#include <alsatimer.h>

Inheritance diagram for Timer:

Signals
void	timerExpired (int ticks, int msecs)
	This signal is emitted when the timer has expired, if there is not an event hander installed. More...

Public Member Functions
	Timer (int cls, int scls, int card, int dev, int sdev, int openMode, QObject *parent=nullptr)
	Constructor. More...

	Timer (const QString &deviceName, int openMode, QObject *parent=nullptr)
	Constructor. More...

	Timer (const QString &deviceName, int openMode, snd_config_t config, QObject parent=nullptr)
	Constructor. More...

	Timer (TimerId &id, int openMode, QObject *parent=nullptr)
	Constructor Open flags can be a combination of the following constants: More...

virtual	~Timer ()
	Destructor.

snd_timer_t *	getHandle ()
	Gets the ALSA timer object. More...

TimerInfo &	getTimerInfo ()
	Gets the timer info object. More...

TimerStatus &	getTimerStatus ()
	Gets the timer status. More...

void	setTimerParams (const TimerParams &params)
	Sets the timer parameters. More...

void	start ()
	Start rolling the timer.

void	stop ()
	Stop rolling the timer.

void	continueRunning ()
	Continue rolling the timer.

void	addAsyncTimerHandler (snd_async_callback_t callback, void *private_data)
	Adds an asynchronous timer handler function. More...

int	getPollDescriptorsCount ()
	Gets the count of poll descriptors. More...

void	pollDescriptors (struct pollfd *pfds, unsigned int space)
	Gets poll descriptors. More...

void	pollDescriptorsRevents (struct pollfd pfds, unsigned int nfds, unsigned short revents)
	Gets returned events from poll descriptors. More...

ssize_t	read (void *buffer, size_t size)
	Read bytes from the timer handle. More...

snd_timer_t *	getTimerHandle ()
	Gets the ALSA timer handle. More...

void	setHandler (TimerEventHandler *h)
	Sets an event handler providing a method to be called when a timer expires. More...

void	startEvents ()
	Starts the events dispatching thread.

void	stopEvents ()
	Stops the events dispatching thread.

Static Public Member Functions
static TimerId	bestGlobalTimerId ()
	Check and return the best available global TimerId in the system, meaning the timer with higher frequency (or lesser period, resolution). More...

static Timer *	bestGlobalTimer (int openMode, QObject *parent=nullptr)
	Check and return the best available global Timer in the system, meaning the timer with higher frequency (or lesser period, resolution). More...

Protected Member Functions
void	doEvents ()
	Internal function to deliver the timer events using one of the two available methods: More...

Detailed Description

ALSA Timer management.

This class represents an ALSA timer object.

Examples: sysinfo.cpp.

Definition at line 283 of file alsatimer.h.

Constructor & Destructor Documentation

◆ Timer() [1/4]

Timer	(	int	cls,
		int	scls,
		int	card,
		int	dev,
		int	sdev,
		int	openMode,
		QObject *	parent = `nullptr`
	)

Constructor.

Open flags can be a combination of the following constants:

SND_TIMER_OPEN_NONBLOCK: non-blocking behavior
SND_TIMER_OPEN_TREAD: enhanced read, use time-stamps and event notification

Parameters

cls	Class
scls	Subclass
card	Card
dev	Device
sdev	Subdevice
openMode	Open mode flags bitmap
parent	Optional parent object

Definition at line 1121 of file alsatimer.cpp.

References DRUMSTICK_ALSA_CHECK_ERROR.

◆ Timer() [2/4]

Timer	(	const QString &	deviceName,
		int	openMode,
		QObject *	parent = `nullptr`
	)

Constructor.

Open flags can be a combination of the following constants:

SND_TIMER_OPEN_NONBLOCK: non-blocking behavior
SND_TIMER_OPEN_TREAD: enhanced read, use time-stamps and event notification

Parameters

deviceName	Name of the device
openMode	Open mode flags bitmap
parent	Optional parent object

Definition at line 1042 of file alsatimer.cpp.

References DRUMSTICK_ALSA_CHECK_ERROR.

◆ Timer() [3/4]

Timer	(	const QString &	deviceName,
		int	openMode,
		snd_config_t *	conf,
		QObject *	parent = `nullptr`
	)

Constructor.

Open flags can be a combination of the following constants:

SND_TIMER_OPEN_NONBLOCK: non-blocking behavior
SND_TIMER_OPEN_TREAD: enhanced read, use time-stamps and event notification

Parameters

deviceName	Name of the device
openMode	Open mode flags bitmap
conf	ALSA configuration object pointer
parent	Optional parent object

Definition at line 1065 of file alsatimer.cpp.

References DRUMSTICK_ALSA_CHECK_ERROR.

◆ Timer() [4/4]

Timer	(	TimerId &	id,
		int	openMode,
		QObject *	parent = `nullptr`
	)

Constructor Open flags can be a combination of the following constants:

SND_TIMER_OPEN_NONBLOCK: non-blocking behavior
SND_TIMER_OPEN_TREAD: enhanced read, use time-stamps and event notification

Parameters

id	TimerId object reference
openMode	Open mode flags bitmap
parent	Optional parent object

Definition at line 1089 of file alsatimer.cpp.

