non-crashing (but also non-functional) integration of VBAP with panner "architecture"
[ardour.git] / libs / ardour / session.cc
index a643ee21c35d7035e4109d70449254bf84688ed6..dbb899a4d4912c2f9b5091ff566ad379f421c712 100644 (file)
@@ -17,7 +17,6 @@
 
 */
 
-#define __STDC_LIMIT_MACROS
 #include <stdint.h>
 
 #include <algorithm>
@@ -35,6 +34,8 @@
 #include <glibmm/miscutils.h>
 #include <glibmm/fileutils.h>
 
+#include <boost/algorithm/string/erase.hpp>
+
 #include "pbd/error.h"
 #include "pbd/boost_debug.h"
 #include "pbd/pathscanner.h"
@@ -43,6 +44,7 @@
 #include "pbd/stacktrace.h"
 #include "pbd/file_utils.h"
 #include "pbd/convert.h"
+#include "pbd/strsplit.h"
 
 #include "ardour/amp.h"
 #include "ardour/analyser.h"
 #include "ardour/tape_file_matcher.h"
 #include "ardour/tempo.h"
 #include "ardour/utils.h"
+#include "ardour/graph.h"
+#include "ardour/vbap_speakers.h"
 
-#include "midi++/jack.h"
+#include "midi++/port.h"
+#include "midi++/mmc.h"
+#include "midi++/manager.h"
 
 #include "i18n.h"
 
@@ -113,14 +119,16 @@ PBD::Signal1<void,std::string> Session::Dialog;
 PBD::Signal0<int> Session::AskAboutPendingState;
 PBD::Signal2<int,nframes_t,nframes_t> Session::AskAboutSampleRateMismatch;
 PBD::Signal0<void> Session::SendFeedback;
+PBD::Signal3<int,Session*,std::string,DataType> Session::MissingFile;
 
 PBD::Signal0<void> Session::TimecodeOffsetChanged;
-PBD::Signal0<void> Session::StartTimeChanged;
-PBD::Signal0<void> Session::EndTimeChanged;
+PBD::Signal1<void, framepos_t> Session::StartTimeChanged;
+PBD::Signal1<void, framepos_t> Session::EndTimeChanged;
 PBD::Signal0<void> Session::AutoBindingOn;
 PBD::Signal0<void> Session::AutoBindingOff;
 PBD::Signal2<void,std::string, std::string> Session::Exported;
 PBD::Signal1<int,boost::shared_ptr<Playlist> > Session::AskAboutPlaylistDeletion;
+PBD::Signal0<void> Session::Quit;
 
 static void clean_up_session_event (SessionEvent* ev) { delete ev; }
 const SessionEvent::RTeventCallback Session::rt_cleanup (clean_up_session_event);
@@ -131,48 +139,50 @@ Session::Session (AudioEngine &eng,
                   BusProfile* bus_profile,
                  string mix_template)
 
-       : _engine (eng),
-         _target_transport_speed (0.0),
-         _requested_return_frame (-1),
-         mmc (0),
-         _mmc_port (default_mmc_port),
-         _mtc_port (default_mtc_port),
-         _midi_port (default_midi_port),
-         _midi_clock_port (default_midi_clock_port),
-         _session_dir (new SessionDirectory(fullpath)),
-         state_tree (0),
-         _butler (new Butler (*this)),
-         _post_transport_work (0),
-         _send_timecode_update (false),
-         routes (new RouteList),
-         _total_free_4k_blocks (0),
-         _bundles (new BundleList),
-         _bundle_xml_node (0),
-         _click_io ((IO*) 0),
-         click_data (0),
-         click_emphasis_data (0),
-         main_outs (0),
-         _metadata (new SessionMetadata()),
-         _have_rec_enabled_track (false)
-
+       : _engine (eng)
+        , _target_transport_speed (0.0)
+        , _requested_return_frame (-1)
+        , _session_dir (new SessionDirectory(fullpath))
+        , state_tree (0)
+       , _state_of_the_state (Clean)
+        , _butler (new Butler (*this))
+        , _post_transport_work (0)
+        , _send_timecode_update (false)
+        , _all_route_group (new RouteGroup (*this, "all"))
+        , route_graph (new Graph(*this))
+        , routes (new RouteList)
+        , _total_free_4k_blocks (0)
+        , _bundles (new BundleList)
+        , _bundle_xml_node (0)
+        , _click_io ((IO*) 0)
+        , click_data (0)
+        , click_emphasis_data (0)
+        , main_outs (0)
+        , _metadata (new SessionMetadata())
+        , _have_rec_enabled_track (false)
+        , _suspend_timecode_transmission (0)
 {
+       _locations = new Locations (*this);
+               
        playlists.reset (new SessionPlaylists);
-       
+
+        _all_route_group->set_active (true, this);
+
        interpolation.add_channel_to (0, 0);
 
        if (!eng.connected()) {
                throw failed_constructor();
        }
 
-       n_physical_outputs = _engine.n_physical_outputs(DataType::AUDIO);
-       n_physical_inputs =  _engine.n_physical_inputs(DataType::AUDIO);
+       n_physical_outputs = _engine.n_physical_outputs ();
+       n_physical_inputs =  _engine.n_physical_inputs ();
 
        first_stage_init (fullpath, snapshot_name);
 
         _is_new = !Glib::file_test (_path, Glib::FileTest (G_FILE_TEST_EXISTS | G_FILE_TEST_IS_DIR));
 
        if (_is_new) {
-               if (create (mix_template, compute_initial_length(), bus_profile)) {
+               if (create (mix_template, bus_profile)) {
                        destroy ();
                        throw failed_constructor ();
                }
@@ -196,6 +206,9 @@ Session::Session (AudioEngine &eng,
                DirtyChanged (); /* EMIT SIGNAL */
        }
 
+       StartTimeChanged.connect_same_thread (*this, boost::bind (&Session::start_time_changed, this, _1));
+       EndTimeChanged.connect_same_thread (*this, boost::bind (&Session::end_time_changed, this, _1));
+
         _is_new = false;
 }
 
@@ -227,6 +240,10 @@ Session::destroy ()
 
        delete state_tree;
 
+        /* remove all stubfiles that might still be lurking */
+
+        cleanup_stubfiles ();
+
        /* reset dynamic state version back to default */
 
        Stateful::loading_state_version = 0;
@@ -234,6 +251,7 @@ Session::destroy ()
        _butler->drop_references ();
        delete _butler;
        delete midi_control_ui;
+        delete _all_route_group;
 
        if (click_data != default_click) {
                delete [] click_data;
@@ -264,7 +282,7 @@ Session::destroy ()
        RegionFactory::delete_all_regions ();
 
        DEBUG_TRACE (DEBUG::Destruction, "delete routes\n");
-       
+
        /* reset these three references to special routes before we do the usual route delete thing */
 
        auditioner.reset ();
@@ -303,13 +321,14 @@ Session::destroy ()
 
        Crossfade::set_buffer_size (0);
 
-       delete mmc;
-
        /* not strictly necessary, but doing it here allows the shared_ptr debugging to work */
        playlists.reset ();
 
        boost_debug_list_ptrs ();
 
+       delete _locations;
+        delete _speakers;
+
        DEBUG_TRACE (DEBUG::Destruction, "Session::destroy() done\n");
 }
 
@@ -394,22 +413,23 @@ Session::when_engine_running ()
 
                        /* default state for Click: dual-mono to first 2 physical outputs */
 
-                       for (int physport = 0; physport < 2; ++physport) {
-                               string physical_output = _engine.get_nth_physical_output (DataType::AUDIO, physport);
+                       vector<string> outs;
+                       _engine.get_physical_outputs (DataType::AUDIO, outs);
 
-                               if (physical_output.length()) {
-                                       if (_click_io->add_port (physical_output, this)) {
-                                               // relax, even though its an error
-                                      }
-                              }
-                      }
-
-                       if (_click_io->n_ports () > ChanCount::ZERO) {
-                               _clicking = Config->get_clicking ();
-                       }
+                       for (uint32_t physport = 0; physport < 2; ++physport) {
+                               if (outs.size() > physport) {
+                                       if (_click_io->add_port (outs[physport], this)) {
+                                               // relax, even though its an error
+                                       }
+                               }
+                       }
+                       
+                       if (_click_io->n_ports () > ChanCount::ZERO) {
+                               _clicking = Config->get_clicking ();
+                       }
                }
        }
-
+       
        catch (failed_constructor& err) {
                error << _("cannot setup Click I/O") << endmsg;
        }
@@ -424,6 +444,13 @@ Session::when_engine_running ()
 
        BootMessage (_("Set up standard connections"));
 
+       vector<string> inputs[DataType::num_types];
+       vector<string> outputs[DataType::num_types];
+       for (uint32_t i = 0; i < DataType::num_types; ++i) {
+               _engine.get_physical_inputs (DataType (DataType::Symbol (i)), inputs[i]);
+               _engine.get_physical_outputs (DataType (DataType::Symbol (i)), outputs[i]);
+       }
+
        /* Create a set of Bundle objects that map
           to the physical I/O currently available.  We create both
           mono and stereo bundles, so that the common cases of mono
@@ -434,28 +461,28 @@ Session::when_engine_running ()
 
