getopt.c

在win2000sp4 + VM6基本稳定。 原理不多说了

      && argc == __libc_argc && argv == __libc_argv)
    {
      if (nonoption_flags_max_len == 0)
        {
          if (__getopt_nonoption_flags == NULL
              || __getopt_nonoption_flags[0] == '\0')
            nonoption_flags_max_len = -1;
          else
            {
              const char *orig_str = __getopt_nonoption_flags;
              int len = nonoption_flags_max_len = strlen (orig_str);
              if (nonoption_flags_max_len < argc)
                nonoption_flags_max_len = argc;
              __getopt_nonoption_flags =
                (char *) malloc (nonoption_flags_max_len);
              if (__getopt_nonoption_flags == NULL)
                nonoption_flags_max_len = -1;
              else
                memset (__mempcpy (__getopt_nonoption_flags, orig_str, len),
                        '\0', nonoption_flags_max_len - len);
            }
        }
      nonoption_flags_len = nonoption_flags_max_len;
    }
  else
    nonoption_flags_len = 0;
#endif

  return optstring;
}

/* Scan elements of ARGV (whose length is ARGC) for option characters
   given in OPTSTRING.

   If an element of ARGV starts with '-', and is not exactly "-" or "--",
   then it is an option element.  The characters of this element
   (aside from the initial '-') are option characters.  If `getopt'
   is called repeatedly, it returns successively each of the option characters
   from each of the option elements.

   If `getopt' finds another option character, it returns that character,
   updating `optind' and `nextchar' so that the next call to `getopt' can
   resume the scan with the following option character or ARGV-element.

   If there are no more option characters, `getopt' returns -1.
   Then `optind' is the index in ARGV of the first ARGV-element
   that is not an option.  (The ARGV-elements have been permuted
   so that those that are not options now come last.)

   OPTSTRING is a string containing the legitimate option characters.
   If an option character is seen that is not listed in OPTSTRING,
   return '?' after printing an error message.  If you set `opterr' to
   zero, the error message is suppressed but we still return '?'.

   If a char in OPTSTRING is followed by a colon, that means it wants an arg,
   so the following text in the same ARGV-element, or the text of the following
   ARGV-element, is returned in `optarg'.  Two colons mean an option that
   wants an optional arg; if there is text in the current ARGV-element,
   it is returned in `optarg', otherwise `optarg' is set to zero.

   If OPTSTRING starts with `-' or `+', it requests different methods of
   handling the non-option ARGV-elements.
   See the comments about RETURN_IN_ORDER and REQUIRE_ORDER, above.

   Long-named options begin with `--' instead of `-'.
   Their names may be abbreviated as long as the abbreviation is unique
   or is an exact match for some defined option.  If they have an
   argument, it follows the option name in the same ARGV-element, separated
   from the option name by a `=', or else the in next ARGV-element.
   When `getopt' finds a long-named option, it returns 0 if that option's
   `flag' field is nonzero, the value of the option's `val' field
   if the `flag' field is zero.

   The elements of ARGV aren't really const, because we permute them.
   But we pretend they're const in the prototype to be compatible
   with other systems.

   LONGOPTS is a vector of `struct option' terminated by an
   element containing a name which is zero.

   LONGIND returns the index in LONGOPT of the long-named option found.
   It is only valid when a long-named option has been found by the most
   recent call.

   If LONG_ONLY is nonzero, '-' as well as '--' can introduce
   long-named options.  */

int
_getopt_internal (argc, argv, optstring, longopts, longind, long_only)
     int argc;
     char *const *argv;
     const char *optstring;
     const struct option *longopts;
     int *longind;
     int long_only;
{
  int print_errors = opterr;
  if (optstring[0] == ':')
    print_errors = 0;

  if (argc < 1)
    return -1;

  optarg = NULL;

  if (optind == 0 || !__getopt_initialized)
    {
      if (optind == 0)
        optind = 1;     /* Don't scan ARGV[0], the program name.  */
      optstring = _getopt_initialize (argc, argv, optstring);
      __getopt_initialized = 1;
    }

