parse-options.c

   1 #include "git-compat-util.h"
   2 #include "parse-options.h"
   3 #include "cache.h"
   4 #include "commit.h"
   5 #include "color.h"
   6 #include "utf8.h"
   7
   8 static int parse_options_usage(struct parse_opt_ctx_t *ctx,
   9                                const char * const *usagestr,
  10                                const struct option *opts, int err);
  11
  12 #define OPT_SHORT 1
  13 #define OPT_UNSET 2
  14
  15 int optbug(const struct option *opt, const char *reason)
  16 {
  17         if (opt->long_name)
  18                 return error("BUG: option '%s' %s", opt->long_name, reason);
  19         return error("BUG: switch '%c' %s", opt->short_name, reason);
  20 }
  21
  22 static int get_arg(struct parse_opt_ctx_t *p, const struct option *opt,
  23                    int flags, const char **arg)
  24 {
  25         if (p->opt) {
  26                 *arg = p->opt;
  27                 p->opt = NULL;
  28         } else if (p->argc == 1 && (opt->flags & PARSE_OPT_LASTARG_DEFAULT)) {
  29                 *arg = (const char *)opt->defval;
  30         } else if (p->argc > 1) {
  31                 p->argc--;
  32                 *arg = *++p->argv;
  33         } else
  34                 return opterror(opt, "requires a value", flags);
  35         return 0;
  36 }
  37
  38 static void fix_filename(const char *prefix, const char **file)
  39 {
  40         if (!file || !*file || !prefix || is_absolute_path(*file)
  41             || !strcmp("-", *file))
  42                 return;
  43         *file = xstrdup(prefix_filename(prefix, strlen(prefix), *file));
  44 }
  45
  46 static int opt_command_mode_error(const struct option *opt,
  47                                   const struct option *all_opts,
  48                                   int flags)
  49 {
  50         const struct option *that;
  51         struct strbuf message = STRBUF_INIT;
  52         struct strbuf that_name = STRBUF_INIT;
  53
  54         /*
  55          * Find the other option that was used to set the variable
  56          * already, and report that this is not compatible with it.
  57          */
  58         for (that = all_opts; that->type != OPTION_END; that++) {
  59                 if (that == opt ||
  60                     that->type != OPTION_CMDMODE ||
  61                     that->value != opt->value ||
  62                     that->defval != *(int *)opt->value)
  63                         continue;
  64
  65                 if (that->long_name)
  66                         strbuf_addf(&that_name, "--%s", that->long_name);
  67                 else
  68                         strbuf_addf(&that_name, "-%c", that->short_name);
  69                 strbuf_addf(&message, ": incompatible with %s", that_name.buf);
  70                 strbuf_release(&that_name);
  71                 opterror(opt, message.buf, flags);
  72                 strbuf_release(&message);
  73                 return -1;
  74         }
  75         return opterror(opt, ": incompatible with something else", flags);
  76 }
  77
  78 static int get_value(struct parse_opt_ctx_t *p,
  79                      const struct option *opt,
  80                      const struct option *all_opts,
  81                      int flags)
  82 {
  83         const char *s, *arg;
  84         const int unset = flags & OPT_UNSET;
  85         int err;
  86
  87         if (unset && p->opt)
  88                 return opterror(opt, "takes no value", flags);
  89         if (unset && (opt->flags & PARSE_OPT_NONEG))
  90                 return opterror(opt, "isn't available", flags);
  91         if (!(flags & OPT_SHORT) && p->opt && (opt->flags & PARSE_OPT_NOARG))
  92                 return opterror(opt, "takes no value", flags);
  93
  94         switch (opt->type) {
  95         case OPTION_LOWLEVEL_CALLBACK:
  96                 return (*(parse_opt_ll_cb *)opt->callback)(p, opt, unset);
  97
  98         case OPTION_BIT:
  99                 if (unset)
 100                         *(int *)opt->value &= ~opt->defval;
 101                 else
 102                         *(int *)opt->value |= opt->defval;
 103                 return 0;
 104
 105         case OPTION_NEGBIT:
 106                 if (unset)
 107                         *(int *)opt->value |= opt->defval;
 108                 else
 109                         *(int *)opt->value &= ~opt->defval;
 110                 return 0;
 111
 112         case OPTION_COUNTUP:
 113                 *(int *)opt->value = unset ? 0 : *(int *)opt->value + 1;
 114                 return 0;
 115
 116         case OPTION_SET_INT:
 117                 *(int *)opt->value = unset ? 0 : opt->defval;
 118                 return 0;
 119
 120         case OPTION_CMDMODE:
 121                 /*
 122                  * Giving the same mode option twice, although is unnecessary,
 123                  * is not a grave error, so let it pass.
