Remove the source files which got transferred to libpbd
[ardour.git] / libs / ardour / session_transport.cc
index b98a044d89aa9f6c5e8000a8e5ebf7b29f492668..dec3683c196a5f3e33a11450ae4148a972b7f1e2 100644 (file)
 #include "pbd/enumwriter.h"
 #include "pbd/pthread_utils.h"
 #include "pbd/memento_command.h"
+#include "pbd/stacktrace.h"
 
 #include "midi++/mmc.h"
 #include "midi++/port.h"
-#include "midi++/manager.h"
 
 #include "ardour/audioengine.h"
 #include "ardour/auditioner.h"
@@ -41,6 +41,8 @@
 #include "ardour/click.h"
 #include "ardour/debug.h"
 #include "ardour/location.h"
+#include "ardour/profile.h"
+#include "ardour/scene_changer.h"
 #include "ardour/session.h"
 #include "ardour/slave.h"
 #include "ardour/operations.h"
@@ -87,7 +89,7 @@ Session::request_sync_source (Slave* new_slave)
 
        seamless = Config->get_seamless_loop ();
 
-       if (dynamic_cast<JACK_Slave*>(new_slave)) {
+       if (dynamic_cast<Engine_Slave*>(new_slave)) {
                /* JACK cannot support seamless looping at present */
                Config->set_seamless_loop (false);
        } else {
@@ -137,8 +139,8 @@ Session::request_track_speed (Track* tr, double speed)
 void
 Session::request_stop (bool abort, bool clear_state)
 {
-       SessionEvent* ev = new SessionEvent (SessionEvent::SetTransportSpeed, SessionEvent::Add, SessionEvent::Immediate, 0, 0.0, abort, clear_state);
-       DEBUG_TRACE (DEBUG::Transport, string_compose ("Request transport stop, abort = %1, clear state = %2\n", abort, clear_state));
+       SessionEvent* ev = new SessionEvent (SessionEvent::SetTransportSpeed, SessionEvent::Add, SessionEvent::Immediate, audible_frame(), 0.0, abort, clear_state);
+       DEBUG_TRACE (DEBUG::Transport, string_compose ("Request transport stop, audible %3 transport %4 abort = %1, clear state = %2\n", abort, clear_state, audible_frame(), _transport_frame));
        queue_event (ev);
 }
 
@@ -159,10 +161,11 @@ Session::force_locate (framepos_t target_frame, bool with_roll)
 }
 
 void
-Session::request_play_loop (bool yn, bool leave_rolling)
+Session::request_play_loop (bool yn, bool change_transport_roll)
 {
        SessionEvent* ev;
        Location *location = _locations->auto_loop_location();
+       double target_speed;
 
        if (location == 0 && yn) {
                error << _("Cannot loop - no loop range defined")
@@ -170,14 +173,44 @@ Session::request_play_loop (bool yn, bool leave_rolling)
                return;
        }
 
-       ev = new SessionEvent (SessionEvent::SetLoop, SessionEvent::Add, SessionEvent::Immediate, 0, (leave_rolling ? 1.0 : 0.0), yn);
-       DEBUG_TRACE (DEBUG::Transport, string_compose ("Request set loop = %1, leave rolling ? %2\n", yn, leave_rolling));
+       if (change_transport_roll) {
+               if (transport_rolling()) {
+                       /* start looping at current speed */
+                       target_speed = transport_speed ();
+               } else {
+                       /* currently stopped */
+                       if (yn) {
+                               /* start looping at normal speed */
+                               target_speed = 1.0;
+                       } else {
+                               target_speed = 0.0;
+                       }
+               }
+       } else {
+               /* leave the speed alone */
+               target_speed = transport_speed ();
+       }
+
+       ev = new SessionEvent (SessionEvent::SetLoop, SessionEvent::Add, SessionEvent::Immediate, 0, target_speed, yn);
+       DEBUG_TRACE (DEBUG::Transport, string_compose ("Request set loop = %1, change roll state ? %2\n", yn, change_transport_roll));
        queue_event (ev);
 
