Moved IndataHandler to its own implementation file. Refactored some code. Fixed race conditions when starting and stopping indatahandlers. It appears that this does not solve the segfault, but is at least mitigates some race conditions when constructors are not ready on an object, and avoiding the call of virtual functions of an object which destructor has already been called. Added some extra assert check that a function is called from the right thread. Put explicit start and stop methods in constructor / destructor of PyInDataHandler. WARNING: this means all .start() and .stop() methods should be removed. THIS IS AN API break!

src/lasp/device/CMakeLists.txt

@@ -7,6 +7,7 @@ add_library(lasp_device_lib OBJECT
     lasp_deviceinfo.cpp
     lasp_rtaudiodaq.cpp
     lasp_streammgr.cpp
+    lasp_indatahandler.cpp
     lasp_uldaq.cpp
     lasp_uldaq_impl.cpp
     )

src/lasp/device/lasp_daq.h

@@ -5,6 +5,8 @@
 #include "lasp_types.h"
 #include <functional>
 #include <memory>
+#include <mutex>
+#include <atomic>
 
 /**
  * \defgroup device Device interfacing

src/lasp/device/lasp_deviceinfo.h

@@ -19,6 +19,7 @@ public:
    * @brief Virtual desctructor. Can be derived class.
    */
   virtual ~DeviceInfo() {}
+  DeviceInfo& operator=(const DeviceInfo&) = delete;
 
   /**
    * @brief Clone a device info.

src/lasp/device/lasp_indatahandler.cpp

@@ -0,0 +1,39 @@
+/* #define DEBUGTRACE_ENABLED */
+#include <thread>
+#include "debugtrace.hpp"
+#include "lasp_indatahandler.h"
+#include "lasp_streammgr.h"
+
+InDataHandler::InDataHandler(StreamMgr &mgr) : _mgr(mgr)
+#if LASP_DEBUG==1
+ , _main_thread_id(std::this_thread::get_id())
+#endif
+{ DEBUGTRACE_ENTER; }
+void InDataHandler::start() {
+  DEBUGTRACE_ENTER;
+  _mgr.addInDataHandler(*this);
+
+#if LASP_DEBUG == 1
+  assert(_mgr._main_thread_id == _main_thread_id);
+#endif
+}
+void InDataHandler::stop() {
+#if LASP_DEBUG == 1
+  stopCalled = true;
+#endif
+  _mgr.removeInDataHandler(*this);
+}
+
+InDataHandler::~InDataHandler() {
+
+  DEBUGTRACE_ENTER;
+#if LASP_DEBUG == 1
+  if (!stopCalled) {
+    std::cerr << "************ BUG: Stop function not called while arriving at "
+            "InDataHandler's destructor. Fix this by calling "
+            "InDataHandler::stop() from the derived class' destructor."
+         << std::endl;
+    abort();
+  }
+#endif
+}

src/lasp/device/lasp_indatahandler.h

@@ -0,0 +1,76 @@
+#pragma once
+#include <atomic>
+#include <thread>
+#include "lasp_types.h"
+
+/** \addtogroup device
+ * @{
+ */
+class StreamMgr;
+class DaqData;
+class Daq;
+class InDataHandler {
+
+protected:
+  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:
+  virtual ~InDataHandler();
+
+  /**
+   * @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.
+   */
+  InDataHandler(StreamMgr &mgr);
+
+  /**
+   * @brief This function is called when input data from a DAQ is available.
+   *
+   * @param daqdata Input data from DAQ
+   *
+   * @return true if no error. False to stop the stream from running.
+   */
+  virtual bool inCallback(const DaqData &daqdata) = 0;
+
+  /**
+   * @brief Reset in-data handler.
+   *
+   * @param daq New DAQ configuration of inCallback(). If nullptr is given,
+   * it means that the stream is stopped.
+   */
+  virtual void reset(const Daq *daq = nullptr) = 0;
+
+  /**
+   * @brief This function should be called from the constructor of the
+   * implementation of InDataHandler, that one than also implements
+   * `inCallback`. It will start the stream's calling of inCallback().
+   */
+  void start();
+
+  /**
+   * @brief This function should be called from the destructor of derived
+   * classes, to disable the calls to inCallback(), such that proper
+   * destruction of the object is allowed and no other threads call methods
+   * from the object. It removes the inCallback() from the callback list of the
+   * StreamMgr(). **Failing to call this function results in deadlocks, errors
+   * like "pure virtual function called", or other**.
+   */
+  void stop();
+
+private:
+#if LASP_DEBUG == 1
+  const std::thread::id _main_thread_id;
+  void checkRightThread() const;
+#else
+  void checkRightThread() const {}
+#endif
+};
+/** @} */

