case commit_error:
 214                         return;
 215                 }
 216                 list = list->next;
 217         }
 218
 219         /* Did we already get enough commits for the early output? */
 220         if (!i)
 221                 return;
 222
 223         /*
 224          * ..if no, then repeat it twice a second until we
 225          * do.
 226          *
 227          * NOTE! We don't use "it_interval", because if the
 228          * reader isn't listening, we want our output to be
 229          * throttled by the writing, and not have the timer
 230          * trigger every second even if we're blocked on a
 231          * reader!
 232          */
 233         early_output_timer.it_value.tv_sec = 0;
 234         early_output_timer.it_value.tv_usec = 500000;
 235         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 236 }
 237
 238 static void early_output(int signal)
 239 {
 240         show_early_output = log_show_early;
 241 }
 242
 243 static void setup_early_output(struct rev_info *rev)
 244 {
 245         struct sigaction sa;
 246
 247         /*
 248          * Set up the signal handler, minimally intrusively:
 249          * we only set a single volatile integer word (not
 250          * using sigatomic_t - trying to avoid unnecessary
 251          * system dependencies and headers), and using
 252          * SA_RESTART.
 253          */
 254         memset(&sa, 0, sizeof(sa));
 255         sa.sa_handler = early_output;
 256         sigemptyset(&sa.sa_mask);
 257         sa.sa_flags = SA_RESTART;
 258         sigaction(SIGALRM, &sa, NULL);
 259
 260         /*
 261          * If we can get the whole output in less than a
 262          * tenth of a second, don't even bother doing the
 263          * early-output thing..
 264          *
 265          * This is a one-time-only trigger.
 266          */
 267         early_output_timer.it_value.tv_sec = 0;
 268         early_output_timer.it_value.tv_usec = 100000;
 269         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 270 }
 271
 272 static void finish_early_output(struct rev_info *rev)
 273 {
 274         int n = estimate_commit_count(rev, rev->commits);
 275         signal(SIGALRM, SIG_IGN);
 276         show_early_header(rev, "done", n);
 277 }
 278
 279 static int cmd_log_walk(struct rev_info *rev)
 280 {
 281         struct commit *commit;
 282         int saved_nrl = 0;
 283         int saved_dcctc = 0;
 284
 285         if (rev->early_output)
 286                 setup_early_output(rev);
 287
 288         if (prepare_revision_walk(rev))
 289                 die(_("revision walk setup failed"));
 290
 291         if (rev->early_output)
 292                 finish_early_output(rev);
 293
 294         /*
 295          * For --check and --exit-code, the exit code is based on CHECK_FAILED
 296          * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
 297          * retain that state information if replacing rev->diffopt in this loop
 298          */
 299         while ((commit = get_revision(rev)) != NULL) {
 300                 if (!log_tree_commit(rev, commit) &&
 301                     rev->max_count >= 0)
 302                         /*
 303                          * We decremented max_count in get_revision,
 304                          * but we didn't actually show the commit.
 305                          */
 306                         rev->max_count++;
 307                 if (!rev->reflog_info) {
 308                         /* we allow cycles in reflog ancestry */
 309                         free(commit->buffer);
 310                         commit->buffer = NULL;
 311                 }
 312                 free_commit_list(commit->parents);
 313                 commit->parents = NULL;
 314                 if (saved_nrl < rev->diffopt.needed_rename_limit)
 315                         saved_nrl = rev->diffopt.needed_rename_limit;
 316                 if (rev->diffopt.degraded_cc_to_c)
 317                         saved_dcctc = 1;
 318         }
 319         rev->diffopt.degraded_cc_to_c = saved_dcctc;
 320         rev->diffopt.needed_rename_limit = saved_nrl;
 321
 322         if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
 323             DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
 324                 return 02;
 325         }
 326         return diff_result_code(&rev->diffopt, 0);
 327 }
 328
 329 static int git_log_config(const char *var, const char *value, void *cb)
 330 {
 331         if (!strcmp(var, "format.pretty"))
 332                 return git_config_string(&fmt_pretty, var, value);
 333         if (!strcmp(var, "format.subjectprefix"))
 334                 return git_config_string(&fmt_patch_subject_prefix, var, value);
 335         if (!strcmp(var, "log.abbrevcommit")) {
 336                 default_abbrev_commit = git_config_bool(var, value);
 337                 return 0;
 338         }
 339         if (!strcmp(var, "log.date"))
 340                 return git_config_string(&default_date_mode, var, value);
 341         if (!strcmp(var, "log.decorate")) {
 342                 decoration_style = parse_decoration_style(var, value);
 343                 if (decoration_style < 0)
 344                         decoration_style = 0; /* maybe warn? */
 345                 return 0;
 346         }
 347         if (!strcmp(var, "log.showroot")) {
 348                 default_show_root = git_config_bool(var, value);
 349                 return 0;
 350         }
 351         if (!prefixcmp(var, "color.decorate."))
