builtin-show-branch.con commit pull --rebase: Avoid spurious conflicts and reapplying unnecessary patches (cf65426)
   1#include "cache.h"
   2#include "commit.h"
   3#include "refs.h"
   4#include "builtin.h"
   5#include "color.h"
   6#include "parse-options.h"
   7
   8static const char* show_branch_usage[] = {
   9    "git show-branch [-a|--all] [-r|--remotes] [--topo-order | --date-order] [--current] [--color | --no-color] [--sparse] [--more=<n> | --list | --independent | --merge-base] [--no-name | --sha1-name] [--topics] [<rev> | <glob>]...",
  10    "git show-branch (-g|--reflog)[=<n>[,<base>]] [--list] [<ref>]",
  11    NULL
  12};
  13
  14static int showbranch_use_color = -1;
  15static char column_colors[][COLOR_MAXLEN] = {
  16        GIT_COLOR_RED,
  17        GIT_COLOR_GREEN,
  18        GIT_COLOR_YELLOW,
  19        GIT_COLOR_BLUE,
  20        GIT_COLOR_MAGENTA,
  21        GIT_COLOR_CYAN,
  22};
  23
  24#define COLUMN_COLORS_MAX (ARRAY_SIZE(column_colors))
  25
  26static int default_num;
  27static int default_alloc;
  28static const char **default_arg;
  29
  30#define UNINTERESTING   01
  31
  32#define REV_SHIFT        2
  33#define MAX_REVS        (FLAG_BITS - REV_SHIFT) /* should not exceed bits_per_int - REV_SHIFT */
  34
  35#define DEFAULT_REFLOG  4
  36
  37static const char *get_color_code(int idx)
  38{
  39        if (showbranch_use_color)
  40                return column_colors[idx];
  41        return "";
  42}
  43
  44static const char *get_color_reset_code(void)
  45{
  46        if (showbranch_use_color)
  47                return GIT_COLOR_RESET;
  48        return "";
  49}
  50
  51static struct commit *interesting(struct commit_list *list)
  52{
  53        while (list) {
  54                struct commit *commit = list->item;
  55                list = list->next;
  56                if (commit->object.flags & UNINTERESTING)
  57                        continue;
  58                return commit;
  59        }
  60        return NULL;
  61}
  62
  63static struct commit *pop_one_commit(struct commit_list **list_p)
  64{
  65        struct commit *commit;
  66        struct commit_list *list;
  67        list = *list_p;
  68        commit = list->item;
  69        *list_p = list->next;
  70        free(list);
  71        return commit;
  72}
  73
  74struct commit_name {
  75        const char *head_name; /* which head's ancestor? */
  76        int generation; /* how many parents away from head_name */
  77};
  78
  79/* Name the commit as nth generation ancestor of head_name;
  80 * we count only the first-parent relationship for naming purposes.
  81 */
  82static void name_commit(struct commit *commit, const char *head_name, int nth)
  83{
  84        struct commit_name *name;
  85        if (!commit->util)
  86                commit->util = xmalloc(sizeof(struct commit_name));
  87        name = commit->util;
  88        name->head_name = head_name;
  89        name->generation = nth;
  90}
  91
  92/* Parent is the first parent of the commit.  We may name it
  93 * as (n+1)th generation ancestor of the same head_name as
  94 * commit is nth generation ancestor of, if that generation
  95 * number is better than the name it already has.