        /* mono output bundles */
 
-       for (uint32_t np = 0; np < n_physical_outputs; ++np) {
+       for (uint32_t np = 0; np < outputs[DataType::AUDIO].size(); ++np) {
                char buf[32];
                snprintf (buf, sizeof (buf), _("out %" PRIu32), np+1);
 
                shared_ptr<Bundle> c (new Bundle (buf, true));
-               c->add_channel (_("mono"));
-               c->set_port (0, _engine.get_nth_physical_output (DataType::AUDIO, np));
+               c->add_channel (_("mono"), DataType::AUDIO);
+               c->set_port (0, outputs[DataType::AUDIO][np]);
 
                add_bundle (c);
        }
 
        /* stereo output bundles */
 
-       for (uint32_t np = 0; np < n_physical_outputs; np += 2) {
-               if (np + 1 < n_physical_outputs) {
+       for (uint32_t np = 0; np < outputs[DataType::AUDIO].size(); np += 2) {
+               if (np + 1 < outputs[DataType::AUDIO].size()) {
                        char buf[32];
                        snprintf (buf, sizeof(buf), _("out %" PRIu32 "+%" PRIu32), np + 1, np + 2);
                        shared_ptr<Bundle> c (new Bundle (buf, true));
-                       c->add_channel (_("L"));
-                       c->set_port (0, _engine.get_nth_physical_output (DataType::AUDIO, np));
-                       c->add_channel (_("R"));
-                       c->set_port (1, _engine.get_nth_physical_output (DataType::AUDIO, np + 1));
+                       c->add_channel (_("L"), DataType::AUDIO);
+                       c->set_port (0, outputs[DataType::AUDIO][np]);
+                       c->add_channel (_("R"), DataType::AUDIO);
+                       c->set_port (1, outputs[DataType::AUDIO][np + 1]);
 
                        add_bundle (c);
                }
@@ -463,34 +490,58 @@ Session::when_engine_running ()
 
        /* mono input bundles */
 
-       for (uint32_t np = 0; np < n_physical_inputs; ++np) {
+       for (uint32_t np = 0; np < inputs[DataType::AUDIO].size(); ++np) {
                char buf[32];
                snprintf (buf, sizeof (buf), _("in %" PRIu32), np+1);
 
                shared_ptr<Bundle> c (new Bundle (buf, false));
-               c->add_channel (_("mono"));
-               c->set_port (0, _engine.get_nth_physical_input (DataType::AUDIO, np));
+               c->add_channel (_("mono"), DataType::AUDIO);
+               c->set_port (0, inputs[DataType::AUDIO][np]);
 
                add_bundle (c);
        }
 
        /* stereo input bundles */
 
-       for (uint32_t np = 0; np < n_physical_inputs; np += 2) {
-               if (np + 1 < n_physical_inputs) {
+       for (uint32_t np = 0; np < inputs[DataType::AUDIO].size(); np += 2) {
+               if (np + 1 < inputs[DataType::AUDIO].size()) {
                        char buf[32];
                        snprintf (buf, sizeof(buf), _("in %" PRIu32 "+%" PRIu32), np + 1, np + 2);
 
                        shared_ptr<Bundle> c (new Bundle (buf, false));
-                       c->add_channel (_("L"));
-                       c->set_port (0, _engine.get_nth_physical_input (DataType::AUDIO, np));
-                       c->add_channel (_("R"));
-                       c->set_port (1, _engine.get_nth_physical_input (DataType::AUDIO, np + 1));
+                       c->add_channel (_("L"), DataType::AUDIO);
+                       c->set_port (0, inputs[DataType::AUDIO][np]);
+                       c->add_channel (_("R"), DataType::AUDIO);
+                       c->set_port (1, inputs[DataType::AUDIO][np + 1]);
 
                        add_bundle (c);
                }
        }
 
+       /* MIDI input bundles */
+
+       for (uint32_t np = 0; np < inputs[DataType::MIDI].size(); ++np) {
+               string n = inputs[DataType::MIDI][np];
+               boost::erase_first (n, X_("alsa_pcm:"));
+               
+               shared_ptr<Bundle> c (new Bundle (n, false));
+               c->add_channel ("", DataType::MIDI);
+               c->set_port (0, inputs[DataType::MIDI][np]);
+               add_bundle (c);
+       }
+               
+       /* MIDI output bundles */
+
+       for (uint32_t np = 0; np < outputs[DataType::MIDI].size(); ++np) {
+               string n = outputs[DataType::MIDI][np];
+               boost::erase_first (n, X_("alsa_pcm:"));
+
+               shared_ptr<Bundle> c (new Bundle (n, true));
+               c->add_channel ("", DataType::MIDI);
+               c->set_port (0, outputs[DataType::MIDI][np]);
+               add_bundle (c);
+       }
+
        BootMessage (_("Setup signal flow and plugins"));
 
        hookup_io ();
@@ -508,7 +559,10 @@ Session::when_engine_running ()
 
                        for (uint32_t n = 0; n < limit; ++n) {
                                Port* p = _master_out->output()->nth (n);
-                               string connect_to = _engine.get_nth_physical_output (DataType (p->type()), n);
+                               string connect_to;
+                               if (outputs[p->type()].size() > n) {
+                                       connect_to = outputs[p->type()][n];
+                               }
 
                                if (!connect_to.empty() && p->connected_to (connect_to) == false) {
                                        if (_master_out->output()->connect (p, connect_to, this)) {
@@ -568,13 +622,16 @@ Session::when_engine_running ()
                                } else {
                                         
                                        for (DataType::iterator t = DataType::begin(); t != DataType::end(); ++t) {
-                                               uint32_t mod = _engine.n_physical_outputs (*t);
+                                               uint32_t mod = n_physical_outputs.get (*t);
                                                uint32_t limit = _monitor_out->n_outputs().get(*t);
 
                                                for (uint32_t n = 0; n < limit; ++n) {
 
                                                        Port* p = _monitor_out->output()->ports().port(*t, n);
-                                                       string connect_to = _engine.get_nth_physical_output (*t, (n % mod));
+                                                       string connect_to;
+                                                       if (outputs[*t].size() > (n % mod)) {
+                                                               connect_to = outputs[*t][n % mod];
+                                                       }
 
                                                        if (!connect_to.empty()) {
                                                                if (_monitor_out->output()->connect (p, connect_to, this)) {
@@ -643,7 +700,7 @@ Session::hookup_io ()
        /* Tell all IO objects to connect themselves together */
 
        IO::enable_connecting ();
-       MIDI::JACK_MidiPort::MakeConnections ();
+       MIDI::Port::MakeConnections ();
 
        /* Now reset all panners */
 
@@ -700,13 +757,7 @@ Session::hookup_io ()
 void
 Session::playlist_length_changed ()
 {
-       /* we can't just increase session_range_location->end() if pl->get_maximum_extent()
-          if larger. if the playlist used to be the longest playlist,
-          and its now shorter, we have to decrease session_range_location->end(). hence,
-          we have to iterate over all diskstreams and check the
-          playlists currently in use.
-       */
-       find_current_end ();
+       update_session_range_location_marker ();
 }
 
 void
@@ -723,8 +774,7 @@ Session::track_playlist_changed (boost::weak_ptr<Track> wp)
                playlist->LengthChanged.connect_same_thread (*this, boost::bind (&Session::playlist_length_changed, this));
        }
 
-       /* see comment in playlist_length_changed () */
-       find_current_end ();
+       update_session_range_location_marker ();
 }
 
 bool
@@ -837,7 +887,7 @@ Session::set_auto_punch_location (Location* location)
 {
        Location* existing;
 
-       if ((existing = _locations.auto_punch_location()) != 0 && existing != location) {
+       if ((existing = _locations->auto_punch_location()) != 0 && existing != location) {
                punch_connections.drop_connections();
                existing->set_auto_punch (false, this);
                remove_event (existing->start(), SessionEvent::PunchIn);
@@ -874,7 +924,7 @@ Session::set_auto_loop_location (Location* location)
 {
        Location* existing;
 
-       if ((existing = _locations.auto_loop_location()) != 0 && existing != location) {
+       if ((existing = _locations->auto_loop_location()) != 0 && existing != location) {
                loop_connections.drop_connections ();
                existing->set_auto_loop (false, this);
                remove_event (existing->end(), SessionEvent::AutoLoop);
@@ -920,7 +970,7 @@ Session::locations_added (Location *)
 void
 Session::locations_changed ()
 {
-       _locations.apply (*this, &Session::handle_locations_changed);
+       _locations->apply (*this, &Session::handle_locations_changed);
 }
 
 void
@@ -962,25 +1012,33 @@ Session::handle_locations_changed (Locations::LocationList& locations)
 void
 Session::enable_record ()
 {
-       /* XXX really atomic compare+swap here */
-       if (g_atomic_int_get (&_record_status) != Recording) {
-               g_atomic_int_set (&_record_status, Recording);
-               _last_record_location = _transport_frame;
-               deliver_mmc(MIDI::MachineControl::cmdRecordStrobe, _last_record_location);
-
-               if (Config->get_monitoring_model() == HardwareMonitoring && config.get_auto_input()) {
-                       
-                       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->record_enabled ()) {
-                                       tr->monitor_input (true);
-                               }
-                       }
-               }
+        while (1) {
+                RecordState rs = (RecordState) g_atomic_int_get (&_record_status);
+                
+                if (rs == Recording) {
+                        break;
+                }
 
