XbmcThreads::CountingLockable< L > Class Template Reference

#include <Lockables.h>

Public Member Functions
	CountingLockable ()=default
void	lock ()
bool	try_lock ()
void	unlock ()
unsigned int	exit (unsigned int leave=0)
void	restore (unsigned int restoreCount)
L &	get_underlying ()

Protected Attributes
L	mutex
unsigned int	count = 0

Friends
class	ConditionVariable

Detailed Description

template<class L>
class XbmcThreads::CountingLockable< L >

This template will take any implementation of the "Lockable" concept and allow it to be used as an "Exitable Lockable."

Something that implements the "Lockable concept" simply means that it has the three methods:

lock(); try_lock(); unlock();

"Exitable" specifically means that, no matter how deep the recursion on the mutex/critical section, we can exit from it and then restore the state.

This requires us to extend the Lockable so that we can keep track of the number of locks that have been recursively acquired so that we can undo it, and then restore that (See class CSingleExit).

All xbmc code expects Lockables to be recursive.

Constructor & Destructor Documentation

CountingLockable()

template<class L >

XbmcThreads::CountingLockable< L >::CountingLockable ( )

inlinedefault

Member Function Documentation

exit()

template<class L >

unsigned int XbmcThreads::CountingLockable< L >::exit ( unsigned int  leave = 0 )

inline

This implements the "exitable" behavior mentioned above.

This can be used to ALMOST exit, but not quite, by passing the number of locks to leave. This is used in the windows ConditionVariable which requires that the lock be entered only once, and so it backs out ALMOST all the way, but leaves one still there.

get_underlying()

template<class L >

L & XbmcThreads::CountingLockable< L >::get_underlying ( )

inline

Some implementations (see pthreads) require access to the underlying CCriticalSection, which is also implementation specific. This provides access to it through the same method on the guard classes UniqueLock, and SharedLock.

There really should be no need for the users of the threading library to call this method.

lock()

template<class L >

void XbmcThreads::CountingLockable< L >::lock ( )

inline

restore()

template<class L >

void XbmcThreads::CountingLockable< L >::restore ( unsigned int  restoreCount )

inline

Restore a previous exit to the provided level.

try_lock()

template<class L >

bool XbmcThreads::CountingLockable< L >::try_lock ( )

inline

unlock()

template<class L >

void XbmcThreads::CountingLockable< L >::unlock ( )

inline

Friends And Related Function Documentation

ConditionVariable

template<class L >

friend class ConditionVariable

friend

Member Data Documentation

count

template<class L >

unsigned int XbmcThreads::CountingLockable< L >::count = 0

protected

mutex

template<class L >

L XbmcThreads::CountingLockable< L >::mutex

protected

---

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

• Lockables.h