major design changes: use glib event loop for MIDI thread/UI; rework design of BaseUI...

[ardour.git] / libs / pbd / base_ui.cc

diff --git a/libs/pbd/base_ui.cc b/libs/pbd/base_ui.cc
index 015951f118cf825532cf943ade511d97e0c9266b..259a51d9549b806e16da2250c488c778e05189fd 100644 (file)
--- a/libs/pbd/base_ui.cc
+++ b/libs/pbd/base_ui.cc
@@ -33,36 +33,24 @@
 
 using namespace std;
 using namespace PBD;
+using namespace Glib;
        
-uint32_t BaseUI::rt_bit = 1;
+uint64_t BaseUI::rt_bit = 1;
 BaseUI::RequestType BaseUI::CallSlot = BaseUI::new_request_type();
 
-BaseUI::BaseUI (string str, bool with_signal_pipe)
-       : _name (str)
+BaseUI::BaseUI (const string& str)
+       : run_loop_thread (0)
+       , _name (str)
 {
-       /* odd pseudo-singleton semantics */
-
        base_ui_instance = this;
 
-       signal_pipe[0] = -1;
-       signal_pipe[1] = -1;
+       request_channel.ios()->connect (sigc::mem_fun (*this, &BaseUI::request_handler));
 
-       if (with_signal_pipe) {
-               if (setup_signal_pipe ()) {
-                       throw failed_constructor ();
-               }
-       }
+       /* derived class must set _ok */
 }
 
 BaseUI::~BaseUI()
 {
-       if (signal_pipe[0] >= 0) {
-               close (signal_pipe[0]);
-       } 
-
-       if (signal_pipe[1] >= 0) {
-               close (signal_pipe[1]);
-       } 
 }
 
 BaseUI::RequestType
@@ -78,32 +66,53 @@ BaseUI::new_request_type ()
        return rt;
 }
 
-int
-BaseUI::setup_signal_pipe ()
+void
+BaseUI::main_thread ()
+{
+       thread_init ();
+       _main_loop->run ();
+}
+
+void
+BaseUI::run ()
 {
-       /* setup the pipe that other threads send us notifications/requests
-          through.
+       /* to be called by UI's that need/want their own distinct, self-created event loop thread.
+          Derived classes should have set up a handler for IO on request_channel.ios()
        */
 
-       if (pipe (signal_pipe)) {
-               error << string_compose (_("%1-UI: cannot create error signal pipe (%2)"), _name, ::strerror (errno))
-                     << endmsg;
+       _main_loop = MainLoop::create (MainContext::create());
+       request_channel.ios()->attach (_main_loop->get_context());
+       run_loop_thread = Thread::create (mem_fun (*this, &BaseUI::main_thread), true);
+}
 
-               return -1;
-       }
+void
+BaseUI::quit ()
+{
+       _main_loop->quit ();
+       run_loop_thread->join ();
+}
+
+bool
+BaseUI::request_handler (Glib::IOCondition ioc)
+{
+       /* check the transport request pipe */
 
-       if (fcntl (signal_pipe[0], F_SETFL, O_NONBLOCK)) {
-               error << string_compose (_("%1-UI: cannot set O_NONBLOCK on signal read pipe (%2)"), _name, ::strerror (errno))
-                     << endmsg;
-               return -1;
+       if (ioc & ~IO_IN) {
+               _main_loop->quit ();
        }
 
-       if (fcntl (signal_pipe[1], F_SETFL, O_NONBLOCK)) {
-               error << string_compose (_("%1-UI: cannot set O_NONBLOCK on signal write pipe (%2)"), _name, ::strerror (errno))
-                     << endmsg;
-               return -1;
+       if (ioc & IO_IN) {
+               request_channel.drain ();
+               
+               /* there may been an error. we'd rather handle requests first,
+                  and then get IO_HUP or IO_ERR on the next loop.
+               */
+
+               /* handle requests */
+
+               handle_ui_requests ();
        }
 
-       return 0;
+       return true;
 }
-
+