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livetrax/libs/backends/alsa/alsa_rawmidi.cc

600 lines
15 KiB
C++

/*
* Copyright (C) 2014 Robin Gareus <robin@gareus.org>
* Copyright (C) 2010 Devin Anderson
*
* 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 <unistd.h>
#include <glibmm.h>
#include "alsa_rawmidi.h"
#include "rt_thread.h"
#include "pbd/error.h"
#include "i18n.h"
using namespace ARDOUR;
/* max bytes per individual midi-event
* events larger than this are ignored */
#define MaxAlsaRawEventSize (64)
#ifndef NDEBUG
#define _DEBUGPRINT(STR) fprintf(stderr, STR);
#else
#define _DEBUGPRINT(STR) ;
#endif
AlsaRawMidiIO::AlsaRawMidiIO (const char *device, const bool input)
: _state (-1)
, _running (false)
, _device (0)
, _pfds (0)
, _sample_length_us (1e6 / 48000.0)
, _period_length_us (1.024e6 / 48000.0)
, _samples_per_period (1024)
, _rb (0)
{
pthread_mutex_init (&_notify_mutex, 0);
pthread_cond_init (&_notify_ready, 0);
init (device, input);
}
AlsaRawMidiIO::~AlsaRawMidiIO ()
{
if (_device) {
snd_rawmidi_close (_device);
_device = 0;
}
delete _rb;
pthread_mutex_destroy (&_notify_mutex);
pthread_cond_destroy (&_notify_ready);
free (_pfds);
}
void
AlsaRawMidiIO::init (const char *device_name, const bool input)
{
if (snd_rawmidi_open (
input ? &_device : NULL,
input ? NULL : &_device,
device_name, SND_RAWMIDI_NONBLOCK) < 0) {
return;
}
_npfds = snd_rawmidi_poll_descriptors_count (_device);
if (_npfds < 1) {
_DEBUGPRINT("AlsaRawMidiIO: no poll descriptor(s).\n");
snd_rawmidi_close (_device);
_device = 0;
return;
}
_pfds = (struct pollfd*) malloc (_npfds * sizeof(struct pollfd));
snd_rawmidi_poll_descriptors (_device, _pfds, _npfds);
// MIDI (hw port) 31.25 kbaud
// worst case here is 8192 SPP and 8KSPS for which we'd need
// 4000 bytes sans MidiEventHeader.
// since we're not always in sync, let's use 4096.
_rb = new RingBuffer<uint8_t>(4096 + 4096 * sizeof(MidiEventHeader));
#if 0
_state = 0;
#else
snd_rawmidi_params_t *params;
if (snd_rawmidi_params_malloc (&params)) {
goto initerr;
}
if (snd_rawmidi_params_current (_device, params)) {
goto initerr;
}
if (snd_rawmidi_params_set_avail_min (_device, params, 1)) {
goto initerr;
}
if ( snd_rawmidi_params_set_buffer_size (_device, params, 64)) {
goto initerr;
}
if (snd_rawmidi_params_set_no_active_sensing (_device, params, 1)) {
goto initerr;
}
_state = 0;
return;
initerr:
_DEBUGPRINT("AlsaRawMidiIO: parameter setup error\n");
snd_rawmidi_close (_device);
_device = 0;
#endif
return;
}
static void * pthread_process (void *arg)
{
AlsaRawMidiIO *d = static_cast<AlsaRawMidiIO *>(arg);
d->main_process_thread ();
pthread_exit (0);
return 0;
}
int
AlsaRawMidiIO::start ()
{
if (_realtime_pthread_create (SCHED_FIFO, -19,
&_main_thread, pthread_process, this))
{
if (pthread_create (&_main_thread, NULL, pthread_process, this)) {
PBD::error << _("AlsaRawMidiIO: Failed to create process thread.") << endmsg;
return -1;
} else {
PBD::warning << _("AlsaRawMidiIO: Cannot acquire realtime permissions.") << endmsg;
}
}
int timeout = 5000;
while (!_running && --timeout > 0) { Glib::usleep (1000); }
if (timeout == 0 || !_running) {
return -1;
}
return 0;
}
int
AlsaRawMidiIO::stop ()
{
void *status;
if (!_running) {
return 0;
}
_running = false;
pthread_mutex_lock (&_notify_mutex);
pthread_cond_signal (&_notify_ready);
pthread_mutex_unlock (&_notify_mutex);
if (pthread_join (_main_thread, &status)) {
PBD::error << _("AlsaRawMidiIO: Failed to terminate.") << endmsg;
return -1;
}
return 0;
}
void
AlsaRawMidiIO::setup_timing (const size_t samples_per_period, const float samplerate)
{
_period_length_us = (double) samples_per_period * 1e6 / samplerate;
_sample_length_us = 1e6 / samplerate;
_samples_per_period = samples_per_period;
}
void
AlsaRawMidiIO::sync_time (const uint64_t tme)
{
// TODO consider a PLL, if this turns out to be the bottleneck for jitter
// also think about using
// snd_pcm_status_get_tstamp() and snd_rawmidi_status_get_tstamp()
// instead of monotonic clock.
