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 #include "mailmap.h"
  26
  27 /* Set a default date-time format for git log ("log.date" config variable) */
  28 static const char *default_date_mode = NULL;
  29
  30 static int default_abbrev_commit;
  31 static int default_show_root = 1;
  32 static int decoration_style;
  33 static int decoration_given;
  34 static int use_mailmap_config;
  35 static const char *fmt_patch_subject_prefix = "PATCH";
  36 static const char *fmt_pretty;
  37
  38 static const char * const builtin_log_usage[] = {
  39         N_("git log [<options>] [<since>..<until>] [[--] <path>...]\n")
  40         N_("   or: git show [options] <object>..."),
  41         NULL
  42 };
  43
  44 static int parse_decoration_style(const char *var, const char *value)
  45 {
  46         switch (git_config_maybe_bool(var, value)) {
  47         case 1:
  48                 return DECORATE_SHORT_REFS;
  49         case 0:
  50                 return 0;
  51         default:
  52                 break;
  53         }
  54         if (!strcmp(value, "full"))
  55                 return DECORATE_FULL_REFS;
  56         else if (!strcmp(value, "short"))
  57                 return DECORATE_SHORT_REFS;
  58         return -1;
  59 }
  60
  61 static int decorate_callback(const struct option *opt, const char *arg, int unset)
  62 {
  63         if (unset)
  64                 decoration_style = 0;
  65         else if (arg)
  66                 decoration_style = parse_decoration_style("command line", arg);
  67         else
  68                 decoration_style = DECORATE_SHORT_REFS;
  69
  70         if (decoration_style < 0)
  71                 die("invalid --decorate option: %s", arg);
  72
  73         decoration_given = 1;
  74
  75         return 0;
  76 }
  77
  78 static void cmd_log_init_defaults(struct rev_info *rev)
  79 {
  80         if (fmt_pretty)
  81                 get_commit_format(fmt_pretty, rev);
  82         rev->verbose_header = 1;
  83         DIFF_OPT_SET(&rev->diffopt, RECURSIVE);
  84         rev->diffopt.stat_width = -1; /* use full terminal width */
  85         rev->diffopt.stat_graph_width = -1; /* respect statGraphWidth config */
  86         rev->abbrev_commit = default_abbrev_commit;
  87         rev->show_root_diff = default_show_root;
  88         rev->subject_prefix = fmt_patch_subject_prefix;
  89         DIFF_OPT_SET(&rev->diffopt, ALLOW_TEXTCONV);
  90
  91         if (default_date_mode)
  92                 rev->date_mode = parse_date_format(default_date_mode);
  93 }
  94
  95 static void cmd_log_init_finish(int argc, const char **argv, const char *prefix,
  96                          struct rev_info *rev, struct setup_revision_opt *opt)
  97 {
  98         struct userformat_want w;
  99         int quiet = 0, source = 0, mailmap = 0;
 100
 101         const struct option builtin_log_options[] = {
 102                 OPT_BOOLEAN(0, "quiet", &quiet, N_("suppress diff output")),
 103                 OPT_BOOLEAN(0, "source", &source, N_("show source")),
 104                 OPT_BOOLEAN(0, "use-mailmap", &mailmap, N_("Use mail map file")),
 105                 { OPTION_CALLBACK, 0, "decorate", NULL, NULL, N_("decorate options"),
 106                   PARSE_OPT_OPTARG, decorate_callback},
 107                 OPT_END()
 108         };
 109
 110         mailmap = use_mailmap_config;
 111         argc = parse_options(argc, argv, prefix,
 112                              builtin_log_options, builtin_log_usage,
 113                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
 114                              PARSE_OPT_KEEP_DASHDASH);
 115
 116         if (quiet)
 117                 rev->diffopt.output_format |= DIFF_FORMAT_NO_OUTPUT;
 118         argc = setup_revisions(argc, argv, rev, opt);
 119
 120         /* Any arguments at this point are not recognized */
 121         if (argc > 1)
 122                 die("unrecognized argument: %s", argv[1]);
 123
 124         memset(&w, 0, sizeof(w));
 125         userformat_find_requirements(NULL, &w);
 126
 127         if (!rev->show_notes_given && (!rev->pretty_given || w.notes))
 128                 rev->show_notes = 1;
 129         if (rev->show_notes)
 130                 init_display_notes(&rev->notes_opt);
 131
 132         if (rev->diffopt.pickaxe || rev->diffopt.filter)
 133                 rev->always_show_header = 0;
 134         if (DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES)) {
 135                 rev->always_show_header = 0;
 136                 if (rev->diffopt.pathspec.nr != 1)
 137                         usage("git logs can only follow renames on one pathname at a time");
 138         }
 139
 140         if (source)
 141                 rev->show_source = 1;
 142
 143         if (mailmap) {
 144                 rev->mailmap = xcalloc(1, sizeof(struct string_list));
 145                 read_mailmap(rev->mailmap, NULL);
 146         }
 147
 148         if (rev->pretty_given && rev->commit_format == CMIT_FMT_RAW) {
 149                 /*
 150                  * "log --pretty=raw" is special; ignore UI oriented
 151                  * configuration variables such as decoration.
 152                  */
 153                 if (!decoration_given)
 154                         decoration_style = 0;
 155                 if (!rev->abbrev_commit_given)
 156                         rev->abbrev_commit = 0;
 157         }
 158
 159         if (decoration_style) {
 160                 rev->show_decorations = 1;
 161                 load_ref_decorations(decoration_style);
 162         }
 163         setup_pager();
 164 }
 165
 166 static void cmd_log_init(int argc, const char **argv, const char *prefix,
 167                          struct rev_info *rev, struct setup_revision_opt *opt)
 168 {
 169         cmd_log_init_defaults(rev);
 170         cmd_log_init_finish(argc, argv, prefix, rev, opt);
 171 }
 172
 173 /*
 174  * This gives a rough estimate for how many commits we
 175  * will print out in the list.
 176  */
 177 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
 178 {
 179         int n = 0;
 180
 181         while (list) {
 182                 struct commit *commit = list->item;
 183                 unsigned int flags = commit->object.flags;
 184                 list = list->next;
 185                 if (!(flags & (TREESAME | UNINTERESTING)))
 186                         n++;
 187         }
 188         return n;
 189 }
 190
 191 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
 192 {
 193         if (rev->shown_one) {
 194                 rev->shown_one = 0;
 195                 if (rev->commit_format != CMIT_FMT_ONELINE)
 196                         putchar(rev->diffopt.line_termination);
 197         }
 198         printf(_("Final output: %d %s\n"), nr, stage);
 199 }
 200
 201 static struct itimerval early_output_timer;
 202
 203 static void log_show_early(struct rev_info *revs, struct commit_list *list)
 204 {
 205         int i = revs->early_output;
 206         int show_header = 1;
 207
 208         sort_in_topological_order(&list, revs->lifo);
 209         while (list && i) {
 210                 struct commit *commit = list->item;
 211                 switch (simplify_commit(revs, commit)) {
 212                 case commit_show:
 213                         if (show_header) {
 214                                 int n = estimate_commit_count(revs, list);
 215                                 show_early_header(revs, "incomplete", n);
 216                                 show_header = 0;
 217                         }
 218                         log_tree_commit(revs, commit);
 219                         i--;
 220                         break;
 221                 case commit_ignore:
 222                         break;
 223                 case commit_error:
 224                         return;
 225                 }
 226                 list = list->next;
 227         }
 228
 229         /* Did we already get enough commits for the early output? */
 230         if (!i)
 231                 return;
 232
 233         /*
 234          * ..if no, then repeat it twice a second until we
 235          * do.
