aligned_buf.h

/*
 * Copyright 2013 Google Inc.
 *
 * 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.
 */
 
// A convenient wrapper for buffers with alignment constraints
 
// Note that if we were on C++11, we'd use aligned_storage or somesuch.
 
#pragma once
 
#include <stddef.h>
 
template <typename T, size_t size, size_t alignment = 16>
class AlignedBuf {
public:
    T* get() { return (T*)((((intptr_t)storage_) + alignment - 1) & -alignment); }
 
private:
    unsigned char storage_[size * sizeof(T) + alignment];
};