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806 lines
27 KiB
C++
806 lines
27 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set ts=8 sts=2 et sw=2 tw=80: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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/* Smart pointer managing sole ownership of a resource. */
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#ifndef mozilla_UniquePtr_h
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#define mozilla_UniquePtr_h
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#include "mozilla/Assertions.h"
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#include "mozilla/Attributes.h"
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#include "mozilla/Compiler.h"
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#include "mozilla/Move.h"
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#include "mozilla/NullPtr.h"
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#include "mozilla/Pair.h"
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#include "mozilla/TypeTraits.h"
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namespace mozilla {
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template<typename T> class DefaultDelete;
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template<typename T, class D = DefaultDelete<T>> class UniquePtr;
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} // namespace mozilla
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namespace mozilla {
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/**
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* UniquePtr is a smart pointer that wholly owns a resource. Ownership may be
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* transferred out of a UniquePtr through explicit action, but otherwise the
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* resource is destroyed when the UniquePtr is destroyed.
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*
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* UniquePtr is similar to C++98's std::auto_ptr, but it improves upon auto_ptr
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* in one crucial way: it's impossible to copy a UniquePtr. Copying an auto_ptr
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* obviously *can't* copy ownership of its singly-owned resource. So what
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* happens if you try to copy one? Bizarrely, ownership is implicitly
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* *transferred*, preserving single ownership but breaking code that assumes a
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* copy of an object is identical to the original. (This is why auto_ptr is
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* prohibited in STL containers.)
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*
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* UniquePtr solves this problem by being *movable* rather than copyable.
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* Instead of passing a |UniquePtr u| directly to the constructor or assignment
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* operator, you pass |Move(u)|. In doing so you indicate that you're *moving*
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* ownership out of |u|, into the target of the construction/assignment. After
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* the transfer completes, |u| contains |nullptr| and may be safely destroyed.
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* This preserves single ownership but also allows UniquePtr to be moved by
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* algorithms that have been made move-safe. (Note: if |u| is instead a
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* temporary expression, don't use |Move()|: just pass the expression, because
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* it's already move-ready. For more information see Move.h.)
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*
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* UniquePtr is also better than std::auto_ptr in that the deletion operation is
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* customizable. An optional second template parameter specifies a class that
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* (through its operator()(T*)) implements the desired deletion policy. If no
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* policy is specified, mozilla::DefaultDelete<T> is used -- which will either
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* |delete| or |delete[]| the resource, depending whether the resource is an
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* array. Custom deletion policies ideally should be empty classes (no member
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* fields, no member fields in base classes, no virtual methods/inheritance),
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* because then UniquePtr can be just as efficient as a raw pointer.
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*
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* Use of UniquePtr proceeds like so:
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*
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* UniquePtr<int> g1; // initializes to nullptr
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* g1.reset(new int); // switch resources using reset()
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* g1 = nullptr; // clears g1, deletes the int
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*
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* UniquePtr<int> g2(new int); // owns that int
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* int* p = g2.release(); // g2 leaks its int -- still requires deletion
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* delete p; // now freed
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*
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* struct S { int x; S(int x) : x(x) {} };
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* UniquePtr<S> g3, g4(new S(5));
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* g3 = Move(g4); // g3 owns the S, g4 cleared
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* S* p = g3.get(); // g3 still owns |p|
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* assert(g3->x == 5); // operator-> works (if .get() != nullptr)
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* assert((*g3).x == 5); // also operator* (again, if not cleared)
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* Swap(g3, g4); // g4 now owns the S, g3 cleared
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* g3.swap(g4); // g3 now owns the S, g4 cleared
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* UniquePtr<S> g5(Move(g3)); // g5 owns the S, g3 cleared
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* g5.reset(); // deletes the S, g5 cleared
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*
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* struct FreePolicy { void operator()(void* p) { free(p); } };
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* UniquePtr<int, FreePolicy> g6(static_cast<int*>(malloc(sizeof(int))));
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* int* ptr = g6.get();
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* g6 = nullptr; // calls free(ptr)
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*
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* Now, carefully note a few things you *can't* do:
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*
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* UniquePtr<int> b1;
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* b1 = new int; // BAD: can only assign another UniquePtr
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* int* ptr = b1; // BAD: no auto-conversion to pointer, use get()
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*
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* UniquePtr<int> b2(b1); // BAD: can't copy a UniquePtr
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* UniquePtr<int> b3 = b1; // BAD: can't copy-assign a UniquePtr
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*
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* (Note that changing a UniquePtr to store a direct |new| expression is
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* permitted, but usually you should use MakeUnique, defined at the end of this
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* header.)