src/lasp/device/lasp_streammgr.cpp

@@ -1,8 +1,9 @@
 /* #define DEBUGTRACE_ENABLED */
-#include "lasp_streammgr.h"
 #include "debugtrace.hpp"
+#include "lasp_streammgr.h"
 #include "lasp_biquadbank.h"
 #include "lasp_thread.h"
+#include "lasp_indatahandler.h"
 #include <algorithm>
 #include <assert.h>
 #include <functional>
@@ -12,30 +13,6 @@ using std::cerr;
 using std::endl;
 using rte = std::runtime_error;
 
-InDataHandler::InDataHandler(StreamMgr &mgr) : _mgr(mgr) { DEBUGTRACE_ENTER; }
-void InDataHandler::start() {
-  DEBUGTRACE_ENTER;
-  _mgr.addInDataHandler(*this);
-}
-void InDataHandler::stop() {
-#if LASP_DEBUG == 1
-  stopCalled = true;
-#endif
-  _mgr.removeInDataHandler(*this);
-}
-InDataHandler::~InDataHandler() {
-
-  DEBUGTRACE_ENTER;
-#if LASP_DEBUG == 1
-  if (!stopCalled) {
-    cerr << "************ BUG: Stop function not called while arriving at "
-            "InDataHandler's destructor. Fix this by calling "
-            "InDataHandler::stop() from the derived class' destructor."
-         << endl;
-    abort();
-  }
-#endif
-}
 
 StreamMgr &StreamMgr::getInstance() {
 
@@ -43,6 +20,7 @@ StreamMgr &StreamMgr::getInstance() {
   static StreamMgr mgr;
   return mgr;
 }
+
 StreamMgr::StreamMgr() {
   DEBUGTRACE_ENTER;
 #if LASP_DEBUG == 1
@@ -63,16 +41,16 @@ void StreamMgr::rescanDAQDevices(bool background,
   auto &pool = getPool();
 
   checkRightThread();
+  if (_inputStream || _outputStream) {
+    throw rte("Rescanning DAQ devices only possible when no stream is running");
+  }
   if (!_devices_mtx.try_lock()) {
     throw rte("A background DAQ device scan is probably already running");
   }
   _devices_mtx.unlock();
 
-  if (_inputStream || _outputStream) {
+  std::scoped_lock lck(_devices_mtx);
-    throw rte("Rescanning DAQ devices only possible when no stream is running");
-  }
   _devices.clear();
-  /* auto &pool = getPool(); */
   if (!background) {
     rescanDAQDevices_impl(callback);
   } else {

src/lasp/device/lasp_streammgr.h

@@ -10,60 +10,8 @@
  * @{
  */
 class StreamMgr;
+class InDataHandler;
 
-class InDataHandler {
-
-protected:
-  StreamMgr &_mgr;
-#if LASP_DEBUG == 1
-  std::atomic<bool> stopCalled{false};
-#endif
-
-public:
-  virtual ~InDataHandler();
-
-  /**
-   * @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.
-   */
-  InDataHandler(StreamMgr &mgr);
-
-  /**
-   * @brief This function is called when input data from a DAQ is available.
-   *
-   * @param daqdata Input data from DAQ
-   *
-   * @return true if no error. False to stop the stream from running.
-   */
-  virtual bool inCallback(const DaqData &daqdata) = 0;
-
-  /**
-   * @brief Reset in-data handler.
-   *
-   * @param daq New DAQ configuration of inCallback(). If nullptr is given,
-   * it means that the stream is stopped.
-   */
-  virtual void reset(const Daq *daq = nullptr) = 0;
-
-  /**
-   * @brief This function should be called from the constructor of the
-   * implementation of InDataHandler. It will start the stream's calling of
-   * inCallback().
-   */
-  void start();
-
-  /**
-   * @brief This function should be called from the destructor of derived
-   * classes, to disable the calls to inCallback(), such that proper
-   * destruction of the object is allowed and no other threads call methods
-   * from the object. It removes the inCallback() from the callback list of the
-   * StreamMgr(). **Failing to call this function results in deadlocks, errors
-   * like "pure virtual function called", or other**.
-   */
-  void stop();
-};
 
 class SeriesBiquad;
 
