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         N_("git log [<options>] [<since>..<until>] [[--] <path>...]\n")
  38         N_("   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, N_("suppress diff output")),
 101                 OPT_BOOLEAN(0, "source", &source, N_("show source")),
 102                 { OPTION_CALLBACK, 0, "decorate", NULL, NULL, N_("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         if (quiet)
 113                 rev->diffopt.output_format |= DIFF_FORMAT_NO_OUTPUT;
 114         argc = setup_revisions(argc, argv, rev, opt);
 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         if (grep_config(var, value, cb) < 0)
 355                 return -1;
 356         return git_diff_ui_config(var, value, cb);
 357 }
 358
 359 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 360 {
 361         struct rev_info rev;
 362         struct setup_revision_opt opt;
 363
 364         init_grep_defaults();
 365         git_config(git_log_config, NULL);
 366
 367         init_revisions(&rev, prefix);
 368         rev.diff = 1;
 369         rev.simplify_history = 0;
 370         memset(&opt, 0, sizeof(opt));
 371         opt.def = "HEAD";
 372         opt.revarg_opt = REVARG_COMMITTISH;
 373         cmd_log_init(argc, argv, prefix, &rev, &opt);
 374         if (!rev.diffopt.output_format)
 375                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
 376         return cmd_log_walk(&rev);
 377 }
 378
 379 static void show_tagger(char *buf, int len, struct rev_info *rev)
 380 {
 381         struct strbuf out = STRBUF_INIT;
 382         struct pretty_print_context pp = {0};
 383
 384         pp.fmt = rev->commit_format;
 385         pp.date_mode = rev->date_mode;
 386         pp_user_info(&pp, "Tagger", &out, buf, get_log_output_encoding());
 387         printf("%s", out.buf);
 388         strbuf_release(&out);
 389 }
 390
 391 static int show_blob_object(const unsigned char *sha1, struct rev_info *rev)
 392 {
 393         fflush(stdout);
 394         return stream_blob_to_fd(1, sha1, NULL, 0);
 395 }
 396
 397 static int show_tag_object(const unsigned char *sha1, struct rev_info *rev)
 398 {
 399         unsigned long size;
 400         enum object_type type;
 401         char *buf = read_sha1_file(sha1, &type, &size);
 402         int offset = 0;
 403
 404         if (!buf)
 405                 return error(_("Could not read object %s"), sha1_to_hex(sha1));
 406
 407         assert(type == OBJ_TAG);
 408         while (offset < size && buf[offset] != '\n') {
 409                 int new_offset = offset + 1;
 410                 while (new_offset < size && buf[new_offset++] != '\n')
 411                         ; /* do nothing */
 412                 if (!prefixcmp(buf + offset, "tagger "))
 413                         show_tagger(buf + offset + 7,
 414                                     new_offset - offset - 7, rev);
 415                 offset = new_offset;
 416         }
 417
 418         if (offset < size)
 419                 fwrite(buf + offset, size - offset, 1, stdout);
 420         free(buf);
 421         return 0;
 422 }
 423
 424 static int show_tree_object(const unsigned char *sha1,
 425                 const char *base, int baselen,
 426                 const char *pathname, unsigned mode, int stage, void *context)
 427 {
 428         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
 429         return 0;
 430 }
 431
 432 static void show_rev_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
 433 {
 434         if (rev->ignore_merges) {
 435                 /* There was no "-m" on the command line */
 436                 rev->ignore_merges = 0;
 437                 if (!rev->first_parent_only && !rev->combine_merges) {
 438                         /* No "--first-parent", "-c", nor "--cc" */
 439                         rev->combine_merges = 1;
 440                         rev->dense_combined_merges = 1;
 441                 }
 442         }
 443         if (!rev->diffopt.output_format)
 444                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
 445 }
 446
 447 int cmd_show(int argc, const char **argv, const char *prefix)
 448 {
 449         struct rev_info rev;
 450         struct object_array_entry *objects;
 451         struct setup_revision_opt opt;
 452         struct pathspec match_all;
 453         int i, count, ret = 0;
 454
 455         init_grep_defaults();
 456         git_config(git_log_config, NULL);
 457
 458         init_pathspec(&match_all, NULL);
 459         init_revisions(&rev, prefix);
 460         rev.diff = 1;
 461         rev.always_show_header = 1;
 462         rev.no_walk = REVISION_WALK_NO_WALK_SORTED;
 463         rev.diffopt.stat_width = -1;    /* Scale to real terminal size */
 464
 465         memset(&opt, 0, sizeof(opt));
 466         opt.def = "HEAD";
 467         opt.tweak = show_rev_tweak_rev;
 468         cmd_log_init(argc, argv, prefix, &rev, &opt);
 469
 470         if (!rev.no_walk)
 471                 return cmd_log_walk(&rev);
 472
 473         count = rev.pending.nr;
 474         objects = rev.pending.objects;
 475         for (i = 0; i < count && !ret; i++) {
 476                 struct object *o = objects[i].item;
 477                 const char *name = objects[i].name;
 478                 switch (o->type) {
 479                 case OBJ_BLOB:
 480                         ret = show_blob_object(o->sha1, NULL);
 481                         break;
 482                 case OBJ_TAG: {
 483                         struct tag *t = (struct tag *)o;
 484
 485                         if (rev.shown_one)
 486                                 putchar('\n');
 487                         printf("%stag %s%s\n",
 488                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 489                                         t->tag,
 490                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 491                         ret = show_tag_object(o->sha1, &rev);
 492                         rev.shown_one = 1;
 493                         if (ret)
 494                                 break;
 495                         o = parse_object(t->tagged->sha1);
 496                         if (!o)
 497                                 ret = error(_("Could not read object %s"),