#ifdef DEBUG_TIMING
double tdiff = (_clock_monotonic + _period_length_us - tme) / 1000.0;
if (abs(tdiff) >= .05) {
printf("AlsaRawMidiIO MJ: %.1f ms\n", tdiff);
}
#endif
_clock_monotonic = tme;
}
///////////////////////////////////////////////////////////////////////////////
// select sleeps _at most_ (compared to usleep() which sleeps at least)
static void select_sleep (uint32_t usec) {
if (usec <= 10) return;
fd_set fd;
int max_fd=0;
struct timeval tv;
tv.tv_sec = usec / 1000000;
tv.tv_usec = usec % 1000000;
FD_ZERO (&fd);
select (max_fd, &fd, NULL, NULL, &tv);
}
///////////////////////////////////////////////////////////////////////////////
AlsaRawMidiOut::AlsaRawMidiOut (const char *device)
: AlsaRawMidiIO (device, false)
{
}
int
AlsaRawMidiOut::send_event (const pframes_t time, const uint8_t *data, const size_t size)
{
const uint32_t buf_size = sizeof (MidiEventHeader) + size;
if (_rb->write_space() < buf_size) {
_DEBUGPRINT("AlsaRawMidiOut: ring buffer overflow\n");
return -1;
}
struct MidiEventHeader h (_clock_monotonic + time * _sample_length_us, size);
_rb->write ((uint8_t*) &h, sizeof(MidiEventHeader));
_rb->write (data, size);
if (pthread_mutex_trylock (&_notify_mutex) == 0) {
pthread_cond_signal (&_notify_ready);
pthread_mutex_unlock (&_notify_mutex);
}
return 0;
}
void *
AlsaRawMidiOut::main_process_thread ()
{
_running = true;
pthread_mutex_lock (&_notify_mutex);
while (_running) {
bool have_data = false;
struct MidiEventHeader h(0,0);
uint8_t data[MaxAlsaRawEventSize];
const uint32_t read_space = _rb->read_space();
if (read_space > sizeof(MidiEventHeader)) {
if (_rb->read ((uint8_t*)&h, sizeof(MidiEventHeader)) != sizeof(MidiEventHeader)) {
_DEBUGPRINT("AlsaRawMidiOut: Garbled MIDI EVENT HEADER!!\n");
break;
}
assert (read_space >= h.size);
if (h.size > MaxAlsaRawEventSize) {
_rb->increment_read_idx (h.size);
_DEBUGPRINT("AlsaRawMidiOut: MIDI event too large!\n");
continue;
}
if (_rb->read (&data[0], h.size) != h.size) {
_DEBUGPRINT("AlsaRawMidiOut: Garbled MIDI EVENT DATA!!\n");
break;
}
have_data = true;
}
if (!have_data) {
pthread_cond_wait (&_notify_ready, &_notify_mutex);
continue;
}
uint64_t now = g_get_monotonic_time();
while (h.time > now + 500) {
select_sleep(h.time - now);
now = g_get_monotonic_time();
}
retry:
int perr = poll (_pfds, _npfds, 10 /* ms */);
if (perr < 0) {
PBD::error << _("AlsaRawMidiOut: Error polling device. Terminating Midi Thread.") << endmsg;
break;
}
if (perr == 0) {
_DEBUGPRINT("AlsaRawMidiOut: poll() timed out.\n");
goto retry;
}
unsigned short revents = 0;
if (snd_rawmidi_poll_descriptors_revents (_device, _pfds, _npfds, &revents)) {
PBD::error << _("AlsaRawMidiOut: Failed to poll device. Terminating Midi Thread.") << endmsg;
break;
}
if (revents & (POLLERR | POLLHUP | POLLNVAL)) {
PBD::error << _("AlsaRawMidiOut: poll error. Terminating Midi Thread.") << endmsg;
break;
}
if (!(revents & POLLOUT)) {
_DEBUGPRINT("AlsaRawMidiOut: POLLOUT not ready.\n");
select_sleep (1000);
goto retry;
}
ssize_t err = snd_rawmidi_write (_device, data, h.size);
if ((err == -EAGAIN) || (err == -EWOULDBLOCK)) {
select_sleep (1000);
goto retry;
}
if (err < 0) {
PBD::error << _("AlsaRawMidiOut: write failed. Terminating Midi Thread.") << endmsg;
break;
}
if ((size_t) err < h.size) {
_DEBUGPRINT("AlsaRawMidiOut: short write\n");
memmove(&data[0], &data[err], err);
h.size -= err;
goto retry;
}
snd_rawmidi_drain (_device);
}
pthread_mutex_unlock (&_notify_mutex);
_DEBUGPRINT("AlsaRawMidiOut: MIDI OUT THREAD STOPPED\n");
return 0;
}
///////////////////////////////////////////////////////////////////////////////
AlsaRawMidiIn::AlsaRawMidiIn (const char *device)
: AlsaRawMidiIO (device, true)
, _event(0,0)
, _first_time(true)
, _unbuffered_bytes(0)
, _total_bytes(0)
, _expected_bytes(0)
, _status_byte(0)
{
}
size_t
AlsaRawMidiIn::recv_event (pframes_t &time, uint8_t *data, size_t &size)
{
const uint32_t read_space = _rb->read_space();
struct MidiEventHeader h(0,0);
if (read_space <= sizeof(MidiEventHeader)) {
return 0;
}
#if 1
// check if event is in current cycle
RingBuffer<uint8_t>::rw_vector vector;
_rb->get_read_vector(&vector);
if (vector.len[0] >= sizeof(MidiEventHeader)) {
memcpy((uint8_t*)&h, vector.buf[0], sizeof(MidiEventHeader));
} else {
if (vector.len[0] > 0) {
memcpy ((uint8_t*)&h, vector.buf[0], vector.len[0]);
}
memcpy (((uint8_t*)&h) + vector.len[0], vector.buf[1], sizeof(MidiEventHeader) - vector.len[0]);
}
if (h.time >= _clock_monotonic + _period_length_us ) {
#ifdef DEBUG_TIMING
printf("AlsaRawMidiIn DEBUG: POSTPONE EVENT TO NEXT CYCLE: %.1f spl\n", ((h.time - _clock_monotonic) / _sample_length_us));
#endif
return 0;
}
_rb->increment_read_idx (sizeof(MidiEventHeader));
#else
if (_rb->read ((uint8_t*)&h, sizeof(MidiEventHeader)) != sizeof(MidiEventHeader)) {
_DEBUGPRINT("AlsaRawMidiIn::recv_event Garbled MIDI EVENT HEADER!!\n");
return 0;
}
#endif
assert (h.size > 0);
if (h.size > size) {
_DEBUGPRINT("AlsaRawMidiIn::recv_event MIDI event too large!\n");
_rb->increment_read_idx (h.size);
return 0;
}
if (_rb->read (&data[0], h.size) != h.size) {
_DEBUGPRINT("AlsaRawMidiIn::recv_event Garbled MIDI EVENT DATA!!\n");
return 0;
}
if (h.time < _clock_monotonic) {
#ifdef DEBUG_TIMING
printf("AlsaRawMidiIn DEBUG: MIDI TIME < 0 %.1f spl\n", ((_clock_monotonic - h.time) / -_sample_length_us));
#endif
time = 0;
} else if (h.time >= _clock_monotonic + _period_length_us ) {
#ifdef DEBUG_TIMING
printf("AlsaRawMidiIn DEBUG: MIDI TIME > PERIOD %.1f spl\n", ((h.time - _clock_monotonic) / _sample_length_us));
#endif
time = _samples_per_period - 1;
} else {
time = floor ((h.time - _clock_monotonic) / _sample_length_us);
}
assert(time < _samples_per_period);
size = h.size;
return h.size;
}
void *
AlsaRawMidiIn::main_process_thread ()
{
_running = true;
while (_running) {
unsigned short revents = 0;
int perr = poll (_pfds, _npfds, 100 /* ms */);
if (perr < 0) {
PBD::error << _("AlsaRawMidiIn: Error polling device. Terminating Midi Thread.") << endmsg;
break;
}
if (perr == 0) {
continue;
}
if (snd_rawmidi_poll_descriptors_revents (_device, _pfds, _npfds, &revents)) {
PBD::error << _("AlsaRawMidiIn: Failed to poll device. Terminating Midi Thread.") << endmsg;
break;
}
if (revents & (POLLERR | POLLHUP | POLLNVAL)) {
PBD::error << _("AlsaRawMidiIn: poll error. Terminating Midi Thread.") << endmsg;
break;
}
if (!(revents & POLLIN)) {
