builtin/log.c

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