winix/winixd/core/httpsimpleparser.cpp

/*
 * This file is a part of Winix
 * and is distributed under the 2-Clause BSD licence.
 * Author: Tomasz Sowa <t.sowa@ttmath.org>
 */

/* 
 * Copyright (c) 2008-2021, 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:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * 2. 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.
 * 
 * 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 HOLDER 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 "httpsimpleparser.h"
#include "misc.h"
#include "utf8/utf8.h"



namespace Winix
{




void HttpSimpleParser::ToLower(std::wstring & s)
{
	for(wchar_t & c : s)
	{
		if( c>='A' && c<='Z' )
			c = c - 'A' + 'a';
	}
}


bool HttpSimpleParser::IsWhite(int c)
{
	if( c==' ' || c=='\t' )
		return true;
		
return false;
}


void HttpSimpleParser::SkipWhiteChars()
{
	while( IsWhite(last_c) )
		last_c = GetChar();
}





int HttpSimpleParser::ParseHalfHex(int c)
{
	if( c>='a' && c<='z' )
		c += 'A' - 'a';  // to upper case


	if( c >= 'A' )
		c = c - 'A' + 10;
	else
		c = c - '0';
	
	c &= 0xf;
	
	
return c;
}




void HttpSimpleParser::CheckSpecialChar()
{
	if( last_c == '%' )
	{
		int c1 = GetChar();
		int c2 = GetChar();
		
		if( c1==-1 || c2==-1 )
		{
			last_c = -1;
		}
		else
		{	
			c1 = ParseHalfHex(c1);
			c2 = ParseHalfHex(c2);
			
			last_c = (c1 << 4) + c2;
		}
	}
	else
	if( last_c == '+' )
	{
		last_c = ' ';
	}
}



void HttpSimpleParser::ReadName()
{
	// we're checking 'separator' and '=' because the string is allowed not having '=' (the value is optional)
	
	utf8_token.clear();
	last_name.clear();

	for( ; last_c!=-1 && last_c!=separator && last_c!='=' ; last_c = GetChar() )
	{
		if( recognize_special_chars )
			CheckSpecialChar();
		 
		 if( last_c != -1 )
		 {
			if( getchar_returns_utf8_chars )
				utf8_token += last_c;
			else
				last_name += last_c;
		 }
	}
	
	if( getchar_returns_utf8_chars )
		pt::utf8_to_wide(utf8_token, last_name);
	
	if( last_c == '=' )
		last_c = GetChar();
}



void HttpSimpleParser::ReadQuotedValue()
{
	// skipping '"'
	last_c = GetChar();
	utf8_token.clear();
	last_value.clear();
	
	for( ; last_c!=-1 && last_c!='"' ; last_c = GetChar() )
	{
		if( recognize_special_chars )
			CheckSpecialChar();
		
		if( last_c != -1 )
		{
			if( getchar_returns_utf8_chars )
				utf8_token += last_c;
			else
				last_value += last_c;
		}
	}

	if( getchar_returns_utf8_chars )
		pt::utf8_to_wide(utf8_token, last_value);
	
	if( last_c == '"' )
		last_c = GetChar();

	// looking for a separator (skipping)
	for( ; last_c!=-1 && last_c!=separator ; last_c = GetChar() );
	
}


void HttpSimpleParser::ReadNormalValue()
{
	utf8_token.clear();
	last_value.clear();

	for( ; last_c!=-1 && last_c!=separator ; last_c = GetChar() )
	{
		if( recognize_special_chars )
			CheckSpecialChar();

		if( last_c != -1 )
		{
			if( getchar_returns_utf8_chars )
				utf8_token += last_c;
			else
				last_value += last_c;
		}
	}

	if( getchar_returns_utf8_chars )
		pt::utf8_to_wide(utf8_token, last_value);
}


void HttpSimpleParser::ReadValue()
{
	if( skip_white_chars )
		SkipWhiteChars();

	if( value_can_be_quoted && last_c == '"' )
		ReadQuotedValue();
	else
		ReadNormalValue();


	if( last_c == separator )
		last_c = GetChar();
}




/*
 * there can be some important values like passwords so its better
 * to clear them now
 */
void HttpSimpleParser::Clear()
{
	Overwrite(last_name);
	Overwrite(last_value);
	Overwrite(utf8_token);
	last_name.clear();
	last_value.clear();
	utf8_token.clear();
}


void HttpSimpleParser::Parse()
{
	for( last_c = GetChar() ; last_c != -1 ;  )
	{
		last_name.clear();
		last_value.clear();

		if( read_name )
			ReadName();

		ReadValue();

		if( skip_white_chars )
		{		
			TrimWhite(last_name);
			TrimWhite(last_value);
		}

		Parameter(last_name, last_value);	// user definied function	
	}

	Clear();
}





} // namespace Winix