Andrew's git / gitweb.git / builtin-show-branch.c
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builtin-show-branch.con commit show-branch --reflog: show the reflog message at the top. (76a44c5)
   1#include "cache.h"
   2#include "commit.h"
   3#include "refs.h"
   4#include "builtin.h"
   5
   6static const char show_branch_usage[] =
   7"git-show-branch [--sparse] [--current] [--all] [--remotes] [--topo-order] [--more=count | --list | --independent | --merge-base ] [--topics] [<refs>...] | --reflog[=n] <branch>";
   8
   9static int default_num;
  10static int default_alloc;
  11static const char **default_arg;
  12
  13#define UNINTERESTING   01
  14
  15#define REV_SHIFT        2
  16#define MAX_REVS        (FLAG_BITS - REV_SHIFT) /* should not exceed bits_per_int - REV_SHIFT */
  17
  18#define DEFAULT_REFLOG  4
  19
  20static struct commit *interesting(struct commit_list *list)
  21{
  22        while (list) {
  23                struct commit *commit = list->item;
  24                list = list->next;
  25                if (commit->object.flags & UNINTERESTING)
  26                        continue;
  27                return commit;
  28        }
  29        return NULL;
  30}
  31
  32static struct commit *pop_one_commit(struct commit_list **list_p)
  33{
  34        struct commit *commit;
  35        struct commit_list *list;
  36        list = *list_p;
  37        commit = list->item;
  38        *list_p = list->next;
  39        free(list);
  40        return commit;
  41}
  42
  43struct commit_name {
  44        const char *head_name; /* which head's ancestor? */
  45        int generation; /* how many parents away from head_name */
  46};
  47
  48/* Name the commit as nth generation ancestor of head_name;
  49 * we count only the first-parent relationship for naming purposes.
  50 */
  51static void name_commit(struct commit *commit, const char *head_name, int nth)
  52{
  53        struct commit_name *name;
  54        if (!commit->util)
  55                commit->util = xmalloc(sizeof(struct commit_name));
  56        name = commit->util;
  57        name->head_name = head_name;
  58        name->generation = nth;
  59}
  60
  61/* Parent is the first parent of the commit.  We may name it
  62 * as (n+1)th generation ancestor of the same head_name as
  63 * commit is nth generation ancestor of, if that generation
  64 * number is better than the name it already has.
  65 */
  66static void name_parent(struct commit *commit, struct commit *parent)
  67{
  68        struct commit_name *commit_name = commit->util;
  69        struct commit_name *parent_name = parent->util;
  70        if (!commit_name)
  71                return;
  72        if (!parent_name ||
  73            commit_name->generation + 1 < parent_name->generation)
  74                name_commit(parent, commit_name->head_name,
  75                            commit_name->generation + 1);
  76}
  77
  78static int name_first_parent_chain(struct commit *c)
  79{
  80        int i = 0;
  81        while (c) {
  82                struct commit *p;
  83                if (!c->util)
  84                        break;
  85                if (!c->parents)
  86                        break;
  87                p = c->parents->item;
  88                if (!p->util) {
  89                        name_parent(c, p);
  90                        i++;
  91                }
  92                else
  93                        break;
  94                c = p;
  95        }
  96        return i;
  97}
  98
  99static void name_commits(struct commit_list *list,
 100                         struct commit **rev,
 101                         char **ref_name,
 102                         int num_rev)
 103{
 104        struct commit_list *cl;
 105        struct commit *c;
 106        int i;
 107
 108        /* First give names to the given heads */
 109        for (cl = list; cl; cl = cl->next) {
 110                c = cl->item;
 111                if (c->util)
 112                        continue;
 113                for (i = 0; i < num_rev; i++) {
 114                        if (rev[i] == c) {
 115                                name_commit(c, ref_name[i], 0);
 116                                break;
 117                        }
 118                }
 119        }
 120
 121        /* Then commits on the first parent ancestry chain */
 122        do {
 123                i = 0;
 124                for (cl = list; cl; cl = cl->next) {
 125                        i += name_first_parent_chain(cl->item);
 126                }
 127        } while (i);
 128
 129        /* Finally, any unnamed commits */
 130        do {
 131                i = 0;
 132                for (cl = list; cl; cl = cl->next) {
 133                        struct commit_list *parents;
 134                        struct commit_name *n;
