xref: /netbsd-src/usr.bin/midiplay/midiplay.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: midiplay.c,v 1.29 2011/11/25 01:39:47 jmcneill Exp $	*/
2 
3 /*
4  * Copyright (c) 1998, 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Lennart Augustsson (augustss@NetBSD.org).
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 #include <sys/cdefs.h>
32 
33 #ifndef lint
34 __RCSID("$NetBSD: midiplay.c,v 1.29 2011/11/25 01:39:47 jmcneill Exp $");
35 #endif
36 
37 
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <fcntl.h>
41 #include <err.h>
42 #include <errno.h>
43 #include <limits.h>
44 #include <unistd.h>
45 #include <string.h>
46 #include <sys/types.h>
47 #include <sys/stat.h>
48 #include <sys/ioctl.h>
49 #include <sys/midiio.h>
50 
51 #define DEVMUSIC "/dev/music"
52 
53 struct track {
54 	struct track *indirect; /* for fast swaps in heap code */
55 	u_char *start, *end;
56 	u_long delta;
57 	u_char status;
58 };
59 
60 #define MIDI_META 0xff
61 
62 #define META_SEQNO	0x00
63 #define META_TEXT	0x01
64 #define META_COPYRIGHT	0x02
65 #define META_TRACK	0x03
66 #define META_INSTRUMENT	0x04
67 #define META_LYRIC	0x05
68 #define META_MARKER	0x06
69 #define META_CUE	0x07
70 #define META_CHPREFIX	0x20
71 #define META_EOT	0x2f
72 #define META_SET_TEMPO	0x51
73 #define META_KEY	0x59
74 #define META_SMPTE	0x54
75 #define META_TIMESIGN	0x58
76 
77 static const char *metanames[] = {
78 	"", "Text", "Copyright", "Track", "Instrument",
79 	"Lyric", "Marker", "Cue",
80 };
81 
82 static int midi_lengths[] = { 2, 2, 2, 2, 1, 1, 2, 0 };
83 /* Number of bytes in a MIDI command */
84 #define MIDI_LENGTH(d) (midi_lengths[((d) >> 4) & 7])
85 
86 #define SEQ_MK_SYSEX0(_dev,...) \
87 SEQ_MK_EVENT(sysex, 0x94, .device=(_dev), .buffer={__VA_ARGS__})
88 
89 
90 static void usage(void);
91 static void send_event(seq_event_t *);
92 static void dometa(u_int, u_char *, u_int);
93 #if 0
94 static void midireset(void);
95 #endif
96 static void send_sysex(u_char *, u_int);
97 static u_long getvar(struct track *);
98 static u_long getlen(struct track *);
99 static void playfile(FILE *, const char *);
100 static void playdata(u_char *, u_int, const char *);
101 
102 static void Heapify(struct track *, int, int);
103 static void BuildHeap(struct track *, int);
104 static int ShrinkHeap(struct track *, int);
105 
106 /*
107  * This sample plays at an apparent tempo of 120 bpm when the BASETEMPO is 150
108  * bpm, because the quavers are 5 divisions (4 on 1 off) rather than 4 total.
