From 8ed11c6d48f6b4a4349c12186b5c9e38cd578844 Mon Sep 17 00:00:00 2001
From: Friedrich von Never <friedrich@fornever.me>
Date: Sun, 12 Feb 2023 20:20:13 +0100
Subject: [PATCH] (#354) CPtr, FPtr: add tests

---
 Cesium.Runtime.Tests/PtrTests.cs  | 29 +++++++++++++++++++++++++++++
 Cesium.Runtime/CPtr.cs            |  4 ++--
 Cesium.Runtime/FPtr.cs            | 14 ++++++++++++++
 Cesium.Runtime/StringFunctions.cs |  2 +-
 4 files changed, 46 insertions(+), 3 deletions(-)
 create mode 100644 Cesium.Runtime.Tests/PtrTests.cs
 create mode 100644 Cesium.Runtime/FPtr.cs

diff --git a/Cesium.Runtime.Tests/PtrTests.cs b/Cesium.Runtime.Tests/PtrTests.cs
new file mode 100644
index 00000000..ba8120f7
--- /dev/null
+++ b/Cesium.Runtime.Tests/PtrTests.cs
@@ -0,0 +1,29 @@
+namespace Cesium.Runtime.Tests;
+
+public unsafe class PtrTests
+{
+    [Fact]
+    public void CPtrTests()
+    {
+        CPtr v = (void*)0x1234;
+        Assert.Equal(0x1234L, (long)v.AsPtr());
+        Assert.Equal(0x1234L, (long)v.AsPtr<byte>());
+
+        Assert.Equal(sizeof(long), sizeof(CPtr));
+
+        CPtr<int> t = (int*)0x2345;
+        Assert.Equal(0x2345L, (long)t.AsPtr());
+        Assert.Equal((IntPtr)0x2345, t.AsIntPtr());
+        Assert.Equal(0x2345L, (long)t.AsPtr<byte>());
+
+        Assert.Equal(sizeof(long), sizeof(CPtr<int>));
+    }
+
+    [Fact]
+    public void FPtrTests()
+    {
+        var a = new FPtr<Action>((void*)0x1234);
+        Assert.Equal(0x1234L, (long)a.AsPtr());
+        Assert.Equal(sizeof(long), sizeof(FPtr<Action>));
+    }
+}
diff --git a/Cesium.Runtime/CPtr.cs b/Cesium.Runtime/CPtr.cs
index d974bacc..0fb097d5 100644
--- a/Cesium.Runtime/CPtr.cs
+++ b/Cesium.Runtime/CPtr.cs
@@ -1,7 +1,7 @@
 namespace Cesium.Runtime;
 
 /// <summary>A class encapsulating an opaque pointer (aka <code>void*</code> in C).</summary>
-public unsafe readonly struct CPtr
+public readonly unsafe struct CPtr
 {
     private readonly long _value;
 
@@ -19,7 +19,7 @@ private CPtr(long value)
 
 /// <summary>A class encapsulating an object pointer.</summary>
 /// <typeparam name="T">Type this pointer may be resolved to.</typeparam>
-public unsafe readonly struct CPtr<T> where T : unmanaged
+public readonly unsafe struct CPtr<T> where T : unmanaged
 {
     private readonly long _value;
 
diff --git a/Cesium.Runtime/FPtr.cs b/Cesium.Runtime/FPtr.cs
new file mode 100644
index 00000000..0b609c53
--- /dev/null
+++ b/Cesium.Runtime/FPtr.cs
@@ -0,0 +1,14 @@
+namespace Cesium.Runtime;
+
+/// <summary>A class encapsulating a C function pointer.</summary>
+public readonly unsafe struct FPtr<TDelegate> where TDelegate : Delegate // TODO: Think about vararg and empty parameter list encoding.
+{
+    private readonly long _value;
+
+    public FPtr(void* ptr)
+    {
+        _value = (long)ptr;
+    }
+
+    public void* AsPtr() => (void*)_value;
+}
diff --git a/Cesium.Runtime/StringFunctions.cs b/Cesium.Runtime/StringFunctions.cs
index 1ece4c3d..cce1e32d 100644
--- a/Cesium.Runtime/StringFunctions.cs
+++ b/Cesium.Runtime/StringFunctions.cs
@@ -10,7 +10,7 @@ namespace Cesium.Runtime;
 /// <summary>
 /// Functions declared in the string.h
 /// </summary>
-public unsafe static class StringFunctions
+public static unsafe class StringFunctions
 {
     public static uint StrLen(CPtr<byte> str)
     {