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 #include "split-index.h"
  15 #include "submodule.h"
  16
  17 #define DO_REVS         1
  18 #define DO_NOREV        2
  19 #define DO_FLAGS        4
  20 #define DO_NONFLAGS     8
  21 static int filter = ~0;
  22
  23 static const char *def;
  24
  25 #define NORMAL 0
  26 #define REVERSED 1
  27 static int show_type = NORMAL;
  28
  29 #define SHOW_SYMBOLIC_ASIS 1
  30 #define SHOW_SYMBOLIC_FULL 2
  31 static int symbolic;
  32 static int abbrev;
  33 static int abbrev_ref;
  34 static int abbrev_ref_strict;
  35 static int output_sq;
  36
  37 static int stuck_long;
  38 static struct string_list *ref_excludes;
  39
  40 /*
  41  * Some arguments are relevant "revision" arguments,
  42  * others are about output format or other details.
  43  * This sorts it all out.
  44  */
  45 static int is_rev_argument(const char *arg)
  46 {
  47         static const char *rev_args[] = {
  48                 "--all",
  49                 "--bisect",
  50                 "--dense",
  51                 "--branches=",
  52                 "--branches",
  53                 "--header",
  54                 "--ignore-missing",
  55                 "--max-age=",
  56                 "--max-count=",
  57                 "--min-age=",
  58                 "--no-merges",
  59                 "--min-parents=",
  60                 "--no-min-parents",
  61                 "--max-parents=",
  62                 "--no-max-parents",
  63                 "--objects",
  64                 "--objects-edge",
  65                 "--parents",
  66                 "--pretty",
  67                 "--remotes=",
  68                 "--remotes",
  69                 "--glob=",
  70                 "--sparse",
  71                 "--tags=",
  72                 "--tags",
  73                 "--topo-order",
  74                 "--date-order",
  75                 "--unpacked",
  76                 NULL
  77         };
  78         const char **p = rev_args;
  79
  80         /* accept -<digit>, like traditional "head" */
  81         if ((*arg == '-') && isdigit(arg[1]))
  82                 return 1;
  83
  84         for (;;) {
  85                 const char *str = *p++;
  86                 int len;
  87                 if (!str)
  88                         return 0;
  89                 len = strlen(str);
  90                 if (!strcmp(arg, str) ||
  91                     (str[len-1] == '=' && !strncmp(arg, str, len)))
  92                         return 1;
  93         }
  94 }
  95
  96 /* Output argument as a string, either SQ or normal */
  97 static void show(const char *arg)
  98 {
  99         if (output_sq) {
 100                 int sq = '\'', ch;
 101
 102                 putchar(sq);
 103                 while ((ch = *arg++)) {
 104                         if (ch == sq)
 105                                 fputs("'\\'", stdout);
 106                         putchar(ch);
 107                 }
 108                 putchar(sq);
 109                 putchar(' ');
 110         }
 111         else
 112                 puts(arg);
 113 }
 114
 115 /* Like show(), but with a negation prefix according to type */
 116 static void show_with_type(int type, const char *arg)
 117 {
 118         if (type != show_type)
 119                 putchar('^');
 120         show(arg);
 121 }
 122
 123 /* Output a revision, only if filter allows it */
 124 static void show_rev(int type, const unsigned char *sha1, const char *name)
 125 {
 126         if (!(filter & DO_REVS))
 127                 return;
 128         def = NULL;
 129
 130         if ((symbolic || abbrev_ref) && name) {
 131                 if (symbolic == SHOW_SYMBOLIC_FULL || abbrev_ref) {
 132                         unsigned char discard[20];
 133                         char *full;
 134
 135                         switch (dwim_ref(name, strlen(name), discard, &full)) {
 136                         case 0:
 137                                 /*
 138                                  * Not found -- not a ref.  We could
 139                                  * emit "name" here, but symbolic-full
 140                                  * users are interested in finding the
 141                                  * refs spelled in full, and they would
 142                                  * need to filter non-refs if we did so.
