Always use IOSGLContextSwitch to access EAGLContexts to prevent plu…

…gins from polluting Flutter's EAGLContext (#13314)

ci/licenses_golden/licenses_flutter

@@ -495,6 +495,8 @@ FILE: ../../../flutter/shell/common/canvas_spy_unittests.cc
 FILE: ../../../flutter/shell/common/engine.cc
 FILE: ../../../flutter/shell/common/engine.h
 FILE: ../../../flutter/shell/common/fixtures/shell_test.dart
+FILE: ../../../flutter/shell/common/gl_context_switch_manager.cc
+FILE: ../../../flutter/shell/common/gl_context_switch_manager.h
 FILE: ../../../flutter/shell/common/input_events_unittests.cc
 FILE: ../../../flutter/shell/common/isolate_configuration.cc
 FILE: ../../../flutter/shell/common/isolate_configuration.h
@@ -799,6 +801,8 @@ FILE: ../../../flutter/shell/platform/darwin/ios/ios_external_texture_gl.h
 FILE: ../../../flutter/shell/platform/darwin/ios/ios_external_texture_gl.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/ios_gl_context.h
 FILE: ../../../flutter/shell/platform/darwin/ios/ios_gl_context.mm
+FILE: ../../../flutter/shell/platform/darwin/ios/ios_gl_context_switch_manager.h
+FILE: ../../../flutter/shell/platform/darwin/ios/ios_gl_context_switch_manager.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/ios_gl_render_target.h
 FILE: ../../../flutter/shell/platform/darwin/ios/ios_gl_render_target.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/ios_surface.h

shell/common/BUILD.gn

@@ -66,6 +66,8 @@ source_set("common") {
     "canvas_spy.h",
     "engine.cc",
     "engine.h",
+    "gl_context_switch_manager.cc",
+    "gl_context_switch_manager.h",
     "isolate_configuration.cc",
     "isolate_configuration.h",
     "persistent_cache.cc",

shell/common/gl_context_switch_manager.cc

@@ -0,0 +1,28 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "gl_context_switch_manager.h"
+
+namespace flutter {
+
+GLContextSwitchManager::GLContextSwitchManager() = default;
+
+GLContextSwitchManager::~GLContextSwitchManager() = default;
+
+GLContextSwitchManager::GLContextSwitch::GLContextSwitch() = default;
+
+GLContextSwitchManager::GLContextSwitch::~GLContextSwitch(){};
+
+GLContextSwitchManager::GLContextSwitchPureResult::GLContextSwitchPureResult(
+    bool switch_result)
+    : switch_result_(switch_result){};
+
+GLContextSwitchManager::GLContextSwitchPureResult::
+    ~GLContextSwitchPureResult() = default;
+
+bool GLContextSwitchManager::GLContextSwitchPureResult::GetSwitchResult() {
+  return switch_result_;
+}
+
+}  // namespace flutter