@@ -76,9 +24,6 @@ class SeriesBiquad;
  * fact is asserted.
  */
 class StreamMgr {
-#if LASP_DEBUG == 1
-  std::thread::id _main_thread_id;
-#endif
 
   /**
    * @brief Storage for streams.
@@ -91,22 +36,25 @@ class StreamMgr {
    * thread-safety.
    */
   std::list<InDataHandler *> _inDataHandlers;
-  std::mutex _inDataHandler_mtx;
+  mutable std::mutex _inDataHandler_mtx;
 
   /**
    * @brief Signal generator in use to generate output data. Currently
    * implemented as to generate the same data for all output channels.
    */
   std::shared_ptr<Siggen> _siggen;
+  std::mutex _siggen_mtx;
 
   /**
    * @brief Filters on input stream. For example, a digital high pass filter.
    */
   std::vector<std::unique_ptr<SeriesBiquad>> _inputFilters;
 
-  std::mutex _siggen_mtx;
 
-  std::mutex _devices_mtx;
+  mutable std::recursive_mutex _devices_mtx;
+  /**
+   * @brief Current storage for the device list
+   */
   DeviceInfoList _devices;
 
   StreamMgr();
@@ -146,7 +94,7 @@ class StreamMgr {
    * @return A copy of the internal stored list of devices
    */
   DeviceInfoList getDeviceInfo() const {
-    std::scoped_lock lck(const_cast<std::mutex &>(_devices_mtx));
+  std::scoped_lock lck(_devices_mtx);
     DeviceInfoList d2;
     for(const auto& dev: _devices) {
       d2.push_back(dev->clone());
@@ -157,7 +105,8 @@ class StreamMgr {
   /**
    * @brief Triggers a background scan of the DAQ devices, which updates the
    * internally stored list of devices. Throws a runtime error when a
-   * background thread is already scanning for devices.
+   * background thread is already scanning for devices, or if a stream is
+   * running.
    *
    * @param background Perform searching for DAQ devices in the background. If
    * set to true, the function returns immediately.
@@ -261,6 +210,7 @@ private:
   void rescanDAQDevices_impl(std::function<void()> callback);
 
 #if LASP_DEBUG == 1
+  std::thread::id _main_thread_id;
   void checkRightThread() const;
 #else
   void checkRightThread() const {}

src/lasp/dsp/lasp_clip.cpp

@@ -1,6 +1,8 @@
 /* #define DEBUGTRACE_ENABLED */
 #include "debugtrace.hpp"
 #include "lasp_clip.h"
+#include "lasp_daqdata.h"
+#include "lasp_daq.h"
 #include <mutex>
 
 using std::cerr;
@@ -13,6 +15,7 @@ ClipHandler::ClipHandler(StreamMgr &mgr)
   : ThreadedInDataHandler(mgr){
 
     DEBUGTRACE_ENTER;
+    startThread();
   }
 
 bool ClipHandler::inCallback_threaded(const DaqData &d) {
@@ -89,6 +92,5 @@ void ClipHandler::reset(const Daq *daq) {
 
 ClipHandler::~ClipHandler() {
   DEBUGTRACE_ENTER;
-  Lck lck(_mtx);
+  stopThread();
-  stop();
 }

src/lasp/dsp/lasp_ppm.cpp

@@ -1,6 +1,8 @@
 /* #define DEBUGTRACE_ENABLED */
 #include "debugtrace.hpp"
 #include "lasp_ppm.h"
+#include "lasp_daqdata.h"
+#include "lasp_daq.h"
 #include <mutex>
 
 using std::cerr;
@@ -13,6 +15,7 @@ PPMHandler::PPMHandler(StreamMgr &mgr, const d decay_dBps)
   : ThreadedInDataHandler(mgr), _decay_dBps(decay_dBps) {
 
     DEBUGTRACE_ENTER;
+    startThread();
   }
 
 bool PPMHandler::inCallback_threaded(const DaqData &d) {
@@ -106,6 +109,5 @@ void PPMHandler::reset(const Daq *daq) {
 
 PPMHandler::~PPMHandler() {
   DEBUGTRACE_ENTER;
-  Lck lck(_mtx);
+  stopThread();
-  stop();
 }

src/lasp/dsp/lasp_rtaps.cpp

@@ -1,5 +1,7 @@
 /* #define DEBUGTRACE_ENABLED */
 #include "lasp_rtaps.h"
+#include "lasp_daqdata.h"
+#include "lasp_daq.h"
 #include "debugtrace.hpp"
 #include <mutex>
 
@@ -18,10 +20,10 @@ RtAps::RtAps(StreamMgr &mgr, const Filter *freqWeightingFilter,
       _filterPrototype = freqWeightingFilter->clone();
     }
 
+    startThread();
   }
 RtAps::~RtAps() {
-  Lck lck(_ps_mtx);
+  stopThread();
-  stop();
 }
 bool RtAps::inCallback_threaded(const DaqData &data) {
 

src/lasp/dsp/lasp_rtsignalviewer.cpp

@@ -1,5 +1,7 @@
 /* #define DEBUGTRACE_ENABLED */
 #include "debugtrace.hpp"
+#include "lasp_daqdata.h"
+#include "lasp_daq.h"
 #include "lasp_rtsignalviewer.h"
 #include <algorithm>
 #include <mutex>
@@ -22,6 +24,7 @@ RtSignalViewer::RtSignalViewer(StreamMgr &mgr, const d approx_time_hist,
     if (resolution <= 1) {
       throw rte("Invalid resolution. Should be > 1");
     }
+    startThread();
   }
 
 bool RtSignalViewer::inCallback_threaded(const DaqData &data) {
@@ -54,8 +57,7 @@ bool RtSignalViewer::inCallback_threaded(const DaqData &data) {
 }
 
 RtSignalViewer::~RtSignalViewer() {
-  Lck lck(_sv_mtx);
+  stopThread();
-  stop();
 }
 void RtSignalViewer::reset(const Daq *daq) {
 

src/lasp/dsp/lasp_threadedindatahandler.cpp

@@ -1,11 +1,12 @@
 /* #define DEBUGTRACE_ENABLED */
 #include "lasp_threadedindatahandler.h"
 #include "debugtrace.hpp"
+#include "lasp_daqdata.h"
 #include "lasp_thread.h"
 #include <future>
-#include <thread>
-#include <queue>
 #include <optional>
+#include <queue>
+#include <thread>
 
 using namespace std::literals::chrono_literals;
 using lck = std::scoped_lock<std::mutex>;
@@ -16,9 +17,10 @@ using std::endl;
 class SafeQueue {
   std::queue<DaqData> _queue;
   std::mutex _mtx;
-  std::atomic_int32_t _contents {0};
+  std::atomic_int32_t _contents{0};
-  public:
+
-  void push(const DaqData& d) {
+public:
+  void push(const DaqData &d) {
     DEBUGTRACE_ENTER;
     lck lock(_mtx);
     _queue.push(d);
@@ -54,18 +56,26 @@ ThreadedInDataHandler::ThreadedInDataHandler(StreamMgr &mgr)
 