 143                                  */
 144                                 break;
 145                         case 1: /* happy */
 146                                 if (abbrev_ref)
 147                                         full = shorten_unambiguous_ref(full,
 148                                                 abbrev_ref_strict);
 149                                 show_with_type(type, full);
 150                                 break;
 151                         default: /* ambiguous */
 152                                 error("refname '%s' is ambiguous", name);
 153                                 break;
 154                         }
 155                         free(full);
 156                 } else {
 157                         show_with_type(type, name);
 158                 }
 159         }
 160         else if (abbrev)
 161                 show_with_type(type, find_unique_abbrev(sha1, abbrev));
 162         else
 163                 show_with_type(type, sha1_to_hex(sha1));
 164 }
 165
 166 /* Output a flag, only if filter allows it. */
 167 static int show_flag(const char *arg)
 168 {
 169         if (!(filter & DO_FLAGS))
 170                 return 0;
 171         if (filter & (is_rev_argument(arg) ? DO_REVS : DO_NOREV)) {
 172                 show(arg);
 173                 return 1;
 174         }
 175         return 0;
 176 }
 177
 178 static int show_default(void)
 179 {
 180         const char *s = def;
 181
 182         if (s) {
 183                 unsigned char sha1[20];
 184
 185                 def = NULL;
 186                 if (!get_sha1(s, sha1)) {
 187                         show_rev(NORMAL, sha1, s);
 188                         return 1;
 189                 }
 190         }
 191         return 0;
 192 }
 193
 194 static int show_reference(const char *refname, const struct object_id *oid, int flag, void *cb_data)
 195 {
 196         if (ref_excluded(ref_excludes, refname))
 197                 return 0;
 198         show_rev(NORMAL, oid->hash, refname);
 199         return 0;
 200 }
 201
 202 static int anti_reference(const char *refname, const struct object_id *oid, int flag, void *cb_data)
 203 {
 204         show_rev(REVERSED, oid->hash, refname);
 205         return 0;
 206 }
 207
 208 static int show_abbrev(const unsigned char *sha1, void *cb_data)
 209 {
 210         show_rev(NORMAL, sha1, NULL);
 211         return 0;
 212 }
 213
 214 static void show_datestring(const char *flag, const char *datestr)
 215 {
 216         static char buffer[100];
 217
 218         /* date handling requires both flags and revs */
 219         if ((filter & (DO_FLAGS | DO_REVS)) != (DO_FLAGS | DO_REVS))
 220                 return;
 221         snprintf(buffer, sizeof(buffer), "%s%lu", flag, approxidate(datestr));
 222         show(buffer);
 223 }
 224
 225 static int show_file(const char *arg, int output_prefix)
 226 {
 227         show_default();
 228         if ((filter & (DO_NONFLAGS|DO_NOREV)) == (DO_NONFLAGS|DO_NOREV)) {
 229                 if (output_prefix) {
 230                         const char *prefix = startup_info->prefix;
 231                         show(prefix_filename(prefix, arg));
 232                 } else
 233                         show(arg);
 234                 return 1;
 235         }
 236         return 0;
 237 }
 238
 239 static int try_difference(const char *arg)
 240 {
 241         char *dotdot;
 242         unsigned char sha1[20];
 243         unsigned char end[20];
 244         const char *next;
 245         const char *this;
 246         int symmetric;
 247         static const char head_by_default[] = "HEAD";
 248
 249         if (!(dotdot = strstr(arg, "..")))
 250                 return 0;
 251         next = dotdot + 2;
 252         this = arg;
 253         symmetric = (*next == '.');
 254
 255         *dotdot = 0;
 256         next += symmetric;
 257
 258         if (!*next)
 259                 next = head_by_default;
 260         if (dotdot == arg)
 261                 this = head_by_default;
 262
 263         if (this == head_by_default && next == head_by_default &&
 264             !symmetric) {
 265                 /*
 266                  * Just ".."?  That is not a range but the
 267                  * pathspec for the parent directory.
