ardour/libs/surfaces/websockets/ardour_websockets.cc
Luciano Iam e3569b6469
WebSockets: notify server there are pending client updates
This is an update to the surface ArdourFeedback class that is needed to support
the new event loop integration method.

The various session event callbacks cannot be queued in the surface event loop
because that would create a delay between the time such events are fired and
the time for writing to clients arrive, due to lws_service() blocking while
it waits to read. To solve this issue a helper AbstractUI is created for
catching events as soon as possible and issuing a call to lws_cancel_service().

See WebsocketsServer::glib_idle_callback()
2021-06-13 22:00:29 +02:00

139 lines
3.6 KiB
C++

/*
* Copyright (C) 2009-2012 Carl Hetherington <carl@carlh.net>
* Copyright (C) 2009-2014 David Robillard <d@drobilla.net>
* Copyright (C) 2009-2017 Paul Davis <paul@linuxaudiosystems.com>
* Copyright (C) 2012-2016 Tim Mayberry <mojofunk@gmail.com>
* Copyright (C) 2013-2019 Robin Gareus <robin@gareus.org>
* Copyright (C) 2015-2016 Ben Loftis <ben@harrisonconsoles.com>
* Copyright (C) 2015-2018 John Emmas <john@creativepost.co.uk>
* Copyright (C) 2015 Johannes Mueller <github@johannes-mueller.org>
* Copyright (C) 2016-2018 Len Ovens <len@ovenwerks.net>
* Copyright (C) 2020 Luciano Iam <oss@lucianoiam.com>
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "ardour/session.h"
#include "ardour_websockets.h"
using namespace ARDOUR;
using namespace ArdourSurface;
#include "pbd/abstract_ui.cc" // instantiate template
ArdourWebsockets::ArdourWebsockets (Session& s)
: ControlProtocol (s, X_ (surface_name))
, AbstractUI<ArdourWebsocketsUIRequest> (name ())
, _mixer (*this)
, _transport (*this)
, _server (*this)
, _feedback (*this)
, _dispatcher (*this)
{
_components.push_back (&_mixer);
_components.push_back (&_transport);
_components.push_back (&_server);
_components.push_back (&_feedback);
_components.push_back (&_dispatcher);
}
ArdourWebsockets::~ArdourWebsockets ()
{
stop ();
}
void*
ArdourWebsockets::request_factory (uint32_t num_requests)
{
/* AbstractUI<T>::request_buffer_factory() is a template method only
instantiated in this source module. To provide something visible for
use in the interface/descriptor, we have this static method that is
template-free.
*/
return request_buffer_factory (num_requests);
}
int
ArdourWebsockets::set_active (bool yn)
{
if (yn != active ()) {
if (yn) {
if (start ()) {
return -1;
}
} else {
if (stop ()) {
return -1;
}
}
}
return ControlProtocol::set_active (yn);
}
void
ArdourWebsockets::thread_init ()
{
pthread_set_name (event_loop_name ().c_str ());
PBD::notify_event_loops_about_thread_creation (pthread_self (), event_loop_name (), 2048);
SessionEvent::create_per_thread_pool (event_loop_name (), 128);
}
void
ArdourWebsockets::do_request (ArdourWebsocketsUIRequest* req)
{
if (req->type == CallSlot) {
call_slot (MISSING_INVALIDATOR, req->the_slot);
} else if (req->type == Quit) {
stop ();
}
}
int
ArdourWebsockets::start ()
{
/* startup the event loop thread */
BaseUI::run ();
for (std::vector<SurfaceComponent*>::iterator it = _components.begin ();
it != _components.end (); ++it) {
int rc = (*it)->start ();
if (rc != 0) {
BaseUI::quit ();
return -1;
}
}
PBD::info << "ArdourWebsockets: started" << endmsg;
return 0;
}
int
ArdourWebsockets::stop ()
{
for (std::vector<SurfaceComponent*>::iterator it = _components.begin ();
it != _components.end (); ++it) {
(*it)->stop ();
}
BaseUI::quit ();
PBD::info << "ArdourWebsockets: stopped" << endmsg;
return 0;
}