 135                        int nth;
 136                        c = cl->item;
 137                        if (!c->util)
 138                                continue;
 139                        n = c->util;
 140                        parents = c->parents;
 141                        nth = 0;
 142                        while (parents) {
 143                                struct commit *p = parents->item;
 144                                char newname[1000], *en;
 145                                parents = parents->next;
 146                                nth++;
 147                                if (p->util)
 148                                        continue;
 149                                en = newname;
 150                                switch (n->generation) {
 151                                case 0:
 152                                        en += sprintf(en, "%s", n->head_name);
 153                                        break;
 154                                case 1:
 155                                        en += sprintf(en, "%s^", n->head_name);
 156                                        break;
 157                                default:
 158                                        en += sprintf(en, "%s~%d",
 159                                                n->head_name, n->generation);
 160                                        break;
 161                                }
 162                                if (nth == 1)
 163                                        en += sprintf(en, "^");
 164                                else
 165                                        en += sprintf(en, "^%d", nth);
 166                                name_commit(p, xstrdup(newname), 0);
 167                                i++;
 168                                name_first_parent_chain(p);
 169                        }
 170                }
 171        } while (i);
 172}
 173
 174static int mark_seen(struct commit *commit, struct commit_list **seen_p)
 175{
 176        if (!commit->object.flags) {
 177                commit_list_insert(commit, seen_p);
 178                return 1;
 179        }
 180        return 0;
 181}
 182
 183static void join_revs(struct commit_list **list_p,
 184                      struct commit_list **seen_p,
 185                      int num_rev, int extra)
 186{
 187        int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 188        int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 189
 190        while (*list_p) {
 191                struct commit_list *parents;
 192                int still_interesting = !!interesting(*list_p);
 193                struct commit *commit = pop_one_commit(list_p);
 194                int flags = commit->object.flags & all_mask;
 195
 196                if (!still_interesting && extra <= 0)
 197                        break;
 198
 199                mark_seen(commit, seen_p);
 200                if ((flags & all_revs) == all_revs)
 201                        flags |= UNINTERESTING;
 202                parents = commit->parents;
 203
 204                while (parents) {
 205                        struct commit *p = parents->item;
 206                        int this_flag = p->object.flags;
 207                        parents = parents->next;
 208                        if ((this_flag & flags) == flags)
 209                                continue;
 210                        if (!p->object.parsed)
 211                                parse_commit(p);
 212                        if (mark_seen(p, seen_p) && !still_interesting)
 213                                extra--;
 214                        p->object.flags |= flags;
 215                        insert_by_date(p, list_p);
 216                }
 217        }
 218
 219        /*
 220         * Postprocess to complete well-poisoning.
 221         *
 222         * At this point we have all the commits we have seen in
 223         * seen_p list.  Mark anything that can be reached from
 224         * uninteresting commits not interesting.
 225         */
 226        for (;;) {
 227                int changed = 0;
 228                struct commit_list *s;
 229                for (s = *seen_p; s; s = s->next) {
 230                        struct commit *c = s->item;
 231                        struct commit_list *parents;
 232
 233                        if (((c->object.flags & all_revs) != all_revs) &&
 234                            !(c->object.flags & UNINTERESTING))
 235                                continue;
 236
 237                        /* The current commit is either a merge base or
 238                         * already uninteresting one.  Mark its parents
 239                         * as uninteresting commits _only_ if they are
 240                         * already parsed.  No reason to find new ones
 241                         * here.
