Fri Aug 17 00:17:40 2018

Asterisk developer's documentation


format_g729.c File Reference

Save to raw, headerless G729 data. More...

#include "asterisk.h"
#include "asterisk/mod_format.h"
#include "asterisk/module.h"
#include "asterisk/endian.h"

Go to the source code of this file.

Defines

#define BUF_SIZE   20
#define G729A_SAMPLES   160

Functions

 AST_MODULE_INFO (ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER,"Raw G.729 data",.load=load_module,.unload=unload_module,.load_pri=AST_MODPRI_APP_DEPEND)
static struct ast_frameg729_read (struct ast_filestream *s, int *whennext)
static int g729_seek (struct ast_filestream *fs, off_t sample_offset, int whence)
static off_t g729_tell (struct ast_filestream *fs)
static int g729_trunc (struct ast_filestream *fs)
static int g729_write (struct ast_filestream *fs, struct ast_frame *f)
static int load_module (void)
static int unload_module (void)

Variables

static struct ast_format g729_f

Detailed Description

Save to raw, headerless G729 data.

Note:
This is not an encoder/decoder. The codec fo g729 is only available with a commercial license from Digium, due to patent restrictions. Check http://www.digium.com for information.
  • Extensions: g729

Definition in file format_g729.c.


Define Documentation

#define BUF_SIZE   20

Definition at line 45 of file format_g729.c.

#define G729A_SAMPLES   160

Definition at line 46 of file format_g729.c.

Referenced by g729_read(), g729_seek(), and g729_tell().


Function Documentation

AST_MODULE_INFO ( ASTERISK_GPL_KEY  ,
AST_MODFLAG_LOAD_ORDER  ,
"Raw G.729 data"  ,
load = load_module,
unload = unload_module,
load_pri = AST_MODPRI_APP_DEPEND 
)
static struct ast_frame* g729_read ( struct ast_filestream s,
int *  whennext 
) [static, read]

Definition at line 48 of file format_g729.c.

References AST_FORMAT_G729A, AST_FRAME_SET_BUFFER, AST_FRAME_VOICE, AST_FRIENDLY_OFFSET, ast_log(), ast_filestream::buf, BUF_SIZE, ast_frame_subclass::codec, ast_frame::data, ast_frame::datalen, errno, ast_filestream::f, ast_filestream::fr, ast_frame::frametype, G729A_SAMPLES, LOG_WARNING, ast_frame::mallocd, ast_frame::ptr, ast_frame::samples, and ast_frame::subclass.

00049 {
00050    int res;
00051    /* Send a frame from the file to the appropriate channel */
00052    s->fr.frametype = AST_FRAME_VOICE;
00053    s->fr.subclass.codec = AST_FORMAT_G729A;
00054    s->fr.mallocd = 0;
00055    s->fr.samples = G729A_SAMPLES;
00056    AST_FRAME_SET_BUFFER(&s->fr, s->buf, AST_FRIENDLY_OFFSET, BUF_SIZE);
00057    if ((res = fread(s->fr.data.ptr, 1, s->fr.datalen, s->f)) != s->fr.datalen) {
00058       if (res && (res != 10)) /* XXX what for ? */
00059          ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
00060       return NULL;
00061    }
00062    *whennext = s->fr.samples;
00063    return &s->fr;
00064 }

static int g729_seek ( struct ast_filestream fs,
off_t  sample_offset,
int  whence 
) [static]

Definition at line 88 of file format_g729.c.

References BUF_SIZE, ast_filestream::f, G729A_SAMPLES, ast_frame::offset, and SEEK_FORCECUR.

