builtin / rev-parse.con commit Merge branch 'jt/perf-updates' (228b787)
   1/*
   2 * rev-parse.c
   3 *
   4 * Copyright (C) Linus Torvalds, 2005
   5 */
   6#include "cache.h"
   7#include "commit.h"
   8#include "refs.h"
   9#include "quote.h"
  10#include "builtin.h"
  11#include "parse-options.h"
  12#include "diff.h"
  13#include "revision.h"
  14#include "split-index.h"
  15
  16#define DO_REVS         1
  17#define DO_NOREV        2
  18#define DO_FLAGS        4
  19#define DO_NONFLAGS     8
  20static int filter = ~0;
  21
  22static const char *def;
  23
  24#define NORMAL 0
  25#define REVERSED 1
  26static int show_type = NORMAL;
  27
  28#define SHOW_SYMBOLIC_ASIS 1
  29#define SHOW_SYMBOLIC_FULL 2
  30static int symbolic;
  31static int abbrev;
  32static int abbrev_ref;
  33static int abbrev_ref_strict;
  34static int output_sq;
  35
  36static int stuck_long;
  37static struct string_list *ref_excludes;
  38
  39/*
  40 * Some arguments are relevant "revision" arguments,
  41 * others are about output format or other details.
  42 * This sorts it all out.
  43 */
  44static int is_rev_argument(const char *arg)
  45{
  46        static const char *rev_args[] = {
  47                "--all",
  48                "--bisect",
  49                "--dense",
  50                "--branches=",
  51                "--branches",
  52                "--header",
  53                "--ignore-missing",
  54                "--max-age=",
  55                "--max-count=",
  56                "--min-age=",
  57                "--no-merges",
  58                "--min-parents=",
  59                "--no-min-parents",
  60                "--max-parents=",
  61                "--no-max-parents",
  62                "--objects",
  63                "--objects-edge",
  64                "--parents",
  65                "--pretty",
  66                "--remotes=",
  67                "--remotes",
  68                "--glob=",
  69                "--sparse",
  70                "--tags=",
  71                "--tags",
  72                "--topo-order",
  73                "--date-order",
  74                "--unpacked",
  75                NULL
  76        };
  77        const char **p = rev_args;
  78
  79        /* accept -<digit>, like traditional "head" */
  80        if ((*arg == '-') && isdigit(arg[1]))
  81                return 1;
  82
  83        for (;;) {
  84                const char *str = *p++;
  85                int len;
  86                if (!str)
  87                        return 0;
  88                len = strlen(str);
  89                if (!strcmp(arg, str) ||
  90                    (str[len-1] == '=' && !strncmp(arg, str, len)))
  91                        return 1;
  92        }
  93}
  94
  95/* Output argument as a string, either SQ or normal */
  96static void show(const char *arg)
  97{
  98        if (output_sq) {
  99                int sq = '\'', ch;
 100
 101                putchar(sq);
 102                while ((ch = *arg++)) {
 103                        if (ch == sq)
 104                                fputs("'\\'", stdout);
 105                        putchar(ch);
 106                }
 107                putchar(sq);
 108                putchar(' ');
 109        }
 110        else
 111                puts(arg);
 112}
 113
 114/* Like show(), but with a negation prefix according to type */
 115static void show_with_type(int type, const char *arg)
 116{
 117        if (type != show_type)
 118                putchar('^');
 119        show(arg);
 120}
 121
 122/* Output a revision, only if filter allows it */
 123static void show_rev(int type, const unsigned char *sha1, const char *name)
 124{
 125        if (!(filter & DO_REVS))
 126                return;
 127        def = NULL;
 128
 129        if ((symbolic || abbrev_ref) && name) {
 130                if (symbolic == SHOW_SYMBOLIC_FULL || abbrev_ref) {
 131                        unsigned char discard[20];
 132                        char *full;
 133
 134                        switch (dwim_ref(name, strlen(name), discard, &full)) {
 135                        case 0:
 136                                /*
 137                                 * Not found -- not a ref.  We could
 138                                 * emit "name" here, but symbolic-full
 139                                 * users are interested in finding the
 140                                 * refs spelled in full, and they would
 141                                 * need to filter non-refs if we did so.
