src/sound.c

   1 /* sound.c -- sound support.
   2    Copyright (C) 1998 Free Software Foundation.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 /* Written by Gerd Moellmann <gerd@gnu.org>.  Tested with Luigi's
  22    driver on FreeBSD 2.2.7 with a SoundBlaster 16.  */
  23
  24 #include <config.h>
  25
  26 #if defined HAVE_SOUND
  27
  28 #include <lisp.h>
  29 #include <fcntl.h>
  30 #include <unistd.h>
  31 #include <sys/types.h>
  32 #include <dispextern.h>
  33 #include <errno.h>
  34
  35 /* FreeBSD has machine/soundcard.h.  Voxware sound driver docs mention
  36    sys/soundcard.h.  So, let's try whatever's there.  */
  37
  38 #ifdef HAVE_MACHINE_SOUNDCARD_H
  39 #include <machine/soundcard.h>
  40 #endif
  41 #ifdef HAVE_SYS_SOUNDCARD_H
  42 #include <sys/soundcard.h>
  43 #endif
  44
  45 #define max(X, Y) ((X) > (Y) ? (X) : (Y))
  46 #define min(X, Y) ((X) < (Y) ? (X) : (Y))
  47 #define abs(X)    ((X) < 0 ? -(X) : (X))
  48
  49 /* Structure forward declarations.  */
  50
  51 struct sound_file;
  52 struct sound_device;
  53
  54 /* The file header of RIFF-WAVE files (*.wav).  Files are always in
  55    little-endian byte-order.  */
  56
  57 struct wav_header
  58 {
  59   u_int32_t magic;
  60   u_int32_t length;
  61   u_int32_t chunk_type;
  62   u_int32_t chunk_format;
  63   u_int32_t chunk_length;
  64   u_int16_t format;
  65   u_int16_t channels;
  66   u_int32_t sample_rate;
  67   u_int32_t bytes_per_second;
  68   u_int16_t sample_size;
  69   u_int16_t precision;
  70   u_int32_t chunk_data;
  71   u_int32_t data_length;
  72 };
  73
  74 /* The file header of Sun adio files (*.au).  Files are always in
  75    big-endian byte-order.  */
  76
  77 struct au_header
  78 {
  79   /* ASCII ".snd" */
  80   u_int32_t magic_number;
  81
  82   /* Offset of data part from start of file. Minimum value is 24.  */
  83   u_int32_t data_offset;
  84
  85   /* Size of data part, 0xffffffff if unknown.  */
  86   u_int32_t data_size;
  87
  88   /* Data encoding format.
  89      1  8-bit ISDN u-law
  90      2  8-bit linear PCM (REF-PCM)
  91      3  16-bit linear PCM
  92      4  24-bit linear PCM
  93      5  32-bit linear PCM
  94      6  32-bit IEEE floating-point
  95      7  64-bit IEEE floating-point
  96      23 8-bit u-law compressed using CCITT 0.721 ADPCM voice data
  97      encoding scheme.  */
  98   u_int32_t encoding;
  99
 100   /* Number of samples per second.  */
 101   u_int32_t sample_rate;
 102
 103   /* Number of interleaved channels.  */
 104   u_int32_t channels;
 105 };
 106
 107 /* Maximum of all sound file headers sizes.  */
 108
 109 #define MAX_SOUND_HEADER_BYTES \
 110      max (sizeof (struct wav_header), sizeof (struct au_header))
 111
 112 /* Interface structure for sound devices.  */
 113
 114 struct sound_device
 115 {
 116   /* The name of the device or null meaning use a default device name.  */
 117   char *file;
 118
 119   /* File descriptor of the device.  */
 120   int fd;
 121
 122   /* Device-dependent format.  */
 123   int format;
 124
 125   /* Volume (0..100).  Zero means unspecified.  */
 126   int volume;
 127
 128   /* Sample size.  */
 129   int sample_size;
 130
 131   /* Sample rate.  */
 132   int sample_rate;
 133
 134   /* Bytes per second.  */
 135   int bps;
 136
 137   /* 1 = mono, 2 = stereo, 0 = don't set.  */
 138   int channels;
 139
 140   /* Open device SD.  */
 141   void (* open) P_ ((struct sound_device *sd));
