Andrew's git / gitweb.git / builtin-show-branch.c
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builtin-show-branch.con commit Update draft Release Notes for 1.5.3 (14a4091)
   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[,b]] <branch>";
   8static const char show_branch_usage_reflog[] =
   9"--reflog is incompatible with --all, --remotes, --independent or --merge-base";
  10
  11static int default_num;
  12static int default_alloc;
  13static const char **default_arg;
  14
  15#define UNINTERESTING   01
  16
  17#define REV_SHIFT        2
  18#define MAX_REVS        (FLAG_BITS - REV_SHIFT) /* should not exceed bits_per_int - REV_SHIFT */
  19
  20#define DEFAULT_REFLOG  4
  21
  22static struct commit *interesting(struct commit_list *list)
  23{
  24        while (list) {
  25                struct commit *commit = list->item;
  26                list = list->next;
  27                if (commit->object.flags & UNINTERESTING)
  28                        continue;
  29                return commit;
  30        }
  31        return NULL;
  32}
  33
  34static struct commit *pop_one_commit(struct commit_list **list_p)
  35{
  36        struct commit *commit;
  37        struct commit_list *list;
  38        list = *list_p;
  39        commit = list->item;
  40        *list_p = list->next;
  41        free(list);
  42        return commit;
  43}
  44
  45struct commit_name {
  46        const char *head_name; /* which head's ancestor? */
  47        int generation; /* how many parents away from head_name */
  48};
  49
  50/* Name the commit as nth generation ancestor of head_name;
  51 * we count only the first-parent relationship for naming purposes.
  52 */
  53static void name_commit(struct commit *commit, const char *head_name, int nth)
  54{
  55        struct commit_name *name;
  56        if (!commit->util)
  57                commit->util = xmalloc(sizeof(struct commit_name));
  58        name = commit->util;
  59        name->head_name = head_name;
  60        name->generation = nth;
  61}
  62
  63/* Parent is the first parent of the commit.  We may name it
  64 * as (n+1)th generation ancestor of the same head_name as
  65 * commit is nth generation ancestor of, if that generation
  66 * number is better than the name it already has.
  67 */
  68static void name_parent(struct commit *commit, struct commit *parent)
  69{
  70        struct commit_name *commit_name = commit->util;
  71        struct commit_name *parent_name = parent->util;
  72        if (!commit_name)
  73                return;
  74        if (!parent_name ||
  75            commit_name->generation + 1 < parent_name->generation)
  76                name_commit(parent, commit_name->head_name,
  77                            commit_name->generation + 1);
  78}
  79
  80static int name_first_parent_chain(struct commit *c)
  81{
  82        int i = 0;
  83        while (c) {
  84                struct commit *p;
  85                if (!c->util)
  86                        break;
  87                if (!c->parents)
  88                        break;
  89                p = c->parents->item;
  90                if (!p->util) {
  91                        name_parent(c, p);
  92                        i++;
  93                }
  94                else
  95                        break;
  96                c = p;
  97        }
  98        return i;
  99}
 100
 101static void name_commits(struct commit_list *list,
 102                         struct commit **rev,
 103                         char **ref_name,
 104                         int num_rev)
 105{
 106        struct commit_list *cl;
 107        struct commit *c;
 108        int i;
 109
 110        /* First give names to the given heads */
 111        for (cl = list; cl; cl = cl->next) {
 112                c = cl->item;
 113                if (c->util)
 114                        continue;
 115                for (i = 0; i < num_rev; i++) {
 116                        if (rev[i] == c) {
 117                                name_commit(c, ref_name[i], 0);
 118                                break;
 119                        }
 120                }
 121        }
 122
 123        /* Then commits on the first parent ancestry chain */
 124        do {
 125                i = 0;
 126                for (cl = list; cl; cl = cl->next) {
 127                        i += name_first_parent_chain(cl->item);
 128                }
 129        } while (i);
 130
 131        /* Finally, any unnamed commits */
 132        do {
 133                i = 0;
 134                for (cl = list; cl; cl = cl->next) {
 135                        struct commit_list *parents;
 136                        struct commit_name *n;
 137                        int nth;
 138                        c = cl->item;