 498                                             sha1_to_hex(t->tagged->sha1));
 499                         objects[i].item = o;
 500                         i--;
 501                         break;
 502                 }
 503                 case OBJ_TREE:
 504                         if (rev.shown_one)
 505                                 putchar('\n');
 506                         printf("%stree %s%s\n\n",
 507                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 508                                         name,
 509                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 510                         read_tree_recursive((struct tree *)o, "", 0, 0, &match_all,
 511                                         show_tree_object, NULL);
 512                         rev.shown_one = 1;
 513                         break;
 514                 case OBJ_COMMIT:
 515                         rev.pending.nr = rev.pending.alloc = 0;
 516                         rev.pending.objects = NULL;
 517                         add_object_array(o, name, &rev.pending);
 518                         ret = cmd_log_walk(&rev);
 519                         break;
 520                 default:
 521                         ret = error(_("Unknown type: %d"), o->type);
 522                 }
 523         }
 524         free(objects);
 525         return ret;
 526 }
 527
 528 /*
 529  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
 530  */
 531 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
 532 {
 533         struct rev_info rev;
 534         struct setup_revision_opt opt;
 535
 536         init_grep_defaults();
 537         git_config(git_log_config, NULL);
 538
 539         init_revisions(&rev, prefix);
 540         init_reflog_walk(&rev.reflog_info);
 541         rev.verbose_header = 1;
 542         memset(&opt, 0, sizeof(opt));
 543         opt.def = "HEAD";
 544         cmd_log_init_defaults(&rev);
 545         rev.abbrev_commit = 1;
 546         rev.commit_format = CMIT_FMT_ONELINE;
 547         rev.use_terminator = 1;
 548         rev.always_show_header = 1;
 549         cmd_log_init_finish(argc, argv, prefix, &rev, &opt);
 550
 551         return cmd_log_walk(&rev);
 552 }
 553
 554 int cmd_log(int argc, const char **argv, const char *prefix)
 555 {
 556         struct rev_info rev;
 557         struct setup_revision_opt opt;
 558
 559         init_grep_defaults();
 560         git_config(git_log_config, NULL);
 561
 562         init_revisions(&rev, prefix);
 563         rev.always_show_header = 1;
 564         memset(&opt, 0, sizeof(opt));
 565         opt.def = "HEAD";
 566         opt.revarg_opt = REVARG_COMMITTISH;
 567         cmd_log_init(argc, argv, prefix, &rev, &opt);
 568         return cmd_log_walk(&rev);
 569 }
 570
 571 /* format-patch */
 572
 573 static const char *fmt_patch_suffix = ".patch";
 574 static int numbered = 0;
 575 static int auto_number = 1;
 576
 577 static char *default_attach = NULL;
 578
 579 static struct string_list extra_hdr;
 580 static struct string_list extra_to;
 581 static struct string_list extra_cc;
 582
 583 static void add_header(const char *value)
 584 {
 585         struct string_list_item *item;
 586         int len = strlen(value);
 587         while (len && value[len - 1] == '\n')
 588                 len--;
 589
 590         if (!strncasecmp(value, "to: ", 4)) {
 591                 item = string_list_append(&extra_to, value + 4);
 592                 len -= 4;
 593         } else if (!strncasecmp(value, "cc: ", 4)) {
 594                 item = string_list_append(&extra_cc, value + 4);
 595                 len -= 4;
 596         } else {
 597                 item = string_list_append(&extra_hdr, value);
 598         }
 599
 600         item->string[len] = '\0';
 601 }
 602
 603 #define THREAD_SHALLOW 1
 604 #define THREAD_DEEP 2
 605 static int thread;
 606 static int do_signoff;
 607 static const char *signature = git_version_string;
 608
 609 static int git_format_config(const char *var, const char *value, void *cb)
 610 {
 611         if (!strcmp(var, "format.headers")) {
 612                 if (!value)
 613                         die(_("format.headers without value"));
 614                 add_header(value);
 615                 return 0;
 616         }
 617         if (!strcmp(var, "format.suffix"))
 618                 return git_config_string(&fmt_patch_suffix, var, value);
 619         if (!strcmp(var, "format.to")) {
 620                 if (!value)
 621                         return config_error_nonbool(var);
 622                 string_list_append(&extra_to, value);
 623                 return 0;
 624         }
 625         if (!strcmp(var, "format.cc")) {
 626                 if (!value)
 627                         return config_error_nonbool(var);
 628                 string_list_append(&extra_cc, value);
 629                 return 0;
 630         }
 631         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff") ||
 632             !strcmp(var, "color.ui")) {
 633                 return 0;
 634         }
 635         if (!strcmp(var, "format.numbered")) {
 636                 if (value && !strcasecmp(value, "auto")) {
 637                         auto_number = 1;
 638                         return 0;
 639                 }
 640                 numbered = git_config_bool(var, value);
 641                 auto_number = auto_number && numbered;
 642                 return 0;
 643         }
 644         if (!strcmp(var, "format.attach")) {
 645                 if (value && *value)
 646                         default_attach = xstrdup(value);
 647                 else
 648                         default_attach = xstrdup(git_version_string);
 649                 return 0;
 650         }
 651         if (!strcmp(var, "format.thread")) {
 652                 if (value && !strcasecmp(value, "deep")) {
 653                         thread = THREAD_DEEP;
 654                         return 0;
 655                 }
 656                 if (value && !strcasecmp(value, "shallow")) {
 657                         thread = THREAD_SHALLOW;
 658                         return 0;
 659                 }
 660                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
 661                 return 0;
 662         }
 663         if (!strcmp(var, "format.signoff")) {
