System.Net.Sockets.SocketAsyncEventArgs.FreeOverlapped C# (CSharp) Method

        private void FreeOverlapped(bool checkForShutdown)
        {
            if (!checkForShutdown || !Environment.HasShutdownStarted)
            {
                // Free the overlapped object.
                if (_ptrNativeOverlapped != null && !_ptrNativeOverlapped.IsInvalid)
                {
                    _ptrNativeOverlapped.Dispose();
                    _ptrNativeOverlapped = null;
                }

                // Free the preallocated overlapped object. This in turn will unpin
                // any pinned buffers.
                if (_preAllocatedOverlapped != null)
                {
                    _preAllocatedOverlapped.Dispose();
                    _preAllocatedOverlapped = null;

                    _pinState = PinState.None;
                    _pinnedAcceptBuffer = null;
                    _pinnedSingleBuffer = null;
                    _pinnedSingleBufferOffset = 0;
                    _pinnedSingleBufferCount = 0;
                }

                // Free any allocated GCHandles.
                if (_socketAddressGCHandle.IsAllocated)
                {
                    _socketAddressGCHandle.Free();
                    _pinnedSocketAddress = null;
                }

                if (_wsaMessageBufferGCHandle.IsAllocated)
                {
                    _wsaMessageBufferGCHandle.Free();
                    _ptrWSAMessageBuffer = IntPtr.Zero;
                }

                if (_wsaRecvMsgWSABufferArrayGCHandle.IsAllocated)
                {
                    _wsaRecvMsgWSABufferArrayGCHandle.Free();
                    _ptrWSARecvMsgWSABufferArray = IntPtr.Zero;
                }

                if (_controlBufferGCHandle.IsAllocated)
                {
                    _controlBufferGCHandle.Free();
                    _ptrControlBuffer = IntPtr.Zero;
                }
            }
        }