Fixed some slightl logical flaws in PSEH
Experimental changes to _SEHUnwind: make less assumptions about the correctness of RtlUnwind

reactos/lib/pseh

diff -u -r1.4 -r1.4.2.1
--- framebased.c	21 Jun 2004 20:55:16 -0000	1.4
+++ framebased.c	26 Jun 2004 16:36:36 -0000	1.4.2.1
@@ -38,10 +38,14 @@

 extern void __stdcall RtlUnwind(void *, void *, void *, void *);
 void const * _SEHRtlUnwind = RtlUnwind;
 

+extern void __cdecl DbgPrint(const char *, ...);
+

 __declspec(noreturn) void __cdecl _SEHCallHandler(_SEHPortableFrame_t * frame)
 {
  frame->SPF_Handling = 1;

+ DbgPrint("Before _SEHUnwind\n");

  _SEHUnwind(frame);

+ DbgPrint("After _SEHUnwind\n");

  frame->SPF_Handlers->SH_Handler(frame);
 }
 

@@ -62,52 +66,68 @@

  /* Unwinding */
  if(ExceptionRecord->ExceptionFlags & (4 | 2))
  {

+  DbgPrint("_SEHFrameHandler unwinding\n");
+

   if(frame->SPF_Handlers->SH_Finally && !frame->SPF_Handling)
    frame->SPF_Handlers->SH_Finally(frame);
  }
  /* Handling */
  else
  {

+  int ret;
+
+  DbgPrint("_SEHFrameHandler handling\n");
+

   if(ExceptionRecord->ExceptionCode)
    frame->SPF_Code = ExceptionRecord->ExceptionCode;
   else
    frame->SPF_Code = 0xC0000001; 
 

-  if(frame->SPF_Handlers->SH_Filter)

+  switch((UINT_PTR)frame->SPF_Handlers->SH_Filter)

   {

-   int ret;
-
-   switch((UINT_PTR)frame->SPF_Handlers->SH_Filter)

+   case _SEH_EXECUTE_HANDLER + 1:
+   case _SEH_CONTINUE_SEARCH + 1:
+   case _SEH_CONTINUE_EXECUTION + 1:

    {

-    case _SEH_EXECUTE_HANDLER + 1:
-    case _SEH_CONTINUE_SEARCH + 1:
-    case _SEH_CONTINUE_EXECUTION + 1:
-    {
-     ret = (int)((UINT_PTR)frame->SPF_Handlers->SH_Filter) - 1;
-     break;
-    }

+    ret = (int)((UINT_PTR)frame->SPF_Handlers->SH_Filter) - 1;
+    break;
+   }

-    default:

+   default:
+   {
+    if(frame->SPF_Handlers->SH_Filter)

     {
      EXCEPTION_POINTERS ep;

-

+ 

      ep.ExceptionRecord = ExceptionRecord;
      ep.ContextRecord = ContextRecord;

-

+ 

      ret = frame->SPF_Handlers->SH_Filter(&ep, frame);

-     break;

     }

+    else
+     ret = _SEH_CONTINUE_SEARCH;
+
+    break;

    }

+  }

-   /* _SEH_CONTINUE_EXECUTION */
-   if(ret < 0)
-    return ExceptionContinueExecution;
-   /* _SEH_EXECUTE_HANDLER */
-   else if(ret > 0)
-    _SEHCallHandler(frame);
-   /* _SEH_CONTINUE_SEARCH */
-   else
-    /* fall through */;

+  /* _SEH_CONTINUE_EXECUTION */
+  if(ret < 0)
+  {
+   DbgPrint("_SEHFrameHandler: ExceptionContinueExecution\n");
+   return ExceptionContinueExecution;
+  }
+  /* _SEH_EXECUTE_HANDLER */
+  else if(ret > 0)
+  {
+   DbgPrint("_SEHFrameHandler: call handler\n");
+   _SEHCallHandler(frame);
+  }
+  /* _SEH_CONTINUE_SEARCH */
+  else
+  {
+   DbgPrint("_SEHFrameHandler: ExceptionContinueSearch\n");
+   /* fall through */;

   }
  }
 

reactos/lib/pseh/i386

diff -u -r1.4 -r1.4.6.1
--- framebased.asm	3 Jun 2004 22:19:10 -0000	1.4
+++ framebased.asm	26 Jun 2004 16:36:36 -0000	1.4.6.1
@@ -54,12 +54,15 @@

  push ebx
 
  xor eax, eax

- push eax
- push eax
- push eax
- push ecx

+ push esp    ; ReturnValue
+ push eax    ; ExceptionRecord
+ push .leave ; TargetIp
+ push ecx    ; TargetFrame

  call [__SEHRtlUnwind]
 

+.leave
+ mov esp, eax
+

  pop ebx
  pop edi
  pop esi