Andrew's git / gitweb.git / parse-options.c
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parse-options.con commit imap-send: use parse options API to determine verbosity (f1a3529)
   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
   8static 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
  15int optbug(const struct option *opt, const char *reason)
  16{
  17        if (opt->long_name) {
  18                if (opt->short_name)
  19                        return error("BUG: switch '%c' (--%s) %s",
  20                                     opt->short_name, opt->long_name, reason);
  21                return error("BUG: option '%s' %s", opt->long_name, reason);
  22        }
  23        return error("BUG: switch '%c' %s", opt->short_name, reason);
  24}
  25
  26static int get_arg(struct parse_opt_ctx_t *p, const struct option *opt,
  27                   int flags, const char **arg)
  28{
  29        if (p->opt) {
  30                *arg = p->opt;
  31                p->opt = NULL;
  32        } else if (p->argc == 1 && (opt->flags & PARSE_OPT_LASTARG_DEFAULT)) {
  33                *arg = (const char *)opt->defval;
  34        } else if (p->argc > 1) {
  35                p->argc--;
  36                *arg = *++p->argv;
  37        } else
  38                return opterror(opt, "requires a value", flags);
  39        return 0;
  40}
  41
  42static void fix_filename(const char *prefix, const char **file)
  43{
  44        if (!file || !*file || !prefix || is_absolute_path(*file)
  45            || !strcmp("-", *file))
  46                return;
  47        *file = xstrdup(prefix_filename(prefix, strlen(prefix), *file));
  48}
  49
  50static int opt_command_mode_error(const struct option *opt,
  51                                  const struct option *all_opts,
  52                                  int flags)
  53{
  54        const struct option *that;
  55        struct strbuf message = STRBUF_INIT;
  56        struct strbuf that_name = STRBUF_INIT;
  57
  58        /*
  59         * Find the other option that was used to set the variable
  60         * already, and report that this is not compatible with it.
  61         */
  62        for (that = all_opts; that->type != OPTION_END; that++) {
  63                if (that == opt ||
  64                    that->type != OPTION_CMDMODE ||
  65                    that->value != opt->value ||
  66                    that->defval != *(int *)opt->value)
  67                        continue;
  68
  69                if (that->long_name)
  70                        strbuf_addf(&that_name, "--%s", that->long_name);
  71                else
  72                        strbuf_addf(&that_name, "-%c", that->short_name);
  73                strbuf_addf(&message, ": incompatible with %s", that_name.buf);
  74                strbuf_release(&that_name);
  75                opterror(opt, message.buf, flags);
  76                strbuf_release(&message);
  77                return -1;
  78        }
  79        return opterror(opt, ": incompatible with something else", flags);
  80}
  81
  82static int get_value(struct parse_opt_ctx_t *p,
  83                     const struct option *opt,
  84                     const struct option *all_opts,
  85                     int flags)
  86{
  87        const char *s, *arg;
  88        const int unset = flags & OPT_UNSET;
  89        int err;
  90
  91        if (unset && p->opt)
  92                return opterror(opt, "takes no value", flags);
  93        if (unset && (opt->flags & PARSE_OPT_NONEG))
  94                return opterror(opt, "isn't available", flags);
  95        if (!(flags & OPT_SHORT) && p->opt && (opt->flags & PARSE_OPT_NOARG))
  96                return opterror(opt, "takes no value", flags);
  97
  98        switch (opt->type) {
  99        case OPTION_LOWLEVEL_CALLBACK:
 100                return (*(parse_opt_ll_cb *)opt->callback)(p, opt, unset);
 101
 102        case OPTION_BIT:
 103                if (unset)
 104                        *(int *)opt->value &= ~opt->defval;
 105                else
 106                        *(int *)opt->value |= opt->defval;
 107                return 0;
 108
 109        case OPTION_NEGBIT:
 110                if (unset)
 111                        *(int *)opt->value |= opt->defval;
 112                else
 113                        *(int *)opt->value &= ~opt->defval;
 114                return 0;
 115
 116        case OPTION_COUNTUP:
 117                *(int *)opt->value = unset ? 0 : *(int *)opt->value + 1;
 118                return 0;
 119
 120        case OPTION_SET_INT:
 121                *(int *)opt->value = unset ? 0 : opt->defval;
 122                return 0;
 123
 124        case OPTION_CMDMODE:
 125                /*
 126                 * Giving the same mode option twice, although is unnecessary,
 127                 * is not a grave error, so let it pass.
 128                 */
 129                if (*(int *)opt->value && *(int *)opt->value != opt->defval)
 130                        return opt_command_mode_error(opt, all_opts, flags);
 131                *(int *)opt->value = 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
 188static 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
 222static 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
 237again:
 238                if (!skip_prefix(arg, long_name, &rest))
 239                        rest = NULL;
 240                if (options->type == OPTION_ARGUMENT) {
 241                        if (!rest)
 242                                continue;
 243                        if (*rest == '=')
 244                                return opterror(options, "takes no value", flags);
 245                        if (*rest)
 246                                continue;
 247                        p->out[p->cpidx++] = arg - 2;
 248                        return 0;
 249                }
 250                if (!rest) {
 251                        /* abbreviated? */
 252                        if (!strncmp(long_name, arg, arg_end - arg)) {
 253is_abbreviated:
 254                                if (abbrev_option) {
 255                                        /*
 256                                         * If this is abbreviated, it is
 257                                         * ambiguous. So when there is no
 258                                         * exact match later, we need to
 259                                         * error out.
 260                                         */
 261                                        ambiguous_option = abbrev_option;
 262                                        ambiguous_flags = abbrev_flags;
 263                                }
 264                                if (!(flags & OPT_UNSET) && *arg_end)
 265                                        p->opt = arg_end + 1;
 266                                abbrev_option = options;
 267                                abbrev_flags = flags ^ opt_flags;
 268                                continue;
 269                        }
 270                        /* negation allowed? */
 271                        if (options->flags & PARSE_OPT_NONEG)
 272                                continue;
 273                        /* negated and abbreviated very much? */
 274                        if (starts_with("no-", arg)) {
 275                                flags |= OPT_UNSET;
 276                                goto is_abbreviated;
 277                        }
 278                        /* negated? */
 279                        if (!starts_with(arg, "no-")) {
 280                                if (starts_with(long_name, "no-")) {
 281                                        long_name += 3;
 282                                        opt_flags |= OPT_UNSET;
 283                                        goto again;
 284                                }
 285                                continue;
 286                        }
 287                        flags |= OPT_UNSET;
 288                        if (!skip_prefix(arg + 3, long_name, &rest)) {
 289                                /* abbreviated and negated? */
 290                                if (starts_with(long_name, arg + 3))
 291                                        goto is_abbreviated;
 292                                else
 293                                        continue;
 294                        }
 295                }
 296                if (*rest) {
 297                        if (*rest != '=')
 298                                continue;
 299                        p->opt = rest + 1;
 300                }
 301                return get_value(p, options, all_opts, flags ^ opt_flags);
 302        }
 303
 304        if (ambiguous_option)
 305                return error("Ambiguous option: %s "
 306                        "(could be --%s%s or --%s%s)",
 307                        arg,
 308                        (ambiguous_flags & OPT_UNSET) ?  "no-" : "",
 309                        ambiguous_option->long_name,
 310                        (abbrev_flags & OPT_UNSET) ?  "no-" : "",
 311                        abbrev_option->long_name);
 312        if (abbrev_option)
 313                return get_value(p, abbrev_option, all_opts, abbrev_flags);
 314        return -2;
 315}
 316
 317static int parse_nodash_opt(struct parse_opt_ctx_t *p, const char *arg,
 318                            const struct option *options)
 319{
 320        const struct option *all_opts = options;
 321
 322        for (; options->type != OPTION_END; options++) {
 323                if (!(options->flags & PARSE_OPT_NODASH))
 324                        continue;
 325                if (options->short_name == arg[0] && arg[1] == '\0')
 326                        return get_value(p, options, all_opts, OPT_SHORT);
 327        }
 328        return -2;
 329}
 330
 331static void check_typos(const char *arg, const struct option *options)
 332{
 333        if (strlen(arg) < 3)
 334                return;
 335
 336        if (starts_with(arg, "no-")) {
 337                error ("did you mean `--%s` (with two dashes ?)", arg);
 338                exit(129);
 339        }
 340
 341        for (; options->type != OPTION_END; options++) {
 342                if (!options->long_name)
 343                        continue;
 344                if (starts_with(options->long_name, arg)) {
 345                        error ("did you mean `--%s` (with two dashes ?)", arg);
 346                        exit(129);
 347                }
 348        }
