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 "commit.h"
   9 #include "diff.h"
  10 #include "revision.h"
  11 #include "log-tree.h"
  12 #include "builtin.h"
  13 #include "tag.h"
  14 #include "reflog-walk.h"
  15 #include "patch-ids.h"
  16 #include "refs.h"
  17
  18 static int default_show_root = 1;
  19 static const char *fmt_patch_subject_prefix = "PATCH";
  20
  21 /* this is in builtin-diff.c */
  22 void add_head(struct rev_info *revs);
  23
  24 static void add_name_decoration(const char *prefix, const char *name, struct object *obj)
  25 {
  26         int plen = strlen(prefix);
  27         int nlen = strlen(name);
  28         struct name_decoration *res = xmalloc(sizeof(struct name_decoration) + plen + nlen);
  29         memcpy(res->name, prefix, plen);
  30         memcpy(res->name + plen, name, nlen + 1);
  31         res->next = add_decoration(&name_decoration, obj, res);
  32 }
  33
  34 static int add_ref_decoration(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
  35 {
  36         struct object *obj = parse_object(sha1);
  37         if (!obj)
  38                 return 0;
  39         add_name_decoration("", refname, obj);
  40         while (obj->type == OBJ_TAG) {
  41                 obj = ((struct tag *)obj)->tagged;
  42                 if (!obj)
  43                         break;
  44                 add_name_decoration("tag: ", refname, obj);
  45         }
  46         return 0;
  47 }
  48
  49 static void cmd_log_init(int argc, const char **argv, const char *prefix,
  50                       struct rev_info *rev)
  51 {
  52         int i;
  53         int decorate = 0;
  54
  55         rev->abbrev = DEFAULT_ABBREV;
  56         rev->commit_format = CMIT_FMT_DEFAULT;
  57         rev->verbose_header = 1;
  58         rev->diffopt.recursive = 1;
  59         rev->show_root_diff = default_show_root;
  60         rev->subject_prefix = fmt_patch_subject_prefix;
  61         argc = setup_revisions(argc, argv, rev, "HEAD");
  62         if (rev->diffopt.pickaxe || rev->diffopt.filter)
  63                 rev->always_show_header = 0;
  64         if (rev->diffopt.follow_renames) {
  65                 rev->always_show_header = 0;
  66                 if (rev->diffopt.nr_paths != 1)
  67                         usage("git logs can only follow renames on one pathname at a time");
  68         }
  69         for (i = 1; i < argc; i++) {
  70                 const char *arg = argv[i];
  71                 if (!strcmp(arg, "--decorate")) {
  72                         if (!decorate)
  73                                 for_each_ref(add_ref_decoration, NULL);
  74                         decorate = 1;
  75                 } else
  76                         die("unrecognized argument: %s", arg);
  77         }
  78 }
  79
  80 /*
  81  * This gives a rough estimate for how many commits we
  82  * will print out in the list.
  83  */
  84 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
  85 {
  86         int n = 0;
  87
  88         while (list) {
  89                 struct commit *commit = list->item;
  90                 unsigned int flags = commit->object.flags;
  91                 list = list->next;
  92                 if (!(flags & (TREESAME | UNINTERESTING)))
  93                         n++;
  94         }
  95         return n;
  96 }
  97
  98 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
  99 {
 100         if (rev->shown_one) {
 101                 rev->shown_one = 0;
 102                 if (rev->commit_format != CMIT_FMT_ONELINE)
 103                         putchar(rev->diffopt.line_termination);
 104         }
 105         printf("Final output: %d %s\n", nr, stage);
 106 }
 107
 108 struct itimerval early_output_timer;
 109
 110 static void log_show_early(struct rev_info *revs, struct commit_list *list)
 111 {
 112         int i = revs->early_output;
 113         int show_header = 1;
 114
 115         sort_in_topological_order(&list, revs->lifo);
 116         while (list && i) {
 117                 struct commit *commit = list->item;
 118                 switch (simplify_commit(revs, commit)) {
 119                 case commit_show:
 120                         if (show_header) {
 121                                 int n = estimate_commit_count(revs, list);
 122                                 show_early_header(revs, "incomplete", n);
 123                                 show_header = 0;
 124                         }
 125                         log_tree_commit(revs, commit);
 126                         i--;
 127                         break;
 128                 case commit_ignore:
 129                         break;
 130                 case commit_error:
 131                         return;
 132                 }
 133                 list = list->next;
 134         }
 135
 136         /* Did we already get enough commits for the early output? */
 137         if (!i)
 138                 return;
 139
 140         /*
 141          * ..if no, then repeat it twice a second until we
 142          * do.
