libthreadar::condition Class Reference

Wrapper around the Posix pthread_cond_t object and its associated mutex. More...

#include <condition.hpp>

Inherits libthreadar::mutex.

Public Member Functions
	condition (unsigned int num=1)
	constructor More...
	condition (const condition &ref)=delete
	no copy constructor
	condition (condition &&ref)=default
	no move constructor
condition &	operator= (const condition &ref)=delete
	no assignment operator
condition &	operator= (condition &&ref) noexcept=default
	no move operator
	~condition ()
	destructor
void	wait (unsigned int instance=0)
	put the calling thread on hold waiting for another thread to call signal() More...
void	signal (unsigned int instance=0)
	awakes a single thread suspended for having called wait() on the condition given in argument More...
void	broadcast (unsigned int instance=0)
	awakes all threads suspended for having called wait() on the condition given in argument More...
unsigned int	get_waiting_thread_count (unsigned int instance=0) const
	return the number of thread currently waiting on that condition More...
Public Member Functions inherited from libthreadar::mutex
	mutex ()
	constructor
	mutex (const mutex &ref)=delete
	no copy constructor
	mutex (mutex &&ref)=default
	no move constructor
mutex &	operator= (const mutex &ref)=delete
	no assignment operator
mutex &	operator= (mutex &&ref) noexcept=default
	no move operator
virtual	~mutex ()
	destructor
void	lock ()
	lock the mutex More...
void	unlock ()
	unlock the mutex More...
bool	try_lock ()
	Tells whether calling lock() would currently suspend the caller or not. More...

Additional Inherited Members
Protected Attributes inherited from libthreadar::mutex
pthread_mutex_t	mut

Detailed Description

Wrapper around the Posix pthread_cond_t object and its associated mutex.

Class condition inherits from the mutex class and thus provides the lock(), unlock() and try_lock() methods. These must be used around the wait(), signal() or broadcast() methods brought by this class, see details for each of them.

Note

each object share a user defined set of condition on the same mutex as defined at constructor time. wait() takes as argument the condition number and will be awaken by a signal() or broadcast() having this same number as argument

Definition at line 49 of file condition.hpp.

Constructor & Destructor Documentation

condition()

libthreadar::condition::condition

(

unsigned int

num = 1

)

constructor

Parameters

[in]

num

number of instance to create, each instance is a separated condition relying on the same mutex. First instance starts with index 0

Member Function Documentation

broadcast()

void libthreadar::condition::broadcast

(

unsigned int

instance = 0

)

awakes all threads suspended for having called wait() on the condition given in argument

Parameters

[in]

instance

broadcast threads that have been waiting on that instance

Note

broadcast() must be called between lock() and unlock(). This is only at the time unlock() is called that other threads can exit from their suspended state, by returning from their wait() call.

get_waiting_thread_count()

unsigned int libthreadar::condition::get_waiting_thread_count ( unsigned int  instance = 0 ) const

inline

return the number of thread currently waiting on that condition

Parameters

[in]

instance

the condition instance number to count the waiting thread on

Definition at line 105 of file condition.hpp.

signal()

void libthreadar::condition::signal

(

unsigned int

instance = 0

)

awakes a single thread suspended for having called wait() on the condition given in argument

Parameters

[in]

instance

the condition number to consider, only thread having called wait() with this same instance as argument are eligible to be awaken here.

Note

signal() must be called between lock() and unlock(). This is only at the time unlock() is called that another thread exits from the suspended state.

wait()

void libthreadar::condition::wait

(

unsigned int

instance = 0

)

put the calling thread on hold waiting for another thread to call signal()

Parameters

[in]

instance

the instance number to have the caller waiting on

Note

wait() must be called between lock() and unlock(). Once suspendend calling wait(), the current object is transparently unlocked, for other thread to be able to use it. The mutex is re-acquires (transparently locked) once the thread exits the wait() call it was suspended on, which occurs if another thread calls signal() with the same instance number

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

• condition.hpp