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_hook;
 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.  */
 264
 265 static int
 266 parse_sound (sound, attrs)
 267      Lisp_Object sound;
 268      Lisp_Object *attrs;
 269 {
 270   /* SOUND must be a list starting with the symbol `sound'.  */
 271   if (!CONSP (sound) || !EQ (XCAR (sound), Qsound))
 272     return 0;
 273
 274   sound = XCDR (sound);
 275   attrs[SOUND_FILE] = Fplist_get (sound, QCfile);
 276   attrs[SOUND_DEVICE] = Fplist_get (sound, QCdevice);
 277   attrs[SOUND_VOLUME] = Fplist_get (sound, QCvolume);
 278
 279   /* File name must be specified.  */
 280   if (!STRINGP (attrs[SOUND_FILE]))
 281     return 0;
 282
 283   /* Volume must be in the range 0..100 or unspecified.  */
 284   if (!NILP (attrs[SOUND_VOLUME]))
 285     {
 286       if (!INTEGERP (attrs[SOUND_VOLUME]))
 287         return 0;
 288       if (XINT (attrs[SOUND_VOLUME]) < 0
 289           || XINT (attrs[SOUND_VOLUME]) > 100)
 290         return 0;
 291     }
 292
 293   /* Device must be a string or unspecified.  */
 294   if (!NILP (attrs[SOUND_DEVICE])
 295       && !STRINGP (attrs[SOUND_DEVICE]))
 296     return 0;
 297
 298   return 1;
 299 }
 300
 301
 302 /* Find out the type of the sound file whose file descriptor is FD.
 303    SF is the sound file structure to fill in.  */
 304
 305 static void
 306 find_sound_file_type (sf)
 307      struct sound_file *sf;
 308 {
 309   if (!wav_init (sf)
 310       && !au_init (sf))
 311     error ("Unknown sound file format");
 312 }
 313
 314
 315 /* Function installed by play-sound with record_unwind_protect.  */
 316
 317 static Lisp_Object
 318 sound_cleanup (arg)
 319      Lisp_Object arg;
 320 {
 321   if (sound_device)
 322     {
 323       sound_device->close (sound_device);
 324       if (sound_file->fd > 0)
 325         close (sound_file->fd);
 326     }
 327 }
 328
 329
 330 DEFUN ("play-sound", Fplay_sound, Splay_sound, 1, 1, 0,
 331   "Play sound SOUND.")
 332   (sound)
 333      Lisp_Object sound;
 334 {
 335   Lisp_Object attrs[SOUND_ATTR_SENTINEL];
 336   char *header;
 337   Lisp_Object file;
 338   struct gcpro gcpro1, gcpro2;
 339   int nbytes;
 340   char *msg;
 341   struct sound_device sd;
 342   struct sound_file sf;
 343   Lisp_Object args[2];
 344   int count = specpdl_ptr - specpdl;
 345
 346   file = Qnil;
 347   GCPRO2 (sound, file);
 348   bzero (&sd, sizeof sd);
 349   bzero (&sf, sizeof sf);
 350   sf.header = (char *) alloca (MAX_SOUND_HEADER_BYTES);
 351
 352   sound_device = &sd;
 353   sound_file = &sf;
 354   record_unwind_protect (sound_cleanup, Qnil);
 355
 356   /* Parse the sound specification.  Give up if it is invalid.  */
 357   if (!parse_sound (sound, attrs))
 358     {
 359       UNGCPRO;
 360       error ("Invalid sound specification");
 361     }
 362
 363   /* Open the sound file.  */
 364   sf.fd = openp (Fcons (Vdata_directory, Qnil),
 365                  attrs[SOUND_FILE], "", &file, 0);
 366   if (sf.fd < 0)
 367     sound_perror ("Open sound file");
 368
 369   /* Read the first bytes from the file.  */
 370   nbytes = read (sf.fd, sf.header, MAX_SOUND_HEADER_BYTES);
 371   if (nbytes < 0)
 372     sound_perror ("Reading sound file header");
 373
 374   /* Find out the type of sound file.  Give up if we can't tell.  */
 375   find_sound_file_type (&sf);
 376
 377   /* Set up a device.  */
 378   if (STRINGP (attrs[SOUND_DEVICE]))
 379     {
 380       int len = XSTRING (attrs[SOUND_DEVICE])->size;
 381       sd.file = (char *) alloca (len + 1);
 382       strcpy (sd.file, XSTRING (attrs[SOUND_DEVICE])->data);
 383     }
 384   if (INTEGERP (attrs[SOUND_VOLUME]))
 385     sd.volume = XFASTINT (attrs[SOUND_VOLUME]);
 386
 387   args[0] = Qplay_sound_hook;
 388   args[1] = sound;
 389   Frun_hook_with_args (make_number (2), args);
 390
 391   vox_init (&sd);
 392   sd.open (&sd);
 393
 394   sf.play (&sf, &sd);
 395   close (sf.fd);
 396   sf.fd = -1;
 397   sd.close (&sd);
 398   sound_device = NULL;
 399   sound_file = NULL;
 400   UNGCPRO;
 401   unbind_to (count, Qnil);
 402   return Qnil;
 403 }
 404
 405 \f
