getopt.c

GNUnet是一个安全的点对点网络框架

/* Getopt for GNU.
   NOTE: getopt is now part of the C library, so if you don't know what
   "Keep this file name-space clean" means, talk to [e-mail]
   before changing it!

   Copyright (C) 1987, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97
     Free Software Foundation, Inc.

NOTE: The canonical source of this file is maintained with the GNU C Library.
Bugs can be reported to [e-mail].

This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
USA.


This code was heavily modified for GNUnet.
Copyright (C) 2006 Christian Grothoff
*/

/**
 * @file util/getopt/getopt.c
 * @brief GNU style option parsing
 *
 * TODO: get rid of statics (make reentrant) and
 * replace main GNU getopt parser with one that
 * actually fits our API.
 */

#include "platform.h"
#include "gnunet_util_error.h"
#include "gnunet_util_string.h"
#include "gnunet_util_getopt.h"

#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

/* Describe the long-named options requested by the application.
   The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
   of `struct GNoption' terminated by an element containing a name which is
   zero.

   The field `has_arg' is:
   no_argument  	(or 0) if the option does not take an argument,
   required_argument  (or 1) if the option requires an argument,
   optional_argument   (or 2) if the option takes an optional argument.

   If the field `flag' is not NULL, it points to a variable that is set
   to the value given in the field `val' when the option is found, but
   left unchanged if the option is not found.

   To have a long-named option do something other than set an `int' to
   a compiled-in constant, such as set a value from `GNoptarg', set the
   option's `flag' field to zero and its `val' field to a nonzero
   value (the equivalent single-letter option character, if there is
   one).  For long options that have a zero `flag' field, `getopt'
   returns the contents of the `val' field.  */

struct GNoption
{
  const char *name;
  /* has_arg can't be an enum because some compilers complain about
     type mismatches in all the code that assumes it is an int.  */
  int has_arg;
  int *flag;
  int val;
};


/* This version of `getopt' appears to the caller like standard Unix `getopt'
   but it behaves differently for the user, since it allows the user
   to intersperse the options with the other arguments.

   As `getopt' works, it permutes the elements of ARGV so that,
   when it is done, all the options precede everything else.  Thus
   all application programs are extended to handle flexible argument order.

   Setting the environment variable POSIXLY_CORRECT disables permutation.
   Then the behavior is completely standard.

   GNU application programs can use a third alternative mode in which
   they can distinguish the relative order of options and other arguments.  */

/* For communication from `getopt' to the caller.
   When `getopt' finds an option that takes an argument,
   the argument value is returned here.
   Also, when `ordering' is RETURN_IN_ORDER,
   each non-option ARGV-element is returned here.  */

static char *GNoptarg = NULL;

/* Index in ARGV of the next element to be scanned.
   This is used for communication to and from the caller
   and for communication between successive calls to `getopt'.

   On entry to `getopt', zero means this is the first call; initialize.

   When `getopt' returns -1, this is the index of the first of the
   non-option elements that the caller should itself scan.

   Otherwise, `GNoptind' communicates from one call to the next
   how much of ARGV has been scanned so far.  */

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

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

static 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.  */

static int GNopterr = 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.  */

static int GNoptopt = '?';

/* Describe how to deal with options that follow non-option ARGV-elements.

   If the caller did not specify anything,
   the default is REQUIRE_ORDER if the environment variable
   POSIXLY_CORRECT is defined, PERMUTE otherwise.

   REQUIRE_ORDER means don't recognize them as options;
   stop option processing when the first non-option is seen.
   This is what Unix does.
   This mode of operation is selected by either setting the environment
   variable POSIXLY_CORRECT, or using `+' as the first character
   of the list of option characters.

   PERMUTE is the default.  We GNUNET_permute the contents of ARGV as we scan,
   so that eventually all the non-options are at the end.  This allows options
   to be given in any order, even with programs that were not written to
   expect this.

   RETURN_IN_ORDER is an option available to programs that were written
   to expect GNoptions and other ARGV-elements in any order and that care about
   the ordering of the two.  We describe each non-option ARGV-element
   as if it were the argument of an option with character code 1.
   Using `-' as the first character of the list of option characters
   selects this mode of operation.

   The special argument `--' forces an end of option-scanning regardless
   of the value of `ordering'.  In the case of RETURN_IN_ORDER, only
   `--' can cause `getopt' to return -1 with `GNoptind' != ARGC.  */

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.  */

/* Defined in getopt_init.c  */
extern char *__getopt_nonoption_flags;

static int nonoption_flags_max_len;
static int nonoption_flags_len;

static int original_argc;
static char *const *original_argv;

extern pid_t __libc_pid;

/* 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
  __attribute__ ((unused)) store_args_and_env (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_and_env);

# define SWAP_FLAGS(ch1, ch2) \
  if (nonoption_flags_len > 0)  					      \
    {  								      \
      char __tmp = __getopt_nonoption_flags[ch1];  		      \
      __getopt_nonoption_flags[ch1] = __getopt_nonoption_flags[ch2];        \
      __getopt_nonoption_flags[ch2] = __tmp;  			      \
    }
#else /* !_LIBC */
# define SWAP_FLAGS(ch1, ch2)
#endif /* _LIBC */

/* Exchange two adjacent subsequences of ARGV.
   One subsequence is elements [first_nonopt,last_nonopt)
   which contains all the non-options that have been skipped so far.
   The other is elements [last_nonopt,GNoptind), which contains all
   the options processed since those non-options were skipped.

   `first_nonopt' and `last_nonopt' are relocated so that they describe
   the new indices of the non-options in ARGV after they are moved.  */

#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 = GNoptind;
  char *tem;

  /* Exchange the shorter segment with the far end of the longer segment.
     That puts the shorter segment into the right place.
     It leaves the longer segment in the right place overall,
     but it consists of two parts that need to be swapped next.  */

#ifdef _LIBC
  /* First make sure the handling of the `__getopt_nonoption_flags'
     string can work normally.  Our top argument must be in the range
     of the string.  */
  if (nonoption_flags_len > 0 && top >= nonoption_flags_max_len)
    {
      /* We must extend the array.  The user plays games with us and
         presents new arguments.  */
      char *new_str = malloc (top + 1);
      if (new_str == NULL)
        nonoption_flags_len = nonoption_flags_max_len = 0;
      else
        {
          memcpy (new_str, __getopt_nonoption_flags, nonoption_flags_max_len);
          memset (&new_str[nonoption_flags_max_len], '\0',
                  top + 1 - nonoption_flags_max_len);
          nonoption_flags_max_len = top + 1;
          __getopt_nonoption_flags = new_str;
        }
    }
#endif

  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;
              SWAP_FLAGS (bottom + i, top - (middle - bottom) + i);
            }
          /* Exclude the moved bottom segment from further swapping.  */
          top -= len;
        }
      else
        {