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 "config.h"
   9 #include "refs.h"
  10 #include "object-store.h"
  11 #include "color.h"
  12 #include "commit.h"
  13 #include "diff.h"
  14 #include "revision.h"
  15 #include "log-tree.h"
  16 #include "builtin.h"
  17 #include "tag.h"
  18 #include "reflog-walk.h"
  19 #include "patch-ids.h"
  20 #include "run-command.h"
  21 #include "shortlog.h"
  22 #include "remote.h"
  23 #include "string-list.h"
  24 #include "parse-options.h"
  25 #include "line-log.h"
  26 #include "branch.h"
  27 #include "streaming.h"
  28 #include "version.h"
  29 #include "mailmap.h"
  30 #include "gpg-interface.h"
  31 #include "progress.h"
  32 #include "commit-slab.h"
  33 #include "repository.h"
  34 #include "commit-reach.h"
  35 #include "interdiff.h"
  36 #include "range-diff.h"
  37
  38 #define MAIL_DEFAULT_WRAP 72
  39
  40 /* Set a default date-time format for git log ("log.date" config variable) */
  41 static const char *default_date_mode = NULL;
  42
  43 static int default_abbrev_commit;
  44 static int default_show_root = 1;
  45 static int default_follow;
  46 static int default_show_signature;
  47 static int decoration_style;
  48 static int decoration_given;
  49 static int use_mailmap_config;
  50 static const char *fmt_patch_subject_prefix = "PATCH";
  51 static const char *fmt_pretty;
  52
  53 static const char * const builtin_log_usage[] = {
  54         N_("git log [<options>] [<revision-range>] [[--] <path>...]"),
  55         N_("git show [<options>] <object>..."),
  56         NULL
  57 };
  58
  59 struct line_opt_callback_data {
  60         struct rev_info *rev;
  61         const char *prefix;
  62         struct string_list args;
  63 };
  64
  65 static int auto_decoration_style(void)
  66 {
  67         return (isatty(1) || pager_in_use()) ? DECORATE_SHORT_REFS : 0;
  68 }
  69
  70 static int parse_decoration_style(const char *value)
  71 {
  72         switch (git_parse_maybe_bool(value)) {
  73         case 1:
  74                 return DECORATE_SHORT_REFS;
  75         case 0:
  76                 return 0;
  77         default:
  78                 break;
  79         }
  80         if (!strcmp(value, "full"))
  81                 return DECORATE_FULL_REFS;
  82         else if (!strcmp(value, "short"))
  83                 return DECORATE_SHORT_REFS;
  84         else if (!strcmp(value, "auto"))
  85                 return auto_decoration_style();
  86         return -1;
  87 }
  88
  89 static int decorate_callback(const struct option *opt, const char *arg, int unset)
  90 {
  91         if (unset)
  92                 decoration_style = 0;
  93         else if (arg)
  94                 decoration_style = parse_decoration_style(arg);
  95         else
  96                 decoration_style = DECORATE_SHORT_REFS;
  97
  98         if (decoration_style < 0)
  99                 die(_("invalid --decorate option: %s"), arg);
 100
 101         decoration_given = 1;
 102
 103         return 0;
 104 }
 105
 106 static int log_line_range_callback(const struct option *option, const char *arg, int unset)
 107 {
 108         struct line_opt_callback_data *data = option->value;
 109
 110         BUG_ON_OPT_NEG(unset);
 111
 112         if (!arg)
 113                 return -1;
 114
 115         data->rev->line_level_traverse = 1;
 116         string_list_append(&data->args, arg);
 117
 118         return 0;
 119 }
 120
 121 static void init_log_defaults(void)
 122 {
 123         init_grep_defaults(the_repository);
 124         init_diff_ui_defaults();
 125
 126         decoration_style = auto_decoration_style();
 127 }
 128
 129 static void cmd_log_init_defaults(struct rev_info *rev)
 130 {
 131         if (fmt_pretty)
 132                 get_commit_format(fmt_pretty, rev);
 133         if (default_follow)
 134                 rev->diffopt.flags.default_follow_renames = 1;
 135         rev->verbose_header = 1;
 136         rev->diffopt.flags.recursive = 1;
 137         rev->diffopt.stat_width = -1; /* use full terminal width */
 138         rev->diffopt.stat_graph_width = -1; /* respect statGraphWidth config */
 139         rev->abbrev_commit = default_abbrev_commit;
 140         rev->show_root_diff = default_show_root;
 141         rev->subject_prefix = fmt_patch_subject_prefix;
 142         rev->show_signature = default_show_signature;
 143         rev->diffopt.flags.allow_textconv = 1;
 144
 145         if (default_date_mode)
 146                 parse_date_format(default_date_mode, &rev->date_mode);
 147 }
 148
 149 static void cmd_log_init_finish(int argc, const char **argv, const char *prefix,
 150                          struct rev_info *rev, struct setup_revision_opt *opt)
 151 {
 152         struct userformat_want w;
 153         int quiet = 0, source = 0, mailmap = 0;
 154         static struct line_opt_callback_data line_cb = {NULL, NULL, STRING_LIST_INIT_DUP};
 155         static struct string_list decorate_refs_exclude = STRING_LIST_INIT_NODUP;
 156         static struct string_list decorate_refs_include = STRING_LIST_INIT_NODUP;
 157         struct decoration_filter decoration_filter = {&decorate_refs_include,
 158                                                       &decorate_refs_exclude};
 159         static struct revision_sources revision_sources;
 160
 161         const struct option builtin_log_options[] = {
 162                 OPT__QUIET(&quiet, N_("suppress diff output")),
 163                 OPT_BOOL(0, "source", &source, N_("show source")),
 164                 OPT_BOOL(0, "use-mailmap", &mailmap, N_("Use mail map file")),
 165                 OPT_STRING_LIST(0, "decorate-refs", &decorate_refs_include,
 166                                 N_("pattern"), N_("only decorate refs that match <pattern>")),
 167                 OPT_STRING_LIST(0, "decorate-refs-exclude", &decorate_refs_exclude,
 168                                 N_("pattern"), N_("do not decorate refs that match <pattern>")),
 169                 { OPTION_CALLBACK, 0, "decorate", NULL, NULL, N_("decorate options"),
 170                   PARSE_OPT_OPTARG, decorate_callback},
 171                 OPT_CALLBACK('L', NULL, &line_cb, "n,m:file",
 172                              N_("Process line range n,m in file, counting from 1"),
 173                              log_line_range_callback),
 174                 OPT_END()
 175         };
 176
 177         line_cb.rev = rev;
 178         line_cb.prefix = prefix;
 179
 180         mailmap = use_mailmap_config;
 181         argc = parse_options(argc, argv, prefix,
 182                              builtin_log_options, builtin_log_usage,
 183                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
 184                              PARSE_OPT_KEEP_DASHDASH);
 185
 186         if (quiet)
 187                 rev->diffopt.output_format |= DIFF_FORMAT_NO_OUTPUT;
 188         argc = setup_revisions(argc, argv, rev, opt);
 189
 190         /* Any arguments at this point are not recognized */
 191         if (argc > 1)
 192                 die(_("unrecognized argument: %s"), argv[1]);
 193
 194         memset(&w, 0, sizeof(w));
 195         userformat_find_requirements(NULL, &w);
 196
 197         if (!rev->show_notes_given && (!rev->pretty_given || w.notes))
 198                 rev->show_notes = 1;
 199         if (rev->show_notes)
 200                 init_display_notes(&rev->notes_opt);
 201
 202         if ((rev->diffopt.pickaxe_opts & DIFF_PICKAXE_KINDS_MASK) ||
 203             rev->diffopt.filter || rev->diffopt.flags.follow_renames)
 204                 rev->always_show_header = 0;
 205
 206         if (source) {
 207                 init_revision_sources(&revision_sources);
 208                 rev->sources = &revision_sources;
 209         }
 210
 211         if (mailmap) {
 212                 rev->mailmap = xcalloc(1, sizeof(struct string_list));
 213                 read_mailmap(rev->mailmap, NULL);
 214         }
 215
 216         if (rev->pretty_given && rev->commit_format == CMIT_FMT_RAW) {
 217                 /*
 218                  * "log --pretty=raw" is special; ignore UI oriented
 219                  * configuration variables such as decoration.
 220                  */
 221                 if (!decoration_given)
 222                         decoration_style = 0;
 223                 if (!rev->abbrev_commit_given)
 224                         rev->abbrev_commit = 0;
 225         }
 226
 227         if (decoration_style) {
 228                 rev->show_decorations = 1;
 229                 load_ref_decorations(&decoration_filter, decoration_style);
 230         }
 231
 232         if (rev->line_level_traverse)
 233                 line_log_init(rev, line_cb.prefix, &line_cb.args);
 234
 235         setup_pager();
 236 }
 237
 238 static void cmd_log_init(int argc, const char **argv, const char *prefix,
 239                          struct rev_info *rev, struct setup_revision_opt *opt)
 240 {
 241         cmd_log_init_defaults(rev);
 242         cmd_log_init_finish(argc, argv, prefix, rev, opt);
 243 }
 244
 245 /*
 246  * This gives a rough estimate for how many commits we
 247  * will print out in the list.