 352                 return parse_decorate_color_config(var, 15, value);
 353
 354         return git_diff_ui_config(var, value, cb);
 355 }
 356
 357 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 358 {
 359         struct rev_info rev;
 360         struct setup_revision_opt opt;
 361
 362         git_config(git_log_config, NULL);
 363
 364         init_revisions(&rev, prefix);
 365         rev.diff = 1;
 366         rev.simplify_history = 0;
 367         memset(&opt, 0, sizeof(opt));
 368         opt.def = "HEAD";
 369         cmd_log_init(argc, argv, prefix, &rev, &opt);
 370         if (!rev.diffopt.output_format)
 371                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
 372         return cmd_log_walk(&rev);
 373 }
 374
 375 static void show_tagger(char *buf, int len, struct rev_info *rev)
 376 {
 377         struct strbuf out = STRBUF_INIT;
 378         struct pretty_print_context pp = {0};
 379
 380         pp.fmt = rev->commit_format;
 381         pp.date_mode = rev->date_mode;
 382         pp_user_info(&pp, "Tagger", &out, buf, get_log_output_encoding());
 383         printf("%s", out.buf);
 384         strbuf_release(&out);
 385 }
 386
 387 static int show_blob_object(const unsigned char *sha1, struct rev_info *rev)
 388 {
 389         fflush(stdout);
 390         return stream_blob_to_fd(1, sha1, NULL, 0);
 391 }
 392
 393 static int show_tag_object(const unsigned char *sha1, struct rev_info *rev)
 394 {
 395         unsigned long size;
 396         enum object_type type;
 397         char *buf = read_sha1_file(sha1, &type, &size);
 398         int offset = 0;
 399
 400         if (!buf)
 401                 return error(_("Could not read object %s"), sha1_to_hex(sha1));
 402
 403         assert(type == OBJ_TAG);
 404         while (offset < size && buf[offset] != '\n') {
 405                 int new_offset = offset + 1;
 406                 while (new_offset < size && buf[new_offset++] != '\n')
 407                         ; /* do nothing */
 408                 if (!prefixcmp(buf + offset, "tagger "))
 409                         show_tagger(buf + offset + 7,
 410                                     new_offset - offset - 7, rev);
 411                 offset = new_offset;
 412         }
 413
 414         if (offset < size)
 415                 fwrite(buf + offset, size - offset, 1, stdout);
 416         free(buf);
 417         return 0;
 418 }
 419
 420 static int show_tree_object(const unsigned char *sha1,
 421                 const char *base, int baselen,
 422                 const char *pathname, unsigned mode, int stage, void *context)
 423 {
 424         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
 425         return 0;
 426 }
 427
 428 static void show_rev_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
 429 {
 430         if (rev->ignore_merges) {
 431                 /* There was no "-m" on the command line */
 432                 rev->ignore_merges = 0;
 433                 if (!rev->first_parent_only && !rev->combine_merges) {
 434                         /* No "--first-parent", "-c", nor "--cc" */
 435                         rev->combine_merges = 1;
 436                         rev->dense_combined_merges = 1;
 437                 }
 438         }
 439         if (!rev->diffopt.output_format)
 440                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
 441 }
 442
 443 int cmd_show(int argc, const char **argv, const char *prefix)
 444 {
 445         struct rev_info rev;
 446         struct object_array_entry *objects;
 447         struct setup_revision_opt opt;
 448         struct pathspec match_all;
 449         int i, count, ret = 0;
 450
 451         git_config(git_log_config, NULL);
 452
 453         init_pathspec(&match_all, NULL);
 454         init_revisions(&rev, prefix);
 455         rev.diff = 1;
 456         rev.always_show_header = 1;
 457         rev.no_walk = 1;
 458         rev.diffopt.stat_width = -1;    /* Scale to real terminal size */
 459
 460         memset(&opt, 0, sizeof(opt));
 461         opt.def = "HEAD";
 462         opt.tweak = show_rev_tweak_rev;
 463         cmd_log_init(argc, argv, prefix, &rev, &opt);
 464
 465         if (!rev.no_walk)
 466                 return cmd_log_walk(&rev);
 467
 468         count = rev.pending.nr;
 469         objects = rev.pending.objects;
 470         for (i = 0; i < count && !ret; i++) {
 471                 struct object *o = objects[i].item;
 472                 const char *name = objects[i].name;
 473                 switch (o->type) {
 474                 case OBJ_BLOB:
 475                         ret = show_blob_object(o->sha1, NULL);
 476                         break;
 477                 case OBJ_TAG: {
 478                         struct tag *t = (struct tag *)o;
 479
 480                         if (rev.shown_one)
 481                                 putchar('\n');
 482                         printf("%stag %s%s\n",
 483                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 484                                         t->tag,
 485                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 486                         ret = show_tag_object(o->sha1, &rev);
 487                         rev.shown_one = 1;
 488                         if (ret)
 489                                 break;
 490                         o = parse_object(t->tagged->sha1);
 491                         if (!o)
 492                                 ret = error(_("Could not read object %s"),
 493                                             sha1_to_hex(t->tagged->sha1));
 494                         objects[i].item = o;
 495                         i--;
 496                         break;
 497                 }
 498                 case OBJ_TREE:
 499                         if (rev.shown_one)
 500                                 putchar('\n');
 501                         printf("%stree %s%s\n\n",
 502                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 503                                         name,
 504                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 505                         read_tree_recursive((struct tree *)o, "", 0, 0, &match_all,
 506                                         show_tree_object, NULL);
 507                         rev.shown_one = 1;
 508                         break;
 509                 case OBJ_COMMIT:
 510                         rev.pending.nr = rev.pending.alloc = 0;
 511                         rev.pending.objects = NULL;
 512                         add_object_array(o, name, &rev.pending);
 513                         ret = cmd_log_walk(&rev);
 514                         break;