 142                                 */
 143                                break;
 144                        case 1: /* happy */
 145                                if (abbrev_ref)
 146                                        full = shorten_unambiguous_ref(full,
 147                                                abbrev_ref_strict);
 148                                show_with_type(type, full);
 149                                break;
 150                        default: /* ambiguous */
 151                                error("refname '%s' is ambiguous", name);
 152                                break;
 153                        }
 154                        free(full);
 155                } else {
 156                        show_with_type(type, name);
 157                }
 158        }
 159        else if (abbrev)
 160                show_with_type(type, find_unique_abbrev(sha1, abbrev));
 161        else
 162                show_with_type(type, sha1_to_hex(sha1));
 163}
 164
 165/* Output a flag, only if filter allows it. */
 166static int show_flag(const char *arg)
 167{
 168        if (!(filter & DO_FLAGS))
 169                return 0;
 170        if (filter & (is_rev_argument(arg) ? DO_REVS : DO_NOREV)) {
 171                show(arg);
 172                return 1;
 173        }
 174        return 0;
 175}
 176
 177static int show_default(void)
 178{
 179        const char *s = def;
 180
 181        if (s) {
 182                unsigned char sha1[20];
 183
 184                def = NULL;
 185                if (!get_sha1(s, sha1)) {
 186                        show_rev(NORMAL, sha1, s);
 187                        return 1;
 188                }
 189        }
 190        return 0;
 191}
 192
 193static int show_reference(const char *refname, const struct object_id *oid, int flag, void *cb_data)
 194{
 195        if (ref_excluded(ref_excludes, refname))
 196                return 0;
 197        show_rev(NORMAL, oid->hash, refname);
 198        return 0;
 199}
 200
 201static int anti_reference(const char *refname, const struct object_id *oid, int flag, void *cb_data)
 202{
 203        show_rev(REVERSED, oid->hash, refname);
 204        return 0;
 205}
 206
 207static int show_abbrev(const unsigned char *sha1, void *cb_data)
 208{
 209        show_rev(NORMAL, sha1, NULL);
 210        return 0;
 211}
 212
 213static void show_datestring(const char *flag, const char *datestr)
 214{
 215        static char buffer[100];
 216
 217        /* date handling requires both flags and revs */
 218        if ((filter & (DO_FLAGS | DO_REVS)) != (DO_FLAGS | DO_REVS))
 219                return;
 220        snprintf(buffer, sizeof(buffer), "%s%lu", flag, approxidate(datestr));
 221        show(buffer);
 222}
 223
 224static int show_file(const char *arg, int output_prefix)
 225{
 226        show_default();
 227        if ((filter & (DO_NONFLAGS|DO_NOREV)) == (DO_NONFLAGS|DO_NOREV)) {
 228                if (output_prefix) {
 229                        const char *prefix = startup_info->prefix;
 230                        show(prefix_filename(prefix,
 231                                             prefix ? strlen(prefix) : 0,
 232                                             arg));
 233                } else
 234                        show(arg);
 235                return 1;
 236        }
 237        return 0;
 238}
 239
 240static int try_difference(const char *arg)
 241{
 242        char *dotdot;
 243        unsigned char sha1[20];
 244        unsigned char end[20];
 245        const char *next;
 246        const char *this;
 247        int symmetric;
 248        static const char head_by_default[] = "HEAD";
 249
 250        if (!(dotdot = strstr(arg, "..")))
 251                return 0;
 252        next = dotdot + 2;
 253        this = arg;
 254        symmetric = (*next == '.');
 255
 256        *dotdot = 0;
 257        next += symmetric;
 258
 259        if (!*next)
 260                next = head_by_default;
 261        if (dotdot == arg)
 262                this = head_by_default;
 263
 264        if (this == head_by_default && next == head_by_default &&
 265            !symmetric) {
 266                /*
 267                 * Just ".."?  That is not a range but the
 268                 * pathspec for the parent directory.
