| // Copyright 2017 The Fuchsia 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 FBL_ALLOC_CHECKER_H_ |
| #define FBL_ALLOC_CHECKER_H_ |
| |
| #include <memory> |
| #include <new> |
| #include <utility> |
| #include <stddef.h> |
| #include <zircon/assert.h> |
| |
| namespace fbl { |
| |
| // An object which is passed to operator new to allow client code to handle |
| // allocation failures. Once armed by operator new, the client must call `check()` |
| // to verify the state of the allocation checker before it goes out of scope. |
| // |
| // Use it like this: |
| // |
| // AllocChecker ac; |
| // MyObject* obj = new (&ac) MyObject(); |
| // if (!ac.check()) { |
| // // handle allocation failure (obj will be null) |
| // } |
| class AllocChecker { |
| public: |
| AllocChecker(); |
| ~AllocChecker(); |
| void arm(size_t size, bool result); |
| bool check(); |
| |
| private: |
| unsigned state_; |
| }; |
| |
| namespace internal { |
| |
| template <typename T> |
| struct unique_type { |
| using single = std::unique_ptr<T>; |
| }; |
| |
| template <typename T> |
| struct unique_type<T[]> { |
| using incomplete_array = std::unique_ptr<T[]>; |
| }; |
| |
| } // namespace internal |
| |
| template <typename T, typename... Args> |
| typename internal::unique_type<T>::single make_unique_checked(AllocChecker* ac, Args&&... args) { |
| return std::unique_ptr<T>(new (ac) T(std::forward<Args>(args)...)); |
| } |
| |
| } // namespace fbl |
| |
| void* operator new(size_t size, std::align_val_t align, fbl::AllocChecker* ac) noexcept; |
| void* operator new[](size_t size, std::align_val_t align, fbl::AllocChecker* ac) noexcept; |
| |
| void* operator new(size_t size, fbl::AllocChecker* ac) noexcept; |
| void* operator new[](size_t size, fbl::AllocChecker* ac) noexcept; |
| |
| #endif // FBL_ALLOC_CHECKER_H_ |