-       if (!leave_rolling && !yn && Config->get_seamless_loop() && transport_rolling()) {
-               // request an immediate locate to refresh the tracks
-               // after disabling looping
-               request_locate (_transport_frame-1, false);
+       if (yn) {
+               if (!change_transport_roll) {
+                       if (!transport_rolling()) {
+                               /* we're not changing transport state, but we do want
+                                  to set up position for the new loop. Don't
+                                  do this if we're rolling already.
+                               */
+                               request_locate (location->start(), false);
+                       }
+               }
+       } else {
+               if (!change_transport_roll && Config->get_seamless_loop() && transport_rolling()) {
+                       // request an immediate locate to refresh the tracks
+                       // after disabling looping
+                       request_locate (_transport_frame-1, false);
+               }
        }
 }
 
@@ -194,6 +227,14 @@ Session::request_play_range (list<AudioRange>* range, bool leave_rolling)
        queue_event (ev);
 }
 
+void
+Session::request_cancel_play_range ()
+{
+       SessionEvent* ev = new SessionEvent (SessionEvent::CancelPlayAudioRange, SessionEvent::Add, SessionEvent::Immediate, 0, 0);
+       queue_event (ev);
+}
+
+
 void
 Session::realtime_stop (bool abort, bool clear_state)
 {
@@ -216,27 +257,12 @@ Session::realtime_stop (bool abort, bool clear_state)
        for (RouteList::iterator i = r->begin (); i != r->end(); ++i) {
                (*i)->realtime_handle_transport_stopped ();
        }
+       
+       DEBUG_TRACE (DEBUG::Transport, string_compose ("stop complete, auto-return scheduled for return to %1\n", _requested_return_frame));
 
-       if (actively_recording()) {
-
-               /* move the transport position back to where the
-                  request for a stop was noticed. we rolled
-                  past that point to pick up delayed input (and/or to delick)
-               */
-
-               if (worst_playback_latency() > current_block_size) {
-                       /* we rolled past the stop point to pick up data that had
-                          not yet arrived. move back to where the stop occured.
-                       */
-                       decrement_transport_position (current_block_size + (worst_input_latency() - current_block_size));
-               } else {
-                       decrement_transport_position (current_block_size);
-               }
-
-               /* the duration change is not guaranteed to have happened, but is likely */
-
-               todo = PostTransportWork (todo | PostTransportDuration);
-       }
+       /* the duration change is not guaranteed to have happened, but is likely */
+       
+       todo = PostTransportWork (todo | PostTransportDuration);
 
        if (abort) {
                todo = PostTransportWork (todo | PostTransportAbort);
@@ -384,6 +410,7 @@ Session::butler_transport_work ()
        g_atomic_int_dec_and_test (&_butler->should_do_transport_work);
 
        DEBUG_TRACE (DEBUG::Transport, X_("Butler transport work all done\n"));
+       DEBUG_TRACE (DEBUG::Transport, X_(string_compose ("Frame %1\n", _transport_frame)));
 }
 
 void
@@ -423,6 +450,8 @@ Session::non_realtime_locate ()
                (*i)->non_realtime_locate (_transport_frame);
        }
 
+       _scene_changer->locate (_transport_frame);
+
        /* XXX: it would be nice to generate the new clicks here (in the non-RT thread)
           rather than clearing them so that the RT thread has to spend time constructing
           them (in Session::click).
@@ -498,6 +527,11 @@ Session::non_realtime_stop (bool abort, int on_entry, bool& finished)
 
        if (did_record) {
                commit_reversible_command ();
+               /* increase take name */
+               if (config.get_track_name_take () && !config.get_take_name ().empty()) {
+                       string newname = config.get_take_name();
+                       config.set_take_name(bump_name_number (newname));
+               }
        }
 
        if (_engine.running()) {
@@ -509,18 +543,18 @@ Session::non_realtime_stop (bool abort, int on_entry, bool& finished)
        }
 
        bool const auto_return_enabled =
-               (!config.get_external_sync() && config.get_auto_return());
+               (!config.get_external_sync() && (config.get_auto_return() || abort));
 
        if (auto_return_enabled ||
            (ptw & PostTransportLocate) ||
            (_requested_return_frame >= 0) ||
-           synced_to_jack()) {
+           synced_to_engine()) {
 
                if (pending_locate_flush) {
                        flush_all_inserts ();
                }
 
