cross_thread_copier.h | Explore in Territory

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#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_CROSS_THREAD_COPIER_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_CROSS_THREAD_COPIER_H_

#include <type_traits>

#include "third_party/blink/renderer/platform/wtf/allocator/allocator.h"
#include "third_party/blink/renderer/platform/wtf/forward.h"
#include "third_party/blink/renderer/platform/wtf/wtf_size_t.h"

namespace WTF {

class String;

template <typename T>
struct CrossThreadCopierPassThrough { … };

template <typename T>
struct CrossThreadCopierByValuePassThrough { … };

template <typename T, bool isArithmeticOrEnum>
struct CrossThreadCopierBase;

// Arithmetic values (integers or floats) and enums can be safely copied.
CrossThreadCopierBase<T, true>;

template <typename T>
struct CrossThreadCopier
    : public CrossThreadCopierBase<T,
                                   std::is_arithmetic<T>::value ||
                                       std::is_enum<T>::value> { … };

// To allow a type to be passed across threads using its copy constructor,
// provide a specialization of CrossThreadCopier<T>.
//
// * If the type is not defined in third_party/blink/
//   ==> Choose one of the existing cross_thread_copier_*.h or add new one,
//       and add a forward declaration and a CrossThreadCopier specialization
//       for the type to the file.
// * If the type is defined in third_party/blink/public/
//   ==> Add a forward declaration and a CrossThreadCopier specialization for
//       the type to cross_thread_copier_public.h.
// * If the type is defined in third_party/blink/
//   ==> Include cross_thread_copier.h from the header defining the type, and
//       add a CrossThreadCopier specialization for the type to the header.

CrossThreadCopier<Vector<T, inlineCapacity, Allocator>>;

CrossThreadCopier<Vector<String, inlineCapacity, Allocator>>;

template <>
struct CrossThreadCopier<AtomicString>
    : public CrossThreadCopierPassThrough<AtomicString> { … };

template <>
struct CrossThreadCopier<String> : public CrossThreadCopierPassThrough<String> { … };

}  // namespace WTF

#endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_CROSS_THREAD_COPIER_H_
chromium/third_party/blink/renderer/platform/wtf/cross_thread_copier.h
