major design changes: use glib event loop for MIDI thread/UI; rework design of BaseUI and AbstractUI; solo & mute are both temporarily broken; OSC control up next; may segfault during exit

git-svn-id: svn://localhost/ardour2/branches/3.0@6328 d708f5d6-7413-0410-9779-e7cbd77b26cf

13 files changed, 238 insertions, 548 deletions

diff --git a/libs/ardour/analyser.cc b/libs/ardour/analyser.cc
index 8e2ec99f27..992e5c5246 100644
--- a/libs/ardour/analyser.cc
+++ b/libs/ardour/analyser.cc
@@ -76,7 +76,6 @@ Analyser::queue_source_for_analysis (boost::shared_ptr<Source> src, bool force)
 void
 Analyser::work ()
 {
-	PBD::notify_gui_about_thread_creation (pthread_self(), string ("analyser-") + to_string (pthread_self(), std::dec));
 	SessionEvent::create_per_thread_pool ("Analyser", 64);
 
 	while (true) {
diff --git a/libs/ardour/ardour/midi_ui.h b/libs/ardour/ardour/midi_ui.h
new file mode 100644
index 0000000000..e1f322ddd1
--- /dev/null
+++ b/libs/ardour/ardour/midi_ui.h
@@ -0,0 +1,52 @@
+#ifndef __libardour_midi_ui_h__
+#define __libardour_midi_ui_h__
+
+#include <list>
+#include "pbd/abstract_ui.h"
+
+namespace MIDI { 
+	class port;
+}
+
+namespace ARDOUR {
+
+class Session;
+
+/* this is mostly a placeholder because I suspect that at some
+   point we will want to add more members to accomodate
+   certain types of requests to the MIDI UI
+*/
+
+struct MidiUIRequest : public BaseUI::BaseRequestObject {
+  public:
+	MidiUIRequest () {}
+	~MidiUIRequest() {}
+};
+
+class MidiControlUI : public AbstractUI<MidiUIRequest>
+{
+  public:
+	MidiControlUI (Session& s);
+	~MidiControlUI ();
+	
+	static BaseUI::RequestType PortChange;
+	
+	void change_midi_ports ();
+	
+  protected:
+	void thread_init ();
+	void do_request (MidiUIRequest*);
+	
+  private:
+	typedef std::list<Glib::RefPtr<Glib::IOSource> > PortSources;
+	PortSources port_sources;
+	ARDOUR::Session& _session;
+	
+	bool midi_input_handler (Glib::IOCondition, MIDI::Port*);
+	void reset_ports ();
+	void clear_ports ();
+};
+
+}
+
+#endif /* __libardour_midi_ui_h__ */
diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index ed34c387e8..4e1721bae0 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -97,6 +97,7 @@ class MidiDiskstream;
 class MidiRegion;
 class MidiSource;
 class MidiTrack;
+class MidiControlUI;
 class NamedSelection;
 class Playlist;
 class PluginInsert;
@@ -616,14 +617,14 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	bool soloing() const { return _non_soloed_outs_muted; }
 	bool listening() const { return _listen_cnt > 0; }
 
-	void set_all_solo (bool);
-	void set_all_mute (bool);
-	void set_all_listen (bool);
+	void set_solo (boost::shared_ptr<RouteList>, bool);
+	void set_mute (boost::shared_ptr<RouteList>, bool);
+	void set_listen (boost::shared_ptr<RouteList>, bool);
 
 	sigc::signal<void,bool> SoloActive;
 	sigc::signal<void> SoloChanged;
 	
-	void set_all_record_enable (boost::shared_ptr<RouteList>, bool);
+	void set_record_enable (boost::shared_ptr<RouteList>, bool);
 
 	/* control/master out */
 
@@ -1253,25 +1254,11 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	bool non_realtime_work_pending() const { return static_cast<bool>(post_transport_work()); }
 	bool process_can_proceed() const { return !(post_transport_work() & ProcessCannotProceedMask); }
 
-	struct MIDIRequest {
-		enum Type {
-			PortChange,
-			Quit
-		};
-		Type type;
-	};
-
-	Glib::Mutex  midi_lock;
-	pthread_t    midi_thread;
-	int          midi_request_pipe[2];
-	RingBuffer<MIDIRequest*> midi_requests;
+	MidiControlUI* midi_control_ui;
 
 	int           start_midi_thread ();
 	void          terminate_midi_thread ();
-	void          poke_midi_thread ();
-	static void *_midi_thread_work (void *arg);
-	void          midi_thread_work ();
-	void          change_midi_ports ();
+
 	int           use_config_midi_ports ();
 
 	void set_play_loop (bool yn);
diff --git a/libs/ardour/audioengine.cc b/libs/ardour/audioengine.cc
index b69b06c4db..2c16c52296 100644
--- a/libs/ardour/audioengine.cc
+++ b/libs/ardour/audioengine.cc
@@ -135,7 +135,9 @@ _thread_init_callback (void * /*arg*/)
 	   knows about it.
 	*/
 
