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 #include "version.h"
  25
  26 /* Set a default date-time format for git log ("log.date" config variable) */
  27 static const char *default_date_mode = NULL;
  28
  29 static int default_abbrev_commit;
  30 static int default_show_root = 1;
  31 static int decoration_style;
  32 static int decoration_given;
  33 static const char *fmt_patch_subject_prefix = "PATCH";
  34 static const char *fmt_pretty;
  35
  36 static const char * const builtin_log_usage[] = {
  37         "git log [<options>] [<since>..<until>] [[--] <path>...]\n"
  38         "   or: git show [options] <object>...",
  39         NULL
  40 };
  41
  42 static int parse_decoration_style(const char *var, const char *value)
  43 {
  44         switch (git_config_maybe_bool(var, value)) {
  45         case 1:
  46                 return DECORATE_SHORT_REFS;
  47         case 0:
  48                 return 0;
  49         default:
  50                 break;
  51         }
  52         if (!strcmp(value, "full"))
  53                 return DECORATE_FULL_REFS;
  54         else if (!strcmp(value, "short"))
  55                 return DECORATE_SHORT_REFS;
  56         return -1;
  57 }
  58
  59 static int decorate_callback(const struct option *opt, const char *arg, int unset)
  60 {
  61         if (unset)
  62                 decoration_style = 0;
  63         else if (arg)
  64                 decoration_style = parse_decoration_style("command line", arg);
  65         else
  66                 decoration_style = DECORATE_SHORT_REFS;
  67
  68         if (decoration_style < 0)
  69                 die("invalid --decorate option: %s", arg);
  70
  71         decoration_given = 1;
  72
  73         return 0;
  74 }
  75
  76 static void cmd_log_init_defaults(struct rev_info *rev)
  77 {
  78         if (fmt_pretty)
  79                 get_commit_format(fmt_pretty, rev);
  80         rev->verbose_header = 1;
  81         DIFF_OPT_SET(&rev->diffopt, RECURSIVE);
  82         rev->diffopt.stat_width = -1; /* use full terminal width */
  83         rev->diffopt.stat_graph_width = -1; /* respect statGraphWidth config */
  84         rev->abbrev_commit = default_abbrev_commit;
  85         rev->show_root_diff = default_show_root;
  86         rev->subject_prefix = fmt_patch_subject_prefix;
  87         DIFF_OPT_SET(&rev->diffopt, ALLOW_TEXTCONV);
  88
  89         if (default_date_mode)
  90                 rev->date_mode = parse_date_format(default_date_mode);
  91 }
  92
  93 static void cmd_log_init_finish(int argc, const char **argv, const char *prefix,
  94                          struct rev_info *rev, struct setup_revision_opt *opt)
  95 {
  96         struct userformat_want w;
  97         int quiet = 0, source = 0;
  98
  99         const struct option builtin_log_options[] = {
 100                 OPT_BOOLEAN(0, "quiet", &quiet, "suppress diff output"),
 101                 OPT_BOOLEAN(0, "source", &source, "show source"),
 102                 { OPTION_CALLBACK, 0, "decorate", NULL, NULL, "decorate options",
 103                   PARSE_OPT_OPTARG, decorate_callback},
 104                 OPT_END()
 105         };
 106
 107         argc = parse_options(argc, argv, prefix,
 108                              builtin_log_options, builtin_log_usage,
 109                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
 110                              PARSE_OPT_KEEP_DASHDASH);
 111
 112         argc = setup_revisions(argc, argv, rev, opt);
 113         if (quiet)
 114                 rev->diffopt.output_format |= DIFF_FORMAT_NO_OUTPUT;
 115
 116         /* Any arguments at this point are not recognized */
 117         if (argc > 1)
 118                 die("unrecognized argument: %s", argv[1]);
 119
 120         memset(&w, 0, sizeof(w));
 121         userformat_find_requirements(NULL, &w);
 122
 123         if (!rev->show_notes_given && (!rev->pretty_given || w.notes))
 124                 rev->show_notes = 1;
 125         if (rev->show_notes)
 126                 init_display_notes(&rev->notes_opt);
 127
 128         if (rev->diffopt.pickaxe || rev->diffopt.filter)
 129                 rev->always_show_header = 0;
 130         if (DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES)) {
 131                 rev->always_show_header = 0;
 132                 if (rev->diffopt.pathspec.nr != 1)
 133                         usage("git logs can only follow renames on one pathname at a time");
 134         }
 135
 136         if (source)
 137                 rev->show_source = 1;
 138
 139         if (rev->pretty_given && rev->commit_format == CMIT_FMT_RAW) {
 140                 /*
 141                  * "log --pretty=raw" is special; ignore UI oriented
 142                  * configuration variables such as decoration.
 143                  */
 144                 if (!decoration_given)
 145                         decoration_style = 0;
 146                 if (!rev->abbrev_commit_given)
 147                         rev->abbrev_commit = 0;
 148         }
 149
 150         if (decoration_style) {
 151                 rev->show_decorations = 1;
 152                 load_ref_decorations(decoration_style);
 153         }
 154         setup_pager();
 155 }
 156
 157 static void cmd_log_init(int argc, const char **argv, const char *prefix,
 158                          struct rev_info *rev, struct setup_revision_opt *opt)
 159 {
 160         cmd_log_init_defaults(rev);
 161         cmd_log_init_finish(argc, argv, prefix, rev, opt);
 162 }
 163
 164 /*
 165  * This gives a rough estimate for how many commits we
 166  * will print out in the list.
 167  */
 168 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
 169 {
 170         int n = 0;
 171
 172         while (list) {
 173                 struct commit *commit = list->item;
 174                 unsigned int flags = commit->object.flags;
 175                 list = list->next;
 176                 if (!(flags & (TREESAME | UNINTERESTING)))
 177                         n++;
 178         }
 179         return n;
 180 }
 181
 182 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
 183 {
 184         if (rev->shown_one) {
 185                 rev->shown_one = 0;
 186                 if (rev->commit_format != CMIT_FMT_ONELINE)
 187                         putchar(rev->diffopt.line_termination);
 188         }
 189         printf(_("Final output: %d %s\n"), nr, stage);
 190 }
 191
 192 static struct itimerval early_output_timer;
 193
 194 static void log_show_early(struct rev_info *revs, struct commit_list *list)
 195 {
 196         int i = revs->early_output;
 197         int show_header = 1;
 198
 199         sort_in_topological_order(&list, revs->lifo);
 200         while (list && i) {
 201                 struct commit *commit = list->item;
 202                 switch (simplify_commit(revs, commit)) {
 203                 case commit_show:
 204                         if (show_header) {
 205                                 int n = estimate_commit_count(revs, list);
 206                                 show_early_header(revs, "incomplete", n);
 207                                 show_header = 0;
 208                         }
 209                         log_tree_commit(revs, commit);
 210                         i--;
 211                         break;
 212                 case commit_ignore:
 213                         break;
 214                 case commit_error:
 215                         return;
 216                 }
 217                 list = list->next;
 218         }
 219
 220         /* Did we already get enough commits for the early output? */
 221         if (!i)
 222                 return;
 223
 224         /*
 225          * ..if no, then repeat it twice a second until we
 226          * do.
