A wrapper class around a string-based Hub Port that buffers the outgoing bytes for a specified delay timer before sending the data off. More...

#include <BufferPort.hxx>

Inheritance diagram for BufferPort:

Classes
class	BufferTimer
	Timer that triggers the parent flow when expiring. More...

Public Member Functions
	BufferPort (Service service, HubPortInterface downstream, unsigned buffer_bytes, long long delay_nsec)
	Constructor.

bool	shutdown ()

Public Member Functions inherited from StateFlow< MessageType, QueueType >
	StateFlow (Service *service)
	Constructor.

Public Member Functions inherited from TypedStateFlow< MessageType, UntypedStateFlow< QueueType > >
	TypedStateFlow (Service *service)
	Constructor.

virtual	~TypedStateFlow ()
	Destructor.

void	send (MessageType *msg, unsigned priority=UINT_MAX) OVERRIDE
	Sends a message to the state flow for processing.

Public Member Functions inherited from UntypedStateFlow< QueueType >
	UntypedStateFlow (Service *service)
	Constructor.

Public Member Functions inherited from StateFlowWithQueue
void	notify () override
	Wakeup call arrived. Schedules *this on the executor.

bool	is_waiting ()

Public Member Functions inherited from StateFlowBase
void	run () override
	Callback from the executor.

Service *	service ()
	Return a pointer to the service I am bound to.

Public Member Functions inherited from Executable
void	test_deletion ()

Public Member Functions inherited from QMember
void	init ()
	Initiailize a QMember, in place of a public placement construction.

Public Member Functions inherited from LinkedObject< StateFlowWithQueue >
StateFlowWithQueue *	link_next ()

Public Member Functions inherited from FlowInterface< MessageType >
virtual Pool *	pool ()

virtual MessageType *	type_helper ()
	This function is never user in the code, but GDB can use it to infer the correct message types.

MessageType *	alloc ()
	Synchronously allocates a message buffer from the pool of this flow.

void	alloc_async (Executable *target)
	Asynchronously allocates a message buffer from the pool of this flow.

Private Member Functions
Action	entry () override
	Entry into the StateFlow activity.

Action	buf_alloc_done ()
	State when the allocation of output buffer completed.

void	flush_buffer ()
	Sends off any data we may have accumulated in the buffer to the downstream consumer.

void	timeout ()
	Callback from the timer.

const string &	msg ()

Private Attributes
BufferPort::BufferTimer	this
	timer instance.

LimitedPool	outputPool_
	Pool implementation that limits the number of buffers allocatable to the configuration option.

Buffer< HubData > *	tgtBuf_ {nullptr}
	Caches one output buffer to fill in the buffer flush method.

HubPortInterface *	downstream_
	Where to send output data to.

long long	delayNsec_
	How long maximum we should buffer the input data.

char *	sendBuf_
	Temporarily stores outgoing data.

unsigned	bufSize_
	How many bytes are there in the send buffer.

unsigned	bufEnd_: 24
	Offset in sendBuf_ of the first unused byte.

unsigned	timerPending_: 1
	1 if the timer is running and there will be a timer callback coming in the future.

Additional Inherited Members
Public Types inherited from TypedStateFlow< MessageType, UntypedStateFlow< QueueType > >
typedef Base::Action	Action
	Allows using Action without having StateFlowBase:: prefix in front of it.

Public Types inherited from FlowInterface< MessageType >
typedef MessageType	message_type
	Stores the message template type for external reference.

Static Public Member Functions inherited from StateFlowBase
template<class T , typename... Args>
static void	invoke_subflow_and_ignore_result (FlowInterface< Buffer< T > > *target_flow, Args &&... args)
	Calls a helper flow to perform some actions.

Static Public Member Functions inherited from LinkedObject< StateFlowWithQueue >
static StateFlowWithQueue *	link_head ()

static Atomic *	head_mu ()
	Locks the list for modification (at any entry!).

Static Public Member Functions inherited from FlowInterface< MessageType >
static MessageType *	cast_alloc (QMember *entry)
	Down casts and initializes an asynchronous allocation result to the appropriate flow's buffer type.

Protected Types inherited from UntypedStateFlow< QueueType >
typedef Action(StateFlowBase::*	Callback) ()
	State Flow callback prototype.

Protected Types inherited from StateFlowBase
typedef Action(StateFlowBase::*	Callback) ()
	State Flow callback prototype.

Protected Member Functions inherited from TypedStateFlow< MessageType, UntypedStateFlow< QueueType > >
void	release () OVERRIDE
	Unrefs the current buffer.

void	return_buffer ()
	For state flows that are operated using invoke_subflow_and_wait this is a way to hand back the buffer to the caller.

MessageType *	message ()

MessageType *	transfer_message ()
	Releases ownership of the current message.

Protected Member Functions inherited from UntypedStateFlow< QueueType >
void	send (BufferBase *msg, unsigned priority=UINT_MAX)
	Sends a message to the state flow for processing.