shell/common/gl_context_switch_manager.h

@@ -0,0 +1,116 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef FLUTTER_SHELL_COMMON_GL_CONTEXT_SWITCH_MANAGER_H_
+#define FLUTTER_SHELL_COMMON_GL_CONTEXT_SWITCH_MANAGER_H_
+
+#include <memory>
+#include "flutter/fml/macros.h"
+
+namespace flutter {
+
+//------------------------------------------------------------------------------
+/// Manages `GLContextSwitch`.
+///
+/// Should be subclassed for platforms that uses GL and requires context
+/// switching. Always use `MakeCurrent` and `ResourceMakeCurrent` in the
+/// `GLContextSwitchManager` to set gl contexts.
+///
+class GLContextSwitchManager {
+ public:
+  //------------------------------------------------------------------------------
+  /// Switches the gl context to the flutter's contexts.
+  ///
+  /// Should be subclassed for each platform embedder that uses GL.
+  /// In construction, it should set the current context to a flutter's context
+  /// In destruction, it should rest the current context.
+  ///
+  class GLContextSwitch {
+   public:
+    GLContextSwitch();
+
+    virtual ~GLContextSwitch();
+
+    virtual bool GetSwitchResult() = 0;
+
+    FML_DISALLOW_COPY_AND_ASSIGN(GLContextSwitch);
+  };
+
+  GLContextSwitchManager();
+  ~GLContextSwitchManager();
+
+  //----------------------------------------------------------------------------
+  /// @brief      Creates a shell instance using the provided settings. The
+  ///             callbacks to create the various shell subcomponents will be
+  ///             called on the appropriate threads before this method returns.
+  ///             If this is the first instance of a shell in the process, this
+  ///             call also bootstraps the Dart VM.
+  ///
+  /// @param[in]  task_runners             The task runners
+  /// @param[in]  settings                 The settings
+  /// @param[in]  on_create_platform_view  The callback that must return a
+  ///                                      platform view. This will be called on
+  ///                                      the platform task runner before this
+  ///                                      method returns.
+  /// @param[in]  on_create_rasterizer     That callback that must provide a
+  ///                                      valid rasterizer. This will be called
+  ///                                      on the render task runner before this
+  ///                                      method returns.
+  ///
+  /// @return     A full initialized shell if the settings and callbacks are
+  ///             valid. The root isolate has been created but not yet launched.
+  ///             It may be launched by obtaining the engine weak pointer and
+  ///             posting a task onto the UI task runner with a valid run
+  ///             configuration to run the isolate. The embedder must always
+  ///             check the validity of the shell (using the IsSetup call)
+  ///             immediately after getting a pointer to it.
+  ///
+
+  //----------------------------------------------------------------------------
+  /// @brief      Make the flutter's context as current context.
+  ///
+  /// @return     A `GLContextSwitch` with `GetSwitchResult` returning true if
+  /// the setting process is succesful.
+  virtual std::unique_ptr<GLContextSwitch> MakeCurrent() = 0;
+
+  //----------------------------------------------------------------------------
+  /// @brief      Make the flutter's resources context as current context.
+  ///
+  /// @return     A `GLContextSwitch` with `GetSwitchResult` returning true if
+  /// the setting process is succesful.
+  virtual std::unique_ptr<GLContextSwitch> ResourceMakeCurrent() = 0;
+
+  //------------------------------------------------------------------------------
+  /// A representation of a `GLContextSwitch` that doesn't require actual
+  /// context switching.
+  ///
+  class GLContextSwitchPureResult final : public GLContextSwitch {
+   public:
+    // Constructor that creates an `GLContextSwitchPureResult`.
+    // The `GetSwitchResult` will return the same value as `switch_result`.
+
+    //----------------------------------------------------------------------------
+    /// @brief      Constructs a  `GLContextSwitchPureResult`.
+    ///
+    /// @param[in]  switch_result       the switch result that will be returned
+    /// in `GetSwitchResult()`
+    ///
+    GLContextSwitchPureResult(bool switch_result);
+
+    ~GLContextSwitchPureResult();
+
+    bool GetSwitchResult() override;
+
+   private:
+    bool switch_result_;
+
+    FML_DISALLOW_COPY_AND_ASSIGN(GLContextSwitchPureResult);
+  };
+
+  FML_DISALLOW_COPY_AND_ASSIGN(GLContextSwitchManager);
+};
+
+}  // namespace flutter
+
+#endif

shell/common/shell_test.cc

@@ -355,8 +355,10 @@ PointerDataDispatcherMaker ShellTestPlatformView::GetDispatcherMaker() {
 }
 
 // |GPUSurfaceGLDelegate|
-bool ShellTestPlatformView::GLContextMakeCurrent() {
-  return gl_surface_.MakeCurrent();
+std::unique_ptr<GLContextSwitchManager::GLContextSwitch>
+ShellTestPlatformView::GLContextMakeCurrent() {
+  return std::make_unique<GLContextSwitchManager::GLContextSwitchPureResult>(
+      gl_surface_.MakeCurrent());
 }
 
 // |GPUSurfaceGLDelegate|
@@ -387,5 +389,10 @@ ExternalViewEmbedder* ShellTestPlatformView::GetExternalViewEmbedder() {
   return nullptr;
 }
 
+std::shared_ptr<GLContextSwitchManager>
+ShellTestPlatformView::GetGLContextSwitchManager() {
+  return nullptr;
+}
+
 }  // namespace testing
 }  // namespace flutter

shell/common/shell_test.h

@@ -144,7 +144,8 @@ class ShellTestPlatformView : public PlatformView, public GPUSurfaceGLDelegate {
   PointerDataDispatcherMaker GetDispatcherMaker() override;
 
   // |GPUSurfaceGLDelegate|
-  bool GLContextMakeCurrent() override;
+  std::unique_ptr<GLContextSwitchManager::GLContextSwitch>
+  GLContextMakeCurrent() override;
 
