builtin/show-branch.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "environment.h"
   4 #include "gettext.h"
   5 #include "hex.h"
   6 #include "pretty.h"
   7 #include "refs.h"
   8 #include "builtin.h"
   9 #include "color.h"
  10 #include "strvec.h"
  11 #include "parse-options.h"
  12 #include "dir.h"
  13 #include "commit-slab.h"
  14 #include "date.h"
  15
  16 static const char* show_branch_usage[] = {
  17     N_("git show-branch [-a | --all] [-r | --remotes] [--topo-order | --date-order]\n"
  18        "                [--current] [--color[=<when>] | --no-color] [--sparse]\n"
  19        "                [--more=<n> | --list | --independent | --merge-base]\n"
  20        "                [--no-name | --sha1-name] [--topics]\n"
  21        "                [(<rev> | <glob>)...]"),
  22     N_("git show-branch (-g | --reflog)[=<n>[,<base>]] [--list] [<ref>]"),
  23     NULL
  24 };
  25
  26 static int showbranch_use_color = -1;
  27
  28 static struct strvec default_args = STRVEC_INIT;
  29
  30 /*
  31  * TODO: convert this use of commit->object.flags to commit-slab
  32  * instead to store a pointer to ref name directly. Then use the same
  33  * UNINTERESTING definition from revision.h here.
  34  */
  35 #define UNINTERESTING   01
  36
  37 #define REV_SHIFT        2
  38 #define MAX_REVS        (FLAG_BITS - REV_SHIFT) /* should not exceed bits_per_int - REV_SHIFT */
  39
  40 #define DEFAULT_REFLOG  4
  41
  42 static const char *get_color_code(int idx)
  43 {
  44         if (want_color(showbranch_use_color))
  45                 return column_colors_ansi[idx % column_colors_ansi_max];
  46         return "";
  47 }
  48
  49 static const char *get_color_reset_code(void)
  50 {
  51         if (want_color(showbranch_use_color))
  52                 return GIT_COLOR_RESET;
  53         return "";
  54 }
  55
  56 static struct commit *interesting(struct commit_list *list)
  57 {
  58         while (list) {
  59                 struct commit *commit = list->item;
  60                 list = list->next;
  61                 if (commit->object.flags & UNINTERESTING)
  62                         continue;
  63                 return commit;
  64         }
  65         return NULL;
  66 }
  67
  68 struct commit_name {
  69         const char *head_name; /* which head's ancestor? */
  70         int generation; /* how many parents away from head_name */
  71 };
  72
  73 define_commit_slab(commit_name_slab, struct commit_name *);
  74 static struct commit_name_slab name_slab;
  75
  76 static struct commit_name *commit_to_name(struct commit *commit)
  77 {
  78         return *commit_name_slab_at(&name_slab, commit);
  79 }
  80
  81
  82 /* Name the commit as nth generation ancestor of head_name;
  83  * we count only the first-parent relationship for naming purposes.
  84  */
  85 static void name_commit(struct commit *commit, const char *head_name, int nth)
  86 {
  87         struct commit_name *name;
  88
  89         name = *commit_name_slab_at(&name_slab, commit);
  90         if (!name) {
  91                 name = xmalloc(sizeof(*name));
  92                 *commit_name_slab_at(&name_slab, commit) = name;
  93         }
  94         name->head_name = head_name;
  95         name->generation = nth;
  96 }
  97
  98 /* Parent is the first parent of the commit.  We may name it
  99  * as (n+1)th generation ancestor of the same head_name as
 100  * commit is nth generation ancestor of, if that generation
 101  * number is better than the name it already has.
