From 685de44861186d7bebbacd456886e99bd1fa38f4 Mon Sep 17 00:00:00 2001
From: alyosha-tas <alexei.f.k@gmail.com>
Date: Thu, 2 Mar 2017 20:05:20 -0500
Subject: [PATCH] QuickNES fix Ms. Pac Man (Tengen)

Really it's the iNES header that is wrong, but QuickNES doesn't know this so adjust the file before sending it to QuickNES to boot.
I imagine there are other games that would be fixed in this manner and thus run in QuickNES.
---
 .../Consoles/Nintendo/QuickNES/QuickNES.cs    | 30 ++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/QuickNES/QuickNES.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/QuickNES/QuickNES.cs
index f44285a511..cd6dd1a574 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/QuickNES/QuickNES.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/QuickNES/QuickNES.cs
@@ -37,12 +37,14 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.QuickNES
 			{
 				ServiceProvider = new BasicServiceProvider(this);
 				CoreComm = comm;
-
+				
 				Context = QN.qn_new();
 				if (Context == IntPtr.Zero)
 					throw new InvalidOperationException("qn_new() returned NULL");
 				try
 				{
+
+					file = fix_ines_header(file);
 					unsafe
 					{
 						fixed (byte* p = file)
@@ -52,6 +54,8 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.QuickNES
 						}
 					}
 
+					
+
 					InitSaveRamBuff();
 					InitSaveStateBuff();
 					InitAudio();
@@ -313,6 +317,30 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.QuickNES
 				throw new ObjectDisposedException(GetType().Name);
 		}
 
+		// Fix some incorrect ines header entries that QuickNES uses to load games.
+		// we need to do this from the raw file since QuickNES hasn't had time to process it yet.
+		byte[] fix_ines_header(byte[] file)
+		{
+			string sha1 = BizHawk.Common.BufferExtensions.BufferExtensions.HashSHA1(file);
+			bool log_it = false;
+
+			Console.WriteLine(sha1);
+			if (sha1== "93010514AA1300499ABC8F145D6ABCDBF3084090") // Ms. Pac Man (Tengen) [!]
+			{
+				file[6] &= 0xFE;
+				log_it = true;
+			}
+
+			if (log_it)
+			{
+				Console.WriteLine("iNES header error detected, adjusting settings...");
+				Console.WriteLine(sha1);
+			}
+
+			return file;
+
+		}
+
 		#region Blacklist
 
 		// These games are known to not work in quicknes but quicknes thinks it can run them, bail out if one of these is loaded