mbed-os/platform/cxxsupport/mstd_memory

/* mbed Microcontroller Library
 * Copyright (c) 2019 ARM Limited
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#ifndef MSTD_MEMORY_
#define MSTD_MEMORY_

/* <mstd_memory>
 *
 * - includes toolchain's <memory>
 * - For ARM C 5, C++11/14 features:
 *   - std::align
 *   - std::addressof
 */

#include <memory>

#ifdef __CC_ARM

#include <cstddef> // size_t, ptrdiff_t

namespace std
{
// [ptr.align]
inline void *align(size_t alignment, size_t size, void *&ptr, size_t &space) noexcept
{
    /* Behavior is undefined if alignment is not a power of 2 */
    uintptr_t addr = reinterpret_cast<uintptr_t>(ptr);
    uintptr_t new_addr = (addr + (alignment - 1)) & ~(alignment - 1);
    uintptr_t pad = new_addr - addr;
    if (pad + size <= space) {
        space -= pad;
        ptr = reinterpret_cast<void *>(new_addr);
        return ptr;
    } else {
        return nullptr;
    }
}

// [specialized.addressof]
template <typename T>
T *addressof(T &arg) noexcept
{
    return reinterpret_cast<T *>(const_cast<char *>(&reinterpret_cast<const volatile char &>(arg)));
}

} // namespace std

#endif // __CC_ARM

namespace mstd {
    using std::allocator;
    using std::uninitialized_copy;
    using std::uninitialized_fill;
    using std::uninitialized_fill_n;
    using std::addressof;
    using std::align;
}

#endif // MSTD_MEMORY_