-               if ((auto_return_enabled || synced_to_jack() || _requested_return_frame >= 0) &&
+               if ((auto_return_enabled || synced_to_engine() || _requested_return_frame >= 0) &&
                    !(ptw & PostTransportLocate)) {
 
                        /* no explicit locate queued */
@@ -531,8 +565,6 @@ Session::non_realtime_stop (bool abort, int on_entry, bool& finished)
 
                                /* explicit return request pre-queued in event list. overrides everything else */
 
-                               cerr << "explicit auto-return to " << _requested_return_frame << endl;
-
                                _transport_frame = _requested_return_frame;
                                do_locate = true;
 
@@ -543,7 +575,7 @@ Session::non_realtime_stop (bool abort, int on_entry, bool& finished)
 
                                                /* don't try to handle loop play when synced to JACK */
 
-                                               if (!synced_to_jack()) {
+                                               if (!synced_to_engine()) {
 
                                                        Location *location = _locations->auto_loop_location();
 
@@ -571,6 +603,10 @@ Session::non_realtime_stop (bool abort, int on_entry, bool& finished)
                                                _transport_frame = _last_roll_location;
                                                do_locate = true;
                                        }
+                               } else if (abort) {
+
+                                       _transport_frame = _last_roll_location;
+                                       do_locate = true;
                                }
                        }
 
@@ -589,8 +625,10 @@ Session::non_realtime_stop (bool abort, int on_entry, bool& finished)
        */
 
        if (ptw & PostTransportClearSubstate) {
-               _play_range = false;
-               unset_play_loop ();
+               unset_play_range ();
+               if (!Config->get_loop_is_mode()) {
+                       unset_play_loop ();
+               }
        }
 
        /* this for() block can be put inside the previous if() and has the effect of ... ??? what */
@@ -609,11 +647,23 @@ Session::non_realtime_stop (bool abort, int on_entry, bool& finished)
 
        have_looped = false;
 
-       if (!_engine.freewheeling()) {
-               send_full_time_code (_transport_frame);
+       /* don't bother with this stuff if we're disconnected from the engine,
+          because there will be no process callbacks to deliver stuff from
+       */
+
+       if (_engine.connected() && !_engine.freewheeling()) {
+               // need to queue this in the next RT cycle
+               _send_timecode_update = true;
                
                if (!dynamic_cast<MTC_Slave*>(_slave)) {
-                       MIDI::Manager::instance()->mmc()->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdStop));
+                       send_immediate_mmc (MIDI::MachineControlCommand (MIDI::MachineControl::cmdStop));
+
+                       /* This (::non_realtime_stop()) gets called by main
+                          process thread, which will lead to confusion
+                          when calling AsyncMIDIPort::write().
+                          
+                          Something must be done. XXX
+                       */
                        send_mmc_locate (_transport_frame);
                }
        }
@@ -645,8 +695,10 @@ Session::non_realtime_stop (bool abort, int on_entry, bool& finished)
        }
 
        if (ptw & PostTransportStop) {
-               _play_range = false;
-               play_loop = false;
+               unset_play_range ();
+               if (!Config->get_loop_is_mode()) {
+                       unset_play_loop ();
+               }
        }
 
        PositionChanged (_transport_frame); /* EMIT SIGNAL */
@@ -683,8 +735,10 @@ Session::check_declick_out ()
                        start_locate (pending_locate_frame, pending_locate_roll, pending_locate_flush);
                        transport_sub_state &= ~(PendingDeclickOut|PendingLocate);
                } else {
-                       stop_transport (pending_abort);
-                       transport_sub_state &= ~(PendingDeclickOut|PendingLocate);
+                       if (!(transport_sub_state & StopPendingCapture)) {
+                               stop_transport (pending_abort);
+                               transport_sub_state &= ~(PendingDeclickOut|PendingLocate);
+                       }
                }
 