-	PBD::notify_gui_about_thread_creation (pthread_self(), X_("Audioengine"), 4096);
+	PBD::notify_gui_about_thread_creation ("gui", pthread_self(), X_("Audioengine"), 4096);
+	PBD::notify_gui_about_thread_creation ("midiui", pthread_self(), X_("Audioengine"), 128);
+
 	SessionEvent::create_per_thread_pool (X_("Audioengine"), 512);
 
 	MIDI::JACK_MidiPort::set_process_thread (pthread_self());
diff --git a/libs/ardour/butler.cc b/libs/ardour/butler.cc
index 76a7fb2424..05ac7316ec 100644
--- a/libs/ardour/butler.cc
+++ b/libs/ardour/butler.cc
@@ -89,7 +89,7 @@ Butler::start_thread()
 		return -1;
 	}
 
-	if (pthread_create_and_store ("disk butler", &thread, 0, _thread_work, this)) {
+	if (pthread_create_and_store ("disk butler", &thread, _thread_work, this)) {
 		error << _("Session: could not create butler thread") << endmsg;
 		return -1;
 	}
@@ -113,7 +113,6 @@ Butler::terminate_thread ()
 void *
 Butler::_thread_work (void* arg)
 {
-	PBD::notify_gui_about_thread_creation (pthread_self(), X_("Butler"));
 	SessionEvent::create_per_thread_pool ("butler events", 64);
 	return ((Butler *) arg)->thread_work ();
 }
diff --git a/libs/ardour/export_channel_configuration.cc b/libs/ardour/export_channel_configuration.cc
index 047aadc671..89a4952feb 100644
--- a/libs/ardour/export_channel_configuration.cc
+++ b/libs/ardour/export_channel_configuration.cc
@@ -176,7 +176,6 @@ ExportChannelConfiguration::write_file ()
 void *
 ExportChannelConfiguration::_write_files (void *arg)
 {
-	notify_gui_about_thread_creation (pthread_self(), "Export post-processing");
 	SessionEvent::create_per_thread_pool ("exporter events", 64);
 