 227          *
 228          * NOTE! We don't use "it_interval", because if the
 229          * reader isn't listening, we want our output to be
 230          * throttled by the writing, and not have the timer
 231          * trigger every second even if we're blocked on a
 232          * reader!
 233          */
 234         early_output_timer.it_value.tv_sec = 0;
 235         early_output_timer.it_value.tv_usec = 500000;
 236         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 237 }
 238
 239 static void early_output(int signal)
 240 {
 241         show_early_output = log_show_early;
 242 }
 243
 244 static void setup_early_output(struct rev_info *rev)
 245 {
 246         struct sigaction sa;
 247
 248         /*
 249          * Set up the signal handler, minimally intrusively:
 250          * we only set a single volatile integer word (not
 251          * using sigatomic_t - trying to avoid unnecessary
 252          * system dependencies and headers), and using
 253          * SA_RESTART.
 254          */
 255         memset(&sa, 0, sizeof(sa));
 256         sa.sa_handler = early_output;
 257         sigemptyset(&sa.sa_mask);
 258         sa.sa_flags = SA_RESTART;
 259         sigaction(SIGALRM, &sa, NULL);
 260
 261         /*
 262          * If we can get the whole output in less than a
 263          * tenth of a second, don't even bother doing the
 264          * early-output thing..
 265          *
 266          * This is a one-time-only trigger.
 267          */
 268         early_output_timer.it_value.tv_sec = 0;
 269         early_output_timer.it_value.tv_usec = 100000;
 270         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 271 }
 272
 273 static void finish_early_output(struct rev_info *rev)
 274 {
 275         int n = estimate_commit_count(rev, rev->commits);
 276         signal(SIGALRM, SIG_IGN);
 277         show_early_header(rev, "done", n);
 278 }
 279
 280 static int cmd_log_walk(struct rev_info *rev)
 281 {
 282         struct commit *commit;
 283         int saved_nrl = 0;
 284         int saved_dcctc = 0;
 285
 286         if (rev->early_output)
 287                 setup_early_output(rev);
 288
 289         if (prepare_revision_walk(rev))
 290                 die(_("revision walk setup failed"));
 291
 292         if (rev->early_output)
 293                 finish_early_output(rev);
 294
 295         /*
 296          * For --check and --exit-code, the exit code is based on CHECK_FAILED
 297          * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
 298          * retain that state information if replacing rev->diffopt in this loop
 299          */
 300         while ((commit = get_revision(rev)) != NULL) {
 301                 if (!log_tree_commit(rev, commit) &&
 302                     rev->max_count >= 0)
 303                         /*
 304                          * We decremented max_count in get_revision,
 305                          * but we didn't actually show the commit.
 306                          */
 307                         rev->max_count++;
 308                 if (!rev->reflog_info) {
 309                         /* we allow cycles in reflog ancestry */
 310                         free(commit->buffer);
 311                         commit->buffer = NULL;
 312                 }
 313                 free_commit_list(commit->parents);
 314                 commit->parents = NULL;
 315                 if (saved_nrl < rev->diffopt.needed_rename_limit)
 316                         saved_nrl = rev->diffopt.needed_rename_limit;
 317                 if (rev->diffopt.degraded_cc_to_c)
 318                         saved_dcctc = 1;
 319         }
 320         rev->diffopt.degraded_cc_to_c = saved_dcctc;
 321         rev->diffopt.needed_rename_limit = saved_nrl;
 322
 323         if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
 324             DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
 325                 return 02;
 326         }
 327         return diff_result_code(&rev->diffopt, 0);
 328 }
 329
 330 static int git_log_config(const char *var, const char *value, void *cb)
 331 {
 332         if (!strcmp(var, "format.pretty"))
 333                 return git_config_string(&fmt_pretty, var, value);
 334         if (!strcmp(var, "format.subjectprefix"))
 335                 return git_config_string(&fmt_patch_subject_prefix, var, value);
 336         if (!strcmp(var, "log.abbrevcommit")) {
 337                 default_abbrev_commit = git_config_bool(var, value);
 338                 return 0;
 339         }
 340         if (!strcmp(var, "log.date"))
 341                 return git_config_string(&default_date_mode, var, value);
 342         if (!strcmp(var, "log.decorate")) {
 343                 decoration_style = parse_decoration_style(var, value);
 344                 if (decoration_style < 0)
 345                         decoration_style = 0; /* maybe warn? */
 346                 return 0;
 347         }
 348         if (!strcmp(var, "log.showroot")) {
 349                 default_show_root = git_config_bool(var, value);
 350                 return 0;
 351         }
 352         if (!prefixcmp(var, "color.decorate."))