 515                 default:
 516                         ret = error(_("Unknown type: %d"), o->type);
 517                 }
 518         }
 519         free(objects);
 520         return ret;
 521 }
 522
 523 /*
 524  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
 525  */
 526 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
 527 {
 528         struct rev_info rev;
 529         struct setup_revision_opt opt;
 530
 531         git_config(git_log_config, NULL);
 532
 533         init_revisions(&rev, prefix);
 534         init_reflog_walk(&rev.reflog_info);
 535         rev.verbose_header = 1;
 536         memset(&opt, 0, sizeof(opt));
 537         opt.def = "HEAD";
 538         cmd_log_init_defaults(&rev);
 539         rev.abbrev_commit = 1;
 540         rev.commit_format = CMIT_FMT_ONELINE;
 541         rev.use_terminator = 1;
 542         rev.always_show_header = 1;
 543         cmd_log_init_finish(argc, argv, prefix, &rev, &opt);
 544
 545         return cmd_log_walk(&rev);
 546 }
 547
 548 int cmd_log(int argc, const char **argv, const char *prefix)
 549 {
 550         struct rev_info rev;
 551         struct setup_revision_opt opt;
 552
 553         git_config(git_log_config, NULL);
 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             !strcmp(var, "color.ui")) {
 625                 return 0;
 626         }
 627         if (!strcmp(var, "format.numbered")) {
 628                 if (value && !strcasecmp(value, "auto")) {
 629                         auto_number = 1;
 630                         return 0;
 631                 }
 632                 numbered = git_config_bool(var, value);
 633                 auto_number = auto_number && numbered;
 634                 return 0;
 635         }
 636         if (!strcmp(var, "format.attach")) {
 637                 if (value && *value)
 638                         default_attach = xstrdup(value);
 639                 else
 640                         default_attach = xstrdup(git_version_string);
 641                 return 0;
 642         }
 643         if (!strcmp(var, "format.thread")) {
 644                 if (value && !strcasecmp(value, "deep")) {
 645                         thread = THREAD_DEEP;
 646                         return 0;
 647                 }
 648                 if (value && !strcasecmp(value, "shallow")) {
 649                         thread = THREAD_SHALLOW;
 650                         return 0;
 651                 }
 652                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
 653                 return 0;
 654         }
 655         if (!strcmp(var, "format.signoff")) {
 656                 do_signoff = git_config_bool(var, value);
 657                 return 0;
 658         }
 659         if (!strcmp(var, "format.signature"))
 660                 return git_config_string(&signature, var, value);
 661
 662         return git_log_config(var, value, cb);
 663 }
 664
 665 static FILE *realstdout = NULL;
 666 static const char *output_directory = NULL;
 667 static int outdir_offset;
 668
 669 static int reopen_stdout(struct commit *commit, const char *subject,
 670                          struct rev_info *rev, int quiet)
 671 {
 672         struct strbuf filename = STRBUF_INIT;
 673         int suffix_len = strlen(fmt_patch_suffix) + 1;
 674
 675         if (output_directory) {
 676                 strbuf_addstr(&filename, output_directory);
 677                 if (filename.len >=
 678                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
 679                         return error(_("name of output directory is too long"));
 680                 if (filename.buf[filename.len - 1] != '/')
 681                         strbuf_addch(&filename, '/');
 682         }
 683
 684         get_patch_filename(commit, subject, rev->nr, fmt_patch_suffix, &filename);
 685
 686         if (!quiet)
 687                 fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
 688
 689         if (freopen(filename.buf, "w", stdout) == NULL)
 690                 return error(_("Cannot open patch file %s"), filename.buf);
 691
 692         strbuf_release(&filename);
 693         return 0;
 694 }
 695
 696 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids, const char *prefix)
 697 {
 698         struct rev_info check_rev;
 699         struct commit *commit;
 700         struct object *o1, *o2;
 701         unsigned flags1, flags2;
 702
 703         if (rev->pending.nr != 2)
 704                 die(_("Need exactly one range."));
 705
 706         o1 = rev->pending.objects[0].item;
 707         flags1 = o1->flags;
 708         o2 = rev->pending.objects[1].item;
 709         flags2 = o2->flags;
 710
 711         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
 712                 die(_("Not a range."));
 713
 714         init_patch_ids(ids);
 715
 716         /* given a range a..b get all patch ids for b..a */
 717         init_revisions(&check_rev, prefix);
 718         o1->flags ^= UNINTERESTING;
 719         o2->flags ^= UNINTERESTING;
 720         add_pending_object(&check_rev, o1, "o1");
 721         add_pending_object(&check_rev, o2, "o2");
 722         if (prepare_revision_walk(&check_rev))
 723                 die(_("revision walk setup failed"));
 724
 725         while ((commit = get_revision(&check_rev)) != NULL) {
 726                 /* ignore merges */
 727                 if (commit->parents && commit->parents->next)
 728                         continue;
 729
 730                 add_commit_patch_id(commit, ids);
 731         }
 732
 733         /* reset for next revision walk */
 734         clear_commit_marks((struct commit *)o1,
 735                         SEEN | UNINTERESTING | SHOWN | ADDED);
 736         clear_commit_marks((struct commit *)o2,
 737                         SEEN | UNINTERESTING | SHOWN | ADDED);
 738         o1->flags = flags1;
 739         o2->flags = flags2;
 740 }
 741
 742 static void gen_message_id(struct rev_info *info, char *base)
 743 {
 744         struct strbuf buf = STRBUF_INIT;
 745         strbuf_addf(&buf, "%s.%lu.git.%s", base,
 746                     (unsigned long) time(NULL),
 747                     git_committer_info(IDENT_NO_NAME|IDENT_NO_DATE|IDENT_STRICT));
 748         info->message_id = strbuf_detach(&buf, NULL);
 749 }
 750
 751 static void print_signature(void)
 752 {
 753         if (signature && *signature)
 754                 printf("-- \n%s\n\n", signature);
 755 }
 756
 757 static void add_branch_description(struct strbuf *buf, const char *branch_name)
 758 {
 759         struct strbuf desc = STRBUF_INIT;
 760         if (!branch_name || !*branch_name)
 761                 return;