 	// cc can be trated like 'this'
diff --git a/libs/ardour/midi_ui.cc b/libs/ardour/midi_ui.cc
new file mode 100644
index 0000000000..5a0640b3f6
--- /dev/null
+++ b/libs/ardour/midi_ui.cc
@@ -0,0 +1,150 @@
+/*
+  Copyright (C) 2009 Paul Davis
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+#include <cstdlib>
+
+#include "pbd/pthread_utils.h"
+
+#include "midi++/manager.h"
+#include "midi++/port.h"
+
+#include "ardour/debug.h"
+#include "ardour/audioengine.h"
+#include "ardour/midi_ui.h"
+#include "ardour/session.h"
+#include "ardour/session_event.h"
+#include "ardour/types.h"
+
+using namespace std;
+using namespace ARDOUR;
+using namespace Glib;
+
+#include "i18n.h"
+
+BaseUI::RequestType MidiControlUI::PortChange = BaseUI::new_request_type();
+
+#include "pbd/abstract_ui.cc"  /* instantiate the template */
+
+MidiControlUI::MidiControlUI (Session& s)
+	: AbstractUI<MidiUIRequest> (_("midiui"))
+	, _session (s) 
+{
+	MIDI::Manager::instance()->PortsChanged.connect (mem_fun (*this, &MidiControlUI::change_midi_ports));
+}
+
+MidiControlUI::~MidiControlUI ()
+{
+	clear_ports ();
+}
+
+void
+MidiControlUI::do_request (MidiUIRequest* req)
+{
+	if (req->type == PortChange) {
+
+		/* restart event loop with new ports */
+		DEBUG_TRACE (DEBUG::MidiIO, "reset ports\n");
+		reset_ports ();
+
+	} else if (req->type == CallSlot) {
+
+		req->the_slot ();
+	}
+}
+
+void
+MidiControlUI::change_midi_ports ()
+{
+	MidiUIRequest* req = get_request (PortChange);
+	if (req == 0) {
+		return;
+	}
+	send_request (req);
+}
+
+bool
+MidiControlUI::midi_input_handler (IOCondition ioc, MIDI::Port* port)
+{
+	if (ioc & ~IO_IN) {
+		return false;
+	}
+
+	if (ioc & IO_IN) {
+
+		if (port->must_drain_selectable()) {
+			CrossThreadChannel::drain (port->selectable());
+		}
+
+		DEBUG_TRACE (DEBUG::MidiIO, string_compose ("data available on %1\n", port->name()));
+		nframes64_t now = _session.engine().frame_time();
+		port->parse (now);
+	}
+
+	return true;
+}
+
+void
+MidiControlUI::clear_ports ()
+{
+	for (PortSources::iterator i = port_sources.begin(); i != port_sources.end(); ++i) {
+		/* remove existing sources from the event loop */
+		(*i)->destroy ();
+	}
+
+	port_sources.clear ();
+}
+
+void
+MidiControlUI::reset_ports ()
+{
+	clear_ports ();
+
+	MIDI::Manager::PortList plist = MIDI::Manager::instance()->get_midi_ports ();
+
+	for (MIDI::Manager::PortList::iterator i = plist.begin(); i != plist.end(); ++i) {
+		int fd;
+		if ((fd = (*i)->selectable ()) >= 0) {
+			Glib::RefPtr<IOSource> psrc = IOSource::create (fd, IO_IN|IO_HUP|IO_ERR);
+			psrc->connect (bind (mem_fun (*this, &MidiControlUI::midi_input_handler), (*i)));
+			port_sources.push_back (psrc);
+		} 
+	}
+
+	for (PortSources::iterator i = port_sources.begin(); i != port_sources.end(); ++i) {
+		(*i)->attach (_main_loop->get_context());
+	}
+}
+
+void
+MidiControlUI::thread_init ()
+{	
+	struct sched_param rtparam;
+
+	PBD::notify_gui_about_thread_creation (X_("gui"), pthread_self(), X_("MIDI"), 2048);
+	SessionEvent::create_per_thread_pool (X_("MIDI I/O"), 128);
+
+	memset (&rtparam, 0, sizeof (rtparam));
+	rtparam.sched_priority = 9; /* XXX should be relative to audio (JACK) thread */
+
+	if (pthread_setschedparam (pthread_self(), SCHED_FIFO, &rtparam) != 0) {
+		// do we care? not particularly.
+	}
+
+	reset_ports ();
+}
+
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index cdd5041856..9c3b28049f 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -71,6 +71,7 @@
 #include "ardour/midi_playlist.h"
 #include "ardour/midi_region.h"
 #include "ardour/midi_track.h"
+#include "ardour/midi_ui.h"
 #include "ardour/named_selection.h"
 #include "ardour/playlist.h"
 #include "ardour/plugin_insert.h"
@@ -137,8 +138,6 @@ Session::Session (AudioEngine &eng,
 	  _butler (new Butler (this)),
 	  _post_transport_work (0),
 	  _send_timecode_update (false),
-	  midi_thread (pthread_t (0)),
-	  midi_requests (128), // the size of this should match the midi request pool size
 	  diskstreams (new DiskstreamList),
 	  routes (new RouteList),
 	  _total_free_4k_blocks (0),
@@ -224,8 +223,6 @@ Session::Session (AudioEngine &eng,
 	  _butler (new Butler (this)),
 	  _post_transport_work (0),
 	  _send_timecode_update (false),
-	  midi_thread (pthread_t (0)),
-	  midi_requests (16),
 	  diskstreams (new DiskstreamList),
 	  routes (new RouteList),
 	  _total_free_4k_blocks (0),
@@ -366,7 +363,8 @@ Session::destroy ()
 	Stateful::loading_state_version = 0;
 
 	_butler->terminate_thread ();
-	//terminate_midi_thread ();
+	
+	delete midi_control_ui;
 
 	if (click_data != default_click) {
 		delete [] click_data;
@@ -3518,10 +3516,8 @@ Session::is_auditioning () const
 }
 
 void
-Session::set_all_solo (bool yn)
+Session::set_solo (boost::shared_ptr<RouteList> r, bool yn)
 {
-	shared_ptr<RouteList> r = routes.reader ();
-
 	for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 		if (!(*i)->is_hidden()) {
 			(*i)->set_solo (yn, this);
@@ -3532,10 +3528,8 @@ Session::set_all_solo (bool yn)
 }
 
 void
-Session::set_all_listen (bool yn)
+Session::set_listen (boost::shared_ptr<RouteList> r, bool yn)
 {
-	shared_ptr<RouteList> r = routes.reader ();
-
 	for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 		if (!(*i)->is_hidden()) {
 			(*i)->set_listen (yn, this);
@@ -3546,10 +3540,8 @@ Session::set_all_listen (bool yn)
 }
 
 void
-Session::set_all_mute (bool yn)
+Session::set_mute (boost::shared_ptr<RouteList> r, bool yn)
 {
-	shared_ptr<RouteList> r = routes.reader ();
-
 	for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 		if (!(*i)->is_hidden()) {
 			(*i)->set_mute (yn, this);
@@ -3605,7 +3597,7 @@ Session::graph_reordered ()
 }
 
 void
-Session::set_all_record_enable (boost::shared_ptr<RouteList> rl, bool yn)
+Session::set_record_enable (boost::shared_ptr<RouteList> rl, bool yn)
 {
 	if (!writable()) {
 		return;
@@ -4037,8 +4029,7 @@ Session::write_one_track (AudioTrack& track, nframes_t start, nframes_t end,
 		return result;
 	}
 