 139                        if (!c->util)
 140                                continue;
 141                        n = c->util;
 142                        parents = c->parents;
 143                        nth = 0;
 144                        while (parents) {
 145                                struct commit *p = parents->item;
 146                                char newname[1000], *en;
 147                                parents = parents->next;
 148                                nth++;
 149                                if (p->util)
 150                                        continue;
 151                                en = newname;
 152                                switch (n->generation) {
 153                                case 0:
 154                                        en += sprintf(en, "%s", n->head_name);
 155                                        break;
 156                                case 1:
 157                                        en += sprintf(en, "%s^", n->head_name);
 158                                        break;
 159                                default:
 160                                        en += sprintf(en, "%s~%d",
 161                                                n->head_name, n->generation);
 162                                        break;
 163                                }
 164                                if (nth == 1)
 165                                        en += sprintf(en, "^");
 166                                else
 167                                        en += sprintf(en, "^%d", nth);
 168                                name_commit(p, xstrdup(newname), 0);
 169                                i++;
 170                                name_first_parent_chain(p);
 171                        }
 172                }
 173        } while (i);
 174}
 175
 176static int mark_seen(struct commit *commit, struct commit_list **seen_p)
 177{
 178        if (!commit->object.flags) {
 179                commit_list_insert(commit, seen_p);
 180                return 1;
 181        }
 182        return 0;
 183}
 184
 185static void join_revs(struct commit_list **list_p,
 186                      struct commit_list **seen_p,
 187                      int num_rev, int extra)
 188{
 189        int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 190        int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 191
 192        while (*list_p) {
 193                struct commit_list *parents;
 194                int still_interesting = !!interesting(*list_p);
 195                struct commit *commit = pop_one_commit(list_p);
 196                int flags = commit->object.flags & all_mask;
 197
 198                if (!still_interesting && extra <= 0)
 199                        break;
 200
 201                mark_seen(commit, seen_p);
 202                if ((flags & all_revs) == all_revs)
 203                        flags |= UNINTERESTING;
 204                parents = commit->parents;
 205
 206                while (parents) {
 207                        struct commit *p = parents->item;
 208                        int this_flag = p->object.flags;
 209                        parents = parents->next;
 210                        if ((this_flag & flags) == flags)
 211                                continue;
 212                        if (!p->object.parsed)
 213                                parse_commit(p);
 214                        if (mark_seen(p, seen_p) && !still_interesting)
 215                                extra--;
 216                        p->object.flags |= flags;
 217                        insert_by_date(p, list_p);
 218                }
 219        }
 220
 221        /*
 222         * Postprocess to complete well-poisoning.
 223         *
 224         * At this point we have all the commits we have seen in
 225         * seen_p list.  Mark anything that can be reached from
 226         * uninteresting commits not interesting.
 227         */
 228        for (;;) {
 229                int changed = 0;
 230                struct commit_list *s;
 231                for (s = *seen_p; s; s = s->next) {
 232                        struct commit *c = s->item;
 233                        struct commit_list *parents;
 234
 235                        if (((c->object.flags & all_revs) != all_revs) &&
 236                            !(c->object.flags & UNINTERESTING))
 237                                continue;
 238
 239                        /* The current commit is either a merge base or
 240                         * already uninteresting one.  Mark its parents
 241                         * as uninteresting commits _only_ if they are
 242                         * already parsed.  No reason to find new ones
 243                         * here.
