formats/format_g729.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 Save to raw, headerless G729 data.
  22  * \note This is not an encoder/decoder. The codec fo g729 is only
  23  * available with a commercial license from Digium, due to patent
  24  * restrictions. Check http://www.digium.com for information.
  25  * \arg Extensions: g729
  26  * \ingroup formats
  27  */
  28
  29 #include "asterisk.h"
  30
  31 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  32
  33 #include <unistd.h>
  34 #include <netinet/in.h>
  35 #include <arpa/inet.h>
  36 #include <stdlib.h>
  37 #include <sys/time.h>
  38 #include <stdio.h>
  39 #include <errno.h>
  40 #include <string.h>
  41
  42 #include "asterisk/lock.h"
  43 #include "asterisk/channel.h"
  44 #include "asterisk/file.h"
  45 #include "asterisk/logger.h"
  46 #include "asterisk/sched.h"
  47 #include "asterisk/module.h"
  48 #include "asterisk/endian.h"
  49
  50 /* Some Ideas for this code came from makeg729e.c by Jeffrey Chilton */
  51
  52 /* Portions of the conversion code are by guido@sienanet.it */
  53
  54 #define BUF_SIZE        20      /* two G729 frames */
  55 #define G729A_SAMPLES   160
  56
  57 static struct ast_frame *g729_read(struct ast_filestream *s, int *whennext)
  58 {
  59         int res;
  60         /* Send a frame from the file to the appropriate channel */
  61         s->fr.frametype = AST_FRAME_VOICE;
  62         s->fr.subclass = AST_FORMAT_G729A;
  63         s->fr.mallocd = 0;
  64         s->fr.samples = G729A_SAMPLES;
  65         AST_FRAME_SET_BUFFER(&s->fr, s->buf, AST_FRIENDLY_OFFSET, BUF_SIZE);
  66         if ((res = fread(s->fr.data, 1, s->fr.datalen, s->f)) != s->fr.datalen) {
  67                 if (res && (res != 10)) /* XXX what for ? */
  68                         ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
  69                 return NULL;
  70         }
  71         *whennext = s->fr.samples;
  72         return &s->fr;
  73 }
  74
  75 static int g729_write(struct ast_filestream *fs, struct ast_frame *f)
  76 {
  77         int res;
  78         if (f->frametype != AST_FRAME_VOICE) {
  79                 ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
  80                 return -1;
  81         }
  82         if (f->subclass != AST_FORMAT_G729A) {
  83                 ast_log(LOG_WARNING, "Asked to write non-G729 frame (%d)!\n", f->subclass);
  84                 return -1;
  85         }
  86         if (f->datalen % 10) {
  87                 ast_log(LOG_WARNING, "Invalid data length, %d, should be multiple of 10\n", f->datalen);
  88                 return -1;
  89         }
  90         if ((res = fwrite(f->data, 1, f->datalen, fs->f)) != f->datalen) {
  91                         ast_log(LOG_WARNING, "Bad write (%d/10): %s\n", res, strerror(errno));
  92                         return -1;
  93         }
  94         return 0;
  95 }
  96
  97 static int g729_seek(struct ast_filestream *fs, off_t sample_offset, int whence)
  98 {
  99         long bytes;
 100         off_t min,cur,max,offset=0;
 101         min = 0;
 102         cur = ftello(fs->f);
 103         fseeko(fs->f, 0, SEEK_END);
 104         max = ftello(fs->f);
 105
 106         bytes = BUF_SIZE * (sample_offset / G729A_SAMPLES);
 107         if (whence == SEEK_SET)
 108                 offset = bytes;
 109         else if (whence == SEEK_CUR || whence == SEEK_FORCECUR)
 110                 offset = cur + bytes;
 111         else if (whence == SEEK_END)
 112                 offset = max - bytes;
 113         if (whence != SEEK_FORCECUR) {
 114                 offset = (offset > max)?max:offset;
 115         }
 116         /* protect against seeking beyond begining. */
 117         offset = (offset < min)?min:offset;
 118         if (fseeko(fs->f, offset, SEEK_SET) < 0)
 119                 return -1;
 120         return 0;
 121 }
 122
 123 static int g729_trunc(struct ast_filestream *fs)
 124 {
 125         /* Truncate file to current length */
 126         if (ftruncate(fileno(fs->f), ftello(fs->f)) < 0)
 127                 return -1;
 128         return 0;
 129 }
 130
 131 static off_t g729_tell(struct ast_filestream *fs)
 132 {
 133         off_t offset = ftello(fs->f);
 134         return (offset/BUF_SIZE)*G729A_SAMPLES;
 135 }
 136
 137 static const struct ast_format g729_f = {
 138         .name = "g729",
 139         .exts = "g729",
 140         .format = AST_FORMAT_G729A,
 141         .write = g729_write,
 142         .seek = g729_seek,
 143         .trunc = g729_trunc,
 144         .tell = g729_tell,
 145         .read = g729_read,
 146         .buf_size = BUF_SIZE + AST_FRIENDLY_OFFSET,
 147 };
 148
 149 static int load_module(void)
 150 {
 151         return ast_format_register(&g729_f);
 152 }
 153
 154 static int unload_module(void)
 155 {
 156         return ast_format_unregister(g729_f.name);
 157 }
 158
 159 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Raw G729 data");