 242                         */
 243                        parents = c->parents;
 244                        while (parents) {
 245                                struct commit *p = parents->item;
 246                                parents = parents->next;
 247                                if (!(p->object.flags & UNINTERESTING)) {
 248                                        p->object.flags |= UNINTERESTING;
 249                                        changed = 1;
 250                                }
 251                        }
 252                }
 253                if (!changed)
 254                        break;
 255        }
 256}
 257
 258static void show_one_commit(struct commit *commit, int no_name)
 259{
 260        char pretty[256], *cp;
 261        struct commit_name *name = commit->util;
 262        if (commit->object.parsed)
 263                pretty_print_commit(CMIT_FMT_ONELINE, commit, ~0,
 264                                    pretty, sizeof(pretty), 0, NULL, NULL, 0);
 265        else
 266                strcpy(pretty, "(unavailable)");
 267        if (!strncmp(pretty, "[PATCH] ", 8))
 268                cp = pretty + 8;
 269        else
 270                cp = pretty;
 271
 272        if (!no_name) {
 273                if (name && name->head_name) {
 274                        printf("[%s", name->head_name);
 275                        if (name->generation) {
 276                                if (name->generation == 1)
 277                                        printf("^");
 278                                else
 279                                        printf("~%d", name->generation);
 280                        }
 281                        printf("] ");
 282                }
 283                else
 284                        printf("[%s] ",
 285                               find_unique_abbrev(commit->object.sha1, 7));
 286        }
 287        puts(cp);
 288}
 289
 290static char *ref_name[MAX_REVS + 1];
 291static int ref_name_cnt;
 292
 293static const char *find_digit_prefix(const char *s, int *v)
 294{
 295        const char *p;
 296        int ver;
 297        char ch;
 298
 299        for (p = s, ver = 0;
 300             '0' <= (ch = *p) && ch <= '9';
 301             p++)
 302                ver = ver * 10 + ch - '0';
 303        *v = ver;
 304        return p;
 305}
 306
 307
 308static int version_cmp(const char *a, const char *b)
 309{
 310        while (1) {
 311                int va, vb;
 312
 313                a = find_digit_prefix(a, &va);
 314                b = find_digit_prefix(b, &vb);
 315                if (va != vb)
 316                        return va - vb;
 317
 318                while (1) {
 319                        int ca = *a;
 320                        int cb = *b;
 321                        if ('0' <= ca && ca <= '9')
 322                                ca = 0;
 323                        if ('0' <= cb && cb <= '9')
 324                                cb = 0;
 325                        if (ca != cb)
 326                                return ca - cb;
 327                        if (!ca)
 328                                break;
 329                        a++;
 330                        b++;
 331                }
 332                if (!*a && !*b)
 333                        return 0;
 334        }
 335}
 336
 337static int compare_ref_name(const void *a_, const void *b_)
 338{
 339        const char * const*a = a_, * const*b = b_;
 340        return version_cmp(*a, *b);
 341}
 342
 343static void sort_ref_range(int bottom, int top)
 344{
 345        qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
 346              compare_ref_name);
 347}
 348
 349static int append_ref(const char *refname, const unsigned char *sha1,
 350                      int allow_dups)
 351{
 352        struct commit *commit = lookup_commit_reference_gently(sha1, 1);
 353        int i;
 354
 355        if (!commit)
 356                return 0;
 357
 358        if (!allow_dups) {
 359                /* Avoid adding the same thing twice */
 360                for (i = 0; i < ref_name_cnt; i++)
 361                        if (!strcmp(refname, ref_name[i]))
 362                                return 0;
 363        }
 364        if (MAX_REVS <= ref_name_cnt) {
 365                fprintf(stderr, "warning: ignoring %s; "
 366                        "cannot handle more than %d refs\n",
 367                        refname, MAX_REVS);
 368                return 0;
 369        }
 370        ref_name[ref_name_cnt++] = xstrdup(refname);
 371        ref_name[ref_name_cnt] = NULL;
 372        return 0;
 373}
 374
 375static int append_head_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 376{
 377        unsigned char tmp[20];
 378        int ofs = 11;
 379        if (strncmp(refname, "refs/heads/", ofs))
 380                return 0;
 381        /* If both heads/foo and tags/foo exists, get_sha1 would
 382         * get confused.
 383         */
 384        if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
 385                ofs = 5;
 386        return append_ref(refname + ofs, sha1, 0);
 387}
 388
 389static int append_remote_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 390{
 391        unsigned char tmp[20];
 392        int ofs = 13;
 393        if (strncmp(refname, "refs/remotes/", ofs))
 394                return 0;
 395        /* If both heads/foo and tags/foo exists, get_sha1 would
 396         * get confused.
