RFAddReader: more correctly detect duplicate readers

To detect a duplicate reader, checking the reader name and port is,
sometimes, not enough.

The problem was when two readers are removed and re-inserted immediately.
One of the 2 readers may not yet be completely removed (from pcscd point
of view) when it is asked to insert it again.

Fixes #20
"Reader not detected when disconnecting / connecting usb hub"
#20

src/readerfactory.c

@@ -223,7 +223,7 @@ LONG RFAddReader(const char *readerNameLong, int port, const char *library,
  readerName[MAX_READERNAME - sizeof(" 00 00")] = '\0';
  }
 
- /* Same name, same port - duplicate reader cannot be used */
+ /* Same name, same port, same device - duplicate reader cannot be used */
  if (dwNumReadersContexts != 0)
  {
  for (i = 0; i < PCSCLITE_MAX_READERS_CONTEXTS; i++)
@@ -240,8 +240,9 @@ LONG RFAddReader(const char *readerNameLong, int port, const char *library,
  tmplen = strlen(lpcStripReader);
  lpcStripReader[tmplen - 6] = 0;
 
- if ((strcmp(readerName, lpcStripReader) == 0) &&
- (port == sReadersContexts[i]->port))
+ if ((strcmp(readerName, lpcStripReader) == 0)
+ && (port == sReadersContexts[i]->port)
+ && (strcmp(device, sReadersContexts[i]->device) == 0))
  {
  Log1(PCSC_LOG_ERROR, "Duplicate reader found.");
  return SCARD_E_DUPLICATE_READER;