 143          *
 144          * NOTE! We don't use "it_interval", because if the
 145          * reader isn't listening, we want our output to be
 146          * throttled by the writing, and not have the timer
 147          * trigger every second even if we're blocked on a
 148          * reader!
 149          */
 150         early_output_timer.it_value.tv_sec = 0;
 151         early_output_timer.it_value.tv_usec = 500000;
 152         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 153 }
 154
 155 static void early_output(int signal)
 156 {
 157         show_early_output = log_show_early;
 158 }
 159
 160 static void setup_early_output(struct rev_info *rev)
 161 {
 162         struct sigaction sa;
 163
 164         /*
 165          * Set up the signal handler, minimally intrusively:
 166          * we only set a single volatile integer word (not
 167          * using sigatomic_t - trying to avoid unnecessary
 168          * system dependencies and headers), and using
 169          * SA_RESTART.
 170          */
 171         memset(&sa, 0, sizeof(sa));
 172         sa.sa_handler = early_output;
 173         sigemptyset(&sa.sa_mask);
 174         sa.sa_flags = SA_RESTART;
 175         sigaction(SIGALRM, &sa, NULL);
 176
 177         /*
 178          * If we can get the whole output in less than a
 179          * tenth of a second, don't even bother doing the
 180          * early-output thing..
 181          *
 182          * This is a one-time-only trigger.
 183          */
 184         early_output_timer.it_value.tv_sec = 0;
 185         early_output_timer.it_value.tv_usec = 100000;
 186         setitimer(ITIMER_REAL, &early_output_timer, NULL);
 187 }
 188
 189 static void finish_early_output(struct rev_info *rev)
 190 {
 191         int n = estimate_commit_count(rev, rev->commits);
 192         signal(SIGALRM, SIG_IGN);
 193         show_early_header(rev, "done", n);
 194 }
 195
 196 static int cmd_log_walk(struct rev_info *rev)
 197 {
 198         struct commit *commit;
 199
 200         if (rev->early_output)
 201                 setup_early_output(rev);
 202
 203         prepare_revision_walk(rev);
 204
 205         if (rev->early_output)
 206                 finish_early_output(rev);
 207
 208         while ((commit = get_revision(rev)) != NULL) {
 209                 log_tree_commit(rev, commit);
 210                 if (!rev->reflog_info) {
 211                         /* we allow cycles in reflog ancestry */
 212                         free(commit->buffer);
 213                         commit->buffer = NULL;
 214                 }
 215                 free_commit_list(commit->parents);
 216                 commit->parents = NULL;
 217         }
 218         return 0;
 219 }
 220
 221 static int git_log_config(const char *var, const char *value)
 222 {
 223         if (!strcmp(var, "format.subjectprefix")) {
 224                 if (!value)
 225                         die("format.subjectprefix without value");
 226                 fmt_patch_subject_prefix = xstrdup(value);
 227                 return 0;
 228         }
 229         if (!strcmp(var, "log.showroot")) {
 230                 default_show_root = git_config_bool(var, value);
 231                 return 0;
 232         }
 233         return git_diff_ui_config(var, value);
 234 }
 235
 236 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 237 {
 238         struct rev_info rev;
 239
 240         git_config(git_log_config);
 241         init_revisions(&rev, prefix);
 242         rev.diff = 1;
 243         rev.simplify_history = 0;
 244         cmd_log_init(argc, argv, prefix, &rev);
 245         if (!rev.diffopt.output_format)
 246                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
 247         return cmd_log_walk(&rev);
 248 }
 249
 250 static int show_object(const unsigned char *sha1, int suppress_header)
 251 {
 252         unsigned long size;
 253         enum object_type type;
 254         char *buf = read_sha1_file(sha1, &type, &size);
 255         int offset = 0;
 256
 257         if (!buf)
 258                 return error("Could not read object %s", sha1_to_hex(sha1));
 259
 260         if (suppress_header)
 261                 while (offset < size && buf[offset++] != '\n') {
 262                         int new_offset = offset;
 263                         while (new_offset < size && buf[new_offset++] != '\n')
