N64 - wire of a disassembler, doesn't look like it works correctly, but at least the plumbing is done

BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj

@@ -392,6 +392,9 @@
     <Compile Include="Consoles\Nintendo\N64\N64.IDebuggable.cs">
       <DependentUpon>N64.cs</DependentUpon>
     </Compile>
+    <Compile Include="Consoles\Nintendo\N64\N64.IDisassemblable.cs">
+        <DependentUpon>N64.cs</DependentUpon>
+    </Compile>
     <Compile Include="Consoles\Nintendo\N64\N64.IInputPollable.cs">
       <DependentUpon>N64.cs</DependentUpon>
     </Compile>

BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.IDisassemblable.cs

@@ -0,0 +1,41 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+
+using BizHawk.Emulation.Common;
+
+namespace BizHawk.Emulation.Cores.Nintendo.N64
+{
+	public partial class N64 : IDisassemblable
+	{
+		public string Cpu
+		{
+			get { return "R4300"; }
+			set { }
+		}
+
+		public IEnumerable<string> AvailableCpus
+		{
+			get
+			{
+				yield return "R4300";
+			}
+		}
+
+		public string PCRegisterName
+		{
+			get { return "PC"; }
+		}
+
+		public string Disassemble(MemoryDomain m, uint addr, out int length)
+		{
+			length = 4; // TODO: is this right?
+			var instruction = m.PeekWord(addr, true);
+
+			var result = api.m64p_decode_op((uint)instruction, (int)addr);
+			var strResult = Marshal.PtrToStringAnsi(result);
+
+			return strResult;
+		}
+	}
+}

BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.cs

@@ -19,7 +19,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64
 		portedUrl: "https://code.google.com/p/mupen64plus/"
 		)]
 	[ServiceNotApplicable(typeof(IDriveLight))]
-	public partial class N64 : IEmulator, ISaveRam, IDebuggable, IStatable, IInputPollable,
+	public partial class N64 : IEmulator, ISaveRam, IDebuggable, IStatable, IInputPollable, IDisassemblable,
 		ISettable<N64Settings, N64SyncSettings>
 	{
 		private readonly N64Input _inputProvider;

BizHawk.Emulation.Cores/Consoles/Nintendo/N64/NativeAPI/mupen64plusCoreApi.cs

@@ -265,6 +265,10 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64.NativeApi
 		delegate m64p_error CoreDoCommandRenderCallback(m64p_command Command, int ParamInt, RenderCallback ParamPtr);
 		CoreDoCommandRenderCallback m64pCoreDoCommandRenderCallback;
 
+		[UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+		public delegate IntPtr biz_r4300_decode_op(uint instr, int counter);
+		public biz_r4300_decode_op m64p_decode_op; 
+
 		/// <summary>
 		/// Reads from the "system bus"
 		/// </summary>
@@ -499,6 +503,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64.NativeApi
 
 			m64p_read_memory_8 = (biz_read_memory)Marshal.GetDelegateForFunctionPointer(GetProcAddress(CoreDll, "biz_read_memory"), typeof(biz_read_memory));
 			m64p_write_memory_8 = (biz_write_memory)Marshal.GetDelegateForFunctionPointer(GetProcAddress(CoreDll, "biz_write_memory"), typeof(biz_write_memory));
+
+			m64p_decode_op = (biz_r4300_decode_op)Marshal.GetDelegateForFunctionPointer(GetProcAddress(CoreDll, "biz_r4300_decode_op"), typeof(biz_r4300_decode_op));
 		}
 
 		/// <summary>

libmupen64plus/mupen64plus-core/src/debugger/dbg_decoder.c

@@ -797,6 +797,30 @@ r4k_disassemble_split_quick ( uint32_t instruction,
     );
 }
 
+#include "api/m64p_types.h"
+
+EXPORT char* CALL biz_r4300_decode_op(uint32 instr, int counter)
+{
+	char * _final;
+	char * _op, * _args;
+    
+    _op = NULL;
+    _args = NULL;
+	_final = NULL;
+    
+    r4k_disassemble_split_quick(
+        instr,
+        counter,
+        &_op,
+        &_args
+    );
+
+
+    //free( _op );
+	strcat(_op, " ");
+	strcat(_op, _args);
+	return _op;
+}
 
 //=-=-=-=-=-=-=-=-=-=-=-=-=-=-=[ DECODE_OP ]=-=-=-=-=-=-=-=-=-=-=-=-=-=-=[//
 
@@ -819,4 +843,3 @@ void r4300_decode_op ( uint32 instr, char * opcode, char * arguments, int counte
     
     free( _op );
 }
-