INTRODUCTION
I am learning how to use Smart Card API in order to obtain card number once it gets inserted into reader.
So far I have managed to create a working application that runs (as far as I can see) without errors.
PROBLEM
During debugging I see various First chance exceptions, but every Smart Card API returns
SCARD_S_SUCCESS
and program never crashes nor exhibits any other erroneous behavior.
RELEVANT INFORMATION
- I am using Visual Studio C++ 2013
- Operating system is Windows 8.1
- Reader used is ACR122U[^]
- MVCE that reproduces the problem:
#include <Windows.h>
#include <iostream>
#include <iomanip>
#include <winscard.h>
#pragma comment(lib, "Winscard.lib")
void f() {
LPSTR s = NULL;
if (::FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, ::GetLastError(),
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), s, 0, NULL))
{
if (NULL != s)
{
std::cout << s << std::endl;
::LocalFree(s);
}
}
}
const char* error_code_to_text(LONG error_code) {
switch (error_code)
{
case SCARD_S_SUCCESS:
return "SCARD_S_SUCCESS";
case ERROR_BROKEN_PIPE:
return "ERROR_BROKEN_PIPE";
case SCARD_E_BAD_SEEK:
return "SCARD_E_BAD_SEEK";
case SCARD_E_CANCELLED:
return "SCARD_E_CANCELLED";
case SCARD_E_CANT_DISPOSE:
return "SCARD_E_CANT_DISPOSE";
case SCARD_E_CARD_UNSUPPORTED:
return "SCARD_E_CARD_UNSUPPORTED";
case SCARD_E_CERTIFICATE_UNAVAILABLE:
return "SCARD_E_CERTIFICATE_UNAVAILABLE";
case SCARD_E_COMM_DATA_LOST:
return "SCARD_E_COMM_DATA_LOST";
case SCARD_E_DIR_NOT_FOUND:
return "SCARD_E_DIR_NOT_FOUND";
case SCARD_E_DUPLICATE_READER:
return "SCARD_E_DUPLICATE_READER";
case SCARD_E_FILE_NOT_FOUND:
return "SCARD_E_FILE_NOT_FOUND";
case SCARD_E_ICC_CREATEORDER:
return "SCARD_E_ICC_CREATEORDER";
case SCARD_E_ICC_INSTALLATION:
return "SCARD_E_ICC_INSTALLATION";
case SCARD_E_INSUFFICIENT_BUFFER:
return "SCARD_E_INSUFFICIENT_BUFFER";
case SCARD_E_INVALID_ATR:
return "SCARD_E_INVALID_ATR";
case SCARD_E_INVALID_CHV:
return "SCARD_E_INVALID_CHV";
case SCARD_E_INVALID_HANDLE:
return "SCARD_E_INVALID_HANDLE";
case SCARD_E_INVALID_PARAMETER:
return "SCARD_E_INVALID_PARAMETER";
case SCARD_E_INVALID_TARGET:
return "SCARD_E_INVALID_TARGET";
case SCARD_E_INVALID_VALUE:
return "SCARD_E_INVALID_VALUE";
case SCARD_E_NO_ACCESS:
return "SCARD_E_NO_ACCESS";
case SCARD_E_NO_DIR:
return "SCARD_E_NO_DIR";
case SCARD_E_NO_FILE:
return "SCARD_E_NO_FILE";
case SCARD_E_NO_KEY_CONTAINER:
return "SCARD_E_NO_KEY_CONTAINER";
case SCARD_E_NO_MEMORY:
return "SCARD_E_NO_MEMORY";
case SCARD_E_NO_PIN_CACHE:
return "SCARD_E_NO_PIN_CACHE";
case SCARD_E_NO_READERS_AVAILABLE:
return "SCARD_E_NO_READERS_AVAILABLE";
case SCARD_E_NO_SERVICE:
return "SCARD_E_NO_SERVICE";
case SCARD_E_NO_SMARTCARD:
return "SCARD_E_NO_SMARTCARD";
case SCARD_E_NO_SUCH_CERTIFICATE:
return "SCARD_E_NO_SUCH_CERTIFICATE";
case SCARD_E_NOT_READY:
return "SCARD_E_NOT_READY";
case SCARD_E_NOT_TRANSACTED:
return "SCARD_E_NOT_TRANSACTED";
case SCARD_E_PCI_TOO_SMALL:
return "SCARD_E_PCI_TOO_SMALL";
case SCARD_E_PIN_CACHE_EXPIRED:
return "SCARD_E_PIN_CACHE_EXPIRED";
case SCARD_E_PROTO_MISMATCH:
return "SCARD_E_PROTO_MISMATCH";
case SCARD_E_READ_ONLY_CARD:
return "SCARD_E_READ_ONLY_CARD";
case SCARD_E_READER_UNAVAILABLE:
return "SCARD_E_READER_UNAVAILABLE";
case SCARD_E_READER_UNSUPPORTED:
return "SCARD_E_READER_UNSUPPORTED";
case SCARD_E_SERVER_TOO_BUSY:
return "SCARD_E_SERVER_TOO_BUSY";
case SCARD_E_SERVICE_STOPPED:
return "SCARD_E_SERVICE_STOPPED";
