reactos/ntoskrnl/ke/event.c

   1 /*
   2  * COPYRIGHT:       See COPYING in the top level directory
   3  * PROJECT:         ReactOS kernel
   4  * FILE:            ntoskrnl/ke/event.c
   5  * PURPOSE:         Implements event
   6  * PROGRAMMER:      David Welch (welch@mcmail.com)
   7  * UPDATE HISTORY:
   8  *                  Created 22/05/98
   9  */
  10
  11 /* INCLUDES *****************************************************************/
  12
  13 #include <internal/kernel.h>
  14 #include <internal/wait.h>
  15
  16 #include <ddk/ntddk.h>
  17
  18 #include <internal/debug.h>
  19
  20 /* FUNCTIONS ****************************************************************/
  21
  22 VOID KeClearEvent(PKEVENT Event)
  23 {
  24    Event->Header.SignalState=FALSE;   // (??) Is this atomic
  25 }
  26
  27 VOID KeInitializeEvent(PKEVENT Event, EVENT_TYPE Type, BOOLEAN State)
  28 {
  29    Event->Header.Type = Type;
  30    Event->Header.Absolute = 0;
  31    Event->Header.Inserted = 0;
  32    Event->Header.Size = sizeof(KEVENT) / sizeof(ULONG);
  33    Event->Header.SignalState = State;
  34    InitializeListHead(&(Event->Header.WaitListHead));
  35 }
  36
  37 LONG KeReadStateEvent(PKEVENT Event)
  38 {
  39    return(Event->Header.SignalState);
  40 }
  41
  42 LONG KeResetEvent(PKEVENT Event)
  43 {
  44    return(InterlockedExchange(&(Event->Header.SignalState),0));
  45 }
  46
  47 LONG KeSetEvent(PKEVENT Event, KPRIORITY Increment, BOOLEAN Wait)
  48 {
  49    int ret;
  50    KIRQL oldlvl;
  51
  52    KeAcquireSpinLock(&DispatcherDatabaseLock,&oldlvl);
  53    ret = InterlockedExchange(&(Event->Header.SignalState),1);
  54    KeDispatcherObjectWake((DISPATCHER_HEADER *)Event);
  55    KeReleaseSpinLock(&DispatcherDatabaseLock,oldlvl);
  56 }