 406 /***********************************************************************
 407                         Byte-order Conversion
 408  ***********************************************************************/
 409
 410 /* Convert 32-bit value VALUE which is in little-endian byte-order
 411    to host byte-order.  */
 412
 413 static u_int32_t
 414 le2hl (value)
 415      u_int32_t value;
 416 {
 417 #ifdef WORDS_BIG_ENDIAN
 418   unsigned char *p = (unsigned char *) &value;
 419   value = p[0] + (p[1] << 8) + (p[2] << 16) + (p[3] << 24);
 420 #endif
 421   return value;
 422 }
 423
 424
 425 /* Convert 16-bit value VALUE which is in little-endian byte-order
 426    to host byte-order.  */
 427
 428 static u_int16_t
 429 le2hs (value)
 430      u_int16_t value;
 431 {
 432 #ifdef WORDS_BIG_ENDIAN
 433   unsigned char *p = (unsigned char *) &value;
 434   value = p[0] + (p[1] << 8);
 435 #endif
 436   return value;
 437 }
 438
 439
 440 /* Convert 32-bit value VALUE which is in big-endian byte-order
 441    to host byte-order.  */
 442
 443 static u_int32_t
 444 be2hl (value)
 445      u_int32_t value;
 446 {
 447 #ifndef WORDS_BIG_ENDIAN
 448   unsigned char *p = (unsigned char *) &value;
 449   value = p[3] + (p[2] << 8) + (p[1] << 16) + (p[0] << 24);
 450 #endif
 451   return value;
 452 }
 453
 454
 455 /* Convert 16-bit value VALUE which is in big-endian byte-order
 456    to host byte-order.  */
 457
 458 static u_int16_t
 459 be2hs (value)
 460      u_int16_t value;
 461 {
 462 #ifndef WORDS_BIG_ENDIAN
 463   unsigned char *p = (unsigned char *) &value;
 464   value = p[1] + (p[0] << 8);
 465 #endif
 466   return value;
 467 }
 468
 469
 470 \f
 471 /***********************************************************************
 472                           RIFF-WAVE (*.wav)
 473  ***********************************************************************/
 474
 475 /* Try to initialize sound file SF from SF->header.  SF->header
 476    contains the first MAX_SOUND_HEADER_BYTES number of bytes from the
 477    sound file.  If the file is a WAV-format file, set up interface
 478    functions in SF and convert header fields to host byte-order.
 479    Value is non-zero if the file is a WAV file.  */
 480
 481 static int
 482 wav_init (sf)
 483      struct sound_file *sf;
 484 {
 485   struct wav_header *header = (struct wav_header *) sf->header;
 486
 487   if (bcmp (sf->header, "RIFF", 4) != 0)
 488     return 0;
 489
 490   /* WAV files are in little-endian order.  Convert the header
 491      if on a big-endian machine.  */
 492   header->magic = le2hl (header->magic);
 493   header->length = le2hl (header->length);
 494   header->chunk_type = le2hl (header->chunk_type);
 495   header->chunk_format = le2hl (header->chunk_format);
 496   header->chunk_length = le2hl (header->chunk_length);
 497   header->format = le2hs (header->format);
 498   header->channels = le2hs (header->channels);
 499   header->sample_rate = le2hl (header->sample_rate);
 500   header->bytes_per_second = le2hl (header->bytes_per_second);
 501   header->sample_size = le2hs (header->sample_size);
 502   header->precision = le2hs (header->precision);
 503   header->chunk_data = le2hl (header->chunk_data);
 504   header->data_length = le2hl (header->data_length);
 505
 506   /* Set up the interface functions for WAV.  */
 507   sf->type = RIFF;
 508   sf->play = wav_play;
 509
 510   return 1;
 511 }
 512
 513
 514 /* Play RIFF-WAVE audio file SF on sound device SD.  */
 515
 516 static void
 517 wav_play (sf, sd)
 518      struct sound_file *sf;
 519      struct sound_device *sd;
 520 {
 521   struct wav_header *header = (struct wav_header *) sf->header;
 522   char *buffer;
 523   int nbytes;
 524   int blksize = 2048;
 525
 526   /* Let the device choose a suitable device-dependent format
 527      for the file.  */
 528   sd->choose_format (sd, sf);
 529
 530   /* Configure the device.  */
 531   sd->sample_size = header->sample_size;
 532   sd->sample_rate = header->sample_rate;
 533   sd->bps = header->bytes_per_second;
 534   sd->channels = header->channels;
 535   sd->configure (sd);
 536