  96 */
  97static void name_parent(struct commit *commit, struct commit *parent)
  98{
  99        struct commit_name *commit_name = commit->util;
 100        struct commit_name *parent_name = parent->util;
 101        if (!commit_name)
 102                return;
 103        if (!parent_name ||
 104            commit_name->generation + 1 < parent_name->generation)
 105                name_commit(parent, commit_name->head_name,
 106                            commit_name->generation + 1);
 107}
 108
 109static int name_first_parent_chain(struct commit *c)
 110{
 111        int i = 0;
 112        while (c) {
 113                struct commit *p;
 114                if (!c->util)
 115                        break;
 116                if (!c->parents)
 117                        break;
 118                p = c->parents->item;
 119                if (!p->util) {
 120                        name_parent(c, p);
 121                        i++;
 122                }
 123                else
 124                        break;
 125                c = p;
 126        }
 127        return i;
 128}
 129
 130static void name_commits(struct commit_list *list,
 131                         struct commit **rev,
 132                         char **ref_name,
 133                         int num_rev)
 134{
 135        struct commit_list *cl;
 136        struct commit *c;
 137        int i;
 138
 139        /* First give names to the given heads */
 140        for (cl = list; cl; cl = cl->next) {
 141                c = cl->item;
 142                if (c->util)
 143                        continue;
 144                for (i = 0; i < num_rev; i++) {
 145                        if (rev[i] == c) {
 146                                name_commit(c, ref_name[i], 0);
 147                                break;
 148                        }
 149                }
 150        }
 151
 152        /* Then commits on the first parent ancestry chain */
 153        do {
 154                i = 0;
 155                for (cl = list; cl; cl = cl->next) {
 156                        i += name_first_parent_chain(cl->item);
 157                }
 158        } while (i);
 159
 160        /* Finally, any unnamed commits */
 161        do {
 162                i = 0;
 163                for (cl = list; cl; cl = cl->next) {
 164                        struct commit_list *parents;
 165                        struct commit_name *n;
 166                        int nth;
 167                        c = cl->item;
 168                        if (!c->util)
 169                                continue;
 170                        n = c->util;
 171                        parents = c->parents;
 172                        nth = 0;
 173                        while (parents) {
 174                                struct commit *p = parents->item;
 175                                char newname[1000], *en;
 176                                parents = parents->next;
 177                                nth++;
 178                                if (p->util)
 179                                        continue;
 180                                en = newname;
 181                                switch (n->generation) {
 182                                case 0:
 183                                        en += sprintf(en, "%s", n->head_name);
 184                                        break;
 185                                case 1:
 186                                        en += sprintf(en, "%s^", n->head_name);
 187                                        break;
 188                                default:
 189                                        en += sprintf(en, "%s~%d",
 190                                                n->head_name, n->generation);
 191                                        break;
 192                                }
 193                                if (nth == 1)
 194                                        en += sprintf(en, "^");
 195                                else
 196                                        en += sprintf(en, "^%d", nth);
 197                                name_commit(p, xstrdup(newname), 0);
 198                                i++;
 199                                name_first_parent_chain(p);
 200                        }
 201                }
 202        } while (i);
 203}
 204
 205static int mark_seen(struct commit *commit, struct commit_list **seen_p)
 206{
 207        if (!commit->object.flags) {
 208                commit_list_insert(commit, seen_p);
 209                return 1;
 210        }
 211        return 0;
 212}
 213
 214static void join_revs(struct commit_list **list_p,
 215                      struct commit_list **seen_p,
 216                      int num_rev, int extra)
 217{
 218        int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 219        int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 220
 221        while (*list_p) {
 222                struct commit_list *parents;
 223                int still_interesting = !!interesting(*list_p);
 224                struct commit *commit = pop_one_commit(list_p);
 225                int flags = commit->object.flags & all_mask;
 226
 227                if (!still_interesting && extra <= 0)
 228                        break;
 229
 230                mark_seen(commit, seen_p);
 231                if ((flags & all_revs) == all_revs)
 232                        flags |= UNINTERESTING;
 233                parents = commit->parents;
 234
 235                while (parents) {
 236                        struct commit *p = parents->item;
 237                        int this_flag = p->object.flags;
 238                        parents = parents->next;
 239                        if ((this_flag & flags) == flags)
 240                                continue;
 241                        if (!p->object.parsed)
 242                                parse_commit(p);
 243                        if (mark_seen(p, seen_p) && !still_interesting)
 244                                extra--;
 245                        p->object.flags |= flags;
 246                        insert_by_date(p, list_p);
 247                }
 248        }
 249
 250        /*
 251         * Postprocess to complete well-poisoning.
 252         *
 253         * At this point we have all the commits we have seen in
 254         * seen_p list.  Mark anything that can be reached from
 255         * uninteresting commits not interesting.