        } else if (transport_sub_state & PendingLoopDeclickOut) {
@@ -711,7 +765,7 @@ Session::unset_play_loop ()
 }
 
 void
-Session::set_play_loop (bool yn)
+Session::set_play_loop (bool yn, double speed)
 {
        /* Called from event-handling context */
 
@@ -722,7 +776,7 @@ Session::set_play_loop (bool yn)
                return;
        }
 
-       if (yn && Config->get_seamless_loop() && synced_to_jack()) {
+       if (yn && Config->get_seamless_loop() && synced_to_engine()) {
                warning << string_compose (
                        _("Seamless looping cannot be supported while %1 is using JACK transport.\n"
                          "Recommend changing the configured options"), PROGRAM_NAME)
@@ -770,12 +824,24 @@ Session::set_play_loop (bool yn)
                        merge_event (new SessionEvent (SessionEvent::AutoLoopDeclick, SessionEvent::Replace, dcp, dcl, 0.0f));
                        merge_event (new SessionEvent (SessionEvent::AutoLoop, SessionEvent::Replace, loc->end(), loc->start(), 0.0f));
 
-                       /* locate to start of loop and roll. 
+                       /* if requested to roll, locate to start of loop and
+                        * roll but ONLY if we're not already rolling.
 
                           args: positition, roll=true, flush=true, with_loop=false, force buffer refill if seamless looping
                        */
 
-                       start_locate (loc->start(), true, true, false, Config->get_seamless_loop());
+                       if (Config->get_loop_is_mode()) {
+                               /* loop IS a transport mode: if already
+                                  rolling, do not locate to loop start.
+                               */
+                               if (!transport_rolling() && (speed != 0.0)) {
+                                       start_locate (loc->start(), true, true, false, Config->get_seamless_loop());
+                               }
+                       } else {
+                               if (speed != 0.0) {
+                                       start_locate (loc->start(), true, true, false, Config->get_seamless_loop());
+                               }
+                       }
                }
 
        } else {
@@ -799,7 +865,12 @@ Session::flush_all_inserts ()
 void
 Session::start_locate (framepos_t target_frame, bool with_roll, bool with_flush, bool with_loop, bool force)
 {
-       if (synced_to_jack()) {
+       if (target_frame < 0) {
+               error << _("Locate called for negative sample position - ignored") << endmsg;
+               return;
+       }
+
+       if (synced_to_engine()) {
 
                double sp;
                framepos_t pos;
@@ -873,7 +944,7 @@ Session::locate (framepos_t target_frame, bool with_roll, bool with_flush, bool
 
        if (!force && _transport_frame == target_frame && !loop_changing && !for_seamless_loop) {
                if (with_roll) {
-                       set_transport_speed (1.0, false);
+                       set_transport_speed (1.0, 0, false);
                }
                loop_changing = false;
                Located (); /* EMIT SIGNAL */
@@ -914,7 +985,7 @@ Session::locate (framepos_t target_frame, bool with_roll, bool with_flush, bool
 
        bool transport_was_stopped = !transport_rolling();
 
-       if (transport_was_stopped && (!auto_play_legal || !config.get_auto_play()) && !with_roll && !(synced_to_jack() && play_loop)) {
+       if (transport_was_stopped && (!auto_play_legal || !config.get_auto_play()) && !with_roll && !(synced_to_engine() && play_loop)) {
                realtime_stop (false, true); // XXX paul - check if the 2nd arg is really correct
                transport_was_stopped = true;
        } else {
@@ -971,7 +1042,9 @@ Session::locate (framepos_t target_frame, bool with_roll, bool with_flush, bool
 
                                // located outside the loop: cancel looping directly, this is called from event handling context
 