 269                 */
 270                *dotdot = '.';
 271                return 0;
 272        }
 273
 274        if (!get_sha1_committish(this, sha1) && !get_sha1_committish(next, end)) {
 275                show_rev(NORMAL, end, next);
 276                show_rev(symmetric ? NORMAL : REVERSED, sha1, this);
 277                if (symmetric) {
 278                        struct commit_list *exclude;
 279                        struct commit *a, *b;
 280                        a = lookup_commit_reference(sha1);
 281                        b = lookup_commit_reference(end);
 282                        exclude = get_merge_bases(a, b);
 283                        while (exclude) {
 284                                struct commit *commit = pop_commit(&exclude);
 285                                show_rev(REVERSED, commit->object.oid.hash, NULL);
 286                        }
 287                }
 288                *dotdot = '.';
 289                return 1;
 290        }
 291        *dotdot = '.';
 292        return 0;
 293}
 294
 295static int try_parent_shorthands(const char *arg)
 296{
 297        char *dotdot;
 298        unsigned char sha1[20];
 299        struct commit *commit;
 300        struct commit_list *parents;
 301        int parent_number;
 302        int include_rev = 0;
 303        int include_parents = 0;
 304        int exclude_parent = 0;
 305
 306        if ((dotdot = strstr(arg, "^!"))) {
 307                include_rev = 1;
 308                if (dotdot[2])
 309                        return 0;
 310        } else if ((dotdot = strstr(arg, "^@"))) {
 311                include_parents = 1;
 312                if (dotdot[2])
 313                        return 0;
 314        } else if ((dotdot = strstr(arg, "^-"))) {
 315                include_rev = 1;
 316                exclude_parent = 1;
 317
 318                if (dotdot[2]) {
 319                        char *end;
 320                        exclude_parent = strtoul(dotdot + 2, &end, 10);
 321                        if (*end != '\0' || !exclude_parent)
 322                                return 0;
 323                }
 324        } else
 325                return 0;
 326
 327        *dotdot = 0;
 328        if (get_sha1_committish(arg, sha1)) {
 329                *dotdot = '^';
 330                return 0;
 331        }
 332
 333        commit = lookup_commit_reference(sha1);
 334        if (exclude_parent &&
 335            exclude_parent > commit_list_count(commit->parents)) {
 336                *dotdot = '^';
 337                return 0;
 338        }
 339
 340        if (include_rev)
 341                show_rev(NORMAL, sha1, arg);
 342        for (parents = commit->parents, parent_number = 1;
 343             parents;
 344             parents = parents->next, parent_number++) {
 345                char *name = NULL;
 346
 347                if (exclude_parent && parent_number != exclude_parent)
 348                        continue;
 349
 350                if (symbolic)
 351                        name = xstrfmt("%s^%d", arg, parent_number);
 352                show_rev(include_parents ? NORMAL : REVERSED,
 353                         parents->item->object.oid.hash, name);
 354                free(name);
 355        }
 356
 357        *dotdot = '^';
 358        return 1;
 359}
 360
 361static int parseopt_dump(const struct option *o, const char *arg, int unset)
 362{
 363        struct strbuf *parsed = o->value;
 364        if (unset)
 365                strbuf_addf(parsed, " --no-%s", o->long_name);
 366        else if (o->short_name && (o->long_name == NULL || !stuck_long))
 367                strbuf_addf(parsed, " -%c", o->short_name);
 368        else
 369                strbuf_addf(parsed, " --%s", o->long_name);
 370        if (arg) {
 371                if (!stuck_long)
 372                        strbuf_addch(parsed, ' ');
 373                else if (o->long_name)
 374                        strbuf_addch(parsed, '=');
 375                sq_quote_buf(parsed, arg);
 376        }
 377        return 0;
 378}
 379
 380static const char *skipspaces(const char *s)
 381{
 382        while (isspace(*s))
 383                s++;
 384        return s;
 385}
 386
 387static int cmd_parseopt(int argc, const char **argv, const char *prefix)
 388{
 389        static int keep_dashdash = 0, stop_at_non_option = 0;
 390        static char const * const parseopt_usage[] = {
 391                N_("git rev-parse --parseopt [<options>] -- [<args>...]"),
 392                NULL
 393        };
 394        static struct option parseopt_opts[] = {
 395                OPT_BOOL(0, "keep-dashdash", &keep_dashdash,
 396                                        N_("keep the `--` passed as an arg")),
 397                OPT_BOOL(0, "stop-at-non-option", &stop_at_non_option,
 398                                        N_("stop parsing after the "
 399                                           "first non-option argument")),
 400                OPT_BOOL(0, "stuck-long", &stuck_long,
 401                                        N_("output in stuck long form")),
