Description:
------------
PHP's fread() function reads only the first 8192 bytes of any file accessed via a stream wrapper, even if the file is bigger and the wrappers' stream_eof() method returns false to signal it is NOT the end of the file.

I expect fread() to repeat calling the wrappers' stream_read()  and stream_eof() methods until stream_eof() signals the end of file or stream_read() returns less than the requested 8192 bytes.

I encountered this behaviour with PHP 5.2.0 on Win32 and Linux x86.

Reproduce code:
---------------
<?

class PHP_Bug {
	private $data; private $pos;
	function initializeStream()
	{
		$this->data = str_repeat("-",16399);
		$this->pos = 0;
	}
	function stream_open($fn)
	{
		$this->initializeStream();
		return true;
	}
	function stream_stat()
	{
		$this->initializeStream();
		return array(0,0,0100444,"mode"=>0100444,"size"=>strlen($this->data));
	}
	function url_stat()
	{
		return $this->stream_stat();
	}
	function stream_read($cnt)
	{
		echo __METHOD__."(".$cnt.")\n";
		$ret = substr($this->data,$this->pos,$cnt);
		$this->pos += strlen($ret);
		return $ret;
	}
	function stream_eof()
	{
		$ret = ($this->pos >= strlen($this->data));
		echo __METHOD__."=".(($ret)?"true":"false")."\n";
		return $ret;
	}
}

stream_wrapper_register("bug","PHP_Bug");

$fs = filesize("bug://");
$fp = fopen("bug://","r");
$ret = fread($fp,$fs);
fclose($fp);
echo "size is ".strlen($ret)."\n";

?>

Expected result:
----------------
PHP_Bug::stream_read(8192)
PHP_Bug::stream_eof=false
PHP_Bug::stream_read(8192)
PHP_Bug::stream_eof=false
PHP_Bug::stream_read(8192)
PHP_Bug::stream_eof=true
size is 16399

Actual result:
--------------
PHP_Bug::stream_read(8192)
PHP_Bug::stream_eof=false
size is 8192