 256         */
 257        for (;;) {
 258                int changed = 0;
 259                struct commit_list *s;
 260                for (s = *seen_p; s; s = s->next) {
 261                        struct commit *c = s->item;
 262                        struct commit_list *parents;
 263
 264                        if (((c->object.flags & all_revs) != all_revs) &&
 265                            !(c->object.flags & UNINTERESTING))
 266                                continue;
 267
 268                        /* The current commit is either a merge base or
 269                         * already uninteresting one.  Mark its parents
 270                         * as uninteresting commits _only_ if they are
 271                         * already parsed.  No reason to find new ones
 272                         * here.
 273                         */
 274                        parents = c->parents;
 275                        while (parents) {
 276                                struct commit *p = parents->item;
 277                                parents = parents->next;
 278                                if (!(p->object.flags & UNINTERESTING)) {
 279                                        p->object.flags |= UNINTERESTING;
 280                                        changed = 1;
 281                                }
 282                        }
 283                }
 284                if (!changed)
 285                        break;
 286        }
 287}
 288
 289static void show_one_commit(struct commit *commit, int no_name)
 290{
 291        struct strbuf pretty = STRBUF_INIT;
 292        const char *pretty_str = "(unavailable)";
 293        struct commit_name *name = commit->util;
 294
 295        if (commit->object.parsed) {
 296                struct pretty_print_context ctx = {0};
 297                pretty_print_commit(CMIT_FMT_ONELINE, commit, &pretty, &ctx);
 298                pretty_str = pretty.buf;
 299        }
 300        if (!prefixcmp(pretty_str, "[PATCH] "))
 301                pretty_str += 8;
 302
 303        if (!no_name) {
 304                if (name && name->head_name) {
 305                        printf("[%s", name->head_name);
 306                        if (name->generation) {
 307                                if (name->generation == 1)
 308                                        printf("^");
 309                                else
 310                                        printf("~%d", name->generation);
 311                        }
 312                        printf("] ");
 313                }
 314                else
 315                        printf("[%s] ",
 316                               find_unique_abbrev(commit->object.sha1, 7));
 317        }
 318        puts(pretty_str);
 319        strbuf_release(&pretty);
 320}
 321
 322static char *ref_name[MAX_REVS + 1];
 323static int ref_name_cnt;
 324
 325static const char *find_digit_prefix(const char *s, int *v)
 326{
 327        const char *p;
 328        int ver;
 329        char ch;
 330
 331        for (p = s, ver = 0;
 332             '0' <= (ch = *p) && ch <= '9';
 333             p++)
 334                ver = ver * 10 + ch - '0';
 335        *v = ver;
 336        return p;
 337}
 338
 339
 340static int version_cmp(const char *a, const char *b)
 341{
 342        while (1) {
 343                int va, vb;
 344
 345                a = find_digit_prefix(a, &va);
 346                b = find_digit_prefix(b, &vb);
 347                if (va != vb)
 348                        return va - vb;
 349
 350                while (1) {
 351                        int ca = *a;
 352                        int cb = *b;
 353                        if ('0' <= ca && ca <= '9')
 354                                ca = 0;
 355                        if ('0' <= cb && cb <= '9')
 356                                cb = 0;
 357                        if (ca != cb)
 358                                return ca - cb;
 359                        if (!ca)
 360                                break;
 361                        a++;
 362                        b++;
 363                }
 364                if (!*a && !*b)
 365                        return 0;
 366        }
 367}
 368
 369static int compare_ref_name(const void *a_, const void *b_)
 370{
 371        const char * const*a = a_, * const*b = b_;
 372        return version_cmp(*a, *b);
 373}
 374
 375static void sort_ref_range(int bottom, int top)
 376{
 377        qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
 378              compare_ref_name);
 379}
 380
 381static int append_ref(const char *refname, const unsigned char *sha1,
 382                      int allow_dups)
 383{
 384        struct commit *commit = lookup_commit_reference_gently(sha1, 1);
 385        int i;
 386
 387        if (!commit)
 388                return 0;
 389
 390        if (!allow_dups) {
 391                /* Avoid adding the same thing twice */
 392                for (i = 0; i < ref_name_cnt; i++)
 393                        if (!strcmp(refname, ref_name[i]))
 394                                return 0;
 395        }
 396        if (MAX_REVS <= ref_name_cnt) {
 397                warning("ignoring %s; cannot handle more than %d refs",
 398                        refname, MAX_REVS);
 399                return 0;
 400        }
 401        ref_name[ref_name_cnt++] = xstrdup(refname);
 402        ref_name[ref_name_cnt] = NULL;
 403        return 0;
 404}
 405
 406static int append_head_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 407{
 408        unsigned char tmp[20];
 409        int ofs = 11;
 410        if (prefixcmp(refname, "refs/heads/"))
 411                return 0;
 412        /* If both heads/foo and tags/foo exists, get_sha1 would
 413         * get confused.