 349}
 350
 351static void parse_options_check(const struct option *opts)
 352{
 353        int err = 0;
 354        char short_opts[128];
 355
 356        memset(short_opts, '\0', sizeof(short_opts));
 357        for (; opts->type != OPTION_END; opts++) {
 358                if ((opts->flags & PARSE_OPT_LASTARG_DEFAULT) &&
 359                    (opts->flags & PARSE_OPT_OPTARG))
 360                        err |= optbug(opts, "uses incompatible flags "
 361                                        "LASTARG_DEFAULT and OPTARG");
 362                if (opts->short_name) {
 363                        if (0x7F <= opts->short_name)
 364                                err |= optbug(opts, "invalid short name");
 365                        else if (short_opts[opts->short_name]++)
 366                                err |= optbug(opts, "short name already used");
 367                }
 368                if (opts->flags & PARSE_OPT_NODASH &&
 369                    ((opts->flags & PARSE_OPT_OPTARG) ||
 370                     !(opts->flags & PARSE_OPT_NOARG) ||
 371                     !(opts->flags & PARSE_OPT_NONEG) ||
 372                     opts->long_name))
 373                        err |= optbug(opts, "uses feature "
 374                                        "not supported for dashless options");
 375                switch (opts->type) {
 376                case OPTION_COUNTUP:
 377                case OPTION_BIT:
 378                case OPTION_NEGBIT:
 379                case OPTION_SET_INT:
 380                case OPTION_NUMBER:
 381                        if ((opts->flags & PARSE_OPT_OPTARG) ||
 382                            !(opts->flags & PARSE_OPT_NOARG))
 383                                err |= optbug(opts, "should not accept an argument");
 384                default:
 385                        ; /* ok. (usually accepts an argument) */
 386                }
 387                if (opts->argh &&
 388                    strcspn(opts->argh, " _") != strlen(opts->argh))
 389                        err |= optbug(opts, "multi-word argh should use dash to separate words");
 390        }
 391        if (err)
 392                exit(128);
 393}
 394
 395void parse_options_start(struct parse_opt_ctx_t *ctx,
 396                         int argc, const char **argv, const char *prefix,
 397                         const struct option *options, int flags)
 398{
 399        memset(ctx, 0, sizeof(*ctx));
 400        ctx->argc = argc - 1;
 401        ctx->argv = argv + 1;
 402        ctx->out  = argv;
 403        ctx->prefix = prefix;
 404        ctx->cpidx = ((flags & PARSE_OPT_KEEP_ARGV0) != 0);
 405        ctx->flags = flags;
 406        if ((flags & PARSE_OPT_KEEP_UNKNOWN) &&
 407            (flags & PARSE_OPT_STOP_AT_NON_OPTION))
 408                die("STOP_AT_NON_OPTION and KEEP_UNKNOWN don't go together");
 409        parse_options_check(options);
 410}
 411
 412static int usage_with_options_internal(struct parse_opt_ctx_t *,
 413                                       const char * const *,
 414                                       const struct option *, int, int);
 415
 416int parse_options_step(struct parse_opt_ctx_t *ctx,
 417                       const struct option *options,
 418                       const char * const usagestr[])
 419{
 420        int internal_help = !(ctx->flags & PARSE_OPT_NO_INTERNAL_HELP);
 421
 422        /* we must reset ->opt, unknown short option leave it dangling */
 423        ctx->opt = NULL;
 424
 425        for (; ctx->argc; ctx->argc--, ctx->argv++) {
 426                const char *arg = ctx->argv[0];
 427
 428                if (*arg != '-' || !arg[1]) {
 429                        if (parse_nodash_opt(ctx, arg, options) == 0)
 430                                continue;
 431                        if (ctx->flags & PARSE_OPT_STOP_AT_NON_OPTION)
 432                                return PARSE_OPT_NON_OPTION;
 433                        ctx->out[ctx->cpidx++] = ctx->argv[0];
 434                        continue;
 435                }
 436
 437                if (arg[1] != '-') {
 438                        ctx->opt = arg + 1;
 439                        if (internal_help && *ctx->opt == 'h')
 440                                return parse_options_usage(ctx, usagestr, options, 0);
 441                        switch (parse_short_opt(ctx, options)) {
 442                        case -1:
 443                                return parse_options_usage(ctx, usagestr, options, 1);
 444                        case -2:
 445                                if (ctx->opt)
 446                                        check_typos(arg + 1, options);
 447                                goto unknown;
 448                        }
 449                        if (ctx->opt)
 450                                check_typos(arg + 1, options);
 451                        while (ctx->opt) {
 452                                if (internal_help && *ctx->opt == 'h')
 453                                        return parse_options_usage(ctx, usagestr, options, 0);
 454                                switch (parse_short_opt(ctx, options)) {
 455                                case -1:
 456                                        return parse_options_usage(ctx, usagestr, options, 1);
 457                                case -2:
 458                                        /* fake a short option thing to hide the fact that we may have
 459                                         * started to parse aggregated stuff
 460                                         *
 461                                         * This is leaky, too bad.
