ref: 92c70f602c2fcbcffc26b52d2fe4b6bbb8a162e5
dir: /ext/midi/midi_alsa_raw.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 */ #include "aubio_priv.h" #include "midi.h" #include "midi_event.h" #include "midi_parser.h" #include "midi_driver.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 */ #include "config.h" #define AUBIO_ALSA_DEFAULT_MIDI_DEVICE "default" /** \bug double define? */ #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_midi_alsa_raw_driver_t */ typedef struct { aubio_midi_driver_t driver; snd_rawmidi_t *rawmidi_in; snd_rawmidi_t *rawmidi_out; struct pollfd *pfd; int npfd; pthread_t thread; int status; unsigned char buffer[AUBIO_ALSA_BUFFER_LENGTH]; aubio_midi_parser_t* parser; } aubio_midi_alsa_raw_driver_t; aubio_midi_driver_t* new_aubio_midi_alsa_raw_driver(//aubio_settings_t* settings, handle_midi_event_func_t handler, void* event_handler_data); int del_aubio_midi_alsa_raw_driver(aubio_midi_driver_t* p); static void* aubio_midi_alsa_raw_run(void* d); /************************************************************** * * Alsa MIDI driver * */ //void aubio_midi_alsa_raw_driver_settings(aubio_settings_t* settings) //{ // aubio_settings_register_str(settings, "midi.alsa.device", "default", 0, NULL, NULL); //} /** new_aubio_midi_alsa_raw_driver */ aubio_midi_driver_t* new_aubio_midi_alsa_raw_driver( //aubio_settings_t* settings, handle_midi_event_func_t handler, void* data) { int i, err; aubio_midi_alsa_raw_driver_t* dev; pthread_attr_t attr; int sched = SCHED_FIFO; struct sched_param priority; int count; struct pollfd *pfd = NULL; char* device = NULL; /* not much use doing anything */ if (handler == NULL) { AUBIO_ERR("Invalid argument"); return NULL; } /* allocate the device */ dev = AUBIO_NEW(aubio_midi_alsa_raw_driver_t); if (dev == NULL) { AUBIO_ERR( "Out of memory"); return NULL; } AUBIO_MEMSET(dev, 0, sizeof(aubio_midi_alsa_raw_driver_t)); dev->driver.handler = handler; dev->driver.data = data; /* allocate one event to store the input data */ dev->parser = new_aubio_midi_parser(); if (dev->parser == NULL) { AUBIO_ERR( "Out of memory"); goto error_recovery; } /* get the device name. if none is specified, use the default device. */ //aubio_settings_getstr(settings, "midi.alsa.device", &device); if (device == NULL) { device = "default"; } /* open the hardware device. only use midi in. */ if ((err = snd_rawmidi_open(&dev->rawmidi_in, NULL, device, SND_RAWMIDI_NONBLOCK)) < 0) { //if ((err = snd_rawmidi_open(&dev->rawmidi_in, &dev->rawmidi_out, device, SND_RAWMIDI_NONBLOCK)) < 0) { AUBIO_ERR( "Error opening ALSA raw MIDI IN port"); goto error_recovery; } /* get # of MIDI file descriptors */ count = snd_rawmidi_poll_descriptors_count(dev->rawmidi_in); 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_rawmidi_poll_descriptors(dev->rawmidi_in, pfd, count); } /* copy the input FDs */ for (i = 0; i < count; i++) { /* loop over file descriptors */ 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); 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; } /* Was: "use fifo scheduling. if it fails, use default scheduling." */ /* Now normal scheduling is used by default for the MIDI thread. The reason is, * that fluidsynth works better with low latencies under heavy load, if only the * audio thread is prioritized. * With MIDI at ordinary priority, that could result in individual notes being played * a bit late. On the other hand, if the audio thread is delayed, an audible dropout * is the result. * To reproduce this: Edirol UA-1 USB-MIDI interface, four buffers * with 45 samples each (roughly 4 ms latency), ravewave soundfont. -MN */ /* Not so sure anymore. We're losing MIDI data, if we can't keep up with * the speed it is generated. */ /* AUBIO_MSG("Note: High-priority scheduling for the MIDI thread was intentionally disabled."); sched=SCHED_OTHER;*/ while (1) { err = pthread_attr_setschedpolicy(&attr, sched); if (err) { //AUBIO_LOG(AUBIO_WARN, "Couldn't set high priority scheduling for the MIDI input"); 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_RAWMIDI_SCHED_PRIORITY : 0; pthread_attr_setschedparam (&attr, &priority); err = pthread_create(&dev->thread, &attr, aubio_midi_alsa_raw_run, (void*) dev); 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 create the midi thread."); goto error_recovery; } } break; } return (aubio_midi_driver_t*) dev; error_recovery: del_aubio_midi_alsa_raw_driver((aubio_midi_driver_t*) dev); return NULL; } /** del_aubio_midi_alsa_raw_driver */ int del_aubio_midi_alsa_raw_driver(aubio_midi_driver_t* p) { aubio_midi_alsa_raw_driver_t* dev; dev = (aubio_midi_alsa_raw_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->rawmidi_in) { snd_rawmidi_drain(dev->rawmidi_in); snd_rawmidi_close(dev->rawmidi_in); } if (dev->rawmidi_out) { snd_rawmidi_drain(dev->rawmidi_out); snd_rawmidi_close(dev->rawmidi_in); } if (dev->parser != NULL) { del_aubio_midi_parser(dev->parser); } AUBIO_FREE(dev); return AUBIO_OK; } /** aubio_midi_alsa_raw_run */ void * aubio_midi_alsa_raw_run(void* d) { int n, i; aubio_midi_event_t* evt; aubio_midi_alsa_raw_driver_t* dev = (aubio_midi_alsa_raw_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? */ /* use a 100 milliseconds timeout */ n = poll(dev->pfd, dev->npfd, 100); if (n < 0) { perror("poll"); } else if (n > 0) { /* read new data */ n = snd_rawmidi_read(dev->rawmidi_in, dev->buffer, AUBIO_ALSA_BUFFER_LENGTH); if ((n < 0) && (n != -EAGAIN)) { AUBIO_ERR( "Failed to read the midi input"); dev->status = AUBIO_MIDI_DONE; } /* let the parser convert the data into events */ for (i = 0; i < n; i++) { evt = aubio_midi_parser_parse(dev->parser, dev->buffer[i]); if (evt != NULL) { (*dev->driver.handler)(dev->driver.data, evt); } } }; } pthread_exit(NULL); } #endif /* #if ALSA_SUPPORT */