 664                 do_signoff = git_config_bool(var, value);
 665                 return 0;
 666         }
 667         if (!strcmp(var, "format.signature"))
 668                 return git_config_string(&signature, var, value);
 669
 670         return git_log_config(var, value, cb);
 671 }
 672
 673 static FILE *realstdout = NULL;
 674 static const char *output_directory = NULL;
 675 static int outdir_offset;
 676
 677 static int reopen_stdout(struct commit *commit, const char *subject,
 678                          struct rev_info *rev, int quiet)
 679 {
 680         struct strbuf filename = STRBUF_INIT;
 681         int suffix_len = strlen(rev->patch_suffix) + 1;
 682
 683         if (output_directory) {
 684                 strbuf_addstr(&filename, output_directory);
 685                 if (filename.len >=
 686                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
 687                         return error(_("name of output directory is too long"));
 688                 if (filename.buf[filename.len - 1] != '/')
 689                         strbuf_addch(&filename, '/');
 690         }
 691
 692         if (rev->numbered_files)
 693                 strbuf_addf(&filename, "%d", rev->nr);
 694         else if (commit)
 695                 fmt_output_commit(&filename, commit, rev);
 696         else
 697                 fmt_output_subject(&filename, subject, rev);
 698
 699         if (!quiet)
 700                 fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
 701
 702         if (freopen(filename.buf, "w", stdout) == NULL)
 703                 return error(_("Cannot open patch file %s"), filename.buf);
 704
 705         strbuf_release(&filename);
 706         return 0;
 707 }
 708
 709 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids)
 710 {
 711         struct rev_info check_rev;
 712         struct commit *commit;
 713         struct object *o1, *o2;
 714         unsigned flags1, flags2;
 715
 716         if (rev->pending.nr != 2)
 717                 die(_("Need exactly one range."));
 718
 719         o1 = rev->pending.objects[0].item;
 720         flags1 = o1->flags;
 721         o2 = rev->pending.objects[1].item;
 722         flags2 = o2->flags;
 723
 724         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
 725                 die(_("Not a range."));
 726
 727         init_patch_ids(ids);
 728
 729         /* given a range a..b get all patch ids for b..a */
 730         init_revisions(&check_rev, rev->prefix);
 731         check_rev.max_parents = 1;
 732         o1->flags ^= UNINTERESTING;
 733         o2->flags ^= UNINTERESTING;
 734         add_pending_object(&check_rev, o1, "o1");
 735         add_pending_object(&check_rev, o2, "o2");
 736         if (prepare_revision_walk(&check_rev))
 737                 die(_("revision walk setup failed"));
 738
 739         while ((commit = get_revision(&check_rev)) != NULL) {
 740                 add_commit_patch_id(commit, ids);
 741         }
 742
 743         /* reset for next revision walk */
 744         clear_commit_marks((struct commit *)o1,
 745                         SEEN | UNINTERESTING | SHOWN | ADDED);
 746         clear_commit_marks((struct commit *)o2,
 747                         SEEN | UNINTERESTING | SHOWN | ADDED);
 748         o1->flags = flags1;
 749         o2->flags = flags2;
 750 }
 751
 752 static void gen_message_id(struct rev_info *info, char *base)
 753 {
 754         struct strbuf buf = STRBUF_INIT;
 755         strbuf_addf(&buf, "%s.%lu.git.%s", base,
 756                     (unsigned long) time(NULL),
 757                     git_committer_info(IDENT_NO_NAME|IDENT_NO_DATE|IDENT_STRICT));
 758         info->message_id = strbuf_detach(&buf, NULL);
 759 }
 760
 761 static void print_signature(void)
 762 {
 763         if (signature && *signature)
 764                 printf("-- \n%s\n\n", signature);
 765 }
 766
 767 static void add_branch_description(struct strbuf *buf, const char *branch_name)
 768 {
 769         struct strbuf desc = STRBUF_INIT;
 770         if (!branch_name || !*branch_name)
 771                 return;
 772         read_branch_desc(&desc, branch_name);
 773         if (desc.len) {
 774                 strbuf_addch(buf, '\n');
 775                 strbuf_add(buf, desc.buf, desc.len);
 776                 strbuf_addch(buf, '\n');
 777         }
 778 }
 779
 780 static void make_cover_letter(struct rev_info *rev, int use_stdout,
 781                               struct commit *origin,
 782                               int nr, struct commit **list, struct commit *head,
 783                               const char *branch_name,
 784                               int quiet)
 785 {
 786         const char *committer;
 787         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
 788         const char *msg;
 789         struct shortlog log;
 790         struct strbuf sb = STRBUF_INIT;
 791         int i;
 792         const char *encoding = "UTF-8";
 793         struct diff_options opts;
 794         int need_8bit_cte = 0;
 795         struct pretty_print_context pp = {0};
 796
 797         if (rev->commit_format != CMIT_FMT_EMAIL)
 798                 die(_("Cover letter needs email format"));
 799
 800         committer = git_committer_info(0);
 801
 802         if (!use_stdout &&
 803             reopen_stdout(NULL, rev->numbered_files ? NULL : "cover-letter", rev, quiet))
 804                 return;
 805
 806         log_write_email_headers(rev, head, &pp.subject, &pp.after_subject,
 807                                 &need_8bit_cte);
 808
 809         for (i = 0; !need_8bit_cte && i < nr; i++)
 810                 if (has_non_ascii(list[i]->buffer))
 811                         need_8bit_cte = 1;
 812
 813         msg = body;
 814         pp.fmt = CMIT_FMT_EMAIL;
 815         pp.date_mode = DATE_RFC2822;
 816         pp_user_info(&pp, NULL, &sb, committer, encoding);
 817         pp_title_line(&pp, &msg, &sb, encoding, need_8bit_cte);
 818         pp_remainder(&pp, &msg, &sb, 0);
 819         add_branch_description(&sb, branch_name);
 820         printf("%s\n", sb.buf);
 821
 822         strbuf_release(&sb);
 823
 824         shortlog_init(&log);
 825         log.wrap_lines = 1;
 826         log.wrap = 72;
 827         log.in1 = 2;
 828         log.in2 = 4;
 829         for (i = 0; i < nr; i++)