 124                  */
 125                 if (*(int *)opt->value && *(int *)opt->value != opt->defval)
 126                         return opt_command_mode_error(opt, all_opts, flags);
 127                 *(int *)opt->value = opt->defval;
 128                 return 0;
 129
 130         case OPTION_SET_PTR:
 131                 *(void **)opt->value = unset ? NULL : (void *)opt->defval;
 132                 return 0;
 133
 134         case OPTION_STRING:
 135                 if (unset)
 136                         *(const char **)opt->value = NULL;
 137                 else if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
 138                         *(const char **)opt->value = (const char *)opt->defval;
 139                 else
 140                         return get_arg(p, opt, flags, (const char **)opt->value);
 141                 return 0;
 142
 143         case OPTION_FILENAME:
 144                 err = 0;
 145                 if (unset)
 146                         *(const char **)opt->value = NULL;
 147                 else if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
 148                         *(const char **)opt->value = (const char *)opt->defval;
 149                 else
 150                         err = get_arg(p, opt, flags, (const char **)opt->value);
 151
 152                 if (!err)
 153                         fix_filename(p->prefix, (const char **)opt->value);
 154                 return err;
 155
 156         case OPTION_CALLBACK:
 157                 if (unset)
 158                         return (*opt->callback)(opt, NULL, 1) ? (-1) : 0;
 159                 if (opt->flags & PARSE_OPT_NOARG)
 160                         return (*opt->callback)(opt, NULL, 0) ? (-1) : 0;
 161                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
 162                         return (*opt->callback)(opt, NULL, 0) ? (-1) : 0;
 163                 if (get_arg(p, opt, flags, &arg))
 164                         return -1;
 165                 return (*opt->callback)(opt, arg, 0) ? (-1) : 0;
 166
 167         case OPTION_INTEGER:
 168                 if (unset) {
 169                         *(int *)opt->value = 0;
 170                         return 0;
 171                 }
 172                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
 173                         *(int *)opt->value = opt->defval;
 174                         return 0;
 175                 }
 176                 if (get_arg(p, opt, flags, &arg))
 177                         return -1;
 178                 *(int *)opt->value = strtol(arg, (char **)&s, 10);
 179                 if (*s)
 180                         return opterror(opt, "expects a numerical value", flags);
 181                 return 0;
 182
 183         default:
 184                 die("should not happen, someone must be hit on the forehead");
 185         }
 186 }
 187
 188 static int parse_short_opt(struct parse_opt_ctx_t *p, const struct option *options)
 189 {
 190         const struct option *all_opts = options;
 191         const struct option *numopt = NULL;
 192
 193         for (; options->type != OPTION_END; options++) {
 194                 if (options->short_name == *p->opt) {
 195                         p->opt = p->opt[1] ? p->opt + 1 : NULL;
 196                         return get_value(p, options, all_opts, OPT_SHORT);
 197                 }
 198
 199                 /*
 200                  * Handle the numerical option later, explicit one-digit
 201                  * options take precedence over it.