_DEBUGPRINT("AlsaRawMidiOut: POLLIN not ready.\n");
select_sleep (1000);
continue;
}
uint8_t data[MaxAlsaRawEventSize];
uint64_t time = g_get_monotonic_time();
ssize_t err = snd_rawmidi_read (_device, data, sizeof(data));
if ((err == -EAGAIN) || (err == -EWOULDBLOCK)) {
continue;
}
if (err < 0) {
PBD::error << _("AlsaRawMidiIn: read error. Terminating Midi") << endmsg;
break;
}
if (err == 0) {
_DEBUGPRINT("AlsaRawMidiIn: zero read\n");
continue;
}
#if 0
queue_event (time, data, err);
#else
parse_events (time, data, err);
#endif
}
_DEBUGPRINT("AlsaRawMidiIn: MIDI IN THREAD STOPPED\n");
return 0;
}
int
AlsaRawMidiIn::queue_event (const uint64_t time, const uint8_t *data, const size_t size) {
const uint32_t buf_size = sizeof(MidiEventHeader) + size;
_event._pending = false;
if (size == 0) {
return -1;
}
if (_rb->write_space() < buf_size) {
_DEBUGPRINT("AlsaRawMidiIn: ring buffer overflow\n");
return -1;
}
struct MidiEventHeader h (time, size);
_rb->write ((uint8_t*) &h, sizeof(MidiEventHeader));
_rb->write (data, size);
return 0;
}
void
AlsaRawMidiIn::parse_events (const uint64_t time, const uint8_t *data, const size_t size) {
if (_event._pending) {
if (queue_event (_event._time, _parser_buffer, _event._size)) {
return;
}
}
for (size_t i = 0; i < size; ++i) {
if (_first_time && !(data[i] & 0x80)) {
continue;
}
_first_time = false; /// TODO optimize e.g. use fn pointer to different parse_events()
if (process_byte(time, data[i])) {
if (queue_event (_event._time, _parser_buffer, _event._size)) {
return;
}
}
}
}
// based on JackMidiRawInputWriteQueue by Devin Anderson //
bool
AlsaRawMidiIn::process_byte(const uint64_t time, const uint8_t byte)
{
if (byte >= 0xf8) {
// Realtime
if (byte == 0xfd) {
return false;
}
_parser_buffer[0] = byte;
prepare_byte_event(time, byte);
return true;
}
if (byte == 0xf7) {
// Sysex end
if (_status_byte == 0xf0) {
record_byte(byte);
return prepare_buffered_event(time);
}
_total_bytes = 0;
_unbuffered_bytes = 0;
_expected_bytes = 0;
_status_byte = 0;
return false;
}
if (byte >= 0x80) {
// Non-realtime status byte
if (_total_bytes) {
_total_bytes = 0;
_unbuffered_bytes = 0;
}
_status_byte = byte;
switch (byte & 0xf0) {
case 0x80:
case 0x90:
case 0xa0:
case 0xb0:
case 0xe0:
// Note On, Note Off, Aftertouch, Control Change, Pitch Wheel
_expected_bytes = 3;
break;
case 0xc0:
case 0xd0:
// Program Change, Channel Pressure
_expected_bytes = 2;
break;
case 0xf0:
switch (byte) {
case 0xf0:
// Sysex
_expected_bytes = 0;
break;
case 0xf1:
case 0xf3:
// MTC Quarter Frame, Song Select
_expected_bytes = 2;
break;
case 0xf2:
// Song Position
_expected_bytes = 3;
break;
case 0xf4:
case 0xf5:
// Undefined
_expected_bytes = 0;
_status_byte = 0;
return false;
case 0xf6:
// Tune Request
prepare_byte_event(time, byte);
_expected_bytes = 0;
_status_byte = 0;
return true;
}
}
record_byte(byte);
return false;
}
// Data byte
if (! _status_byte) {
// Data bytes without a status will be discarded.
_total_bytes++;
_unbuffered_bytes++;
return false;
}
if (! _total_bytes) {
// Apply running status.
record_byte(_status_byte);
}
record_byte(byte);
return (_total_bytes == _expected_bytes) ? prepare_buffered_event(time) : false;
}