 236          *
 237          * NOTE! We don't use "it_interval", because if the
 238          * reader isn't listening, we want our output to be
 239          * throttled by the writing, and not have the timer
 240          * trigger every second even if we're blocked on a
 241          * reader!
 242          */
 243         early_output_timer.it_value.tv_sec = 0;
 244         early_output_timer.it_value.tv_usec = 500000;
 245         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 246 }
 247
 248 static void early_output(int signal)
 249 {
 250         show_early_output = log_show_early;
 251 }
 252
 253 static void setup_early_output(struct rev_info *rev)
 254 {
 255         struct sigaction sa;
 256
 257         /*
 258          * Set up the signal handler, minimally intrusively:
 259          * we only set a single volatile integer word (not
 260          * using sigatomic_t - trying to avoid unnecessary
 261          * system dependencies and headers), and using
 262          * SA_RESTART.
 263          */
 264         memset(&sa, 0, sizeof(sa));
 265         sa.sa_handler = early_output;
 266         sigemptyset(&sa.sa_mask);
 267         sa.sa_flags = SA_RESTART;
 268         sigaction(SIGALRM, &sa, NULL);
 269
 270         /*
 271          * If we can get the whole output in less than a
 272          * tenth of a second, don't even bother doing the
 273          * early-output thing..
 274          *
 275          * This is a one-time-only trigger.
 276          */
 277         early_output_timer.it_value.tv_sec = 0;
 278         early_output_timer.it_value.tv_usec = 100000;
 279         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 280 }
 281
 282 static void finish_early_output(struct rev_info *rev)
 283 {
 284         int n = estimate_commit_count(rev, rev->commits);
 285         signal(SIGALRM, SIG_IGN);
 286         show_early_header(rev, "done", n);
 287 }
 288
 289 static int cmd_log_walk(struct rev_info *rev)
 290 {
 291         struct commit *commit;
 292         int saved_nrl = 0;
 293         int saved_dcctc = 0;
 294
 295         if (rev->early_output)
 296                 setup_early_output(rev);
 297
 298         if (prepare_revision_walk(rev))
 299                 die(_("revision walk setup failed"));
 300
 301         if (rev->early_output)
 302                 finish_early_output(rev);
 303
 304         /*
 305          * For --check and --exit-code, the exit code is based on CHECK_FAILED
 306          * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
 307          * retain that state information if replacing rev->diffopt in this loop
 308          */
 309         while ((commit = get_revision(rev)) != NULL) {
 310                 if (!log_tree_commit(rev, commit) &&
 311                     rev->max_count >= 0)
 312                         /*
 313                          * We decremented max_count in get_revision,
 314                          * but we didn't actually show the commit.
 315                          */
 316                         rev->max_count++;
 317                 if (!rev->reflog_info) {
 318                         /* we allow cycles in reflog ancestry */
 319                         free(commit->buffer);
 320                         commit->buffer = NULL;
 321                 }
 322                 free_commit_list(commit->parents);
 323                 commit->parents = NULL;
 324                 if (saved_nrl < rev->diffopt.needed_rename_limit)
 325                         saved_nrl = rev->diffopt.needed_rename_limit;
 326                 if (rev->diffopt.degraded_cc_to_c)
 327                         saved_dcctc = 1;
 328         }
 329         rev->diffopt.degraded_cc_to_c = saved_dcctc;
 330         rev->diffopt.needed_rename_limit = saved_nrl;
 331
 332         if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
 333             DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
 334                 return 02;
 335         }
 336         return diff_result_code(&rev->diffopt, 0);
 337 }
 338
 339 static int git_log_config(const char *var, const char *value, void *cb)
 340 {
 341         if (!strcmp(var, "format.pretty"))
 342                 return git_config_string(&fmt_pretty, var, value);
 343         if (!strcmp(var, "format.subjectprefix"))
 344                 return git_config_string(&fmt_patch_subject_prefix, var, value);
 345         if (!strcmp(var, "log.abbrevcommit")) {
 346                 default_abbrev_commit = git_config_bool(var, value);
 347                 return 0;
 348         }
 349         if (!strcmp(var, "log.date"))
 350                 return git_config_string(&default_date_mode, var, value);
 351         if (!strcmp(var, "log.decorate")) {
 352                 decoration_style = parse_decoration_style(var, value);
 353                 if (decoration_style < 0)
 354                         decoration_style = 0; /* maybe warn? */
 355                 return 0;
 356         }
 357         if (!strcmp(var, "log.showroot")) {
 358                 default_show_root = git_config_bool(var, value);
 359                 return 0;
 360         }
 361         if (!prefixcmp(var, "color.decorate."))