 402                OPT_END(),
 403        };
 404        static const char * const flag_chars = "*=?!";
 405
 406        struct strbuf sb = STRBUF_INIT, parsed = STRBUF_INIT;
 407        const char **usage = NULL;
 408        struct option *opts = NULL;
 409        int onb = 0, osz = 0, unb = 0, usz = 0;
 410
 411        strbuf_addstr(&parsed, "set --");
 412        argc = parse_options(argc, argv, prefix, parseopt_opts, parseopt_usage,
 413                             PARSE_OPT_KEEP_DASHDASH);
 414        if (argc < 1 || strcmp(argv[0], "--"))
 415                usage_with_options(parseopt_usage, parseopt_opts);
 416
 417        /* get the usage up to the first line with a -- on it */
 418        for (;;) {
 419                if (strbuf_getline(&sb, stdin) == EOF)
 420                        die("premature end of input");
 421                ALLOC_GROW(usage, unb + 1, usz);
 422                if (!strcmp("--", sb.buf)) {
 423                        if (unb < 1)
 424                                die("no usage string given before the `--' separator");
 425                        usage[unb] = NULL;
 426                        break;
 427                }
 428                usage[unb++] = strbuf_detach(&sb, NULL);
 429        }
 430
 431        /* parse: (<short>|<short>,<long>|<long>)[*=?!]*<arghint>? SP+ <help> */
 432        while (strbuf_getline(&sb, stdin) != EOF) {
 433                const char *s;
 434                const char *help;
 435                struct option *o;
 436
 437                if (!sb.len)
 438                        continue;
 439
 440                ALLOC_GROW(opts, onb + 1, osz);
 441                memset(opts + onb, 0, sizeof(opts[onb]));
 442
 443                o = &opts[onb++];
 444                help = strchr(sb.buf, ' ');
 445                if (!help || *sb.buf == ' ') {
 446                        o->type = OPTION_GROUP;
 447                        o->help = xstrdup(skipspaces(sb.buf));
 448                        continue;
 449                }
 450
 451                o->type = OPTION_CALLBACK;
 452                o->help = xstrdup(skipspaces(help));
 453                o->value = &parsed;
 454                o->flags = PARSE_OPT_NOARG;
 455                o->callback = &parseopt_dump;
 456
 457                /* name(s) */
 458                s = strpbrk(sb.buf, flag_chars);
 459                if (s == NULL)
 460                        s = help;
 461
 462                if (s - sb.buf == 1) /* short option only */
 463                        o->short_name = *sb.buf;
 464                else if (sb.buf[1] != ',') /* long option only */
 465                        o->long_name = xmemdupz(sb.buf, s - sb.buf);
 466                else {
 467                        o->short_name = *sb.buf;
 468                        o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
 469                }
 470
 471                /* flags */
 472                while (s < help) {
 473                        switch (*s++) {
 474                        case '=':
 475                                o->flags &= ~PARSE_OPT_NOARG;
 476                                continue;
 477                        case '?':
 478                                o->flags &= ~PARSE_OPT_NOARG;
 479                                o->flags |= PARSE_OPT_OPTARG;
 480                                continue;
 481                        case '!':
 482                                o->flags |= PARSE_OPT_NONEG;
 483                                continue;
 484                        case '*':
 485                                o->flags |= PARSE_OPT_HIDDEN;
 486                                continue;
 487                        }
 488                        s--;
 489                        break;
 490                }
 491
 492                if (s < help)
 493                        o->argh = xmemdupz(s, help - s);
 494        }
 495        strbuf_release(&sb);
 496
 497        /* put an OPT_END() */
 498        ALLOC_GROW(opts, onb + 1, osz);
 499        memset(opts + onb, 0, sizeof(opts[onb]));
 500        argc = parse_options(argc, argv, prefix, opts, usage,
 501                        (keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0) |
 502                        (stop_at_non_option ? PARSE_OPT_STOP_AT_NON_OPTION : 0) |
 503                        PARSE_OPT_SHELL_EVAL);
 504
 505        strbuf_addstr(&parsed, " --");
 506        sq_quote_argv(&parsed, argv, 0);
 507        puts(parsed.buf);
 508        return 0;
 509}
 510
 511static int cmd_sq_quote(int argc, const char **argv)
 512{
 513        struct strbuf buf = STRBUF_INIT;
 514
 515        if (argc)
 516                sq_quote_argv(&buf, argv, 0);
 517        printf("%s\n", buf.buf);
 518        strbuf_release(&buf);
 519
 520        return 0;
 521}
 522
 523static void die_no_single_rev(int quiet)
 524{
 525        if (quiet)
 526                exit(1);
 527        else
 528                die("Needed a single revision");
 529}
 530
 531static const char builtin_rev_parse_usage[] =