   // |GPUSurfaceGLDelegate|
   bool GLContextClearCurrent() override;
@@ -161,6 +162,8 @@ class ShellTestPlatformView : public PlatformView, public GPUSurfaceGLDelegate {
   // |GPUSurfaceGLDelegate|
   ExternalViewEmbedder* GetExternalViewEmbedder() override;
 
+  std::shared_ptr<GLContextSwitchManager> GetGLContextSwitchManager() override;
+
   FML_DISALLOW_COPY_AND_ASSIGN(ShellTestPlatformView);
 };
 

shell/common/surface.cc

@@ -60,8 +60,10 @@ flutter::ExternalViewEmbedder* Surface::GetExternalViewEmbedder() {
   return nullptr;
 }
 
-bool Surface::MakeRenderContextCurrent() {
-  return true;
+std::unique_ptr<GLContextSwitchManager::GLContextSwitch>
+Surface::MakeRenderContextCurrent() {
+  return std::make_unique<GLContextSwitchManager::GLContextSwitchPureResult>(
+      true);
 }
 
 }  // namespace flutter

shell/common/surface.h

@@ -10,6 +10,7 @@
 #include "flutter/flow/compositor_context.h"
 #include "flutter/flow/embedded_views.h"
 #include "flutter/fml/macros.h"
+#include "flutter/shell/common/gl_context_switch_manager.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 
 namespace flutter {
@@ -58,7 +59,8 @@ class Surface {
 
   virtual flutter::ExternalViewEmbedder* GetExternalViewEmbedder();
 
-  virtual bool MakeRenderContextCurrent();
+  virtual std::unique_ptr<GLContextSwitchManager::GLContextSwitch>
+  MakeRenderContextCurrent();
 
  private:
   FML_DISALLOW_COPY_AND_ASSIGN(Surface);

shell/gpu/gpu_surface_gl.cc

@@ -8,6 +8,7 @@
 #include "flutter/fml/logging.h"
 #include "flutter/fml/size.h"
 #include "flutter/fml/trace_event.h"
+#include "flutter/shell/common/gl_context_switch_manager.h"
 #include "flutter/shell/common/persistent_cache.h"
 #include "third_party/skia/include/core/SkColorFilter.h"
 #include "third_party/skia/include/core/SkSurface.h"
@@ -39,7 +40,10 @@ GPUSurfaceGL::GPUSurfaceGL(GPUSurfaceGLDelegate* delegate,
     : delegate_(delegate),
       render_to_surface_(render_to_surface),
       weak_factory_(this) {
-  if (!delegate_->GLContextMakeCurrent()) {
+  std::unique_ptr<GLContextSwitchManager::GLContextSwitch> context_switch =
+      delegate_->GLContextMakeCurrent();
+
+  if (!context_switch->GetSwitchResult()) {
     FML_LOG(ERROR)
         << "Could not make the context current to setup the gr context.";
     return;
@@ -87,8 +91,6 @@ GPUSurfaceGL::GPUSurfaceGL(GPUSurfaceGLDelegate* delegate,
   }
   FML_LOG(INFO) << "Found " << caches.size() << " SkSL shaders; precompiled "
                 << compiled_count;
-
-  delegate_->GLContextClearCurrent();
 }
 
 GPUSurfaceGL::GPUSurfaceGL(sk_sp<GrContext> gr_context,
@@ -98,7 +100,9 @@ GPUSurfaceGL::GPUSurfaceGL(sk_sp<GrContext> gr_context,
       context_(gr_context),
       render_to_surface_(render_to_surface),
       weak_factory_(this) {
-  if (!delegate_->GLContextMakeCurrent()) {
+  std::unique_ptr<GLContextSwitchManager::GLContextSwitch> context_switch =
+      delegate_->GLContextMakeCurrent();
+  if (!context_switch->GetSwitchResult()) {
     FML_LOG(ERROR)
         << "Could not make the context current to setup the gr context.";
     return;
@@ -114,8 +118,9 @@ GPUSurfaceGL::~GPUSurfaceGL() {
   if (!valid_) {
     return;
   }
-
-  if (!delegate_->GLContextMakeCurrent()) {
+  std::unique_ptr<GLContextSwitchManager::GLContextSwitch> context_switch =
+      delegate_->GLContextMakeCurrent();
+  if (!context_switch->GetSwitchResult()) {
     FML_LOG(ERROR) << "Could not make the context current to destroy the "
                       "GrContext resources.";
     return;
@@ -126,8 +131,6 @@ GPUSurfaceGL::~GPUSurfaceGL() {
     context_->releaseResourcesAndAbandonContext();
   }
   context_ = nullptr;
-
-  delegate_->GLContextClearCurrent();
 }
 