 264                                 ; /* do nothing */
 265                         offset = new_offset;
 266                 }
 267
 268         if (offset < size)
 269                 fwrite(buf + offset, size - offset, 1, stdout);
 270         free(buf);
 271         return 0;
 272 }
 273
 274 static int show_tree_object(const unsigned char *sha1,
 275                 const char *base, int baselen,
 276                 const char *pathname, unsigned mode, int stage)
 277 {
 278         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
 279         return 0;
 280 }
 281
 282 int cmd_show(int argc, const char **argv, const char *prefix)
 283 {
 284         struct rev_info rev;
 285         struct object_array_entry *objects;
 286         int i, count, ret = 0;
 287
 288         git_config(git_log_config);
 289         init_revisions(&rev, prefix);
 290         rev.diff = 1;
 291         rev.combine_merges = 1;
 292         rev.dense_combined_merges = 1;
 293         rev.always_show_header = 1;
 294         rev.ignore_merges = 0;
 295         rev.no_walk = 1;
 296         cmd_log_init(argc, argv, prefix, &rev);
 297
 298         count = rev.pending.nr;
 299         objects = rev.pending.objects;
 300         for (i = 0; i < count && !ret; i++) {
 301                 struct object *o = objects[i].item;
 302                 const char *name = objects[i].name;
 303                 switch (o->type) {
 304                 case OBJ_BLOB:
 305                         ret = show_object(o->sha1, 0);
 306                         break;
 307                 case OBJ_TAG: {
 308                         struct tag *t = (struct tag *)o;
 309
 310                         printf("%stag %s%s\n\n",
 311                                         diff_get_color(rev.diffopt.color_diff,
 312                                                 DIFF_COMMIT),
 313                                         t->tag,
 314                                         diff_get_color(rev.diffopt.color_diff,
 315                                                 DIFF_RESET));
 316                         ret = show_object(o->sha1, 1);
 317                         objects[i].item = (struct object *)t->tagged;
 318                         i--;
 319                         break;
 320                 }
 321                 case OBJ_TREE:
 322                         printf("%stree %s%s\n\n",
 323                                         diff_get_color(rev.diffopt.color_diff,
 324                                                 DIFF_COMMIT),
 325                                         name,
 326                                         diff_get_color(rev.diffopt.color_diff,
 327                                                 DIFF_RESET));
 328                         read_tree_recursive((struct tree *)o, "", 0, 0, NULL,
 329                                         show_tree_object);
 330                         break;
 331                 case OBJ_COMMIT:
 332                         rev.pending.nr = rev.pending.alloc = 0;
 333                         rev.pending.objects = NULL;
 334                         add_object_array(o, name, &rev.pending);
 335                         ret = cmd_log_walk(&rev);
 336                         break;
 337                 default:
 338                         ret = error("Unknown type: %d", o->type);
 339                 }
 340         }
 341         free(objects);
 342         return ret;
 343 }
 344
 345 /*
 346  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
 347  */
 348 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
 349 {
 350         struct rev_info rev;
 351
 352         git_config(git_log_config);
 353         init_revisions(&rev, prefix);
 354         init_reflog_walk(&rev.reflog_info);
 355         rev.abbrev_commit = 1;
 356         rev.verbose_header = 1;
 357         cmd_log_init(argc, argv, prefix, &rev);
 358
 359         /*
 360          * This means that we override whatever commit format the user gave
 361          * on the cmd line.  Sad, but cmd_log_init() currently doesn't
 362          * allow us to set a different default.
 363          */
 364         rev.commit_format = CMIT_FMT_ONELINE;
 365         rev.always_show_header = 1;
 366
 367         /*
 368          * We get called through "git reflog", so unlike the other log
 369          * routines, we need to set up our pager manually..