 762         read_branch_desc(&desc, branch_name);
 763         if (desc.len) {
 764                 strbuf_addch(buf, '\n');
 765                 strbuf_add(buf, desc.buf, desc.len);
 766                 strbuf_addch(buf, '\n');
 767         }
 768 }
 769
 770 static void make_cover_letter(struct rev_info *rev, int use_stdout,
 771                               int numbered, int numbered_files,
 772                               struct commit *origin,
 773                               int nr, struct commit **list, struct commit *head,
 774                               const char *branch_name,
 775                               int quiet)
 776 {
 777         const char *committer;
 778         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
 779         const char *msg;
 780         struct shortlog log;
 781         struct strbuf sb = STRBUF_INIT;
 782         int i;
 783         const char *encoding = "UTF-8";
 784         struct diff_options opts;
 785         int need_8bit_cte = 0;
 786         struct pretty_print_context pp = {0};
 787
 788         if (rev->commit_format != CMIT_FMT_EMAIL)
 789                 die(_("Cover letter needs email format"));
 790
 791         committer = git_committer_info(0);
 792
 793         if (!use_stdout &&
 794             reopen_stdout(NULL, numbered_files ? NULL : "cover-letter", rev, quiet))
 795                 return;
 796
 797         log_write_email_headers(rev, head, &pp.subject, &pp.after_subject,
 798                                 &need_8bit_cte);
 799
 800         for (i = 0; !need_8bit_cte && i < nr; i++)
 801                 if (has_non_ascii(list[i]->buffer))
 802                         need_8bit_cte = 1;
 803
 804         msg = body;
 805         pp.fmt = CMIT_FMT_EMAIL;
 806         pp.date_mode = DATE_RFC2822;
 807         pp_user_info(&pp, NULL, &sb, committer, encoding);
 808         pp_title_line(&pp, &msg, &sb, encoding, need_8bit_cte);
 809         pp_remainder(&pp, &msg, &sb, 0);
 810         add_branch_description(&sb, branch_name);
 811         printf("%s\n", sb.buf);
 812
 813         strbuf_release(&sb);
 814
 815         shortlog_init(&log);
 816         log.wrap_lines = 1;
 817         log.wrap = 72;
 818         log.in1 = 2;
 819         log.in2 = 4;
 820         for (i = 0; i < nr; i++)
 821                 shortlog_add_commit(&log, list[i]);
 822
 823         shortlog_output(&log);
 824
 825         /*
 826          * We can only do diffstat with a unique reference point
 827          */
 828         if (!origin)
 829                 return;
 830
 831         memcpy(&opts, &rev->diffopt, sizeof(opts));
 832         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
 833
 834         diff_setup_done(&opts);
 835
 836         diff_tree_sha1(origin->tree->object.sha1,
 837                        head->tree->object.sha1,
 838                        "", &opts);
 839         diffcore_std(&opts);
 840         diff_flush(&opts);
 841
 842         printf("\n");
 843         print_signature();
 844 }
 845
 846 static const char *clean_message_id(const char *msg_id)
 847 {
 848         char ch;
 849         const char *a, *z, *m;
 850
 851         m = msg_id;
 852         while ((ch = *m) && (isspace(ch) || (ch == '<')))
 853                 m++;
 854         a = m;
 855         z = NULL;
 856         while ((ch = *m)) {
 857                 if (!isspace(ch) && (ch != '>'))
 858                         z = m;
 859                 m++;
 860         }
 861         if (!z)
 862                 die(_("insane in-reply-to: %s"), msg_id);
 863         if (++z == m)
 864                 return a;
 865         return xmemdupz(a, z - a);
 866 }
 867
 868 static const char *set_outdir(const char *prefix, const char *output_directory)
 869 {
 870         if (output_directory && is_absolute_path(output_directory))
 871                 return output_directory;
 872
 873         if (!prefix || !*prefix) {
 874                 if (output_directory)
 875                         return output_directory;
 876                 /* The user did not explicitly ask for "./" */
 877                 outdir_offset = 2;
 878                 return "./";
 879         }
 880
 881         outdir_offset = strlen(prefix);
 882         if (!output_directory)
 883                 return prefix;
 884
 885         return xstrdup(prefix_filename(prefix, outdir_offset,
 886                                        output_directory));
 887 }
 888
 889 static const char * const builtin_format_patch_usage[] = {
 890         "git format-patch [options] [<since> | <revision range>]",
 891         NULL
 892 };
 893
 894 static int keep_subject = 0;
 895
 896 static int keep_callback(const struct option *opt, const char *arg, int unset)
 897 {
 898         ((struct rev_info *)opt->value)->total = -1;
 899         keep_subject = 1;
 900         return 0;
 901 }
 902
 903 static int subject_prefix = 0;
 904
 905 static int subject_prefix_callback(const struct option *opt, const char *arg,
 906                             int unset)
 907 {
 908         subject_prefix = 1;
 909         ((struct rev_info *)opt->value)->subject_prefix = arg;
 910         return 0;
 911 }
 912
 913 static int numbered_cmdline_opt = 0;
 914
 915 static int numbered_callback(const struct option *opt, const char *arg,
 916                              int unset)
 917 {
 918         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
 919         if (unset)
 920                 auto_number =  0;
 921         return 0;
 922 }
 923
 924 static int no_numbered_callback(const struct option *opt, const char *arg,
 925                                 int unset)
 926 {
 927         return numbered_callback(opt, arg, 1);
 928 }
 929
 930 static int output_directory_callback(const struct option *opt, const char *arg,
 931                               int unset)
 932 {
 933         const char **dir = (const char **)opt->value;
 934         if (*dir)
 935                 die(_("Two output directories?"));
 936         *dir = arg;
 937         return 0;
 938 }
 939
 940 static int thread_callback(const struct option *opt, const char *arg, int unset)
 941 {
 942         int *thread = (int *)opt->value;
 943         if (unset)
 944                 *thread = 0;
 945         else if (!arg || !strcmp(arg, "shallow"))
 946                 *thread = THREAD_SHALLOW;
 947         else if (!strcmp(arg, "deep"))
 948                 *thread = THREAD_DEEP;
 949         else
 950                 return 1;
 951         return 0;
 952 }
 953
 954 static int attach_callback(const struct option *opt, const char *arg, int unset)
 955 {
 956         struct rev_info *rev = (struct rev_info *)opt->value;
