scummvm/backends/midi/alsa.cpp
2014-02-18 02:39:32 +01:00

505 lines
14 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
// Disable symbol overrides so that we can use system headers.
#define FORBIDDEN_SYMBOL_ALLOW_ALL
#include "common/scummsys.h"
#if defined(USE_ALSA)
#include "common/config-manager.h"
#include "common/error.h"
#include "common/textconsole.h"
#include "common/util.h"
#include "audio/musicplugin.h"
#include "audio/mpu401.h"
#include <alsa/asoundlib.h>
/*
* ALSA sequencer driver
* Mostly cut'n'pasted from Virtual Tiny Keyboard (vkeybd) by Takashi Iwai
* (you really rox, you know?)
*/
#if SND_LIB_MAJOR >= 1 || SND_LIB_MINOR >= 6
#define snd_seq_flush_output(x) snd_seq_drain_output(x)
#define snd_seq_set_client_group(x,name) /*nop */
#define my_snd_seq_open(seqp) snd_seq_open(seqp, "hw", SND_SEQ_OPEN_DUPLEX, 0)
#else
/* SND_SEQ_OPEN_OUT causes oops on early version of ALSA */
#define my_snd_seq_open(seqp) snd_seq_open(seqp, SND_SEQ_OPEN)
#endif
#define perm_ok(pinfo,bits) ((snd_seq_port_info_get_capability(pinfo) & (bits)) == (bits))
static int check_permission(snd_seq_port_info_t *pinfo) {
if (perm_ok(pinfo, SND_SEQ_PORT_CAP_WRITE | SND_SEQ_PORT_CAP_SUBS_WRITE)) {
if (!(snd_seq_port_info_get_capability(pinfo) & SND_SEQ_PORT_CAP_NO_EXPORT))
return 1;
}
return 0;
}
/*
* parse address string
*/
#define ADDR_DELIM ".:"
class MidiDriver_ALSA : public MidiDriver_MPU401 {
public:
MidiDriver_ALSA(int client, int port);
int open();
bool isOpen() const { return _isOpen; }
void close();
void send(uint32 b);
void sysEx(const byte *msg, uint16 length);
private:
void send_event(int do_flush);
bool _isOpen;
snd_seq_event_t ev;
snd_seq_t *seq_handle;
int seq_client, seq_port;
int my_client, my_port;
// The volume controller value of the first MIDI channel
int8 _channel0Volume;
};
MidiDriver_ALSA::MidiDriver_ALSA(int client, int port)
: _isOpen(false), seq_handle(0), seq_client(client), seq_port(port), my_client(0), my_port(0), _channel0Volume(127) {
memset(&ev, 0, sizeof(ev));
}
int MidiDriver_ALSA::open() {
if (_isOpen)
return MERR_ALREADY_OPEN;
_isOpen = true;
if (my_snd_seq_open(&seq_handle) < 0) {
error("Can't open sequencer");
return -1;
}
my_client = snd_seq_client_id(seq_handle);
if (snd_seq_set_client_name(seq_handle, "SCUMMVM") < 0) {
error("Can't set sequencer client name");
}
snd_seq_set_client_group(seq_handle, "input");
// According to http://www.alsa-project.org/~tiwai/alsa-subs.html
// you can set read or write capabilities to allow other clients to
// read or write the port. I don't think we need that, unless maybe
// to be able to record the sound, but I can't get that to work even
// with those capabilities.
my_port = snd_seq_create_simple_port(seq_handle, "SCUMMVM port 0", 0,
SND_SEQ_PORT_TYPE_MIDI_GENERIC | SND_SEQ_PORT_TYPE_APPLICATION);
if (my_port < 0) {
snd_seq_close(seq_handle);
error("Can't create port");
return -1;
}
if (seq_client != SND_SEQ_ADDRESS_SUBSCRIBERS) {
// Subscribe to MIDI port. Prefer one that doesn't already have
// any connections, unless we've forced a port number already.