 532N_("git rev-parse --parseopt [<options>] -- [<args>...]\n"
 533   "   or: git rev-parse --sq-quote [<arg>...]\n"
 534   "   or: git rev-parse [<options>] [<arg>...]\n"
 535   "\n"
 536   "Run \"git rev-parse --parseopt -h\" for more information on the first usage.");
 537
 538int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 539{
 540        int i, as_is = 0, verify = 0, quiet = 0, revs_count = 0, type = 0;
 541        int did_repo_setup = 0;
 542        int has_dashdash = 0;
 543        int output_prefix = 0;
 544        unsigned char sha1[20];
 545        unsigned int flags = 0;
 546        const char *name = NULL;
 547        struct object_context unused;
 548        struct strbuf buf = STRBUF_INIT;
 549
 550        if (argc > 1 && !strcmp("--parseopt", argv[1]))
 551                return cmd_parseopt(argc - 1, argv + 1, prefix);
 552
 553        if (argc > 1 && !strcmp("--sq-quote", argv[1]))
 554                return cmd_sq_quote(argc - 2, argv + 2);
 555
 556        if (argc > 1 && !strcmp("-h", argv[1]))
 557                usage(builtin_rev_parse_usage);
 558
 559        for (i = 1; i < argc; i++) {
 560                if (!strcmp(argv[i], "--")) {
 561                        has_dashdash = 1;
 562                        break;
 563                }
 564        }
 565
 566        /* No options; just report on whether we're in a git repo or not. */
 567        if (argc == 1) {
 568                setup_git_directory();
 569                git_config(git_default_config, NULL);
 570                return 0;
 571        }
 572
 573        for (i = 1; i < argc; i++) {
 574                const char *arg = argv[i];
 575
 576                if (!strcmp(arg, "--local-env-vars")) {
 577                        int i;
 578                        for (i = 0; local_repo_env[i]; i++)
 579                                printf("%s\n", local_repo_env[i]);
 580                        continue;
 581                }
 582                if (!strcmp(arg, "--resolve-git-dir")) {
 583                        const char *gitdir = argv[++i];
 584                        if (!gitdir)
 585                                die("--resolve-git-dir requires an argument");
 586                        gitdir = resolve_gitdir(gitdir);
 587                        if (!gitdir)
 588                                die("not a gitdir '%s'", argv[i]);
 589                        puts(gitdir);
 590                        continue;
 591                }
 592
 593                /* The rest of the options require a git repository. */
 594                if (!did_repo_setup) {
 595                        prefix = setup_git_directory();
 596                        git_config(git_default_config, NULL);
 597                        did_repo_setup = 1;
 598                }
 599
 600                if (!strcmp(arg, "--git-path")) {
 601                        if (!argv[i + 1])
 602                                die("--git-path requires an argument");
 603                        strbuf_reset(&buf);
 604                        puts(relative_path(git_path("%s", argv[i + 1]),
 605                                           prefix, &buf));
 606                        i++;
 607                        continue;
 608                }
 609                if (as_is) {
 610                        if (show_file(arg, output_prefix) && as_is < 2)
 611                                verify_filename(prefix, arg, 0);
 612                        continue;
 613                }
 614                if (!strcmp(arg,"-n")) {
 615                        if (++i >= argc)
 616                                die("-n requires an argument");
 617                        if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
 618                                show(arg);
 619                                show(argv[i]);
 620                        }
 621                        continue;
 622                }
 623                if (starts_with(arg, "-n")) {
 624                        if ((filter & DO_FLAGS) && (filter & DO_REVS))
 625                                show(arg);
 626                        continue;
 627                }
 628
 629                if (*arg == '-') {
 630                        if (!strcmp(arg, "--")) {
 631                                as_is = 2;
 632                                /* Pass on the "--" if we show anything but files.. */
 633                                if (filter & (DO_FLAGS | DO_REVS))
 634                                        show_file(arg, 0);
 635                                continue;
 636                        }
 637                        if (!strcmp(arg, "--default")) {
 638                                def = argv[++i];
 639                                if (!def)
 640                                        die("--default requires an argument");
 641                                continue;
 642                        }
 643                        if (!strcmp(arg, "--prefix")) {
 644                                prefix = argv[++i];
 645                                if (!prefix)