 957         if (unset)
 958                 rev->mime_boundary = NULL;
 959         else if (arg)
 960                 rev->mime_boundary = arg;
 961         else
 962                 rev->mime_boundary = git_version_string;
 963         rev->no_inline = unset ? 0 : 1;
 964         return 0;
 965 }
 966
 967 static int inline_callback(const struct option *opt, const char *arg, int unset)
 968 {
 969         struct rev_info *rev = (struct rev_info *)opt->value;
 970         if (unset)
 971                 rev->mime_boundary = NULL;
 972         else if (arg)
 973                 rev->mime_boundary = arg;
 974         else
 975                 rev->mime_boundary = git_version_string;
 976         rev->no_inline = 0;
 977         return 0;
 978 }
 979
 980 static int header_callback(const struct option *opt, const char *arg, int unset)
 981 {
 982         if (unset) {
 983                 string_list_clear(&extra_hdr, 0);
 984                 string_list_clear(&extra_to, 0);
 985                 string_list_clear(&extra_cc, 0);
 986         } else {
 987             add_header(arg);
 988         }
 989         return 0;
 990 }
 991
 992 static int to_callback(const struct option *opt, const char *arg, int unset)
 993 {
 994         if (unset)
 995                 string_list_clear(&extra_to, 0);
 996         else
 997                 string_list_append(&extra_to, arg);
 998         return 0;
 999 }
1000
1001 static int cc_callback(const struct option *opt, const char *arg, int unset)
1002 {
1003         if (unset)
1004                 string_list_clear(&extra_cc, 0);
1005         else
1006                 string_list_append(&extra_cc, arg);
1007         return 0;
1008 }
1009
1010 static char *find_branch_name(struct rev_info *rev)
1011 {
1012         int i, positive = -1;
1013         unsigned char branch_sha1[20];
1014         struct strbuf buf = STRBUF_INIT;
1015         const char *branch;
1016
1017         for (i = 0; i < rev->cmdline.nr; i++) {
1018                 if (rev->cmdline.rev[i].flags & UNINTERESTING)
1019                         continue;
1020                 if (positive < 0)
1021                         positive = i;
1022                 else
1023                         return NULL;
1024         }
1025         if (positive < 0)
1026                 return NULL;
1027         strbuf_addf(&buf, "refs/heads/%s", rev->cmdline.rev[positive].name);
1028         branch = resolve_ref_unsafe(buf.buf, branch_sha1, 1, NULL);
1029         if (!branch ||
1030             prefixcmp(branch, "refs/heads/") ||
1031             hashcmp(rev->cmdline.rev[positive].item->sha1, branch_sha1))
1032                 branch = NULL;
1033         strbuf_release(&buf);
1034         if (branch)
1035                 return xstrdup(rev->cmdline.rev[positive].name);
1036         return NULL;
1037 }
1038
1039 int cmd_format_patch(int argc, const char **argv, const char *prefix)
1040 {
1041         struct commit *commit;
1042         struct commit **list = NULL;
1043         struct rev_info rev;
1044         struct setup_revision_opt s_r_opt;
1045         int nr = 0, total, i;
1046         int use_stdout = 0;
1047         int start_number = -1;
1048         int numbered_files = 0;         /* _just_ numbers */
1049         int ignore_if_in_upstream = 0;
1050         int cover_letter = 0;
1051         int boundary_count = 0;
1052         int no_binary_diff = 0;
1053         struct commit *origin = NULL, *head = NULL;
1054         const char *in_reply_to = NULL;
1055         struct patch_ids ids;
1056         char *add_signoff = NULL;
1057         struct strbuf buf = STRBUF_INIT;
1058         int use_patch_format = 0;
1059         int quiet = 0;
1060         char *branch_name = NULL;
1061         const struct option builtin_format_patch_options[] = {
1062                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
1063                             "use [PATCH n/m] even with a single patch",
1064                             PARSE_OPT_NOARG, numbered_callback },
1065                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
1066                             "use [PATCH] even with multiple patches",
1067                             PARSE_OPT_NOARG, no_numbered_callback },
1068                 OPT_BOOLEAN('s', "signoff", &do_signoff, "add Signed-off-by:"),
1069                 OPT_BOOLEAN(0, "stdout", &use_stdout,
1070                             "print patches to standard out"),
1071                 OPT_BOOLEAN(0, "cover-letter", &cover_letter,
1072                             "generate a cover letter"),
1073                 OPT_BOOLEAN(0, "numbered-files", &numbered_files,
1074                             "use simple number sequence for output file names"),
1075                 OPT_STRING(0, "suffix", &fmt_patch_suffix, "sfx",
1076                             "use <sfx> instead of '.patch'"),
1077                 OPT_INTEGER(0, "start-number", &start_number,
1078                             "start numbering patches at <n> instead of 1"),
1079                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, "prefix",
1080                             "Use [<prefix>] instead of [PATCH]",
1081                             PARSE_OPT_NONEG, subject_prefix_callback },
1082                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
1083                             "dir", "store resulting files in <dir>",
1084                             PARSE_OPT_NONEG, output_directory_callback },
1085                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
1086                             "don't strip/add [PATCH]",
1087                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
1088                 OPT_BOOLEAN(0, "no-binary", &no_binary_diff,
1089                             "don't output binary diffs"),
1090                 OPT_BOOLEAN(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
1091                             "don't include a patch matching a commit upstream"),
1092                 { OPTION_BOOLEAN, 'p', "no-stat", &use_patch_format, NULL,
1093                   "show patch format instead of default (patch + stat)",
1094                   PARSE_OPT_NONEG | PARSE_OPT_NOARG },
1095                 OPT_GROUP("Messaging"),
1096                 { OPTION_CALLBACK, 0, "add-header", NULL, "header",
1097                             "add email header", 0, header_callback },
1098                 { OPTION_CALLBACK, 0, "to", NULL, "email", "add To: header",
1099                             0, to_callback },
1100                 { OPTION_CALLBACK, 0, "cc", NULL, "email", "add Cc: header",
1101                             0, cc_callback },