 414         */
 415        if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
 416                ofs = 5;
 417        return append_ref(refname + ofs, sha1, 0);
 418}
 419
 420static int append_remote_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 421{
 422        unsigned char tmp[20];
 423        int ofs = 13;
 424        if (prefixcmp(refname, "refs/remotes/"))
 425                return 0;
 426        /* If both heads/foo and tags/foo exists, get_sha1 would
 427         * get confused.
 428         */
 429        if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
 430                ofs = 5;
 431        return append_ref(refname + ofs, sha1, 0);
 432}
 433
 434static int append_tag_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 435{
 436        if (prefixcmp(refname, "refs/tags/"))
 437                return 0;
 438        return append_ref(refname + 5, sha1, 0);
 439}
 440
 441static const char *match_ref_pattern = NULL;
 442static int match_ref_slash = 0;
 443static int count_slash(const char *s)
 444{
 445        int cnt = 0;
 446        while (*s)
 447                if (*s++ == '/')
 448                        cnt++;
 449        return cnt;
 450}
 451
 452static int append_matching_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 453{
 454        /* we want to allow pattern hold/<asterisk> to show all
 455         * branches under refs/heads/hold/, and v0.99.9? to show
 456         * refs/tags/v0.99.9a and friends.
 457         */
 458        const char *tail;
 459        int slash = count_slash(refname);
 460        for (tail = refname; *tail && match_ref_slash < slash; )
 461                if (*tail++ == '/')
 462                        slash--;
 463        if (!*tail)
 464                return 0;
 465        if (fnmatch(match_ref_pattern, tail, 0))
 466                return 0;
 467        if (!prefixcmp(refname, "refs/heads/"))
 468                return append_head_ref(refname, sha1, flag, cb_data);
 469        if (!prefixcmp(refname, "refs/tags/"))
 470                return append_tag_ref(refname, sha1, flag, cb_data);
 471        return append_ref(refname, sha1, 0);
 472}
 473
 474static void snarf_refs(int head, int remotes)
 475{
 476        if (head) {
 477                int orig_cnt = ref_name_cnt;
 478                for_each_ref(append_head_ref, NULL);
 479                sort_ref_range(orig_cnt, ref_name_cnt);
 480        }
 481        if (remotes) {
 482                int orig_cnt = ref_name_cnt;
 483                for_each_ref(append_remote_ref, NULL);
 484                sort_ref_range(orig_cnt, ref_name_cnt);
 485        }
 486}
 487
 488static int rev_is_head(char *head, int headlen, char *name,
 489                       unsigned char *head_sha1, unsigned char *sha1)
 490{
 491        if ((!head[0]) ||
 492            (head_sha1 && sha1 && hashcmp(head_sha1, sha1)))
 493                return 0;
 494        if (!prefixcmp(head, "refs/heads/"))
 495                head += 11;
 496        if (!prefixcmp(name, "refs/heads/"))
 497                name += 11;
 498        else if (!prefixcmp(name, "heads/"))
 499                name += 6;
 500        return !strcmp(head, name);
 501}
 502
 503static int show_merge_base(struct commit_list *seen, int num_rev)
 504{
 505        int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 506        int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 507        int exit_status = 1;
 508
 509        while (seen) {
 510                struct commit *commit = pop_one_commit(&seen);
 511                int flags = commit->object.flags & all_mask;
