networkmessage.php

<?php
/**
 * Copyright (C) 2012 Rafael Canovas
 * 
 * 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 3 of the License, 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, see <http://www.gnu.org/licenses/>.
**/

class NetworkMessage
{
	private $buffer = '';
	private $readPos = 0;
	
	public function __construct($buffer = '') {
		$this->buffer = $buffer;
	}

	public function getReadPos() {return $this->readPos;}
	public function getLength() {return strlen($this->buffer);}
	
	public function putByte($v)
	{
		$this->buffer .= pack('C', $v);
	}
	public function putU16($v)
	{
		$this->buffer .= pack('v', $v);
	}
	public function putU32($v)
	{
		$this->buffer .= pack('V', $v);
	}
	public function putString($s)
	{
		$this->putU16(strlen($s));
		$this->buffer .= $s;
	}
	
	public function getByte()
	{
		$v = unpack('C', $this->buffer[$this->readPos]);
		$this->readPos++;
		return $v[1];
	}	
	public function getU16()
	{
		$v = unpack('v', substr($this->buffer, $this->readPos, 2));
		$this->readPos += 2;
		return $v[1];
	}
	public function getU32()
	{
		$v = unpack('V', substr($this->buffer, $this->readPos, 4));
		$this->readPos += 4;
		return $v[1];
	}
	public function getString($length = false)
	{
		if($length === false) {
			$length = $this->getU16();
		}
		
		$v = substr($this->buffer, $this->readPos, $length);
		$this->readPos += $length;
		return $v;
	}
	
	public function skipBytes($count)
	{
		$this->readPos += $count;
	}

	public function __toString() {
		// Prepare a real packet for output
		return pack('v', strlen($this->buffer)) . $this->buffer;
	}
}

class NetworkMessageIterator implements Iterator
{
	public function __construct(NetworkMessage &$msg)
	{
		$this->msg = $msg;		
	}

    function current() {}
    function key() {}
    function next() {}
    function rewind() {}

    function valid() {
    	return $this->msg->getReadPos() < $this->msg->getLength();
    }
}