 830                 shortlog_add_commit(&log, list[i]);
 831
 832         shortlog_output(&log);
 833
 834         /*
 835          * We can only do diffstat with a unique reference point
 836          */
 837         if (!origin)
 838                 return;
 839
 840         memcpy(&opts, &rev->diffopt, sizeof(opts));
 841         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
 842
 843         diff_setup_done(&opts);
 844
 845         diff_tree_sha1(origin->tree->object.sha1,
 846                        head->tree->object.sha1,
 847                        "", &opts);
 848         diffcore_std(&opts);
 849         diff_flush(&opts);
 850
 851         printf("\n");
 852         print_signature();
 853 }
 854
 855 static const char *clean_message_id(const char *msg_id)
 856 {
 857         char ch;
 858         const char *a, *z, *m;
 859
 860         m = msg_id;
 861         while ((ch = *m) && (isspace(ch) || (ch == '<')))
 862                 m++;
 863         a = m;
 864         z = NULL;
 865         while ((ch = *m)) {
 866                 if (!isspace(ch) && (ch != '>'))
 867                         z = m;
 868                 m++;
 869         }
 870         if (!z)
 871                 die(_("insane in-reply-to: %s"), msg_id);
 872         if (++z == m)
 873                 return a;
 874         return xmemdupz(a, z - a);
 875 }
 876
 877 static const char *set_outdir(const char *prefix, const char *output_directory)
 878 {
 879         if (output_directory && is_absolute_path(output_directory))
 880                 return output_directory;
 881
 882         if (!prefix || !*prefix) {
 883                 if (output_directory)
 884                         return output_directory;
 885                 /* The user did not explicitly ask for "./" */
 886                 outdir_offset = 2;
 887                 return "./";
 888         }
 889
 890         outdir_offset = strlen(prefix);
 891         if (!output_directory)
 892                 return prefix;
 893
 894         return xstrdup(prefix_filename(prefix, outdir_offset,
 895                                        output_directory));
 896 }
 897
 898 static const char * const builtin_format_patch_usage[] = {
 899         N_("git format-patch [options] [<since> | <revision range>]"),
 900         NULL
 901 };
 902
 903 static int keep_subject = 0;
 904
 905 static int keep_callback(const struct option *opt, const char *arg, int unset)
 906 {
 907         ((struct rev_info *)opt->value)->total = -1;
 908         keep_subject = 1;
 909         return 0;
 910 }
 911
 912 static int subject_prefix = 0;
 913
 914 static int subject_prefix_callback(const struct option *opt, const char *arg,
 915                             int unset)
 916 {
 917         subject_prefix = 1;
 918         ((struct rev_info *)opt->value)->subject_prefix = arg;
 919         return 0;
 920 }
 921
 922 static int numbered_cmdline_opt = 0;
 923
 924 static int numbered_callback(const struct option *opt, const char *arg,
 925                              int unset)
 926 {
 927         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
 928         if (unset)
 929                 auto_number =  0;
 930         return 0;
 931 }
 932
 933 static int no_numbered_callback(const struct option *opt, const char *arg,
 934                                 int unset)
 935 {
 936         return numbered_callback(opt, arg, 1);
 937 }
 938
 939 static int output_directory_callback(const struct option *opt, const char *arg,
 940                               int unset)
 941 {
 942         const char **dir = (const char **)opt->value;
 943         if (*dir)
 944                 die(_("Two output directories?"));
 945         *dir = arg;
 946         return 0;
 947 }
 948
 949 static int thread_callback(const struct option *opt, const char *arg, int unset)
 950 {
 951         int *thread = (int *)opt->value;
 952         if (unset)
 953                 *thread = 0;
 954         else if (!arg || !strcmp(arg, "shallow"))
 955                 *thread = THREAD_SHALLOW;
 956         else if (!strcmp(arg, "deep"))
 957                 *thread = THREAD_DEEP;
 958         else
 959                 return 1;
 960         return 0;
 961 }
 962
 963 static int attach_callback(const struct option *opt, const char *arg, int unset)
 964 {
 965         struct rev_info *rev = (struct rev_info *)opt->value;
 966         if (unset)
 967                 rev->mime_boundary = NULL;
 968         else if (arg)
 969                 rev->mime_boundary = arg;
 970         else
 971                 rev->mime_boundary = git_version_string;
 972         rev->no_inline = unset ? 0 : 1;
 973         return 0;
 974 }
 975
 976 static int inline_callback(const struct option *opt, const char *arg, int unset)
 977 {
 978         struct rev_info *rev = (struct rev_info *)opt->value;
 979         if (unset)
 980                 rev->mime_boundary = NULL;
 981         else if (arg)
 982                 rev->mime_boundary = arg;
 983         else
 984                 rev->mime_boundary = git_version_string;
 985         rev->no_inline = 0;
 986         return 0;
 987 }
 988
 989 static int header_callback(const struct option *opt, const char *arg, int unset)
 990 {
 991         if (unset) {
 992                 string_list_clear(&extra_hdr, 0);
 993                 string_list_clear(&extra_to, 0);
 994                 string_list_clear(&extra_cc, 0);
 995         } else {
 996             add_header(arg);
 997         }
 998         return 0;
 999 }
1000
1001 static int to_callback(const struct option *opt, const char *arg, int unset)
1002 {
1003         if (unset)
1004                 string_list_clear(&extra_to, 0);
1005         else
1006                 string_list_append(&extra_to, arg);
1007         return 0;
1008 }
1009
1010 static int cc_callback(const struct option *opt, const char *arg, int unset)
1011 {
1012         if (unset)
1013                 string_list_clear(&extra_cc, 0);
1014         else
1015                 string_list_append(&extra_cc, arg);
1016         return 0;
1017 }
1018
1019 static char *find_branch_name(struct rev_info *rev)
1020 {
1021         int i, positive = -1;
1022         unsigned char branch_sha1[20];
1023         const unsigned char *tip_sha1;
1024         const char *ref;
