formats/format_vox.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 1999 - 2005, Digium, Inc.
   5  *
   6  * Mark Spencer <markster@digium.com>
   7  *
   8  * See http://www.asterisk.org for more information about
   9  * the Asterisk project. Please do not directly contact
  10  * any of the maintainers of this project for assistance;
  11  * the project provides a web site, mailing lists and IRC
  12  * channels for your use.
  13  *
  14  * This program is free software, distributed under the terms of
  15  * the GNU General Public License Version 2. See the LICENSE file
  16  * at the top of the source tree.
  17  */
  18
  19 /*! \file
  20  *
  21  * \brief Flat, binary, ADPCM vox file format.
  22  * \arg File name extensions: vox
  23  *
  24  * \ingroup formats
  25  */
  26
  27 #include "asterisk.h"
  28
  29 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  30
  31 #include <unistd.h>
  32 #include <netinet/in.h>
  33 #include <arpa/inet.h>
  34 #include <stdlib.h>
  35 #include <sys/time.h>
  36 #include <stdio.h>
  37 #include <errno.h>
  38 #include <string.h>
  39
  40 #include "asterisk/lock.h"
  41 #include "asterisk/channel.h"
  42 #include "asterisk/file.h"
  43 #include "asterisk/logger.h"
  44 #include "asterisk/sched.h"
  45 #include "asterisk/module.h"
  46 #include "asterisk/endian.h"
  47
  48 #define BUF_SIZE        80              /* 80 bytes, 160 samples */
  49 #define VOX_SAMPLES     160
  50
  51 static struct ast_frame *vox_read(struct ast_filestream *s, int *whennext)
  52 {
  53         int res;
  54
  55         /* Send a frame from the file to the appropriate channel */
  56         s->fr.frametype = AST_FRAME_VOICE;
  57         s->fr.subclass = AST_FORMAT_ADPCM;
  58         s->fr.mallocd = 0;
  59         AST_FRAME_SET_BUFFER(&s->fr, s->buf, AST_FRIENDLY_OFFSET, BUF_SIZE);
  60         if ((res = fread(s->fr.data, 1, s->fr.datalen, s->f)) < 1) {
  61                 if (res)
  62                         ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
  63                 return NULL;
  64         }
  65         *whennext = s->fr.samples = res * 2;
  66         s->fr.datalen = res;
  67         return &s->fr;
  68 }
  69
  70 static int vox_write(struct ast_filestream *s, struct ast_frame *f)
  71 {
  72         int res;
  73         if (f->frametype != AST_FRAME_VOICE) {
  74                 ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
  75                 return -1;
  76         }
  77         if (f->subclass != AST_FORMAT_ADPCM) {
  78                 ast_log(LOG_WARNING, "Asked to write non-ADPCM frame (%d)!\n", f->subclass);
  79                 return -1;
  80         }
  81         if ((res = fwrite(f->data, 1, f->datalen, s->f)) != f->datalen) {
  82                         ast_log(LOG_WARNING, "Bad write (%d/%d): %s\n", res, f->datalen, strerror(errno));
  83                         return -1;
  84         }
  85         return 0;
  86 }
  87
  88 static int vox_seek(struct ast_filestream *fs, off_t sample_offset, int whence)
  89 {
  90      off_t offset=0,min,cur,max,distance;
  91
  92      min = 0;
  93      cur = ftello(fs->f);
  94      fseeko(fs->f, 0, SEEK_END);
  95          max = ftello(fs->f);
  96
  97      /* have to fudge to frame here, so not fully to sample */
  98      distance = sample_offset/2;
  99      if(whence == SEEK_SET)
 100           offset = distance;
 101      else if(whence == SEEK_CUR || whence == SEEK_FORCECUR)
 102           offset = distance + cur;
 103      else if(whence == SEEK_END)
 104           offset = max - distance;
 105      if (whence != SEEK_FORCECUR) {
 106           offset = (offset > max)?max:offset;
 107           offset = (offset < min)?min:offset;
 108      }
 109      return fseeko(fs->f, offset, SEEK_SET);
 110 }
 111
 112 static int vox_trunc(struct ast_filestream *fs)
 113 {
 114      return ftruncate(fileno(fs->f), ftello(fs->f));
 115 }
 116
 117 static off_t vox_tell(struct ast_filestream *fs)
 118 {
 119      off_t offset;
 120      offset = ftello(fs->f) << 1;
 121      return offset;
 122 }
 123
 124 static const struct ast_format vox_f = {
 125         .name = "vox",
 126         .exts = "vox",
 127         .format = AST_FORMAT_ADPCM,
 128         .write = vox_write,
 129         .seek = vox_seek,
 130         .trunc = vox_trunc,
 131         .tell = vox_tell,
 132         .read = vox_read,
 133         .buf_size = BUF_SIZE + AST_FRIENDLY_OFFSET,
 134 };
 135
 136 static int load_module(void)
 137 {
 138         return ast_format_register(&vox_f);
 139 }
 140
 141 static int unload_module(void)
 142 {
 143         return ast_format_unregister(vox_f.name);
 144 }
 145
 146 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Dialogic VOX (ADPCM) File Format");