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"

Include dependency graph for func_volume.c:

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)
struct ast_module *	AST_MODULE_SELF_SYM (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_read (struct ast_channel *chan, const char *cmd, char *data, char *buffer, size_t buflen)
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 = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, .support_level = AST_MODULE_SUPPORT_CORE, }
static const struct ast_module_info *	ast_module_info = &__mod_info
static const struct ast_datastore_info	volume_datastore
	Static structure for datastore information. More...
static struct ast_custom_function	volume_function
static const struct ast_app_option	volume_opts [128] = { [ 'p' ] = { .flag = VOLUMEFLAG_CHANGE }, }

Detailed Description

Technology independent volume control.

Author

Joshua Colp jcolp.nosp@m.@dig.nosp@m.ium.c.nosp@m.om

Definition in file func_volume.c.

Enumeration Type Documentation

volume_flags

enum volume_flags

Enumerator
VOLUMEFLAG_CHANGE

Definition at line 91 of file func_volume.c.

                  {
    VOLUMEFLAG_CHANGE = (1 << 1),
};

Function Documentation

__reg_module()

static void __reg_module ( void  )

static

Definition at line 298 of file func_volume.c.

__unreg_module()

static void __unreg_module ( void  )

static

Definition at line 298 of file func_volume.c.

AST_MODULE_SELF_SYM()

struct ast_module * AST_MODULE_SELF_SYM

(

void

)

Definition at line 298 of file func_volume.c.

destroy_callback()

static void destroy_callback ( void *  data )

static

Definition at line 99 of file func_volume.c.

{
    struct volume_information *vi = data;
 
    /* Destroy the audiohook, and destroy ourselves */
    ast_audiohook_lock(&vi->audiohook);
    ast_audiohook_detach(&vi->audiohook);
    ast_audiohook_unlock(&vi->audiohook);
    ast_audiohook_destroy(&vi->audiohook);
    ast_free(vi);
 
    return;
}

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

load_module()

static int load_module ( void  )

static

Definition at line 293 of file func_volume.c.

{
    return ast_custom_function_register(&volume_function);
}

References ast_custom_function_register, and volume_function.

unload_module()

static int unload_module ( void  )

static

Definition at line 288 of file func_volume.c.

{
    return ast_custom_function_unregister(&volume_function);
}

References ast_custom_function_unregister(), and volume_function.

volume_callback()

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 119 of file func_volume.c.

{
    struct ast_datastore *datastore = NULL;
    struct volume_information *vi = NULL;
    float *gain = NULL;
 
    /* If the audiohook is stopping it means the channel is shutting down.... but we let the datastore destroy take care of it */
    if (audiohook->status == AST_AUDIOHOOK_STATUS_DONE)
        return 0;
 
    /* Grab datastore which contains our gain information */
    if (!(datastore = ast_channel_datastore_find(chan, &volume_datastore, NULL)))
        return 0;
 
    vi = datastore->data;
 
    /* If this is DTMF then allow them to increase/decrease the gains */
    if (ast_test_flag(vi, VOLUMEFLAG_CHANGE)) {
        if (frame->frametype == AST_FRAME_DTMF) {
            /* Only use DTMF coming from the source... not going to it */
            if (direction != AST_AUDIOHOOK_DIRECTION_READ)
                return 0;
            if (frame->subclass.integer == '*') {
                vi->tx_gain += 1;
                vi->rx_gain += 1;
            } else if (frame->subclass.integer == '#') {
                vi->tx_gain -= 1;
                vi->rx_gain -= 1;
            }
        }
    }
 
 
    if (frame->frametype == AST_FRAME_VOICE) {
        /* Based on direction of frame grab the gain, and confirm it is applicable */
        if (!(gain = (direction == AST_AUDIOHOOK_DIRECTION_READ) ? &vi->rx_gain : &vi->tx_gain) || !*gain)
            return 0;
        /* Apply gain to frame... easy as pi */
        ast_frame_adjust_volume_float(frame, *gain);
    }
 
    return 0;
}

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

Referenced by volume_write().

volume_read()

static int volume_read ( struct ast_channel *  chan, const char *  cmd, char *  data, char *  buffer, size_t  buflen  )

static

Definition at line 237 of file func_volume.c.