 537   /* Copy sound data to the device.  The WAV file specification is
 538      actually more complex.  This simple scheme worked with all WAV
 539      files I found so far.  If someone feels inclined to implement the
 540      whole RIFF-WAVE spec, please do.  */
 541   buffer = (char *) alloca (blksize);
 542   lseek (sf->fd, sizeof *header, SEEK_SET);
 543
 544   while ((nbytes = read (sf->fd, buffer, blksize)) > 0)
 545     sd->write (sd, buffer, nbytes);
 546
 547   if (nbytes < 0)
 548     sound_perror ("Reading sound file");
 549 }
 550
 551
 552 \f
 553 /***********************************************************************
 554                            Sun Audio (*.au)
 555  ***********************************************************************/
 556
 557 /* Sun audio file encodings.  */
 558
 559 enum au_encoding
 560 {
 561   AU_ENCODING_ULAW_8 = 1,
 562   AU_ENCODING_8,
 563   AU_ENCODING_16,
 564   AU_ENCODING_24,
 565   AU_ENCODING_32,
 566   AU_ENCODING_IEEE32,
 567   AU_ENCODING_IEEE64,
 568   AU_COMPRESSED = 23
 569 };
 570
 571
 572 /* Try to initialize sound file SF from SF->header.  SF->header
 573    contains the first MAX_SOUND_HEADER_BYTES number of bytes from the
 574    sound file.  If the file is a AU-format file, set up interface
 575    functions in SF and convert header fields to host byte-order.
 576    Value is non-zero if the file is an AU file.  */
 577
 578 static int
 579 au_init (sf)
 580      struct sound_file *sf;
 581 {
 582   struct au_header *header = (struct au_header *) sf->header;
 583
 584   if (bcmp (sf->header, ".snd", 4) != 0)
 585     return 0;
 586
 587   header->magic_number = be2hl (header->magic_number);
 588   header->data_offset = be2hl (header->data_offset);
 589   header->data_size = be2hl (header->data_size);
 590   header->encoding = be2hl (header->encoding);
 591   header->sample_rate = be2hl (header->sample_rate);
 592   header->channels = be2hl (header->channels);
 593
 594   /* Set up the interface functions for AU.  */
 595   sf->type = SUN_AUDIO;
 596   sf->play = au_play;
 597
 598   return 1;
 599 }
 600
 601
 602 /* Play Sun audio file SF on sound device SD.  */
 603
 604 static void
 605 au_play (sf, sd)
 606      struct sound_file *sf;
 607      struct sound_device *sd;
 608 {
 609   struct au_header *header = (struct au_header *) sf->header;
 610   int blksize = 2048;
 611   char *buffer;
 612   int nbytes;
 613
 614   sd->sample_size = 0;
 615   sd->sample_rate = header->sample_rate;
 616   sd->bps = 0;
 617   sd->channels = header->channels;
 618   sd->choose_format (sd, sf);
 619   sd->configure (sd);
 620
 621   /* Seek */
 622   lseek (sf->fd, header->data_offset, SEEK_SET);
 623
 624   /* Copy sound data to the device.  */
 625   buffer = (char *) alloca (blksize);
 626   while ((nbytes = read (sf->fd, buffer, blksize)) > 0)
 627     sd->write (sd, buffer, nbytes);
 628
 629   if (nbytes < 0)
 630     sound_perror ("Reading sound file");
 631 }
 632
 633
 634 \f
 635 /***********************************************************************
 636                        Voxware Driver Interface
 637  ***********************************************************************/
 638
 639 /* This driver is available on GNU/Linux, and the free BSDs.  FreeBSD
 640    has a compatible own driver aka Luigi's driver.  */
 641
 642
 643 /* Open device SD.  If SD->file is non-null, open that device,
 644    otherwise use a default device name.  */
 645
 646 static void
 647 vox_open (sd)
 648      struct sound_device *sd;
 649 {
 650   char *file;
 651
 652   /* Open the sound device.  Default is /dev/dsp.  */
 653   if (sd->file)
 654     file = sd->file;
 655   else
 656     file = "/dev/dsp";
 657
 658   sd->fd = open (file, O_WRONLY);
 659   if (sd->fd < 0)
 660     sound_perror (file);
 661 }
 662
 663
 664 /* Configure device SD from parameters in it.  */
 665
 666 static void
 667 vox_configure (sd)
 668      struct sound_device *sd;
 669 {
 670   int requested;
 671
 672   xassert (sd->fd >= 0);
 673
 674   /* Device parameters apparently depend on each other in undocumented
 675      ways (not to imply that there is any real documentation).  Be
