Packet that contains data sent by a signal. The data can be either explicit, or implicit. More...

Inheritance diagram for IDataPacket:

Collaboration diagram for IDataPacket:

Detailed Description

Packet that contains data sent by a signal. The data can be either explicit, or implicit.

Explicit data is contained within a signal's buffer, accessible through getRawData, while implicit packets do not carry any data. Their values are calculated given a rule, packet offset, and the index of a sample within the data buffer.

To obtain implicitly calculated, or scaled values, getData should be used. The data descriptor and sample count provide information about the type and amount of data available at the obtained address.

Public Member Functions
virtual ErrCode INTERFACE_FUNC	getDataDescriptor (IDataDescriptor **descriptor)=0
	Gets the signal descriptor of the signal that sent the packet at the time of sending. More...

virtual ErrCode INTERFACE_FUNC	getSampleCount (SizeT *sampleCount)=0
	Gets the number of samples in the packet. More...

virtual ErrCode INTERFACE_FUNC	getOffset (INumber **offset)=0
	Gets current packet offset. This offset is later applied to the data rule used by a signal to calculate actual data value. This value is usually a time or other domain value. Packet offset is particularly useful when one wants to transfer a gap in otherwise equidistant samples. If we have a linear data rule, defined by equation f(x) = k*x + n, then the data value will be calculated by the equation g(x) = offset + f(x). More...

virtual ErrCode INTERFACE_FUNC	getData (void **address)=0
	Gets the calculated/scaled data address of the packet. More...

virtual ErrCode INTERFACE_FUNC	getRawData (void **address)=0
	Gets a pointer to the raw packet data. `nullptr` if the signal's data rule is implicit. More...

virtual ErrCode INTERFACE_FUNC	getDataSize (SizeT *dataSize)=0
	Gets size of data buffer in bytes. More...

virtual ErrCode INTERFACE_FUNC	getRawDataSize (SizeT *rawDataSize)=0
	Gets size of raw data buffer in bytes. More...

virtual ErrCode INTERFACE_FUNC	getDomainPacket (IDataPacket **packet)=0
	Gets the associated domain Data packet. More...

virtual ErrCode INTERFACE_FUNC	getPacketId (Int *packetId)=0
	Gets the unique packet id. More...

virtual ErrCode INTERFACE_FUNC	getLastValue (IBaseObject *value, ITypeManager typeManager=nullptr)=0
	Gets the data packet last value. More...

virtual ErrCode INTERFACE_FUNC	getValueByIndex (IBaseObject *value, SizeT index, ITypeManager typeManager=nullptr)=0
	Gets the data packet last value. More...

Public Member Functions inherited from IPacket
virtual ErrCode INTERFACE_FUNC	getType (PacketType *type)=0
	Gets the packet's type. More...

virtual ErrCode INTERFACE_FUNC	subscribeForDestructNotification (IPacketDestructCallback *packetDestructCallback)=0
	Subscribes for notification when the packet is destroyed. More...

virtual ErrCode INTERFACE_FUNC	getRefCount (SizeT *refCount)=0
	Gets the reference count of the packet. More...

Public Member Functions inherited from IBaseObject
virtual ErrCode INTERFACE_FUNC	borrowInterface (const IntfID &intfID, void **obj) const =0
	Returns another interface which is supported by the object without incrementing the reference count. More...

virtual ErrCode INTERFACE_FUNC	dispose ()=0
	Disposes all references held by the object. More...

virtual ErrCode INTERFACE_FUNC	getHashCode (SizeT *hashCode)=0
	Returns hash code of the object. More...

virtual ErrCode INTERFACE_FUNC	equals (IBaseObject other, Bool equal) const =0
	Compares object to another object for equality. More...

virtual ErrCode INTERFACE_FUNC	toString (CharPtr *str)=0
	Returns a string representation of the object. More...

Public Member Functions inherited from IUnknown
virtual ErrCode INTERFACE_FUNC	queryInterface (const IntfID &intfID, void **obj)=0
	Returns another interface which is supported by the object and increments the reference count. More...

virtual int INTERFACE_FUNC	addRef ()=0
	Increments the reference count for an interface on an object. More...

virtual int INTERFACE_FUNC	releaseRef ()=0
	Decrements the reference count for an interface on an object. More...

Member Function Documentation

◆ getData()

virtual ErrCode INTERFACE_FUNC getData ( void ** address )

pure virtual

Gets the calculated/scaled data address of the packet.

Parameters

[out] address The address of the data.

getData uses the packet's data descriptor to calculate the values as follows:

If the data rule is implicit, it uses the packet offset and sample count to calculate the data according to the rule.
If the data rule is explicit:
- If the data is a Struct, it returns a pointer to the raw data.
- If no Post scaling is defined, it simply returns a pointer to the raw data.
- If the Post scaling is defined, it scales the data and returns a pointer to the scaled data.