00089 {
00090    long bytes;
00091    off_t min,cur,max,offset=0;
00092    min = 0;
00093    cur = ftello(fs->f);
00094    fseeko(fs->f, 0, SEEK_END);
00095    max = ftello(fs->f);
00096    
00097    bytes = BUF_SIZE * (sample_offset / G729A_SAMPLES);
00098    if (whence == SEEK_SET)
00099       offset = bytes;
00100    else if (whence == SEEK_CUR || whence == SEEK_FORCECUR)
00101       offset = cur + bytes;
00102    else if (whence == SEEK_END)
00103       offset = max - bytes;
00104    if (whence != SEEK_FORCECUR) {
00105       offset = (offset > max)?max:offset;
00106    }
00107    /* protect against seeking beyond begining. */
00108    offset = (offset < min)?min:offset;
00109    if (fseeko(fs->f, offset, SEEK_SET) < 0)
00110       return -1;
00111    return 0;
00112 }

static off_t g729_tell ( struct ast_filestream fs  )  [static]

Definition at line 131 of file format_g729.c.

References BUF_SIZE, ast_filestream::f, G729A_SAMPLES, and ast_frame::offset.

00132 {
00133    off_t offset = ftello(fs->f);
00134    return (offset/BUF_SIZE)*G729A_SAMPLES;
00135 }

static int g729_trunc ( struct ast_filestream fs  )  [static]

Definition at line 114 of file format_g729.c.

References ast_log(), AST_LOG_WARNING, errno, and ast_filestream::f.

00115 {
00116    int fd;
00117    off_t cur;
00118 
00119    if ((fd = fileno(fs->f)) < 0) {
00120       ast_log(AST_LOG_WARNING, "Unable to determine file descriptor for g729 filestream %p: %s\n", fs, strerror(errno));
00121       return -1;
00122    }
00123    if ((cur = ftello(fs->f)) < 0) {
00124       ast_log(AST_LOG_WARNING, "Unable to determine current position in g729 filestream %p: %s\n", fs, strerror(errno));
00125       return -1;
00126    }
00127    /* Truncate file to current length */
00128    return ftruncate(fd, cur);
00129 }

static int g729_write ( struct ast_filestream fs,
struct ast_frame f 
) [static]

Definition at line 66 of file format_g729.c.

References AST_FORMAT_G729A, AST_FRAME_VOICE, ast_getformatname(), ast_log(), ast_frame_subclass::codec, ast_frame::data, ast_frame::datalen, errno, ast_filestream::f, ast_frame::frametype, LOG_WARNING, ast_frame::ptr, and ast_frame::subclass.

00067 {
00068    int res;
00069    if (f->frametype != AST_FRAME_VOICE) {
00070       ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
00071       return -1;
00072    }
00073    if (f->subclass.codec != AST_FORMAT_G729A) {
00074       ast_log(LOG_WARNING, "Asked to write non-G729 frame (%s)!\n", ast_getformatname(f->subclass.codec));
00075       return -1;
00076    }
00077    if (f->datalen % 10) {
00078       ast_log(LOG_WARNING, "Invalid data length, %d, should be multiple of 10\n", f->datalen);
00079       return -1;
00080    }
00081    if ((res = fwrite(f->data.ptr, 1, f->datalen, fs->f)) != f->datalen) {
00082          ast_log(LOG_WARNING, "Bad write (%d/10): %s\n", res, strerror(errno));
00083          return -1;
00084    }
00085    return 0;
00086 }

static int load_module ( void   )  [static]

Definition at line 149 of file format_g729.c.

References ast_format_register, AST_MODULE_LOAD_FAILURE, and AST_MODULE_LOAD_SUCCESS.

00150 {
00151    if (ast_format_register(&g729_f))
00152       return AST_MODULE_LOAD_FAILURE;
00153    return AST_MODULE_LOAD_SUCCESS;
00154 }

static int unload_module ( void   )  [static]

Definition at line 156 of file format_g729.c.

References ast_format_unregister(), and ast_format::name.

00157 {
00158    return ast_format_unregister(g729_f.name);
00159 }


Variable Documentation

struct ast_format g729_f [static]

Definition at line 137 of file format_g729.c.


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