web/Zend/Amf/Util/BinaryStream.php
changeset 0 4eba9c11703f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/Zend/Amf/Util/BinaryStream.php	Mon Dec 13 18:29:26 2010 +0100
@@ -0,0 +1,285 @@
+<?php
+/**
+ * Zend Framework
+ *
+ * LICENSE
+ *
+ * This source file is subject to the new BSD license that is bundled
+ * with this package in the file LICENSE.txt.
+ * It is also available through the world-wide-web at this URL:
+ * http://framework.zend.com/license/new-bsd
+ * If you did not receive a copy of the license and are unable to
+ * obtain it through the world-wide-web, please send an email
+ * to license@zend.com so we can send you a copy immediately.
+ *
+ * @category   Zend
+ * @package    Zend_Amf
+ * @subpackage Util
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ * @version    $Id: BinaryStream.php 22101 2010-05-04 20:07:13Z matthew $
+ */
+
+/**
+ * Utility class to walk through a data stream byte by byte with conventional names
+ *
+ * @package    Zend_Amf
+ * @subpackage Util
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ */
+class Zend_Amf_Util_BinaryStream
+{
+    /**
+     * @var string Byte stream
+     */
+    protected $_stream;
+
+    /**
+     * @var int Length of stream
+     */
+    protected $_streamLength;
+
+    /**
+     * @var bool BigEndian encoding?
+     */
+    protected $_bigEndian;
+
+    /**
+     * @var int Current position in stream
+     */
+    protected $_needle;
+
+    /**
+     * Constructor
+     *
+     * Create a reference to a byte stream that is going to be parsed or created
+     * by the methods in the class. Detect if the class should use big or
+     * little Endian encoding.
+     *
+     * @param  string $stream use '' if creating a new stream or pass a string if reading.
+     * @return void
+     */
+    public function __construct($stream)
+    {
+        if (!is_string($stream)) {
+            require_once 'Zend/Amf/Exception.php';
+            throw new Zend_Amf_Exception('Inputdata is not of type String');
+        }
+
+        $this->_stream       = $stream;
+        $this->_needle       = 0;
+        $this->_streamLength = strlen($stream);
+        $this->_bigEndian    = (pack('l', 1) === "\x00\x00\x00\x01");
+    }
+
+    /**
+     * Returns the current stream
+     *
+     * @return string
+     */
+    public function getStream()
+    {
+        return $this->_stream;
+    }
+
+    /**
+     * Read the number of bytes in a row for the length supplied.
+     *
+     * @todo   Should check that there are enough bytes left in the stream we are about to read.
+     * @param  int $length
+     * @return string
+     * @throws Zend_Amf_Exception for buffer underrun
+     */
+    public function readBytes($length)
+    {
+        if (($length + $this->_needle) > $this->_streamLength) {
+            require_once 'Zend/Amf/Exception.php';
+            throw new Zend_Amf_Exception('Buffer underrun at needle position: ' . $this->_needle . ' while requesting length: ' . $length);
+        }
+        $bytes = substr($this->_stream, $this->_needle, $length);
+        $this->_needle+= $length;
+        return $bytes;
+    }
+
+    /**
+     * Write any length of bytes to the stream
+     *
+     * Usually a string.
+     *
+     * @param  string $bytes
+     * @return Zend_Amf_Util_BinaryStream
+     */
+    public function writeBytes($bytes)
+    {
+        $this->_stream.= $bytes;
+        return $this;
+    }
+
+    /**
+     * Reads a signed byte
+     *
+     * @return int Value is in the range of -128 to 127.
+     */
+    public function readByte()
+    {
+        if (($this->_needle + 1) > $this->_streamLength) {
+            require_once 'Zend/Amf/Exception.php';
+            throw new Zend_Amf_Exception('Buffer underrun at needle position: ' . $this->_needle . ' while requesting length: ' . $length);
+        }
+
+        return ord($this->_stream{$this->_needle++});
+    }
+
+    /**
+     * Writes the passed string into a signed byte on the stream.
+     *
+     * @param  string $stream
+     * @return Zend_Amf_Util_BinaryStream
+     */
+    public function writeByte($stream)
+    {
+        $this->_stream.= pack('c', $stream);
+        return $this;
+    }
+
+    /**
+     * Reads a signed 32-bit integer from the data stream.
+     *
+     * @return int Value is in the range of -2147483648 to 2147483647
+     */
+    public function readInt()
+    {
+        return ($this->readByte() << 8) + $this->readByte();
+    }
+
+    /**
+     * Write an the integer to the output stream as a 32 bit signed integer
+     *
+     * @param  int $stream
+     * @return Zend_Amf_Util_BinaryStream
+     */
+    public function writeInt($stream)
+    {
+        $this->_stream.= pack('n', $stream);
+        return $this;
+    }
+
+    /**
+     * Reads a UTF-8 string from the data stream
+     *
+     * @return string A UTF-8 string produced by the byte representation of characters
+     */
+    public function readUtf()
+    {
+        $length = $this->readInt();
+        return $this->readBytes($length);
+    }
+
+    /**
+     * Wite a UTF-8 string to the outputstream
+     *
+     * @param  string $stream
+     * @return Zend_Amf_Util_BinaryStream
+     */
+    public function writeUtf($stream)
+    {
+        $this->writeInt(strlen($stream));
+        $this->_stream.= $stream;
+        return $this;
+    }
+
+
+    /**
+     * Read a long UTF string
+     *
+     * @return string
+     */
+    public function readLongUtf()
+    {
+        $length = $this->readLong();
+        return $this->readBytes($length);
+    }
+
+    /**
+     * Write a long UTF string to the buffer
+     *
+     * @param  string $stream
+     * @return Zend_Amf_Util_BinaryStream
+     */
+    public function writeLongUtf($stream)
+    {
+        $this->writeLong(strlen($stream));
+        $this->_stream.= $stream;
+    }
+
+    /**
+     * Read a long numeric value
+     *
+     * @return double
+     */
+    public function readLong()
+    {
+        return ($this->readByte() << 24) + ($this->readByte() << 16) + ($this->readByte() << 8) + $this->readByte();
+    }
+
+    /**
+     * Write long numeric value to output stream
+     *
+     * @param  int|string $stream
+     * @return Zend_Amf_Util_BinaryStream
+     */
+    public function writeLong($stream)
+    {
+        $this->_stream.= pack('N', $stream);
+        return $this;
+    }
+
+    /**
+     * Read a 16 bit unsigned short.
+     *
+     * @todo   This could use the unpack() w/ S,n, or v
+     * @return double
+     */
+    public function readUnsignedShort()
+    {
+        $byte1 = $this->readByte();
+        $byte2 = $this->readByte();
+        return (($byte1 << 8) | $byte2);
+    }
+
+    /**
+     * Reads an IEEE 754 double-precision floating point number from the data stream.
+     *
+     * @return double Floating point number
+     */
+    public function readDouble()
+    {
+        $bytes = substr($this->_stream, $this->_needle, 8);
+        $this->_needle+= 8;
+
+        if (!$this->_bigEndian) {
+            $bytes = strrev($bytes);
+        }
+
+        $double = unpack('dflt', $bytes);
+        return $double['flt'];
+    }
+
+    /**
+     * Writes an IEEE 754 double-precision floating point number from the data stream.
+     *
+     * @param  string|double $stream
+     * @return Zend_Amf_Util_BinaryStream
+     */
+    public function writeDouble($stream)
+    {
+        $stream = pack('d', $stream);
+        if (!$this->_bigEndian) {
+            $stream = strrev($stream);
+        }
+        $this->_stream.= $stream;
+        return $this;
+    }
+
+}