getopt.c

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ifndef _NO_PROTO
#define _NO_PROTO
#endif

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#if !defined (__STDC__) || !__STDC__
/* This is a separate conditional since some stdc systems
   reject `defined (const)'.  */
#ifndef const
#define const
#endif
#endif

#include <stdio.h>


#define GETOPT_INTERFACE_VERSION 2
#if !defined (_LIBC) && defined (__GLIBC__) && __GLIBC__ >= 2
#include <gnu-versions.h>
#if _GNU_GETOPT_INTERFACE_VERSION == GETOPT_INTERFACE_VERSION
#define ELIDE_CODE
#endif
#endif

#ifndef ELIDE_CODE


/* This needs to come after some library #include
   to get __GNU_LIBRARY__ defined.  */
#ifdef	__GNU_LIBRARY__
/* Don't include stdlib.h for non-GNU C libraries because some of them
   contain conflicting prototypes for getopt.  */
#include <stdlib.h>
#include <unistd.h>
#endif	/* GNU C library.  */

#ifdef VMS
#include <unixlib.h>
#if HAVE_STRING_H - 0
#include <string.h>
#endif
#endif

#if defined (WIN32) && !defined (__CYGWIN32__)
/* It's not Unix, really.  See?  Capital letters.  */
#include <windows.h>
#define getpid() GetCurrentProcessId()
#endif

#ifndef _
/* This is for other GNU distributions with internationalized messages.
   When compiling libc, the _ macro is predefined.  */
#ifdef HAVE_LIBINTL_H
# include <libintl.h>
# define _(msgid)	gettext (msgid)
#else
# define _(msgid)	(msgid)
#endif
#endif


#include "getopt.h"


char *optarg = NULL;

/* 1003.2 says this must be 1 before any call.  */
int optind = 1;

/* Formerly, initialization of getopt depended on optind==0, which
   causes problems with re-calling getopt as programs generally don't
   know that. */

int __getopt_initialized = 0;

/* The next char to be scanned in the option-element
   in which the last option character we returned was found.
   This allows us to pick up the scan where we left off.

   If this is zero, or a null string, it means resume the scan
   by advancing to the next ARGV-element.  */

static char *nextchar;

/* Callers store zero here to inhibit the error message
   for unrecognized options.  */

int opterr = 1;

/* Set to an option character which was unrecognized.
   This must be initialized on some systems to avoid linking in the
   system's own getopt implementation.  */

int optopt = '?';

static enum
{
  REQUIRE_ORDER, PERMUTE, RETURN_IN_ORDER
} ordering;

/* Value of POSIXLY_CORRECT environment variable.  */
static char *posixly_correct;

#ifdef	__GNU_LIBRARY__
/* We want to avoid inclusion of string.h with non-GNU libraries
   because there are many ways it can cause trouble.
   On some systems, it contains special magic macros that don't work
   in GCC.  */
#include <string.h>
#define	my_index	strchr
#else

/* Avoid depending on library functions or files
   whose names are inconsistent.  */

char *getenv ();

static char *
my_index (str, chr)
     const char *str;
     int chr;
{
  while (*str)
    {
      if (*str == chr)
	return (char *) str;
      str++;
    }
  return 0;
}

/* If using GCC, we can safely declare strlen this way.
   If not using GCC, it is ok not to declare it.  */
#ifdef __GNUC__
/* Note that Motorola Delta 68k R3V7 comes with GCC but not stddef.h.
   That was relevant to code that was here before.  */
#if !defined (__STDC__) || !__STDC__
/* gcc with -traditional declares the built-in strlen to return int,
   and has done so at least since version 2.4.5. -- rms.  */
extern int strlen (const char *);
#endif /* not __STDC__ */
#endif /* __GNUC__ */

#endif /* not __GNU_LIBRARY__ */

/* Handle permutation of arguments.  */

/* Describe the part of ARGV that contains non-options that have
   been skipped.  `first_nonopt' is the index in ARGV of the first of them;
   `last_nonopt' is the index after the last of them.  */

static int first_nonopt;
static int last_nonopt;