 397         */
 398        if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
 399                ofs = 5;
 400        return append_ref(refname + ofs, sha1, 0);
 401}
 402
 403static int append_tag_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 404{
 405        if (strncmp(refname, "refs/tags/", 10))
 406                return 0;
 407        return append_ref(refname + 5, sha1, 0);
 408}
 409
 410static const char *match_ref_pattern = NULL;
 411static int match_ref_slash = 0;
 412static int count_slash(const char *s)
 413{
 414        int cnt = 0;
 415        while (*s)
 416                if (*s++ == '/')
 417                        cnt++;
 418        return cnt;
 419}
 420
 421static int append_matching_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 422{
 423        /* we want to allow pattern hold/<asterisk> to show all
 424         * branches under refs/heads/hold/, and v0.99.9? to show
 425         * refs/tags/v0.99.9a and friends.
 426         */
 427        const char *tail;
 428        int slash = count_slash(refname);
 429        for (tail = refname; *tail && match_ref_slash < slash; )
 430                if (*tail++ == '/')
 431                        slash--;
 432        if (!*tail)
 433                return 0;
 434        if (fnmatch(match_ref_pattern, tail, 0))
 435                return 0;
 436        if (!strncmp("refs/heads/", refname, 11))
 437                return append_head_ref(refname, sha1, flag, cb_data);
 438        if (!strncmp("refs/tags/", refname, 10))
 439                return append_tag_ref(refname, sha1, flag, cb_data);
 440        return append_ref(refname, sha1, 0);
 441}
 442
 443static void snarf_refs(int head, int remotes)
 444{
 445        if (head) {
 446                int orig_cnt = ref_name_cnt;
 447                for_each_ref(append_head_ref, NULL);
 448                sort_ref_range(orig_cnt, ref_name_cnt);
 449        }
 450        if (remotes) {
 451                int orig_cnt = ref_name_cnt;
 452                for_each_ref(append_remote_ref, NULL);
 453                sort_ref_range(orig_cnt, ref_name_cnt);
 454        }
 455}
 456
 457static int rev_is_head(char *head, int headlen, char *name,
 458                       unsigned char *head_sha1, unsigned char *sha1)
 459{
 460        if ((!head[0]) ||
 461            (head_sha1 && sha1 && hashcmp(head_sha1, sha1)))
 462                return 0;
 463        if (!strncmp(head, "refs/heads/", 11))
 464                head += 11;
 465        if (!strncmp(name, "refs/heads/", 11))
 466                name += 11;
 467        else if (!strncmp(name, "heads/", 6))
 468                name += 6;
 469        return !strcmp(head, name);
 470}
 471
 472static int show_merge_base(struct commit_list *seen, int num_rev)
 473{
 474        int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 475        int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 476        int exit_status = 1;
 477
 478        while (seen) {
 479                struct commit *commit = pop_one_commit(&seen);
 480                int flags = commit->object.flags & all_mask;
 481                if (!(flags & UNINTERESTING) &&
 482                    ((flags & all_revs) == all_revs)) {
 483                        puts(sha1_to_hex(commit->object.sha1));
 484                        exit_status = 0;
 485                        commit->object.flags |= UNINTERESTING;
 486                }
 487        }
 488        return exit_status;
 489}
 490
 491static int show_independent(struct commit **rev,
 492                            int num_rev,
 493                            char **ref_name,
 494                            unsigned int *rev_mask)
 495{
 496        int i;
 497
 498        for (i = 0; i < num_rev; i++) {
 499                struct commit *commit = rev[i];
 500                unsigned int flag = rev_mask[i];
 501
 502                if (commit->object.flags == flag)
 503                        puts(sha1_to_hex(commit->object.sha1));
 504                commit->object.flags |= UNINTERESTING;
 505        }
 506        return 0;
 507}
 508
 509static void append_one_rev(const char *av)
 510{
 511        unsigned char revkey[20];
 512        if (!get_sha1(av, revkey)) {
 513                append_ref(av, revkey, 0);
 514                return;
 515        }
 516        if (strchr(av, '*') || strchr(av, '?') || strchr(av, '[')) {
 517                /* glob style match */
 518                int saved_matches = ref_name_cnt;
 519                match_ref_pattern = av;
 520                match_ref_slash = count_slash(av);
 521                for_each_ref(append_matching_ref, NULL);
 522                if (saved_matches == ref_name_cnt &&
 523                    ref_name_cnt < MAX_REVS)
 524                        error("no matching refs with %s", av);
 525                if (saved_matches + 1 < ref_name_cnt)
 526                        sort_ref_range(saved_matches, ref_name_cnt);
 527                return;
 528        }
 529        die("bad sha1 reference %s", av);
 530}
 531
 532static int git_show_branch_config(const char *var, const char *value)
 533{
 534        if (!strcmp(var, "showbranch.default")) {
 535                if (default_alloc <= default_num + 1) {
 536                        default_alloc = default_alloc * 3 / 2 + 20;
 537                        default_arg = xrealloc(default_arg, sizeof *default_arg * default_alloc);
 538                }
 539                default_arg[default_num++] = xstrdup(value);
 540                default_arg[default_num] = NULL;
 541                return 0;
 542        }
 543
 544        return git_default_config(var, value);
 545}
 546
 547static int omit_in_dense(struct commit *commit, struct commit **rev, int n)
 548{
 549        /* If the commit is tip of the named branches, do not
 550         * omit it.