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*
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* A few miscellaneous notes:
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*
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* UniquePtr, when not instantiated for an array type, can be move-constructed
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* and move-assigned, not only from itself but from "derived" UniquePtr<U, E>
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* instantiations where U converts to T and E converts to D. If you want to use
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* this, you're going to have to specify a deletion policy for both UniquePtr
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* instantations, and T pretty much has to have a virtual destructor. In other
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* words, this doesn't work:
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*
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* struct Base { virtual ~Base() {} };
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* struct Derived : Base {};
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*
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* UniquePtr<Base> b1;
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* // BAD: DefaultDelete<Base> and DefaultDelete<Derived> don't interconvert
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* UniquePtr<Derived> d1(Move(b));
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*
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* UniquePtr<Base> b2;
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* UniquePtr<Derived, DefaultDelete<Base>> d2(Move(b2)); // okay
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*
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* UniquePtr is specialized for array types. Specializing with an array type
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* creates a smart-pointer version of that array -- not a pointer to such an
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* array.
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*
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* UniquePtr<int[]> arr(new int[5]);
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* arr[0] = 4;
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*
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* What else is different? Deletion of course uses |delete[]|. An operator[]
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* is provided. Functionality that doesn't make sense for arrays is removed.
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* The constructors and mutating methods only accept array pointers (not T*, U*
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* that converts to T*, or UniquePtr<U[]> or UniquePtr<U>) or |nullptr|.
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*
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* It's perfectly okay to return a UniquePtr from a method to assure the related
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* resource is properly deleted. You'll need to use |Move()| when returning a
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* local UniquePtr. Otherwise you can return |nullptr|, or you can return
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* |UniquePtr(ptr)|.
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*
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* UniquePtr will commonly be a member of a class, with lifetime equivalent to
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* that of that class. If you want to expose the related resource, you could
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* expose a raw pointer via |get()|, but ownership of a raw pointer is
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* inherently unclear. So it's better to expose a |const UniquePtr&| instead.
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* This prohibits mutation but still allows use of |get()| when needed (but
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* operator-> is preferred). Of course, you can only use this smart pointer as
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* long as the enclosing class instance remains live -- no different than if you
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* exposed the |get()| raw pointer.
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*
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* To pass a UniquePtr-managed resource as a pointer, use a |const UniquePtr&|
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* argument. To specify an inout parameter (where the method may or may not
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* take ownership of the resource, or reset it), or to specify an out parameter
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* (where simply returning a |UniquePtr| isn't possible), use a |UniquePtr&|
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* argument. To unconditionally transfer ownership of a UniquePtr
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* into a method, use a |UniquePtr| argument. To conditionally transfer
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* ownership of a resource into a method, should the method want it, use a
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* |UniquePtr&&| argument.
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*/
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template<typename T, class D>
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class UniquePtr
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{
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public:
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typedef T* Pointer;
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typedef T ElementType;
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typedef D DeleterType;
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private:
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Pair<Pointer, DeleterType> mTuple;
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Pointer& ptr() { return mTuple.first(); }
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const Pointer& ptr() const { return mTuple.first(); }
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DeleterType& del() { return mTuple.second(); }
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const DeleterType& del() const { return mTuple.second(); }
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public:
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/**
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* Construct a UniquePtr containing |nullptr|.
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*/
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MOZ_CONSTEXPR UniquePtr()
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: mTuple(static_cast<Pointer>(nullptr), DeleterType())
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{
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static_assert(!IsPointer<D>::value, "must provide a deleter instance");
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static_assert(!IsReference<D>::value, "must provide a deleter instance");
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}
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/**
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* Construct a UniquePtr containing |aPtr|.
