CALockAble Class Reference

From this class other classes could be derived, which need some kind from "locking" in memory. More...

Inheritance diagram for CALockAble:

List of all members.

Public Member Functions
	CALockAble ()
virtual	~CALockAble ()
SINT32	lock ()
	Locks the lockable object by threadsafe incrementing a reference counter.
SINT32	unlock ()
	Unlocks the lockable object by threadsafe decrementing a reference counter.
Protected Member Functions
SINT32	waitForDestroy ()
	If called checks if the reference counter equals zero.
Private Attributes
CAConditionVariable	m_ConVar
	A conditional variable, which would be signaled if the rerference counter reaches zero.
UINT32	m_nLockCount
	The reference counter.

---

Detailed Description

From this class other classes could be derived, which need some kind from "locking" in memory.

Imagine for instance that thread t1 creates an object o of class c and uses it. During that a second thread t2 destroies o by calling delete o. Clearly this would be desasterous. To solve this problem cc should be derived from CALockAble. Than t1 calls o.lock() before using o and o.unlock() if t1 finsihed using o. If t2 calls delete o between the lock() / unlock() calls, it would block until all references of o are unlocked. Probablly this class is usefull for other tings, too...

---

Constructor & Destructor Documentation

CALockAble::CALockAble

(

)

References m_nLockCount.

virtual CALockAble::~CALockAble

(

)

[virtual]

---

Member Function Documentation

SINT32 CALockAble::lock

(

)

Locks the lockable object by threadsafe incrementing a reference counter.

Return values:

E_SUCCESS

References E_SUCCESS, CAMutex::lock(), m_ConVar, m_nLockCount, and CAMutex::unlock().

Referenced by CAMiddleMixChannelList::getInToOut(), CAMiddleMixChannelList::getOutToIn_intern_without_lock(), and CAFirstMixA::loop().

SINT32 CALockAble::unlock

(

)

Unlocks the lockable object by threadsafe decrementing a reference counter.

The counter would never become less than zero. Every thread, which waits in waitForDestroy() will be signaled.

Return values:

E_SUCCESS

References E_SUCCESS, CAMutex::lock(), m_ConVar, m_nLockCount, CAConditionVariable::signal(), and CAMutex::unlock().

Referenced by mm_loopReadFromMixAfter(), and mm_loopReadFromMixBefore().

SINT32 CALockAble::waitForDestroy

(

)

[protected]

If called checks if the reference counter equals zero.

If the reference counter is greater than zero, the call blocks.

Return values:

E_SUCCESS

References E_SUCCESS, CAMutex::lock(), m_ConVar, m_nLockCount, CAMutex::unlock(), and CAConditionVariable::wait().

Referenced by CASymCipher::~CASymCipher().

---

Member Data Documentation

CAConditionVariable CALockAble::m_ConVar [private]

A conditional variable, which would be signaled if the rerference counter reaches zero.

Referenced by lock(), unlock(), and waitForDestroy().

UINT32 CALockAble::m_nLockCount [private]

The reference counter.

Referenced by CALockAble(), lock(), unlock(), and waitForDestroy().