reactos/dll/win32/kernel32/thread/thread.c

/*
 * COPYRIGHT:       See COPYING in the top level directory
 * PROJECT:         ReactOS system libraries
 * FILE:            lib/kernel32/thread/thread.c
 * PURPOSE:         Thread functions
 * PROGRAMMERS:     Alex Ionescu (alex@relsoft.net)
 *                  Ariadne ( ariadne@xs4all.nl)
 *
 */

/* INCLUDES ******************************************************************/

#include <k32.h>

#define NDEBUG
#include <debug.h>

/* FIXME: NDK */
#define HIGH_PRIORITY 31
#define SXS_SUPPORT_FIXME

NTSTATUS
WINAPI
BasepNotifyCsrOfThread(IN HANDLE ThreadHandle,
                       IN PCLIENT_ID ClientId);

/* FUNCTIONS *****************************************************************/
static
LONG BaseThreadExceptionFilter(EXCEPTION_POINTERS * ExceptionInfo)
{
   LONG ExceptionDisposition = EXCEPTION_EXECUTE_HANDLER;

   if (GlobalTopLevelExceptionFilter != NULL)
   {
      _SEH2_TRY
      {
         ExceptionDisposition = GlobalTopLevelExceptionFilter(ExceptionInfo);
      }
      _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
      {
         ExceptionDisposition = UnhandledExceptionFilter(ExceptionInfo);
      }
      _SEH2_END;
   }

   return ExceptionDisposition;
}

__declspec(noreturn)
VOID
WINAPI
BaseThreadStartup(LPTHREAD_START_ROUTINE lpStartAddress,
                  LPVOID lpParameter)
{
    volatile UINT uExitCode = 0;

    /* Attempt to call the Thread Start Address */
    _SEH2_TRY
    {
        /* Get the exit code from the Thread Start */
        uExitCode = (lpStartAddress)((PVOID)lpParameter);
    }
    _SEH2_EXCEPT(BaseThreadExceptionFilter(_SEH2_GetExceptionInformation()))
    {
        /* Get the Exit code from the SEH Handler */
        uExitCode = _SEH2_GetExceptionCode();
    } _SEH2_END;

    /* Exit the Thread */
    ExitThread(uExitCode);
}

/*
 * @implemented
 */
HANDLE
WINAPI
CreateThread(LPSECURITY_ATTRIBUTES lpThreadAttributes,
             DWORD dwStackSize,
             LPTHREAD_START_ROUTINE lpStartAddress,
             LPVOID lpParameter,
             DWORD dwCreationFlags,
             LPDWORD lpThreadId)
{
    /* Act as if we're going to create a remote thread in ourselves */
    return CreateRemoteThread(NtCurrentProcess(),
                              lpThreadAttributes,
                              dwStackSize,
                              lpStartAddress,
                              lpParameter,
                              dwCreationFlags,
                              lpThreadId);
}

/*
 * @implemented
 */
HANDLE
WINAPI
CreateRemoteThread(HANDLE hProcess,
                   LPSECURITY_ATTRIBUTES lpThreadAttributes,
                   DWORD dwStackSize,
                   LPTHREAD_START_ROUTINE lpStartAddress,
                   LPVOID lpParameter,
                   DWORD dwCreationFlags,
                   LPDWORD lpThreadId)
{
    NTSTATUS Status;
    INITIAL_TEB InitialTeb;
    CONTEXT Context;
    CLIENT_ID ClientId;
    OBJECT_ATTRIBUTES LocalObjectAttributes;
    POBJECT_ATTRIBUTES ObjectAttributes;
    HANDLE hThread;
    ULONG Dummy;

    DPRINT("CreateRemoteThread: hProcess: %ld dwStackSize: %ld lpStartAddress"
            ": %p lpParameter: %lx, dwCreationFlags: %lx\n", hProcess,
            dwStackSize, lpStartAddress, lpParameter, dwCreationFlags);

    /* Clear the Context */
    RtlZeroMemory(&Context, sizeof(CONTEXT));

    /* Write PID */
    ClientId.UniqueProcess = hProcess;

    /* Create the Stack */
    Status = BasepCreateStack(hProcess,
                              dwStackSize,
                              dwCreationFlags & STACK_SIZE_PARAM_IS_A_RESERVATION ?
                              dwStackSize : 0,
                              &InitialTeb);
    if(!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return NULL;
    }