 551         * Otherwise, if it is a merge that is reachable from only one
 552         * tip, it is not that interesting.
 553         */
 554        int i, flag, count;
 555        for (i = 0; i < n; i++)
 556                if (rev[i] == commit)
 557                        return 0;
 558        flag = commit->object.flags;
 559        for (i = count = 0; i < n; i++) {
 560                if (flag & (1u << (i + REV_SHIFT)))
 561                        count++;
 562        }
 563        if (count == 1)
 564                return 1;
 565        return 0;
 566}
 567
 568static void parse_reflog_param(const char *arg, int *cnt, const char **base)
 569{
 570        char *ep;
 571        *cnt = strtoul(arg, &ep, 10);
 572        if (*ep == ',')
 573                *base = ep + 1;
 574        else if (*ep)
 575                die("unrecognized reflog param '%s'", arg + 9);
 576        else
 577                *base = NULL;
 578        if (*cnt <= 0)
 579                *cnt = DEFAULT_REFLOG;
 580}
 581
 582int cmd_show_branch(int ac, const char **av, const char *prefix)
 583{
 584        struct commit *rev[MAX_REVS], *commit;
 585        char *reflog_msg[MAX_REVS];
 586        struct commit_list *list = NULL, *seen = NULL;
 587        unsigned int rev_mask[MAX_REVS];
 588        int num_rev, i, extra = 0;
 589        int all_heads = 0, all_remotes = 0;
 590        int all_mask, all_revs;
 591        int lifo = 1;
 592        char head[128];
 593        const char *head_p;
 594        int head_len;
 595        unsigned char head_sha1[20];
 596        int merge_base = 0;
 597        int independent = 0;
 598        int no_name = 0;
 599        int sha1_name = 0;
 600        int shown_merge_point = 0;
 601        int with_current_branch = 0;
 602        int head_at = -1;
 603        int topics = 0;
 604        int dense = 1;
 605        int reflog = 0;
 606        const char *reflog_base = NULL;
 607
 608        git_config(git_show_branch_config);
 609
 610        /* If nothing is specified, try the default first */
 611        if (ac == 1 && default_num) {
 612                ac = default_num + 1;
 613                av = default_arg - 1; /* ick; we would not address av[0] */
 614        }
 615
 616        while (1 < ac && av[1][0] == '-') {
 617                const char *arg = av[1];
 618                if (!strcmp(arg, "--")) {
 619                        ac--; av++;
 620                        break;
 621                }
 622                else if (!strcmp(arg, "--all") || !strcmp(arg, "-a"))
 623                        all_heads = all_remotes = 1;
 624                else if (!strcmp(arg, "--remotes") || !strcmp(arg, "-r"))
 625                        all_remotes = 1;
 626                else if (!strcmp(arg, "--more"))
 627                        extra = 1;
 628                else if (!strcmp(arg, "--list"))
 629                        extra = -1;
 630                else if (!strcmp(arg, "--no-name"))
 631                        no_name = 1;
 632                else if (!strcmp(arg, "--current"))
 633                        with_current_branch = 1;
 634                else if (!strcmp(arg, "--sha1-name"))
 635                        sha1_name = 1;
 636                else if (!strncmp(arg, "--more=", 7))
 637                        extra = atoi(arg + 7);
 638                else if (!strcmp(arg, "--merge-base"))
 639                        merge_base = 1;
 640                else if (!strcmp(arg, "--independent"))
 641                        independent = 1;
 642                else if (!strcmp(arg, "--topo-order"))
 643                        lifo = 1;
 644                else if (!strcmp(arg, "--topics"))
 645                        topics = 1;
 646                else if (!strcmp(arg, "--sparse"))
 647                        dense = 0;
 648                else if (!strcmp(arg, "--date-order"))
 649                        lifo = 0;
 650                else if (!strcmp(arg, "--reflog")) {
 651                        reflog = DEFAULT_REFLOG;
 652                }
 653                else if (!strncmp(arg, "--reflog=", 9))
 654                        parse_reflog_param(arg + 9, &reflog, &reflog_base);
 655                else
 656                        usage(show_branch_usage);
 657                ac--; av++;
 658        }
 659        ac--; av++;
 660
 661        if (!!extra || !!reflog) {
 662                /* "listing" mode is incompatible with
 663                 * independent nor merge-base modes.
