Gen2GcCallback.cs

Go to the documentation of this file.

using System.Runtime.ConstrainedExecution;
using System.Runtime.InteropServices;
 
namespace System;
 
internal sealed class Gen2GcCallback : CriticalFinalizerObject
{
    private readonly Func<bool> _callback0;
 
    private readonly Func<object, bool> _callback1;
 
    private GCHandle _weakTargetObj;
 
    private Gen2GcCallback(Func<bool> callback)
    {
        _callback0 = callback;
    }
 
    private Gen2GcCallback(Func<object, bool> callback, object targetObj)
    {
        _callback1 = callback;
        _weakTargetObj = GCHandle.Alloc(targetObj, GCHandleType.Weak);
    }
 
    public static void Register(Func<bool> callback)
    {
        new Gen2GcCallback(callback);
    }
 
    public static void Register(Func<object, bool> callback, object targetObj)
    {
        new Gen2GcCallback(callback, targetObj);
    }
 
    ~Gen2GcCallback()
    {
        if (_weakTargetObj.IsAllocated)
        {
            object target = _weakTargetObj.Target;
            if (target == null)
            {
                _weakTargetObj.Free();
                return;
            }
            try
            {
                if (!_callback1(target))
                {
                    _weakTargetObj.Free();
                    return;
                }
            }
            catch
            {
            }
        }
        else
        {
            try
            {
                if (!_callback0())
                {
                    return;
                }
            }
            catch
            {
            }
        }
        GC.ReRegisterForFinalize(this);
    }
}