[EGL] Egl.GetProcAddress only returns extensions

We have to load statically exported entry points using the regular OS
symbol loading facilities, and only use eglGetProcAddress for
extensions.

Fixes crash in https://github.com/mono/MonoGame/pull/2377

Source/OpenTK/OpenTK.csproj

@@ -163,9 +163,12 @@
     <Compile Include="Math\Matrix4x3.cs" />
     <Compile Include="Math\Matrix4x3d.cs" />
     <Compile Include="Platform\DisplayDeviceBase.cs" />
+    <Compile Include="Platform\Egl\EglUnixContext.cs" />
+    <Compile Include="Platform\Egl\EglWinContext.cs" />
     <Compile Include="Platform\MappedGamePadDriver.cs" />
     <Compile Include="Platform\Windows\WinInputBase.cs" />
     <Compile Include="Platform\Windows\XInputJoystick.cs" />
+    <Compile Include="Platform\X11\Bindings\DL.cs" />
     <Compile Include="Platform\X11\Bindings\INotify.cs" />
     <Compile Include="Platform\X11\Bindings\XI.cs" />
     <Compile Include="ToolkitOptions.cs" />
@@ -828,7 +831,5 @@
       </Properties>
     </MonoDevelop>
   </ProjectExtensions>
-  <ItemGroup>
+  <ItemGroup />
-    <Folder Include="Platform\MacOS\Quartz\" />
-  </ItemGroup>
 </Project>

Source/OpenTK/Platform/Egl/EglContext.cs

@@ -31,10 +31,12 @@ using OpenTK.Graphics;
 
 namespace OpenTK.Platform.Egl
 {
-    class EglContext : EmbeddedGraphicsContext
+    abstract class EglContext : EmbeddedGraphicsContext
     {
         #region Fields
 
+        readonly RenderableFlags Renderable;
+
         EglWindowInfo WindowInfo;
         IntPtr HandleAsEGLContext { get { return Handle.Handle; } set { Handle = new ContextHandle(value); } }
         int swap_interval = 1; // Default interval is defined as 1 in EGL.
@@ -62,10 +64,11 @@ namespace OpenTK.Platform.Egl
             // Select an EGLConfig that matches the desired mode. We cannot use the 'mode'
             // parameter directly, since it may have originated on a different system (e.g. GLX)
             // and it may not support the desired renderer.
+            Renderable = major > 1 ? RenderableFlags.ES2 : RenderableFlags.ES;
             Mode = new EglGraphicsMode().SelectGraphicsMode(mode.ColorFormat,
                 mode.Depth, mode.Stencil, mode.Samples, mode.AccumulatorFormat,
                 mode.Buffers, mode.Stereo,
-                major > 1 ? RenderableFlags.ES2 : RenderableFlags.ES);
+                Renderable);
             if (!Mode.Index.HasValue)
                 throw new GraphicsModeException("Invalid or unsupported GraphicsMode.");
             IntPtr config = Mode.Index.Value;
@@ -144,11 +147,27 @@ namespace OpenTK.Platform.Egl
 
         public override IntPtr GetAddress(IntPtr function)
         {
-            return Egl.GetProcAddress(function);
+            // Try loading a static export from ES1 or ES2
+            IntPtr address = GetStaticAddress(function, Renderable);
+
+            // If a static export is not available, try retrieving an extension
+            // function pointer with eglGetProcAddress
+            if (address == IntPtr.Zero)
+            {
+                address = Egl.GetProcAddress(function);
+            }
+
+            return address;
         }
 
         #endregion
 
+        #region Abstract Members
+
+        protected abstract IntPtr GetStaticAddress(IntPtr function, RenderableFlags renderable);
+
+        #endregion
+
         #region IDisposable Members
 
         public override void Dispose()
@@ -159,7 +178,7 @@ namespace OpenTK.Platform.Egl
 
         // Todo: cross-reference the specs. What should happen if the context is destroyed from a different
         // thread?
-        void Dispose(bool manual)
+        protected virtual void Dispose(bool manual)
         {
             if (!IsDisposed)
             {

Source/OpenTK/Platform/Egl/EglUnixContext.cs

@@ -0,0 +1,79 @@
+#region License
+//
+// EglUnixContext.cs
+//
+// Author:
+//       Stefanos A. <stapostol@gmail.com>
+//
+// Copyright (c) 2006-2014 Stefanos Apostolopoulos
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+#endregion
+
+using System;
+using OpenTK.Graphics;
+
+namespace OpenTK.Platform.Egl
+{
+    class EglUnixContext : EglContext
+    {
+        readonly IntPtr ES1 = OpenTK.Platform.X11.DL.Open("libGLESv1_CM", X11.DLOpenFlags.Lazy);
+        readonly IntPtr ES2 = OpenTK.Platform.X11.DL.Open("libGLESv2", X11.DLOpenFlags.Lazy);
+
+        public EglUnixContext(GraphicsMode mode, EglWindowInfo window, IGraphicsContext sharedContext,
+            int major, int minor, GraphicsContextFlags flags)
+            : base(mode, window, sharedContext, major, minor, flags)
+        {
+        }
+
+        public EglUnixContext(ContextHandle handle, EglWindowInfo window, IGraphicsContext sharedContext,
+            int major, int minor, GraphicsContextFlags flags)
+            : base(handle, window, sharedContext, major, minor, flags)
+        {
+        }
+
+        protected override IntPtr GetStaticAddress(IntPtr function, RenderableFlags renderable)
+        {
+            if ((renderable & RenderableFlags.ES) != 0 && ES1 != IntPtr.Zero)
+            {
+                return X11.DL.Symbol(ES1, function);
+            }
+            else if ((renderable & RenderableFlags.ES2) != 0 && ES2 != IntPtr.Zero)
+            {
+                return X11.DL.Symbol(ES2, function);
+            }
+            return IntPtr.Zero;
+        }
+
+        protected override void Dispose(bool manual)
+        {
+            if (ES1 != IntPtr.Zero)
+            {
+                X11.DL.Close(ES1);
+            }
+            if (ES2 != IntPtr.Zero)
+            {
+                X11.DL.Close(ES2);
+            }
+
+            base.Dispose(manual);
+        }
+    }
+}

Source/OpenTK/Platform/Egl/EglWinContext.cs

@@ -0,0 +1,83 @@
+#region License
+//
+// EglWinContext.cs
+//
+// Author:
+//       Stefanos A. <stapostol@gmail.com>
+//
+// Copyright (c) 2006-2014 Stefanos Apostolopoulos
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+#endregion
+
+using System;
+using OpenTK.Graphics;
+
+namespace OpenTK.Platform.Egl
+{
+    class EglWinContext : EglContext
+    {
+        readonly IntPtr ES1 = OpenTK.Platform.Windows.Functions.LoadLibrary("libGLESv1_CM");
+        readonly IntPtr ES2 = OpenTK.Platform.Windows.Functions.LoadLibrary("libGLESv2");
+
+        public EglWinContext(GraphicsMode mode, EglWindowInfo window, IGraphicsContext sharedContext,
+            int major, int minor, GraphicsContextFlags flags)
+            : base(mode, window, sharedContext, major, minor, flags)
+        {
+        }
+
+        public EglWinContext(ContextHandle handle, EglWindowInfo window, IGraphicsContext sharedContext,
+            int major, int minor, GraphicsContextFlags flags)
+            : base(handle, window, sharedContext, major, minor, flags)
+        {
+        }
+
+        #region Protected Members
+
+        protected override IntPtr GetStaticAddress(IntPtr function, RenderableFlags renderable)
+        {
+            if ((renderable & RenderableFlags.ES) != 0 && ES1 != IntPtr.Zero)
+            {
+                return Windows.Functions.GetProcAddress(ES1, function);
+            }
+            else if ((renderable & RenderableFlags.ES2) != 0 && ES2 != IntPtr.Zero)
+            {
+                return Windows.Functions.GetProcAddress(ES2, function);
+            }
+            return IntPtr.Zero;
+        }
+
+        protected override void Dispose(bool manual)
+        {
+            if (ES1 != IntPtr.Zero)
+            {
+                Windows.Functions.FreeLibrary(ES1);
+            }
+            if (ES2 != IntPtr.Zero)
+            {
+                Windows.Functions.FreeLibrary(ES2);
+            }
+
+            base.Dispose(manual);
+        }
+
+        #endregion
+    }
+}

