Cleanup runtime platform classes

build/CoreLibraries.props

@@ -8,6 +8,5 @@
       <ProjectReference Include="$(MSBuildThisFileDirectory)/../src/Markup/Avalonia.Markup/Avalonia.Markup.csproj" />
       <ProjectReference Include="$(MSBuildThisFileDirectory)/../src/Markup/Avalonia.Markup.Xaml/Avalonia.Markup.Xaml.csproj" />
       <ProjectReference Include="$(MSBuildThisFileDirectory)/../src/Avalonia.MicroCom/Avalonia.MicroCom.csproj" />
-      <ProjectReference Include="$(MSBuildThisFileDirectory)/../src/Avalonia.PlatformSupport/Avalonia.PlatformSupport.csproj" />
   </ItemGroup>
 </Project>

nukebuild/Build.cs

@@ -221,7 +221,6 @@ void RunCoreTest(string projectName)
             RunCoreTest("Avalonia.Markup.Xaml.UnitTests");
             RunCoreTest("Avalonia.Skia.UnitTests");
             RunCoreTest("Avalonia.ReactiveUI.UnitTests");
-            RunCoreTest("Avalonia.PlatformSupport.UnitTests");
         });
 
     Target RunRenderTests => _ => _

src/Avalonia.Base/Avalonia.Base.csproj

@@ -28,7 +28,6 @@
     <InternalsVisibleTo Include="Avalonia.Direct2D1.RenderTests, PublicKey=$(AvaloniaPublicKey)" />
     <InternalsVisibleTo Include="Avalonia.LeakTests, PublicKey=$(AvaloniaPublicKey)" />
     <InternalsVisibleTo Include="Avalonia.Markup.Xaml.UnitTests, PublicKey=$(AvaloniaPublicKey)" />
-    <InternalsVisibleTo Include="Avalonia.PlatformSupport, PublicKey=$(AvaloniaPublicKey)" />
     <InternalsVisibleTo Include="Avalonia.Skia.RenderTests, PublicKey=$(AvaloniaPublicKey)" />
     <InternalsVisibleTo Include="Avalonia.Skia.UnitTests, PublicKey=$(AvaloniaPublicKey)" />
     <InternalsVisibleTo Include="Avalonia.UnitTests, PublicKey=$(AvaloniaPublicKey)" />

src/Avalonia.PlatformSupport/AssetLoader.cs → src/Avalonia.Base/Platform/AssetLoader.cs

@@ -3,11 +3,10 @@
 using System.IO;
 using System.Linq;
 using System.Reflection;
-using Avalonia.Platform;
-using Avalonia.PlatformSupport.Internal;
+using Avalonia.Platform.Internal;
 using Avalonia.Utilities;
 
-namespace Avalonia.PlatformSupport
+namespace Avalonia.Platform
 {
     /// <summary>
     /// Loads assets compiled into the application binary.

src/Avalonia.PlatformSupport/Internal/AssemblyDescriptor.cs → src/Avalonia.Base/Platform/Internal/AssemblyDescriptor.cs

@@ -4,7 +4,7 @@
 using System.Reflection;
 using Avalonia.Utilities;
 
-namespace Avalonia.PlatformSupport.Internal;
+namespace Avalonia.Platform.Internal;
 
 internal interface IAssemblyDescriptor
 {

src/Avalonia.PlatformSupport/Internal/AssemblyDescriptorResolver.cs → src/Avalonia.Base/Platform/Internal/AssemblyDescriptorResolver.cs

@@ -2,8 +2,9 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
+using System.Runtime.CompilerServices;
 
-namespace Avalonia.PlatformSupport.Internal;
+namespace Avalonia.Platform.Internal;
 
 internal interface IAssemblyDescriptorResolver
 {
@@ -29,9 +30,8 @@ public IAssemblyDescriptor GetAssembly(string name)
             }
             else
             {
-                // iOS does not support loading assemblies dynamically!
 #if NET6_0_OR_GREATER
-                if (OperatingSystem.IsIOS())
+                if (!RuntimeFeature.IsDynamicCodeSupported)
                 {
                     throw new InvalidOperationException(
                         $"Assembly {name} needs to be referenced and explicitly loaded before loading resources");

src/Avalonia.PlatformSupport/Internal/AssetDescriptor.cs → src/Avalonia.Base/Platform/Internal/AssetDescriptor.cs