 370          */
 371         setup_pager();
 372
 373         return cmd_log_walk(&rev);
 374 }
 375
 376 int cmd_log(int argc, const char **argv, const char *prefix)
 377 {
 378         struct rev_info rev;
 379
 380         git_config(git_log_config);
 381         init_revisions(&rev, prefix);
 382         rev.always_show_header = 1;
 383         cmd_log_init(argc, argv, prefix, &rev);
 384         return cmd_log_walk(&rev);
 385 }
 386
 387 /* format-patch */
 388 #define FORMAT_PATCH_NAME_MAX 64
 389
 390 static int istitlechar(char c)
 391 {
 392         return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') ||
 393                 (c >= '0' && c <= '9') || c == '.' || c == '_';
 394 }
 395
 396 static char *extra_headers = NULL;
 397 static int extra_headers_size = 0;
 398 static const char *fmt_patch_suffix = ".patch";
 399
 400 static int git_format_config(const char *var, const char *value)
 401 {
 402         if (!strcmp(var, "format.headers")) {
 403                 int len;
 404
 405                 if (!value)
 406                         die("format.headers without value");
 407                 len = strlen(value);
 408                 extra_headers_size += len + 1;
 409                 extra_headers = xrealloc(extra_headers, extra_headers_size);
 410                 extra_headers[extra_headers_size - len - 1] = 0;
 411                 strcat(extra_headers, value);
 412                 return 0;
 413         }
 414         if (!strcmp(var, "format.suffix")) {
 415                 if (!value)
 416                         die("format.suffix without value");
 417                 fmt_patch_suffix = xstrdup(value);
 418                 return 0;
 419         }
 420         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
 421                 return 0;
 422         }
 423
 424         return git_log_config(var, value);
 425 }
 426
 427
 428 static FILE *realstdout = NULL;
 429 static const char *output_directory = NULL;
 430
 431 static int reopen_stdout(struct commit *commit, int nr, int keep_subject,
 432                          int numbered_files)
 433 {
 434         char filename[PATH_MAX];
 435         char *sol;
 436         int len = 0;
 437         int suffix_len = strlen(fmt_patch_suffix) + 1;
 438
 439         if (output_directory) {
 440                 if (strlen(output_directory) >=
 441                     sizeof(filename) - FORMAT_PATCH_NAME_MAX - suffix_len)
 442                         return error("name of output directory is too long");
 443                 strlcpy(filename, output_directory, sizeof(filename) - suffix_len);
 444                 len = strlen(filename);
 445                 if (filename[len - 1] != '/')
 446                         filename[len++] = '/';
 447         }
 448
 449         if (numbered_files) {
 450                 sprintf(filename + len, "%d", nr);
 451                 len = strlen(filename);
 452
 453         } else {
 454                 sprintf(filename + len, "%04d", nr);
 455                 len = strlen(filename);
 456
 457                 sol = strstr(commit->buffer, "\n\n");
 458                 if (sol) {
 459                         int j, space = 1;
 460
 461                         sol += 2;
 462                         /* strip [PATCH] or [PATCH blabla] */
 463                         if (!keep_subject && !prefixcmp(sol, "[PATCH")) {
 464                                 char *eos = strchr(sol + 6, ']');
 465                                 if (eos) {
 466                                         while (isspace(*eos))
 467                                                 eos++;
 468                                         sol = eos;
 469                                 }
 470                         }
 471
 472                         for (j = 0;
 473                              j < FORMAT_PATCH_NAME_MAX - suffix_len - 5 &&
 474                                      len < sizeof(filename) - suffix_len &&
 475                                      sol[j] && sol[j] != '\n';
 476                              j++) {
 477                                 if (istitlechar(sol[j])) {
 478                                         if (space) {
 479                                                 filename[len++] = '-';
 480                                                 space = 0;
 481                                         }
 482                                         filename[len++] = sol[j];
 483                                         if (sol[j] == '.')
 484                                                 while (sol[j + 1] == '.')
 485                                                         j++;
 486                                 } else
 487                                         space = 1;
 488                         }
 489                         while (filename[len - 1] == '.'