 268                  */
 269                 *dotdot = '.';
 270                 return 0;
 271         }
 272
 273         if (!get_sha1_committish(this, sha1) && !get_sha1_committish(next, end)) {
 274                 show_rev(NORMAL, end, next);
 275                 show_rev(symmetric ? NORMAL : REVERSED, sha1, this);
 276                 if (symmetric) {
 277                         struct commit_list *exclude;
 278                         struct commit *a, *b;
 279                         a = lookup_commit_reference(sha1);
 280                         b = lookup_commit_reference(end);
 281                         exclude = get_merge_bases(a, b);
 282                         while (exclude) {
 283                                 struct commit *commit = pop_commit(&exclude);
 284                                 show_rev(REVERSED, commit->object.oid.hash, NULL);
 285                         }
 286                 }
 287                 *dotdot = '.';
 288                 return 1;
 289         }
 290         *dotdot = '.';
 291         return 0;
 292 }
 293
 294 static int try_parent_shorthands(const char *arg)
 295 {
 296         char *dotdot;
 297         unsigned char sha1[20];
 298         struct commit *commit;
 299         struct commit_list *parents;
 300         int parent_number;
 301         int include_rev = 0;
 302         int include_parents = 0;
 303         int exclude_parent = 0;
 304
 305         if ((dotdot = strstr(arg, "^!"))) {
 306                 include_rev = 1;
 307                 if (dotdot[2])
 308                         return 0;
 309         } else if ((dotdot = strstr(arg, "^@"))) {
 310                 include_parents = 1;
 311                 if (dotdot[2])
 312                         return 0;
 313         } else if ((dotdot = strstr(arg, "^-"))) {
 314                 include_rev = 1;
 315                 exclude_parent = 1;
 316
 317                 if (dotdot[2]) {
 318                         char *end;
 319                         exclude_parent = strtoul(dotdot + 2, &end, 10);
 320                         if (*end != '\0' || !exclude_parent)
 321                                 return 0;
 322                 }
 323         } else
 324                 return 0;
 325
 326         *dotdot = 0;
 327         if (get_sha1_committish(arg, sha1)) {
 328                 *dotdot = '^';
 329                 return 0;
 330         }
 331
 332         commit = lookup_commit_reference(sha1);
 333         if (exclude_parent &&
 334             exclude_parent > commit_list_count(commit->parents)) {
 335                 *dotdot = '^';
 336                 return 0;
 337         }
 338
 339         if (include_rev)
 340                 show_rev(NORMAL, sha1, arg);
 341         for (parents = commit->parents, parent_number = 1;
 342              parents;
 343              parents = parents->next, parent_number++) {
 344                 char *name = NULL;
 345
 346                 if (exclude_parent && parent_number != exclude_parent)
 347                         continue;
 348
 349                 if (symbolic)
 350                         name = xstrfmt("%s^%d", arg, parent_number);
 351                 show_rev(include_parents ? NORMAL : REVERSED,
 352                          parents->item->object.oid.hash, name);
 353                 free(name);
 354         }
 355
 356         *dotdot = '^';
 357         return 1;
 358 }
 359
 360 static int parseopt_dump(const struct option *o, const char *arg, int unset)
 361 {
 362         struct strbuf *parsed = o->value;
 363         if (unset)
 364                 strbuf_addf(parsed, " --no-%s", o->long_name);
 365         else if (o->short_name && (o->long_name == NULL || !stuck_long))
 366                 strbuf_addf(parsed, " -%c", o->short_name);
 367         else
 368                 strbuf_addf(parsed, " --%s", o->long_name);
 369         if (arg) {
 370                 if (!stuck_long)
 371                         strbuf_addch(parsed, ' ');
 372                 else if (o->long_name)
 373                         strbuf_addch(parsed, '=');
 374                 sq_quote_buf(parsed, arg);
 375         }
 376         return 0;
 377 }
 378
 379 static const char *skipspaces(const char *s)
 380 {
 381         while (isspace(*s))
 382                 s++;
 383         return s;
 384 }
 385
 386 static int cmd_parseopt(int argc, const char **argv, const char *prefix)
 387 {
 388         static int keep_dashdash = 0, stop_at_non_option = 0;
 389         static char const * const parseopt_usage[] = {
 390                 N_("git rev-parse --parseopt [<options>] -- [<args>...]"),
 391                 NULL
 392         };
 393         static struct option parseopt_opts[] = {
 394                 OPT_BOOL(0, "keep-dashdash", &keep_dashdash,
 395                                         N_("keep the `--` passed as an arg")),
 396                 OPT_BOOL(0, "stop-at-non-option", &stop_at_non_option,
 397                                         N_("stop parsing after the "
 398                                            "first non-option argument")),
 399                 OPT_BOOL(0, "stuck-long", &stuck_long,
 400                                         N_("output in stuck long form")),