109  */
110 #define P(c) 1, 0x90, c, 0x7f, 4, 0x80, c, 0
111 #define PL(c) 1, 0x90, c, 0x7f, 8, 0x80, c, 0
112 #define C 0x3c
113 #define D 0x3e
114 #define E 0x40
115 #define F 0x41
116 
117 static u_char sample[] = {
118 	'M', 'T', 'h', 'd',  0, 0, 0, 6,  0, 1,  0, 1,  0, 8,
119 	'M', 'T', 'r', 'k',  0, 0, 0, 4+13*8,
120 	P(C), P(C), P(C), P(E), P(D), P(D), P(D),
121 	P(F), P(E), P(E), P(D), P(D), PL(C),
122 	0, 0xff, 0x2f, 0
123 };
124 #undef P
125 #undef PL
126 #undef C
127 #undef D
128 #undef E
129 #undef F
130 
131 #define MARK_HEADER "MThd"
132 #define MARK_TRACK "MTrk"
133 #define MARK_LEN 4
134 
135 #define	RMID_SIG "RIFF"
136 #define	RMID_MIDI_ID "RMID"
137 #define	RMID_DATA_ID "data"
138 
139 #define SIZE_LEN 4
140 #define HEADER_LEN 6
141 
142 #define GET8(p) ((p)[0])
143 #define GET16(p) (((p)[0] << 8) | (p)[1])
144 #define GET24(p) (((p)[0] << 16) | ((p)[1] << 8) | (p)[2])
145 #define GET32(p) (((p)[0] << 24) | ((p)[1] << 16) | ((p)[2] << 8) | (p)[3])
146 #define GET32_LE(p) (((p)[3] << 24) | ((p)[2] << 16) | ((p)[1] << 8) | (p)[0])
147 
148 static void __attribute__((__noreturn__))
149 usage(void)
150 {
151 	fprintf(stderr, "usage: %s [-d unit] [-f file] [-l] [-m] [-p pgm] [-q] "
152 	       "[-t %%tempo] [-v] [-x] [file ...]\n",
153 		getprogname());
154 	exit(1);
155 }
156 
157 static int showmeta = 0;
158 static int verbose = 0;
159 #define BASETEMPO 400000		/* us/beat(=24 clks or qn) (150 bpm) */
160 static u_int tempo_set = 0;
161 static u_int tempo_abs = 0;
162 static u_int ttempo = 100;
163 static int unit = 0;
164 static int play = 1;
165 static int fd = -1;
166 static int sameprogram = 0;
167 static int insysex = 0;
168 static int svsysex = 0; /* number of sysex bytes saved internally */
169 
170 static void
171 send_event(seq_event_t *ev)
172 {
173 	/*
174 	printf("%02x %02x %02x %02x %02x %02x %02x %02x\n",
175 	       ev->arr[0], ev->arr[1], ev->arr[2], ev->arr[3],
176 	       ev->arr[4], ev->arr[5], ev->arr[6], ev->arr[7]);
177 	*/
178 	if (play)
179 		write(fd, ev, sizeof *ev);
180 }
181 
182 static u_long
183 getvar(struct track *tp)
184 {
185 	u_long r, c;
186 
187 	r = 0;
188 	do {
189 		c = *tp->start++;
190 		r = (r << 7) | (c & 0x7f);
191 	} while ((c & 0x80) && tp->start < tp->end);
192 	return r;
193 }
194 
195 static u_long
196 getlen(struct track *tp)
197 {
198 	u_long len;
199 	len = getvar(tp);
200 	if (tp->start + len > tp->end)
201 		errx(1, "bogus item length exceeds remaining track size");
202 	return len;
203 }
204 
205 static void
206 dometa(u_int meta, u_char *p, u_int len)
207 {
208 	static char const * const keys[] = {
209 	        "Cb", "Gb", "Db", "Ab", "Eb", "Bb", "F",
210 		"C",
211 		"G", "D", "A", "E", "B", "F#", "C#",
212 		"G#", "D#", "A#" /* for minors */
213 	};
214 	seq_event_t ev;
215 	uint32_t usperbeat;
216 
217 	switch (meta) {
218 	case META_TEXT:
219 	case META_COPYRIGHT:
220 	case META_TRACK:
221 	case META_INSTRUMENT:
222 	case META_LYRIC:
223 	case META_MARKER:
224 	case META_CUE:
225 		if (showmeta) {
226 			printf("%s: ", metanames[meta]);
227 			fwrite(p, len, 1, stdout);
228 			printf("\n");
229 		}
230 		break;
231 	case META_SET_TEMPO:
232 		usperbeat = GET24(p);
233 		ev = SEQ_MK_TIMING(TEMPO,
234 		    .bpm=(60000000. / usperbeat) * (ttempo / 100.) + 0.5);
235 		if (showmeta)
236 			printf("Tempo: %u us/'beat'(24 midiclks)"
237 			       " at %u%%; adjusted bpm = %u\n",
238 			       usperbeat, ttempo, ev.t_TEMPO.bpm);
239 		if (tempo_abs)
240 			warnx("tempo event ignored"
241 			      " in absolute-timed MIDI file");
242 		else {
243 			send_event(&ev);
244 			if (!tempo_set) {
245 				tempo_set = 1;
246 				send_event(&SEQ_MK_TIMING(START));
247 			}
248 		}
249 		break;
250 	case META_TIMESIGN:
251 		ev = SEQ_MK_TIMING(TIMESIG,
252 		    .numerator=p[0],      .lg2denom=p[1],
253 		    .clks_per_click=p[2], .dsq_per_24clks=p[3]);
254 		if (showmeta) {
255 			printf("Time signature: %d/%d."
256 			       " Click every %d midiclk%s"
257 			       " (24 midiclks = %d 32nd note%s)\n",
258 			       ev.t_TIMESIG.numerator,
259 			       1 << ev.t_TIMESIG.lg2denom,
260 			       ev.t_TIMESIG.clks_per_click,
261 			       1 == ev.t_TIMESIG.clks_per_click ? "" : "s",
262 			       ev.t_TIMESIG.dsq_per_24clks,
263 			       1 == ev.t_TIMESIG.dsq_per_24clks ? "" : "s");
264 		}
265 		/* send_event(&ev); not implemented in sequencer */
266 		break;
267 	case META_KEY:
268 		if (showmeta)
269 			printf("Key: %s %s\n",
270 			       keys[((char)p[0]) + p[1] ? 10 : 7],
271 			       p[1] ? "minor" : "major");
272 		break;
273 	default:
274 		break;
275 	}
276 }
277 
278 #if 0
279 static void
280 midireset(void)
281 {
282 	/* General MIDI reset sequence */
283 	send_event(&SEQ_MK_SYSEX0(unit, 0x7e, 0x7f, 0x09, 0x01, 0xf7, 0xff));
284 }
285 #endif
286 
287 #define SYSEX_CHUNK 6
288 static void
289 send_sysex(u_char *p, u_int l)
290 {
291 	seq_event_t event;
292 	static u_char bf[6];
293 
294 	if (0 == l) {
295 		warnx("zero-length system-exclusive event");
296 		return;
297 	}
298 
299 	/*
300 	 * This block is needed only to handle the possibility that a sysex
301 	 * message is broken into multiple events in a MIDI file that do not
302 	 * have length six; the /dev/music sequencer assumes a sysex message is
303 	 * finished with the first SYSEX event carrying fewer than six bytes,
304 	 * even if the last is not MIDI_SYSEX_END. So, we need to be careful
305 	 * not to send a short sysex event until we have seen the end byte.
306 	 * Instead, save some straggling bytes in bf, and send when we have a
307 	 * full six (or an end byte). Note bf/saved/insysex should be per-
308 	 * device, if we supported output to more than one device at a time.
309 	 */
310 	if (svsysex > 0) {
311 		if (l > sizeof bf - svsysex) {
312 			memcpy(bf + svsysex, p, sizeof bf - svsysex);
313 			l -= sizeof bf - svsysex;
314 			p += sizeof bf - svsysex;
315 			send_event(&SEQ_MK_SYSEX0(unit,
316 			    bf[0], bf[1], bf[2], bf[3], bf[4], bf[5]));
317 			svsysex = 0;
318 		} else {
319 			memcpy(bf + svsysex, p, l);
320 			svsysex += l;
321 			p += l;
322 			if (MIDI_SYSEX_END == bf[svsysex-1]) {
323 				event = SEQ_MK_SYSEX(unit);
324 				memcpy(event.sysex.buffer, bf, svsysex);
325 				send_event(&event);
326 				svsysex = insysex = 0;
327 			} else
328 				insysex = 1;
329 			return;
330 		}
331 	}
332 
333 	/*
334 	 * l > 0. May as well test now whether we will be left 'insysex'
335 	 * after processing this event.