 646                                        die("--prefix requires an argument");
 647                                startup_info->prefix = prefix;
 648                                output_prefix = 1;
 649                                continue;
 650                        }
 651                        if (!strcmp(arg, "--revs-only")) {
 652                                filter &= ~DO_NOREV;
 653                                continue;
 654                        }
 655                        if (!strcmp(arg, "--no-revs")) {
 656                                filter &= ~DO_REVS;
 657                                continue;
 658                        }
 659                        if (!strcmp(arg, "--flags")) {
 660                                filter &= ~DO_NONFLAGS;
 661                                continue;
 662                        }
 663                        if (!strcmp(arg, "--no-flags")) {
 664                                filter &= ~DO_FLAGS;
 665                                continue;
 666                        }
 667                        if (!strcmp(arg, "--verify")) {
 668                                filter &= ~(DO_FLAGS|DO_NOREV);
 669                                verify = 1;
 670                                continue;
 671                        }
 672                        if (!strcmp(arg, "--quiet") || !strcmp(arg, "-q")) {
 673                                quiet = 1;
 674                                flags |= GET_SHA1_QUIETLY;
 675                                continue;
 676                        }
 677                        if (!strcmp(arg, "--short") ||
 678                            starts_with(arg, "--short=")) {
 679                                filter &= ~(DO_FLAGS|DO_NOREV);
 680                                verify = 1;
 681                                abbrev = DEFAULT_ABBREV;
 682                                if (!arg[7])
 683                                        continue;
 684                                abbrev = strtoul(arg + 8, NULL, 10);
 685                                if (abbrev < MINIMUM_ABBREV)
 686                                        abbrev = MINIMUM_ABBREV;
 687                                else if (40 <= abbrev)
 688                                        abbrev = 40;
 689                                continue;
 690                        }
 691                        if (!strcmp(arg, "--sq")) {
 692                                output_sq = 1;
 693                                continue;
 694                        }
 695                        if (!strcmp(arg, "--not")) {
 696                                show_type ^= REVERSED;
 697                                continue;
 698                        }
 699                        if (!strcmp(arg, "--symbolic")) {
 700                                symbolic = SHOW_SYMBOLIC_ASIS;
 701                                continue;
 702                        }
 703                        if (!strcmp(arg, "--symbolic-full-name")) {
 704                                symbolic = SHOW_SYMBOLIC_FULL;
 705                                continue;
 706                        }
 707                        if (starts_with(arg, "--abbrev-ref") &&
 708                            (!arg[12] || arg[12] == '=')) {
 709                                abbrev_ref = 1;
 710                                abbrev_ref_strict = warn_ambiguous_refs;
 711                                if (arg[12] == '=') {
 712                                        if (!strcmp(arg + 13, "strict"))
 713                                                abbrev_ref_strict = 1;
 714                                        else if (!strcmp(arg + 13, "loose"))
 715                                                abbrev_ref_strict = 0;
 716                                        else
 717                                                die("unknown mode for %s", arg);
 718                                }
 719                                continue;
 720                        }
 721                        if (!strcmp(arg, "--all")) {
 722                                for_each_ref(show_reference, NULL);
 723                                continue;
 724                        }
 725                        if (starts_with(arg, "--disambiguate=")) {
 726                                for_each_abbrev(arg + 15, show_abbrev, NULL);
 727                                continue;
 728                        }
 729                        if (!strcmp(arg, "--bisect")) {
 730                                for_each_ref_in("refs/bisect/bad", show_reference, NULL);
 731                                for_each_ref_in("refs/bisect/good", anti_reference, NULL);
 732                                continue;
 733                        }
 734                        if (starts_with(arg, "--branches=")) {
 735                                for_each_glob_ref_in(show_reference, arg + 11,
 736                                        "refs/heads/", NULL);
 737                                clear_ref_exclusion(&ref_excludes);
