Init

FfiChannels/Ffi.cs

@@ -0,0 +1,43 @@
+using System.Runtime.InteropServices;
+
+namespace FfiChannels
+{
+    [StructLayout(LayoutKind.Sequential)]
+    public struct ByteArray
+    {
+        public IntPtr data;
+        public int length;
+
+        public byte[] ToByteArray() {
+            var array = new byte[length];
+            Marshal.Copy(data, array, 0, length);
+            return array;
+        }
+    }
+
+    public delegate void Callback(ByteArray byteArray);
+
+    public static class Bindings {
+
+        [DllImport("ffi_channels")]
+        public static extern void send(byte[] data, int length);
+
+        [DllImport("ffi_channels")]
+        public static extern ByteArray receive();
+
+        [DllImport("ffi_channels")]
+        public static extern void register_callback(Callback cb);
+
+        [DllImport("ffi_channels")]
+        public static extern void start_listening();
+
+        public static Task<byte[]> ReceiveAsync() {
+            return Task.Run(() => {
+                Console.WriteLine("Receiving..");
+                var ptr = receive(); //blocking call
+                Console.WriteLine("Received!");
+                return ptr.ToByteArray();
+            });
+        }
+    }
+}

FfiChannels/FfiChannels.csproj

@@ -0,0 +1,21 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net7.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <PropertyGroup>
+    <NativeOutputPath>../target/debug</NativeOutputPath>
+    <LibraryName>ffi_channels</LibraryName>
+  </PropertyGroup>
+
+  <ItemGroup>
+      <None Condition="$([MSBuild]::IsOsPlatform('MacOS'))" Include="$(NativeOutputPath)/lib$(LibraryName).dylib" CopyToOutputDirectory="PreserveNewest" />
+      <None Condition="$([MSBuild]::IsOsPlatform('Linux'))" Include="$(NativeOutputPath)/lib$(LibraryName).so" CopyToOutputDirectory="PreserveNewest" />
+      <None Condition="$([MSBuild]::IsOsPlatform('Windows'))" Include="$(NativeOutputPath)/$(LibraryName).dll" CopyToOutputDirectory="PreserveNewest" />
+  </ItemGroup>
+
+</Project>

FfiChannels/Program.cs

@@ -0,0 +1,25 @@
+using FfiChannels;
+
+Bindings.register_callback((bytes) => {
+    var data = bytes.ToByteArray();
+    Console.WriteLine($"Callback called, bytes: {string.Join(',',data)}");
+});
+Bindings.start_listening();
+
+Console.WriteLine("Press key to send");
+Console.ReadKey(true);
+
+Bindings.send(new byte[]{ 1,2,3,4,5,6,7,8,9,10 }, 10);
+
+Console.WriteLine("Press key to exit");
+Console.ReadKey(true);
+
+// var receiving = Bindings.ReceiveAsync();
+// Console.WriteLine("Press key to send");
+// Console.ReadKey(true);
+// Console.WriteLine("Hello world, sending data to Rust:");
+// Bindings.send(new byte[]{ 1,2,3,4,5,6,7,8,9,10 }, 10);
+// Console.WriteLine("Press a key to receive");
+// Console.ReadKey(true);
+// var data = await receiving;
+// Console.WriteLine($"Received: {string.Join(',',data)}");