-                               set_play_loop (false);
+                               if (!Config->get_loop_is_mode()) {
+                                       set_play_loop (false, _transport_speed);
+                               }
                                
                        } else if (_transport_frame == al->start()) {
 
@@ -1007,6 +1080,7 @@ Session::locate (framepos_t target_frame, bool with_roll, bool with_flush, bool
                send_mmc_locate (_transport_frame);
        }
 
+       _last_roll_location = _last_roll_or_reversal_location =  _transport_frame;
        Located (); /* EMIT SIGNAL */
 }
 
@@ -1015,7 +1089,7 @@ Session::locate (framepos_t target_frame, bool with_roll, bool with_flush, bool
  *  @param speed New speed
  */
 void
-Session::set_transport_speed (double speed, bool abort, bool clear_state, bool as_default)
+Session::set_transport_speed (double speed, framepos_t destination_frame, bool abort, bool clear_state, bool as_default)
 {
        DEBUG_TRACE (DEBUG::Transport, string_compose ("@ %5 Set transport speed to %1, abort = %2 clear_state = %3, current = %4 as_default %6\n", 
                                                       speed, abort, clear_state, _transport_speed, _transport_frame, as_default));
@@ -1053,8 +1127,8 @@ Session::set_transport_speed (double speed, bool abort, bool clear_state, bool a
                if (Config->get_monitoring_model() == HardwareMonitoring) {
                        set_track_monitor_input_status (true);
                }
-
-               if (synced_to_jack ()) {
+               
+               if (synced_to_engine ()) {
                        if (clear_state) {
                                /* do this here because our response to the slave won't
                                   take care of it.
@@ -1064,20 +1138,41 @@ Session::set_transport_speed (double speed, bool abort, bool clear_state, bool a
                        }
                        _engine.transport_stop ();
                } else {
+                       bool const auto_return_enabled = (!config.get_external_sync() && (config.get_auto_return() || abort));
+
+                       if (!auto_return_enabled) {
+                               _requested_return_frame = destination_frame;
+                       }
+
                        stop_transport (abort);
                }
 
-               unset_play_loop ();
+               if (!Config->get_loop_is_mode()) {
+                       unset_play_loop ();
+               }
 
        } else if (transport_stopped() && speed == 1.0) {
 
                /* we are stopped and we want to start rolling at speed 1 */
 
+               if (Config->get_loop_is_mode() && play_loop) {
+
+                       Location *location = _locations->auto_loop_location();
+                       
+                       if (location != 0) {
+                               if (_transport_frame != location->start()) {
+                                       /* jump to start and then roll from there */
+                                       request_locate (location->start(), true);
+                                       return;
+                               }
+                       }
+               }
+
                if (Config->get_monitoring_model() == HardwareMonitoring && config.get_auto_input()) {
                        set_track_monitor_input_status (false);
                }
 
-               if (synced_to_jack()) {
+               if (synced_to_engine()) {
                        _engine.transport_start ();
                } else {
                        start_transport ();
@@ -1087,7 +1182,7 @@ Session::set_transport_speed (double speed, bool abort, bool clear_state, bool a
 
                /* not zero, not 1.0 ... varispeed */
 
-               if ((synced_to_jack()) && speed != 0.0 && speed != 1.0) {
+               if ((synced_to_engine()) && speed != 0.0 && speed != 1.0) {
                        warning << string_compose (
                                _("Global varispeed cannot be supported while %1 is connected to JACK transport control"),
                                PROGRAM_NAME)
@@ -1154,59 +1249,77 @@ Session::stop_transport (bool abort, bool clear_state)
                return;
        }
 
-       if (actively_recording() && !(transport_sub_state & StopPendingCapture) && worst_input_latency() > current_block_size) {
+       if (!get_transport_declick_required()) {
+
+               /* stop has not yet been scheduled */
 
                boost::shared_ptr<RouteList> rl = routes.reader();
+               framepos_t stop_target = audible_frame();
+
                for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
                        boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
                        if (tr) {
-                               tr->prepare_to_stop (_transport_frame);
+                               tr->prepare_to_stop (_transport_frame, stop_target);
                        }
                }
 