#ifdef _LIBC
/* Bash 2.0 gives us an environment variable containing flags
   indicating ARGV elements that should not be considered arguments.  */

static const char *nonoption_flags;
static int nonoption_flags_len;

static int original_argc;
static char *const *original_argv;

/* Make sure the environment variable bash 2.0 puts in the environment
   is valid for the getopt call we must make sure that the ARGV passed
   to getopt is that one passed to the process.  */
static void store_args (int argc, char *const *argv) __attribute__ ((unused));
static void
store_args (int argc, char *const *argv)
{
  /* XXX This is no good solution.  We should rather copy the args so
     that we can compare them later.  But we must not use malloc(3).  */
  original_argc = argc;
  original_argv = argv;
}
text_set_element (__libc_subinit, store_args);
#endif


#if defined (__STDC__) && __STDC__
static void exchange (char **);
#endif

static void
exchange (argv)
     char **argv;
{
  int bottom = first_nonopt;
  int middle = last_nonopt;
  int top = optind;
  char *tem;


  while (top > middle && middle > bottom)
    {
      if (top - middle > middle - bottom)
	{
	  /* Bottom segment is the short one.  */
	  int len = middle - bottom;
	  register int i;

	  /* Swap it with the top part of the top segment.  */
	  for (i = 0; i < len; i++)
	    {
	      tem = argv[bottom + i];
	      argv[bottom + i] = argv[top - (middle - bottom) + i];
	      argv[top - (middle - bottom) + i] = tem;
	    }
	  /* Exclude the moved bottom segment from further swapping.  */
	  top -= len;
	}
      else
	{
	  /* Top segment is the short one.  */
	  int len = top - middle;
	  register int i;

	  /* Swap it with the bottom part of the bottom segment.  */
	  for (i = 0; i < len; i++)
	    {
	      tem = argv[bottom + i];
	      argv[bottom + i] = argv[middle + i];
	      argv[middle + i] = tem;
	    }
	  /* Exclude the moved top segment from further swapping.  */
	  bottom += len;
	}
    }

  /* Update records for the slots the non-options now occupy.  */

  first_nonopt += (optind - last_nonopt);
  last_nonopt = optind;
}

/* Initialize the internal data when the first call is made.  */

#if defined (__STDC__) && __STDC__
static const char *_getopt_initialize (int, char *const *, const char *);
#endif
static const char *
_getopt_initialize (argc, argv, optstring)
     int argc;
     char *const *argv;
     const char *optstring;
{

  first_nonopt = last_nonopt = optind = 1;

  nextchar = NULL;

  posixly_correct = getenv ("POSIXLY_CORRECT");

  /* Determine how to handle the ordering of options and nonoptions.  */

  if (optstring[0] == '-')
    {
      ordering = RETURN_IN_ORDER;
      ++optstring;
    }
  else if (optstring[0] == '+')
    {
      ordering = REQUIRE_ORDER;
      ++optstring;
    }
  else if (posixly_correct != NULL)
    ordering = REQUIRE_ORDER;
  else
    ordering = PERMUTE;

#ifdef _LIBC
  if (posixly_correct == NULL
      && argc == original_argc && argv == original_argv)
    {
      char var[100];
      sprintf (var, "_%d_GNU_nonoption_argv_flags_", getpid ());
      nonoption_flags = getenv (var);
      if (nonoption_flags == NULL)
	nonoption_flags_len = 0;
      else
	nonoption_flags_len = strlen (nonoption_flags);
    }
  else
    nonoption_flags_len = 0;
#endif

  return optstring;
}


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

#ifdef _LIBC
#define NONOPTION_P (argv[optind][0] != '-' || argv[optind][1] == '\0'	      \
		     || (optind < nonoption_flags_len			      \
			 && 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] == '-'));
    }


  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;