asterisk/formats/format_ilbc.c

157 lines
4.0 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Brian K. West <brian@bkw.org>
*
* Copyright (C) 1999 - 2005, Digium, Inc.
*
* Mark Spencer <markster@digium.com>
*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2. See the LICENSE file
* at the top of the source tree.
*/
/*! \file
*
* \brief Save to raw, headerless iLBC data.
* \arg File name extension: ilbc
* \ingroup formats
*/
/*** MODULEINFO
<support_level>core</support_level>
***/
#include "asterisk.h"
#include "asterisk/mod_format.h"
#include "asterisk/module.h"
#include "asterisk/endian.h"
#include "asterisk/format_cache.h"
/* Some Ideas for this code came from makeg729e.c by Jeffrey Chilton */
/* Portions of the conversion code are by guido@sienanet.it */
#define ILBC_BUF_SIZE 50 /* One Real iLBC Frame */
#define ILBC_SAMPLES 240
static struct ast_frame *ilbc_read(struct ast_filestream *s, int *whennext)
{
size_t res;
/* Send a frame from the file to the appropriate channel */
AST_FRAME_SET_BUFFER(&s->fr, s->buf, AST_FRIENDLY_OFFSET, ILBC_BUF_SIZE);
if ((res = fread(s->fr.data.ptr, 1, s->fr.datalen, s->f)) != s->fr.datalen) {
if (res) {
ast_log(LOG_WARNING, "Short read of %s data (expected %d bytes, read %zu): %s\n",
ast_format_get_name(s->fr.subclass.format), s->fr.datalen, res,
strerror(errno));
}
return NULL;
}
*whennext = s->fr.samples = ILBC_SAMPLES;
return &s->fr;
}
static int ilbc_write(struct ast_filestream *fs, struct ast_frame *f)
{
int res;
if (f->datalen % 50) {
ast_log(LOG_WARNING, "Invalid data length, %d, should be multiple of 50\n", f->datalen);
return -1;
}
if ((res = fwrite(f->data.ptr, 1, f->datalen, fs->f)) != f->datalen) {
ast_log(LOG_WARNING, "Bad write (%d/50): %s\n", res, strerror(errno));
return -1;
}
return 0;
}
static int ilbc_seek(struct ast_filestream *fs, off_t sample_offset, int whence)
{
long bytes;
off_t min,cur,max,offset=0;
min = 0;
cur = ftello(fs->f);
fseeko(fs->f, 0, SEEK_END);
max = ftello(fs->f);
bytes = ILBC_BUF_SIZE * (sample_offset / ILBC_SAMPLES);
if (whence == SEEK_SET)
offset = bytes;
else if (whence == SEEK_CUR || whence == SEEK_FORCECUR)
offset = cur + bytes;
else if (whence == SEEK_END)
offset = max - bytes;
if (whence != SEEK_FORCECUR) {
offset = (offset > max)?max:offset;
}
/* protect against seeking beyond begining. */
offset = (offset < min)?min:offset;
if (fseeko(fs->f, offset, SEEK_SET) < 0)
return -1;
return 0;
}
static int ilbc_trunc(struct ast_filestream *fs)
{
int fd;
off_t cur;
if ((fd = fileno(fs->f)) < 0) {
ast_log(AST_LOG_WARNING, "Unable to determine file descriptor for iLBC filestream %p: %s\n", fs, strerror(errno));
return -1;
}
if ((cur = ftello(fs->f)) < 0) {
ast_log(AST_LOG_WARNING, "Unable to determine current position in iLBC filestream %p: %s\n", fs, strerror(errno));
return -1;
}
/* Truncate file to current length */
return ftruncate(fd, cur);
}
static off_t ilbc_tell(struct ast_filestream *fs)
{
off_t offset = ftello(fs->f);
return (offset/ILBC_BUF_SIZE)*ILBC_SAMPLES;
}
static struct ast_format_def ilbc_f = {
.name = "iLBC",
.exts = "ilbc",
.write = ilbc_write,
.seek = ilbc_seek,
.trunc = ilbc_trunc,
.tell = ilbc_tell,
.read = ilbc_read,
.buf_size = ILBC_BUF_SIZE + AST_FRIENDLY_OFFSET,
};
static int load_module(void)
{
ilbc_f.format = ast_format_ilbc;
if (ast_format_def_register(&ilbc_f))
return AST_MODULE_LOAD_DECLINE;
return AST_MODULE_LOAD_SUCCESS;
}
static int unload_module(void)
{
return ast_format_def_unregister(ilbc_f.name);
}
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "Raw iLBC data",
.support_level = AST_MODULE_SUPPORT_CORE,
.load = load_module,
.unload = unload_module,
.load_pri = AST_MODPRI_APP_DEPEND
);