 490                                || filename[len - 1] == '-')
 491                                 len--;
 492                         filename[len] = 0;
 493                 }
 494                 if (len + suffix_len >= sizeof(filename))
 495                         return error("Patch pathname too long");
 496                 strcpy(filename + len, fmt_patch_suffix);
 497         }
 498
 499         fprintf(realstdout, "%s\n", filename);
 500         if (freopen(filename, "w", stdout) == NULL)
 501                 return error("Cannot open patch file %s",filename);
 502
 503         return 0;
 504 }
 505
 506 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids, const char *prefix)
 507 {
 508         struct rev_info check_rev;
 509         struct commit *commit;
 510         struct object *o1, *o2;
 511         unsigned flags1, flags2;
 512
 513         if (rev->pending.nr != 2)
 514                 die("Need exactly one range.");
 515
 516         o1 = rev->pending.objects[0].item;
 517         flags1 = o1->flags;
 518         o2 = rev->pending.objects[1].item;
 519         flags2 = o2->flags;
 520
 521         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
 522                 die("Not a range.");
 523
 524         init_patch_ids(ids);
 525
 526         /* given a range a..b get all patch ids for b..a */
 527         init_revisions(&check_rev, prefix);
 528         o1->flags ^= UNINTERESTING;
 529         o2->flags ^= UNINTERESTING;
 530         add_pending_object(&check_rev, o1, "o1");
 531         add_pending_object(&check_rev, o2, "o2");
 532         prepare_revision_walk(&check_rev);
 533
 534         while ((commit = get_revision(&check_rev)) != NULL) {
 535                 /* ignore merges */
 536                 if (commit->parents && commit->parents->next)
 537                         continue;
 538
 539                 add_commit_patch_id(commit, ids);
 540         }
 541
 542         /* reset for next revision walk */
 543         clear_commit_marks((struct commit *)o1,
 544                         SEEN | UNINTERESTING | SHOWN | ADDED);
 545         clear_commit_marks((struct commit *)o2,
 546                         SEEN | UNINTERESTING | SHOWN | ADDED);
 547         o1->flags = flags1;
 548         o2->flags = flags2;
 549 }
 550
 551 static void gen_message_id(char *dest, unsigned int length, char *base)
 552 {
 553         const char *committer = git_committer_info(-1);
 554         const char *email_start = strrchr(committer, '<');
 555         const char *email_end = strrchr(committer, '>');
 556         if(!email_start || !email_end || email_start > email_end - 1)
 557                 die("Could not extract email from committer identity.");
 558         snprintf(dest, length, "%s.%lu.git.%.*s", base,
 559                  (unsigned long) time(NULL),
 560                  (int)(email_end - email_start - 1), email_start + 1);
 561 }
 562
 563 static const char *clean_message_id(const char *msg_id)
 564 {
 565         char ch;
 566         const char *a, *z, *m;
 567
 568         m = msg_id;
 569         while ((ch = *m) && (isspace(ch) || (ch == '<')))
 570                 m++;
 571         a = m;
 572         z = NULL;
 573         while ((ch = *m)) {
 574                 if (!isspace(ch) && (ch != '>'))
 575                         z = m;
 576                 m++;
 577         }
 578         if (!z)
 579                 die("insane in-reply-to: %s", msg_id);
 580         if (++z == m)
 581                 return a;
 582         return xmemdupz(a, z - a);
 583 }
 584
 585 int cmd_format_patch(int argc, const char **argv, const char *prefix)
 586 {
 587         struct commit *commit;
 588         struct commit **list = NULL;
 589         struct rev_info rev;
 590         int nr = 0, total, i, j;
 591         int use_stdout = 0;
 592         int numbered = 0;
 593         int start_number = -1;
 594         int keep_subject = 0;
 595         int numbered_files = 0;         /* _just_ numbers */
 596         int subject_prefix = 0;
 597         int ignore_if_in_upstream = 0;
 598         int thread = 0;
 599         const char *in_reply_to = NULL;
 600         struct patch_ids ids;
 601         char *add_signoff = NULL;
 602         char message_id[1024];
 603         char ref_message_id[1024];
 604
 605         git_config(git_format_config);
 606         init_revisions(&rev, prefix);
 607         rev.commit_format = CMIT_FMT_EMAIL;
 608         rev.verbose_header = 1;
 609         rev.diff = 1;
 610         rev.combine_merges = 0;
 611         rev.ignore_merges = 1;
 612         rev.diffopt.msg_sep = "";
 613         rev.diffopt.recursive = 1;
 614
 615         rev.subject_prefix = fmt_patch_subject_prefix;
 616         rev.extra_headers = extra_headers;
 617
 618         /*
 619          * Parse the arguments before setup_revisions(), or something
 620          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
 621          * possibly a valid SHA1.