 244                         */
 245                        parents = c->parents;
 246                        while (parents) {
 247                                struct commit *p = parents->item;
 248                                parents = parents->next;
 249                                if (!(p->object.flags & UNINTERESTING)) {
 250                                        p->object.flags |= UNINTERESTING;
 251                                        changed = 1;
 252                                }
 253                        }
 254                }
 255                if (!changed)
 256                        break;
 257        }
 258}
 259
 260static void show_one_commit(struct commit *commit, int no_name)
 261{
 262        char *pretty = NULL;
 263        const char *pretty_str = "(unavailable)";
 264        unsigned long pretty_len = 0;
 265        struct commit_name *name = commit->util;
 266
 267        if (commit->object.parsed) {
 268                pretty_print_commit(CMIT_FMT_ONELINE, commit, ~0,
 269                                    &pretty, &pretty_len,
 270                                    0, NULL, NULL, 0);
 271                pretty_str = pretty;
 272        }
 273        if (!prefixcmp(pretty_str, "[PATCH] "))
 274                pretty_str += 8;
 275
 276        if (!no_name) {
 277                if (name && name->head_name) {
 278                        printf("[%s", name->head_name);
 279                        if (name->generation) {
 280                                if (name->generation == 1)
 281                                        printf("^");
 282                                else
 283                                        printf("~%d", name->generation);
 284                        }
 285                        printf("] ");
 286                }
 287                else
 288                        printf("[%s] ",
 289                               find_unique_abbrev(commit->object.sha1, 7));
 290        }
 291        puts(pretty_str);
 292        free(pretty);
 293}
 294
 295static char *ref_name[MAX_REVS + 1];
 296static int ref_name_cnt;
 297
 298static const char *find_digit_prefix(const char *s, int *v)
 299{
 300        const char *p;
 301        int ver;
 302        char ch;
 303
 304        for (p = s, ver = 0;
 305             '0' <= (ch = *p) && ch <= '9';
 306             p++)
 307                ver = ver * 10 + ch - '0';
 308        *v = ver;
 309        return p;
 310}
 311
 312
 313static int version_cmp(const char *a, const char *b)
 314{
 315        while (1) {
 316                int va, vb;
 317
 318                a = find_digit_prefix(a, &va);
 319                b = find_digit_prefix(b, &vb);
 320                if (va != vb)
 321                        return va - vb;
 322
 323                while (1) {
 324                        int ca = *a;
 325                        int cb = *b;
 326                        if ('0' <= ca && ca <= '9')
 327                                ca = 0;
 328                        if ('0' <= cb && cb <= '9')
 329                                cb = 0;
 330                        if (ca != cb)
 331                                return ca - cb;
 332                        if (!ca)
 333                                break;
 334                        a++;
 335                        b++;
 336                }
 337                if (!*a && !*b)
 338                        return 0;
 339        }
 340}
 341
 342static int compare_ref_name(const void *a_, const void *b_)
 343{
 344        const char * const*a = a_, * const*b = b_;
 345        return version_cmp(*a, *b);
 346}
 347
 348static void sort_ref_range(int bottom, int top)
 349{
 350        qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
 351              compare_ref_name);
 352}
 353
 354static int append_ref(const char *refname, const unsigned char *sha1,
 355                      int allow_dups)
 356{
 357        struct commit *commit = lookup_commit_reference_gently(sha1, 1);
 358        int i;
 359
 360        if (!commit)
 361                return 0;
 362
 363        if (!allow_dups) {
 364                /* Avoid adding the same thing twice */
 365                for (i = 0; i < ref_name_cnt; i++)
 366                        if (!strcmp(refname, ref_name[i]))
 367                                return 0;
 368        }
 369        if (MAX_REVS <= ref_name_cnt) {
 370                fprintf(stderr, "warning: ignoring %s; "
 371                        "cannot handle more than %d refs\n",
 372                        refname, MAX_REVS);
 373                return 0;
 374        }
 375        ref_name[ref_name_cnt++] = xstrdup(refname);
 376        ref_name[ref_name_cnt] = NULL;
 377        return 0;
 378}
 379
 380static int append_head_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 381{
 382        unsigned char tmp[20];
 383        int ofs = 11;
 384        if (prefixcmp(refname, "refs/heads/"))
 385                return 0;
 386        /* If both heads/foo and tags/foo exists, get_sha1 would
 387         * get confused.
 388         */
 389        if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
 390                ofs = 5;
 391        return append_ref(refname + ofs, sha1, 0);
 392}
 393
 394static int append_remote_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 395{
 396        unsigned char tmp[20];
 397        int ofs = 13;
 398        if (prefixcmp(refname, "refs/remotes/"))
 399                return 0;
 400        /* If both heads/foo and tags/foo exists, get_sha1 would
 401         * get confused.
 402         */
 403        if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
 404                ofs = 5;
 405        return append_ref(refname + ofs, sha1, 0);
 406}
 407
 408static int append_tag_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 409{
 410        if (prefixcmp(refname, "refs/tags/"))
 411                return 0;
 412        return append_ref(refname + 5, sha1, 0);
 413}
 414
 415static const char *match_ref_pattern = NULL;
 416static int match_ref_slash = 0;
 417static int count_slash(const char *s)
 418{
 419        int cnt = 0;
 420        while (*s)
 421                if (*s++ == '/')
 422                        cnt++;
 423        return cnt;
 424}
 425
 426static int append_matching_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 427{
 428        /* we want to allow pattern hold/<asterisk> to show all
 429         * branches under refs/heads/hold/, and v0.99.9? to show
 430         * refs/tags/v0.99.9a and friends.
