some linuxVST GUI details: initialize lock, add a note.

diff --git a/gtk2_ardour/linux_vst_gui_support.cc b/gtk2_ardour/linux_vst_gui_support.cc
index c86fb946cc42c18ba6b2205173182a41112a76f3..a2f637a26c6e5446f47337504dbe89bc14fd0996 100644 (file)
--- a/gtk2_ardour/linux_vst_gui_support.cc
+++ b/gtk2_ardour/linux_vst_gui_support.cc
@@ -56,7 +56,7 @@ static VSTState * vstfx_first = NULL;
 
 const char magic[] = "VSTFX Plugin State v002";
 
-static int gui_quit = 0;
+static volatile int gui_quit = 0;
 
 /*This will be our connection to X*/
 
@@ -471,7 +471,7 @@ again:
                        clock1 = g_get_monotonic_time();
                }
 
-               if (may_sleep && elapsed_time_ms + 1 < LXVST_sched_timer_interval) {
+               if (!gui_quit && may_sleep && elapsed_time_ms + 1 < LXVST_sched_timer_interval) {
                        Glib::usleep(1000 * (LXVST_sched_timer_interval - elapsed_time_ms - 1));
                }
        }
@@ -487,6 +487,8 @@ normally started in globals.cc*/
 
 int vstfx_init (void* ptr)
 {
+       assert (gui_quit == 0);
+       pthread_mutex_init (&plugin_mutex, NULL);
 
        int thread_create_result;
 
@@ -553,7 +555,11 @@ void vstfx_exit()
        /*We need to pthread_join the gui_thread here so
        we know when it has stopped*/
 
+       // BEWARE: some Plugin GUIs can crash if the thread local storage is free()d
+       // after the shared library containing the destructor is already dl-closed.
+       // (e.g u-he LXVST GUI, crash in __nptl_deallocate_tsd) :(
        pthread_join(LXVST_gui_event_thread, NULL);
+       pthread_mutex_destroy (&plugin_mutex);
 }
 
 /*Adds a new plugin (VSTFX) instance to the linked list*/