 622          */
 623         for (i = 1, j = 1; i < argc; i++) {
 624                 if (!strcmp(argv[i], "--stdout"))
 625                         use_stdout = 1;
 626                 else if (!strcmp(argv[i], "-n") ||
 627                                 !strcmp(argv[i], "--numbered"))
 628                         numbered = 1;
 629                 else if (!prefixcmp(argv[i], "--start-number="))
 630                         start_number = strtol(argv[i] + 15, NULL, 10);
 631                 else if (!strcmp(argv[i], "--numbered-files"))
 632                         numbered_files = 1;
 633                 else if (!strcmp(argv[i], "--start-number")) {
 634                         i++;
 635                         if (i == argc)
 636                                 die("Need a number for --start-number");
 637                         start_number = strtol(argv[i], NULL, 10);
 638                 }
 639                 else if (!strcmp(argv[i], "-k") ||
 640                                 !strcmp(argv[i], "--keep-subject")) {
 641                         keep_subject = 1;
 642                         rev.total = -1;
 643                 }
 644                 else if (!strcmp(argv[i], "--output-directory") ||
 645                          !strcmp(argv[i], "-o")) {
 646                         i++;
 647                         if (argc <= i)
 648                                 die("Which directory?");
 649                         if (output_directory)
 650                                 die("Two output directories?");
 651                         output_directory = argv[i];
 652                 }
 653                 else if (!strcmp(argv[i], "--signoff") ||
 654                          !strcmp(argv[i], "-s")) {
 655                         const char *committer;
 656                         const char *endpos;
 657                         committer = git_committer_info(1);
 658                         endpos = strchr(committer, '>');
 659                         if (!endpos)
 660                                 die("bogos committer info %s\n", committer);
 661                         add_signoff = xmemdupz(committer, endpos - committer + 1);
 662                 }
 663                 else if (!strcmp(argv[i], "--attach")) {
 664                         rev.mime_boundary = git_version_string;
 665                         rev.no_inline = 1;
 666                 }
 667                 else if (!prefixcmp(argv[i], "--attach=")) {
 668                         rev.mime_boundary = argv[i] + 9;
 669                         rev.no_inline = 1;
 670                 }
 671                 else if (!strcmp(argv[i], "--inline")) {
 672                         rev.mime_boundary = git_version_string;
 673                         rev.no_inline = 0;
 674                 }
 675                 else if (!prefixcmp(argv[i], "--inline=")) {
 676                         rev.mime_boundary = argv[i] + 9;
 677                         rev.no_inline = 0;
 678                 }
 679                 else if (!strcmp(argv[i], "--ignore-if-in-upstream"))
 680                         ignore_if_in_upstream = 1;
 681                 else if (!strcmp(argv[i], "--thread"))
 682                         thread = 1;
 683                 else if (!prefixcmp(argv[i], "--in-reply-to="))
 684                         in_reply_to = argv[i] + 14;
 685                 else if (!strcmp(argv[i], "--in-reply-to")) {
 686                         i++;
 687                         if (i == argc)
 688                                 die("Need a Message-Id for --in-reply-to");
 689                         in_reply_to = argv[i];
 690                 } else if (!prefixcmp(argv[i], "--subject-prefix=")) {
 691                         subject_prefix = 1;
 692                         rev.subject_prefix = argv[i] + 17;
 693                 } else if (!prefixcmp(argv[i], "--suffix="))
 694                         fmt_patch_suffix = argv[i] + 9;
 695                 else
 696                         argv[j++] = argv[i];
 697         }
 698         argc = j;
 699
 700         if (start_number < 0)
 701                 start_number = 1;
 702         if (numbered && keep_subject)
 703                 die ("-n and -k are mutually exclusive.");
 704         if (keep_subject && subject_prefix)
 705                 die ("--subject-prefix and -k are mutually exclusive.");
 706         if (numbered_files && use_stdout)
