comparison plugin/api/dssi_alsa_compat.c @ 0:da6937383da8

initial import
author Chris Cannam
date Tue, 10 Jan 2006 16:33:16 +0000
parents
children d7f3dfe6f9a4
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-1:000000000000 0:da6937383da8
1 /* DSSI ALSA compatibility library
2 *
3 * This library provides for non-ALSA systems the ALSA snd_seq_event_t handling
4 * necessary to compile and run DSSI. It was extracted from alsa-lib 1.0.8.
5 *
6 * See ./alsa/README for more information.
7 */
8
9 #include <stdlib.h>
10 #include <errno.h>
11
12 #include "alsa/asoundef.h"
13 #include "alsa/sound/asequencer.h"
14 #include "alsa/seq.h"
15 #include "alsa/seq_event.h"
16 #include "alsa/seq_midi_event.h"
17
18 /**
19 * \file seq/seq_event.c
20 * \brief Sequencer Event Types
21 * \author Takashi Iwai <tiwai@suse.de>
22 * \date 2001
23 */
24
25 #define FIXED_EV(x) (_SND_SEQ_TYPE(SND_SEQ_EVFLG_FIXED) | _SND_SEQ_TYPE(x))
26
27 /** Event types conversion array */
28 const unsigned int snd_seq_event_types[256] = {
29 [SND_SEQ_EVENT_SYSTEM ... SND_SEQ_EVENT_RESULT]
30 = FIXED_EV(SND_SEQ_EVFLG_RESULT),
31 [SND_SEQ_EVENT_NOTE]
32 = FIXED_EV(SND_SEQ_EVFLG_NOTE) | _SND_SEQ_TYPE_OPT(SND_SEQ_EVFLG_NOTE_TWOARG),
33 [SND_SEQ_EVENT_NOTEON ... SND_SEQ_EVENT_KEYPRESS]
34 = FIXED_EV(SND_SEQ_EVFLG_NOTE),
35 [SND_SEQ_EVENT_CONTROLLER ... SND_SEQ_EVENT_REGPARAM]
36 = FIXED_EV(SND_SEQ_EVFLG_CONTROL),
37 [SND_SEQ_EVENT_START ... SND_SEQ_EVENT_STOP]
38 = FIXED_EV(SND_SEQ_EVFLG_QUEUE),
39 [SND_SEQ_EVENT_SETPOS_TICK]
40 = FIXED_EV(SND_SEQ_EVFLG_QUEUE) | _SND_SEQ_TYPE_OPT(SND_SEQ_EVFLG_QUEUE_TICK),
41 [SND_SEQ_EVENT_SETPOS_TIME]
42 = FIXED_EV(SND_SEQ_EVFLG_QUEUE) | _SND_SEQ_TYPE_OPT(SND_SEQ_EVFLG_QUEUE_TIME),
43 [SND_SEQ_EVENT_TEMPO ... SND_SEQ_EVENT_SYNC_POS]
44 = FIXED_EV(SND_SEQ_EVFLG_QUEUE) | _SND_SEQ_TYPE_OPT(SND_SEQ_EVFLG_QUEUE_VALUE),
45 [SND_SEQ_EVENT_TUNE_REQUEST ... SND_SEQ_EVENT_SENSING]
46 = FIXED_EV(SND_SEQ_EVFLG_NONE),
47 [SND_SEQ_EVENT_ECHO ... SND_SEQ_EVENT_OSS]
48 = FIXED_EV(SND_SEQ_EVFLG_RAW) | FIXED_EV(SND_SEQ_EVFLG_SYSTEM),
49 [SND_SEQ_EVENT_CLIENT_START ... SND_SEQ_EVENT_PORT_CHANGE]
50 = FIXED_EV(SND_SEQ_EVFLG_MESSAGE),
51 [SND_SEQ_EVENT_PORT_SUBSCRIBED ... SND_SEQ_EVENT_PORT_UNSUBSCRIBED]
52 = FIXED_EV(SND_SEQ_EVFLG_CONNECTION),
53 [SND_SEQ_EVENT_SAMPLE ... SND_SEQ_EVENT_SAMPLE_PRIVATE1]
54 = FIXED_EV(SND_SEQ_EVFLG_SAMPLE),
55 [SND_SEQ_EVENT_USR0 ... SND_SEQ_EVENT_USR9]
56 = FIXED_EV(SND_SEQ_EVFLG_RAW) | FIXED_EV(SND_SEQ_EVFLG_USERS),
57 [SND_SEQ_EVENT_INSTR_BEGIN ... SND_SEQ_EVENT_INSTR_CHANGE]
58 = _SND_SEQ_TYPE(SND_SEQ_EVFLG_INSTR) | _SND_SEQ_TYPE(SND_SEQ_EVFLG_VARUSR),
59 [SND_SEQ_EVENT_SYSEX ... SND_SEQ_EVENT_BOUNCE]
60 = _SND_SEQ_TYPE(SND_SEQ_EVFLG_VARIABLE),
61 [SND_SEQ_EVENT_USR_VAR0 ... SND_SEQ_EVENT_USR_VAR4]