 202                  */
 203                 if (options->type == OPTION_NUMBER)
 204                         numopt = options;
 205         }
 206         if (numopt && isdigit(*p->opt)) {
 207                 size_t len = 1;
 208                 char *arg;
 209                 int rc;
 210
 211                 while (isdigit(p->opt[len]))
 212                         len++;
 213                 arg = xmemdupz(p->opt, len);
 214                 p->opt = p->opt[len] ? p->opt + len : NULL;
 215                 rc = (*numopt->callback)(numopt, arg, 0) ? (-1) : 0;
 216                 free(arg);
 217                 return rc;
 218         }
 219         return -2;
 220 }
 221
 222 static int parse_long_opt(struct parse_opt_ctx_t *p, const char *arg,
 223                           const struct option *options)
 224 {
 225         const struct option *all_opts = options;
 226         const char *arg_end = strchrnul(arg, '=');
 227         const struct option *abbrev_option = NULL, *ambiguous_option = NULL;
 228         int abbrev_flags = 0, ambiguous_flags = 0;
 229
 230         for (; options->type != OPTION_END; options++) {
 231                 const char *rest, *long_name = options->long_name;
 232                 int flags = 0, opt_flags = 0;
 233
 234                 if (!long_name)
 235                         continue;
 236
 237 again:
 238                 rest = skip_prefix(arg, long_name);
 239                 if (options->type == OPTION_ARGUMENT) {
 240                         if (!rest)
 241                                 continue;
 242                         if (*rest == '=')
 243                                 return opterror(options, "takes no value", flags);
 244                         if (*rest)
 245                                 continue;
 246                         p->out[p->cpidx++] = arg - 2;
 247                         return 0;
 248                 }
 249                 if (!rest) {
 250                         /* abbreviated? */
 251                         if (!strncmp(long_name, arg, arg_end - arg)) {
 252 is_abbreviated:
 253                                 if (abbrev_option) {
 254                                         /*
 255                                          * If this is abbreviated, it is
 256                                          * ambiguous. So when there is no
 257                                          * exact match later, we need to
 258                                          * error out.
 259                                          */
 260                                         ambiguous_option = abbrev_option;
 261                                         ambiguous_flags = abbrev_flags;
 262                                 }
 263                                 if (!(flags & OPT_UNSET) && *arg_end)
 264                                         p->opt = arg_end + 1;
 265                                 abbrev_option = options;
 266                                 abbrev_flags = flags ^ opt_flags;
 267                                 continue;
 268                         }
 269                         /* negation allowed? */
 270                         if (options->flags & PARSE_OPT_NONEG)
 271                                 continue;
 272                         /* negated and abbreviated very much? */
 273                         if (starts_with("no-", arg)) {
 274                                 flags |= OPT_UNSET;
 275                                 goto is_abbreviated;
 276                         }
 277                         /* negated? */
 278                         if (!starts_with(arg, "no-")) {
 279                                 if (starts_with(long_name, "no-")) {
 280                                         long_name += 3;
 281                                         opt_flags |= OPT_UNSET;
 282                                         goto again;
 283                                 }
 284                                 continue;
 285                         }
 286                         flags |= OPT_UNSET;
 287                         rest = skip_prefix(arg + 3, long_name);
 288                         /* abbreviated and negated? */
 289                         if (!rest && starts_with(long_name, arg + 3))
 290                                 goto is_abbreviated;
 291                         if (!rest)
 292                                 continue;
 293                 }
 294                 if (*rest) {
 295                         if (*rest != '=')
 296                                 continue;
 297                         p->opt = rest + 1;
 298                 }
 299                 return get_value(p, options, all_opts, flags ^ opt_flags);
 300         }
 301
 302         if (ambiguous_option)
 303                 return error("Ambiguous option: %s "
 304                         "(could be --%s%s or --%s%s)",
 305                         arg,
 306                         (ambiguous_flags & OPT_UNSET) ?  "no-" : "",
 307                         ambiguous_option->long_name,
 308                         (abbrev_flags & OPT_UNSET) ?  "no-" : "",
 309                         abbrev_option->long_name);
 310         if (abbrev_option)
 311                 return get_value(p, abbrev_option, all_opts, abbrev_flags);
 312         return -2;
 313 }
 314
 315 static int parse_nodash_opt(struct parse_opt_ctx_t *p, const char *arg,
 316                             const struct option *options)
 317 {
 318         const struct option *all_opts = options;
 319
 320         for (; options->type != OPTION_END; options++) {
 321                 if (!(options->flags & PARSE_OPT_NODASH))
 322                         continue;
 323                 if (options->short_name == arg[0] && arg[1] == '\0')
 324                         return get_value(p, options, all_opts, OPT_SHORT);
 325         }