 707                 die ("--numbered-files and --stdout are mutually exclusive.");
 708
 709         argc = setup_revisions(argc, argv, &rev, "HEAD");
 710         if (argc > 1)
 711                 die ("unrecognized argument: %s", argv[1]);
 712
 713         if (!rev.diffopt.output_format)
 714                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY | DIFF_FORMAT_PATCH;
 715
 716         if (!rev.diffopt.text)
 717                 rev.diffopt.binary = 1;
 718
 719         if (!output_directory && !use_stdout)
 720                 output_directory = prefix;
 721
 722         if (output_directory) {
 723                 if (use_stdout)
 724                         die("standard output, or directory, which one?");
 725                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
 726                         die("Could not create directory %s",
 727                             output_directory);
 728         }
 729
 730         if (rev.pending.nr == 1) {
 731                 if (rev.max_count < 0 && !rev.show_root_diff) {
 732                         /*
 733                          * This is traditional behaviour of "git format-patch
 734                          * origin" that prepares what the origin side still
 735                          * does not have.
 736                          */
 737                         rev.pending.objects[0].item->flags |= UNINTERESTING;
 738                         add_head(&rev);
 739                 }
 740                 /*
 741                  * Otherwise, it is "format-patch -22 HEAD", and/or
 742                  * "format-patch --root HEAD".  The user wants
 743                  * get_revision() to do the usual traversal.
 744                  */
 745         }
 746
 747         if (ignore_if_in_upstream)
 748                 get_patch_ids(&rev, &ids, prefix);
 749
 750         if (!use_stdout)
 751                 realstdout = xfdopen(xdup(1), "w");
 752
 753         prepare_revision_walk(&rev);
 754         while ((commit = get_revision(&rev)) != NULL) {
 755                 /* ignore merges */
 756                 if (commit->parents && commit->parents->next)
 757                         continue;
 758
 759                 if (ignore_if_in_upstream &&
 760                                 has_commit_patch_id(commit, &ids))
 761                         continue;
 762
 763                 nr++;
 764                 list = xrealloc(list, nr * sizeof(list[0]));
 765                 list[nr - 1] = commit;
 766         }
 767         total = nr;
 768         if (numbered)
 769                 rev.total = total + start_number - 1;
 770         rev.add_signoff = add_signoff;
 771         if (in_reply_to)
 772                 rev.ref_message_id = clean_message_id(in_reply_to);
 773         while (0 <= --nr) {
 774                 int shown;
 775                 commit = list[nr];
 776                 rev.nr = total - nr + (start_number - 1);
 777                 /* Make the second and subsequent mails replies to the first */
 778                 if (thread) {
 779                         if (nr == (total - 2)) {
 780                                 strncpy(ref_message_id, message_id,
 781                                         sizeof(ref_message_id));
 782                                 ref_message_id[sizeof(ref_message_id)-1]='\0';
 783                                 rev.ref_message_id = ref_message_id;
 784                         }
 785                         gen_message_id(message_id, sizeof(message_id),
 786                                        sha1_to_hex(commit->object.sha1));
 787                         rev.message_id = message_id;
 788                 }
 789                 if (!use_stdout)
 790                         if (reopen_stdout(commit, rev.nr, keep_subject,
 791                                           numbered_files))
 792                                 die("Failed to create output files");
 793                 shown = log_tree_commit(&rev, commit);
 794                 free(commit->buffer);
 795                 commit->buffer = NULL;
 796
 797                 /* We put one extra blank line between formatted
 798                  * patches and this flag is used by log-tree code
 799                  * to see if it needs to emit a LF before showing
 800                  * the log; when using one file per patch, we do
 801                  * not want the extra blank line.
