Reworked VlcManager architecture (#490)

to ensure proper loading/unloading of libvlc*.dll Fixes #482
ZeBobo5 · Jan 30, 2019 · fb42e9a · fb42e9a
1 parent 8b10ba0
commit fb42e9a
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Showing 127 changed files with 304 additions and 337 deletions.
diff --git a/src/Samples/Samples.WinForms.MultiplePlayers/Form1.cs b/src/Samples/Samples.WinForms.MultiplePlayers/Form1.cs
@@ -78,23 +78,23 @@ private void button1_Click(object sender, EventArgs e)
         /// <returns></returns>
         private async Task AddPlayerAsync()
         {
-            await Task.Run(() =>
+            await Task.Run(async () =>
             {
-                AutoResetEvent uiUpdated = new AutoResetEvent(false);
                 var player = new VlcControl
                 {
                     VlcLibDirectory = new DirectoryInfo(this.vlcLibraryPath), 
                     Size = new Size(200, 200)
                 };
 
+                var uiUpdatedTask = new TaskCompletionSource<bool>(TaskCreationOptions.RunContinuationsAsynchronously);
                 panel.BeginInvoke( (MethodInvoker) delegate
                 {
                     panel.Controls.Add(player);
                     player.EndInit();
-                    uiUpdated.Set();
+                    uiUpdatedTask.SetResult(true);
                 });
 
-                uiUpdated.WaitOne();
+                await uiUpdatedTask.Task.ConfigureAwait(false);
 
                 lock (listOfControls)
                 {

diff --git a/...otNet.Core.Interops/VlcInteropsManager.cs → ....DotNet.Core.Interops/VlcLibraryLoader.cs b/...otNet.Core.Interops/VlcInteropsManager.cs → ....DotNet.Core.Interops/VlcLibraryLoader.cs
@@ -10,21 +10,38 @@
 
 namespace Vlc.DotNet.Core.Interops
 {
-    public abstract class VlcInteropsManager : IDisposable
+    /// <summary>
+    /// This class loads the required libvlc libraries.
+    /// Only one instance per directory will be created.
+    ///
+    /// Use <see cref="GetOrCreateLoader" /> and <see cref="ReleaseLoader"/> to get a VlcLibraryLoader instance and release it properly.
+    /// Do not call Dispose() by yourself, it will be called as needed by ReleaseLoader.
+    /// </summary>
+    internal class VlcLibraryLoader: IDisposable
     {
+        private static Dictionary<string, VlcLibraryLoader> myLoaderInstances = new Dictionary<string, VlcLibraryLoader>();
+
+        private readonly DirectoryInfo myDynamicLinkLibrariesPath;
+
         /// <summary>
-        /// Caches of the delegates that were resolved from the libvlc.
-        /// These delegates are cast to the correct delegate type when a query is made
+        /// Number of objects that are using this loader
         /// </summary>
-        private readonly Dictionary<string, object> myInteropDelegates = new Dictionary<string, object>();
+        private int myRefCount;
+
         private IntPtr myLibGccDllHandle;
         private IntPtr myLibVlcDllHandle;
         private IntPtr myLibVlcCoreDllHandle;
 
-        protected VlcInteropsManager(DirectoryInfo dynamicLinkLibrariesPath)
+        /// <summary>
+        /// Caches of the delegates that were resolved from the libvlc.
+        /// These delegates are cast to the correct delegate type when a query is made
+        /// </summary>
+        private readonly Dictionary<string, object> myInteropDelegates = new Dictionary<string, object>();
+
+        private VlcLibraryLoader(DirectoryInfo dynamicLinkLibrariesPath)
         {
-            if (!dynamicLinkLibrariesPath.Exists)
-                throw new DirectoryNotFoundException();
+            myDynamicLinkLibrariesPath = dynamicLinkLibrariesPath;
+            myRefCount = 1;
 
