[Experimental] .NET bindings + Avalonia example via Diplomat .NET backend

Cargo.toml

@@ -205,7 +205,3 @@ opt-level = 3
 [profile.test.package.rand_chacha]
 opt-level = 3
 
-[patch.crates-io]
-# FIXME: We need to catch up with Diplomat upstream again, but this is a significant amount of work.
-# In the meantime, we use this forked version which fixes an undefined behavior in the code expanded by the bridge macro.
-diplomat = { git = "https://github.com/CBenoit/diplomat", rev = "6dc806e80162b6b39509a04a2835744236cd2396" }

ffi/Cargo.toml

@@ -12,8 +12,8 @@ test = false
 doctest = false
 
 [dependencies]
-diplomat = "0.7"
-diplomat-runtime = "0.7"
+diplomat = { git = "https://github.com/irvingoujAtDevolution/diplomat.git", rev = "822b0b3effd892ca5babae7c1872d8c6be0685de" }
+diplomat-runtime = { git = "https://github.com/irvingoujAtDevolution/diplomat.git", rev = "822b0b3effd892ca5babae7c1872d8c6be0685de" }
 ironrdp = { path = "../crates/ironrdp", features = ["session", "connector", "dvc", "svc", "rdpdr", "rdpsnd", "graphics", "input", "cliprdr", "displaycontrol"] }
 ironrdp-cliprdr-native.path = "../crates/ironrdp-cliprdr-native"
 ironrdp-dvc-pipe-proxy.path = "../crates/ironrdp-dvc-pipe-proxy"

ffi/dotnet-interop-conf.toml

@@ -1,10 +1,9 @@
+lib_name = "DevolutionsIronRdp"
+
+[dotnet]
 namespace = "Devolutions.IronRdp"
 native_lib = "DevolutionsIronRdp"
-
-[exceptions]
-trim_suffix = "Error"
-error_message_method = "ToDisplay"
-
-[properties]
+exception_trim_suffix = "Error"
+exception_message_method = "ToDisplay"
 setters_prefix = "set_"
 getters_prefix = "get_"

ffi/dotnet/Devolutions.IronRdp.AvaloniaExample/Devolutions.IronRdp.AvaloniaExample.csproj

@@ -23,5 +23,9 @@
 
   <ItemGroup Condition="'$([System.OperatingSystem]::IsWindows())'">
     <PackageReference Include="Avalonia.Win32" Version="11.3.7" />
+    <Content Include="../../../dependencies/runtimes/win-x64/native/DevolutionsIronRdp.dll">
+      <Link>DevolutionsIronRdp.dll</Link>
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
   </ItemGroup>
 </Project>

ffi/dotnet/Devolutions.IronRdp/Generated/Action.cs

@@ -1,40 +1,69 @@
 // <auto-generated/> by Diplomat
 
-#pragma warning disable 0105
 using System;
 using System.Runtime.InteropServices;
-
 using Devolutions.IronRdp.Diplomat;
-#pragma warning restore 0105
 
 namespace Devolutions.IronRdp;
 
 #nullable enable
 
 public partial class Action: IDisposable
 {
-    private unsafe Raw.Action* _inner;
+    private unsafe RustHandle<Raw.Action> _inner;
+
+    /// <summary>
+    /// Roots the wrappers this value borrows from so the GC cannot finalize
+    /// a borrowed-from parent while this value is alive.
+    /// </summary>
+    private object[] _edges;
+
+    private static readonly unsafe RustDestructor<Raw.Action> _destroy = Raw.Action.Destroy;
 
     /// <summary>
     /// Creates a managed <c>Action</c> from a raw handle.
     /// </summary>
     /// <remarks>
-    /// Safety: you should not build two managed objects using the same raw handle (may causes use-after-free and double-free).
+    /// Safety: you should not build two managed objects using the same raw handle (may cause use-after-free and double-free).
     /// <br/>
     /// This constructor assumes the raw struct is allocated on Rust side.
     /// If implemented, the custom Drop implementation on Rust side WILL run on destruction.
     /// </remarks>
-    public unsafe Action(Raw.Action* handle)
+    internal unsafe Action(Raw.Action* handle)
+    {
+        _inner = RustHandle<Raw.Action>.Owned(handle, _destroy);
+        _edges = System.Array.Empty<object>();
+    }
+
+    /// <remarks>
+    /// Edges only keep the borrowed-from objects GC-reachable. Explicitly
+    /// <c>Dispose</c>-ing a parent while a borrowing child is in use is still a
+    /// use-after-free and remains the caller's responsibility.
+    /// </remarks>
+    internal unsafe Action(Raw.Action* handle, object[] edges)
+    {
+        _inner = RustHandle<Raw.Action>.Owned(handle, _destroy);
+        _edges = edges;
+    }
+
+    /// <summary>
+    /// Wraps a handle that already knows whether it owns the pointer. A
+    /// borrowed return passes a non-owning handle, so Dispose and the finalizer
+    /// leave Rust's pointer alone; the edges keep the borrowed-from owners alive
+    /// while this view is in use.
+    /// </summary>
+    internal unsafe Action(RustHandle<Raw.Action> inner, object[] edges)
     {
-        _inner = handle;
+        _inner = inner;
+        _edges = edges;
     }
 
     /// <summary>
     /// Returns the underlying raw handle.
     /// </summary>
-    public unsafe Raw.Action* AsFFI()
+    internal unsafe Raw.Action* AsFFI()
     {
-        return _inner;
+        return _inner.Ptr;
     }
 
     /// <summary>
@@ -44,13 +73,14 @@ public void Dispose()
     {
         unsafe
         {
-            if (_inner == null)
+            if (_inner.IsNull)
             {
                 return;
             }
 
-            Raw.Action.Destroy(_inner);
-            _inner = null;
+            _inner.Release();
+            _inner = default;
+            _edges = System.Array.Empty<object>(); // release refs so borrowed-from owners can be GC'd
 
             GC.SuppressFinalize(this);
         }
@@ -60,4 +90,4 @@ public void Dispose()
     {
         Dispose();
     }
-}
+}