 401                 OPT_END(),
 402         };
 403         static const char * const flag_chars = "*=?!";
 404
 405         struct strbuf sb = STRBUF_INIT, parsed = STRBUF_INIT;
 406         const char **usage = NULL;
 407         struct option *opts = NULL;
 408         int onb = 0, osz = 0, unb = 0, usz = 0;
 409
 410         strbuf_addstr(&parsed, "set --");
 411         argc = parse_options(argc, argv, prefix, parseopt_opts, parseopt_usage,
 412                              PARSE_OPT_KEEP_DASHDASH);
 413         if (argc < 1 || strcmp(argv[0], "--"))
 414                 usage_with_options(parseopt_usage, parseopt_opts);
 415
 416         /* get the usage up to the first line with a -- on it */
 417         for (;;) {
 418                 if (strbuf_getline(&sb, stdin) == EOF)
 419                         die("premature end of input");
 420                 ALLOC_GROW(usage, unb + 1, usz);
 421                 if (!strcmp("--", sb.buf)) {
 422                         if (unb < 1)
 423                                 die("no usage string given before the `--' separator");
 424                         usage[unb] = NULL;
 425                         break;
 426                 }
 427                 usage[unb++] = strbuf_detach(&sb, NULL);
 428         }
 429
 430         /* parse: (<short>|<short>,<long>|<long>)[*=?!]*<arghint>? SP+ <help> */
 431         while (strbuf_getline(&sb, stdin) != EOF) {
 432                 const char *s;
 433                 const char *help;
 434                 struct option *o;
 435
 436                 if (!sb.len)
 437                         continue;
 438
 439                 ALLOC_GROW(opts, onb + 1, osz);
 440                 memset(opts + onb, 0, sizeof(opts[onb]));
 441
 442                 o = &opts[onb++];
 443                 help = strchr(sb.buf, ' ');
 444                 if (!help || *sb.buf == ' ') {
 445                         o->type = OPTION_GROUP;
 446                         o->help = xstrdup(skipspaces(sb.buf));
 447                         continue;
 448                 }
 449
 450                 o->type = OPTION_CALLBACK;
 451                 o->help = xstrdup(skipspaces(help));
 452                 o->value = &parsed;
 453                 o->flags = PARSE_OPT_NOARG;
 454                 o->callback = &parseopt_dump;
 455
 456                 /* name(s) */
 457                 s = strpbrk(sb.buf, flag_chars);
 458                 if (s == NULL)
 459                         s = help;
 460
 461                 if (s - sb.buf == 1) /* short option only */
 462                         o->short_name = *sb.buf;
 463                 else if (sb.buf[1] != ',') /* long option only */
 464                         o->long_name = xmemdupz(sb.buf, s - sb.buf);
 465                 else {
 466                         o->short_name = *sb.buf;
 467                         o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
 468                 }
 469
 470                 /* flags */
 471                 while (s < help) {
 472                         switch (*s++) {
 473                         case '=':
 474                                 o->flags &= ~PARSE_OPT_NOARG;
 475                                 continue;
 476                         case '?':
 477                                 o->flags &= ~PARSE_OPT_NOARG;
 478                                 o->flags |= PARSE_OPT_OPTARG;
 479                                 continue;
 480                         case '!':
 481                                 o->flags |= PARSE_OPT_NONEG;
 482                                 continue;
 483                         case '*':
 484                                 o->flags |= PARSE_OPT_HIDDEN;
 485                                 continue;
 486                         }
 487                         s--;
 488                         break;
 489                 }
 490
 491                 if (s < help)
 492                         o->argh = xmemdupz(s, help - s);
 493         }
 494         strbuf_release(&sb);
 495
 496         /* put an OPT_END() */
 497         ALLOC_GROW(opts, onb + 1, osz);
 498         memset(opts + onb, 0, sizeof(opts[onb]));
 499         argc = parse_options(argc, argv, prefix, opts, usage,
 500                         (keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0) |
 501                         (stop_at_non_option ? PARSE_OPT_STOP_AT_NON_OPTION : 0) |
 502                         PARSE_OPT_SHELL_EVAL);
 503
 504         strbuf_addstr(&parsed, " --");
 505         sq_quote_argv(&parsed, argv, 0);
 506         puts(parsed.buf);
 507         return 0;
 508 }
 509
 510 static int cmd_sq_quote(int argc, const char **argv)
 511 {
 512         struct strbuf buf = STRBUF_INIT;
 513
 514         if (argc)
 515                 sq_quote_argv(&buf, argv, 0);
 516         printf("%s\n", buf.buf);
 517         strbuf_release(&buf);
 518
 519         return 0;
 520 }
 521
 522 static void die_no_single_rev(int quiet)
 523 {
 524         if (quiet)
 525                 exit(1);
 526         else
 527                 die("Needed a single revision");
 528 }
 529
 530 static const char builtin_rev_parse_usage[] =
 531 N_("git rev-parse --parseopt [<options>] -- [<args>...]\n"
 532    "   or: git rev-parse --sq-quote [<arg>...]\n"
