1 files changed, 136 insertions, 0 deletions
diff --git a/gfx/config/gfxFeature.h b/gfx/config/gfxFeature.h
new file mode 100644
index 000000000..7e7734f6e
--- /dev/null
+++ b/gfx/config/gfxFeature.h
@@ -0,0 +1,136 @@
+/* -*- Mode: C++; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim: set sts=2 ts=8 sw=2 tw=99 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#ifndef mozilla_gfx_config_gfxFeature_h
+#define mozilla_gfx_config_gfxFeature_h
+
+#include <stdint.h>
+#include "gfxTelemetry.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Function.h"
+#include "nsString.h"
+
+namespace mozilla {
+namespace gfx {
+
+#define GFX_FEATURE_MAP(_)                                                        \
+  /* Name,                        Type,         Description */                    \
+  _(HW_COMPOSITING,               Feature,      "Compositing")                    \
+  _(D3D11_COMPOSITING,            Feature,      "Direct3D11 Compositing")         \
+  _(D3D9_COMPOSITING,             Feature,      "Direct3D9 Compositing")          \
+  _(OPENGL_COMPOSITING,           Feature,      "OpenGL Compositing")             \
+  _(DIRECT2D,                     Feature,      "Direct2D")                       \
+  _(D3D11_HW_ANGLE,               Feature,      "Direct3D11 hardware ANGLE")      \
+  _(DIRECT_DRAW,                  Feature,      "DirectDraw")                     \
+  _(GPU_PROCESS,                  Feature,      "GPU Process")                    \
+  /* Add new entries above this comment */
+
+enum class Feature : uint32_t {
+#define MAKE_ENUM(name, type, desc) name,
+  GFX_FEATURE_MAP(MAKE_ENUM)
+#undef MAKE_ENUM
+  NumValues
+};
+
+class FeatureState
+{
+  friend class gfxConfig;
+
+ public:
+  bool IsEnabled() const;
+  FeatureStatus GetValue() const;
+
+  void EnableByDefault();
+  void DisableByDefault(FeatureStatus aStatus, const char* aMessage, const nsACString& aFailureId);
+  bool SetDefault(bool aEnable, FeatureStatus aDisableStatus, const char* aDisableMessage);
+  bool InitOrUpdate(bool aEnable,
+                    FeatureStatus aDisableStatus,
+                    const char* aMessage);
+  void SetDefaultFromPref(const char* aPrefName,
+                          bool aIsEnablePref,
+                          bool aDefaultValue);
+  void UserEnable(const char* aMessage);
+  void UserForceEnable(const char* aMessage);
+  void UserDisable(const char* aMessage, const nsACString& aFailureId);
+  void Disable(FeatureStatus aStatus, const char* aMessage, const nsACString& aFailureId);
+  void ForceDisable(FeatureStatus aStatus, const char* aMessage, const nsACString& aFailureId) {
+    SetFailed(aStatus, aMessage, aFailureId);
+  }
+  void SetFailed(FeatureStatus aStatus, const char* aMessage, const nsACString& aFailureId);
+  bool MaybeSetFailed(bool aEnable, FeatureStatus aStatus, const char* aMessage, const nsACString& aFailureId);
+  bool MaybeSetFailed(FeatureStatus aStatus, const char* aMessage, const nsACString& aFailureId);
+
+  // aType is "base", "user", "env", or "runtime".
+  // aMessage may be null.
+  typedef mozilla::function<void(const char* aType,
+                                 FeatureStatus aStatus,
+                                 const char* aMessage)> StatusIterCallback;
+  void ForEachStatusChange(const StatusIterCallback& aCallback) const;
+
+  const char* GetFailureMessage() const;
+  const nsCString& GetFailureId() const;
+
+  bool DisabledByDefault() const;
+
+ private:
+  void SetUser(FeatureStatus aStatus, const char* aMessage);
+  void SetEnvironment(FeatureStatus aStatus, const char* aMessage);
+  void SetRuntime(FeatureStatus aStatus, const char* aMessage);
+  bool IsForcedOnByUser() const;
+  const char* GetRuntimeMessage() const;
+  bool IsInitialized() const {
+    return mDefault.IsInitialized();
+  }
+
+  void AssertInitialized() const {
+    MOZ_ASSERT(IsInitialized());
+  }
+
+  // Clear all state.
+  void Reset();
+
+ private:
+  void SetFailureId(const nsACString& aFailureId);
+
+  struct Instance {
+    char mMessage[64];
+    FeatureStatus mStatus;
+
+    void Set(FeatureStatus aStatus, const char* aMessage = nullptr);
+    bool IsInitialized() const {
+      return mStatus != FeatureStatus::Unused;
+    }
+    const char* MessageOrNull() const {
+      return mMessage[0] != '\0' ? mMessage : nullptr;
+    }
+    const char* Message() const {
+      MOZ_ASSERT(MessageOrNull());
+      return mMessage;
+    }
+  };
+
+  // The default state is the state we decide on startup, based on the operating
+  // system or a base preference.
+  //
+  // The user state factors in any changes to preferences that the user made.
+  //
+  // The environment state factors in any additional decisions made, such as
+  // availability or blacklisting.
+  //
+  // The runtime state factors in any problems discovered at runtime.
+  Instance mDefault;
+  Instance mUser;
+  Instance mEnvironment;
+  Instance mRuntime;
+
+  // Store the first reported failureId for now but we might want to track this
+  // by instance later if we need a specific breakdown.
+  nsCString mFailureId;
+};
+
+} // namespace gfx
+} // namespace mozilla
+
+#endif // mozilla_gfx_config_gfxFeature_h