  /* Test whether ARGV[optind] points to a non-option argument.
     Either it does not have option syntax, or there is an environment flag
     from the shell indicating it is not an option.  The later information
     is only used when the used in the GNU libc.  */
#if defined _LIBC && defined USE_NONOPTION_FLAGS
# define NONOPTION_P (argv[optind][0] != '-' || argv[optind][1] == '\0'       \
                      || (optind < nonoption_flags_len                        \
                          && __getopt_nonoption_flags[optind] == '1'))
#else
# define NONOPTION_P (argv[optind][0] != '-' || argv[optind][1] == '\0')
#endif

  if (nextchar == NULL || *nextchar == '\0')
    {
      /* Advance to the next ARGV-element.  */

      /* Give FIRST_NONOPT and LAST_NONOPT rational values if OPTIND has been
         moved back by the user (who may also have changed the arguments).  */
      if (last_nonopt > optind)
        last_nonopt = optind;
      if (first_nonopt > optind)
        first_nonopt = optind;

      if (ordering == PERMUTE)
        {
          /* If we have just processed some options following some non-options,
             exchange them so that the options come first.  */

          if (first_nonopt != last_nonopt && last_nonopt != optind)
            exchange ((char **) argv);
          else if (last_nonopt != optind)
            first_nonopt = optind;

          /* Skip any additional non-options
             and extend the range of non-options previously skipped.  */

          while (optind < argc && NONOPTION_P)
            optind++;
          last_nonopt = optind;
        }

      /* The special ARGV-element `--' means premature end of options.
         Skip it like a null option,
         then exchange with previous non-options as if it were an option,
         then skip everything else like a non-option.  */

      if (optind != argc && !strcmp (argv[optind], "--"))
        {
          optind++;

          if (first_nonopt != last_nonopt && last_nonopt != optind)
            exchange ((char **) argv);
          else if (first_nonopt == last_nonopt)
            first_nonopt = optind;
          last_nonopt = argc;

          optind = argc;
        }

      /* If we have done all the ARGV-elements, stop the scan
         and back over any non-options that we skipped and permuted.  */

      if (optind == argc)
        {
          /* Set the next-arg-index to point at the non-options
             that we previously skipped, so the caller will digest them.  */
          if (first_nonopt != last_nonopt)
            optind = first_nonopt;
          return -1;
        }

      /* If we have come to a non-option and did not permute it,
         either stop the scan or describe it to the caller and pass it by.  */

      if (NONOPTION_P)
        {
          if (ordering == REQUIRE_ORDER)
            return -1;
          optarg = argv[optind++];
          return 1;
        }

      /* We have found another option-ARGV-element.
         Skip the initial punctuation.  */

      nextchar = (argv[optind] + 1
                  + (longopts != NULL && argv[optind][1] == '-'));
    }

  /* Decode the current option-ARGV-element.  */

  /* Check whether the ARGV-element is a long option.

     If long_only and the ARGV-element has the form "-f", where f is
     a valid short option, don't consider it an abbreviated form of
     a long option that starts with f.  Otherwise there would be no
     way to give the -f short option.

     On the other hand, if there's a long option "fubar" and
     the ARGV-element is "-fu", do consider that an abbreviation of
     the long option, just like "--fu", and not "-f" with arg "u".

     This distinction seems to be the most useful approach.  */

  if (longopts != NULL
      && (argv[optind][1] == '-'
          || (long_only && (argv[optind][2] || !my_index (optstring, argv[optind][1])))))
    {
      char *nameend;
      const struct option *p;
      const struct option *pfound = NULL;
      int exact = 0;
      int ambig = 0;
      int indfound = -1;
      int option_index;

      for (nameend = nextchar; *nameend && *nameend != '='; nameend++)
        /* Do nothing.  */ ;

      /* Test all long options for either exact match
         or abbreviated matches.  */
      for (p = longopts, option_index = 0; p->name; p++, option_index++)
        if (!strncmp (p->name, nextchar, nameend - nextchar))
          {
            if ((unsigned int) (nameend - nextchar)
                == (unsigned int) strlen (p->name))
              {
                /* Exact match found.  */
                pfound = p;
                indfound = option_index;
                exact = 1;
                break;
              }
            else if (pfound == NULL)
              {
                /* First nonexact match found.  */
                pfound = p;
                indfound = option_index;
              }
            else if (long_only
                     || pfound->has_arg != p->has_arg
                     || pfound->flag != p->flag
                     || pfound->val != p->val)
              /* Second or later nonexact match found.  */
              ambig = 1;
          }

      if (ambig && !exact)
        {
          if (print_errors)
            {
#if defined _LIBC && defined USE_IN_LIBIO
              char *buf;