 326         return -2;
 327 }
 328
 329 static void check_typos(const char *arg, const struct option *options)
 330 {
 331         if (strlen(arg) < 3)
 332                 return;
 333
 334         if (starts_with(arg, "no-")) {
 335                 error ("did you mean `--%s` (with two dashes ?)", arg);
 336                 exit(129);
 337         }
 338
 339         for (; options->type != OPTION_END; options++) {
 340                 if (!options->long_name)
 341                         continue;
 342                 if (starts_with(options->long_name, arg)) {
 343                         error ("did you mean `--%s` (with two dashes ?)", arg);
 344                         exit(129);
 345                 }
 346         }
 347 }
 348
 349 static void parse_options_check(const struct option *opts)
 350 {
 351         int err = 0;
 352
 353         for (; opts->type != OPTION_END; opts++) {
 354                 if ((opts->flags & PARSE_OPT_LASTARG_DEFAULT) &&
 355                     (opts->flags & PARSE_OPT_OPTARG))
 356                         err |= optbug(opts, "uses incompatible flags "
 357                                         "LASTARG_DEFAULT and OPTARG");
 358                 if (opts->flags & PARSE_OPT_NODASH &&
 359                     ((opts->flags & PARSE_OPT_OPTARG) ||
 360                      !(opts->flags & PARSE_OPT_NOARG) ||
 361                      !(opts->flags & PARSE_OPT_NONEG) ||
 362                      opts->long_name))
 363                         err |= optbug(opts, "uses feature "
 364                                         "not supported for dashless options");
 365                 switch (opts->type) {
 366                 case OPTION_COUNTUP:
 367                 case OPTION_BIT:
 368                 case OPTION_NEGBIT:
 369                 case OPTION_SET_INT:
 370                 case OPTION_SET_PTR:
 371                 case OPTION_NUMBER:
 372                         if ((opts->flags & PARSE_OPT_OPTARG) ||
 373                             !(opts->flags & PARSE_OPT_NOARG))
 374                                 err |= optbug(opts, "should not accept an argument");
 375                 default:
 376                         ; /* ok. (usually accepts an argument) */
 377                 }
 378         }
 379         if (err)
 380                 exit(128);
 381 }
 382
 383 void parse_options_start(struct parse_opt_ctx_t *ctx,
 384                          int argc, const char **argv, const char *prefix,
 385                          const struct option *options, int flags)
 386 {
 387         memset(ctx, 0, sizeof(*ctx));
 388         ctx->argc = argc - 1;
 389         ctx->argv = argv + 1;
 390         ctx->out  = argv;
 391         ctx->prefix = prefix;
 392         ctx->cpidx = ((flags & PARSE_OPT_KEEP_ARGV0) != 0);
 393         ctx->flags = flags;
 394         if ((flags & PARSE_OPT_KEEP_UNKNOWN) &&
 395             (flags & PARSE_OPT_STOP_AT_NON_OPTION))
 396                 die("STOP_AT_NON_OPTION and KEEP_UNKNOWN don't go together");
 397         parse_options_check(options);
 398 }
 399
 400 static int usage_with_options_internal(struct parse_opt_ctx_t *,
 401                                        const char * const *,
 402                                        const struct option *, int, int);
 403
 404 int parse_options_step(struct parse_opt_ctx_t *ctx,
 405                        const struct option *options,
 406                        const char * const usagestr[])
 407 {
 408         int internal_help = !(ctx->flags & PARSE_OPT_NO_INTERNAL_HELP);
 409
 410         /* we must reset ->opt, unknown short option leave it dangling */
 411         ctx->opt = NULL;
 412
 413         for (; ctx->argc; ctx->argc--, ctx->argv++) {
 414                 const char *arg = ctx->argv[0];
 415
 416                 if (*arg != '-' || !arg[1]) {
 417                         if (parse_nodash_opt(ctx, arg, options) == 0)
 418                                 continue;
 419                         if (ctx->flags & PARSE_OPT_STOP_AT_NON_OPTION)
 420                                 return PARSE_OPT_NON_OPTION;
 421                         ctx->out[ctx->cpidx++] = ctx->argv[0];
 422                         continue;
 423                 }
 424
 425                 if (arg[1] != '-') {
 426                         ctx->opt = arg + 1;
 427                         if (internal_help && *ctx->opt == 'h')
 428                                 return parse_options_usage(ctx, usagestr, options, 0);
 429                         switch (parse_short_opt(ctx, options)) {
 430                         case -1:
 431                                 return parse_options_usage(ctx, usagestr, options, 1);
 432                         case -2:
 433                                 if (ctx->opt)
 434                                         check_typos(arg + 1, options);
 435                                 goto unknown;
 436                         }
 437                         if (ctx->opt)
 438                                 check_typos(arg + 1, options);
 439                         while (ctx->opt) {
 440                                 if (internal_help && *ctx->opt == 'h')
 441                                         return parse_options_usage(ctx, usagestr, options, 0);
 442                                 switch (parse_short_opt(ctx, options)) {
 443                                 case -1:
 444                                         return parse_options_usage(ctx, usagestr, options, 1);
 445                                 case -2:
 446                                         /* fake a short option thing to hide the fact that we may have
 447                                          * started to parse aggregated stuff
 448                                          *
 449                                          * This is leaky, too bad.