-               RecordStateChanged ();
-       }
+                if (g_atomic_int_compare_and_exchange (&_record_status, rs, Recording)) {
+                        
+                        _last_record_location = _transport_frame;
+                       MIDI::Manager::instance()->mmc()->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdRecordStrobe));
+                        
+                        if (Config->get_monitoring_model() == HardwareMonitoring && config.get_auto_input()) {
+                                
+                                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->record_enabled ()) {
+                                                tr->monitor_input (true);
+                                        }
+                                }
+                        }
+                        
+                        RecordStateChanged ();
+                        break;
+                }
+        }
 }
 
 void
@@ -992,19 +1050,13 @@ Session::disable_record (bool rt_context, bool force)
 
                if ((!Config->get_latched_record_enable () && !play_loop) || force) {
                        g_atomic_int_set (&_record_status, Disabled);
+                       MIDI::Manager::instance()->mmc()->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdRecordExit));
                } else {
                        if (rs == Recording) {
                                g_atomic_int_set (&_record_status, Enabled);
                        }
                }
 
-               // FIXME: timestamp correct? [DR]
-               // FIXME FIXME FIXME: rt_context?  this must be called in the process thread.
-               // does this /need/ to be sent in all cases?
-               if (rt_context) {
-                       deliver_mmc (MIDI::MachineControl::cmdRecordExit, _transport_frame);
-               }
-
                if (Config->get_monitoring_model() == HardwareMonitoring && config.get_auto_input()) {
 
                        boost::shared_ptr<RouteList> rl = routes.reader ();
@@ -1045,31 +1097,37 @@ Session::step_back_from_record ()
 void
 Session::maybe_enable_record ()
 {
+        if (_step_editors > 0) {
+                return;
+        }
+
        g_atomic_int_set (&_record_status, Enabled);
 
-       /* this function is currently called from somewhere other than an RT thread.
-          this save_state() call therefore doesn't impact anything.
+       /* This function is currently called from somewhere other than an RT thread.
+          This save_state() call therefore doesn't impact anything.  Doing it here
+          means that we save pending state of which sources the next record will use,
+          which gives us some chance of recovering from a crash during the record.
        */
-
+       
        save_state ("", true);
-
+       
        if (_transport_speed) {
                if (!config.get_punch_in()) {
                        enable_record ();
                }
        } else {
-               deliver_mmc (MIDI::MachineControl::cmdRecordPause, _transport_frame);
+               MIDI::Manager::instance()->mmc()->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdRecordPause));
                RecordStateChanged (); /* EMIT SIGNAL */
        }
 
        set_dirty();
 }
 
-nframes64_t
+framepos_t
 Session::audible_frame () const
 {
-       nframes64_t ret;
-       nframes64_t tf;
+       framepos_t ret;
+       framepos_t tf;
        nframes_t offset;
 
        /* the first of these two possible settings for "offset"
@@ -1322,15 +1380,15 @@ Session::resort_routes ()
                return;
        }
 
-
        {
-
                RCUWriter<RouteList> writer (routes);
                shared_ptr<RouteList> r = writer.get_copy ();
                resort_routes_using (r);
                /* writer goes out of scope and forces update */
        }
 
+       //route_graph->dump(1);
+
 #ifndef NDEBUG
         boost::shared_ptr<RouteList> rl = routes.reader ();
         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
@@ -1353,10 +1411,6 @@ Session::resort_routes_using (shared_ptr<RouteList> r)
 {
        RouteList::iterator i, j;
 
-       for (i = r->begin(); i != r->end(); ++i) {
-                (*i)->check_physical_connections ();
-        }
-
        for (i = r->begin(); i != r->end(); ++i) {
 
                (*i)->clear_fed_by ();
@@ -1388,102 +1442,18 @@ Session::resort_routes_using (shared_ptr<RouteList> r)
        RouteSorter cmp;
        r->sort (cmp);
 
-        find_route_levels (r);
+       route_graph->rechain (r);
 
 #ifndef NDEBUG
         DEBUG_TRACE (DEBUG::Graph, "Routes resorted, order follows:\n");
        for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
-               DEBUG_TRACE (DEBUG::Graph, string_compose ("\t%1 signal order %2 level %3\n", 
-                                                           (*i)->name(), (*i)->order_key ("signal"),
-                                                           (*i)->graph_level()));
+               DEBUG_TRACE (DEBUG::Graph, string_compose ("\t%1 signal order %2\n", 
+                                                           (*i)->name(), (*i)->order_key ("signal")));
        }
 #endif
 
 }
 
-void
-Session::find_route_levels (shared_ptr<RouteList> rl)
-{
-        uint32_t setcnt = 0;
-        uint32_t limit = rl->size();
-        RouteList last_level;
-        RouteList this_level;
-
-        for (RouteList::iterator r = rl->begin(); r != rl->end(); ++r) {
-                
-                /* find routes with direct physical connections,
-                   or routes with no connections at all. Mark them
-                   with "special" level values, and push them into
-                   the "last_level" set.
-                
-                   All other routes get marked with a graph level
-                   of -1, which indicates that it needs to be set.
-
-                */
-                
-                if ((*r)->physically_connected()) {
-                        last_level.push_back (*r);
-                        (*r)->set_graph_level (0);
-                        setcnt++;
-                } else if (!(*r)->output()->connected()) {
-                        last_level.push_back (*r);
-                        (*r)->set_graph_level (INT32_MAX/2);
-                        setcnt++;
-                } else {
-                        (*r)->set_graph_level (-1);
-                }
-        }
-
-        // until we've set the graph level for every route ... 
-
-        while (setcnt < limit) {
-
-                for (RouteList::reverse_iterator r = rl->rbegin(); r != rl->rend(); ++r) {
-
-                        int32_t l = INT32_MAX;
-                        bool found = false;
-
-                        if ((*r)->graph_level() != -1) {
-                                // we already have the graph level for this route
-                                continue;
-                        }
-
-                        /* check if this route (r) has a direction connection to anything in
-                           the set of routes we processed last time. On the first pass
-                           through this, last_level will contain routes with either
-                           no connections or direct "physical" connections. If there is
-                           at least 1 connection, store the lowest graph level of whatever
-                           r is connected to.
-                        */
-
-                        for (RouteList::iterator o = last_level.begin(); o != last_level.end(); ++o) {
-                                bool sends_only;
-                                if ((*r)->direct_feeds (*o, &sends_only)) {
-                                        if (!sends_only) {
-                                                l = min (l, (*o)->graph_level());
-                                                found = true;
-                                        }
-                                }
-                        }
-
-                        /* if we found any connections, then mark the graph level of r, and push
-                           it into the "this_level" set that will become "last_level" next time
-                           around the while() loop.
-                        */
-
-                        if (found) {
-                                (*r)->set_graph_level (l + 1);
-                                this_level.push_back (*r);
-                                setcnt++;
-                        }
-                }
-
-                last_level = this_level;
-                this_level.clear ();
-        }
-}
-
-
 /** Find the route name starting with \a base with the lowest \a id.
  *
  * Names are constructed like e.g. "Audio 3" for base="Audio" and id=3.
@@ -1510,6 +1480,7 @@ Session::find_route_name (const char* base, uint32_t& id, char* name, size_t nam
        return false;
 }
 
+/** Count the total ins and outs of all non-hidden routes in the session and return them in in and out */
 void
 Session::count_existing_route_channels (ChanCount& in, ChanCount& out)
 {
@@ -1518,8 +1489,8 @@ Session::count_existing_route_channels (ChanCount& in, ChanCount& out)
        shared_ptr<RouteList> r = routes.reader ();
        for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
                if (!(*i)->is_hidden()) {
-                       in += (*i)->n_inputs();
-                       out     += (*i)->n_outputs();
+                       in  += (*i)->n_inputs();
+                       out += (*i)->n_outputs();
                }
        }
 }
@@ -1547,7 +1518,7 @@ Session::new_midi_track (TrackMode mode, RouteGroup* route_group, uint32_t how_m
                }
 
                shared_ptr<MidiTrack> track;
-
+                
                try {
                        MidiTrack* mt = new MidiTrack (*this, track_name, Route::Flag (0), mode);
 
@@ -1572,9 +1543,10 @@ Session::new_midi_track (TrackMode mode, RouteGroup* route_group, uint32_t how_m
                                goto failed;
                        }
 
-                       auto_connect_route (track, existing_inputs, existing_outputs);
+                       auto_connect_route (track.get(), existing_inputs, existing_outputs);
 
                        track->non_realtime_input_change();
+
                        if (route_group) {
                                route_group->add (track);
                        }
@@ -1609,9 +1581,14 @@ Session::new_midi_track (TrackMode mode, RouteGroup* route_group, uint32_t how_m
        return ret;
 }
 
+/** @param connect_inputs true to connect inputs as well as outputs, false to connect just outputs.
+ *  @param input_start Where to start from when auto-connecting inputs; e.g. if this is 0, auto-connect starting from input 0.
+ *  @param output_start As \a input_start, but for outputs.
+ */
 void
-Session::auto_connect_route (boost::shared_ptr<Route> route,
-               ChanCount& existing_inputs, ChanCount& existing_outputs)
+Session::auto_connect_route (
+       Route* route, ChanCount& existing_inputs, ChanCount& existing_outputs, bool connect_inputs, ChanCount input_start, ChanCount output_start
+       )
 {
        /* If both inputs and outputs are auto-connected to physical ports,
           use the max of input and output offsets to ensure auto-connected
@@ -1620,9 +1597,11 @@ Session::auto_connect_route (boost::shared_ptr<Route> route,
           port number).  Otherwise just use the lowest input or output
           offset possible.
        */
+
        const bool in_out_physical =
                   (Config->get_input_auto_connect() & AutoConnectPhysical)
-               && (Config->get_output_auto_connect() & AutoConnectPhysical);
+               && (Config->get_output_auto_connect() & AutoConnectPhysical)
+               && connect_inputs;
 
        const ChanCount in_offset = in_out_physical
                ? ChanCount::max(existing_inputs, existing_outputs)
@@ -1632,9 +1611,6 @@ Session::auto_connect_route (boost::shared_ptr<Route> route,
                ? ChanCount::max(existing_inputs, existing_outputs)
                : existing_outputs;
 
-       static string empty_string;
-       string& port = empty_string;
-
        for (DataType::iterator t = DataType::begin(); t != DataType::end(); ++t) {
                vector<string> physinputs;
                vector<string> physoutputs;
@@ -1642,10 +1618,10 @@ Session::auto_connect_route (boost::shared_ptr<Route> route,
                _engine.get_physical_outputs (*t, physoutputs);
                _engine.get_physical_inputs (*t, physinputs);
 
-               if (!physinputs.empty()) {
+               if (!physinputs.empty() && connect_inputs) {
                        uint32_t nphysical_in = physinputs.size();
-                       for (uint32_t i = 0; i < route->n_inputs().get(*t) && i < nphysical_in; ++i) {
-                               port = empty_string;
+                       for (uint32_t i = input_start.get(*t); i < route->n_inputs().get(*t) && i < nphysical_in; ++i) {
+                               string port;
 
                                if (Config->get_input_auto_connect() & AutoConnectPhysical) {
                                        port = physinputs[(in_offset.get(*t) + i) % nphysical_in];
@@ -1660,8 +1636,8 @@ Session::auto_connect_route (boost::shared_ptr<Route> route,
 
                if (!physoutputs.empty()) {
                        uint32_t nphysical_out = physoutputs.size();
-                       for (uint32_t i = 0; i < route->n_outputs().get(*t); ++i) {
-                               port = empty_string;
+                       for (uint32_t i = output_start.get(*t); i < route->n_outputs().get(*t); ++i) {
+                               string port;
 
                                if (Config->get_output_auto_connect() & AutoConnectPhysical) {
                                        port = physoutputs[(out_offset.get(*t) + i) % nphysical_out];
@@ -1737,7 +1713,7 @@ Session::new_audio_track (int input_channels, int output_channels, TrackMode mod
                                goto failed;
                        }
 
-                       auto_connect_route (track, existing_inputs, existing_outputs);
+                       auto_connect_route (track.get(), existing_inputs, existing_outputs);
 
                        if (route_group) {
                                route_group->add (track);
@@ -1785,11 +1761,11 @@ Session::set_remote_control_ids ()
 
        for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
                if (MixerOrdered == m) {
-                       long order = (*i)->order_key(N_("signal"));
+                       int32_t order = (*i)->order_key(N_("signal"));
                        (*i)->set_remote_control_id (order+1, false);
                        emit_signal = true;
                } else if (EditorOrdered == m) {
-                       long order = (*i)->order_key(N_("editor"));
+                       int32_t order = (*i)->order_key(N_("editor"));
                        (*i)->set_remote_control_id (order+1, false);
                        emit_signal = true;
                } else if (UserOrdered == m) {
@@ -1850,7 +1826,7 @@ Session::new_audio_route (bool aux, int input_channels, int output_channels, Rou
                                goto failure;
                        }
 
-                       auto_connect_route (bus, existing_inputs, existing_outputs);
+                       auto_connect_route (bus.get(), existing_inputs, existing_outputs, false);
 
                        if (route_group) {
                                route_group->add (bus);
@@ -1918,13 +1894,19 @@ Session::new_route_from_template (uint32_t how_many, const std::string& template
                        /*NOTREACHED*/
                }
 
-               IO::set_name_in_state (*node_copy.children().front(), name);
+               /* set IO children to use the new name */
+               XMLNodeList const & children = node_copy.children ();
+               for (XMLNodeList::const_iterator i = children.begin(); i != children.end(); ++i) {
+                       if ((*i)->name() == IO::state_node_name) {
+                               IO::set_name_in_state (**i, name);
+                       }
+               }
 
                Track::zero_diskstream_id_in_xml (node_copy);
 
                try {
                        shared_ptr<Route> route (XMLRouteFactory (node_copy, 3000));
-           
+
                        if (route == 0) {
                                error << _("Session: cannot create track/bus from template description") << endmsg;
                                goto out;
@@ -1935,8 +1917,11 @@ Session::new_route_from_template (uint32_t how_many, const std::string& template
                                   picks up the configuration of the route. During session
                                   loading this normally happens in a different way.
                                */
-                               route->input()->changed (IOChange (ConfigurationChanged|ConnectionsChanged), this);
-                               route->output()->changed (IOChange (ConfigurationChanged|ConnectionsChanged), this);
+                               IOChange change (IOChange::Type (IOChange::ConfigurationChanged | IOChange::ConnectionsChanged));
+                               change.after = route->input()->n_ports();
+                               route->input()->changed (change, this);
+                               change.after = route->output()->n_ports();
+                               route->output()->changed (change, this);
                        }
 
                        route->set_remote_control_id (control_id);
@@ -1993,10 +1978,11 @@ Session::add_routes (RouteList& new_routes, bool save)
 
                r->listen_changed.connect_same_thread (*this, boost::bind (&Session::route_listen_changed, this, _1, wpr));
                r->solo_changed.connect_same_thread (*this, boost::bind (&Session::route_solo_changed, this, _1, _2, wpr));
+               r->solo_isolated_changed.connect_same_thread (*this, boost::bind (&Session::route_solo_isolated_changed, this, _1, wpr));
                r->mute_changed.connect_same_thread (*this, boost::bind (&Session::route_mute_changed, this, _1));
                r->output()->changed.connect_same_thread (*this, boost::bind (&Session::set_worst_io_latencies_x, this, _1, _2));
                r->processors_changed.connect_same_thread (*this, boost::bind (&Session::route_processors_changed, this, _1));
-               r->route_group_changed.connect_same_thread (*this, boost::bind (&Session::route_group_changed, this));
+               r->order_key_changed.connect_same_thread (*this, boost::bind (&Session::route_order_key_changed, this));
 
                if (r->is_master()) {
                        _master_out = r;
@@ -2011,6 +1997,11 @@ Session::add_routes (RouteList& new_routes, bool save)
                        tr->PlaylistChanged.connect_same_thread (*this, boost::bind (&Session::track_playlist_changed, this, boost::weak_ptr<Track> (tr)));
                        track_playlist_changed (boost::weak_ptr<Track> (tr));
                        tr->RecordEnableChanged.connect_same_thread (*this, boost::bind (&Session::update_have_rec_enabled_track, this));
+
+                        boost::shared_ptr<MidiTrack> mt = boost::dynamic_pointer_cast<MidiTrack> (tr);
+                        if (mt) {
+                                mt->StepEditStatusChange.connect_same_thread (*this, boost::bind (&Session::step_edit_status_change, this, _1));
+                        }
                }
        }
 
@@ -2135,6 +2126,12 @@ Session::add_internal_sends (boost::shared_ptr<Route> dest, Placement p, boost::
 void
 Session::remove_route (shared_ptr<Route> route)
 {
+        if (((route == _master_out) || (route == _monitor_out)) && !Config->get_allow_special_bus_removal()) {
+                return;
+        }
+
+        route->set_solo (false, this);
+
        {
                RCUWriter<RouteList> writer (routes);
                shared_ptr<RouteList> rs = writer.get_copy ();
@@ -2161,14 +2158,13 @@ Session::remove_route (shared_ptr<Route> route)
                        _monitor_out.reset ();
                }
 
-               update_route_solo_state ();
-
                /* writer goes out of scope, forces route list update */
        }
 
-       find_current_end ();
+        update_route_solo_state ();
+       update_session_range_location_marker ();
 
-       // We need to disconnect the routes inputs and outputs
+       // We need to disconnect the route's inputs and outputs
 
        route->input()->disconnect (0);
        route->output()->disconnect (0);
@@ -2185,9 +2181,23 @@ Session::remove_route (shared_ptr<Route> route)
                }
        }       
 
+        boost::shared_ptr<MidiTrack> mt = boost::dynamic_pointer_cast<MidiTrack> (route);
+        if (mt && mt->step_editing()) {
+                if (_step_editors > 0) {
+                        _step_editors--;
+                }
+        }
+
        update_latency_compensation (false, false);
        set_dirty();
 
+        /* Re-sort routes to remove the graph's current references to the one that is
+        * going away, then flush old references out of the graph.
+         */
+
+       resort_routes ();
+        route_graph->clear_other_chain ();
+
        /* get rid of it from the dead wood collection in the route list manager */
 
        /* XXX i think this is unsafe as it currently stands, but i am not sure. (pd, october 2nd, 2006) */
@@ -2225,12 +2235,55 @@ Session::route_listen_changed (void* /*src*/, boost::weak_ptr<Route> wpr)
        }
 
        if (route->listening()) {
+
+                if (Config->get_exclusive_solo()) {
+                        /* new listen: disable all other listen */
+                        shared_ptr<RouteList> r = routes.reader ();
+                        for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
+                                if ((*i) == route || (*i)->solo_isolated() || (*i)->is_master() || (*i)->is_monitor() || (*i)->is_hidden()) {
+                                        continue;
+                                } 
+                                (*i)->set_listen (false, this);
+                        }
+                }
+
                _listen_cnt++;
+
        } else if (_listen_cnt > 0) {
+
                _listen_cnt--;
        }
 }
+void
+Session::route_solo_isolated_changed (void* /*src*/, boost::weak_ptr<Route> wpr)
+{
+       boost::shared_ptr<Route> route = wpr.lock ();
+
+       if (!route) {
+               /* should not happen */
+               error << string_compose (_("programming error: %1"), X_("invalid route weak ptr passed to route_solo_changed")) << endmsg;
+               return;
+       }
+        
+        bool send_changed = false;
+
+        if (route->solo_isolated()) {
+                if (_solo_isolated_cnt == 0) {
+                        send_changed = true;
+                }
+                _solo_isolated_cnt++;
+        } else if (_solo_isolated_cnt > 0) {
+                _solo_isolated_cnt--;
+                if (_solo_isolated_cnt == 0) {
+                        send_changed = true;
+                }
+        }
 
