pikotools/mainparser/mainparser.cpp

/*
 * This file is a part of PikoTools
 * and is distributed under the (new) BSD licence.
 * Author: Tomasz Sowa <t.sowa@ttmath.org>
 */

/* 
 * Copyright (c) 2011-2012, Tomasz Sowa
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *  * Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *    
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *    
 *  * Neither the name Tomasz Sowa nor the names of contributors to this
 *    project may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */


#include "mainparser.h"
#include <string.h>


namespace PT
{


MainParser::MainParser()
{
	argsize = 0;
	arg     = 0;
	Reset();
}



MainParser::MainParser(int argc, const char ** argv)
{
	Set(argc, argv);
	Reset();
}



void MainParser::Set(int argc, const char ** argv)
{
	argsize = argc;
	arg     = argv;
	Reset();
}



void MainParser::Reset()
{
	argindex = 1;
	offset   = 0;
	has_single_param = false;
	has_double_param = false;
}



char MainParser::GetSingleParam()
{
	if( !has_single_param )
		return 0;

	if( last_single_param != 0 )
		return last_single_param;

	Advance();

	if( argindex >= argsize )
		return 0;
	
	last_single_param = arg[argindex][offset];
	offset += 1;

return last_single_param;
}



bool MainParser::IsSingleParam(char c)
{
	return GetSingleParam() == c;
}


const char * MainParser::GetDoubleParam()
{
	empty = 0;

	if( !has_double_param )
		return &empty;

	if( last_double_param != &empty )
		return last_double_param;

	Advance();

	if( argindex >= argsize )
		return &empty;
	
	last_double_param = &arg[argindex][offset];
	offset    = 0;
	argindex += 1;

return last_double_param;
}


bool MainParser::IsDoubleParam(const char * param)
{
	return strcmp(GetDoubleParam(), param) == 0;
}


const char * MainParser::GetValue()
{
	empty = 0;
	Advance();

	if( argindex >= argsize )
		return &empty;
	
	const char * value = &arg[argindex][offset];
	offset    = 0;
	argindex += 1;
	has_single_param = false;
	has_double_param = false;

return value;
}



bool MainParser::NextParam()
{
	bool was_single_param = has_single_param;
	has_single_param = false;
	has_double_param = false;
	last_single_param = 0;
	last_double_param = &empty;
	empty = 0;

	if( Advance() )
		was_single_param = false;

	if( argindex >= argsize )
		return false;

	if( arg[argindex][offset]=='-' )
	{
		if( arg[argindex][offset+1]=='-' )
		{
			has_double_param = true;
			offset += 2;
		}
		else
		{
			has_single_param = true;
			offset += 1;
		}
	}
	else
	{
		if( was_single_param )
			has_single_param = true;
	}

return has_single_param || has_double_param;
}



bool MainParser::IsEnd()
{
	Advance();

return argindex >= argsize;
}



bool MainParser::HasSingleParam()
{
	return has_single_param;
}



bool MainParser::HasDoubleParam()
{
	return has_double_param;
}



bool MainParser::Advance()
{
bool was_incremented = false;

	while( argindex < argsize && arg[argindex][offset] == 0 )
	{
		offset    = 0;
		argindex += 1;
		was_incremented = true;
	}

return was_incremented;
}


} // namespace