 102  */
 103 static void name_parent(struct commit *commit, struct commit *parent)
 104 {
 105         struct commit_name *commit_name = commit_to_name(commit);
 106         struct commit_name *parent_name = commit_to_name(parent);
 107         if (!commit_name)
 108                 return;
 109         if (!parent_name ||
 110             commit_name->generation + 1 < parent_name->generation)
 111                 name_commit(parent, commit_name->head_name,
 112                             commit_name->generation + 1);
 113 }
 114
 115 static int name_first_parent_chain(struct commit *c)
 116 {
 117         int i = 0;
 118         while (c) {
 119                 struct commit *p;
 120                 if (!commit_to_name(c))
 121                         break;
 122                 if (!c->parents)
 123                         break;
 124                 p = c->parents->item;
 125                 if (!commit_to_name(p)) {
 126                         name_parent(c, p);
 127                         i++;
 128                 }
 129                 else
 130                         break;
 131                 c = p;
 132         }
 133         return i;
 134 }
 135
 136 static void name_commits(struct commit_list *list,
 137                          struct commit **rev,
 138                          char **ref_name,
 139                          int num_rev)
 140 {
 141         struct commit_list *cl;
 142         struct commit *c;
 143         int i;
 144
 145         /* First give names to the given heads */
 146         for (cl = list; cl; cl = cl->next) {
 147                 c = cl->item;
 148                 if (commit_to_name(c))
 149                         continue;
 150                 for (i = 0; i < num_rev; i++) {
 151                         if (rev[i] == c) {
 152                                 name_commit(c, ref_name[i], 0);
 153                                 break;
 154                         }
 155                 }
 156         }
 157
 158         /* Then commits on the first parent ancestry chain */
 159         do {
 160                 i = 0;
 161                 for (cl = list; cl; cl = cl->next) {
 162                         i += name_first_parent_chain(cl->item);
 163                 }
 164         } while (i);
 165
 166         /* Finally, any unnamed commits */
 167         do {
 168                 i = 0;
 169                 for (cl = list; cl; cl = cl->next) {
 170                         struct commit_list *parents;
 171                         struct commit_name *n;
 172                         int nth;
 173                         c = cl->item;
 174                         if (!commit_to_name(c))
 175                                 continue;
 176                         n = commit_to_name(c);
 177                         parents = c->parents;
 178                         nth = 0;
 179                         while (parents) {
 180                                 struct commit *p = parents->item;
 181                                 struct strbuf newname = STRBUF_INIT;
 182                                 parents = parents->next;
 183                                 nth++;
 184                                 if (commit_to_name(p))
 185                                         continue;
 186                                 switch (n->generation) {
 187                                 case 0:
 188                                         strbuf_addstr(&newname, n->head_name);
 189                                         break;
 190                                 case 1:
 191                                         strbuf_addf(&newname, "%s^", n->head_name);
 192                                         break;
 193                                 default:
 194                                         strbuf_addf(&newname, "%s~%d",
 195                                                     n->head_name, n->generation);
 196                                         break;
 197                                 }
 198                                 if (nth == 1)
 199                                         strbuf_addch(&newname, '^');
 200                                 else
 201                                         strbuf_addf(&newname, "^%d", nth);
 202                                 name_commit(p, strbuf_detach(&newname, NULL), 0);
 203                                 i++;
 204                                 name_first_parent_chain(p);
 205                         }
 206                 }
 207         } while (i);
 208 }
 209
 210 static int mark_seen(struct commit *commit, struct commit_list **seen_p)
 211 {
 212         if (!commit->object.flags) {
 213                 commit_list_insert(commit, seen_p);
 214                 return 1;
 215         }
 216         return 0;
 217 }
 218
 219 static void join_revs(struct commit_list **list_p,
 220                       struct commit_list **seen_p,
 221                       int num_rev, int extra)
 222 {
 223         int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 224         int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 225
 226         while (*list_p) {
 227                 struct commit_list *parents;
 228                 int still_interesting = !!interesting(*list_p);
 229                 struct commit *commit = pop_commit(list_p);
 230                 int flags = commit->object.flags & all_mask;
 231
 232                 if (!still_interesting && extra <= 0)
 233                         break;
 234
 235                 mark_seen(commit, seen_p);
 236                 if ((flags & all_revs) == all_revs)
 237                         flags |= UNINTERESTING;
 238                 parents = commit->parents;
 239
 240                 while (parents) {
 241                         struct commit *p = parents->item;
 242                         int this_flag = p->object.flags;
 243                         parents = parents->next;
 244                         if ((this_flag & flags) == flags)
 245                                 continue;
 246                         repo_parse_commit(the_repository, p);
 247                         if (mark_seen(p, seen_p) && !still_interesting)
 248                                 extra--;
 249                         p->object.flags |= flags;
 250                         commit_list_insert_by_date(p, list_p);
 251                 }
 252         }
 253
 254         /*
 255          * Postprocess to complete well-poisoning.
 256          *
 257          * At this point we have all the commits we have seen in
 258          * seen_p list.  Mark anything that can be reached from
 259          * uninteresting commits not interesting.