62 = _SND_SEQ_TYPE(SND_SEQ_EVFLG_VARIABLE) | _SND_SEQ_TYPE(SND_SEQ_EVFLG_USERS),
63 [SND_SEQ_EVENT_NONE]
64 = FIXED_EV(SND_SEQ_EVFLG_NONE),
65 };
66
67 /**
68 * \file seq/seq_midi_event.c
69 * \brief MIDI byte <-> sequencer event coder
70 * \author Takashi Iwai <tiwai@suse.de>
71 * \author Jaroslav Kysela <perex@suse.cz>
72 * \date 2000-2001
73 */
74
75 /*
76 * MIDI byte <-> sequencer event coder
77 *
78 * Copyright (C) 1998,99,2000 Takashi Iwai <tiwai@suse.de>,
79 * Jaroslav Kysela <perex@suse.cz>
80 *
81 *
82 * This library is free software; you can redistribute it and/or modify
83 * it under the terms of the GNU Lesser General Public License as
84 * published by the Free Software Foundation; either version 2.1 of
85 * the License, or (at your option) any later version.
86 *
87 * This program is distributed in the hope that it will be useful,
88 * but WITHOUT ANY WARRANTY; without even the implied warranty of
89 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
90 * GNU Lesser General Public License for more details.
91 *
92 * You should have received a copy of the GNU Lesser General Public
93 * License along with this library; if not, write to the Free Software
94 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
95 */
96
97 /* midi status */
98 struct snd_midi_event {
99 size_t qlen; /* queue length */
100 size_t read; /* chars read */
101 int type; /* current event type */
102 unsigned char lastcmd;
103 unsigned char nostat;
104 size_t bufsize;
105 unsigned char *buf; /* input buffer */
106 };
107
108
109 /* queue type */
110 /* from 0 to 7 are normal commands (note off, on, etc.) */
111 #define ST_NOTEOFF 0
112 #define ST_NOTEON 1
113 #define ST_SPECIAL 8
114 #define ST_SYSEX ST_SPECIAL
115 /* from 8 to 15 are events for 0xf0-0xf7 */
116
117
118 /* status event types */
119 typedef void (*event_encode_t)(snd_midi_event_t *dev, snd_seq_event_t *ev);
120 typedef void (*event_decode_t)(const snd_seq_event_t *ev, unsigned char *buf);
121
122 /*
123 * prototypes
124 */
125 static void note_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
126 static void one_param_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
127 static void pitchbend_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
128 static void two_param_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
129 static void one_param_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
130 static void songpos_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
131 static void note_decode(const snd_seq_event_t *ev, unsigned char *buf);
132 static void one_param_decode(const snd_seq_event_t *ev, unsigned char *buf);
133 static void pitchbend_decode(const snd_seq_event_t *ev, unsigned char *buf);
134 static void two_param_decode(const snd_seq_event_t *ev, unsigned char *buf);