 142
 143   /* Close device SD.  */
 144   void (* close) P_ ((struct sound_device *sd));
 145
 146   /* Configure SD accoring to device-dependent parameters.  */
 147   void (* configure) P_ ((struct sound_device *device));
 148
 149   /* Choose a device-dependent format for outputting sound file SF.  */
 150   void (* choose_format) P_ ((struct sound_device *sd,
 151                               struct sound_file *sf));
 152
 153   /* Write NYBTES bytes from BUFFER to device SD.  */
 154   void (* write) P_ ((struct sound_device *sd, char *buffer, int nbytes));
 155
 156   /* A place for devices to store additional data.  */
 157   void *data;
 158 };
 159
 160 /* An enumerator for each supported sound file type.  */
 161
 162 enum sound_type
 163 {
 164   RIFF,
 165   SUN_AUDIO
 166 };
 167
 168 /* Interface structure for sound files.  */
 169
 170 struct sound_file
 171 {
 172   /* The type of the file.  */
 173   enum sound_type type;
 174
 175   /* File descriptor of the file.  */
 176   int fd;
 177
 178   /* Pointer to sound file header.  This contains the first
 179      MAX_SOUND_HEADER_BYTES read from the file.  */
 180   char *header;
 181
 182   /* Play sound file SF on device SD.  */
 183   void (* play) P_ ((struct sound_file *sf, struct sound_device *sd));
 184 };
 185
 186 /* Indices of attributes in a sound attributes vector.  */
 187
 188 enum sound_attr
 189 {
 190   SOUND_FILE,
 191   SOUND_DEVICE,
 192   SOUND_VOLUME,
 193   SOUND_ATTR_SENTINEL
 194 };
 195
 196 /* Symbols.  */
 197
 198 extern Lisp_Object QCfile;
 199 Lisp_Object QCvolume, QCdevice;
 200 Lisp_Object Qsound;
 201 Lisp_Object Qplay_sound_functions;
 202
 203 /* These are set during `play-sound' so that sound_cleanup has
 204    access to them.  */
 205
 206 struct sound_device *sound_device;
 207 struct sound_file *sound_file;
 208
 209 /* Function prototypes.  */
 210
 211 static void vox_open P_ ((struct sound_device *));
 212 static void vox_configure P_ ((struct sound_device *));
 213 static void vox_close P_ ((struct sound_device *sd));
 214 static void vox_choose_format P_ ((struct sound_device *, struct sound_file *));
 215 static void vox_init P_ ((struct sound_device *));
 216 static void vox_write P_ ((struct sound_device *, char *, int));
 217 static void sound_perror P_ ((char *));
 218 static int parse_sound P_ ((Lisp_Object, Lisp_Object *));
 219 static void find_sound_file_type P_ ((struct sound_file *));
 220 static u_int32_t le2hl P_ ((u_int32_t));
 221 static u_int16_t le2hs P_ ((u_int16_t));
 222 static u_int32_t be2hl P_ ((u_int32_t));
 223 static u_int16_t be2hs P_ ((u_int16_t));
 224 static int wav_init P_ ((struct sound_file *));
 225 static void wav_play P_ ((struct sound_file *, struct sound_device *));
 226 static int au_init P_ ((struct sound_file *));
 227 static void au_play P_ ((struct sound_file *, struct sound_device *));
 228
 229
 230 \f
 231 /***********************************************************************
 232                                General
 233  ***********************************************************************/
 234
 235 /* Like perror, but signals an error.  */
 236
 237 static void
 238 sound_perror (msg)
 239      char *msg;
 240 {
 241   error ("%s: %s", msg, strerror (errno));
 242 }
 243
 244
 245 /* Parse sound specification SOUND, and fill ATTRS with what is
 246    found.  Value is non-zero if SOUND Is a valid sound specification.