if (seq_port == -1) {
snd_seq_client_info_t *cinfo;
snd_seq_port_info_t *pinfo;
snd_seq_client_info_alloca(&cinfo);
snd_seq_port_info_alloca(&pinfo);
snd_seq_get_any_client_info(seq_handle, seq_client, cinfo);
int first_port = -1;
int found_port = -1;
snd_seq_port_info_set_client(pinfo, seq_client);
snd_seq_port_info_set_port(pinfo, -1);
while (found_port == -1 && snd_seq_query_next_port(seq_handle, pinfo) >= 0) {
if (check_permission(pinfo)) {
if (first_port == -1)
first_port = snd_seq_port_info_get_port(pinfo);
if (found_port == -1 && snd_seq_port_info_get_write_use(pinfo) == 0)
found_port = snd_seq_port_info_get_port(pinfo);
}
}
if (found_port == -1) {
// Should we abort here? For now, use the first
// available port.
seq_port = first_port;
warning("MidiDriver_ALSA: All ports on client %d (%s) are already in use", seq_client, snd_seq_client_info_get_name(cinfo));
} else {
seq_port = found_port;
}
}
if (snd_seq_connect_to(seq_handle, my_port, seq_client, seq_port) < 0) {
error("Can't subscribe to MIDI port (%d:%d) see README for help", seq_client, seq_port);
}
}
printf("Connected to Alsa sequencer client [%d:%d]\n", seq_client, seq_port);
printf("ALSA client initialized [%d:0]\n", my_client);
return 0;
}
void MidiDriver_ALSA::close() {
if (_isOpen) {
_isOpen = false;
MidiDriver_MPU401::close();
if (seq_handle)
snd_seq_close(seq_handle);
} else
warning("MidiDriver_ALSA: Closing the driver before opening it");
}
void MidiDriver_ALSA::send(uint32 b) {
if (!_isOpen) {
warning("MidiDriver_ALSA: Got event while not open");
return;
}
unsigned int midiCmd[4];
ev.type = SND_SEQ_EVENT_OSS;
midiCmd[3] = (b & 0xFF000000) >> 24;
midiCmd[2] = (b & 0x00FF0000) >> 16;
midiCmd[1] = (b & 0x0000FF00) >> 8;
midiCmd[0] = (b & 0x000000FF);
ev.data.raw32.d[0] = midiCmd[0];
ev.data.raw32.d[1] = midiCmd[1];
ev.data.raw32.d[2] = midiCmd[2];
unsigned char chanID = midiCmd[0] & 0x0F;
switch (midiCmd[0] & 0xF0) {
case 0x80:
snd_seq_ev_set_noteoff(&ev, chanID, midiCmd[1], midiCmd[2]);
send_event(1);
break;
case 0x90:
snd_seq_ev_set_noteon(&ev, chanID, midiCmd[1], midiCmd[2]);
send_event(1);
break;
case 0xA0:
snd_seq_ev_set_keypress(&ev, chanID, midiCmd[1], midiCmd[2]);
send_event(1);
break;
case 0xB0:
/* is it this simple ? Wow... */
snd_seq_ev_set_controller(&ev, chanID, midiCmd[1], midiCmd[2]);
// We save the volume of the first MIDI channel here to utilize it in
// our workaround for broken USB-MIDI cables.
if (chanID == 0 && midiCmd[1] == 0x07)
_channel0Volume = midiCmd[2];
send_event(1);
break;
case 0xC0:
snd_seq_ev_set_pgmchange(&ev, chanID, midiCmd[1]);
send_event(0);
// Send a volume change command to work around a firmware bug in common
// USB-MIDI cables. If the first MIDI command in a USB packet is a
// Cx or Dx command, the second command in the packet is dropped
// somewhere.
send(0x07B0 | (_channel0Volume << 16));
break;
case 0xD0:
snd_seq_ev_set_chanpress(&ev, chanID, midiCmd[1]);
send_event(1);
// Send a volume change command to work around a firmware bug in common
// USB-MIDI cables. If the first MIDI command in a USB packet is a
// Cx or Dx command, the second command in the packet is dropped
// somewhere.
send(0x07B0 | (_channel0Volume << 16));
break;
case 0xE0: {
// long theBend = ((((long)midiCmd[1] + (long)(midiCmd[2] << 7))) - 0x2000) / 4;
// snd_seq_ev_set_pitchbend(&ev, chanID, theBend);
long theBend = ((long)midiCmd[1] + (long)(midiCmd[2] << 7)) - 0x2000;
snd_seq_ev_set_pitchbend(&ev, chanID, theBend);
send_event(1);
} break;
default:
warning("Unknown MIDI Command: %08x", (int)b);
/* I don't know if this works but, well... */
send_event(1);
break;
}
}
void MidiDriver_ALSA::sysEx(const byte *msg, uint16 length) {
if (!_isOpen) {
warning("MidiDriver_ALSA: Got SysEx while not open");
return;
}
unsigned char buf[266];
assert(length + 2 <= ARRAYSIZE(buf));
// Add SysEx frame
buf[0] = 0xF0;
memcpy(buf + 1, msg, length);
buf[length + 1] = 0xF7;
// Send it
snd_seq_ev_set_sysex(&ev, length + 2, &buf);
send_event(1);
}
void MidiDriver_ALSA::send_event(int do_flush) {
snd_seq_ev_set_direct(&ev);
snd_seq_ev_set_source(&ev, my_port);
snd_seq_ev_set_dest(&ev, seq_client, seq_port);
snd_seq_event_output(seq_handle, &ev);
if (do_flush)
snd_seq_flush_output(seq_handle);
}
// Plugin interface
class AlsaDevice {
public:
AlsaDevice(Common::String name, MusicType mt, int client);
Common::String getName();
MusicType getType();
int getClient();
private:
Common::String _name;
MusicType _type;
int _client;
};
typedef Common::List<AlsaDevice> AlsaDevices;
AlsaDevice::AlsaDevice(Common::String name, MusicType mt, int client)
: _name(name), _type(mt), _client(client) {
// Make sure we do not get any trailing spaces to avoid problems when
// storing the name in the configuration file.
_name.trim();
}
Common::String AlsaDevice::getName() {
return _name;
}
MusicType AlsaDevice::getType() {
return _type;
}
int AlsaDevice::getClient() {
return _client;
}
class AlsaMusicPlugin : public MusicPluginObject {
public:
const char *getName() const {
return "ALSA";
}
const char *getId() const {
return "alsa";
}
AlsaDevices getAlsaDevices() const;
MusicDevices getDevices() const;
Common::Error createInstance(MidiDriver **mididriver, MidiDriver::DeviceHandle = 0) const;
private:
static int parse_addr(const char *arg, int *client, int *port);
};
AlsaDevices AlsaMusicPlugin::getAlsaDevices() const {
AlsaDevices devices;
snd_seq_t *seq_handle;
if (my_snd_seq_open(&seq_handle) < 0)
return devices; // can't open sequencer
snd_seq_client_info_t *cinfo;
snd_seq_client_info_alloca(&cinfo);
snd_seq_port_info_t *pinfo;
snd_seq_port_info_alloca(&pinfo);
snd_seq_client_info_set_client(cinfo, -1);
while (snd_seq_query_next_client(seq_handle, cinfo) >= 0) {
bool found_valid_port = false;
/* reset query info */
snd_seq_port_info_set_client(pinfo, snd_seq_client_info_get_client(cinfo));
snd_seq_port_info_set_port(pinfo, -1);
while (!found_valid_port && snd_seq_query_next_port(seq_handle, pinfo) >= 0) {
if (check_permission(pinfo)) {
found_valid_port = true;
const char *name = snd_seq_client_info_get_name(cinfo);
// TODO: Can we figure out the appropriate music type?
