properly dispose of IDisposables in core savestate code, and a few other places

BizHawk.Common/Extensions/IOExtensions.cs

@@ -34,7 +34,7 @@ namespace BizHawk.Common.IOExtensions
 
 		public static string ReadStringUtf8NullTerminated(this BinaryReader br)
 		{
-			var ms = new MemoryStream();
+			using var ms = new MemoryStream();
 			for (;;)
 			{
 				var b = br.ReadByte();

BizHawk.Common/HawkFile.cs

@@ -147,10 +147,8 @@ namespace BizHawk.Common
 		/// </summary>
 		public static bool ExistsAt(string path)
 		{
-			using (var file = new HawkFile(path))
-			{
-				return file.Exists;
-			}
+			using var file = new HawkFile(path);
+			return file.Exists;
 		}
 
 		/// <summary>
@@ -158,20 +156,16 @@ namespace BizHawk.Common
 		/// </summary>
 		public static byte[] ReadAllBytes(string path)
 		{
-			using (var file = new HawkFile(path))
+			using var file = new HawkFile(path);
+			if (!file.Exists)
 			{
-				if (!file.Exists)
-				{
-					throw new FileNotFoundException(path);
-				}
-
-				using (Stream stream = file.GetStream())
-				{
-					var ms = new MemoryStream((int)stream.Length);
-					stream.CopyTo(ms);
-					return ms.GetBuffer();
-				}
+				throw new FileNotFoundException(path);
 			}
+
+			using Stream stream = file.GetStream();
+			using var ms = new MemoryStream((int)stream.Length);
+			stream.CopyTo(ms);
+			return ms.GetBuffer();
 		}
 
 		/// <summary>

BizHawk.Emulation.Cores/Calculator/TI83.IStatable.cs

@@ -7,10 +7,7 @@ namespace BizHawk.Emulation.Cores.Calculators
 {
 	public partial class TI83 : IStatable
 	{
-		public bool BinarySaveStatesPreferred
-		{
-			get { return true; }
-		}
+		public bool BinarySaveStatesPreferred => true;
 
 		public void SaveStateText(TextWriter writer)
 		{
@@ -34,8 +31,8 @@ namespace BizHawk.Emulation.Cores.Calculators
 
 		public byte[] SaveStateBinary()
 		{
-			MemoryStream ms = new MemoryStream();
-			BinaryWriter bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			return ms.ToArray();

BizHawk.Emulation.Cores/Computers/AmstradCPC/AmstradCPC.IStatable.cs

@@ -10,13 +10,9 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
     /// </summary>
     public partial class AmstradCPC : IStatable
     {
+        public bool BinarySaveStatesPreferred => true;
 
-        public bool BinarySaveStatesPreferred
-        {
-            get { return true; }
-        }
-
-        public void SaveStateText(TextWriter writer)
+		public void SaveStateText(TextWriter writer)
         {
             SyncState(new Serializer(writer));
         }
@@ -38,8 +34,8 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 
         public byte[] SaveStateBinary()
         {
-            MemoryStream ms = new MemoryStream();
-            BinaryWriter bw = new BinaryWriter(ms);
+            using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
             SaveStateBinary(bw);
             bw.Flush();
             return ms.ToArray();

BizHawk.Emulation.Cores/Computers/Commodore64/C64.IStatable.cs

@@ -31,13 +31,11 @@ namespace BizHawk.Emulation.Cores.Computers.Commodore64
 
 		public byte[] SaveStateBinary()
 		{
-			using (var ms = new MemoryStream())
-			{
-				var bw = new BinaryWriter(ms);
-				SaveStateBinary(bw);
-				bw.Flush();
-				return ms.ToArray();
-			}
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
+			SaveStateBinary(bw);
+			bw.Flush();
+			return ms.ToArray();
 		}
 
 		private void SyncState(Serializer ser)

BizHawk.Emulation.Cores/Computers/SinclairSpectrum/ZXSpectrum.IStatable.cs

@@ -10,12 +10,9 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
     /// </summary>
     public partial class ZXSpectrum : IStatable
     {
-        public bool BinarySaveStatesPreferred
-        {
-            get { return true; }
-        }
+        public bool BinarySaveStatesPreferred => true;
 
-        public void SaveStateText(TextWriter writer)
+		public void SaveStateText(TextWriter writer)
         {
             SyncState(new Serializer(writer));
         }
@@ -37,8 +34,8 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 
         public byte[] SaveStateBinary()
         {
-            MemoryStream ms = new MemoryStream();
-            BinaryWriter bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
             SaveStateBinary(bw);
             bw.Flush();
             return ms.ToArray();

BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.IStatable.cs

@@ -7,10 +7,7 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
 {
 	public partial class Atari2600 : IStatable
 	{
-		public bool BinarySaveStatesPreferred
-		{
-			get { return true; }
-		}
+		public bool BinarySaveStatesPreferred => true;
 
 		public void SaveStateText(TextWriter writer)
 		{
@@ -34,8 +31,8 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
 
 		public byte[] SaveStateBinary()
 		{
-			var ms = new MemoryStream();
-			var bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			return ms.ToArray();

BizHawk.Emulation.Cores/Consoles/Atari/A7800Hawk/A7800Hawk.IStatable.cs

@@ -31,8 +31,8 @@ namespace BizHawk.Emulation.Cores.Atari.A7800Hawk
 
 		public byte[] SaveStateBinary()
 		{
-			MemoryStream ms = new MemoryStream();
-			BinaryWriter bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			return ms.ToArray();

BizHawk.Emulation.Cores/Consoles/Atari/lynx/Lynx.IStatable.cs

@@ -74,8 +74,8 @@ namespace BizHawk.Emulation.Cores.Atari.Lynx
 
 		public byte[] SaveStateBinary()
 		{
-			var ms = new MemoryStream(_savebuff2, true);
-			var bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream(_savebuff2, true);
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			if (ms.Position != _savebuff2.Length)

BizHawk.Emulation.Cores/Consoles/Atari/lynx/Lynx.cs

@@ -27,8 +27,8 @@ namespace BizHawk.Emulation.Cores.Atari.Lynx
 			byte[] realfile = null;
 
 			{
-				var ms = new MemoryStream(file, false);
-				var br = new BinaryReader(ms);
+				using var ms = new MemoryStream(file, false);
+				using var br = new BinaryReader(ms);
 				string header = Encoding.ASCII.GetString(br.ReadBytes(4));
 				int p0 = br.ReadUInt16();
 				int p1 = br.ReadUInt16();

BizHawk.Emulation.Cores/Consoles/Coleco/ColecoVision.IStatable.cs

@@ -7,10 +7,7 @@ namespace BizHawk.Emulation.Cores.ColecoVision
 {
 	public partial class ColecoVision : IStatable
 	{
-		public bool BinarySaveStatesPreferred
-		{
-			get { return true; }
-		}
+		public bool BinarySaveStatesPreferred => true;
 
 		public void SaveStateText(TextWriter writer)
 		{
@@ -34,8 +31,8 @@ namespace BizHawk.Emulation.Cores.ColecoVision
 
 		public byte[] SaveStateBinary()
 		{
-			MemoryStream ms = new MemoryStream();
-			BinaryWriter bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			return ms.ToArray();
@@ -46,7 +43,7 @@ namespace BizHawk.Emulation.Cores.ColecoVision
 			byte[] core = null;
 			if (ser.IsWriter)
 			{
-				var ms = new MemoryStream();
+				using var ms = new MemoryStream();
 				ms.Close();
 				core = ms.ToArray();
 			}

BizHawk.Emulation.Cores/Consoles/Magnavox/Odyssey2/O2Hawk.IStatable.cs

@@ -31,8 +31,8 @@ namespace BizHawk.Emulation.Cores.Consoles.O2Hawk
 
 		public byte[] SaveStateBinary()
 		{
-			MemoryStream ms = new MemoryStream();
-			BinaryWriter bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			return ms.ToArray();
@@ -43,7 +43,7 @@ namespace BizHawk.Emulation.Cores.Consoles.O2Hawk
 			byte[] core = null;
 			if (ser.IsWriter)
 			{
-				var ms = new MemoryStream();
+				using var ms = new MemoryStream();
 				ms.Close();
 				core = ms.ToArray();
 			}

BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/MGBAHawk.IStatable.cs

@@ -84,8 +84,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBA
 		public byte[] SaveStateBinary()
 		{
 			StartSaveStateBinaryInternal();
-			var ms = new MemoryStream(_savebuff2, true);
-			var bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream(_savebuff2, true);
+			using var bw = new BinaryWriter(ms);
 			FinishSaveStateBinaryInternal(bw);
 			bw.Flush();
 			ms.Close();

BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBHawk.IStatable.cs

@@ -31,8 +31,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
 
 		public byte[] SaveStateBinary()
 		{
-			MemoryStream ms = new MemoryStream();
-			BinaryWriter bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			return ms.ToArray();
@@ -43,7 +43,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
 			byte[] core = null;
 			if (ser.IsWriter)
 			{
-				var ms = new MemoryStream();
+				using var ms = new MemoryStream();
 				ms.Close();
 				core = ms.ToArray();
 			}

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

@@ -9,7 +9,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64
 {
 	public partial class N64 : IStatable
 	{
-		public bool BinarySaveStatesPreferred { get { return true; } }
+		public bool BinarySaveStatesPreferred => true;
 
 		// these functions are all exact copy paste from gambatte.
 		// if something's wrong here, it's probably wrong there too
@@ -82,8 +82,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64
 				SaveStateBinaryPrivateBuff = new byte[lenwant];
 			}
 