 362                 return parse_decorate_color_config(var, 15, value);
 363         if (!strcmp(var, "log.mailmap")) {
 364                 use_mailmap_config = git_config_bool(var, value);
 365                 return 0;
 366         }
 367
 368         if (grep_config(var, value, cb) < 0)
 369                 return -1;
 370         return git_diff_ui_config(var, value, cb);
 371 }
 372
 373 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 374 {
 375         struct rev_info rev;
 376         struct setup_revision_opt opt;
 377
 378         init_grep_defaults();
 379         git_config(git_log_config, NULL);
 380
 381         init_revisions(&rev, prefix);
 382         rev.diff = 1;
 383         rev.simplify_history = 0;
 384         memset(&opt, 0, sizeof(opt));
 385         opt.def = "HEAD";
 386         opt.revarg_opt = REVARG_COMMITTISH;
 387         cmd_log_init(argc, argv, prefix, &rev, &opt);
 388         if (!rev.diffopt.output_format)
 389                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
 390         return cmd_log_walk(&rev);
 391 }
 392
 393 static void show_tagger(char *buf, int len, struct rev_info *rev)
 394 {
 395         struct strbuf out = STRBUF_INIT;
 396         struct pretty_print_context pp = {0};
 397
 398         pp.fmt = rev->commit_format;
 399         pp.date_mode = rev->date_mode;
 400         pp_user_info(&pp, "Tagger", &out, buf, get_log_output_encoding());
 401         printf("%s", out.buf);
 402         strbuf_release(&out);
 403 }
 404
 405 static int show_blob_object(const unsigned char *sha1, struct rev_info *rev)
 406 {
 407         fflush(stdout);
 408         return stream_blob_to_fd(1, sha1, NULL, 0);
 409 }
 410
 411 static int show_tag_object(const unsigned char *sha1, struct rev_info *rev)
 412 {
 413         unsigned long size;
 414         enum object_type type;
 415         char *buf = read_sha1_file(sha1, &type, &size);
 416         int offset = 0;
 417
 418         if (!buf)
 419                 return error(_("Could not read object %s"), sha1_to_hex(sha1));
 420
 421         assert(type == OBJ_TAG);
 422         while (offset < size && buf[offset] != '\n') {
 423                 int new_offset = offset + 1;
 424                 while (new_offset < size && buf[new_offset++] != '\n')
 425                         ; /* do nothing */
 426                 if (!prefixcmp(buf + offset, "tagger "))
 427                         show_tagger(buf + offset + 7,
 428                                     new_offset - offset - 7, rev);
 429                 offset = new_offset;
 430         }
 431
 432         if (offset < size)
 433                 fwrite(buf + offset, size - offset, 1, stdout);
 434         free(buf);
 435         return 0;
 436 }
 437
 438 static int show_tree_object(const unsigned char *sha1,
 439                 const char *base, int baselen,
 440                 const char *pathname, unsigned mode, int stage, void *context)
 441 {
 442         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
 443         return 0;
 444 }
 445
 446 static void show_rev_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
 447 {
 448         if (rev->ignore_merges) {
 449                 /* There was no "-m" on the command line */
 450                 rev->ignore_merges = 0;
 451                 if (!rev->first_parent_only && !rev->combine_merges) {
 452                         /* No "--first-parent", "-c", nor "--cc" */
 453                         rev->combine_merges = 1;
 454                         rev->dense_combined_merges = 1;
 455                 }
 456         }
 457         if (!rev->diffopt.output_format)
 458                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
 459 }
 460
 461 int cmd_show(int argc, const char **argv, const char *prefix)
 462 {
 463         struct rev_info rev;
 464         struct object_array_entry *objects;
 465         struct setup_revision_opt opt;
 466         struct pathspec match_all;
 467         int i, count, ret = 0;
 468
 469         init_grep_defaults();
 470         git_config(git_log_config, NULL);
 471
 472         init_pathspec(&match_all, NULL);
 473         init_revisions(&rev, prefix);
 474         rev.diff = 1;
 475         rev.always_show_header = 1;
 476         rev.no_walk = REVISION_WALK_NO_WALK_SORTED;
 477         rev.diffopt.stat_width = -1;    /* Scale to real terminal size */
 478
 479         memset(&opt, 0, sizeof(opt));
 480         opt.def = "HEAD";
 481         opt.tweak = show_rev_tweak_rev;
 482         cmd_log_init(argc, argv, prefix, &rev, &opt);
 483
 484         if (!rev.no_walk)
 485                 return cmd_log_walk(&rev);
 486
 487         count = rev.pending.nr;
 488         objects = rev.pending.objects;
 489         for (i = 0; i < count && !ret; i++) {
 490                 struct object *o = objects[i].item;
 491                 const char *name = objects[i].name;
 492                 switch (o->type) {
 493                 case OBJ_BLOB:
 494                         ret = show_blob_object(o->sha1, NULL);
 495                         break;
 496                 case OBJ_TAG: {
 497                         struct tag *t = (struct tag *)o;
 498
 499                         if (rev.shown_one)
 500                                 putchar('\n');
 501                         printf("%stag %s%s\n",
 502                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 503                                         t->tag,
 504                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 505                         ret = show_tag_object(o->sha1, &rev);
 506                         rev.shown_one = 1;
 507                         if (ret)
 508                                 break;
 509                         o = parse_object(t->tagged->sha1);
 510                         if (!o)
 511                                 ret = error(_("Could not read object %s"),
 512                                             sha1_to_hex(t->tagged->sha1));
 513                         objects[i].item = o;
 514                         i--;
 515                         break;
 516                 }
 517                 case OBJ_TREE:
 518                         if (rev.shown_one)
 519                                 putchar('\n');
 520                         printf("%stree %s%s\n\n",
 521                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 522                                         name,
 523                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 524                         read_tree_recursive((struct tree *)o, "", 0, 0, &match_all,
 525                                         show_tree_object, NULL);
 526                         rev.shown_one = 1;
 527                         break;
 528                 case OBJ_COMMIT:
 529                         rev.pending.nr = rev.pending.alloc = 0;
 530                         rev.pending.objects = NULL;
 531                         add_object_array(o, name, &rev.pending);
 532                         ret = cmd_log_walk(&rev);
 533                         break;
 534                 default:
 535                         ret = error(_("Unknown type: %d"), o->type);
 536                 }
 537         }
 538         free(objects);
 539         return ret;
 540 }
 541
 542 /*
 543  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
 544  */
 545 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
 546 {
 547         struct rev_info rev;
 548         struct setup_revision_opt opt;
 549
 550         init_grep_defaults();
 551         git_config(git_log_config, NULL);
 552
 553         init_revisions(&rev, prefix);
 554         init_reflog_walk(&rev.reflog_info);
 555         rev.verbose_header = 1;
 556         memset(&opt, 0, sizeof(opt));
 557         opt.def = "HEAD";
 558         cmd_log_init_defaults(&rev);
 559         rev.abbrev_commit = 1;
 560         rev.commit_format = CMIT_FMT_ONELINE;
 561         rev.use_terminator = 1;
 562         rev.always_show_header = 1;
 563         cmd_log_init_finish(argc, argv, prefix, &rev, &opt);
 564
 565         return cmd_log_walk(&rev);
 566 }
 567
