From 00f46b0e7dc212f46c0b3836d3384a9ba1f9ea39 Mon Sep 17 00:00:00 2001
From: Asnivor <coding@asnitech.co.uk>
Date: Thu, 26 Apr 2018 15:00:54 +0100
Subject: [PATCH] Fix edge-case issue where non-rom games have a header offset
 detected in RomGame.cs (leading to system detection issues further down the
 line)

---
 BizHawk.Client.Common/RomGame.cs              | 7 +++++++
 BizHawk.Emulation.Common/Database/Database.cs | 5 +++--
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/BizHawk.Client.Common/RomGame.cs b/BizHawk.Client.Common/RomGame.cs
index a30e3b64c4..13eaf5b94f 100644
--- a/BizHawk.Client.Common/RomGame.cs
+++ b/BizHawk.Client.Common/RomGame.cs
@@ -66,6 +66,13 @@ namespace BizHawk.Client.Common
 			{
 				RomData = FileData;
 			}
+            else if (file.Extension == ".DSK" || file.Extension == ".TAP" || file.Extension == ".TZX")
+            {
+                // these are not roms. unforunately if treated as such there are certain edge-cases
+                // where a header offset is detected. This should mitigate this issue until a cleaner solution is found 
+                // (-Asnivor)
+                RomData = FileData;
+            }
 			else
 			{
 				// if there was a header offset, read the whole file into FileData and then copy it into RomData (this is unfortunate, in case RomData isnt needed)
diff --git a/BizHawk.Emulation.Common/Database/Database.cs b/BizHawk.Emulation.Common/Database/Database.cs
index 8f0af8194d..5f37e91711 100644
--- a/BizHawk.Emulation.Common/Database/Database.cs
+++ b/BizHawk.Emulation.Common/Database/Database.cs
@@ -341,8 +341,9 @@ namespace BizHawk.Emulation.Common
 
 				case ".DSK":
                     byte[] head2 = romData.Take(20).ToArray();
-                    if (System.Text.Encoding.Default.GetString(head2).ToUpper().Contains("EXTENDED CPC DSK") ||
-                        System.Text.Encoding.Default.GetString(head2).ToUpper().Contains("MV - CPCEMU"))
+                    string ident = System.Text.Encoding.Default.GetString(head2);
+                    if (ident.ToUpper().Contains("EXTENDED CPC DSK") ||
+                        ident.ToUpper().Contains("MV - CPCEMU"))
                         game.System = "ZXSpectrum";
                     else
                         game.System = "AppleII";