 // |Surface|
@@ -253,7 +256,9 @@ std::unique_ptr<SurfaceFrame> GPUSurfaceGL::AcquireFrame(const SkISize& size) {
     return nullptr;
   }
 
-  if (!delegate_->GLContextMakeCurrent()) {
+  std::unique_ptr<GLContextSwitchManager::GLContextSwitch> context_switch =
+      delegate_->GLContextMakeCurrent();
+  if (!context_switch->GetSwitchResult()) {
     FML_LOG(ERROR)
         << "Could not make the context current to acquire the frame.";
     return nullptr;
@@ -285,14 +290,18 @@ std::unique_ptr<SurfaceFrame> GPUSurfaceGL::AcquireFrame(const SkISize& size) {
         return weak ? weak->PresentSurface(canvas) : false;
       };
 
-  return std::make_unique<SurfaceFrame>(surface, submit_callback);
+  std::unique_ptr<SurfaceFrame> result =
+      std::make_unique<SurfaceFrame>(surface, submit_callback);
+  return result;
 }
 
 bool GPUSurfaceGL::PresentSurface(SkCanvas* canvas) {
   if (delegate_ == nullptr || canvas == nullptr || context_ == nullptr) {
     return false;
   }
 
+  std::unique_ptr<GLContextSwitchManager::GLContextSwitch> context_switch =
+      delegate_->GLContextMakeCurrent();
   if (offscreen_surface_ != nullptr) {
     TRACE_EVENT0("flutter", "CopyTextureOnscreen");
     SkPaint paint;
@@ -329,7 +338,6 @@ bool GPUSurfaceGL::PresentSurface(SkCanvas* canvas) {
 
     onscreen_surface_ = std::move(new_onscreen_surface);
   }
-
   return true;
 }
 
@@ -360,7 +368,8 @@ flutter::ExternalViewEmbedder* GPUSurfaceGL::GetExternalViewEmbedder() {
 }
 
 // |Surface|
-bool GPUSurfaceGL::MakeRenderContextCurrent() {
+std::unique_ptr<GLContextSwitchManager::GLContextSwitch>
+GPUSurfaceGL::MakeRenderContextCurrent() {
   return delegate_->GLContextMakeCurrent();
 }
 

shell/gpu/gpu_surface_gl.h

@@ -44,7 +44,8 @@ class GPUSurfaceGL : public Surface {
   flutter::ExternalViewEmbedder* GetExternalViewEmbedder() override;
 
   // |Surface|
-  bool MakeRenderContextCurrent() override;
+  std::unique_ptr<GLContextSwitchManager::GLContextSwitch>
+  MakeRenderContextCurrent() override;
 
  private:
   GPUSurfaceGLDelegate* delegate_;

shell/gpu/gpu_surface_gl_delegate.h

@@ -7,6 +7,7 @@
 
 #include "flutter/flow/embedded_views.h"
 #include "flutter/fml/macros.h"
+#include "flutter/shell/common/gl_context_switch_manager.h"
 #include "flutter/shell/gpu/gpu_surface_delegate.h"
 #include "third_party/skia/include/core/SkMatrix.h"
 #include "third_party/skia/include/gpu/gl/GrGLInterface.h"
@@ -16,7 +17,8 @@ namespace flutter {
 class GPUSurfaceGLDelegate : public GPUSurfaceDelegate {
  public:
   // Called to make the main GL context current on the current thread.
-  virtual bool GLContextMakeCurrent() = 0;
+  virtual std::unique_ptr<GLContextSwitchManager::GLContextSwitch>
+  GLContextMakeCurrent() = 0;
 
   // Called to clear the current GL context on the thread. This may be called on
   // either the GPU or IO threads.
@@ -59,6 +61,9 @@ class GPUSurfaceGLDelegate : public GPUSurfaceDelegate {
   // instrumentation to specific GL calls can specify custom GL functions
   // here.
   virtual GLProcResolver GetGLProcResolver() const;
+
+  virtual std::shared_ptr<GLContextSwitchManager>
+  GetGLContextSwitchManager() = 0;
 };
 
 }  // namespace flutter