 450                                          */
 451                                         ctx->argv[0] = xstrdup(ctx->opt - 1);
 452                                         *(char *)ctx->argv[0] = '-';
 453                                         goto unknown;
 454                                 }
 455                         }
 456                         continue;
 457                 }
 458
 459                 if (!arg[2]) { /* "--" */
 460                         if (!(ctx->flags & PARSE_OPT_KEEP_DASHDASH)) {
 461                                 ctx->argc--;
 462                                 ctx->argv++;
 463                         }
 464                         break;
 465                 }
 466
 467                 if (internal_help && !strcmp(arg + 2, "help-all"))
 468                         return usage_with_options_internal(ctx, usagestr, options, 1, 0);
 469                 if (internal_help && !strcmp(arg + 2, "help"))
 470                         return parse_options_usage(ctx, usagestr, options, 0);
 471                 switch (parse_long_opt(ctx, arg + 2, options)) {
 472                 case -1:
 473                         return parse_options_usage(ctx, usagestr, options, 1);
 474                 case -2:
 475                         goto unknown;
 476                 }
 477                 continue;
 478 unknown:
 479                 if (!(ctx->flags & PARSE_OPT_KEEP_UNKNOWN))
 480                         return PARSE_OPT_UNKNOWN;
 481                 ctx->out[ctx->cpidx++] = ctx->argv[0];
 482                 ctx->opt = NULL;
 483         }
 484         return PARSE_OPT_DONE;
 485 }
 486
 487 int parse_options_end(struct parse_opt_ctx_t *ctx)
 488 {
 489         memmove(ctx->out + ctx->cpidx, ctx->argv, ctx->argc * sizeof(*ctx->out));
 490         ctx->out[ctx->cpidx + ctx->argc] = NULL;
 491         return ctx->cpidx + ctx->argc;
 492 }
 493
 494 int parse_options(int argc, const char **argv, const char *prefix,
 495                   const struct option *options, const char * const usagestr[],
 496                   int flags)
 497 {
 498         struct parse_opt_ctx_t ctx;
 499
 500         parse_options_start(&ctx, argc, argv, prefix, options, flags);
 501         switch (parse_options_step(&ctx, options, usagestr)) {
 502         case PARSE_OPT_HELP:
 503                 exit(129);
 504         case PARSE_OPT_NON_OPTION:
 505         case PARSE_OPT_DONE:
 506                 break;
 507         default: /* PARSE_OPT_UNKNOWN */
 508                 if (ctx.argv[0][1] == '-') {
 509                         error("unknown option `%s'", ctx.argv[0] + 2);
 510                 } else if (isascii(*ctx.opt)) {
 511                         error("unknown switch `%c'", *ctx.opt);
 512                 } else {
 513                         error("unknown non-ascii option in string: `%s'",
 514                               ctx.argv[0]);
 515                 }
 516                 usage_with_options(usagestr, options);
 517         }
 518
 519         precompose_argv(argc, argv);
 520         return parse_options_end(&ctx);
 521 }
 522
 523 static int usage_argh(const struct option *opts, FILE *outfile)
 524 {
 525         const char *s;
 526         int literal = (opts->flags & PARSE_OPT_LITERAL_ARGHELP) || !opts->argh;
 527         if (opts->flags & PARSE_OPT_OPTARG)
 528                 if (opts->long_name)
 529                         s = literal ? "[=%s]" : "[=<%s>]";
 530                 else
 531                         s = literal ? "[%s]" : "[<%s>]";
 532         else
 533                 s = literal ? " %s" : " <%s>";
 534         return utf8_fprintf(outfile, s, opts->argh ? _(opts->argh) : _("..."));
 535 }
 536
 537 #define USAGE_OPTS_WIDTH 24
 538 #define USAGE_GAP         2
 539
 540 static int usage_with_options_internal(struct parse_opt_ctx_t *ctx,
 541                                        const char * const *usagestr,
 542                                        const struct option *opts, int full, int err)
 543 {
 544         FILE *outfile = err ? stderr : stdout;
 545
 546         if (!usagestr)