 247    A valid sound specification is a list starting with the symbol
 248    `sound'.  The rest of the list is a property list which may
 249    contain the following key/value pairs:
 250
 251    - `:file FILE'
 252
 253    FILE is the sound file to play.  If it isn't an absolute name,
 254    it's searched under `data-directory'.
 255
 256    - `:device DEVICE'
 257
 258    DEVICE is the name of the device to play on, e.g. "/dev/dsp2".
 259    If not specified, a default device is used.
 260
 261    - `:volume VOL'
 262
 263    VOL must be an integer in the range [0, 100], or a float in the
 264    range [0, 1].  */
 265
 266 static int
 267 parse_sound (sound, attrs)
 268      Lisp_Object sound;
 269      Lisp_Object *attrs;
 270 {
 271   /* SOUND must be a list starting with the symbol `sound'.  */
 272   if (!CONSP (sound) || !EQ (XCAR (sound), Qsound))
 273     return 0;
 274
 275   sound = XCDR (sound);
 276   attrs[SOUND_FILE] = Fplist_get (sound, QCfile);
 277   attrs[SOUND_DEVICE] = Fplist_get (sound, QCdevice);
 278   attrs[SOUND_VOLUME] = Fplist_get (sound, QCvolume);
 279
 280   /* File name must be specified.  */
 281   if (!STRINGP (attrs[SOUND_FILE]))
 282     return 0;
 283
 284   /* Volume must be in the range 0..100 or unspecified.  */
 285   if (!NILP (attrs[SOUND_VOLUME]))
 286     {
 287       if (INTEGERP (attrs[SOUND_VOLUME]))
 288         {
 289           if (XINT (attrs[SOUND_VOLUME]) < 0
 290               || XINT (attrs[SOUND_VOLUME]) > 100)
 291             return 0;
 292         }
 293       else if (FLOATP (attrs[SOUND_VOLUME]))
 294         {
 295           if (XFLOAT_DATA (attrs[SOUND_VOLUME]) < 0
 296               || XFLOAT_DATA (attrs[SOUND_VOLUME]) > 1)
 297             return 0;
 298         }
 299       else
 300         return 0;
 301     }
 302
 303   /* Device must be a string or unspecified.  */
 304   if (!NILP (attrs[SOUND_DEVICE])
 305       && !STRINGP (attrs[SOUND_DEVICE]))
 306     return 0;
 307
 308   return 1;
 309 }
 310
 311
 312 /* Find out the type of the sound file whose file descriptor is FD.
 313    SF is the sound file structure to fill in.  */
 314
 315 static void
 316 find_sound_file_type (sf)
 317      struct sound_file *sf;
 318 {
 319   if (!wav_init (sf)
 320       && !au_init (sf))
 321     error ("Unknown sound file format");
 322 }
 323
 324
 325 /* Function installed by play-sound with record_unwind_protect.  */
 326
 327 static Lisp_Object
 328 sound_cleanup (arg)
 329      Lisp_Object arg;
 330 {
 331   if (sound_device)
 332     {
 333       sound_device->close (sound_device);
 334       if (sound_file->fd > 0)
 335         close (sound_file->fd);
 336     }
 337 }
 338
 339
 340 DEFUN ("play-sound", Fplay_sound, Splay_sound, 1, 1, 0,
 341   "Play sound SOUND.")
