private static void free(UsbTransferQueue transferParam)
{
for (int i = 0; i < transferParam.MaxOutstandingIO; i++)
{
if (!ReferenceEquals(transferParam.mTransferHandles[i], null))
{
if (transferParam.mTransferHandles[i].InUse)
{
if (!transferParam.mTransferHandles[i].Context.IsCompleted)
{
transferParam.EndpointBase.Abort();
Thread.Sleep(1);
}
transferParam.mTransferHandles[i].InUse = false;
transferParam.mTransferHandles[i].Context.Dispose();
}
transferParam.mTransferHandles[i] = null;
}
}
transferParam.mOutstandingTransferCount = 0;
transferParam.mTransferHandleNextIndex = 0;
transferParam.mTransferHandleWaitIndex = 0;
}
private static ErrorCode transfer(UsbTransferQueue transferParam, out Handle handle)
{
handle = null;
ErrorCode ret = ErrorCode.Success;
// Submit transfers until the maximum number of outstanding transfer(s) is reached.
while (transferParam.mOutstandingTransferCount < transferParam.MaxOutstandingIO)
{
if (ReferenceEquals(transferParam.mTransferHandles[transferParam.mTransferHandleNextIndex], null))
{
handle = transferParam.mTransferHandles[transferParam.mTransferHandleNextIndex] =
new Handle(transferParam.EndpointBase.NewAsyncTransfer(), transferParam.mBuffer[transferParam.mTransferHandleNextIndex]);
// Get the next available benchmark transfer handle.
handle.Context.Fill(handle.Data, 0, handle.Data.Length, transferParam.Timeout, transferParam.IsoPacketSize);
}
else
{
// Get the next available benchmark transfer handle.
handle = transferParam.mTransferHandles[transferParam.mTransferHandleNextIndex];
}
handle.Transferred = 0;
// Submit this transfer now.
handle.Context.Reset();
ret = handle.Context.Submit();
if (ret != ErrorCode.Success)
{
goto Done;
}
// Mark this handle has InUse.
handle.InUse = true;
// When transfers ir successfully submitted, OutstandingTransferCount goes up; when
// they are completed it goes down.
//
transferParam.mOutstandingTransferCount++;
// Move TransferHandleNextIndex to the next available transfer.
IncWithRoll(ref transferParam.mTransferHandleNextIndex, transferParam.MaxOutstandingIO);
}
// If the number of outstanding transfers has reached the limit, wait for the
// oldest outstanding transfer to complete.
//
if (transferParam.mOutstandingTransferCount == transferParam.MaxOutstandingIO)
{
// TransferHandleWaitIndex is the index of the oldest outstanding transfer.
handle = transferParam.mTransferHandles[transferParam.mTransferHandleWaitIndex];
ret = handle.Context.Wait(out handle.Transferred, false);
if (ret != ErrorCode.Success)
{
goto Done;
}
// Mark this handle has no longer InUse.
handle.InUse = false;
// When transfers ir successfully submitted, OutstandingTransferCount goes up; when
// they are completed it goes down.
//
transferParam.mOutstandingTransferCount--;
// Move TransferHandleWaitIndex to the oldest outstanding transfer.
IncWithRoll(ref transferParam.mTransferHandleWaitIndex, transferParam.MaxOutstandingIO);
return(ErrorCode.Success);
}
Done:
return(ret);
}