Event Handler for Mcast messages. NOT THREAD-SAFE. More...

#include <ECG_Mcast_EH.h>

Inheritance diagram for TAO_ECG_Mcast_EH:

Collaboration diagram for TAO_ECG_Mcast_EH:

Classes
class	Observer
	Observes changes in the EC consumer subscriptions and notifies TAO_ECG_Mcast_EH when there are changes. More...
class	Observer_Disconnect_Command
	Disconnects Observer from the Event Channel. More...
struct	Subscription
Public Member Functions
virtual int	handle_input (ACE_HANDLE fd)

	TAO_ECG_Mcast_EH (TAO_ECG_Dgram_Handler recv, const ACE_TCHAR net_if=0, CORBA::ULong buf_sz=0)
	Initialization and termination methods.
virtual	~TAO_ECG_Mcast_EH (void)
	Destructor.
void	open (RtecEventChannelAdmin::EventChannel_ptr ec)
virtual int	shutdown (void)
	TAO_ECG_Handler_Shutdown method.
Private Types
typedef ACE_Unbounded_Set < ACE_INET_Addr >	Address_Set
typedef ACE_Array_Base < Subscription >	Subscriptions
Private Member Functions
void	update_consumer (const RtecEventChannelAdmin::ConsumerQOS &sub)

void	compute_required_subscriptions (const RtecEventChannelAdmin::ConsumerQOS &sub, Address_Set &multicast_addresses)
int	delete_unwanted_subscriptions (Address_Set &multicast_addresses)
void	add_new_subscriptions (Address_Set &multicast_addresses)
Private Attributes
ACE_TCHAR *	net_if_
	The NIC used to subscribe for multicast traffic.
Subscriptions	subscriptions_
	List of multicast addresses we subscribe to and dgrams we use.
TAO_ECG_Dgram_Handler *	receiver_
	We callback to this object when a message arrives.
CORBA::ULong	recvbuf_size_
	SOCKbuf size.
PortableServer::Servant_var < Observer >	observer_
TAO_EC_Auto_Command < Observer_Disconnect_Command >	auto_observer_disconnect_
Friends
class	Observer
	Make update_consumer () accessible to Observer.

Detailed Description

Event Handler for Mcast messages. NOT THREAD-SAFE.

This object acts as an Observer to Event Channel. It subscribes to multicast groups that carry events matching the EC's subscriptions. This object then receives callbacks from the Reactor when data is available on the mcast sockets and alerts TAO_ECG_Dgram_Handler, which reads the data, transforms it into event and pushes to the Event Channel.

Member Typedef Documentation

typedef ACE_Unbounded_Set<ACE_INET_Addr> TAO_ECG_Mcast_EH::Address_Set [private]

typedef ACE_Array_Base<Subscription> TAO_ECG_Mcast_EH::Subscriptions [private]

Constructor & Destructor Documentation

TAO_ECG_Mcast_EH::TAO_ECG_Mcast_EH	(	TAO_ECG_Dgram_Handler *	recv,
		const ACE_TCHAR *	net_if = `0`,
		CORBA::ULong	buf_sz = `0`
	)

Initialization and termination methods.

Constructor. Messages received by this EH will be forwarded to the recv. net_if can be used to specify NIC where multicast messages are expected. would be used to alter the default buffer size.

See comments for receiver_ data member on why raw pointer is used for the recv argument.

TAO_ECG_Mcast_EH::~TAO_ECG_Mcast_EH ( void ) [virtual]

Destructor.

Member Function Documentation

void TAO_ECG_Mcast_EH::add_new_subscriptions ( Address_Set & multicast_addresses ) [private]

Subscribe to all multicast addresses in /a multicast_addresses - we are not subscribed to them yet, but need to be.

Parameters:

multicast_addresses List of multicast addresses to which we need to subscribe to in order to be receiving all event types in the current consumer subscriptions.

void TAO_ECG_Mcast_EH::compute_required_subscriptions	(	const RtecEventChannelAdmin::ConsumerQOS &	sub,
		Address_Set &	multicast_addresses
	)		`[private]`

Helpers for updating multicast subscriptions based on changes in consumer subscriptions. Compute the list of multicast addresses that we need to be subscribed to, in order to receive the events described in the ConsumerQOS parameter.

Parameters:

sub	The list of event types that our event channel consumers are interested in.
multicast_addresses	This method populates this list with multicast addresses that we need to be subscribed to in order to receive event types specified in /a sub.

Exceptions:

CORBA::SystemException This method needs to perform several CORBA invocations, and it propagates any exceptions back to the caller.

int TAO_ECG_Mcast_EH::delete_unwanted_subscriptions ( Address_Set & multicast_addresses ) [private]

Unsubscribe from any multicast addresses we are currently subscribed to that are not in the multicast_addresses list. Also remove from /a multicast_addresses any addresses to which we are already subscribed.

Parameters:

multicast_addresses List of multicast addresses we need to be subscribed to in order receive all event types in the current consumer subscriptions.

int TAO_ECG_Mcast_EH::handle_input ( ACE_HANDLE fd ) [virtual]

Reactor callback. Notify receiver_ that a dgram corresponding to fd is ready for reading.

Reimplemented from ACE_Event_Handler.

void TAO_ECG_Mcast_EH::open ( RtecEventChannelAdmin::EventChannel_ptr ec )

Register for changes in the EC subscription list. When the subscription list becomes non-empty we join the proper multicast groups (using Dgram_Handler to translate between event types and mcast groups) and the class registers itself with the reactor.

To insure proper resource clean up, if open () is successful, the user MUST call shutdown () when handler is no longer needed (and its reactor still exists).

int TAO_ECG_Mcast_EH::shutdown ( void ) [virtual]

TAO_ECG_Handler_Shutdown method.

Remove ourselves from the event channel, unsubscribe from the multicast groups, close the sockets and deregister from the reactor.

Implements TAO_ECG_Handler_Shutdown.

void TAO_ECG_Mcast_EH::update_consumer ( const RtecEventChannelAdmin::ConsumerQOS & sub ) [private]

The Observer method. Subscribe/unsubscribe to multicast groups according to changes in consumer subscriptions.

Friends And Related Function Documentation

friend class Observer [friend]

Make update_consumer () accessible to Observer.

Member Data Documentation

TAO_EC_Auto_Command<Observer_Disconnect_Command> TAO_ECG_Mcast_EH::auto_observer_disconnect_ [private]

Manages connection of our observer to the Event Channel. ORDER DEPENDENCY: this member should be declared AFTER <observer_>.

ACE_TCHAR* TAO_ECG_Mcast_EH::net_if_ [private]

The NIC used to subscribe for multicast traffic.

PortableServer::Servant_var<Observer> TAO_ECG_Mcast_EH::observer_ [private]

Event Channel Observer. Detects changes in EC consumer subscriptions. ORDER DEPENDENCY: this member should be declared before <auto_observer_disconnect_>.

TAO_ECG_Dgram_Handler* TAO_ECG_Mcast_EH::receiver_ [private]

We callback to this object when a message arrives.

CORBA::ULong TAO_ECG_Mcast_EH::recvbuf_size_ [private]

SOCKbuf size.

Subscriptions TAO_ECG_Mcast_EH::subscriptions_ [private]

List of multicast addresses we subscribe to and dgrams we use.

The documentation for this class was generated from the following files: