text: //  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
  //  This source code is licensed under the BSD-style license found in the
  //  LICENSE file in the root directory of this source tree. An additional grant
  //  of patent rights can be found in the PATENTS file in the same directory.
  //
  // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file. See the AUTHORS file for names of contributors.
  //
  // This is used by the MemTable to allocate write buffer memory. It connects
  // to WriteBuffer so we can track and enforce overall write buffer limits.
  
  #pragma once
  
  #include <atomic>
  #include "util/allocator.h"
  
  namespace vidardb {
  
  class Logger;
  class WriteBuffer;
  
  class MemTableAllocator : public Allocator {
   public:
    explicit MemTableAllocator(Allocator* allocator, WriteBuffer* write_buffer);
    ~MemTableAllocator();
  
    // Allocator interface
    char* Allocate(size_t bytes) override;
    char* AllocateAligned(size_t bytes, size_t huge_page_size = 0,
                          Logger* logger = nullptr) override;
    size_t BlockSize() const override;
  
    // Call when we're finished allocating memory so we can free it from
    // the write buffer's limit.
    void DoneAllocating();
  
   private:
    Allocator* allocator_;
    WriteBuffer* write_buffer_;
    std::atomic<size_t> bytes_allocated_;
  
    // No copying allowed
    MemTableAllocator(const MemTableAllocator&);
    void operator=(const MemTableAllocator&);
  };
  
  }  // namespace vidardb
  