text: /*
  ** Copyright (C) 2004-2012 Erik de Castro Lopo <erikd@mega-nerd.com>
  **
  ** This program is free software; you can redistribute it and/or modify
  ** it under the terms of the GNU Lesser General Public License as published by
  ** the Free Software Foundation; either version 2.1 of the License, or
  ** (at your option) any later version.
  **
  ** This program is distributed in the hope that it will be useful,
  ** but WITHOUT ANY WARRANTY; without even the implied warranty of
  ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  ** GNU Lesser General Public License for more details.
  **
  ** You should have received a copy of the GNU Lesser General Public License
  ** along with this program; if not, write to the Free Software
  ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
  
  #include "sfconfig.h"
  
  #include <stdio.h>
  #include <string.h>
  
  #include "sndfile.h"
  #include "sfendian.h"
  #include "common.h"
  
  #define TWOBIT_MARKER   (MAKE_MARKER ('2', 'B', 'I', 'T'))
  #define AVR_HDR_SIZE    128
  
  #define SFE_AVR_X   666
  
  /*
  ** From: hyc@hanauma.Jpl.Nasa.Gov (Howard Chu)
  **
  ** A lot of PD software exists to play Mac .snd files on the ST. One other
  ** format that seems pretty popular (used by a number of commercial packages)
  ** is the AVR format (from Audio Visual Research). This format has a 128 byte
  ** header that looks like this (its actually packed, but thats not portable):
  */
  
  typedef struct
  {   int     marker ;    /* 2BIT */
      char    name [8] ;  /* null-padded sample name */
      short   mono ;      /* 0 = mono, 0xffff = stereo */
      short   rez ;       /* 8 = 8 bit, 16 = 16 bit */
      short   sign ;      /* 0 = unsigned, 0xffff = signed */
  
      short   loop ;      /* 0 = no loop, 0xffff = looping sample */
      short   midi ;      /* 0xffff = no MIDI note assigned,  */
                          /*  0xffXX = single key note assignment */
                          /*  0xLLHH = key split, low/hi note */
      int     srate ;     /* sample frequency in hertz */
      int     frames ;    /* sample length in bytes or words (see rez) */
      int     lbeg ;      /* offset to start of loop in bytes or words. */
                          /* set to zero if unused */
      int     lend ;      /* offset to end of loop in bytes or words. */
                          /* set to sample length if unused */
      short   res1 ;      /* Reserved, MIDI keyboard split */
      short   res2 ;      /* Reserved, sample compression */
      short   res3 ;      /* Reserved */
      char    ext [20] ;  /* Additional filename space, used if (name[7] != 0) */
      char    user [64] ; /* User defined. Typically ASCII message */
  } AVR_HEADER ;
  
  /*------------------------------------------------------------------------------
  ** Private static functions.
  */
  
  static int      avr_close (SF_PRIVATE *psf) ;
  
  static int      avr_read_header (SF_PRIVATE *psf) ;
  static int      avr_write_header (SF_PRIVATE *psf, int calc_length) ;
  
  /*------------------------------------------------------------------------------
  ** Public function.
  */
  
  int
  avr_open    (SF_PRIVATE *psf)
  {   int     error = 0 ;
  
      if (psf->file.mode == SFM_READ || (psf->file.mode == SFM_RDWR && psf->filelength > 0))
      {   if ((error = avr_read_header (psf)))
              return error ;
          } ;
  
      if ((SF_CONTAINER (psf->sf.format)) != SF_FORMAT_AVR)
          return  SFE_BAD_OPEN_FORMAT ;
  
      if (psf->file.mode == SFM_WRITE || psf->file.mode == SFM_RDWR)
      {   psf->endian = SF_ENDIAN_BIG ;
  
          if (avr_write_header (psf, SF_FALSE))
              return psf->error ;
  
          psf->write_header = avr_write_header ;
          } ;
  
      psf->container_close = avr_close ;
  
      psf->blockwidth = psf->bytewidth * psf->sf.channels ;
  
      error = pcm_init (psf) ;
  
      return error ;
  } /* avr_open */
  
  static int
  avr_read_header (SF_PRIVATE *psf)
  {   AVR_HEADER  hdr ;
  
      memset (&hdr, 0, sizeof (hdr)) ;
  
      psf_binheader_readf (psf, "pmb", 0, &hdr.marker, &hdr.name, sizeof (hdr.name)) ;
      psf_log_printf (psf, "%M\n", hdr.marker) ;
  
      if (hdr.marker != TWOBIT_MARKER)
          return SFE_AVR_X ;
  
      psf_log_printf (psf, "  Name        : %s\n", hdr.name) ;
  
      psf_binheader_readf (psf, "E22222", &hdr.mono, &hdr.rez, &hdr.sign, &hdr.loop, &hdr.midi) ;
  
      psf->sf.channels = (hdr.mono & 1) + 1 ;
  
