Mon Oct 8 12:39:23 2012

Asterisk developer's documentation


func_volume.c File Reference

Technology independent volume control. More...

#include "asterisk.h"
#include "asterisk/module.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/utils.h"
#include "asterisk/audiohook.h"
#include "asterisk/app.h"

Go to the source code of this file.

Data Structures

struct  volume_information

Enumerations

enum  volume_flags { VOLUMEFLAG_CHANGE = (1 << 1) }

Functions

static void __reg_module (void)
static void __unreg_module (void)
static void destroy_callback (void *data)
static int load_module (void)
static int unload_module (void)
static int volume_callback (struct ast_audiohook *audiohook, struct ast_channel *chan, struct ast_frame *frame, enum ast_audiohook_direction direction)
static int volume_write (struct ast_channel *chan, const char *cmd, char *data, const char *value)

Variables

static struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Technology independent volume control" , .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 = "ac1f6a56484a8820659555499174e588" , .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, }
static struct ast_module_infoast_module_info = &__mod_info
static struct ast_datastore_info volume_datastore
 Static structure for datastore information.
static struct ast_custom_function volume_function
static struct ast_app_option volume_opts [128] = { [ 'p' ] = { .flag = VOLUMEFLAG_CHANGE },}


Detailed Description

Technology independent volume control.

Author:
Joshua Colp <jcolp@digium.com>

Definition in file func_volume.c.


Enumeration Type Documentation

enum volume_flags

Enumerator:
VOLUMEFLAG_CHANGE 

Definition at line 80 of file func_volume.c.

00080                   {
00081    VOLUMEFLAG_CHANGE = (1 << 1),
00082 };


Function Documentation

static void __reg_module ( void   )  [static]

Definition at line 236 of file func_volume.c.

static void __unreg_module ( void   )  [static]

Definition at line 236 of file func_volume.c.

static void destroy_callback ( void *  data  )  [static]

Definition at line 88 of file func_volume.c.

References ast_audiohook_destroy(), ast_audiohook_detach(), ast_audiohook_lock, ast_audiohook_unlock, ast_free, and volume_information::audiohook.

00089 {
00090    struct volume_information *vi = data;
00091 
00092    /* Destroy the audiohook, and destroy ourselves */
00093    ast_audiohook_lock(&vi->audiohook);
00094    ast_audiohook_detach(&vi->audiohook);
00095    ast_audiohook_unlock(&vi->audiohook);
00096    ast_audiohook_destroy(&vi->audiohook);
00097    ast_free(vi);
00098 
00099    return;
00100 }

static int load_module ( void   )  [static]

Definition at line 231 of file func_volume.c.

References ast_custom_function_register, and volume_function.

00232 {
00233    return ast_custom_function_register(&volume_function);
00234 }

static int unload_module ( void   )  [static]

Definition at line 226 of file func_volume.c.

References ast_custom_function_unregister(), and volume_function.

00227 {
00228    return ast_custom_function_unregister(&volume_function);
00229 }

static int volume_callback ( struct ast_audiohook audiohook,
struct ast_channel chan,
struct ast_frame frame,
enum ast_audiohook_direction  direction 
) [static]

Definition at line 108 of file func_volume.c.

References AST_AUDIOHOOK_DIRECTION_READ, AST_AUDIOHOOK_STATUS_DONE, ast_channel_datastore_find(), ast_frame_adjust_volume(), AST_FRAME_DTMF, AST_FRAME_VOICE, ast_test_flag, volume_information::audiohook, ast_datastore::data, ast_frame::frametype, ast_frame_subclass::integer, volume_information::rx_gain, ast_audiohook::status, ast_frame::subclass, volume_information::tx_gain, volume_datastore, and VOLUMEFLAG_CHANGE.

Referenced by volume_write().

00109 {
00110    struct ast_datastore *datastore = NULL;
00111    struct volume_information *vi = NULL;
00112    int *gain = NULL;
00113 
00114    /* If the audiohook is stopping it means the channel is shutting down.... but we let the datastore destroy take care of it */
00115    if (audiohook->status == AST_AUDIOHOOK_STATUS_DONE)
00116       return 0;
00117 
00118    /* Grab datastore which contains our gain information */
00119    if (!(datastore = ast_channel_datastore_find(chan, &volume_datastore, NULL)))
00120       return 0;
00121 
00122    vi = datastore->data;
00123 
00124    /* If this is DTMF then allow them to increase/decrease the gains */
00125    if (ast_test_flag(vi, VOLUMEFLAG_CHANGE)) {
00126       if (frame->frametype == AST_FRAME_DTMF) {
00127          /* Only use DTMF coming from the source... not going to it */
00128          if (direction != AST_AUDIOHOOK_DIRECTION_READ)
00129             return 0; 
00130          if (frame->subclass.integer == '*') {
00131             vi->tx_gain += 1;
00132             vi->rx_gain += 1;
00133          } else if (frame->subclass.integer == '#') {
00134             vi->tx_gain -= 1;
00135             vi->rx_gain -= 1;
00136          }
00137       }
00138    }
00139 
00140    
00141    if (frame->frametype == AST_FRAME_VOICE) {
00142       /* Based on direction of frame grab the gain, and confirm it is applicable */
00143       if (!(gain = (direction == AST_AUDIOHOOK_DIRECTION_READ) ? &vi->rx_gain : &vi->tx_gain) || !*gain)
00144          return 0;
00145       /* Apply gain to frame... easy as pi */
00146       ast_frame_adjust_volume(frame, *gain);
00147    }
00148 
00149    return 0;
00150 }

static int volume_write ( struct ast_channel chan,
const char *  cmd,
char *  data,
const char *  value 
) [static]

Definition at line 152 of file func_volume.c.