 547                 return PARSE_OPT_HELP;
 548
 549         if (!err && ctx && ctx->flags & PARSE_OPT_SHELL_EVAL)
 550                 fprintf(outfile, "cat <<\\EOF\n");
 551
 552         fprintf_ln(outfile, _("usage: %s"), _(*usagestr++));
 553         while (*usagestr && **usagestr)
 554                 /* TRANSLATORS: the colon here should align with the
 555                    one in "usage: %s" translation */
 556                 fprintf_ln(outfile, _("   or: %s"), _(*usagestr++));
 557         while (*usagestr) {
 558                 if (**usagestr)
 559                         fprintf_ln(outfile, _("    %s"), _(*usagestr));
 560                 else
 561                         putchar('\n');
 562                 usagestr++;
 563         }
 564
 565         if (opts->type != OPTION_GROUP)
 566                 fputc('\n', outfile);
 567
 568         for (; opts->type != OPTION_END; opts++) {
 569                 size_t pos;
 570                 int pad;
 571
 572                 if (opts->type == OPTION_GROUP) {
 573                         fputc('\n', outfile);
 574                         if (*opts->help)
 575                                 fprintf(outfile, "%s\n", _(opts->help));
 576                         continue;
 577                 }
 578                 if (!full && (opts->flags & PARSE_OPT_HIDDEN))
 579                         continue;
 580
 581                 pos = fprintf(outfile, "    ");
 582                 if (opts->short_name) {
 583                         if (opts->flags & PARSE_OPT_NODASH)
 584                                 pos += fprintf(outfile, "%c", opts->short_name);
 585                         else
 586                                 pos += fprintf(outfile, "-%c", opts->short_name);
 587                 }
 588                 if (opts->long_name && opts->short_name)
 589                         pos += fprintf(outfile, ", ");
 590                 if (opts->long_name)
 591                         pos += fprintf(outfile, "--%s", opts->long_name);
 592                 if (opts->type == OPTION_NUMBER)
 593                         pos += utf8_fprintf(outfile, _("-NUM"));
 594
 595                 if ((opts->flags & PARSE_OPT_LITERAL_ARGHELP) ||
 596                     !(opts->flags & PARSE_OPT_NOARG))
 597                         pos += usage_argh(opts, outfile);
 598
 599                 if (pos <= USAGE_OPTS_WIDTH)
 600                         pad = USAGE_OPTS_WIDTH - pos;
 601                 else {
 602                         fputc('\n', outfile);
 603                         pad = USAGE_OPTS_WIDTH;
 604                 }
 605                 fprintf(outfile, "%*s%s\n", pad + USAGE_GAP, "", _(opts->help));
 606         }
 607         fputc('\n', outfile);
 608
 609         if (!err && ctx && ctx->flags & PARSE_OPT_SHELL_EVAL)
 610                 fputs("EOF\n", outfile);
 611
 612         return PARSE_OPT_HELP;
 613 }
 614
 615 void NORETURN usage_with_options(const char * const *usagestr,
 616                         const struct option *opts)
 617 {
 618         usage_with_options_internal(NULL, usagestr, opts, 0, 1);
 619         exit(129);
 620 }
 621
 622 void NORETURN usage_msg_opt(const char *msg,
 623                    const char * const *usagestr,
 624                    const struct option *options)
 625 {
 626         fprintf(stderr, "%s\n\n", msg);
 627         usage_with_options(usagestr, options);
 628 }
 629
 630 static int parse_options_usage(struct parse_opt_ctx_t *ctx,
 631                                const char * const *usagestr,
 632                                const struct option *opts, int err)
 633 {
 634         return usage_with_options_internal(ctx, usagestr, opts, 0, err);
 635 }
 636
 637 #undef opterror
 638 int opterror(const struct option *opt, const char *reason, int flags)
 639 {
 640         if (flags & OPT_SHORT)
 641                 return error("switch `%c' %s", opt->short_name, reason);
 642         if (flags & OPT_UNSET)
 643                 return error("option `no-%s' %s", opt->long_name, reason);
 644         return error("option `%s' %s", opt->long_name, reason);
 645 }