reactos/lib/rtl/vectoreh.c

   1 /*
   2  * COPYRIGHT:         See COPYING in the top level directory
   3  * PROJECT:           ReactOS sysem libraries
   4  * PURPOSE:           Vectored Exception Handling
   5  * FILE:              lib/rtl/vectoreh.c
   6  * PROGRAMERS:        Thomas Weidenmueller
   7  */
   8
   9 /* INCLUDES *****************************************************************/
  10
  11 #include <rtl.h>
  12
  13 #define NDEBUG
  14 #include <debug.h>
  15
  16 static RTL_CRITICAL_SECTION RtlpVectoredExceptionLock;
  17 static LIST_ENTRY RtlpVectoredExceptionHead;
  18
  19 typedef struct _RTL_VECTORED_EXCEPTION_HANDLER
  20 {
  21   LIST_ENTRY ListEntry;
  22   PVECTORED_EXCEPTION_HANDLER VectoredHandler;
  23 } RTL_VECTORED_EXCEPTION_HANDLER, *PRTL_VECTORED_EXCEPTION_HANDLER;
  24
  25 /* FIXME - stupid ld won't resolve RtlDecodePointer! Since their implementation
  26            is the same just use RtlEncodePointer for now! */
  27 #define RtlDecodePointer RtlEncodePointer
  28
  29 /* FUNCTIONS ***************************************************************/
  30
  31 EXCEPTION_DISPOSITION NTAPI
  32 RtlpExecuteVectoredExceptionHandlers(IN PEXCEPTION_RECORD  ExceptionRecord,
  33                                      IN PCONTEXT  Context)
  34 {
  35   PLIST_ENTRY CurrentEntry;
  36   PRTL_VECTORED_EXCEPTION_HANDLER veh;
  37   PVECTORED_EXCEPTION_HANDLER VectoredHandler;
  38   EXCEPTION_POINTERS ExceptionInfo;
  39
  40   ExceptionInfo.ExceptionRecord = ExceptionRecord;
  41   ExceptionInfo.ContextRecord = Context;
  42
  43   if(RtlpVectoredExceptionHead.Flink != &RtlpVectoredExceptionHead)
  44   {
  45     RtlEnterCriticalSection(&RtlpVectoredExceptionLock);
  46     for(CurrentEntry = RtlpVectoredExceptionHead.Flink;
  47         CurrentEntry != &RtlpVectoredExceptionHead;
  48         CurrentEntry = CurrentEntry->Flink)
  49     {
  50       veh = CONTAINING_RECORD(CurrentEntry,
  51                               RTL_VECTORED_EXCEPTION_HANDLER,
  52                               ListEntry);
  53       VectoredHandler = RtlDecodePointer(veh->VectoredHandler);
  54       RtlLeaveCriticalSection(&RtlpVectoredExceptionLock);
  55
  56       if(VectoredHandler(&ExceptionInfo) == EXCEPTION_CONTINUE_EXECUTION)
  57       {
  58         return ExceptionContinueSearch;
  59       }
  60
  61       RtlEnterCriticalSection(&RtlpVectoredExceptionLock);
  62     }
  63     RtlLeaveCriticalSection(&RtlpVectoredExceptionLock);
  64   }
  65
  66   return ExceptionContinueExecution;
  67 }
  68
  69 VOID
  70 RtlpInitializeVectoredExceptionHandling(VOID)
  71 {
  72   InitializeListHead(&RtlpVectoredExceptionHead);
  73   RtlInitializeCriticalSection(&RtlpVectoredExceptionLock);
  74 }
  75
  76
  77 /*
  78  * @implemented
  79  */
  80 PVOID NTAPI
  81 RtlAddVectoredExceptionHandler(IN ULONG FirstHandler,
  82                                IN PVECTORED_EXCEPTION_HANDLER VectoredHandler)
  83 {
  84   PRTL_VECTORED_EXCEPTION_HANDLER veh;
  85
  86   veh = RtlAllocateHeap(RtlGetProcessHeap(),
  87                         0,
  88                         sizeof(RTL_VECTORED_EXCEPTION_HANDLER));
  89   if(veh != NULL)
  90   {
  91     veh->VectoredHandler = RtlEncodePointer(VectoredHandler);
  92     RtlEnterCriticalSection(&RtlpVectoredExceptionLock);
  93     if(FirstHandler != 0)
  94     {
  95       InsertHeadList(&RtlpVectoredExceptionHead,
  96                      &veh->ListEntry);
  97     }
  98     else
  99     {
 100       InsertTailList(&RtlpVectoredExceptionHead,
 101                      &veh->ListEntry);
 102     }
 103     RtlLeaveCriticalSection(&RtlpVectoredExceptionLock);
 104   }
 105
 106   return veh;
 107 }
 108
 109
 110 /*
 111  * @implemented
 112  */
 113 ULONG NTAPI
 114 RtlRemoveVectoredExceptionHandler(IN PVOID VectoredHandlerHandle)
 115 {
 116   PLIST_ENTRY CurrentEntry;
 117   PRTL_VECTORED_EXCEPTION_HANDLER veh = NULL;
 118   ULONG Removed = FALSE;
 119
 120   RtlEnterCriticalSection(&RtlpVectoredExceptionLock);
 121   for(CurrentEntry = RtlpVectoredExceptionHead.Flink;
 122       CurrentEntry != &RtlpVectoredExceptionHead;
 123       CurrentEntry = CurrentEntry->Flink)
 124   {
 125     veh = CONTAINING_RECORD(CurrentEntry,
 126                             RTL_VECTORED_EXCEPTION_HANDLER,
 127                             ListEntry);
 128     if(veh == VectoredHandlerHandle)
 129     {
 130       RemoveEntryList(&veh->ListEntry);
 131       Removed = TRUE;
 132       break;
 133     }
 134   }
 135   RtlLeaveCriticalSection(&RtlpVectoredExceptionLock);
 136
 137   if(Removed)
 138   {
 139     RtlFreeHeap(RtlGetProcessHeap(),
 140                 0,
 141                 veh);
 142   }
 143
 144   return Removed;
 145 }
 146
 147 /* EOF */