Check if OpenGL context is supported

Before the support for dynamic GL builds, the WebCore initialize OpenGL
shims would check if the OpenGL version had all the necessary methods.
After we removed this we now risk continuing with an OpenGL version that
is not supported by WebCore and can cause crashes.

Task-number: QTBUG-43831
Change-Id: I19caffc645ea5dede8b98408cbe0cae5fae8c22f
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>

1 files changed, 9 insertions, 6 deletions

diff --git a/Source/WebCore/platform/graphics/qt/GraphicsContext3DQt.cpp b/Source/WebCore/platform/graphics/qt/GraphicsContext3DQt.cpp
index edb7636d4..0c9fddc83 100644
--- a/Source/WebCore/platform/graphics/qt/GraphicsContext3DQt.cpp
+++ b/Source/WebCore/platform/graphics/qt/GraphicsContext3DQt.cpp
@@ -100,6 +100,7 @@ public:
     void createGraphicsSurfaces(const IntSize&);
 
     bool isOpenGLES() const;
+    bool isValid() const;
 
     GraphicsContext3D* m_context;
     HostWindow* m_hostWindow;
@@ -123,6 +124,13 @@ bool GraphicsContext3DPrivate::isOpenGLES() const
 #endif
 }
 
+bool GraphicsContext3DPrivate::isValid() const
+{
+    if (!m_platformContext || !m_platformContext->isValid())
+        return false;
+    return m_platformContext->isOpenGLES() || m_platformContext->format().majorVersion() >= 2;
+}
+
 bool GraphicsContext3D::isGLES2Compliant() const
 {
     if (m_private)
@@ -408,12 +416,7 @@ GraphicsContext3D::GraphicsContext3D(GraphicsContext3D::Attributes attrs, HostWi
     m_functions = m_private.get();
     validateAttributes();
 
-    static bool initialized = false;
-    static bool success = true;
-    if (!initialized) {
-        initialized = true;
-    }
-    if (!success) {
+    if (!m_private->isValid()) {
         m_private = nullptr;
         return;
     }