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Diffstat (limited to 'components/mus/public/cpp/window_property.h')
| -rw-r--r-- | components/mus/public/cpp/window_property.h | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/components/mus/public/cpp/window_property.h b/components/mus/public/cpp/window_property.h new file mode 100644 index 0000000..3d4df9e --- /dev/null +++ b/components/mus/public/cpp/window_property.h @@ -0,0 +1,140 @@ +// Copyright 2014 The Chromium 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 COMPONENTS_MUS_PUBLIC_CPP_WINDOW_PROPERTY_H_ +#define COMPONENTS_MUS_PUBLIC_CPP_WINDOW_PROPERTY_H_ + +#include <stdint.h> + +// This header should be included by code that defines WindowProperties. It +// should not be included by code that only gets and sets WindowProperties. +// +// To define a new WindowProperty: +// +// #include "components/mus/public/cpp/window_property.h" +// +// DECLARE_EXPORTED_WINDOW_PROPERTY_TYPE(FOO_EXPORT, MyType); +// namespace foo { +// // Use this to define an exported property that is primitive, +// // or a pointer you don't want automatically deleted. +// DEFINE_WINDOW_PROPERTY_KEY(MyType, kMyKey, MyDefault); +// +// // Use this to define an exported property whose value is a heap +// // allocated object, and has to be owned and freed by the view. +// DEFINE_OWNED_WINDOW_PROPERTY_KEY(gfx::Rect, kRestoreBoundsKey, nullptr); +// +// // Use this to define a non exported property that is primitive, +// // or a pointer you don't want to automatically deleted, and is used +// // only in a specific file. This will define the property in an unnamed +// // namespace which cannot be accessed from another file. +// DEFINE_LOCAL_WINDOW_PROPERTY_KEY(MyType, kMyKey, MyDefault); +// +// } // foo namespace +// +// To define a new type used for WindowProperty. +// +// // outside all namespaces: +// DECLARE_EXPORTED_WINDOW_PROPERTY_TYPE(FOO_EXPORT, MyType) +// +// If a property type is not exported, use DECLARE_WINDOW_PROPERTY_TYPE(MyType) +// which is a shorthand for DECLARE_EXPORTED_WINDOW_PROPERTY_TYPE(, MyType). + +namespace mus { +namespace { + +// No single new-style cast works for every conversion to/from int64_t, so we +// need this helper class. A third specialization is needed for bool because +// MSVC warning C4800 (forcing value to bool) is not suppressed by an explicit +// cast (!). +template <typename T> +class WindowPropertyCaster { + public: + static int64_t ToInt64(T x) { return static_cast<int64_t>(x); } + static T FromInt64(int64_t x) { return static_cast<T>(x); } +}; +template <typename T> +class WindowPropertyCaster<T*> { + public: + static int64_t ToInt64(T* x) { return reinterpret_cast<int64_t>(x); } + static T* FromInt64(int64_t x) { return reinterpret_cast<T*>(x); } +}; +template <> +class WindowPropertyCaster<bool> { + public: + static int64_t ToInt64(bool x) { return static_cast<int64_t>(x); } + static bool FromInt64(int64_t x) { return x != 0; } +}; + +} // namespace + +template <typename T> +struct WindowProperty { + T default_value; + const char* name; + Window::PropertyDeallocator deallocator; +}; + +template <typename T> +void Window::SetLocalProperty(const WindowProperty<T>* property, T value) { + int64_t old = SetLocalPropertyInternal( + property, property->name, + value == property->default_value ? nullptr : property->deallocator, + WindowPropertyCaster<T>::ToInt64(value), + WindowPropertyCaster<T>::ToInt64(property->default_value)); + if (property->deallocator && + old != WindowPropertyCaster<T>::ToInt64(property->default_value)) { + (*property->deallocator)(old); + } +} + +template <typename T> +T Window::GetLocalProperty(const WindowProperty<T>* property) const { + return WindowPropertyCaster<T>::FromInt64(GetLocalPropertyInternal( + property, WindowPropertyCaster<T>::ToInt64(property->default_value))); +} + +template <typename T> +void Window::ClearLocalProperty(const WindowProperty<T>* property) { + SetLocalProperty(property, property->default_value); +} + +} // namespace mus + +// Macros to instantiate the property getter/setter template functions. +#define DECLARE_EXPORTED_WINDOW_PROPERTY_TYPE(EXPORT, T) \ + template EXPORT void mus::Window::SetLocalProperty( \ + const mus::WindowProperty<T>*, T); \ + template EXPORT T mus::Window::GetLocalProperty( \ + const mus::WindowProperty<T>*) const; \ + template EXPORT void mus::Window::ClearLocalProperty( \ + const mus::WindowProperty<T>*); +#define DECLARE_WINDOW_PROPERTY_TYPE(T) \ + DECLARE_EXPORTED_WINDOW_PROPERTY_TYPE(, T) + +#define DEFINE_WINDOW_PROPERTY_KEY(TYPE, NAME, DEFAULT) \ + COMPILE_ASSERT(sizeof(TYPE) <= sizeof(int64_t), property_type_too_large); \ + namespace { \ + const mus::WindowProperty<TYPE> NAME##_Value = {DEFAULT, #NAME, nullptr}; \ + } \ + const mus::WindowProperty<TYPE>* const NAME = &NAME##_Value; + +#define DEFINE_LOCAL_WINDOW_PROPERTY_KEY(TYPE, NAME, DEFAULT) \ + COMPILE_ASSERT(sizeof(TYPE) <= sizeof(int64_t), property_type_too_large); \ + namespace { \ + const mus::WindowProperty<TYPE> NAME##_Value = {DEFAULT, #NAME, nullptr}; \ + const mus::WindowProperty<TYPE>* const NAME = &NAME##_Value; \ + } + +#define DEFINE_OWNED_WINDOW_PROPERTY_KEY(TYPE, NAME, DEFAULT) \ + namespace { \ + void Deallocator##NAME(int64_t p) { \ + enum { type_must_be_complete = sizeof(TYPE) }; \ + delete mus::WindowPropertyCaster<TYPE*>::FromInt64(p); \ + } \ + const mus::WindowProperty<TYPE*> NAME##_Value = {DEFAULT, #NAME, \ + &Deallocator##NAME}; \ + } \ + const mus::WindowProperty<TYPE*>* const NAME = &NAME##_Value; + +#endif // COMPONENTS_MUS_PUBLIC_CPP_WINDOW_PROPERTY_H_ |