 342   (sound)
 343      Lisp_Object sound;
 344 {
 345   Lisp_Object attrs[SOUND_ATTR_SENTINEL];
 346   char *header;
 347   Lisp_Object file;
 348   struct gcpro gcpro1, gcpro2;
 349   int nbytes;
 350   char *msg;
 351   struct sound_device sd;
 352   struct sound_file sf;
 353   Lisp_Object args[2];
 354   int count = specpdl_ptr - specpdl;
 355
 356   file = Qnil;
 357   GCPRO2 (sound, file);
 358   bzero (&sd, sizeof sd);
 359   bzero (&sf, sizeof sf);
 360   sf.header = (char *) alloca (MAX_SOUND_HEADER_BYTES);
 361
 362   sound_device = &sd;
 363   sound_file = &sf;
 364   record_unwind_protect (sound_cleanup, Qnil);
 365
 366   /* Parse the sound specification.  Give up if it is invalid.  */
 367   if (!parse_sound (sound, attrs))
 368     {
 369       UNGCPRO;
 370       error ("Invalid sound specification");
 371     }
 372
 373   /* Open the sound file.  */
 374   sf.fd = openp (Fcons (Vdata_directory, Qnil),
 375                  attrs[SOUND_FILE], "", &file, 0);
 376   if (sf.fd < 0)
 377     sound_perror ("Open sound file");
 378
 379   /* Read the first bytes from the file.  */
 380   nbytes = read (sf.fd, sf.header, MAX_SOUND_HEADER_BYTES);
 381   if (nbytes < 0)
 382     sound_perror ("Reading sound file header");
 383
 384   /* Find out the type of sound file.  Give up if we can't tell.  */
 385   find_sound_file_type (&sf);
 386
 387   /* Set up a device.  */
 388   if (STRINGP (attrs[SOUND_DEVICE]))
 389     {
 390       int len = XSTRING (attrs[SOUND_DEVICE])->size;
 391       sd.file = (char *) alloca (len + 1);
 392       strcpy (sd.file, XSTRING (attrs[SOUND_DEVICE])->data);
 393     }
 394   if (INTEGERP (attrs[SOUND_VOLUME]))
 395     sd.volume = XFASTINT (attrs[SOUND_VOLUME]);
 396   else if (FLOATP (attrs[SOUND_VOLUME]))
 397     sd.volume = XFLOAT_DATA (attrs[SOUND_VOLUME]) * 100;
 398
 399   args[0] = Qplay_sound_functions;
 400   args[1] = sound;
 401   Frun_hook_with_args (make_number (2), args);
 402
 403   vox_init (&sd);
 404   sd.open (&sd);
 405
 406   sf.play (&sf, &sd);
 407   close (sf.fd);
 408   sf.fd = -1;
 409   sd.close (&sd);
 410   sound_device = NULL;
 411   sound_file = NULL;
 412   UNGCPRO;
 413   unbind_to (count, Qnil);
 414   return Qnil;
 415 }
 416
 417 \f
 418 /***********************************************************************
 419                         Byte-order Conversion
 420  ***********************************************************************/
 421
 422 /* Convert 32-bit value VALUE which is in little-endian byte-order
 423    to host byte-order.  */
 424
 425 static u_int32_t
 426 le2hl (value)
 427      u_int32_t value;
 428 {
 429 #ifdef WORDS_BIG_ENDIAN
 430   unsigned char *p = (unsigned char *) &value;
 431   value = p[0] + (p[1] << 8) + (p[2] << 16) + (p[3] << 24);
 432 #endif
 433   return value;
 434 }
 435
 436
 437 /* Convert 16-bit value VALUE which is in little-endian byte-order
 438    to host byte-order.  */
 439
 440 static u_int16_t
 441 le2hs (value)
 442      u_int16_t value;
 443 {
 444 #ifdef WORDS_BIG_ENDIAN
 445   unsigned char *p = (unsigned char *) &value;
 446   value = p[0] + (p[1] << 8);
 447 #endif
 448   return value;
 449 }
 450
 451
 452 /* Convert 32-bit value VALUE which is in big-endian byte-order
 453    to host byte-order.  */
 454
 455 static u_int32_t
 456 be2hl (value)
 457      u_int32_t value;
 458 {
 459 #ifndef WORDS_BIG_ENDIAN
 460   unsigned char *p = (unsigned char *) &value;
 461   value = p[3] + (p[2] << 8) + (p[1] << 16) + (p[0] << 24);
 462 #endif
 463   return value;
 464 }
 465
 466
 467 /* Convert 16-bit value VALUE which is in big-endian byte-order
 468    to host byte-order.  */
 469
 470 static u_int16_t
 471 be2hs (value)
 472      u_int16_t value;
 473 {
 474 #ifndef WORDS_BIG_ENDIAN
 475   unsigned char *p = (unsigned char *) &value;
 476   value = p[1] + (p[0] << 8);
 477 #endif
 478   return value;
 479 }
 480
 481
 482 \f
 483 /***********************************************************************
 484                           RIFF-WAVE (*.wav)
 485  ***********************************************************************/
 486
 487 /* Try to initialize sound file SF from SF->header.  SF->header
 488    contains the first MAX_SOUND_HEADER_BYTES number of bytes from the
 489    sound file.  If the file is a WAV-format file, set up interface
 490    functions in SF and convert header fields to host byte-order.
