/// <summary>
/// Wraps the PCSC function
/// LONG SCardReleaseContext(
/// IN SCARDCONTEXT hContext
/// );
/// </summary>
public void ReleaseContext()
{
if (PCSC.SCardIsValidContext(context) == PCSC.SCARD_S_SUCCESS)
{
lastError = PCSC.SCardReleaseContext(context);
ThrowSmartcardException("SCardReleaseContext", lastError);
context = IntPtr.Zero;
}
}
/// <summary>
/// Wraps the PCSC function
/// LONG SCardReleaseContext(
/// IN SCARDCONTEXT hContext
/// );
/// </summary>
private static void ReleaseContext(IntPtr hContext)
{
if (PCSC.SCardIsValidContext(hContext) == PCSC.SCARD_S_SUCCESS)
{
int lastError = PCSC.SCardReleaseContext(hContext);
ThrowSmartcardException("SCardReleaseContext", lastError);
//Marshal.FreeHGlobal(hContext);
hContext = IntPtr.Zero;
}
}
/// <summary>
/// This function must implement a card detection mechanism.
///
/// When card insertion is detected, it must call the method CardInserted()
/// When card removal is detected, it must call the method CardRemoved()
///
/// </summary>
protected override void RunCardDetection(string reader)
{
bool bFirstLoop = true;
IntPtr hContext = IntPtr.Zero; // Local context
IntPtr phContext;
phContext = Marshal.AllocHGlobal(Marshal.SizeOf(hContext));
if (PCSC.SCardEstablishContext((uint)SCOPE.User, IntPtr.Zero, IntPtr.Zero, phContext) == 0)
{
hContext = Marshal.ReadIntPtr(phContext);
Marshal.FreeHGlobal(phContext);
UInt32 nbReaders = 1;
PCSC.SCard_ReaderState[] readerState = new PCSC.SCard_ReaderState[nbReaders];
readerState[0].CurrentState = (UInt32)PCSC.CARD_STATE.UNAWARE;
readerState[0].Reader = reader;
UInt32 eventState;
UInt32 currentState = readerState[0].CurrentState;
// Card detection loop
do
{
if (PCSC.SCardGetStatusChange(hContext, WAIT_TIME
, readerState, nbReaders) == 0)
{
eventState = readerState[0].EventState;
currentState = readerState[0].CurrentState;
if (bFirstLoop)
{
// Check if a card is already inserted
if ((eventState & (uint)PCSC.CARD_STATE.PRESENT) == (uint)PCSC.CARD_STATE.PRESENT)
{
CardInserted(reader);
}
}
else if (((eventState & (uint)PCSC.CARD_STATE.CHANGED) == (uint)PCSC.CARD_STATE.CHANGED) && !bFirstLoop)
{
// State has changed
if ((eventState & (uint)PCSC.CARD_STATE.EMPTY) == (uint)PCSC.CARD_STATE.EMPTY)
{
// There is no card, card has been removed -> Fire CardRemoved event
CardRemoved((string)reader);
}
if (((eventState & (uint)PCSC.CARD_STATE.PRESENT) == (uint)PCSC.CARD_STATE.PRESENT) &&
((eventState & (uint)PCSC.CARD_STATE.PRESENT) != (currentState & (uint)PCSC.CARD_STATE.PRESENT)))
{
// There is a card in the reader -> Fire CardInserted event
CardInserted(reader);
}
if ((eventState & (uint)PCSC.CARD_STATE.ATRMATCH) == (uint)PCSC.CARD_STATE.ATRMATCH)
{
// There is a card in the reader and it matches the ATR we were expecting-> Fire CardInserted event
CardInserted(reader);
}
}
// The current stateis now the event state
readerState[0].CurrentState = eventState;
bFirstLoop = false;
}
Thread.SpinWait(50000);
if (cancellationToken.IsCancellationRequested)
{
break;
}
}while (true); // Exit on request
}
else
{
Marshal.FreeHGlobal(phContext);
throw new Exception("PC/SC error");
}
PCSC.SCardReleaseContext(hContext);
cancellationToken.ThrowIfCancellationRequested();
}