    /* Create Initial Context */
    BasepInitializeContext(&Context,
                           lpParameter,
                           lpStartAddress,
                           InitialTeb.StackBase,
                           1);

    /* initialize the attributes for the thread object */
    ObjectAttributes = BasepConvertObjectAttributes(&LocalObjectAttributes,
                                                    lpThreadAttributes,
                                                    NULL);

    /* Create the Kernel Thread Object */
    Status = NtCreateThread(&hThread,
                            THREAD_ALL_ACCESS,
                            ObjectAttributes,
                            hProcess,
                            &ClientId,
                            &Context,
                            &InitialTeb,
                            TRUE);
    if(!NT_SUCCESS(Status))
    {
        BasepFreeStack(hProcess, &InitialTeb);
        SetLastErrorByStatus(Status);
        return NULL;
    }

    /* Are we in the same process? */
    if (hProcess == NtCurrentProcess())
    {
        PTEB Teb;
        PVOID ActivationContextStack;
        THREAD_BASIC_INFORMATION ThreadBasicInfo;
#ifndef SXS_SUPPORT_FIXME
        ACTIVATION_CONTEXT_BASIC_INFORMATION ActivationCtxInfo;
        ULONG_PTR Cookie;
#endif
        ULONG retLen;

        /* Get the TEB */
        Status = NtQueryInformationThread(hThread,
                                          ThreadBasicInformation,
                                          &ThreadBasicInfo,
                                          sizeof(ThreadBasicInfo),
                                          &retLen);
        if (NT_SUCCESS(Status))
        {
            /* Allocate the Activation Context Stack */
            Status = RtlAllocateActivationContextStack(&ActivationContextStack);
        }

        if (NT_SUCCESS(Status))
        {
            Teb = ThreadBasicInfo.TebBaseAddress;

            /* Save it */
            Teb->ActivationContextStackPointer = ActivationContextStack;
#ifndef SXS_SUPPORT_FIXME
            /* Query the Context */
            Status = RtlQueryInformationActivationContext(1,
                                                          0,
                                                          NULL,
                                                          ActivationContextBasicInformation,
                                                          &ActivationCtxInfo,
                                                          sizeof(ActivationCtxInfo),
                                                          &retLen);
            if (NT_SUCCESS(Status))
            {
                /* Does it need to be activated? */
                if (!ActivationCtxInfo.hActCtx)
                {
                    /* Activate it */
                    Status = RtlActivateActivationContext(1,
                                                          ActivationCtxInfo.hActCtx,
                                                          &Cookie);
                    if (!NT_SUCCESS(Status))
                        DPRINT1("RtlActivateActivationContext failed %x\n", Status);
                }
            }
            else
                DPRINT1("RtlQueryInformationActivationContext failed %x\n", Status);
#endif
        }
        else
            DPRINT1("RtlAllocateActivationContextStack failed %x\n", Status);
    }

    /* Notify CSR */
    Status = BasepNotifyCsrOfThread(hThread, &ClientId);
    if (!NT_SUCCESS(Status))
    {
        ASSERT(FALSE);
    }
    
    /* Success */
    if(lpThreadId) *lpThreadId = HandleToUlong(ClientId.UniqueThread);

    /* Resume it if asked */
    if (!(dwCreationFlags & CREATE_SUSPENDED))
    {
        NtResumeThread(hThread, &Dummy);
    }

    /* Return handle to thread */
    return hThread;
}

/*
 * @implemented
 */
VOID
WINAPI
ExitThread(DWORD uExitCode)
{
    NTSTATUS Status;
    ULONG LastThread;

    /*
     * Terminate process if this is the last thread
     * of the current process
     */
    Status = NtQueryInformationThread(NtCurrentThread(),
                                      ThreadAmILastThread,
                                      &LastThread,
                                      sizeof(LastThread),
                                      NULL);
    if (NT_SUCCESS(Status) && LastThread)
    {
        /* Exit the Process */
        ExitProcess(uExitCode);
    }

    /* Notify DLLs and TLS Callbacks of termination */
    LdrShutdownThread();

    /* Tell the Kernel to free the Stack */
    NtCurrentTeb()->FreeStackOnTermination = TRUE;
    NtTerminateThread(NULL, uExitCode);

    /* We should never reach this place */
    DPRINT1("It should not happen\n");
    while (TRUE) ;
}

/*
 * @implemented
 */
HANDLE
WINAPI
OpenThread(DWORD dwDesiredAccess,
           BOOL bInheritHandle,
           DWORD dwThreadId)
{
    NTSTATUS Status;
    HANDLE ThreadHandle;
    OBJECT_ATTRIBUTES ObjectAttributes;
    CLIENT_ID ClientId ;

