git.oblomov.eu Git - git/blob - builtin-show-branch.c

   1 #include "cache.h"
   2 #include "commit.h"
   3 #include "refs.h"
   4 #include "builtin.h"
   5 #include "color.h"
   6
   7 static const char show_branch_usage[] =
   8 "git show-branch [--sparse] [--current] [--all] [--remotes] [--topo-order] [--more=count | --list | --independent | --merge-base ] [--topics] [<refs>...] | --reflog[=n[,b]] <branch>";
   9 static const char show_branch_usage_reflog[] =
  10 "--reflog is incompatible with --all, --remotes, --independent or --merge-base";
  11
  12 static int showbranch_use_color = -1;
  13 static char column_colors[][COLOR_MAXLEN] = {
  14         GIT_COLOR_RED,
  15         GIT_COLOR_GREEN,
  16         GIT_COLOR_YELLOW,
  17         GIT_COLOR_BLUE,
  18         GIT_COLOR_MAGENTA,
  19         GIT_COLOR_CYAN,
  20 };
  21
  22 #define COLUMN_COLORS_MAX (ARRAY_SIZE(column_colors))
  23
  24 static int default_num;
  25 static int default_alloc;
  26 static const char **default_arg;
  27
  28 #define UNINTERESTING   01
  29
  30 #define REV_SHIFT        2
  31 #define MAX_REVS        (FLAG_BITS - REV_SHIFT) /* should not exceed bits_per_int - REV_SHIFT */
  32
  33 #define DEFAULT_REFLOG  4
  34
  35 static const char *get_color_code(int idx)
  36 {
  37         if (showbranch_use_color)
  38                 return column_colors[idx];
  39         return "";
  40 }
  41
  42 static const char *get_color_reset_code(void)
  43 {
  44         if (showbranch_use_color)
  45                 return GIT_COLOR_RESET;
  46         return "";
  47 }
  48
  49 static struct commit *interesting(struct commit_list *list)
  50 {
  51         while (list) {
  52                 struct commit *commit = list->item;
  53                 list = list->next;
  54                 if (commit->object.flags & UNINTERESTING)
  55                         continue;
  56                 return commit;
  57         }
  58         return NULL;
  59 }
  60
  61 static struct commit *pop_one_commit(struct commit_list **list_p)
  62 {
  63         struct commit *commit;
  64         struct commit_list *list;
  65         list = *list_p;
  66         commit = list->item;
  67         *list_p = list->next;
  68         free(list);
  69         return commit;
  70 }
  71
  72 struct commit_name {
  73         const char *head_name; /* which head's ancestor? */
  74         int generation; /* how many parents away from head_name */
  75 };
  76
  77 /* Name the commit as nth generation ancestor of head_name;
  78  * we count only the first-parent relationship for naming purposes.
  79  */
  80 static void name_commit(struct commit *commit, const char *head_name, int nth)
  81 {
  82         struct commit_name *name;
  83         if (!commit->util)
  84                 commit->util = xmalloc(sizeof(struct commit_name));
  85         name = commit->util;
  86         name->head_name = head_name;
  87         name->generation = nth;
  88 }
  89
  90 /* Parent is the first parent of the commit.  We may name it
  91  * as (n+1)th generation ancestor of the same head_name as
  92  * commit is nth generation ancestor of, if that generation
  93  * number is better than the name it already has.