1102                 OPT_STRING(0, "in-reply-to", &in_reply_to, "message-id",
1103                             "make first mail a reply to <message-id>"),
1104                 { OPTION_CALLBACK, 0, "attach", &rev, "boundary",
1105                             "attach the patch", PARSE_OPT_OPTARG,
1106                             attach_callback },
1107                 { OPTION_CALLBACK, 0, "inline", &rev, "boundary",
1108                             "inline the patch",
1109                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
1110                             inline_callback },
1111                 { OPTION_CALLBACK, 0, "thread", &thread, "style",
1112                             "enable message threading, styles: shallow, deep",
1113                             PARSE_OPT_OPTARG, thread_callback },
1114                 OPT_STRING(0, "signature", &signature, "signature",
1115                             "add a signature"),
1116                 OPT_BOOLEAN(0, "quiet", &quiet,
1117                             "don't print the patch filenames"),
1118                 OPT_END()
1119         };
1120
1121         extra_hdr.strdup_strings = 1;
1122         extra_to.strdup_strings = 1;
1123         extra_cc.strdup_strings = 1;
1124         git_config(git_format_config, NULL);
1125         init_revisions(&rev, prefix);
1126         rev.commit_format = CMIT_FMT_EMAIL;
1127         rev.verbose_header = 1;
1128         rev.diff = 1;
1129         rev.max_parents = 1;
1130         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
1131         rev.subject_prefix = fmt_patch_subject_prefix;
1132         memset(&s_r_opt, 0, sizeof(s_r_opt));
1133         s_r_opt.def = "HEAD";
1134
1135         if (default_attach) {
1136                 rev.mime_boundary = default_attach;
1137                 rev.no_inline = 1;
1138         }
1139
1140         /*
1141          * Parse the arguments before setup_revisions(), or something
1142          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1143          * possibly a valid SHA1.
1144          */
1145         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1146                              builtin_format_patch_usage,
1147                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1148                              PARSE_OPT_KEEP_DASHDASH);
1149
1150         if (do_signoff) {
1151                 const char *committer;
1152                 const char *endpos;
1153                 committer = git_committer_info(IDENT_STRICT);
1154                 endpos = strchr(committer, '>');
1155                 if (!endpos)
1156                         die(_("bogus committer info %s"), committer);
1157                 add_signoff = xmemdupz(committer, endpos - committer + 1);
1158         }
1159
1160         for (i = 0; i < extra_hdr.nr; i++) {
1161                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1162                 strbuf_addch(&buf, '\n');
1163         }
1164
1165         if (extra_to.nr)
1166                 strbuf_addstr(&buf, "To: ");
1167         for (i = 0; i < extra_to.nr; i++) {
1168                 if (i)
1169                         strbuf_addstr(&buf, "    ");
1170                 strbuf_addstr(&buf, extra_to.items[i].string);
1171                 if (i + 1 < extra_to.nr)
1172                         strbuf_addch(&buf, ',');
1173                 strbuf_addch(&buf, '\n');
1174         }
1175
1176         if (extra_cc.nr)
1177                 strbuf_addstr(&buf, "Cc: ");
1178         for (i = 0; i < extra_cc.nr; i++) {
1179                 if (i)
1180                         strbuf_addstr(&buf, "    ");
1181                 strbuf_addstr(&buf, extra_cc.items[i].string);
1182                 if (i + 1 < extra_cc.nr)
1183                         strbuf_addch(&buf, ',');
1184                 strbuf_addch(&buf, '\n');
1185         }
1186
1187         rev.extra_headers = strbuf_detach(&buf, NULL);
1188
1189         if (start_number < 0)
1190                 start_number = 1;
1191
1192         /*
1193          * If numbered is set solely due to format.numbered in config,
1194          * and it would conflict with --keep-subject (-k) from the
1195          * command line, reset "numbered".
1196          */
1197         if (numbered && keep_subject && !numbered_cmdline_opt)
1198                 numbered = 0;
1199
1200         if (numbered && keep_subject)
1201                 die (_("-n and -k are mutually exclusive."));
1202         if (keep_subject && subject_prefix)
1203                 die (_("--subject-prefix and -k are mutually exclusive."));
1204         rev.preserve_subject = keep_subject;
1205
1206         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1207         if (argc > 1)
1208                 die (_("unrecognized argument: %s"), argv[1]);
1209
1210         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1211                 die(_("--name-only does not make sense"));
1212         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1213                 die(_("--name-status does not make sense"));
1214         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1215                 die(_("--check does not make sense"));
1216
1217         if (!use_patch_format &&
1218                 (!rev.diffopt.output_format ||
1219                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1220                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1221
1222         /* Always generate a patch */
1223         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1224
1225         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1226                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1227
1228         if (rev.show_notes)
1229                 init_display_notes(&rev.notes_opt);
1230
1231         if (!use_stdout)
1232                 output_directory = set_outdir(prefix, output_directory);
1233         else
1234                 setup_pager();
1235
1236         if (output_directory) {
1237                 if (use_stdout)
1238                         die(_("standard output, or directory, which one?"));
1239                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1240                         die_errno(_("Could not create directory '%s'"),
1241                                   output_directory);
1242         }
1243
1244         if (rev.pending.nr == 1) {
1245                 if (rev.max_count < 0 && !rev.show_root_diff) {
1246                         /*
1247                          * This is traditional behaviour of "git format-patch
1248                          * origin" that prepares what the origin side still
1249                          * does not have.