Source/OpenTK/Platform/Egl/EglWinPlatformFactory.cs

@@ -44,7 +44,7 @@ namespace OpenTK.Platform.Egl
             WinWindowInfo win_win = (WinWindowInfo)window;
             IntPtr egl_display = GetDisplay(win_win.DeviceContext);
             EglWindowInfo egl_win = new OpenTK.Platform.Egl.EglWindowInfo(win_win.Handle, egl_display);
-            return new EglContext(mode, egl_win, shareContext, major, minor, flags);
+            return new EglWinContext(mode, egl_win, shareContext, major, minor, flags);
         }
 
         public override IGraphicsContext CreateGLContext(ContextHandle handle, IWindowInfo window, IGraphicsContext shareContext, bool directRendering, int major, int minor, GraphicsContextFlags flags)
@@ -52,7 +52,7 @@ namespace OpenTK.Platform.Egl
             WinWindowInfo win_win = (WinWindowInfo)window;
             IntPtr egl_display = GetDisplay(win_win.DeviceContext);
             EglWindowInfo egl_win = new OpenTK.Platform.Egl.EglWindowInfo(win_win.Handle, egl_display);
-            return new EglContext(handle, egl_win, shareContext, major, minor, flags);
+            return new EglWinContext(handle, egl_win, shareContext, major, minor, flags);
         }
 
         public override GraphicsContext.GetCurrentContextDelegate CreateGetCurrentGraphicsContext()

Source/OpenTK/Platform/Egl/EglX11PlatformFactory.cs

@@ -39,14 +39,14 @@ namespace OpenTK.Platform.Egl
         {
             X11WindowInfo x11_win = (X11WindowInfo)window;
             EglWindowInfo egl_win = new OpenTK.Platform.Egl.EglWindowInfo(x11_win.Handle, Egl.GetDisplay(x11_win.Display));
-            return new EglContext(mode, egl_win, shareContext, major, minor, flags);
+            return new EglUnixContext(mode, egl_win, shareContext, major, minor, flags);
         }
 
         public override IGraphicsContext CreateGLContext(ContextHandle handle, IWindowInfo window, IGraphicsContext shareContext, bool directRendering, int major, int minor, GraphicsContextFlags flags)
         {
             X11WindowInfo x11_win = (X11WindowInfo)window;
             EglWindowInfo egl_win = new OpenTK.Platform.Egl.EglWindowInfo(x11_win.Handle, Egl.GetDisplay(x11_win.Display));
-            return new EglContext(handle, egl_win, shareContext, major, minor, flags);
+            return new EglUnixContext(handle, egl_win, shareContext, major, minor, flags);
         }
 
         public override GraphicsContext.GetCurrentContextDelegate CreateGetCurrentGraphicsContext()

Source/OpenTK/Platform/X11/Bindings/DL.cs

@@ -0,0 +1,58 @@
+#region License
+//
+// DL.cs
+//
+// Author:
+//       Stefanos A. <stapostol@gmail.com>
+//
+// Copyright (c) 2006-2014 Stefanos Apostolopoulos
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using System.Text;
+
+namespace OpenTK.Platform.X11
+{
+    class DL
+    {
+        const string lib = "dl";
+
+        [DllImport(lib, EntryPoint = "dlopen")]
+        internal static extern IntPtr Open(string filename, DLOpenFlags flags);
+
+        [DllImport(lib, EntryPoint = "dlclose")]
+        internal static extern int Close(IntPtr handle);
+
+        [DllImport(lib, EntryPoint = "dlsym")]
+        internal static extern IntPtr Symbol(IntPtr handle, IntPtr name);
+    }
+
+    enum DLOpenFlags
+    {
+        Lazy = 0x0001,
+        Now = 0x0002,
+        Global = 0x0100,
+        Local = 0x0000,
+    }
+}