  94  */
  95 static void name_parent(struct commit *commit, struct commit *parent)
  96 {
  97         struct commit_name *commit_name = commit->util;
  98         struct commit_name *parent_name = parent->util;
  99         if (!commit_name)
 100                 return;
 101         if (!parent_name ||
 102             commit_name->generation + 1 < parent_name->generation)
 103                 name_commit(parent, commit_name->head_name,
 104                             commit_name->generation + 1);
 105 }
 106
 107 static int name_first_parent_chain(struct commit *c)
 108 {
 109         int i = 0;
 110         while (c) {
 111                 struct commit *p;
 112                 if (!c->util)
 113                         break;
 114                 if (!c->parents)
 115                         break;
 116                 p = c->parents->item;
 117                 if (!p->util) {
 118                         name_parent(c, p);
 119                         i++;
 120                 }
 121                 else
 122                         break;
 123                 c = p;
 124         }
 125         return i;
 126 }
 127
 128 static void name_commits(struct commit_list *list,
 129                          struct commit **rev,
 130                          char **ref_name,
 131                          int num_rev)
 132 {
 133         struct commit_list *cl;
 134         struct commit *c;
 135         int i;
 136
 137         /* First give names to the given heads */
 138         for (cl = list; cl; cl = cl->next) {
 139                 c = cl->item;
 140                 if (c->util)
 141                         continue;
 142                 for (i = 0; i < num_rev; i++) {
 143                         if (rev[i] == c) {
 144                                 name_commit(c, ref_name[i], 0);
 145                                 break;
 146                         }
 147                 }
 148         }
 149
 150         /* Then commits on the first parent ancestry chain */
 151         do {
 152                 i = 0;
 153                 for (cl = list; cl; cl = cl->next) {
 154                         i += name_first_parent_chain(cl->item);
 155                 }
 156         } while (i);
 157
 158         /* Finally, any unnamed commits */
 159         do {
 160                 i = 0;
 161                 for (cl = list; cl; cl = cl->next) {
 162                         struct commit_list *parents;
 163                         struct commit_name *n;
 164                         int nth;
 165                         c = cl->item;
 166                         if (!c->util)
 167                                 continue;
 168                         n = c->util;
 169                         parents = c->parents;
 170                         nth = 0;
 171                         while (parents) {
 172                                 struct commit *p = parents->item;
 173                                 char newname[1000], *en;
 174                                 parents = parents->next;
 175                                 nth++;
 176                                 if (p->util)
 177                                         continue;
 178                                 en = newname;
 179                                 switch (n->generation) {
 180                                 case 0:
 181                                         en += sprintf(en, "%s", n->head_name);
 182                                         break;
 183                                 case 1:
 184                                         en += sprintf(en, "%s^", n->head_name);
 185                                         break;
 186                                 default:
 187                                         en += sprintf(en, "%s~%d",
 188                                                 n->head_name, n->generation);
 189                                         break;
 190                                 }
 191                                 if (nth == 1)
 192                                         en += sprintf(en, "^");
 193                                 else
 194                                         en += sprintf(en, "^%d", nth);
 195                                 name_commit(p, xstrdup(newname), 0);
 196                                 i++;
 197                                 name_first_parent_chain(p);
 198                         }
 199                 }
 200         } while (i);
 201 }
 202
 203 static int mark_seen(struct commit *commit, struct commit_list **seen_p)
 204 {
 205         if (!commit->object.flags) {
 206                 commit_list_insert(commit, seen_p);
 207                 return 1;
 208         }
 209         return 0;
 210 }
 211
 212 static void join_revs(struct commit_list **list_p,
 213                       struct commit_list **seen_p,
 214                       int num_rev, int extra)
 215 {
 216         int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 217         int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 218
 219         while (*list_p) {
 220                 struct commit_list *parents;
 221                 int still_interesting = !!interesting(*list_p);
 222                 struct commit *commit = pop_one_commit(list_p);
 223                 int flags = commit->object.flags & all_mask;
 224
 225                 if (!still_interesting && extra <= 0)
 226                         break;
 227
 228                 mark_seen(commit, seen_p);
 229                 if ((flags & all_revs) == all_revs)
 230                         flags |= UNINTERESTING;
 231                 parents = commit->parents;
 232
 233                 while (parents) {
 234                         struct commit *p = parents->item;
 235                         int this_flag = p->object.flags;
 236                         parents = parents->next;
 237                         if ((this_flag & flags) == flags)
 238                                 continue;
 239                         if (!p->object.parsed)
 240                                 parse_commit(p);
 241                         if (mark_seen(p, seen_p) && !still_interesting)
 242                                 extra--;
 243                         p->object.flags |= flags;
 244                         insert_by_date(p, list_p);
 245                 }
 246         }
 247
 248         /*
 249          * Postprocess to complete well-poisoning.
 250          *
 251          * At this point we have all the commits we have seen in
 252          * seen_p list.  Mark anything that can be reached from
 253          * uninteresting commits not interesting.