              __asprintf (&buf, _("%s: option `%s' is ambiguous\n"),
                          argv[0], argv[optind]);

              if (_IO_fwide (stderr, 0) > 0)
                __fwprintf (stderr, L"%s", buf);
              else
                fputs (buf, stderr);

              free (buf);
#else
              fprintf (stderr, _("%s: option `%s' is ambiguous\n"),
                       argv[0], argv[optind]);
#endif
            }
          nextchar += strlen (nextchar);
          optind++;
          optopt = 0;
          return '?';
        }

      if (pfound != NULL)
        {
          option_index = indfound;
          optind++;
          if (*nameend)
            {
              /* Don't test has_arg with >, because some C compilers don't
                 allow it to be used on enums.  */
              if (pfound->has_arg)
                optarg = nameend + 1;
              else
                {
                  if (print_errors)
                    {
#if defined _LIBC && defined USE_IN_LIBIO
                      char *buf;
#endif

                      if (argv[optind - 1][1] == '-')
                        {
                          /* --option */
#if defined _LIBC && defined USE_IN_LIBIO
                          __asprintf (&buf, _("\
%s: option `--%s' doesn't allow an argument\n"),
                                      argv[0], pfound->name);
#else
                          fprintf (stderr, _("\
%s: option `--%s' doesn't allow an argument\n"),
                                   argv[0], pfound->name);
#endif
                        }
                      else
                        {
                          /* +option or -option */
#if defined _LIBC && defined USE_IN_LIBIO
                          __asprintf (&buf, _("\
%s: option `%c%s' doesn't allow an argument\n"),
                                      argv[0], argv[optind - 1][0],
                                      pfound->name);
#else
                          fprintf (stderr, _("\
%s: option `%c%s' doesn't allow an argument\n"),
                                   argv[0], argv[optind - 1][0], pfound->name);
#endif
                        }

#if defined _LIBC && defined USE_IN_LIBIO
                      if (_IO_fwide (stderr, 0) > 0)
                        __fwprintf (stderr, L"%s", buf);
                      else
                        fputs (buf, stderr);

                      free (buf);
#endif
                    }

                  nextchar += strlen (nextchar);

                  optopt = pfound->val;
                  return '?';
                }
            }
          else if (pfound->has_arg == 1)
            {
              if (optind < argc)
                optarg = argv[optind++];
              else
                {
                  if (print_errors)
                    {
#if defined _LIBC && defined USE_IN_LIBIO
                      char *buf;

                      __asprintf (&buf,
                                  _("%s: option `%s' requires an argument\n"),
                                  argv[0], argv[optind - 1]);

                      if (_IO_fwide (stderr, 0) > 0)
                        __fwprintf (stderr, L"%s", buf);
                      else
                        fputs (buf, stderr);

                      free (buf);
#else
                      fprintf (stderr,
                               _("%s: option `%s' requires an argument\n"),
                               argv[0], argv[optind - 1]);
#endif
                    }
                  nextchar += strlen (nextchar);
                  optopt = pfound->val;
                  return optstring[0] == ':' ? ':' : '?';
                }
            }
          nextchar += strlen (nextchar);
          if (longind != NULL)
            *longind = option_index;
          if (pfound->flag)
            {
              *(pfound->flag) = pfound->val;
              return 0;
            }
          return pfound->val;
        }

      /* Can't find it as a long option.  If this is not getopt_long_only,
         or the option starts with '--' or is not a valid short
         option, then it's an error.
         Otherwise interpret it as a short option.  */
      if (!long_only || argv[optind][1] == '-'
          || my_index (optstring, *nextchar) == NULL)
        {
          if (print_errors)
            {
#if defined _LIBC && defined USE_IN_LIBIO
              char *buf;
#endif

              if (argv[optind][1] == '-')
                {
                  /* --option */
#if defined _LIBC && defined USE_IN_LIBIO
                  __asprintf (&buf, _("%s: unrecognized option `--%s'\n"),
                              argv[0], nextchar);
#else
                  fprintf (stderr, _("%s: unrecognized option `--%s'\n"),
                           argv[0], nextchar);
#endif
                }
              else
                {
                  /* +option or -option */
#if defined _LIBC && defined USE_IN_LIBIO