QMember *	queue_next (unsigned *priority) OVERRIDE
	Takes the front entry in the queue.

bool	queue_empty () OVERRIDE

Action	call_immediately (Callback c)
	Imediately call the next state upon return.

Protected Member Functions inherited from StateFlowWithQueue
	StateFlowWithQueue (Service *service)
	Constructor.

Action	exit ()
	Terminates the processing of this flow.

Action	release_and_exit ()
	Terminates the processing of the current message.

BufferBase *	message ()

BufferBase *	transfer_message ()
	Releases ownership of the current message.

void	reset_message (BufferBase *message, unsigned priority)
	Sets the current message being processed.

unsigned	priority ()

void	set_priority (unsigned priority)
	Overrides the current priority.

void	start_flow_at_init (Callback c)
	Call this from the constructor of the child class to do some work before the main queue processing loop begins.

Protected Member Functions inherited from StateFlowBase
	StateFlowBase (Service *service)
	Constructor.

	~StateFlowBase ()
	Destructor.

void	reset_flow (Callback c)
	Resets the flow to the specified state.

bool	is_state (Callback c)

bool	is_terminated ()

void	start_flow (Callback c)
	Resets the flow to the specified state and starts it.

Action	again ()
	Call the current state again via call_immediately.

Action	exit ()
	Terminate current StateFlow activity.

Action	delete_this ()
	Terminates the flow and deletes *this.

Action	set_terminated ()
	Sets the flow to terminated state.

Action	call_immediately (Callback c)
	Imediately call the next state upon return.

Action	wait ()
	Wait for an asynchronous call.

Action	wait_and_call (Callback c)
	Wait for resource to become available before proceeding to next state.

template<class T >
Action	allocate_and_call (FlowInterface< Buffer< T > > target_flow, Callback c, Pool pool=nullptr)
	Allocates a buffer from a pool and proceed to the next state when allocation is successful.

Action	allocate_and_call (Callback c, QAsync *queue)
	Allocates an entry from an asynchronous queue, and transitions to a state once the allocation is complete.

template<class T >
Buffer< T > *	full_allocation_result (FlowInterface< Buffer< T > > *target_flow)
	Takes the result of the asynchronous allocation without resetting the object.

template<class T >
T *	full_allocation_result (TypedQAsync< T > *queue)
	Takes the result of the asynchronous allocation without resetting the object.

template<class T >
void	cast_allocation_result (T **member)
	Takes the result of the asynchronous allocation without resetting the object.

template<class T >
Buffer< T > *	get_allocation_result (FlowInterface< Buffer< T > > *target_flow)
	Takes the result of the asynchronous allocation.

Action	yield_and_call (Callback c)
	Place the current flow to the back of the executor, and transition to a new state after we get the CPU again.

Action	yield ()
	Place the current flow to the back of the executor, and re-try the current state after we get the CPU again.

Action	sleep_and_call (::Timer *timer, long long timeout_nsec, Callback c)
	Suspends execution of this control flow for a specified time.

template<class T , typename... Args>
Action	invoke_subflow_and_wait (FlowInterface< Buffer< T > > *target_flow, Callback c, Args &&... args)
	Calls a helper flow to perform some actions.

Action	read_repeated (StateFlowSelectHelper helper, int fd, void buf, size_t size, Callback c, unsigned priority=Selectable::MAX_PRIO)
	Blocks until size bytes are read and then invokes the next state.

Action	read_single (StateFlowSelectHelper helper, int fd, void buf, size_t size, Callback c, unsigned priority=Selectable::MAX_PRIO)
	Attempts to read at most size_t bytes, and blocks the caller until at least one byte is read.

Action	read_nonblocking (StateFlowSelectHelper helper, int fd, void buf, size_t size, Callback c, unsigned priority=Selectable::MAX_PRIO)
	Attempts to read at most size bytes, and then invokes the next state, even if only zero bytes are available right now.

Action	read_repeated_with_timeout (StateFlowTimedSelectHelper helper, long long timeout_nsec, int fd, void buf, size_t size, Callback c, unsigned priority=Selectable::MAX_PRIO)
	Blocks until size bytes are read, or a timeout expires.

Action	internal_try_read ()
	Implementation state that gets repeatedly called upon every wakeup and tries to make progress on reading.

Action	write_repeated (StateFlowSelectHelper helper, int fd, const void buf, size_t size, Callback c, unsigned priority=Selectable::MAX_PRIO)
	Writes some data into a file descriptor, repeating the operation as necessary until all bytes are written.

Action	internal_try_write ()
	Implementation state that gets repeatedly called upon every wakeup and tries to make progress on writing.

Protected Member Functions inherited from QMember
	QMember ()
	Constructor.

	~QMember ()
	Destructor.

Protected Member Functions inherited from Atomic
void	lock ()

void	unlock ()

Protected Member Functions inherited from LinkedObject< StateFlowWithQueue >
StateFlowWithQueue *	link_this ()

	LinkedObject ()
	Constructor. Puts *this on the linked list.