 533    "   or: git rev-parse [<options>] [<arg>...]\n"
 534    "\n"
 535    "Run \"git rev-parse --parseopt -h\" for more information on the first usage.");
 536
 537 int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 538 {
 539         int i, as_is = 0, verify = 0, quiet = 0, revs_count = 0, type = 0;
 540         int did_repo_setup = 0;
 541         int has_dashdash = 0;
 542         int output_prefix = 0;
 543         unsigned char sha1[20];
 544         unsigned int flags = 0;
 545         const char *name = NULL;
 546         struct object_context unused;
 547         struct strbuf buf = STRBUF_INIT;
 548
 549         if (argc > 1 && !strcmp("--parseopt", argv[1]))
 550                 return cmd_parseopt(argc - 1, argv + 1, prefix);
 551
 552         if (argc > 1 && !strcmp("--sq-quote", argv[1]))
 553                 return cmd_sq_quote(argc - 2, argv + 2);
 554
 555         if (argc > 1 && !strcmp("-h", argv[1]))
 556                 usage(builtin_rev_parse_usage);
 557
 558         for (i = 1; i < argc; i++) {
 559                 if (!strcmp(argv[i], "--")) {
 560                         has_dashdash = 1;
 561                         break;
 562                 }
 563         }
 564
 565         /* No options; just report on whether we're in a git repo or not. */
 566         if (argc == 1) {
 567                 setup_git_directory();
 568                 git_config(git_default_config, NULL);
 569                 return 0;
 570         }
 571
 572         for (i = 1; i < argc; i++) {
 573                 const char *arg = argv[i];
 574
 575                 if (!strcmp(arg, "--local-env-vars")) {
 576                         int i;
 577                         for (i = 0; local_repo_env[i]; i++)
 578                                 printf("%s\n", local_repo_env[i]);
 579                         continue;
 580                 }
 581                 if (!strcmp(arg, "--resolve-git-dir")) {
 582                         const char *gitdir = argv[++i];
 583                         if (!gitdir)
 584                                 die("--resolve-git-dir requires an argument");
 585                         gitdir = resolve_gitdir(gitdir);
 586                         if (!gitdir)
 587                                 die("not a gitdir '%s'", argv[i]);
 588                         puts(gitdir);
 589                         continue;
 590                 }
 591
 592                 /* The rest of the options require a git repository. */
 593                 if (!did_repo_setup) {
 594                         prefix = setup_git_directory();
 595                         git_config(git_default_config, NULL);
 596                         did_repo_setup = 1;
 597                 }
 598
 599                 if (!strcmp(arg, "--git-path")) {
 600                         if (!argv[i + 1])
 601                                 die("--git-path requires an argument");
 602                         strbuf_reset(&buf);
 603                         puts(relative_path(git_path("%s", argv[i + 1]),
 604                                            prefix, &buf));
 605                         i++;
 606                         continue;
 607                 }
 608                 if (as_is) {
 609                         if (show_file(arg, output_prefix) && as_is < 2)
 610                                 verify_filename(prefix, arg, 0);
 611                         continue;
 612                 }
 613                 if (!strcmp(arg,"-n")) {
 614                         if (++i >= argc)
 615                                 die("-n requires an argument");
 616                         if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
 617                                 show(arg);
 618                                 show(argv[i]);
 619                         }
 620                         continue;
 621                 }
 622                 if (starts_with(arg, "-n")) {
 623                         if ((filter & DO_FLAGS) && (filter & DO_REVS))
 624                                 show(arg);
 625                         continue;
 626                 }
 627
 628                 if (*arg == '-') {
 629                         if (!strcmp(arg, "--")) {
 630                                 as_is = 2;
 631                                 /* Pass on the "--" if we show anything but files.. */
 632                                 if (filter & (DO_FLAGS | DO_REVS))
 633                                         show_file(arg, 0);
 634                                 continue;
 635                         }
 636                         if (!strcmp(arg, "--default")) {
 637                                 def = argv[++i];
 638                                 if (!def)
 639                                         die("--default requires an argument");
 640                                 continue;
 641                         }
 642                         if (!strcmp(arg, "--prefix")) {
 643                                 prefix = argv[++i];
 644                                 if (!prefix)
 645                                         die("--prefix requires an argument");
 646                                 startup_info->prefix = prefix;
 647                                 output_prefix = 1;