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*/
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explicit UniquePtr(Pointer aPtr)
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: mTuple(aPtr, DeleterType())
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{
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static_assert(!IsPointer<D>::value, "must provide a deleter instance");
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static_assert(!IsReference<D>::value, "must provide a deleter instance");
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}
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UniquePtr(Pointer aPtr,
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typename Conditional<IsReference<D>::value,
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D,
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const D&>::Type aD1)
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: mTuple(aPtr, aD1)
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{}
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// If you encounter an error with MSVC10 about RemoveReference below, along
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// the lines that "more than one partial specialization matches the template
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// argument list": don't use UniquePtr<T, reference to function>! Ideally
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// you should make deletion use the same function every time, using a
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// deleter policy:
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//
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// // BAD, won't compile with MSVC10, deleter doesn't need to be a
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// // variable at all
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// typedef void (&FreeSignature)(void*);
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// UniquePtr<int, FreeSignature> ptr((int*) malloc(sizeof(int)), free);
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//
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// // GOOD, compiles with MSVC10, deletion behavior statically known and
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// // optimizable
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// struct DeleteByFreeing
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// {
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// void operator()(void* aPtr) { free(aPtr); }
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// };
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//
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// If deletion really, truly, must be a variable: you might be able to work
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// around this with a deleter class that contains the function reference.
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// But this workaround is untried and untested, because variable deletion
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// behavior really isn't something you should use.
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UniquePtr(Pointer aPtr,
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typename RemoveReference<D>::Type&& aD2)
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: mTuple(aPtr, Move(aD2))
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{
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static_assert(!IsReference<D>::value,
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"rvalue deleter can't be stored by reference");
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}
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UniquePtr(UniquePtr&& aOther)
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: mTuple(aOther.release(), Forward<DeleterType>(aOther.getDeleter()))
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{}
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template<typename N>
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UniquePtr(N,
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typename EnableIf<IsNullPointer<N>::value, int>::Type aDummy = 0)
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: mTuple(static_cast<Pointer>(nullptr), DeleterType())
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{
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static_assert(!IsPointer<D>::value, "must provide a deleter instance");
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static_assert(!IsReference<D>::value, "must provide a deleter instance");
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}
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template<typename U, class E>
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UniquePtr(UniquePtr<U, E>&& aOther,
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typename EnableIf<IsConvertible<typename UniquePtr<U, E>::Pointer,
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Pointer>::value &&
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!IsArray<U>::value &&
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(IsReference<D>::value
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? IsSame<D, E>::value
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: IsConvertible<E, D>::value),
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int>::Type aDummy = 0)
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: mTuple(aOther.release(), Forward<E>(aOther.getDeleter()))
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{
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}
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~UniquePtr() { reset(nullptr); }
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UniquePtr& operator=(UniquePtr&& aOther)
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{
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reset(aOther.release());
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getDeleter() = Forward<DeleterType>(aOther.getDeleter());
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return *this;
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}
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template<typename U, typename E>
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UniquePtr& operator=(UniquePtr<U, E>&& aOther)
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{
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static_assert(IsConvertible<typename UniquePtr<U, E>::Pointer,
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Pointer>::value,
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"incompatible UniquePtr pointees");
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static_assert(!IsArray<U>::value,
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"can't assign from UniquePtr holding an array");
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reset(aOther.release());
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getDeleter() = Forward<E>(aOther.getDeleter());
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return *this;
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}
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UniquePtr& operator=(NullptrT aNull)
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{
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MOZ_ASSERT(aNull == nullptr);
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reset(nullptr);
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return *this;
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}
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T& operator*() const { return *get(); }
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Pointer operator->() const
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{
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MOZ_ASSERT(get(), "dereferencing a UniquePtr containing nullptr");
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return get();
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}
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Pointer get() const { return ptr(); }
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DeleterType& getDeleter() { return del(); }
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const DeleterType& getDeleter() const { return del(); }
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private:
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typedef void (UniquePtr::* ConvertibleToBool)(double, char);
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void nonNull(double, char) {}
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public:
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operator ConvertibleToBool() const
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{
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return get() != nullptr ? &UniquePtr::nonNull : nullptr;
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}
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Pointer release()
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{
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Pointer p = ptr();
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ptr() = nullptr;
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return p;
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}
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void reset(Pointer aPtr = Pointer())
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{
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Pointer old = ptr();
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ptr() = aPtr;
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if (old != nullptr) {
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getDeleter()(old);
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}
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}
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void swap(UniquePtr& aOther)
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{
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mTuple.swap(aOther.mTuple);
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}
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private:
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UniquePtr(const UniquePtr& aOther) MOZ_DELETE; // construct using Move()!
