#include <FileDescriptorActivity.hpp>

Inheritance diagram for RTT::extras::FileDescriptorActivity:

Public Member Functions
virtual bool	breakLoop ()
void	clearAllWatches ()
	FileDescriptorActivity (int priority, base::RunnableInterface *_r=0, const std::string &name="FileDescriptorActivity")
	FileDescriptorActivity (int scheduler, int priority, base::RunnableInterface *_r=0, const std::string &name="FileDescriptorActivity")
	FileDescriptorActivity (int scheduler, int priority, Seconds period, base::RunnableInterface *_r=0, const std::string &name="FileDescriptorActivity")
	FileDescriptorActivity (int scheduler, int priority, Seconds period, unsigned cpu_affinity, base::RunnableInterface *_r=0, const std::string &name="FileDescriptorActivity")
virtual Seconds	getPeriod () const
	Get the _intended_ period (not the actual running period)
int	getTimeout () const
int	getTimeout_us () const
bool	hasError () const
bool	hasTimeout () const
bool	isRunning () const
bool	isUpdated (int fd) const
bool	isWatched (int fd) const
virtual void	loop ()
virtual bool	setPeriod (Seconds period)
	Set the _intended_ period (not the actual running period)
void	setTimeout (int timeout)
void	setTimeout_us (int timeout_us)
virtual bool	start ()
virtual void	step ()
virtual bool	stop ()
virtual bool	trigger ()
void	unwatch (int fd)
void	watch (int fd)
virtual	~FileDescriptorActivity ()
Private Member Functions
void	triggerUpdateSets ()
Private Attributes
fd_set	m_fd_set
fd_set	m_fd_work
bool	m_has_error
bool	m_has_timeout
int	m_interrupt_pipe [2]
RTT::os::Mutex	m_lock
	intended period
Seconds	m_period
	timeout in microseconds
bool	m_running
int	m_timeout_us
std::set< int >	m_watched_fds
Static Private Attributes
static const char	CMD_BREAK_LOOP = 0
static const char	CMD_TRIGGER = 1
static const char	CMD_UPDATE_SETS = 2

Detailed Description

An activity which is triggered by the availability of data on a set of file descriptors. step() (and hence the base::RunnableInterface's step() method) is called when data is available or when an error is encountered on the file descriptor.

To use it, one must add the file descriptors to watch in the task's configureHook()

FileDescriptorActivity* fd_activity = dynamic_cast<FileDescriptorActivity*>(getActivity().get()); if (fd_activity) { fd_activity->watch(device_fd); // optional, set a timeout in milliseconds fd_activity->setTimeout(1000); // or in microseconds fd_activity->setTimeout_us(1000); }

Then, updateHook() and -- when in ERROR state -- errorHook() will be called when one of these three events happen:

new data is available on one of the watched FDs
an error happens on one of the watched FDs
the timeout is reached

The different cases can be tested in updateHook() as follows:

FileDescriptorActivity* fd_activity = dynamic_cast<FileDescriptorActivity*>(getActivity().get()); if (fd_activity) { if (fd_activity->hasError()) { } else if (fd_activity->hasTimeout()) { } else { // If there is more than one FD, discriminate. Otherwise, // we don't need to use isUpdated if (fd_activity->isUpdated(device_fd)) { } else if (fd_activity->isUpdated(another_fd)) { } } }

Definition at line 103 of file FileDescriptorActivity.hpp.

Constructor & Destructor Documentation

FileDescriptorActivity::FileDescriptorActivity	(	int	priority,
		base::RunnableInterface *	_r = `0`,
		const std::string &	name = `"FileDescriptorActivity"`
	)

Create a FileDescriptorActivity with a given priority and base::RunnableInterface instance. The default scheduler for NonPeriodicActivity objects is ORO_SCHED_RT.

Parameters:

priority	The priority of the underlying thread.
_r	The optional runner, if none, this->loop() is called.
name	The name of the underlying thread.

