ACE_Adaptive_Lock Class Reference

An adaptive general locking class that defers the decision of lock type to run time. More...

#include <Lock.h>

Inheritance diagram for ACE_Adaptive_Lock:

Collaboration diagram for ACE_Adaptive_Lock:

Public Member Functions
virtual	~ACE_Adaptive_Lock (void)
virtual int	remove (void)
virtual int	acquire (void)
virtual int	tryacquire (void)
virtual int	release (void)
	Release the lock. Returns -1 on failure. More...
virtual int	acquire_read (void)
virtual int	acquire_write (void)
virtual int	tryacquire_read (void)
virtual int	tryacquire_write (void)
virtual int	tryacquire_write_upgrade (void)
void	dump (void) const
Public Member Functions inherited from ACE_Lock
	ACE_Lock (void)
	CE needs a default constructor here. More...
virtual	~ACE_Lock (void)
	Noop virtual destructor. More...

Protected Member Functions
	ACE_Adaptive_Lock (void)

Protected Attributes
ACE_Lock *	lock_

Detailed Description

An adaptive general locking class that defers the decision of lock type to run time.

This class, as ACE_Lock, provide a set of general locking APIs. However, it defers our decision of what kind of lock to use to the run time and delegates all locking operations to the actual lock. Users must define a constructor in their subclass to initialize lock_.

Constructor & Destructor Documentation

ACE_Adaptive_Lock::~ACE_Adaptive_Lock ( void  )

virtual

You must also override the destructor function to match with how you construct the underneath lock_.

ACE_Adaptive_Lock::ACE_Adaptive_Lock ( void  )

protected

Create and initialize create the actual lock used in the class. The default constructor simply set the lock_ to 0 (null). You must overwrite this method for this class to work.

Member Function Documentation

int ACE_Adaptive_Lock::acquire ( void  )

virtual

Block the thread until the lock is acquired. Returns -1 on failure.

Implements ACE_Lock.

int ACE_Adaptive_Lock::acquire_read ( void  )

virtual

Block until the thread acquires a read lock. If the locking mechanism doesn't support read locks then this just calls acquire(). Returns -1 on failure.

Implements ACE_Lock.

int ACE_Adaptive_Lock::acquire_write ( void  )

virtual

Block until the thread acquires a write lock. If the locking mechanism doesn't support read locks then this just calls acquire(). Returns -1 on failure.

Implements ACE_Lock.

void ACE_Adaptive_Lock::dump

(

void

)

const

int ACE_Adaptive_Lock::release ( void  )

virtual

Release the lock. Returns -1 on failure.

Implements ACE_Lock.

int ACE_Adaptive_Lock::remove ( void  )

virtual

Explicitly destroy the lock. Note that only one thread should call this method since it doesn't protect against race conditions.

Implements ACE_Lock.

int ACE_Adaptive_Lock::tryacquire ( void  )

virtual

Conditionally acquire the lock (i.e., won't block). Returns -1 on failure. If we "failed" because someone else already had the lock, errno is set to EBUSY.

Implements ACE_Lock.

int ACE_Adaptive_Lock::tryacquire_read ( void  )

virtual

Conditionally acquire a read lock. If the locking mechanism doesn't support read locks then this just calls acquire(). Returns -1 on failure. If we "failed" because someone else already had the lock, errno is set to EBUSY.

Implements ACE_Lock.

int ACE_Adaptive_Lock::tryacquire_write ( void  )

virtual

Conditionally acquire a write lock. If the locking mechanism doesn't support read locks then this just calls acquire(). Returns -1 on failure. If we "failed" because someone else already had the lock, errno is set to EBUSY.

Implements ACE_Lock.

int ACE_Adaptive_Lock::tryacquire_write_upgrade ( void  )

virtual

Conditionally try to upgrade a lock held for read to a write lock. If the locking mechanism doesn't support read locks then this just calls acquire(). Returns 0 on success, -1 on failure.

Implements ACE_Lock.

Member Data Documentation

ACE_Lock* ACE_Adaptive_Lock::lock_

protected

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

• Lock.h
• Lock.cpp