 260          */
 261         for (;;) {
 262                 int changed = 0;
 263                 struct commit_list *s;
 264                 for (s = *seen_p; s; s = s->next) {
 265                         struct commit *c = s->item;
 266                         struct commit_list *parents;
 267
 268                         if (((c->object.flags & all_revs) != all_revs) &&
 269                             !(c->object.flags & UNINTERESTING))
 270                                 continue;
 271
 272                         /* The current commit is either a merge base or
 273                          * already uninteresting one.  Mark its parents
 274                          * as uninteresting commits _only_ if they are
 275                          * already parsed.  No reason to find new ones
 276                          * here.
 277                          */
 278                         parents = c->parents;
 279                         while (parents) {
 280                                 struct commit *p = parents->item;
 281                                 parents = parents->next;
 282                                 if (!(p->object.flags & UNINTERESTING)) {
 283                                         p->object.flags |= UNINTERESTING;
 284                                         changed = 1;
 285                                 }
 286                         }
 287                 }
 288                 if (!changed)
 289                         break;
 290         }
 291 }
 292
 293 static void show_one_commit(struct commit *commit, int no_name)
 294 {
 295         struct strbuf pretty = STRBUF_INIT;
 296         const char *pretty_str = "(unavailable)";
 297         struct commit_name *name = commit_to_name(commit);
 298
 299         if (commit->object.parsed) {
 300                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &pretty);
 301                 pretty_str = pretty.buf;
 302         }
 303         skip_prefix(pretty_str, "[PATCH] ", &pretty_str);
 304
 305         if (!no_name) {
 306                 if (name && name->head_name) {
 307                         printf("[%s", name->head_name);
 308                         if (name->generation) {
 309                                 if (name->generation == 1)
 310                                         printf("^");
 311                                 else
 312                                         printf("~%d", name->generation);
 313                         }
 314                         printf("] ");
 315                 }
 316                 else
 317                         printf("[%s] ",
 318                                repo_find_unique_abbrev(the_repository, &commit->object.oid,
 319                                                        DEFAULT_ABBREV));
 320         }
 321         puts(pretty_str);
 322         strbuf_release(&pretty);
 323 }
 324
 325 static char *ref_name[MAX_REVS + 1];
 326 static int ref_name_cnt;
 327
 328 static const char *find_digit_prefix(const char *s, int *v)
 329 {
 330         const char *p;
 331         int ver;
 332         char ch;
 333
 334         for (p = s, ver = 0;
 335              '0' <= (ch = *p) && ch <= '9';
 336              p++)
 337                 ver = ver * 10 + ch - '0';
 338         *v = ver;
 339         return p;
 340 }
 341
 342
 343 static int version_cmp(const char *a, const char *b)
 344 {
 345         while (1) {
 346                 int va, vb;
 347
 348                 a = find_digit_prefix(a, &va);
 349                 b = find_digit_prefix(b, &vb);
 350                 if (va != vb)
 351                         return va - vb;
 352
 353                 while (1) {
 354                         int ca = *a;
 355                         int cb = *b;
 356                         if ('0' <= ca && ca <= '9')
 357                                 ca = 0;
 358                         if ('0' <= cb && cb <= '9')
 359                                 cb = 0;
 360                         if (ca != cb)
 361                                 return ca - cb;
 362                         if (!ca)
 363                                 break;
 364                         a++;
 365                         b++;
 366                 }
 367                 if (!*a && !*b)
 368                         return 0;
 369         }
 370 }
 371
 372 static int compare_ref_name(const void *a_, const void *b_)
 373 {
 374         const char * const*a = a_, * const*b = b_;
 375         return version_cmp(*a, *b);
 376 }
 377
 378 static void sort_ref_range(int bottom, int top)
 379 {
 380         QSORT(ref_name + bottom, top - bottom, compare_ref_name);
 381 }
 382
 383 static int append_ref(const char *refname, const struct object_id *oid,
 384                       int allow_dups)
 385 {
 386         struct commit *commit = lookup_commit_reference_gently(the_repository,
 387                                                                oid, 1);
 388         int i;
 389
 390         if (!commit)
 391                 return 0;
 392
 393         if (!allow_dups) {
 394                 /* Avoid adding the same thing twice */
 395                 for (i = 0; i < ref_name_cnt; i++)
 396                         if (!strcmp(refname, ref_name[i]))
 397                                 return 0;
 398         }
 399         if (MAX_REVS <= ref_name_cnt) {
 400                 warning(Q_("ignoring %s; cannot handle more than %d ref",
 401                            "ignoring %s; cannot handle more than %d refs",
 402                            MAX_REVS), refname, MAX_REVS);
 403                 return 0;
 404         }
 405         ref_name[ref_name_cnt++] = xstrdup(refname);
 406         ref_name[ref_name_cnt] = NULL;
 407         return 0;
 408 }
 409
 410 static int append_head_ref(const char *refname, const struct object_id *oid,
 411                            int flag UNUSED, void *cb_data UNUSED)
 412 {
 413         struct object_id tmp;
 414         int ofs = 11;
 415         if (!starts_with(refname, "refs/heads/"))
 416                 return 0;
 417         /* If both heads/foo and tags/foo exists, get_sha1 would
 418          * get confused.