-	// any bigger than this seems to cause stack overflows in called functions
-	const nframes_t chunk_size = (128 * 1024)/4;
+	const nframes_t chunk_size = (256 * 1024)/4;
 
 	// block all process callback handling
 
@@ -4323,9 +4314,9 @@ Session::solo_control_mode_changed ()
 	/* cancel all solo or all listen when solo control mode changes */
 
 	if (Config->get_solo_control_is_listen_control()) {
-		set_all_solo (false);
+		set_solo (routes.reader(), false);
 	} else {
-		set_all_listen (false);
+		set_listen (routes.reader(), false);
 	}
 }
 
diff --git a/libs/ardour/session_midi.cc b/libs/ardour/session_midi.cc
index a0366dd6e8..4388fe6dca 100644
--- a/libs/ardour/session_midi.cc
+++ b/libs/ardour/session_midi.cc
@@ -28,6 +28,7 @@
 
 #include <boost/shared_ptr.hpp>
 
+#include <glibmm/main.h>
 
 #include "midi++/mmc.h"
 #include "midi++/port.h"
@@ -41,6 +42,7 @@
 #include "ardour/session.h"
 #include "ardour/audio_track.h"
 #include "ardour/midi_track.h"
+#include "ardour/midi_ui.h"
 #include "ardour/audio_diskstream.h"
 #include "ardour/slave.h"
 #include "ardour/cycles.h"
@@ -52,6 +54,7 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 using namespace MIDI;
+using namespace Glib;
 
 MachineControl::CommandSignature MMC_CommandSignature;
 MachineControl::ResponseSignature MMC_ResponseSignature;
@@ -146,7 +149,6 @@ Session::set_mtc_port (string port_tag)
 
   out:
 	MTC_PortChanged(); /* EMIT SIGNAL */
-	change_midi_ports ();
 	set_dirty();
 	return 0;
 }
@@ -244,7 +246,6 @@ Session::set_mmc_port (string port_tag)
 
   out:
 	MMC_PortChanged(); /* EMIT SIGNAL */
-	change_midi_ports ();
 	set_dirty();
 	return 0;
 }
@@ -278,7 +279,6 @@ Session::set_midi_port (string /*port_tag*/)
   out:
 #endif
 	MIDI_PortChanged(); /* EMIT SIGNAL */
-	change_midi_ports ();
 	set_dirty();
 	return 0;
 }
@@ -320,7 +320,6 @@ Session::set_midi_clock_port (string port_tag)
 
   out:
 	MIDIClock_PortChanged(); /* EMIT SIGNAL */
-	change_midi_ports ();
 	set_dirty();
 	return 0;
 }
@@ -640,8 +639,12 @@ Session::mmc_step (MIDI::MachineControl &/*mmc*/, int steps)
 	last_mmc_step = now;
 
 	if (!step_queued) {
-		midi_timeouts.push_back (mem_fun (*this, &Session::mmc_step_timeout));
-		step_queued = true;
+		if (midi_control_ui) {
+			RefPtr<TimeoutSource> tsrc = TimeoutSource::create (100);
+			tsrc->connect (mem_fun (*this, &Session::mmc_step_timeout));
+			tsrc->attach (midi_control_ui->main_loop()->get_context());
+			step_queued = true;
+		}
 	}
 }
 
@@ -741,16 +744,6 @@ Session::mmc_record_enable (MIDI::MachineControl &mmc, size_t trk, bool enabled)
 	}
 }
 
-void
-Session::change_midi_ports ()
-{
-	MIDIRequest* request = new MIDIRequest;
-
-	request->type = MIDIRequest::PortChange;
-	midi_requests.write (&request, 1);
-	poke_midi_thread ();
-}
-
 /** Send MTC Full Frame message (complete Timecode time) for the start of this cycle.
  * This resets the MTC code, the next quarter frame message that is sent will be
  * the first one with the beginning of this cycle as the new start point.
@@ -1022,495 +1015,17 @@ Session::mmc_step_timeout ()
 int
 Session::start_midi_thread ()
 {
-	if (pipe (midi_request_pipe)) {
-		error << string_compose(_("Cannot create transport request signal pipe (%1)"), strerror (errno)) << endmsg;
-		return -1;
-	}
-
-	if (fcntl (midi_request_pipe[0], F_SETFL, O_NONBLOCK)) {
-		error << string_compose(_("UI: cannot set O_NONBLOCK on "    "signal read pipe (%1)"), strerror (errno)) << endmsg;
-		return -1;
-	}
-
-	if (fcntl (midi_request_pipe[1], F_SETFL, O_NONBLOCK)) {
-		error << string_compose(_("UI: cannot set O_NONBLOCK on "    "signal write pipe (%1)"), strerror (errno)) << endmsg;
-		return -1;
-	}
-
-	if (pthread_create_and_store ("transport", &midi_thread, 0, _midi_thread_work, this)) {
-		error << _("Session: could not create transport thread") << endmsg;
-		return -1;
-	}
-
+	midi_control_ui = new MidiControlUI (*this);
+	midi_control_ui->run ();
 	return 0;
 }
 