 648                                 continue;
 649                         }
 650                         if (!strcmp(arg, "--revs-only")) {
 651                                 filter &= ~DO_NOREV;
 652                                 continue;
 653                         }
 654                         if (!strcmp(arg, "--no-revs")) {
 655                                 filter &= ~DO_REVS;
 656                                 continue;
 657                         }
 658                         if (!strcmp(arg, "--flags")) {
 659                                 filter &= ~DO_NONFLAGS;
 660                                 continue;
 661                         }
 662                         if (!strcmp(arg, "--no-flags")) {
 663                                 filter &= ~DO_FLAGS;
 664                                 continue;
 665                         }
 666                         if (!strcmp(arg, "--verify")) {
 667                                 filter &= ~(DO_FLAGS|DO_NOREV);
 668                                 verify = 1;
 669                                 continue;
 670                         }
 671                         if (!strcmp(arg, "--quiet") || !strcmp(arg, "-q")) {
 672                                 quiet = 1;
 673                                 flags |= GET_SHA1_QUIETLY;
 674                                 continue;
 675                         }
 676                         if (!strcmp(arg, "--short") ||
 677                             starts_with(arg, "--short=")) {
 678                                 filter &= ~(DO_FLAGS|DO_NOREV);
 679                                 verify = 1;
 680                                 abbrev = DEFAULT_ABBREV;
 681                                 if (!arg[7])
 682                                         continue;
 683                                 abbrev = strtoul(arg + 8, NULL, 10);
 684                                 if (abbrev < MINIMUM_ABBREV)
 685                                         abbrev = MINIMUM_ABBREV;
 686                                 else if (40 <= abbrev)
 687                                         abbrev = 40;
 688                                 continue;
 689                         }
 690                         if (!strcmp(arg, "--sq")) {
 691                                 output_sq = 1;
 692                                 continue;
 693                         }
 694                         if (!strcmp(arg, "--not")) {
 695                                 show_type ^= REVERSED;
 696                                 continue;
 697                         }
 698                         if (!strcmp(arg, "--symbolic")) {
 699                                 symbolic = SHOW_SYMBOLIC_ASIS;
 700                                 continue;
 701                         }
 702                         if (!strcmp(arg, "--symbolic-full-name")) {
 703                                 symbolic = SHOW_SYMBOLIC_FULL;
 704                                 continue;
 705                         }
 706                         if (starts_with(arg, "--abbrev-ref") &&
 707                             (!arg[12] || arg[12] == '=')) {
 708                                 abbrev_ref = 1;
 709                                 abbrev_ref_strict = warn_ambiguous_refs;
 710                                 if (arg[12] == '=') {
 711                                         if (!strcmp(arg + 13, "strict"))
 712                                                 abbrev_ref_strict = 1;
 713                                         else if (!strcmp(arg + 13, "loose"))
 714                                                 abbrev_ref_strict = 0;
 715                                         else
 716                                                 die("unknown mode for %s", arg);
 717                                 }
 718                                 continue;
 719                         }
 720                         if (!strcmp(arg, "--all")) {
 721                                 for_each_ref(show_reference, NULL);
 722                                 continue;
 723                         }
 724                         if (starts_with(arg, "--disambiguate=")) {
 725                                 for_each_abbrev(arg + 15, show_abbrev, NULL);
 726                                 continue;
 727                         }
 728                         if (!strcmp(arg, "--bisect")) {
 729                                 for_each_ref_in("refs/bisect/bad", show_reference, NULL);
 730                                 for_each_ref_in("refs/bisect/good", anti_reference, NULL);
 731                                 continue;
 732                         }
 733                         if (starts_with(arg, "--branches=")) {
 734                                 for_each_glob_ref_in(show_reference, arg + 11,
 735                                         "refs/heads/", NULL);
 736                                 clear_ref_exclusion(&ref_excludes);
 737                                 continue;
 738                         }
 739                         if (!strcmp(arg, "--branches")) {
 740                                 for_each_branch_ref(show_reference, NULL);