 491    Value is non-zero if the file is a WAV file.  */
 492
 493 static int
 494 wav_init (sf)
 495      struct sound_file *sf;
 496 {
 497   struct wav_header *header = (struct wav_header *) sf->header;
 498
 499   if (bcmp (sf->header, "RIFF", 4) != 0)
 500     return 0;
 501
 502   /* WAV files are in little-endian order.  Convert the header
 503      if on a big-endian machine.  */
 504   header->magic = le2hl (header->magic);
 505   header->length = le2hl (header->length);
 506   header->chunk_type = le2hl (header->chunk_type);
 507   header->chunk_format = le2hl (header->chunk_format);
 508   header->chunk_length = le2hl (header->chunk_length);
 509   header->format = le2hs (header->format);
 510   header->channels = le2hs (header->channels);
 511   header->sample_rate = le2hl (header->sample_rate);
 512   header->bytes_per_second = le2hl (header->bytes_per_second);
 513   header->sample_size = le2hs (header->sample_size);
 514   header->precision = le2hs (header->precision);
 515   header->chunk_data = le2hl (header->chunk_data);
 516   header->data_length = le2hl (header->data_length);
 517
 518   /* Set up the interface functions for WAV.  */
 519   sf->type = RIFF;
 520   sf->play = wav_play;
 521
 522   return 1;
 523 }
 524
 525
 526 /* Play RIFF-WAVE audio file SF on sound device SD.  */
 527
 528 static void
 529 wav_play (sf, sd)
 530      struct sound_file *sf;
 531      struct sound_device *sd;
 532 {
 533   struct wav_header *header = (struct wav_header *) sf->header;
 534   char *buffer;
 535   int nbytes;
 536   int blksize = 2048;
 537
 538   /* Let the device choose a suitable device-dependent format
 539      for the file.  */
 540   sd->choose_format (sd, sf);
 541
 542   /* Configure the device.  */
 543   sd->sample_size = header->sample_size;
 544   sd->sample_rate = header->sample_rate;
 545   sd->bps = header->bytes_per_second;
 546   sd->channels = header->channels;
 547   sd->configure (sd);
 548
 549   /* Copy sound data to the device.  The WAV file specification is
 550      actually more complex.  This simple scheme worked with all WAV
 551      files I found so far.  If someone feels inclined to implement the
 552      whole RIFF-WAVE spec, please do.  */
 553   buffer = (char *) alloca (blksize);
 554   lseek (sf->fd, sizeof *header, SEEK_SET);
 555
 556   while ((nbytes = read (sf->fd, buffer, blksize)) > 0)
 557     sd->write (sd, buffer, nbytes);
 558
 559   if (nbytes < 0)
 560     sound_perror ("Reading sound file");
 561 }
 562
 563
 564 \f
 565 /***********************************************************************
 566                            Sun Audio (*.au)
 567  ***********************************************************************/
 568
 569 /* Sun audio file encodings.  */
 570
 571 enum au_encoding
 572 {
 573   AU_ENCODING_ULAW_8 = 1,
 574   AU_ENCODING_8,
 575   AU_ENCODING_16,
 576   AU_ENCODING_24,
 577   AU_ENCODING_32,
 578   AU_ENCODING_IEEE32,
 579   AU_ENCODING_IEEE64,
 580   AU_COMPRESSED = 23
 581 };
 582
 583
 584 /* Try to initialize sound file SF from SF->header.  SF->header
 585    contains the first MAX_SOUND_HEADER_BYTES number of bytes from the
 586    sound file.  If the file is a AU-format file, set up interface
 587    functions in SF and convert header fields to host byte-order.