 void
 Session::terminate_midi_thread ()
 {
-	if (midi_thread) {
-
-		MIDIRequest* request = new MIDIRequest;
-		void* status;
-
-		request->type = MIDIRequest::Quit;
-
-		midi_requests.write (&request, 1);
-		poke_midi_thread ();
-
-		pthread_join (midi_thread, &status);
-	}
-}
-
-void
-Session::poke_midi_thread ()
-{
-	static char c = 0;
-
-	if (write (midi_request_pipe[1], &c, 1) != 1) {
-		error << string_compose(_("cannot send signal to midi thread! (%1)"), strerror (errno)) << endmsg;
-	}
-}
-
-void *
-Session::_midi_thread_work (void* arg)
-{
-	pthread_setcancelstate (PTHREAD_CANCEL_ENABLE, 0);
-	pthread_setcanceltype (PTHREAD_CANCEL_ASYNCHRONOUS, 0);
-
-	((Session *) arg)->midi_thread_work ();
-	return 0;
-}
-
-#if 0
-void
-Session::midi_thread_work ()
-{
-	MIDIRequest* request;
-	GPollFD pfd[4];
-	int nfds = 0;
-	int timeout;
-	int fds_ready;
-	struct sched_param rtparam;
-	int x;
-	bool restart;
-	vector<MIDI::Port*> ports;
-
-	PBD::notify_gui_about_thread_creation (pthread_self(), X_("MIDI"), 2048);
-	SessionEvent::create_per_thread_pool (X_("MIDI I/O"), 128);
-
-	memset (&rtparam, 0, sizeof (rtparam));
-	rtparam.sched_priority = 9; /* XXX should be relative to audio (JACK) thread */
-
-	if ((x = pthread_setschedparam (pthread_self(), SCHED_FIFO, &rtparam)) != 0) {
-		// do we care? not particularly.
-	}
-
-	/* set up the port vector; 5 is the largest possible size for now */
-
-	ports.assign (5, (MIDI::Port*) 0);
-
-	GMainContext* main_context = g_main_context_new ();
-
-	while (1) {
-
-		nfds = 0;
-
-		gpfd[nfds].fd = midi_request_pipe[0];
-		gpfd[nfds].events = POLLIN|POLLHUP|POLLERR;
-		nfds++;
-
-		if (Config->get_mmc_control() && _mmc_port && _mmc_port->selectable() >= 0) {
-			gpfd[nfds].fd = _mmc_port->selectable();
-			gpfd[nfds].events = POLLIN|POLLHUP|POLLERR;
-			ports[nfds] = _mmc_port;
-			g_main_context_add_poll (&gpfd[nfds]);
-			DEBUG_TRACE (DEBUG::MidiIO, string_compose ("set up port #%1 for mmc @ %2\n", nfds, _mmc_port));
-			nfds++;
-		}
-
-		/* if MTC is being handled on a different port from MMC
-		   or we are not handling MMC at all, poll
-		   the relevant port.
-		*/
-
-		if (_mtc_port && (_mtc_port != _mmc_port || !Config->get_mmc_control()) && _mtc_port->selectable() >= 0) {
-			gpfd[nfds].fd = _mtc_port->selectable();
-			gpfd[nfds].events = POLLIN|POLLHUP|POLLERR;
-			ports[nfds] = _mtc_port;
-			g_main_context_add_poll (&gpfd[nfds]);
-			DEBUG_TRACE (DEBUG::MidiIO, string_compose ("set up port #%1 for mtc @ %2\n", nfds, _mtc_port));
-			nfds++;
-		}
-
-		if (_midi_clock_port && (_midi_clock_port != _mmc_port || !Config->get_mmc_control()) && _midi_clock_port->selectable() >= 0) {
-			gpfd[nfds].fd = _midi_clock_port->selectable();
-			gpfd[nfds].events = POLLIN|POLLHUP|POLLERR;
-			ports[nfds] = _midi_clock_port;
-			g_main_context_add_poll (&gpfd[nfds]);
-			DEBUG_TRACE (DEBUG::MidiIO, string_compose ("set up port #%1 for midi clock @ %2\n", nfds, _midi_clock_port));
-			nfds++;
-		}
-
-		/* if we are using MMC control, we obviously have to listen
-		   the relevant port.
-		*/
-
-		if (_midi_port && (_midi_port != _mmc_port || !Config->get_mmc_control()) && (_midi_port != _mtc_port) && _midi_port->selectable() >= 0) {
-			gpfd[nfds].fd = _midi_port->selectable();
-			gpfd[nfds].events = POLLIN|POLLHUP|POLLERR;
-			ports[nfds] = _midi_port;
-			g_main_context_add_poll (&gpfd[nfds]);
-			DEBUG_TRACE (DEBUG::MidiIO, string_compose ("set up port #%1 for midi @ %2\n", nfds, _midi_port));
-			nfds++;
-		}
-
-		if (!midi_timeouts.empty()) {
-			timeout = 100; /* 10msecs */
-		} else {
-			timeout = -1; /* if there is no data, we don't care */
-		}
-
-	  again:
-
-		DEBUG_TRACE (DEBUG::MidiIO, string_compose ("MIDI poll on %1 fds for %2\n", nfds, timeout));
-		if (g_poll (gpfd, nfds, timeout) < 0) {
-			if (errno == EINTR) {
-				/* gdb at work, perhaps */
-				goto again;
-			}
-
-			error << string_compose(_("MIDI thread poll failed (%1)"), strerror (errno)) << endmsg;
-
-			break;
-		}
-
-		nframes64_t now = engine().frame_time();
-
-		DEBUG_TRACE (DEBUG::MidiIO, "MIDI thread awake\n");
-
-		fds_ready = 0;
-
-		/* check the transport request pipe */
-
-		if (gpfd[0].revents & ~POLLIN) {
-			error << _("Error on transport thread request pipe") << endmsg;
-			break;
-		}
-
-		if (gpfd[0].revents & POLLIN) {
-
-			char foo[16];
-			
-			DEBUG_TRACE (DEBUG::MidiIO, "MIDI request FIFO ready\n");
-			fds_ready++;
-
-			/* empty the pipe of all current requests */
-
-			while (1) {
-				size_t nread = read (midi_request_pipe[0], &foo, sizeof (foo));
-
-				if (nread > 0) {
-					if ((size_t) nread < sizeof (foo)) {
-						break;
-					} else {
-						continue;
-					}
-				} else if (nread == 0) {
-					break;
-				} else if (errno == EAGAIN) {
-					break;
-				} else {
-					fatal << _("Error reading from transport request pipe") << endmsg;
-					/*NOTREACHED*/