 353                 return parse_decorate_color_config(var, 15, value);
 354
 355         return git_diff_ui_config(var, value, cb);
 356 }
 357
 358 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 359 {
 360         struct rev_info rev;
 361         struct setup_revision_opt opt;
 362
 363         git_config(git_log_config, NULL);
 364
 365         init_revisions(&rev, prefix);
 366         rev.diff = 1;
 367         rev.simplify_history = 0;
 368         memset(&opt, 0, sizeof(opt));
 369         opt.def = "HEAD";
 370         opt.revarg_opt = REVARG_COMMITTISH;
 371         cmd_log_init(argc, argv, prefix, &rev, &opt);
 372         if (!rev.diffopt.output_format)
 373                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
 374         return cmd_log_walk(&rev);
 375 }
 376
 377 static void show_tagger(char *buf, int len, struct rev_info *rev)
 378 {
 379         struct strbuf out = STRBUF_INIT;
 380         struct pretty_print_context pp = {0};
 381
 382         pp.fmt = rev->commit_format;
 383         pp.date_mode = rev->date_mode;
 384         pp_user_info(&pp, "Tagger", &out, buf, get_log_output_encoding());
 385         printf("%s", out.buf);
 386         strbuf_release(&out);
 387 }
 388
 389 static int show_blob_object(const unsigned char *sha1, struct rev_info *rev)
 390 {
 391         fflush(stdout);
 392         return stream_blob_to_fd(1, sha1, NULL, 0);
 393 }
 394
 395 static int show_tag_object(const unsigned char *sha1, struct rev_info *rev)
 396 {
 397         unsigned long size;
 398         enum object_type type;
 399         char *buf = read_sha1_file(sha1, &type, &size);
 400         int offset = 0;
 401
 402         if (!buf)
 403                 return error(_("Could not read object %s"), sha1_to_hex(sha1));
 404
 405         assert(type == OBJ_TAG);
 406         while (offset < size && buf[offset] != '\n') {
 407                 int new_offset = offset + 1;
 408                 while (new_offset < size && buf[new_offset++] != '\n')
 409                         ; /* do nothing */
 410                 if (!prefixcmp(buf + offset, "tagger "))
 411                         show_tagger(buf + offset + 7,
 412                                     new_offset - offset - 7, rev);
 413                 offset = new_offset;
 414         }
 415
 416         if (offset < size)
 417                 fwrite(buf + offset, size - offset, 1, stdout);
 418         free(buf);
 419         return 0;
 420 }
 421
 422 static int show_tree_object(const unsigned char *sha1,
 423                 const char *base, int baselen,
 424                 const char *pathname, unsigned mode, int stage, void *context)
 425 {
 426         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
 427         return 0;
 428 }
 429
 430 static void show_rev_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
 431 {
 432         if (rev->ignore_merges) {
 433                 /* There was no "-m" on the command line */
 434                 rev->ignore_merges = 0;
 435                 if (!rev->first_parent_only && !rev->combine_merges) {
 436                         /* No "--first-parent", "-c", nor "--cc" */
 437                         rev->combine_merges = 1;
 438                         rev->dense_combined_merges = 1;
 439                 }
 440         }
 441         if (!rev->diffopt.output_format)
 442                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
 443 }
 444
 445 int cmd_show(int argc, const char **argv, const char *prefix)
 446 {
 447         struct rev_info rev;
 448         struct object_array_entry *objects;
 449         struct setup_revision_opt opt;
 450         struct pathspec match_all;
 451         int i, count, ret = 0;
 452
 453         git_config(git_log_config, NULL);
 454
 455         init_pathspec(&match_all, NULL);
 456         init_revisions(&rev, prefix);
 457         rev.diff = 1;
 458         rev.always_show_header = 1;
 459         rev.no_walk = 1;
 460         rev.diffopt.stat_width = -1;    /* Scale to real terminal size */
 461
 462         memset(&opt, 0, sizeof(opt));
 463         opt.def = "HEAD";
 464         opt.tweak = show_rev_tweak_rev;
 465         cmd_log_init(argc, argv, prefix, &rev, &opt);
 466
 467         if (!rev.no_walk)
 468                 return cmd_log_walk(&rev);
 469
 470         count = rev.pending.nr;
 471         objects = rev.pending.objects;
 472         for (i = 0; i < count && !ret; i++) {
 473                 struct object *o = objects[i].item;
 474                 const char *name = objects[i].name;
 475                 switch (o->type) {
 476                 case OBJ_BLOB:
 477                         ret = show_blob_object(o->sha1, NULL);
 478                         break;
 479                 case OBJ_TAG: {
 480                         struct tag *t = (struct tag *)o;
 481
 482                         if (rev.shown_one)
 483                                 putchar('\n');
 484                         printf("%stag %s%s\n",
 485                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 486                                         t->tag,
 487                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 488                         ret = show_tag_object(o->sha1, &rev);
 489                         rev.shown_one = 1;
 490                         if (ret)
 491                                 break;
 492                         o = parse_object(t->tagged->sha1);
 493                         if (!o)
 494                                 ret = error(_("Could not read object %s"),
 495                                             sha1_to_hex(t->tagged->sha1));
 496                         objects[i].item = o;
 497                         i--;
 498                         break;
 499                 }
 500                 case OBJ_TREE:
 501                         if (rev.shown_one)
 502                                 putchar('\n');
 503                         printf("%stree %s%s\n\n",
 504                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 505                                         name,
 506                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 507                         read_tree_recursive((struct tree *)o, "", 0, 0, &match_all,
 508                                         show_tree_object, NULL);
 509                         rev.shown_one = 1;
 510                         break;
 511                 case OBJ_COMMIT:
 512                         rev.pending.nr = rev.pending.alloc = 0;
 513                         rev.pending.objects = NULL;
 514                         add_object_array(o, name, &rev.pending);
 515                         ret = cmd_log_walk(&rev);
 516                         break;
 517                 default:
 518                         ret = error(_("Unknown type: %d"), o->type);
 519                 }
 520         }
 521         free(objects);
 522         return ret;
 523 }
 524
 525 /*
 526  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
 527  */
 528 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
 529 {
 530         struct rev_info rev;
 531         struct setup_revision_opt opt;
 532
 533         git_config(git_log_config, NULL);
 534
 535         init_revisions(&rev, prefix);
 536         init_reflog_walk(&rev.reflog_info);
 537         rev.verbose_header = 1;
 538         memset(&opt, 0, sizeof(opt));
 539         opt.def = "HEAD";
 540         cmd_log_init_defaults(&rev);
 541         rev.abbrev_commit = 1;
 542         rev.commit_format = CMIT_FMT_ONELINE;
 543         rev.use_terminator = 1;
 544         rev.always_show_header = 1;
 545         cmd_log_init_finish(argc, argv, prefix, &rev, &opt);
 546
 547         return cmd_log_walk(&rev);
 548 }
 549
 550 int cmd_log(int argc, const char **argv, const char *prefix)
 551 {
