Call XSync in the GLX EGL impl if we have a new X server connection

src/libANGLE/renderer/gl/glx/DisplayGLX.cpp

@@ -49,6 +49,7 @@ DisplayGLX::DisplayGLX()
       mFunctionsGL(nullptr),
       mContext(nullptr),
       mDummyPbuffer(0),
+      mUsesNewXDisplay(false),
       mEGLDisplay(nullptr)
 {
 }
@@ -67,6 +68,7 @@ egl::Error DisplayGLX::initialize(egl::Display *display)
     // the display specified by the DISPLAY environment variable.
     if (xDisplay == EGL_DEFAULT_DISPLAY)
     {
+        mUsesNewXDisplay = true;
         xDisplay = XOpenDisplay(NULL);
         if (!xDisplay)
         {
@@ -155,6 +157,8 @@ egl::Error DisplayGLX::initialize(egl::Display *display)
     mFunctionsGL = new FunctionsGLGLX(mGLX.getProc);
     mFunctionsGL->initialize();
 
+    syncXCommands();
+
     return DisplayGL::initialize(display);
 }
 
@@ -186,7 +190,7 @@ SurfaceImpl *DisplayGLX::createWindowSurface(const egl::Config *configuration,
     ASSERT(configIdToGLXConfig.count(configuration->configID) > 0);
     GLXFBConfig fbConfig = configIdToGLXConfig[configuration->configID];
 
-    return new WindowSurfaceGLX(mGLX, window, mGLX.getDisplay(), mContext, fbConfig);
+    return new WindowSurfaceGLX(mGLX, *this, window, mGLX.getDisplay(), mContext, fbConfig);
 }
 
 SurfaceImpl *DisplayGLX::createPbufferSurface(const egl::Config *configuration,
@@ -379,6 +383,14 @@ std::string DisplayGLX::getVendorString() const
     return "";
 }
 
+void DisplayGLX::syncXCommands() const
+{
+    if (mUsesNewXDisplay)
+    {
+        XSync(mGLX.getDisplay(), False);
+    }
+}
+
 const FunctionsGL *DisplayGLX::getFunctionsGL() const
 {
     return mFunctionsGL;

src/libANGLE/renderer/gl/glx/DisplayGLX.h

@@ -53,6 +53,12 @@ class DisplayGLX : public DisplayGL
 
     std::string getVendorString() const override;
 
+    // Synchronizes with the X server, if the display has been opened by ANGLE.
+    // Calling this is required at the end of every functions that does buffered
+    // X calls (not for glX calls) otherwise there might be race conditions
+    // between the application's display and ANGLE's one.
+    void syncXCommands() const;
+
   private:
     const FunctionsGL *getFunctionsGL() const override;
 
@@ -72,6 +78,8 @@ class DisplayGLX : public DisplayGL
     // A pbuffer the context is current on during ANGLE initialization
     GLXPbuffer mDummyPbuffer;
 
+    bool mUsesNewXDisplay;
+
     FunctionsGLX mGLX;
     egl::Display *mEGLDisplay;
 };

src/libANGLE/renderer/gl/glx/FunctionsGLX.h

@@ -30,7 +30,6 @@ class FunctionsGLX : angle::NonCopyable
     void terminate();
 
     bool hasExtension(const char *extension) const;
-
     int majorVersion;
     int minorVersion;
 

src/libANGLE/renderer/gl/glx/WindowSurfaceGLX.cpp

@@ -10,19 +10,22 @@
 
 #include "common/debug.h"
 
+#include "libANGLE/renderer/gl/glx/DisplayGLX.h"
 #include "libANGLE/renderer/gl/glx/FunctionsGLX.h"
 
 namespace rx
 {
 
-WindowSurfaceGLX::WindowSurfaceGLX(const FunctionsGLX &glx, EGLNativeWindowType window, Display *display, GLXContext context, GLXFBConfig fbConfig)
+WindowSurfaceGLX::WindowSurfaceGLX(const FunctionsGLX &glx, const DisplayGLX &glxDisplay, Window window, Display *display,
+                                   GLXContext context, GLXFBConfig fbConfig)
     : SurfaceGL(),
-      mGLX(glx),
       mParent(window),
+      mWindow(0),
       mDisplay(display),
+      mGLX(glx),
+      mGLXDisplay(glxDisplay),
       mContext(context),
       mFBConfig(fbConfig),
-      mWindow(0),
       mGLXWindow(0)
 {
 }
@@ -38,6 +41,8 @@ WindowSurfaceGLX::~WindowSurfaceGLX()
     {
         XDestroyWindow(mDisplay, mWindow);
     }
+
+    mGLXDisplay.syncXCommands();
 }
 
 egl::Error WindowSurfaceGLX::initialize()
@@ -84,6 +89,8 @@ egl::Error WindowSurfaceGLX::initialize()
     XFree(visualInfo);
     XFreeColormap(mDisplay, colormap);
 
+    mGLXDisplay.syncXCommands();
+
     return egl::Error(EGL_SUCCESS);
 }
 

src/libANGLE/renderer/gl/glx/WindowSurfaceGLX.h

@@ -15,12 +15,14 @@
 namespace rx
 {
 
+class DisplayGLX;
 class FunctionsGLX;
 
 class WindowSurfaceGLX : public SurfaceGL
 {
   public:
-    WindowSurfaceGLX(const FunctionsGLX &glx, Window window, Display *display, GLXContext context, GLXFBConfig fbConfig);
+    WindowSurfaceGLX(const FunctionsGLX &glx, const DisplayGLX &glxDisplay, Window window, Display *display,
+                     GLXContext context, GLXFBConfig fbConfig);
     ~WindowSurfaceGLX() override;
 
     egl::Error initialize();
@@ -38,12 +40,15 @@ class WindowSurfaceGLX : public SurfaceGL
 
     EGLint isPostSubBufferSupported() const override;
   private:
-    const FunctionsGLX &mGLX;
     Window mParent;
+    Window mWindow;
     Display *mDisplay;
+
+    const FunctionsGLX &mGLX;
+    const DisplayGLX &mGLXDisplay;
+
     GLXContext mContext;
     GLXFBConfig mFBConfig;
-    Window mWindow;
     GLXWindow mGLXWindow;
 };