336 	 */
337 	insysex = (MIDI_SYSEX_END != p[l-1]);
338 
339 	/*
340 	 * If not for multi-event sysexes and chunk-size weirdness, this
341 	 * function could pretty much start here. :)
342 	 */
343 	while (l >= SYSEX_CHUNK) {
344 		send_event(&SEQ_MK_SYSEX0(unit, p[0], p[1], p[2], p[3], p[4], p[5]));
345 		p += SYSEX_CHUNK;
346 		l -= SYSEX_CHUNK;
347 	}
348 	if (l > 0) {
349 		if (insysex) {
350 			memcpy(bf, p, l);
351 			svsysex = l;
352 		} else { /* a <6 byte chunk is ok if it's REALLY the end */
353 			event = SEQ_MK_SYSEX(unit);
354 			memcpy(event.sysex.buffer, p, l);
355 			send_event(&event);
356 		}
357 	}
358 }
359 
360 static void
361 playfile(FILE *f, const char *name)
362 {
363 	u_char *buf, *nbuf;
364 	u_int tot, n, size, nread;
365 
366 	/*
367 	 * We need to read the whole file into memory for easy processing.
368 	 * Using mmap() would be nice, but some file systems do not support
369 	 * it, nor does reading from e.g. a pipe.  The latter also precludes
370 	 * finding out the file size without reading it.
371 	 */
372 	size = 1000;
373 	buf = malloc(size);
374 	if (buf == 0)
375 		errx(1, "malloc() failed");
376 	nread = size;
377 	tot = 0;
378 	for (;;) {
379 		n = fread(buf + tot, 1, nread, f);
380 		tot += n;
381 		if (n < nread)
382 			break;
383 		/* There must be more to read. */
384 		nread = size;
385 		nbuf = realloc(buf, size * 2);
386 		if (nbuf == NULL)
387 			errx(1, "realloc() failed");
388 		buf = nbuf;
389 		size *= 2;
390 	}
391 	playdata(buf, tot, name);
392 	free(buf);
393 }
394 
395 static void
396 playdata(u_char *buf, u_int tot, const char *name)
397 {
398 	int format, ntrks, divfmt, ticks, t;
399 	u_int len, mlen, status, chan;
400 	u_char *p, *end, byte, meta, *msg;
401 	struct synth_info info;
402 	struct track *tracks;
403 	struct track *tp;
404 
405 	/* verify that the requested midi unit exists */
406 	info.device = unit;
407 	if (ioctl(fd, SEQUENCER_INFO, &info) < 0)
408 		err(1, "ioctl(SEQUENCER_INFO) failed");
409 
410 	end = buf + tot;
411 	if (verbose)
412 		printf("Playing %s (%d bytes) on %s (unit %d)... \n",
413 		    name, tot, info.name, info.device);
414 
415 	if (tot < MARK_LEN + 4) {
416 		warnx("Not a MIDI file, too short");
417 		return;
418 	}
419 
420 	if (memcmp(buf, RMID_SIG, MARK_LEN) == 0) {
421 		u_char *eod;
422 		/* Detected a RMID file, let's just check if it's
423 		 * a MIDI file */
424 		if ((u_int)GET32_LE(buf + MARK_LEN) != tot - 8) {
425 			warnx("Not a RMID file, bad header");
426 			return;
427 		}
428 
429 		buf += MARK_LEN + 4;
430 		if (memcmp(buf, RMID_MIDI_ID, MARK_LEN) != 0) {
431 			warnx("Not a RMID file, bad ID");
432 			return;
433 		}
434 
435 		/* Now look for the 'data' chunk, which contains
436 		 * MIDI data */
437 		buf += MARK_LEN;
438 
439 		/* Test against end-8 since we must have at least 8 bytes
440 		 * left to read */
441 		while(buf < end-8 && memcmp(buf, RMID_DATA_ID, MARK_LEN))
442 			buf += GET32_LE(buf+4) + 8; /* MARK_LEN + 4 */
443 
444 		if (buf >= end-8) {
445 			warnx("Not a valid RMID file, no data chunk");
446 			return;
447 		}
448 
449 		buf += MARK_LEN; /* "data" */
450 		eod = buf + 4 + GET32_LE(buf);
451 		if (eod >= end) {
452 			warnx("Not a valid RMID file, bad data chunk size");
453 			return;
454 		}
455 
456 		end = eod;
457 		buf += 4;
458 	}
459 
460 	if (memcmp(buf, MARK_HEADER, MARK_LEN) != 0) {
461 		warnx("Not a MIDI file, missing header");
462 		return;
463 	}
464 
465 	if (GET32(buf + MARK_LEN) != HEADER_LEN) {
466 		warnx("Not a MIDI file, bad header");
467 		return;
468 	}
469 	format = GET16(buf + MARK_LEN + SIZE_LEN);
470 	ntrks = GET16(buf + MARK_LEN + SIZE_LEN + 2);
471 	divfmt = GET8(buf + MARK_LEN + SIZE_LEN + 4);
472 	ticks = GET8(buf + MARK_LEN + SIZE_LEN + 5);
473 	p = buf + MARK_LEN + SIZE_LEN + HEADER_LEN;
474 	/*
475 	 * Set the timebase (or timebase and tempo, for absolute-timed files).