 588    Value is non-zero if the file is an AU file.  */
 589
 590 static int
 591 au_init (sf)
 592      struct sound_file *sf;
 593 {
 594   struct au_header *header = (struct au_header *) sf->header;
 595
 596   if (bcmp (sf->header, ".snd", 4) != 0)
 597     return 0;
 598
 599   header->magic_number = be2hl (header->magic_number);
 600   header->data_offset = be2hl (header->data_offset);
 601   header->data_size = be2hl (header->data_size);
 602   header->encoding = be2hl (header->encoding);
 603   header->sample_rate = be2hl (header->sample_rate);
 604   header->channels = be2hl (header->channels);
 605
 606   /* Set up the interface functions for AU.  */
 607   sf->type = SUN_AUDIO;
 608   sf->play = au_play;
 609
 610   return 1;
 611 }
 612
 613
 614 /* Play Sun audio file SF on sound device SD.  */
 615
 616 static void
 617 au_play (sf, sd)
 618      struct sound_file *sf;
 619      struct sound_device *sd;
 620 {
 621   struct au_header *header = (struct au_header *) sf->header;
 622   int blksize = 2048;
 623   char *buffer;
 624   int nbytes;
 625
 626   sd->sample_size = 0;
 627   sd->sample_rate = header->sample_rate;
 628   sd->bps = 0;
 629   sd->channels = header->channels;
 630   sd->choose_format (sd, sf);
 631   sd->configure (sd);
 632
 633   /* Seek */
 634   lseek (sf->fd, header->data_offset, SEEK_SET);
 635
 636   /* Copy sound data to the device.  */
 637   buffer = (char *) alloca (blksize);
 638   while ((nbytes = read (sf->fd, buffer, blksize)) > 0)
 639     sd->write (sd, buffer, nbytes);
 640
 641   if (nbytes < 0)
 642     sound_perror ("Reading sound file");
 643 }
 644
 645
 646 \f
 647 /***********************************************************************
 648                        Voxware Driver Interface
 649  ***********************************************************************/
 650
 651 /* This driver is available on GNU/Linux, and the free BSDs.  FreeBSD
 652    has a compatible own driver aka Luigi's driver.  */
 653
 654
 655 /* Open device SD.  If SD->file is non-null, open that device,
 656    otherwise use a default device name.  */
 657
 658 static void
 659 vox_open (sd)
 660      struct sound_device *sd;
 661 {
 662   char *file;
 663
 664   /* Open the sound device.  Default is /dev/dsp.  */
 665   if (sd->file)
 666     file = sd->file;
 667   else
 668     file = "/dev/dsp";
 669
 670   sd->fd = open (file, O_WRONLY);
 671   if (sd->fd < 0)
 672     sound_perror (file);
 673 }
 674
 675
 676 /* Configure device SD from parameters in it.  */
 677
 678 static void
 679 vox_configure (sd)
 680      struct sound_device *sd;
 681 {
 682   int requested;
 683
 684   xassert (sd->fd >= 0);
 685
 686   /* Device parameters apparently depend on each other in undocumented
 687      ways (not to imply that there is any real documentation).  Be
 688      careful when reordering the calls below.  */
 689   if (sd->sample_size > 0
 690       && ioctl (sd->fd, SNDCTL_DSP_SAMPLESIZE, &sd->sample_size) < 0)
 691     sound_perror ("Setting sample size");
 692
 693   if (sd->bps > 0
 694       && ioctl (sd->fd, SNDCTL_DSP_SPEED, &sd->bps) < 0)
 695     sound_perror ("Setting speed");
 696
 697   if (sd->sample_rate > 0
 698       && ioctl (sd->fd, SOUND_PCM_WRITE_RATE, &sd->sample_rate) < 0)
 699     sound_perror ("Setting sample rate");
 700
 701   requested = sd->format;
 702   if (ioctl (sd->fd, SNDCTL_DSP_SETFMT, &sd->format) < 0)
 703     sound_perror ("Setting format");
