Implement GLX for Ozone X11.

ui/gl/gl_implementation_ozone.cc

Index: ui/gl/gl_implementation_ozone.cc
diff --git a/ui/gl/gl_implementation_ozone.cc b/ui/gl/gl_implementation_ozone.cc
index 715084f50dbf552aea987354bb6b63e3aadc018d..61c52f400ec4c74a4d54191b825f05eec965813b 100644
--- a/ui/gl/gl_implementation_ozone.cc
+++ b/ui/gl/gl_implementation_ozone.cc
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_context_stub_with_extensions.h"
 #include "ui/gl/gl_egl_api_implementation.h"
@@ -13,6 +14,10 @@
 #include "ui/ozone/public/ozone_platform.h"
 #include "ui/ozone/public/surface_factory_ozone.h"
 
+#if defined(USE_GLX)
+#include "ui/gl/gl_glx_api_implementation.h"
+#endif
+
 namespace gfx {
 
 namespace {
@@ -26,9 +31,25 @@ void GL_BINDING_CALL MarshalDepthRangeToDepthRangef(GLclampd z_near,
   glDepthRangef(static_cast<GLclampf>(z_near), static_cast<GLclampf>(z_far));
 }
 
+#if defined(USE_GLX)
+#if defined(OS_OPENBSD)
+const char kGLLibraryName[] = "libGL.so";
+#else
+const char kGLLibraryName[] = "libGL.so.1";
+#endif
+#endif
+
 }  // namespace
 
 void GetAllowedGLImplementations(std::vector<GLImplementation>* impls) {
+#if defined(USE_GLX)
+  // TODO: Discuss/change this before submitting CL.
+  ui::OzonePlatform::InitializeForGPU();
+  // DesktopGL implies GLX on Linux. We only support GLX running the Ozone X11
+  // platform, which requires a runtime check.
+  if (ui::OzonePlatform::GetInstance()->GetSurfaceFactoryOzone()->SupportsGLX())
+    impls->push_back(kGLImplementationDesktopGL);
+#endif
   impls->push_back(kGLImplementationEGLGLES2);
   impls->push_back(kGLImplementationOSMesaGL);
 }
@@ -43,6 +64,41 @@ bool InitializeStaticGLBindings(GLImplementation implementation) {
   switch (implementation) {
     case kGLImplementationOSMesaGL:
       return InitializeStaticGLBindingsOSMesaGL();
+#if defined(USE_GLX)
+    case kGLImplementationDesktopGL: {
+      const base::CommandLine* command_line =
+          base::CommandLine::ForCurrentProcess();
+
+      base::NativeLibrary library = nullptr;
+      if (command_line->HasSwitch(switches::kTestGLLib)) {
+        library = LoadLibraryAndPrintError(
+            command_line->GetSwitchValueASCII(switches::kTestGLLib).c_str());
+      } else {
+        library = LoadLibraryAndPrintError(kGLLibraryName);
+      }
+
+      if (!library)
+        return false;
+
+      GLGetProcAddressProc get_proc_address =
+          reinterpret_cast<GLGetProcAddressProc>(
+              base::GetFunctionPointerFromNativeLibrary(library,
+                                                        "glXGetProcAddress"));
+      if (!get_proc_address) {
+        LOG(ERROR) << "glxGetProcAddress not found.";
+        base::UnloadNativeLibrary(library);
+        return false;
+      }
+
+      SetGLGetProcAddressProc(get_proc_address);
+      AddGLNativeLibrary(library);
+      SetGLImplementation(kGLImplementationDesktopGL);
+
+      InitializeStaticGLBindingsGL();
+      InitializeStaticGLBindingsGLX();
+      break;
+    }
+#endif
     case kGLImplementationEGLGLES2:
       if (!ui::OzonePlatform::GetInstance()
                ->GetSurfaceFactoryOzone()
@@ -76,6 +132,7 @@ bool InitializeDynamicGLBindings(GLImplementation implementation,
                                  GLContext* context) {
   switch (implementation) {
     case kGLImplementationOSMesaGL:
+    case kGLImplementationDesktopGL:
     case kGLImplementationEGLGLES2:
       InitializeDynamicGLBindingsGL(context);
       break;
@@ -85,8 +142,9 @@ bool InitializeDynamicGLBindings(GLImplementation implementation,
             new GLContextStubWithExtensions());
         mock_context->SetGLVersionString("3.0");
         InitializeDynamicGLBindingsGL(mock_context.get());
-      } else
+      } else {
         InitializeDynamicGLBindingsGL(context);
+      }
       break;
     default:
       return false;
@@ -96,17 +154,31 @@ bool InitializeDynamicGLBindings(GLImplementation implementation,
 }
 
 void InitializeDebugGLBindings() {
+  InitializeDebugGLBindingsEGL();
+  InitializeDebugGLBindingsGL();
+#if defined(USE_GLX)
+  InitializeDebugGLBindingsGLX();
+#endif
+  InitializeDebugGLBindingsOSMESA();
 }
 
 void ClearGLBindings() {
   ClearGLBindingsEGL();
   ClearGLBindingsGL();
+#if defined(USE_GLX)
+  ClearGLBindingsGLX();
+#endif
+  ClearGLBindingsOSMESA();
   SetGLImplementation(kGLImplementationNone);
   UnloadGLNativeLibraries();
 }
 
 bool GetGLWindowSystemBindingInfo(GLWindowSystemBindingInfo* info) {
   switch (GetGLImplementation()) {
+#if defined(USE_GLX)
+    case kGLImplementationDesktopGL:
+      return GetGLWindowSystemBindingInfoGLX(info);
+#endif
     case kGLImplementationEGLGLES2:
       return GetGLWindowSystemBindingInfoEGL(info);
     default: