audioengine branch can now load and run at least one test session.

currently hard-coded to deal only with the situation where JACK is already running

gtk2_ardour/ardour_ui.cc

@@ -61,6 +61,7 @@
 #include "midi++/manager.h"
 
 #include "ardour/ardour.h"
+#include "ardour/audio_backend.h"
 #include "ardour/audioengine.h"
 #include "ardour/audiofilesource.h"
 #include "ardour/automation_watch.h"
@@ -373,6 +374,8 @@ ARDOUR_UI::ARDOUR_UI (int *argcp, char **argvp[], const char* localedir)
 	_process_thread->init ();
 
 	DPIReset.connect (sigc::mem_fun (*this, &ARDOUR_UI::resize_text_widgets));
+
+	attach_to_engine ();
 }
 
 GlobalPortMatrixWindow*
@@ -384,18 +387,10 @@ ARDOUR_UI::create_global_port_matrix (ARDOUR::DataType type)
 	return new GlobalPortMatrixWindow (_session, type);
 }
 
-int
+void
-ARDOUR_UI::create_engine ()
+ARDOUR_UI::attach_to_engine ()
 {
-	// this gets called every time by new_session()
+	engine = AudioEngine::instance();
-
-	if (engine) {
-		return 0;
-	}
-
-	loading_message (_("Starting audio engine"));
-
-	AudioEngine* engine = AudioEngine::instance();
 
 	engine->Stopped.connect (forever_connections, MISSING_INVALIDATOR, boost::bind (&ARDOUR_UI::engine_stopped, this), gui_context());
 	engine->Running.connect (forever_connections, MISSING_INVALIDATOR, boost::bind (&ARDOUR_UI::engine_running, this), gui_context());
@@ -405,8 +400,6 @@ ARDOUR_UI::create_engine ()
 	engine->BackendAvailable.connect_same_thread (forever_connections, boost::bind (&ARDOUR_UI::post_engine, this));
 
 	ARDOUR::Port::set_connecting_blocked (ARDOUR_COMMAND_LINE::no_connect_ports);
-
-	return 0;
 }
 
 void
@@ -414,7 +407,7 @@ ARDOUR_UI::post_engine ()
 {
 	cerr << "Backend available!\n";
 
-	/* Things to be done once we create the AudioEngine
+	/* Things to be done once we have a backend running in the AudioEngine
 	 */
 
 	ARDOUR::init_post_engine ();
@@ -2572,6 +2565,17 @@ ARDOUR_UI::get_session_parameters (bool quit_on_cancel, bool should_be_new, stri
 	int ret = -1;
 	bool likely_new = false;
 
+	/* if the audio/midi backend does not require setup, get our use of it underway
+	 * right here
+	 */
+
+	if (!EngineControl::need_setup()) {
+		vector<const AudioBackendInfo*> backends = AudioEngine::instance()->available_backends();
+		cerr << "Setting up backend " << backends.front()->name;
+		AudioEngine::instance()->set_backend (backends.front()->name, ARDOUR_COMMAND_LINE::backend_client_name, ARDOUR_COMMAND_LINE::backend_session_uuid);
+		AudioEngine::instance()->start ();
+	}
+
 	/* deal with any existing DIRTY session now, rather than later. don't
 	 * treat a non-dirty session this way, so that it stays visible 
 	 * as we bring up the new session dialog.
@@ -2693,10 +2697,6 @@ ARDOUR_UI::get_session_parameters (bool quit_on_cancel, bool should_be_new, stri
 			}
 		}
 	
-		if (create_engine ()) {
-			break;
-		}
-
 		if (Glib::file_test (session_path, Glib::FileTest (G_FILE_TEST_EXISTS | G_FILE_TEST_IS_DIR))) {
 
 			if (likely_new && !nsm) {

gtk2_ardour/ardour_ui.h

@@ -263,7 +263,7 @@ class ARDOUR_UI : public Gtkmm2ext::UI, public ARDOUR::SessionHandlePtr
 		session_add_midi_route (false);
 	}*/
 
