base/scope_guard.hpp


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/// @author	Yury Melnichek mailto:melnichek@gmail.com
/// @date	07.01.2005
/// @brief	See http://gzip.rsdn.ru/forum/Message.aspx?mid=389127&only=1.

#pragma once

#include "base/base.hpp"

namespace base
{
namespace impl
{
  /// Base class for all ScopeGuards.
  class GuardBase
  {
  public:
    /// Disable ScopeGuard functionality on it's destruction
    void release() const
    {
      m_bDoRollback = false;
    }

  protected:

    GuardBase() : m_bDoRollback(true)
    {
    }

    // Do something in the destructor
    mutable bool m_bDoRollback;
  };

  /// ScopeGuard for specific functor
  template <typename TFunctor> class GuardImpl : public GuardBase
  {
  public:
    explicit GuardImpl(TFunctor const & F) : m_Functor(F)
    {
    }

    ~GuardImpl()
    {
      if (m_bDoRollback)
        m_Functor();
    }

  private:
    TFunctor m_Functor;
  };
} // namespace impl

typedef impl::GuardBase const & scope_guard;

/// Create scope_guard
template <typename TFunctor>
impl::GuardImpl<TFunctor> make_scope_guard(TFunctor const & F)
{
  return impl::GuardImpl<TFunctor>(F);
}
} // namespace base

#define SCOPE_GUARD(name, func)                            \
  ::base::scope_guard name = base::make_scope_guard(func); \
  static_cast<void>(name);