+        if (send_changed) {
+                IsolatedChanged (); /* EMIT SIGNAL */
+        }
+}
+            
 void
 Session::route_solo_changed (bool self_solo_change, void* /*src*/, boost::weak_ptr<Route> wpr)
 {
@@ -2251,7 +2304,7 @@ Session::route_solo_changed (bool self_solo_change, void* /*src*/, boost::weak_p
                error << string_compose (_("programming error: %1"), X_("invalid route weak ptr passed to route_solo_changed")) << endmsg;
                return;
        }
-
+        
        shared_ptr<RouteList> r = routes.reader ();
        int32_t delta;
 
@@ -2260,21 +2313,19 @@ Session::route_solo_changed (bool self_solo_change, void* /*src*/, boost::weak_p
        } else {
                delta = -1;
        }
+        if (delta == 1 && Config->get_exclusive_solo()) {
+                /* new solo: disable all other solos */
+                for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
+                        if ((*i) == route || (*i)->solo_isolated() || (*i)->is_master() || (*i)->is_monitor() || (*i)->is_hidden()) {
+                                continue;
+                        } 
+                        (*i)->set_solo (false, this);
+                }
+        }
 
        solo_update_disabled = true;
-
-        /*
-
-           solo a route:
-              for anything in the signal path for this route, increment its soloed-by-other count
-              for anything not in the signal path for this route, increment its muted-by-other count
-
-           unsolo a route:
-              for anything in the signal path for this route, decrement its soloed-by-other count
-              for anything not in the signal path for this route, decrement its muted-by-other count
-
-        */
-
+        
         RouteList uninvolved;
         
        for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
@@ -2287,30 +2338,15 @@ Session::route_solo_changed (bool self_solo_change, void* /*src*/, boost::weak_p
 
                 in_signal_flow = false;
 
-                /* feed-backwards (other route to solo change route):
-
-                        if (*i) feeds the one whose solo status changed 
-                             it should be soloed by other if the change was -> solo OR de-soloed by other if change was -> !solo
-                        else 
-                             do nothing
-                            
-                 */
-
                 if ((*i)->feeds (route, &via_sends_only)) {
                        if (!via_sends_only) {
-                               (*i)->mod_solo_by_others_downstream (delta);
+                                if (!route->soloed_by_others_upstream()) {
+                                        (*i)->mod_solo_by_others_downstream (delta);
+                                }
                                 in_signal_flow = true;
                        }
                } 
                 
-                /* feed-forward (solo change route to other routes):
-                    
-                      if the route whose solo status changed feeds (*i)
-                             do nothing
-                      else 
-                             mute if the change was -> solo OR demute if change was -> !solo
-                 */
-
                 if (route->feeds (*i, &via_sends_only)) {
                         (*i)->mod_solo_by_others_upstream (delta);
                         in_signal_flow = true;
@@ -2343,6 +2379,7 @@ Session::update_route_solo_state (boost::shared_ptr<RouteList> r)
 
        bool something_soloed = false;
         uint32_t listeners = 0;
+        uint32_t isolated = 0;
 
        if (!r) {
                r = routes.reader();
@@ -2351,7 +2388,6 @@ Session::update_route_solo_state (boost::shared_ptr<RouteList> r)
        for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
                if (!(*i)->is_master() && !(*i)->is_monitor() && !(*i)->is_hidden() && (*i)->self_soloed()) {
                        something_soloed = true;
-                       break;
                }
 
                 if (!(*i)->is_hidden() && (*i)->listening()) {
@@ -2361,6 +2397,10 @@ Session::update_route_solo_state (boost::shared_ptr<RouteList> r)
                                 (*i)->set_listen (false, this);
                         }
                 }
+
+                if ((*i)->solo_isolated()) {
+                        isolated++;
+                }
        }
 
         if (something_soloed != _non_soloed_outs_muted) {
@@ -2368,8 +2408,11 @@ Session::update_route_solo_state (boost::shared_ptr<RouteList> r)
                 SoloActive (_non_soloed_outs_muted); /* EMIT SIGNAL */
         }
 
-        if (listeners) {
-                 _listen_cnt = listeners;
+        _listen_cnt = listeners;
+
+        if (isolated != _solo_isolated_cnt) {
+                _solo_isolated_cnt = isolated;
+                IsolatedChanged (); /* EMIT SIGNAL */
         }
 }
 
@@ -2447,43 +2490,64 @@ Session::route_by_remote_id (uint32_t id)
        return shared_ptr<Route> ((Route*) 0);
 }
 
+/** If either end of the session range location marker lies inside the current
+ *  session extent, move it to the corresponding session extent.
+ */
 void
-Session::find_current_end ()
+Session::update_session_range_location_marker ()
 {
        if (_state_of_the_state & Loading) {
                return;
        }
 
-       nframes_t max = get_maximum_extent ();
+       pair<framepos_t, framepos_t> const ext = get_extent ();
 
-       if (max > _session_range_location->end()) {
-               _session_range_location->set_end (max);
-               set_dirty();
-               DurationChanged(); /* EMIT SIGNAL */
+       if (_session_range_location == 0) {
+               /* we don't have a session range yet; use this one (provided it is valid) */
+               if (ext.first != max_framepos) {
+                       add_session_range_location (ext.first, ext.second);
+               }
+       } else {
+               /* update the existing session range */
+               if (ext.first < _session_range_location->start()) {
+                       _session_range_location->set_start (ext.first);
+                       set_dirty ();
+               }
+               
+               if (ext.second > _session_range_location->end()) {
+                       _session_range_location->set_end (ext.second);
+                       set_dirty ();
+               }
+               
        }
 }
 
-nframes_t
-Session::get_maximum_extent () const
+/** @return Extent of the session's contents; if the session is empty, the first value of
+ *  the pair will equal max_framepos.
+ */
+pair<framepos_t, framepos_t>
+Session::get_extent () const
 {
-       nframes_t max = 0;
-       nframes_t me;
+       pair<framepos_t, framepos_t> ext (max_framepos, 0);
        
        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->destructive()) {
-                       //ignore tape tracks when getting max extents
+                       // ignore tape tracks when getting extents
                        continue;
                }
-               
-               boost::shared_ptr<Playlist> pl = tr->playlist();
-               if ((me = pl->get_maximum_extent()) > max) {
-                       max = me;
+
+               pair<framepos_t, framepos_t> e = tr->playlist()->get_extent ();
+               if (e.first < ext.first) {
+                       ext.first = e.first;
+               }
+               if (e.second > ext.second) {
+                       ext.second = e.second;
                }
        }
 
-       return max;
+       return ext;
 }
 
 /* Region management */
@@ -2513,46 +2577,58 @@ Session::find_whole_file_parent (boost::shared_ptr<Region const> child) const
 }
 
 int
-Session::destroy_region (boost::shared_ptr<Region> region)
+Session::destroy_sources (list<boost::shared_ptr<Source> > srcs)
 {
-       vector<boost::shared_ptr<Source> > srcs;
+        set<boost::shared_ptr<Region> > relevant_regions;
 
-       {
-               if (region->playlist()) {
-                       region->playlist()->destroy_region (region);
-               }
-
-               for (uint32_t n = 0; n < region->n_channels(); ++n) {
-                       srcs.push_back (region->source (n));
-               }
+       for (list<boost::shared_ptr<Source> >::iterator s = srcs.begin(); s != srcs.end(); ++s) {
+                RegionFactory::get_regions_using_source (*s, relevant_regions);
        }
 
-       region->drop_references ();
+        cerr << "There are " << relevant_regions.size() << " using " << srcs.size() << " sources" << endl;
+
+        for (set<boost::shared_ptr<Region> >::iterator r = relevant_regions.begin(); r != relevant_regions.end(); ) {
+                set<boost::shared_ptr<Region> >::iterator tmp;
+
+                tmp = r;
+                ++tmp;
 
-       for (vector<boost::shared_ptr<Source> >::iterator i = srcs.begin(); i != srcs.end(); ++i) {
+                cerr << "Cleanup " << (*r)->name() << " UC = " << (*r).use_count() << endl;
+
+                playlists->destroy_region (*r);
+                RegionFactory::map_remove (*r);
+
+                (*r)->drop_sources ();
+                (*r)->drop_references ();
+
+                cerr << "\tdone UC = " << (*r).use_count() << endl;
+
+                relevant_regions.erase (r);
+
+                r = tmp;
+        }
 
-                (*i)->mark_for_remove ();
-                (*i)->drop_references ();
+       for (list<boost::shared_ptr<Source> >::iterator s = srcs.begin(); s != srcs.end(); ) {
                 
-                cerr << "source was not used by any playlist\n";
-       }
+                {
+                        Glib::Mutex::Lock ls (source_lock);
+                        /* remove from the main source list */
+                        sources.erase ((*s)->id());
+                }
 
