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Changes to allow external synchronisation + fix to get external midi working again.

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This commit is contained in:
Frank van de Pol 1999-08-08 17:41:09 +00:00
parent 4692649d56
commit b6b50c7aa4
1 changed files with 80 additions and 7 deletions
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87
test/playmidi1.c
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@ -73,7 +73,7 @@ static int source_channel = 0;
static int source_port = 0;
static int verbose = 0;
static int slave = 0;
static int slave = 0; /* allow external sync */
#define VERB_INFO 1
#define VERB_MUCH 2
@ -81,6 +81,7 @@ static int slave = 0;
static void alsa_start_timer(void);
static void alsa_stop_timer(void);
static void wait_start(void);
static inline double tick2time_dbl(int tick)
@ -197,7 +198,13 @@ static void do_header(int format, int ntracks, int division)
}
/* start playing... */
if (!slave)
if (slave) {
if (verbose >= VERB_INFO)
printf("Wait till timer starts...\n");
wait_start();
if (verbose >= VERB_INFO)
printf("Go!\n");
} else
alsa_start_timer();
}
@ -290,7 +297,8 @@ static void do_tempo(int us)
set_timer_event_header(&ev, SND_SEQ_EVENT_TEMPO);
ev.data.control.value = us;
write_ev(&ev);
if (!slave)
write_ev(&ev);
}
static void do_noteon(int chan, int pitch, int vol)
@ -436,7 +444,7 @@ static void alsa_sync(void)
/* dump buffer */
left = snd_seq_flush_output(seq_handle);
/* wait the echo event which I sent. */
/* wait for the timer start event */
#ifdef USE_BLOCKING_MODE
/* read event - blocked until any event is read */
left = snd_seq_event_input(seq_handle, &input_event);
@ -470,6 +478,49 @@ static void alsa_sync(void)
}
/* wait for start of the queue */
static void wait_start(void)
{
int left;
snd_seq_event_t* input_event;
/* wait the start event from the system timer */
do {
#ifdef USE_BLOCKING_MODE
/* read event - blocked until any event is read */
left = snd_seq_event_input(seq_handle, &input_event);
#else
/* read event - using select syscall */
while ((left = snd_seq_event_input(seq_handle, &input_event)) >= 0 &&
input_event == NULL) {
int seqfd;
fd_set fds;
seqfd = snd_seq_file_descriptor(seq_handle);
FD_ZERO(&fds);
FD_SET(seqfd, &fds);
if ((left = select(seqfd + 1, &fds, NULL, NULL, NULL)) < 0) {
printf("select error = %i (%s)\n", left, snd_strerror(left));
exit(1);
}
}
#endif
if (left < 0) {
printf("alsa_sync error!:%s\n", snd_strerror(left));
return;
}
if (verbose >= VERB_MUCH)
printf("wait_start got event. type=%d, flags=%d\n",
input_event->type, input_event->flags);
snd_seq_free_event(input_event);
} while (input_event->type != SND_SEQ_EVENT_START);
if (verbose >= VERB_MUCH)
printf("start received\n");
}
/* print usage */
static void usage(void)
{
@ -532,7 +583,7 @@ int main(int argc, char *argv[])
/* open sequencer device */
/* Here we open the device read/write mode. */
/* Becase we write SND_SEQ_EVENT_ECHO to myself to sync. */
/* Because we write SND_SEQ_EVENT_ECHO to myself to sync. */
tmp = snd_seq_open(&seq_handle, SND_SEQ_OPEN);
if (tmp < 0) {
perror("open /dev/snd/seq");
@ -548,14 +599,16 @@ int main(int argc, char *argv[])
perror("block_mode");
exit(1);
}
/* set name */
/* set event filter to recieve only echo event */
/* if running in slave mode also listen for START event */
memset(&inf, 0, sizeof(snd_seq_client_info_t));
inf.filter |= SND_SEQ_FILTER_USE_EVENT;
memset(&inf.event_filter, 0, sizeof(inf.event_filter));
snd_seq_set_bit(SND_SEQ_EVENT_ECHO, inf.event_filter);
if (slave)
snd_seq_set_bit(SND_SEQ_EVENT_START, inf.event_filter);
strcpy(inf.name, "MIDI file player");
if (snd_seq_set_client_info(seq_handle, &inf) < 0) {
perror("ioctl");
@ -577,6 +630,7 @@ int main(int argc, char *argv[])
source_port = src_port_info.port;
/* setup queue */
bzero(&queue_info,sizeof(queue_info));
queue_info.used = 1;
tmp = snd_seq_set_queue_client(seq_handle, dest_queue, &queue_info);
if (tmp < 0) {
@ -585,6 +639,7 @@ int main(int argc, char *argv[])
}
/* setup subscriber */
bzero(&subscribe,sizeof(subscribe));
if (verbose >= VERB_INFO)
printf("debug subscribe src_port_info.client=%d\n",
src_port_info.client);
@ -601,8 +656,26 @@ int main(int argc, char *argv[])
perror("subscribe");
exit(1);
}
/* subscribe for timer START event */
if (slave) {
subscribe.sender.client = SND_SEQ_CLIENT_SYSTEM;
subscribe.sender.queue = dest_queue;
subscribe.sender.port = SND_SEQ_PORT_SYSTEM_TIMER;
subscribe.dest.client = snd_seq_client_id(seq_handle);
subscribe.dest.port = src_port_info.port;
subscribe.dest.queue = dest_queue;
subscribe.realtime = 0;
subscribe.exclusive = 0;
tmp = snd_seq_subscribe_port(seq_handle, &subscribe);
if (tmp < 0) {
perror("subscribe");
exit(1);
}
}
/* change pool size */
bzero(&pool,sizeof(pool));
pool.output_pool = WRITE_POOL_SIZE;
pool.input_pool = READ_POOL_SIZE;
pool.output_room = WRITE_POOL_SPACE;