1025         char *full_ref, *branch = NULL;
1026
1027         for (i = 0; i < rev->cmdline.nr; i++) {
1028                 if (rev->cmdline.rev[i].flags & UNINTERESTING)
1029                         continue;
1030                 if (positive < 0)
1031                         positive = i;
1032                 else
1033                         return NULL;
1034         }
1035         if (0 <= positive) {
1036                 ref = rev->cmdline.rev[positive].name;
1037                 tip_sha1 = rev->cmdline.rev[positive].item->sha1;
1038         } else if (!rev->cmdline.nr && rev->pending.nr == 1 &&
1039                    !strcmp(rev->pending.objects[0].name, "HEAD")) {
1040                 /*
1041                  * No actual ref from command line, but "HEAD" from
1042                  * rev->def was added in setup_revisions()
1043                  * e.g. format-patch --cover-letter -12
1044                  */
1045                 ref = "HEAD";
1046                 tip_sha1 = rev->pending.objects[0].item->sha1;
1047         } else {
1048                 return NULL;
1049         }
1050         if (dwim_ref(ref, strlen(ref), branch_sha1, &full_ref) &&
1051             !prefixcmp(full_ref, "refs/heads/") &&
1052             !hashcmp(tip_sha1, branch_sha1))
1053                 branch = xstrdup(full_ref + strlen("refs/heads/"));
1054         free(full_ref);
1055         return branch;
1056 }
1057
1058 int cmd_format_patch(int argc, const char **argv, const char *prefix)
1059 {
1060         struct commit *commit;
1061         struct commit **list = NULL;
1062         struct rev_info rev;
1063         struct setup_revision_opt s_r_opt;
1064         int nr = 0, total, i;
1065         int use_stdout = 0;
1066         int start_number = -1;
1067         int just_numbers = 0;
1068         int ignore_if_in_upstream = 0;
1069         int cover_letter = 0;
1070         int boundary_count = 0;
1071         int no_binary_diff = 0;
1072         struct commit *origin = NULL, *head = NULL;
1073         const char *in_reply_to = NULL;
1074         struct patch_ids ids;
1075         char *add_signoff = NULL;
1076         struct strbuf buf = STRBUF_INIT;
1077         int use_patch_format = 0;
1078         int quiet = 0;
1079         int reroll_count = -1;
1080         char *branch_name = NULL;
1081         const struct option builtin_format_patch_options[] = {
1082                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
1083                             N_("use [PATCH n/m] even with a single patch"),
1084                             PARSE_OPT_NOARG, numbered_callback },
1085                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
1086                             N_("use [PATCH] even with multiple patches"),
1087                             PARSE_OPT_NOARG, no_numbered_callback },
1088                 OPT_BOOLEAN('s', "signoff", &do_signoff, N_("add Signed-off-by:")),
1089                 OPT_BOOLEAN(0, "stdout", &use_stdout,
1090                             N_("print patches to standard out")),
1091                 OPT_BOOLEAN(0, "cover-letter", &cover_letter,
1092                             N_("generate a cover letter")),
1093                 OPT_BOOLEAN(0, "numbered-files", &just_numbers,
1094                             N_("use simple number sequence for output file names")),
1095                 OPT_STRING(0, "suffix", &fmt_patch_suffix, N_("sfx"),
1096                             N_("use <sfx> instead of '.patch'")),
1097                 OPT_INTEGER(0, "start-number", &start_number,
1098                             N_("start numbering patches at <n> instead of 1")),
1099                 OPT_INTEGER('v', "reroll-count", &reroll_count,
1100                             N_("mark the series as Nth re-roll")),
1101                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, N_("prefix"),
1102                             N_("Use [<prefix>] instead of [PATCH]"),
1103                             PARSE_OPT_NONEG, subject_prefix_callback },
1104                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
1105                             N_("dir"), N_("store resulting files in <dir>"),
1106                             PARSE_OPT_NONEG, output_directory_callback },
1107                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
1108                             N_("don't strip/add [PATCH]"),
1109                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
1110                 OPT_BOOLEAN(0, "no-binary", &no_binary_diff,
1111                             N_("don't output binary diffs")),
1112                 OPT_BOOLEAN(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
1113                             N_("don't include a patch matching a commit upstream")),
1114                 { OPTION_BOOLEAN, 'p', "no-stat", &use_patch_format, NULL,
1115                   N_("show patch format instead of default (patch + stat)"),
1116                   PARSE_OPT_NONEG | PARSE_OPT_NOARG },
1117                 OPT_GROUP(N_("Messaging")),
1118                 { OPTION_CALLBACK, 0, "add-header", NULL, N_("header"),
1119                             N_("add email header"), 0, header_callback },
1120                 { OPTION_CALLBACK, 0, "to", NULL, N_("email"), N_("add To: header"),
1121                             0, to_callback },
1122                 { OPTION_CALLBACK, 0, "cc", NULL, N_("email"), N_("add Cc: header"),
1123                             0, cc_callback },
1124                 OPT_STRING(0, "in-reply-to", &in_reply_to, N_("message-id"),
1125                             N_("make first mail a reply to <message-id>")),
1126                 { OPTION_CALLBACK, 0, "attach", &rev, N_("boundary"),
1127                             N_("attach the patch"), PARSE_OPT_OPTARG,
1128                             attach_callback },
1129                 { OPTION_CALLBACK, 0, "inline", &rev, N_("boundary"),
1130                             N_("inline the patch"),
1131                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
1132                             inline_callback },
1133                 { OPTION_CALLBACK, 0, "thread", &thread, N_("style"),
1134                             N_("enable message threading, styles: shallow, deep"),
1135                             PARSE_OPT_OPTARG, thread_callback },
