DeviceBuffer< T > Class Template Reference

Implements a smart buffer specifically designed for character device drivers. More...

#include <DeviceBuffer.hxx>

Inheritance diagram for DeviceBuffer< T >:

Public Types
typedef T	member_type

Public Member Functions
void	destroy ()
	Destroy an existing DeviceBuffer instance.
size_t	put (const T *buf, size_t items)
	Insert a number of items to the buffer.
size_t	get (T *buf, size_t items)
	remove a number of items from the buffer.
size_t	data_read_pointer (T **buf)
	Get a reference to the current location in the buffer for read.
size_t	data_write_pointer (T **buf)
	Get a reference to the current location in the buffer for write.
Public Member Functions inherited from DeviceBufferBase
void	signal_condition ()
	Signal the wakeup condition.
void	signal_condition_from_isr ()
	Signal the wakeup condition from an ISR context.
void	flush ()
	flush all the data out of the buffer and reset the buffer.
size_t	pending ()
	Return the number of items in the queue.
size_t	space ()
	Return the number of items for which space is available.
void	select_insert ()
	Add client to list of clients needing woken.
size_t	consume (size_t items)
	Remove a number of items from the buffer by advancing the readIndex.
size_t	advance (size_t items)
	Add a number of items to the buffer by advancing the writeIndex.

Static Public Member Functions
static DeviceBuffer *	create (size_t size, size_t level=0)
	Create a DeviceBuffer instance.
static constexpr unsigned	member_size ()

Private Member Functions
	DeviceBuffer (size_t size, size_t level)
	Constructor.
	~DeviceBuffer ()
	Destructor.
	DISALLOW_COPY_AND_ASSIGN (DeviceBuffer)

Private Attributes
T	data []
	buffer data

Additional Inherited Members
Protected Member Functions inherited from DeviceBufferBase
	DeviceBufferBase (size_t size, size_t level)
	Constructor.
	~DeviceBufferBase ()
	Destructor.
Protected Attributes inherited from DeviceBufferBase
uint16_t	level
	level of space required in buffer in order to wakeup, 0 if unused
uint16_t	size
	size in items of buffer
uint16_t	count
	total number of items in buffer
uint16_t	readIndex
	read index
uint16_t	writeIndex
	write index

Detailed Description

template<typename T>
class DeviceBuffer< T >

Implements a smart buffer specifically designed for character device drivers.

Technically, the private metadata for the size and index counters should more properly be implemented as size_t types. The choice of uint16_t types is simply to save memory as 2^16 is normally a reasonable maximum size for this type of metadata.

Definition at line 215 of file DeviceBuffer.hxx.

Member Typedef Documentation

member_type

template<typename T >

typedef T DeviceBuffer< T >::member_type

Definition at line 236 of file DeviceBuffer.hxx.

Constructor & Destructor Documentation

DeviceBuffer()

template<typename T >

DeviceBuffer< T >::DeviceBuffer ( size_t  size, size_t  level  )

inlineprivate

Constructor.

Parameters

size	size in items for the buffer.
level	minimum amount of space required in buffer to restart transmitting, unused for receive.

Definition at line 337 of file DeviceBuffer.hxx.

~DeviceBuffer()

template<typename T >

DeviceBuffer< T >::~DeviceBuffer ( )

inlineprivate

Destructor.

Definition at line 344 of file DeviceBuffer.hxx.

Member Function Documentation

create()

template<typename T >

static DeviceBuffer * DeviceBuffer< T >::create ( size_t  size, size_t  level = 0  )

inlinestatic

Create a DeviceBuffer instance.

Parameters

size	size in items for the DeviceBuffer
level	minimum amount of space required in buffer to restart transmitting, unused for receive.

Returns

newly created DeviceBuffer instance

Definition at line 224 of file DeviceBuffer.hxx.

data_read_pointer()

template<typename T >

size_t DeviceBuffer< T >::data_read_pointer ( T **  buf )

inline

Get a reference to the current location in the buffer for read.

Parameters

buf	location to store resulting reference

Returns

number of items in continuous memory. May be less than total number of items in the buffer.

Definition at line 304 of file DeviceBuffer.hxx.

data_write_pointer()

template<typename T >

size_t DeviceBuffer< T >::data_write_pointer ( T **  buf )

inline

Get a reference to the current location in the buffer for write.

Parameters

buf	location to store resulting reference

Returns

amount of space in continuous memory. May be less than total amount of space avaiable.

Definition at line 320 of file DeviceBuffer.hxx.

destroy()

template<typename T >

void DeviceBuffer< T >::destroy ( )

inline

Destroy an existing DeviceBuffer instance.

Definition at line 248 of file DeviceBuffer.hxx.

get()

template<typename T >

size_t DeviceBuffer< T >::get ( T *  buf, size_t  items  )

inline

remove a number of items from the buffer.

Parameters

buf	reference to the data removed
items	total number of items to remove

Returns

total number of items removed

Definition at line 281 of file DeviceBuffer.hxx.

member_size()

template<typename T >

static constexpr unsigned DeviceBuffer< T >::member_size ( )

inlinestaticconstexpr

Returns

the size of each member in bytes.

Definition at line 239 of file DeviceBuffer.hxx.

put()

template<typename T >

size_t DeviceBuffer< T >::put ( const T *  buf, size_t  items  )

inline

Insert a number of items to the buffer.

Parameters

buf	reference to the first item to insert
items	total number of items to insert

Returns

total number of items inserted

Definition at line 258 of file DeviceBuffer.hxx.

Member Data Documentation

data

template<typename T >

T DeviceBuffer< T >::data[]

private

buffer data

Definition at line 351 of file DeviceBuffer.hxx.

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

• DeviceBuffer.hxx