    ClientId.UniqueProcess = 0;
    ClientId.UniqueThread = ULongToHandle(dwThreadId);

    InitializeObjectAttributes(&ObjectAttributes,
                               NULL,
                               (bInheritHandle ? OBJ_INHERIT : 0),
                               NULL,
                               NULL);

    Status = NtOpenThread(&ThreadHandle,
                          dwDesiredAccess,
                          &ObjectAttributes,
                          &ClientId);
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return NULL;
    }

    return ThreadHandle;
}

/*
 * @implemented
 */
PTEB
GetTeb(VOID)
{
    return NtCurrentTeb();
}

/*
 * @implemented
 */
BOOL
WINAPI
SwitchToThread(VOID)
{
    return NtYieldExecution() != STATUS_NO_YIELD_PERFORMED;
}


/*
 * @implemented
 */
DWORD
WINAPI
GetCurrentThreadId(VOID)
{
    return HandleToUlong(NtCurrentTeb()->ClientId.UniqueThread);
}

/*
 * @implemented
 */
BOOL
NTAPI
GetThreadTimes(HANDLE hThread,
               LPFILETIME lpCreationTime,
               LPFILETIME lpExitTime,
               LPFILETIME lpKernelTime,
               LPFILETIME lpUserTime)
{
    KERNEL_USER_TIMES KernelUserTimes;
    NTSTATUS Status;

    Status = NtQueryInformationThread(hThread,
                                      ThreadTimes,
                                      &KernelUserTimes,
                                      sizeof(KERNEL_USER_TIMES),
                                      NULL);
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return(FALSE);
    }

    *lpCreationTime = *(LPFILETIME)&KernelUserTimes.CreateTime;
    *lpExitTime = *(LPFILETIME)&KernelUserTimes.ExitTime;
    *lpKernelTime = *(LPFILETIME)&KernelUserTimes.KernelTime;
    *lpUserTime = *(LPFILETIME)&KernelUserTimes.UserTime;
    return TRUE;
}

/*
 * @implemented
 */
BOOL
WINAPI
GetThreadContext(HANDLE hThread,
                 LPCONTEXT lpContext)
{
    NTSTATUS Status;

    Status = NtGetContextThread(hThread, lpContext);
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return FALSE;
    }

    return TRUE;
}

/*
 * @implemented
 */
BOOL
WINAPI
SetThreadContext(HANDLE hThread,
                 CONST CONTEXT *lpContext)
{
    NTSTATUS Status;

    Status = NtSetContextThread(hThread, (PCONTEXT)lpContext);
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return FALSE;
    }

    return TRUE;
}

/*
 * @implemented
 */
BOOL
WINAPI
GetExitCodeThread(HANDLE hThread,
                  LPDWORD lpExitCode)
{
    THREAD_BASIC_INFORMATION ThreadBasic;
    NTSTATUS Status;

    Status = NtQueryInformationThread(hThread,
                                      ThreadBasicInformation,
                                      &ThreadBasic,
                                      sizeof(THREAD_BASIC_INFORMATION),
                                      NULL);
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return(FALSE);
    }

    *lpExitCode = ThreadBasic.ExitStatus;
    return TRUE;
}

/*
 * @implemented
 */
DWORD
WINAPI
ResumeThread(HANDLE hThread)
{
    ULONG PreviousResumeCount;
    NTSTATUS Status;

    Status = NtResumeThread(hThread, &PreviousResumeCount);
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return -1;
    }

    return PreviousResumeCount;
}

/*
 * @implemented
 */
BOOL
WINAPI
TerminateThread(HANDLE hThread,
                DWORD dwExitCode)
{
    NTSTATUS Status;

    if (!hThread)
    {
        SetLastError(ERROR_INVALID_HANDLE);
        return FALSE;
    }

    Status = NtTerminateThread(hThread, dwExitCode);
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return FALSE;
    }

    return TRUE;
}

/*
 * @implemented
 */
DWORD
WINAPI
SuspendThread(HANDLE hThread)
{
    ULONG PreviousSuspendCount;
    NTSTATUS Status;