135 static void songpos_decode(const snd_seq_event_t *ev, unsigned char *buf);
136
137 /*
138 * event list
139 */
140 static struct status_event_list_t {
141 int event;
142 int qlen;
143 event_encode_t encode;
144 event_decode_t decode;
145 } status_event[] = {
146 /* 0x80 - 0xf0 */
147 {SND_SEQ_EVENT_NOTEOFF, 2, note_event, note_decode},
148 {SND_SEQ_EVENT_NOTEON, 2, note_event, note_decode},
149 {SND_SEQ_EVENT_KEYPRESS, 2, note_event, note_decode},
150 {SND_SEQ_EVENT_CONTROLLER, 2, two_param_ctrl_event, two_param_decode},
151 {SND_SEQ_EVENT_PGMCHANGE, 1, one_param_ctrl_event, one_param_decode},
152 {SND_SEQ_EVENT_CHANPRESS, 1, one_param_ctrl_event, one_param_decode},
153 {SND_SEQ_EVENT_PITCHBEND, 2, pitchbend_ctrl_event, pitchbend_decode},
154 {SND_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xf0 */
155 /* 0xf0 - 0xff */
156 {SND_SEQ_EVENT_SYSEX, 1, NULL, NULL}, /* sysex: 0xf0 */
157 {SND_SEQ_EVENT_QFRAME, 1, one_param_event, one_param_decode}, /* 0xf1 */
158 {SND_SEQ_EVENT_SONGPOS, 2, songpos_event, songpos_decode}, /* 0xf2 */
159 {SND_SEQ_EVENT_SONGSEL, 1, one_param_event, one_param_decode}, /* 0xf3 */
160 {SND_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xf4 */
161 {SND_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xf5 */
162 {SND_SEQ_EVENT_TUNE_REQUEST, 0, NULL, NULL}, /* 0xf6 */
163 {SND_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xf7 */
164 {SND_SEQ_EVENT_CLOCK, 0, NULL, NULL}, /* 0xf8 */
165 {SND_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xf9 */
166 {SND_SEQ_EVENT_START, 0, NULL, NULL}, /* 0xfa */
167 {SND_SEQ_EVENT_CONTINUE, 0, NULL, NULL}, /* 0xfb */
168 {SND_SEQ_EVENT_STOP, 0, NULL, NULL}, /* 0xfc */
169 {SND_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xfd */
170 {SND_SEQ_EVENT_SENSING, 0, NULL, NULL}, /* 0xfe */
171 {SND_SEQ_EVENT_RESET, 0, NULL, NULL}, /* 0xff */
172 };
173
174 #ifdef UNNEEDED_BY_DSSI
175 static int extra_decode_ctrl14(snd_midi_event_t *dev, unsigned char *buf, int len, const snd_seq_event_t *ev);
176 static int extra_decode_xrpn(snd_midi_event_t *dev, unsigned char *buf, int count, const snd_seq_event_t *ev);
177
178 static struct extra_event_list_t {
179 int event;
180 int (*decode)(snd_midi_event_t *dev, unsigned char *buf, int len, const snd_seq_event_t *ev);
181 } extra_event[] = {
182 {SND_SEQ_EVENT_CONTROL14, extra_decode_ctrl14},
183 {SND_SEQ_EVENT_NONREGPARAM, extra_decode_xrpn},
184 {SND_SEQ_EVENT_REGPARAM, extra_decode_xrpn},
185 };
186
187 #define numberof(ary) (sizeof(ary)/sizeof(ary[0]))
188 #endif /* UNNEEDED_BY_DSSI */
189
190 /**
191 * \brief Initialize MIDI event parser
192 * \param bufsize buffer size for MIDI message
193 * \param rdev allocated MIDI event parser
194 * \return 0 on success otherwise a negative error code
195 *
196 * Allocates and initializes MIDI event parser.