1136                 OPT_STRING(0, "signature", &signature, N_("signature"),
1137                             N_("add a signature")),
1138                 OPT_BOOLEAN(0, "quiet", &quiet,
1139                             N_("don't print the patch filenames")),
1140                 OPT_END()
1141         };
1142
1143         extra_hdr.strdup_strings = 1;
1144         extra_to.strdup_strings = 1;
1145         extra_cc.strdup_strings = 1;
1146         init_grep_defaults();
1147         git_config(git_format_config, NULL);
1148         init_revisions(&rev, prefix);
1149         rev.commit_format = CMIT_FMT_EMAIL;
1150         rev.verbose_header = 1;
1151         rev.diff = 1;
1152         rev.max_parents = 1;
1153         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
1154         rev.subject_prefix = fmt_patch_subject_prefix;
1155         memset(&s_r_opt, 0, sizeof(s_r_opt));
1156         s_r_opt.def = "HEAD";
1157         s_r_opt.revarg_opt = REVARG_COMMITTISH;
1158
1159         if (default_attach) {
1160                 rev.mime_boundary = default_attach;
1161                 rev.no_inline = 1;
1162         }
1163
1164         /*
1165          * Parse the arguments before setup_revisions(), or something
1166          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1167          * possibly a valid SHA1.
1168          */
1169         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1170                              builtin_format_patch_usage,
1171                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1172                              PARSE_OPT_KEEP_DASHDASH);
1173
1174         if (0 < reroll_count) {
1175                 struct strbuf sprefix = STRBUF_INIT;
1176                 strbuf_addf(&sprefix, "%s v%d",
1177                             rev.subject_prefix, reroll_count);
1178                 rev.reroll_count = reroll_count;
1179                 rev.subject_prefix = strbuf_detach(&sprefix, NULL);
1180         }
1181
1182         if (do_signoff) {
1183                 const char *committer;
1184                 const char *endpos;
1185                 committer = git_committer_info(IDENT_STRICT);
1186                 endpos = strchr(committer, '>');
1187                 if (!endpos)
1188                         die(_("bogus committer info %s"), committer);
1189                 add_signoff = xmemdupz(committer, endpos - committer + 1);
1190         }
1191
1192         for (i = 0; i < extra_hdr.nr; i++) {
1193                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1194                 strbuf_addch(&buf, '\n');
1195         }
1196
1197         if (extra_to.nr)
1198                 strbuf_addstr(&buf, "To: ");
1199         for (i = 0; i < extra_to.nr; i++) {
1200                 if (i)
1201                         strbuf_addstr(&buf, "    ");
1202                 strbuf_addstr(&buf, extra_to.items[i].string);
1203                 if (i + 1 < extra_to.nr)
1204                         strbuf_addch(&buf, ',');
1205                 strbuf_addch(&buf, '\n');
1206         }
1207
1208         if (extra_cc.nr)
1209                 strbuf_addstr(&buf, "Cc: ");
1210         for (i = 0; i < extra_cc.nr; i++) {
1211                 if (i)
1212                         strbuf_addstr(&buf, "    ");
1213                 strbuf_addstr(&buf, extra_cc.items[i].string);
1214                 if (i + 1 < extra_cc.nr)
1215                         strbuf_addch(&buf, ',');
1216                 strbuf_addch(&buf, '\n');
1217         }
1218
1219         rev.extra_headers = strbuf_detach(&buf, NULL);
1220
1221         if (start_number < 0)
1222                 start_number = 1;
1223
1224         /*
1225          * If numbered is set solely due to format.numbered in config,
1226          * and it would conflict with --keep-subject (-k) from the
1227          * command line, reset "numbered".
1228          */
1229         if (numbered && keep_subject && !numbered_cmdline_opt)
1230                 numbered = 0;
1231
1232         if (numbered && keep_subject)
1233                 die (_("-n and -k are mutually exclusive."));
1234         if (keep_subject && subject_prefix)
1235                 die (_("--subject-prefix and -k are mutually exclusive."));
1236         rev.preserve_subject = keep_subject;
1237
1238         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1239         if (argc > 1)
1240                 die (_("unrecognized argument: %s"), argv[1]);
1241
1242         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1243                 die(_("--name-only does not make sense"));
1244         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1245                 die(_("--name-status does not make sense"));
1246         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1247                 die(_("--check does not make sense"));
1248
1249         if (!use_patch_format &&
1250                 (!rev.diffopt.output_format ||
1251                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1252                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1253
1254         /* Always generate a patch */
1255         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1256
1257         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1258                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1259
1260         if (rev.show_notes)
1261                 init_display_notes(&rev.notes_opt);
1262
1263         if (!use_stdout)
1264                 output_directory = set_outdir(prefix, output_directory);
1265         else
1266                 setup_pager();
1267
1268         if (output_directory) {
1269                 if (use_stdout)
1270                         die(_("standard output, or directory, which one?"));
1271                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1272                         die_errno(_("Could not create directory '%s'"),
1273                                   output_directory);
1274         }
1275
1276         if (rev.pending.nr == 1) {
1277                 if (rev.max_count < 0 && !rev.show_root_diff) {
1278                         /*
1279                          * This is traditional behaviour of "git format-patch
1280                          * origin" that prepares what the origin side still
1281                          * does not have.
1282                          */
1283                         unsigned char sha1[20];
1284                         const char *ref;
1285
1286                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1287                         add_head_to_pending(&rev);
1288                         ref = resolve_ref_unsafe("HEAD", sha1, 1, NULL);
1289                         if (ref && !prefixcmp(ref, "refs/heads/"))
1290                                 branch_name = xstrdup(ref + strlen("refs/heads/"));
1291                         else
1292                                 branch_name = xstrdup(""); /* no branch */
1293                 }
1294                 /*
1295                  * Otherwise, it is "format-patch -22 HEAD", and/or
1296                  * "format-patch --root HEAD".  The user wants
1297                  * get_revision() to do the usual traversal.
1298                  */
1299         }
1300
1301         /*
1302          * We cannot move this anywhere earlier because we do want to
1303          * know if --root was given explicitly from the command line.
1304          */
1305         rev.show_root_diff = 1;
1306
1307         if (cover_letter) {
1308                 /*
1309                  * NEEDSWORK:randomly pick one positive commit to show
1310                  * diffstat; this is often the tip and the command
1311                  * happens to do the right thing in most cases, but a
1312                  * complex command like "--cover-letter a b c ^bottom"
1313                  * picks "c" and shows diffstat between bottom..c
1314                  * which may not match what the series represents at
1315                  * all and totally broken.
1316                  */
1317                 int i;
1318                 for (i = 0; i < rev.pending.nr; i++) {
1319                         struct object *o = rev.pending.objects[i].item;
1320                         if (!(o->flags & UNINTERESTING))
1321                                 head = (struct commit *)o;
1322                 }
1323                 /* There is nothing to show; it is not an error, though. */
1324                 if (!head)
1325                         return 0;
1326                 if (!branch_name)
1327                         branch_name = find_branch_name(&rev);
1328         }
1329
1330         if (ignore_if_in_upstream) {
1331                 /* Don't say anything if head and upstream are the same. */
1332                 if (rev.pending.nr == 2) {
1333                         struct object_array_entry *o = rev.pending.objects;
1334                         if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1335                                 return 0;
1336                 }
1337                 get_patch_ids(&rev, &ids);
1338         }
1339
1340         if (!use_stdout)
1341                 realstdout = xfdopen(xdup(1), "w");
1342
1343         if (prepare_revision_walk(&rev))
1344                 die(_("revision walk setup failed"));
1345         rev.boundary = 1;
1346         while ((commit = get_revision(&rev)) != NULL) {
1347                 if (commit->object.flags & BOUNDARY) {
1348                         boundary_count++;
1349                         origin = (boundary_count == 1) ? commit : NULL;
1350                         continue;
1351                 }
1352
1353                 if (ignore_if_in_upstream &&
1354                                 has_commit_patch_id(commit, &ids))
1355                         continue;
1356
1357                 nr++;
1358                 list = xrealloc(list, nr * sizeof(list[0]));
1359                 list[nr - 1] = commit;
1360         }
1361         total = nr;
1362         if (!keep_subject && auto_number && total > 1)
1363                 numbered = 1;
1364         if (numbered)
1365                 rev.total = total + start_number - 1;
1366         if (in_reply_to || thread || cover_letter)
1367                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1368         if (in_reply_to) {
1369                 const char *msgid = clean_message_id(in_reply_to);
1370                 string_list_append(rev.ref_message_ids, msgid);
1371         }
1372         rev.numbered_files = just_numbers;
1373         rev.patch_suffix = fmt_patch_suffix;
1374         if (cover_letter) {
1375                 if (thread)
1376                         gen_message_id(&rev, "cover");
1377                 make_cover_letter(&rev, use_stdout,
1378                                   origin, nr, list, head, branch_name, quiet);
1379                 total++;
1380                 start_number--;
1381         }
1382         rev.add_signoff = add_signoff;
1383         while (0 <= --nr) {
1384                 int shown;
1385                 commit = list[nr];
1386                 rev.nr = total - nr + (start_number - 1);
1387                 /* Make the second and subsequent mails replies to the first */
1388                 if (thread) {
1389                         /* Have we already had a message ID? */
1390                         if (rev.message_id) {
1391                                 /*
1392                                  * For deep threading: make every mail
1393                                  * a reply to the previous one, no
1394                                  * matter what other options are set.
1395                                  *
1396                                  * For shallow threading:
1397                                  *
1398                                  * Without --cover-letter and
1399                                  * --in-reply-to, make every mail a
1400                                  * reply to the one before.
1401                                  *
1402                                  * With --in-reply-to but no
1403                                  * --cover-letter, make every mail a
1404                                  * reply to the <reply-to>.
1405                                  *
1406                                  * With --cover-letter, make every
1407                                  * mail but the cover letter a reply
1408                                  * to the cover letter.  The cover
1409                                  * letter is a reply to the
1410                                  * --in-reply-to, if specified.