-	int  create_engine ();
+        void attach_to_engine ();
 	void post_engine ();
 
 	gint exit_on_main_window_close (GdkEventAny *);

gtk2_ardour/engine_dialog.cc

@@ -44,6 +44,8 @@
 #include <gtkmm/stock.h>
 #include <gtkmm2ext/utils.h>
 
+#include "ardour/audio_backend.h"
+#include "ardour/audioengine.h"
 #include "ardour/rc_configuration.h"
 
 #include "pbd/convert.h"
@@ -594,33 +596,13 @@ EngineControl::build_command_line (vector<string>& cmd)
 bool
 EngineControl::need_setup ()
 {
-	return !engine_running();
+	vector<const ARDOUR::AudioBackendInfo*> backends = ARDOUR::AudioEngine::instance()->available_backends();
-}
 
-bool
+	if (backends.size() == 1 && backends.front()->already_configured()) {
-EngineControl::engine_running ()
-{
-        EnvironmentalProtectionAgency* global_epa = EnvironmentalProtectionAgency::get_global_epa ();
-        boost::scoped_ptr<EnvironmentalProtectionAgency> current_epa;
-
-        /* revert all environment settings back to whatever they were when
-	 * ardour started, because ardour's startup script may have reset
-	 * something in ways that interfere with finding/starting JACK.
-         */
-
-        if (global_epa) {
-                current_epa.reset (new EnvironmentalProtectionAgency(true)); /* will restore settings when we leave scope */
-                global_epa->restore ();
-        }
-
-	jack_status_t status;
-	jack_client_t* c = jack_client_open ("ardourprobe", JackNoStartServer, &status);
-
-	if (status == 0) {
-		jack_client_close (c);
-		return true;
-	}
 		return false;
+	}
+
+	return true;
 }
 
 int

libs/ardour/ardour/audio_backend.h

@@ -353,6 +353,15 @@ struct AudioBackendInfo {
 
     boost::shared_ptr<AudioBackend> (*backend_factory) (AudioEngine&);
     boost::shared_ptr<PortEngine> (*portengine_factory) (PortManager&);
+
+    /** Return true if the underlying mechanism/API has been
+     * configured and does not need (re)configuration in order
+     * to be usable. Return false otherwise.
+     *
+     * Note that this may return true if (re)configuration is possible,
+     * but not required. 
+     */
+    bool (*already_configured)();
 };
 
 } // namespace

libs/ardour/ardour/audioengine.h

@@ -72,7 +72,7 @@ public:
     virtual ~AudioEngine ();
     
     int discover_backends();
-    std::vector<std::string> available_backends() const;
+    std::vector<const AudioBackendInfo*> available_backends() const;
     std::string current_backend_name () const;
     int set_backend (const std::string&, const std::string& arg1, const std::string& arg2);
 

libs/ardour/ardour/jack_audiobackend.h

@@ -101,6 +101,8 @@ class JACKAudioBackend : public AudioBackend {
 
     void update_latencies ();
 
+    static bool already_configured();
+
   private:
     boost::shared_ptr<JackConnection>  _jack_connection; //< shared with JACKPortEngine
     bool            _running;
@@ -145,6 +147,8 @@ class JACKAudioBackend : public AudioBackend {
 
     ChanCount n_physical (unsigned long) const;
     
+    void preset_jack_startup_command ();
+
     /* pffooo */
 
     std::string  _target_device;

libs/ardour/ardour/jack_connection.h

@@ -21,11 +21,14 @@ class JackConnection {
 
     jack_client_t* jack() const { return _jack; }
 
+    PBD::Signal0<void> Connected;
     PBD::Signal1<void,const char*> Disconnected;
 
     void halted_callback ();
     void halted_info_callback (jack_status_t, const char*);
 