197 */
198 int snd_midi_event_new(size_t bufsize, snd_midi_event_t **rdev)
199 {
200 snd_midi_event_t *dev;
201
202 *rdev = NULL;
203 dev = (snd_midi_event_t *)calloc(1, sizeof(snd_midi_event_t));
204 if (dev == NULL)
205 return -ENOMEM;
206 if (bufsize > 0) {
207 dev->buf = malloc(bufsize);
208 if (dev->buf == NULL) {
209 free(dev);
210 return -ENOMEM;
211 }
212 }
213 dev->bufsize = bufsize;
214 dev->lastcmd = 0xff;
215 *rdev = dev;
216 return 0;
217 }
218
219 /**
220 * \brief Free MIDI event parser
221 * \param rdev MIDI event parser
222 * \return 0 on success otherwise a negative error code
223 *
224 * Frees MIDI event parser.
225 */
226 void snd_midi_event_free(snd_midi_event_t *dev)
227 {
228 if (dev != NULL) {
229 if (dev->buf)
230 free(dev->buf);
231 free(dev);
232 }
233 }
234
235 #ifdef UNNEEDED_BY_DSSI
236 /**
237 * \brief Enable/disable MIDI command merging
238 * \param dev MIDI event parser
239 * \param on 0 - enable MIDI command merging, 1 - always pass the command
240 *
241 * Enable/disable MIDI command merging
242 */
243 void snd_midi_event_no_status(snd_midi_event_t *dev, int on)
244 {
245 dev->nostat = on ? 1 : 0;
246 }
247 #endif /* UNNEEDED_BY_DSSI */
248
249 /*
250 * initialize record
251 */
252 inline static void reset_encode(snd_midi_event_t *dev)
253 {
254 dev->read = 0;
255 dev->qlen = 0;
256 dev->type = 0;
257 }
258
259 /**
260 * \brief Reset MIDI encode parser
261 * \param dev MIDI event parser
262 * \return 0 on success otherwise a negative error code
263 *
264 * Resets MIDI encode parser
265 */
266 void snd_midi_event_reset_encode(snd_midi_event_t *dev)
267 {
268 reset_encode(dev);
269 }
270
271 #ifdef UNNEEDED_BY_DSSI
272 /**
273 * \brief Reset MIDI decode parser
274 * \param dev MIDI event parser
275 * \return 0 on success otherwise a negative error code
276 *
277 * Resets MIDI decode parser
278 */
279 void snd_midi_event_reset_decode(snd_midi_event_t *dev)
280 {
281 dev->lastcmd = 0xff;
282 }
283
284 /**
285 * \brief Initializes MIDI parsers
286 * \param dev MIDI event parser
287 * \return 0 on success otherwise a negative error code
288 *
289 * Initializes MIDI parsers (both encode and decode)
290 */
291 void snd_midi_event_init(snd_midi_event_t *dev)
292 {
293 snd_midi_event_reset_encode(dev);
294 snd_midi_event_reset_decode(dev);
295 }
296
297 /**
298 * \brief Resize MIDI message (event) buffer
299 * \param dev MIDI event parser
300 * \param bufsize new requested buffer size
301 * \return 0 on success otherwise a negative error code
302 *
303 * Resizes MIDI message (event) buffer.
304 */
305 int snd_midi_event_resize_buffer(snd_midi_event_t *dev, size_t bufsize)
306 {
307 unsigned char *new_buf, *old_buf;
308
309 if (bufsize == dev->bufsize)
310 return 0;
311 new_buf = malloc(bufsize);
312 if (new_buf == NULL)
313 return -ENOMEM;
314 old_buf = dev->buf;
315 dev->buf = new_buf;
316 dev->bufsize = bufsize;
317 reset_encode(dev);
318 if (old_buf)
319 free(old_buf);
320 return 0;
321 }
322 #endif /* UNNEEDED_BY_DSSI */
323
324 /**
325 * \brief Read bytes and encode to sequencer event if finished
326 * \param dev MIDI event parser
327 * \param buf MIDI byte stream
328 * \param count count of bytes of MIDI byte stream to encode
329 * \param ev Result - sequencer event
330 * \return count of encoded bytes otherwise a negative error code
331 *
332 * Read bytes and encode to sequencer event if finished.