 568 int cmd_log(int argc, const char **argv, const char *prefix)
 569 {
 570         struct rev_info rev;
 571         struct setup_revision_opt opt;
 572
 573         init_grep_defaults();
 574         git_config(git_log_config, NULL);
 575
 576         init_revisions(&rev, prefix);
 577         rev.always_show_header = 1;
 578         memset(&opt, 0, sizeof(opt));
 579         opt.def = "HEAD";
 580         opt.revarg_opt = REVARG_COMMITTISH;
 581         cmd_log_init(argc, argv, prefix, &rev, &opt);
 582         return cmd_log_walk(&rev);
 583 }
 584
 585 /* format-patch */
 586
 587 static const char *fmt_patch_suffix = ".patch";
 588 static int numbered = 0;
 589 static int auto_number = 1;
 590
 591 static char *default_attach = NULL;
 592
 593 static struct string_list extra_hdr;
 594 static struct string_list extra_to;
 595 static struct string_list extra_cc;
 596
 597 static void add_header(const char *value)
 598 {
 599         struct string_list_item *item;
 600         int len = strlen(value);
 601         while (len && value[len - 1] == '\n')
 602                 len--;
 603
 604         if (!strncasecmp(value, "to: ", 4)) {
 605                 item = string_list_append(&extra_to, value + 4);
 606                 len -= 4;
 607         } else if (!strncasecmp(value, "cc: ", 4)) {
 608                 item = string_list_append(&extra_cc, value + 4);
 609                 len -= 4;
 610         } else {
 611                 item = string_list_append(&extra_hdr, value);
 612         }
 613
 614         item->string[len] = '\0';
 615 }
 616
 617 #define THREAD_SHALLOW 1
 618 #define THREAD_DEEP 2
 619 static int thread;
 620 static int do_signoff;
 621 static const char *signature = git_version_string;
 622
 623 static int git_format_config(const char *var, const char *value, void *cb)
 624 {
 625         if (!strcmp(var, "format.headers")) {
 626                 if (!value)
 627                         die(_("format.headers without value"));
 628                 add_header(value);
 629                 return 0;
 630         }
 631         if (!strcmp(var, "format.suffix"))
 632                 return git_config_string(&fmt_patch_suffix, var, value);
 633         if (!strcmp(var, "format.to")) {
 634                 if (!value)
 635                         return config_error_nonbool(var);
 636                 string_list_append(&extra_to, value);
 637                 return 0;
 638         }
 639         if (!strcmp(var, "format.cc")) {
 640                 if (!value)
 641                         return config_error_nonbool(var);
 642                 string_list_append(&extra_cc, value);
 643                 return 0;
 644         }
 645         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff") ||
 646             !strcmp(var, "color.ui")) {
 647                 return 0;
 648         }
 649         if (!strcmp(var, "format.numbered")) {
 650                 if (value && !strcasecmp(value, "auto")) {
 651                         auto_number = 1;
 652                         return 0;
 653                 }
 654                 numbered = git_config_bool(var, value);
 655                 auto_number = auto_number && numbered;
 656                 return 0;
 657         }
 658         if (!strcmp(var, "format.attach")) {
 659                 if (value && *value)
 660                         default_attach = xstrdup(value);
 661                 else
 662                         default_attach = xstrdup(git_version_string);
 663                 return 0;
 664         }
 665         if (!strcmp(var, "format.thread")) {
 666                 if (value && !strcasecmp(value, "deep")) {
 667                         thread = THREAD_DEEP;
 668                         return 0;
 669                 }
 670                 if (value && !strcasecmp(value, "shallow")) {
 671                         thread = THREAD_SHALLOW;
 672                         return 0;
 673                 }
 674                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
 675                 return 0;
 676         }
 677         if (!strcmp(var, "format.signoff")) {
 678                 do_signoff = git_config_bool(var, value);
 679                 return 0;
 680         }
 681         if (!strcmp(var, "format.signature"))
 682                 return git_config_string(&signature, var, value);
 683
 684         return git_log_config(var, value, cb);
 685 }
 686
 687 static FILE *realstdout = NULL;
 688 static const char *output_directory = NULL;
 689 static int outdir_offset;
 690
 691 static int reopen_stdout(struct commit *commit, const char *subject,
 692                          struct rev_info *rev, int quiet)
 693 {
 694         struct strbuf filename = STRBUF_INIT;
 695         int suffix_len = strlen(rev->patch_suffix) + 1;
 696
 697         if (output_directory) {
 698                 strbuf_addstr(&filename, output_directory);
 699                 if (filename.len >=
 700                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
 701                         return error(_("name of output directory is too long"));
 702                 if (filename.buf[filename.len - 1] != '/')
 703                         strbuf_addch(&filename, '/');
 704         }
 705
 706         if (rev->numbered_files)
 707                 strbuf_addf(&filename, "%d", rev->nr);
 708         else if (commit)
 709                 fmt_output_commit(&filename, commit, rev);
 710         else
 711                 fmt_output_subject(&filename, subject, rev);
 712
 713         if (!quiet)
 714                 fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
 715
 716         if (freopen(filename.buf, "w", stdout) == NULL)
 717                 return error(_("Cannot open patch file %s"), filename.buf);
 718
 719         strbuf_release(&filename);
 720         return 0;
 721 }
 722
 723 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids)
 724 {
 725         struct rev_info check_rev;
 726         struct commit *commit;
 727         struct object *o1, *o2;
 728         unsigned flags1, flags2;
 729
 730         if (rev->pending.nr != 2)
 731                 die(_("Need exactly one range."));
 732
 733         o1 = rev->pending.objects[0].item;
 734         flags1 = o1->flags;
 735         o2 = rev->pending.objects[1].item;
 736         flags2 = o2->flags;
 737
 738         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
 739                 die(_("Not a range."));
 740
 741         init_patch_ids(ids);
 742
 743         /* given a range a..b get all patch ids for b..a */
 744         init_revisions(&check_rev, rev->prefix);
 745         check_rev.max_parents = 1;
 746         o1->flags ^= UNINTERESTING;
 747         o2->flags ^= UNINTERESTING;
 748         add_pending_object(&check_rev, o1, "o1");
 749         add_pending_object(&check_rev, o2, "o2");
 750         if (prepare_revision_walk(&check_rev))
 751                 die(_("revision walk setup failed"));
 752
 753         while ((commit = get_revision(&check_rev)) != NULL) {
 754                 add_commit_patch_id(commit, ids);
 755         }
 756
 757         /* reset for next revision walk */
 758         clear_commit_marks((struct commit *)o1,
 759                         SEEN | UNINTERESTING | SHOWN | ADDED);
 760         clear_commit_marks((struct commit *)o2,
 761                         SEEN | UNINTERESTING | SHOWN | ADDED);
 762         o1->flags = flags1;
 763         o2->flags = flags2;
 764 }
 765
 766 static void gen_message_id(struct rev_info *info, char *base)
 767 {
 768         struct strbuf buf = STRBUF_INIT;
 769         strbuf_addf(&buf, "%s.%lu.git.%s", base,
 770                     (unsigned long) time(NULL),
 771                     git_committer_info(IDENT_NO_NAME|IDENT_NO_DATE|IDENT_STRICT));
 772         info->message_id = strbuf_detach(&buf, NULL);
 773 }
 774
 775 static void print_signature(void)
 776 {
 777         if (signature && *signature)
 778                 printf("-- \n%s\n\n", signature);
 779 }
 780
 781 static void add_branch_description(struct strbuf *buf, const char *branch_name)
 782 {
 783         struct strbuf desc = STRBUF_INIT;