The data should be cast to the appropriate type, as defined by the data descriptor, and read while keeping the data dimensions in mind.

◆ getDataDescriptor()

virtual ErrCode INTERFACE_FUNC getDataDescriptor ( IDataDescriptor ** descriptor )

pure virtual

Gets the signal descriptor of the signal that sent the packet at the time of sending.

Parameters

[out] descriptor The signal descriptor.

◆ getDataSize()

virtual ErrCode INTERFACE_FUNC getDataSize ( SizeT * dataSize )

pure virtual

Gets size of data buffer in bytes.

Parameters

[out] dataSize the size of data buffer in bytes.

◆ getDomainPacket()

virtual ErrCode INTERFACE_FUNC getDomainPacket ( IDataPacket ** packet )

pure virtual

Gets the associated domain Data packet.

Parameters

[out] packet The domain data packet.

◆ getLastValue()

virtual ErrCode INTERFACE_FUNC getLastValue	(	IBaseObject **	value,
		ITypeManager *	typeManager = `nullptr`
	)

pure virtual

Gets the data packet last value.

Parameters

[out]	value	The IBaseObject value can be a nullptr if there is no value, or if the data type is not supported by the function.
	typeManager	Optional ITypeManager value can be provided to enable getLastValue for IStruct.

If a value is assigned, it can be cast based on the signal description to IFloat if the type is Float32 or Float64, to IInteger if the type is Int8 through Int64 or UInt8 through UInt64, to IComplexNumber if the type is ComplexFloat32 or ComplexFloat64, to IRange if the type is RangeInt64, to IStruct if the type is Struct, and to IList of the forementioned types if there is exactly one dimension.

◆ getOffset()

virtual ErrCode INTERFACE_FUNC getOffset ( INumber ** offset )

pure virtual

Gets current packet offset. This offset is later applied to the data rule used by a signal to calculate actual data value. This value is usually a time or other domain value. Packet offset is particularly useful when one wants to transfer a gap in otherwise equidistant samples. If we have a linear data rule, defined by equation f(x) = k*x + n, then the data value will be calculated by the equation g(x) = offset + f(x).

Parameters

[out] offset The packet offset

◆ getPacketId()

virtual ErrCode INTERFACE_FUNC getPacketId ( Int * packetId )

pure virtual

Gets the unique packet id.

Parameters

[out] packetId The packet unique id.

The packet id is automatically created on packet construction.

◆ getRawData()

virtual ErrCode INTERFACE_FUNC getRawData ( void ** address )

pure virtual

Gets a pointer to the raw packet data. nullptr if the signal's data rule is implicit.

Parameters

[out] address Pointer to the raw packet data.

◆ getRawDataSize()

virtual ErrCode INTERFACE_FUNC getRawDataSize ( SizeT * rawDataSize )

pure virtual

Gets size of raw data buffer in bytes.

Parameters

[out] dataSize the size of raw data buffer in bytes.

Raw data size is 0 if signal's data rule is implicit.

◆ getSampleCount()

virtual ErrCode INTERFACE_FUNC getSampleCount ( SizeT * sampleCount )

pure virtual

Gets the number of samples in the packet.

Parameters

[out] sampleCount the number of samples.

◆ getValueByIndex()

virtual ErrCode INTERFACE_FUNC getValueByIndex	(	IBaseObject **	value,
		SizeT	index,
		ITypeManager *	typeManager = `nullptr`
	)

pure virtual

Gets the data packet last value.

Parameters

[out]	value	The IBaseObject value can be a nullptr if there is no value, or if the data type is not supported by the function.
[in]	index	Index of the sample to obtain.
	typeManager	Optional ITypeManager value can be provided to enable getLastValue for IStruct.

If a value is assigned, it can be cast based on the signal description to IFloat if the type is Float32 or Float64, to IInteger if the type is Int8 through Int64 or UInt8 through UInt64, to IComplexNumber if the type is ComplexFloat32 or ComplexFloat64, to IRange if the type is RangeInt64, to IStruct if the type is Struct, and to IList of the forementioned types if there is exactly one dimension.

	openDAQ Open data acquisition platform

Detailed Description

Public Member Functions

Member Function Documentation

◆ getData()

◆ getDataDescriptor()

◆ getDataSize()

◆ getDomainPacket()

◆ getLastValue()

◆ getOffset()

◆ getPacketId()

◆ getRawData()

◆ getRawDataSize()

◆ getSampleCount()

◆ getValueByIndex()