ref: 04ceeab0124ab3e08530e0ebbf93179c3ba7d31d
dir: /ext/midi/midi_alsa_seq.c/
/*
* Copyright 2004 Paul Brossier
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public License
* as published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
* 02111-1307, USA
*/
/* this file originally taken from Fluidsynth, Peter Hanappe and others. */
/** \file
* Midi driver for the Advanced Linux Sound Architecture (sequencer mode)
*/
#include "aubio_priv.h"
#include "midi.h"
#include "midi_event.h"
#include "midi_parser.h"
#include "midi_driver.h"
#include "config.h"
#if ALSA_SUPPORT
#define ALSA_PCM_NEW_HW_PARAMS_API
#include <alsa/asoundlib.h>
#include <pthread.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/poll.h>
/* #include <errno.h> //perror is in stdio.h */
#define AUBIO_ALSA_DEFAULT_SEQ_DEVICE "default"
#define AUBIO_ALSA_BUFFER_LENGTH 512
/* SCHED_FIFO priorities for ALSA threads (see pthread_attr_setschedparam) */
#define ALSA_RAWMIDI_SCHED_PRIORITY 90
#define ALSA_SEQ_SCHED_PRIORITY 90
/** aubio_alsa_seq_driver_t */
typedef struct {
aubio_midi_driver_t driver;
snd_seq_t *seq_handle;
int seq_port;
struct pollfd *pfd;
int npfd;
pthread_t thread;
int status;
} aubio_alsa_seq_driver_t;
aubio_midi_driver_t* new_aubio_alsa_seq_driver(//aubio_settings_t* settings,
handle_midi_event_func_t handler,
void* data);
int del_aubio_alsa_seq_driver(aubio_midi_driver_t* p);
static void* aubio_alsa_seq_run(void* d);
//void aubio_alsa_seq_driver_settings(aubio_settings_t* settings)
//{
// aubio_settings_register_str(settings, "midi.alsa_seq.device", "default", 0, NULL, NULL);
// aubio_settings_register_str(settings, "midi.alsa_seq.id", "pid", 0, NULL, NULL);
//}
/** new_aubio_alsa_seq_driver */
aubio_midi_driver_t* new_aubio_alsa_seq_driver(//aubio_settings_t* settings,
handle_midi_event_func_t handler, void* data)
{
int i, err;
aubio_alsa_seq_driver_t* dev; /**< object to return */
pthread_attr_t attr; /**< sequencer thread */
int sched = SCHED_FIFO; /**< default scheduling policy */
struct sched_param priority; /**< scheduling priority settings */
int count; /**< number of MIDI file descriptors */
struct pollfd *pfd = NULL; /**< poll file descriptor array (copied in dev->pfd) */
char* device = NULL; /**< the device name */
char* id = NULL;
char full_id[64];
char full_name[64];
/* not much use doing anything */
if (handler == NULL) {
AUBIO_ERR( "Invalid argument");
return NULL;
}
/* allocate the device */
dev = AUBIO_NEW(aubio_alsa_seq_driver_t);
if (dev == NULL) {
AUBIO_ERR( "Out of memory");
return NULL;
}
AUBIO_MEMSET(dev, 0, sizeof(aubio_alsa_seq_driver_t));
dev->seq_port = -1;
dev->driver.data = data;
dev->driver.handler = handler;
/* get the device name. if none is specified, use the default device. */
//aubio_settings_getstr(settings, "midi.alsa_seq.device", &device);
if (device == NULL) {
device = "default";
}
/* open the sequencer INPUT only, non-blocking */
//if ((err = snd_seq_open(&dev->seq_handle, device, SND_SEQ_OPEN_INPUT,
if ((err = snd_seq_open(&dev->seq_handle, device, SND_SEQ_OPEN_DUPLEX,
SND_SEQ_NONBLOCK)) < 0) {
AUBIO_ERR( "Error opening ALSA sequencer");
goto error_recovery;
}
/* get # of MIDI file descriptors */
count = snd_seq_poll_descriptors_count(dev->seq_handle, POLLIN);
if (count > 0) { /* make sure there are some */
pfd = AUBIO_MALLOC(sizeof (struct pollfd) * count);
dev->pfd = AUBIO_MALLOC(sizeof (struct pollfd) * count);
/* grab file descriptor POLL info structures */
count = snd_seq_poll_descriptors(dev->seq_handle, pfd, count, POLLIN);
}
for (i = 0; i < count; i++) { /* loop over file descriptors */
