<?php
/**
* Memory-efficient integer storage class.
* Behaves like a normal array.
*
* This one uses: BINARY STRING
* and stores: 8 BIT integer.
*
*
* For example: 32768 entries use just their 32768 bytes
* (plus 1240 byte for the object instance).
*
*
*/
class ByteArray IMPLEMENTS ArrayAccess {
var $data = "\0";
var $len = 1; // 1 byte = 8 bit
var $pack = "C";
/**
* Initialize data.
*
* @param integer/string create either a fixed size empty array,
* or use source data (hexstring)
*/
function __construct($from=NULL) {
if (is_string($from)) {
$this->data = $from;
}
elseif (is_int($from)) {
$this->data = str_repeat("\0", $this->len * $from);
}
}
/**
* Compare array index against data size.
*
*/
function offsetExists ( $offset ) {
return strlen($this->data) - 1 >= $offset;
}
/**
* Retrieve value.
*
*/
function offsetGet ( $offset ) {
return ord($this->data[$offset]);
}
/**
* Update value.
*
*/
function offsetSet ( $offset , $value ) {
# assert($value < 0x100);
$this->data[$offset] = chr($value);
}
/**
* Unsetting not supported.
*
*/
function offsetUnset ( $offset ) {
assert(false);
}
}
?>
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