-               /* we need to capture the audio that has still not yet been received by the system
-                  at the time the stop is requested, so we have to roll past that time.
-
-                  we want to declick before stopping, so schedule the autostop for one
-                  block before the actual end. we'll declick in the subsequent block,
-                  and then we'll really be stopped.
-               */
-
-               DEBUG_TRACE (DEBUG::Transport, string_compose ("stop transport requested @ %1, scheduled for + %2 - %3 = %4, abort = %5\n",
-                                                              _transport_frame, _worst_input_latency, current_block_size,
-                                                              _transport_frame - _worst_input_latency - current_block_size,
-                                                              abort));
-
-               SessionEvent *ev = new SessionEvent (SessionEvent::StopOnce, SessionEvent::Replace,
-                                                    _transport_frame + _worst_input_latency - current_block_size,
-                                                    0, 0, abort);
-
-               merge_event (ev);
-               transport_sub_state |= StopPendingCapture;
-               pending_abort = abort;
-               return;
-       }
-
-       if ((transport_sub_state & PendingDeclickOut) == 0) {
+               SubState new_bits;
+               
+               if (actively_recording() &&                           /* we are recording */
+                   worst_input_latency() > current_block_size) {     /* input latency exceeds block size, so simple 1 cycle delay before stop is not enough */
+                       
+                       /* we need to capture the audio that is still somewhere in the pipeline between
+                          wherever it was generated and the process callback. This means that even though
+                          the user (or something else)  has asked us to stop, we have to roll
+                          past this point and then reset the playhead/transport location to
+                          the position at which the stop was requested.
+
+                          we still need playback to "stop" now, however, which is why we schedule
+                          a declick below.
+                       */
+                       
+                       DEBUG_TRACE (DEBUG::Transport, string_compose ("stop transport requested @ %1, scheduled for + %2 = %3, abort = %4\n",
+                                                                      _transport_frame, _worst_input_latency,
+                                                                      _transport_frame + _worst_input_latency,
+                                                                      abort));
+                       
+                       SessionEvent *ev = new SessionEvent (SessionEvent::StopOnce, SessionEvent::Replace,
+                                                            _transport_frame + _worst_input_latency,
+                                                            0, 0, abort);
+                       
+                       merge_event (ev);
 
-               if (!(transport_sub_state & StopPendingCapture)) {
-                       boost::shared_ptr<RouteList> rl = routes.reader();
-                       for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
-                               boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
-                               if (tr) {
-                                       tr->prepare_to_stop (_transport_frame);
-                               }
-                       }
+                       /* request a declick at the start of the next process cycle() so that playback ceases.
+                          It will remain silent until we actually stop (at the StopOnce event somewhere in 
+                          the future). The extra flag (StopPendingCapture) is set to ensure that check_declick_out()
+                          does not stop the transport too early.
+                        */
+                       new_bits = SubState (PendingDeclickOut|StopPendingCapture);
+                       
+               } else {
+                       
+                       /* Not recording, schedule a declick in the next process() cycle and then stop at its end */
+                       
+                       new_bits = PendingDeclickOut;
                }
 
-               transport_sub_state |= PendingDeclickOut;
+               
                /* we'll be called again after the declick */
+               transport_sub_state = SubState (transport_sub_state|new_bits);
                pending_abort = abort;
+
                return;
-       }
 
-       realtime_stop (abort, clear_state);
-       _butler->schedule_transport_work ();
+       } else {
+               
+               /* declick was scheduled, but we've been called again, which means it is really time to stop
+                  
+                  XXX: we should probably split this off into its own method and call it explicitly.
+               */
+
+               realtime_stop (abort, clear_state);
+               _butler->schedule_transport_work ();
+       }
 }
 
