oper_alsa.c

/*
 * operator for ALSA sequencer
 *
 * Virtual Tiny Keyboard
 *
 * Copyright (c) 1997-2000 by Takashi Iwai
 *
 * 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 "vkb.h"
#include <unistd.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#ifdef USE_OLD_ALSA
#include <sys/asoundlib.h>
#else
#include <alsa/asoundlib.h>
#endif

#if SND_LIB_MAJOR > 0 || 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_OUTPUT, 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

/*
 * functions
 */
static int seq_open(Tcl_Interp *ip, void **private_return);
static void seq_close(Tcl_Interp *ip, void *private);
static void note_on(Tcl_Interp *ip, void *private, int note, int vel);
static void note_off(Tcl_Interp *ip, void *private, int note, int vel);
static void control(Tcl_Interp *ip, void *private, int type, int val);
static void program(Tcl_Interp *ip, void *private, int bank, int type);
static void bender(Tcl_Interp *ip, void *private, int bend);
static void chorus_mode(Tcl_Interp *ip, void *private, int mode);
static void reverb_mode(Tcl_Interp *ip, void *private, int mode);
static void send_event(int do_flush);


#define DEFAULT_NAME	"Virtual Keyboard"

/*
 * definition of device information
 */

static vkb_oper_t alsa_oper = {
	seq_open,
	seq_close,
	program,
	note_on,
	note_off,
	control,
	bender,
	chorus_mode,
	reverb_mode,
};

static vkb_optarg_t alsa_opts[] = {
	{"addr", "subscriber", "--addr client:port or 'subscriber' : ALSA sequencer destination"},
	{"name", DEFAULT_NAME, "--name string : use the specified string as client/port names"},
	{"bankmsb", "0", "--bankmsb 0 or 1: pass the bank selection only to CC#0"},
#ifdef HAVE_LASH	
	{"lash", "no", "--lash <yes|no> : support LASH (default = no)"},
#endif
	{NULL},
};

vkb_devinfo_t alsa_devinfo = {
	"alsa",		/* device id */
	"ALSA sequencer",	/* name */
	0,		/* delayed open */
	&alsa_oper,	/* operators */
	alsa_opts,	/* command line options */
};

/*
 */

static snd_seq_t *seq_handle = NULL;
static int my_client, my_port;
static int seq_client, seq_port;
static int chan_no;
static int bankmsb;

#ifdef HAVE_LASH	
static lash_client_t * lash_client = NULL;
#endif

/*
 * parse address string
 */

#define ADDR_DELIM	".:"

static int parse_addr(const char *arg, int *client, int *port)
{
	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;
}


/*
 * open device
 */

static int
seq_open(Tcl_Interp *ip, void **private_return)
{
	const char *var, *name;
	unsigned int caps;

	/* copy from Tcl variables */
	if ((var = Tcl_GetVar2(ip, "optvar", "addr", TCL_GLOBAL_ONLY)) != NULL) {
		if (parse_addr(var, &seq_client, &seq_port) < 0) {
			vkb_error(ip, "invalid argument --addr %s\n", var);
			return 0;
		}
	}
	
	if (my_snd_seq_open(&seq_handle) < 0) {
		vkb_error(ip, "can't open sequencer device");
		return 0;
	}

	/* get my client id */
	my_client = snd_seq_client_id(seq_handle);
	
	/* tell the lash server our client id */
#ifdef HAVE_LASH
	if ((var = Tcl_GetVar2(ip, "optvar", "lash", TCL_GLOBAL_ONLY)) != NULL) {
		if (*var == 'y' || *var == 'Y' || *var == '1') {
			lash_client = lash_init (lash_args,
					       "vkeybd",
					       my_client, LASH_PROTOCOL_VERSION);
			if (lash_enabled (lash_client)) {
				lash_event_t * event;
				unsigned char id[2];
				event = lash_event_new_with_type (LASH_Alsa_Client_ID);
				id[0] = snd_seq_client_id (seq_handle);
				id[1] = '\0';
				lash_event_set_string (event, id);
				lash_send_event (lash_client, event);
			}
		}
	}
#endif /* HAVE_LASH */
 
	if ((var = Tcl_GetVar2(ip, "optvar", "bankmsb", TCL_GLOBAL_ONLY)) != NULL) {
		if (!strcmp(var, "1"))
			bankmsb = 1;
	}