 552         struct rev_info rev;
 553         struct setup_revision_opt opt;
 554
 555         git_config(git_log_config, NULL);
 556
 557         init_revisions(&rev, prefix);
 558         rev.always_show_header = 1;
 559         memset(&opt, 0, sizeof(opt));
 560         opt.def = "HEAD";
 561         opt.revarg_opt = REVARG_COMMITTISH;
 562         cmd_log_init(argc, argv, prefix, &rev, &opt);
 563         return cmd_log_walk(&rev);
 564 }
 565
 566 /* format-patch */
 567
 568 static const char *fmt_patch_suffix = ".patch";
 569 static int numbered = 0;
 570 static int auto_number = 1;
 571
 572 static char *default_attach = NULL;
 573
 574 static struct string_list extra_hdr;
 575 static struct string_list extra_to;
 576 static struct string_list extra_cc;
 577
 578 static void add_header(const char *value)
 579 {
 580         struct string_list_item *item;
 581         int len = strlen(value);
 582         while (len && value[len - 1] == '\n')
 583                 len--;
 584
 585         if (!strncasecmp(value, "to: ", 4)) {
 586                 item = string_list_append(&extra_to, value + 4);
 587                 len -= 4;
 588         } else if (!strncasecmp(value, "cc: ", 4)) {
 589                 item = string_list_append(&extra_cc, value + 4);
 590                 len -= 4;
 591         } else {
 592                 item = string_list_append(&extra_hdr, value);
 593         }
 594
 595         item->string[len] = '\0';
 596 }
 597
 598 #define THREAD_SHALLOW 1
 599 #define THREAD_DEEP 2
 600 static int thread;
 601 static int do_signoff;
 602 static const char *signature = git_version_string;
 603
 604 static int git_format_config(const char *var, const char *value, void *cb)
 605 {
 606         if (!strcmp(var, "format.headers")) {
 607                 if (!value)
 608                         die(_("format.headers without value"));
 609                 add_header(value);
 610                 return 0;
 611         }
 612         if (!strcmp(var, "format.suffix"))
 613                 return git_config_string(&fmt_patch_suffix, var, value);
 614         if (!strcmp(var, "format.to")) {
 615                 if (!value)
 616                         return config_error_nonbool(var);
 617                 string_list_append(&extra_to, value);
 618                 return 0;
 619         }
 620         if (!strcmp(var, "format.cc")) {
 621                 if (!value)
 622                         return config_error_nonbool(var);
 623                 string_list_append(&extra_cc, value);
 624                 return 0;
 625         }
 626         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff") ||
 627             !strcmp(var, "color.ui")) {
 628                 return 0;
 629         }
 630         if (!strcmp(var, "format.numbered")) {
 631                 if (value && !strcasecmp(value, "auto")) {
 632                         auto_number = 1;
 633                         return 0;
 634                 }
 635                 numbered = git_config_bool(var, value);
 636                 auto_number = auto_number && numbered;
 637                 return 0;
 638         }
 639         if (!strcmp(var, "format.attach")) {
 640                 if (value && *value)
 641                         default_attach = xstrdup(value);
 642                 else
 643                         default_attach = xstrdup(git_version_string);
 644                 return 0;
 645         }
 646         if (!strcmp(var, "format.thread")) {
 647                 if (value && !strcasecmp(value, "deep")) {
 648                         thread = THREAD_DEEP;
 649                         return 0;
 650                 }
 651                 if (value && !strcasecmp(value, "shallow")) {
 652                         thread = THREAD_SHALLOW;
 653                         return 0;
 654                 }
 655                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
 656                 return 0;
 657         }
 658         if (!strcmp(var, "format.signoff")) {
 659                 do_signoff = git_config_bool(var, value);
 660                 return 0;
 661         }
 662         if (!strcmp(var, "format.signature"))
 663                 return git_config_string(&signature, var, value);
 664
 665         return git_log_config(var, value, cb);
 666 }
 667
 668 static FILE *realstdout = NULL;
 669 static const char *output_directory = NULL;
 670 static int outdir_offset;
 671
 672 static int reopen_stdout(struct commit *commit, const char *subject,
 673                          struct rev_info *rev, int quiet)
 674 {
 675         struct strbuf filename = STRBUF_INIT;
 676         int suffix_len = strlen(fmt_patch_suffix) + 1;
 677
 678         if (output_directory) {
 679                 strbuf_addstr(&filename, output_directory);
 680                 if (filename.len >=
 681                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
 682                         return error(_("name of output directory is too long"));
 683                 if (filename.buf[filename.len - 1] != '/')
 684                         strbuf_addch(&filename, '/');
 685         }
 686
 687         get_patch_filename(commit, subject, rev->nr, fmt_patch_suffix, &filename);
 688
 689         if (!quiet)
 690                 fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
 691
 692         if (freopen(filename.buf, "w", stdout) == NULL)
 693                 return error(_("Cannot open patch file %s"), filename.buf);
 694
 695         strbuf_release(&filename);
 696         return 0;
 697 }
 698
 699 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids, const char *prefix)
 700 {
 701         struct rev_info check_rev;
 702         struct commit *commit;
 703         struct object *o1, *o2;
 704         unsigned flags1, flags2;
 705
 706         if (rev->pending.nr != 2)
 707                 die(_("Need exactly one range."));
 708
 709         o1 = rev->pending.objects[0].item;
 710         flags1 = o1->flags;
 711         o2 = rev->pending.objects[1].item;
 712         flags2 = o2->flags;
 713
 714         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
 715                 die(_("Not a range."));
 716
 717         init_patch_ids(ids);
 718
 719         /* given a range a..b get all patch ids for b..a */
 720         init_revisions(&check_rev, prefix);
 721         o1->flags ^= UNINTERESTING;
 722         o2->flags ^= UNINTERESTING;
 723         add_pending_object(&check_rev, o1, "o1");
 724         add_pending_object(&check_rev, o2, "o2");
 725         if (prepare_revision_walk(&check_rev))
 726                 die(_("revision walk setup failed"));
 727
 728         while ((commit = get_revision(&check_rev)) != NULL) {
 729                 /* ignore merges */
 730                 if (commit->parents && commit->parents->next)
 731                         continue;
 732
 733                 add_commit_patch_id(commit, ids);
 734         }
 735
 736         /* reset for next revision walk */
 737         clear_commit_marks((struct commit *)o1,
 738                         SEEN | UNINTERESTING | SHOWN | ADDED);
 739         clear_commit_marks((struct commit *)o2,
 740                         SEEN | UNINTERESTING | SHOWN | ADDED);
 741         o1->flags = flags1;
 742         o2->flags = flags2;
 743 }
 744
 745 static void gen_message_id(struct rev_info *info, char *base)
 746 {
 747         struct strbuf buf = STRBUF_INIT;
 748         strbuf_addf(&buf, "%s.%lu.git.%s", base,
 749                     (unsigned long) time(NULL),
 750                     git_committer_info(IDENT_NO_NAME|IDENT_NO_DATE|IDENT_STRICT));
 751         info->message_id = strbuf_detach(&buf, NULL);
 752 }
 753
 754 static void print_signature(void)
 755 {
 756         if (signature && *signature)
 757                 printf("-- \n%s\n\n", signature);
