snes-fix bugs caused by breakpoints leaving emulator state unstable (most noticeable when taking savestates)

BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesApi.cs

@@ -220,11 +220,6 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 				//this approach is slower than having one big case. but, its easier to manage. once the code is stable, someone could clean it up (probably creating a delegate table would be best)
 				if (Handle_SIG(msg)) continue;
 				if (Handle_BRK(msg)) continue;
-				switch (msg)
-				{
-					case eMessage.eMessage_Complete:
-						return;
-				}
 			}
 		} 
 
@@ -260,7 +255,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 
 		public void SPECIAL_Resume()
 		{
-			WritePipeMessage(eMessage.eMessage_CMD_run);
+			WritePipeMessage(eMessage.eMessage_ResumeAfterBRK);
 		}
 	}
 

BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesApi_Enums.cs

@@ -9,10 +9,11 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 		public enum eMessage : int
 		{
 			eMessage_NotSet,
-			eMessage_Complete,
+			
 			eMessage_SetBuffer,
 			eMessage_BeginBufferIO,
 			eMessage_EndBufferIO,
+			eMessage_ResumeAfterBRK,
 
 			eMessage_QUERY_library_id,
 			eMessage_QUERY_library_revision_major,

BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesApi_QUERY.cs

@@ -77,7 +77,6 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 			{
 				WritePipeMessage(eMessage.eMessage_QUERY_serialize_size);
 				int ret = brPipe.ReadInt32();
-				Console.WriteLine("eMessage.eMessage_QUERY_serialize_size: " + ret);
 				if (ret > 100)
 				{
 					return ret;

BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesApi_SIG.cs

@@ -77,7 +77,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 							scanlineStart(line);
 
 						//we have to notify the unmanaged process that we're done peeking thruogh its memory and whatnot so it can proceed with emulation
-						WritePipeMessage(eMessage.eMessage_Complete);
+						//HUM??????????? BRK_COMPLETE???? SCANLINE CB NEEDS RE-EVALUATING
+						WritePipeMessage(eMessage.eMessage_BRK_Complete);
 						break;
 					}
 				case eMessage.eMessage_SIG_path_request:

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

@@ -578,7 +578,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 			api.QUERY_set_layer_enable(4, 2, Settings.ShowOBJ_2);
 			api.QUERY_set_layer_enable(4, 3, Settings.ShowOBJ_3);
 
-			RefreshMemoryCallbacks();
+			RefreshMemoryCallbacks(false);
 
 			//apparently this is one frame?
 			timeFrameCounter++;
@@ -596,12 +596,12 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 			api.EndBufferIO();
 		}
 
-		void RefreshMemoryCallbacks()
+		void RefreshMemoryCallbacks(bool suppress)
 		{
 			var mcs = CoreComm.MemoryCallbackSystem;
-			api.QUERY_set_state_hook_exec(mcs.HasExecutes);
+			api.QUERY_set_state_hook_exec(!suppress && mcs.HasExecutes);
-			api.QUERY_set_state_hook_read(mcs.HasReads);
+			api.QUERY_set_state_hook_read(!suppress && mcs.HasReads);
-			api.QUERY_set_state_hook_write(mcs.HasWrites);
+			api.QUERY_set_state_hook_write(!suppress && mcs.HasWrites);
 		}
 
 		public DisplayType DisplayType
@@ -927,6 +927,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 			fixed (byte* pbuf = &data[0])
 				api.CMD_unserialize(new IntPtr(pbuf), size);
 		}
+
+
 		/// <summary>
 		/// handle the unmanaged part of savestating
 		/// </summary>

libsnes/bsnes/target-libsnes/libsnes_pwrap.cpp

@@ -10,10 +10,10 @@
 //TODO - factor out modular components (ringbuffer and the like)
 
