Move CrossThreadCopier from platform/ to wtf/

third_party/WebKit/Source/platform/CrossThreadCopier.h

-/*
- * Copyright (C) 2009, 2010 Google Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef CrossThreadCopier_h
-#define CrossThreadCopier_h
-
-#include "platform/PlatformExport.h"
-#include "wtf/Assertions.h"
-#include "wtf/Forward.h"
-#include "wtf/Functional.h" // FunctionThreadAffinity
-#include "wtf/PassRefPtr.h"
-#include "wtf/RefPtr.h"
-#include "wtf/ThreadSafeRefCounted.h"
-#include "wtf/TypeTraits.h"
-#include <memory>
-
-class SkRefCnt;
-
-namespace WTF {
-
-template <typename T>
-class PassedWrapper;
-
-}
-
-namespace blink {
-
-class IntRect;
-class IntSize;
-class KURL;
-class ResourceError;
-class ResourceRequest;
-class ResourceResponse;
-struct CrossThreadResourceResponseData;
-struct CrossThreadResourceRequestData;
-template<typename T>class CrossThreadPersistent;
-template<typename T>class CrossThreadWeakPersistent;
-
-template <typename T>
-struct CrossThreadCopierPassThrough {
-    STATIC_ONLY(CrossThreadCopierPassThrough);
-    typedef T Type;
-    static Type copy(const T& parameter)
-    {
-        return parameter;
-    }
-};
-
-template <typename T, bool isArithmeticOrEnum>
-struct CrossThreadCopierBase;
-
-// Arithmetic values (integers or floats) and enums can be safely copied.
-template <typename T>
-struct CrossThreadCopierBase<T, true> : public CrossThreadCopierPassThrough<T> {
-    STATIC_ONLY(CrossThreadCopierBase);
-};
-
-template <typename T>
-struct CrossThreadCopier : public CrossThreadCopierBase<T, std::is_arithmetic<T>::value || std::is_enum<T>::value> {
-    STATIC_ONLY(CrossThreadCopier);
-};
-
-// CrossThreadCopier specializations follow.
-template <typename T>
-struct CrossThreadCopier<PassRefPtr<T>> : public CrossThreadCopierPassThrough<PassRefPtr<T>> {
-    STATIC_ONLY(CrossThreadCopier);
-    static_assert(WTF::IsSubclassOfTemplate<T, ThreadSafeRefCounted>::value || std::is_base_of<SkRefCnt, T>::value, "PassRefPtr<T> can be passed across threads only if T is ThreadSafeRefCounted or SkRefCnt.");
-};
-template <typename T>
-struct CrossThreadCopier<RefPtr<T>> : public CrossThreadCopierPassThrough<RefPtr<T>> {
-    STATIC_ONLY(CrossThreadCopier);
-    static_assert(WTF::IsSubclassOfTemplate<T, ThreadSafeRefCounted>::value || std::is_base_of<SkRefCnt, T>::value, "RefPtr<T> can be passed across threads only if T is ThreadSafeRefCounted or SkRefCnt.");
-};
-
-// nullptr_t can be passed through without any changes.
-template <>
-struct CrossThreadCopier<std::nullptr_t> : public CrossThreadCopierPassThrough<std::nullptr_t> {
-    STATIC_ONLY(CrossThreadCopier);
-};
-
-// To allow a type to be passed across threads using its copy constructor, add a forward declaration of the type and
-// provide a specialization of CrossThreadCopier<T> in this file, like IntRect below.
-template <>
-struct CrossThreadCopier<IntRect> : public CrossThreadCopierPassThrough<IntRect> {
-    STATIC_ONLY(CrossThreadCopier);
-};
-
-template <>
-struct CrossThreadCopier<IntSize> : public CrossThreadCopierPassThrough<IntSize> {
-    STATIC_ONLY(CrossThreadCopier);
-};
-
-template <typename T, typename Deleter>
-struct CrossThreadCopier<std::unique_ptr<T, Deleter>> {
-    STATIC_ONLY(CrossThreadCopier);
-    using Type = std::unique_ptr<T, Deleter>;
-    static std::unique_ptr<T, Deleter> copy(std::unique_ptr<T, Deleter> pointer)
-    {
-        return pointer; // This is in fact a move.
-    }
-};
-
-template<typename T>
-struct CrossThreadCopier<CrossThreadPersistent<T>> : public CrossThreadCopierPassThrough<CrossThreadPersistent<T>> {
-    STATIC_ONLY(CrossThreadCopier);
-};
-
-template<typename T>
-struct CrossThreadCopier<CrossThreadWeakPersistent<T>> : public CrossThreadCopierPassThrough<CrossThreadWeakPersistent<T>> {
-    STATIC_ONLY(CrossThreadCopier);
-};
-
-template<typename T>
-struct CrossThreadCopier<WTF::UnretainedWrapper<T, WTF::CrossThreadAffinity>> : public CrossThreadCopierPassThrough<WTF::UnretainedWrapper<T, WTF::CrossThreadAffinity>> {
-    STATIC_ONLY(CrossThreadCopier);
-};
-
-template<typename T>
-struct CrossThreadCopier<WeakPtr<T>> : public CrossThreadCopierPassThrough<WeakPtr<T>> {
-    STATIC_ONLY(CrossThreadCopier);
-};
-
-template <typename T>
-struct CrossThreadCopier<WTF::PassedWrapper<T>> {
-    STATIC_ONLY(CrossThreadCopier);
-    using Type = WTF::PassedWrapper<typename CrossThreadCopier<T>::Type>;
-    static Type copy(WTF::PassedWrapper<T>&& value) { return passed(CrossThreadCopier<T>::copy(value.moveOut())); }
-};
-
-template <>
-struct CrossThreadCopier<KURL> {
-    STATIC_ONLY(CrossThreadCopier);
-    typedef KURL Type;
-    PLATFORM_EXPORT static Type copy(const KURL&);
-};
-
-template <>
-struct CrossThreadCopier<String> {
-    STATIC_ONLY(CrossThreadCopier);
-    typedef String Type;
-    PLATFORM_EXPORT static Type copy(const String&);
-};
-
-template <>
-struct CrossThreadCopier<ResourceError> {
-    STATIC_ONLY(CrossThreadCopier);
-    typedef ResourceError Type;
-    PLATFORM_EXPORT static Type copy(const ResourceError&);
-};
-
-template <>
-struct CrossThreadCopier<ResourceRequest> {
-    STATIC_ONLY(CrossThreadCopier);
-    typedef WTF::PassedWrapper<std::unique_ptr<CrossThreadResourceRequestData>> Type;
-    PLATFORM_EXPORT static Type copy(const ResourceRequest&);
-};
-
-template <>
-struct CrossThreadCopier<ResourceResponse> {
-    STATIC_ONLY(CrossThreadCopier);
-    typedef WTF::PassedWrapper<std::unique_ptr<CrossThreadResourceResponseData>> Type;
-    PLATFORM_EXPORT static Type copy(const ResourceResponse&);
-};
-
-} // namespace blink
-
-#endif // CrossThreadCopier_h