snes-try and determine whether game is snes based on libsnes's internal heuristics, and use .SFC for it anyway

BizHawk.Emulation/Consoles/Nintendo/SNES/LibsnesCore.cs

@@ -8,6 +8,7 @@ using System.Runtime.InteropServices;
 
 namespace BizHawk.Emulation.Consoles.Nintendo.SNES
 {
+	//TODO - wrap around some kind of library-accessing interface so that it doesnt malfunction if the dll is unavailable
 	public unsafe static class LibsnesDll
 	{
 		[DllImport("snes.dll", CallingConvention = CallingConvention.Cdecl)]
@@ -52,6 +53,12 @@ namespace BizHawk.Emulation.Consoles.Nintendo.SNES
 		[DllImport("snes.dll", CallingConvention = CallingConvention.Cdecl)]
 		public static extern void snes_set_audio_sample(snes_audio_sample_t audio_sample);
 
+		[DllImport("snes.dll", CallingConvention = CallingConvention.Cdecl)]
+		[return: MarshalAs(UnmanagedType.U1)]
+		public static extern bool snes_check_cartridge(
+			[MarshalAs(UnmanagedType.LPArray)] byte[] rom_data,
+			int rom_size);
+
 		public enum Device : uint
 		{
 			None,

BizHawk.MultiClient/MainForm.cs

@@ -1309,20 +1309,31 @@ namespace BizHawk.MultiClient
 						rom = new RomGame(file);
 						game = rom.GameInfo;
 
+						//use some heuristics to figure out what game type it might be
 						if (game.NotInDatabase)
 						{
-							//try to load based on extension
-							switch (file.Extension.ToUpper())
+							//try asking the snes core 
+							if (LibsnesDll.snes_check_cartridge(rom.FileData, rom.FileData.Length))
+								game.System = "SNES";
+							else
 							{
-								case ".SMC":
-									nextEmulator = new BizHawk.Emulation.Consoles.Nintendo.SNES.LibsnesCore(rom.FileData);
-									game.System = "SNES";
-									break;
+								//try and use the extension
+								switch (file.Extension.ToUpper())
+								{
+									case ".SFC":
+									case ".SMC":
+										game.System = "SNES";
+										break;
+								}
 							}
 						}
 
 						switch (game.System)
 						{
+							case "SNES":
+									nextEmulator = new LibsnesCore(rom.FileData);
+									game.System = "SNES";
+								break;
 							case "SMS":
 							case "SG":
 								if (Global.Config.SmsEnableFM) game.AddOption("UseFM");
@@ -1380,10 +1391,10 @@ namespace BizHawk.MultiClient
 								SMS c = new SMS(game, rom.RomData);//new ColecoVision(game, rom.FileData);
 								nextEmulator = c;
 								break;
-                            case "INTV":
-                                Intellivision intv = new Intellivision(game, rom.RomData);
-                                nextEmulator = intv;
-                                break;
+							case "INTV":
+								Intellivision intv = new Intellivision(game, rom.RomData);
+								nextEmulator = intv;
+								break;
 						}
 					}
 

libsnes/bsnes/target-libsnes/libsnes.cpp

@@ -209,6 +209,14 @@ void snes_cheat_set(unsigned index, bool enable, const char *code) {
   SNES::cheat.synchronize();
 }
 
+//zeromus additions
+bool snes_check_cartridge(const uint8_t *rom_data, unsigned rom_size)
+{
+	//tries to determine whether this rom is a snes rom
+	SnesCartridge temp(rom_data, rom_size);
+	return temp.type != SnesCartridge::TypeUnknown && temp.type != SnesCartridge::TypeGameBoy;
+}
+
 bool snes_load_cartridge_normal(
   const char *rom_xml, const uint8_t *rom_data, unsigned rom_size
 ) {

libsnes/bsnes/target-libsnes/libsnes.hpp

@@ -128,7 +128,8 @@ bool snes_get_region(void);
 uint8_t* snes_get_memory_data(unsigned id);
 unsigned snes_get_memory_size(unsigned id);
 
-//zeromus additions (TBD)
+//zeromus additions
+bool snes_check_cartridge(const uint8_t *rom_data, unsigned rom_size);
 
 #ifdef __cplusplus
 }