/* copy the input FDs */
if (pfd[i].events & POLLIN) { /* use only the input FDs */
dev->pfd[dev->npfd].fd = pfd[i].fd;
dev->pfd[dev->npfd].events = POLLIN;
dev->pfd[dev->npfd].revents = 0;
dev->npfd++;
}
}
AUBIO_FREE(pfd);
//aubio_settings_getstr(settings, "midi.alsa_seq.id", &id);
if (id != NULL) {
if (AUBIO_STRCMP(id, "pid") == 0) {
snprintf(full_id, 64, "aubio (%d)", getpid());
snprintf(full_name, 64, "aubio_port (%d)", getpid());
} else {
snprintf(full_id, 64, "aubio (%s)", id);
snprintf(full_name, 64, "aubio_port (%s)", id);
}
} else {
snprintf(full_id, 64, "aubio");
snprintf(full_name, 64, "aubio_port");
}
/* set the client name */
snd_seq_set_client_name (dev->seq_handle, full_id);
if ((dev->seq_port = snd_seq_create_simple_port (dev->seq_handle,
full_name,
SND_SEQ_PORT_CAP_WRITE | SND_SEQ_PORT_CAP_SUBS_WRITE |
SND_SEQ_PORT_CAP_READ | SND_SEQ_PORT_CAP_SUBS_READ |
SND_SEQ_PORT_CAP_DUPLEX,
SND_SEQ_PORT_TYPE_APPLICATION)) < 0)
{
AUBIO_ERR( "Error creating ALSA sequencer port");
goto error_recovery;
}
dev->status = AUBIO_MIDI_READY;
/* create the midi thread */
if (pthread_attr_init(&attr)) {
AUBIO_ERR( "Couldn't initialize midi thread attributes");
goto error_recovery;
}
/* use fifo scheduling. if it fails, use default scheduling. */
while (1) {
err = pthread_attr_setschedpolicy(&attr, sched);
if (err) {
AUBIO_MSG( "Couldn't set high priority scheduling for the MIDI input");
if (sched == SCHED_FIFO) {
sched = SCHED_OTHER;
continue;
} else {
AUBIO_ERR( "Couldn't set scheduling policy.");
goto error_recovery;
}
}
/* SCHED_FIFO will not be active without setting the priority */
priority.sched_priority = (sched == SCHED_FIFO) ? ALSA_SEQ_SCHED_PRIORITY : 0;
pthread_attr_setschedparam (&attr, &priority);
err = pthread_create(&dev->thread, &attr, aubio_alsa_seq_run, (void*) dev);
if (err) {
AUBIO_ERR( "Couldn't set high priority scheduling for the MIDI input");
if (sched == SCHED_FIFO) {
sched = SCHED_OTHER;
continue;
} else {
//AUBIO_LOG(AUBIO_PANIC, "Couldn't create the midi thread.");
AUBIO_ERR( "Couldn't create the midi thread.");
goto error_recovery;
}
}
break;
}
return (aubio_midi_driver_t*) dev;
error_recovery:
del_aubio_alsa_seq_driver((aubio_midi_driver_t*) dev);
return NULL;
}
/** del_aubio_alsa_seq_driver */
int del_aubio_alsa_seq_driver(aubio_midi_driver_t* p)
{
aubio_alsa_seq_driver_t* dev;
dev = (aubio_alsa_seq_driver_t*) p;
if (dev == NULL) {
return AUBIO_OK;
}
dev->status = AUBIO_MIDI_DONE;
/* cancel the thread and wait for it before cleaning up */
if (dev->thread) {
if (pthread_cancel(dev->thread)) {
AUBIO_ERR( "Failed to cancel the midi thread");
return AUBIO_FAIL;
}
if (pthread_join(dev->thread, NULL)) {
AUBIO_ERR( "Failed to join the midi thread");
return AUBIO_FAIL;
}
}
if (dev->seq_port >= 0) {
snd_seq_delete_simple_port (dev->seq_handle, dev->seq_port);
}
if (dev->seq_handle) {
snd_seq_drain_output(dev->seq_handle);
snd_seq_close(dev->seq_handle);
}
AUBIO_FREE(dev);
return AUBIO_OK;
}
/** aubio_alsa_seq_run */
void* aubio_alsa_seq_run(void* d)
{
int n;//, i;
snd_seq_event_t *seq_ev;
aubio_midi_event_t evt;
aubio_alsa_seq_driver_t* dev = (aubio_alsa_seq_driver_t*) d;
/* make sure the other threads can cancel this thread any time */
if (pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL)) {
AUBIO_ERR( "Failed to set the cancel state of the midi thread");
pthread_exit(NULL);
}
if (pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL)) {
AUBIO_ERR( "Failed to set the cancel state of the midi thread");
pthread_exit(NULL);
}
/* go into a loop until someone tells us to stop */