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void operator=(const UniquePtr& aOther) MOZ_DELETE; // assign using Move()!
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};
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// In case you didn't read the comment by the main definition (you should!): the
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// UniquePtr<T[]> specialization exists to manage array pointers. It deletes
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// such pointers using delete[], it will reject construction and modification
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// attempts using U* or U[]. Otherwise it works like the normal UniquePtr.
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template<typename T, class D>
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class UniquePtr<T[], D>
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{
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public:
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typedef T* Pointer;
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typedef T ElementType;
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typedef D DeleterType;
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private:
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Pair<Pointer, DeleterType> mTuple;
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public:
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/**
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* Construct a UniquePtr containing nullptr.
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*/
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MOZ_CONSTEXPR UniquePtr()
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: mTuple(static_cast<Pointer>(nullptr), DeleterType())
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{
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static_assert(!IsPointer<D>::value, "must provide a deleter instance");
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static_assert(!IsReference<D>::value, "must provide a deleter instance");
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}
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/**
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* Construct a UniquePtr containing |aPtr|.
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*/
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explicit UniquePtr(Pointer aPtr)
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: mTuple(aPtr, DeleterType())
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{
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static_assert(!IsPointer<D>::value, "must provide a deleter instance");
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static_assert(!IsReference<D>::value, "must provide a deleter instance");
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}
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private:
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// delete[] knows how to handle *only* an array of a single class type. For
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// delete[] to work correctly, it must know the size of each element, the
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// fields and base classes of each element requiring destruction, and so on.
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// So forbid all overloads which would end up invoking delete[] on a pointer
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// of the wrong type.
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template<typename U>
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UniquePtr(U&& aU,
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typename EnableIf<IsPointer<U>::value &&
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IsConvertible<U, Pointer>::value,
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int>::Type aDummy = 0)
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MOZ_DELETE;
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public:
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UniquePtr(Pointer aPtr,
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typename Conditional<IsReference<D>::value,
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D,
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const D&>::Type aD1)
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: mTuple(aPtr, aD1)
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{}
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// If you encounter an error with MSVC10 about RemoveReference below, along
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// the lines that "more than one partial specialization matches the template
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// argument list": don't use UniquePtr<T[], reference to function>! See the
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// comment by this constructor in the non-T[] specialization above.
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UniquePtr(Pointer aPtr,
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typename RemoveReference<D>::Type&& aD2)
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: mTuple(aPtr, Move(aD2))
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{
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static_assert(!IsReference<D>::value,
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"rvalue deleter can't be stored by reference");
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}
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private:
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// Forbidden for the same reasons as stated above.
