Make sure changes to the debug registers while inside a SIGTRAP
exception are taken into account (based on a patch by Alex Pasadyn).
diff --git a/dlls/ntdll/signal_i386.c b/dlls/ntdll/signal_i386.c
index 5ad70a6..cc08a36 100644
--- a/dlls/ntdll/signal_i386.c
+++ b/dlls/ntdll/signal_i386.c
@@ -836,6 +836,7 @@
static void do_trap( CONTEXT *context, int trap_code )
{
EXCEPTION_RECORD rec;
+ DWORD dr0, dr1, dr2, dr3, dr6, dr7;
rec.ExceptionFlags = EXCEPTION_CONTINUABLE;
rec.ExceptionRecord = NULL;
@@ -845,18 +846,15 @@
switch(trap_code)
{
case T_TRCTRAP: /* Single-step exception */
+ rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
if (context->EFlags & 0x100)
{
- rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
context->EFlags &= ~0x100; /* clear single-step flag */
}
- else
+ else /* hardware breakpoint, fetch the debug registers */
{
- /* likely we get this because of a kill(SIGTRAP) on ourself,
- * so send a bp exception instead of a single step exception
- */
- TRACE("Spurious single step trap => breakpoint simulation\n");
- rec.ExceptionCode = EXCEPTION_BREAKPOINT;
+ context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
+ GetThreadContext(GetCurrentThread(), context);
}
break;
case T_BPTFLT: /* Breakpoint exception */
@@ -866,7 +864,22 @@
rec.ExceptionCode = EXCEPTION_BREAKPOINT;
break;
}
+ dr0 = context->Dr0;
+ dr1 = context->Dr1;
+ dr2 = context->Dr2;
+ dr3 = context->Dr3;
+ dr6 = context->Dr6;
+ dr7 = context->Dr7;
+
EXC_RtlRaiseException( &rec, context );
+
+ if (dr0 != context->Dr0 || dr1 != context->Dr1 || dr2 != context->Dr2 ||
+ dr3 != context->Dr3 || dr6 != context->Dr6 || dr7 != context->Dr7)
+ {
+ /* the debug registers have changed, set the new values */
+ context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
+ SetThreadContext(GetCurrentThread(), context);
+ }
}