 248  */
 249 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
 250 {
 251         int n = 0;
 252
 253         while (list) {
 254                 struct commit *commit = list->item;
 255                 unsigned int flags = commit->object.flags;
 256                 list = list->next;
 257                 if (!(flags & (TREESAME | UNINTERESTING)))
 258                         n++;
 259         }
 260         return n;
 261 }
 262
 263 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
 264 {
 265         if (rev->shown_one) {
 266                 rev->shown_one = 0;
 267                 if (rev->commit_format != CMIT_FMT_ONELINE)
 268                         putchar(rev->diffopt.line_termination);
 269         }
 270         fprintf(rev->diffopt.file, _("Final output: %d %s\n"), nr, stage);
 271 }
 272
 273 static struct itimerval early_output_timer;
 274
 275 static void log_show_early(struct rev_info *revs, struct commit_list *list)
 276 {
 277         int i = revs->early_output, close_file = revs->diffopt.close_file;
 278         int show_header = 1;
 279
 280         revs->diffopt.close_file = 0;
 281         sort_in_topological_order(&list, revs->sort_order);
 282         while (list && i) {
 283                 struct commit *commit = list->item;
 284                 switch (simplify_commit(revs, commit)) {
 285                 case commit_show:
 286                         if (show_header) {
 287                                 int n = estimate_commit_count(revs, list);
 288                                 show_early_header(revs, "incomplete", n);
 289                                 show_header = 0;
 290                         }
 291                         log_tree_commit(revs, commit);
 292                         i--;
 293                         break;
 294                 case commit_ignore:
 295                         break;
 296                 case commit_error:
 297                         if (close_file)
 298                                 fclose(revs->diffopt.file);
 299                         return;
 300                 }
 301                 list = list->next;
 302         }
 303
 304         /* Did we already get enough commits for the early output? */
 305         if (!i) {
 306                 if (close_file)
 307                         fclose(revs->diffopt.file);
 308                 return;
 309         }
 310
 311         /*
 312          * ..if no, then repeat it twice a second until we
 313          * do.
 314          *
 315          * NOTE! We don't use "it_interval", because if the
 316          * reader isn't listening, we want our output to be
 317          * throttled by the writing, and not have the timer
 318          * trigger every second even if we're blocked on a
 319          * reader!
 320          */
 321         early_output_timer.it_value.tv_sec = 0;
 322         early_output_timer.it_value.tv_usec = 500000;
 323         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 324 }
 325
 326 static void early_output(int signal)
 327 {
 328         show_early_output = log_show_early;
 329 }
 330
 331 static void setup_early_output(struct rev_info *rev)
 332 {
 333         struct sigaction sa;
 334
 335         /*
 336          * Set up the signal handler, minimally intrusively:
 337          * we only set a single volatile integer word (not
 338          * using sigatomic_t - trying to avoid unnecessary
 339          * system dependencies and headers), and using
 340          * SA_RESTART.
 341          */
 342         memset(&sa, 0, sizeof(sa));
 343         sa.sa_handler = early_output;
 344         sigemptyset(&sa.sa_mask);
 345         sa.sa_flags = SA_RESTART;
 346         sigaction(SIGALRM, &sa, NULL);
 347
 348         /*
 349          * If we can get the whole output in less than a
 350          * tenth of a second, don't even bother doing the
 351          * early-output thing..
 352          *
 353          * This is a one-time-only trigger.
 354          */
 355         early_output_timer.it_value.tv_sec = 0;
 356         early_output_timer.it_value.tv_usec = 100000;
 357         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 358 }
 359
 360 static void finish_early_output(struct rev_info *rev)
 361 {
 362         int n = estimate_commit_count(rev, rev->commits);
 363         signal(SIGALRM, SIG_IGN);
 364         show_early_header(rev, "done", n);
 365 }
 366
 367 static int cmd_log_walk(struct rev_info *rev)
 368 {
 369         struct commit *commit;
 370         int saved_nrl = 0;
 371         int saved_dcctc = 0, close_file = rev->diffopt.close_file;
 372
 373         if (rev->early_output)
 374                 setup_early_output(rev);
 375
 376         if (prepare_revision_walk(rev))
 377                 die(_("revision walk setup failed"));
 378
 379         if (rev->early_output)
 380                 finish_early_output(rev);
 381
 382         /*
 383          * For --check and --exit-code, the exit code is based on CHECK_FAILED
 384          * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
 385          * retain that state information if replacing rev->diffopt in this loop
 386          */
 387         rev->diffopt.close_file = 0;
 388         while ((commit = get_revision(rev)) != NULL) {
 389                 if (!log_tree_commit(rev, commit) && rev->max_count >= 0)
 390                         /*
 391                          * We decremented max_count in get_revision,
 392                          * but we didn't actually show the commit.
 393                          */
 394                         rev->max_count++;
 395                 if (!rev->reflog_info) {
 396                         /*
 397                          * We may show a given commit multiple times when
 398                          * walking the reflogs.
 399                          */
 400                         free_commit_buffer(commit);
 401                         free_commit_list(commit->parents);
 402                         commit->parents = NULL;
 403                 }
 404                 if (saved_nrl < rev->diffopt.needed_rename_limit)
 405                         saved_nrl = rev->diffopt.needed_rename_limit;
 406                 if (rev->diffopt.degraded_cc_to_c)
 407                         saved_dcctc = 1;
 408         }
 409         rev->diffopt.degraded_cc_to_c = saved_dcctc;
 410         rev->diffopt.needed_rename_limit = saved_nrl;
 411         if (close_file)
 412                 fclose(rev->diffopt.file);
 413
 414         if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
 415             rev->diffopt.flags.check_failed) {
 416                 return 02;
 417         }
 418         return diff_result_code(&rev->diffopt, 0);
 419 }
 420
 421 static int git_log_config(const char *var, const char *value, void *cb)
 422 {
 423         const char *slot_name;
 424
 425         if (!strcmp(var, "format.pretty"))
 426                 return git_config_string(&fmt_pretty, var, value);
 427         if (!strcmp(var, "format.subjectprefix"))
 428                 return git_config_string(&fmt_patch_subject_prefix, var, value);
 429         if (!strcmp(var, "log.abbrevcommit")) {
 430                 default_abbrev_commit = git_config_bool(var, value);
 431                 return 0;
 432         }
 433         if (!strcmp(var, "log.date"))
 434                 return git_config_string(&default_date_mode, var, value);
 435         if (!strcmp(var, "log.decorate")) {
 436                 decoration_style = parse_decoration_style(value);
 437                 if (decoration_style < 0)
 438                         decoration_style = 0; /* maybe warn? */
 439                 return 0;
 440         }
 441         if (!strcmp(var, "log.showroot")) {
 442                 default_show_root = git_config_bool(var, value);
 443                 return 0;
 444         }
 445         if (!strcmp(var, "log.follow")) {
 446                 default_follow = git_config_bool(var, value);
 447                 return 0;
 448         }
 449         if (skip_prefix(var, "color.decorate.", &slot_name))
 450                 return parse_decorate_color_config(var, slot_name, value);
 451         if (!strcmp(var, "log.mailmap")) {
 452                 use_mailmap_config = git_config_bool(var, value);
 453                 return 0;
 454         }
 455         if (!strcmp(var, "log.showsignature")) {
 456                 default_show_signature = git_config_bool(var, value);
 457                 return 0;
 458         }
 459
 460         if (grep_config(var, value, cb) < 0)
 461                 return -1;
 462         if (git_gpg_config(var, value, cb) < 0)
 463                 return -1;
 464         return git_diff_ui_config(var, value, cb);
 465 }
 466
 467 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 468 {
 469         struct rev_info rev;
 470         struct setup_revision_opt opt;
 471
 472         init_log_defaults();
 473         git_config(git_log_config, NULL);
 474
 475         repo_init_revisions(the_repository, &rev, prefix);
 476         rev.diff = 1;
 477         rev.simplify_history = 0;
 478         memset(&opt, 0, sizeof(opt));
 479         opt.def = "HEAD";
 480         opt.revarg_opt = REVARG_COMMITTISH;
 481         cmd_log_init(argc, argv, prefix, &rev, &opt);
 482         if (!rev.diffopt.output_format)
 483                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
 484         return cmd_log_walk(&rev);
 485 }
 486
 487 static void show_tagger(char *buf, int len, struct rev_info *rev)
 488 {
 489         struct strbuf out = STRBUF_INIT;
 490         struct pretty_print_context pp = {0};
 491
 492         pp.fmt = rev->commit_format;
 493         pp.date_mode = rev->date_mode;
 494         pp_user_info(&pp, "Tagger", &out, buf, get_log_output_encoding());
 495         fprintf(rev->diffopt.file, "%s", out.buf);
 496         strbuf_release(&out);
 497 }
 498
 499 static int show_blob_object(const struct object_id *oid, struct rev_info *rev, const char *obj_name)
 500 {
 501         struct object_id oidc;
 502         struct object_context obj_context;
 503         char *buf;
 504         unsigned long size;
 505
 506         fflush(rev->diffopt.file);
 507         if (!rev->diffopt.flags.textconv_set_via_cmdline ||
 508             !rev->diffopt.flags.allow_textconv)
 509                 return stream_blob_to_fd(1, oid, NULL, 0);
 510
 511         if (get_oid_with_context(obj_name, GET_OID_RECORD_PATH,
 512                                  &oidc, &obj_context))
 513                 die(_("Not a valid object name %s"), obj_name);
 514         if (!obj_context.path ||
 515             !textconv_object(the_repository, obj_context.path,
 516                              obj_context.mode, &oidc, 1, &buf, &size)) {
 517                 free(obj_context.path);
 518                 return stream_blob_to_fd(1, oid, NULL, 0);
 519         }
 520
 521         if (!buf)
 522                 die(_("git show %s: bad file"), obj_name);
 523
 524         write_or_die(1, buf, size);
 525         free(obj_context.path);
 526         return 0;
 527 }
 528
 529 static int show_tag_object(const struct object_id *oid, struct rev_info *rev)
 530 {
 531         unsigned long size;