@@ -2,7 +2,7 @@
 using System.IO;
 using System.Reflection;
 
-namespace Avalonia.PlatformSupport.Internal;
+namespace Avalonia.Platform.Internal;
 
 internal interface IAssetDescriptor
 {

src/Avalonia.PlatformSupport/Internal/Constants.cs → src/Avalonia.Base/Platform/Internal/Constants.cs

@@ -1,4 +1,4 @@
-namespace Avalonia.PlatformSupport.Internal;
+namespace Avalonia.Platform.Internal;
 
 internal static class Constants
 {

src/Avalonia.PlatformSupport/DynLoader.cs → src/Avalonia.Base/Platform/Internal/DynLoader.cs

@@ -3,7 +3,7 @@
 using Avalonia.Platform.Interop;
 
 // ReSharper disable InconsistentNaming
-namespace Avalonia.PlatformSupport
+namespace Avalonia.Platform.Internal
 {
     class UnixLoader : IDynamicLibraryLoader
     {
@@ -26,25 +26,6 @@ public static void Init()
             }
         }
 
-        static class AndroidImports
-        {
-            [DllImport("libdl.so")]
-            private static extern IntPtr dlopen(string path, int flags);
-
-            [DllImport("libdl.so")]
-            private static extern IntPtr dlsym(IntPtr handle, string symbol);
-
-            [DllImport("libdl.so")]
-            private static extern IntPtr dlerror();
-
-            public static void Init()
-            {
-                DlOpen = dlopen;
-                DlSym = dlsym;
-                DlError = dlerror;
-            }
-        }
-
         static class OsXImports
         {
             [DllImport("/usr/lib/libSystem.dylib")]
@@ -77,10 +58,6 @@ static UnixLoader()
             Marshal.FreeHGlobal(buffer);
             if (unixName == "Darwin")
                 OsXImports.Init();
-#if NET6_0_OR_GREATER
-            else if (OperatingSystem.IsAndroid())
-                AndroidImports.Init();
-#endif
             else
                 LinuxImports.Init();
         }
@@ -135,6 +112,39 @@ IntPtr IDynamicLibraryLoader.GetProcAddress(IntPtr dll, string proc, bool option
             return ptr;
         }
     }
+
+#if NET6_0_OR_GREATER
+    internal class Net6Loader : IDynamicLibraryLoader
+    {
+        public IntPtr LoadLibrary(string dll)
+        {
+            try
+            {
+                return NativeLibrary.Load(dll);
+            }
+            catch (Exception ex)
+            {
+                throw new DynamicLibraryLoaderException("Error loading " + dll, ex);
+            }
+        }
+
+        public IntPtr GetProcAddress(IntPtr dll, string proc, bool optional)
+        {
+            try
+            {
+                if (optional)
+                {
+                    return NativeLibrary.TryGetExport(dll, proc, out var address) ? address : default;
+                }
+                return NativeLibrary.GetExport(dll, proc);
+            }
+            catch (Exception ex)
+            {
+                throw new DynamicLibraryLoaderException("Error " + dll, ex);
+            }
+        }
+    }
+#endif
 
     internal class NotSupportedLoader : IDynamicLibraryLoader
     {

src/Avalonia.PlatformSupport/Internal/SlicedStream.cs → src/Avalonia.Base/Platform/Internal/SlicedStream.cs

@@ -1,7 +1,7 @@
 using System;
 using System.IO;
 
-namespace Avalonia.PlatformSupport.Internal;
+namespace Avalonia.Platform.Internal;
 