476 	 * PORTABILITY: some sequencers actually check the timebase against
477 	 * available timing sources and may adjust it accordingly (storing a
478 	 * new value in the ioctl arg) which would require us to compensate
479 	 * somehow. That possibility is ignored for now, as NetBSD's sequencer
480 	 * currently synthesizes all timebases, for better or worse, from the
481 	 * system clock.
482 	 *
483 	 * For a non-absolute file, if timebase is set to the file's divisions
484 	 * value, and tempo set in the obvious way, then the timing deltas in
485 	 * the MTrks require no scaling. A downside to this approach is that
486 	 * the sequencer API wants tempo in (integer) beats per minute, which
487 	 * limits how finely tempo can be specified. That might be got around
488 	 * in some cases by frobbing tempo and timebase more obscurely, but this
489 	 * player is meant to be simple and clear.
490 	 */
491 	if ((divfmt & 0x80) == 0) {
492 		ticks |= divfmt << 8;
493 		if (ioctl(fd, SEQUENCER_TMR_TIMEBASE, &(int){ticks}) < 0)
494 			err(1, "SEQUENCER_TMR_TIMEBASE");
495 	} else {
496 		tempo_abs = tempo_set = 1;
497 		divfmt = -(int8_t)divfmt;
498 		/*
499 		 * divfmt is frames per second; multiplying by 60 to set tempo
500 		 * in frames per minute could exceed sequencer's (arbitrary)
501 		 * tempo limits, so factor 60 as 12*5, set tempo in frames per
502 		 * 12 seconds, and account for the 5 in timebase.
503 		 */
504 		send_event(&SEQ_MK_TIMING(TEMPO,
505 		    .bpm=(12*divfmt) * (ttempo/100.) + 0.5));
506 		if (ioctl(fd, SEQUENCER_TMR_TIMEBASE, &(int){5*ticks}) < 0)
507 			err(1, "SEQUENCER_TMR_TIMEBASE");
508 	}
509 	if (verbose > 1)
510 		printf(tempo_abs ?
511 		       "format=%d ntrks=%d abs fps=%u subdivs=%u\n" :
512 		       "format=%d ntrks=%d divisions=%u\n",
513 		       format, ntrks, tempo_abs ? divfmt : ticks, ticks);
514 	if (format != 0 && format != 1) {
515 		warnx("Cannot play MIDI file of type %d", format);
516 		return;
517 	}
518 	if (ntrks == 0)
519 		return;
520 	tracks = malloc(ntrks * sizeof(struct track));
521 	if (tracks == NULL)
522 		errx(1, "malloc() tracks failed");
523 	for (t = 0; t < ntrks;) {
524 		if (p >= end - MARK_LEN - SIZE_LEN) {
525 			warnx("Cannot find track %d", t);
526 			goto ret;
527 		}
528 		len = GET32(p + MARK_LEN);
529 		if (len > 1000000) { /* a safe guard */
530 			warnx("Crazy track length");
531 			goto ret;
532 		}
533 		if (memcmp(p, MARK_TRACK, MARK_LEN) == 0) {
534 			tracks[t].start = p + MARK_LEN + SIZE_LEN;
535 			tracks[t].end = tracks[t].start + len;
536 			tracks[t].delta = getvar(&tracks[t]);
537 			tracks[t].indirect = &tracks[t]; /* -> self for now */
538 			t++;
539 		}
540 		p += MARK_LEN + SIZE_LEN + len;
541 	}
542 
543 	/*
544 	 * Force every channel to the same patch if requested by the user.
