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/*
* ALSA sequencer System services Client
* Copyright (c) 1998 by Frank van de Pol <F.K.W.van.de.Pol@inter.nl.net>
*
*
* 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 "driver.h"
#include "seq_system.h"
#include "seq_timer.h"
#include "seq_queue.h"
/* internal client that provide system services, access to timer etc. */
/*
* Port "Timer"
* - send tempo /start/stop etc. events to this port to manipulate the
* queue's timer. The queue address is specified in the destination
* part of the address
* - this port supports subscription. The received timer events are
* broadcasted to all subscribed clients.
*
* Port "Announce"
* - does not receive message
* - supports supscription. For each client or port attaching to or
* detaching from the system an announcement is send to the subscribed
* clients.
*
* Idea: the subscription mechanism might also work handy for distributing
* synchronisation and timing information. In this case we would ideally have
* a list of subscribers for each type of sync (time, tick), for each timing
* queue.
*
*/
/* client id of our system client */
static int sysclient;
static int timer_port;
static int announce_port;
/* call-back handler for timer events */
static int event_input_timer(snd_seq_event_t * ev, void *private_data)
{
/* handle Timer events */
switch (ev->type) {
/* timer stuff */
case SND_SEQ_EVENT_START:
//snd_printk("start playing!\n");
snd_seq_queue_timer_start(ev->dest.queue, ev->source.client);
break;
case SND_SEQ_EVENT_CONTINUE:
//snd_printk("continue playing!\n");
snd_seq_queue_timer_continue(ev->dest.queue, ev->source.client);
break;
case SND_SEQ_EVENT_STOP:
//snd_printk("stop playing!\n");
snd_seq_queue_timer_stop(ev->dest.queue, ev->source.client);
break;
case SND_SEQ_EVENT_TEMPO:
//snd_printk("tempo change!\n");
snd_seq_queue_timer_set_tempo(ev->dest.queue, ev->source.client, ev->data.control.value);
break;
}
return 1; /* success */
}
/* call-back function for event input */
static int event_input(snd_seq_event_t * ev, void *private_data)
{
if (ev) {
if (ev->dest.port == timer_port) {
/* handle Timer events */
event_input_timer(ev, private_data);
}
}
return 1; /* success */
}
/* register our internal client */
void snd_seq_system_client_init(void)
{
snd_seq_client_callback_t callbacks;
snd_seq_client_info_t inf;
snd_seq_port_info_t port;
/* register client */
callbacks.input = event_input;
sysclient = snd_seq_register_kernel_client(&callbacks, NULL);
/* set our name */
strcpy(inf.name, "System");
snd_seq_kernel_client_ctl(sysclient, SND_SEQ_IOCTL_SET_CLIENT_INFO, &inf);
/* register timer */
strcpy(port.name, "Timer");
port.capability = SND_SEQ_PORT_CAP_SUBSCRIPTION;
port.port_type = 0;
snd_seq_kernel_client_ctl(sysclient, SND_SEQ_IOCTL_CREATE_PORT, &port);
timer_port = port.port;
//snd_printk("Registered %s as port %d\n", port.name, timer_port);
/* register announcement port */
strcpy(port.name, "Announce");
port.capability = SND_SEQ_PORT_CAP_SUBSCRIPTION;
port.port_type = 0;
snd_seq_kernel_client_ctl(sysclient, SND_SEQ_IOCTL_CREATE_PORT, &port);
announce_port = port.port;
//snd_printk("Registered %s as port %d\n", port.name, timer_port);
}
/* unregister our internal client */
void snd_seq_system_client_done(void)
{
snd_seq_unregister_kernel_client(sysclient);
}
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