 784         if (!branch_name || !*branch_name)
 785                 return;
 786         read_branch_desc(&desc, branch_name);
 787         if (desc.len) {
 788                 strbuf_addch(buf, '\n');
 789                 strbuf_add(buf, desc.buf, desc.len);
 790                 strbuf_addch(buf, '\n');
 791         }
 792 }
 793
 794 static void make_cover_letter(struct rev_info *rev, int use_stdout,
 795                               struct commit *origin,
 796                               int nr, struct commit **list, struct commit *head,
 797                               const char *branch_name,
 798                               int quiet)
 799 {
 800         const char *committer;
 801         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
 802         const char *msg;
 803         struct shortlog log;
 804         struct strbuf sb = STRBUF_INIT;
 805         int i;
 806         const char *encoding = "UTF-8";
 807         struct diff_options opts;
 808         int need_8bit_cte = 0;
 809         struct pretty_print_context pp = {0};
 810
 811         if (rev->commit_format != CMIT_FMT_EMAIL)
 812                 die(_("Cover letter needs email format"));
 813
 814         committer = git_committer_info(0);
 815
 816         if (!use_stdout &&
 817             reopen_stdout(NULL, rev->numbered_files ? NULL : "cover-letter", rev, quiet))
 818                 return;
 819
 820         log_write_email_headers(rev, head, &pp.subject, &pp.after_subject,
 821                                 &need_8bit_cte);
 822
 823         for (i = 0; !need_8bit_cte && i < nr; i++)
 824                 if (has_non_ascii(list[i]->buffer))
 825                         need_8bit_cte = 1;
 826
 827         msg = body;
 828         pp.fmt = CMIT_FMT_EMAIL;
 829         pp.date_mode = DATE_RFC2822;
 830         pp_user_info(&pp, NULL, &sb, committer, encoding);
 831         pp_title_line(&pp, &msg, &sb, encoding, need_8bit_cte);
 832         pp_remainder(&pp, &msg, &sb, 0);
 833         add_branch_description(&sb, branch_name);
 834         printf("%s\n", sb.buf);
 835
 836         strbuf_release(&sb);
 837
 838         shortlog_init(&log);
 839         log.wrap_lines = 1;
 840         log.wrap = 72;
 841         log.in1 = 2;
 842         log.in2 = 4;
 843         for (i = 0; i < nr; i++)
 844                 shortlog_add_commit(&log, list[i]);
 845
 846         shortlog_output(&log);
 847
 848         /*
 849          * We can only do diffstat with a unique reference point
 850          */
 851         if (!origin)
 852                 return;
 853
 854         memcpy(&opts, &rev->diffopt, sizeof(opts));
 855         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
 856
 857         diff_setup_done(&opts);
 858
 859         diff_tree_sha1(origin->tree->object.sha1,
 860                        head->tree->object.sha1,
 861                        "", &opts);
 862         diffcore_std(&opts);
 863         diff_flush(&opts);
 864
 865         printf("\n");
 866         print_signature();
 867 }
 868
 869 static const char *clean_message_id(const char *msg_id)
 870 {
 871         char ch;
 872         const char *a, *z, *m;
 873
 874         m = msg_id;
 875         while ((ch = *m) && (isspace(ch) || (ch == '<')))
 876                 m++;
 877         a = m;
 878         z = NULL;
 879         while ((ch = *m)) {
 880                 if (!isspace(ch) && (ch != '>'))
 881                         z = m;
 882                 m++;
 883         }
 884         if (!z)
 885                 die(_("insane in-reply-to: %s"), msg_id);
 886         if (++z == m)
 887                 return a;
 888         return xmemdupz(a, z - a);
 889 }
 890
 891 static const char *set_outdir(const char *prefix, const char *output_directory)
 892 {
 893         if (output_directory && is_absolute_path(output_directory))
 894                 return output_directory;
 895
 896         if (!prefix || !*prefix) {
 897                 if (output_directory)
 898                         return output_directory;
 899                 /* The user did not explicitly ask for "./" */
 900                 outdir_offset = 2;
 901                 return "./";
 902         }
 903
 904         outdir_offset = strlen(prefix);
 905         if (!output_directory)
 906                 return prefix;
 907
 908         return xstrdup(prefix_filename(prefix, outdir_offset,
 909                                        output_directory));
 910 }
 911
 912 static const char * const builtin_format_patch_usage[] = {
 913         N_("git format-patch [options] [<since> | <revision range>]"),
 914         NULL
 915 };
 916
 917 static int keep_subject = 0;
 918
 919 static int keep_callback(const struct option *opt, const char *arg, int unset)
 920 {
 921         ((struct rev_info *)opt->value)->total = -1;
 922         keep_subject = 1;
 923         return 0;
 924 }
 925
 926 static int subject_prefix = 0;
 927
 928 static int subject_prefix_callback(const struct option *opt, const char *arg,
 929                             int unset)
 930 {
 931         subject_prefix = 1;
 932         ((struct rev_info *)opt->value)->subject_prefix = arg;
 933         return 0;
 934 }
 935
 936 static int numbered_cmdline_opt = 0;
 937
 938 static int numbered_callback(const struct option *opt, const char *arg,
 939                              int unset)
 940 {
 941         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
 942         if (unset)
 943                 auto_number =  0;
 944         return 0;
 945 }
 946
 947 static int no_numbered_callback(const struct option *opt, const char *arg,
 948                                 int unset)
 949 {
 950         return numbered_callback(opt, arg, 1);
 951 }
 952
 953 static int output_directory_callback(const struct option *opt, const char *arg,
 954                               int unset)
 955 {
 956         const char **dir = (const char **)opt->value;
 957         if (*dir)
 958                 die(_("Two output directories?"));
 959         *dir = arg;
 960         return 0;
 961 }
 962
 963 static int thread_callback(const struct option *opt, const char *arg, int unset)
 964 {
 965         int *thread = (int *)opt->value;
 966         if (unset)
 967                 *thread = 0;
 968         else if (!arg || !strcmp(arg, "shallow"))
 969                 *thread = THREAD_SHALLOW;
 970         else if (!strcmp(arg, "deep"))
 971                 *thread = THREAD_DEEP;
 972         else
 973                 return 1;
 974         return 0;
 975 }
 976
 977 static int attach_callback(const struct option *opt, const char *arg, int unset)
 978 {
 979         struct rev_info *rev = (struct rev_info *)opt->value;
 980         if (unset)
 981                 rev->mime_boundary = NULL;
 982         else if (arg)
 983                 rev->mime_boundary = arg;
 984         else
 985                 rev->mime_boundary = git_version_string;
 986         rev->no_inline = unset ? 0 : 1;
 987         return 0;
 988 }
 989
 990 static int inline_callback(const struct option *opt, const char *arg, int unset)
 991 {
 992         struct rev_info *rev = (struct rev_info *)opt->value;
 993         if (unset)
 994                 rev->mime_boundary = NULL;
 995         else if (arg)
 996                 rev->mime_boundary = arg;
 997         else
 998                 rev->mime_boundary = git_version_string;
 999         rev->no_inline = 0;
1000         return 0;
1001 }
1002
1003 static int header_callback(const struct option *opt, const char *arg, int unset)
1004 {
1005         if (unset) {
1006                 string_list_clear(&extra_hdr, 0);
1007                 string_list_clear(&extra_to, 0);
1008                 string_list_clear(&extra_cc, 0);
1009         } else {
1010             add_header(arg);
1011         }
1012         return 0;
1013 }
1014
1015 static int to_callback(const struct option *opt, const char *arg, int unset)
1016 {
1017         if (unset)
1018                 string_list_clear(&extra_to, 0);
1019         else
1020                 string_list_append(&extra_to, arg);
1021         return 0;
1022 }
1023