   // Initialize thread pool, if not already done
   getPool();
-  }
+}
+void ThreadedInDataHandler::startThread() {
+  _thread_can_safely_run = true;
+  start();
+}
 
 bool ThreadedInDataHandler::inCallback(const DaqData &daqdata) {
   DEBUGTRACE_ENTER;
+  std::scoped_lock lck(_mtx);
+
+  // Early return in case object is under DESTRUCTION
+  if (!_thread_can_safely_run)
+    return true;
 
   if (!_lastCallbackResult) {
     return false;
   }
 
   _queue->push(daqdata);
-
+  if (!_thread_running && _lastCallbackResult) {
-  if (!_thread_running && (!_stopThread) && _lastCallbackResult) {
     auto &pool = getPool();
     DEBUGTRACE_PRINT("Pushing new thread in pool");
     _thread_running = true;
@@ -74,11 +84,13 @@ bool ThreadedInDataHandler::inCallback(const DaqData &daqdata) {
 
   return _lastCallbackResult;
 }
+void ThreadedInDataHandler::stopThread() {
 
-ThreadedInDataHandler::~ThreadedInDataHandler() {
+  // Make sure inCallback is no longer called
+  _thread_can_safely_run = false;
+  stop();
 
-  DEBUGTRACE_ENTER;
+  std::scoped_lock lck(_mtx);
-  _stopThread = true;
 
   // Then wait in steps for the thread to stop running.
   while (_thread_running) {
@@ -86,11 +98,23 @@ ThreadedInDataHandler::~ThreadedInDataHandler() {
   }
 }
 
+ThreadedInDataHandler::~ThreadedInDataHandler() {
+
+  DEBUGTRACE_ENTER;
+  if (_thread_can_safely_run) {
+    stopThread();
+    cerr << "*** BUG: InDataHandlers have not been all stopped, while "
+            "StreamMgr destructor is called. This is a misuse BUG."
+         << endl;
+    abort();
+  }
+}
+
 void ThreadedInDataHandler::threadFcn() {
 
   DEBUGTRACE_ENTER;
 
-  while(!_queue->empty() && !_stopThread) {
+  while (!_queue->empty() && _thread_can_safely_run) {
 
     // Call inCallback_threaded
     if (!inCallback_threaded(_queue->pop())) {

src/lasp/dsp/lasp_threadedindatahandler.h

@@ -1,9 +1,11 @@
 #pragma once
-#include "lasp_streammgr.h"
+#include "lasp_indatahandler.h"
+#include <atomic>
+#include <memory>
+#include <mutex>
 
 const us RINGBUFFER_SIZE = 1024;
 
-
 /**
  * \addtogroup dsp
  * @{
@@ -17,25 +19,40 @@ class SafeQueue;
  * @brief Threaded in data handler. Buffers inCallback data and calls a
  * callback with the same signature on a different thread.
  */
-class ThreadedInDataHandler: public InDataHandler {
+class ThreadedInDataHandler : protected InDataHandler {
   /**
    * @brief The queue used to push elements to the handling thread.
    */
   std::unique_ptr<SafeQueue> _queue;
+  mutable std::recursive_mutex _mtx;
 
   std::atomic<bool> _thread_running{false};
-  std::atomic<bool> _stopThread{false};
   std::atomic<bool> _lastCallbackResult{true};
+  std::atomic<bool> _thread_can_safely_run{false};
 
   void threadFcn();
 
-  public:
+protected:
+  /**
+   * @brief This method should be called from the derived class' constructor,
+   * to start the thread and data is incoming.
+   */
+  void startThread();
+  /**
+   * @brief This method SHOULD be called from all classes that derive on
+   * ThreadedInDataHandler. It is to make sure the inCallback_threaded()
+   * function is no longer called when the destructor of the derived class is
+   * called. Not calling this function is regarded as a BUG.
+   */
+  void stopThread();
+
+public:
   /**
    * @brief Initialize a ThreadedInDataHandler
    *
    * @param mgr StreamMgr singleton reference
    */
-  ThreadedInDataHandler(StreamMgr& mgr);
+  ThreadedInDataHandler(StreamMgr &mgr);
   ~ThreadedInDataHandler();
 
   /**
@@ -55,10 +72,8 @@ class ThreadedInDataHandler: public InDataHandler {
    *
    * @return true on succes. False when an error occured.
    */
-  virtual bool inCallback_threaded(const DaqData& d) = 0;
+  virtual bool inCallback_threaded(const DaqData &d) = 0;
-
 };
 