MusicType type = MT_GM;
int client = snd_seq_client_info_get_client(cinfo);
devices.push_back(AlsaDevice(name, type, client));
}
}
}
snd_seq_close(seq_handle);
return devices;
}
MusicDevices AlsaMusicPlugin::getDevices() const {
MusicDevices devices;
AlsaDevices::iterator d;
AlsaDevices alsaDevices = getAlsaDevices();
// Since the default behavior is to use the first device in the list,
// try to put something sensible there. We used to have 17:0 and 65:0
// as defaults.
for (d = alsaDevices.begin(); d != alsaDevices.end();) {
const int client = d->getClient();
if (client == 17 || client == 65) {
devices.push_back(MusicDevice(this, d->getName(), d->getType()));
d = alsaDevices.erase(d);
} else {
++d;
}
}
// 128:0 is probably TiMidity, or something like that, so that's
// probably a good second choice.
for (d = alsaDevices.begin(); d != alsaDevices.end();) {
if (d->getClient() == 128) {
devices.push_back(MusicDevice(this, d->getName(), d->getType()));
d = alsaDevices.erase(d);
} else {
++d;
}
}
// Add the remaining devices in the order they were found.
for (d = alsaDevices.begin(); d != alsaDevices.end(); ++d)
devices.push_back(MusicDevice(this, d->getName(), d->getType()));
return devices;
}
Common::Error AlsaMusicPlugin::createInstance(MidiDriver **mididriver, MidiDriver::DeviceHandle dev) const {
bool found = false;
int seq_client, seq_port;
const char *var = NULL;
// TODO: Upgrade from old alsa_port setting. This probably isn't the
// right place to do that, though.
if (ConfMan.hasKey("alsa_port")) {
warning("AlsaMusicPlugin: Found old 'alsa_port' setting, which will be ignored");
}
// The SCUMMVM_PORT environment variable can still be used to override
// any config setting.
var = getenv("SCUMMVM_PORT");
if (var) {
warning("AlsaMusicPlugin: SCUMMVM_PORT environment variable overrides config settings");
if (parse_addr(var, &seq_client, &seq_port) >= 0) {
found = true;
} else {
warning("AlsaMusicPlugin: Invalid port %s, using config settings instead", var);
}
}
// Try to match the setting to an available ALSA device.
if (!found && dev) {
AlsaDevices alsaDevices = getAlsaDevices();
for (AlsaDevices::iterator d = alsaDevices.begin(); d != alsaDevices.end(); ++d) {
MusicDevice device(this, d->getName(), d->getType());
if (device.getCompleteId().equals(MidiDriver::getDeviceString(dev, MidiDriver::kDeviceId))) {
found = true;
seq_client = d->getClient();
seq_port = -1;
break;
}
}
}
// Still nothing? Try a sensible default.
if (!found) {
// TODO: What's a sensible default anyway? And exactly when do
// we get to this case?
warning("AlsaMusicPlugin: Using 17:0 as default ALSA port");
seq_client = 17;
seq_port = 0;
}
*mididriver = new MidiDriver_ALSA(seq_client, seq_port);
return Common::kNoError;
}
int AlsaMusicPlugin::parse_addr(const char *arg, int *client, int *port) {
const char *p;
if (isdigit(*arg)) {
if ((p = strpbrk(arg, ADDR_DELIM)) == NULL)
return -1;
*client = atoi(arg);
*port = atoi(p + 1);
} else {
if (*arg == 's' || *arg == 'S') {
*client = SND_SEQ_ADDRESS_SUBSCRIBERS;
*port = 0;
} else
return -1;
}
return 0;
}
//#if PLUGIN_ENABLED_DYNAMIC(ALSA)
//REGISTER_PLUGIN_DYNAMIC(ALSA, PLUGIN_TYPE_MUSIC, AlsaMusicPlugin);
//#else
REGISTER_PLUGIN_STATIC(ALSA, PLUGIN_TYPE_MUSIC, AlsaMusicPlugin);
//#endif
#endif