case SCARD_E_SHARING_VIOLATION:
return "SCARD_E_SHARING_VIOLATION";
case SCARD_E_SYSTEM_CANCELLED:
return "SCARD_E_SYSTEM_CANCELLED";
case SCARD_E_TIMEOUT:
return "SCARD_E_TIMEOUT";
case SCARD_E_UNEXPECTED:
return "SCARD_E_UNEXPECTED";
case SCARD_E_UNKNOWN_CARD:
return "SCARD_E_UNKNOWN_CARD";
case SCARD_E_UNKNOWN_READER:
return "SCARD_E_UNKNOWN_READER";
case SCARD_E_UNKNOWN_RES_MNG:
return "SCARD_E_UNKNOWN_RES_MNG";
case SCARD_E_UNSUPPORTED_FEATURE:
return "SCARD_E_UNSUPPORTED_FEATURE";
case SCARD_E_WRITE_TOO_MANY:
return "SCARD_E_WRITE_TOO_MANY";
case SCARD_F_COMM_ERROR:
return "SCARD_F_COMM_ERROR";
case SCARD_F_INTERNAL_ERROR:
return "SCARD_F_INTERNAL_ERROR";
case SCARD_F_UNKNOWN_ERROR:
return "SCARD_F_UNKNOWN_ERROR";
case SCARD_F_WAITED_TOO_LONG:
return "SCARD_F_WAITED_TOO_LONG";
case SCARD_P_SHUTDOWN:
return "SCARD_P_SHUTDOWN";
case SCARD_W_CANCELLED_BY_USER:
return "SCARD_W_CANCELLED_BY_USER";
case SCARD_W_CACHE_ITEM_NOT_FOUND:
return "SCARD_W_CACHE_ITEM_NOT_FOUND";
case SCARD_W_CACHE_ITEM_STALE:
return "SCARD_W_CACHE_ITEM_STALE";
case SCARD_W_CACHE_ITEM_TOO_BIG:
return "SCARD_W_CACHE_ITEM_TOO_BIG";
case SCARD_W_CARD_NOT_AUTHENTICATED:
return "SCARD_W_CARD_NOT_AUTHENTICATED";
case SCARD_W_CHV_BLOCKED:
return "SCARD_W_CHV_BLOCKED";
case SCARD_W_EOF:
return "SCARD_W_EOF";
case SCARD_W_REMOVED_CARD:
return "SCARD_W_REMOVED_CARD";
case SCARD_W_RESET_CARD:
return "SCARD_W_RESET_CARD";
case SCARD_W_SECURITY_VIOLATION:
return "SCARD_W_SECURITY_VIOLATION";
case SCARD_W_UNPOWERED_CARD:
return "SCARD_W_UNPOWERED_CARD";
case SCARD_W_UNRESPONSIVE_CARD:
return "SCARD_W_UNRESPONSIVE_CARD";
case SCARD_W_UNSUPPORTED_CARD:
return "SCARD_W_UNSUPPORTED_CARD";
case SCARD_W_WRONG_CHV:
return "SCARD_W_WRONG_CHV";
default:
return "Unknown error code";
}
}
DWORD WINAPI SmartCardListener(LPVOID arg)
{
std::cout << "SmartCardListener Thread ID = "
<< std::setw(8) << std::setfill('0') << std::hex
<< ::GetCurrentThreadId() << std::endl;
SCARDCONTEXT c = *reinterpret_cast<SCARDCONTEXT *>(arg);
LPTSTR r = NULL;
DWORD cch = SCARD_AUTOALLOCATE;
LONG l = SCardListReaders(c, NULL, (LPTSTR)&r, &cch);
if (SCARD_S_SUCCESS != l)
{
std::cout << "SCardListReaders failed with error code: "
<< error_code_to_text(l) << std::endl;
return 1;
}
SCARD_READERSTATE rs = {};
rs.dwCurrentState = SCARD_STATE_UNAWARE;
rs.szReader = &r[0];
do
{
l = ::SCardGetStatusChange(c, INFINITE, &rs, 1);
rs.dwCurrentState = rs.dwEventState;
}
while (l == SCARD_S_SUCCESS);
if (SCARD_E_CANCELLED != l)
std::cout << "SCardGetStatusChange failed with error code: "
<< error_code_to_text(l) << std::endl;
l = SCardFreeMemory(c, r);
if (SCARD_S_SUCCESS != l)
{
std::cout << "SCardFreeMemory failed with error code: "
<< error_code_to_text(l) << std::endl;
return 1;
}
return 0;
}
int main()
{
std::cout << "Main Thread ID = "
<< std::setw(8)
<< std::setfill('0')
<< std::hex
<< ::GetCurrentThreadId()
<< std::endl;
SCARDCONTEXT c;
LONG l = ::SCardEstablishContext(SCARD_SCOPE_USER, NULL, NULL, &c);
if (SCARD_S_SUCCESS != l)
{
std::cout << "SCardEstablishContext failed with error code: "
<< error_code_to_text(l)
<< std::endl;
return -1;
}
HANDLE t = ::CreateThread(NULL, 0, SmartCardListener, &c, 0, 0);
if (NULL == t)
{
std::cout << "CreateThread failed:" << std::endl;
f();
::SCardReleaseContext(c);
return 0;
}
std::cout << "Press ENTER to quit..." << std::endl;
std::cin.get();
l = ::SCardCancel(c);
if (SCARD_S_SUCCESS != l)
