Click here to Skip to main content
Click here to Skip to main content
 
Add your own
alternative version

XGetopt - A Unix-compatible getopt() for MFC and Win32

, 20 May 2003 CPOL
XGetopt provides drop-in Unix-style command line processing for Win32 and MFC applications
// XGetopt.cpp  Version 1.2
//
// Author:  Hans Dietrich
//          hdietrich2@hotmail.com
//
// Description:
//     XGetopt.cpp implements getopt(), a function to parse command lines.
//
// History
//     Version 1.2 - 2003 May 17
//     - Added Unicode support
//
//     Version 1.1 - 2002 March 10
//     - Added example to XGetopt.cpp module header 
//
// This software is released into the public domain.
// You are free to use it in any way you like.
//
// This software is provided "as is" with no expressed
// or implied warranty.  I accept no liability for any
// damage or loss of business that this software may cause.
//
///////////////////////////////////////////////////////////////////////////////


///////////////////////////////////////////////////////////////////////////////
// if you are using precompiled headers then include this line:
#include "stdafx.h"
///////////////////////////////////////////////////////////////////////////////


///////////////////////////////////////////////////////////////////////////////
// if you are not using precompiled headers then include these lines:
//#include <windows.h>
//#include <stdio.h>
//#include <tchar.h>
///////////////////////////////////////////////////////////////////////////////


#include "XGetopt.h"


///////////////////////////////////////////////////////////////////////////////
//
//  X G e t o p t . c p p
//
//
//  NAME
//       getopt -- parse command line options
//
//  SYNOPSIS
//       int getopt(int argc, TCHAR *argv[], TCHAR *optstring)
//
//       extern TCHAR *optarg;
//       extern int optind;
//
//  DESCRIPTION
//       The getopt() function parses the command line arguments. Its
//       arguments argc and argv are the argument count and array as
//       passed into the application on program invocation.  In the case
//       of Visual C++ programs, argc and argv are available via the
//       variables __argc and __argv (double underscores), respectively.
//       getopt returns the next option letter in argv that matches a
//       letter in optstring.  (Note:  Unicode programs should use
//       __targv instead of __argv.  Also, all character and string
//       literals should be enclosed in _T( ) ).
//
//       optstring is a string of recognized option letters;  if a letter
//       is followed by a colon, the option is expected to have an argument
//       that may or may not be separated from it by white space.  optarg
//       is set to point to the start of the option argument on return from
//       getopt.
//
//       Option letters may be combined, e.g., "-ab" is equivalent to
//       "-a -b".  Option letters are case sensitive.
//
//       getopt places in the external variable optind the argv index
//       of the next argument to be processed.  optind is initialized
//       to 0 before the first call to getopt.
//
//       When all options have been processed (i.e., up to the first
//       non-option argument), getopt returns EOF, optarg will point
//       to the argument, and optind will be set to the argv index of
//       the argument.  If there are no non-option arguments, optarg
//       will be set to NULL.
//
//       The special option "--" may be used to delimit the end of the
//       options;  EOF will be returned, and "--" (and everything after it)
//       will be skipped.
//
//  RETURN VALUE
//       For option letters contained in the string optstring, getopt
//       will return the option letter.  getopt returns a question mark (?)
//       when it encounters an option letter not included in optstring.
//       EOF is returned when processing is finished.
//
//  BUGS
//       1)  Long options are not supported.
//       2)  The GNU double-colon extension is not supported.
//       3)  The environment variable POSIXLY_CORRECT is not supported.
//       4)  The + syntax is not supported.
//       5)  The automatic permutation of arguments is not supported.
//       6)  This implementation of getopt() returns EOF if an error is
//           encountered, instead of -1 as the latest standard requires.
//
//  EXAMPLE
//       BOOL CMyApp::ProcessCommandLine(int argc, TCHAR *argv[])
//       {
//           int c;
//
//           while ((c = getopt(argc, argv, _T("aBn:"))) != EOF)
//           {
//               switch (c)
//               {
//                   case _T('a'):
//                       TRACE(_T("option a\n"));
//                       //
//                       // set some flag here
//                       //
//                       break;
//
//                   case _T('B'):
//                       TRACE( _T("option B\n"));
//                       //
//                       // set some other flag here
//                       //
//                       break;
//
//                   case _T('n'):
//                       TRACE(_T("option n: value=%d\n"), atoi(optarg));
//                       //
//                       // do something with value here
//                       //
//                       break;
//
//                   case _T('?'):
//                       TRACE(_T("ERROR: illegal option %s\n"), argv[optind-1]);
//                       return FALSE;
//                       break;
//
//                   default:
//                       TRACE(_T("WARNING: no handler for option %c\n"), c);
//                       return FALSE;
//                       break;
//               }
//           }
//           //
//           // check for non-option args here
//           //
//           return TRUE;
//       }
//
///////////////////////////////////////////////////////////////////////////////

TCHAR	*optarg;		// global argument pointer
int		optind = 0; 	// global argv index

int getopt(int argc, TCHAR *argv[], TCHAR *optstring)
{
	static TCHAR *next = NULL;
	if (optind == 0)
		next = NULL;

	optarg = NULL;

	if (next == NULL || *next == _T('\0'))
	{
		if (optind == 0)
			optind++;

		if (optind >= argc || argv[optind][0] != _T('-') || argv[optind][1] == _T('\0'))
		{
			optarg = NULL;
			if (optind < argc)
				optarg = argv[optind];
			return EOF;
		}

		if (_tcscmp(argv[optind], _T("--")) == 0)
		{
			optind++;
			optarg = NULL;
			if (optind < argc)
				optarg = argv[optind];
			return EOF;
		}

		next = argv[optind];
		next++;		// skip past -
		optind++;
	}

	TCHAR c = *next++;
	TCHAR *cp = _tcschr(optstring, c);

	if (cp == NULL || c == _T(':'))
		return _T('?');

	cp++;
	if (*cp == _T(':'))
	{
		if (*next != _T('\0'))
		{
			optarg = next;
			next = NULL;
		}
		else if (optind < argc)
		{
			optarg = argv[optind];
			optind++;
		}
		else
		{
			return _T('?');
		}
	}

	return c;
}

By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.

If a file you wish to view isn't highlighted, and is a text file (not binary), please let us know and we'll add colourisation support for it.

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Share

About the Author

Hans Dietrich
Software Developer (Senior) Hans Dietrich Software
United States United States
I attended St. Michael's College of the University of Toronto, with the intention of becoming a priest. A friend in the University's Computer Science Department got me interested in programming, and I have been hooked ever since.
 
Recently, I have moved to Los Angeles where I am doing consulting and development work.
 
For consulting and custom software development, please see www.hdsoft.org.






| Advertise | Privacy | Terms of Use | Mobile
Web04 | 2.8.141223.1 | Last Updated 21 May 2003
Article Copyright 2002 by Hans Dietrich
Everything else Copyright © CodeProject, 1999-2014
Layout: fixed | fluid