 254          */
 255         for (;;) {
 256                 int changed = 0;
 257                 struct commit_list *s;
 258                 for (s = *seen_p; s; s = s->next) {
 259                         struct commit *c = s->item;
 260                         struct commit_list *parents;
 261
 262                         if (((c->object.flags & all_revs) != all_revs) &&
 263                             !(c->object.flags & UNINTERESTING))
 264                                 continue;
 265
 266                         /* The current commit is either a merge base or
 267                          * already uninteresting one.  Mark its parents
 268                          * as uninteresting commits _only_ if they are
 269                          * already parsed.  No reason to find new ones
 270                          * here.
 271                          */
 272                         parents = c->parents;
 273                         while (parents) {
 274                                 struct commit *p = parents->item;
 275                                 parents = parents->next;
 276                                 if (!(p->object.flags & UNINTERESTING)) {
 277                                         p->object.flags |= UNINTERESTING;
 278                                         changed = 1;
 279                                 }
 280                         }
 281                 }
 282                 if (!changed)
 283                         break;
 284         }
 285 }
 286
 287 static void show_one_commit(struct commit *commit, int no_name)
 288 {
 289         struct strbuf pretty = STRBUF_INIT;
 290         const char *pretty_str = "(unavailable)";
 291         struct commit_name *name = commit->util;
 292
 293         if (commit->object.parsed) {
 294                 pretty_print_commit(CMIT_FMT_ONELINE, commit,
 295                                     &pretty, 0, NULL, NULL, 0, 0);
 296                 pretty_str = pretty.buf;
 297         }
 298         if (!prefixcmp(pretty_str, "[PATCH] "))
 299                 pretty_str += 8;
 300
 301         if (!no_name) {
 302                 if (name && name->head_name) {
 303                         printf("[%s", name->head_name);
 304                         if (name->generation) {
 305                                 if (name->generation == 1)
 306                                         printf("^");
 307                                 else
 308                                         printf("~%d", name->generation);
 309                         }
 310                         printf("] ");
 311                 }
 312                 else
 313                         printf("[%s] ",
 314                                find_unique_abbrev(commit->object.sha1, 7));
 315         }
 316         puts(pretty_str);
 317         strbuf_release(&pretty);
 318 }
 319
 320 static char *ref_name[MAX_REVS + 1];
 321 static int ref_name_cnt;
 322
 323 static const char *find_digit_prefix(const char *s, int *v)
 324 {
 325         const char *p;
 326         int ver;
 327         char ch;
 328
 329         for (p = s, ver = 0;
 330              '0' <= (ch = *p) && ch <= '9';
 331              p++)
 332                 ver = ver * 10 + ch - '0';
 333         *v = ver;
 334         return p;
 335 }
 336
 337
 338 static int version_cmp(const char *a, const char *b)
 339 {
 340         while (1) {
 341                 int va, vb;
 342
 343                 a = find_digit_prefix(a, &va);
 344                 b = find_digit_prefix(b, &vb);
 345                 if (va != vb)
 346                         return va - vb;
 347
 348                 while (1) {
 349                         int ca = *a;
 350                         int cb = *b;
 351                         if ('0' <= ca && ca <= '9')
 352                                 ca = 0;
 353                         if ('0' <= cb && cb <= '9')
 354                                 cb = 0;
 355                         if (ca != cb)
 356                                 return ca - cb;
 357                         if (!ca)
 358                                 break;
 359                         a++;
 360                         b++;
 361                 }
 362                 if (!*a && !*b)
 363                         return 0;
 364         }
 365 }
 366
 367 static int compare_ref_name(const void *a_, const void *b_)
 368 {
 369         const char * const*a = a_, * const*b = b_;
 370         return version_cmp(*a, *b);
 371 }
 372
 373 static void sort_ref_range(int bottom, int top)
 374 {
 375         qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
 376               compare_ref_name);
 377 }
 378
 379 static int append_ref(const char *refname, const unsigned char *sha1,
 380                       int allow_dups)
 381 {
 382         struct commit *commit = lookup_commit_reference_gently(sha1, 1);
 383         int i;
 384
 385         if (!commit)
 386                 return 0;
 387
 388         if (!allow_dups) {
 389                 /* Avoid adding the same thing twice */
 390                 for (i = 0; i < ref_name_cnt; i++)
 391                         if (!strcmp(refname, ref_name[i]))
 392                                 return 0;
 393         }
 394         if (MAX_REVS <= ref_name_cnt) {
 395                 warning("ignoring %s; cannot handle more than %d refs",
 396                         refname, MAX_REVS);
 397                 return 0;
 398         }
 399         ref_name[ref_name_cnt++] = xstrdup(refname);
 400         ref_name[ref_name_cnt] = NULL;
 401         return 0;
 402 }
 403
 404 static int append_head_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 405 {
 406         unsigned char tmp[20];
 407         int ofs = 11;
 408         if (prefixcmp(refname, "refs/heads/"))
 409                 return 0;
 410         /* If both heads/foo and tags/foo exists, get_sha1 would
 411          * get confused.
