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
  19 static int filter = ~0;
  20
  21 static const char *def;
  22
  23 #define NORMAL 0
  24 #define REVERSED 1
  25 static int show_type = NORMAL;
  26
  27 #define SHOW_SYMBOLIC_ASIS 1
  28 #define SHOW_SYMBOLIC_FULL 2
  29 static int symbolic;
  30 static int abbrev;
  31 static int abbrev_ref;
  32 static int abbrev_ref_strict;
  33 static int output_sq;
  34
  35 static int stuck_long;
  36 static 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  */
  43 static 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 */
  95 static 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 */
 114 static 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 */
 122 static 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. */
 164 static 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
 175 static 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
 191 static 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
 199 static 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
 205 static int show_abbrev(const unsigned char *sha1, void *cb_data)
 206 {
 207         show_rev(NORMAL, sha1, NULL);
 208         return 0;
 209 }
 210
 211 static 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
 222 static 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
 238 static 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
 296 static 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
 329 static 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
 348 static const char *skipspaces(const char *s)
 349 {
 350         while (isspace(*s))
 351                 s++;
 352         return s;
 353 }
 354
 355 static 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
 465 static 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
 477 static void die_no_single_rev(int quiet)
 478 {
 479         if (quiet)
 480                 exit(1);
 481         else
 482                 die("Needed a single revision");
 483 }
 484
 485 static const char builtin_rev_parse_usage[] =
 486 N_("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
 492 int 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 }