 758 }
 759
 760 static void add_branch_description(struct strbuf *buf, const char *branch_name)
 761 {
 762         struct strbuf desc = STRBUF_INIT;
 763         if (!branch_name || !*branch_name)
 764                 return;
 765         read_branch_desc(&desc, branch_name);
 766         if (desc.len) {
 767                 strbuf_addch(buf, '\n');
 768                 strbuf_add(buf, desc.buf, desc.len);
 769                 strbuf_addch(buf, '\n');
 770         }
 771 }
 772
 773 static void make_cover_letter(struct rev_info *rev, int use_stdout,
 774                               int numbered, int numbered_files,
 775                               struct commit *origin,
 776                               int nr, struct commit **list, struct commit *head,
 777                               const char *branch_name,
 778                               int quiet)
 779 {
 780         const char *committer;
 781         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
 782         const char *msg;
 783         struct shortlog log;
 784         struct strbuf sb = STRBUF_INIT;
 785         int i;
 786         const char *encoding = "UTF-8";
 787         struct diff_options opts;
 788         int need_8bit_cte = 0;
 789         struct pretty_print_context pp = {0};
 790
 791         if (rev->commit_format != CMIT_FMT_EMAIL)
 792                 die(_("Cover letter needs email format"));
 793
 794         committer = git_committer_info(0);
 795
 796         if (!use_stdout &&
 797             reopen_stdout(NULL, numbered_files ? NULL : "cover-letter", rev, quiet))
 798                 return;
 799
 800         log_write_email_headers(rev, head, &pp.subject, &pp.after_subject,
 801                                 &need_8bit_cte);
 802
 803         for (i = 0; !need_8bit_cte && i < nr; i++)
 804                 if (has_non_ascii(list[i]->buffer))
 805                         need_8bit_cte = 1;
 806
 807         msg = body;
 808         pp.fmt = CMIT_FMT_EMAIL;
 809         pp.date_mode = DATE_RFC2822;
 810         pp_user_info(&pp, NULL, &sb, committer, encoding);
 811         pp_title_line(&pp, &msg, &sb, encoding, need_8bit_cte);
 812         pp_remainder(&pp, &msg, &sb, 0);
 813         add_branch_description(&sb, branch_name);
 814         printf("%s\n", sb.buf);
 815
 816         strbuf_release(&sb);
 817
 818         shortlog_init(&log);
 819         log.wrap_lines = 1;
 820         log.wrap = 72;
 821         log.in1 = 2;
 822         log.in2 = 4;
 823         for (i = 0; i < nr; i++)
 824                 shortlog_add_commit(&log, list[i]);
 825
 826         shortlog_output(&log);
 827
 828         /*
 829          * We can only do diffstat with a unique reference point
 830          */
 831         if (!origin)
 832                 return;
 833
 834         memcpy(&opts, &rev->diffopt, sizeof(opts));
 835         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
 836
 837         diff_setup_done(&opts);
 838
 839         diff_tree_sha1(origin->tree->object.sha1,
 840                        head->tree->object.sha1,
 841                        "", &opts);
 842         diffcore_std(&opts);
 843         diff_flush(&opts);
 844
 845         printf("\n");
 846         print_signature();
 847 }
 848
 849 static const char *clean_message_id(const char *msg_id)
 850 {
 851         char ch;
 852         const char *a, *z, *m;
 853
 854         m = msg_id;
 855         while ((ch = *m) && (isspace(ch) || (ch == '<')))
 856                 m++;
 857         a = m;
 858         z = NULL;
 859         while ((ch = *m)) {
 860                 if (!isspace(ch) && (ch != '>'))
 861                         z = m;
 862                 m++;
 863         }
 864         if (!z)
 865                 die(_("insane in-reply-to: %s"), msg_id);
 866         if (++z == m)
 867                 return a;
 868         return xmemdupz(a, z - a);
 869 }
 870
 871 static const char *set_outdir(const char *prefix, const char *output_directory)
 872 {
 873         if (output_directory && is_absolute_path(output_directory))
 874                 return output_directory;
 875
 876         if (!prefix || !*prefix) {
 877                 if (output_directory)
 878                         return output_directory;
 879                 /* The user did not explicitly ask for "./" */
 880                 outdir_offset = 2;
 881                 return "./";
 882         }
 883
 884         outdir_offset = strlen(prefix);
 885         if (!output_directory)
 886                 return prefix;
 887
 888         return xstrdup(prefix_filename(prefix, outdir_offset,
 889                                        output_directory));
 890 }
 891
 892 static const char * const builtin_format_patch_usage[] = {
 893         "git format-patch [options] [<since> | <revision range>]",
 894         NULL
 895 };
 896
 897 static int keep_subject = 0;
 898
 899 static int keep_callback(const struct option *opt, const char *arg, int unset)
 900 {
 901         ((struct rev_info *)opt->value)->total = -1;
 902         keep_subject = 1;
 903         return 0;
 904 }
 905
 906 static int subject_prefix = 0;
 907
 908 static int subject_prefix_callback(const struct option *opt, const char *arg,
 909                             int unset)
 910 {
 911         subject_prefix = 1;
 912         ((struct rev_info *)opt->value)->subject_prefix = arg;
 913         return 0;
 914 }
 915
 916 static int numbered_cmdline_opt = 0;
 917
 918 static int numbered_callback(const struct option *opt, const char *arg,
 919                              int unset)
 920 {
 921         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
 922         if (unset)
 923                 auto_number =  0;
 924         return 0;
 925 }
 926
 927 static int no_numbered_callback(const struct option *opt, const char *arg,
 928                                 int unset)
 929 {
 930         return numbered_callback(opt, arg, 1);
 931 }
 932
 933 static int output_directory_callback(const struct option *opt, const char *arg,
 934                               int unset)
 935 {
 936         const char **dir = (const char **)opt->value;
 937         if (*dir)
 938                 die(_("Two output directories?"));
 939         *dir = arg;
 940         return 0;
 941 }
 942
 943 static int thread_callback(const struct option *opt, const char *arg, int unset)
 944 {
 945         int *thread = (int *)opt->value;
 946         if (unset)
 947                 *thread = 0;
 948         else if (!arg || !strcmp(arg, "shallow"))
 949                 *thread = THREAD_SHALLOW;
 950         else if (!strcmp(arg, "deep"))
 951                 *thread = THREAD_DEEP;
 952         else
 953                 return 1;
 954         return 0;
 955 }
 956
 957 static int attach_callback(const struct option *opt, const char *arg, int unset)
 958 {
 959         struct rev_info *rev = (struct rev_info *)opt->value;
 960         if (unset)
 961                 rev->mime_boundary = NULL;
 962         else if (arg)
 963                 rev->mime_boundary = arg;
 964         else
 965                 rev->mime_boundary = git_version_string;
 966         rev->no_inline = unset ? 0 : 1;
 967         return 0;
 968 }
 969
 970 static int inline_callback(const struct option *opt, const char *arg, int unset)
 971 {
 972         struct rev_info *rev = (struct rev_info *)opt->value;
 973         if (unset)
 974                 rev->mime_boundary = NULL;
 975         else if (arg)
 976                 rev->mime_boundary = arg;
 977         else
 978                 rev->mime_boundary = git_version_string;
 979         rev->no_inline = 0;
 980         return 0;
 981 }
 982
 983 static int header_callback(const struct option *opt, const char *arg, int unset)
 984 {
 985         if (unset) {
 986                 string_list_clear(&extra_hdr, 0);
