RTT::os::Thread Class Reference

#include <Thread.hpp>

Inheritance diagram for RTT::os::Thread:

Public Member Functions
virtual unsigned	getCpuAffinity () const
virtual unsigned	getCpuAffinity () const
virtual int	getMaxOverrun () const
virtual int	getMaxOverrun () const
virtual const char *	getName () const
virtual const char *	getName () const
virtual Seconds	getPeriod () const
void	getPeriod (secs &s, nsecs &ns) const
virtual Seconds	getPeriod () const
void	getPeriod (secs &s, nsecs &ns) const
virtual nsecs	getPeriodNS () const
virtual nsecs	getPeriodNS () const
virtual int	getPriority () const
virtual int	getPriority () const
virtual int	getScheduler () const
virtual int	getScheduler () const
virtual const RTOS_TASK *	getTask () const
virtual RTOS_TASK *	getTask ()
virtual const RTOS_TASK *	getTask () const
virtual RTOS_TASK *	getTask ()
virtual bool	isActive () const
virtual bool	isActive () const
virtual bool	isPeriodic () const
virtual bool	isPeriodic () const
virtual bool	isRunning () const
virtual bool	isRunning () const
virtual bool	setCpuAffinity (unsigned cpu_affinity)
virtual bool	setCpuAffinity (unsigned cpu_affinity)
virtual void	setMaxOverrun (int m)
virtual void	setMaxOverrun (int m)
bool	setPeriod (TIME_SPEC p)
bool	setPeriod (secs s, nsecs ns)
bool	setPeriod (Seconds s)
bool	setPeriod (TIME_SPEC p)
bool	setPeriod (secs s, nsecs ns)
bool	setPeriod (Seconds s)
virtual bool	setPriority (int priority)
virtual bool	setPriority (int priority)
virtual bool	setScheduler (int sched_type)
virtual bool	setScheduler (int sched_type)
virtual void	setWaitPeriodPolicy (int p)
virtual void	setWaitPeriodPolicy (int p)
virtual bool	start ()
virtual bool	start ()
virtual bool	stop ()
virtual bool	stop ()
	Thread (int scheduler, int priority, double period, unsigned cpu_affinity, const std::string &name)
	Thread (int scheduler, int priority, double period, unsigned cpu_affinity, const std::string &name)
virtual void	yield ()
virtual void	yield ()
virtual	~Thread ()
virtual	~Thread ()
Static Public Member Functions
static void	setStackSize (unsigned int ssize)
static void	setStackSize (unsigned int ssize)
Protected Member Functions
virtual bool	breakLoop ()
virtual bool	breakLoop ()
void	emergencyStop ()
void	emergencyStop ()
virtual void	finalize ()
virtual void	finalize ()
virtual bool	initialize ()
virtual bool	initialize ()
virtual void	loop ()
virtual void	loop ()
virtual void	step ()
virtual void	step ()
void	terminate ()
void	terminate ()
Private Member Functions
void	configure ()
void	configure ()
void	setup (int _priority, unsigned cpu_affinity, const std::string &name)
void	setup (int _priority, unsigned cpu_affinity, const std::string &name)
	Thread (const Thread &)
	Thread (const Thread &)
Private Attributes
bool	active
MutexRecursive	breaker
bool	inloop
int	maxOverRun
int	msched_type
NANO_TIME	period
bool	prepareForExit
RTOS_TASK	rtos_task
bool	running
rt_sem_t	sem
Static Private Attributes
static unsigned int	default_stack_size = 0
Friends
void *	thread_function (void *t)
void *	thread_function (void *t)

Detailed Description

A Thread object executes user code in its own thread.

If the underlying OS supports it, both period and priority can be changed after creation. When the period is 0, the loop() function is executed, when the period is greater than 0, the step() function is executed. Note: if the user does not implement loop(), it will call step() by default.

The main functions to implement are initialize(), step()/loop() and finalize(). initialize() is called when start() is called, and before the first step()/loop() and finalize() is called when stop() is called after the last step()/loop() returns.

behavior

When a period is set, step() is executed from the moment start() is called, and afterwards according to it's period. When stop() is called, it waits for the step() function to return and then stops the periodic execution.

Step() overruns are detected and the threshold to 'emergency stop' the thread can be set by setMaxOverrun(). Overruns must be accumulated 'on average' to trigger this behavior: one not overrunning step() compensates for one overrunning step().

periodic behaviour

The first invocation of start() invokes the initialize() function and runs the loop() method in the thread. When loop() returns the thread waits for another start() to execute loop() again. In that case, initialize() is not executed.

When stop() is called and the thread is still executing loop() and breakLoop() returns true (not the default), the stop() function succeeds and the finalize() method is called by stop(). If the thread was not executing loop(), stop will always call finalize() and return success.

The user must provide an implementation of breakLoop() returning true to make stop() work while loop() is being executed. stop() will fail and not execute finalize() if the thread executes loop() and breakLoop() is not reimplemented to return true.

, priorities, schedulers and stack sizes

These four parameters are the parameters that users wish to set for every thread created. All but stack size can be modified after creation, and if the OS permits it, modified even when the thread is using user code. All these parameters are passed to the underlying OS unmodified. In case an incorrect combination is made, the change may be rejected or adjusted to a close or safe value.

See also:: setPeriod, setScheduler, setPriority, setStackSize

Definition at line 109 of file install/include/rtt/os/Thread.hpp.

Constructor & Destructor Documentation

RTT::os::Thread::Thread	(	int	scheduler,
		int	priority,
		double	period,
		unsigned	cpu_affinity,
		const std::string &	name
	)

Create a Thread with a given scheduler type, priority and a name.

Parameters:

	scheduler	The scheduler, one of ORO_SCHED_RT or ORO_SCHED_OTHER.
	priority	The priority of the thread, this is interpreted by your RTOS.
	period	The period in seconds (eg 0.001) of the thread, or zero if not periodic.
	cpu_affinity	The cpu affinity of the thread, this is interpreted by your RTOS.
	name	The name of the Thread. May be used by your OS to identify the thread. the thread's own virtual functions are executed.

Definition at line 238 of file Thread.cpp.

RTT::os::Thread::~Thread ( ) [virtual]

Definition at line 322 of file Thread.cpp.

RTT::os::Thread::Thread ( const Thread & ) [private]

RTT::os::Thread::Thread	(	int	scheduler,
		int	priority,
		double	period,
		unsigned	cpu_affinity,
		const std::string &	name
	)

Create a Thread with a given scheduler type, priority and a name.

Parameters:

	scheduler	The scheduler, one of ORO_SCHED_RT or ORO_SCHED_OTHER.
	priority	The priority of the thread, this is interpreted by your RTOS.
	period	The period in seconds (eg 0.001) of the thread, or zero if not periodic.
	cpu_affinity	The cpu affinity of the thread, this is interpreted by your RTOS.
	name	The name of the Thread. May be used by your OS to identify the thread. the thread's own virtual functions are executed.