I have create a multiple clients socket connection. Its working fine, but once if i remove the cable from one of the client it still shows a established connection. Is there any way to close the Half-Open (Dropped) TCP/IP Socket Connections in php.
Below is the code to create the multiple client connection socket server :
<?php
/*! @class SocketServer
@author Navarr Barnier
@abstract A Framework for creating a multi-client server using the PHP language.
*/
class SocketServer
{
/*! @var config
@abstract Array - an array of configuration information used by the server.
*/
protected $config;
/*! @var hooks
@abstract Array - a dictionary of hooks and the callbacks attached to them.
*/
protected $hooks;
/*! @var master_socket
@abstract resource - The master socket used by the server.
*/
protected $master_socket;
/*! @var max_clients
@abstract unsigned int - The maximum number of clients allowed to connect.
*/
public $max_clients = 1000;
/*! @var max_read
@abstract unsigned int - The maximum number of bytes to read from a socket at a single time.
*/
public $max_read = 1460;
/*! @var clients
@abstract Array - an array of connected clients.
*/
public $clients;
/*! @function __construct
@abstract Creates the socket and starts listening to it.
@param string - IP Address to bind to, NULL for default.
@param int - Port to bind to
@result void
*/
public function __construct($bind_ip,$port)
{
//sudo lsof -n -i :3490 | grep LISTEN
set_time_limit(0);
$this->hooks = array();
$this->config["ip"] = $bind_ip;
$this->config["port"] = $port;
$this->master_socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_bind($this->master_socket,$this->config["ip"],$this->config["port"]) or die("Issue Binding");
socket_getsockname($this->master_socket,$bind_ip,$port);
socket_listen($this->master_socket);
SocketServer::debug("Listenting for connections on {$bind_ip}:{$port}");
}
/*! @function hook
@abstract Adds a function to be called whenever a certain action happens. Can be extended in your implementation.
@param string - Command
@param callback- Function to Call.
@see unhook
@see trigger_hooks
@result void
*/
public function hook($command,$function)
{
$command = strtoupper($command);
if(!isset($this->hooks[$command])) { $this->hooks[$command] = array(); }
$k = array_search($function,$this->hooks[$command]);
if($k === FALSE)
{
$this->hooks[$command][] = $function;
}
}
/*! @function unhook
@abstract Deletes a function from the call list for a certain action. Can be extended in your implementation.
@param string - Command
@param callback- Function to Delete from Call List
@see hook
@see trigger_hooks
@result void
*/
public function unhook($command = NULL,$function)
{
$command = strtoupper($command);
if($command !== NULL)
{
$k = array_search($function,$this->hooks[$command]);
if($k !== FALSE)
{
unset($this->hooks[$command][$k]);
}
} else {
$k = array_search($this->user_funcs,$function);
if($k !== FALSE)
{
unset($this->user_funcs[$k]);
}
}
}
/*! @function loop_once
@abstract Runs the class's actions once.
@discussion Should only be used if you want to run additional checks during server operation. Otherwise, use infinite_loop()
@param void
@see infinite_loop
@result bool - True
*/
public function loop_once()
{
// Setup Clients Listen Socket For Reading
$read =array();
$write = array();
$except = array();
$read[0] = $this->master_socket;
for($i = 0; $i < $this->max_clients; $i++)
{
if(isset($this->clients[$i]))
{
$read[$i + 1] = $this->clients[$i]->socket;
}
}
// Set up a blocking call to socket_select
if(socket_select($read,$write, $except, $tv_sec = 5) < 1)
{
//SocketServer::debug("Problem blocking socket_select?");
return true;
}
// Handle new Connections
if(in_array($this->master_socket, $read))
{
for($i = 0; $i < $this->max_clients; $i++)
{
if(empty($this->clients[$i]))
{
$temp_sock = $this->master_socket;
$this->clients[$i] = new SocketServerClient($this->master_socket,$i);
$this->trigger_hooks("CONNECT",$this->clients[$i],"");
break;
}
elseif($i == ($this->max_clients-1))
{
SocketServer::debug("Too many clients... :( ");
}
}
}
// Handle Input
for($i = 0; $i < $this->max_clients; $i++) // for each client
{
if(isset($this->clients[$i]))
{
//SocketServer::debug(implode('||',$read).' --> check 1 '.$this->clients[$i]->socket);
if(in_array($this->clients[$i]->socket, $read))
{
$input = socket_read($this->clients[$i]->socket, $this->max_read);
SocketServer::debug($this->clients[$i]->socket.' --> '.$input);
if($input == null || $input == 0 || $input == '')
{
$this->disconnect($i);
}
else
{
//$this->socket_write_smart($this->clients[$i]->socket,$input,"");
//SocketServer::debug("{$i}@{$this->clients[$i]->ip} --> {$input}");
$this->writeDataIntoDB($input);
$this->trigger_hooks("INPUT",$this->clients[$i],$input);
}
}
}
}
return true;
}
public function writeDataIntoDB($input)
{
$gateway = new GatewayWebservice();
$gateway->storeSocketGatewayData($input);
$gateway->checkData($input);
/*$file = time();
$fp = fopen('data/testdata.txt', 'a+');
fwrite($fp, $input);
fclose($fp);*/
}
/*! @function disconnect
@abstract Disconnects a client from the server.
@param int - Index of the client to disconnect.
@param string - Message to send to the hooks
@result void
*/
public function disconnect($client_index,$message = "")
{
$i = $client_index;
SocketServer::debug("Client {$i} from {$this->clients[$i]->ip} Disconnecting");
$this->trigger_hooks("DISCONNECT",$this->clients[$i],$message);
$this->clients[$i]->destroy();
unset($this->clients[$i]);
}
/*! @function trigger_hooks
@abstract Triggers Hooks for a certain command.
@param string - Command who's hooks you want to trigger.
@param object - The client who activated this command.
@param string - The input from the client, or a message to be sent to the hooks.
@result void
*/
public function trigger_hooks($command,&$client,$input)
{
if(isset($this->hooks[$command]))
{
foreach($this->hooks[$command] as $function)
{
SocketServer::debug("Triggering Hook '{$function}' for '{$command}'");
//$continue = call_user_func($function,&$this,&$client,$input);
$continue = call_user_func_array($function, array(&$this,&$client,$input));
if($continue === FALSE) { break; }
}
}
}
/*! @function infinite_loop
@abstract Runs the server code until the server is shut down.
@see loop_once
@param void
@result void
*/
public function infinite_loop()
{
$test = true;
do
{
$test = $this->loop_once();
}
while($test);
}
/*! @function debug
@static
@abstract Outputs Text directly.
@discussion Yeah, should probably make a way to turn this off.
@param string - Text to Output
@result void
*/
public static function debug($text)
{
echo("{$text}\r\n");
}
/*! @function socket_write_smart
@static
@abstract Writes data to the socket, including the length of the data, and ends it with a CRLF unless specified.
@discussion It is perfectly valid for socket_write_smart to return zero which means no bytes have been written. Be sure to use the === operator to check for FALSE in case of an error.
@param resource- Socket Instance
@param string - Data to write to the socket.
@param string - Data to end the line with. Specify a "" if you don't want a line end sent.
@result mixed - Returns the number of bytes successfully written to the socket or FALSE on failure. The error code can be retrieved with socket_last_error(). This code may be passed to socket_strerror() to get a textual explanation of the error.
*/
public static function socket_write_smart(&$sock,$string,$crlf = "\r\n")
{
SocketServer::debug("<-- {$string}");
if($crlf) { $string = "{$string}{$crlf}"; }
return socket_write($sock,$string,strlen($string));
}
/*! @function __get
@abstract Magic Method used for allowing the reading of protected variables.
@discussion You never need to use this method, simply calling $server->variable works because of this method's existence.
@param string - Variable to retrieve
@result mixed - Returns the reference to the variable called.
*/
function &__get($name)
{
return $this->{$name};
}
}
/*! @class SocketServerClient
@author Navarr Barnier
@abstract A Client Instance for use with SocketServer
*/
class SocketServerClient
{
/*! @var socket
@abstract resource - The client's socket resource, for sending and receiving data with.
*/
protected $socket;
/*! @var ip
@abstract string - The client's IP address, as seen by the server.
*/
protected $ip;
/*! @var hostname
@abstract string - The client's hostname, as seen by the server.
@discussion This variable is only set after calling lookup_hostname, as hostname lookups can take up a decent amount of time.
@see lookup_hostname
*/
protected $hostname;
/*! @var server_clients_index
@abstract int - The index of this client in the SocketServer's client array.
*/
protected $server_clients_index;
/*! @function __construct
@param resource- The resource of the socket the client is connecting by, generally the master socket.
@param int - The Index in the Server's client array.
@result void
*/
public function __construct(&$socket,$i)
{
$this->server_clients_index = $i;
$this->socket = socket_accept($socket) or die("Failed to Accept");
socket_getpeername($this->socket,$ip);
SocketServer::debug("New Client ".$i." Connected -> IP:".$ip);
$this->ip = $ip;
}
/*! @function lookup_hostname
@abstract Searches for the user's hostname and stores the result to hostname.
@see hostname
@param void
@result string - The hostname on success or the IP address on failure.
*/
public function lookup_hostname()
{
$this->hostname = gethostbyaddr($this->ip);
return $this->hostname;
}
/*! @function destroy
@abstract Closes the socket. Thats pretty much it.
@param void
@result void
*/
public function destroy()
{
socket_close($this->socket);
}
function &__get($name)
{
return $this->{$name};
}
function __isset($name)
{
return isset($this->{$name});
}
}
