【线程池】

参考资料

https://msdn.microsoft.com/en-us/library/windows/desktop/ms684841(v=vs.85).aspx

https://msdn.microsoft.com/en-us/library/windows/desktop/ms686353(v=vs.85).aspx

#include <windows.h>
#include <tchar.h>
#include <stdio.h>

//
// Thread pool wait callback function template
//
VOID
CALLBACK
MyWaitCallback(
PTP_CALLBACK_INSTANCE Instance,
PVOID                 Parameter,
PTP_WAIT              Wait,
TP_WAIT_RESULT        WaitResult
)
{
    // Instance, Parameter, Wait, and WaitResult not used in this example.
    UNREFERENCED_PARAMETER(Instance);
    UNREFERENCED_PARAMETER(Parameter);
    UNREFERENCED_PARAMETER(Wait);
    UNREFERENCED_PARAMETER(WaitResult);

    //
    // Do something when the wait is over.
    //
    _tprintf(_T("MyWaitCallback: wait is over.\n"));
}

//
// Thread pool timer callback function template
//
VOID
CALLBACK
MyTimerCallback(
PTP_CALLBACK_INSTANCE Instance,
PVOID                 Parameter,
PTP_TIMER             Timer
)
{
    // Instance, Parameter, and Timer not used in this example.
    UNREFERENCED_PARAMETER(Instance);
    UNREFERENCED_PARAMETER(Parameter);
    UNREFERENCED_PARAMETER(Timer);

    //
    // Do something when the timer fires.
    //
    _tprintf(_T("MyTimerCallback: timer has fired.\n"));

}

//
// This is the thread pool work callback function.
//
VOID
CALLBACK
MyWorkCallback(
PTP_CALLBACK_INSTANCE Instance,
PVOID                 Parameter,
PTP_WORK              Work
)
{
    // Instance, Parameter, and Work not used in this example.
    UNREFERENCED_PARAMETER(Instance);
    UNREFERENCED_PARAMETER(Parameter);
    UNREFERENCED_PARAMETER(Work);

    BOOL bRet = FALSE;

    //
    // Do something when the work callback is invoked.
    //
    {
        _tprintf(_T("MyWorkCallback: Task performed.\n"));
    }

    return;
}

VOID
DemoCleanupPersistentWorkTimer()
{
    BOOL bRet = FALSE;
    PTP_WORK work = NULL;
    PTP_TIMER timer = NULL;
    PTP_POOL pool = NULL;
    PTP_WORK_CALLBACK workcallback = MyWorkCallback;
    PTP_TIMER_CALLBACK timercallback = MyTimerCallback;
    TP_CALLBACK_ENVIRON CallBackEnviron;
    PTP_CLEANUP_GROUP cleanupgroup = NULL;
    FILETIME FileDueTime;
    ULARGE_INTEGER ulDueTime;
    UINT rollback = 0;

    InitializeThreadpoolEnvironment(&CallBackEnviron);

    //
    // Create a custom, dedicated thread pool.
    //
    pool = CreateThreadpool(NULL);

    if (NULL == pool) {
        _tprintf(_T("CreateThreadpool failed. LastError: %u\n"),
            GetLastError());
        goto main_cleanup;
    }

    rollback = 1; // pool creation succeeded

    //
    // The thread pool is made persistent simply by setting
    // both the minimum and maximum threads to 1.
    //
    SetThreadpoolThreadMaximum(pool, 1);

    bRet = SetThreadpoolThreadMinimum(pool, 1);

    if (FALSE == bRet) {
        _tprintf(_T("SetThreadpoolThreadMinimum failed. LastError: %u\n"),
            GetLastError());
        goto main_cleanup;
    }

    //
    // Create a cleanup group for this thread pool.
    //
    cleanupgroup = CreateThreadpoolCleanupGroup();

    if (NULL == cleanupgroup) {
        _tprintf(_T("CreateThreadpoolCleanupGroup failed. LastError: %u\n"),
            GetLastError());
        goto main_cleanup;
    }

    rollback = 2;  // Cleanup group creation succeeded

    //
    // Associate the callback environment with our thread pool.
    //
    SetThreadpoolCallbackPool(&CallBackEnviron, pool);

    //
    // Associate the cleanup group with our thread pool.
    // Objects created with the same callback environment
    // as the cleanup group become members of the cleanup group.
    //
    SetThreadpoolCallbackCleanupGroup(&CallBackEnviron,
        cleanupgroup,
        NULL);