 419          */
 420         if (repo_get_oid(the_repository, refname + ofs, &tmp) || !oideq(&tmp, oid))
 421                 ofs = 5;
 422         return append_ref(refname + ofs, oid, 0);
 423 }
 424
 425 static int append_remote_ref(const char *refname, const struct object_id *oid,
 426                              int flag UNUSED, void *cb_data UNUSED)
 427 {
 428         struct object_id tmp;
 429         int ofs = 13;
 430         if (!starts_with(refname, "refs/remotes/"))
 431                 return 0;
 432         /* If both heads/foo and tags/foo exists, get_sha1 would
 433          * get confused.
 434          */
 435         if (repo_get_oid(the_repository, refname + ofs, &tmp) || !oideq(&tmp, oid))
 436                 ofs = 5;
 437         return append_ref(refname + ofs, oid, 0);
 438 }
 439
 440 static int append_tag_ref(const char *refname, const struct object_id *oid,
 441                           int flag UNUSED, void *cb_data UNUSED)
 442 {
 443         if (!starts_with(refname, "refs/tags/"))
 444                 return 0;
 445         return append_ref(refname + 5, oid, 0);
 446 }
 447
 448 static const char *match_ref_pattern = NULL;
 449 static int match_ref_slash = 0;
 450
 451 static int append_matching_ref(const char *refname, const struct object_id *oid,
 452                                int flag, void *cb_data)
 453 {
 454         /* we want to allow pattern hold/<asterisk> to show all
 455          * branches under refs/heads/hold/, and v0.99.9? to show
 456          * refs/tags/v0.99.9a and friends.
 457          */
 458         const char *tail;
 459         int slash = count_slashes(refname);
 460         for (tail = refname; *tail && match_ref_slash < slash; )
 461                 if (*tail++ == '/')
 462                         slash--;
 463         if (!*tail)
 464                 return 0;
 465         if (wildmatch(match_ref_pattern, tail, 0))
 466                 return 0;
 467         if (starts_with(refname, "refs/heads/"))
 468                 return append_head_ref(refname, oid, flag, cb_data);
 469         if (starts_with(refname, "refs/tags/"))
 470                 return append_tag_ref(refname, oid, flag, cb_data);
 471         return append_ref(refname, oid, 0);
 472 }
 473
 474 static void snarf_refs(int head, int remotes)
 475 {
 476         if (head) {
 477                 int orig_cnt = ref_name_cnt;
 478
 479                 for_each_ref(append_head_ref, NULL);
 480                 sort_ref_range(orig_cnt, ref_name_cnt);
 481         }
 482         if (remotes) {
 483                 int orig_cnt = ref_name_cnt;
 484
 485                 for_each_ref(append_remote_ref, NULL);
 486                 sort_ref_range(orig_cnt, ref_name_cnt);
 487         }
 488 }
 489
 490 static int rev_is_head(const char *head, const char *name)
 491 {
 492         if (!head)
 493                 return 0;
 494         skip_prefix(head, "refs/heads/", &head);
 495         if (!skip_prefix(name, "refs/heads/", &name))
 496                 skip_prefix(name, "heads/", &name);
 497         return !strcmp(head, name);
 498 }
 499
 500 static int show_merge_base(struct commit_list *seen, int num_rev)
 501 {
 502         int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 503         int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 504         int exit_status = 1;
 505
 506         while (seen) {
 507                 struct commit *commit = pop_commit(&seen);
 508                 int flags = commit->object.flags & all_mask;
 509                 if (!(flags & UNINTERESTING) &&
 510                     ((flags & all_revs) == all_revs)) {
 511                         puts(oid_to_hex(&commit->object.oid));
 512                         exit_status = 0;
 513                         commit->object.flags |= UNINTERESTING;
 514                 }
 515         }
 516         return exit_status;
 517 }
 518
 519 static int show_independent(struct commit **rev,
 520                             int num_rev,
 521                             unsigned int *rev_mask)
 522 {
 523         int i;
 524
 525         for (i = 0; i < num_rev; i++) {