      psf_log_printf (psf, "  Channels    : %d\n  Bit width   : %d\n  Signed      : %s\n",
              (hdr.mono & 1) + 1, hdr.rez, hdr.sign ? "yes" : "no") ;
  
      switch ((hdr.rez << 16) + (hdr.sign & 1))
      {   case ((8 << 16) + 0) :
              psf->sf.format = SF_FORMAT_AVR | SF_FORMAT_PCM_U8 ;
              psf->bytewidth = 1 ;
              break ;
  
          case ((8 << 16) + 1) :
              psf->sf.format = SF_FORMAT_AVR | SF_FORMAT_PCM_S8 ;
              psf->bytewidth = 1 ;
              break ;
  
          case ((16 << 16) + 1) :
              psf->sf.format = SF_FORMAT_AVR | SF_FORMAT_PCM_16 ;
              psf->bytewidth = 2 ;
              break ;
  
          default :
              psf_log_printf (psf, "Error : bad rez/sign combination.\n") ;
              return SFE_AVR_X ;
          } ;
  
      psf_binheader_readf (psf, "E4444", &hdr.srate, &hdr.frames, &hdr.lbeg, &hdr.lend) ;
  
      psf->sf.frames = hdr.frames ;
      psf->sf.samplerate = hdr.srate ;
  
      psf_log_printf (psf, "  Frames      : %D\n", psf->sf.frames) ;
      psf_log_printf (psf, "  Sample rate : %d\n", psf->sf.samplerate) ;
  
      psf_binheader_readf (psf, "E222", &hdr.res1, &hdr.res2, &hdr.res3) ;
      psf_binheader_readf (psf, "bb", hdr.ext, sizeof (hdr.ext), hdr.user, sizeof (hdr.user)) ;
  
      psf_log_printf (psf, "  Ext         : %s\n  User        : %s\n", hdr.ext, hdr.user) ;
  
      psf->endian = SF_ENDIAN_BIG ;
  
      psf->dataoffset = AVR_HDR_SIZE ;
      psf->datalength = hdr.frames * (hdr.rez / 8) ;
  
      if (psf->fileoffset > 0)
          psf->filelength = AVR_HDR_SIZE + psf->datalength ;
  
      if (psf_ftell (psf) != psf->dataoffset)
          psf_binheader_readf (psf, "j", psf->dataoffset - psf_ftell (psf)) ;
  
      psf->blockwidth = psf->sf.channels * psf->bytewidth ;
  
      if (psf->sf.frames == 0 && psf->blockwidth)
          psf->sf.frames = (psf->filelength - psf->dataoffset) / psf->blockwidth ;
  
      return 0 ;
  } /* avr_read_header */
  
  static int
  avr_write_header (SF_PRIVATE *psf, int calc_length)
  {   sf_count_t  current ;
      int         sign ;
  
      if (psf->pipeoffset > 0)
          return 0 ;
  
      current = psf_ftell (psf) ;
  
      if (calc_length)
      {   psf->filelength = psf_get_filelen (psf) ;
  
          psf->datalength = psf->filelength - psf->dataoffset ;
          if (psf->dataend)
              psf->datalength -= psf->filelength - psf->dataend ;
  
          psf->sf.frames = psf->datalength / (psf->bytewidth * psf->sf.channels) ;
          } ;
  
      /* Reset the current header length to zero. */
      psf->header [0] = 0 ;
      psf->headindex = 0 ;
  
      /*
      ** Only attempt to seek if we are not writng to a pipe. If we are
      ** writing to a pipe we shouldn't be here anyway.
      */
      if (psf->is_pipe == SF_FALSE)
          psf_fseek (psf, 0, SEEK_SET) ;
  
      psf_binheader_writef (psf, "Emz22", TWOBIT_MARKER, make_size_t (8),
              psf->sf.channels == 2 ? 0xFFFF : 0, psf->bytewidth * 8) ;
  
      sign = ((SF_CODEC (psf->sf.format)) == SF_FORMAT_PCM_U8) ? 0 : 0xFFFF ;
  
      psf_binheader_writef (psf, "E222", sign, 0, 0xFFFF) ;
      psf_binheader_writef (psf, "E4444", psf->sf.samplerate, psf->sf.frames, 0, 0) ;
  
      psf_binheader_writef (psf, "E222zz", 0, 0, 0, make_size_t (20), make_size_t (64)) ;
  
      /* Header construction complete so write it out. */
      psf_fwrite (psf->header, psf->headindex, 1, psf) ;
  
      if (psf->error)
          return psf->error ;
  
      psf->dataoffset = psf->headindex ;
  
      if (current > 0)
          psf_fseek (psf, current, SEEK_SET) ;
  
      return psf->error ;
  } /* avr_write_header */
  
  static int
  avr_close (SF_PRIVATE *psf)
  {
      if (psf->file.mode == SFM_WRITE || psf->file.mode == SFM_RDWR)
          avr_write_header (psf, SF_TRUE) ;
  
      return 0 ;
  } /* avr_close */
  