 532         enum object_type type;
 533         char *buf = read_object_file(oid, &type, &size);
 534         int offset = 0;
 535
 536         if (!buf)
 537                 return error(_("Could not read object %s"), oid_to_hex(oid));
 538
 539         assert(type == OBJ_TAG);
 540         while (offset < size && buf[offset] != '\n') {
 541                 int new_offset = offset + 1;
 542                 while (new_offset < size && buf[new_offset++] != '\n')
 543                         ; /* do nothing */
 544                 if (starts_with(buf + offset, "tagger "))
 545                         show_tagger(buf + offset + 7,
 546                                     new_offset - offset - 7, rev);
 547                 offset = new_offset;
 548         }
 549
 550         if (offset < size)
 551                 fwrite(buf + offset, size - offset, 1, rev->diffopt.file);
 552         free(buf);
 553         return 0;
 554 }
 555
 556 static int show_tree_object(const struct object_id *oid,
 557                 struct strbuf *base,
 558                 const char *pathname, unsigned mode, int stage, void *context)
 559 {
 560         FILE *file = context;
 561         fprintf(file, "%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
 562         return 0;
 563 }
 564
 565 static void show_setup_revisions_tweak(struct rev_info *rev,
 566                                        struct setup_revision_opt *opt)
 567 {
 568         if (rev->ignore_merges) {
 569                 /* There was no "-m" on the command line */
 570                 rev->ignore_merges = 0;
 571                 if (!rev->first_parent_only && !rev->combine_merges) {
 572                         /* No "--first-parent", "-c", or "--cc" */
 573                         rev->combine_merges = 1;
 574                         rev->dense_combined_merges = 1;
 575                 }
 576         }
 577         if (!rev->diffopt.output_format)
 578                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
 579 }
 580
 581 int cmd_show(int argc, const char **argv, const char *prefix)
 582 {
 583         struct rev_info rev;
 584         struct object_array_entry *objects;
 585         struct setup_revision_opt opt;
 586         struct pathspec match_all;
 587         int i, count, ret = 0;
 588
 589         init_log_defaults();
 590         git_config(git_log_config, NULL);
 591
 592         memset(&match_all, 0, sizeof(match_all));
 593         repo_init_revisions(the_repository, &rev, prefix);
 594         rev.diff = 1;
 595         rev.always_show_header = 1;
 596         rev.no_walk = REVISION_WALK_NO_WALK_SORTED;
 597         rev.diffopt.stat_width = -1;    /* Scale to real terminal size */
 598
 599         memset(&opt, 0, sizeof(opt));
 600         opt.def = "HEAD";
 601         opt.tweak = show_setup_revisions_tweak;
 602         cmd_log_init(argc, argv, prefix, &rev, &opt);
 603
 604         if (!rev.no_walk)
 605                 return cmd_log_walk(&rev);
 606
 607         count = rev.pending.nr;
 608         objects = rev.pending.objects;
 609         for (i = 0; i < count && !ret; i++) {
 610                 struct object *o = objects[i].item;
 611                 const char *name = objects[i].name;
 612                 switch (o->type) {
 613                 case OBJ_BLOB:
 614                         ret = show_blob_object(&o->oid, &rev, name);
 615                         break;
 616                 case OBJ_TAG: {
 617                         struct tag *t = (struct tag *)o;
 618
 619                         if (rev.shown_one)
 620                                 putchar('\n');
 621                         fprintf(rev.diffopt.file, "%stag %s%s\n",
 622                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 623                                         t->tag,
 624                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 625                         ret = show_tag_object(&o->oid, &rev);
 626                         rev.shown_one = 1;
 627                         if (ret)
 628                                 break;
 629                         o = parse_object(the_repository, &t->tagged->oid);
 630                         if (!o)
 631                                 ret = error(_("Could not read object %s"),
 632                                             oid_to_hex(&t->tagged->oid));
 633                         objects[i].item = o;
 634                         i--;
 635                         break;
 636                 }
 637                 case OBJ_TREE:
 638                         if (rev.shown_one)
 639                                 putchar('\n');
 640                         fprintf(rev.diffopt.file, "%stree %s%s\n\n",
 641                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
 642                                         name,
 643                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 644                         read_tree_recursive((struct tree *)o, "", 0, 0, &match_all,
 645                                         show_tree_object, rev.diffopt.file);
 646                         rev.shown_one = 1;
 647                         break;
 648                 case OBJ_COMMIT:
 649                         rev.pending.nr = rev.pending.alloc = 0;
 650                         rev.pending.objects = NULL;
 651                         add_object_array(o, name, &rev.pending);
 652                         ret = cmd_log_walk(&rev);
 653                         break;
 654                 default:
 655                         ret = error(_("Unknown type: %d"), o->type);
 656                 }
 657         }
 658         free(objects);
 659         return ret;
 660 }
 661
 662 /*
 663  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
 664  */
 665 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
 666 {
 667         struct rev_info rev;
 668         struct setup_revision_opt opt;
 669
 670         init_log_defaults();
 671         git_config(git_log_config, NULL);
 672
 673         repo_init_revisions(the_repository, &rev, prefix);
 674         init_reflog_walk(&rev.reflog_info);
 675         rev.verbose_header = 1;
 676         memset(&opt, 0, sizeof(opt));
 677         opt.def = "HEAD";
 678         cmd_log_init_defaults(&rev);
 679         rev.abbrev_commit = 1;
 680         rev.commit_format = CMIT_FMT_ONELINE;
 681         rev.use_terminator = 1;
 682         rev.always_show_header = 1;
 683         cmd_log_init_finish(argc, argv, prefix, &rev, &opt);
 684
 685         return cmd_log_walk(&rev);
 686 }
 687
 688 static void log_setup_revisions_tweak(struct rev_info *rev,
 689                                       struct setup_revision_opt *opt)
 690 {
 691         if (rev->diffopt.flags.default_follow_renames &&
 692             rev->prune_data.nr == 1)
 693                 rev->diffopt.flags.follow_renames = 1;
 694
 695         /* Turn --cc/-c into -p --cc/-c when -p was not given */
 696         if (!rev->diffopt.output_format && rev->combine_merges)
 697                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
 698
 699         /* Turn -m on when --cc/-c was given */
 700         if (rev->combine_merges)
 701                 rev->ignore_merges = 0;
 702 }
 703
 704 int cmd_log(int argc, const char **argv, const char *prefix)
 705 {
 706         struct rev_info rev;
 707         struct setup_revision_opt opt;
 708
 709         init_log_defaults();
 710         git_config(git_log_config, NULL);
 711
 712         repo_init_revisions(the_repository, &rev, prefix);
 713         rev.always_show_header = 1;
 714         memset(&opt, 0, sizeof(opt));
 715         opt.def = "HEAD";
 716         opt.revarg_opt = REVARG_COMMITTISH;
 717         opt.tweak = log_setup_revisions_tweak;
 718         cmd_log_init(argc, argv, prefix, &rev, &opt);
 719         return cmd_log_walk(&rev);
 720 }
 721
 722 /* format-patch */
 723
 724 static const char *fmt_patch_suffix = ".patch";
 725 static int numbered = 0;
 726 static int auto_number = 1;
 727
 728 static char *default_attach = NULL;
 729
 730 static struct string_list extra_hdr = STRING_LIST_INIT_NODUP;
 731 static struct string_list extra_to = STRING_LIST_INIT_NODUP;
 732 static struct string_list extra_cc = STRING_LIST_INIT_NODUP;
 733
 734 static void add_header(const char *value)
 735 {
 736         struct string_list_item *item;
 737         int len = strlen(value);
 738         while (len && value[len - 1] == '\n')
 739                 len--;
 740
 741         if (!strncasecmp(value, "to: ", 4)) {
 742                 item = string_list_append(&extra_to, value + 4);
 743                 len -= 4;
 744         } else if (!strncasecmp(value, "cc: ", 4)) {
 745                 item = string_list_append(&extra_cc, value + 4);
 746                 len -= 4;
 747         } else {
 748                 item = string_list_append(&extra_hdr, value);
 749         }
 750
 751         item->string[len] = '\0';
 752 }
 753
 754 #define THREAD_SHALLOW 1
 755 #define THREAD_DEEP 2
 756 static int thread;
 757 static int do_signoff;
 758 static int base_auto;
 759 static char *from;
 760 static const char *signature = git_version_string;
 761 static const char *signature_file;
 762 static int config_cover_letter;
 763 static const char *config_output_directory;
 764
 765 enum {
 766         COVER_UNSET,
 767         COVER_OFF,
 768         COVER_ON,
 769         COVER_AUTO
 770 };
 771
 772 static int git_format_config(const char *var, const char *value, void *cb)
 773 {
 774         if (!strcmp(var, "format.headers")) {
 775                 if (!value)
 776                         die(_("format.headers without value"));
 777                 add_header(value);
 778                 return 0;
 779         }
 780         if (!strcmp(var, "format.suffix"))
 781                 return git_config_string(&fmt_patch_suffix, var, value);
 782         if (!strcmp(var, "format.to")) {
 783                 if (!value)
 784                         return config_error_nonbool(var);
 785                 string_list_append(&extra_to, value);
 786                 return 0;
 787         }
 788         if (!strcmp(var, "format.cc")) {
 789                 if (!value)
 790                         return config_error_nonbool(var);
 791                 string_list_append(&extra_cc, value);
 792                 return 0;
 793         }
 794         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff") ||
 795             !strcmp(var, "color.ui") || !strcmp(var, "diff.submodule")) {
 796                 return 0;
 797         }
 798         if (!strcmp(var, "format.numbered")) {
 799                 if (value && !strcasecmp(value, "auto")) {
 800                         auto_number = 1;
 801                         return 0;
 802                 }
 803                 numbered = git_config_bool(var, value);
 804                 auto_number = auto_number && numbered;
 805                 return 0;
 806         }
 807         if (!strcmp(var, "format.attach")) {
 808                 if (value && *value)
 809                         default_attach = xstrdup(value);
 810                 else
 811                         default_attach = xstrdup(git_version_string);
 812                 return 0;