std::cout << "SCardCancel failed with error code: "
<< error_code_to_text(l)
<< std::endl;
DWORD d = ::WaitForSingleObject(t, INFINITE);
switch (d)
{
case WAIT_OBJECT_0:
std::cout << "Graceful exit" << std::endl;
break;
case WAIT_TIMEOUT:
std::cout << "Timeout" << std::endl;
break;
case WAIT_FAILED:
std::cout << "Wait failed: " << std::endl;
f();
::TerminateThread(t, 1); break;
default:
std::cout << "Unknown error" << std::endl;
::TerminateThread(t, 1); break;
}
::CloseHandle(t);
l = ::SCardReleaseContext(c);
if (SCARD_S_SUCCESS != l)
{
std::cout << "Failed to release context" << std::endl;
}
return 0;
}
I have tested 2 cases:
- Reader is not plugged in
- Reader is plugged in, and program is terminated by pressing ENTER as instructed
When not plugged in, app properly displays error message, thread exits cleanly, but I get following relevant content from the Output window:
First-chance exception at 0x76DD5EF8 (KernelBase.dll) in SO_Demo.exe: 0x8010002E: Cannot find a smart card reader.
First-chance exception at 0x76DD5EF8 (KernelBase.dll) in SO_Demo.exe: 0x0000071A: The remote procedure call was canceled, or if a call time-out was specified, the call timed out.
First-chance exception at 0x76DD5EF8 in SO_Demo.exe: Microsoft C++ exception: unsigned long at memory location 0x0142F970.
First-chance exception at 0x76DD5EF8 in SO_Demo.exe: Microsoft C++ exception: [rethrow] at memory location 0x00000000.
The thread 0x120c has exited with code 1 (0x1).
Thread 0x120C is the SmartCardListener
from the demo.
When reader is plugged in, and I press
ENTER, code shuts down cleanly.
Notice the relevant portion of the Output window content:
First-chance exception at 0x76DD5EF8 (KernelBase.dll) in SO_Demo.exe: 0x80100002: The action was cancelled by an SCardCancel request.
First-chance exception at 0x76DD5EF8 (KernelBase.dll) in SO_Demo.exe: 0x0000071A: The remote procedure call was canceled, or if a call time-out was specified, the call timed out.
First-chance exception at 0x76DD5EF8 in SO_Demo.exe: Microsoft C++ exception: unsigned long at memory location 0x0139F5E8.
First-chance exception at 0x76DD5EF8 in SO_Demo.exe: Microsoft C++ exception: unsigned long at memory location 0x0139F6D0.
The thread 0x1d2c has exited with code 0 (0x0).
Thread ox1D2C is the SmartCardListener
from the demo.
QUESTION
- Is my conclusion correct ? Was this just a false alarm ?
- If my conclusion is false, can you instruct me on how to solve this problem ?
What I have tried:
In both cases I did the following:
- Went to Visual Studio menu Debug -> Exceptions and checked Thrown checkbox
- Walked the code in Debug mode by pressing F10
- Each time it would break at Smart Card API
- A popup "First chance exception..." would come out
- I would choose Continue (Break and Cancel were also offered)
- Popup would appear again, and I would choose again Continue
Again, program would shut down cleanly, inspection of the return values showed
SCARD_S_SUCCESS
or expected value (
SCARD_E_CANCELLED
when
SCardCancel
was called or
SCARD_E_NO_READERS_AVAILABLE
when reader was not present).
I have also noticed that the exception always happens on memory location 0x76DD5EF8 but I do not know how to use this information to help me solve the problem.
I have tried Googling for a solution and the only useful thing I found was
this[
^].
Reading through the link provided in the accepted answer, I came to the conclusion that these exceptions might be a false alarm.