sameboy: SAVERAMS

BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/LibSameboy.cs

@@ -42,5 +42,14 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.Gameboy
 
 		[BizImport(CC)]
 		public abstract byte GetIoReg(byte port);
+
+		[BizImport(CC)]
+		public abstract void PutSaveRam();
+
+		[BizImport(CC)]
+		public abstract void GetSaveRam();
+
+		[BizImport(CC)]
+		public abstract bool HasSaveRam();
 	}
 }

BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Sameboy.cs

@@ -13,7 +13,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.Gameboy
 {
 	[Core("SameBoy", "LIJI32", true, false, "efc11783c7fb6da66e1dd084e41ba6a85c0bd17e",
 		"https://sameboy.github.io/", false)]
-	public class Sameboy : WaterboxCore, IGameboyCommon
+	public class Sameboy : WaterboxCore, IGameboyCommon, ISaveRam
 	{
 		/// <summary>
 		/// the nominal length of one frame
@@ -147,6 +147,26 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.Gameboy
 
 		#endregion
 
+		#region ISaveram
+
+		public new bool SaveRamModified => _core.HasSaveRam();
+
+		public new byte[] CloneSaveRam()
+		{
+			_exe.AddTransientFile(null, "save.ram");
+			_core.GetSaveRam();
+			return _exe.RemoveTransientFile("save.ram");
+		}
+
+		public new void StoreSaveRam(byte[] data)
+		{
+			_exe.AddReadonlyFile(data, "save.ram");
+			_core.PutSaveRam();
+			_exe.RemoveReadonlyFile("save.ram");
+		}
+
+		#endregion
+
 		protected override LibWaterboxCore.FrameInfo FrameAdvancePrep(IController controller, bool render, bool rendersound)
 		{
 			return new LibSameboy.FrameInfo

BizHawk.Emulation.Cores/Waterbox/PeRunner.cs

@@ -308,6 +308,68 @@ namespace BizHawk.Emulation.Cores.Waterbox
 				}
 			}
 
+			private class TransientFile : IFileObject
+			{
+				private bool _inUse = false;
+				public string Name { get; }
+				public Stream Stream { get; }
+				public bool Close()
+				{
+					if (_inUse)
+					{
+						_inUse = false;
+						return true;
+					}
+					else
+					{
+						return false;
+					}
+				}
+
+				public bool Open(FileAccess access)
+				{
+					if (_inUse)
+					{
+						return false;
+					}
+					else
+					{
+						// TODO: if access != RW, the resultant handle lets you do those all anyway
+						_inUse = true;
+						Stream.Position = 0;
+						return true;
+					}
+				}
+
+				public void LoadStateBinary(BinaryReader br)
+				{
+					throw new InvalidOperationException("Internal savestate error!");
+				}
+
+				public void SaveStateBinary(BinaryWriter bw)
+				{
+					throw new InvalidOperationException("Transient files cannot be savestated!");
+				}
+
+				public TransientFile(byte[] data, string name)
+				{
+					Stream = new MemoryStream();
+					Name = name;
+					if (data != null)
+					{
+						Stream.Write(data, 0, data.Length);
+						Stream.Position = 0;
+					}
+				}
+
+				public byte[] GetContents()
+				{
+					if (_inUse)
+						throw new InvalidOperationException();
+					return ((MemoryStream)Stream).ToArray();
+				}
+			}
+
 			private readonly List<IFileObject> _openFiles = new List<IFileObject>();
 			private readonly Dictionary<string, IFileObject> _availableFiles = new Dictionary<string, IFileObject>();
 