 813         }
 814         if (!strcmp(var, "format.thread")) {
 815                 if (value && !strcasecmp(value, "deep")) {
 816                         thread = THREAD_DEEP;
 817                         return 0;
 818                 }
 819                 if (value && !strcasecmp(value, "shallow")) {
 820                         thread = THREAD_SHALLOW;
 821                         return 0;
 822                 }
 823                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
 824                 return 0;
 825         }
 826         if (!strcmp(var, "format.signoff")) {
 827                 do_signoff = git_config_bool(var, value);
 828                 return 0;
 829         }
 830         if (!strcmp(var, "format.signature"))
 831                 return git_config_string(&signature, var, value);
 832         if (!strcmp(var, "format.signaturefile"))
 833                 return git_config_pathname(&signature_file, var, value);
 834         if (!strcmp(var, "format.coverletter")) {
 835                 if (value && !strcasecmp(value, "auto")) {
 836                         config_cover_letter = COVER_AUTO;
 837                         return 0;
 838                 }
 839                 config_cover_letter = git_config_bool(var, value) ? COVER_ON : COVER_OFF;
 840                 return 0;
 841         }
 842         if (!strcmp(var, "format.outputdirectory"))
 843                 return git_config_string(&config_output_directory, var, value);
 844         if (!strcmp(var, "format.useautobase")) {
 845                 base_auto = git_config_bool(var, value);
 846                 return 0;
 847         }
 848         if (!strcmp(var, "format.from")) {
 849                 int b = git_parse_maybe_bool(value);
 850                 free(from);
 851                 if (b < 0)
 852                         from = xstrdup(value);
 853                 else if (b)
 854                         from = xstrdup(git_committer_info(IDENT_NO_DATE));
 855                 else
 856                         from = NULL;
 857                 return 0;
 858         }
 859
 860         return git_log_config(var, value, cb);
 861 }
 862
 863 static const char *output_directory = NULL;
 864 static int outdir_offset;
 865
 866 static int open_next_file(struct commit *commit, const char *subject,
 867                          struct rev_info *rev, int quiet)
 868 {
 869         struct strbuf filename = STRBUF_INIT;
 870         int suffix_len = strlen(rev->patch_suffix) + 1;
 871
 872         if (output_directory) {
 873                 strbuf_addstr(&filename, output_directory);
 874                 if (filename.len >=
 875                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len) {
 876                         strbuf_release(&filename);
 877                         return error(_("name of output directory is too long"));
 878                 }
 879                 strbuf_complete(&filename, '/');
 880         }
 881
 882         if (rev->numbered_files)
 883                 strbuf_addf(&filename, "%d", rev->nr);
 884         else if (commit)
 885                 fmt_output_commit(&filename, commit, rev);
 886         else
 887                 fmt_output_subject(&filename, subject, rev);
 888
 889         if (!quiet)
 890                 printf("%s\n", filename.buf + outdir_offset);
 891
 892         if ((rev->diffopt.file = fopen(filename.buf, "w")) == NULL) {
 893                 error_errno(_("Cannot open patch file %s"), filename.buf);
 894                 strbuf_release(&filename);
 895                 return -1;
 896         }
 897
 898         strbuf_release(&filename);
 899         return 0;
 900 }
 901
 902 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids)
 903 {
 904         struct rev_info check_rev;
 905         struct commit *commit, *c1, *c2;
 906         struct object *o1, *o2;
 907         unsigned flags1, flags2;
 908
 909         if (rev->pending.nr != 2)
 910                 die(_("Need exactly one range."));
 911
 912         o1 = rev->pending.objects[0].item;
 913         o2 = rev->pending.objects[1].item;
 914         flags1 = o1->flags;
 915         flags2 = o2->flags;
 916         c1 = lookup_commit_reference(the_repository, &o1->oid);
 917         c2 = lookup_commit_reference(the_repository, &o2->oid);
 918
 919         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
 920                 die(_("Not a range."));
 921
 922         init_patch_ids(the_repository, ids);
 923
 924         /* given a range a..b get all patch ids for b..a */
 925         repo_init_revisions(the_repository, &check_rev, rev->prefix);
 926         check_rev.max_parents = 1;
 927         o1->flags ^= UNINTERESTING;
 928         o2->flags ^= UNINTERESTING;
 929         add_pending_object(&check_rev, o1, "o1");
 930         add_pending_object(&check_rev, o2, "o2");
 931         if (prepare_revision_walk(&check_rev))
 932                 die(_("revision walk setup failed"));
 933
 934         while ((commit = get_revision(&check_rev)) != NULL) {
 935                 add_commit_patch_id(commit, ids);
 936         }
 937
 938         /* reset for next revision walk */
 939         clear_commit_marks(c1, SEEN | UNINTERESTING | SHOWN | ADDED);
 940         clear_commit_marks(c2, SEEN | UNINTERESTING | SHOWN | ADDED);
 941         o1->flags = flags1;
 942         o2->flags = flags2;
 943 }
 944
 945 static void gen_message_id(struct rev_info *info, char *base)
 946 {
 947         struct strbuf buf = STRBUF_INIT;
 948         strbuf_addf(&buf, "%s.%"PRItime".git.%s", base,
 949                     (timestamp_t) time(NULL),
 950                     git_committer_info(IDENT_NO_NAME|IDENT_NO_DATE|IDENT_STRICT));
 951         info->message_id = strbuf_detach(&buf, NULL);
 952 }
 953
 954 static void print_signature(FILE *file)
 955 {
 956         if (!signature || !*signature)
 957                 return;
 958
 959         fprintf(file, "-- \n%s", signature);
 960         if (signature[strlen(signature)-1] != '\n')
 961                 putc('\n', file);
 962         putc('\n', file);
 963 }
 964
 965 static void add_branch_description(struct strbuf *buf, const char *branch_name)
 966 {
 967         struct strbuf desc = STRBUF_INIT;
 968         if (!branch_name || !*branch_name)
 969                 return;
 970         read_branch_desc(&desc, branch_name);
 971         if (desc.len) {
 972                 strbuf_addch(buf, '\n');
 973                 strbuf_addbuf(buf, &desc);
 974                 strbuf_addch(buf, '\n');
 975         }
 976         strbuf_release(&desc);
 977 }
 978
 979 static char *find_branch_name(struct rev_info *rev)
 980 {
 981         int i, positive = -1;
 982         struct object_id branch_oid;
 983         const struct object_id *tip_oid;
 984         const char *ref, *v;
 985         char *full_ref, *branch = NULL;
 986
 987         for (i = 0; i < rev->cmdline.nr; i++) {
 988                 if (rev->cmdline.rev[i].flags & UNINTERESTING)
 989                         continue;
 990                 if (positive < 0)
 991                         positive = i;
 992                 else
 993                         return NULL;
 994         }
 995         if (positive < 0)
 996                 return NULL;
 997         ref = rev->cmdline.rev[positive].name;
 998         tip_oid = &rev->cmdline.rev[positive].item->oid;
 999         if (dwim_ref(ref, strlen(ref), &branch_oid, &full_ref) &&
1000             skip_prefix(full_ref, "refs/heads/", &v) &&
1001             oideq(tip_oid, &branch_oid))
1002                 branch = xstrdup(v);
1003         free(full_ref);
1004         return branch;
1005 }
1006
1007 static void show_diffstat(struct rev_info *rev,
1008                           struct commit *origin, struct commit *head)
1009 {
1010         struct diff_options opts;
1011
1012         memcpy(&opts, &rev->diffopt, sizeof(opts));
1013         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
1014         diff_setup_done(&opts);
1015
1016         diff_tree_oid(get_commit_tree_oid(origin),
1017                       get_commit_tree_oid(head),
1018                       "", &opts);
1019         diffcore_std(&opts);
1020         diff_flush(&opts);
1021
1022         fprintf(rev->diffopt.file, "\n");
1023 }
1024
1025 static void make_cover_letter(struct rev_info *rev, int use_stdout,
1026                               struct commit *origin,
1027                               int nr, struct commit **list,
1028                               const char *branch_name,
1029                               int quiet)
1030 {
1031         const char *committer;
1032         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
1033         const char *msg;
1034         struct shortlog log;
1035         struct strbuf sb = STRBUF_INIT;
1036         int i;
1037         const char *encoding = "UTF-8";
1038         int need_8bit_cte = 0;
1039         struct pretty_print_context pp = {0};
1040         struct commit *head = list[0];
1041
1042         if (!cmit_fmt_is_mail(rev->commit_format))
1043                 die(_("Cover letter needs email format"));
1044
1045         committer = git_committer_info(0);
1046
1047         if (!use_stdout &&
1048             open_next_file(NULL, rev->numbered_files ? NULL : "cover-letter", rev, quiet))
1049                 return;
1050
1051         log_write_email_headers(rev, head, &pp.after_subject, &need_8bit_cte, 0);
1052
1053         for (i = 0; !need_8bit_cte && i < nr; i++) {
1054                 const char *buf = get_commit_buffer(list[i], NULL);
1055                 if (has_non_ascii(buf))
1056                         need_8bit_cte = 1;
1057                 unuse_commit_buffer(list[i], buf);
1058         }
1059
1060         if (!branch_name)
1061                 branch_name = find_branch_name(rev);
1062
1063         msg = body;
1064         pp.fmt = CMIT_FMT_EMAIL;
1065         pp.date_mode.type = DATE_RFC2822;
1066         pp.rev = rev;
1067         pp.print_email_subject = 1;
1068         pp_user_info(&pp, NULL, &sb, committer, encoding);
1069         pp_title_line(&pp, &msg, &sb, encoding, need_8bit_cte);
1070         pp_remainder(&pp, &msg, &sb, 0);
1071         add_branch_description(&sb, branch_name);
1072         fprintf(rev->diffopt.file, "%s\n", sb.buf);
1073
1074         strbuf_release(&sb);
1075
1076         shortlog_init(&log);
1077         log.wrap_lines = 1;
1078         log.wrap = MAIL_DEFAULT_WRAP;
1079         log.in1 = 2;
1080         log.in2 = 4;
1081         log.file = rev->diffopt.file;
1082         for (i = 0; i < nr; i++)
1083                 shortlog_add_commit(&log, list[i]);
1084
1085         shortlog_output(&log);
1086
1087         /* We can only do diffstat with a unique reference point */
1088         if (origin)
1089                 show_diffstat(rev, origin, head);
1090
1091         if (rev->idiff_oid1) {
1092                 fprintf_ln(rev->diffopt.file, "%s", rev->idiff_title);
1093                 show_interdiff(rev, 0);
1094         }
1095
1096         if (rev->rdiff1) {
1097                 /*
1098                  * Pass minimum required diff-options to range-diff; others
1099                  * can be added later if deemed desirable.