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template<typename U, typename V>
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UniquePtr(U&& aU, V&& aV,
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typename EnableIf<IsPointer<U>::value &&
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IsConvertible<U, Pointer>::value,
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int>::Type aDummy = 0)
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MOZ_DELETE;
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public:
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UniquePtr(UniquePtr&& aOther)
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: mTuple(aOther.release(), Forward<DeleterType>(aOther.getDeleter()))
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{}
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template<typename N>
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UniquePtr(N,
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typename EnableIf<IsNullPointer<N>::value, int>::Type aDummy = 0)
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: mTuple(static_cast<Pointer>(nullptr), DeleterType())
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{
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static_assert(!IsPointer<D>::value, "must provide a deleter instance");
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static_assert(!IsReference<D>::value, "must provide a deleter instance");
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}
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~UniquePtr() { reset(nullptr); }
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UniquePtr& operator=(UniquePtr&& aOther)
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{
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reset(aOther.release());
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getDeleter() = Forward<DeleterType>(aOther.getDeleter());
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return *this;
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}
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UniquePtr& operator=(NullptrT)
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{
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reset();
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return *this;
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}
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T& operator[](decltype(sizeof(int)) aIndex) const { return get()[aIndex]; }
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Pointer get() const { return mTuple.first(); }
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DeleterType& getDeleter() { return mTuple.second(); }
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const DeleterType& getDeleter() const { return mTuple.second(); }
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private:
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typedef void (UniquePtr::* ConvertibleToBool)(double, char);
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void nonNull(double, char) {}
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public:
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operator ConvertibleToBool() const
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{
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return get() != nullptr ? &UniquePtr::nonNull : nullptr;
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}
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Pointer release()
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{
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Pointer p = mTuple.first();
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mTuple.first() = nullptr;
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return p;
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}
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void reset(Pointer aPtr = Pointer())
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{
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Pointer old = mTuple.first();
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mTuple.first() = aPtr;
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if (old != nullptr) {
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mTuple.second()(old);
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}
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}
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private:
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// Kill off all remaining overloads that aren't true nullptr (the overload
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// above should handle that) or emulated nullptr (which acts like int/long
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// on gcc 4.4/4.5).
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template<typename U>
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void reset(U,
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typename EnableIf<!IsNullPointer<U>::value &&
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!IsSame<U,
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Conditional<(sizeof(int) == sizeof(void*)),
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int,
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long>::Type>::value,
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int>::Type aDummy = 0)
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MOZ_DELETE;
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public:
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void swap(UniquePtr& aOther) { mTuple.swap(aOther.mTuple); }
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private:
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UniquePtr(const UniquePtr& aOther) MOZ_DELETE; // construct using Move()!
|
|
void operator=(const UniquePtr& aOther) MOZ_DELETE; // assign using Move()!
|
|
};
|
|
|
|
/** A default deletion policy using plain old operator delete. */
|
|
template<typename T>
|
|
class DefaultDelete
|
|
{
|
|
public:
|
|
MOZ_CONSTEXPR DefaultDelete() {}
|
|
|
|
template<typename U>
|
|
DefaultDelete(const DefaultDelete<U>& aOther,
|
|
typename EnableIf<mozilla::IsConvertible<U*, T*>::value,
|
|
int>::Type aDummy = 0)
|
|
{}
|
|
|
|
void operator()(T* aPtr) const
|
|
{
|
|
static_assert(sizeof(T) > 0, "T must be complete");
|
|
delete aPtr;
|
|
}
|
|
};
|
|
|
|
/** A default deletion policy using operator delete[]. */
|
|
template<typename T>
|
|
class DefaultDelete<T[]>
|
|
{
|
|
public:
|
|
MOZ_CONSTEXPR DefaultDelete() {}
|
|
|
|
void operator()(T* aPtr) const
|
|
{
|
|
static_assert(sizeof(T) > 0, "T must be complete");
|
|
delete[] aPtr;
|
|
}
|
|
|
|
private:
|
|
template<typename U>
|
|
void operator()(U* aPtr) const MOZ_DELETE;
|
|
};
|
|
|
|
template<typename T, class D>
|
|
void
|
|
Swap(UniquePtr<T, D>& aX, UniquePtr<T, D>& aY)
|
|
{
|
|
aX.swap(aY);
|
|
}
|
|
|
|
template<typename T, class D, typename U, class E>
|
|
bool
|
|
operator==(const UniquePtr<T, D>& aX, const UniquePtr<U, E>& aY)
|
|
{
|
|
return aX.get() == aY.get();
|
|
}
|
|
|
|
template<typename T, class D, typename U, class E>
|
|
bool
|
|
operator!=(const UniquePtr<T, D>& aX, const UniquePtr<U, E>& aY)
|
|
{
|
|
return aX.get() != aY.get();
|
|
}
|
|
|
|
template<typename T, class D>
|
|
bool
|
|
operator==(const UniquePtr<T, D>& aX, NullptrT aNull)
|
|
{
|
|
MOZ_ASSERT(aNull == nullptr);
|
|
return !aX;
|
|
}
|
|
|
|
template<typename T, class D>
|
|
bool
|
|
operator==(NullptrT aNull, const UniquePtr<T, D>& aX)
|
|
{
|
|
MOZ_ASSERT(aNull == nullptr);
|
|
return !aX;
|
|
}
|
|
|
|
template<typename T, class D>
|
|
bool
|
|
operator!=(const UniquePtr<T, D>& aX, NullptrT aNull)
|
|
{
|
|
MOZ_ASSERT(aNull == nullptr);
|
|
return bool(aX);
|
|
}
|
|
|
|
template<typename T, class D>
|
|
bool
|
|
operator!=(NullptrT aNull, const UniquePtr<T, D>& aX)
|
|
{
|
|
MOZ_ASSERT(aNull == nullptr);
|
|
return bool(aX);
|
|
}
|
|
|
|
// No operator<, operator>, operator<=, operator>= for now because simplicity.