 664                 */
 665                if (independent || merge_base)
 666                        usage(show_branch_usage);
 667                if (!!reflog && (0 < extra))
 668                        /*
 669                         * Asking for --more in reflog mode does not
 670                         * make sense.
 671                         */
 672                        usage(show_branch_usage);
 673        }
 674
 675        /* If nothing is specified, show all branches by default */
 676        if (ac + all_heads + all_remotes == 0)
 677                all_heads = 1;
 678
 679        if (all_heads + all_remotes)
 680                snarf_refs(all_heads, all_remotes);
 681        if (reflog) {
 682                unsigned char sha1[20];
 683                char nth_desc[256];
 684                char *ref;
 685                int base = 0;
 686                if (ac != 1)
 687                        die("--reflog option needs one branch name");
 688                if (!dwim_ref(*av, strlen(*av), sha1, &ref))
 689                        die("No such ref %s", *av);
 690
 691                /* Has the base been specified? */
 692                if (reflog_base) {
 693                        char *ep;
 694                        base = strtoul(reflog_base, &ep, 10);
 695                        if (*ep) {
 696                                /* Ah, that is a date spec... */
 697                                unsigned long at;
 698                                at = approxidate(reflog_base);
 699                                read_ref_at(ref, at, -1, sha1, NULL,
 700                                            NULL, NULL, &base);
 701                        }
 702                }
 703
 704                for (i = 0; i < reflog; i++) {
 705                        char *logmsg, *msg, *m;
 706                        unsigned long timestamp;
 707                        int tz;
 708
 709                        if (read_ref_at(ref, 0, base+i, sha1, &logmsg,
 710                                        &timestamp, &tz, NULL)) {
 711                                reflog = i;
 712                                break;
 713                        }
 714                        msg = strchr(logmsg, '\t');
 715                        if (!msg)
 716                                msg = "(none)";
 717                        else
 718                                msg++;
 719                        m = xmalloc(strlen(msg) + 200);
 720                        sprintf(m, "(%s) %s",
 721                                show_date(timestamp, 0, 1),
 722                                msg);
 723                        reflog_msg[i] = m;
 724                        free(logmsg);
 725                        sprintf(nth_desc, "%s@{%d}", *av, base+i);
 726                        append_ref(nth_desc, sha1, 1);
 727                }
 728        }
 729        else {
 730                while (0 < ac) {
 731                        append_one_rev(*av);
 732                        ac--; av++;
 733                }
 734        }
 735
 736        head_p = resolve_ref("HEAD", head_sha1, 1, NULL);
 737        if (head_p) {
 738                head_len = strlen(head_p);
 739                memcpy(head, head_p, head_len + 1);
 740        }
 741        else {
 742                head_len = 0;
 743                head[0] = 0;
 744        }
 745
 746        if (with_current_branch && head_p) {
 747                int has_head = 0;
 748                for (i = 0; !has_head && i < ref_name_cnt; i++) {
 749                        /* We are only interested in adding the branch
 750                         * HEAD points at.