1100                  */
1101                 struct diff_options opts;
1102                 diff_setup(&opts);
1103                 opts.file = rev->diffopt.file;
1104                 opts.use_color = rev->diffopt.use_color;
1105                 diff_setup_done(&opts);
1106                 fprintf_ln(rev->diffopt.file, "%s", rev->rdiff_title);
1107                 show_range_diff(rev->rdiff1, rev->rdiff2,
1108                                 rev->creation_factor, 1, &opts);
1109         }
1110 }
1111
1112 static const char *clean_message_id(const char *msg_id)
1113 {
1114         char ch;
1115         const char *a, *z, *m;
1116
1117         m = msg_id;
1118         while ((ch = *m) && (isspace(ch) || (ch == '<')))
1119                 m++;
1120         a = m;
1121         z = NULL;
1122         while ((ch = *m)) {
1123                 if (!isspace(ch) && (ch != '>'))
1124                         z = m;
1125                 m++;
1126         }
1127         if (!z)
1128                 die(_("insane in-reply-to: %s"), msg_id);
1129         if (++z == m)
1130                 return a;
1131         return xmemdupz(a, z - a);
1132 }
1133
1134 static const char *set_outdir(const char *prefix, const char *output_directory)
1135 {
1136         if (output_directory && is_absolute_path(output_directory))
1137                 return output_directory;
1138
1139         if (!prefix || !*prefix) {
1140                 if (output_directory)
1141                         return output_directory;
1142                 /* The user did not explicitly ask for "./" */
1143                 outdir_offset = 2;
1144                 return "./";
1145         }
1146
1147         outdir_offset = strlen(prefix);
1148         if (!output_directory)
1149                 return prefix;
1150
1151         return prefix_filename(prefix, output_directory);
1152 }
1153
1154 static const char * const builtin_format_patch_usage[] = {
1155         N_("git format-patch [<options>] [<since> | <revision-range>]"),
1156         NULL
1157 };
1158
1159 static int keep_subject = 0;
1160
1161 static int keep_callback(const struct option *opt, const char *arg, int unset)
1162 {
1163         BUG_ON_OPT_NEG(unset);
1164         BUG_ON_OPT_ARG(arg);
1165         ((struct rev_info *)opt->value)->total = -1;
1166         keep_subject = 1;
1167         return 0;
1168 }
1169
1170 static int subject_prefix = 0;
1171
1172 static int subject_prefix_callback(const struct option *opt, const char *arg,
1173                             int unset)
1174 {
1175         BUG_ON_OPT_NEG(unset);
1176         subject_prefix = 1;
1177         ((struct rev_info *)opt->value)->subject_prefix = arg;
1178         return 0;
1179 }
1180
1181 static int rfc_callback(const struct option *opt, const char *arg, int unset)
1182 {
1183         BUG_ON_OPT_NEG(unset);
1184         BUG_ON_OPT_ARG(arg);
1185         return subject_prefix_callback(opt, "RFC PATCH", unset);
1186 }
1187
1188 static int numbered_cmdline_opt = 0;
1189
1190 static int numbered_callback(const struct option *opt, const char *arg,
1191                              int unset)
1192 {
1193         BUG_ON_OPT_ARG(arg);
1194         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
1195         if (unset)
1196                 auto_number =  0;
1197         return 0;
1198 }
1199
1200 static int no_numbered_callback(const struct option *opt, const char *arg,
1201                                 int unset)
1202 {
1203         BUG_ON_OPT_NEG(unset);
1204         return numbered_callback(opt, arg, 1);
1205 }
1206
1207 static int output_directory_callback(const struct option *opt, const char *arg,
1208                               int unset)
1209 {
1210         const char **dir = (const char **)opt->value;
1211         BUG_ON_OPT_NEG(unset);
1212         if (*dir)
1213                 die(_("Two output directories?"));
1214         *dir = arg;
1215         return 0;
1216 }
1217
1218 static int thread_callback(const struct option *opt, const char *arg, int unset)
1219 {
1220         int *thread = (int *)opt->value;
1221         if (unset)
1222                 *thread = 0;
1223         else if (!arg || !strcmp(arg, "shallow"))
1224                 *thread = THREAD_SHALLOW;
1225         else if (!strcmp(arg, "deep"))
1226                 *thread = THREAD_DEEP;
1227         else
1228                 return 1;
1229         return 0;
1230 }
1231
1232 static int attach_callback(const struct option *opt, const char *arg, int unset)
1233 {
1234         struct rev_info *rev = (struct rev_info *)opt->value;
1235         if (unset)
1236                 rev->mime_boundary = NULL;
1237         else if (arg)
1238                 rev->mime_boundary = arg;
1239         else
1240                 rev->mime_boundary = git_version_string;
1241         rev->no_inline = unset ? 0 : 1;
1242         return 0;
1243 }
1244
1245 static int inline_callback(const struct option *opt, const char *arg, int unset)
1246 {
1247         struct rev_info *rev = (struct rev_info *)opt->value;
1248         if (unset)
1249                 rev->mime_boundary = NULL;
1250         else if (arg)
1251                 rev->mime_boundary = arg;
1252         else
1253                 rev->mime_boundary = git_version_string;
1254         rev->no_inline = 0;
1255         return 0;
1256 }
1257
1258 static int header_callback(const struct option *opt, const char *arg, int unset)
1259 {
1260         if (unset) {
1261                 string_list_clear(&extra_hdr, 0);
1262                 string_list_clear(&extra_to, 0);
1263                 string_list_clear(&extra_cc, 0);
1264         } else {
1265             add_header(arg);
1266         }
1267         return 0;
1268 }
1269
1270 static int to_callback(const struct option *opt, const char *arg, int unset)
1271 {
1272         if (unset)
1273                 string_list_clear(&extra_to, 0);
1274         else
1275                 string_list_append(&extra_to, arg);
1276         return 0;
1277 }
1278
1279 static int cc_callback(const struct option *opt, const char *arg, int unset)
1280 {
1281         if (unset)
1282                 string_list_clear(&extra_cc, 0);
1283         else
1284                 string_list_append(&extra_cc, arg);
1285         return 0;
1286 }
1287
1288 static int from_callback(const struct option *opt, const char *arg, int unset)
1289 {
1290         char **from = opt->value;
1291
1292         free(*from);
1293
1294         if (unset)
1295                 *from = NULL;
1296         else if (arg)
1297                 *from = xstrdup(arg);
1298         else
1299                 *from = xstrdup(git_committer_info(IDENT_NO_DATE));
1300         return 0;
1301 }
1302
1303 struct base_tree_info {
1304         struct object_id base_commit;
1305         int nr_patch_id, alloc_patch_id;
1306         struct object_id *patch_id;
1307 };
1308
1309 static struct commit *get_base_commit(const char *base_commit,
1310                                       struct commit **list,
1311                                       int total)
1312 {
1313         struct commit *base = NULL;
1314         struct commit **rev;
1315         int i = 0, rev_nr = 0;
1316
1317         if (base_commit && strcmp(base_commit, "auto")) {
1318                 base = lookup_commit_reference_by_name(base_commit);
1319                 if (!base)
1320                         die(_("Unknown commit %s"), base_commit);
1321         } else if ((base_commit && !strcmp(base_commit, "auto")) || base_auto) {
1322                 struct branch *curr_branch = branch_get(NULL);
1323                 const char *upstream = branch_get_upstream(curr_branch, NULL);
1324                 if (upstream) {
1325                         struct commit_list *base_list;
1326                         struct commit *commit;
1327                         struct object_id oid;
1328
1329                         if (get_oid(upstream, &oid))
1330                                 die(_("Failed to resolve '%s' as a valid ref."), upstream);
1331                         commit = lookup_commit_or_die(&oid, "upstream base");
1332                         base_list = get_merge_bases_many(commit, total, list);
1333                         /* There should be one and only one merge base. */
1334                         if (!base_list || base_list->next)
1335                                 die(_("Could not find exact merge base."));
1336                         base = base_list->item;
1337                         free_commit_list(base_list);
1338                 } else {
1339                         die(_("Failed to get upstream, if you want to record base commit automatically,\n"
1340                               "please use git branch --set-upstream-to to track a remote branch.\n"
1341                               "Or you could specify base commit by --base=<base-commit-id> manually."));
1342                 }
1343         }
1344
1345         ALLOC_ARRAY(rev, total);
1346         for (i = 0; i < total; i++)
1347                 rev[i] = list[i];
1348
1349         rev_nr = total;
1350         /*
1351          * Get merge base through pair-wise computations
1352          * and store it in rev[0].