    Status = NtSuspendThread(hThread, &PreviousSuspendCount);
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return -1;
    }

    return PreviousSuspendCount;
}

/*
 * @implemented
 */
DWORD_PTR
WINAPI
SetThreadAffinityMask(HANDLE hThread,
                      DWORD_PTR dwThreadAffinityMask)
{
    THREAD_BASIC_INFORMATION ThreadBasic;
    KAFFINITY AffinityMask;
    NTSTATUS Status;

    AffinityMask = (KAFFINITY)dwThreadAffinityMask;

    Status = NtQueryInformationThread(hThread,
                                      ThreadBasicInformation,
                                      &ThreadBasic,
                                      sizeof(THREAD_BASIC_INFORMATION),
                                      NULL);
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return 0;
    }

    Status = NtSetInformationThread(hThread,
                                    ThreadAffinityMask,
                                    &AffinityMask,
                                    sizeof(KAFFINITY));
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        ThreadBasic.AffinityMask = 0;
    }

    return ThreadBasic.AffinityMask;
}

/*
 * @implemented
 */
BOOL
WINAPI
SetThreadPriority(HANDLE hThread,
                  int nPriority)
{
    LONG Prio = nPriority;
    NTSTATUS Status;

    /* Check if values forcing saturation should be used */
    if (Prio == THREAD_PRIORITY_TIME_CRITICAL)
    {
        Prio = (HIGH_PRIORITY + 1) / 2;
    }
    else if (Prio == THREAD_PRIORITY_IDLE)
    {
        Prio = -((HIGH_PRIORITY + 1) / 2);
    }

    /* Set the Base Priority */
    Status = NtSetInformationThread(hThread,
                                    ThreadBasePriority,
                                    &Prio,
                                    sizeof(LONG));
    if (!NT_SUCCESS(Status))
    {
        /* Failure */
        SetLastErrorByStatus(Status);
        return FALSE;
    }

    /* Return */
    return TRUE;
}

/*
 * @implemented
 */
int
WINAPI
GetThreadPriority(HANDLE hThread)
{
    THREAD_BASIC_INFORMATION ThreadBasic;
    NTSTATUS Status;

    /* Query the Base Priority Increment */
    Status = NtQueryInformationThread(hThread,
                                      ThreadBasicInformation,
                                      &ThreadBasic,
                                      sizeof(THREAD_BASIC_INFORMATION),
                                      NULL);
    if (!NT_SUCCESS(Status))
    {
        /* Failure */
        SetLastErrorByStatus(Status);
        return THREAD_PRIORITY_ERROR_RETURN;
    }

    /* Do some conversions for out of boundary values */
    if (ThreadBasic.BasePriority > THREAD_BASE_PRIORITY_MAX)
    {
        ThreadBasic.BasePriority = THREAD_PRIORITY_TIME_CRITICAL;
    }
    else if (ThreadBasic.BasePriority < THREAD_BASE_PRIORITY_MIN)
    {
        ThreadBasic.BasePriority = THREAD_PRIORITY_IDLE;
    }

    /* Return the final result */
    return ThreadBasic.BasePriority;
}

/*
 * @implemented
 */
BOOL
WINAPI
GetThreadPriorityBoost(IN HANDLE hThread,
                       OUT PBOOL pDisablePriorityBoost)
{
    ULONG PriorityBoost;
    NTSTATUS Status;

    Status = NtQueryInformationThread(hThread,
                                      ThreadPriorityBoost,
                                      &PriorityBoost,
                                      sizeof(ULONG),
                                      NULL);
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return FALSE;
    }

    *pDisablePriorityBoost = PriorityBoost;
    return TRUE;
}

/*
 * @implemented
 */
BOOL
NTAPI
SetThreadPriorityBoost(IN HANDLE hThread,
                       IN BOOL bDisablePriorityBoost)
{
    ULONG PriorityBoost;
    NTSTATUS Status;

    PriorityBoost = (ULONG)bDisablePriorityBoost;

    Status = NtSetInformationThread(hThread,
                                    ThreadPriorityBoost,
                                    &PriorityBoost,
                                    sizeof(ULONG));
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return FALSE;
    }

    return TRUE;
}

/*
 * @implemented
 */
BOOL
WINAPI
GetThreadSelectorEntry(IN HANDLE hThread,
                       IN DWORD dwSelector,
                       OUT LPLDT_ENTRY lpSelectorEntry)
{
#ifdef _M_IX86
    DESCRIPTOR_TABLE_ENTRY DescriptionTableEntry;
    NTSTATUS Status;

