Merge pull request #8 from ilyfairy/preview

Preview

UnsafeHelper.IL/IL.il

@@ -30,4 +30,11 @@
     ldarg.0
     ret
   }
+
+  .method public hidebysig static !!T As<class T>(void* objectAddress) cil managed aggressiveinlining
+  {
+    .maxstack 2
+    ldarg.0
+    ret
+  }
 }

UnsafeHelper/ManagedObject.cs

@@ -0,0 +1,44 @@
+using IlyfairyLib.Unsafe.Internal;
+using System;
+using System.Runtime.InteropServices;
+
+namespace IlyfairyLib.Unsafe;
+
+/// <summary>
+/// 自动回收的托管对象
+/// </summary>
+/// <typeparam name="T"></typeparam>
+public unsafe class ManagedObject<T> where T : class
+{
+    /// <summary>
+    /// 前(nint)字节为TypeHandle
+    /// </summary>
+    private readonly byte[] data;
+    public int Size => data.Length;
+    public nint* Handle => (nint*)(UnsafeHelper.GetObjectRawDataAddress(data) + 8);
+    public T Object { get; private set; }
+    private readonly GCHandle gcHandle;
+    private ManagedObject(byte[] data, object obj)
+    {
+        Object = System.Runtime.CompilerServices.Unsafe.As<T>(obj);
+        this.data = data;
+    }
+    public ManagedObject(int size)
+    {
+        if (size <= 8) size = 8;
+        size += 8;
+        data = new byte[size];
+        var handle = Handle;
+        *handle = typeof(T).TypeHandle.Value;
+        Object = IL.As<T>(handle);
+        gcHandle = GCHandle.Alloc(Object);
+    }
+    ~ManagedObject()
+    {
+        gcHandle.Free();
+    }
+    public Span<T> GetDataSpan<T>() where T : unmanaged => new((byte*)Handle + sizeof(nint), Size / sizeof(T));
+    public void ChangeType(Type type) => *Handle = type.TypeHandle.Value;
+    public void ChangeType<T>() => *Handle = typeof(T).TypeHandle.Value;
+    public ManagedObject<TTo> As<TTo>() where TTo : class => System.Runtime.CompilerServices.Unsafe.As<ManagedObject<TTo>>(this);
+}

UnsafeHelper/StructExtension.cs

@@ -0,0 +1,34 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace IlyfairyLib.Unsafe;
+
+public static class StructExtension
+{
+    public static unsafe TStruct ToStruct<TStruct>(this byte[] bytes) where TStruct : struct
+    {
+        if (sizeof(TStruct) != bytes.Length)
+            throw new ArgumentOutOfRangeException(nameof(bytes), "Bytes array should be the same length as struct size.");
+        TStruct val;
+        fixed (byte* p = bytes)
+        {
+            Buffer.MemoryCopy(p, &val, (ulong)sizeof(TStruct), (ulong)sizeof(TStruct));
+            return val;
+        }
+    }
+
+    public static unsafe TStruct ToStruct<TStruct>(this Span<byte> bytes) where TStruct : struct
+    {
+        if (sizeof(TStruct) != bytes.Length)
+            throw new ArgumentOutOfRangeException(nameof(bytes), "Bytes array should be the same length as struct size.");
+        TStruct val;
+        fixed (byte* p = bytes)
+        {
+            Buffer.MemoryCopy(p, &val, (ulong)sizeof(TStruct), (ulong)sizeof(TStruct));
+            return val;
+        }
+    }
+}