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

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