    /* Set the selector and do the query */
    DescriptionTableEntry.Selector = dwSelector;
    Status = NtQueryInformationThread(hThread,
                                      ThreadDescriptorTableEntry,
                                      &DescriptionTableEntry,
                                      sizeof(DESCRIPTOR_TABLE_ENTRY),
                                      NULL);
    if (!NT_SUCCESS(Status))
    {
        /* Fail */
        SetLastErrorByStatus(Status);
        return FALSE;
    }

    /* Success, return the selector */
    *lpSelectorEntry = DescriptionTableEntry.Descriptor;
    return TRUE;
#else
    DPRINT1("Calling GetThreadSelectorEntry!\n");
    return FALSE;
#endif
}

/*
 * @implemented
 */
DWORD
WINAPI
SetThreadIdealProcessor(HANDLE hThread,
                        DWORD dwIdealProcessor)
{
    NTSTATUS Status;

    Status = NtSetInformationThread(hThread,
                                    ThreadIdealProcessor,
                                    &dwIdealProcessor,
                                    sizeof(ULONG));
    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return -1;
    }

    return (DWORD)Status;
}

/*
 * @implemented
 */
DWORD WINAPI
GetProcessIdOfThread(HANDLE Thread)
{
  THREAD_BASIC_INFORMATION ThreadBasic;
  NTSTATUS Status;

  Status = NtQueryInformationThread(Thread,
                                    ThreadBasicInformation,
                                    &ThreadBasic,
                                    sizeof(THREAD_BASIC_INFORMATION),
                                    NULL);
  if(!NT_SUCCESS(Status))
  {
    SetLastErrorByStatus(Status);
    return 0;
  }

  return HandleToUlong(ThreadBasic.ClientId.UniqueProcess);
}

/*
 * @implemented
 */
DWORD WINAPI
GetThreadId(HANDLE Thread)
{
  THREAD_BASIC_INFORMATION ThreadBasic;
  NTSTATUS Status;

  Status = NtQueryInformationThread(Thread,
                                    ThreadBasicInformation,
                                    &ThreadBasic,
                                    sizeof(THREAD_BASIC_INFORMATION),
                                    NULL);
  if(!NT_SUCCESS(Status))
  {
    SetLastErrorByStatus(Status);
    return 0;
  }

  return HandleToUlong(ThreadBasic.ClientId.UniqueThread);
}

/*
 * @unimplemented
 */
LANGID WINAPI
SetThreadUILanguage(LANGID LangId)
{
  DPRINT1("SetThreadUILanguage(0x%4x) unimplemented!\n", LangId);
  return LangId;
}

static void CALLBACK
IntCallUserApc(PVOID Function, PVOID dwData, PVOID Argument3)
{
   PAPCFUNC pfnAPC = (PAPCFUNC)Function;
   pfnAPC((ULONG_PTR)dwData);
}

/*
 * @implemented
 */
DWORD WINAPI
QueueUserAPC(PAPCFUNC pfnAPC, HANDLE hThread, ULONG_PTR dwData)
{
  NTSTATUS Status;

  Status = NtQueueApcThread(hThread, IntCallUserApc, pfnAPC,
                            (PVOID)dwData, NULL);
  if (!NT_SUCCESS(Status))
  {
    SetLastErrorByStatus(Status);
    return 0;
  }

  return 1;
}

/*
 * @implemented
 */
BOOL WINAPI
GetThreadIOPendingFlag(HANDLE hThread,
                       PBOOL lpIOIsPending)
{
  ULONG IoPending;
  NTSTATUS Status;

  if(lpIOIsPending == NULL)
  {
    SetLastError(ERROR_INVALID_PARAMETER);
    return FALSE;
  }

  Status = NtQueryInformationThread(hThread,
                                    ThreadIsIoPending,
                                    (PVOID)&IoPending,
                                    sizeof(IoPending),
                                    NULL);
  if(NT_SUCCESS(Status))
  {
    *lpIOIsPending = ((IoPending != 0) ? TRUE : FALSE);
    return TRUE;
  }

  SetLastErrorByStatus(Status);
  return FALSE;
}


/*
 * @implemented
 */
VOID WINAPI
Sleep(DWORD dwMilliseconds)
{
  SleepEx(dwMilliseconds, FALSE);
  return;
}


