Singularity/Library/PackageCache/com.unity.burst@1.8.4/Runtime/FunctionPointer.cs
2024-05-06 11:45:45 -07:00

86 lines
2.9 KiB
C#

using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using Unity.Collections.LowLevel.Unsafe;
namespace Unity.Burst
{
/// <summary>
/// Base interface for a function pointer.
/// </summary>
public interface IFunctionPointer
{
/// <summary>
/// Converts a pointer to a function pointer.
/// </summary>
/// <param name="ptr">The native pointer.</param>
/// <returns>An instance of this interface.</returns>
[Obsolete("This method will be removed in a future version of Burst")]
IFunctionPointer FromIntPtr(IntPtr ptr);
}
/// <summary>
/// A function pointer that can be used from a Burst Job or from regular C#.
/// It needs to be compiled through <see cref="BurstCompiler.CompileFunctionPointer{T}"/>
/// </summary>
/// <typeparam name="T">Type of the delegate of this function pointer</typeparam>
public readonly struct FunctionPointer<T> : IFunctionPointer
{
// DOTSPLAYER's shim package relies on Burst for it's jobs code
// so Burst does not see the DOTSPLAYER definition of this attribute
#if !UNITY_DOTSPLAYER
[NativeDisableUnsafePtrRestriction]
#endif
private readonly IntPtr _ptr;
/// <summary>
/// Creates a new instance of this function pointer with the following native pointer.
/// </summary>
/// <param name="ptr"></param>
public FunctionPointer(IntPtr ptr)
{
_ptr = ptr;
}
/// <summary>
/// Gets the underlying pointer.
/// </summary>
public IntPtr Value => _ptr;
[Conditional("ENABLE_UNITY_COLLECTIONS_CHECKS")]
private void CheckIsCreated()
{
if (!IsCreated)
{
throw new NullReferenceException("Object reference not set to an instance of an object");
}
}
/// <summary>
/// Gets the delegate associated to this function pointer in order to call the function pointer.
/// This delegate can be called from a Burst Job or from regular C#.
/// If calling from regular C#, it is recommended to cache the returned delegate of this property
/// instead of using this property every time you need to call the delegate.
/// </summary>
public T Invoke
{
get
{
CheckIsCreated();
return Marshal.GetDelegateForFunctionPointer<T>(_ptr);
}
}
/// <summary>
/// Whether the function pointer is valid.
/// </summary>
public bool IsCreated => _ptr != IntPtr.Zero;
/// <summary>
/// Converts a pointer to a function pointer.
/// </summary>
/// <param name="ptr">The native pointer.</param>
/// <returns>An instance of this interface.</returns>
IFunctionPointer IFunctionPointer.FromIntPtr(IntPtr ptr) => new FunctionPointer<T>(ptr);
}
}