1250                          */
1251                         unsigned char sha1[20];
1252                         const char *ref;
1253
1254                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1255                         add_head_to_pending(&rev);
1256                         ref = resolve_ref_unsafe("HEAD", sha1, 1, NULL);
1257                         if (ref && !prefixcmp(ref, "refs/heads/"))
1258                                 branch_name = xstrdup(ref + strlen("refs/heads/"));
1259                         else
1260                                 branch_name = xstrdup(""); /* no branch */
1261                 }
1262                 /*
1263                  * Otherwise, it is "format-patch -22 HEAD", and/or
1264                  * "format-patch --root HEAD".  The user wants
1265                  * get_revision() to do the usual traversal.
1266                  */
1267         }
1268
1269         /*
1270          * We cannot move this anywhere earlier because we do want to
1271          * know if --root was given explicitly from the command line.
1272          */
1273         rev.show_root_diff = 1;
1274
1275         if (cover_letter) {
1276                 /*
1277                  * NEEDSWORK:randomly pick one positive commit to show
1278                  * diffstat; this is often the tip and the command
1279                  * happens to do the right thing in most cases, but a
1280                  * complex command like "--cover-letter a b c ^bottom"
1281                  * picks "c" and shows diffstat between bottom..c
1282                  * which may not match what the series represents at
1283                  * all and totally broken.
1284                  */
1285                 int i;
1286                 for (i = 0; i < rev.pending.nr; i++) {
1287                         struct object *o = rev.pending.objects[i].item;
1288                         if (!(o->flags & UNINTERESTING))
1289                                 head = (struct commit *)o;
1290                 }
1291                 /* There is nothing to show; it is not an error, though. */
1292                 if (!head)
1293                         return 0;
1294                 if (!branch_name)
1295                         branch_name = find_branch_name(&rev);
1296         }
1297
1298         if (ignore_if_in_upstream) {
1299                 /* Don't say anything if head and upstream are the same. */
1300                 if (rev.pending.nr == 2) {
1301                         struct object_array_entry *o = rev.pending.objects;
1302                         if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1303                                 return 0;
1304                 }
1305                 get_patch_ids(&rev, &ids, prefix);
1306         }
1307
1308         if (!use_stdout)
1309                 realstdout = xfdopen(xdup(1), "w");
1310
1311         if (prepare_revision_walk(&rev))
1312                 die(_("revision walk setup failed"));
1313         rev.boundary = 1;
1314         while ((commit = get_revision(&rev)) != NULL) {
1315                 if (commit->object.flags & BOUNDARY) {
1316                         boundary_count++;
1317                         origin = (boundary_count == 1) ? commit : NULL;
1318                         continue;
1319                 }
1320
1321                 if (ignore_if_in_upstream &&
1322                                 has_commit_patch_id(commit, &ids))
1323                         continue;
1324
1325                 nr++;
1326                 list = xrealloc(list, nr * sizeof(list[0]));
1327                 list[nr - 1] = commit;
1328         }
1329         total = nr;
1330         if (!keep_subject && auto_number && total > 1)
1331                 numbered = 1;
1332         if (numbered)
1333                 rev.total = total + start_number - 1;
1334         if (in_reply_to || thread || cover_letter)
1335                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1336         if (in_reply_to) {
1337                 const char *msgid = clean_message_id(in_reply_to);
1338                 string_list_append(rev.ref_message_ids, msgid);
1339         }
1340         rev.numbered_files = numbered_files;
1341         rev.patch_suffix = fmt_patch_suffix;
1342         if (cover_letter) {
1343                 if (thread)
1344                         gen_message_id(&rev, "cover");
1345                 make_cover_letter(&rev, use_stdout, numbered, numbered_files,
1346                                   origin, nr, list, head, branch_name, quiet);
1347                 total++;
1348                 start_number--;
1349         }
1350         rev.add_signoff = add_signoff;
1351         while (0 <= --nr) {
1352                 int shown;
1353                 commit = list[nr];
1354                 rev.nr = total - nr + (start_number - 1);
1355                 /* Make the second and subsequent mails replies to the first */
1356                 if (thread) {
1357                         /* Have we already had a message ID? */
1358                         if (rev.message_id) {
1359                                 /*
1360                                  * For deep threading: make every mail
1361                                  * a reply to the previous one, no
1362                                  * matter what other options are set.
1363                                  *
1364                                  * For shallow threading:
1365                                  *
1366                                  * Without --cover-letter and
1367                                  * --in-reply-to, make every mail a
1368                                  * reply to the one before.
1369                                  *
1370                                  * With --in-reply-to but no
1371                                  * --cover-letter, make every mail a
1372                                  * reply to the <reply-to>.
1373                                  *
1374                                  * With --cover-letter, make every
1375                                  * mail but the cover letter a reply
1376                                  * to the cover letter.  The cover
1377                                  * letter is a reply to the
1378                                  * --in-reply-to, if specified.
