Detailed Description

template<typename T = unsigned char>
class walberla::mpi::GenericRecvBuffer< T >

Implementation of a MPI receive buffer.

The RecvBuffer class is a special purpose implementation for the MPI communication functionality. It offers a convenient and safe access to the received data values even for mixed-type communication. The following example gives an impression of the usage of the RecvBuffer class:

using namespace mpi;
 
// Preparing a receive buffer for an incoming message of 32 bytes
RecvBuffer buffer;
buffer.resize( 32 );
 
// Receiving a MPI message from process 0 in a blocking MPI_Recv() function
MPI_Status status;
MPI_Recv( buffer.ptr(), 32, MPI_BYTE, 0, MPI_ANY_TAG, MPI_COMM_WORLD, status );
 
// Extracting a double and an integer from the buffer
double d;
int i;
buffer >> d >> i;

For another example see also the Buffer Unit Test in File BufferTest.cpp

Note that the order of data values in the receive buffer is depending on the message sent via MPI. See also the SendBuffer class description for the sender side of the MPI communication.

#include <RecvBuffer.h>

Public Types
using	ElementType = T
	Type of the receive buffer elements. More...

Public Member Functions
template<typename G >
GenericRecvBuffer< T > &	operator= (const GenericSendBuffer< T, G > &sb)

Constructors
	GenericRecvBuffer ()
	Standard constructor for RecvBuffer. More...

	GenericRecvBuffer (const GenericRecvBuffer &rb)
	Copy constructor for RecvBuffer. More...

template<typename G >
	GenericRecvBuffer (GenericSendBuffer< T, G > &sb)
	Constructor for RecvBuffer. More...

Destructor
	~GenericRecvBuffer ()
	Destructor for RecvBuffer. More...

Assignment operator
GenericRecvBuffer &	operator= (const GenericRecvBuffer &sb)
	Copy assignment operator for RecvBuffer. More...

template<typename G >
GenericRecvBuffer &	operator= (const GenericSendBuffer< T, G > &sb)

Get functions
size_t	maxSize () const
	Returns the maximum possible size of the receive buffer. More...

size_t	size () const
	Returns the current size of the receive buffer. More...

size_t	capacity () const
	Returns the capacity of the receive buffer. More...

bool	isEmpty () const
	Returns true if the receive buffer is empty. More...

Operators
template<typename V >
std::enable_if< std::is_arithmetic< V >::value\|\|std::is_enum< V >::value, GenericRecvBuffer & >::type	operator>> (V &value)
	Reads a built-in data value from the receive buffer. More...

Private Attributes
Member variables
size_t	capacity_
	The current size of the receive buffer. More...

T *	begin_
	Pointer to the first element of the receive buffer. More...

T *	cur_
	Pointer to the current element of the receive buffer. More...

T *	end_
	Pointer to the last element of the receive buffer. More...

Utility functions
T *	ptr () const
	Returns a pointer to the first element of the receive buffer. More...

void	reserve (size_t newCapacity)
	Setting the minimum capacity of the receive buffer. More...

void	resize (size_t newSize)
	Changing the size of the receive buffer. More...

template<typename V >
void	peek (V &value) const
	Reads a built-in data value from the receive buffer without extracting it. More...

T *	skip (size_t elements)
	Skipping the given number of elements. More...

void	clear ()
	Clearing the receive buffer. More...

void	reset ()
	Clearing the receive buffer. More...

void	readDebugMarker (const char *marker)
	Reads debug marker and raises assert when marker does not match. More...

template<typename V >
std::enable_if< std::is_arithmetic< V >::value\|\|std::is_enum< V >::value, GenericRecvBuffer & >::type	get (V &value)
	Implements operator>> without debugging system. More...

Member Typedef Documentation

◆ ElementType

template<typename T = unsigned char>

using walberla::mpi::GenericRecvBuffer< T >::ElementType = T

Type of the receive buffer elements.