545 	 */
546 	if (sameprogram) {
547 		for(t = 0; t < 16; t++) {
548 			send_event(&SEQ_MK_CHN(PGM_CHANGE, .device=unit,
549 			    .channel=t, .program=sameprogram-1));
550 		}
551 	}
552 	/*
553 	 * Play MIDI events by selecting the track with the lowest
554 	 * delta.  Execute the event, update the delta and repeat.
555 	 *
556 	 * The ticks variable is the number of ticks that make up a beat
557 	 * (beat: 24 MIDI clocks always, a quarter note by usual convention)
558 	 * and is used as a reference value for the delays between
559 	 * the MIDI events.
560 	 */
561 	BuildHeap(tracks, ntrks); /* tracks[0].indirect is always next */
562 	for (;;) {
563 		tp = tracks[0].indirect;
564 		if ((verbose > 2 && tp->delta > 0)  ||  verbose > 3) {
565 			printf("DELAY %4ld TRACK %2td%s",
566 			       tp->delta, tp - tracks, verbose>3?" ":"\n");
567 			fflush(stdout);
568 		}
569 		if (tp->delta > 0) {
570 			if (!tempo_set) {
571 				if (verbose || showmeta)
572 					printf("No initial tempo;"
573 					       " defaulting:\n");
574 				dometa(META_SET_TEMPO, (u_char[]){
575 				    BASETEMPO >> 16,
576 				    (BASETEMPO >> 8) & 0xff,
577 				    BASETEMPO & 0xff},
578 				    3);
579 			}
580 			send_event(&SEQ_MK_TIMING(WAIT_REL,
581 			    .divisions=tp->delta));
582 		}
583 		byte = *tp->start++;
584 		if (byte == MIDI_META) {
585 			meta = *tp->start++;
586 			mlen = getlen(tp);
587 			if (verbose > 3)
588 				printf("META %02x (%d)\n", meta, mlen);
589 			dometa(meta, tp->start, mlen);
590 			tp->start += mlen;
591 		} else {
592 			if (MIDI_IS_STATUS(byte))
593 				tp->status = byte;
594 			else
595 				tp->start--;
596 			mlen = MIDI_LENGTH(tp->status);
597 			msg = tp->start;
598 			if (verbose > 3) {
599 			    if (mlen == 1)
600 				printf("MIDI %02x (%d) %02x\n",
601 				       tp->status, mlen, msg[0]);
602 			    else
603 				printf("MIDI %02x (%d) %02x %02x\n",
604 				       tp->status, mlen, msg[0], msg[1]);
605 			}
606 			if (insysex && tp->status != MIDI_SYSEX_END) {
607 				warnx("incomplete system exclusive message"
608 				      " aborted");
609 				svsysex = insysex = 0;
610 			}
611 			status = MIDI_GET_STATUS(tp->status);
612 			chan = MIDI_GET_CHAN(tp->status);
613 			switch (status) {
614 			case MIDI_NOTEOFF:
615 				send_event(&SEQ_MK_CHN(NOTEOFF, .device=unit,
616 				.channel=chan, .key=msg[0], .velocity=msg[1]));
617 				break;
618 			case MIDI_NOTEON:
619 				send_event(&SEQ_MK_CHN(NOTEON, .device=unit,
620 				.channel=chan, .key=msg[0], .velocity=msg[1]));
621 				break;
622 			case MIDI_KEY_PRESSURE:
623 				send_event(&SEQ_MK_CHN(KEY_PRESSURE,
624 				.device=unit, .channel=chan,
625 				.key=msg[0], .pressure=msg[1]));
626 				break;
627 			case MIDI_CTL_CHANGE:
628 				send_event(&SEQ_MK_CHN(CTL_CHANGE,
629 				.device=unit, .channel=chan,
630 				.controller=msg[0], .value=msg[1]));
631 				break;
632 			case MIDI_PGM_CHANGE:
633 				if (!sameprogram)
634 					send_event(&SEQ_MK_CHN(PGM_CHANGE,
635 					.device=unit, .channel=chan,
636 					.program=msg[0]));
637 				break;
638 			case MIDI_CHN_PRESSURE:
639 				send_event(&SEQ_MK_CHN(CHN_PRESSURE,
640 				.device=unit, .channel=chan, .pressure=msg[0]));
641 				break;
642 			case MIDI_PITCH_BEND:
643 				send_event(&SEQ_MK_CHN(PITCH_BEND,
644 				.device=unit, .channel=chan,
645 				.value=(msg[0] & 0x7f) | ((msg[1] & 0x7f)<<7)));
646 				break;
647 			case MIDI_SYSTEM_PREFIX:
648 				mlen = getlen(tp);
649 				if (tp->status == MIDI_SYSEX_START) {
650 					send_sysex(tp->start, mlen);
651 					break;