 512                if (!(flags & UNINTERESTING) &&
 513                    ((flags & all_revs) == all_revs)) {
 514                        puts(sha1_to_hex(commit->object.sha1));
 515                        exit_status = 0;
 516                        commit->object.flags |= UNINTERESTING;
 517                }
 518        }
 519        return exit_status;
 520}
 521
 522static int show_independent(struct commit **rev,
 523                            int num_rev,
 524                            char **ref_name,
 525                            unsigned int *rev_mask)
 526{
 527        int i;
 528
 529        for (i = 0; i < num_rev; i++) {
 530                struct commit *commit = rev[i];
 531                unsigned int flag = rev_mask[i];
 532
 533                if (commit->object.flags == flag)
 534                        puts(sha1_to_hex(commit->object.sha1));
 535                commit->object.flags |= UNINTERESTING;
 536        }
 537        return 0;
 538}
 539
 540static void append_one_rev(const char *av)
 541{
 542        unsigned char revkey[20];
 543        if (!get_sha1(av, revkey)) {
 544                append_ref(av, revkey, 0);
 545                return;
 546        }
 547        if (strchr(av, '*') || strchr(av, '?') || strchr(av, '[')) {
 548                /* glob style match */
 549                int saved_matches = ref_name_cnt;
 550                match_ref_pattern = av;
 551                match_ref_slash = count_slash(av);
 552                for_each_ref(append_matching_ref, NULL);
 553                if (saved_matches == ref_name_cnt &&
 554                    ref_name_cnt < MAX_REVS)
 555                        error("no matching refs with %s", av);
 556                if (saved_matches + 1 < ref_name_cnt)
 557                        sort_ref_range(saved_matches, ref_name_cnt);
 558                return;
 559        }
 560        die("bad sha1 reference %s", av);
 561}
 562
 563static int git_show_branch_config(const char *var, const char *value, void *cb)
 564{
 565        if (!strcmp(var, "showbranch.default")) {
 566                if (!value)
 567                        return config_error_nonbool(var);
 568                /*
 569                 * default_arg is now passed to parse_options(), so we need to
 570                 * mimick the real argv a bit better.
 571                 */
 572                if (!default_num) {
 573                        default_alloc = 20;
 574                        default_arg = xcalloc(default_alloc, sizeof(*default_arg));
 575                        default_arg[default_num++] = "show-branch";
 576                } else if (default_alloc <= default_num + 1) {
 577                        default_alloc = default_alloc * 3 / 2 + 20;
 578                        default_arg = xrealloc(default_arg, sizeof *default_arg * default_alloc);
 579                }
 580                default_arg[default_num++] = xstrdup(value);
 581                default_arg[default_num] = NULL;
 582                return 0;
 583        }
 584
 585        if (!strcmp(var, "color.showbranch")) {
 586                showbranch_use_color = git_config_colorbool(var, value, -1);
 587                return 0;
 588        }
 589
 590        return git_color_default_config(var, value, cb);
 591}
 592
 593static int omit_in_dense(struct commit *commit, struct commit **rev, int n)
 594{
 595        /* If the commit is tip of the named branches, do not
 596         * omit it.
 597         * Otherwise, if it is a merge that is reachable from only one
 598         * tip, it is not that interesting.