-			var ms = new MemoryStream(SaveStateBinaryPrivateBuff);
-			var bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream(SaveStateBinaryPrivateBuff);
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 

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

@@ -658,7 +658,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 			//create the board's rom and vrom
 			if (iNesHeaderInfo != null)
 			{
-				var ms = new MemoryStream(file, false);
+				using var ms = new MemoryStream(file, false);
 				ms.Seek(16, SeekOrigin.Begin); // ines header
 				//pluck the necessary bytes out of the file
 				if (iNesHeaderInfo.trainer_size != 0)

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

@@ -48,8 +48,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 
 		public byte[] SaveStateBinary()
 		{
-			var ms = new MemoryStream();
-			var bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			return ms.ToArray();

BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.IStatable.cs

@@ -3,15 +3,11 @@
 using BizHawk.Common;
 using BizHawk.Emulation.Common;
 
-
 namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 {
 	public partial class SMS : IStatable
 	{
-		public bool BinarySaveStatesPreferred
-		{
-			get { return true; }
-		}
+		public bool BinarySaveStatesPreferred => true;
 
 		public void SaveStateText(TextWriter writer)
 		{
@@ -35,8 +31,8 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 
 		public byte[] SaveStateBinary()
 		{
-			MemoryStream ms = new MemoryStream();
-			BinaryWriter bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			return ms.ToArray();
@@ -47,13 +43,13 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 			byte[] core = null;
 			if (ser.IsWriter)
 			{
-				var ms = new MemoryStream();
+				using var ms = new MemoryStream();
 				ms.Close();
 				core = ms.ToArray();
 			}
 			Cpu.SyncState(ser);
 
-			ser.BeginSection(nameof(SMS));			
+			ser.BeginSection(nameof(SMS));
 			Vdp.SyncState(ser);
 			PSG.SyncState(ser);
 			ser.Sync("RAM", ref SystemRam, false);

BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.IStatable.cs

@@ -8,10 +8,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 {
 	public partial class GPGX : IStatable
 	{
-		public bool BinarySaveStatesPreferred
-		{
-			get { return true; }
-		}
+		public bool BinarySaveStatesPreferred => true;
 
 		public void SaveStateText(TextWriter writer)
 		{
@@ -59,8 +56,8 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 
 		public byte[] SaveStateBinary()
 		{
-			var ms = new MemoryStream();
-			var bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			ms.Close();

BizHawk.Emulation.Cores/Consoles/Sony/PSX/Octoshock.cs

@@ -1181,8 +1181,8 @@ namespace BizHawk.Emulation.Cores.Sony.PSX
 		public byte[] SaveStateBinary()
 		{
 			//this are objectionable shenanigans, but theyre required to get the extra info in the stream. we need a better approach.
-			var ms = new MemoryStream(savebuff2, true);
-			var bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream(savebuff2, true);
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			if (ms.Position != savebuff2.Length)
@@ -1191,10 +1191,7 @@ namespace BizHawk.Emulation.Cores.Sony.PSX
 			return savebuff2;
 		}
 
-		public bool BinarySaveStatesPreferred
-		{
-			get { return true; }
-		}
+		public bool BinarySaveStatesPreferred => true;
 
 		#endregion
 

BizHawk.Emulation.Cores/Consoles/WonderSwan/WonderSwan.IStatable.cs

@@ -16,7 +16,7 @@ namespace BizHawk.Emulation.Cores.WonderSwan
 			savebuff2 = new byte[savebuff.Length + 13];
 		}
 
-		JsonSerializer ser = new JsonSerializer() { Formatting = Formatting.Indented };
+		JsonSerializer ser = new JsonSerializer { Formatting = Formatting.Indented };
 
 		[StructLayout(LayoutKind.Sequential)]
 		class TextStateData
@@ -88,8 +88,8 @@ namespace BizHawk.Emulation.Cores.WonderSwan
 
 		public byte[] SaveStateBinary()
 		{
-			var ms = new MemoryStream(savebuff2, true);
-			var bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream(savebuff2, true);
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			if (ms.Position != savebuff2.Length)
@@ -98,9 +98,6 @@ namespace BizHawk.Emulation.Cores.WonderSwan
 			return savebuff2;
 		}
 
-		public bool BinarySaveStatesPreferred
-		{
-			get { return true; }
-		}
+		public bool BinarySaveStatesPreferred => true;
 	}
 }

BizHawk.Emulation.Cores/Waterbox/WaterboxCore.cs

@@ -303,8 +303,8 @@ namespace BizHawk.Emulation.Cores.Waterbox
 
 		public byte[] SaveStateBinary()
 		{
-			var ms = new MemoryStream();
-			var bw = new BinaryWriter(ms);
+			using var ms = new MemoryStream();
+			using var bw = new BinaryWriter(ms);
 			SaveStateBinary(bw);
 			bw.Flush();
 			ms.Close();