 431         */
 432        const char *tail;
 433        int slash = count_slash(refname);
 434        for (tail = refname; *tail && match_ref_slash < slash; )
 435                if (*tail++ == '/')
 436                        slash--;
 437        if (!*tail)
 438                return 0;
 439        if (fnmatch(match_ref_pattern, tail, 0))
 440                return 0;
 441        if (!prefixcmp(refname, "refs/heads/"))
 442                return append_head_ref(refname, sha1, flag, cb_data);
 443        if (!prefixcmp(refname, "refs/tags/"))
 444                return append_tag_ref(refname, sha1, flag, cb_data);
 445        return append_ref(refname, sha1, 0);
 446}
 447
 448static void snarf_refs(int head, int remotes)
 449{
 450        if (head) {
 451                int orig_cnt = ref_name_cnt;
 452                for_each_ref(append_head_ref, NULL);
 453                sort_ref_range(orig_cnt, ref_name_cnt);
 454        }
 455        if (remotes) {
 456                int orig_cnt = ref_name_cnt;
 457                for_each_ref(append_remote_ref, NULL);
 458                sort_ref_range(orig_cnt, ref_name_cnt);
 459        }
 460}
 461
 462static int rev_is_head(char *head, int headlen, char *name,
 463                       unsigned char *head_sha1, unsigned char *sha1)
 464{
 465        if ((!head[0]) ||
 466            (head_sha1 && sha1 && hashcmp(head_sha1, sha1)))
 467                return 0;
 468        if (!prefixcmp(head, "refs/heads/"))
 469                head += 11;
 470        if (!prefixcmp(name, "refs/heads/"))
 471                name += 11;
 472        else if (!prefixcmp(name, "heads/"))
 473                name += 6;
 474        return !strcmp(head, name);
 475}
 476
 477static int show_merge_base(struct commit_list *seen, int num_rev)
 478{
 479        int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 480        int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 481        int exit_status = 1;
 482
 483        while (seen) {
 484                struct commit *commit = pop_one_commit(&seen);
 485                int flags = commit->object.flags & all_mask;
 486                if (!(flags & UNINTERESTING) &&
 487                    ((flags & all_revs) == all_revs)) {
 488                        puts(sha1_to_hex(commit->object.sha1));
 489                        exit_status = 0;
 490                        commit->object.flags |= UNINTERESTING;
 491                }
 492        }
 493        return exit_status;
 494}
 495
 496static int show_independent(struct commit **rev,
 497                            int num_rev,
 498                            char **ref_name,
 499                            unsigned int *rev_mask)
 500{
 501        int i;
 502
 503        for (i = 0; i < num_rev; i++) {
 504                struct commit *commit = rev[i];
 505                unsigned int flag = rev_mask[i];
 506
 507                if (commit->object.flags == flag)
 508                        puts(sha1_to_hex(commit->object.sha1));
 509                commit->object.flags |= UNINTERESTING;
 510        }
 511        return 0;
 512}
 513
 514static void append_one_rev(const char *av)
 515{
 516        unsigned char revkey[20];
 517        if (!get_sha1(av, revkey)) {
 518                append_ref(av, revkey, 0);
 519                return;
 520        }
 521        if (strchr(av, '*') || strchr(av, '?') || strchr(av, '[')) {
 522                /* glob style match */
 523                int saved_matches = ref_name_cnt;
 524                match_ref_pattern = av;
 525                match_ref_slash = count_slash(av);
 526                for_each_ref(append_matching_ref, NULL);
 527                if (saved_matches == ref_name_cnt &&
 528                    ref_name_cnt < MAX_REVS)
 529                        error("no matching refs with %s", av);
 530                if (saved_matches + 1 < ref_name_cnt)
 531                        sort_ref_range(saved_matches, ref_name_cnt);
 532                return;
 533        }
 534        die("bad sha1 reference %s", av);
 535}
 536
 537static int git_show_branch_config(const char *var, const char *value)
 538{
 539        if (!strcmp(var, "showbranch.default")) {
 540                if (default_alloc <= default_num + 1) {
 541                        default_alloc = default_alloc * 3 / 2 + 20;
 542                        default_arg = xrealloc(default_arg, sizeof *default_arg * default_alloc);
 543                }
 544                default_arg[default_num++] = xstrdup(value);
 545                default_arg[default_num] = NULL;
 546                return 0;
 547        }
 548
 549        return git_default_config(var, value);
 550}
 551
 552static int omit_in_dense(struct commit *commit, struct commit **rev, int n)
 553{
 554        /* If the commit is tip of the named branches, do not
 555         * omit it.