 526                 struct commit *commit = rev[i];
 527                 unsigned int flag = rev_mask[i];
 528
 529                 if (commit->object.flags == flag)
 530                         puts(oid_to_hex(&commit->object.oid));
 531                 commit->object.flags |= UNINTERESTING;
 532         }
 533         return 0;
 534 }
 535
 536 static void append_one_rev(const char *av)
 537 {
 538         struct object_id revkey;
 539         if (!repo_get_oid(the_repository, av, &revkey)) {
 540                 append_ref(av, &revkey, 0);
 541                 return;
 542         }
 543         if (strpbrk(av, "*?[")) {
 544                 /* glob style match */
 545                 int saved_matches = ref_name_cnt;
 546
 547                 match_ref_pattern = av;
 548                 match_ref_slash = count_slashes(av);
 549                 for_each_ref(append_matching_ref, NULL);
 550                 if (saved_matches == ref_name_cnt &&
 551                     ref_name_cnt < MAX_REVS)
 552                         error(_("no matching refs with %s"), av);
 553                 sort_ref_range(saved_matches, ref_name_cnt);
 554                 return;
 555         }
 556         die("bad sha1 reference %s", av);
 557 }
 558
 559 static int git_show_branch_config(const char *var, const char *value, void *cb)
 560 {
 561         if (!strcmp(var, "showbranch.default")) {
 562                 if (!value)
 563                         return config_error_nonbool(var);
 564                 /*
 565                  * default_arg is now passed to parse_options(), so we need to
 566                  * mimic the real argv a bit better.
 567                  */
 568                 if (!default_args.nr)
 569                         strvec_push(&default_args, "show-branch");
 570                 strvec_push(&default_args, value);
 571                 return 0;
 572         }
 573
 574         if (!strcmp(var, "color.showbranch")) {
 575                 showbranch_use_color = git_config_colorbool(var, value);
 576                 return 0;
 577         }
 578
 579         return git_color_default_config(var, value, cb);
 580 }
 581
 582 static int omit_in_dense(struct commit *commit, struct commit **rev, int n)
 583 {
 584         /* If the commit is tip of the named branches, do not
 585          * omit it.
 586          * Otherwise, if it is a merge that is reachable from only one
 587          * tip, it is not that interesting.
 588          */
 589         int i, flag, count;
 590         for (i = 0; i < n; i++)
 591                 if (rev[i] == commit)
 592                         return 0;
 593         flag = commit->object.flags;
 594         for (i = count = 0; i < n; i++) {
 595                 if (flag & (1u << (i + REV_SHIFT)))
 596                         count++;
 597         }
 598         if (count == 1)
 599                 return 1;
 600         return 0;
 601 }
 602
 603 static int reflog = 0;
 604
 605 static int parse_reflog_param(const struct option *opt, const char *arg,
 606                               int unset)
 607 {
 608         char *ep;
 609         const char **base = (const char **)opt->value;
 610         BUG_ON_OPT_NEG(unset);
 611         if (!arg)
 612                 arg = "";
 613         reflog = strtoul(arg, &ep, 10);
 614         if (*ep == ',')
 615                 *base = ep + 1;
 616         else if (*ep)
 617                 return error("unrecognized reflog param '%s'", arg);
 618         else
 619                 *base = NULL;
 620         if (reflog <= 0)
 621                 reflog = DEFAULT_REFLOG;
 622         return 0;
 623 }
 624
 625 int cmd_show_branch(int ac, const char **av, const char *prefix)
 626 {
 627         struct commit *rev[MAX_REVS], *commit;
 628         char *reflog_msg[MAX_REVS];
 629         struct commit_list *list = NULL, *seen = NULL;
 630         unsigned int rev_mask[MAX_REVS];
 631         int num_rev, i, extra = 0;
 632         int all_heads = 0, all_remotes = 0;
 633         int all_mask, all_revs;
 634         enum rev_sort_order sort_order = REV_SORT_IN_GRAPH_ORDER;
 635         char *head;
 636         struct object_id head_oid;
