add new control protocol related files

git-svn-id: svn://localhost/trunk/ardour2@443 d708f5d6-7413-0410-9779-e7cbd77b26cf

libs/ardour/control_protocol.cc

@@ -0,0 +1,242 @@
+/*
+    Copyright (C) 2006 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.
+
+    $Id$
+*/
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <poll.h>
+
+#include <pbd/pthread_utils.h>
+#include <pbd/error.h>
+#include <ardour/control_protocol.h>
+#include <ardour/configuration.h>
+#include <ardour/session.h>
+
+using namespace ARDOUR;
+using namespace std;
+
+#include "i18n.h"
+
+ControlProtocol::ControlProtocol (Session& s, string str)
+	: session (s), 
+	  _name (str)
+{
+	active_thread = 1;
+}
+
+ControlProtocol::~ControlProtocol ()
+{
+}
+
+void
+ControlProtocol::set_send (SendWhat sw)
+{
+	_send = sw;
+}
+
+int
+ControlProtocol::init_thread ()
+{
+	if (pipe (thread_request_pipe) != 0) {
+		error << string_compose (_("%1: cannot create thread request pipe (%1)"), _name, strerror (errno))
+		      << endmsg;
+		return -1;
+	}
+
+	if (fcntl (thread_request_pipe[0], F_SETFL, O_NONBLOCK)) {
+		error << string_compose(_("%1: cannot set O_NONBLOCK on read pipe (%2)"), _name, strerror (errno)) << endmsg;
+		return -1;
+	}
+
+	if (fcntl (thread_request_pipe[1], F_SETFL, O_NONBLOCK)) {
+		error << string_compose(_("%1: cannot set O_NONBLOCK on signal write pipe (%2)"), _name, strerror (errno)) << endmsg;
+		return -1;
+	}
+
+	if (pthread_create_and_store ("tranzport delivery", &_thread, 0, _thread_work, this)) {
+		error << string_compose (_("%1: could not create thread"), _name) << endmsg;
+		return -1;
+	}
+
+	return 0;
+}	
+
+int
+ControlProtocol::poke_thread (ThreadRequest::Type why)
+{
+	char c = (char) why;
+	return !(write (thread_request_pipe[1], &c, 1) == 1);
+}
+
+int
+ControlProtocol::start_thread ()
+{
+	return poke_thread (ThreadRequest::Start);
+}
+
+int
+ControlProtocol::stop_thread ()
+{
+	return poke_thread (ThreadRequest::Stop);
+}
+
+void
+ControlProtocol::set_active (bool yn)
+{
+	if (yn != active_thread) {
+
+		if (yn) {
+			/* make sure the feedback thread is alive */
+			start_thread ();
+		} else {
+			/* maybe put the feedback thread to sleep */
+			stop_thread ();
+		}
+		
+		ActiveChanged ();
+	}
+}
+
+void
+ControlProtocol::terminate_thread ()
+{
+	void* status;
+	poke_thread (ThreadRequest::Quit);
+	pthread_join (_thread, &status);
+}
+
+void*
+ControlProtocol::_thread_work (void* arg)
+{
+	return static_cast<ControlProtocol*> (arg)->thread_work ();
+}
+
+void*
+ControlProtocol::thread_work ()
+{
+	PBD::ThreadCreated (pthread_self(), _name);
+
+	struct pollfd pfd[1];
+	int timeout;
+
+	struct sched_param rtparam;
+	int err;
+
+	memset (&rtparam, 0, sizeof (rtparam));
+	rtparam.sched_priority = 3; /* XXX should be relative to audio (JACK) thread */
+	
+	if ((err = pthread_setschedparam (pthread_self(), SCHED_FIFO, &rtparam)) != 0) {
+		// do we care? not particularly.
+		info << string_compose (_("%1: delivery thread not running with realtime scheduling (%2)"), _name, strerror (errno)) << endmsg;
+	} 
+
+	pthread_setcancelstate (PTHREAD_CANCEL_ENABLE, 0);
+	pthread_setcanceltype (PTHREAD_CANCEL_ASYNCHRONOUS, 0);
+
+
+	if (active_thread) {
+		timeout = max (5, (int) Config->get_feedback_interval_ms());
+	} else {
+		timeout = -1;
+	}
+
+	while (1) {
+
+		pfd[0].fd = thread_request_pipe[0];
+		pfd[0].events = POLLIN|POLLHUP|POLLERR;
+
+		if (poll (pfd, 1, timeout) < 0) {
+			if (errno == EINTR) {
+				continue;
+			}
+			error << string_compose (_("Protocol \"%1\" thread: poll failed (%2)"), _name, strerror (errno))
+			      << endmsg;
+			break;
+		}
+
+		if (pfd[0].revents & ~POLLIN) {
+			error << string_compose (_("Error thread request pipe for protocol \"%1\""), _name) << endmsg;
+			break;
+		}
+
+		if (pfd[0].revents & POLLIN) {
+
+			char req;
+			
+			/* empty the pipe of all current requests */
+
+			while (1) {
+				size_t nread = read (thread_request_pipe[0], &req, sizeof (req));
+
+				if (nread == 1) {
+					switch ((ThreadRequest::Type) req) {
+					
+					case ThreadRequest::Start:
+						timeout = max (5, (int) Config->get_feedback_interval_ms());
+						active_thread++;
+						break;
+						
+					case ThreadRequest::Stop:
+						timeout = -1;
+						if (active_thread) {
+							active_thread--;
+						} 
+						break;
+						
+					case ThreadRequest::Quit:
+						pthread_exit_pbd (0);
+						/*NOTREACHED*/
+						break;
+						
+					default:
+						break;
+					}
+
+				} else if (nread == 0) {
+					break;
+				} else if (errno == EAGAIN) {
+					break;
+				} else {
+					fatal << string_compose (_("Error reading from thread request pipe for protocol \"%1\""), _name) << endmsg;
+					/*NOTREACHED*/
+				}
+			}
+		}
+		
+		if (!active_thread) {
+			continue;
+		}
+
+		cerr << ".\n";
+
+		if (send()) {
+			
+			list<Route*> routes = session.get_routes(); /* copies the routes */
+			
+			if (send_route_feedback ()) {
+				send_route_feedback (routes);
+			}
+
+			send_global_feedback ();
+		}
+	}
+
+	return 0;
+}