|
|
|
|
namespace detail {
|
|
|
|
template<typename T>
|
|
struct UniqueSelector
|
|
{
|
|
typedef UniquePtr<T> SingleObject;
|
|
};
|
|
|
|
template<typename T>
|
|
struct UniqueSelector<T[]>
|
|
{
|
|
typedef UniquePtr<T[]> UnknownBound;
|
|
};
|
|
|
|
template<typename T, decltype(sizeof(int)) N>
|
|
struct UniqueSelector<T[N]>
|
|
{
|
|
typedef UniquePtr<T[N]> KnownBound;
|
|
};
|
|
|
|
} // namespace detail
|
|
|
|
/**
|
|
* MakeUnique is a helper function for allocating new'd objects and arrays,
|
|
* returning a UniquePtr containing the resulting pointer. The semantics of
|
|
* MakeUnique<Type>(...) are as follows.
|
|
*
|
|
* If Type is an array T[n]:
|
|
* Disallowed, deleted, no overload for you!
|
|
* If Type is an array T[]:
|
|
* MakeUnique<T[]>(size_t) is the only valid overload. The pointer returned
|
|
* is as if by |new T[n]()|, which value-initializes each element. (If T
|
|
* isn't a class type, this will zero each element. If T is a class type,
|
|
* then roughly speaking, each element will be constructed using its default
|
|
* constructor. See C++11 [dcl.init]p7 for the full gory details.)
|
|
* If Type is non-array T:
|
|
* The arguments passed to MakeUnique<T>(...) are forwarded into a
|
|
* |new T(...)| call, initializing the T as would happen if executing
|
|
* |T(...)|. (Note: literal nullptr must not be provided as an argument to
|
|
* MakeUnique, because nullptr may be emulated. See Move.h for details.)
|
|
*
|
|
* There are various benefits to using MakeUnique instead of |new| expressions.
|
|
*
|
|
* First, MakeUnique eliminates use of |new| from code entirely. If objects are
|
|
* only created through UniquePtr, then (assuming all explicit release() calls
|
|
* are safe, including transitively, and no type-safety casting funniness)
|
|
* correctly maintained ownership of the UniquePtr guarantees no leaks are
|
|
* possible. (This pays off best if a class is only ever created through a
|
|
* factory method on the class, using a private constructor.)
|
|
*
|
|
* Second, initializing a UniquePtr using a |new| expression requires renaming
|
|
* the new'd type, whereas MakeUnique in concert with the |auto| keyword names
|
|
* it only once:
|
|
*
|
|
* UniquePtr<char> ptr1(new char()); // repetitive
|
|
* auto ptr2 = MakeUnique<char>(); // shorter
|
|
*
|
|
* Of course this assumes the reader understands the operation MakeUnique
|
|
* performs. In the long run this is probably a reasonable assumption. In the
|
|
* short run you'll have to use your judgment about what readers can be expected
|
|
* to know, or to quickly look up.
|
|
*
|
|
* Third, a call to MakeUnique can be assigned directly to a UniquePtr. In
|
|
* contrast you can't assign a pointer into a UniquePtr without using the
|
|
* cumbersome reset().