 //types of messages:
-//cmd: frontend->core: "command to core" a command from the frontend which causes emulation to proceed. when sending a command, the frontend should wait for an eMessage_brk_complete before proceeding, although a debugger might proceed after any BRK
+//cmd: frontend->core: "command to core" a command from the frontend which causes emulation to proceed. when sending a command, the frontend should wait for an eMessage_BRK_Complete before proceeding, although a debugger might proceed after any BRK
-//query: frontend->core: "query to core" a query from the frontend which can (and should) be satisfied immediately by the core but which does not result in emulation processes
+//query: frontend->core: "query to core" a query from the frontend which can (and should) be satisfied immediately by the core but which does not result in emulation processes (notably, nothing resembling a CMD and nothing which can trigger a BRK)
 //sig: core->frontend: "core signal" a synchronous operation called from the emulation process which the frontend should handle immediately without issuing any calls into the core
-//brk: core->frontend: "core break" the emulation process has suspended. the core is free to do whatever it wishes.
+//brk: core->frontend: "core break" the emulation process has suspended. the frontend is free to do whatever it wishes.
 //(and there are other assorted special messages...)
 
 
@@ -41,11 +41,11 @@ typedef uint16 u16;
 enum eMessage : int32
 {
 	eMessage_NotSet,
-	eMessage_Complete,
 
 	eMessage_SetBuffer,
 	eMessage_BeginBufferIO,
 	eMessage_EndBufferIO,
+	eMessage_ResumeAfterBRK, //resumes execution of the core, after a BRK. no change to current CMD
 
 	eMessage_QUERY_library_id,
 	eMessage_QUERY_library_revision_major,
@@ -111,7 +111,7 @@ enum eEmulationExitReason
 	eEmulationExitReason_NotSet,
 	eEmulationExitReason_BRK,
 	eEmulationExitReason_SIG,
-	eEmulationExitReason_Complete, //TODO rename CMD_Complete
+	eEmulationExitReason_CMD_Complete,
 };
 
 enum eEmulationCallback
@@ -728,7 +728,7 @@ bool Handle_QUERY(eMessage msg)
 			char* dstbuf = ReadPipeSharedPtr();
 			uint8_t* srcbuf = snes_get_memory_data(id);
 			memcpy(dstbuf,srcbuf,snes_get_memory_size(id));
-			WritePipe(eMessage_Complete);
+			WritePipe(eMessage_BRK_Complete);
 			break;
 		}
 
@@ -875,6 +875,14 @@ bool Handle_QUERY(eMessage msg)
 
 bool Handle_CMD(eMessage msg)
 {
+	if(msg == eMessage_ResumeAfterBRK)
+	{
+		//careful! dont switch back to co_emu, we were in another cothread probably when the BRK happened.
+		//i'm not sure its completely safe to be returning to co_emu below in the normal CMD handler, either...
+		co_switch(co_emu_suspended);
+		return true;		
+	}
+	
 	if(msg<=eMessage_CMD_FIRST || msg>=eMessage_CMD_LAST) return false;
 
 	s_EmulationControl.command = msg;
@@ -911,11 +919,11 @@ TOP:
 		case eEmulationExitReason_NotSet:
 			goto HANDLEMESSAGES;
 		
-		case eEmulationExitReason_Complete:
+		case eEmulationExitReason_CMD_Complete:
-			//printf("eEmulationExitReason_Complete (command:%d)\n",s_EmulationControl.command);
+			//printf("eEmulationExitReason_CMD_Complete (command:%d)\n",s_EmulationControl.command);
 			//MessageBox(0,"ZING","ZING",MB_OK);
 			//printf("WRITING COMPLETE\n");
-			WritePipe(eMessage_Complete);
+			WritePipe(eMessage_BRK_Complete);
 			
 			//special post-completion messages (return values)
 			switch(s_EmulationControl.command)
@@ -1025,7 +1033,7 @@ HANDLEMESSAGES:
 
 		switch(msg)
 		{
-		case eMessage_Complete:
+		case eMessage_BRK_Complete:
 			return;
 		
 		case eMessage_SetBuffer:
@@ -1172,7 +1180,7 @@ void emuthread()
 			break;
 		}
 
-		s_EmulationControl.exitReason = eEmulationExitReason_Complete;
+		s_EmulationControl.exitReason = eEmulationExitReason_CMD_Complete;
 		SETCONTROL;
 	}
 }