 637         int merge_base = 0;
 638         int independent = 0;
 639         int no_name = 0;
 640         int sha1_name = 0;
 641         int shown_merge_point = 0;
 642         int with_current_branch = 0;
 643         int head_at = -1;
 644         int topics = 0;
 645         int dense = 1;
 646         const char *reflog_base = NULL;
 647         struct option builtin_show_branch_options[] = {
 648                 OPT_BOOL('a', "all", &all_heads,
 649                          N_("show remote-tracking and local branches")),
 650                 OPT_BOOL('r', "remotes", &all_remotes,
 651                          N_("show remote-tracking branches")),
 652                 OPT__COLOR(&showbranch_use_color,
 653                             N_("color '*!+-' corresponding to the branch")),
 654                 { OPTION_INTEGER, 0, "more", &extra, N_("n"),
 655                             N_("show <n> more commits after the common ancestor"),
 656                             PARSE_OPT_OPTARG, NULL, (intptr_t)1 },
 657                 OPT_SET_INT(0, "list", &extra, N_("synonym to more=-1"), -1),
 658                 OPT_BOOL(0, "no-name", &no_name, N_("suppress naming strings")),
 659                 OPT_BOOL(0, "current", &with_current_branch,
 660                          N_("include the current branch")),
 661                 OPT_BOOL(0, "sha1-name", &sha1_name,
 662                          N_("name commits with their object names")),
 663                 OPT_BOOL(0, "merge-base", &merge_base,
 664                          N_("show possible merge bases")),
 665                 OPT_BOOL(0, "independent", &independent,
 666                             N_("show refs unreachable from any other ref")),
 667                 OPT_SET_INT(0, "topo-order", &sort_order,
 668                             N_("show commits in topological order"),
 669                             REV_SORT_IN_GRAPH_ORDER),
 670                 OPT_BOOL(0, "topics", &topics,
 671                          N_("show only commits not on the first branch")),
 672                 OPT_SET_INT(0, "sparse", &dense,
 673                             N_("show merges reachable from only one tip"), 0),
 674                 OPT_SET_INT(0, "date-order", &sort_order,
 675                             N_("topologically sort, maintaining date order "
 676                                "where possible"),
 677                             REV_SORT_BY_COMMIT_DATE),
 678                 OPT_CALLBACK_F('g', "reflog", &reflog_base, N_("<n>[,<base>]"),
 679                             N_("show <n> most recent ref-log entries starting at "
 680                                "base"),
 681                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
 682                             parse_reflog_param),
 683                 OPT_END()
 684         };
 685
 686         init_commit_name_slab(&name_slab);
 687
 688         git_config(git_show_branch_config, NULL);
 689
 690         /* If nothing is specified, try the default first */
 691         if (ac == 1 && default_args.nr) {
 692                 ac = default_args.nr;
 693                 av = default_args.v;
 694         }
 695
 696         ac = parse_options(ac, av, prefix, builtin_show_branch_options,
 697                            show_branch_usage, PARSE_OPT_STOP_AT_NON_OPTION);
 698         if (all_heads)
 699                 all_remotes = 1;
 700
 701         if (extra || reflog) {
 702                 /* "listing" mode is incompatible with
 703                  * independent nor merge-base modes.
 704                  */
 705                 if (independent || merge_base)
 706                         usage_with_options(show_branch_usage,
 707                                            builtin_show_branch_options);
 708                 if (reflog && ((0 < extra) || all_heads || all_remotes))
 709                         /*
 710                          * Asking for --more in reflog mode does not
 711                          * make sense.  --list is Ok.
 712                          *
 713                          * Also --all and --remotes do not make sense either.
