Client not handling broken connections while in read loop

[ejsmont-artur]

Hi there

I have just noticed today that process gets stuck in read/poll loop if connection gets dropped or server dies.

This code does not seem to recognise that socket has been closed

$read = fread($this->_socket, $rb);

        if ($read === false) {
            $this->_reconnect();
            return $this->readFrame();
        }

I dont have patch for now as i could not find a way to check if file handler is still readable.

In case of server dying im getting back string "" from fread not FALSE. It was tested on php 5.3

Thanks

Art

[marklr]

This is an issue with PHP's wrapping of the actual C function, I think that the space check would be added along with !== false.

[ejsmont-artur]

well i have not got time to test it but if there was a way to distinguish between lost connection and no data then it would be all good. Do you think would feof work?

http://www.php.net/manual/en/function.feof.php

[marklr]

Wouldn't hurt to see whether checking for false and empty string does the job. Otherwise, we could use stream_get_meta_data and check for 'unread_bytes', etc.

[ejsmont-artur]

Well, maybe, I thought on read timeout you will get empty string as well but maybe it would be a null? :)

I wanted to set read timeout to some 10s and also have outer loop with a check if i exceeded count of messages or time to live and end process to garbage collect it. PHP was never fully reliable as an infinite-loop tool, but mabe nowadays its ok and im just too cautious :)

[lirenzhu]

The issue here is with hasFrameRead method. As a direct result of the first if statement ($has_frame_to_read !== false), it will always consider a timed out connection as "having a frame to read," so to speak.

[bathizte]

Testing feof inside hasFrameToRead resolves the issue :

if(feof($this->_socket)){
    require_once 'Stomp/Exception.php';
    throw new StompException('Disconnected');
}