lasp/cpp_src/device/lasp_indatahandler.h

#pragma once
#include "lasp_types.h"
#include <atomic>
#include <functional>
#include <memory>
#include <thread>

class StreamMgr;
using SmgrHandle = std::shared_ptr<StreamMgr>;

class DaqData;
class Daq;

/** \addtogroup device
 * @{
 */

/**
 * @brief The function definition of callbacks with incoming DAQ data
 */
using InCallbackType = std::function<void(const DaqData &)>;
/**
 * @brief Function definition for the reset callback.
 */
using ResetCallbackType = std::function<void(const Daq *)>;

class InDataHandler {

protected:
  std::weak_ptr<StreamMgr> _mgr;
#if LASP_DEBUG == 1
  // This is a flag to indicate whether the method stop() is called for the
  // current handler. It should call the method stop() from the derived class's
  // destructor.
  std::atomic<bool> stopCalled{false};
#endif

public:
  ~InDataHandler();
  const InCallbackType inCallback;
  const ResetCallbackType reset;

  /**
   * @brief When constructed, the handler is added to the stream manager, which
   * will call the handlers's inCallback() until stop() is called.
   *
   * @param mgr Stream manager.
   * @param cb The callback that is stored, and called on new DAQ data
   * @param resetfcn The callback that is stored, and called when the DAQ
   * changes state.
   */
  InDataHandler(SmgrHandle mgr, InCallbackType cb,
                ResetCallbackType resetfcn);

  /**
   * @brief Adds the current InDataHandler to the list of handlers in the
   * StreamMgr. After this happens, the reset() method stored in this
   * object is called back. When the stream is running, right after this,
   * inCallback() is called with DaqData.
   */
  void start();

  /**
   * @brief Removes the currend InDataHandler from the list of handlers in the
   * StreamMgr. From that point on, the object can be safely destroyed. Not
   * calling stop() before destruction of this object is considered a BUG. I.e.
   * a class which *uses* an InDataHandler should always call stop() in its
   * destructor.
   */
  void stop();

#if LASP_DEBUG == 1
  const std::thread::id main_thread_id;
  void checkRightThread() const;
#else
  void checkRightThread() const {}
#endif
};
/** @} */