 714                          */
 715                         die(_("options '%s' and '%s' cannot be used together"), "--reflog",
 716                                 "--all/--remotes/--independent/--merge-base");
 717         }
 718
 719         if (with_current_branch && reflog)
 720                 die(_("options '%s' and '%s' cannot be used together"),
 721                     "--reflog", "--current");
 722
 723         /* If nothing is specified, show all branches by default */
 724         if (ac <= topics && all_heads + all_remotes == 0)
 725                 all_heads = 1;
 726
 727         if (reflog) {
 728                 struct object_id oid;
 729                 char *ref;
 730                 int base = 0;
 731                 unsigned int flags = 0;
 732
 733                 if (ac == 0) {
 734                         static const char *fake_av[2];
 735
 736                         fake_av[0] = resolve_refdup("HEAD",
 737                                                     RESOLVE_REF_READING, &oid,
 738                                                     NULL);
 739                         fake_av[1] = NULL;
 740                         av = fake_av;
 741                         ac = 1;
 742                         if (!*av)
 743                                 die(_("no branches given, and HEAD is not valid"));
 744                 }
 745                 if (ac != 1)
 746                         die(_("--reflog option needs one branch name"));
 747
 748                 if (MAX_REVS < reflog)
 749                         die(Q_("only %d entry can be shown at one time.",
 750                                "only %d entries can be shown at one time.",
 751                                MAX_REVS), MAX_REVS);
 752                 if (!repo_dwim_ref(the_repository, *av, strlen(*av), &oid,
 753                                    &ref, 0))
 754                         die(_("no such ref %s"), *av);
 755
 756                 /* Has the base been specified? */
 757                 if (reflog_base) {
 758                         char *ep;
 759                         base = strtoul(reflog_base, &ep, 10);
 760                         if (*ep) {
 761                                 /* Ah, that is a date spec... */
 762                                 timestamp_t at;
 763                                 at = approxidate(reflog_base);
 764                                 read_ref_at(get_main_ref_store(the_repository),
 765                                             ref, flags, at, -1, &oid, NULL,
 766                                             NULL, NULL, &base);
 767                         }
 768                 }
 769
 770                 for (i = 0; i < reflog; i++) {
 771                         char *logmsg;
 772                         char *nth_desc;
 773                         const char *msg;
 774                         char *end;
 775                         timestamp_t timestamp;
 776                         int tz;
 777
 778                         if (read_ref_at(get_main_ref_store(the_repository),
 779                                         ref, flags, 0, base + i, &oid, &logmsg,
 780                                         &timestamp, &tz, NULL)) {
 781                                 reflog = i;
 782                                 break;
 783                         }
 784
 785                         end = strchr(logmsg, '\n');
 786                         if (end)
 787                                 *end = '\0';
 788
 789                         msg = (*logmsg == '\0') ? "(none)" : logmsg;
 790                         reflog_msg[i] = xstrfmt("(%s) %s",
 791                                                 show_date(timestamp, tz,
 792                                                           DATE_MODE(RELATIVE)),
 793                                                 msg);
 794                         free(logmsg);
 795
 796                         nth_desc = xstrfmt("%s@{%d}", *av, base+i);
 797                         append_ref(nth_desc, &oid, 1);
 798                         free(nth_desc);
 799                 }
 800                 free(ref);
 801         }
 802         else {
 803                 while (0 < ac) {
 804                         append_one_rev(*av);
 805                         ac--; av++;
 806                 }
 807                 if (all_heads + all_remotes)
 808                         snarf_refs(all_heads, all_remotes);
 809         }
 810
 811         head = resolve_refdup("HEAD", RESOLVE_REF_READING,
 812                               &head_oid, NULL);
 813
 814         if (with_current_branch && head) {
 815                 int has_head = 0;
 816                 for (i = 0; !has_head && i < ref_name_cnt; i++) {
 817                         /* We are only interested in adding the branch
 818                          * HEAD points at.
 819                          */
 820                         if (rev_is_head(head, ref_name[i]))
 821                                 has_head++;
 822                 }
 823                 if (!has_head) {
 824                         const char *name = head;
 825                         skip_prefix(name, "refs/heads/", &name);
 826                         append_one_rev(name);
 827                 }
 828         }
 829
 830         if (!ref_name_cnt) {
 831                 fprintf(stderr, "No revs to be shown.\n");
 832                 exit(0);
 833         }
 834
 835         for (num_rev = 0; ref_name[num_rev]; num_rev++) {
 836                 struct object_id revkey;
 837                 unsigned int flag = 1u << (num_rev + REV_SHIFT);
 838
 839                 if (MAX_REVS <= num_rev)
 840                         die(Q_("cannot handle more than %d rev.",
 841                                "cannot handle more than %d revs.",
 842                                MAX_REVS), MAX_REVS);
 843                 if (repo_get_oid(the_repository, ref_name[num_rev], &revkey))
 844                         die(_("'%s' is not a valid ref."), ref_name[num_rev]);
 845                 commit = lookup_commit_reference(the_repository, &revkey);
 846                 if (!commit)
 847                         die(_("cannot find commit %s (%s)"),
 848                             ref_name[num_rev], oid_to_hex(&revkey));
 849                 repo_parse_commit(the_repository, commit);
 850                 mark_seen(commit, &seen);
 851
 852                 /* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
 853                  * and so on.  REV_SHIFT bits from bit 0 are used for
 854                  * internal bookkeeping.