-				}
-			}
-
-			while (midi_requests.read (&request, 1) == 1) {
-
-				switch (request->type) {
-				case MIDIRequest::PortChange:
-					/* restart poll with new ports */
-					DEBUG_TRACE (DEBUG::MidiIO, "rebind\n");
-					restart = true;
-					break;
-
-				case MIDIRequest::Quit:
-					delete request;
-					DEBUG_TRACE (DEBUG::MidiIO, "thread quit\n");
-					pthread_exit_pbd (0);
-					/*NOTREACHED*/
-					break;
-
-				default:
-					break;
-				}
-
-
-				delete request;
-			}
-
-		}
-
-		if (restart) {
-			DEBUG_TRACE (DEBUG::MidiIO, "ports changed, restart poll\n");
-			restart = false;
-			continue;
-		}
-
-		/* now read the rest of the ports */
-
-		for (int p = 1; p < nfds; ++p) {
-
-			DEBUG_STR_SET(foo, "port #%1 revents = ");
-			DEBUG_STR(foo) << hex << pfd[p].revents << dec << endl;
-			DEBUG_TRACE (DEBUG::MidiIO, string_compose (DEBUG_STR(foo).str(), p));
-
-			if ((pfd[p].revents & ~POLLIN)) {
-				// error << string_compose(_("Transport: error polling MIDI port %1 (revents =%2%3%4"), p, &hex, pfd[p].revents, &dec) << endmsg;
-				break;
-			}
-
-			if (pfd[p].revents & POLLIN) {
-				DEBUG_TRACE (DEBUG::MidiIO, string_compose ("MIDI fd # %1 has data ready @ %2\n", p, now));
-				fds_ready++;
-				ports[p]->parse (now);
-			}
-
-			g_main_context_remove_poll (&gpfd[p]);
-		}
-
-		/* timeout driven */
-
-		if (fds_ready < 2 && timeout != -1) {
-
-			DEBUG_TRACE (DEBUG::MidiIO, "Check timeouts\n");
-			for (MidiTimeoutList::iterator i = midi_timeouts.begin(); i != midi_timeouts.end(); ) {
-
-				MidiTimeoutList::iterator tmp;
-				tmp = i;
-				++tmp;
-
-				if (!(*i)()) {
-					midi_timeouts.erase (i);
-				}
-
-				i = tmp;
-			}
-		}
+	if (midi_control_ui) {
+		midi_control_ui->quit ();
 	}
-
 }
-#endif
-
-void
-Session::midi_thread_work ()
-{
-	MIDIRequest* request;
-	struct pollfd pfd[4];
-	int nfds = 0;
-	int timeout;
-	int fds_ready;
-	struct sched_param rtparam;
-	int x;
-	bool restart;
-	vector<MIDI::Port*> ports;
-
-	PBD::notify_gui_about_thread_creation (pthread_self(), X_("MIDI"), 2048);
-	SessionEvent::create_per_thread_pool (X_("MIDI I/O"), 128);
-
-	memset (&rtparam, 0, sizeof (rtparam));
-	rtparam.sched_priority = 9; /* XXX should be relative to audio (JACK) thread */
-
-	if ((x = pthread_setschedparam (pthread_self(), SCHED_FIFO, &rtparam)) != 0) {
-		// do we care? not particularly.
-	}
-
-	/* set up the port vector; 5 is the largest possible size for now */
-
-	ports.assign (5, (MIDI::Port*) 0);
-
-	while (1) {
-
-		nfds = 0;
-
-		pfd[nfds].fd = midi_request_pipe[0];
-		pfd[nfds].events = POLLIN|POLLHUP|POLLERR;
-		nfds++;
-
-		if (Config->get_mmc_control() && _mmc_port && _mmc_port->selectable() >= 0) {
-			pfd[nfds].fd = _mmc_port->selectable();
-			pfd[nfds].events = POLLIN|POLLHUP|POLLERR;
-			ports[nfds] = _mmc_port;
-			DEBUG_TRACE (DEBUG::MidiIO, string_compose ("set up port #%1 for mmc @ %2\n", nfds, _mmc_port));
-			nfds++;
-		}
-
-		/* if MTC is being handled on a different port from MMC
-		   or we are not handling MMC at all, poll
-		   the relevant port.
-		*/
-
-		if (_mtc_port && (_mtc_port != _mmc_port || !Config->get_mmc_control()) && _mtc_port->selectable() >= 0) {
-			pfd[nfds].fd = _mtc_port->selectable();
-			pfd[nfds].events = POLLIN|POLLHUP|POLLERR;
-			ports[nfds] = _mtc_port;
-			DEBUG_TRACE (DEBUG::MidiIO, string_compose ("set up port #%1 for mtc @ %2\n", nfds, _mtc_port));
-			nfds++;
-		}
-
-		if (_midi_clock_port && (_midi_clock_port != _mmc_port || !Config->get_mmc_control()) && _midi_clock_port->selectable() >= 0) {
-			pfd[nfds].fd = _midi_clock_port->selectable();
-			pfd[nfds].events = POLLIN|POLLHUP|POLLERR;
-			ports[nfds] = _midi_clock_port;
-			DEBUG_TRACE (DEBUG::MidiIO, string_compose ("set up port #%1 for midi clock @ %2\n", nfds, _midi_clock_port));
-			nfds++;
-		}
-
-		/* if we are using MMC control, we obviously have to listen
-		   the relevant port.
-		*/
-
-		if (_midi_port && (_midi_port != _mmc_port || !Config->get_mmc_control()) && (_midi_port != _mtc_port) && _midi_port->selectable() >= 0) {
-			pfd[nfds].fd = _midi_port->selectable();
-			pfd[nfds].events = POLLIN|POLLHUP|POLLERR;
-			ports[nfds] = _midi_port;
-			DEBUG_TRACE (DEBUG::MidiIO, string_compose ("set up port #%1 for midi @ %2\n", nfds, _midi_port));
-			nfds++;
-		}
-
-		if (!midi_timeouts.empty()) {
-			timeout = 100; /* 10msecs */
-		} else {
-			timeout = -1; /* if there is no data, we don't care */
-		}
-
-	  again:
-		DEBUG_TRACE (DEBUG::MidiIO, string_compose ("MIDI poll on %1 fds for %2\n", nfds, timeout));
-		if (poll (pfd, nfds, timeout) < 0) {
-			if (errno == EINTR) {
-				/* gdb at work, perhaps */
-				goto again;
-			}
-
-			error << string_compose(_("MIDI thread poll failed (%1)"), strerror (errno)) << endmsg;
-
-			break;
-		}
-
-		nframes64_t now = engine().frame_time();
-
-		DEBUG_TRACE (DEBUG::MidiIO, "MIDI thread awake\n");
 