 676      careful when reordering the calls below.  */
 677   if (sd->sample_size > 0
 678       && ioctl (sd->fd, SNDCTL_DSP_SAMPLESIZE, &sd->sample_size) < 0)
 679     sound_perror ("Setting sample size");
 680
 681   if (sd->bps > 0
 682       && ioctl (sd->fd, SNDCTL_DSP_SPEED, &sd->bps) < 0)
 683     sound_perror ("Setting speed");
 684
 685   if (sd->sample_rate > 0
 686       && ioctl (sd->fd, SOUND_PCM_WRITE_RATE, &sd->sample_rate) < 0)
 687     sound_perror ("Setting sample rate");
 688
 689   requested = sd->format;
 690   if (ioctl (sd->fd, SNDCTL_DSP_SETFMT, &sd->format) < 0)
 691     sound_perror ("Setting format");
 692   else if (requested != sd->format)
 693     error ("Setting format");
 694
 695   if (sd->channels > 1
 696       && ioctl (sd->fd, SNDCTL_DSP_STEREO, &sd->channels) < 0)
 697     sound_perror ("Setting channels");
 698
 699   if (sd->volume > 0
 700       && ioctl (sd->fd, SOUND_MIXER_WRITE_PCM, &sd->volume) < 0)
 701     sound_perror ("Setting volume");
 702 }
 703
 704
 705 /* Close device SD if it is open.  */
 706
 707 static void
 708 vox_close (sd)
 709      struct sound_device *sd;
 710 {
 711   if (sd->fd >= 0)
 712     {
 713       /* Flush sound data, and reset the device.  */
 714       ioctl (sd->fd, SNDCTL_DSP_SYNC, NULL);
 715       ioctl (sd->fd, SNDCTL_DSP_RESET, NULL);
 716
 717       /* Close the device.  */
 718       close (sd->fd);
 719       sd->fd = -1;
 720     }
 721 }
 722
 723
 724 /* Choose device-dependent format for device SD from sound file SF.  */
 725
 726 static void
 727 vox_choose_format (sd, sf)
 728      struct sound_device *sd;
 729      struct sound_file *sf;
 730 {
 731   if (sf->type == RIFF)
 732     {
 733       struct wav_header *h = (struct wav_header *) sf->header;
 734       if (h->precision == 8)
 735         sd->format = AFMT_U8;
 736       else if (h->precision == 16)
 737         sd->format = AFMT_S16_LE;
 738       else
 739         error ("Unsupported WAV file format");
 740     }
 741   else if (sf->type == SUN_AUDIO)
 742     {
 743       struct au_header *header = (struct au_header *) sf->header;
 744       switch (header->encoding)
 745         {
 746         case AU_ENCODING_ULAW_8:
 747         case AU_ENCODING_IEEE32:
 748         case AU_ENCODING_IEEE64:
 749           sd->format = AFMT_MU_LAW;
 750           break;
 751
 752         case AU_ENCODING_8:
 753         case AU_ENCODING_16:
 754         case AU_ENCODING_24:
 755         case AU_ENCODING_32:
 756           sd->format = AFMT_S16_LE;
 757           break;
 758
 759         default:
 760           error ("Unsupported AU file format");
 761         }
 762     }
 763   else
 764     abort ();
 765 }
 766
 767
 768 /* Initialize device SD.  Set up the interface functions in the device
 769    structure.  */
 770
 771 static void
 772 vox_init (sd)
 773      struct sound_device *sd;
 774 {
 775   sd->fd = -1;
 776   sd->open = vox_open;
 777   sd->close = vox_close;
 778   sd->configure = vox_configure;
 779   sd->choose_format = vox_choose_format;
 780   sd->write = vox_write;
 781 }
 782
 783
 784 /* Write NBYTES bytes from BUFFER to device SD.  */
 785
 786 static void
 787 vox_write (sd, buffer, nbytes)
 788      struct sound_device *sd;
 789      char *buffer;
 790      int nbytes;
 791 {
 792   int nwritten = write (sd->fd, buffer, nbytes);
 793   if (nwritten < 0)
 794     sound_perror ("Writing to sound device");
 795 }
 796
 797
 798 \f
 799 /***********************************************************************
 800                             Initialization
 801  ***********************************************************************/
 802
 803 void
 804 syms_of_sound ()
 805 {
 806   QCdevice = intern (":device");
 807   staticpro (&QCdevice);
 808   QCvolume = intern (":volume");
 809   staticpro (&QCvolume);
 810   Qsound = intern ("sound");
 811   staticpro (&Qsound);
 812   Qplay_sound_hook = intern ("play-sound-hook");
 813   staticpro (&Qplay_sound_hook);
 814
 815   defsubr (&Splay_sound);
 816 }
 817
 818
 819 void
 820 init_sound ()
 821 {
 822 }
 823
 824 #endif /* HAVE_SOUND */