References DRUMSTICK_ALSA_CHECK_ERROR.

Member Function Documentation

◆ addAsyncTimerHandler()

void addAsyncTimerHandler	(	snd_async_callback_t	callback,
		void *	private_data
	)

Adds an asynchronous timer handler function.

Parameters

callback	Function handler
private_data	Any data that will be passed to the callback

Definition at line 1156 of file alsatimer.cpp.

References DRUMSTICK_ALSA_CHECK_WARNING.

◆ bestGlobalTimer()

Timer * bestGlobalTimer	(	int	openMode,
		QObject *	parent = `nullptr`
	)

static

Check and return the best available global Timer in the system, meaning the timer with higher frequency (or lesser period, resolution).

Parameters

openMode	Open mode flags
parent	Optional parent object

Returns: A new Timer instance pointer

Definition at line 1398 of file alsatimer.cpp.

References Timer::bestGlobalTimerId().

◆ bestGlobalTimerId()

TimerId bestGlobalTimerId ( )

static

Check and return the best available global TimerId in the system, meaning the timer with higher frequency (or lesser period, resolution).

Returns: A TimerId object

Since: 0.3.0

Definition at line 1335 of file alsatimer.cpp.

Referenced by Timer::bestGlobalTimer().

◆ doEvents()

void doEvents ( )

protected

Internal function to deliver the timer events using one of the two available methods:

TimerEventHandler instance pointer provided in Timer::setHandler()
A signal Timer::timerExpired() is emitted, otherwise

Definition at line 1284 of file alsatimer.cpp.

References TimerEventHandler::handleTimerEvent(), Timer::read(), and Timer::timerExpired().

◆ getHandle()

snd_timer_t * getHandle ( )

inline

Gets the ALSA timer object.

Returns: ALSA timer object pointer.

Definition at line 325 of file alsatimer.h.

◆ getPollDescriptorsCount()

int getPollDescriptorsCount ( )

Gets the count of poll descriptors.

Returns: Count of poll descriptors

Definition at line 1176 of file alsatimer.cpp.

◆ getTimerHandle()

snd_timer_t * getTimerHandle ( )

Gets the ALSA timer handle.

Returns: ALSA timer handle

Definition at line 1166 of file alsatimer.cpp.

◆ getTimerInfo()

TimerInfo & getTimerInfo ( )

Gets the timer info object.

Returns: TimerInfo object reference

Examples: sysinfo.cpp.

Definition at line 1209 of file alsatimer.cpp.

◆ getTimerStatus()

TimerStatus & getTimerStatus ( )

Gets the timer status.

Returns: TimerStatus object reference

Definition at line 1230 of file alsatimer.cpp.

References DRUMSTICK_ALSA_CHECK_WARNING.

Referenced by Timer::startEvents().

◆ pollDescriptors()

void pollDescriptors	(	struct pollfd *	pfds,
		unsigned int	space
	)

Gets poll descriptors.

Parameters

pfds	Pointer to a pollfd array
space	Number of pollfd elements available

Definition at line 1187 of file alsatimer.cpp.

References DRUMSTICK_ALSA_CHECK_WARNING.

◆ pollDescriptorsRevents()

void pollDescriptorsRevents	(	struct pollfd *	pfds,
		unsigned int	nfds,
		unsigned short *	revents
	)

Gets returned events from poll descriptors.

Parameters

pfds	Pointer to a pollfd array
nfds	Number of pollfd elements available
revents	Returned events

Definition at line 1199 of file alsatimer.cpp.

References DRUMSTICK_ALSA_CHECK_WARNING.

◆ read()

ssize_t read	(	void *	buffer,
		size_t	size
	)

Read bytes from the timer handle.

Parameters

buffer	Buffer to store the input bytes
size	Input buffer size in bytes

Returns: Bytes read from the timer

Definition at line 1270 of file alsatimer.cpp.

Referenced by Timer::doEvents().

◆ setHandler()

void setHandler ( TimerEventHandler * h )

inline

Sets an event handler providing a method to be called when a timer expires.

Parameters

h	A TimerEventHandler instance.

Definition at line 344 of file alsatimer.h.

◆ setTimerParams()

void setTimerParams ( const TimerParams & params )

Sets the timer parameters.

Parameters

params TimerParams object reference

Definition at line 1220 of file alsatimer.cpp.

References DRUMSTICK_ALSA_CHECK_WARNING.

◆ timerExpired

void timerExpired	(	int	ticks,
		int	msecs
	)

signal

This signal is emitted when the timer has expired, if there is not an event hander installed.

Parameters

ticks	The time in ticks.
msecs	The time in milliseconds.

Referenced by Timer::doEvents().

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

Signals

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ Timer() [1/4]

◆ Timer() [2/4]

◆ Timer() [3/4]

◆ Timer() [4/4]

Member Function Documentation

◆ addAsyncTimerHandler()

◆ bestGlobalTimer()

◆ bestGlobalTimerId()

◆ doEvents()

◆ getHandle()

◆ getPollDescriptorsCount()

◆ getTimerHandle()

◆ getTimerInfo()

◆ getTimerStatus()

◆ pollDescriptors()

◆ pollDescriptorsRevents()

◆ read()

◆ setHandler()

◆ setTimerParams()

◆ timerExpired