Andrew's git - gitweb.git/blob - builtin/rev-parse.c

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