CoreFoundation: consistently use nuint instead of mixed (u)long usage.

This also fixes a few P/Invokes that were incorrectly bound with (u)long instead of nuint.

src/CoreFoundation/DispatchData.cs

@@ -51,7 +51,7 @@ namespace CoreFoundation {
 		}
 
 		[DllImport (Constants.libcLibrary)]
-		extern static IntPtr dispatch_data_create (IntPtr buffer, IntPtr size, IntPtr dispatchQueue, IntPtr destructor);
+		extern static IntPtr dispatch_data_create (IntPtr buffer, nuint size, IntPtr dispatchQueue, IntPtr destructor);
 
 		//
 		// This constructor will do it for now, but we should support a constructor
@@ -63,7 +63,7 @@ namespace CoreFoundation {
 				throw new ArgumentNullException (nameof (buffer));
 			var b = Marshal.AllocHGlobal (buffer.Length);
 			Marshal.Copy (buffer, 0, b, buffer.Length);
-			var dd = dispatch_data_create (b, (IntPtr) buffer.Length, IntPtr.Zero, destructor: free);
+			var dd = dispatch_data_create (b, (nuint) buffer.Length, IntPtr.Zero, destructor: free);
 			return new DispatchData (dd, owns: true);
 		}
 
@@ -80,30 +80,30 @@ namespace CoreFoundation {
 
 			var b = Marshal.AllocHGlobal (length);
 			Marshal.Copy (buffer, start, b, length);
-			var dd = dispatch_data_create (b, (IntPtr) length, IntPtr.Zero, destructor: free);
+			var dd = dispatch_data_create (b, (nuint) length, IntPtr.Zero, destructor: free);
 			return new DispatchData (dd, owns: true);
 		}
 
 		//
 		// This will create a DispatchData by making a copy of the provided buffer
 		//
-		public static DispatchData FromBuffer (IntPtr buffer, ulong size)
+		public static DispatchData FromBuffer (IntPtr buffer, nuint size)
 		{
 			if (buffer == null)
 				throw new ArgumentNullException (nameof (buffer));
-			var dd = dispatch_data_create (buffer, (IntPtr) size, IntPtr.Zero, destructor: IntPtr.Zero);
+			var dd = dispatch_data_create (buffer, (nuint) size, IntPtr.Zero, destructor: IntPtr.Zero);
 			return new DispatchData (dd, owns: true);
 		}
 
 		[DllImport (Constants.libcLibrary)]
-		extern static IntPtr dispatch_data_get_size (IntPtr handle);
+		extern static nuint dispatch_data_get_size (IntPtr handle);
 
-		public long Size => (long) dispatch_data_get_size (handle);
+		public nuint Size => dispatch_data_get_size (handle);
 
 		[DllImport (Constants.libcLibrary)]
-		extern static IntPtr dispatch_data_create_map (IntPtr handle, out IntPtr bufferPtr, out ulong size);
+		extern static IntPtr dispatch_data_create_map (IntPtr handle, out IntPtr bufferPtr, out nuint size);
 
-		public DispatchData CreateMap (out IntPtr bufferPtr, out ulong size)
+		public DispatchData CreateMap (out IntPtr bufferPtr, out nuint size)
 		{
 			var nh = dispatch_data_create_map (handle, out bufferPtr, out size);
 			return new DispatchData (nh, owns: true);
@@ -123,9 +123,9 @@ namespace CoreFoundation {
 		}
 
 		[DllImport (Constants.libcLibrary)]
-		extern static IntPtr dispatch_data_create_subrange (IntPtr handle, ulong offset, ulong size);
+		extern static IntPtr dispatch_data_create_subrange (IntPtr handle, nuint offset, nuint size);
 
-		public DispatchData CreateSubrange (ulong offset, ulong size)
+		public DispatchData CreateSubrange (nuint offset, nuint size)
 		{
 			return new DispatchData (dispatch_data_create_subrange (handle, offset, size), owns: true);
 		}

src/CoreFoundation/DispatchIO.cs

@@ -65,13 +65,13 @@ namespace CoreFoundation {
 		}
 
 		[DllImport (Constants.libcLibrary)]
-		extern static void dispatch_read (int fd, ulong length, IntPtr dispatchQueue, IntPtr block);
+		extern static void dispatch_read (int fd, nuint length, IntPtr dispatchQueue, IntPtr block);
 
 		//
-		// if size == ULong.MaxValue, reads as much data as is available
+		// if size == nuint.MaxValue, reads as much data as is available
 		//
 		[BindingImpl (BindingImplOptions.Optimizable)]
-		public static void Read (int fd, ulong size, DispatchQueue dispatchQueue, DispatchIOHandler handler)
+		public static void Read (int fd, nuint size, DispatchQueue dispatchQueue, DispatchIOHandler handler)
 		{
 			if (handler == null)
 				throw new ArgumentNullException (nameof (handler));

src/Network/NWConnection.cs

@@ -32,7 +32,7 @@ namespace Network {
 	// be present, and *also* the error will be set, indicating that some data was
 	// retrieved, before the error was raised.
 	//
-	public delegate void NWConnectionReceiveCompletion (IntPtr data, ulong dataSize, NWContentContext context, bool isComplete, NWError error);
+	public delegate void NWConnectionReceiveCompletion (IntPtr data, nuint dataSize, NWContentContext context, bool isComplete, NWError error);
 
 	//
 	// Signature for a method invoked on data received, same as NWConnectionReceiveCompletion,
@@ -259,7 +259,7 @@ namespace Network {
 			if (del != null) {
 				DispatchData dispatchData = null, dataCopy = null;
 				IntPtr bufferAddress = IntPtr.Zero;
-				ulong bufferSize = 0;
+				nuint bufferSize = 0;
 
 				if (dispatchDataPtr != IntPtr.Zero) {
 					dispatchData = new DispatchData (dispatchDataPtr, owns: false);