Fix early disposal of streams and unpinning of memory for Font and Music (#283)

* Fix early disposal of streams and unpinning of memory for Font and Music

Co-authored-by: Lukas Dürrenberger <[email protected]>

Author: Marioalexsan

.github/workflows/ci.yml

@@ -41,6 +41,7 @@ jobs:
         run: dotnet new globaljson --sdk-version ${{ steps.setup-dotnet.outputs.dotnet-version }} --force
       - name: Verify SDK Installation
         run: dotnet --info
+        continue-on-error: true
 
       - name: Install SFML.Net Dependencies
         run: dotnet restore

src/SFML.Audio/Music.cs

@@ -49,6 +49,8 @@ public Music(string filename) :
         public Music(Stream stream) :
             base(IntPtr.Zero)
         {
+            // Stream needs to stay alive as long as the Music instance is alive
+            // Disposing of it can only be done in Music's Dispose method
             myStream = new StreamAdaptor(stream);
             CPointer = sfMusic_createFromStream(myStream.InputStreamPtr);
 
@@ -74,17 +76,14 @@ public Music(Stream stream) :
         public Music(byte[] bytes) :
             base(IntPtr.Zero)
         {
-            GCHandle pin = GCHandle.Alloc(bytes, GCHandleType.Pinned);
-            try
-            {
-                CPointer = sfMusic_createFromMemory(pin.AddrOfPinnedObject(), (UIntPtr)bytes.Length);
-            }
-            finally
-            {
-                pin.Free();
-            }
+            // Memory needs to stay pinned as long as the Music instance is alive
+            // Freeing the handle can only be done in Music's Dispose method
+            myBytesPin = GCHandle.Alloc(bytes, GCHandleType.Pinned);
+            CPointer = sfMusic_createFromMemory(myBytesPin.AddrOfPinnedObject(), (UIntPtr)bytes.Length);
+
             if (IsInvalid)
             {
+                myBytesPin.Free();
                 throw new LoadingFailedException("music");
             }
         }
@@ -370,10 +369,16 @@ protected override void Destroy(bool disposing)
                 }
             }
 
+            if (myBytesPin.IsAllocated)
+            {
+                myBytesPin.Free();
+            }
+
             sfMusic_destroy(CPointer);
         }
 
         private StreamAdaptor myStream = null;
+        private GCHandle myBytesPin;
 
         /// <summary>
         /// Structure defining a Time range. 

src/SFML.Graphics/Font.cs

@@ -41,10 +41,10 @@ public Font(string filename) : base(sfFont_createFromFile(filename))
         ////////////////////////////////////////////////////////////
         public Font(Stream stream) : base(IntPtr.Zero)
         {
-            using (var adaptor = new StreamAdaptor(stream))
-            {
-                CPointer = sfFont_createFromStream(adaptor.InputStreamPtr);
-            }
+            // Stream needs to stay alive as long as the Font instance is alive
+            // Disposing of it can only be done in Font's Dispose method
+            myStream = new StreamAdaptor(stream);
+            CPointer = sfFont_createFromStream(myStream.InputStreamPtr);
 
             if (IsInvalid)
             {
@@ -62,17 +62,14 @@ public Font(Stream stream) : base(IntPtr.Zero)
         public Font(byte[] bytes) :
             base(IntPtr.Zero)
         {
-            GCHandle pin = GCHandle.Alloc(bytes, GCHandleType.Pinned);
-            try
-            {
-                CPointer = sfFont_createFromMemory(pin.AddrOfPinnedObject(), (UIntPtr)bytes.Length);
-            }
-            finally
-            {
-                pin.Free();
-            }
+            // Memory needs to stay pinned as long as the Font instance is alive
+            // Freeing the handle can only be done in Font's Dispose method
+            myBytesPin = GCHandle.Alloc(bytes, GCHandleType.Pinned);
+            CPointer = sfFont_createFromMemory(myBytesPin.AddrOfPinnedObject(), (UIntPtr)bytes.Length);
+
             if (IsInvalid)
             {
+                myBytesPin.Free();
                 throw new LoadingFailedException("font");
             }
         }
@@ -235,6 +232,11 @@ protected override void Destroy(bool disposing)
                 }
             }
 
+            if (myBytesPin.IsAllocated)
+            {
+                myBytesPin.Free();
+            }
+
             if (!disposing)
             {
                 Context.Global.SetActive(false);
@@ -274,6 +276,7 @@ internal struct InfoMarshalData
 
         private Dictionary<uint, Texture> myTextures = new Dictionary<uint, Texture>();
         private SFML.System.StreamAdaptor myStream = null;
+        private GCHandle myBytesPin;
 
         #region Imports
         [DllImport(CSFML.graphics, CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]