 987                 string_list_clear(&extra_to, 0);
 988                 string_list_clear(&extra_cc, 0);
 989         } else {
 990             add_header(arg);
 991         }
 992         return 0;
 993 }
 994
 995 static int to_callback(const struct option *opt, const char *arg, int unset)
 996 {
 997         if (unset)
 998                 string_list_clear(&extra_to, 0);
 999         else
1000                 string_list_append(&extra_to, arg);
1001         return 0;
1002 }
1003
1004 static int cc_callback(const struct option *opt, const char *arg, int unset)
1005 {
1006         if (unset)
1007                 string_list_clear(&extra_cc, 0);
1008         else
1009                 string_list_append(&extra_cc, arg);
1010         return 0;
1011 }
1012
1013 static char *find_branch_name(struct rev_info *rev)
1014 {
1015         int i, positive = -1;
1016         unsigned char branch_sha1[20];
1017         struct strbuf buf = STRBUF_INIT;
1018         const char *branch;
1019
1020         for (i = 0; i < rev->cmdline.nr; i++) {
1021                 if (rev->cmdline.rev[i].flags & UNINTERESTING)
1022                         continue;
1023                 if (positive < 0)
1024                         positive = i;
1025                 else
1026                         return NULL;
1027         }
1028         if (positive < 0)
1029                 return NULL;
1030         strbuf_addf(&buf, "refs/heads/%s", rev->cmdline.rev[positive].name);
1031         branch = resolve_ref_unsafe(buf.buf, branch_sha1, 1, NULL);
1032         if (!branch ||
1033             prefixcmp(branch, "refs/heads/") ||
1034             hashcmp(rev->cmdline.rev[positive].item->sha1, branch_sha1))
1035                 branch = NULL;
1036         strbuf_release(&buf);
1037         if (branch)
1038                 return xstrdup(rev->cmdline.rev[positive].name);
1039         return NULL;
1040 }
1041
1042 int cmd_format_patch(int argc, const char **argv, const char *prefix)
1043 {
1044         struct commit *commit;
1045         struct commit **list = NULL;
1046         struct rev_info rev;
1047         struct setup_revision_opt s_r_opt;
1048         int nr = 0, total, i;
1049         int use_stdout = 0;
1050         int start_number = -1;
1051         int numbered_files = 0;         /* _just_ numbers */
1052         int ignore_if_in_upstream = 0;
1053         int cover_letter = 0;
1054         int boundary_count = 0;
1055         int no_binary_diff = 0;
1056         struct commit *origin = NULL, *head = NULL;
1057         const char *in_reply_to = NULL;
1058         struct patch_ids ids;
1059         char *add_signoff = NULL;
1060         struct strbuf buf = STRBUF_INIT;
1061         int use_patch_format = 0;
1062         int quiet = 0;
1063         char *branch_name = NULL;
1064         const struct option builtin_format_patch_options[] = {
1065                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
1066                             "use [PATCH n/m] even with a single patch",
1067                             PARSE_OPT_NOARG, numbered_callback },
1068                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
1069                             "use [PATCH] even with multiple patches",
1070                             PARSE_OPT_NOARG, no_numbered_callback },
1071                 OPT_BOOLEAN('s', "signoff", &do_signoff, "add Signed-off-by:"),
1072                 OPT_BOOLEAN(0, "stdout", &use_stdout,
1073                             "print patches to standard out"),
1074                 OPT_BOOLEAN(0, "cover-letter", &cover_letter,
1075                             "generate a cover letter"),
1076                 OPT_BOOLEAN(0, "numbered-files", &numbered_files,
1077                             "use simple number sequence for output file names"),
1078                 OPT_STRING(0, "suffix", &fmt_patch_suffix, "sfx",
1079                             "use <sfx> instead of '.patch'"),
1080                 OPT_INTEGER(0, "start-number", &start_number,
1081                             "start numbering patches at <n> instead of 1"),
1082                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, "prefix",
1083                             "Use [<prefix>] instead of [PATCH]",
1084                             PARSE_OPT_NONEG, subject_prefix_callback },
1085                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
1086                             "dir", "store resulting files in <dir>",
1087                             PARSE_OPT_NONEG, output_directory_callback },
1088                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
1089                             "don't strip/add [PATCH]",
1090                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
1091                 OPT_BOOLEAN(0, "no-binary", &no_binary_diff,
1092                             "don't output binary diffs"),
1093                 OPT_BOOLEAN(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
1094                             "don't include a patch matching a commit upstream"),
1095                 { OPTION_BOOLEAN, 'p', "no-stat", &use_patch_format, NULL,
1096                   "show patch format instead of default (patch + stat)",
1097                   PARSE_OPT_NONEG | PARSE_OPT_NOARG },
1098                 OPT_GROUP("Messaging"),
1099                 { OPTION_CALLBACK, 0, "add-header", NULL, "header",
1100                             "add email header", 0, header_callback },
1101                 { OPTION_CALLBACK, 0, "to", NULL, "email", "add To: header",
1102                             0, to_callback },
1103                 { OPTION_CALLBACK, 0, "cc", NULL, "email", "add Cc: header",
1104                             0, cc_callback },
1105                 OPT_STRING(0, "in-reply-to", &in_reply_to, "message-id",
1106                             "make first mail a reply to <message-id>"),
1107                 { OPTION_CALLBACK, 0, "attach", &rev, "boundary",
1108                             "attach the patch", PARSE_OPT_OPTARG,
1109                             attach_callback },
1110                 { OPTION_CALLBACK, 0, "inline", &rev, "boundary",
1111                             "inline the patch",
1112                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
1113                             inline_callback },
1114                 { OPTION_CALLBACK, 0, "thread", &thread, "style",
1115                             "enable message threading, styles: shallow, deep",
1116                             PARSE_OPT_OPTARG, thread_callback },
1117                 OPT_STRING(0, "signature", &signature, "signature",
1118                             "add a signature"),
1119                 OPT_BOOLEAN(0, "quiet", &quiet,
1120                             "don't print the patch filenames"),
1121                 OPT_END()
1122         };
1123
1124         extra_hdr.strdup_strings = 1;
1125         extra_to.strdup_strings = 1;
1126         extra_cc.strdup_strings = 1;
1127         git_config(git_format_config, NULL);
1128         init_revisions(&rev, prefix);
1129         rev.commit_format = CMIT_FMT_EMAIL;
1130         rev.verbose_header = 1;
1131         rev.diff = 1;
1132         rev.max_parents = 1;
1133         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
1134         rev.subject_prefix = fmt_patch_subject_prefix;
1135         memset(&s_r_opt, 0, sizeof(s_r_opt));
1136         s_r_opt.def = "HEAD";
1137         s_r_opt.revarg_opt = REVARG_COMMITTISH;
1138
1139         if (default_attach) {
1140                 rev.mime_boundary = default_attach;
1141                 rev.no_inline = 1;
1142         }
1143
1144         /*
1145          * Parse the arguments before setup_revisions(), or something
1146          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1147          * possibly a valid SHA1.