	/* set client info */
	if ((var = Tcl_GetVar2(ip, "optvar", "name", TCL_GLOBAL_ONLY)) != NULL)
		snd_seq_set_client_name(seq_handle, var);
	else
		snd_seq_set_client_name(seq_handle, DEFAULT_NAME);
	snd_seq_set_client_group(seq_handle, "input");

	/* create port */
	caps = SND_SEQ_PORT_CAP_READ;
	if (seq_client == SND_SEQ_ADDRESS_SUBSCRIBERS)
		caps |= SND_SEQ_PORT_CAP_SUBS_READ;
	if ((var = Tcl_GetVar2(ip, "optvar", "name", TCL_GLOBAL_ONLY)) != NULL)
		name = var;
	else
		name = DEFAULT_NAME;
	my_port = snd_seq_create_simple_port(seq_handle, name, caps,
					     SND_SEQ_PORT_TYPE_MIDI_GENERIC |
					     SND_SEQ_PORT_TYPE_APPLICATION);
	if (my_port < 0) {
		vkb_error(ip, "can't create port\n");
		snd_seq_close(seq_handle);
		return 0;
	}

	if (seq_client != SND_SEQ_ADDRESS_SUBSCRIBERS) {
		/* subscribe to MIDI port */
		if (
#ifdef HAVE_LASH
		    !lash_enabled (lash_client) &&
#endif
		    snd_seq_connect_to(seq_handle, my_port, seq_client, seq_port) < 0) {
			vkb_error(ip, "can't subscribe to MIDI port (%d:%d)\n", seq_client, seq_port);
			snd_seq_close(seq_handle);
			return 0;
		}
	}

	{
		char tmp[128];
		sprintf(tmp, "wm title . \"Virtual Keyboard ver.1.9 \\[%d:%d\\]\"", my_client, my_port);
		Tcl_Eval(ip, tmp);
	}

	return 1;
}


static void
seq_close(Tcl_Interp *ip, void *private)
{
	snd_seq_close(seq_handle);
}


/*
 */

static snd_seq_event_t ev;

static void
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);
}

static void
note_on(Tcl_Interp *ip, void *private, int note, int vel)
{
	snd_seq_ev_set_noteon(&ev, chan_no, note, vel);
	send_event(1);
}

static void
note_off(Tcl_Interp *ip, void *private, int note, int vel)
{
	snd_seq_ev_set_noteoff(&ev, chan_no, note, vel);
	send_event(1);
}

static void
control(Tcl_Interp *ip, void *private, int type, int val)
{
	snd_seq_ev_set_controller(&ev, chan_no, type, val);
	send_event(1);
}

static void
program(Tcl_Interp *ip, void *private, int bank, int preset)
{
	vkb_get_int(ip, "channel", &chan_no);
	if (bank == 128)
		vkb_get_int(ip, "drum", &chan_no);
	else if (bankmsb) {
		snd_seq_ev_set_controller(&ev, chan_no, 0, bank);
		send_event(0);
	} else {
		snd_seq_ev_set_controller(&ev, chan_no, 0, (bank >> 7) & 127);
		send_event(0);
		snd_seq_ev_set_controller(&ev, chan_no, 32, bank & 127);
		send_event(0);
	}

	snd_seq_ev_set_pgmchange(&ev, chan_no, preset);
	send_event(1);
}

static void
bender(Tcl_Interp *ip, void *private, int bend)
{
	snd_seq_ev_set_pitchbend(&ev, chan_no, bend);
	send_event(1);
}

static void
chorus_mode(Tcl_Interp *ip, void *private, int mode)
{
	static unsigned char sysex[11] = {
		0xf0, 0x41, 0x10, 0x42, 0x12, 0x40, 0x01, 0x38, 0, 0, 0xf7,
	};
	sysex[8] = mode;
	snd_seq_ev_set_sysex(&ev, 11, sysex);
	send_event(1);
	snd_seq_ev_set_fixed(&ev); /* reset */
}

static void
reverb_mode(Tcl_Interp *ip, void *private, int mode)
{
	static unsigned char sysex[11] = {
		0xf0, 0x41, 0x10, 0x42, 0x12, 0x40, 0x01, 0x30, 0, 0, 0xf7,
	};
	sysex[8] = mode;
	snd_seq_ev_set_sysex(&ev, 11, sysex);
	send_event(1);
	snd_seq_ev_set_fixed(&ev); /* reset */
}