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-rw-r--r--third_party/chromium/base/callback_internal.h130
1 files changed, 1 insertions, 129 deletions
diff --git a/third_party/chromium/base/callback_internal.h b/third_party/chromium/base/callback_internal.h
index 3682bf9..d700794 100644
--- a/third_party/chromium/base/callback_internal.h
+++ b/third_party/chromium/base/callback_internal.h
@@ -8,17 +8,12 @@
#ifndef BASE_CALLBACK_INTERNAL_H_
#define BASE_CALLBACK_INTERNAL_H_
-#include <stddef.h>
-#include <map>
-#include <memory>
-#include <type_traits>
-#include <vector>
+#include <atomic>
#include "base/base_export.h"
#include "base/callback_forward.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
-#include "base/memory/scoped_ptr.h"
namespace base {
namespace internal {
@@ -117,129 +112,6 @@ class BASE_EXPORT CallbackBase<CopyMode::Copyable>
extern template class CallbackBase<CopyMode::MoveOnly>;
extern template class CallbackBase<CopyMode::Copyable>;
-// A helper template to determine if given type is non-const move-only-type,
-// i.e. if a value of the given type should be passed via std::move() in a
-// destructive way. Types are considered to be move-only if they have a
-// sentinel MoveOnlyTypeForCPP03 member: a class typically gets this from using
-// the DISALLOW_COPY_AND_ASSIGN_WITH_MOVE_FOR_BIND macro.
-// It would be easy to generalize this trait to all move-only types... but this
-// confuses template deduction in VS2013 with certain types such as
-// std::unique_ptr.
-// TODO(dcheng): Revisit this when Windows switches to VS2015 by default.
-
-template <typename T> struct IsMoveOnlyType {
- // Types YesType and NoType are guaranteed such that sizeof(YesType) <
- // sizeof(NoType).
- using YesType = char;
- struct NoType { YesType dummy[2]; };
-
- template <typename U>
- static YesType Test(const typename U::MoveOnlyTypeForCPP03*);
-
- template <typename U>
- static NoType Test(...);
-
- static const bool value = sizeof((Test<T>(0))) == sizeof(YesType) &&
- !std::is_const<T>::value;
-};
-
-// Specialization of IsMoveOnlyType so that std::unique_ptr is still considered
-// move-only, even without the sentinel member.
-template <typename T, typename D>
-struct IsMoveOnlyType<std::unique_ptr<T, D>> : std::true_type {};
-
-// Specialization of std::vector, so that it's considered move-only if the
-// element type is move-only. Allocator is explicitly ignored when determining
-// move-only status of the std::vector.
-template <typename T, typename Allocator>
-struct IsMoveOnlyType<std::vector<T, Allocator>> : IsMoveOnlyType<T> {};
-
-template <typename>
-struct CallbackParamTraitsForMoveOnlyType;
-
-template <typename>
-struct CallbackParamTraitsForNonMoveOnlyType;
-
-// TODO(tzik): Use a default parameter once MSVS supports variadic templates
-// with default values.
-// http://connect.microsoft.com/VisualStudio/feedbackdetail/view/957801/compilation-error-with-variadic-templates
-//
-// This is a typetraits object that's used to take an argument type, and
-// extract a suitable type for forwarding arguments.
-template <typename T>
-struct CallbackParamTraits
- : std::conditional<IsMoveOnlyType<T>::value,
- CallbackParamTraitsForMoveOnlyType<T>,
- CallbackParamTraitsForNonMoveOnlyType<T>>::type {
-};
-
-template <typename T>
-struct CallbackParamTraitsForNonMoveOnlyType {
- using ForwardType = const T&;
-};
-
-// Note that for array types, we implicitly add a const in the conversion. This
-// means that it is not possible to bind array arguments to functions that take
-// a non-const pointer. Trying to specialize the template based on a "const
-// T[n]" does not seem to match correctly, so we are stuck with this
-// restriction.
-template <typename T, size_t n>
-struct CallbackParamTraitsForNonMoveOnlyType<T[n]> {
- using ForwardType = const T*;
-};
-
-// See comment for CallbackParamTraits<T[n]>.
-template <typename T>
-struct CallbackParamTraitsForNonMoveOnlyType<T[]> {
- using ForwardType = const T*;
-};
-
-// Parameter traits for movable-but-not-copyable scopers.
-//
-// Callback<>/Bind() understands movable-but-not-copyable semantics where
-// the type cannot be copied but can still have its state destructively
-// transferred (aka. moved) to another instance of the same type by calling a
-// helper function. When used with Bind(), this signifies transferal of the
-// object's state to the target function.
-//
-// For these types, the ForwardType must not be a const reference, or a
-// reference. A const reference is inappropriate, and would break const
-// correctness, because we are implementing a destructive move. A non-const
-// reference cannot be used with temporaries which means the result of a
-// function or a cast would not be usable with Callback<> or Bind().
-template <typename T>
-struct CallbackParamTraitsForMoveOnlyType {
- using ForwardType = T;
-};
-
-// CallbackForward() is a very limited simulation of C++11's std::forward()
-// used by the Callback/Bind system for a set of movable-but-not-copyable
-// types. It is needed because forwarding a movable-but-not-copyable
-// argument to another function requires us to invoke the proper move
-// operator to create a rvalue version of the type. The supported types are
-// whitelisted below as overloads of the CallbackForward() function. The
-// default template compiles out to be a no-op.
-//
-// In C++11, std::forward would replace all uses of this function. However, it
-// is impossible to implement a general std::forward without C++11 due to a lack
-// of rvalue references.
-//
-// In addition to Callback/Bind, this is used by PostTaskAndReplyWithResult to
-// simulate std::forward() and forward the result of one Callback as a
-// parameter to another callback. This is to support Callbacks that return
-// the movable-but-not-copyable types whitelisted above.
-template <typename T>
-typename std::enable_if<!IsMoveOnlyType<T>::value, T>::type& CallbackForward(
- T& t) {
- return t;
-}
-
-template <typename T>
-typename std::enable_if<IsMoveOnlyType<T>::value, T>::type CallbackForward(
- T& t) {
- return std::move(t);
-}
-
} // namespace internal
} // namespace base