1024 static int cc_callback(const struct option *opt, const char *arg, int unset)
1025 {
1026         if (unset)
1027                 string_list_clear(&extra_cc, 0);
1028         else
1029                 string_list_append(&extra_cc, arg);
1030         return 0;
1031 }
1032
1033 static char *find_branch_name(struct rev_info *rev)
1034 {
1035         int i, positive = -1;
1036         unsigned char branch_sha1[20];
1037         const unsigned char *tip_sha1;
1038         const char *ref;
1039         char *full_ref, *branch = NULL;
1040
1041         for (i = 0; i < rev->cmdline.nr; i++) {
1042                 if (rev->cmdline.rev[i].flags & UNINTERESTING)
1043                         continue;
1044                 if (positive < 0)
1045                         positive = i;
1046                 else
1047                         return NULL;
1048         }
1049         if (0 <= positive) {
1050                 ref = rev->cmdline.rev[positive].name;
1051                 tip_sha1 = rev->cmdline.rev[positive].item->sha1;
1052         } else if (!rev->cmdline.nr && rev->pending.nr == 1 &&
1053                    !strcmp(rev->pending.objects[0].name, "HEAD")) {
1054                 /*
1055                  * No actual ref from command line, but "HEAD" from
1056                  * rev->def was added in setup_revisions()
1057                  * e.g. format-patch --cover-letter -12
1058                  */
1059                 ref = "HEAD";
1060                 tip_sha1 = rev->pending.objects[0].item->sha1;
1061         } else {
1062                 return NULL;
1063         }
1064         if (dwim_ref(ref, strlen(ref), branch_sha1, &full_ref) &&
1065             !prefixcmp(full_ref, "refs/heads/") &&
1066             !hashcmp(tip_sha1, branch_sha1))
1067                 branch = xstrdup(full_ref + strlen("refs/heads/"));
1068         free(full_ref);
1069         return branch;
1070 }
1071
1072 int cmd_format_patch(int argc, const char **argv, const char *prefix)
1073 {
1074         struct commit *commit;
1075         struct commit **list = NULL;
1076         struct rev_info rev;
1077         struct setup_revision_opt s_r_opt;
1078         int nr = 0, total, i;
1079         int use_stdout = 0;
1080         int start_number = -1;
1081         int just_numbers = 0;
1082         int ignore_if_in_upstream = 0;
1083         int cover_letter = 0;
1084         int boundary_count = 0;
1085         int no_binary_diff = 0;
1086         struct commit *origin = NULL, *head = NULL;
1087         const char *in_reply_to = NULL;
1088         struct patch_ids ids;
1089         char *add_signoff = NULL;
1090         struct strbuf buf = STRBUF_INIT;
1091         int use_patch_format = 0;
1092         int quiet = 0;
1093         int reroll_count = -1;
1094         char *branch_name = NULL;
1095         const struct option builtin_format_patch_options[] = {
1096                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
1097                             N_("use [PATCH n/m] even with a single patch"),
1098                             PARSE_OPT_NOARG, numbered_callback },
1099                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
1100                             N_("use [PATCH] even with multiple patches"),
1101                             PARSE_OPT_NOARG, no_numbered_callback },
1102                 OPT_BOOLEAN('s', "signoff", &do_signoff, N_("add Signed-off-by:")),
1103                 OPT_BOOLEAN(0, "stdout", &use_stdout,
1104                             N_("print patches to standard out")),
1105                 OPT_BOOLEAN(0, "cover-letter", &cover_letter,
1106                             N_("generate a cover letter")),
1107                 OPT_BOOLEAN(0, "numbered-files", &just_numbers,
1108                             N_("use simple number sequence for output file names")),
1109                 OPT_STRING(0, "suffix", &fmt_patch_suffix, N_("sfx"),
1110                             N_("use <sfx> instead of '.patch'")),
1111                 OPT_INTEGER(0, "start-number", &start_number,
1112                             N_("start numbering patches at <n> instead of 1")),
1113                 OPT_INTEGER('v', "reroll-count", &reroll_count,
1114                             N_("mark the series as Nth re-roll")),
1115                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, N_("prefix"),
1116                             N_("Use [<prefix>] instead of [PATCH]"),
1117                             PARSE_OPT_NONEG, subject_prefix_callback },
1118                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
1119                             N_("dir"), N_("store resulting files in <dir>"),
1120                             PARSE_OPT_NONEG, output_directory_callback },
1121                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
1122                             N_("don't strip/add [PATCH]"),
1123                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
1124                 OPT_BOOLEAN(0, "no-binary", &no_binary_diff,
1125                             N_("don't output binary diffs")),
1126                 OPT_BOOLEAN(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
1127                             N_("don't include a patch matching a commit upstream")),
1128                 { OPTION_BOOLEAN, 'p', "no-stat", &use_patch_format, NULL,
1129                   N_("show patch format instead of default (patch + stat)"),
1130                   PARSE_OPT_NONEG | PARSE_OPT_NOARG },
1131                 OPT_GROUP(N_("Messaging")),
1132                 { OPTION_CALLBACK, 0, "add-header", NULL, N_("header"),
1133                             N_("add email header"), 0, header_callback },
1134                 { OPTION_CALLBACK, 0, "to", NULL, N_("email"), N_("add To: header"),
1135                             0, to_callback },
1136                 { OPTION_CALLBACK, 0, "cc", NULL, N_("email"), N_("add Cc: header"),
1137                             0, cc_callback },
1138                 OPT_STRING(0, "in-reply-to", &in_reply_to, N_("message-id"),
1139                             N_("make first mail a reply to <message-id>")),
1140                 { OPTION_CALLBACK, 0, "attach", &rev, N_("boundary"),
1141                             N_("attach the patch"), PARSE_OPT_OPTARG,
1142                             attach_callback },
1143                 { OPTION_CALLBACK, 0, "inline", &rev, N_("boundary"),
1144                             N_("inline the patch"),
1145                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
1146                             inline_callback },
1147                 { OPTION_CALLBACK, 0, "thread", &thread, N_("style"),
1148                             N_("enable message threading, styles: shallow, deep"),
1149                             PARSE_OPT_OPTARG, thread_callback },
1150                 OPT_STRING(0, "signature", &signature, N_("signature"),
1151                             N_("add a signature")),
1152                 OPT_BOOLEAN(0, "quiet", &quiet,
1153                             N_("don't print the patch filenames")),
1154                 OPT_END()
1155         };
1156
1157         extra_hdr.strdup_strings = 1;
1158         extra_to.strdup_strings = 1;
1159         extra_cc.strdup_strings = 1;
1160         init_grep_defaults();
1161         git_config(git_format_config, NULL);
1162         init_revisions(&rev, prefix);
1163         rev.commit_format = CMIT_FMT_EMAIL;
1164         rev.verbose_header = 1;
1165         rev.diff = 1;
1166         rev.max_parents = 1;
1167         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
1168         rev.subject_prefix = fmt_patch_subject_prefix;
1169         memset(&s_r_opt, 0, sizeof(s_r_opt));
1170         s_r_opt.def = "HEAD";
1171         s_r_opt.revarg_opt = REVARG_COMMITTISH;
1172
1173         if (default_attach) {
1174                 rev.mime_boundary = default_attach;
1175                 rev.no_inline = 1;
1176         }
1177
1178         /*
1179          * Parse the arguments before setup_revisions(), or something
1180          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1181          * possibly a valid SHA1.