 462                                         */
 463                                        ctx->argv[0] = xstrdup(ctx->opt - 1);
 464                                        *(char *)ctx->argv[0] = '-';
 465                                        goto unknown;
 466                                }
 467                        }
 468                        continue;
 469                }
 470
 471                if (!arg[2]) { /* "--" */
 472                        if (!(ctx->flags & PARSE_OPT_KEEP_DASHDASH)) {
 473                                ctx->argc--;
 474                                ctx->argv++;
 475                        }
 476                        break;
 477                }
 478
 479                if (internal_help && !strcmp(arg + 2, "help-all"))
 480                        return usage_with_options_internal(ctx, usagestr, options, 1, 0);
 481                if (internal_help && !strcmp(arg + 2, "help"))
 482                        return parse_options_usage(ctx, usagestr, options, 0);
 483                switch (parse_long_opt(ctx, arg + 2, options)) {
 484                case -1:
 485                        return parse_options_usage(ctx, usagestr, options, 1);
 486                case -2:
 487                        goto unknown;
 488                }
 489                continue;
 490unknown:
 491                if (!(ctx->flags & PARSE_OPT_KEEP_UNKNOWN))
 492                        return PARSE_OPT_UNKNOWN;
 493                ctx->out[ctx->cpidx++] = ctx->argv[0];
 494                ctx->opt = NULL;
 495        }
 496        return PARSE_OPT_DONE;
 497}
 498
 499int parse_options_end(struct parse_opt_ctx_t *ctx)
 500{
 501        memmove(ctx->out + ctx->cpidx, ctx->argv, ctx->argc * sizeof(*ctx->out));
 502        ctx->out[ctx->cpidx + ctx->argc] = NULL;
 503        return ctx->cpidx + ctx->argc;
 504}
 505
 506int parse_options(int argc, const char **argv, const char *prefix,
 507                  const struct option *options, const char * const usagestr[],
 508                  int flags)
 509{
 510        struct parse_opt_ctx_t ctx;
 511
 512        parse_options_start(&ctx, argc, argv, prefix, options, flags);
 513        switch (parse_options_step(&ctx, options, usagestr)) {
 514        case PARSE_OPT_HELP:
 515                exit(129);
 516        case PARSE_OPT_NON_OPTION:
 517        case PARSE_OPT_DONE:
 518                break;
 519        default: /* PARSE_OPT_UNKNOWN */
 520                if (ctx.argv[0][1] == '-') {
 521                        error("unknown option `%s'", ctx.argv[0] + 2);
 522                } else if (isascii(*ctx.opt)) {
 523                        error("unknown switch `%c'", *ctx.opt);
 524                } else {
 525                        error("unknown non-ascii option in string: `%s'",
 526                              ctx.argv[0]);
 527                }
 528                usage_with_options(usagestr, options);
 529        }
 530
 531        precompose_argv(argc, argv);
 532        return parse_options_end(&ctx);
 533}
 534
 535static int usage_argh(const struct option *opts, FILE *outfile)
 536{
 537        const char *s;
 538        int literal = (opts->flags & PARSE_OPT_LITERAL_ARGHELP) || !opts->argh;
 539        if (opts->flags & PARSE_OPT_OPTARG)
 540                if (opts->long_name)
 541                        s = literal ? "[=%s]" : "[=<%s>]";
 542                else
 543                        s = literal ? "[%s]" : "[<%s>]";
 544        else
 545                s = literal ? " %s" : " <%s>";
 546        return utf8_fprintf(outfile, s, opts->argh ? _(opts->argh) : _("..."));
 547}
 548
 549#define USAGE_OPTS_WIDTH 24
 550#define USAGE_GAP         2
 551
 552static int usage_with_options_internal(struct parse_opt_ctx_t *ctx,
 553                                       const char * const *usagestr,
 554                                       const struct option *opts, int full, int err)
 555{
 556        FILE *outfile = err ? stderr : stdout;
 557
 558        if (!usagestr)