+    static bool server_running();
+
   private:
     jack_client_t* volatile _jack;
     std::string _client_name;

libs/ardour/ardour/jack_portengine.h

@@ -27,6 +27,8 @@
 
 #include <boost/shared_ptr.hpp>
 
+#include "pbd/signals.h"
+
 #include "ardour/port_engine.h"
 #include "ardour/types.h"
 
@@ -115,6 +117,9 @@ class JACKPortEngine : public PortEngine
     ChanCount n_physical (unsigned long flags) const;
     void get_physical (DataType type, unsigned long flags, std::vector<std::string>& phy) const;
 
+    PBD::ScopedConnection jack_connection_connection;
+    void connected_to_jack ();
+
 };
 
 } // namespace 

libs/ardour/audioengine.cc

@@ -537,13 +537,13 @@ AudioEngine::backend_discover (const string& path)
 	return info;
 }
 
-vector<string>
+vector<const AudioBackendInfo*>
 AudioEngine::available_backends() const
 {
-	vector<string> r;
+	vector<const AudioBackendInfo*> r;
 	
 	for (BackendMap::const_iterator i = _backends.begin(); i != _backends.end(); ++i) {
-		r.push_back (i->first);
+		r.push_back (i->second);
 	}
 
 	return r;
@@ -581,17 +581,21 @@ AudioEngine::set_backend (const std::string& name, const std::string& arg1, cons
 	drop_backend ();
 
 	try {
+		cerr << "Instantiate " << b->second->name << " with " << arg1 << " + " << arg2 << endl;
 
 		if (b->second->instantiate (arg1, arg2)) {
+			cerr << "i failed\n";
 			throw failed_constructor ();
 		}
 
+		cerr << "bf\n";
 		_backend = b->second->backend_factory (*this);
+		cerr << "pf\n";
 		_impl = b->second->portengine_factory (*this);
+		cerr << "done\n";
 
-
+	} catch (exception& e) {
-	} catch (...) {
+		error << string_compose (_("Could not create backend for %1: %2"), name, e.what()) << endmsg;
-		error << string_compose (_("Could not create backend for %1"), name) << endmsg;
 		return -1;
 	}
 

libs/ardour/globals.cc

@@ -72,6 +72,7 @@
 
 #include "ardour/analyser.h"
 #include "ardour/audio_library.h"
+#include "ardour/audio_backend.h"
 #include "ardour/audioengine.h"
 #include "ardour/audioplaylist.h"
 #include "ardour/audioregion.h"
@@ -333,15 +334,12 @@ ARDOUR::init (bool use_windows_vst, bool try_optimization, const char* localedir
 
 	ARDOUR::AudioEngine::create ();
 
-	uint32_t backend_cnt;
+	vector<const AudioBackendInfo*> backends = AudioEngine::instance()->available_backends();
 
-	if ((backend_cnt = AudioEngine::instance()->available_backends().size()) == 0) {
+	for (vector<const AudioBackendInfo*>::const_iterator i = backends.begin(); i != backends.end(); ++i) {
-		error << _("No audio/MIDI backends are available") << endmsg;
+		cerr << "BACKEND: [" << (*i)->name << "] already configured " << (*i)->already_configured() << endl;
-		return -1;
 	}
 
-	cerr << "We have " << backend_cnt << endl;
-
 	return 0;
 }
 

libs/ardour/jack_audiobackend.cc

@@ -354,12 +354,26 @@ JACKAudioBackend::raw_buffer_size(DataType t)
 	return (s != _raw_buffer_sizes.end()) ? s->second : 0;
 }
 