1182          */
1183         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1184                              builtin_format_patch_usage,
1185                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1186                              PARSE_OPT_KEEP_DASHDASH);
1187
1188         if (0 < reroll_count) {
1189                 struct strbuf sprefix = STRBUF_INIT;
1190                 strbuf_addf(&sprefix, "%s v%d",
1191                             rev.subject_prefix, reroll_count);
1192                 rev.reroll_count = reroll_count;
1193                 rev.subject_prefix = strbuf_detach(&sprefix, NULL);
1194         }
1195
1196         if (do_signoff) {
1197                 const char *committer;
1198                 const char *endpos;
1199                 committer = git_committer_info(IDENT_STRICT);
1200                 endpos = strchr(committer, '>');
1201                 if (!endpos)
1202                         die(_("bogus committer info %s"), committer);
1203                 add_signoff = xmemdupz(committer, endpos - committer + 1);
1204         }
1205
1206         for (i = 0; i < extra_hdr.nr; i++) {
1207                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1208                 strbuf_addch(&buf, '\n');
1209         }
1210
1211         if (extra_to.nr)
1212                 strbuf_addstr(&buf, "To: ");
1213         for (i = 0; i < extra_to.nr; i++) {
1214                 if (i)
1215                         strbuf_addstr(&buf, "    ");
1216                 strbuf_addstr(&buf, extra_to.items[i].string);
1217                 if (i + 1 < extra_to.nr)
1218                         strbuf_addch(&buf, ',');
1219                 strbuf_addch(&buf, '\n');
1220         }
1221
1222         if (extra_cc.nr)
1223                 strbuf_addstr(&buf, "Cc: ");
1224         for (i = 0; i < extra_cc.nr; i++) {
1225                 if (i)
1226                         strbuf_addstr(&buf, "    ");
1227                 strbuf_addstr(&buf, extra_cc.items[i].string);
1228                 if (i + 1 < extra_cc.nr)
1229                         strbuf_addch(&buf, ',');
1230                 strbuf_addch(&buf, '\n');
1231         }
1232
1233         rev.extra_headers = strbuf_detach(&buf, NULL);
1234
1235         if (start_number < 0)
1236                 start_number = 1;
1237
1238         /*
1239          * If numbered is set solely due to format.numbered in config,
1240          * and it would conflict with --keep-subject (-k) from the
1241          * command line, reset "numbered".
1242          */
1243         if (numbered && keep_subject && !numbered_cmdline_opt)
1244                 numbered = 0;
1245
1246         if (numbered && keep_subject)
1247                 die (_("-n and -k are mutually exclusive."));
1248         if (keep_subject && subject_prefix)
1249                 die (_("--subject-prefix and -k are mutually exclusive."));
1250         rev.preserve_subject = keep_subject;
1251
1252         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1253         if (argc > 1)
1254                 die (_("unrecognized argument: %s"), argv[1]);
1255
1256         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1257                 die(_("--name-only does not make sense"));
1258         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1259                 die(_("--name-status does not make sense"));
1260         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1261                 die(_("--check does not make sense"));
1262
1263         if (!use_patch_format &&
1264                 (!rev.diffopt.output_format ||
1265                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1266                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1267
1268         /* Always generate a patch */
1269         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1270
1271         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1272                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1273
1274         if (rev.show_notes)
1275                 init_display_notes(&rev.notes_opt);
1276
1277         if (!use_stdout)
1278                 output_directory = set_outdir(prefix, output_directory);
1279         else
1280                 setup_pager();
1281
1282         if (output_directory) {
1283                 if (use_stdout)
1284                         die(_("standard output, or directory, which one?"));
1285                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1286                         die_errno(_("Could not create directory '%s'"),
1287                                   output_directory);
1288         }
1289
1290         if (rev.pending.nr == 1) {
1291                 if (rev.max_count < 0 && !rev.show_root_diff) {
1292                         /*
1293                          * This is traditional behaviour of "git format-patch
1294                          * origin" that prepares what the origin side still
1295                          * does not have.
1296                          */
1297                         unsigned char sha1[20];
1298                         const char *ref;
1299
1300                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1301                         add_head_to_pending(&rev);
1302                         ref = resolve_ref_unsafe("HEAD", sha1, 1, NULL);
1303                         if (ref && !prefixcmp(ref, "refs/heads/"))
1304                                 branch_name = xstrdup(ref + strlen("refs/heads/"));
1305                         else
1306                                 branch_name = xstrdup(""); /* no branch */
1307                 }
1308                 /*
1309                  * Otherwise, it is "format-patch -22 HEAD", and/or
1310                  * "format-patch --root HEAD".  The user wants
1311                  * get_revision() to do the usual traversal.
1312                  */
1313         }
1314
1315         /*
1316          * We cannot move this anywhere earlier because we do want to
1317          * know if --root was given explicitly from the command line.
1318          */
1319         rev.show_root_diff = 1;
1320
1321         if (cover_letter) {
1322                 /*
1323                  * NEEDSWORK:randomly pick one positive commit to show
1324                  * diffstat; this is often the tip and the command
1325                  * happens to do the right thing in most cases, but a
1326                  * complex command like "--cover-letter a b c ^bottom"
1327                  * picks "c" and shows diffstat between bottom..c
1328                  * which may not match what the series represents at
1329                  * all and totally broken.
1330                  */
1331                 int i;
1332                 for (i = 0; i < rev.pending.nr; i++) {
1333                         struct object *o = rev.pending.objects[i].item;
1334                         if (!(o->flags & UNINTERESTING))
1335                                 head = (struct commit *)o;
1336                 }
1337                 /* There is nothing to show; it is not an error, though. */
1338                 if (!head)
1339                         return 0;
1340                 if (!branch_name)
1341                         branch_name = find_branch_name(&rev);
1342         }
1343
1344         if (ignore_if_in_upstream) {
1345                 /* Don't say anything if head and upstream are the same. */
1346                 if (rev.pending.nr == 2) {
1347                         struct object_array_entry *o = rev.pending.objects;
1348                         if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1349                                 return 0;
1350                 }
1351                 get_patch_ids(&rev, &ids);
1352         }
1353
1354         if (!use_stdout)
1355                 realstdout = xfdopen(xdup(1), "w");
1356
1357         if (prepare_revision_walk(&rev))
1358                 die(_("revision walk setup failed"));
1359         rev.boundary = 1;
1360         while ((commit = get_revision(&rev)) != NULL) {
1361                 if (commit->object.flags & BOUNDARY) {
1362                         boundary_count++;
1363                         origin = (boundary_count == 1) ? commit : NULL;
1364                         continue;
1365                 }
1366
1367                 if (ignore_if_in_upstream &&
1368                                 has_commit_patch_id(commit, &ids))
1369                         continue;
1370
1371                 nr++;
1372                 list = xrealloc(list, nr * sizeof(list[0]));
1373                 list[nr - 1] = commit;
1374         }
1375         total = nr;
1376         if (!keep_subject && auto_number && total > 1)
1377                 numbered = 1;
1378         if (numbered)
1379                 rev.total = total + start_number - 1;
1380         if (in_reply_to || thread || cover_letter)
1381                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1382         if (in_reply_to) {
1383                 const char *msgid = clean_message_id(in_reply_to);
1384                 string_list_append(rev.ref_message_ids, msgid);
1385         }
1386         rev.numbered_files = just_numbers;
1387         rev.patch_suffix = fmt_patch_suffix;
1388         if (cover_letter) {
1389                 if (thread)
1390                         gen_message_id(&rev, "cover");
1391                 make_cover_letter(&rev, use_stdout,
1392                                   origin, nr, list, head, branch_name, quiet);
1393                 total++;
1394                 start_number--;
1395         }
1396         rev.add_signoff = add_signoff;
1397         while (0 <= --nr) {
1398                 int shown;
1399                 commit = list[nr];
1400                 rev.nr = total - nr + (start_number - 1);
1401                 /* Make the second and subsequent mails replies to the first */
1402                 if (thread) {
1403                         /* Have we already had a message ID? */
1404                         if (rev.message_id) {
1405                                 /*
1406                                  * For deep threading: make every mail
1407                                  * a reply to the previous one, no
1408                                  * matter what other options are set.
