Wed Oct 28 11:52:27 2009

Asterisk developer's documentation


format_sln.c File Reference

RAW SLINEAR Format. More...

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

Include dependency graph for format_sln.c:

Go to the source code of this file.

Defines

#define BUF_SIZE   320
#define SLIN_SAMPLES   160

Functions

static void __reg_module (void)
static void __unreg_module (void)
static int load_module (void)
static struct ast_frameslinear_read (struct ast_filestream *s, int *whennext)
static int slinear_seek (struct ast_filestream *fs, off_t sample_offset, int whence)
static off_t slinear_tell (struct ast_filestream *fs)
static int slinear_trunc (struct ast_filestream *fs)
static int slinear_write (struct ast_filestream *fs, struct ast_frame *f)
static int unload_module (void)

Variables

static struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_DEFAULT , .description = "Raw Signed Linear Audio support (SLN)" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, }
static struct ast_module_infoast_module_info = &__mod_info
static struct ast_format slin_f


Detailed Description

RAW SLINEAR Format.

Definition in file format_sln.c.


Define Documentation

#define BUF_SIZE   320

Definition at line 33 of file format_sln.c.

#define SLIN_SAMPLES   160

Definition at line 34 of file format_sln.c.


Function Documentation

static void __reg_module ( void   )  [static]

Definition at line 130 of file format_sln.c.

static void __unreg_module ( void   )  [static]

Definition at line 130 of file format_sln.c.

static int load_module ( void   )  [static]

Definition at line 118 of file format_sln.c.

References ast_format_register, AST_MODULE_LOAD_FAILURE, and AST_MODULE_LOAD_SUCCESS.

00119 {
00120    if (ast_format_register(&slin_f))
00121       return AST_MODULE_LOAD_FAILURE;
00122    return AST_MODULE_LOAD_SUCCESS;
00123 }

static struct ast_frame* slinear_read ( struct ast_filestream s,
int *  whennext 
) [static, read]

Definition at line 36 of file format_sln.c.

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

00037 {
00038    int res;
00039    /* Send a frame from the file to the appropriate channel */
00040 
00041    s->fr.frametype = AST_FRAME_VOICE;
00042    s->fr.subclass = AST_FORMAT_SLINEAR;
00043    s->fr.mallocd = 0;
00044    AST_FRAME_SET_BUFFER(&s->fr, s->buf, AST_FRIENDLY_OFFSET, BUF_SIZE);
00045    if ((res = fread(s->fr.data.ptr, 1, s->fr.datalen, s->f)) < 1) {
00046       if (res)
00047          ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
00048       return NULL;
00049    }
00050    *whennext = s->fr.samples = res/2;
00051    s->fr.datalen = res;
00052    return &s->fr;
00053 }

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

Definition at line 73 of file format_sln.c.

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

00074 {
00075    off_t offset=0,min,cur,max;
00076 
00077    min = 0;
00078    sample_offset <<= 1;
00079    cur = ftello(fs->f);
00080    fseeko(fs->f, 0, SEEK_END);
00081    max = ftello(fs->f);
00082    if (whence == SEEK_SET)
00083       offset = sample_offset;
00084    else if (whence == SEEK_CUR || whence == SEEK_FORCECUR)
00085       offset = sample_offset + cur;
00086    else if (whence == SEEK_END)
00087       offset = max - sample_offset;
00088    if (whence != SEEK_FORCECUR) {
00089       offset = (offset > max)?max:offset;
00090    }
00091    /* always protect against seeking past begining. */
00092    offset = (offset < min)?min:offset;
00093    return fseeko(fs->f, offset, SEEK_SET);
00094 }

static off_t slinear_tell ( struct ast_filestream fs  )  [static]

Definition at line 101 of file format_sln.c.

References ast_filestream::f.

00102 {
00103    return ftello(fs->f) / 2;
00104 }

static int slinear_trunc ( struct ast_filestream fs  )  [static]

Definition at line 96 of file format_sln.c.

References ast_filestream::f.

00097 {
00098    return ftruncate(fileno(fs->f), ftello(fs->f));
00099 }

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

Definition at line 55 of file format_sln.c.

References AST_FORMAT_SLINEAR, AST_FRAME_VOICE, ast_log(), ast_frame::data, ast_frame::datalen, errno, ast_filestream::f, ast_frame::frametype, LOG_WARNING, ast_frame::ptr, and ast_frame::subclass.

00056 {
00057    int res;
00058    if (f->frametype != AST_FRAME_VOICE) {
00059       ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
00060       return -1;
00061    }
00062    if (f->subclass != AST_FORMAT_SLINEAR) {
00063       ast_log(LOG_WARNING, "Asked to write non-slinear frame (%d)!\n", f->subclass);
00064       return -1;
00065    }
00066    if ((res = fwrite(f->data.ptr, 1, f->datalen, fs->f)) != f->datalen) {
00067          ast_log(LOG_WARNING, "Bad write (%d/%d): %s\n", res, f->datalen, strerror(errno));
00068          return -1;
00069    }
00070    return 0;
00071 }

static int unload_module ( void   )  [static]

Definition at line 125 of file format_sln.c.

References ast_format_unregister(), and ast_format::name.

00126 {
00127    return ast_format_unregister(slin_f.name);
00128 }  


Variable Documentation

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_DEFAULT , .description = "Raw Signed Linear Audio support (SLN)" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, } [static]

Definition at line 130 of file format_sln.c.

Definition at line 130 of file format_sln.c.

struct ast_format slin_f [static]

Definition at line 106 of file format_sln.c.


Generated on Wed Oct 28 11:52:27 2009 for Asterisk - the Open Source PBX by  doxygen 1.5.6