 559                return PARSE_OPT_HELP;
 560
 561        if (!err && ctx && ctx->flags & PARSE_OPT_SHELL_EVAL)
 562                fprintf(outfile, "cat <<\\EOF\n");
 563
 564        fprintf_ln(outfile, _("usage: %s"), _(*usagestr++));
 565        while (*usagestr && **usagestr)
 566                /* TRANSLATORS: the colon here should align with the
 567                   one in "usage: %s" translation */
 568                fprintf_ln(outfile, _("   or: %s"), _(*usagestr++));
 569        while (*usagestr) {
 570                if (**usagestr)
 571                        fprintf_ln(outfile, _("    %s"), _(*usagestr));
 572                else
 573                        putchar('\n');
 574                usagestr++;
 575        }
 576
 577        if (opts->type != OPTION_GROUP)
 578                fputc('\n', outfile);
 579
 580        for (; opts->type != OPTION_END; opts++) {
 581                size_t pos;
 582                int pad;
 583
 584                if (opts->type == OPTION_GROUP) {
 585                        fputc('\n', outfile);
 586                        if (*opts->help)
 587                                fprintf(outfile, "%s\n", _(opts->help));
 588                        continue;
 589                }
 590                if (!full && (opts->flags & PARSE_OPT_HIDDEN))
 591                        continue;
 592
 593                pos = fprintf(outfile, "    ");
 594                if (opts->short_name) {
 595                        if (opts->flags & PARSE_OPT_NODASH)
 596                                pos += fprintf(outfile, "%c", opts->short_name);
 597                        else
 598                                pos += fprintf(outfile, "-%c", opts->short_name);
 599                }
 600                if (opts->long_name && opts->short_name)
 601                        pos += fprintf(outfile, ", ");
 602                if (opts->long_name)
 603                        pos += fprintf(outfile, "--%s", opts->long_name);
 604                if (opts->type == OPTION_NUMBER)
 605                        pos += utf8_fprintf(outfile, _("-NUM"));
 606
 607                if ((opts->flags & PARSE_OPT_LITERAL_ARGHELP) ||
 608                    !(opts->flags & PARSE_OPT_NOARG))
 609                        pos += usage_argh(opts, outfile);
 610
 611                if (pos <= USAGE_OPTS_WIDTH)
 612                        pad = USAGE_OPTS_WIDTH - pos;
 613                else {
 614                        fputc('\n', outfile);
 615                        pad = USAGE_OPTS_WIDTH;
 616                }
 617                fprintf(outfile, "%*s%s\n", pad + USAGE_GAP, "", _(opts->help));
 618        }
 619        fputc('\n', outfile);
 620
 621        if (!err && ctx && ctx->flags & PARSE_OPT_SHELL_EVAL)
 622                fputs("EOF\n", outfile);
 623
 624        return PARSE_OPT_HELP;
 625}
 626
 627void NORETURN usage_with_options(const char * const *usagestr,
 628                        const struct option *opts)
 629{
 630        usage_with_options_internal(NULL, usagestr, opts, 0, 1);
 631        exit(129);
 632}
 633
 634void NORETURN usage_msg_opt(const char *msg,
 635                   const char * const *usagestr,
 636                   const struct option *options)
 637{
 638        fprintf(stderr, "%s\n\n", msg);
 639        usage_with_options(usagestr, options);
 640}
 641
 642static int parse_options_usage(struct parse_opt_ctx_t *ctx,
 643                               const char * const *usagestr,
 644                               const struct option *opts, int err)
 645{
 646        return usage_with_options_internal(ctx, usagestr, opts, 0, err);
 647}
 648
 649#undef opterror
 650int opterror(const struct option *opt, const char *reason, int flags)
 651{
 652        if (flags & OPT_SHORT)
 653                return error("switch `%c' %s", opt->short_name, reason);
 654        if (flags & OPT_UNSET)
 655                return error("option `no-%s' %s", opt->long_name, reason);
 656        return error("option `%s' %s", opt->long_name, reason);
 657}