 412          */
 413         if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
 414                 ofs = 5;
 415         return append_ref(refname + ofs, sha1, 0);
 416 }
 417
 418 static int append_remote_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 419 {
 420         unsigned char tmp[20];
 421         int ofs = 13;
 422         if (prefixcmp(refname, "refs/remotes/"))
 423                 return 0;
 424         /* If both heads/foo and tags/foo exists, get_sha1 would
 425          * get confused.
 426          */
 427         if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
 428                 ofs = 5;
 429         return append_ref(refname + ofs, sha1, 0);
 430 }
 431
 432 static int append_tag_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 433 {
 434         if (prefixcmp(refname, "refs/tags/"))
 435                 return 0;
 436         return append_ref(refname + 5, sha1, 0);
 437 }
 438
 439 static const char *match_ref_pattern = NULL;
 440 static int match_ref_slash = 0;
 441 static int count_slash(const char *s)
 442 {
 443         int cnt = 0;
 444         while (*s)
 445                 if (*s++ == '/')
 446                         cnt++;
 447         return cnt;
 448 }
 449
 450 static int append_matching_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 451 {
 452         /* we want to allow pattern hold/<asterisk> to show all
 453          * branches under refs/heads/hold/, and v0.99.9? to show
 454          * refs/tags/v0.99.9a and friends.
 455          */
 456         const char *tail;
 457         int slash = count_slash(refname);
 458         for (tail = refname; *tail && match_ref_slash < slash; )
 459                 if (*tail++ == '/')
 460                         slash--;
 461         if (!*tail)
 462                 return 0;
 463         if (fnmatch(match_ref_pattern, tail, 0))
 464                 return 0;
 465         if (!prefixcmp(refname, "refs/heads/"))
 466                 return append_head_ref(refname, sha1, flag, cb_data);
 467         if (!prefixcmp(refname, "refs/tags/"))
 468                 return append_tag_ref(refname, sha1, flag, cb_data);
 469         return append_ref(refname, sha1, 0);
 470 }
 471
 472 static void snarf_refs(int head, int remotes)
 473 {
 474         if (head) {
 475                 int orig_cnt = ref_name_cnt;
 476                 for_each_ref(append_head_ref, NULL);
 477                 sort_ref_range(orig_cnt, ref_name_cnt);
 478         }
 479         if (remotes) {
 480                 int orig_cnt = ref_name_cnt;
 481                 for_each_ref(append_remote_ref, NULL);
 482                 sort_ref_range(orig_cnt, ref_name_cnt);
 483         }
 484 }
 485
 486 static int rev_is_head(char *head, int headlen, char *name,
 487                        unsigned char *head_sha1, unsigned char *sha1)
 488 {
 489         if ((!head[0]) ||
 490             (head_sha1 && sha1 && hashcmp(head_sha1, sha1)))
 491                 return 0;
 492         if (!prefixcmp(head, "refs/heads/"))
 493                 head += 11;
 494         if (!prefixcmp(name, "refs/heads/"))
 495                 name += 11;
 496         else if (!prefixcmp(name, "heads/"))
 497                 name += 6;
 498         return !strcmp(head, name);
 499 }
 500
 501 static int show_merge_base(struct commit_list *seen, int num_rev)
 502 {
 503         int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 504         int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 505         int exit_status = 1;