 556         * Otherwise, if it is a merge that is reachable from only one
 557         * tip, it is not that interesting.
 558         */
 559        int i, flag, count;
 560        for (i = 0; i < n; i++)
 561                if (rev[i] == commit)
 562                        return 0;
 563        flag = commit->object.flags;
 564        for (i = count = 0; i < n; i++) {
 565                if (flag & (1u << (i + REV_SHIFT)))
 566                        count++;
 567        }
 568        if (count == 1)
 569                return 1;
 570        return 0;
 571}
 572
 573static void parse_reflog_param(const char *arg, int *cnt, const char **base)
 574{
 575        char *ep;
 576        *cnt = strtoul(arg, &ep, 10);
 577        if (*ep == ',')
 578                *base = ep + 1;
 579        else if (*ep)
 580                die("unrecognized reflog param '%s'", arg + 9);
 581        else
 582                *base = NULL;
 583        if (*cnt <= 0)
 584                *cnt = DEFAULT_REFLOG;
 585}
 586
 587int cmd_show_branch(int ac, const char **av, const char *prefix)
 588{
 589        struct commit *rev[MAX_REVS], *commit;
 590        char *reflog_msg[MAX_REVS];
 591        struct commit_list *list = NULL, *seen = NULL;
 592        unsigned int rev_mask[MAX_REVS];
 593        int num_rev, i, extra = 0;
 594        int all_heads = 0, all_remotes = 0;
 595        int all_mask, all_revs;
 596        int lifo = 1;
 597        char head[128];
 598        const char *head_p;
 599        int head_len;
 600        unsigned char head_sha1[20];
 601        int merge_base = 0;
 602        int independent = 0;
 603        int no_name = 0;
 604        int sha1_name = 0;
 605        int shown_merge_point = 0;
 606        int with_current_branch = 0;
 607        int head_at = -1;
 608        int topics = 0;
 609        int dense = 1;
 610        int reflog = 0;
 611        const char *reflog_base = NULL;
 612
 613        git_config(git_show_branch_config);
 614
 615        /* If nothing is specified, try the default first */
 616        if (ac == 1 && default_num) {
 617                ac = default_num + 1;
 618                av = default_arg - 1; /* ick; we would not address av[0] */
 619        }
 620
 621        while (1 < ac && av[1][0] == '-') {
 622                const char *arg = av[1];
 623                if (!strcmp(arg, "--")) {
 624                        ac--; av++;
 625                        break;
 626                }
 627                else if (!strcmp(arg, "--all") || !strcmp(arg, "-a"))
 628                        all_heads = all_remotes = 1;
 629                else if (!strcmp(arg, "--remotes") || !strcmp(arg, "-r"))
 630                        all_remotes = 1;
 631                else if (!strcmp(arg, "--more"))
 632                        extra = 1;
 633                else if (!strcmp(arg, "--list"))
 634                        extra = -1;
 635                else if (!strcmp(arg, "--no-name"))
 636                        no_name = 1;
 637                else if (!strcmp(arg, "--current"))
 638                        with_current_branch = 1;
 639                else if (!strcmp(arg, "--sha1-name"))
 640                        sha1_name = 1;
 641                else if (!prefixcmp(arg, "--more="))
 642                        extra = atoi(arg + 7);
 643                else if (!strcmp(arg, "--merge-base"))
 644                        merge_base = 1;
 645                else if (!strcmp(arg, "--independent"))
 646                        independent = 1;
 647                else if (!strcmp(arg, "--topo-order"))
 648                        lifo = 1;
 649                else if (!strcmp(arg, "--topics"))
 650                        topics = 1;
 651                else if (!strcmp(arg, "--sparse"))
 652                        dense = 0;
 653                else if (!strcmp(arg, "--date-order"))
 654                        lifo = 0;
 655                else if (!strcmp(arg, "--reflog") || !strcmp(arg, "-g")) {
 656                        reflog = DEFAULT_REFLOG;
 657                }
 658                else if (!prefixcmp(arg, "--reflog="))
 659                        parse_reflog_param(arg + 9, &reflog, &reflog_base);
 660                else if (!prefixcmp(arg, "-g="))
 661                        parse_reflog_param(arg + 3, &reflog, &reflog_base);
 662                else
 663                        usage(show_branch_usage);
 664                ac--; av++;
 665        }
 666        ac--; av++;
 667
 668        if (extra || reflog) {
 669                /* "listing" mode is incompatible with
 670                 * independent nor merge-base modes.
