--- /dev/null
+<?php
+/**
+ * Classes, which help reading streams of data from files.
+ * Based on the classes from Danilo Segan <danilo@kvota.net>
+ *
+ * @version $Id: streams.php 138 2009-06-23 13:22:09Z 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;
+ $this->is_overloaded = ((ini_get("mbstring.func_overload") & 2) != 0) && function_exists('mb_substr');
+ }
+
+ function _substr($string, $start, $length) {
+ if ($this->is_overloaded) {
+ return mb_substr($string,$start,$length,'ascii');
+ } else {
+ return substr($string,$start,$length);
+ }
+ }
+
+ function _strlen($string) {
+ if ($this->is_overloaded) {
+ return mb_strlen($string,'ascii');
+ } else {
+ return strlen($string);
+ }
+ }
+
+ function read($bytes) {
+ $data = $this->_substr($this->_str, $this->_pos, $bytes);
+ $this->_pos += $bytes;
+ if ($this->_strlen($this->_str) < $this->_pos) $this->_pos = $this->_strlen($this->_str);
+ return $data;
+ }
+
+ function seekto($pos) {
+ $this->_pos = $pos;
+ if ($this->_strlen($this->_str) < $this->_pos) $this->_pos = $this->_strlen($this->_str);
+ return $this->_pos;
+ }
+
+ function pos() {
+ return $this->_pos;
+ }
+
+ function length() {
+ return $this->_strlen($this->_str);
+ }
+
+}
+
+/**
+ * Reads the contents of the file in the beginning.
+ */
+class POMO_CachedFileReader extends POMO_StringReader {
+ function POMO_CachedFileReader($filename) {
+ parent::POMO_StringReader();
+ $this->_str = file_get_contents($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 != $this->_strlen($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 != $this->_strlen($bytes))
+ return false;
+ $endian_letter = ('big' == $this->endian)? 'N' : 'V';
+ return unpack($endian_letter.$count, $bytes);
+ }
+}
+
+?>