-       return 0;
-}
+                (*s)->mark_for_remove ();
+                (*s)->drop_references ();
+
+                s = srcs.erase (s);
+        }
 
-int
-Session::destroy_regions (list<boost::shared_ptr<Region> > regions)
-{
-       for (list<boost::shared_ptr<Region> >::iterator i = regions.begin(); i != regions.end(); ++i) {
-               destroy_region (*i);
-       }
        return 0;
 }
 
 int
 Session::remove_last_capture ()
 {
-       list<boost::shared_ptr<Region> > r;
+       list<boost::shared_ptr<Source> > srcs;
 
        boost::shared_ptr<RouteList> rl = routes.reader ();
        for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
@@ -2561,15 +2637,15 @@ Session::remove_last_capture ()
                        continue;
                }
                
-               list<boost::shared_ptr<Region> >& l = tr->last_capture_regions();
+               list<boost::shared_ptr<Source> >& l = tr->last_capture_sources();
 
                if (!l.empty()) {
-                       r.insert (r.end(), l.begin(), l.end());
+                       srcs.insert (srcs.end(), l.begin(), l.end());
                        l.clear ();
                }
        }
 
-       destroy_regions (r);
+       destroy_sources (srcs);
 
        save_state (_current_snapshot_name);
 
@@ -2593,16 +2669,19 @@ Session::add_source (boost::shared_ptr<Source> source)
        }
 
        if (result.second) {
-               set_dirty();
-       }
 
-       boost::shared_ptr<AudioFileSource> afs;
+                /* yay, new source */
 
-       if ((afs = boost::dynamic_pointer_cast<AudioFileSource>(source)) != 0) {
-               if (Config->get_auto_analyse_audio()) {
-                       Analyser::queue_source_for_analysis (source, false);
-               }
-       }
+               set_dirty();
+
+                boost::shared_ptr<AudioFileSource> afs;
+                
+                if ((afs = boost::dynamic_pointer_cast<AudioFileSource>(source)) != 0) {
+                        if (Config->get_auto_analyse_audio()) {
+                                Analyser::queue_source_for_analysis (source, false);
+                        }
+                }
+        }
 }
 
 void
@@ -2619,6 +2698,7 @@ Session::remove_source (boost::weak_ptr<Source> src)
                Glib::Mutex::Lock lm (source_lock);
 
                if ((i = sources.find (source->id())) != sources.end()) {
+                        cerr << "Removing source " << source->name() << endl;
                        sources.erase (i);
                }
        }
@@ -2648,12 +2728,11 @@ Session::source_by_id (const PBD::ID& id)
 }
 
 boost::shared_ptr<Source>
-Session::source_by_path_and_channel (const Glib::ustring& path, uint16_t chn)
+Session::source_by_path_and_channel (const string& path, uint16_t chn)
 {
        Glib::Mutex::Lock lm (source_lock);
 
        for (SourceMap::iterator i = sources.begin(); i != sources.end(); ++i) {
-               cerr << "comparing " << path << " with " << i->second->name() << endl;
                boost::shared_ptr<AudioFileSource> afs
                        = boost::dynamic_pointer_cast<AudioFileSource>(i->second);
 
@@ -2664,6 +2743,24 @@ Session::source_by_path_and_channel (const Glib::ustring& path, uint16_t chn)
        return boost::shared_ptr<Source>();
 }
 
+uint32_t
+Session::count_sources_by_origin (const string& path)
+{
+        uint32_t cnt = 0;
+       Glib::Mutex::Lock lm (source_lock);
+
+       for (SourceMap::iterator i = sources.begin(); i != sources.end(); ++i) {
+               boost::shared_ptr<FileSource> fs
+                       = boost::dynamic_pointer_cast<FileSource>(i->second);
+
+                if (fs && fs->origin() == path) {
+                        ++cnt;
+                }
+       }
+
+       return cnt;
+}
+
 
 string
 Session::change_source_path_by_name (string path, string oldname, string newname, bool destructive)
@@ -2683,18 +2780,12 @@ Session::change_source_path_by_name (string path, string oldname, string newname
                    the task here is to replace NAME with the new name.
                */
 
-               /* find last slash */
-
                string dir;
                string prefix;
-               string::size_type slash;
                string::size_type dash;
 
-               if ((slash = path.find_last_of ('/')) == string::npos) {
-                       return "";
-               }
-
-               dir = path.substr (0, slash+1);
+               dir = Glib::path_get_dirname (path);
+                path = Glib::path_get_basename (path);
 
                /* '-' is not a legal character for the NAME part of the path */
 
@@ -2702,13 +2793,14 @@ Session::change_source_path_by_name (string path, string oldname, string newname
                        return "";
                }
 
-               prefix = path.substr (slash+1, dash-(slash+1));
+               prefix = path.substr (0, dash);
 
-               path = dir;
                path += prefix;
                path += '-';
                path += new_legalized;
-               path += ".wav";  /* XXX gag me with a spoon */
+               path += native_header_format_extension (config.get_native_file_header_format(), DataType::AUDIO);
+
+                path = Glib::build_filename (dir, path);
 
        } else {
 
@@ -2721,17 +2813,11 @@ Session::change_source_path_by_name (string path, string oldname, string newname
 
                string dir;
                string suffix;
-               string::size_type slash;
                string::size_type dash;
                string::size_type postfix;
 
-               /* find last slash */
-
-               if ((slash = path.find_last_of ('/')) == string::npos) {
-                       return "";
-               }
-
-               dir = path.substr (0, slash+1);
+               dir = Glib::path_get_dirname (path);
+                path = Glib::path_get_basename (path);
 
                /* '-' is not a legal character for the NAME part of the path */
 
@@ -2761,19 +2847,21 @@ Session::change_source_path_by_name (string path, string oldname, string newname
 
                for (uint32_t cnt = 1; cnt <= limit; ++cnt) {
 
-                       snprintf (buf, sizeof(buf), "%s%s-%u%s", dir.c_str(), newname.c_str(), cnt, suffix.c_str());
+                       snprintf (buf, sizeof(buf), "%s-%u%s", newname.c_str(), cnt, suffix.c_str());
 
-                       if (access (buf, F_OK) != 0) {
-                               path = buf;
+                        if (!matching_unsuffixed_filename_exists_in (dir, buf)) {
+                                path = Glib::build_filename (dir, buf);
                                break;
                        }
+
                        path = "";
                }
 
-               if (path == "") {
-                       error << "FATAL ERROR! Could not find a " << endl;
+               if (path.empty()) {
+                       fatal << string_compose (_("FATAL ERROR! Could not find a suitable version of %1 for a rename"),
+                                                 newname) << endl;
+                        /*NOTREACHED*/
                }
-
        }
 
        return path;
@@ -2784,7 +2872,7 @@ Session::change_source_path_by_name (string path, string oldname, string newname
  *         (e.g. as returned by new_*_source_name)
  */
 string
-Session::new_source_path_from_name (DataType type, const string& name)
+Session::new_source_path_from_name (DataType type, const string& name, bool as_stub)
 {
        assert(name.find("/") == string::npos);
 
@@ -2792,9 +2880,9 @@ Session::new_source_path_from_name (DataType type, const string& name)
 
        sys::path p;
        if (type == DataType::AUDIO) {
-               p = sdir.sound_path();
+               p = (as_stub ? sdir.sound_stub_path() : sdir.sound_path());
        } else if (type == DataType::MIDI) {
-               p = sdir.midi_path();
+               p = (as_stub ? sdir.midi_stub_path() : sdir.midi_path());
        } else {
                error << "Unknown source type, unable to create file path" << endmsg;
                return "";
@@ -2804,11 +2892,11 @@ Session::new_source_path_from_name (DataType type, const string& name)
        return p.to_string();
 }
 
-Glib::ustring
-Session::peak_path (Glib::ustring base) const
+string
+Session::peak_path (string base) const
 {
        sys::path peakfile_path(_session_dir->peak_path());
-       peakfile_path /= basename_nosuffix (base) + peakfile_suffix;
+       peakfile_path /= base + peakfile_suffix;
        return peakfile_path.to_string();
 }
 
@@ -2816,11 +2904,11 @@ Session::peak_path (Glib::ustring base) const
 string
 Session::new_audio_source_name (const string& base, uint32_t nchan, uint32_t chan, bool destructive)
 {
-       string spath;
        uint32_t cnt;
        char buf[PATH_MAX+1];
        const uint32_t limit = 10000;
        string legalized;
+        string ext = native_header_format_extension (config.get_native_file_header_format(), DataType::AUDIO);
 
        buf[0] = '\0';
        legalized = legalize_for_path (base);
@@ -2833,55 +2921,60 @@ Session::new_audio_source_name (const string& base, uint32_t nchan, uint32_t cha
 
                for (i = session_dirs.begin(); i != session_dirs.end(); ++i) {
 
-                       SessionDirectory sdir((*i).path);
-
-                       spath = sdir.sound_path().to_string();
-
                        if (destructive) {
 
