Protocol.php

<?php

/*	EPP Client class for PHP, Copyright 2005 CentralNic Ltd
	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 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, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/**
* Low-level functions useful for both EPP clients and servers
* @package Net_EPP
* @version 0.0.4
* @author Gavin Brown <gavin.brown@nospam.centralnic.com>
* @revision $Id: Protocol.php,v 1.4 2011/06/28 09:48:02 gavin Exp $
*/

require_once('PEAR.php');

/**
* Low-level functions useful for both EPP clients and servers
* @package Net_EPP
*/
class Net_EPP_Protocol {

	/**
	* get an EPP frame from the remote peer
	* @param resource $socket a socket connected to the remote peer
	* @return PEAR_Error|string either an error or a string
	*/
	static function getFrame($socket) {
		if (@feof($socket)) return new PEAR_Error('connection closed (socket is EOF)');

		$hdr = @fread($socket, 4);

		if (empty($hdr) && feof($socket)) {
			return new PEAR_Error('connection closed (no header received and socket is EOF)');

		} elseif (false === $hdr) {
			return new PEAR_Error('Error reading from peer: '.$php_errormsg);

		} else {
			$unpacked = unpack('N', $hdr);
			$length = $unpacked[1];
			if ($length < 5) {
				return new PEAR_Error(sprintf('Got a bad frame header length of %d bytes from peer', $length));

			} else {
				$length -= 4; // discard the length of the header itself

				// sometimes the socket can be buffered with a limit below the frame
				// length, so we continually read from the socket until we get the full frame:
				$frame = '';
				while (strlen($frame) < $length) $frame .= fread($socket, ($length));

				if (strlen($frame) > $length) {
					return new PEAR_Error(sprintf("Frame length (%d bytes) doesn't match header (%d bytes)", strlen($frame), ($length)));

				} else {
					return $frame;