Constructor & Destructor Documentation

◆ GenericRecvBuffer() [1/3]

template<typename T >

walberla::mpi::GenericRecvBuffer< T >::GenericRecvBuffer

inlineexplicit

Standard constructor for RecvBuffer.

◆ GenericRecvBuffer() [2/3]

template<typename T >

walberla::mpi::GenericRecvBuffer< T >::GenericRecvBuffer ( const GenericRecvBuffer< T > & rb )

inline

Copy constructor for RecvBuffer.

Parameters

rb	The receive buffer to be copied.

◆ GenericRecvBuffer() [3/3]

template<typename T >

template<typename G >

walberla::mpi::GenericRecvBuffer< T >::GenericRecvBuffer ( GenericSendBuffer< T, G > & sb )

inlineexplicit

Constructor for RecvBuffer.

Parameters

sb	The send buffer whose content is transfered to this receive buffer.

◆ ~GenericRecvBuffer()

template<typename T >

walberla::mpi::GenericRecvBuffer< T >::~GenericRecvBuffer

inline

Destructor for RecvBuffer.

Member Function Documentation

◆ capacity()

template<typename T >

size_t walberla::mpi::GenericRecvBuffer< T >::capacity

inline

Returns the capacity of the receive buffer.

Returns: The capacity.

◆ clear()

template<typename T >

void walberla::mpi::GenericRecvBuffer< T >::clear

inline

Clearing the receive buffer.

Returns: void

This function performs a complete reset of the receive buffer.

◆ get()

template<typename T >

template<typename V >

std::enable_if< std::is_arithmetic< V >::value||std::is_enum< V >::value, GenericRecvBuffer< T > & >::type walberla::mpi::GenericRecvBuffer< T >::get ( V & value )

private

Implements operator>> without debugging system.

Returns: Reference to the receive buffer.

◆ isEmpty()

template<typename T >

bool walberla::mpi::GenericRecvBuffer< T >::isEmpty

inline

Returns true if the receive buffer is empty.

Returns: true if the receive buffer is empty, false if it is not.

◆ maxSize()

template<typename T >

size_t walberla::mpi::GenericRecvBuffer< T >::maxSize

inline

Returns the maximum possible size of the receive buffer.

Returns: The maximum possible size.

◆ operator=() [1/3]

template<typename T >

GenericRecvBuffer< T > & walberla::mpi::GenericRecvBuffer< T >::operator= ( const GenericRecvBuffer< T > & rb )

Copy assignment operator for RecvBuffer.

Parameters

rb	The receive buffer to be copied.

Returns: Reference to the assigned receive buffer.

◆ operator=() [2/3]

template<typename T = unsigned char>

template<typename G >

GenericRecvBuffer& walberla::mpi::GenericRecvBuffer< T >::operator= ( const GenericSendBuffer< T, G > & sb )

◆ operator=() [3/3]

template<typename T = unsigned char>

template<typename G >

GenericRecvBuffer<T>& walberla::mpi::GenericRecvBuffer< T >::operator= ( const GenericSendBuffer< T, G > & sb )

◆ operator>>()

template<typename T >

template<typename V >

std::enable_if< std::is_arithmetic< V >::value||std::is_enum< V >::value, GenericRecvBuffer< T > & >::type walberla::mpi::GenericRecvBuffer< T >::operator>> ( V & value )

Reads a built-in data value from the receive buffer.

Returns: Reference to the receive buffer.

This function extracts one data value of built-in data type from the receive buffer.

Note: This operator may only be used for built-in data types. The attempt to use a user-defined data type results in a compile time error!

◆ peek()

template<typename T >

template<typename V >

void walberla::mpi::GenericRecvBuffer< T >::peek ( V & value ) const

inline

Reads a built-in data value from the receive buffer without extracting it.

Returns: void

This function reads the next built-in data value of type V from the receive buffer without extracting/removing it from the buffer.

◆ ptr()

template<typename T >

T * walberla::mpi::GenericRecvBuffer< T >::ptr

inline

Returns a pointer to the first element of the receive buffer.

Returns: Pointer to the first element of the receive buffer.