    //
    // Create work with the callback environment.
    //
    work = CreateThreadpoolWork(workcallback,
        NULL,
        &CallBackEnviron);

    if (NULL == work) {
        _tprintf(_T("CreateThreadpoolWork failed. LastError: %u\n"),
            GetLastError());
        goto main_cleanup;
    }

    rollback = 3;  // Creation of work succeeded

    //
    // Submit the work to the pool. Because this was a pre-allocated
    // work item (using CreateThreadpoolWork), it is guaranteed to execute.
    //
    SubmitThreadpoolWork(work);

    //
    // Create a timer with the same callback environment.
    //
    timer = CreateThreadpoolTimer(timercallback,
        NULL,
        &CallBackEnviron);

    if (NULL == timer) {
        _tprintf(_T("CreateThreadpoolTimer failed. LastError: %u\n"),
            GetLastError());
        goto main_cleanup;
    }

    rollback = 4;  // Timer creation succeeded

    //
    // Set the timer to fire in one second.
    //
    ulDueTime.QuadPart = (ULONGLONG)-(1 * 10 * 1000 * 1000);
    FileDueTime.dwHighDateTime = ulDueTime.HighPart;
    FileDueTime.dwLowDateTime = ulDueTime.LowPart;

    SetThreadpoolTimer(timer,
        &FileDueTime,
        0,
        0);

    //
    // Delay for the timer to be fired
    //
    Sleep(1500);

    //
    // Wait for all callbacks to finish.
    // CloseThreadpoolCleanupGroupMembers also releases objects
    // that are members of the cleanup group, so it is not necessary
    // to call close functions on individual objects
    // after calling CloseThreadpoolCleanupGroupMembers.
    //
    CloseThreadpoolCleanupGroupMembers(cleanupgroup,
        FALSE,
        NULL);

    //
    // Already cleaned up the work item with the
    // CloseThreadpoolCleanupGroupMembers, so set rollback to 2.
    //
    rollback = 2;
    goto main_cleanup;

main_cleanup:
    //
    // Clean up any individual pieces manually
    // Notice the fall-through structure of the switch.
    // Clean up in reverse order.
    //

    switch (rollback) {
    case 4:
    case 3:
        // Clean up the cleanup group members.
        CloseThreadpoolCleanupGroupMembers(cleanupgroup,
            FALSE, NULL);
    case 2:
        // Clean up the cleanup group.
        CloseThreadpoolCleanupGroup(cleanupgroup);

    case 1:
        // Clean up the pool.
        CloseThreadpool(pool);

    default:
        break;
    }

    return;
}

VOID
DemoNewRegisterWait()
{
    PTP_WAIT Wait = NULL;
    PTP_WAIT_CALLBACK waitcallback = MyWaitCallback;
    HANDLE hEvent = NULL;
    UINT i = 0;
    UINT rollback = 0;

    //
    // Create an auto-reset event.
    //
    hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);

    if (NULL == hEvent) {
        // Error Handling
        return;
    }

    rollback = 1; // CreateEvent succeeded

    Wait = CreateThreadpoolWait(waitcallback,
        NULL,
        NULL);

    if (NULL == Wait) {
        _tprintf(_T("CreateThreadpoolWait failed. LastError: %u\n"),
            GetLastError());
        goto new_wait_cleanup;
    }

    rollback = 2; // CreateThreadpoolWait succeeded

    //
    // Need to re-register the event with the wait object
    // each time before signaling the event to trigger the wait callback.
    //
    for (i = 0; i < 5; i++) {
        SetThreadpoolWait(Wait,
            hEvent,
            NULL);

        SetEvent(hEvent);

        //
        // Delay for the waiter thread to act if necessary.
        //
        Sleep(500);

        //
        // Block here until the callback function is done executing.
        //

        WaitForThreadpoolWaitCallbacks(Wait, FALSE);
    }

new_wait_cleanup:
    switch (rollback) {
    case 2:
        // Unregister the wait by setting the event to NULL.
        SetThreadpoolWait(Wait, NULL, NULL);

        // Close the wait.
        CloseThreadpoolWait(Wait);

    case 1:
        // Close the event.
        CloseHandle(hEvent);

    default:
        break;
    }
    return;
}

int main(void)
{
    DemoNewRegisterWait();
    DemoCleanupPersistentWorkTimer();
    return 0;
}