LockableReference.hpp

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#ifndef DART_COMMON_LOCKABLEREFERENCE_HPP_
#define DART_COMMON_LOCKABLEREFERENCE_HPP_

#include <memory>
#include <vector>

namespace dart {
namespace common {

class LockableReference
{
public:
  constexpr LockableReference() noexcept = default;

  virtual ~LockableReference() = default;

  virtual void lock() = 0;

  virtual bool try_lock() noexcept = 0;

  virtual void unlock() noexcept = 0;

protected:
  LockableReference(const LockableReference&) = delete;
};

template <typename LockableT>
class SingleLockableReference final : public LockableReference
{
public:
  using Lockable = LockableT;

  SingleLockableReference(
      std::weak_ptr<const void> lockableHolder, Lockable& lockable) noexcept;

  // Documentation inherited
  void lock() override;

  // Documentation inherited
  bool try_lock() noexcept override;

  // Documentation inherited
  void unlock() noexcept override;

private:
  std::weak_ptr<const void> mLockableHolder;

  Lockable& mLockable;
};

template <typename LockableT>
class MultiLockableReference final : public LockableReference
{
public:
  using Lockable = LockableT;

  template <typename InputIterator>
  MultiLockableReference(
      std::weak_ptr<const void> lockableHolder,
      InputIterator first,
      InputIterator last);

  // Documentation inherited
  void lock() override;

  // Documentation inherited
  bool try_lock() noexcept override;

  // Documentation inherited
  void unlock() noexcept override;

private:
  template <typename T>
  T* ptr(T& obj);

  template <typename T>
  T* ptr(T* obj);

  std::weak_ptr<const void> mLockableHolder;

  std::vector<Lockable*> mLockables;
};

} // namespace common
} // namespace dart

#include "dart/common/detail/LockableReference-impl.hpp"

#endif // DART_COMMON_LOCKABLEREFERENCE_HPP_