From 83991b37500a18b072dc12a29e8d208265bf69e2 Mon Sep 17 00:00:00 2001
From: Timo Kreuzer <timo.kreuzer@reactos.org>
Date: Mon, 17 Nov 2008 23:24:59 +0000
Subject: [PATCH] Implement RtlGetCallersAddress

svn path=/branches/ros-amd64-bringup/; revision=37425
---
 reactos/lib/rtl/amd64/unwind.c | 30 ++++++++++++++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/reactos/lib/rtl/amd64/unwind.c b/reactos/lib/rtl/amd64/unwind.c
index 20ed21fd976..8374b2bfa9f 100644
--- a/reactos/lib/rtl/amd64/unwind.c
+++ b/reactos/lib/rtl/amd64/unwind.c
@@ -332,7 +332,7 @@ RtlWalkFrameChain(OUT PVOID *Callers,
 {
     CONTEXT Context;
     ULONG64 ControlPc, ImageBase, EstablisherFrame;
-    ULONG64 StackBegin, StackEnd;
+    ULONG64 StackLow, StackHigh;
     PVOID HandlerData;
     INT i;
     PRUNTIME_FUNCTION FunctionEntry;
@@ -341,7 +341,7 @@ DPRINT1("RtlWalkFrameChain called\n");
 
     ControlPc = Context.Rip;
 
-    RtlpGetStackLimits(&StackBegin, &StackEnd);
+    RtlpGetStackLimits(&StackLow, &StackHigh);
 
     /* Check if we want the user-mode stack frame */
     if (Flags == 1)
@@ -384,3 +384,29 @@ DPRINT1("RtlWalkFrameChain called\n");
     return i;
 }
 
+// CHEKCME: return PVOID?
+// http://undocumented.ntinternals.net/UserMode/Undocumented%20Functions/Debug/RtlGetCallersAddress.html
+VOID
+NTAPI
+RtlGetCallersAddress(
+    OUT PVOID *CallersAddress,
+    OUT PVOID *CallersCaller )
+{
+    PVOID Callers[4];
+    ULONG Number;
+
+    /* Get callers:
+     * RtlWalkFrameChain -> RtlGetCallersAddress -> x -> y */
+    Number = RtlWalkFrameChain(Callers, 4, 0);
+
+    if (CallersAddress)
+    {
+        *CallersAddress = (Number >= 3) ? Callers[2] : NULL;
+    }
+    if (CallersCaller)
+    {
+        *CallersCaller = (Number == 4) ? Callers[3] : NULL;
+    }
+
+    return;
+}