 /** Called from the process thread */
@@ -1258,7 +1371,7 @@ Session::start_transport ()
                Timecode::Time time;
                timecode_time_subframes (_transport_frame, time);
                if (!dynamic_cast<MTC_Slave*>(_slave)) {
-                       MIDI::Manager::instance()->mmc()->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdDeferredPlay));
+                       send_immediate_mmc (MIDI::MachineControlCommand (MIDI::MachineControl::cmdDeferredPlay));
                }
        }
 
@@ -1336,8 +1449,9 @@ Session::use_sync_source (Slave* new_slave)
        _slave = new_slave;
 
        DEBUG_TRACE (DEBUG::Slave, string_compose ("set new slave to %1\n", _slave));
-
-       send_full_time_code (_transport_frame);
+       
+       // need to queue this for next process() cycle
+       _send_timecode_update = true;
 
        boost::shared_ptr<RouteList> rl = routes.reader();
        for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
@@ -1378,7 +1492,7 @@ Session::switch_to_sync_source (SyncSource src)
                }
 
                try {
-                       new_slave = new MTC_Slave (*this, *MIDI::Manager::instance()->mtc_input_port());
+                       new_slave = new MTC_Slave (*this, *_midi_ports->mtc_input_port());
                }
 
                catch (failed_constructor& err) {
@@ -1407,7 +1521,7 @@ Session::switch_to_sync_source (SyncSource src)
                }
 
                try {
-                       new_slave = new MIDIClock_Slave (*this, *MIDI::Manager::instance()->midi_clock_input_port(), 24);
+                       new_slave = new MIDIClock_Slave (*this, *_midi_ports->midi_clock_input_port(), 24);
                }
 
                catch (failed_constructor& err) {
@@ -1415,8 +1529,8 @@ Session::switch_to_sync_source (SyncSource src)
                }
                break;
 
-       case JACK:
-               if (_slave && dynamic_cast<JACK_Slave*>(_slave)) {
+       case Engine:
+               if (_slave && dynamic_cast<Engine_Slave*>(_slave)) {
                        return;
                }
 
@@ -1424,7 +1538,7 @@ Session::switch_to_sync_source (SyncSource src)
                        return;
                }
 
-               new_slave = new JACK_Slave (_engine.jack());
+               new_slave = new Engine_Slave (*AudioEngine::instance());
                break;
 
        default:
@@ -1541,6 +1655,13 @@ Session::request_bounded_roll (framepos_t start, framepos_t end)
        lar.push_back (ar);
        request_play_range (&lar, true);
 }
+
+void
+Session::set_requested_return_frame (framepos_t return_to)
+{
+       _requested_return_frame = return_to;
+}
+
 void
 Session::request_roll_at_and_return (framepos_t start, framepos_t return_to)
 {
@@ -1614,23 +1735,13 @@ Session::allow_auto_play (bool yn)
        auto_play_legal = yn;
 }
 
-void
-Session::reset_jack_connection (jack_client_t* jack)
-{
-       JACK_Slave* js;
-
-       if (_slave && ((js = dynamic_cast<JACK_Slave*> (_slave)) != 0)) {
-               js->reset_client (jack);
-       }
-}
-
 bool
 Session::maybe_stop (framepos_t limit)
 {
        if ((_transport_speed > 0.0f && _transport_frame >= limit) || (_transport_speed < 0.0f && _transport_frame == 0)) {
-               if (synced_to_jack () && config.get_jack_time_master ()) {
+               if (synced_to_engine () && config.get_jack_time_master ()) {
                        _engine.transport_stop ();
-               } else if (!synced_to_jack ()) {
+               } else if (!synced_to_engine ()) {
                        stop_transport ();
                }
                return true;
@@ -1641,10 +1752,14 @@ Session::maybe_stop (framepos_t limit)
 void
 Session::send_mmc_locate (framepos_t t)
 {
+       if (t < 0) {
+               return;
+       }
+
        if (!_engine.freewheeling()) {
                Timecode::Time time;
                timecode_time_subframes (t, time);
-               MIDI::Manager::instance()->mmc()->send (MIDI::MachineControlCommand (time));
+               send_immediate_mmc (MIDI::MachineControlCommand (time));
        }
 }