explicitly unload all instruments on quit to circumvent a jackd freeze

engine/api.py

@@ -24,6 +24,8 @@ import logging; logger = logging.getLogger(__name__); logger.info("import")
 
 #Standard Library Modules
 from typing import List, Set, Dict, Tuple
+import atexit
+
 
 #Third Party Modules
 from calfbox import cbox
@@ -142,23 +144,44 @@ def startEngine(nsmClient, additionalData):
 
     callbacks._auditionerVolumeChanged()
 
+    atexit.register(unloadAllInstrumentSamples) #this will handle all python exceptions, but not segfaults of C modules.
     logger.info("Tembro api startEngine complete")
 
 
 def loadAllInstrumentSamples():
     """Actually load all instrument samples"""
+    logger.info(f"Loading all instruments.")
     for instrument in Instrument.allInstruments.values():
         callbacks._startLoadingSamples(*instrument.idKey)
         instrument.loadSamples()
         callbacks._instrumentStatusChanged(*instrument.idKey)
-    callbacks._dataChanged
+    callbacks._dataChanged()
+
+def unloadAllInstrumentSamples():
+    """Cleanup.
+    It turned out relying on cbox closes ports or so too fast for JACK (not confirmed).
+    If too many instruments (> ~12) were loaded the program will freeze on quit and freeze
+    JACK as well.
+    A controlled deactivating of instruments circumvents this.
+    #TODO: Fixing jack2 is out of scope for us. If that even is a jack2 error.
+
+    The order of atexit is the reverse order of registering. Since the template stopSession
+    is registered before api.startEngine it is safe to rely on atexit.
+
+    The function could also be used from the menu of course.
+    """
+    logger.info(f"Unloading all instruments.")
+    for instrument in Instrument.allInstruments.values():
+        if instrument.enabled:
+            instrument.disable()
+            callbacks._instrumentStatusChanged(*instrument.idKey)
+    callbacks._dataChanged() #Needs to be here to have incremental updates in the gui.
 
 def unloadInstrumentSamples(idkey:tuple):
     instrument = Instrument.allInstruments[idkey]
     instrument.disable()
     callbacks._instrumentStatusChanged(*instrument.idKey)
-    callbacks._dataChanged
-
+    callbacks._dataChanged()
 
 def loadInstrumentSamples(idkey:tuple):
     """Load one .sfz from a library."""
@@ -170,7 +193,7 @@ def loadInstrumentSamples(idkey:tuple):
 
     instrument.loadSamples()
     callbacks._instrumentStatusChanged(*instrument.idKey)
-    callbacks._dataChanged
+    callbacks._dataChanged()
 
 def chooseVariantByIndex(idkey:tuple, variantIndex:int):
     """Choose a variant of an already enabled instrument"""
@@ -178,7 +201,7 @@ def chooseVariantByIndex(idkey:tuple, variantIndex:int):
     instrument = Instrument.allInstruments[idkey]
     instrument.chooseVariantByIndex(variantIndex)
     callbacks._instrumentStatusChanged(*instrument.idKey)
-    callbacks._dataChanged
+    callbacks._dataChanged()
 
 def setInstrumentMixerVolume(idkey:tuple, value:float):
     """From 0 to -21.

engine/main.py

@@ -59,13 +59,11 @@ class Data(TemplateData):
         session = self.parentSession  #self.parentSession is already defined in template.data. We just want to work conveniently in init with it by creating a local var.
         self._processAfterInit()
 
-
     def _processAfterInit(self):
         session = self.parentSession #We just want to work conveniently in init with it by creating a local var.
 
         self.cachedSerializedDataForStartEngine = None
 
-
     def parseAndLoadInstrumentLibraries(self, baseSamplePath):
         """Called once by api.startEngine, which receives the global sample path from
         the GUI"""

qtgui/instrument.py

@@ -438,6 +438,9 @@ class GuiInstrument(QtWidgets.QTreeWidgetItem):
             self.mixSendDial.setEnabled(False)
             self.mixSendDial.setUpdatesEnabled(False)  #this is a hack to make the widget disappear. Because hiding a QTreeWidgetItem does not work.
 
+        self.parentTreeController.parentMainWindow.qtApp.processEvents() #actually show the new state, even if mass unloading (which did not work before. But loading worked!)
+
+
     def _mixSendDialContextMenuEvent(self, event):
         if self._cachedInstrumentStatus["mixerEnabled"]:
             mixerMuteText = QtCore.QCoreApplication.translate("InstrumentMixerLevelContextMenu", "Mute/Disable Mixer-Send for {}".format(self.instrumentDict["name"]))

qtgui/mainwindow.py

@@ -113,6 +113,7 @@ class MainWindow(TemplateMainWindow):
         #self.menu.addMenuEntry("menuEdit", "actionNils", "Nils", lambda: print("Merle"))
         self.menu.addMenuEntry("menuEdit", "actionSampleDirPathDialog", "Sample Files Location", ChooseDownloadDirectory)
         self.menu.addMenuEntry("menuEdit", "actionLoadSamples", QtCore.QCoreApplication.translate("Menu", "Load all Instrument Samples (slow!)"), api.loadAllInstrumentSamples)
+        self.menu.addMenuEntry("menuEdit", "actionUnloadSamples", QtCore.QCoreApplication.translate("Menu", "Unload all Instrument Samples (also slow.)"), api.unloadAllInstrumentSamples)
         #self.menu.connectMenuEntry("actionNils", lambda: print("Override"))
         self.menu.addSubmenu("menuView", QtCore.QCoreApplication.translate("Menu", "View"))