PHP 5.4.31 Released

EventListener::__construct

(PECL event >= 1.2.6-beta)

EventListener::__constructCreates new connection listener associated with an event base

Description

public EventListener::__construct ( EventBase $base , callable $cb , mixed $data , int $flags , int $backlog , mixed $target )

Creates new connection listener associated with an event base.

Parameters

base

Associated event base.

cb

A callable that will be invoked when new connection received.

data

Custom user data attached to cb .

flags

Bit mask of EventListener::OPT_* constants. See EventListener constants .

backlog

Controls the maximum number of pending connections that the network stack should allow to wait in a not-yet-accepted state at any time; see documentation for your system’s listen function for more details. If backlog is negative, Libevent tries to pick a good value for the backlog ; if it is zero, Event assumes that listen is already called on the socket( target )

target

May be string, socket resource, or a stream associated with a socket. In case if target is a string, the string will be parsed as network address. It will be interpreted as a UNIX domain socket path, if prefixed with 'unix:' , e.g. 'unix:/tmp/my.sock' .

Return Values

Returns EventListener object representing the event connection listener.

Changelog

Version Description
1.5.0 UNIX domain sockets' support added.

Examples

Example #1 EventListener::__construct() example

<?php
/*
 * Simple echo server based on libevent's connection listener.
 *
 * Usage:
 * 1) In one terminal window run:
 *
 * $ php listener.php 9881
 *
 * 2) In another terminal window open up connection, e.g.:
 *
 * $ nc 127.0.0.1 9881
 *
 * 3) start typing. The server should repeat the input.
 */

class MyListenerConnection {
    private 
$bev$base;

    public function 
__destruct() {
        
$this->bev->free();
    }

    public function 
__construct($base$fd) {
        
$this->base $base;

        
$this->bev = new EventBufferEvent($base$fdEventBufferEvent::OPT_CLOSE_ON_FREE);

        
$this->bev->setCallbacks(array($this"echoReadCallback"), NULL,
            array(
$this"echoEventCallback"), NULL);

        if (!
$this->bev->enable(Event::READ)) {
            echo 
"Failed to enable READ\n";
            return;
        }
    }

    public function 
echoReadCallback($bev$ctx) {
        
// Copy all the data from the input buffer to the output buffer
        
        // Variant #1
        
$bev->output->addBuffer($bev->input);

        
/* Variant #2 */
        /*
        $input    = $bev->getInput();
        $output = $bev->getOutput();
        $output->addBuffer($input);
        */
    
}

    public function 
echoEventCallback($bev$events$ctx) {
        if (
$events EventBufferEvent::ERROR) {
            echo 
"Error from bufferevent\n";
        }

        if (
$events & (EventBufferEvent::EOF EventBufferEvent::ERROR)) {
            
//$bev->free();
            
$this->__destruct();
        }
    }
}

class 
MyListener {
    public 
$base,
        
$listener,
        
$socket;
    private 
$conn = array();

    public function 
__destruct() {
        foreach (
$this->conn as &$c$c NULL;
    }

    public function 
__construct($port) {
        
$this->base = new EventBase();
        if (!
$this->base) {
            echo 
"Couldn't open event base";
            exit(
1);
        }

        
// Variant #1
        /*
        $this->socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
        if (!socket_bind($this->socket, '0.0.0.0', $port)) {
            echo "Unable to bind socket\n";
            exit(1);
        }
        $this->listener = new EventListener($this->base,
            array($this, "acceptConnCallback"), $this->base,
            EventListener::OPT_CLOSE_ON_FREE | EventListener::OPT_REUSEABLE,
            -1, $this->socket);
         */

        // Variant #2
         
$this->listener = new EventListener($this->base,
             array(
$this"acceptConnCallback"), $this->base,
             
EventListener::OPT_CLOSE_ON_FREE EventListener::OPT_REUSEABLE, -1,
             
"0.0.0.0:$port");

        if (!
$this->listener) {
            echo 
"Couldn't create listener";
            exit(
1);
        }

        
$this->listener->setErrorCallback(array($this"accept_error_cb"));
    }

    public function 
dispatch() {
        
$this->base->dispatch();
    }

    
// This callback is invoked when there is data to read on $bev
    
public function acceptConnCallback($listener$fd$address$ctx) {
        
// We got a new connection! Set up a bufferevent for it. */
        
$base $this->base;
        
$this->conn[] = new MyListenerConnection($base$fd);
    }

    public function 
accept_error_cb($listener$ctx) {
        
$base $this->base;

        
fprintf(STDERR"Got an error %d (%s) on the listener. "
            
."Shutting down.\n",
            
EventUtil::getLastSocketErrno(),
            
EventUtil::getLastSocketError());

        
$base->exit(NULL);
    }
}

$port 9808;

if (
$argc 1) {
    
$port = (int) $argv[1];
}
if (
$port <= || $port 65535) {
    exit(
"Invalid port");
}

$l = new MyListener($port);
$l->dispatch();
?>
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