IODevice internals

Documentation on internal parts of IODevice interface - mainly for port developers. More...

Detailed Description

Documentation on internal parts of IODevice interface - mainly for port developers.

Internally, an IODevice is a pointer to a IODeviceDesc structure, that holds pointers to functions that implement the actual IODevice functionality. The port is responsible for providing a structure for each IODevice. This can be done by either defining the structures or by providing a "creator" and "destructor" functions that create and destroy such objects at runtime.

Data Structures
struct	IODeviceDesc

Typedefs
typedef struct IODeviceDesc	IODeviceDesc
typedef HALRESULT(*	IODeviceCtrlFunc )(IODevice)
typedef HALRESULT(*	IODeviceIOCtlFunc )(IODevice, unsigned int, va_list)
typedef size_t(*	IODeviceGetCountFunc )(IODevice)
typedef size_t(*	IODeviceWriteFunc )(IODevice, const void *, size_t)
typedef size_t(*	IODeviceReadFunc )(IODevice, void *, size_t)

Functions
void	IODEV_SignalReadEvent (IODevice iodevice, int count)
void	IODEV_SignalWriteEvent (IODevice iodevice, int count)

Typedef Documentation

typedef struct IODeviceDesc IODeviceDesc

IODevice structure declaration.

typedef HALRESULT(* IODeviceCtrlFunc)(IODevice)

IODevice control function type.

typedef HALRESULT(* IODeviceIOCtlFunc)(IODevice, unsigned int, va_list)

IODevice IOCtl function type.

typedef size_t(* IODeviceGetCountFunc)(IODevice)

IODevice "get count" function type.

typedef size_t(* IODeviceWriteFunc)(IODevice, const void *, size_t)

IODevice write function type.

typedef size_t(* IODeviceReadFunc)(IODevice, void *, size_t)

IODevice read function type.

Function Documentation

void IODEV_SignalReadEvent	(	IODevice	iodevice,
		int	count
	)

Signals read event from port. This function is used by ports to notify IODevice interface that a certain amount of read events has happened. It checks if a read notifier was configured for the given IODevice, and if so it signals read events to it. This in turn may trigger application threads that wait for data to unblock.

This function should only be used by ports.

Parameters

iodevice	IODevice
count	number of read events to signal

void IODEV_SignalWriteEvent	(	IODevice	iodevice,
		int	count
	)

Signals write event from port. This function is used by ports to notify IODevice interface that a certain amount of write events has happened. It checks if a write notifier was configured for the given IODevice, and if so it signals write events to it. This in turn may trigger application threads that wait for end of write to unblock.

This function should only be used by ports.

Parameters

iodevice	IODevice
count	number of write events to signal