1148          */
1149         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1150                              builtin_format_patch_usage,
1151                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1152                              PARSE_OPT_KEEP_DASHDASH);
1153
1154         if (do_signoff) {
1155                 const char *committer;
1156                 const char *endpos;
1157                 committer = git_committer_info(IDENT_STRICT);
1158                 endpos = strchr(committer, '>');
1159                 if (!endpos)
1160                         die(_("bogus committer info %s"), committer);
1161                 add_signoff = xmemdupz(committer, endpos - committer + 1);
1162         }
1163
1164         for (i = 0; i < extra_hdr.nr; i++) {
1165                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1166                 strbuf_addch(&buf, '\n');
1167         }
1168
1169         if (extra_to.nr)
1170                 strbuf_addstr(&buf, "To: ");
1171         for (i = 0; i < extra_to.nr; i++) {
1172                 if (i)
1173                         strbuf_addstr(&buf, "    ");
1174                 strbuf_addstr(&buf, extra_to.items[i].string);
1175                 if (i + 1 < extra_to.nr)
1176                         strbuf_addch(&buf, ',');
1177                 strbuf_addch(&buf, '\n');
1178         }
1179
1180         if (extra_cc.nr)
1181                 strbuf_addstr(&buf, "Cc: ");
1182         for (i = 0; i < extra_cc.nr; i++) {
1183                 if (i)
1184                         strbuf_addstr(&buf, "    ");
1185                 strbuf_addstr(&buf, extra_cc.items[i].string);
1186                 if (i + 1 < extra_cc.nr)
1187                         strbuf_addch(&buf, ',');
1188                 strbuf_addch(&buf, '\n');
1189         }
1190
1191         rev.extra_headers = strbuf_detach(&buf, NULL);
1192
1193         if (start_number < 0)
1194                 start_number = 1;
1195
1196         /*
1197          * If numbered is set solely due to format.numbered in config,
1198          * and it would conflict with --keep-subject (-k) from the
1199          * command line, reset "numbered".
1200          */
1201         if (numbered && keep_subject && !numbered_cmdline_opt)
1202                 numbered = 0;
1203
1204         if (numbered && keep_subject)
1205                 die (_("-n and -k are mutually exclusive."));
1206         if (keep_subject && subject_prefix)
1207                 die (_("--subject-prefix and -k are mutually exclusive."));
1208         rev.preserve_subject = keep_subject;
1209
1210         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1211         if (argc > 1)
1212                 die (_("unrecognized argument: %s"), argv[1]);
1213
1214         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1215                 die(_("--name-only does not make sense"));
1216         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1217                 die(_("--name-status does not make sense"));
1218         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1219                 die(_("--check does not make sense"));
1220
1221         if (!use_patch_format &&
1222                 (!rev.diffopt.output_format ||
1223                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1224                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1225
1226         /* Always generate a patch */
1227         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1228
1229         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1230                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1231
1232         if (rev.show_notes)
1233                 init_display_notes(&rev.notes_opt);
1234
1235         if (!use_stdout)
1236                 output_directory = set_outdir(prefix, output_directory);
1237         else
1238                 setup_pager();
1239
1240         if (output_directory) {
1241                 if (use_stdout)
1242                         die(_("standard output, or directory, which one?"));
1243                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1244                         die_errno(_("Could not create directory '%s'"),
1245                                   output_directory);
1246         }
1247
1248         if (rev.pending.nr == 1) {
1249                 if (rev.max_count < 0 && !rev.show_root_diff) {
1250                         /*
1251                          * This is traditional behaviour of "git format-patch
1252                          * origin" that prepares what the origin side still
1253                          * does not have.
1254                          */
1255                         unsigned char sha1[20];
1256                         const char *ref;
1257
1258                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1259                         add_head_to_pending(&rev);
1260                         ref = resolve_ref_unsafe("HEAD", sha1, 1, NULL);
1261                         if (ref && !prefixcmp(ref, "refs/heads/"))
1262                                 branch_name = xstrdup(ref + strlen("refs/heads/"));
1263                         else
1264                                 branch_name = xstrdup(""); /* no branch */
1265                 }
1266                 /*
1267                  * Otherwise, it is "format-patch -22 HEAD", and/or
1268                  * "format-patch --root HEAD".  The user wants
1269                  * get_revision() to do the usual traversal.
1270                  */
1271         }
1272
1273         /*
1274          * We cannot move this anywhere earlier because we do want to
1275          * know if --root was given explicitly from the command line.
1276          */
1277         rev.show_root_diff = 1;
1278
1279         if (cover_letter) {
1280                 /*
1281                  * NEEDSWORK:randomly pick one positive commit to show
1282                  * diffstat; this is often the tip and the command
1283                  * happens to do the right thing in most cases, but a
1284                  * complex command like "--cover-letter a b c ^bottom"
1285                  * picks "c" and shows diffstat between bottom..c
1286                  * which may not match what the series represents at
1287                  * all and totally broken.
1288                  */
1289                 int i;
1290                 for (i = 0; i < rev.pending.nr; i++) {
1291                         struct object *o = rev.pending.objects[i].item;
1292                         if (!(o->flags & UNINTERESTING))
1293                                 head = (struct commit *)o;
1294                 }
1295                 /* There is nothing to show; it is not an error, though. */
1296                 if (!head)
1297                         return 0;
1298                 if (!branch_name)
1299                         branch_name = find_branch_name(&rev);
1300         }
1301
1302         if (ignore_if_in_upstream) {
1303                 /* Don't say anything if head and upstream are the same. */
1304                 if (rev.pending.nr == 2) {
1305                         struct object_array_entry *o = rev.pending.objects;
1306                         if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1307                                 return 0;
1308                 }
1309                 get_patch_ids(&rev, &ids, prefix);
1310         }
1311
1312         if (!use_stdout)
1313                 realstdout = xfdopen(xdup(1), "w");
1314
1315         if (prepare_revision_walk(&rev))
1316                 die(_("revision walk setup failed"));
1317         rev.boundary = 1;
1318         while ((commit = get_revision(&rev)) != NULL) {
1319                 if (commit->object.flags & BOUNDARY) {
1320                         boundary_count++;
1321                         origin = (boundary_count == 1) ? commit : NULL;
1322                         continue;
1323                 }
1324
1325                 if (ignore_if_in_upstream &&
1326                                 has_commit_patch_id(commit, &ids))
1327                         continue;
1328
1329                 nr++;
1330                 list = xrealloc(list, nr * sizeof(list[0]));
1331                 list[nr - 1] = commit;
1332         }
1333         total = nr;
1334         if (!keep_subject && auto_number && total > 1)
1335                 numbered = 1;
1336         if (numbered)
1337                 rev.total = total + start_number - 1;
1338         if (in_reply_to || thread || cover_letter)
1339                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1340         if (in_reply_to) {
1341                 const char *msgid = clean_message_id(in_reply_to);
1342                 string_list_append(rev.ref_message_ids, msgid);
1343         }
1344         rev.numbered_files = numbered_files;
1345         rev.patch_suffix = fmt_patch_suffix;
1346         if (cover_letter) {
1347                 if (thread)
1348                         gen_message_id(&rev, "cover");
1349                 make_cover_letter(&rev, use_stdout, numbered, numbered_files,
1350                                   origin, nr, list, head, branch_name, quiet);
1351                 total++;
1352                 start_number--;
1353         }
1354         rev.add_signoff = add_signoff;
1355         while (0 <= --nr) {
1356                 int shown;
1357                 commit = list[nr];
1358                 rev.nr = total - nr + (start_number - 1);
1359                 /* Make the second and subsequent mails replies to the first */
1360                 if (thread) {
1361                         /* Have we already had a message ID? */
1362                         if (rev.message_id) {
1363                                 /*
1364                                  * For deep threading: make every mail
1365                                  * a reply to the previous one, no
1366                                  * matter what other options are set.