References args, AST_APP_ARG, ast_app_parse_options(), ast_audiohook_attach(), ast_audiohook_init(), AST_AUDIOHOOK_TYPE_MANIPULATE, AST_AUDIOHOOK_WANTS_DTMF, ast_calloc, ast_channel_datastore_add(), ast_channel_datastore_find(), ast_channel_lock, ast_channel_unlock, ast_datastore_alloc, ast_datastore_free(), AST_DECLARE_APP_ARGS, ast_log(), ast_set_flag, AST_STANDARD_APP_ARGS, ast_strlen_zero(), volume_information::audiohook, ast_datastore::data, volume_information::flags, ast_flags::flags, LOG_ERROR, volume_information::rx_gain, volume_information::tx_gain, volume_callback(), volume_datastore, and volume_opts.

00153 {
00154    struct ast_datastore *datastore = NULL;
00155    struct volume_information *vi = NULL;
00156    int is_new = 0;
00157 
00158    /* Separate options from argument */
00159    
00160    AST_DECLARE_APP_ARGS(args,
00161       AST_APP_ARG(direction);
00162       AST_APP_ARG(options);
00163    );
00164    
00165    AST_STANDARD_APP_ARGS(args, data);
00166 
00167    ast_channel_lock(chan);
00168    if (!(datastore = ast_channel_datastore_find(chan, &volume_datastore, NULL))) {
00169       ast_channel_unlock(chan);
00170       /* Allocate a new datastore to hold the reference to this volume and audiohook information */
00171       if (!(datastore = ast_datastore_alloc(&volume_datastore, NULL)))
00172          return 0;
00173       if (!(vi = ast_calloc(1, sizeof(*vi)))) {
00174          ast_datastore_free(datastore);
00175          return 0;
00176       }
00177       ast_audiohook_init(&vi->audiohook, AST_AUDIOHOOK_TYPE_MANIPULATE, "Volume");
00178       vi->audiohook.manipulate_callback = volume_callback;
00179       ast_set_flag(&vi->audiohook, AST_AUDIOHOOK_WANTS_DTMF);
00180       is_new = 1;
00181    } else {
00182       ast_channel_unlock(chan);
00183       vi = datastore->data;
00184    }
00185 
00186    /* Adjust gain on volume information structure */
00187    if (ast_strlen_zero(args.direction)) {
00188       ast_log(LOG_ERROR, "Direction must be specified for VOLUME function\n");
00189       return -1;
00190    }
00191 
00192    if (!strcasecmp(args.direction, "tx")) { 
00193       vi->tx_gain = atoi(value); 
00194    } else if (!strcasecmp(args.direction, "rx")) {
00195       vi->rx_gain = atoi(value);
00196    } else {
00197       ast_log(LOG_ERROR, "Direction must be either RX or TX\n");
00198    }
00199 
00200    if (is_new) {
00201       datastore->data = vi;
00202       ast_channel_lock(chan);
00203       ast_channel_datastore_add(chan, datastore);
00204       ast_channel_unlock(chan);
00205       ast_audiohook_attach(chan, &vi->audiohook);
00206    }
00207 
00208    /* Add Option data to struct */
00209    
00210    if (!ast_strlen_zero(args.options)) {
00211       struct ast_flags flags = { 0 };
00212       ast_app_parse_options(volume_opts, &flags, NULL, args.options);
00213       vi->flags = flags.flags;
00214    } else { 
00215       vi->flags = 0; 
00216    }
00217 
00218    return 0;
00219 }


Variable Documentation

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Technology independent volume control" , .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 = "ac1f6a56484a8820659555499174e588" , .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, } [static]

Definition at line 236 of file func_volume.c.

struct ast_module_info* ast_module_info = &__mod_info [static]

Definition at line 236 of file func_volume.c.

struct ast_datastore_info volume_datastore [static]

Initial value:

 {
   .type = "volume",
   .destroy = destroy_callback
}
Static structure for datastore information.

Definition at line 103 of file func_volume.c.

Referenced by volume_callback(), and volume_write().

struct ast_custom_function volume_function [static]

Initial value:

 {
   .name = "VOLUME",
   .write = volume_write,
}

Definition at line 221 of file func_volume.c.

Referenced by load_module(), and unload_module().

struct ast_app_option volume_opts[128] = { [ 'p' ] = { .flag = VOLUMEFLAG_CHANGE },} [static]

Definition at line 86 of file func_volume.c.

Referenced by volume_write().


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