+void
+JACKAudioBackend::preset_jack_startup_command ()
+{
+	/* write parameter settings to ~/.jackdrc file so that next invocation
+	 * of JACK (presumably from a call to jack_client_open() from this
+	 * process) will do the right thing.
+	 */
+}
+
 /* ---- BASIC STATE CONTROL API: start/stop/pause/freewheel --- */
 
 int
 JACKAudioBackend::start ()
 {
 	if (!connected()) {
+
+		if (!_jack_connection->server_running()) {
+			preset_jack_startup_command ();
+		}
+		std::cerr << "Open JACK connection\n";
 		_jack_connection->open ();
 	}
 

libs/ardour/jack_connection.cc

@@ -55,6 +55,33 @@ JackConnection::~JackConnection ()
 	close ();
 }
 
+bool
+JackConnection::server_running ()
+{
+        EnvironmentalProtectionAgency* global_epa = EnvironmentalProtectionAgency::get_global_epa ();
+        boost::scoped_ptr<EnvironmentalProtectionAgency> current_epa;
+
+        /* revert all environment settings back to whatever they were when
+	 * ardour started, because ardour's startup script may have reset
+	 * something in ways that interfere with finding/starting JACK.
+         */
+
+        if (global_epa) {
+                current_epa.reset (new EnvironmentalProtectionAgency(true)); /* will restore settings when we leave scope */
+                global_epa->restore ();
+        }
+
+	jack_status_t status;
+	jack_client_t* c = jack_client_open ("ardourprobe", JackNoStartServer, &status);
+
+	if (status == 0) {
+		jack_client_close (c);
+		return true;
+	}
+
+	return false;
+}
+
 int
 JackConnection::open ()
 {

libs/ardour/jack_portengine.cc

@@ -20,13 +20,16 @@
 #include <string.h>
 #include <stdint.h>
 
-#include "pbd/failed_constructor.h"
+#include "pbd/error.h"
 
 #include "ardour/jack_portengine.h"
 #include "ardour/jack_connection.h"
 #include "ardour/port_manager.h"
 
+#include "i18n.h"
+
 using namespace ARDOUR;
+using namespace PBD;
 using std::string;
 using std::vector;
 
@@ -85,17 +88,7 @@ JACKPortEngine::JACKPortEngine (PortManager& pm, boost::shared_ptr<JackConnectio
 	: PortEngine (pm)
 	, _jack_connection (jc)
 {
-	jack_client_t* client = _jack_connection->jack();
+	_jack_connection->Connected.connect_same_thread (jack_connection_connection, boost::bind (&JACKPortEngine::connected_to_jack, this));
-
-	if (!client) {
-		throw failed_constructor ();
-	}
-
-	/* register callbacks for stuff that is our responsibility */
-
-        jack_set_port_registration_callback (client, _registration_callback, this);
-        jack_set_port_connect_callback (client, _connect_callback, this);
-        jack_set_graph_order_callback (client, _graph_order_callback, this);
 }
 
 JACKPortEngine::~JACKPortEngine ()
@@ -107,6 +100,24 @@ JACKPortEngine::~JACKPortEngine ()
 	_jack_connection.reset ();
 }
 
+void
+JACKPortEngine::connected_to_jack ()
+{
+	/* register callbacks for stuff that is our responsibility */
+
+	jack_client_t* client = _jack_connection->jack();
+
+	if (!client) {
+		/* how could this happen? it could ... */
+		error << _("Already disconnected from JACK before PortEngine could register callbacks") << endmsg;
+		return;
+	}
+
+        jack_set_port_registration_callback (client, _registration_callback, this);
+        jack_set_port_connect_callback (client, _connect_callback, this);
+        jack_set_graph_order_callback (client, _graph_order_callback, this);
+}
+
 void*
 JACKPortEngine::private_handle() const
 {
@@ -294,10 +305,12 @@ JACKPortEngine::n_physical (unsigned long flags) const
 	if (ports) {
 		for (uint32_t i = 0; ports[i]; ++i) {
 			if (!strstr (ports[i], "Midi-Through")) {
-				DataType t (jack_port_type (jack_port_by_name (_priv_jack, ports[i])));
+				DataType t = port_data_type (jack_port_by_name (_priv_jack, ports[i]));
+				if (t != DataType::NIL) {
 					c.set (t, c.get (t) + 1);
 				}
 			}
+		}
 		
 		jack_free (ports);
 	}