 599         */
 600        int i, flag, count;
 601        for (i = 0; i < n; i++)
 602                if (rev[i] == commit)
 603                        return 0;
 604        flag = commit->object.flags;
 605        for (i = count = 0; i < n; i++) {
 606                if (flag & (1u << (i + REV_SHIFT)))
 607                        count++;
 608        }
 609        if (count == 1)
 610                return 1;
 611        return 0;
 612}
 613
 614static int reflog = 0;
 615
 616static int parse_reflog_param(const struct option *opt, const char *arg,
 617                              int unset)
 618{
 619        char *ep;
 620        const char **base = (const char **)opt->value;
 621        if (!arg)
 622                arg = "";
 623        reflog = strtoul(arg, &ep, 10);
 624        if (*ep == ',')
 625                *base = ep + 1;
 626        else if (*ep)
 627                return error("unrecognized reflog param '%s'", arg);
 628        else
 629                *base = NULL;
 630        if (reflog <= 0)
 631                reflog = DEFAULT_REFLOG;
 632        return 0;
 633}
 634
 635int cmd_show_branch(int ac, const char **av, const char *prefix)
 636{
 637        struct commit *rev[MAX_REVS], *commit;
 638        char *reflog_msg[MAX_REVS];
 639        struct commit_list *list = NULL, *seen = NULL;
 640        unsigned int rev_mask[MAX_REVS];
 641        int num_rev, i, extra = 0;
 642        int all_heads = 0, all_remotes = 0;
 643        int all_mask, all_revs;
 644        int lifo = 1;
 645        char head[128];
 646        const char *head_p;
 647        int head_len;
 648        unsigned char head_sha1[20];
 649        int merge_base = 0;
 650        int independent = 0;
 651        int no_name = 0;
 652        int sha1_name = 0;
 653        int shown_merge_point = 0;
 654        int with_current_branch = 0;
 655        int head_at = -1;
 656        int topics = 0;
 657        int dense = 1;
 658        const char *reflog_base = NULL;
 659        struct option builtin_show_branch_options[] = {
 660                OPT_BOOLEAN('a', "all", &all_heads,
 661                            "show remote-tracking and local branches"),
 662                OPT_BOOLEAN('r', "remotes", &all_remotes,
 663                            "show remote-tracking branches"),
 664                OPT_BOOLEAN(0, "color", &showbranch_use_color,
 665                            "color '*!+-' corresponding to the branch"),
 666                { OPTION_INTEGER, 0, "more", &extra, "n",
 667                            "show <n> more commits after the common ancestor",
 668                            PARSE_OPT_OPTARG, NULL, (intptr_t)1 },
 669                OPT_SET_INT(0, "list", &extra, "synonym to more=-1", -1),
 670                OPT_BOOLEAN(0, "no-name", &no_name, "suppress naming strings"),
 671                OPT_BOOLEAN(0, "current", &with_current_branch,
 672                            "include the current branch"),
 673                OPT_BOOLEAN(0, "sha1-name", &sha1_name,
 674                            "name commits with their object names"),
 675                OPT_BOOLEAN(0, "merge-base", &merge_base,
 676                            "show possible merge bases"),
 677                OPT_BOOLEAN(0, "independent", &independent,
 678                            "show refs unreachable from any other ref"),
 679                OPT_BOOLEAN(0, "topo-order", &lifo,
 680                            "show commits in topological order"),
 681                OPT_BOOLEAN(0, "topics", &topics,
 682                            "show only commits not on the first branch"),
 683                OPT_SET_INT(0, "sparse", &dense,
 684                            "show merges reachable from only one tip", 0),
 685                OPT_SET_INT(0, "date-order", &lifo,
 686                            "show commits where no parent comes before its "
 687                            "children", 0),
 688                { OPTION_CALLBACK, 'g', "reflog", &reflog_base, "<n>[,<base>]",
 689                            "show <n> most recent ref-log entries starting at "
 690                            "base",
 691                            PARSE_OPT_OPTARG | PARSE_OPT_LITERAL_ARGHELP,
 692                            parse_reflog_param },
 693                OPT_END()
 694        };
 695
 696        git_config(git_show_branch_config, NULL);
 697
 698        if (showbranch_use_color == -1)
 699                showbranch_use_color = git_use_color_default;
 700
 701        /* If nothing is specified, try the default first */
 702        if (ac == 1 && default_num) {
 703                ac = default_num;
 704                av = default_arg;
 705        }
 706
 707        ac = parse_options(ac, av, prefix, builtin_show_branch_options,
 708                           show_branch_usage, PARSE_OPT_STOP_AT_NON_OPTION);
 709        if (all_heads)
 710                all_remotes = 1;
 711
 712        if (extra || reflog) {
 713                /* "listing" mode is incompatible with
 714                 * independent nor merge-base modes.
 715                 */
 716                if (independent || merge_base)
 717                        usage_with_options(show_branch_usage,
 718                                           builtin_show_branch_options);
 719                if (reflog && ((0 < extra) || all_heads || all_remotes))
 720                        /*
 721                         * Asking for --more in reflog mode does not
 722                         * make sense.  --list is Ok.
 723                         *
 724                         * Also --all and --remotes do not make sense either.