1411                                  */
1412                                 if (thread == THREAD_SHALLOW
1413                                     && rev.ref_message_ids->nr > 0
1414                                     && (!cover_letter || rev.nr > 1))
1415                                         free(rev.message_id);
1416                                 else
1417                                         string_list_append(rev.ref_message_ids,
1418                                                            rev.message_id);
1419                         }
1420                         gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
1421                 }
1422
1423                 if (!use_stdout &&
1424                     reopen_stdout(rev.numbered_files ? NULL : commit, NULL, &rev, quiet))
1425                         die(_("Failed to create output files"));
1426                 shown = log_tree_commit(&rev, commit);
1427                 free(commit->buffer);
1428                 commit->buffer = NULL;
1429
1430                 /* We put one extra blank line between formatted
1431                  * patches and this flag is used by log-tree code
1432                  * to see if it needs to emit a LF before showing
1433                  * the log; when using one file per patch, we do
1434                  * not want the extra blank line.
1435                  */
1436                 if (!use_stdout)
1437                         rev.shown_one = 0;
1438                 if (shown) {
1439                         if (rev.mime_boundary)
1440                                 printf("\n--%s%s--\n\n\n",
1441                                        mime_boundary_leader,
1442                                        rev.mime_boundary);
1443                         else
1444                                 print_signature();
1445                 }
1446                 if (!use_stdout)
1447                         fclose(stdout);
1448         }
1449         free(list);
1450         free(branch_name);
1451         string_list_clear(&extra_to, 0);
1452         string_list_clear(&extra_cc, 0);
1453         string_list_clear(&extra_hdr, 0);
1454         if (ignore_if_in_upstream)
1455                 free_patch_ids(&ids);
1456         return 0;
1457 }
1458
1459 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1460 {
1461         unsigned char sha1[20];
1462         if (get_sha1(arg, sha1) == 0) {
1463                 struct commit *commit = lookup_commit_reference(sha1);
1464                 if (commit) {
1465                         commit->object.flags |= flags;
1466                         add_pending_object(revs, &commit->object, arg);
1467                         return 0;
1468                 }
1469         }
1470         return -1;
1471 }
1472
1473 static const char * const cherry_usage[] = {
1474         N_("git cherry [-v] [<upstream> [<head> [<limit>]]]"),
1475         NULL
1476 };
1477
1478 static void print_commit(char sign, struct commit *commit, int verbose,
1479                          int abbrev)
1480 {
1481         if (!verbose) {
1482                 printf("%c %s\n", sign,
1483                        find_unique_abbrev(commit->object.sha1, abbrev));
1484         } else {
1485                 struct strbuf buf = STRBUF_INIT;
1486                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
1487                 printf("%c %s %s\n", sign,
1488                        find_unique_abbrev(commit->object.sha1, abbrev),
1489                        buf.buf);
1490                 strbuf_release(&buf);
1491         }
1492 }
1493
1494 int cmd_cherry(int argc, const char **argv, const char *prefix)
1495 {
1496         struct rev_info revs;
1497         struct patch_ids ids;
1498         struct commit *commit;
1499         struct commit_list *list = NULL;
1500         struct branch *current_branch;
1501         const char *upstream;
1502         const char *head = "HEAD";
1503         const char *limit = NULL;
1504         int verbose = 0, abbrev = 0;
1505
1506         struct option options[] = {
1507                 OPT__ABBREV(&abbrev),
1508                 OPT__VERBOSE(&verbose, N_("be verbose")),
1509                 OPT_END()
1510         };
1511
1512         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
1513
1514         switch (argc) {
1515         case 3:
1516                 limit = argv[2];
1517                 /* FALLTHROUGH */
1518         case 2:
1519                 head = argv[1];
1520                 /* FALLTHROUGH */
1521         case 1:
1522                 upstream = argv[0];
1523                 break;
1524         default:
1525                 current_branch = branch_get(NULL);
1526                 if (!current_branch || !current_branch->merge
1527                                         || !current_branch->merge[0]
1528                                         || !current_branch->merge[0]->dst) {
1529                         fprintf(stderr, _("Could not find a tracked"
1530                                         " remote branch, please"
1531                                         " specify <upstream> manually.\n"));
1532                         usage_with_options(cherry_usage, options);
1533                 }
1534
1535                 upstream = current_branch->merge[0]->dst;
1536         }
1537
1538         init_revisions(&revs, prefix);
1539         revs.max_parents = 1;
1540
1541         if (add_pending_commit(head, &revs, 0))
1542                 die(_("Unknown commit %s"), head);
1543         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1544                 die(_("Unknown commit %s"), upstream);
1545
1546         /* Don't say anything if head and upstream are the same. */
1547         if (revs.pending.nr == 2) {
1548                 struct object_array_entry *o = revs.pending.objects;
1549                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1550                         return 0;
1551         }
1552
1553         get_patch_ids(&revs, &ids);
1554
1555         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1556                 die(_("Unknown commit %s"), limit);
1557
1558         /* reverse the list of commits */
1559         if (prepare_revision_walk(&revs))
1560                 die(_("revision walk setup failed"));
1561         while ((commit = get_revision(&revs)) != NULL) {
1562                 commit_list_insert(commit, &list);
1563         }
1564
1565         while (list) {
1566                 char sign = '+';
1567
1568                 commit = list->item;
1569                 if (has_commit_patch_id(commit, &ids))
1570                         sign = '-';
1571                 print_commit(sign, commit, verbose, abbrev);
1572                 list = list->next;
1573         }
1574
1575         free_patch_ids(&ids);
1576         return 0;
1577 }