|
|
*
|
|
* UniquePtr<char> p;
|
|
* p = new char; // ERROR
|
|
* p.reset(new char); // works, but fugly
|
|
* p = MakeUnique<char>(); // preferred
|
|
*
|
|
* (And third, although not relevant to Mozilla: MakeUnique is exception-safe.
|
|
* An exception thrown after |new T| succeeds will leak that memory, unless the
|
|
* pointer is assigned to an object that will manage its ownership. UniquePtr
|
|
* ably serves this function.)
|
|
*/
|
|
|
|
// We don't have variadic template support everywhere, so just hard-code arities
|
|
// 0-8 for now. If you need more arguments, feel free to add the extra
|
|
// overloads (and deletions for the T = E[N] case).
|
|
//
|
|
// Beware! Due to lack of true nullptr support in gcc 4.4 and 4.5, passing
|
|
// literal nullptr to MakeUnique will not work on some platforms. See Move.h
|
|
// for more details.
|
|
|
|
template<typename T>
|
|
typename detail::UniqueSelector<T>::SingleObject
|
|
MakeUnique()
|
|
{
|
|
return UniquePtr<T>(new T());
|
|
}
|
|
|
|
template<typename T, typename A1>
|
|
typename detail::UniqueSelector<T>::SingleObject
|
|
MakeUnique(A1&& aA1)
|
|
{
|
|
return UniquePtr<T>(new T(Forward<A1>(aA1)));
|
|
}
|
|
|
|
template<typename T, typename A1, typename A2>
|
|
typename detail::UniqueSelector<T>::SingleObject
|
|
MakeUnique(A1&& aA1, A2&& aA2)
|
|
{
|
|
return UniquePtr<T>(new T(Forward<A1>(aA1), Forward<A2>(aA2)));
|
|
}
|
|
|
|
template<typename T, typename A1, typename A2, typename A3>
|
|
typename detail::UniqueSelector<T>::SingleObject
|
|
MakeUnique(A1&& aA1, A2&& aA2, A3&& aA3)
|
|
{
|
|
return UniquePtr<T>(new T(Forward<A1>(aA1), Forward<A2>(aA2),
|
|
Forward<A3>(aA3)));
|
|
}
|
|
|
|
template<typename T, typename A1, typename A2, typename A3, typename A4>
|
|
typename detail::UniqueSelector<T>::SingleObject
|
|
MakeUnique(A1&& aA1, A2&& aA2, A3&& aA3, A4&& aA4)
|
|
{
|
|
return UniquePtr<T>(new T(Forward<A1>(aA1), Forward<A2>(aA2),
|
|
Forward<A3>(aA3), Forward<A4>(aA4)));
|
|
}
|
|
|
|
template<typename T, typename A1, typename A2, typename A3, typename A4,
|
|
typename A5>
|
|
typename detail::UniqueSelector<T>::SingleObject
|
|
MakeUnique(A1&& aA1, A2&& aA2, A3&& aA3, A4&& aA4, A5&& aA5)
|
|
{
|
|
return UniquePtr<T>(new T(Forward<A1>(aA1), Forward<A2>(aA2),
|
|
Forward<A3>(aA3), Forward<A4>(aA4),
|
|
Forward<A5>(aA5)));
|
|
}
|
|
|
|
template<typename T, typename A1, typename A2, typename A3, typename A4,
|
|
typename A5, typename A6>
|
|
typename detail::UniqueSelector<T>::SingleObject
|
|
MakeUnique(A1&& a1, A2&& a2, A3&& a3, A4&& a4, A5&& a5, A6&& a6)
|
|
{
|
|
return UniquePtr<T>(new T(Forward<A1>(a1), Forward<A2>(a2),
|
|
Forward<A3>(a3), Forward<A4>(a4),
|
|
Forward<A5>(a5), Forward<A6>(a6)));
|
|
}
|
|
|
|
template<typename T, typename A1, typename A2, typename A3, typename A4,
|
|
typename A5, typename A6, typename A7>
|
|