 506
 507         while (seen) {
 508                 struct commit *commit = pop_one_commit(&seen);
 509                 int flags = commit->object.flags & all_mask;
 510                 if (!(flags & UNINTERESTING) &&
 511                     ((flags & all_revs) == all_revs)) {
 512                         puts(sha1_to_hex(commit->object.sha1));
 513                         exit_status = 0;
 514                         commit->object.flags |= UNINTERESTING;
 515                 }
 516         }
 517         return exit_status;
 518 }
 519
 520 static int show_independent(struct commit **rev,
 521                             int num_rev,
 522                             char **ref_name,
 523                             unsigned int *rev_mask)
 524 {
 525         int i;
 526
 527         for (i = 0; i < num_rev; i++) {
 528                 struct commit *commit = rev[i];
 529                 unsigned int flag = rev_mask[i];
 530
 531                 if (commit->object.flags == flag)
 532                         puts(sha1_to_hex(commit->object.sha1));
 533                 commit->object.flags |= UNINTERESTING;
 534         }
 535         return 0;
 536 }
 537
 538 static void append_one_rev(const char *av)
 539 {
 540         unsigned char revkey[20];
 541         if (!get_sha1(av, revkey)) {
 542                 append_ref(av, revkey, 0);
 543                 return;
 544         }
 545         if (strchr(av, '*') || strchr(av, '?') || strchr(av, '[')) {
 546                 /* glob style match */
 547                 int saved_matches = ref_name_cnt;
 548                 match_ref_pattern = av;
 549                 match_ref_slash = count_slash(av);
 550                 for_each_ref(append_matching_ref, NULL);
 551                 if (saved_matches == ref_name_cnt &&
 552                     ref_name_cnt < MAX_REVS)
 553                         error("no matching refs with %s", av);
 554                 if (saved_matches + 1 < ref_name_cnt)
 555                         sort_ref_range(saved_matches, ref_name_cnt);
 556                 return;
 557         }
 558         die("bad sha1 reference %s", av);
 559 }
 560
 561 static int git_show_branch_config(const char *var, const char *value, void *cb)
 562 {
 563         if (!strcmp(var, "showbranch.default")) {
 564                 if (!value)
 565                         return config_error_nonbool(var);
 566                 if (default_alloc <= default_num + 1) {
 567                         default_alloc = default_alloc * 3 / 2 + 20;
 568                         default_arg = xrealloc(default_arg, sizeof *default_arg * default_alloc);
 569                 }
 570                 default_arg[default_num++] = xstrdup(value);
 571                 default_arg[default_num] = NULL;
 572                 return 0;
 573         }
 574
 575         if (!strcmp(var, "color.showbranch")) {
 576                 showbranch_use_color = git_config_colorbool(var, value, -1);
 577                 return 0;
 578         }
 579
 580         return git_color_default_config(var, value, cb);
 581 }
 582
 583 static int omit_in_dense(struct commit *commit, struct commit **rev, int n)
 584 {
 585         /* If the commit is tip of the named branches, do not
 586          * omit it.
 587          * Otherwise, if it is a merge that is reachable from only one
 588          * tip, it is not that interesting.