1409                                  *
1410                                  * For shallow threading:
1411                                  *
1412                                  * Without --cover-letter and
1413                                  * --in-reply-to, make every mail a
1414                                  * reply to the one before.
1415                                  *
1416                                  * With --in-reply-to but no
1417                                  * --cover-letter, make every mail a
1418                                  * reply to the <reply-to>.
1419                                  *
1420                                  * With --cover-letter, make every
1421                                  * mail but the cover letter a reply
1422                                  * to the cover letter.  The cover
1423                                  * letter is a reply to the
1424                                  * --in-reply-to, if specified.
1425                                  */
1426                                 if (thread == THREAD_SHALLOW
1427                                     && rev.ref_message_ids->nr > 0
1428                                     && (!cover_letter || rev.nr > 1))
1429                                         free(rev.message_id);
1430                                 else
1431                                         string_list_append(rev.ref_message_ids,
1432                                                            rev.message_id);
1433                         }
1434                         gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
1435                 }
1436
1437                 if (!use_stdout &&
1438                     reopen_stdout(rev.numbered_files ? NULL : commit, NULL, &rev, quiet))
1439                         die(_("Failed to create output files"));
1440                 shown = log_tree_commit(&rev, commit);
1441                 free(commit->buffer);
1442                 commit->buffer = NULL;
1443
1444                 /* We put one extra blank line between formatted
1445                  * patches and this flag is used by log-tree code
1446                  * to see if it needs to emit a LF before showing
1447                  * the log; when using one file per patch, we do
1448                  * not want the extra blank line.
1449                  */
1450                 if (!use_stdout)
1451                         rev.shown_one = 0;
1452                 if (shown) {
1453                         if (rev.mime_boundary)
1454                                 printf("\n--%s%s--\n\n\n",
1455                                        mime_boundary_leader,
1456                                        rev.mime_boundary);
1457                         else
1458                                 print_signature();
1459                 }
1460                 if (!use_stdout)
1461                         fclose(stdout);
1462         }
1463         free(list);
1464         free(branch_name);
1465         string_list_clear(&extra_to, 0);
1466         string_list_clear(&extra_cc, 0);
1467         string_list_clear(&extra_hdr, 0);
1468         if (ignore_if_in_upstream)
1469                 free_patch_ids(&ids);
1470         return 0;
1471 }
1472
1473 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1474 {
1475         unsigned char sha1[20];
1476         if (get_sha1(arg, sha1) == 0) {
1477                 struct commit *commit = lookup_commit_reference(sha1);
1478                 if (commit) {
1479                         commit->object.flags |= flags;
1480                         add_pending_object(revs, &commit->object, arg);
1481                         return 0;
1482                 }
1483         }
1484         return -1;
1485 }
1486
1487 static const char * const cherry_usage[] = {
1488         N_("git cherry [-v] [<upstream> [<head> [<limit>]]]"),
1489         NULL
1490 };
1491
1492 static void print_commit(char sign, struct commit *commit, int verbose,
1493                          int abbrev)
1494 {
1495         if (!verbose) {
1496                 printf("%c %s\n", sign,
1497                        find_unique_abbrev(commit->object.sha1, abbrev));
1498         } else {
1499                 struct strbuf buf = STRBUF_INIT;
1500                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
1501                 printf("%c %s %s\n", sign,
1502                        find_unique_abbrev(commit->object.sha1, abbrev),
1503                        buf.buf);
1504                 strbuf_release(&buf);
1505         }
1506 }
1507
1508 int cmd_cherry(int argc, const char **argv, const char *prefix)
1509 {
1510         struct rev_info revs;
1511         struct patch_ids ids;
1512         struct commit *commit;
1513         struct commit_list *list = NULL;
1514         struct branch *current_branch;
1515         const char *upstream;
1516         const char *head = "HEAD";
1517         const char *limit = NULL;
1518         int verbose = 0, abbrev = 0;
1519
1520         struct option options[] = {
1521                 OPT__ABBREV(&abbrev),
1522                 OPT__VERBOSE(&verbose, N_("be verbose")),
1523                 OPT_END()
1524         };
1525
1526         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
1527
1528         switch (argc) {
1529         case 3:
1530                 limit = argv[2];
1531                 /* FALLTHROUGH */
1532         case 2:
1533                 head = argv[1];
1534                 /* FALLTHROUGH */
1535         case 1:
1536                 upstream = argv[0];
1537                 break;
1538         default:
1539                 current_branch = branch_get(NULL);
1540                 if (!current_branch || !current_branch->merge
1541                                         || !current_branch->merge[0]
1542                                         || !current_branch->merge[0]->dst) {
1543                         fprintf(stderr, _("Could not find a tracked"
1544                                         " remote branch, please"
1545                                         " specify <upstream> manually.\n"));
1546                         usage_with_options(cherry_usage, options);
1547                 }
1548
1549                 upstream = current_branch->merge[0]->dst;
1550         }
1551
1552         init_revisions(&revs, prefix);
1553         revs.max_parents = 1;
1554
1555         if (add_pending_commit(head, &revs, 0))
1556                 die(_("Unknown commit %s"), head);
1557         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1558                 die(_("Unknown commit %s"), upstream);
1559
1560         /* Don't say anything if head and upstream are the same. */
1561         if (revs.pending.nr == 2) {
1562                 struct object_array_entry *o = revs.pending.objects;
1563                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1564                         return 0;
1565         }
1566
1567         get_patch_ids(&revs, &ids);
1568
1569         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1570                 die(_("Unknown commit %s"), limit);
1571
1572         /* reverse the list of commits */
1573         if (prepare_revision_walk(&revs))
1574                 die(_("revision walk setup failed"));
1575         while ((commit = get_revision(&revs)) != NULL) {
1576                 commit_list_insert(commit, &list);
1577         }
1578
1579         while (list) {
1580                 char sign = '+';
1581
1582                 commit = list->item;
1583                 if (has_commit_patch_id(commit, &ids))
1584                         sign = '-';
1585                 print_commit(sign, commit, verbose, abbrev);
1586                 list = list->next;
1587         }
1588
1589         free_patch_ids(&ids);
1590         return 0;
1591 }