333 * If complete sequencer event is available, ev->type is not
334 * equal to #SND_SEQ_EVENT_NONE.
335 */
336 long snd_midi_event_encode(snd_midi_event_t *dev, const unsigned char *buf, long count, snd_seq_event_t *ev)
337 {
338 long result = 0;
339 int rc;
340
341 ev->type = SND_SEQ_EVENT_NONE;
342
343 while (count-- > 0) {
344 rc = snd_midi_event_encode_byte(dev, *buf++, ev);
345 result++;
346 if (rc < 0)
347 return rc;
348 else if (rc > 0)
349 return result;
350 }
351
352 return result;
353 }
354
355 /**
356 * \brief Read one byte and encode to sequencer event if finished
357 * \param dev MIDI event parser
358 * \param c a byte of MIDI stream
359 * \param ev Result - sequencer event
360 * \return 1 - sequencer event is completed, 0 - next byte is required for completion, otherwise a negative error code
361 *
362 * Read byte and encode to sequencer event if finished.
363 */
364 int snd_midi_event_encode_byte(snd_midi_event_t *dev, int c, snd_seq_event_t *ev)
365 {
366 int rc = 0;
367
368 c &= 0xff;
369
370 if (c >= MIDI_CMD_COMMON_CLOCK) {
371 /* real-time event */
372 ev->type = status_event[ST_SPECIAL + c - 0xf0].event;
373 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
374 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED;
375 return 1;
376 }
377
378 if (dev->qlen > 0) {
379 /* rest of command */
380 dev->buf[dev->read++] = c;
381 if (dev->type != ST_SYSEX)
382 dev->qlen--;
383 } else {
384 /* new command */
385 dev->read = 1;
386 if (c & 0x80) {
387 dev->buf[0] = c;
388 if ((c & 0xf0) == 0xf0) /* special events */
389 dev->type = (c & 0x0f) + ST_SPECIAL;
390 else
391 dev->type = (c >> 4) & 0x07;
392 dev->qlen = status_event[dev->type].qlen;
393 } else {
394 /* process this byte as argument */
395 dev->buf[dev->read++] = c;
396 dev->qlen = status_event[dev->type].qlen - 1;
397 }
398 }
399 if (dev->qlen == 0) {
400 ev->type = status_event[dev->type].event;
401 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
402 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED;
403 if (status_event[dev->type].encode) /* set data values */
404 status_event[dev->type].encode(dev, ev);
405 rc = 1;
406 } else if (dev->type == ST_SYSEX) {
407 if (c == MIDI_CMD_COMMON_SYSEX_END ||
408 dev->read >= dev->bufsize) {
409 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
410 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_VARIABLE;
411 ev->type = SNDRV_SEQ_EVENT_SYSEX;
412 ev->data.ext.len = dev->read;
413 ev->data.ext.ptr = dev->buf;
414 if (c != MIDI_CMD_COMMON_SYSEX_END)
415 dev->read = 0; /* continue to parse */
416 else
417 reset_encode(dev); /* all parsed */
418 rc = 1;
419 }
420 }
421
422 return rc;
423 }
424
425 /* encode note event */
426 static void note_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
427 {
428 ev->data.note.channel = dev->buf[0] & 0x0f;
429 ev->data.note.note = dev->buf[1];
430 ev->data.note.velocity = dev->buf[2];
431 }
432
433 /* encode one parameter controls */
434 static void one_param_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
435 {
436 ev->data.control.channel = dev->buf[0] & 0x0f;
437 ev->data.control.value = dev->buf[1];
438 }
439
440 /* encode pitch wheel change */
441 static void pitchbend_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
442 {
443 ev->data.control.channel = dev->buf[0] & 0x0f;
444 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1] - 8192;
445 }
446
447 /* encode midi control change */
448 static void two_param_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
449 {
450 ev->data.control.channel = dev->buf[0] & 0x0f;
451 ev->data.control.param = dev->buf[1];
452 ev->data.control.value = dev->buf[2];
453 }
454
455 /* encode one parameter value*/
456 static void one_param_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
457 {
458 ev->data.control.value = dev->buf[1];
459 }
460
461 /* encode song position */
462 static void songpos_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
463 {
464 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1];
465 }
466
467 #ifdef UNNEEDED_BY_DSSI
468 /**
469 * \brief Decode sequencer event to MIDI byte stream
470 * \param dev MIDI event parser
471 * \param buf Result - MIDI byte stream
472 * \param count Available bytes in MIDI byte stream
473 * \param ev Event to decode
474 * \return count of decoded bytes otherwise a negative error code
475 *
476 * Decode sequencer event to MIDI byte stream.