 671                 */
 672                if (independent || merge_base)
 673                        usage(show_branch_usage);
 674                if (reflog && ((0 < extra) || all_heads || all_remotes))
 675                        /*
 676                         * Asking for --more in reflog mode does not
 677                         * make sense.  --list is Ok.
 678                         *
 679                         * Also --all and --remotes do not make sense either.
 680                         */
 681                        usage(show_branch_usage_reflog);
 682        }
 683
 684        /* If nothing is specified, show all branches by default */
 685        if (ac + all_heads + all_remotes == 0)
 686                all_heads = 1;
 687
 688        if (reflog) {
 689                unsigned char sha1[20];
 690                char nth_desc[256];
 691                char *ref;
 692                int base = 0;
 693
 694                if (ac == 0) {
 695                        static const char *fake_av[2];
 696                        const char *refname;
 697
 698                        refname = resolve_ref("HEAD", sha1, 1, NULL);
 699                        fake_av[0] = xstrdup(refname);
 700                        fake_av[1] = NULL;
 701                        av = fake_av;
 702                        ac = 1;
 703                }
 704                if (ac != 1)
 705                        die("--reflog option needs one branch name");
 706
 707                if (MAX_REVS < reflog)
 708                        die("Only %d entries can be shown at one time.",
 709                            MAX_REVS);
 710                if (!dwim_ref(*av, strlen(*av), sha1, &ref))
 711                        die("No such ref %s", *av);
 712
 713                /* Has the base been specified? */
 714                if (reflog_base) {
 715                        char *ep;
 716                        base = strtoul(reflog_base, &ep, 10);
 717                        if (*ep) {
 718                                /* Ah, that is a date spec... */
 719                                unsigned long at;
 720                                at = approxidate(reflog_base);
 721                                read_ref_at(ref, at, -1, sha1, NULL,
 722                                            NULL, NULL, &base);
 723                        }
 724                }
 725
 726                for (i = 0; i < reflog; i++) {
 727                        char *logmsg, *m;
 728                        const char *msg;
 729                        unsigned long timestamp;
 730                        int tz;
 731
 732                        if (read_ref_at(ref, 0, base+i, sha1, &logmsg,
 733                                        &timestamp, &tz, NULL)) {
 734                                reflog = i;
 735                                break;
 736                        }
 737                        msg = strchr(logmsg, '\t');
 738                        if (!msg)
 739                                msg = "(none)";
 740                        else
 741                                msg++;
 742                        m = xmalloc(strlen(msg) + 200);
 743                        sprintf(m, "(%s) %s",
 744                                show_date(timestamp, tz, 1),
 745                                msg);
 746                        reflog_msg[i] = m;
 747                        free(logmsg);
 748                        sprintf(nth_desc, "%s@{%d}", *av, base+i);
 749                        append_ref(nth_desc, sha1, 1);
 750                }
 751        }
 752        else if (all_heads + all_remotes)
 753                snarf_refs(all_heads, all_remotes);
 754        else {
 755                while (0 < ac) {
 756                        append_one_rev(*av);
 757                        ac--; av++;
 758                }
 759        }
 760
 761        head_p = resolve_ref("HEAD", head_sha1, 1, NULL);
 762        if (head_p) {
 763                head_len = strlen(head_p);
 764                memcpy(head, head_p, head_len + 1);
 765        }
 766        else {
 767                head_len = 0;
 768                head[0] = 0;
 769        }
 770
 771        if (with_current_branch && head_p) {
 772                int has_head = 0;
 773                for (i = 0; !has_head && i < ref_name_cnt; i++) {
 774                        /* We are only interested in adding the branch
 775                         * HEAD points at.