Create a FileDescriptorActivity with a given priority and RunnableInterface instance. The default scheduler for NonPeriodicActivity objects is ORO_SCHED_RT.

Parameters:

priority	The priority of the underlying thread.
_r	The optional runner, if none, this->loop() is called.

Definition at line 79 of file FileDescriptorActivity.cpp.

FileDescriptorActivity::FileDescriptorActivity	(	int	scheduler,
		int	priority,
		base::RunnableInterface *	_r = `0`,
		const std::string &	name = `"FileDescriptorActivity"`
	)

Create a FileDescriptorActivity with a given scheduler type, priority and base::RunnableInterface instance.

Parameters:

scheduler	The scheduler in which the activitie's thread must run. Use ORO_SCHED_OTHER or ORO_SCHED_RT.
priority	The priority of the underlying thread.
_r	The optional runner, if none, this->loop() is called.
name	The name of the underlying thread.

Create a FileDescriptorActivity with a given scheduler type, priority and RunnableInterface instance.

Parameters:

scheduler	The scheduler in which the activitie's thread must run. Use ORO_SCHED_OTHER or ORO_SCHED_RT.
priority	The priority of the underlying thread.
_r	The optional runner, if none, this->loop() is called.

Definition at line 101 of file FileDescriptorActivity.cpp.

FileDescriptorActivity::FileDescriptorActivity	(	int	scheduler,
		int	priority,
		Seconds	period,
		base::RunnableInterface *	_r = `0`,
		const std::string &	name = `"FileDescriptorActivity"`
	)

Create a FileDescriptorActivity with a given scheduler type, priority, _intended_ period, and RunnableInterface instance.

Parameters:

scheduler	The scheduler in which the activitie's thread must run. Use ORO_SCHED_OTHER or ORO_SCHED_RT.
priority	The priority of the underlying thread.
period	The _intended_ periodicity of the activity
_r	The optional runner, if none, this->loop() is called.
name	The name of the underlying thread.

Definition at line 114 of file FileDescriptorActivity.cpp.

FileDescriptorActivity::FileDescriptorActivity	(	int	scheduler,
		int	priority,
		Seconds	period,
		unsigned	cpu_affinity,
		base::RunnableInterface *	_r = `0`,
		const std::string &	name = `"FileDescriptorActivity"`
	)

Create a FileDescriptorActivity with a given scheduler type, priority, _intended_ period, CPU affinity, and RunnableInterface instance.

Parameters:

scheduler	The scheduler in which the activitie's thread must run. Use ORO_SCHED_OTHER or ORO_SCHED_RT.
priority	The priority of the underlying thread.
period	The _intended_ periodicity of the activity
cpu_affinity	The prefered cpu to run on (a mask)
_r	The optional runner, if none, this->loop() is called.
name	The name of the underlying thread.

Definition at line 127 of file FileDescriptorActivity.cpp.

FileDescriptorActivity::~FileDescriptorActivity ( ) [virtual]

Definition at line 140 of file FileDescriptorActivity.cpp.

Member Function Documentation

bool FileDescriptorActivity::breakLoop ( ) [virtual]

See also:: base::RunnableInterface::breakLoop()

Reimplemented from RTT::Activity.

Definition at line 357 of file FileDescriptorActivity.cpp.

void FileDescriptorActivity::clearAllWatches ( )

Remove all FDs that are currently being watched

Definition at line 195 of file FileDescriptorActivity.cpp.

Seconds FileDescriptorActivity::getPeriod ( ) const [virtual]

Get the _intended_ period (not the actual running period)

Reimplemented from RTT::Activity.

Definition at line 145 of file FileDescriptorActivity.cpp.

int FileDescriptorActivity::getTimeout ( ) const

Get the timeout, in milliseconds, for waiting on the IO. Set to 0 for blocking behaviour (no timeout).

