From 6ff349c2f6d7d21f2bbe8d14e096e507429a08c6 Mon Sep 17 00:00:00 2001
From: Andy McFadden <fadden@fadden.com>
Date: Fri, 24 Jan 2020 15:25:01 -0800
Subject: [PATCH] Fix crashing bug in Goto

The application would crash if an invalid file offset was entered
(with "+xxxx").  This bug has been present since v1.0.
---
 SourceGen/WpfGui/GotoBox.xaml.cs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/SourceGen/WpfGui/GotoBox.xaml.cs b/SourceGen/WpfGui/GotoBox.xaml.cs
index 3e95c53..5144c99 100644
--- a/SourceGen/WpfGui/GotoBox.xaml.cs
+++ b/SourceGen/WpfGui/GotoBox.xaml.cs
@@ -136,7 +136,10 @@ namespace SourceGen.WpfGui {
             if (input[0] == '+') {
                 // this can only be an offset; convert as hexadecimal number
                 try {
-                    TargetOffset = Convert.ToInt32(input.Substring(1), 16);
+                    int offset = Convert.ToInt32(input.Substring(1), 16);
+                    if (offset >= 0 && offset < mProject.FileDataLength) {
+                        TargetOffset = offset;
+                    }
                 } catch (Exception) {
                 }
                 return;