/*
 * @implemented
 */
DWORD WINAPI
SleepEx(DWORD dwMilliseconds,
	BOOL bAlertable)
{
  LARGE_INTEGER Interval;
  NTSTATUS errCode;

  if (dwMilliseconds != INFINITE)
    {
      /*
       * System time units are 100 nanoseconds (a nanosecond is a billionth of
       * a second).
       */
      Interval.QuadPart = -((LONGLONG)dwMilliseconds * 10000);
    }
  else
    {
      /* Approximately 292000 years hence */
      Interval.QuadPart = -0x7FFFFFFFFFFFFFFFLL;
    }

dowait:
  errCode = NtDelayExecution ((BOOLEAN)bAlertable, &Interval);
  if ((bAlertable) && (errCode == STATUS_ALERTED)) goto dowait;
  return (errCode == STATUS_USER_APC) ? WAIT_IO_COMPLETION : 0;
}


typedef struct _QUEUE_USER_WORKITEM_CONTEXT
{
    LPTHREAD_START_ROUTINE Function;
    PVOID Context;
} QUEUE_USER_WORKITEM_CONTEXT, *PQUEUE_USER_WORKITEM_CONTEXT;

static VOID
NTAPI
InternalWorkItemTrampoline(PVOID Context)
{
    QUEUE_USER_WORKITEM_CONTEXT Info;

    ASSERT(Context);

    /* Save the context to the stack */
    Info = *(volatile QUEUE_USER_WORKITEM_CONTEXT *)Context;

    /* Free the context before calling the callback. This avoids
       a memory leak in case the thread dies... */
    RtlFreeHeap(RtlGetProcessHeap(),
                0,
                Context);

    /* Call the real callback */
    Info.Function(Info.Context);
}


/*
 * @implemented
 */
BOOL
WINAPI
QueueUserWorkItem(
    LPTHREAD_START_ROUTINE Function,
    PVOID Context,
    ULONG Flags
    )
{
    PQUEUE_USER_WORKITEM_CONTEXT WorkItemContext;
    NTSTATUS Status;

    /* Save the context for the trampoline function */
    WorkItemContext = RtlAllocateHeap(RtlGetProcessHeap(),
                                      0,
                                      sizeof(*WorkItemContext));
    if (WorkItemContext == NULL)
    {
        SetLastError(ERROR_NOT_ENOUGH_MEMORY);
        return FALSE;
    }

    WorkItemContext->Function = Function;
    WorkItemContext->Context = Context;

    /* NOTE: Don't use Function directly since the callback signature
             differs. This might cause problems on certain platforms... */
    Status = RtlQueueWorkItem(InternalWorkItemTrampoline,
                              WorkItemContext,
                              Flags);
    if (!NT_SUCCESS(Status))
    {
        /* Free the allocated context in case of failure */
        RtlFreeHeap(RtlGetProcessHeap(),
                    0,
                    WorkItemContext);

        SetLastErrorByStatus(Status);
        return FALSE;
    }

    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
RegisterWaitForSingleObject(
    PHANDLE phNewWaitObject,
    HANDLE hObject,
    WAITORTIMERCALLBACK Callback,
    PVOID Context,
    ULONG dwMilliseconds,
    ULONG dwFlags
    )
{
    NTSTATUS Status = RtlRegisterWait(phNewWaitObject,
                                      hObject,
                                      Callback,
                                      Context,
                                      dwMilliseconds,
                                      dwFlags);

    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return FALSE;
    }
    return TRUE;
}


/*
 * @implemented
 */
HANDLE
WINAPI
RegisterWaitForSingleObjectEx(
    HANDLE hObject,
    WAITORTIMERCALLBACK Callback,
    PVOID Context,
    ULONG dwMilliseconds,
    ULONG dwFlags
    )
{
    NTSTATUS Status;
    HANDLE hNewWaitObject;

    Status = RtlRegisterWait(&hNewWaitObject,
                             hObject,
                             Callback,
                             Context,
                             dwMilliseconds,
                             dwFlags);

    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return NULL;
    }

    return hNewWaitObject;
}


/*
 * @implemented
 */
BOOL
WINAPI
UnregisterWait(
    HANDLE WaitHandle
    )
{
    NTSTATUS Status = RtlDeregisterWaitEx(WaitHandle, NULL);

    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return FALSE;
    }

    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
UnregisterWaitEx(
    HANDLE WaitHandle,
    HANDLE CompletionEvent
    )
{
    NTSTATUS Status = RtlDeregisterWaitEx(WaitHandle, CompletionEvent);

    if (!NT_SUCCESS(Status))
    {
        SetLastErrorByStatus(Status);
        return FALSE;
    }

    return TRUE;
}

/* EOF */