	~LinkedObject ()
	Constructor. Removes *this from the linked list.

StateFlowWithQueue *	link_next ()

Static Protected Member Functions inherited from LinkedObject< StateFlowWithQueue >
static StateFlowWithQueue *	link_head ()

static Atomic *	head_mu ()
	Locks the list for modification (at any entry!).

Protected Attributes inherited from QMember
QMember *	next
	pointer to the next member in the queue

Protected Attributes inherited from LinkedObject< StateFlowWithQueue >
StateFlowWithQueue *	link_
	Linked list pointer.

Static Protected Attributes inherited from LinkedObject< StateFlowWithQueue >
static StateFlowWithQueue *	head_
	Beginning of the list.

Detailed Description

A wrapper class around a string-based Hub Port that buffers the outgoing bytes for a specified delay timer before sending the data off.

This helps accumulate more data per TCP packet and increase transmission efficiency.

Definition at line 46 of file BufferPort.hxx.

Constructor & Destructor Documentation

◆ BufferPort()

BufferPort::BufferPort	(	Service *	service,
		HubPortInterface *	downstream,
		unsigned	buffer_bytes,
		long long	delay_nsec
	)

inline

Constructor.

Parameters

service	specifies which thread to operate on. Typically the same as the calling Hub's executor.
downstream	where to send the (buffered) data onwards.
buffer_bytes	how many bytes to buffer up max.
delay_nsec	how many nanoseconds long we should buffer the output data max.

Definition at line 57 of file BufferPort.hxx.

◆ ~BufferPort()

BufferPort::~BufferPort ( )

inline

Definition at line 70 of file BufferPort.hxx.

Member Function Documentation

◆ buf_alloc_done()

Action BufferPort::buf_alloc_done ( )

inlineprivate

State when the allocation of output buffer completed.

Definition at line 156 of file BufferPort.hxx.

◆ entry()

Action BufferPort::entry ( )

inlineoverrideprivatevirtual

Entry into the StateFlow activity.

Pure virtual which must be defined by derived class.

Returns: function pointer to next state

Implements TypedStateFlow< MessageType, UntypedStateFlow< QueueType > >.

Definition at line 87 of file BufferPort.hxx.

◆ flush_buffer()

void BufferPort::flush_buffer ( )

inlineprivate

Sends off any data we may have accumulated in the buffer to the downstream consumer.

Definition at line 165 of file BufferPort.hxx.

◆ msg()

const string & BufferPort::msg ( )

inlineprivate

Returns: the current message that we are processing.

Definition at line 187 of file BufferPort.hxx.

◆ shutdown()

bool BufferPort::shutdown ( )

inline

Definition at line 75 of file BufferPort.hxx.

◆ timeout()

void BufferPort::timeout ( )

inlineprivate

Callback from the timer.

Definition at line 180 of file BufferPort.hxx.

Member Data Documentation

◆ bufEnd_

unsigned BufferPort::bufEnd_

private

Offset in sendBuf_ of the first unused byte.

Definition at line 229 of file BufferPort.hxx.

◆ bufSize_

unsigned BufferPort::bufSize_

private

How many bytes are there in the send buffer.

Definition at line 227 of file BufferPort.hxx.

◆ delayNsec_

long long BufferPort::delayNsec_

private

How long maximum we should buffer the input data.

Definition at line 223 of file BufferPort.hxx.

◆ downstream_

HubPortInterface* BufferPort::downstream_

private

Where to send output data to.

Definition at line 221 of file BufferPort.hxx.

◆ outputPool_

LimitedPool BufferPort::outputPool_

private

Initial value:

{sizeof(*tgtBuf_),

(unsigned)config_gridconnect_bridge_max_outgoing_packets()}

Pool implementation that limits the number of buffers allocatable to the configuration option.

Definition at line 216 of file BufferPort.hxx.

◆ sendBuf_

char* BufferPort::sendBuf_

private

Temporarily stores outgoing data.

Definition at line 225 of file BufferPort.hxx.

◆ tgtBuf_

Buffer<HubData>* BufferPort::tgtBuf_ {nullptr}

private

Caches one output buffer to fill in the buffer flush method.

Definition at line 219 of file BufferPort.hxx.

◆ timerPending_

unsigned BufferPort::timerPending_

private

1 if the timer is running and there will be a timer callback coming in the future.

Definition at line 232 of file BufferPort.hxx.

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

BufferPort.hxx

Classes

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ BufferPort()

◆ ~BufferPort()

Member Function Documentation

◆ buf_alloc_done()

◆ entry()

◆ flush_buffer()

◆ msg()

◆ shutdown()

◆ timeout()

Member Data Documentation

◆ bufEnd_

◆ bufSize_

◆ delayNsec_

◆ downstream_

◆ outputPool_

◆ sendBuf_

◆ tgtBuf_

◆ timerPending_