 725                         */
 726                        die("--reflog is incompatible with --all, --remotes, "
 727                            "--independent or --merge-base");
 728        }
 729
 730        /* If nothing is specified, show all branches by default */
 731        if (ac + all_heads + all_remotes == 0)
 732                all_heads = 1;
 733
 734        if (reflog) {
 735                unsigned char sha1[20];
 736                char nth_desc[256];
 737                char *ref;
 738                int base = 0;
 739
 740                if (ac == 0) {
 741                        static const char *fake_av[2];
 742                        const char *refname;
 743
 744                        refname = resolve_ref("HEAD", sha1, 1, NULL);
 745                        fake_av[0] = xstrdup(refname);
 746                        fake_av[1] = NULL;
 747                        av = fake_av;
 748                        ac = 1;
 749                }
 750                if (ac != 1)
 751                        die("--reflog option needs one branch name");
 752
 753                if (MAX_REVS < reflog)
 754                        die("Only %d entries can be shown at one time.",
 755                            MAX_REVS);
 756                if (!dwim_ref(*av, strlen(*av), sha1, &ref))
 757                        die("No such ref %s", *av);
 758
 759                /* Has the base been specified? */
 760                if (reflog_base) {
 761                        char *ep;
 762                        base = strtoul(reflog_base, &ep, 10);
 763                        if (*ep) {
 764                                /* Ah, that is a date spec... */
 765                                unsigned long at;
 766                                at = approxidate(reflog_base);
 767                                read_ref_at(ref, at, -1, sha1, NULL,
 768                                            NULL, NULL, &base);
 769                        }
 770                }
 771
 772                for (i = 0; i < reflog; i++) {
 773                        char *logmsg, *m;
 774                        const char *msg;
 775                        unsigned long timestamp;
 776                        int tz;
 777
 778                        if (read_ref_at(ref, 0, base+i, sha1, &logmsg,
 779                                        &timestamp, &tz, NULL)) {
 780                                reflog = i;
 781                                break;
 782                        }
 783                        msg = strchr(logmsg, '\t');
 784                        if (!msg)
 785                                msg = "(none)";
 786                        else
 787                                msg++;
 788                        m = xmalloc(strlen(msg) + 200);
 789                        sprintf(m, "(%s) %s",
 790                                show_date(timestamp, tz, 1),
 791                                msg);
 792                        reflog_msg[i] = m;
 793                        free(logmsg);
 794                        sprintf(nth_desc, "%s@{%d}", *av, base+i);
 795                        append_ref(nth_desc, sha1, 1);
 796                }
 797        }
 798        else if (all_heads + all_remotes)
 799                snarf_refs(all_heads, all_remotes);
 800        else {
 801                while (0 < ac) {
 802                        append_one_rev(*av);
 803                        ac--; av++;
 804                }
 805        }
 806
 807        head_p = resolve_ref("HEAD", head_sha1, 1, NULL);
 808        if (head_p) {
 809                head_len = strlen(head_p);
 810                memcpy(head, head_p, head_len + 1);
 811        }
 812        else {
 813                head_len = 0;
 814                head[0] = 0;
 815        }
 816
 817        if (with_current_branch && head_p) {
 818                int has_head = 0;
 819                for (i = 0; !has_head && i < ref_name_cnt; i++) {
 820                        /* We are only interested in adding the branch
 821                         * HEAD points at.
 822                         */
 823                        if (rev_is_head(head,
 824                                        head_len,
 825                                        ref_name[i],
 826                                        head_sha1, NULL))
 827                                has_head++;
 828                }
 829                if (!has_head) {
 830                        int offset = !prefixcmp(head, "refs/heads/") ? 11 : 0;
 831                        append_one_rev(head + offset);
 832                }
 833        }
 834
 835        if (!ref_name_cnt) {
 836                fprintf(stderr, "No revs to be shown.\n");
 837                exit(0);
 838        }
 839
 840        for (num_rev = 0; ref_name[num_rev]; num_rev++) {
 841                unsigned char revkey[20];
 842                unsigned int flag = 1u << (num_rev + REV_SHIFT);
 843
 844                if (MAX_REVS <= num_rev)
 845                        die("cannot handle more than %d revs.", MAX_REVS);
 846                if (get_sha1(ref_name[num_rev], revkey))
 847                        die("'%s' is not a valid ref.", ref_name[num_rev]);
 848                commit = lookup_commit_reference(revkey);
 849                if (!commit)
 850                        die("cannot find commit %s (%s)",
 851                            ref_name[num_rev], revkey);
 852                parse_commit(commit);
 853                mark_seen(commit, &seen);
 854
 855                /* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
 856                 * and so on.  REV_SHIFT bits from bit 0 are used for
 857                 * internal bookkeeping.