 741                                 clear_ref_exclusion(&ref_excludes);
 742                                 continue;
 743                         }
 744                         if (starts_with(arg, "--tags=")) {
 745                                 for_each_glob_ref_in(show_reference, arg + 7,
 746                                         "refs/tags/", NULL);
 747                                 clear_ref_exclusion(&ref_excludes);
 748                                 continue;
 749                         }
 750                         if (!strcmp(arg, "--tags")) {
 751                                 for_each_tag_ref(show_reference, NULL);
 752                                 clear_ref_exclusion(&ref_excludes);
 753                                 continue;
 754                         }
 755                         if (starts_with(arg, "--glob=")) {
 756                                 for_each_glob_ref(show_reference, arg + 7, NULL);
 757                                 clear_ref_exclusion(&ref_excludes);
 758                                 continue;
 759                         }
 760                         if (starts_with(arg, "--remotes=")) {
 761                                 for_each_glob_ref_in(show_reference, arg + 10,
 762                                         "refs/remotes/", NULL);
 763                                 clear_ref_exclusion(&ref_excludes);
 764                                 continue;
 765                         }
 766                         if (!strcmp(arg, "--remotes")) {
 767                                 for_each_remote_ref(show_reference, NULL);
 768                                 clear_ref_exclusion(&ref_excludes);
 769                                 continue;
 770                         }
 771                         if (starts_with(arg, "--exclude=")) {
 772                                 add_ref_exclusion(&ref_excludes, arg + 10);
 773                                 continue;
 774                         }
 775                         if (!strcmp(arg, "--show-toplevel")) {
 776                                 const char *work_tree = get_git_work_tree();
 777                                 if (work_tree)
 778                                         puts(work_tree);
 779                                 continue;
 780                         }
 781                         if (!strcmp(arg, "--show-superproject-working-tree")) {
 782                                 const char *superproject = get_superproject_working_tree();
 783                                 if (superproject)
 784                                         puts(superproject);
 785                                 continue;
 786                         }
 787                         if (!strcmp(arg, "--show-prefix")) {
 788                                 if (prefix)
 789                                         puts(prefix);
 790                                 else
 791                                         putchar('\n');
 792                                 continue;
 793                         }
 794                         if (!strcmp(arg, "--show-cdup")) {
 795                                 const char *pfx = prefix;
 796                                 if (!is_inside_work_tree()) {
 797                                         const char *work_tree =
 798                                                 get_git_work_tree();
 799                                         if (work_tree)
 800                                                 printf("%s\n", work_tree);
 801                                         continue;
 802                                 }
 803                                 while (pfx) {
 804                                         pfx = strchr(pfx, '/');
 805                                         if (pfx) {
 806                                                 pfx++;
 807                                                 printf("../");
 808                                         }
 809                                 }
 810                                 putchar('\n');
 811                                 continue;
 812                         }
 813                         if (!strcmp(arg, "--git-dir") ||
 814                             !strcmp(arg, "--absolute-git-dir")) {
 815                                 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
 816                                 char *cwd;
 817                                 int len;
 818                                 if (arg[2] == 'g') {    /* --git-dir */
 819                                         if (gitdir) {
 820                                                 puts(gitdir);
 821                                                 continue;
 822                                         }
 823                                         if (!prefix) {
 824                                                 puts(".git");
 825                                                 continue;
 826                                         }
 827                                 } else {                /* --absolute-git-dir */
 828                                         if (!gitdir && !prefix)
 829                                                 gitdir = ".git";
 830                                         if (gitdir) {