 738                                continue;
 739                        }
 740                        if (!strcmp(arg, "--branches")) {
 741                                for_each_branch_ref(show_reference, NULL);
 742                                clear_ref_exclusion(&ref_excludes);
 743                                continue;
 744                        }
 745                        if (starts_with(arg, "--tags=")) {
 746                                for_each_glob_ref_in(show_reference, arg + 7,
 747                                        "refs/tags/", NULL);
 748                                clear_ref_exclusion(&ref_excludes);
 749                                continue;
 750                        }
 751                        if (!strcmp(arg, "--tags")) {
 752                                for_each_tag_ref(show_reference, NULL);
 753                                clear_ref_exclusion(&ref_excludes);
 754                                continue;
 755                        }
 756                        if (starts_with(arg, "--glob=")) {
 757                                for_each_glob_ref(show_reference, arg + 7, NULL);
 758                                clear_ref_exclusion(&ref_excludes);
 759                                continue;
 760                        }
 761                        if (starts_with(arg, "--remotes=")) {
 762                                for_each_glob_ref_in(show_reference, arg + 10,
 763                                        "refs/remotes/", NULL);
 764                                clear_ref_exclusion(&ref_excludes);
 765                                continue;
 766                        }
 767                        if (!strcmp(arg, "--remotes")) {
 768                                for_each_remote_ref(show_reference, NULL);
 769                                clear_ref_exclusion(&ref_excludes);
 770                                continue;
 771                        }
 772                        if (starts_with(arg, "--exclude=")) {
 773                                add_ref_exclusion(&ref_excludes, arg + 10);
 774                                continue;
 775                        }
 776                        if (!strcmp(arg, "--show-toplevel")) {
 777                                const char *work_tree = get_git_work_tree();
 778                                if (work_tree)
 779                                        puts(work_tree);
 780                                continue;
 781                        }
 782                        if (!strcmp(arg, "--show-prefix")) {
 783                                if (prefix)
 784                                        puts(prefix);
 785                                else
 786                                        putchar('\n');
 787                                continue;
 788                        }
 789                        if (!strcmp(arg, "--show-cdup")) {
 790                                const char *pfx = prefix;
 791                                if (!is_inside_work_tree()) {
 792                                        const char *work_tree =
 793                                                get_git_work_tree();
 794                                        if (work_tree)
 795                                                printf("%s\n", work_tree);
 796                                        continue;
 797                                }
 798                                while (pfx) {
 799                                        pfx = strchr(pfx, '/');
 800                                        if (pfx) {
 801                                                pfx++;
 802                                                printf("../");
 803                                        }
 804                                }
 805                                putchar('\n');
 806                                continue;
 807                        }
 808                        if (!strcmp(arg, "--git-dir") ||
 809                            !strcmp(arg, "--absolute-git-dir")) {
 810                                const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
 811                                char *cwd;
 812                                int len;
 813                                if (arg[2] == 'g') {    /* --git-dir */
 814                                        if (gitdir) {
 815                                                puts(gitdir);
 816                                                continue;
 817                                        }
 818                                        if (!prefix) {
 819                                                puts(".git");
 820                                                continue;
 821                                        }
 822                                } else {                /* --absolute-git-dir */
 823                                        if (!gitdir && !prefix)
 824                                                gitdir = ".git";
 825                                        if (gitdir) {
 826                                                puts(real_path(gitdir));