1353          */
1354         while (rev_nr > 1) {
1355                 for (i = 0; i < rev_nr / 2; i++) {
1356                         struct commit_list *merge_base;
1357                         merge_base = get_merge_bases(rev[2 * i], rev[2 * i + 1]);
1358                         if (!merge_base || merge_base->next)
1359                                 die(_("Failed to find exact merge base"));
1360
1361                         rev[i] = merge_base->item;
1362                 }
1363
1364                 if (rev_nr % 2)
1365                         rev[i] = rev[2 * i];
1366                 rev_nr = DIV_ROUND_UP(rev_nr, 2);
1367         }
1368
1369         if (!in_merge_bases(base, rev[0]))
1370                 die(_("base commit should be the ancestor of revision list"));
1371
1372         for (i = 0; i < total; i++) {
1373                 if (base == list[i])
1374                         die(_("base commit shouldn't be in revision list"));
1375         }
1376
1377         free(rev);
1378         return base;
1379 }
1380
1381 define_commit_slab(commit_base, int);
1382
1383 static void prepare_bases(struct base_tree_info *bases,
1384                           struct commit *base,
1385                           struct commit **list,
1386                           int total)
1387 {
1388         struct commit *commit;
1389         struct rev_info revs;
1390         struct diff_options diffopt;
1391         struct commit_base commit_base;
1392         int i;
1393
1394         if (!base)
1395                 return;
1396
1397         init_commit_base(&commit_base);
1398         repo_diff_setup(the_repository, &diffopt);
1399         diffopt.flags.recursive = 1;
1400         diff_setup_done(&diffopt);
1401
1402         oidcpy(&bases->base_commit, &base->object.oid);
1403
1404         repo_init_revisions(the_repository, &revs, NULL);
1405         revs.max_parents = 1;
1406         revs.topo_order = 1;
1407         for (i = 0; i < total; i++) {
1408                 list[i]->object.flags &= ~UNINTERESTING;
1409                 add_pending_object(&revs, &list[i]->object, "rev_list");
1410                 *commit_base_at(&commit_base, list[i]) = 1;
1411         }
1412         base->object.flags |= UNINTERESTING;
1413         add_pending_object(&revs, &base->object, "base");
1414
1415         if (prepare_revision_walk(&revs))
1416                 die(_("revision walk setup failed"));
1417         /*
1418          * Traverse the commits list, get prerequisite patch ids
1419          * and stuff them in bases structure.
1420          */
1421         while ((commit = get_revision(&revs)) != NULL) {
1422                 struct object_id oid;
1423                 struct object_id *patch_id;
1424                 if (*commit_base_at(&commit_base, commit))
1425                         continue;
1426                 if (commit_patch_id(commit, &diffopt, &oid, 0))
1427                         die(_("cannot get patch id"));
1428                 ALLOC_GROW(bases->patch_id, bases->nr_patch_id + 1, bases->alloc_patch_id);
1429                 patch_id = bases->patch_id + bases->nr_patch_id;
1430                 oidcpy(patch_id, &oid);
1431                 bases->nr_patch_id++;
1432         }
1433         clear_commit_base(&commit_base);
1434 }
1435
1436 static void print_bases(struct base_tree_info *bases, FILE *file)
1437 {
1438         int i;
1439
1440         /* Only do this once, either for the cover or for the first one */
1441         if (is_null_oid(&bases->base_commit))
1442                 return;
1443
1444         /* Show the base commit */
1445         fprintf(file, "\nbase-commit: %s\n", oid_to_hex(&bases->base_commit));
1446
1447         /* Show the prerequisite patches */
1448         for (i = bases->nr_patch_id - 1; i >= 0; i--)
1449                 fprintf(file, "prerequisite-patch-id: %s\n", oid_to_hex(&bases->patch_id[i]));
1450
1451         free(bases->patch_id);
1452         bases->nr_patch_id = 0;
1453         bases->alloc_patch_id = 0;
1454         oidclr(&bases->base_commit);
1455 }
1456
1457 static const char *diff_title(struct strbuf *sb, int reroll_count,
1458                        const char *generic, const char *rerolled)
1459 {
1460         if (reroll_count <= 0)
1461                 strbuf_addstr(sb, generic);
1462         else /* RFC may be v0, so allow -v1 to diff against v0 */
1463                 strbuf_addf(sb, rerolled, reroll_count - 1);
1464         return sb->buf;
1465 }
1466
1467 static void infer_range_diff_ranges(struct strbuf *r1,
1468                                     struct strbuf *r2,
1469                                     const char *prev,
1470                                     struct commit *origin,
1471                                     struct commit *head)
1472 {
1473         const char *head_oid = oid_to_hex(&head->object.oid);
1474
1475         if (!strstr(prev, "..")) {
1476                 strbuf_addf(r1, "%s..%s", head_oid, prev);
1477                 strbuf_addf(r2, "%s..%s", prev, head_oid);
1478         } else if (!origin) {
1479                 die(_("failed to infer range-diff ranges"));
1480         } else {
1481                 strbuf_addstr(r1, prev);
1482                 strbuf_addf(r2, "%s..%s",
1483                             oid_to_hex(&origin->object.oid), head_oid);
1484         }
1485 }
1486
1487 int cmd_format_patch(int argc, const char **argv, const char *prefix)
1488 {
1489         struct commit *commit;
1490         struct commit **list = NULL;
1491         struct rev_info rev;
1492         struct setup_revision_opt s_r_opt;
1493         int nr = 0, total, i;
1494         int use_stdout = 0;
1495         int start_number = -1;
1496         int just_numbers = 0;
1497         int ignore_if_in_upstream = 0;
1498         int cover_letter = -1;
1499         int boundary_count = 0;
1500         int no_binary_diff = 0;
1501         int zero_commit = 0;
1502         struct commit *origin = NULL;
1503         const char *in_reply_to = NULL;
1504         struct patch_ids ids;
1505         struct strbuf buf = STRBUF_INIT;
1506         int use_patch_format = 0;
1507         int quiet = 0;
1508         int reroll_count = -1;
1509         char *branch_name = NULL;
1510         char *base_commit = NULL;
1511         struct base_tree_info bases;
1512         int show_progress = 0;
1513         struct progress *progress = NULL;
1514         struct oid_array idiff_prev = OID_ARRAY_INIT;
1515         struct strbuf idiff_title = STRBUF_INIT;
1516         const char *rdiff_prev = NULL;
1517         struct strbuf rdiff1 = STRBUF_INIT;
1518         struct strbuf rdiff2 = STRBUF_INIT;
1519         struct strbuf rdiff_title = STRBUF_INIT;
1520         int creation_factor = -1;
1521
1522         const struct option builtin_format_patch_options[] = {
1523                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
1524                             N_("use [PATCH n/m] even with a single patch"),
1525                             PARSE_OPT_NOARG, numbered_callback },
1526                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
1527                             N_("use [PATCH] even with multiple patches"),
1528                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, no_numbered_callback },
1529                 OPT_BOOL('s', "signoff", &do_signoff, N_("add Signed-off-by:")),
1530                 OPT_BOOL(0, "stdout", &use_stdout,
1531                             N_("print patches to standard out")),
1532                 OPT_BOOL(0, "cover-letter", &cover_letter,
1533                             N_("generate a cover letter")),
1534                 OPT_BOOL(0, "numbered-files", &just_numbers,
1535                             N_("use simple number sequence for output file names")),
1536                 OPT_STRING(0, "suffix", &fmt_patch_suffix, N_("sfx"),
1537                             N_("use <sfx> instead of '.patch'")),
1538                 OPT_INTEGER(0, "start-number", &start_number,
1539                             N_("start numbering patches at <n> instead of 1")),
1540                 OPT_INTEGER('v', "reroll-count", &reroll_count,
1541                             N_("mark the series as Nth re-roll")),
1542                 { OPTION_CALLBACK, 0, "rfc", &rev, NULL,
1543                             N_("Use [RFC PATCH] instead of [PATCH]"),
1544                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, rfc_callback },
1545                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, N_("prefix"),
1546                             N_("Use [<prefix>] instead of [PATCH]"),
1547                             PARSE_OPT_NONEG, subject_prefix_callback },
1548                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
1549                             N_("dir"), N_("store resulting files in <dir>"),
1550                             PARSE_OPT_NONEG, output_directory_callback },
1551                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
1552                             N_("don't strip/add [PATCH]"),
1553                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
1554                 OPT_BOOL(0, "no-binary", &no_binary_diff,
1555                          N_("don't output binary diffs")),
1556                 OPT_BOOL(0, "zero-commit", &zero_commit,
1557                          N_("output all-zero hash in From header")),
1558                 OPT_BOOL(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
1559                          N_("don't include a patch matching a commit upstream")),
1560                 OPT_SET_INT_F('p', "no-stat", &use_patch_format,
1561                               N_("show patch format instead of default (patch + stat)"),
1562                               1, PARSE_OPT_NONEG),
1563                 OPT_GROUP(N_("Messaging")),
1564                 { OPTION_CALLBACK, 0, "add-header", NULL, N_("header"),
1565                             N_("add email header"), 0, header_callback },
1566                 { OPTION_CALLBACK, 0, "to", NULL, N_("email"), N_("add To: header"),
1567                             0, to_callback },
1568                 { OPTION_CALLBACK, 0, "cc", NULL, N_("email"), N_("add Cc: header"),
1569                             0, cc_callback },
1570                 { OPTION_CALLBACK, 0, "from", &from, N_("ident"),
1571                             N_("set From address to <ident> (or committer ident if absent)"),
1572                             PARSE_OPT_OPTARG, from_callback },
1573                 OPT_STRING(0, "in-reply-to", &in_reply_to, N_("message-id"),
1574                             N_("make first mail a reply to <message-id>")),
1575                 { OPTION_CALLBACK, 0, "attach", &rev, N_("boundary"),
1576                             N_("attach the patch"), PARSE_OPT_OPTARG,
1577                             attach_callback },
1578                 { OPTION_CALLBACK, 0, "inline", &rev, N_("boundary"),
1579                             N_("inline the patch"),
1580                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
1581                             inline_callback },
1582                 { OPTION_CALLBACK, 0, "thread", &thread, N_("style"),
1583                             N_("enable message threading, styles: shallow, deep"),
1584                             PARSE_OPT_OPTARG, thread_callback },
1585                 OPT_STRING(0, "signature", &signature, N_("signature"),
1586                             N_("add a signature")),
1587                 OPT_STRING(0, "base", &base_commit, N_("base-commit"),
1588                            N_("add prerequisite tree info to the patch series")),
1589                 OPT_FILENAME(0, "signature-file", &signature_file,
1590                                 N_("add a signature from a file")),
1591                 OPT__QUIET(&quiet, N_("don't print the patch filenames")),
1592                 OPT_BOOL(0, "progress", &show_progress,
1593                          N_("show progress while generating patches")),
1594                 OPT_CALLBACK(0, "interdiff", &idiff_prev, N_("rev"),
1595                              N_("show changes against <rev> in cover letter or single patch"),
1596                              parse_opt_object_name),
1597                 OPT_STRING(0, "range-diff", &rdiff_prev, N_("refspec"),
1598                            N_("show changes against <refspec> in cover letter or single patch")),
1599                 OPT_INTEGER(0, "creation-factor", &creation_factor,
1600                             N_("percentage by which creation is weighted")),
1601                 OPT_END()
1602         };
1603
1604         extra_hdr.strdup_strings = 1;
1605         extra_to.strdup_strings = 1;
1606         extra_cc.strdup_strings = 1;
1607         init_log_defaults();
1608         git_config(git_format_config, NULL);
1609         repo_init_revisions(the_repository, &rev, prefix);
1610         rev.commit_format = CMIT_FMT_EMAIL;
1611         rev.expand_tabs_in_log_default = 0;
1612         rev.verbose_header = 1;
1613         rev.diff = 1;
1614         rev.max_parents = 1;
1615         rev.diffopt.flags.recursive = 1;
1616         rev.subject_prefix = fmt_patch_subject_prefix;
1617         memset(&s_r_opt, 0, sizeof(s_r_opt));
1618         s_r_opt.def = "HEAD";
1619         s_r_opt.revarg_opt = REVARG_COMMITTISH;
1620
1621         if (default_attach) {
1622                 rev.mime_boundary = default_attach;
1623                 rev.no_inline = 1;
1624         }
1625
1626         /*
1627          * Parse the arguments before setup_revisions(), or something
1628          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1629          * possibly a valid SHA1.