 751                         */
 752                        if (rev_is_head(head,
 753                                        head_len,
 754                                        ref_name[i],
 755                                        head_sha1, NULL))
 756                                has_head++;
 757                }
 758                if (!has_head) {
 759                        int pfxlen = strlen("refs/heads/");
 760                        append_one_rev(head + pfxlen);
 761                }
 762        }
 763
 764        if (!ref_name_cnt) {
 765                fprintf(stderr, "No revs to be shown.\n");
 766                exit(0);
 767        }
 768
 769        for (num_rev = 0; ref_name[num_rev]; num_rev++) {
 770                unsigned char revkey[20];
 771                unsigned int flag = 1u << (num_rev + REV_SHIFT);
 772
 773                if (MAX_REVS <= num_rev)
 774                        die("cannot handle more than %d revs.", MAX_REVS);
 775                if (get_sha1(ref_name[num_rev], revkey))
 776                        die("'%s' is not a valid ref.", ref_name[num_rev]);
 777                commit = lookup_commit_reference(revkey);
 778                if (!commit)
 779                        die("cannot find commit %s (%s)",
 780                            ref_name[num_rev], revkey);
 781                parse_commit(commit);
 782                mark_seen(commit, &seen);
 783
 784                /* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
 785                 * and so on.  REV_SHIFT bits from bit 0 are used for
 786                 * internal bookkeeping.
 787                 */
 788                commit->object.flags |= flag;
 789                if (commit->object.flags == flag)
 790                        insert_by_date(commit, &list);
 791                rev[num_rev] = commit;
 792        }
 793        for (i = 0; i < num_rev; i++)
 794                rev_mask[i] = rev[i]->object.flags;
 795
 796        if (0 <= extra)
 797                join_revs(&list, &seen, num_rev, extra);
 798
 799        sort_by_date(&seen);
 800
 801        if (merge_base)
 802                return show_merge_base(seen, num_rev);
 803
 804        if (independent)
 805                return show_independent(rev, num_rev, ref_name, rev_mask);
 806
 807        /* Show list; --more=-1 means list-only */
 808        if (1 < num_rev || extra < 0) {
 809                for (i = 0; i < num_rev; i++) {
 810                        int j;
 811                        int is_head = rev_is_head(head,
 812                                                  head_len,
 813                                                  ref_name[i],
 814                                                  head_sha1,
 815                                                  rev[i]->object.sha1);
 816                        if (extra < 0)
 817                                printf("%c [%s] ",
 818                                       is_head ? '*' : ' ', ref_name[i]);
 819                        else {
 820                                for (j = 0; j < i; j++)
 821                                        putchar(' ');
 822                                printf("%c [%s] ",
 823                                       is_head ? '*' : '!', ref_name[i]);
 824                        }
 825
 826                        if (!reflog) {
 827                                /* header lines never need name */
 828                                show_one_commit(rev[i], 1);
 829                        }
 830                        else
 831                                puts(reflog_msg[i]);
 832
 833                        if (is_head)
 834                                head_at = i;
 835                }
 836                if (0 <= extra) {
 837                        for (i = 0; i < num_rev; i++)
 838                                putchar('-');
 839                        putchar('\n');
 840                }
 841        }
 842        if (extra < 0)
 843                exit(0);
 844
 845        /* Sort topologically */
 846        sort_in_topological_order(&seen, lifo);
 847
 848        /* Give names to commits */
 849        if (!sha1_name && !no_name)
 850                name_commits(seen, rev, ref_name, num_rev);
 851
 852        all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 853        all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 854
 855        while (seen) {
 856                struct commit *commit = pop_one_commit(&seen);
 857                int this_flag = commit->object.flags;
 858                int is_merge_point = ((this_flag & all_revs) == all_revs);
 859
 860                shown_merge_point |= is_merge_point;
 861
 862                if (1 < num_rev) {
 863                        int is_merge = !!(commit->parents &&
 864                                          commit->parents->next);
 865                        if (topics &&
 866                            !is_merge_point &&
 867                            (this_flag & (1u << REV_SHIFT)))
 868                                continue;
 869                        if (dense && is_merge &&
 870                            omit_in_dense(commit, rev, num_rev))
 871                                continue;
 872                        for (i = 0; i < num_rev; i++) {
 873                                int mark;
 874                                if (!(this_flag & (1u << (i + REV_SHIFT))))
 875                                        mark = ' ';
 876                                else if (is_merge)
 877                                        mark = '-';
 878                                else if (i == head_at)
 879                                        mark = '*';
 880                                else
 881                                        mark = '+';
 882                                putchar(mark);
 883                        }
 884                        putchar(' ');
 885                }
 886                show_one_commit(commit, no_name);
 887
 888                if (shown_merge_point && --extra < 0)
 889                        break;
 890        }
 891        return 0;
 892}