                                if (nchan < 2) {
-                                       snprintf (buf, sizeof(buf), "%s/T%04d-%s.wav",
-                                                       spath.c_str(), cnt, legalized.c_str());
+                                       snprintf (buf, sizeof(buf), "T%04d-%s%s",
+                                                  cnt, legalized.c_str(), ext.c_str());
                                } else if (nchan == 2) {
                                        if (chan == 0) {
-                                               snprintf (buf, sizeof(buf), "%s/T%04d-%s%%L.wav",
-                                                               spath.c_str(), cnt, legalized.c_str());
+                                               snprintf (buf, sizeof(buf), "T%04d-%s%%L%s",
+                                                          cnt, legalized.c_str(), ext.c_str());
                                        } else {
-                                               snprintf (buf, sizeof(buf), "%s/T%04d-%s%%R.wav",
-                                                               spath.c_str(), cnt, legalized.c_str());
+                                               snprintf (buf, sizeof(buf), "T%04d-%s%%R%s",
+                                                          cnt, legalized.c_str(), ext.c_str());
                                        }
                                } else if (nchan < 26) {
-                                       snprintf (buf, sizeof(buf), "%s/T%04d-%s%%%c.wav",
-                                                       spath.c_str(), cnt, legalized.c_str(), 'a' + chan);
+                                       snprintf (buf, sizeof(buf), "T%04d-%s%%%c%s",
+                                                  cnt, legalized.c_str(), 'a' + chan, ext.c_str());
                                } else {
-                                       snprintf (buf, sizeof(buf), "%s/T%04d-%s.wav",
-                                                       spath.c_str(), cnt, legalized.c_str());
+                                       snprintf (buf, sizeof(buf), "T%04d-%s%s",
+                                                  cnt, legalized.c_str(), ext.c_str());
                                }
 
                        } else {
 
-                               spath += '/';
-                               spath += legalized;
-
                                if (nchan < 2) {
-                                       snprintf (buf, sizeof(buf), "%s-%u.wav", spath.c_str(), cnt);
+                                       snprintf (buf, sizeof(buf), "%s-%u%s", legalized.c_str(), cnt, ext.c_str());
                                } else if (nchan == 2) {
                                        if (chan == 0) {
-                                               snprintf (buf, sizeof(buf), "%s-%u%%L.wav", spath.c_str(), cnt);
+                                               snprintf (buf, sizeof(buf), "%s-%u%%L%s", legalized.c_str(), cnt, ext.c_str());
                                        } else {
-                                               snprintf (buf, sizeof(buf), "%s-%u%%R.wav", spath.c_str(), cnt);
+                                               snprintf (buf, sizeof(buf), "%s-%u%%R%s", legalized.c_str(), cnt, ext.c_str());
                                        }
                                } else if (nchan < 26) {
-                                       snprintf (buf, sizeof(buf), "%s-%u%%%c.wav", spath.c_str(), cnt, 'a' + chan);
+                                       snprintf (buf, sizeof(buf), "%s-%u%%%c%s", legalized.c_str(), cnt, 'a' + chan, ext.c_str());
                                } else {
-                                       snprintf (buf, sizeof(buf), "%s-%u.wav", spath.c_str(), cnt);
+                                       snprintf (buf, sizeof(buf), "%s-%u%s", legalized.c_str(), cnt, ext.c_str());
                                }
                        }
 
-                       if (sys::exists(buf)) {
-                               existing++;
-                       }
+                       SessionDirectory sdir((*i).path);
 
+                       string spath = sdir.sound_path().to_string();
+                       string spath_stubs = sdir.sound_stub_path().to_string();
+
+                        /* note that we search *without* the extension so that
+                           we don't end up both "Audio 1-1.wav" and "Audio 1-1.caf" 
+                           in the event that this new name is required for
+                           a file format change.
+                        */
+
+                        if (matching_unsuffixed_filename_exists_in (spath, buf) ||
+                            matching_unsuffixed_filename_exists_in (spath_stubs, buf)) {
+                                existing++;
+                                break;
+                        }
                }
 
                if (existing == 0) {
@@ -2896,19 +2989,19 @@ Session::new_audio_source_name (const string& base, uint32_t nchan, uint32_t cha
                        throw failed_constructor();
                }
        }
-
-       return Glib::path_get_basename(buf);
+        
+       return Glib::path_get_basename (buf);
 }
 
 /** Create a new within-session audio source */
 boost::shared_ptr<AudioFileSource>
-Session::create_audio_source_for_session (size_t n_chans, string const & n, uint32_t chan, bool destructive)
+Session::create_audio_source_for_session (size_t n_chans, string const & n, uint32_t chan, bool destructive, bool as_stub)
 {
        const string name    = new_audio_source_name (n, n_chans, chan, destructive);
-       const string path    = new_source_path_from_name(DataType::AUDIO, name);
+       const string path    = new_source_path_from_name(DataType::AUDIO, name, as_stub);
 
        return boost::dynamic_pointer_cast<AudioFileSource> (
-               SourceFactory::createWritable (DataType::AUDIO, *this, path, destructive, frame_rate()));
+               SourceFactory::createWritable (DataType::AUDIO, *this, path, string(), destructive, frame_rate()));
 }
 
 /** Return a unique name based on \a base for a new internal MIDI source */
@@ -2962,14 +3055,30 @@ Session::new_midi_source_name (const string& base)
 
 /** Create a new within-session MIDI source */
 boost::shared_ptr<MidiSource>
-Session::create_midi_source_for_session (string const & n)
+Session::create_midi_source_for_session (Track* track, string const & n, bool as_stub)
 {
+        /* try to use the existing write source for the track, to keep numbering sane 
+         */
+
+        if (track) {
+                /*MidiTrack* mt = dynamic_cast<Track*> (track);
+                assert (mt);
+                */
+
+                list<boost::shared_ptr<Source> > l = track->steal_write_sources ();
+                
+                if (!l.empty()) {
+                        assert (boost::dynamic_pointer_cast<MidiSource> (l.front()));
+                        return boost::dynamic_pointer_cast<MidiSource> (l.front());
+                }
+        }
+
        const string name = new_midi_source_name (n);
-       const string path = new_source_path_from_name (DataType::MIDI, name);
+       const string path = new_source_path_from_name (DataType::MIDI, name, as_stub);
 
        return boost::dynamic_pointer_cast<SMFSource> (
                        SourceFactory::createWritable (
-                                       DataType::MIDI, *this, path, false, frame_rate()));
+                                DataType::MIDI, *this, path, string(), false, frame_rate()));
 }
 
 
@@ -3064,42 +3173,6 @@ Session::RoutePublicOrderSorter::operator() (boost::shared_ptr<Route> a, boost::
        return a->order_key(N_("signal")) < b->order_key(N_("signal"));
 }
 
-void
-Session::remove_empty_sounds ()
-{
-       vector<string> audio_filenames;
-
-       get_files_in_directory (_session_dir->sound_path(), audio_filenames);
-
-       Glib::Mutex::Lock lm (source_lock);
-
-       TapeFileMatcher tape_file_matcher;
-
-       remove_if (audio_filenames.begin(), audio_filenames.end(),
-                  boost::bind (&TapeFileMatcher::matches, &tape_file_matcher, _1));
-       
-       for (vector<string>::iterator i = audio_filenames.begin(); i != audio_filenames.end(); ++i) {
-
-               sys::path audio_file_path (_session_dir->sound_path());
-
-               audio_file_path /= *i;
-
-               if (AudioFileSource::is_empty (*this, audio_file_path.to_string())) {
-
-                       try
-                       {
-                               sys::remove (audio_file_path);
-                               const string peakfile = peak_path (audio_file_path.to_string());
-                               sys::remove (peakfile);
-                       }
-                       catch (const sys::filesystem_error& err)
-                       {
-                               error << err.what() << endmsg;
-                       }
-               }
-       }
-}
-
 bool
 Session::is_auditioning () const
 {
@@ -3143,7 +3216,7 @@ Session::graph_reordered ()
        }
 }
 
-nframes_t
+framecnt_t
 Session::available_capture_duration ()
 {
        float sample_bytes_on_disk = 4.0; // keep gcc happy
@@ -3171,11 +3244,11 @@ Session::available_capture_duration ()
 
        double scale = 4096.0 / sample_bytes_on_disk;
 
-       if (_total_free_4k_blocks * scale > (double) max_frames) {
-               return max_frames;
+       if (_total_free_4k_blocks * scale > (double) max_framecnt) {
+               return max_framecnt;
        }
-
-       return (nframes_t) floor (_total_free_4k_blocks * scale);
+        
+       return (framecnt_t) floor (_total_free_4k_blocks * scale);
 }
 
 void
@@ -3236,9 +3309,19 @@ Session::tempo_map_changed (const PropertyChange&)
 
        playlists->update_after_tempo_map_change ();
 
+       _locations->apply (*this, &Session::update_locations_after_tempo_map_change);
+       
        set_dirty ();
 }
 
+void
+Session::update_locations_after_tempo_map_change (Locations::LocationList& loc)
+{
+       for (Locations::LocationList::iterator i = loc.begin(); i != loc.end(); ++i) {
+               (*i)->recompute_frames_from_bbt ();
+       }
+}
+
 /** Ensures that all buffers (scratch, send, silent, etc) are allocated for
  * the given count with the current block size.
  */
@@ -3433,7 +3516,12 @@ Session::reset_native_file_format ()
        for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
                boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
                if (tr) {
+                        /* don't save state as we do this, there's no point
+                         */
+
+                        _state_of_the_state = StateOfTheState (_state_of_the_state|InCleanup);
                        tr->reset_write_sources (false);
+                        _state_of_the_state = StateOfTheState (_state_of_the_state & ~InCleanup);
                }
        }
 }
@@ -3487,7 +3575,7 @@ Session::freeze_all (InterThreadInfo& itt)
 }
 
 boost::shared_ptr<Region>
-Session::write_one_track (AudioTrack& track, nframes_t start, nframes_t end,
+Session::write_one_track (AudioTrack& track, framepos_t start, framepos_t end,
                          bool /*overwrite*/, vector<boost::shared_ptr<Source> >& srcs,
                          InterThreadInfo& itt, bool enable_processing)
 {
@@ -3497,13 +3585,15 @@ Session::write_one_track (AudioTrack& track, nframes_t start, nframes_t end,
        uint32_t x;
        char buf[PATH_MAX+1];
        ChanCount nchans(track.n_channels());
-       nframes_t position;
-       nframes_t this_chunk;
-       nframes_t to_do;
+       framepos_t position;
+       framecnt_t this_chunk;
+       framepos_t to_do;
        BufferSet buffers;
        SessionDirectory sdir(get_best_session_directory_for_new_source ());
        const string sound_dir = sdir.sound_path().to_string();
-       nframes_t len = end - start;
+       framepos_t len = end - start;
+        bool need_block_size_reset = false;
+        string ext;
 
        if (end <= start) {
                error << string_compose (_("Cannot write a range where end <= start (e.g. %1 <= %2)"),
@@ -3511,7 +3601,7 @@ Session::write_one_track (AudioTrack& track, nframes_t start, nframes_t end,
                return result;
        }
 