 589          */
 590         int i, flag, count;
 591         for (i = 0; i < n; i++)
 592                 if (rev[i] == commit)
 593                         return 0;
 594         flag = commit->object.flags;
 595         for (i = count = 0; i < n; i++) {
 596                 if (flag & (1u << (i + REV_SHIFT)))
 597                         count++;
 598         }
 599         if (count == 1)
 600                 return 1;
 601         return 0;
 602 }
 603
 604 static void parse_reflog_param(const char *arg, int *cnt, const char **base)
 605 {
 606         char *ep;
 607         *cnt = strtoul(arg, &ep, 10);
 608         if (*ep == ',')
 609                 *base = ep + 1;
 610         else if (*ep)
 611                 die("unrecognized reflog param '%s'", arg);
 612         else
 613                 *base = NULL;
 614         if (*cnt <= 0)
 615                 *cnt = DEFAULT_REFLOG;
 616 }
 617
 618 int cmd_show_branch(int ac, const char **av, const char *prefix)
 619 {
 620         struct commit *rev[MAX_REVS], *commit;
 621         char *reflog_msg[MAX_REVS];
 622         struct commit_list *list = NULL, *seen = NULL;
 623         unsigned int rev_mask[MAX_REVS];
 624         int num_rev, i, extra = 0;
 625         int all_heads = 0, all_remotes = 0;
 626         int all_mask, all_revs;
 627         int lifo = 1;
 628         char head[128];
 629         const char *head_p;
 630         int head_len;
 631         unsigned char head_sha1[20];
 632         int merge_base = 0;
 633         int independent = 0;
 634         int no_name = 0;
 635         int sha1_name = 0;
 636         int shown_merge_point = 0;
 637         int with_current_branch = 0;
 638         int head_at = -1;
 639         int topics = 0;
 640         int dense = 1;
 641         int reflog = 0;
 642         const char *reflog_base = NULL;
 643
 644         git_config(git_show_branch_config, NULL);
 645
 646         if (showbranch_use_color == -1)
 647                 showbranch_use_color = git_use_color_default;
 648
 649         /* If nothing is specified, try the default first */
 650         if (ac == 1 && default_num) {
 651                 ac = default_num + 1;
 652                 av = default_arg - 1; /* ick; we would not address av[0] */
 653         }
 654
 655         while (1 < ac && av[1][0] == '-') {
 656                 const char *arg = av[1];
 657                 if (!strcmp(arg, "--")) {
 658                         ac--; av++;
 659                         break;
 660                 }
 661                 else if (!strcmp(arg, "--all") || !strcmp(arg, "-a"))
 662                         all_heads = all_remotes = 1;
 663                 else if (!strcmp(arg, "--remotes") || !strcmp(arg, "-r"))
 664                         all_remotes = 1;
 665                 else if (!strcmp(arg, "--more"))
 666                         extra = 1;
 667                 else if (!strcmp(arg, "--list"))
 668                         extra = -1;
 669                 else if (!strcmp(arg, "--no-name"))
 670                         no_name = 1;
 671                 else if (!strcmp(arg, "--current"))
 672                         with_current_branch = 1;
 673                 else if (!strcmp(arg, "--sha1-name"))
 674                         sha1_name = 1;
 675                 else if (!prefixcmp(arg, "--more="))
 676                         extra = atoi(arg + 7);
 677                 else if (!strcmp(arg, "--merge-base"))
 678                         merge_base = 1;
 679                 else if (!strcmp(arg, "--independent"))
 680                         independent = 1;
 681                 else if (!strcmp(arg, "--topo-order"))
 682                         lifo = 1;
 683                 else if (!strcmp(arg, "--topics"))
 684                         topics = 1;
 685                 else if (!strcmp(arg, "--sparse"))
 686                         dense = 0;
 687                 else if (!strcmp(arg, "--date-order"))
 688                         lifo = 0;
 689                 else if (!strcmp(arg, "--reflog") || !strcmp(arg, "-g")) {
 690                         reflog = DEFAULT_REFLOG;
 691                 }
 692                 else if (!prefixcmp(arg, "--reflog="))
 693                         parse_reflog_param(arg + 9, &reflog, &reflog_base);
 694                 else if (!prefixcmp(arg, "-g="))
 695                         parse_reflog_param(arg + 3, &reflog, &reflog_base);
 696                 else if (!strcmp(arg, "--color"))
 697                         showbranch_use_color = 1;
 698                 else if (!strcmp(arg, "--no-color"))
 699                         showbranch_use_color = 0;
 700                 else
 701                         usage(show_branch_usage);
 702                 ac--; av++;
 703         }
 704         ac--; av++;
 705
 706         if (extra || reflog) {
 707                 /* "listing" mode is incompatible with
 708                  * independent nor merge-base modes.
 709                  */
 710                 if (independent || merge_base)
 711                         usage(show_branch_usage);
 712                 if (reflog && ((0 < extra) || all_heads || all_remotes))
 713                         /*
 714                          * Asking for --more in reflog mode does not
 715                          * make sense.  --list is Ok.
 716                          *
 717                          * Also --all and --remotes do not make sense either.