-
 /** @} */
 /** @} */

src/lasp/lasp_record.py

@@ -19,7 +19,9 @@ class RecordStatus:
 
 class Recording:
     """
-    Class used to perform a recording.
+    Class used to perform a recording. Recording data can come in from a
+    different thread, that is supposed to call the `inCallback` method, with
+    audio data as an argument.
     """
 
     def __init__(
@@ -99,7 +101,6 @@ class Recording:
         logging.debug("Starting record....")
 
         self.indh = InDataHandler(streammgr, self.inCallback, self.resetCallback)
-        self.indh.start()
 
         if wait:
             logging.debug("Stop recording with CTRL-C")

src/lasp/pybind11/lasp_pyindatahandler.cpp

@@ -5,8 +5,10 @@
 #include "lasp_clip.h"
 #include "lasp_rtaps.h"
 #include "lasp_rtsignalviewer.h"
-#include "lasp_streammgr.h"
 #include "lasp_threadedindatahandler.h"
+#include "lasp_daqdata.h"
+#include "lasp_daq.h"
+#include "lasp_streammgr.h"
 #include <armadillo>
 #include <atomic>
 #include <chrono>
@@ -111,11 +113,11 @@ public:
     DEBUGTRACE_ENTER;
     /// Start should be called externally, as at constructor time no virtual
     /// functions should be called.
-    /* start(); */
+    startThread();
   }
   ~PyIndataHandler() {
     DEBUGTRACE_ENTER;
-    stop();
+    stopThread();
   }
   void reset(const Daq *daq) override final { reset_callback(daq); }
 
@@ -169,20 +171,13 @@ public:
 
 void init_datahandler(py::module &m) {
 
-  py::class_<InDataHandler> idh(m, "InDataHandler_base");
-  idh.def("start", &InDataHandler::start);
-  idh.def("stop", &InDataHandler::stop);
-
-  py::class_<ThreadedInDataHandler, InDataHandler> tidh(
-      m, "ThreadedInDataHandler");
-
   /// The C++ class is PyIndataHandler, but for Python, it is called
   /// InDataHandler
-  py::class_<PyIndataHandler, ThreadedInDataHandler> pyidh(m, "InDataHandler");
+  py::class_<PyIndataHandler> pyidh(m, "InDataHandler");
   pyidh.def(py::init<StreamMgr &, py::function, py::function>());
 
   /// Peak Programme Meter
-  py::class_<PPMHandler, ThreadedInDataHandler> ppm(m, "PPMHandler");
+  py::class_<PPMHandler> ppm(m, "PPMHandler");
   ppm.def(py::init<StreamMgr &, const d>());
   ppm.def(py::init<StreamMgr &>());
 
@@ -194,7 +189,7 @@ void init_datahandler(py::module &m) {
   });
 
   /// Clip Detector
-  py::class_<ClipHandler, ThreadedInDataHandler> clip(m, "ClipHandler");
+  py::class_<ClipHandler> clip(m, "ClipHandler");
   clip.def(py::init<StreamMgr &>());
 
   clip.def("getCurrentValue", [](const ClipHandler &clip) {
@@ -206,7 +201,7 @@ void init_datahandler(py::module &m) {
 
   /// Real time Aps
   ///
-  py::class_<RtAps, ThreadedInDataHandler> rtaps(m, "RtAps");
+  py::class_<RtAps> rtaps(m, "RtAps");
   rtaps.def(py::init<StreamMgr &,              // StreamMgr
                      Filter *const,            // FreqWeighting filter
                      const us,                 // Nfft
@@ -233,7 +228,7 @@ void init_datahandler(py::module &m) {
 
   /// Real time Signal Viewer
   ///
-  py::class_<RtSignalViewer, ThreadedInDataHandler> rtsv(m, "RtSignalViewer");
+  py::class_<RtSignalViewer> rtsv(m, "RtSignalViewer");
   rtsv.def(py::init<StreamMgr &, // StreamMgr
                     const d,     // Time history
                     const us,    // Resolution

src/lasp/pybind11/lasp_streammgr.cpp

@@ -1,4 +1,5 @@
 #include "lasp_streammgr.h"
+#include "lasp_indatahandler.h"
 #include <pybind11/numpy.h>
 #include <pybind11/pybind11.h>
 #include <pybind11/stl.h>