13
0
livetrax/libs/backends/alsa/alsa_rawmidi.cc
Robin Gareus 6968c9f909 Drain ALSA raw-midi buffers after 64 bytes
Very long sequence of *concurrent* events may otherwise be truncated
because the backend requests a buffer-size of 64 bytes via
snd_rawmidi_params_set_buffer_size().
2017-04-09 05:03:19 +02:00

436 lines
10 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 "select_sleep.h"
#include "alsa_rawmidi.h"
#include "pbd/error.h"
#include "pbd/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 std::string &name, const char *device, const bool input)
: AlsaMidiIO()
, _device (0)
{
_name = name;
init (device, input);
}
AlsaRawMidiIO::~AlsaRawMidiIO ()
{
if (_device) {
snd_rawmidi_drain (_device);
snd_rawmidi_close (_device);
_device = 0;
}
}
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);
#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;
}
///////////////////////////////////////////////////////////////////////////////
AlsaRawMidiOut::AlsaRawMidiOut (const std::string &name, const char *device)
: AlsaRawMidiIO (name, device, false)
, AlsaMidiOut ()
{
}
void *
AlsaRawMidiOut::main_process_thread ()
{
_running = true;
pthread_mutex_lock (&_notify_mutex);
unsigned int need_drain = 0;
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) {
if (need_drain > 0) {
snd_rawmidi_drain (_device);
need_drain = 0;
}
pthread_cond_wait (&_notify_ready, &_notify_mutex);
continue;
}
uint64_t now = g_get_monotonic_time();
while (h.time > now + 500) {
if (need_drain > 0) {
snd_rawmidi_drain (_device);
need_drain = 0;
} else {
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 0 // DEBUG -- not rt-safe
printf("TX [%ld | %ld]", h.size, err);
for (size_t i = 0; i < h.size; ++i) {
printf (" %02x", data[i]);
}
printf ("\n");
#endif
if ((err == -EAGAIN)) {
snd_rawmidi_drain (_device);
goto retry;
}
if (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;
}
if ((need_drain += h.size) >= 64) {
snd_rawmidi_drain (_device);
need_drain = 0;
}
}
pthread_mutex_unlock (&_notify_mutex);
_DEBUGPRINT("AlsaRawMidiOut: MIDI OUT THREAD STOPPED\n");
return 0;
}
///////////////////////////////////////////////////////////////////////////////
AlsaRawMidiIn::AlsaRawMidiIn (const std::string &name, const char *device)
: AlsaRawMidiIO (name, device, true)
, AlsaMidiIn ()
, _event(0,0)
, _first_time(true)
, _unbuffered_bytes(0)
, _total_bytes(0)
, _expected_bytes(0)
, _status_byte(0)
{
}
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) {
_event._pending = false;
return AlsaMidiIn::queue_event(time, data, size);
}
void
AlsaRawMidiIn::parse_events (const uint64_t time, const uint8_t *data, const size_t size) {
if (_event._pending) {
_DEBUGPRINT("AlsaRawMidiIn: queue pending event\n");
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) {
_DEBUGPRINT("AlsaRawMidiIn: discarded bogus midi message\n");
#if 0
for (size_t i=0; i < _total_bytes; ++i) {
printf("%02x ", _parser_buffer[i]);
}
printf("\n");
#endif
_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) {
_DEBUGPRINT("AlsaRawMidiIn: apply running status\n");
record_byte(_status_byte);
}
record_byte(byte);
return (_total_bytes == _expected_bytes) ? prepare_buffered_event(time) : false;
}