652 				} else if (tp->status == MIDI_SYSEX_END) {
653 				/* SMF uses SYSEX_END as CONTINUATION/ESCAPE */
654 					if (insysex) { /* CONTINUATION */
655 						send_sysex(tp->start, mlen);
656 					} else { /* ESCAPE */
657 						for (; mlen > 0 ; -- mlen) {
658 							send_event(
659 							    &SEQ_MK_EVENT(putc,
660 							    SEQOLD_MIDIPUTC,
661 							    .device=unit,
662 							    .byte=*(tp->start++)
663 							   ));
664 						}
665 					}
666 					break;
667 				}
668 				/* Sorry, can't do this yet; FALLTHROUGH */
669 			default:
670 				if (verbose)
671 					printf("MIDI event 0x%02x ignored\n",
672 					       tp->status);
673 			}
674 			tp->start += mlen;
675 		}
676 		if (tp->start >= tp->end) {
677 			ntrks = ShrinkHeap(tracks, ntrks); /* track gone */
678 			if (0 == ntrks)
679 				break;
680 		} else
681 			tp->delta = getvar(tp);
682 		Heapify(tracks, ntrks, 0);
683 	}
684 	if (ioctl(fd, SEQUENCER_SYNC, 0) < 0)
685 		err(1, "SEQUENCER_SYNC");
686 
687  ret:
688 	free(tracks);
689 }
690 
691 static int
692 parse_unit(const char *sunit)
693 {
694 	const char *osunit = sunit;
695 	long n;
696 	char *ep;
697 
698 	if (strncmp(sunit, "midi", strlen("midi")) == 0)
699 		sunit += strlen("midi");
700 
701 	errno = 0;
702 	n = strtol(sunit, &ep, 10);
703 	if (n < 0 || n > INT_MAX || *ep != '\0' ||
704 	    (errno == ERANGE &&
705 	    (n == LONG_MAX || n == LONG_MIN)))
706 		errx(1, "bad midi unit -- %s", osunit);
707 
708 	return (int)n;
709 }
710 
711 int
712 main(int argc, char **argv)
713 {
714 	int ch;
715 	int listdevs = 0;
716 	int example = 0;
717 	int nmidi;
718 	const char *file = DEVMUSIC;
719 	const char *sunit;
720 	struct synth_info info;
721 	FILE *f;
722 
723 	if ((sunit = getenv("MIDIUNIT")))
724 		unit = parse_unit(sunit);
725 
726 	while ((ch = getopt(argc, argv, "?d:f:lmp:qt:vx")) != -1) {
727 		switch(ch) {
728 		case 'd':
729 			unit = parse_unit(optarg);
730 			break;
731 		case 'f':
732 			file = optarg;
733 			break;
734 		case 'l':
735 			listdevs++;
736 			break;
737 		case 'm':
738 			showmeta++;
739 			break;
740 		case 'p':
741 			sameprogram = atoi(optarg);
742 			break;
743 		case 'q':
744 			play = 0;
745 			break;
746 		case 't':
747 			ttempo = atoi(optarg);
748 			break;
749 		case 'v':
750 			verbose++;
751 			break;
752 		case 'x':
753 			example++;
754 			break;
755 		case '?':
756 		default:
757 			usage();
758 		}
759 	}
760 	argc -= optind;
761 	argv += optind;
762 
763 	if (!play)
764 		goto output;
765 
766 	fd = open(file, O_WRONLY);
767 	if (fd < 0)
768 		err(1, "%s", file);
769 	if (ioctl(fd, SEQUENCER_NRMIDIS, &nmidi) < 0)
770 		err(1, "ioctl(SEQUENCER_NRMIDIS) failed, ");
771 	if (nmidi == 0)
772 		errx(1, "Sorry, no MIDI devices available");
773 	if (listdevs) {
774 		for (info.device = 0; info.device < nmidi; info.device++) {
775 			if (ioctl(fd, SEQUENCER_INFO, &info) < 0)
776 				err(1, "ioctl(SEQUENCER_INFO) failed, ");
777 			printf("%d: %s\n", info.device, info.name);
778 		}
779 		exit(0);
780 	}
781 
782  output:
783 	if (example)
784 		while (example--)
785 			playdata(sample, sizeof sample, "<Gubben Noa>");
786 	else if (argc == 0)
787 		playfile(stdin, "<stdin>");
788 	else
789 		while (argc--) {
790 			f = fopen(*argv, "r");
791 			if (f == NULL)
792 				err(1, "%s", *argv);
793 			else {
794 				playfile(f, *argv);
795 				fclose(f);
796 			}
797 			argv++;
798 		}
799 
800 	exit(0);
801 }
802 
803 /*
804  * relative-time priority queue (min-heap). Properties:
805  * 1. The delta time at a node is relative to the node's parent's time.
