Differential D20980 Diff 49991 src/channel/PhutilPHPObjectProtocolChannel.php

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src/channel/PhutilPHPObjectProtocolChannel.php

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				<?php

				/**
				* Channel that transmits PHP objects using PHP serialization. This channel
				* is binary safe.
				*
				* @task protocol Protocol Implementation
				*/
				final class PhutilPHPObjectProtocolChannel extends PhutilProtocolChannel {

				const MODE_LENGTH = 'length';
				const MODE_OBJECT = 'object';

				/**
				* Size of the "length" frame of the protocol in bytes.
				*/
				const SIZE_LENGTH = 4;

				private $mode = self::MODE_LENGTH;
				private $byteLengthOfNextChunk = self::SIZE_LENGTH;
				private $buf = '';


				/* -( Protocol Implementation )-------------------------------------------- */


				/**
				* Encode a message for transmission over the channel. The message should
				* be any serializable PHP object. The entire object will be serialized, so
				* avoid transmitting objects which connect to large graphs of other objects,
				* etc.
				*
				* This channel can transmit class instances, but the receiving end must be
				* running the same version of the code. There are no builtin safeguards
				* to protect against versioning problems in object serialization.
				*
				* Objects are transmitted as:
				*
				* <len><serialized PHP object>
				*
				* ...where <len> is a 4-byte unsigned big-endian integer.
				*
				* @task protocol
				*/
				protected function encodeMessage($message) {
				$message = serialize($message);
				$len = pack('N', strlen($message));
				return "{$len}{$message}";
				}


				/**
				* Decode a message received from the other end of the channel.
				*
				* @task protocol
				*/
				protected function decodeStream($data) {
				$this->buf .= $data;

				$objects = array();
				while (strlen($this->buf) >= $this->byteLengthOfNextChunk) {
				switch ($this->mode) {
				case self::MODE_LENGTH:
				$len = substr($this->buf, 0, self::SIZE_LENGTH);
				$this->buf = substr($this->buf, self::SIZE_LENGTH);

				$this->mode = self::MODE_OBJECT;
				$this->byteLengthOfNextChunk = head(unpack('N', $len));
				break;
				case self::MODE_OBJECT:
				$data = substr($this->buf, 0, $this->byteLengthOfNextChunk);
				$this->buf = substr($this->buf, $this->byteLengthOfNextChunk);

				$obj = @unserialize($data);
				if ($obj === false) {
				throw new Exception(pht('Failed to unserialize object: %s', $data));
				} else {
				$objects[] = $obj;
				}

				$this->mode = self::MODE_LENGTH;
				$this->byteLengthOfNextChunk = self::SIZE_LENGTH;
				break;
				}
				}

				return $objects;
				}

				}