-       const nframes_t chunk_size = (256 * 1024)/4;
+       const framecnt_t chunk_size = (256 * 1024)/4;
 
        // block all process callback handling
 
@@ -3529,10 +3619,12 @@ Session::write_one_track (AudioTrack& track, nframes_t start, nframes_t end,
                goto out;
        }
 
+        ext = native_header_format_extension (config.get_native_file_header_format(), DataType::AUDIO);
+
        for (uint32_t chan_n=0; chan_n < nchans.n_audio(); ++chan_n) {
 
                for (x = 0; x < 99999; ++x) {
-                       snprintf (buf, sizeof(buf), "%s/%s-%d-bounce-%" PRIu32 ".wav", sound_dir.c_str(), playlist->name().c_str(), chan_n, x+1);
+                       snprintf (buf, sizeof(buf), "%s/%s-%d-bounce-%" PRIu32 "%s", sound_dir.c_str(), playlist->name().c_str(), chan_n, x+1, ext.c_str());
                        if (access (buf, F_OK) != 0) {
                                break;
                        }
@@ -3545,7 +3637,7 @@ Session::write_one_track (AudioTrack& track, nframes_t start, nframes_t end,
 
                try {
                        fsource = boost::dynamic_pointer_cast<AudioFileSource> (
-                               SourceFactory::createWritable (DataType::AUDIO, *this, buf, false, frame_rate()));
+                               SourceFactory::createWritable (DataType::AUDIO, *this, buf, string(), false, frame_rate()));
                }
 
                catch (failed_constructor& err) {
@@ -3556,6 +3648,11 @@ Session::write_one_track (AudioTrack& track, nframes_t start, nframes_t end,
                srcs.push_back (fsource);
        }
 
+        /* tell redirects that care that we are about to use a much larger blocksize */
+        
+        need_block_size_reset = true;
+        track.set_block_size (chunk_size);
+
        /* XXX need to flush all redirects */
 
        position = start;
@@ -3646,6 +3743,11 @@ Session::write_one_track (AudioTrack& track, nframes_t start, nframes_t end,
                }
        }
 
+
+        if (need_block_size_reset) {
+                track.set_block_size (get_block_size());
+        }
+        
        unblock_processing ();
 
        return result;
@@ -3744,12 +3846,6 @@ Session::add_automation_list(AutomationList *al)
        automation_lists[al->id()] = al;
 }
 
-nframes_t
-Session::compute_initial_length ()
-{
-       return _engine.frame_rate() * 60 * 5;
-}
-
 void
 Session::sync_order_keys (std::string const & base)
 {
@@ -3841,6 +3937,7 @@ Session::solo_control_mode_changed ()
         }
 }
 
+/** Called when anything about any of our route groups changes (membership, state etc.) */
 void
 Session::route_group_changed ()
 {
@@ -3853,20 +3950,14 @@ Session::get_available_sync_options () const
        vector<SyncSource> ret;
        
        ret.push_back (JACK);
-
-       if (mtc_port()) {
-               ret.push_back (MTC);
-       } 
-
-       if (midi_clock_port()) {
-               ret.push_back (MIDIClock);
-       } 
+       ret.push_back (MTC);
+       ret.push_back (MIDIClock);
 
        return ret;
 }
 
 boost::shared_ptr<RouteList>
-Session::get_routes_with_regions_at (nframes64_t const p) const
+Session::get_routes_with_regions_at (framepos_t const p) const
 {
        shared_ptr<RouteList> r = routes.reader ();
        shared_ptr<RouteList> rl (new RouteList);
@@ -3889,3 +3980,211 @@ Session::get_routes_with_regions_at (nframes64_t const p) const
 
        return rl;
 }
+
+void
+Session::goto_end ()
+{
+       if (_session_range_location) {
+               request_locate (_session_range_location->end(), false);
+       } else {
+               request_locate (0, false);
+       }
+}
+
+void
+Session::goto_start ()
+{
+       if (_session_range_location) {
+               request_locate (_session_range_location->start(), false);
+       } else {
+               request_locate (0, false);
+       }
+}
+
+framepos_t
+Session::current_start_frame () const
+{
+       return _session_range_location ? _session_range_location->start() : 0;
+}
+
+framepos_t
+Session::current_end_frame () const
+{
+       return _session_range_location ? _session_range_location->end() : 0;
+}
+
+void
+Session::add_session_range_location (nframes_t start, nframes_t end)
+{
+       _session_range_location = new Location (*this, start, end, _("session"), Location::IsSessionRange);
+       _locations->add (_session_range_location);
+}
+
+/** Called when one of our routes' order keys has changed */
+void
+Session::route_order_key_changed ()
+{
+       RouteOrderKeyChanged (); /* EMIT SIGNAL */
+}
+
+void
+Session::step_edit_status_change (bool yn)
+{
+        bool send = false;
+
+        bool val = false;
+        if (yn) {
+                send = (_step_editors == 0);
+                val = true;
+
+                _step_editors++;
+        } else {
+                send = (_step_editors == 1);
+                val = false;
+
+                if (_step_editors > 0) {
+                        _step_editors--;
+                }
+        }
+
+        if (send) {
+                StepEditStatusChange (val);
+        }
+}
+
+        
+void
+Session::start_time_changed (framepos_t old)
+{
+       /* Update the auto loop range to match the session range
+          (unless the auto loop range has been changed by the user)
+       */
+       
+       Location* s = _locations->session_range_location ();
+       Location* l = _locations->auto_loop_location ();
+
+       if (l->start() == old) {
+               l->set_start (s->start(), true);
+       }
+}
+
+void
+Session::end_time_changed (framepos_t old)
+{
+       /* Update the auto loop range to match the session range
+          (unless the auto loop range has been changed by the user)
+       */
+
+       Location* s = _locations->session_range_location ();
+       Location* l = _locations->auto_loop_location ();
+
+       if (l->end() == old) {
+               l->set_end (s->end(), true);
+       }
+}
+
+string
+Session::source_search_path (DataType type) const
+{
+        string search_path;
+
+       if (session_dirs.size() == 1) {
+                switch (type) {
+                case DataType::AUDIO:
+                        search_path = _session_dir->sound_path().to_string();
+                        break;
+                case DataType::MIDI:
+                        search_path = _session_dir->midi_path().to_string();
+                        break;
+                }
+       } else {
+                for (vector<space_and_path>::const_iterator i = session_dirs.begin(); i != session_dirs.end(); ++i) {
+                        SessionDirectory sdir (i->path);
+                        if (!search_path.empty()) {
+                                search_path += ':';
+                        } 
+                        switch (type) {
+                        case DataType::AUDIO:
+                                search_path += sdir.sound_path().to_string();
+                                break;
+                        case DataType::MIDI:
+                                search_path += sdir.midi_path().to_string();
+                                break;
+                        }
+                }
+        }
+                
+        /* now add user-specified locations
+         */
+
+        vector<string> dirs;
+
+        switch (type) {
+        case DataType::AUDIO:
+                split (config.get_audio_search_path (), dirs, ':');
+                break;
+        case DataType::MIDI:
+                split (config.get_midi_search_path (), dirs, ':');
+                break;
+        }
+
+        for (vector<string>::iterator i = dirs.begin(); i != dirs.end(); ++i) {
+                        search_path += ':';
+                        search_path += *i;
+                        
+        }
+        
+        return search_path;
+}
+
+void
+Session::ensure_search_path_includes (const string& path, DataType type)
+{
+        string search_path;
+        vector<string> dirs;
+
+        if (path == ".") {
+                return;
+        }
+
+        switch (type) {
+        case DataType::AUDIO:
+                search_path = config.get_audio_search_path ();
+                break;
+        case DataType::MIDI:
+                search_path = config.get_midi_search_path ();
+                break;
+        }
+
+        split (search_path, dirs, ':');
+
+        for (vector<string>::iterator i = dirs.begin(); i != dirs.end(); ++i) {
+                if (*i == path) {
+                        return;
+                }
+        }
+
+        if (!search_path.empty()) {
+                search_path += ':';
+        }
+
+        search_path += path;
+        
+        switch (type) {
+        case DataType::AUDIO:
+                config.set_audio_search_path (search_path);
+                break;
+        case DataType::MIDI:
+                config.set_midi_search_path (search_path);
+                break;
+        }
+}
+
+VBAPSpeakers&
+Session::get_speakers() 
+{
+        if (!_speakers) {
+                _speakers = new VBAPSpeakers;
+        }
+        return *_speakers;
+}