             var libGccDllPath = Path.Combine(dynamicLinkLibrariesPath.FullName, "libgcc_s_seh-1.dll");
             if (File.Exists(libGccDllPath))
@@ -65,7 +82,7 @@ internal T GetInteropDelegate<T>()
                 vlcFunctionName = attr.FunctionName;
                 if (myInteropDelegates.ContainsKey(vlcFunctionName))
                 {
-                    return (T) myInteropDelegates[attr.FunctionName];
+                    return (T)myInteropDelegates[attr.FunctionName];
                 }
 
                 var procAddress = Win32Interops.GetProcAddress(myLibVlcDllHandle, attr.FunctionName);
@@ -82,13 +99,7 @@ internal T GetInteropDelegate<T>()
             }
         }
 
-        public void Dispose()
-        {
-            Dispose(true);
-            GC.SuppressFinalize(this);
-        }
-
-        public virtual void Dispose(bool disposing)
+        void IDisposable.Dispose()
         {
             if (myLibVlcDllHandle != IntPtr.Zero)
             {
@@ -107,9 +118,47 @@ public virtual void Dispose(bool disposing)
             }
         }
 
-        ~VlcInteropsManager()
+        /// <summary>
+        /// Creates a new VlcLibraryLoader, or get the existing one for that folder from the dictionary (increment its reference count).
+        /// </summary>
+        /// <param name="dynamicLinkLibrariesPath">The path from the dictionary</param>
+        /// <returns>The loader</returns>
+        public static VlcLibraryLoader GetOrCreateLoader(DirectoryInfo dynamicLinkLibrariesPath)
+        {
+            if (!dynamicLinkLibrariesPath.Exists)
+                throw new DirectoryNotFoundException();
+
+            lock (myLoaderInstances)
+            {
+                if (myLoaderInstances.ContainsKey(dynamicLinkLibrariesPath.FullName))
+                {
+                    var instance = myLoaderInstances[dynamicLinkLibrariesPath.FullName];
+                    instance.myRefCount++;
+                    return instance;
+                }
+
+                var returnedInstance = new VlcLibraryLoader(dynamicLinkLibrariesPath);
+                myLoaderInstances[dynamicLinkLibrariesPath.FullName] = returnedInstance;
+                return returnedInstance;
+            }
+        }
+
+        /// <summary>
+        /// Decrements the reference counter of the specified loader.
+        /// If this reference counter reaches 0, it is destroyed
+        /// </summary>
+        /// <param name="loader"></param>
+        public static void ReleaseLoader(VlcLibraryLoader loader)
         {
-            Dispose(false);
+            lock (myLoaderInstances)
+            {
+                loader.myRefCount--;
+                if (loader.myRefCount == 0)
+                {
+                    ((IDisposable)loader).Dispose();
+                    myLoaderInstances.Remove(loader.myDynamicLinkLibrariesPath.FullName);
+                }
+            }
         }
     }
-}
+}
diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.AddOptionFlagToMedia.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.AddOptionFlagToMedia.cs
@@ -12,7 +12,7 @@ public void AddOptionFlagToMedia(VlcMediaInstance mediaInstance, string option,
 
             using (var handle = Utf8InteropStringConverter.ToUtf8StringHandle(option))
             {
-                GetInteropDelegate<AddOptionFlagToMedia>().Invoke(mediaInstance, handle, flag);
+                myLibraryLoader.GetInteropDelegate<AddOptionFlagToMedia>().Invoke(mediaInstance, handle, flag);
             }
         }
     }

diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.AddOptionToMedia.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.AddOptionToMedia.cs
@@ -14,7 +14,7 @@ public void AddOptionToMedia(VlcMediaInstance mediaInstance, string option)
 
             using (var handle = Utf8InteropStringConverter.ToUtf8StringHandle(option))
             {
-                GetInteropDelegate<AddOptionToMedia>().Invoke(mediaInstance, handle);
+                myLibraryLoader.GetInteropDelegate<AddOptionToMedia>().Invoke(mediaInstance, handle);
             }
         }
 

diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.AttachEvent.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.AttachEvent.cs
@@ -11,7 +11,7 @@ public int AttachEvent(VlcEventManagerInstance eventManagerInstance, EventTypes
                 throw new ArgumentException("Event manager instance is not initialized.");
             if (callback == null)
                 throw new ArgumentException("Callback for event is not initialized.");
-            return GetInteropDelegate<AttachEvent>().Invoke(eventManagerInstance, eventType, callback, IntPtr.Zero);
+            return myLibraryLoader.GetInteropDelegate<AttachEvent>().Invoke(eventManagerInstance, eventType, callback, IntPtr.Zero);
         }
     }
 }
diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.ClearLastErrorMessage.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.ClearLastErrorMessage.cs
@@ -6,7 +6,7 @@ public sealed partial class VlcManager
     {
         public void ClearLastErrorMessage()
         {
-            GetInteropDelegate<ClearLastErrorMessage>().Invoke();
+            myLibraryLoader.GetInteropDelegate<ClearLastErrorMessage>().Invoke();
         }
     }
 }
diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.CloneMedia.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.CloneMedia.cs
@@ -9,7 +9,7 @@ public VlcMediaInstance CloneMedia(VlcMediaInstance mediaInstance)
         {
             if (mediaInstance == IntPtr.Zero)
                 throw new ArgumentException("Media instance is not initialized.");
-            return VlcMediaInstance.New(this, GetInteropDelegate<CloneMedia>().Invoke(mediaInstance));
+            return VlcMediaInstance.New(this, myLibraryLoader.GetInteropDelegate<CloneMedia>().Invoke(mediaInstance));
         }
     }
 }
diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.CouldPlay.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.CouldPlay.cs
@@ -9,7 +9,7 @@ public bool CouldPlay(VlcMediaPlayerInstance mediaPlayerInstance)
         {
             if (mediaPlayerInstance == IntPtr.Zero)
                 throw new ArgumentException("Media player instance is not initialized.");
-            return GetInteropDelegate<CouldPlay>().Invoke(mediaPlayerInstance) == 1;
+            return myLibraryLoader.GetInteropDelegate<CouldPlay>().Invoke(mediaPlayerInstance) == 1;
         }
     }
 }
diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.CreateMediaPlayer.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.CreateMediaPlayer.cs
@@ -7,9 +7,7 @@ public sealed partial class VlcManager
     {
         public VlcMediaPlayerInstance CreateMediaPlayer()
         {
-            EnsureVlcInstance();
-
-            return new VlcMediaPlayerInstance(this, GetInteropDelegate<CreateMediaPlayer>().Invoke(myVlcInstance));
+            return new VlcMediaPlayerInstance(this, myLibraryLoader.GetInteropDelegate<CreateMediaPlayer>().Invoke(myVlcInstance));
         }
     }
 }
diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.CreateMediaPlayerFromMedia.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.CreateMediaPlayerFromMedia.cs
@@ -9,7 +9,7 @@ public VlcMediaPlayerInstance CreateMediaPlayerFromMedia(VlcMediaInstance mediaI
         {
             if (mediaInstance == IntPtr.Zero)
                 throw new ArgumentException("Media instance is not initialized.");
-            return new VlcMediaPlayerInstance(this, GetInteropDelegate<CreateMediaPlayerFromMedia>().Invoke(mediaInstance));
+            return new VlcMediaPlayerInstance(this, myLibraryLoader.GetInteropDelegate<CreateMediaPlayerFromMedia>().Invoke(mediaInstance));
         }
     }
 }
diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.CreateNewInstance.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.CreateNewInstance.cs
diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.CreateNewMediaFromFileDescriptor.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.CreateNewMediaFromFileDescriptor.cs
@@ -6,9 +6,7 @@ public sealed partial class VlcManager
     {
         public VlcMediaInstance CreateNewMediaFromFileDescriptor(int fileDescriptor)
         {
-            EnsureVlcInstance();
-
-            return VlcMediaInstance.New(this, GetInteropDelegate<CreateNewMediaFromFileDescriptor>().Invoke(myVlcInstance, fileDescriptor));
+            return VlcMediaInstance.New(this, myLibraryLoader.GetInteropDelegate<CreateNewMediaFromFileDescriptor>().Invoke(myVlcInstance, fileDescriptor));
         }
     }
 }
diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.CreateNewMediaFromLocation.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.CreateNewMediaFromLocation.cs
@@ -6,11 +6,9 @@ public sealed partial class VlcManager
     {
         public VlcMediaInstance CreateNewMediaFromLocation(string mrl)
         {
-            EnsureVlcInstance();
-
             using (var handle = Utf8InteropStringConverter.ToUtf8StringHandle(mrl))
             {
-                return VlcMediaInstance.New(this, GetInteropDelegate<CreateNewMediaFromLocation>().Invoke(myVlcInstance, handle));
+                return VlcMediaInstance.New(this, myLibraryLoader.GetInteropDelegate<CreateNewMediaFromLocation>().Invoke(myVlcInstance, handle));
             }
         }
     }

diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.CreateNewMediaFromPath.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.CreateNewMediaFromPath.cs
@@ -6,11 +6,9 @@ public sealed partial class VlcManager
     {
         public VlcMediaInstance CreateNewMediaFromPath(string mrl)
         {
-            EnsureVlcInstance();
-
             using (var handle = Utf8InteropStringConverter.ToUtf8StringHandle(mrl))
             {
-                return VlcMediaInstance.New(this, GetInteropDelegate<CreateNewMediaFromPath>().Invoke(myVlcInstance, handle));
+                return VlcMediaInstance.New(this, myLibraryLoader.GetInteropDelegate<CreateNewMediaFromPath>().Invoke(myVlcInstance, handle));
             }
         }
     }

diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.CreateNewMediaFromStream.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.CreateNewMediaFromStream.cs
@@ -40,7 +40,7 @@ public VlcMediaInstance CreateNewMediaFromStream(Stream stream)
             if (opaque == IntPtr.Zero)
                 return null;
 
-            var result = VlcMediaInstance.New(this, GetInteropDelegate<CreateNewMediaFromCallbacks>().Invoke(
+            var result = VlcMediaInstance.New(this, myLibraryLoader.GetInteropDelegate<CreateNewMediaFromCallbacks>().Invoke(
                 myVlcInstance,
                 CallbackOpenMediaDelegate,
                 CallbackReadMediaDelegate,

diff --git a/src/Vlc.DotNet.Core.Interops/VlcManager.DetachEvent.cs b/src/Vlc.DotNet.Core.Interops/VlcManager.DetachEvent.cs
@@ -11,7 +11,7 @@ public void DetachEvent(VlcEventManagerInstance eventManagerInstance, EventTypes
                 throw new ArgumentException("Event manager is not initialized.");
             if (callback == null)
                 return;
-            GetInteropDelegate<DetachEvent>().Invoke(eventManagerInstance, eventType, callback, IntPtr.Zero);
+            myLibraryLoader.GetInteropDelegate<DetachEvent>().Invoke(eventManagerInstance, eventType, callback, IntPtr.Zero);
         }
     }
 }
-Original file line number
+Diff line change
@@ Expand Up @@
                 using (var handle = Utf8InteropStringConverter.ToUtf8StringHandle(option))
                 {
-                    GetInteropDelegate<AddOptionFlagToMedia>().Invoke(mediaInstance, handle, flag);
+                    myLibraryLoader.GetInteropDelegate<AddOptionFlagToMedia>().Invoke(mediaInstance, handle, flag);
                 }
             }
         }
@@ Expand Down @@