-		fds_ready = 0;
-
-		/* check the transport request pipe */
-
-		if (pfd[0].revents & ~POLLIN) {
-			error << _("Error on transport thread request pipe") << endmsg;
-			break;
-		}
-
-		if (pfd[0].revents & POLLIN) {
-
-			char foo[16];
-			
-			DEBUG_TRACE (DEBUG::MidiIO, "MIDI request FIFO ready\n");
-			fds_ready++;
-
-			/* empty the pipe of all current requests */
-
-			while (1) {
-				size_t nread = read (midi_request_pipe[0], &foo, sizeof (foo));
-
-				if (nread > 0) {
-					if ((size_t) nread < sizeof (foo)) {
-						break;
-					} else {
-						continue;
-					}
-				} else if (nread == 0) {
-					break;
-				} else if (errno == EAGAIN) {
-					break;
-				} else {
-					fatal << _("Error reading from transport request pipe") << endmsg;
-					/*NOTREACHED*/
-				}
-			}
-
-			while (midi_requests.read (&request, 1) == 1) {
-
-				switch (request->type) {
-				case MIDIRequest::PortChange:
-					/* restart poll with new ports */
-					DEBUG_TRACE (DEBUG::MidiIO, "rebind\n");
-					restart = true;
-					break;
-
-				case MIDIRequest::Quit:
-					delete request;
-					DEBUG_TRACE (DEBUG::MidiIO, "thread quit\n");
-					pthread_exit_pbd (0);
-					/*NOTREACHED*/
-					break;
-
-				default:
-					break;
-				}
-
-
-				delete request;
-			}
-
-		}
-
-		if (restart) {
-			DEBUG_TRACE (DEBUG::MidiIO, "ports changed, restart poll\n");
-			restart = false;
-			continue;
-		}
-
-		/* now read the rest of the ports */
-
-		for (int p = 1; p < nfds; ++p) {
-
-#ifndef NDEBUG
-			DEBUG_STR_SET(foo, "port #%1 revents = ");
-			DEBUG_STR(foo) << hex << pfd[p].revents << dec << endl;
-			DEBUG_TRACE (DEBUG::MidiIO, string_compose (DEBUG_STR(foo).str(), p));
-#endif
-
-			if ((pfd[p].revents & ~POLLIN)) {
-				// error << string_compose(_("Transport: error polling MIDI port %1 (revents =%2%3%4"), p, &hex, pfd[p].revents, &dec) << endmsg;
-				break;
-			}
-
-			if (pfd[p].revents & POLLIN) {
-				DEBUG_TRACE (DEBUG::MidiIO, string_compose ("MIDI fd # %1 has data ready @ %2\n", p, now));
-				fds_ready++;
-				ports[p]->parse (now);
-			}
-		}
-
-		/* timeout driven */
-
-		if (fds_ready < 2 && timeout != -1) {
-
-			DEBUG_TRACE (DEBUG::MidiIO, "Check timeouts\n");
-			for (MidiTimeoutList::iterator i = midi_timeouts.begin(); i != midi_timeouts.end(); ) {
-
-				MidiTimeoutList::iterator tmp;
-				tmp = i;
-				++tmp;
-
-				if (!(*i)()) {
-					midi_timeouts.erase (i);
-				}
-
-				i = tmp;
-			}
-		}
-	}
-}
 
