MyUdpTransform Struct Reference

The custom UDP transformation class. More...

Data Fields
struct UDP_Transform	_parent
	Base-class. All UDP transforms must inherit from UDP_Transform.
struct MyUdpTransformFactory *	factory
	A reference to its own factory, if properties must be accessed.
NETIO_Packet_T	packet
	NETIO_Packet to hold a transformed payload.
char *	buffer
	The payload to assign to NETIO_Packet_T.
RTI_SIZE_T	max_buffer_length
	The maximum length of the buffer. NOTE: The buffer must be 1 byte larger than the largest buffer.

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Detailed Description

The custom UDP transformation class.

The MyUdpTransformFactory creates one instance of this class for each UDP interface created. In this example one packet buffer (NETIO_Packet_T), is allocated and a buffer to hold the transformed data (buffer)

Only one transformation can be done at a time and it is synchronous. Thus, it is sufficient with one buffer to transform input and output per instance of the MyUdpTransform.

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Field Documentation

struct UDP_Transform MyUdpTransform::_parent

Base-class. All UDP transforms must inherit from UDP_Transform.

Referenced by MyUdpTransform_create(), and MyUdpTransformFactory_create_component().

struct MyUdpTransformFactory* MyUdpTransform::factory

A reference to its own factory, if properties must be accessed.

Referenced by MyUdpTransform_create().

NETIO_Packet_T MyUdpTransform::packet

NETIO_Packet to hold a transformed payload.

RTI Connext DDS Micro uses a NETIO_Packet_T to abstract data payload and this is what is being passed betweem the UDP transport and the transformation. The transformation must convert a payload into a NETIO_Packet. This is done with NETIO_Packet_initialize_from. This function saves all state except the payload buffer.

char* MyUdpTransform::buffer

The payload to assign to NETIO_Packet_T.

A transformation cannot do in-place transformations because the input buffer may be sent multiple times (for example due to reliability). A transformation instance can only transform one buffer at a time (send or receive). The buffer must be large enough to hold a transformed payload. When the the transformation is created it receives a UDP_TransformProperty. This property has the max send and receive buffers for transport and can be used to sise the buffer. Please refer to UDP_InterfaceFactoryProperty::max_send_message_size and UDP_InterfaceFactoryProperty::max_message_size.

Referenced by MyUdpTransform_create(), and MyUdpTransform_delete().

RTI_SIZE_T MyUdpTransform::max_buffer_length

The maximum length of the buffer. NOTE: The buffer must be 1 byte larger than the largest buffer.

Referenced by MyUdpTransform_create().