Drv::Udp UDP Component

The UDP client component bridges the byte stream driver model interface to a remote UDP port to which this udp component sends/receives bytes. It implements the callback formation (shown below) using a thread to receive data and producing the callback port call. Udp does not require bidirectional operation and can be used in a single direction.

For more information on the supporting UDP implementation see: Drv::UdpSocket. For more information on the ByteStreamModelDriver see: Drv::ByteStreamDriverModel.

Design

The TcpClient component implements the design specified by the Drv::ByteStreamDriverModel.

Usage

The Drv::UdpComponentImpl must be configured with the address(es) of the remote entity. Users can configure send and receive independently using configureSend and configureRecv. The sockets must also be opened to send and receive data using the open call. When the component is set to automatically open, open is called via the first send or receive call. Users declining to use automatic opening or who wish to control when open initially happens should call open before sending or receiving.

Automatic opening is the default. Call setAutomaticOpen(false); to disable this behavior.

Users desiring to receive via UDP should start the receive thread using start, may stop the thread using stop and may wait for the thread to exit using join.

Since UDP support single or bidirectional communication, configuring each direction is done separately using the two methods configureSend and configureRecv. The user must call at least one of the configure methods and may call both.

Ephemeral Port Support

The Drv::UdpComponentImpl supports ephemeral ports for receiving data. This is done by setting the port number to 0 when calling configureRecv. The port number will be returned when the socket is opened.

When configured as a receiver-only the Drv::UdpComponentImpl can also be set up to send a response back to the sender and use the response port that the sender has indicated in the UDP datagram. This is done by setting the port number to 0 when calling configureSend.

Drv::UdpComponentImpl comm = Drv::UdpComponentImpl("UDP Client");

bool constructApp(bool dump, U32 port_number, char* hostname) {
    ...
    comm.configureSend(hostname, port_number);
    comm.configureRecv(hostname, port_number);
    ...
    if (hostname != nullptr && port_number != 0) {
        Os::TaskString name("ReceiveTask");
        // Needed for receiving only, remove if not configuring to receive
        comm.startSocketTask(name);
    }
}

void exitTasks() {
    ...
    comm.stop();
    (void) comm.join();
}

Requirements

Name	Description	Validation
UDP-COMP-001	The udp component shall implement the ByteStreamDriverModel	inspection
UDP-COMP-002	The udp component shall provide a read thread	unit test
UDP-COMP-003	The udp component shall provide single and bidirectional communication across udp	unit test