1630          */
1631         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1632                              builtin_format_patch_usage,
1633                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1634                              PARSE_OPT_KEEP_DASHDASH);
1635
1636         if (0 < reroll_count) {
1637                 struct strbuf sprefix = STRBUF_INIT;
1638                 strbuf_addf(&sprefix, "%s v%d",
1639                             rev.subject_prefix, reroll_count);
1640                 rev.reroll_count = reroll_count;
1641                 rev.subject_prefix = strbuf_detach(&sprefix, NULL);
1642         }
1643
1644         for (i = 0; i < extra_hdr.nr; i++) {
1645                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1646                 strbuf_addch(&buf, '\n');
1647         }
1648
1649         if (extra_to.nr)
1650                 strbuf_addstr(&buf, "To: ");
1651         for (i = 0; i < extra_to.nr; i++) {
1652                 if (i)
1653                         strbuf_addstr(&buf, "    ");
1654                 strbuf_addstr(&buf, extra_to.items[i].string);
1655                 if (i + 1 < extra_to.nr)
1656                         strbuf_addch(&buf, ',');
1657                 strbuf_addch(&buf, '\n');
1658         }
1659
1660         if (extra_cc.nr)
1661                 strbuf_addstr(&buf, "Cc: ");
1662         for (i = 0; i < extra_cc.nr; i++) {
1663                 if (i)
1664                         strbuf_addstr(&buf, "    ");
1665                 strbuf_addstr(&buf, extra_cc.items[i].string);
1666                 if (i + 1 < extra_cc.nr)
1667                         strbuf_addch(&buf, ',');
1668                 strbuf_addch(&buf, '\n');
1669         }
1670
1671         rev.extra_headers = strbuf_detach(&buf, NULL);
1672
1673         if (from) {
1674                 if (split_ident_line(&rev.from_ident, from, strlen(from)))
1675                         die(_("invalid ident line: %s"), from);
1676         }
1677
1678         if (start_number < 0)
1679                 start_number = 1;
1680
1681         /*
1682          * If numbered is set solely due to format.numbered in config,
1683          * and it would conflict with --keep-subject (-k) from the
1684          * command line, reset "numbered".
1685          */
1686         if (numbered && keep_subject && !numbered_cmdline_opt)
1687                 numbered = 0;
1688
1689         if (numbered && keep_subject)
1690                 die(_("-n and -k are mutually exclusive"));
1691         if (keep_subject && subject_prefix)
1692                 die(_("--subject-prefix/--rfc and -k are mutually exclusive"));
1693         rev.preserve_subject = keep_subject;
1694
1695         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1696         if (argc > 1)
1697                 die(_("unrecognized argument: %s"), argv[1]);
1698
1699         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1700                 die(_("--name-only does not make sense"));
1701         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1702                 die(_("--name-status does not make sense"));
1703         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1704                 die(_("--check does not make sense"));
1705
1706         if (!use_patch_format &&
1707                 (!rev.diffopt.output_format ||
1708                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1709                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1710         if (!rev.diffopt.stat_width)
1711                 rev.diffopt.stat_width = MAIL_DEFAULT_WRAP;
1712
1713         /* Always generate a patch */
1714         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1715
1716         rev.zero_commit = zero_commit;
1717
1718         if (!rev.diffopt.flags.text && !no_binary_diff)
1719                 rev.diffopt.flags.binary = 1;
1720
1721         if (rev.show_notes)
1722                 init_display_notes(&rev.notes_opt);
1723
1724         if (!output_directory && !use_stdout)
1725                 output_directory = config_output_directory;
1726
1727         if (!use_stdout)
1728                 output_directory = set_outdir(prefix, output_directory);
1729         else
1730                 setup_pager();
1731
1732         if (output_directory) {
1733                 if (rev.diffopt.use_color != GIT_COLOR_ALWAYS)
1734                         rev.diffopt.use_color = GIT_COLOR_NEVER;
1735                 if (use_stdout)
1736                         die(_("standard output, or directory, which one?"));
1737                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1738                         die_errno(_("Could not create directory '%s'"),
1739                                   output_directory);
1740         }
1741
1742         if (rev.pending.nr == 1) {
1743                 int check_head = 0;
1744
1745                 if (rev.max_count < 0 && !rev.show_root_diff) {
1746                         /*
1747                          * This is traditional behaviour of "git format-patch
1748                          * origin" that prepares what the origin side still
1749                          * does not have.
1750                          */
1751                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1752                         add_head_to_pending(&rev);
1753                         check_head = 1;
1754                 }
1755                 /*
1756                  * Otherwise, it is "format-patch -22 HEAD", and/or
1757                  * "format-patch --root HEAD".  The user wants
1758                  * get_revision() to do the usual traversal.
1759                  */
1760
1761                 if (!strcmp(rev.pending.objects[0].name, "HEAD"))
1762                         check_head = 1;
1763
1764                 if (check_head) {
1765                         const char *ref, *v;
1766                         ref = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,
1767                                                  NULL, NULL);
1768                         if (ref && skip_prefix(ref, "refs/heads/", &v))
1769                                 branch_name = xstrdup(v);
1770                         else
1771                                 branch_name = xstrdup(""); /* no branch */
1772                 }
1773         }
1774
1775         /*
1776          * We cannot move this anywhere earlier because we do want to
1777          * know if --root was given explicitly from the command line.
