WordPress/wp-includes/pomo/streams.php

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<?php
/**
* Classes, which help reading streams of data from files.
* Based on the classes from Danilo Segan <danilo@kvota.net>
*
* @version $Id: streams.php 33 2009-02-16 09:33:39Z nbachiyski $
* @package pomo
* @subpackage streams
*/
/**
* Provides file-like methods for manipulating a string instead
* of a physical file.
*/
class POMO_StringReader {
var $_pos;
var $_str;
function POMO_StringReader($str = '') {
$this->_str = $str;
$this->_pos = 0;
}
function read($bytes) {
$data = substr($this->_str, $this->_pos, $bytes);
$this->_pos += $bytes;
if (strlen($this->_str)<$this->_pos)
$this->_pos = strlen($this->_str);
return $data;
}
function seekto($pos) {
$this->_pos = $pos;
if (strlen($this->_str)<$this->_pos)
$this->_pos = strlen($this->_str);
return $this->_pos;
}
function pos() {
return $this->_pos;
}
function length() {
return strlen($this->_str);
}
}
/**
* Reads the contents of the file in the beginning.
*/
class POMO_CachedFileReader extends POMO_StringReader {
function POMO_CachedFileReader($filename) {
$this->_str = file_get_contents($filename);
if (false === $this->_str)
return false;
$this->pos = 0;
}
}
/**
* Allows reading integers from a file.
*/
class POMO_CachedIntFileReader extends POMO_CachedFileReader {
var $endian = 'little';
/**
* Opens a file and caches it.
*
* @param $filename string name of the file to be opened
* @param $endian string endianness of the words in the file, allowed
* values are 'little' or 'big'. Default value is 'little'
*/
function POMO_CachedIntFileReader($filename, $endian = 'little') {
$this->endian = $endian;
parent::POMO_CachedFileReader($filename);
}
/**
* Sets the endianness of the file.
*
* @param $endian string 'big' or 'little'
*/
function setEndian($endian) {
$this->endian = $endian;
}
/**
* Reads a 32bit Integer from the Stream
*
* @return mixed The integer, corresponding to the next 32 bits from
* the stream of false if there are not enough bytes or on error
*/
function readint32() {
$bytes = $this->read(4);
if (4 != strlen($bytes))
return false;
$endian_letter = ('big' == $this->endian)? 'N' : 'V';
$int = unpack($endian_letter, $bytes);
return array_shift($int);
}
/**
* Reads an array of 32-bit Integers from the Stream
*
* @param integer count How many elements should be read
* @return mixed Array of integers or false if there isn't
* enough data or on error
*/
function readint32array($count) {
$bytes = $this->read(4 * $count);
if (4*$count != strlen($bytes))
return false;
$endian_letter = ('big' == $this->endian)? 'N' : 'V';
return unpack($endian_letter.$count, $bytes);
}
}
?>