 855                  */
 856                 commit->object.flags |= flag;
 857                 if (commit->object.flags == flag)
 858                         commit_list_insert_by_date(commit, &list);
 859                 rev[num_rev] = commit;
 860         }
 861         for (i = 0; i < num_rev; i++)
 862                 rev_mask[i] = rev[i]->object.flags;
 863
 864         if (0 <= extra)
 865                 join_revs(&list, &seen, num_rev, extra);
 866
 867         commit_list_sort_by_date(&seen);
 868
 869         if (merge_base)
 870                 return show_merge_base(seen, num_rev);
 871
 872         if (independent)
 873                 return show_independent(rev, num_rev, rev_mask);
 874
 875         /* Show list; --more=-1 means list-only */
 876         if (1 < num_rev || extra < 0) {
 877                 for (i = 0; i < num_rev; i++) {
 878                         int j;
 879                         int is_head = rev_is_head(head, ref_name[i]) &&
 880                                       oideq(&head_oid, &rev[i]->object.oid);
 881                         if (extra < 0)
 882                                 printf("%c [%s] ",
 883                                        is_head ? '*' : ' ', ref_name[i]);
 884                         else {
 885                                 for (j = 0; j < i; j++)
 886                                         putchar(' ');
 887                                 printf("%s%c%s [%s] ",
 888                                        get_color_code(i),
 889                                        is_head ? '*' : '!',
 890                                        get_color_reset_code(), ref_name[i]);
 891                         }
 892
 893                         if (!reflog) {
 894                                 /* header lines never need name */
 895                                 show_one_commit(rev[i], 1);
 896                         }
 897                         else
 898                                 puts(reflog_msg[i]);
 899
 900                         if (is_head)
 901                                 head_at = i;
 902                 }
 903                 if (0 <= extra) {
 904                         for (i = 0; i < num_rev; i++)
 905                                 putchar('-');
 906                         putchar('\n');
 907                 }
 908         }
 909         if (extra < 0)
 910                 exit(0);
 911
 912         /* Sort topologically */
 913         sort_in_topological_order(&seen, sort_order);
 914
 915         /* Give names to commits */
 916         if (!sha1_name && !no_name)
 917                 name_commits(seen, rev, ref_name, num_rev);
 918
 919         all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 920         all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 921
 922         while (seen) {
 923                 struct commit *commit = pop_commit(&seen);
 924                 int this_flag = commit->object.flags;
 925                 int is_merge_point = ((this_flag & all_revs) == all_revs);
 926
 927                 shown_merge_point |= is_merge_point;
 928
 929                 if (1 < num_rev) {
 930                         int is_merge = !!(commit->parents &&
 931                                           commit->parents->next);
 932                         if (topics &&
 933                             !is_merge_point &&
 934                             (this_flag & (1u << REV_SHIFT)))
 935                                 continue;
 936                         if (dense && is_merge &&
 937                             omit_in_dense(commit, rev, num_rev))
 938                                 continue;
 939                         for (i = 0; i < num_rev; i++) {
 940                                 int mark;
 941                                 if (!(this_flag & (1u << (i + REV_SHIFT))))
 942                                         mark = ' ';
 943                                 else if (is_merge)
 944                                         mark = '-';
 945                                 else if (i == head_at)
 946                                         mark = '*';
 947                                 else
 948                                         mark = '+';
 949                                 if (mark == ' ')
 950                                         putchar(mark);
 951                                 else
 952                                         printf("%s%c%s",
 953                                                get_color_code(i),
 954                                                mark, get_color_reset_code());
 955                         }
 956                         putchar(' ');
 957                 }
 958                 show_one_commit(commit, no_name);
 959
 960                 if (shown_merge_point && --extra < 0)
 961                         break;
 962         }
 963         free(head);
 964         return 0;
 965 }