This utility function enables the RecvBuffer to be used directly as receive buffer in MPI receive functions. Note however, that this operation is only allowed for a reinitialized receive buffer (for instance via the resize() function).

using namespace pe;
 
// Preparing a receive buffer for a message of 50 bytes
RecvBuffer<byte> buffer;
buffer.resize( 50 );
 
// Receiving an MPI message from process 0 in a blocking MPI_Recv() function
MPI_Status status;
MPI_Recv( buffer.ptr(), buffer.size(), MPI_BYTE, 0, MPI_ANY_TAG, MPI_COMM_WORLD, status );

◆ readDebugMarker()

template<typename T >

void walberla::mpi::GenericRecvBuffer< T >::readDebugMarker ( const char * marker )

inline

Reads debug marker and raises assert when marker does not match.

◆ reserve()

template<typename T >

void walberla::mpi::GenericRecvBuffer< T >::reserve ( size_t newCapacity )

inline

Setting the minimum capacity of the receive buffer.

Parameters

newCapacity The new minimum capacity of the receive buffer.

Returns: void

This function reserves at least newCapacity elements of data type T for the receive buffer. Note that this operation involves a complete reset of the receive buffer!

◆ reset()

template<typename T >

void walberla::mpi::GenericRecvBuffer< T >::reset

inline

Clearing the receive buffer.

Returns: void

This function performs a complete reset of the receive buffer - including the deletion of allocated memory!

◆ resize()

template<typename T >

void walberla::mpi::GenericRecvBuffer< T >::resize ( size_t newSize )

inline

Changing the size of the receive buffer.

Parameters

newSize The new size of the receive buffer.

Returns: void

This function resizes the receive buffer to the given size newSize. Note that this operation does not preserve the current contents of the receive buffer!

◆ size()

template<typename T >

size_t walberla::mpi::GenericRecvBuffer< T >::size

inline

Returns the current size of the receive buffer.

Returns: The current size.

◆ skip()

template<typename T >

T * walberla::mpi::GenericRecvBuffer< T >::skip ( size_t elements )

inline

Skipping the given number of elements.

Parameters

elements The number of elements to be skipped.

Returns: void

This function skips element receive buffer elements of type T.

Member Data Documentation

◆ begin_

template<typename T = unsigned char>

T* walberla::mpi::GenericRecvBuffer< T >::begin_

private

Pointer to the first element of the receive buffer.

◆ capacity_

template<typename T = unsigned char>

size_t walberla::mpi::GenericRecvBuffer< T >::capacity_

private

The current size of the receive buffer.

◆ cur_

template<typename T = unsigned char>

T* walberla::mpi::GenericRecvBuffer< T >::cur_

private

Pointer to the current element of the receive buffer.

◆ end_

template<typename T = unsigned char>

T* walberla::mpi::GenericRecvBuffer< T >::end_

private

Pointer to the last element of the receive buffer.

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

/builds/administration/walberla-website/walberla/src/core/mpi/RecvBuffer.h

Detailed Description

template<typename T = unsigned char> class walberla::mpi::GenericRecvBuffer< T >

Public Types

Public Member Functions

Private Attributes

Utility functions

Member Typedef Documentation

◆ ElementType

Constructor & Destructor Documentation

◆ GenericRecvBuffer() [1/3]

◆ GenericRecvBuffer() [2/3]

◆ GenericRecvBuffer() [3/3]

◆ ~GenericRecvBuffer()

Member Function Documentation

◆ capacity()

◆ clear()

◆ get()

◆ isEmpty()

◆ maxSize()

◆ operator=() [1/3]

◆ operator=() [2/3]

◆ operator=() [3/3]

◆ operator>>()

◆ peek()

◆ ptr()

◆ readDebugMarker()

◆ reserve()

◆ reset()

◆ resize()

◆ size()

◆ skip()

Member Data Documentation

◆ begin_

◆ capacity_

◆ cur_

◆ end_

template<typename T = unsigned char>
class walberla::mpi::GenericRecvBuffer< T >