 776                         */
 777                        if (rev_is_head(head,
 778                                        head_len,
 779                                        ref_name[i],
 780                                        head_sha1, NULL))
 781                                has_head++;
 782                }
 783                if (!has_head) {
 784                        int pfxlen = strlen("refs/heads/");
 785                        append_one_rev(head + pfxlen);
 786                }
 787        }
 788
 789        if (!ref_name_cnt) {
 790                fprintf(stderr, "No revs to be shown.\n");
 791                exit(0);
 792        }
 793
 794        for (num_rev = 0; ref_name[num_rev]; num_rev++) {
 795                unsigned char revkey[20];
 796                unsigned int flag = 1u << (num_rev + REV_SHIFT);
 797
 798                if (MAX_REVS <= num_rev)
 799                        die("cannot handle more than %d revs.", MAX_REVS);
 800                if (get_sha1(ref_name[num_rev], revkey))
 801                        die("'%s' is not a valid ref.", ref_name[num_rev]);
 802                commit = lookup_commit_reference(revkey);
 803                if (!commit)
 804                        die("cannot find commit %s (%s)",
 805                            ref_name[num_rev], revkey);
 806                parse_commit(commit);
 807                mark_seen(commit, &seen);
 808
 809                /* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
 810                 * and so on.  REV_SHIFT bits from bit 0 are used for
 811                 * internal bookkeeping.
 812                 */
 813                commit->object.flags |= flag;
 814                if (commit->object.flags == flag)
 815                        insert_by_date(commit, &list);
 816                rev[num_rev] = commit;
 817        }
 818        for (i = 0; i < num_rev; i++)
 819                rev_mask[i] = rev[i]->object.flags;
 820
 821        if (0 <= extra)
 822                join_revs(&list, &seen, num_rev, extra);
 823
 824        sort_by_date(&seen);
 825
 826        if (merge_base)
 827                return show_merge_base(seen, num_rev);
 828
 829        if (independent)
 830                return show_independent(rev, num_rev, ref_name, rev_mask);
 831
 832        /* Show list; --more=-1 means list-only */
 833        if (1 < num_rev || extra < 0) {
 834                for (i = 0; i < num_rev; i++) {
 835                        int j;
 836                        int is_head = rev_is_head(head,
 837                                                  head_len,
 838                                                  ref_name[i],
 839                                                  head_sha1,
 840                                                  rev[i]->object.sha1);
 841                        if (extra < 0)
 842                                printf("%c [%s] ",
 843                                       is_head ? '*' : ' ', ref_name[i]);
 844                        else {
 845                                for (j = 0; j < i; j++)
 846                                        putchar(' ');
 847                                printf("%c [%s] ",
 848                                       is_head ? '*' : '!', ref_name[i]);
 849                        }
 850
 851                        if (!reflog) {
 852                                /* header lines never need name */
 853                                show_one_commit(rev[i], 1);
 854                        }
 855                        else
 856                                puts(reflog_msg[i]);
 857
 858                        if (is_head)
 859                                head_at = i;
 860                }
 861                if (0 <= extra) {
 862                        for (i = 0; i < num_rev; i++)
 863                                putchar('-');
 864                        putchar('\n');
 865                }
 866        }
 867        if (extra < 0)
 868                exit(0);
 869
 870        /* Sort topologically */
 871        sort_in_topological_order(&seen, lifo);
 872
 873        /* Give names to commits */
 874        if (!sha1_name && !no_name)
 875                name_commits(seen, rev, ref_name, num_rev);
 876
 877        all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 878        all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 879
 880        while (seen) {
 881                struct commit *commit = pop_one_commit(&seen);
 882                int this_flag = commit->object.flags;
 883                int is_merge_point = ((this_flag & all_revs) == all_revs);
 884
 885                shown_merge_point |= is_merge_point;
 886
 887                if (1 < num_rev) {
 888                        int is_merge = !!(commit->parents &&
 889                                          commit->parents->next);
 890                        if (topics &&
 891                            !is_merge_point &&
 892                            (this_flag & (1u << REV_SHIFT)))
 893                                continue;
 894                        if (dense && is_merge &&
 895                            omit_in_dense(commit, rev, num_rev))
 896                                continue;
 897                        for (i = 0; i < num_rev; i++) {
 898                                int mark;
 899                                if (!(this_flag & (1u << (i + REV_SHIFT))))
 900                                        mark = ' ';
 901                                else if (is_merge)
 902                                        mark = '-';
 903                                else if (i == head_at)
 904                                        mark = '*';
 905                                else
 906                                        mark = '+';
 907                                putchar(mark);
 908                        }
 909                        putchar(' ');
 910                }
 911                show_one_commit(commit, no_name);
 912
 913                if (shown_merge_point && --extra < 0)
 914                        break;
 915        }
 916        return 0;
 917}