/// <summary>
/// This method borrows a lock from the lowest layer (lock store).
/// </summary>
/// <param name="key">Generic key against which the lock is maintained</param>
/// <returns></returns>
private SlimLockWrapper BorrowLockObject(TKey key, bool createNew)
{
SlimLockWrapper retInstance = null;
lock (_keyLockTable){
if (_keyLockTable.ContainsKey(key))
{
retInstance = _keyLockTable[key];
}
if (retInstance == null && !createNew)
{
return(null);
}
if (retInstance == null)
{
retInstance = _keyLockTable[key] = new SlimLockWrapper(_policy);
}
else if (retInstance.MarkedDeleted)
{
retInstance = _keyLockTable[key] = new SlimLockWrapper(_policy);
}
retInstance.IncrementRef();
return(retInstance);
}
}
private void GetLock(TKey key) //, LockMode lockMode)
{
SlimLockWrapper slimlock = BorrowLockObject(key, true);
slimlock.GetLock();
}
private SlimLockWrapper GetLockObject(TKey key)
{
SlimLockWrapper retInstance = null;
lock (_keyLockTable)
{
if (_keyLockTable.ContainsKey(key))
{
retInstance = _keyLockTable[key];
}
return(retInstance);
}
}
private void ReleaseLock(TKey key)//, LockMode lockMode)
{
SlimLockWrapper lockObject = GetLockObject(key);
if(lockObject == null)
return;
lockObject.ReleaseLock();
ReturnLockObject(key, lockObject);
}
private void GetLock(TKey key, LockMode lockMode)
{
SlimLockWrapper slimlock = BorrowLockObject(key, true);
switch (lockMode)
{
case LockMode.Reader:
slimlock.GetReaderLock();
return;
case LockMode.Write:
slimlock.GetWriterLock();
return;
}
}
/// <summary>
/// This method returns a lock object to the lowest layer (lock store).
/// </summary>
/// <param name="key">Generic key against which the lock is maintained.</param>
/// <param name="lockObject">The lock value stored.</param>
private void ReturnLockObject(TKey key, SlimLockWrapper lockObject)
{
lock (_keyLockTable){
lockObject.DecrementRef();
if (lockObject.MarkedDeleted)
{
SlimLockWrapper outValue;
if (_keyLockTable.TryGetValue(key, out outValue) &&
lockObject == outValue)
{
_keyLockTable.Remove(key);
}
}
}
}
private void ReleaseLock(TKey key, LockMode lockMode)
{
SlimLockWrapper lockObject = GetLockObject(key);
if (lockObject == null)
{
return;
}
switch (lockMode)
{
case LockMode.Reader:
lockObject.ReleaseReaderLock();
break;
case LockMode.Write:
lockObject.ReleaseWriterLock();
break;
}
ReturnLockObject(key, lockObject);
}
/// <summary>
/// This method borrows a lock from the lowest layer (lock store).
/// </summary>
/// <param name="key">Generic key against which the lock is maintained</param>
/// <returns></returns>
private SlimLockWrapper BorrowLockObject(TKey key, bool createNew)
{
SlimLockWrapper retInstance;
lock (_keyLockTable)
{
_keyLockTable.TryGetValue(key, out retInstance);
if (retInstance == null && !createNew)
{
return null;
}
if (retInstance == null)
{
retInstance = _keyLockTable[key] = new SlimLockWrapper();//_policy);
}
else if (retInstance.MarkedDeleted){
retInstance = _keyLockTable[key] = new SlimLockWrapper();// _policy);
}
retInstance.IncrementRef();
return retInstance;
}
}