 831                                                 puts(real_path(gitdir));
 832                                                 continue;
 833                                         }
 834                                 }
 835                                 cwd = xgetcwd();
 836                                 len = strlen(cwd);
 837                                 printf("%s%s.git\n", cwd, len && cwd[len-1] != '/' ? "/" : "");
 838                                 free(cwd);
 839                                 continue;
 840                         }
 841                         if (!strcmp(arg, "--git-common-dir")) {
 842                                 strbuf_reset(&buf);
 843                                 puts(relative_path(get_git_common_dir(),
 844                                                    prefix, &buf));
 845                                 continue;
 846                         }
 847                         if (!strcmp(arg, "--is-inside-git-dir")) {
 848                                 printf("%s\n", is_inside_git_dir() ? "true"
 849                                                 : "false");
 850                                 continue;
 851                         }
 852                         if (!strcmp(arg, "--is-inside-work-tree")) {
 853                                 printf("%s\n", is_inside_work_tree() ? "true"
 854                                                 : "false");
 855                                 continue;
 856                         }
 857                         if (!strcmp(arg, "--is-bare-repository")) {
 858                                 printf("%s\n", is_bare_repository() ? "true"
 859                                                 : "false");
 860                                 continue;
 861                         }
 862                         if (!strcmp(arg, "--shared-index-path")) {
 863                                 if (read_cache() < 0)
 864                                         die(_("Could not read the index"));
 865                                 if (the_index.split_index) {
 866                                         const unsigned char *sha1 = the_index.split_index->base_sha1;
 867                                         const char *path = git_path("sharedindex.%s", sha1_to_hex(sha1));
 868                                         strbuf_reset(&buf);
 869                                         puts(relative_path(path, prefix, &buf));
 870                                 }
 871                                 continue;
 872                         }
 873                         if (starts_with(arg, "--since=")) {
 874                                 show_datestring("--max-age=", arg+8);
 875                                 continue;
 876                         }
 877                         if (starts_with(arg, "--after=")) {
 878                                 show_datestring("--max-age=", arg+8);
 879                                 continue;
 880                         }
 881                         if (starts_with(arg, "--before=")) {
 882                                 show_datestring("--min-age=", arg+9);
 883                                 continue;
 884                         }
 885                         if (starts_with(arg, "--until=")) {
 886                                 show_datestring("--min-age=", arg+8);
 887                                 continue;
 888                         }
 889                         if (show_flag(arg) && verify)
 890                                 die_no_single_rev(quiet);
 891                         continue;
 892                 }
 893
 894                 /* Not a flag argument */
 895                 if (try_difference(arg))
 896                         continue;
 897                 if (try_parent_shorthands(arg))
 898                         continue;
 899                 name = arg;
 900                 type = NORMAL;
 901                 if (*arg == '^') {
 902                         name++;
 903                         type = REVERSED;
 904                 }
 905                 if (!get_sha1_with_context(name, flags, sha1, &unused)) {
 906                         if (verify)
 907                                 revs_count++;
 908                         else
 909                                 show_rev(type, sha1, name);
 910                         continue;
 911                 }
 912                 if (verify)
 913                         die_no_single_rev(quiet);
 914                 if (has_dashdash)
 915                         die("bad revision '%s'", arg);
 916                 as_is = 1;
 917                 if (!show_file(arg, output_prefix))
 918                         continue;
 919                 verify_filename(prefix, arg, 1);
 920         }
 921         strbuf_release(&buf);
 922         if (verify) {
 923                 if (revs_count == 1) {
 924                         show_rev(type, sha1, name);
 925                         return 0;
 926                 } else if (revs_count == 0 && show_default())
 927                         return 0;
 928                 die_no_single_rev(quiet);
 929         } else
 930                 show_default();
 931         return 0;
 932 }