 718                          */
 719                         usage(show_branch_usage_reflog);
 720         }
 721
 722         /* If nothing is specified, show all branches by default */
 723         if (ac + all_heads + all_remotes == 0)
 724                 all_heads = 1;
 725
 726         if (reflog) {
 727                 unsigned char sha1[20];
 728                 char nth_desc[256];
 729                 char *ref;
 730                 int base = 0;
 731
 732                 if (ac == 0) {
 733                         static const char *fake_av[2];
 734                         const char *refname;
 735
 736                         refname = resolve_ref("HEAD", sha1, 1, NULL);
 737                         fake_av[0] = xstrdup(refname);
 738                         fake_av[1] = NULL;
 739                         av = fake_av;
 740                         ac = 1;
 741                 }
 742                 if (ac != 1)
 743                         die("--reflog option needs one branch name");
 744
 745                 if (MAX_REVS < reflog)
 746                         die("Only %d entries can be shown at one time.",
 747                             MAX_REVS);
 748                 if (!dwim_ref(*av, strlen(*av), sha1, &ref))
 749                         die("No such ref %s", *av);
 750
 751                 /* Has the base been specified? */
 752                 if (reflog_base) {
 753                         char *ep;
 754                         base = strtoul(reflog_base, &ep, 10);
 755                         if (*ep) {
 756                                 /* Ah, that is a date spec... */
 757                                 unsigned long at;
 758                                 at = approxidate(reflog_base);
 759                                 read_ref_at(ref, at, -1, sha1, NULL,
 760                                             NULL, NULL, &base);
 761                         }
 762                 }
 763
 764                 for (i = 0; i < reflog; i++) {
 765                         char *logmsg, *m;
 766                         const char *msg;
 767                         unsigned long timestamp;
 768                         int tz;
 769
 770                         if (read_ref_at(ref, 0, base+i, sha1, &logmsg,
 771                                         &timestamp, &tz, NULL)) {
 772                                 reflog = i;
 773                                 break;
 774                         }
 775                         msg = strchr(logmsg, '\t');
 776                         if (!msg)
 777                                 msg = "(none)";
 778                         else
 779                                 msg++;
 780                         m = xmalloc(strlen(msg) + 200);
 781                         sprintf(m, "(%s) %s",
 782                                 show_date(timestamp, tz, 1),
 783                                 msg);
 784                         reflog_msg[i] = m;
 785                         free(logmsg);
 786                         sprintf(nth_desc, "%s@{%d}", *av, base+i);
 787                         append_ref(nth_desc, sha1, 1);
 788                 }
 789         }
 790         else if (all_heads + all_remotes)
 791                 snarf_refs(all_heads, all_remotes);
 792         else {
 793                 while (0 < ac) {
 794                         append_one_rev(*av);
 795                         ac--; av++;
 796                 }
 797         }
 798
 799         head_p = resolve_ref("HEAD", head_sha1, 1, NULL);
 800         if (head_p) {
 801                 head_len = strlen(head_p);
 802                 memcpy(head, head_p, head_len + 1);
 803         }
 804         else {
 805                 head_len = 0;
 806                 head[0] = 0;
 807         }
 808
 809         if (with_current_branch && head_p) {
 810                 int has_head = 0;
 811                 for (i = 0; !has_head && i < ref_name_cnt; i++) {
 812                         /* We are only interested in adding the branch
 813                          * HEAD points at.
 814                          */
 815                         if (rev_is_head(head,
 816                                         head_len,
 817                                         ref_name[i],
 818                                         head_sha1, NULL))
 819                                 has_head++;
 820                 }
 821                 if (!has_head) {
 822                         int offset = !prefixcmp(head, "refs/heads/") ? 11 : 0;
 823                         append_one_rev(head + offset);
 824                 }
 825         }
 826
 827         if (!ref_name_cnt) {
 828                 fprintf(stderr, "No revs to be shown.\n");
 829                 exit(0);
 830         }
 831
 832         for (num_rev = 0; ref_name[num_rev]; num_rev++) {
 833                 unsigned char revkey[20];
 834                 unsigned int flag = 1u << (num_rev + REV_SHIFT);
 835
 836                 if (MAX_REVS <= num_rev)
 837                         die("cannot handle more than %d revs.", MAX_REVS);
 838                 if (get_sha1(ref_name[num_rev], revkey))
 839                         die("'%s' is not a valid ref.", ref_name[num_rev]);
 840                 commit = lookup_commit_reference(revkey);
 841                 if (!commit)
 842                         die("cannot find commit %s (%s)",
 843                             ref_name[num_rev], revkey);
 844                 parse_commit(commit);
 845                 mark_seen(commit, &seen);
 846
 847                 /* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
 848                  * and so on.  REV_SHIFT bits from bit 0 are used for
 849                  * internal bookkeeping.