 802                  */
 803                 if (!use_stdout)
 804                         rev.shown_one = 0;
 805                 if (shown) {
 806                         if (rev.mime_boundary)
 807                                 printf("\n--%s%s--\n\n\n",
 808                                        mime_boundary_leader,
 809                                        rev.mime_boundary);
 810                         else
 811                                 printf("-- \n%s\n\n", git_version_string);
 812                 }
 813                 if (!use_stdout)
 814                         fclose(stdout);
 815         }
 816         free(list);
 817         if (ignore_if_in_upstream)
 818                 free_patch_ids(&ids);
 819         return 0;
 820 }
 821
 822 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
 823 {
 824         unsigned char sha1[20];
 825         if (get_sha1(arg, sha1) == 0) {
 826                 struct commit *commit = lookup_commit_reference(sha1);
 827                 if (commit) {
 828                         commit->object.flags |= flags;
 829                         add_pending_object(revs, &commit->object, arg);
 830                         return 0;
 831                 }
 832         }
 833         return -1;
 834 }
 835
 836 static const char cherry_usage[] =
 837 "git-cherry [-v] <upstream> [<head>] [<limit>]";
 838 int cmd_cherry(int argc, const char **argv, const char *prefix)
 839 {
 840         struct rev_info revs;
 841         struct patch_ids ids;
 842         struct commit *commit;
 843         struct commit_list *list = NULL;
 844         const char *upstream;
 845         const char *head = "HEAD";
 846         const char *limit = NULL;
 847         int verbose = 0;
 848
 849         if (argc > 1 && !strcmp(argv[1], "-v")) {
 850                 verbose = 1;
 851                 argc--;
 852                 argv++;
 853         }
 854
 855         switch (argc) {
 856         case 4:
 857                 limit = argv[3];
 858                 /* FALLTHROUGH */
 859         case 3:
 860                 head = argv[2];
 861                 /* FALLTHROUGH */
 862         case 2:
 863                 upstream = argv[1];
 864                 break;
 865         default:
 866                 usage(cherry_usage);
 867         }
 868
 869         init_revisions(&revs, prefix);
 870         revs.diff = 1;
 871         revs.combine_merges = 0;
 872         revs.ignore_merges = 1;
 873         revs.diffopt.recursive = 1;
 874
 875         if (add_pending_commit(head, &revs, 0))
 876                 die("Unknown commit %s", head);
 877         if (add_pending_commit(upstream, &revs, UNINTERESTING))
 878                 die("Unknown commit %s", upstream);
 879
 880         /* Don't say anything if head and upstream are the same. */
 881         if (revs.pending.nr == 2) {
 882                 struct object_array_entry *o = revs.pending.objects;
 883                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
 884                         return 0;
 885         }
 886
 887         get_patch_ids(&revs, &ids, prefix);
 888
 889         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
 890                 die("Unknown commit %s", limit);
 891
 892         /* reverse the list of commits */
 893         prepare_revision_walk(&revs);
 894         while ((commit = get_revision(&revs)) != NULL) {
 895                 /* ignore merges */
 896                 if (commit->parents && commit->parents->next)
 897                         continue;
 898
 899                 commit_list_insert(commit, &list);
 900         }
 901
 902         while (list) {
 903                 char sign = '+';
 904
 905                 commit = list->item;
 906                 if (has_commit_patch_id(commit, &ids))
 907                         sign = '-';
 908
 909                 if (verbose) {
 910                         struct strbuf buf;
 911                         strbuf_init(&buf, 0);
 912                         pretty_print_commit(CMIT_FMT_ONELINE, commit,
 913                                             &buf, 0, NULL, NULL, 0, 0);
 914                         printf("%c %s %s\n", sign,
 915                                sha1_to_hex(commit->object.sha1), buf.buf);
 916                         strbuf_release(&buf);
 917                 }
 918                 else {
 919                         printf("%c %s\n", sign,
 920                                sha1_to_hex(commit->object.sha1));
 921                 }
 922
 923                 list = list->next;
 924         }
 925
 926         free_patch_ids(&ids);
 927         return 0;
 928 }