protected void SpawnOnCardInsertedEvent(PCSCReader reader)
{
// Create the card instance for our reader
reader.ActiveCard = new PCSCCard(reader.Name);
ThreadPool.QueueUserWorkItem(delegate
{
this.RaiseOnCardInserted(reader.Name, reader.ActiveCard);
});
}
protected void SpawnOnCardRemovedEvent(PCSCReader reader)
{
if (reader.ActiveCard == null)
{
return;
}
ThreadPool.QueueUserWorkItem(delegate
{
this.RaiseOnCardRemoved(reader.Name);
});
}
private void PollingProcedure()
{
PCSCResult result;
SCardState pnpState = SCardState.Unaware;
// Set all existing readers to the 'Unaware' state to force a re-detection
foreach (var reader in myReaders.Values)
{
reader.State = SCardState.Unaware;
}
// Reader detection loop
while (true)
{
// List readers
string[] readers = ListReaders();
// Check for added readers
foreach (string r in readers)
{
if (!myReaders.ContainsKey(r))
{
lock (myReaders)
{
myReaders.Add(r, new PCSCReader(r));
}
SpawnOnReaderInsertedEvent(r);
}
}
// Check for removed readers
List <string> removed = new List <string>();
foreach (string r in myReaders.Keys)
{
if (!readers.Contains(r))
{
removed.Add(r);
}
}
foreach (string r in removed)
{
SpawnOnReaderRemovedEvent(r);
lock (myReaders)
{
myReaders.Remove(r);
}
}
// Create our reader states, including 1 for the PnP notification reader
SCARD_READERSTATE[] readerStates = new SCARD_READERSTATE[myReaders.Count + 1];
readerStates[0].szReader = PnPDetectorReader;
readerStates[0].dwCurrentState = pnpState;
for (int i = 0; i < myReaders.Count; i++)
{
PCSCReader r = myReaders.ElementAt(i).Value;
readerStates[i + 1].szReader = r.Name;
readerStates[i + 1].dwCurrentState = r.State;
}
// Reader state detection loop
while (true)
{
// Call the suspend wait event. If it is cleared, we will hold here
mySuspendEvent.WaitOne();
// First, check for a thread abort request
if (myThreadAbortRequested == true)
{
return;
}
// Wait for a status change
result = NativeMethods.SCardGetStatusChange(myContext, PollingInterval, readerStates, readerStates.Length);
// Was it a timeout? If so, just continue to the next iteration of the loop
if (PCSCResult.Timeout == result)
{
continue;
}
// Was an abort requested? If so return
if (PCSCResult.Canceled == result)
{
return;
}
// Was there another error? If so restart the loop
if (PCSCResult.None != result)
{
Debug.WriteLine($"PCSC> Error: {result}");
continue;
}
;
// Loop through each reader (skipping the PnP)
for (int i = 1; i < readerStates.Length; i++)
{
// Mask off any changes
SCardState changes = (readerStates[i].dwEventState ^ readerStates[i].dwCurrentState);
// Was a card inserted?
if ((SCardState.Present & changes & readerStates[i].dwEventState) != 0x00)
{
// Ignore cards with the MUTE flag set
if ((readerStates[i].dwEventState & SCardState.Mute) == 0)
{
lock (myReaders)
{
myReaders[readerStates[i].szReader].State |= SCardState.Present;
}
SpawnOnCardInsertedEvent(myReaders[readerStates[i].szReader]);
}
}
// Was a card removed?
if ((SCardState.Present & changes & ~readerStates[i].dwEventState) != 0x00)
{
lock (myReaders)
{
myReaders[readerStates[i].szReader].State &= ~SCardState.Present;
}
SpawnOnCardRemovedEvent(myReaders[readerStates[i].szReader]);
}
// Reset our reader polling state
readerStates[i].dwCurrentState = readerStates[i].dwEventState;
}
// Has a reader been inserted or removed? If so, break to the reader detection loop
pnpState = readerStates[0].dwEventState;
if ((readerStates[0].dwEventState & SCardState.Changed) != 0x00)
{
break;
}
readerStates[0].dwCurrentState = readerStates[0].dwEventState;
// This is where we notify the Start() method that we have run at least once
myRunOnceEvent.Set();
}
} // reader detection while
}