 850                  */
 851                 commit->object.flags |= flag;
 852                 if (commit->object.flags == flag)
 853                         insert_by_date(commit, &list);
 854                 rev[num_rev] = commit;
 855         }
 856         for (i = 0; i < num_rev; i++)
 857                 rev_mask[i] = rev[i]->object.flags;
 858
 859         if (0 <= extra)
 860                 join_revs(&list, &seen, num_rev, extra);
 861
 862         sort_by_date(&seen);
 863
 864         if (merge_base)
 865                 return show_merge_base(seen, num_rev);
 866
 867         if (independent)
 868                 return show_independent(rev, num_rev, ref_name, rev_mask);
 869
 870         /* Show list; --more=-1 means list-only */
 871         if (1 < num_rev || extra < 0) {
 872                 for (i = 0; i < num_rev; i++) {
 873                         int j;
 874                         int is_head = rev_is_head(head,
 875                                                   head_len,
 876                                                   ref_name[i],
 877                                                   head_sha1,
 878                                                   rev[i]->object.sha1);
 879                         if (extra < 0)
 880                                 printf("%c [%s] ",
 881                                        is_head ? '*' : ' ', ref_name[i]);
 882                         else {
 883                                 for (j = 0; j < i; j++)
 884                                         putchar(' ');
 885                                 printf("%s%c%s [%s] ",
 886                                        get_color_code(i % COLUMN_COLORS_MAX),
 887                                        is_head ? '*' : '!',
 888                                        get_color_reset_code(), ref_name[i]);
 889                         }
 890
 891                         if (!reflog) {
 892                                 /* header lines never need name */
 893                                 show_one_commit(rev[i], 1);
 894                         }
 895                         else
 896                                 puts(reflog_msg[i]);
 897
 898                         if (is_head)
 899                                 head_at = i;
 900                 }
 901                 if (0 <= extra) {
 902                         for (i = 0; i < num_rev; i++)
 903                                 putchar('-');
 904                         putchar('\n');
 905                 }
 906         }
 907         if (extra < 0)
 908                 exit(0);
 909
 910         /* Sort topologically */
 911         sort_in_topological_order(&seen, lifo);
 912
 913         /* Give names to commits */
 914         if (!sha1_name && !no_name)
 915                 name_commits(seen, rev, ref_name, num_rev);
 916
 917         all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 918         all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 919
 920         while (seen) {
 921                 struct commit *commit = pop_one_commit(&seen);
 922                 int this_flag = commit->object.flags;
 923                 int is_merge_point = ((this_flag & all_revs) == all_revs);
 924
 925                 shown_merge_point |= is_merge_point;
 926
 927                 if (1 < num_rev) {
 928                         int is_merge = !!(commit->parents &&
 929                                           commit->parents->next);
 930                         if (topics &&
 931                             !is_merge_point &&
 932                             (this_flag & (1u << REV_SHIFT)))
 933                                 continue;
 934                         if (dense && is_merge &&
 935                             omit_in_dense(commit, rev, num_rev))
 936                                 continue;
 937                         for (i = 0; i < num_rev; i++) {
 938                                 int mark;
 939                                 if (!(this_flag & (1u << (i + REV_SHIFT))))
 940                                         mark = ' ';
 941                                 else if (is_merge)
 942                                         mark = '-';
 943                                 else if (i == head_at)
 944                                         mark = '*';
 945                                 else
 946                                         mark = '+';
 947                                 printf("%s%c%s",
 948                                        get_color_code(i % COLUMN_COLORS_MAX),
 949                                        mark, get_color_reset_code());
 950                         }
 951                         putchar(' ');
 952                 }
 953                 show_one_commit(commit, no_name);
 954
 955                 if (shown_merge_point && --extra < 0)
 956                         break;
 957         }
 958         return 0;
 959 }