477 */
478 long snd_midi_event_decode(snd_midi_event_t *dev, unsigned char *buf, long count, const snd_seq_event_t *ev)
479 {
480 int cmd;
481 long qlen;
482 unsigned int type;
483
484 if (ev->type == SNDRV_SEQ_EVENT_NONE)
485 return -ENOENT;
486
487 for (type = 0; type < numberof(status_event); type++) {
488 if (ev->type == status_event[type].event)
489 goto __found;
490 }
491 for (type = 0; type < numberof(extra_event); type++) {
492 if (ev->type == extra_event[type].event)
493 return extra_event[type].decode(dev, buf, count, ev);
494 }
495 return -ENOENT;
496
497 __found:
498 if (type >= ST_SPECIAL)
499 cmd = 0xf0 + (type - ST_SPECIAL);
500 else
501 /* data.note.channel and data.control.channel is identical */
502 cmd = 0x80 | (type << 4) | (ev->data.note.channel & 0x0f);
503
504
505 if (cmd == MIDI_CMD_COMMON_SYSEX) {
506 qlen = ev->data.ext.len;
507 if (count < qlen)
508 return -ENOMEM;
509 switch (ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) {
510 case SNDRV_SEQ_EVENT_LENGTH_FIXED:
511 return -EINVAL; /* invalid event */
512 }
513 memcpy(buf, ev->data.ext.ptr, qlen);
514 return qlen;
515 } else {
516 unsigned char xbuf[4];
517
518 if ((cmd & 0xf0) == 0xf0 || dev->lastcmd != cmd || dev->nostat) {
519 dev->lastcmd = cmd;
520 xbuf[0] = cmd;
521 if (status_event[type].decode)
522 status_event[type].decode(ev, xbuf + 1);
523 qlen = status_event[type].qlen + 1;
524 } else {
525 if (status_event[type].decode)
526 status_event[type].decode(ev, xbuf + 0);
527 qlen = status_event[type].qlen;
528 }
529 if (count < qlen)
530 return -ENOMEM;
531 memcpy(buf, xbuf, qlen);
532 return qlen;
533 }
534 }
535 #endif /* UNNEEDED_BY_DSSI */
536
537 /* decode note event */
538 static void note_decode(const snd_seq_event_t *ev, unsigned char *buf)
539 {
540 buf[0] = ev->data.note.note & 0x7f;
541 buf[1] = ev->data.note.velocity & 0x7f;
542 }
543
544 /* decode one parameter controls */
545 static void one_param_decode(const snd_seq_event_t *ev, unsigned char *buf)
546 {
547 buf[0] = ev->data.control.value & 0x7f;
548 }
549
550 /* decode pitch wheel change */
551 static void pitchbend_decode(const snd_seq_event_t *ev, unsigned char *buf)
552 {
553 int value = ev->data.control.value + 8192;
554 buf[0] = value & 0x7f;
555 buf[1] = (value >> 7) & 0x7f;
556 }
557
558 /* decode midi control change */
559 static void two_param_decode(const snd_seq_event_t *ev, unsigned char *buf)
560 {
561 buf[0] = ev->data.control.param & 0x7f;
562 buf[1] = ev->data.control.value & 0x7f;
563 }
564
565 /* decode song position */