@@ -697,6 +759,21 @@ namespace BizHawk.Emulation.Cores.Waterbox
 				}
 			}
 
+
+			private T RemoveFileInternal<T>(string name)
+				where T : IFileObject
+			{
+				IFileObject o;
+				if (!_availableFiles.TryGetValue(name, out o))
+					throw new InvalidOperationException("File was never registered!");
+				if (o.GetType() != typeof(T))
+					throw new InvalidOperationException("Object was not a the right kind of file");
+				if (_openFiles.Contains(o))
+					throw new InvalidOperationException("Core never closed the file!");
+				_availableFiles.Remove(name);
+				return (T)o;
+			}
+
 			public void AddReadonlyFile(byte[] data, string name)
 			{
 				_availableFiles.Add(name, new ReadonlyFirmware(data, name));
@@ -704,15 +781,16 @@ namespace BizHawk.Emulation.Cores.Waterbox
 
 			public void RemoveReadonlyFile(string name)
 			{
-				IFileObject o;
-				if (!_availableFiles.TryGetValue(name, out o))
-					throw new InvalidOperationException("Firmware was never registered!");
-				var f = o as ReadonlyFirmware;
-				if (f == null)
-					throw new InvalidOperationException("Object was not a firmware!");
-				if (_openFiles.Contains(o))
-					throw new InvalidOperationException("Core never closed the firmware!");
-				_availableFiles.Remove(name);
+				RemoveFileInternal<ReadonlyFirmware>(name);
+			}
+
+			public void AddTransientFile(byte[] data, string name)
+			{
+				_availableFiles.Add(name, new TransientFile(data, name));
+			}
+			public byte[] RemoveTransientFile(string name)
+			{
+				return RemoveFileInternal<TransientFile>(name).GetContents();
 			}
 		}
 
@@ -1090,6 +1168,24 @@ namespace BizHawk.Emulation.Cores.Waterbox
 			_syscalls.RemoveReadonlyFile(name);
 		}
 
+		/// <summary>
+		/// Add a transient file that will appear to the waterbox core's libc.  The file will be readable
+		/// and writable.  Any attempt to save state while the file is loaded will fail.
+		/// </summary>
+		public void AddTransientFile(byte[] data, string name)
+		{
+			_syscalls.AddTransientFile(data, name); // don't need to clone data, as it's used at init only
+		}
+
+		/// <summary>
+		/// Remove a file previously added by AddTransientFile
+		/// </summary>
+		/// <returns>The state of the file when it was removed</returns>
+		public byte[] RemoveTransientFile(string name)
+		{
+			return _syscalls.RemoveTransientFile(name);
+		}
+
 		public void SaveStateBinary(BinaryWriter bw)
 		{
 			bw.Write(_createstamp);

waterbox/sameboy/bizhawk.cpp

@@ -15,7 +15,7 @@ extern "C" {
 static GB_gameboy_t GB;
 
 static uint32_t GBPixels[160 * 144];
-static uint32_t* CurrentFramebuffer;
+static uint32_t *CurrentFramebuffer;
 static bool sgb;
 static void VBlankCallback(GB_gameboy_t *gb)
 {
@@ -94,7 +94,7 @@ static void SgbSampleCallback(int16_t sl, int16_t sr, uint64_t clock)
 	sample_sgb.right = sr;
 }
 
-ECL_EXPORT bool Init(bool cgb, const uint8_t* spc, int spclen)
+ECL_EXPORT bool Init(bool cgb, const uint8_t *spc, int spclen)
 {
 	if (spc)
 	{
@@ -145,7 +145,7 @@ ECL_EXPORT void FrameAdvance(MyFrameInfo &f)
 {
 	if (sgb)
 	{
-		sgb_set_controller_data((uint8_t*)&f.Keys);
+		sgb_set_controller_data((uint8_t *)&f.Keys);
 	}
 	else
 	{
@@ -225,6 +225,25 @@ ECL_EXPORT uint8_t GetIoReg(uint8_t port)
 	return GB.io_registers[port];
 }
 
+ECL_EXPORT void PutSaveRam()
+{
+	GB_load_battery(&GB, "save.ram");
+}
+
+ECL_EXPORT void GetSaveRam()
+{
+	GB_save_battery(&GB, "save.ram");
+}
+
+ECL_EXPORT bool HasSaveRam()
+{
+	if (!GB.cartridge_type->has_battery)
+		return false; // Nothing to save.
+	if (GB.mbc_ram_size == 0 && !GB.cartridge_type->has_rtc)
+		return false; /* Claims to have battery, but has no RAM or RTC */
+	return true;
+}
+
 int main()
 {
 	return 0;