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