1367                                  *
1368                                  * For shallow threading:
1369                                  *
1370                                  * Without --cover-letter and
1371                                  * --in-reply-to, make every mail a
1372                                  * reply to the one before.
1373                                  *
1374                                  * With --in-reply-to but no
1375                                  * --cover-letter, make every mail a
1376                                  * reply to the <reply-to>.
1377                                  *
1378                                  * With --cover-letter, make every
1379                                  * mail but the cover letter a reply
1380                                  * to the cover letter.  The cover
1381                                  * letter is a reply to the
1382                                  * --in-reply-to, if specified.
1383                                  */
1384                                 if (thread == THREAD_SHALLOW
1385                                     && rev.ref_message_ids->nr > 0
1386                                     && (!cover_letter || rev.nr > 1))
1387                                         free(rev.message_id);
1388                                 else
1389                                         string_list_append(rev.ref_message_ids,
1390                                                            rev.message_id);
1391                         }
1392                         gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
1393                 }
1394
1395                 if (!use_stdout &&
1396                     reopen_stdout(numbered_files ? NULL : commit, NULL, &rev, quiet))
1397                         die(_("Failed to create output files"));
1398                 shown = log_tree_commit(&rev, commit);
1399                 free(commit->buffer);
1400                 commit->buffer = NULL;
1401
1402                 /* We put one extra blank line between formatted
1403                  * patches and this flag is used by log-tree code
1404                  * to see if it needs to emit a LF before showing
1405                  * the log; when using one file per patch, we do
1406                  * not want the extra blank line.
1407                  */
1408                 if (!use_stdout)
1409                         rev.shown_one = 0;
1410                 if (shown) {
1411                         if (rev.mime_boundary)
1412                                 printf("\n--%s%s--\n\n\n",
1413                                        mime_boundary_leader,
1414                                        rev.mime_boundary);
1415                         else
1416                                 print_signature();
1417                 }
1418                 if (!use_stdout)
1419                         fclose(stdout);
1420         }
1421         free(list);
1422         free(branch_name);
1423         string_list_clear(&extra_to, 0);
1424         string_list_clear(&extra_cc, 0);
1425         string_list_clear(&extra_hdr, 0);
1426         if (ignore_if_in_upstream)
1427                 free_patch_ids(&ids);
1428         return 0;
1429 }
1430
1431 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1432 {
1433         unsigned char sha1[20];
1434         if (get_sha1(arg, sha1) == 0) {
1435                 struct commit *commit = lookup_commit_reference(sha1);
1436                 if (commit) {
1437                         commit->object.flags |= flags;
1438                         add_pending_object(revs, &commit->object, arg);
1439                         return 0;
1440                 }
1441         }
1442         return -1;
1443 }
1444
1445 static const char * const cherry_usage[] = {
1446         "git cherry [-v] [<upstream> [<head> [<limit>]]]",
1447         NULL
1448 };
1449
1450 static void print_commit(char sign, struct commit *commit, int verbose,
1451                          int abbrev)
1452 {
1453         if (!verbose) {
1454                 printf("%c %s\n", sign,
1455                        find_unique_abbrev(commit->object.sha1, abbrev));
1456         } else {
1457                 struct strbuf buf = STRBUF_INIT;
1458                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
1459                 printf("%c %s %s\n", sign,
1460                        find_unique_abbrev(commit->object.sha1, abbrev),
1461                        buf.buf);
1462                 strbuf_release(&buf);
1463         }
1464 }
1465
1466 int cmd_cherry(int argc, const char **argv, const char *prefix)
1467 {
1468         struct rev_info revs;
1469         struct patch_ids ids;
1470         struct commit *commit;
1471         struct commit_list *list = NULL;
1472         struct branch *current_branch;
1473         const char *upstream;
1474         const char *head = "HEAD";
1475         const char *limit = NULL;
1476         int verbose = 0, abbrev = 0;
1477
1478         struct option options[] = {
1479                 OPT__ABBREV(&abbrev),
1480                 OPT__VERBOSE(&verbose, "be verbose"),
1481                 OPT_END()
1482         };
1483
1484         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
1485
1486         switch (argc) {
1487         case 3:
1488                 limit = argv[2];
1489                 /* FALLTHROUGH */
1490         case 2:
1491                 head = argv[1];
1492                 /* FALLTHROUGH */
1493         case 1:
1494                 upstream = argv[0];
1495                 break;
1496         default:
1497                 current_branch = branch_get(NULL);
1498                 if (!current_branch || !current_branch->merge
1499                                         || !current_branch->merge[0]
1500                                         || !current_branch->merge[0]->dst) {
1501                         fprintf(stderr, _("Could not find a tracked"
1502                                         " remote branch, please"
1503                                         " specify <upstream> manually.\n"));
1504                         usage_with_options(cherry_usage, options);
1505                 }
1506
1507                 upstream = current_branch->merge[0]->dst;
1508         }
1509
1510         init_revisions(&revs, prefix);
1511         revs.diff = 1;
1512         revs.combine_merges = 0;
1513         revs.ignore_merges = 1;
1514         DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
1515
1516         if (add_pending_commit(head, &revs, 0))
1517                 die(_("Unknown commit %s"), head);
1518         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1519                 die(_("Unknown commit %s"), upstream);
1520
1521         /* Don't say anything if head and upstream are the same. */
1522         if (revs.pending.nr == 2) {
1523                 struct object_array_entry *o = revs.pending.objects;
1524                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1525                         return 0;
1526         }
1527
1528         get_patch_ids(&revs, &ids, prefix);
1529
1530         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1531                 die(_("Unknown commit %s"), limit);
1532
1533         /* reverse the list of commits */
1534         if (prepare_revision_walk(&revs))
1535                 die(_("revision walk setup failed"));
1536         while ((commit = get_revision(&revs)) != NULL) {
1537                 /* ignore merges */
1538                 if (commit->parents && commit->parents->next)
1539                         continue;
1540
1541                 commit_list_insert(commit, &list);
1542         }
1543
1544         while (list) {
1545                 char sign = '+';
1546
1547                 commit = list->item;
1548                 if (has_commit_patch_id(commit, &ids))
1549                         sign = '-';
1550                 print_commit(sign, commit, verbose, abbrev);
1551                 list = list->next;
1552         }
1553
1554         free_patch_ids(&ids);
1555         return 0;
1556 }