libjack: Implement basic session management via SIGUSR1 signal

resources/ui/carla_add_jack.ui

@@ -6,7 +6,7 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>468</width>
+    <width>471</width>
     <height>369</height>
    </rect>
   </property>
@@ -111,9 +111,6 @@
         </item>
         <item>
          <widget class="QLabel" name="label_6">
-          <property name="enabled">
-           <bool>false</bool>
-          </property>
           <property name="text">
            <string>Session Manager:</string>
           </property>
@@ -124,22 +121,22 @@
         </item>
         <item>
          <widget class="QComboBox" name="cb_session_mgr">
-          <property name="enabled">
-           <bool>false</bool>
+          <property name="currentIndex">
+           <number>1</number>
           </property>
           <item>
            <property name="text">
-            <string>None / Manual</string>
+            <string>None</string>
            </property>
           </item>
           <item>
            <property name="text">
-            <string>LADISH (SIGUSR1)</string>
+            <string>Auto</string>
            </property>
           </item>
           <item>
            <property name="text">
-            <string>Non Session Manager (OSC)</string>
+            <string>LADISH (SIGUSR1)</string>
            </property>
           </item>
          </widget>

source/backend/plugin/CarlaPluginJack.cpp

@@ -325,6 +325,16 @@ public:
     // -------------------------------------------------------------------
     // Set data (state)
 
+    void prepareForSave() noexcept override
+    {
+        {
+            const CarlaMutexLocker _cml(fShmNonRtClientControl.mutex);
+
+            fShmNonRtClientControl.writeOpcode(kPluginBridgeNonRtClientPrepareForSave);
+            fShmNonRtClientControl.commitWrite();
+        }
+    }
+
     // -------------------------------------------------------------------
     // Set data (internal stuff)
 

source/frontend/carla_database.py

@@ -1718,9 +1718,9 @@ class PluginDatabaseW(QDialog):
 
 class JackApplicationW(QDialog):
     SESSION_MGR_NONE   = 0
-    SESSION_MGR_JACK   = 1
-    SESSION_MGR_LADISH = 2
-    SESSION_MGR_LASH   = 3
+    SESSION_MGR_AUTO   = 1
+    SESSION_MGR_JACK   = 2
+    SESSION_MGR_LADISH = 3
     SESSION_MGR_NSM    = 4
 
     FLAG_CONTROL_WINDOW        = 0x01
@@ -1762,9 +1762,11 @@ class JackApplicationW(QDialog):
             name = os.path.basename(command.split(" ",1)[0])
 
         # TODO finalize flag definitions
-        #uiSessionMgrIndex = self.ui.cb_session_mgr.currentIndex()
-        #if uiSessionMgrIndex == 1:
-            #smgr = self.SESSION_MGR_LADISH
+        uiSessionMgrIndex = self.ui.cb_session_mgr.currentIndex()
+        if uiSessionMgrIndex == 1:
+            smgr = self.SESSION_MGR_AUTO
+        elif uiSessionMgrIndex == 2:
+            smgr = self.SESSION_MGR_LADISH
         #elif uiSessionMgrIndex == 2:
             #smgr = self.SESSION_MGR_NSM
 

source/libjack/libjack.cpp

@@ -940,6 +940,20 @@ bool CarlaJackAppClient::handleNonRtData()
 
         case kPluginBridgeNonRtClientPrepareForSave:
             {
+                if (fSessionManager == 1) // auto
+                {
+                    struct sigaction sig;
+                    carla_zeroStruct(sig);
+
+                    sigaction(SIGUSR1, nullptr, &sig);
+
+                    if (sig.sa_handler != nullptr)
+                        fSessionManager = 3;
+                }
+
+                if (fSessionManager == 3)
+                    ::kill(::getpid(), SIGUSR1);
+
                 const CarlaMutexLocker _cml(fShmNonRtServerControl.mutex);
 
                 fShmNonRtServerControl.writeOpcode(kPluginBridgeNonRtServerSaved);