1778          */
1779         rev.show_root_diff = 1;
1780
1781         if (ignore_if_in_upstream) {
1782                 /* Don't say anything if head and upstream are the same. */
1783                 if (rev.pending.nr == 2) {
1784                         struct object_array_entry *o = rev.pending.objects;
1785                         if (oideq(&o[0].item->oid, &o[1].item->oid))
1786                                 goto done;
1787                 }
1788                 get_patch_ids(&rev, &ids);
1789         }
1790
1791         if (prepare_revision_walk(&rev))
1792                 die(_("revision walk setup failed"));
1793         rev.boundary = 1;
1794         while ((commit = get_revision(&rev)) != NULL) {
1795                 if (commit->object.flags & BOUNDARY) {
1796                         boundary_count++;
1797                         origin = (boundary_count == 1) ? commit : NULL;
1798                         continue;
1799                 }
1800
1801                 if (ignore_if_in_upstream && has_commit_patch_id(commit, &ids))
1802                         continue;
1803
1804                 nr++;
1805                 REALLOC_ARRAY(list, nr);
1806                 list[nr - 1] = commit;
1807         }
1808         if (nr == 0)
1809                 /* nothing to do */
1810                 goto done;
1811         total = nr;
1812         if (cover_letter == -1) {
1813                 if (config_cover_letter == COVER_AUTO)
1814                         cover_letter = (total > 1);
1815                 else
1816                         cover_letter = (config_cover_letter == COVER_ON);
1817         }
1818         if (!keep_subject && auto_number && (total > 1 || cover_letter))
1819                 numbered = 1;
1820         if (numbered)
1821                 rev.total = total + start_number - 1;
1822
1823         if (idiff_prev.nr) {
1824                 if (!cover_letter && total != 1)
1825                         die(_("--interdiff requires --cover-letter or single patch"));
1826                 rev.idiff_oid1 = &idiff_prev.oid[idiff_prev.nr - 1];
1827                 rev.idiff_oid2 = get_commit_tree_oid(list[0]);
1828                 rev.idiff_title = diff_title(&idiff_title, reroll_count,
1829                                              _("Interdiff:"),
1830                                              _("Interdiff against v%d:"));
1831         }
1832
1833         if (creation_factor < 0)
1834                 creation_factor = RANGE_DIFF_CREATION_FACTOR_DEFAULT;
1835         else if (!rdiff_prev)
1836                 die(_("--creation-factor requires --range-diff"));
1837
1838         if (rdiff_prev) {
1839                 if (!cover_letter && total != 1)
1840                         die(_("--range-diff requires --cover-letter or single patch"));
1841
1842                 infer_range_diff_ranges(&rdiff1, &rdiff2, rdiff_prev,
1843                                         origin, list[0]);
1844                 rev.rdiff1 = rdiff1.buf;
1845                 rev.rdiff2 = rdiff2.buf;
1846                 rev.creation_factor = creation_factor;
1847                 rev.rdiff_title = diff_title(&rdiff_title, reroll_count,
1848                                              _("Range-diff:"),
1849                                              _("Range-diff against v%d:"));
1850         }
1851
1852         if (!signature) {
1853                 ; /* --no-signature inhibits all signatures */
1854         } else if (signature && signature != git_version_string) {
1855                 ; /* non-default signature already set */
1856         } else if (signature_file) {
1857                 struct strbuf buf = STRBUF_INIT;
1858
1859                 if (strbuf_read_file(&buf, signature_file, 128) < 0)
1860                         die_errno(_("unable to read signature file '%s'"), signature_file);
1861                 signature = strbuf_detach(&buf, NULL);
1862         }
1863
1864         memset(&bases, 0, sizeof(bases));
1865         if (base_commit || base_auto) {
1866                 struct commit *base = get_base_commit(base_commit, list, nr);
1867                 reset_revision_walk();
1868                 clear_object_flags(UNINTERESTING);
1869                 prepare_bases(&bases, base, list, nr);
1870         }
1871
1872         if (in_reply_to || thread || cover_letter)
1873                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1874         if (in_reply_to) {
1875                 const char *msgid = clean_message_id(in_reply_to);
1876                 string_list_append(rev.ref_message_ids, msgid);
1877         }
1878         rev.numbered_files = just_numbers;
1879         rev.patch_suffix = fmt_patch_suffix;
1880         if (cover_letter) {
1881                 if (thread)
1882                         gen_message_id(&rev, "cover");
1883                 make_cover_letter(&rev, use_stdout,
1884                                   origin, nr, list, branch_name, quiet);
1885                 print_bases(&bases, rev.diffopt.file);
1886                 print_signature(rev.diffopt.file);
1887                 total++;
1888                 start_number--;
1889                 /* interdiff/range-diff in cover-letter; omit from patches */
1890                 rev.idiff_oid1 = NULL;
1891                 rev.rdiff1 = NULL;
1892         }
1893         rev.add_signoff = do_signoff;
1894
1895         if (show_progress)
1896                 progress = start_delayed_progress(_("Generating patches"), total);
1897         while (0 <= --nr) {
1898                 int shown;
1899                 display_progress(progress, total - nr);
1900                 commit = list[nr];
1901                 rev.nr = total - nr + (start_number - 1);
1902                 /* Make the second and subsequent mails replies to the first */
1903                 if (thread) {
1904                         /* Have we already had a message ID? */
1905                         if (rev.message_id) {
1906                                 /*
1907                                  * For deep threading: make every mail
1908                                  * a reply to the previous one, no
1909                                  * matter what other options are set.
1910                                  *
1911                                  * For shallow threading:
1912                                  *
1913                                  * Without --cover-letter and
1914                                  * --in-reply-to, make every mail a
1915                                  * reply to the one before.
1916                                  *
1917                                  * With --in-reply-to but no
1918                                  * --cover-letter, make every mail a
1919                                  * reply to the <reply-to>.
1920                                  *
1921                                  * With --cover-letter, make every
1922                                  * mail but the cover letter a reply
1923                                  * to the cover letter.  The cover
1924                                  * letter is a reply to the
1925                                  * --in-reply-to, if specified.
1926                                  */
1927                                 if (thread == THREAD_SHALLOW
1928                                     && rev.ref_message_ids->nr > 0
1929                                     && (!cover_letter || rev.nr > 1))
1930                                         free(rev.message_id);
1931                                 else
1932                                         string_list_append(rev.ref_message_ids,
1933                                                            rev.message_id);
1934                         }
1935                         gen_message_id(&rev, oid_to_hex(&commit->object.oid));
1936                 }
1937
1938                 if (!use_stdout &&
1939                     open_next_file(rev.numbered_files ? NULL : commit, NULL, &rev, quiet))
1940                         die(_("Failed to create output files"));
1941                 shown = log_tree_commit(&rev, commit);
1942                 free_commit_buffer(commit);
1943
1944                 /* We put one extra blank line between formatted
1945                  * patches and this flag is used by log-tree code
1946                  * to see if it needs to emit a LF before showing
1947                  * the log; when using one file per patch, we do
1948                  * not want the extra blank line.
1949                  */
1950                 if (!use_stdout)
1951                         rev.shown_one = 0;
1952                 if (shown) {
1953                         print_bases(&bases, rev.diffopt.file);
1954                         if (rev.mime_boundary)
1955                                 fprintf(rev.diffopt.file, "\n--%s%s--\n\n\n",
1956                                        mime_boundary_leader,
1957                                        rev.mime_boundary);
1958                         else
1959                                 print_signature(rev.diffopt.file);
1960                 }
1961                 if (!use_stdout)
1962                         fclose(rev.diffopt.file);
1963         }
1964         stop_progress(&progress);
1965         free(list);
1966         free(branch_name);
1967         string_list_clear(&extra_to, 0);
1968         string_list_clear(&extra_cc, 0);
1969         string_list_clear(&extra_hdr, 0);
1970         if (ignore_if_in_upstream)
1971                 free_patch_ids(&ids);
1972
1973 done:
1974         oid_array_clear(&idiff_prev);
1975         strbuf_release(&idiff_title);
1976         strbuf_release(&rdiff1);
1977         strbuf_release(&rdiff2);
1978         strbuf_release(&rdiff_title);
1979         return 0;
1980 }
1981
1982 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1983 {
1984         struct object_id oid;
1985         if (get_oid(arg, &oid) == 0) {
1986                 struct commit *commit = lookup_commit_reference(the_repository,
1987                                                                 &oid);
1988                 if (commit) {
1989                         commit->object.flags |= flags;
1990                         add_pending_object(revs, &commit->object, arg);
1991                         return 0;
1992                 }
1993         }
1994         return -1;
1995 }
1996
1997 static const char * const cherry_usage[] = {
1998         N_("git cherry [-v] [<upstream> [<head> [<limit>]]]"),
1999         NULL
2000 };
2001
2002 static void print_commit(char sign, struct commit *commit, int verbose,
2003                          int abbrev, FILE *file)
2004 {
2005         if (!verbose) {
2006                 fprintf(file, "%c %s\n", sign,
2007                        find_unique_abbrev(&commit->object.oid, abbrev));
2008         } else {
2009                 struct strbuf buf = STRBUF_INIT;
2010                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
2011                 fprintf(file, "%c %s %s\n", sign,
2012                        find_unique_abbrev(&commit->object.oid, abbrev),
2013                        buf.buf);
2014                 strbuf_release(&buf);
2015         }
2016 }
2017
2018 int cmd_cherry(int argc, const char **argv, const char *prefix)
2019 {
2020         struct rev_info revs;
2021         struct patch_ids ids;
2022         struct commit *commit;
2023         struct commit_list *list = NULL;
2024         struct branch *current_branch;
2025         const char *upstream;
2026         const char *head = "HEAD";
2027         const char *limit = NULL;
2028         int verbose = 0, abbrev = 0;
2029
2030         struct option options[] = {
2031                 OPT__ABBREV(&abbrev),
2032                 OPT__VERBOSE(&verbose, N_("be verbose")),
2033                 OPT_END()
2034         };
2035
2036         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
2037
2038         switch (argc) {
2039         case 3:
2040                 limit = argv[2];
2041                 /* FALLTHROUGH */
2042         case 2:
2043                 head = argv[1];
2044                 /* FALLTHROUGH */
2045         case 1:
2046                 upstream = argv[0];
2047                 break;
2048         default:
2049                 current_branch = branch_get(NULL);
2050                 upstream = branch_get_upstream(current_branch, NULL);
2051                 if (!upstream) {
2052                         fprintf(stderr, _("Could not find a tracked"
2053                                         " remote branch, please"
2054                                         " specify <upstream> manually.\n"));
2055                         usage_with_options(cherry_usage, options);
2056                 }
2057         }
2058
2059         repo_init_revisions(the_repository, &revs, prefix);
2060         revs.max_parents = 1;
2061
2062         if (add_pending_commit(head, &revs, 0))
2063                 die(_("Unknown commit %s"), head);
2064         if (add_pending_commit(upstream, &revs, UNINTERESTING))
2065                 die(_("Unknown commit %s"), upstream);
2066
2067         /* Don't say anything if head and upstream are the same. */
2068         if (revs.pending.nr == 2) {
2069                 struct object_array_entry *o = revs.pending.objects;
2070                 if (oideq(&o[0].item->oid, &o[1].item->oid))
2071                         return 0;
2072         }
2073
2074         get_patch_ids(&revs, &ids);
2075
2076         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
2077                 die(_("Unknown commit %s"), limit);
2078
2079         /* reverse the list of commits */
2080         if (prepare_revision_walk(&revs))
2081                 die(_("revision walk setup failed"));
2082         while ((commit = get_revision(&revs)) != NULL) {
2083                 commit_list_insert(commit, &list);
2084         }
2085
2086         while (list) {
2087                 char sign = '+';
2088
2089                 commit = list->item;
2090                 if (has_commit_patch_id(commit, &ids))
2091                         sign = '-';
2092                 print_commit(sign, commit, verbose, abbrev, revs.diffopt.file);
2093                 list = list->next;
2094         }
2095
2096         free_patch_ids(&ids);
2097         return 0;
2098 }