1379                                  */
1380                                 if (thread == THREAD_SHALLOW
1381                                     && rev.ref_message_ids->nr > 0
1382                                     && (!cover_letter || rev.nr > 1))
1383                                         free(rev.message_id);
1384                                 else
1385                                         string_list_append(rev.ref_message_ids,
1386                                                            rev.message_id);
1387                         }
1388                         gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
1389                 }
1390
1391                 if (!use_stdout &&
1392                     reopen_stdout(numbered_files ? NULL : commit, NULL, &rev, quiet))
1393                         die(_("Failed to create output files"));
1394                 shown = log_tree_commit(&rev, commit);
1395                 free(commit->buffer);
1396                 commit->buffer = NULL;
1397
1398                 /* We put one extra blank line between formatted
1399                  * patches and this flag is used by log-tree code
1400                  * to see if it needs to emit a LF before showing
1401                  * the log; when using one file per patch, we do
1402                  * not want the extra blank line.
1403                  */
1404                 if (!use_stdout)
1405                         rev.shown_one = 0;
1406                 if (shown) {
1407                         if (rev.mime_boundary)
1408                                 printf("\n--%s%s--\n\n\n",
1409                                        mime_boundary_leader,
1410                                        rev.mime_boundary);
1411                         else
1412                                 print_signature();
1413                 }
1414                 if (!use_stdout)
1415                         fclose(stdout);
1416         }
1417         free(list);
1418         free(branch_name);
1419         string_list_clear(&extra_to, 0);
1420         string_list_clear(&extra_cc, 0);
1421         string_list_clear(&extra_hdr, 0);
1422         if (ignore_if_in_upstream)
1423                 free_patch_ids(&ids);
1424         return 0;
1425 }
1426
1427 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1428 {
1429         unsigned char sha1[20];
1430         if (get_sha1(arg, sha1) == 0) {
1431                 struct commit *commit = lookup_commit_reference(sha1);
1432                 if (commit) {
1433                         commit->object.flags |= flags;
1434                         add_pending_object(revs, &commit->object, arg);
1435                         return 0;
1436                 }
1437         }
1438         return -1;
1439 }
1440
1441 static const char * const cherry_usage[] = {
1442         "git cherry [-v] [<upstream> [<head> [<limit>]]]",
1443         NULL
1444 };
1445
1446 static void print_commit(char sign, struct commit *commit, int verbose,
1447                          int abbrev)
1448 {
1449         if (!verbose) {
1450                 printf("%c %s\n", sign,
1451                        find_unique_abbrev(commit->object.sha1, abbrev));
1452         } else {
1453                 struct strbuf buf = STRBUF_INIT;
1454                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
1455                 printf("%c %s %s\n", sign,
1456                        find_unique_abbrev(commit->object.sha1, abbrev),
1457                        buf.buf);
1458                 strbuf_release(&buf);
1459         }
1460 }
1461
1462 int cmd_cherry(int argc, const char **argv, const char *prefix)
1463 {
1464         struct rev_info revs;
1465         struct patch_ids ids;
1466         struct commit *commit;
1467         struct commit_list *list = NULL;
1468         struct branch *current_branch;
1469         const char *upstream;
1470         const char *head = "HEAD";
1471         const char *limit = NULL;
1472         int verbose = 0, abbrev = 0;
1473
1474         struct option options[] = {
1475                 OPT__ABBREV(&abbrev),
1476                 OPT__VERBOSE(&verbose, "be verbose"),
1477                 OPT_END()
1478         };
1479
1480         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
1481
1482         switch (argc) {
1483         case 3:
1484                 limit = argv[2];
1485                 /* FALLTHROUGH */
1486         case 2:
1487                 head = argv[1];
1488                 /* FALLTHROUGH */
1489         case 1:
1490                 upstream = argv[0];
1491                 break;
1492         default:
1493                 current_branch = branch_get(NULL);
1494                 if (!current_branch || !current_branch->merge
1495                                         || !current_branch->merge[0]
1496                                         || !current_branch->merge[0]->dst) {
1497                         fprintf(stderr, _("Could not find a tracked"
1498                                         " remote branch, please"
1499                                         " specify <upstream> manually.\n"));
1500                         usage_with_options(cherry_usage, options);
1501                 }
1502
1503                 upstream = current_branch->merge[0]->dst;
1504         }
1505
1506         init_revisions(&revs, prefix);
1507         revs.diff = 1;
1508         revs.combine_merges = 0;
1509         revs.ignore_merges = 1;
1510         DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
1511
1512         if (add_pending_commit(head, &revs, 0))
1513                 die(_("Unknown commit %s"), head);
1514         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1515                 die(_("Unknown commit %s"), upstream);
1516
1517         /* Don't say anything if head and upstream are the same. */
1518         if (revs.pending.nr == 2) {
1519                 struct object_array_entry *o = revs.pending.objects;
1520                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1521                         return 0;
1522         }
1523
1524         get_patch_ids(&revs, &ids, prefix);
1525
1526         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1527                 die(_("Unknown commit %s"), limit);
1528
1529         /* reverse the list of commits */
1530         if (prepare_revision_walk(&revs))
1531                 die(_("revision walk setup failed"));
1532         while ((commit = get_revision(&revs)) != NULL) {
1533                 /* ignore merges */
1534                 if (commit->parents && commit->parents->next)
1535                         continue;
1536
1537                 commit_list_insert(commit, &list);
1538         }
1539
1540         while (list) {
1541                 char sign = '+';
1542
1543                 commit = list->item;
1544                 if (has_commit_patch_id(commit, &ids))
1545                         sign = '-';
1546                 print_commit(sign, commit, verbose, abbrev);
1547                 list = list->next;
1548         }
1549
1550         free_patch_ids(&ids);
1551         return 0;
1552 }