 827                                                continue;
 828                                        }
 829                                }
 830                                cwd = xgetcwd();
 831                                len = strlen(cwd);
 832                                printf("%s%s.git\n", cwd, len && cwd[len-1] != '/' ? "/" : "");
 833                                free(cwd);
 834                                continue;
 835                        }
 836                        if (!strcmp(arg, "--git-common-dir")) {
 837                                strbuf_reset(&buf);
 838                                puts(relative_path(get_git_common_dir(),
 839                                                   prefix, &buf));
 840                                continue;
 841                        }
 842                        if (!strcmp(arg, "--is-inside-git-dir")) {
 843                                printf("%s\n", is_inside_git_dir() ? "true"
 844                                                : "false");
 845                                continue;
 846                        }
 847                        if (!strcmp(arg, "--is-inside-work-tree")) {
 848                                printf("%s\n", is_inside_work_tree() ? "true"
 849                                                : "false");
 850                                continue;
 851                        }
 852                        if (!strcmp(arg, "--is-bare-repository")) {
 853                                printf("%s\n", is_bare_repository() ? "true"
 854                                                : "false");
 855                                continue;
 856                        }
 857                        if (!strcmp(arg, "--shared-index-path")) {
 858                                if (read_cache() < 0)
 859                                        die(_("Could not read the index"));
 860                                if (the_index.split_index) {
 861                                        const unsigned char *sha1 = the_index.split_index->base_sha1;
 862                                        const char *path = git_path("sharedindex.%s", sha1_to_hex(sha1));
 863                                        strbuf_reset(&buf);
 864                                        puts(relative_path(path, prefix, &buf));
 865                                }
 866                                continue;
 867                        }
 868                        if (starts_with(arg, "--since=")) {
 869                                show_datestring("--max-age=", arg+8);
 870                                continue;
 871                        }
 872                        if (starts_with(arg, "--after=")) {
 873                                show_datestring("--max-age=", arg+8);
 874                                continue;
 875                        }
 876                        if (starts_with(arg, "--before=")) {
 877                                show_datestring("--min-age=", arg+9);
 878                                continue;
 879                        }
 880                        if (starts_with(arg, "--until=")) {
 881                                show_datestring("--min-age=", arg+8);
 882                                continue;
 883                        }
 884                        if (show_flag(arg) && verify)
 885                                die_no_single_rev(quiet);
 886                        continue;
 887                }
 888
 889                /* Not a flag argument */
 890                if (try_difference(arg))
 891                        continue;
 892                if (try_parent_shorthands(arg))
 893                        continue;
 894                name = arg;
 895                type = NORMAL;
 896                if (*arg == '^') {
 897                        name++;
 898                        type = REVERSED;
 899                }
 900                if (!get_sha1_with_context(name, flags, sha1, &unused)) {
 901                        if (verify)
 902                                revs_count++;
 903                        else
 904                                show_rev(type, sha1, name);
 905                        continue;
 906                }
 907                if (verify)
 908                        die_no_single_rev(quiet);
 909                if (has_dashdash)
 910                        die("bad revision '%s'", arg);
 911                as_is = 1;
 912                if (!show_file(arg, output_prefix))
 913                        continue;
 914                verify_filename(prefix, arg, 1);
 915        }
 916        strbuf_release(&buf);
 917        if (verify) {
 918                if (revs_count == 1) {
 919                        show_rev(type, sha1, name);
 920                        return 0;
 921                } else if (revs_count == 0 && show_default())
 922                        return 0;
 923                die_no_single_rev(quiet);
 924        } else
 925                show_default();
 926        return 0;
 927}