CODEWITHSUNDEEP
c++multithreadingvisual-studio-2008crashheap-memory
Jim Fell
Jim Fell

Reputation: 14254

Application Crashes on Thread Exit - C++

My application is crashing when it exits the thread function. This is how my thread is initialized:

LPTHREAD_START_ROUTINE pThreadStart = (LPTHREAD_START_ROUTINE)NotifyWindowThreadFn;
void * pvThreadData = reinterpret_cast<void *>(_pobjSerialPort);

// Create the exit notify window thread event handle.
_hNotifyWindowThreadExitEvent = ::CreateEvent(
    NULL,                           // No security
    TRUE,                           // Create a manual-reset event object
    FALSE,                          // Initial state is non-signaled
    NULL                            // No name specified
    );

if ( _hNotifyWindowThreadExitEvent == NULL )
{
    TRACE(_T("CreateNotifyWindow : Failed to get a handle for the exit message-only window event.\r\n\tError: %d\r\n\tFile: %s\r\n\tLine: %d\r\n"), ::GetLastError(), __WFILE__, __LINE__);
    return ::GetLastError();
}

// Create the notify window thread to begin execution on its own.
_hNotifyWindowThread = ::CreateThread(
    NULL,                           // No security attributes.
    0,                              // Use default initial stack size.
    pThreadStart,                   // Function to execute in new thread.
    pvThreadData,                   // Thread parameters.
    0,                              // Use default creation settings.
    NULL                            // Thread ID is not needed.
    );

if ( _hNotifyWindowThread == NULL )
{
    TRACE(_T("CreateNotifyWindow : Failed to create handle for message-only window thread.\r\n\tError: %d\r\n\tFile: %s\r\n\tLine: %d\r\n"), ::GetLastError(), __WFILE__, __LINE__);
    return ::GetLastError();
}

This is the portion of my thread function that gets executed:

DWORD NotifyWindowThreadFn( void * pParam )
{
    static CNotifyWindow * pobjNotifyWindow = NULL;
    CSerialPort * pobjSerialPort = reinterpret_cast<CSerialPort *>(pParam);

    // Create notify window to handle surprize removal/insertion events...
    try
    {
        pobjNotifyWindow = new CNotifyWindow();
    }
    catch ( DWORD error )
    {
        return error;                // 1. PC gets here
    }
    catch ( long error )
    {
        return error;
    }
    catch ( ... )
    {
        return ERROR_CANNOT_MAKE;
    }

    /* Other stuff that is not executed due to return. */

}                                     // 2. PC then gets here

When the application crashes, Visual Studio gives me this error message:

Windows has triggered a breakpoint in CppTestConsole.exe.

This may be due to a corruption of the heap, which indicates a bug in CppTestConsole.exe or any of the DLLs it has loaded.

This may also be due to the user pressing F12 while CppTestConsole.exe has focus.

The output window may have more diagnostic information.

The output window doesn't have anything especially useful. Only...

The thread 'NotifyWindowThreadFn' (0x414) has exited with code 0 (0x0).

Then it shows that a bunch of DLLs are unloaded. When I click the Break button, the PC is at the end of _CrtIsValidHeapPointer in dbgheap.c. Does anyone have any ideas as to why my application is crashing when the thread exits? Should I not be returning directly from within a threaded function? Thanks.

Upvotes: 0

Views: 2437

Answers (3)

engf-010
engf-010

Reputation: 3929

you should declare and define you function as : DWORD WINAPI NotifyWindowThreadFn( void * pParam )

Upvotes: 1

Leo Davidson
Leo Davidson

Reputation: 6143

Try using _beginthreadex instead of CreateThread:

A thread in an executable that calls the C run-time library (CRT) should use the _beginthreadex and _endthreadex functions for thread management rather than CreateThread and ExitThread; this requires the use of the multi-threaded version of the CRT. If a thread created using CreateThread calls the CRT, the CRT may terminate the process in low-memory conditions.

Upvotes: 0

John Dibling
John Dibling

Reputation: 101466

I might be wrong, but it seems like you're trying to create a window from a worker thread. Don't do this. Windows need the message pump in order to function, and there's only one message pump in your application -- it's in the main thread.

Upvotes: 3

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