 704   else if (requested != sd->format)
 705     error ("Setting format");
 706
 707   if (sd->channels > 1
 708       && ioctl (sd->fd, SNDCTL_DSP_STEREO, &sd->channels) < 0)
 709     sound_perror ("Setting channels");
 710
 711   if (sd->volume > 0
 712       && ioctl (sd->fd, SOUND_MIXER_WRITE_PCM, &sd->volume) < 0)
 713     sound_perror ("Setting volume");
 714 }
 715
 716
 717 /* Close device SD if it is open.  */
 718
 719 static void
 720 vox_close (sd)
 721      struct sound_device *sd;
 722 {
 723   if (sd->fd >= 0)
 724     {
 725       /* Flush sound data, and reset the device.  */
 726       ioctl (sd->fd, SNDCTL_DSP_SYNC, NULL);
 727       ioctl (sd->fd, SNDCTL_DSP_RESET, NULL);
 728
 729       /* Close the device.  */
 730       close (sd->fd);
 731       sd->fd = -1;
 732     }
 733 }
 734
 735
 736 /* Choose device-dependent format for device SD from sound file SF.  */
 737
 738 static void
 739 vox_choose_format (sd, sf)
 740      struct sound_device *sd;
 741      struct sound_file *sf;
 742 {
 743   if (sf->type == RIFF)
 744     {
 745       struct wav_header *h = (struct wav_header *) sf->header;
 746       if (h->precision == 8)
 747         sd->format = AFMT_U8;
 748       else if (h->precision == 16)
 749         sd->format = AFMT_S16_LE;
 750       else
 751         error ("Unsupported WAV file format");
 752     }
 753   else if (sf->type == SUN_AUDIO)
 754     {
 755       struct au_header *header = (struct au_header *) sf->header;
 756       switch (header->encoding)
 757         {
 758         case AU_ENCODING_ULAW_8:
 759         case AU_ENCODING_IEEE32:
 760         case AU_ENCODING_IEEE64:
 761           sd->format = AFMT_MU_LAW;
 762           break;
 763
 764         case AU_ENCODING_8:
 765         case AU_ENCODING_16:
 766         case AU_ENCODING_24:
 767         case AU_ENCODING_32:
 768           sd->format = AFMT_S16_LE;
 769           break;
 770
 771         default:
 772           error ("Unsupported AU file format");
 773         }
 774     }
 775   else
 776     abort ();
 777 }
 778
 779
 780 /* Initialize device SD.  Set up the interface functions in the device
 781    structure.  */
 782
 783 static void
 784 vox_init (sd)
 785      struct sound_device *sd;
 786 {
 787   sd->fd = -1;
 788   sd->open = vox_open;
 789   sd->close = vox_close;
 790   sd->configure = vox_configure;
 791   sd->choose_format = vox_choose_format;
 792   sd->write = vox_write;
 793 }
 794
 795
 796 /* Write NBYTES bytes from BUFFER to device SD.  */
 797
 798 static void
 799 vox_write (sd, buffer, nbytes)
 800      struct sound_device *sd;
 801      char *buffer;
 802      int nbytes;
 803 {
 804   int nwritten = write (sd->fd, buffer, nbytes);
 805   if (nwritten < 0)
 806     sound_perror ("Writing to sound device");
 807 }
 808
 809
 810 \f
 811 /***********************************************************************
 812                             Initialization
 813  ***********************************************************************/
 814
 815 void
 816 syms_of_sound ()
 817 {
 818   QCdevice = intern (":device");
 819   staticpro (&QCdevice);
 820   QCvolume = intern (":volume");
 821   staticpro (&QCvolume);
 822   Qsound = intern ("sound");
 823   staticpro (&Qsound);
 824   Qplay_sound_functions = intern ("play-sound-functions");
 825   staticpro (&Qplay_sound_functions);
 826
 827   defsubr (&Splay_sound);
 828 }
 829
 830
 831 void
 832 init_sound ()
 833 {
 834 }
 835
 836 #endif /* HAVE_SOUND */