diff --git a/libs/ardour/session_process.cc b/libs/ardour/session_process.cc
index 078ef260c6..882694cccf 100644
--- a/libs/ardour/session_process.cc
+++ b/libs/ardour/session_process.cc
@@ -51,10 +51,6 @@ using namespace std;
 void
 Session::process (nframes_t nframes)
 {
-	// This is no more the appropriate place to call cycle
-	// start. cycle_start needs to be called at the Route::roll()
-	// where the signals which we want to mixdown have been calculated.
-	//
 	MIDI::Manager::instance()->cycle_start(nframes);
 
 	_silent = false;
diff --git a/libs/ardour/session_state.cc b/libs/ardour/session_state.cc
index 3aaa3dbf22..f1bfa5ea92 100644
--- a/libs/ardour/session_state.cc
+++ b/libs/ardour/session_state.cc
@@ -219,7 +219,7 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	first_file_data_format_reset = true;
 	first_file_header_format_reset = true;
 	post_export_sync = false;
-	//midi_thread = (pthread_t) 0;
+	midi_control_ui = 0;
 
 	AudioDiskstream::allocate_working_buffers();
 
diff --git a/libs/ardour/source_factory.cc b/libs/ardour/source_factory.cc
index 7c8943a4f1..a44a372726 100644
--- a/libs/ardour/source_factory.cc
+++ b/libs/ardour/source_factory.cc
@@ -58,7 +58,6 @@ std::list<boost::weak_ptr<AudioSource> > SourceFactory::files_with_peaks;
 static void
 peak_thread_work ()
 {
-	PBD::notify_gui_about_thread_creation (pthread_self(), string ("peakbuilder-") + to_string (pthread_self(), std::dec));
 	SessionEvent::create_per_thread_pool (X_("PeakFile Builder "), 64);
 
 	while (true) {
diff --git a/libs/ardour/wscript b/libs/ardour/wscript
index b01260a30b..3e5f763461 100644
--- a/libs/ardour/wscript
+++ b/libs/ardour/wscript
@@ -124,6 +124,7 @@ libardour_sources = [
 	'midi_state_tracker.cc',
 	'midi_stretch.cc',
 	'midi_track.cc',
+	'midi_ui.cc',
 	'mix.cc',
 	'mtc_slave.cc',
 	'mtdm.cc',