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