566 static void songpos_decode(const snd_seq_event_t *ev, unsigned char *buf)
567 {
568 buf[0] = ev->data.control.value & 0x7f;
569 buf[1] = (ev->data.control.value >> 7) & 0x7f;
570 }
571
572 #ifdef UNNEEDED_BY_DSSI
573 /* decode 14bit control */
574 static int extra_decode_ctrl14(snd_midi_event_t *dev, unsigned char *buf, int count, const snd_seq_event_t *ev)
575 {
576 unsigned char cmd;
577 int idx = 0;
578
579 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f);
580 if (ev->data.control.param < 32) {
581 if (count < 4)
582 return -ENOMEM;
583 if (dev->nostat && count < 6)
584 return -ENOMEM;
585 if (cmd != dev->lastcmd || dev->nostat) {
586 if (count < 5)
587 return -ENOMEM;
588 buf[idx++] = dev->lastcmd = cmd;
589 }
590 buf[idx++] = ev->data.control.param;
591 buf[idx++] = (ev->data.control.value >> 7) & 0x7f;
592 if (dev->nostat)
593 buf[idx++] = cmd;
594 buf[idx++] = ev->data.control.param + 32;
595 buf[idx++] = ev->data.control.value & 0x7f;
596 } else {
597 if (count < 2)
598 return -ENOMEM;
599 if (cmd != dev->lastcmd || dev->nostat) {
600 if (count < 3)
601 return -ENOMEM;
602 buf[idx++] = dev->lastcmd = cmd;
603 }
604 buf[idx++] = ev->data.control.param & 0x7f;
605 buf[idx++] = ev->data.control.value & 0x7f;
606 }
607 return idx;
608 }
609
610 /* decode reg/nonreg param */
611 static int extra_decode_xrpn(snd_midi_event_t *dev, unsigned char *buf, int count, const snd_seq_event_t *ev)
612 {
613 unsigned char cmd;
614 char *cbytes;
615 static char cbytes_nrpn[4] = { MIDI_CTL_NONREG_PARM_NUM_MSB,
616 MIDI_CTL_NONREG_PARM_NUM_LSB,
617 MIDI_CTL_MSB_DATA_ENTRY,
618 MIDI_CTL_LSB_DATA_ENTRY };
619 static char cbytes_rpn[4] = { MIDI_CTL_REGIST_PARM_NUM_MSB,
620 MIDI_CTL_REGIST_PARM_NUM_LSB,
621 MIDI_CTL_MSB_DATA_ENTRY,
622 MIDI_CTL_LSB_DATA_ENTRY };
623 unsigned char bytes[4];
624 int idx = 0, i;
625
626 if (count < 8)
627 return -ENOMEM;
628 if (dev->nostat && count < 12)
629 return -ENOMEM;
630 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f);
631 bytes[0] = ev->data.control.param & 0x007f;
632 bytes[1] = (ev->data.control.param & 0x3f80) >> 7;
633 bytes[2] = ev->data.control.value & 0x007f;
634 bytes[3] = (ev->data.control.value & 0x3f80) >> 7;
635 if (cmd != dev->lastcmd && !dev->nostat) {
636 if (count < 9)
637 return -ENOMEM;
638 buf[idx++] = dev->lastcmd = cmd;
639 }
640 cbytes = ev->type == SND_SEQ_EVENT_NONREGPARAM ? cbytes_nrpn : cbytes_rpn;
641 for (i = 0; i < 4; i++) {
642 if (dev->nostat)
643 buf[idx++] = dev->lastcmd = cmd;
644 buf[idx++] = cbytes[i];
645 buf[idx++] = bytes[i];
646 }
647 return idx;
648 }
649 #endif /* UNNEEDED_BY_DSSI */