/// <summary>
/// Releases this cached value.
/// </summary>
void IDisposable.Dispose()
{
Cache <T> .Release(this);
}
/// <summary>
/// Releases a cached value.
/// </summary>
/// <param name="cache">The cached value to release.</param>
/// <exception cref="System.ArgumentNullException">The cached value to release is null.</exception>
public static void Release(Cache <T> cache)
{
if (cache == null)
{
throw new ArgumentNullException("cache");
}
if (cache.isFree)
{
return;
}
// No need to call this method inside the lock, which might do heavy work
// there is a thread safety hole here, actually - if several different threads
// are trying to free the same cache instance, OnFreed might be called several
// times concurrently for the same cached value.
if (IsNotificationReceiver)
{
(cache.Value as ICacheNotificationReceiver).OnFreed();
}
while (true)
{
if (Interlocked.CompareExchange(ref THREAD_LOCK_TOKEN, 1, 0) == 0)
{
break;
}
}
// We now hold the lock
if (cache.isFree)
{
// Release the lock and leave - job's done already
THREAD_LOCK_TOKEN = 0;
return;
}
cache.isFree = true;
var freeValues = FreeValues;
var length = freeValues.Length;
bool added = false;
for (int i = 0; i < length; i++)
{
if (object.ReferenceEquals(freeValues[i], null))
{
freeValues[i] = cache;
added = true;
break;
}
}
if (!added && length < MaxCacheSize)
{
var newArr = new object[length * 2];
for (int i = 0; i < length; i++)
{
newArr[i] = freeValues[i];
}
newArr[length] = cache;
FreeValues = newArr;
}
// Release the lock
THREAD_LOCK_TOKEN = 0;
}