806  * 2. When an event is dequeued from a track, the delta time of the new head
807  *    event is relative to the time of the event just dequeued.
808  * Therefore:
809  * 3. After dequeueing the head event from the track at heap root, the next
810  *    event's time is directly comparable to the root's children.
811  * These properties allow the heap to be maintained with delta times throughout.
812  * Insert is also implementable, but not needed: all the tracks are present
813  * at first; they just go away as they end.
814  */
815 
816 #define PARENT(i) ((i - 1) >> 1)
817 #define LEFT(i)   ((i << 1) + 1)
818 #define RIGHT(i)  ((i + 1) << 1)
819 #define DTIME(i)  (t[i].indirect->delta)
820 #define SWAP(i, j) do { \
821     struct track *_t = t[i].indirect; \
822     t[i].indirect = t[j].indirect; \
823     t[j].indirect = _t; \
824 } while (/*CONSTCOND*/ 0)
825 
826 static void
827 Heapify(struct track *t, int ntrks, int node)
828 {
829 	int lc, rc, mn;
830 
831 	lc = LEFT(node);
832 	rc = RIGHT(node);
833 
834 	if (rc >= ntrks) {			/* no right child */
835 		if (lc >= ntrks)		/* node is a leaf */
836 			return;
837 		if (DTIME(node) > DTIME(lc))
838 			SWAP(node, lc);
839 		DTIME(lc) -= DTIME(node);
840 		return;				/* no rc ==> lc is a leaf */
841 	}
842 
843 	mn = lc;
844 	if (DTIME(lc) > DTIME(rc))
845 		mn = rc;
846 	if (DTIME(node) <= DTIME(mn)) {
847 		DTIME(rc) -= DTIME(node);
848 		DTIME(lc) -= DTIME(node);
849 		return;
850 	}
851 
852 	SWAP(node, mn);
853 	DTIME(rc) -= DTIME(node);
854 	DTIME(lc) -= DTIME(node);
855 	Heapify(t, ntrks, mn); /* gcc groks tail recursion */
856 }
857 
858 static void
859 BuildHeap(struct track *t, int ntrks)
860 {
861 	int node;
862 
863 	for (node = PARENT(ntrks - 1); node --> 0;)
864 		Heapify(t, ntrks, node);
865 }
866 
867 /*
868  * Make the heap 1 item smaller by discarding the track at the root. Move the
869  * rightmost bottom-level leaf to the root and decrement ntrks. It remains to
870  * run Heapify, which the caller is expected to do. Returns the new ntrks.
871  */
872 static int
873 ShrinkHeap(struct track *t, int ntrks)
874 {
875 	int ancest;
876 
877 	--ntrks;
878 	for (ancest = PARENT(ntrks); ancest > 0; ancest = PARENT(ancest))
879 		DTIME(ntrks) += DTIME(ancest);
880 	t[0].indirect = t[ntrks].indirect;
881 	return ntrks;
882 }
883