/// <summary>
/// Process FSEARCH instruction (CC2).
/// <para>
/// C-APDU: <code>00 B0 {P1-P2: offset} 04</code>
/// </para>
/// <para>
/// R-APDU when an EF is selected: <code>{offset} {number of word in current EF} {looked-up word}</code>
/// </para>
/// <para>
/// R-APDU when no EF is selected: <code>{offset} {number of word in current DF} {looked-up word}</code>
/// </para>
/// </summary>
/// <param name="apdu"></param>
/// <returns></returns>
private IFakeCardFeedback ProcessFSearch(CommandAPDU apdu)
{
// get offset
byte[] buffer = apdu.GetBuffer();
short offset = Util.getShort(buffer, JavaCard.ISO7816.OFFSET_P1); // in WORDS
// get le
short le = apdu.SetOutgoing(); // in BYTES
if (le != 0)
{
ISOException.throwIt(JavaCard.ISO7816.SW_WRONG_LENGTH);
}
short wordCount;
short offsetFound = offset;
// check that there is a current EF
if (_currentEF != null)
{
wordCount = (short)(_currentEF.GetLength() - _currentEF.GetHeaderSize());
while (!(_currentEF.IsAvailable(offsetFound, 1) || offsetFound == wordCount))
{
offsetFound++;
}
}
else
{
wordCount = (short)(_currentDF.GetLength() - _currentDF.GetHeaderSize());
while (!(_currentDF.IsAvailable(offsetFound, 1) || offsetFound == wordCount))
{
offsetFound++;
}
}
// check that there is still some empty space
if (offsetFound == wordCount)
{
ISOException.throwIt(Constants.SW_DATA_NOT_FOUND);
}
// copy answer in buffer
Util.setShort(buffer, 0, offsetFound);
Util.setShort(buffer, 2, wordCount);
Util.arrayFillNonAtomic(buffer, 4, 4, (byte)MemoryState.Free);
// and send it!
return(apdu.SetOutgoingAndSend(0, 8));
}
