fallback_allocator.h

// Copyright 2023 The Pigweed Authors
//
// 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
//
//     https://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.
#pragma once
 
#include <cstddef>
 
#include "pw_allocator/allocator.h"
#include "pw_allocator/layout.h"
#include "pw_result/result.h"
#include "pw_status/status.h"
 
namespace pw::allocator {
 
 
class FallbackAllocator : public pw::Allocator {
 public:
  FallbackAllocator(pw::Allocator& primary, pw::Allocator& secondary);
 
 private:
  void* DoAllocate(Layout layout) override;
 
  void DoDeallocate(void* ptr) override;
 
  bool DoResize(void* ptr, size_t new_size) override;
 
  size_t DoGetAllocated() const override;
 
  Result<Layout> DoGetInfo(InfoType info_type, const void* ptr) const override;
 
 protected:
  std::optional<allocator::Fragmentation> DoMeasureFragmentation()
      const override {
    return primary_.MeasureFragmentation();
  }
 
 private:
  pw::Allocator& primary_;
  pw::Allocator& secondary_;
};
 
 
}  // namespace pw::allocator