Definition at line 158 of file FileDescriptorActivity.cpp.

int FileDescriptorActivity::getTimeout_us ( ) const

Get the timeout, in microseconds, for waiting on the IO. Set to 0 for blocking behaviour (no timeout).

Definition at line 160 of file FileDescriptorActivity.cpp.

bool FileDescriptorActivity::hasError ( ) const

True if one of the file descriptors has a problem (for instance it has been closed)

This should only be used from within the base::RunnableInterface this activity is driving, i.e. in TaskContext::updateHook() or TaskContext::errorHook().

Definition at line 209 of file FileDescriptorActivity.cpp.

bool FileDescriptorActivity::hasTimeout ( ) const

True if the base::RunnableInterface has been triggered because of a timeout, instead of because of new data is available.

This should only be used from within the base::RunnableInterface this activity is driving, i.e. in TaskContext::updateHook() or TaskContext::errorHook().

Definition at line 211 of file FileDescriptorActivity.cpp.

bool FileDescriptorActivity::isRunning ( ) const [virtual]

Query if the activity is initialized and executing. This is more strict than isActive(), it is only true after initialize() is executed and before finalize() is executed. More-over, an Activity may decide to be temporarily not running (not executing code), waiting for a signal to proceed. If this->isActive() and !this->isRunning() then the Activity is in a waiting state.

Returns:: true if it is running, false otherwise

Reimplemented from RTT::Activity.

Definition at line 156 of file FileDescriptorActivity.cpp.

bool FileDescriptorActivity::isUpdated ( int fd ) const

True if this specific FD has new data.

This should only be used from within the base::RunnableInterface this activity is driving, i.e. in TaskContext::updateHook() or TaskContext::errorHook().

Definition at line 207 of file FileDescriptorActivity.cpp.

bool FileDescriptorActivity::isWatched ( int fd ) const

True if this specific FD is being watched by the activity

Definition at line 213 of file FileDescriptorActivity.cpp.

void FileDescriptorActivity::loop ( ) [virtual]

See also:: base::RunnableInterface::loop()

Reimplemented from RTT::Activity.

Definition at line 258 of file FileDescriptorActivity.cpp.

bool FileDescriptorActivity::setPeriod ( Seconds period ) [virtual]

Set the _intended_ period (not the actual running period)

Reimplemented from RTT::Activity.

Definition at line 148 of file FileDescriptorActivity.cpp.

void FileDescriptorActivity::setTimeout ( int timeout )

Sets the timeout, in milliseconds, for waiting on the IO. Set to 0 for blocking behaviour (no timeout).

Precondition:: 0 <= timeout (otherwise an error is logged and timeout is ignored)

Definition at line 162 of file FileDescriptorActivity.cpp.

void FileDescriptorActivity::setTimeout_us ( int timeout_us )

Sets the timeout, in microseconds, for waiting on the IO. Set to 0 for blocking behaviour (no timeout).

Precondition:: 0 <= timeout (otherwise an error is logged and timeout_us is ignored)

Definition at line 166 of file FileDescriptorActivity.cpp.

bool FileDescriptorActivity::start ( ) [virtual]

Start the activity. This will call RunnableInterface::initialize() and upon success, effectively start the activity, by running the RunnableInterface::step() or RunnableInterface::loop() in a thread.

See also:: isPeriodic()

Returns:: true if the activity is started, false otherwise

Reimplemented from RTT::Activity.

Definition at line 217 of file FileDescriptorActivity.cpp.

void FileDescriptorActivity::step ( ) [virtual]

Called by loop() when data is available on the file descriptor. By default, it calls step() on the associated runner interface (if any)

Reimplemented from RTT::Activity.

Definition at line 368 of file FileDescriptorActivity.cpp.

bool FileDescriptorActivity::stop ( ) [virtual]

Stop the activity This will stop the activity by removing it from the 'run-queue' of a thread or call RunnableInterface::breakLoop(). If no errors occured, RunnableInterface::finalize() is called.