timer.cc

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/*
    Copyright (C) 2014 Tim Mayberry

    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 "pbd/timer.h"

namespace PBD {

Timer::Timer (unsigned int interval,
              const Glib::RefPtr<Glib::MainContext>& main_context)
        : m_timeout_source(NULL)
        , m_timeout_interval(interval)
        , m_main_context(main_context)
{

}

gboolean
Timer::_timeout_handler (void *data)
{
        Timer *const timer = static_cast<Timer*>(data);
        return timer->timeout_handler();
}

unsigned int
Timer::get_interval () const
{
        return m_timeout_interval;
}

void
Timer::set_interval (unsigned int new_interval)
{
        if (new_interval == m_timeout_interval) return;

        stop ();
        m_timeout_interval = new_interval;
        start ();
}

void
Timer::start()
{
        if (m_timeout_source) return;

        m_timeout_source = g_timeout_source_new (m_timeout_interval);

#if 0 // support priorites?
        if(priority != G_PRIORITY_DEFAULT)
                g_source_set_priority(source, priority);
#endif

        g_source_set_callback (m_timeout_source, &Timer::_timeout_handler, this, NULL);

        g_source_attach (m_timeout_source, m_main_context->gobj());
        // GMainContext also holds a reference
}

void
Timer::stop()
{
        if (m_timeout_source) {
                g_source_destroy (m_timeout_source);
                g_source_unref (m_timeout_source);
                m_timeout_source = NULL;
        }
}

bool
Timer::timeout_handler()
{
        return on_elapsed();
}

StandardTimer::StandardTimer(unsigned int interval,
                const Glib::RefPtr<Glib::MainContext>& main_context)
        : Timer(interval, main_context)
{ }

sigc::connection
StandardTimer::connect(const sigc::slot<void>& slot)
{
        if(m_signal.size() == 0) { start(); }

        return m_signal.connect(slot);
}

bool
StandardTimer::on_elapsed()
{
        if(m_signal.size() == 0)
        {
                stop();
                return false;
        }

        m_signal();
        return true;
}

BlinkTimer::BlinkTimer(unsigned int interval,
                const Glib::RefPtr<Glib::MainContext>& main_context)
        : Timer(interval, main_context)
{ }

sigc::connection
BlinkTimer::connect(const sigc::slot<void, bool>& slot)
{
        if(m_blink_signal.size() == 0) { start(); }

        return m_blink_signal.connect(slot);
}

bool
BlinkTimer::on_elapsed()
{
        static bool blink_on = false;

        if(m_blink_signal.size() == 0)
        {
                stop();
                return false;
        }

        m_blink_signal(blink_on = !blink_on);
        return true;
}

} // namespace PBD