dev->status = AUBIO_MIDI_LISTENING;
while (dev->status == AUBIO_MIDI_LISTENING) {
/* is there something to read? */
n = poll(dev->pfd, dev->npfd, 1); /* use a 1 milliseconds timeout */
if (n < 0) {
perror("poll");
} else if (n > 0) {
/* read new events from the midi input port */
while ((n = snd_seq_event_input(dev->seq_handle, &seq_ev)) >= 0)
{
switch (seq_ev->type)
{
case SND_SEQ_EVENT_NOTEON:
evt.type = NOTE_ON;
evt.channel = seq_ev->data.note.channel;
evt.param1 = seq_ev->data.note.note;
evt.param2 = seq_ev->data.note.velocity;
break;
case SND_SEQ_EVENT_NOTEOFF:
evt.type = NOTE_OFF;
evt.channel = seq_ev->data.note.channel;
evt.param1 = seq_ev->data.note.note;
evt.param2 = seq_ev->data.note.velocity;
break;
case SND_SEQ_EVENT_KEYPRESS:
evt.type = KEY_PRESSURE;
evt.channel = seq_ev->data.note.channel;
evt.param1 = seq_ev->data.note.note;
evt.param2 = seq_ev->data.note.velocity;
break;
case SND_SEQ_EVENT_CONTROLLER:
evt.type = CONTROL_CHANGE;
evt.channel = seq_ev->data.control.channel;
evt.param1 = seq_ev->data.control.param;
evt.param2 = seq_ev->data.control.value;
break;
case SND_SEQ_EVENT_PITCHBEND:
evt.type = PITCH_BEND;
evt.channel = seq_ev->data.control.channel;
/* ALSA pitch bend is -8192 - 8191, we adjust it here */
evt.param1 = seq_ev->data.control.value + 8192;
break;
case SND_SEQ_EVENT_PGMCHANGE:
evt.type = PROGRAM_CHANGE;
evt.channel = seq_ev->data.control.channel;
evt.param1 = seq_ev->data.control.value;
break;
case SND_SEQ_EVENT_CHANPRESS:
evt.type = CHANNEL_PRESSURE;
evt.channel = seq_ev->data.control.channel;
evt.param1 = seq_ev->data.control.value;
break;
default:
continue; /* unhandled event, next loop iteration */
}
/* send the events to the next link in the chain */
(*dev->driver.handler)(dev->driver.data, &evt);
/* dump input on output */
//snd_seq_ev_set_source(new_ev, dev->seq_port);
//snd_seq_ev_set_dest(seq_ev,dev->seq_handle,dev->seq_client);
//snd_seq_ev_set_subs(new_ev);
//snd_seq_ev_set_direct(new_ev);
//snd_seq_event_output(dev->seq_handle, new_ev);
//snd_seq_drain_output(dev->seq_handle);
}
}
if ((n < 0) && (n != -EAGAIN)) {
AUBIO_ERR( "Error occured while reading ALSA sequencer events");
dev->status = AUBIO_MIDI_DONE;
}
// /* added by piem to handle new data to output */
// while (/* get new data, but from where ??? (n = snd_seq_event_output(dev->seq_handle, seq_ev)) >= 0*/ )
// {
// /* dump input on output */
// snd_seq_ev_set_source(new_ev, dev->seq_port);
// //snd_seq_ev_set_dest(seq_ev,dev->seq_handle,dev->seq_client);
// snd_seq_ev_set_subs(new_ev);
// snd_seq_ev_set_direct(new_ev);
// snd_seq_event_output(dev->seq_handle, new_ev);
// snd_seq_drain_output(dev->seq_handle);
// }
}
pthread_exit(NULL);
}
snd_seq_event_t ev;
void aubio_midi_direct_output(aubio_midi_driver_t * d, aubio_midi_event_t * event)
{
aubio_alsa_seq_driver_t* dev = (aubio_alsa_seq_driver_t*) d;
switch(event->type)
{
case NOTE_ON:
ev.type = SND_SEQ_EVENT_NOTEON;
ev.data.note.channel = event->channel;
ev.data.note.note = event->param1;
ev.data.note.velocity = event->param2;
//AUBIO_ERR( "NOTE_ON %d\n", event->param1);
break;
case NOTE_OFF:
ev.type = SND_SEQ_EVENT_NOTEOFF;
ev.data.note.channel = event->channel;
ev.data.note.note = event->param1;
ev.data.note.velocity = event->param2;
//AUBIO_ERR( "NOTE_OFF %d\n", event->param1);
break;
default:
break;
}
if (ev.type == SND_SEQ_EVENT_NOTEOFF || ev.type == SND_SEQ_EVENT_NOTEON ) {
snd_seq_ev_set_subs(&ev);
snd_seq_ev_set_direct(&ev);
snd_seq_ev_set_source(&ev, dev->seq_port);
snd_seq_event_output_direct(dev->seq_handle, &ev);
}
}
#endif /* #if ALSA_SUPPORT */