 internal class SlicedStream : Stream
 {

src/Avalonia.Base/Platform/Internal/UnmanagedBlob.cs

@@ -0,0 +1,155 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using System.Threading;
+
+namespace Avalonia.Platform.Internal;
+
+internal class UnmanagedBlob : IUnmanagedBlob
+{
+    private IntPtr _address;
+    private readonly object _lock = new object();
+#if DEBUG
+    private static readonly List<string> Backtraces = new List<string>();
+    private static Thread? GCThread;
+    private readonly string _backtrace;
+    private static readonly object _btlock = new object();
+
+    class GCThreadDetector
+    {
+        ~GCThreadDetector()
+        {
+            GCThread = Thread.CurrentThread;
+        }
+    }
+
+    [MethodImpl(MethodImplOptions.NoInlining)]
+    static void Spawn() => new GCThreadDetector();
+
+    static UnmanagedBlob()
+    {
+        Spawn();
+        GC.WaitForPendingFinalizers();
+    }
+#endif
+
+    public UnmanagedBlob(int size)
+    {
+        try
+        {
+            if (size <= 0)
+                throw new ArgumentException("Positive number required", nameof(size));
+            _address = Alloc(size);
+            GC.AddMemoryPressure(size);
+            Size = size;
+        }
+        catch
+        {
+            GC.SuppressFinalize(this);
+            throw;
+        }
+#if DEBUG
+        _backtrace = Environment.StackTrace;
+        lock (_btlock)
+            Backtraces.Add(_backtrace);
+#endif
+    }
+
+    void DoDispose()
+    {
+        lock (_lock)
+        {
+            if (!IsDisposed)
+            {
+#if DEBUG
+                lock (_btlock)
+                    Backtraces.Remove(_backtrace);
+#endif
+                Free(_address, Size);
+                GC.RemoveMemoryPressure(Size);
+                IsDisposed = true;
+                _address = IntPtr.Zero;
+                Size = 0;
+            }
+        }
+    }
+
+    public void Dispose()
+    {
+#if DEBUG
+        if (Thread.CurrentThread.ManagedThreadId == GCThread?.ManagedThreadId)
+        {
+            lock (_lock)
+            {
+                if (!IsDisposed)
+                {
+                    Console.Error.WriteLine("Native blob disposal from finalizer thread\nBacktrace: "
+                                         + Environment.StackTrace
+                                         + "\n\nBlob created by " + _backtrace);
+                }
+            }
+        }
+#endif
+        DoDispose();
+        GC.SuppressFinalize(this);
+    }
+
+    ~UnmanagedBlob()
+    {
+#if DEBUG
+        Console.Error.WriteLine("Undisposed native blob created by " + _backtrace);
+#endif
+        DoDispose();
+    }
+
+    public IntPtr Address => IsDisposed ? throw new ObjectDisposedException("UnmanagedBlob") : _address;
+    public int Size { get; private set; }
+    public bool IsDisposed { get; private set; }
+
+    [DllImport("libc", SetLastError = true)]
+    private static extern IntPtr mmap(IntPtr addr, IntPtr length, int prot, int flags, int fd, IntPtr offset);
+    [DllImport("libc", SetLastError = true)]
+    private static extern int munmap(IntPtr addr, IntPtr length);
+    [DllImport("libc", SetLastError = true)]
+    private static extern long sysconf(int name);
+
+    private bool? _useMmap;
+    private bool UseMmap
+        => _useMmap ?? ((_useMmap = RuntimeInformation.IsOSPlatform(OSPlatform.Linux)).Value);
+
+    // Could be replaced with https://github.com/dotnet/runtime/issues/40892 when it will be available.
+    private IntPtr Alloc(int size)
+    {
+        if (!UseMmap)
+        {
+            return Marshal.AllocHGlobal(size);
+        }
+        else
+        {
+            var rv = mmap(IntPtr.Zero, new IntPtr(size), 3, 0x22, -1, IntPtr.Zero);
+            if (rv.ToInt64() == -1 || (ulong)rv.ToInt64() == 0xffffffff)
+            {
+                var errno = Marshal.GetLastWin32Error();
+                throw new Exception("Unable to allocate memory: " + errno);
+            }
+            return rv;
+        }
+    }
+
+    private void Free(IntPtr ptr, int len)
+    {
+        if (!UseMmap)
+        {
+            Marshal.FreeHGlobal(ptr);
+        }
+        else
+        {
+            if (munmap(ptr, new IntPtr(len)) == -1)
+            {
+                var errno = Marshal.GetLastWin32Error();
+                throw new Exception("Unable to free memory: " + errno);
+            }
+        }
+    }
+}

src/Avalonia.Base/Platform/Interop/IDynamicLibraryLoader.cs

@@ -16,5 +16,10 @@ public DynamicLibraryLoaderException(string message) : base(message)
         {
 
         }
+
+        public DynamicLibraryLoaderException(string message, Exception innerException) : base(message, innerException)
+        {
+
+        }
     }
 }