typename detail::UniqueSelector<T>::SingleObject
|
|
MakeUnique(A1&& a1, A2&& a2, A3&& a3, A4&& a4, A5&& a5, A6&& a6, A7&& a7)
|
|
{
|
|
return UniquePtr<T>(new T(Forward<A1>(a1), Forward<A2>(a2),
|
|
Forward<A3>(a3), Forward<A4>(a4),
|
|
Forward<A5>(a5), Forward<A6>(a6),
|
|
Forward<A7>(a7)));
|
|
}
|
|
|
|
template<typename T, typename A1, typename A2, typename A3, typename A4,
|
|
typename A5, typename A6, typename A7, typename A8>
|
|
typename detail::UniqueSelector<T>::SingleObject
|
|
MakeUnique(A1&& a1, A2&& a2, A3&& a3, A4&& a4, A5&& a5, A6&& a6, A7&& a7,
|
|
A8&& a8)
|
|
{
|
|
return UniquePtr<T>(new T(Forward<A1>(a1), Forward<A2>(a2),
|
|
Forward<A3>(a3), Forward<A4>(a4),
|
|
Forward<A5>(a5), Forward<A6>(a6),
|
|
Forward<A7>(a7), Forward<A8>(a8)));
|
|
}
|
|
|
|
template<typename T>
|
|
typename detail::UniqueSelector<T>::UnknownBound
|
|
MakeUnique(decltype(sizeof(int)) aN)
|
|
{
|
|
typedef typename RemoveExtent<T>::Type ArrayType;
|
|
return UniquePtr<T>(new ArrayType[aN]());
|
|
}
|
|
|
|
template<typename T>
|
|
typename detail::UniqueSelector<T>::KnownBound
|
|
MakeUnique() MOZ_DELETE;
|
|
|
|
template<typename T, typename A1>
|
|
typename detail::UniqueSelector<T>::KnownBound
|
|
MakeUnique(A1&& aA1) MOZ_DELETE;
|
|
|
|
template<typename T, typename A1, typename A2>
|
|
typename detail::UniqueSelector<T>::KnownBound
|
|
MakeUnique(A1&& aA1, A2&& aA2) MOZ_DELETE;
|
|
|
|
template<typename T, typename A1, typename A2, typename A3>
|
|
typename detail::UniqueSelector<T>::KnownBound
|
|
MakeUnique(A1&& aA1, A2&& aA2, A3&& aA3) MOZ_DELETE;
|
|
|
|
template<typename T, typename A1, typename A2, typename A3, typename A4>
|
|
typename detail::UniqueSelector<T>::KnownBound
|
|
MakeUnique(A1&& aA1, A2&& aA2, A3&& aA3, A4&& aA4) MOZ_DELETE;
|
|
|
|
template<typename T, typename A1, typename A2, typename A3, typename A4,
|
|
typename A5>
|
|
typename detail::UniqueSelector<T>::KnownBound
|
|
MakeUnique(A1&& aA1, A2&& aA2, A3&& aA3, A4&& aA4, A5&& aA5) MOZ_DELETE;
|
|
|
|
template<typename T, typename A1, typename A2, typename A3, typename A4,
|
|
typename A5, typename A6>
|
|
typename detail::UniqueSelector<T>::KnownBound
|
|
MakeUnique(A1&& a1, A2&& a2, A3&& a3, A4&& a4, A5&& a5,
|
|
A6&& a6) MOZ_DELETE;
|
|
|
|
template<typename T, typename A1, typename A2, typename A3, typename A4,
|
|
typename A5, typename A6, typename A7>
|
|
typename detail::UniqueSelector<T>::KnownBound
|
|
MakeUnique(A1&& a1, A2&& a2, A3&& a3, A4&& a4, A5&& a5, A6&& a6,
|
|
A7&& a7) MOZ_DELETE;
|
|
|
|
template<typename T, typename A1, typename A2, typename A3, typename A4,
|
|
typename A5, typename A6, typename A7, typename A8>
|
|
typename detail::UniqueSelector<T>::KnownBound
|
|
MakeUnique(A1&& a1, A2&& a2, A3&& a3, A4&& a4, A5&& a5, A6&& a6,
|
|
A7&& a7, A8&& a8) MOZ_DELETE;
|
|
|
|
} // namespace mozilla
|
|
|
|
#endif /* mozilla_UniquePtr_h */
|