 858                 */
 859                commit->object.flags |= flag;
 860                if (commit->object.flags == flag)
 861                        insert_by_date(commit, &list);
 862                rev[num_rev] = commit;
 863        }
 864        for (i = 0; i < num_rev; i++)
 865                rev_mask[i] = rev[i]->object.flags;
 866
 867        if (0 <= extra)
 868                join_revs(&list, &seen, num_rev, extra);
 869
 870        sort_by_date(&seen);
 871
 872        if (merge_base)
 873                return show_merge_base(seen, num_rev);
 874
 875        if (independent)
 876                return show_independent(rev, num_rev, ref_name, rev_mask);
 877
 878        /* Show list; --more=-1 means list-only */
 879        if (1 < num_rev || extra < 0) {
 880                for (i = 0; i < num_rev; i++) {
 881                        int j;
 882                        int is_head = rev_is_head(head,
 883                                                  head_len,
 884                                                  ref_name[i],
 885                                                  head_sha1,
 886                                                  rev[i]->object.sha1);
 887                        if (extra < 0)
 888                                printf("%c [%s] ",
 889                                       is_head ? '*' : ' ', ref_name[i]);
 890                        else {
 891                                for (j = 0; j < i; j++)
 892                                        putchar(' ');
 893                                printf("%s%c%s [%s] ",
 894                                       get_color_code(i % COLUMN_COLORS_MAX),
 895                                       is_head ? '*' : '!',
 896                                       get_color_reset_code(), ref_name[i]);
 897                        }
 898
 899                        if (!reflog) {
 900                                /* header lines never need name */
 901                                show_one_commit(rev[i], 1);
 902                        }
 903                        else
 904                                puts(reflog_msg[i]);
 905
 906                        if (is_head)
 907                                head_at = i;
 908                }
 909                if (0 <= extra) {
 910                        for (i = 0; i < num_rev; i++)
 911                                putchar('-');
 912                        putchar('\n');
 913                }
 914        }
 915        if (extra < 0)
 916                exit(0);
 917
 918        /* Sort topologically */
 919        sort_in_topological_order(&seen, lifo);
 920
 921        /* Give names to commits */
 922        if (!sha1_name && !no_name)
 923                name_commits(seen, rev, ref_name, num_rev);
 924
 925        all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
 926        all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
 927
 928        while (seen) {
 929                struct commit *commit = pop_one_commit(&seen);
 930                int this_flag = commit->object.flags;
 931                int is_merge_point = ((this_flag & all_revs) == all_revs);
 932
 933                shown_merge_point |= is_merge_point;
 934
 935                if (1 < num_rev) {
 936                        int is_merge = !!(commit->parents &&
 937                                          commit->parents->next);
 938                        if (topics &&
 939                            !is_merge_point &&
 940                            (this_flag & (1u << REV_SHIFT)))
 941                                continue;
 942                        if (dense && is_merge &&
 943                            omit_in_dense(commit, rev, num_rev))
 944                                continue;
 945                        for (i = 0; i < num_rev; i++) {
 946                                int mark;
 947                                if (!(this_flag & (1u << (i + REV_SHIFT))))
 948                                        mark = ' ';
 949                                else if (is_merge)
 950                                        mark = '-';
 951                                else if (i == head_at)
 952                                        mark = '*';
 953                                else
 954                                        mark = '+';
 955                                printf("%s%c%s",
 956                                       get_color_code(i % COLUMN_COLORS_MAX),
 957                                       mark, get_color_reset_code());
 958                        }
 959                        putchar(' ');
 960                }
 961                show_one_commit(commit, no_name);
 962
 963                if (shown_merge_point && --extra < 0)
 964                        break;
 965        }
 966        return 0;
 967}