getopt_internal.c

mgcp协议源代码。支持多种编码：g711

   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;
{
  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.  */
#ifdef _LIBC
#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 & 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
	      /* Second or later nonexact match found.  */
	      ambig = 1;
	  }

      if (ambig && !exact)
	{
	  if (opterr)
	    fprintf (stderr, _("%s: option `%s' is ambiguous\n"),
		     argv[0], argv[optind]);
	  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 (opterr)
		   {
		   if (argv[optind - 1][1] == '-')
		    /* --option */
		    fprintf (stderr,
		     _("%s: option `--%s' doesn't allow an argument\n"),
		     argv[0], pfound->name);
		   else
		      {	
		    /* +option or -option */
		    fprintf (stderr,
		     _("%s: option `%c%s' doesn't allow an argument\n"),
		     argv[0], argv[optind - 1][0], pfound->name);
                      }
		    }
		  nextchar += strlen (nextchar);

		  optopt = pfound->val;
		  return '?';
		}
	    }
	  else if (pfound->has_arg == 1)
	    {
	      if (optind < argc)
		optarg = argv[optind++];
	      else
		{
		  if (opterr)
		    fprintf (stderr,
			   _("%s: option `%s' requires an argument\n"),
			   argv[0], argv[optind - 1]);
		  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 (opterr)
	    {
	      if (argv[optind][1] == '-')
		/* --option */
		fprintf (stderr, _("%s: unrecognized option `--%s'\n"),
			 argv[0], nextchar);
	      else
		/* +option or -option */
		fprintf (stderr, _("%s: unrecognized option `%c%s'\n"),
			 argv[0], argv[optind][0], nextchar);
	    }
	  nextchar = (char *) "";
	  optind++;
	  optopt = 0;
	  return '?';
	}
    }

  /* Look at and handle the next short option-character.  */

  {
    char c = *nextchar++;
    char *temp = my_index (optstring, c);

    /* Increment `optind' when we start to process its last character.  */
    if (*nextchar == '\0')
      ++optind;

    if (temp == NULL || c == ':')
      {
	if (opterr)
	  {
	    if (posixly_correct)
	      /* 1003.2 specifies the format of this message.  */
	      fprintf (stderr, _("%s: illegal option -- %c\n"),
		       argv[0], c);
	    else
	      fprintf (stderr, _("%s: invalid option -- %c\n"),
		       argv[0], c);
	  }
	optopt = c;
	return '?';
      }
    /* Convenience. Treat POSIX -W foo same as long option --foo */
    if (temp[0] == 'W' && temp[1] == ';')
      {
	char *nameend;
	const struct option *p;
	const struct option *pfound = NULL;
	int exact = 0;
	int ambig = 0;
	int indfound = 0;
	int option_index;

	/* This is an option that requires an argument.  */
	if (*nextchar != '\0')
	  {
	    optarg = nextchar;
	    /* If we end this ARGV-element by taking the rest as an arg,
	       we must advance to the next element now.  */
	    optind++;
	  }
	else if (optind == argc)
	  {
	    if (opterr)
	      {
		/* 1003.2 specifies the format of this message.  */
		fprintf (stderr, _("%s: option requires an argument -- %c\n"),
			 argv[0], c);
	      }
	    optopt = c;
	    if (optstring[0] == ':')
	      c = ':';
	    else
	      c = '?';
	    return c;
	  }
	else
	  /* We already incremented `optind' once;
	     increment it again when taking next ARGV-elt as argument.  */
	  optarg = argv[optind++];

	/* optarg is now the argument, see if it's in the
	   table of longopts.  */

	for (nextchar = nameend = optarg; *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) == 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
		/* Second or later nonexact match found.  */
		ambig = 1;
	    }
	if (ambig && !exact)
	  {
	    if (opterr)
	      fprintf (stderr, _("%s: option `-W %s' is ambiguous\n"),
		       argv[0], argv[optind]);
	    nextchar += strlen (nextchar);
	    optind++;
	    return '?';
	  }
	if (pfound != NULL)
	  {
	    option_index = indfound;
	    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 (opterr)
		      fprintf (stderr, _("\
%s: option `-W %s' doesn't allow an argument\n"),
			       argv[0], pfound->name);

		    nextchar += strlen (nextchar);
		    return '?';
		  }
	      }
	    else if (pfound->has_arg == 1)
	      {
		if (optind < argc)
		  optarg = argv[optind++];
		else
		  {
		    if (opterr)
		      fprintf (stderr,
			       _("%s: option `%s' requires an argument\n"),
			       argv[0], argv[optind - 1]);
		    nextchar += strlen (nextchar);
		    return optstring[0] == ':' ? ':' : '?';
		  }
	      }
	    nextchar += strlen (nextchar);
	    if (longind != NULL)
	      *longind = option_index;
	    if (pfound->flag)
	      {
		*(pfound->flag) = pfound->val;
		return 0;
	      }
	    return pfound->val;
	  }
	  nextchar = NULL;
	  return 'W';	/* Let the application handle it.   */
      }
    if (temp[1] == ':')
      {
	if (temp[2] == ':')
	  {
	    /* This is an option that accepts an argument optionally.  */
	    if (*nextchar != '\0')
	      {
		optarg = nextchar;
		optind++;
	      }
	    else
	      optarg = NULL;
	    nextchar = NULL;
	  }
	else
	  {
	    /* This is an option that requires an argument.  */
	    if (*nextchar != '\0')
	      {
		optarg = nextchar;
		/* If we end this ARGV-element by taking the rest as an arg,
		   we must advance to the next element now.  */
		optind++;
	      }
	    else if (optind == argc)
	      {
		if (opterr)
		  {
		    /* 1003.2 specifies the format of this message.  */
		    fprintf (stderr,
			   _("%s: option requires an argument -- %c\n"),
			   argv[0], c);
		  }
		optopt = c;
		if (optstring[0] == ':')
		  c = ':';
		else
		  c = '?';
	      }
	    else
	      /* We already incremented `optind' once;
		 increment it again when taking next ARGV-elt as argument.  */
	      optarg = argv[optind++];
	    nextchar = NULL;
	  }
      }
    return c;
  }
}

#endif	/* Not ELIDE_CODE.  */