{
    struct ast_datastore *datastore = NULL;
    struct volume_information *vi = NULL;
 
    /* Separate options from argument */
 
    AST_DECLARE_APP_ARGS(args,
        AST_APP_ARG(direction);
        AST_APP_ARG(options);
    );
 
    if (!chan) {
        ast_log(LOG_WARNING, "No channel was provided to %s function.\n", cmd);
        return -1;
    }
 
    AST_STANDARD_APP_ARGS(args, data);
 
    ast_channel_lock(chan);
    if (!(datastore = ast_channel_datastore_find(chan, &volume_datastore, NULL))) {
        ast_channel_unlock(chan);
        return -1; /* no active audiohook, nothing to read */
    } else {
        ast_channel_unlock(chan);
        vi = datastore->data;
    }
 
    /* Obtain current gain using volume information structure */
    if (ast_strlen_zero(args.direction)) {
        ast_log(LOG_ERROR, "Direction must be specified for VOLUME function\n");
        return -1;
    }
 
    if (!strcasecmp(args.direction, "tx")) {
        snprintf(buffer, buflen, "%f", vi->tx_gain);
    } else if (!strcasecmp(args.direction, "rx")) {
        snprintf(buffer, buflen, "%f", vi->rx_gain);
    } else {
        ast_log(LOG_ERROR, "Direction must be either RX or TX\n");
    }
 
    return 0;
}

References args, AST_APP_ARG, ast_channel_datastore_find(), ast_channel_lock, ast_channel_unlock, AST_DECLARE_APP_ARGS, ast_log, AST_STANDARD_APP_ARGS, ast_strlen_zero(), ast_datastore::data, LOG_ERROR, LOG_WARNING, NULL, options, volume_information::rx_gain, volume_information::tx_gain, and volume_datastore.

volume_write()

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

static

Definition at line 163 of file func_volume.c.

{
    struct ast_datastore *datastore = NULL;
    struct volume_information *vi = NULL;
    int is_new = 0;
 
    /* Separate options from argument */
 
    AST_DECLARE_APP_ARGS(args,
        AST_APP_ARG(direction);
        AST_APP_ARG(options);
    );
 
    if (!chan) {
        ast_log(LOG_WARNING, "No channel was provided to %s function.\n", cmd);
        return -1;
    }
 
    AST_STANDARD_APP_ARGS(args, data);
 
    ast_channel_lock(chan);
    if (!(datastore = ast_channel_datastore_find(chan, &volume_datastore, NULL))) {
        ast_channel_unlock(chan);
        /* Allocate a new datastore to hold the reference to this volume and audiohook information */
        if (!(datastore = ast_datastore_alloc(&volume_datastore, NULL)))
            return 0;
        if (!(vi = ast_calloc(1, sizeof(*vi)))) {
            ast_datastore_free(datastore);
            return 0;
        }
        ast_audiohook_init(&vi->audiohook, AST_AUDIOHOOK_TYPE_MANIPULATE, "Volume", AST_AUDIOHOOK_MANIPULATE_ALL_RATES);
        vi->audiohook.manipulate_callback = volume_callback;
        ast_set_flag(&vi->audiohook, AST_AUDIOHOOK_WANTS_DTMF);
        is_new = 1;
    } else {
        ast_channel_unlock(chan);
        vi = datastore->data;
    }
 
    /* Adjust gain on volume information structure */
    if (ast_strlen_zero(args.direction)) {
        ast_log(LOG_ERROR, "Direction must be specified for VOLUME function\n");
        return -1;
    }
 
    if (!strcasecmp(args.direction, "tx")) {
        vi->tx_gain = atof(value);
    } else if (!strcasecmp(args.direction, "rx")) {
        vi->rx_gain = atof(value);
    } else {
        ast_log(LOG_ERROR, "Direction must be either RX or TX\n");
    }
 
    if (is_new) {
        datastore->data = vi;
        ast_channel_lock(chan);
        ast_channel_datastore_add(chan, datastore);
        ast_channel_unlock(chan);
        ast_audiohook_attach(chan, &vi->audiohook);
    }
 
    /* Add Option data to struct */
 
    if (!ast_strlen_zero(args.options)) {
        struct ast_flags flags = { 0 };
        ast_app_parse_options(volume_opts, &flags, NULL, args.options);
        vi->flags = flags.flags;
    } else {
        vi->flags = 0;
    }
 
    return 0;
}

References args, AST_APP_ARG, ast_app_parse_options(), ast_audiohook_attach(), ast_audiohook_init(), AST_AUDIOHOOK_MANIPULATE_ALL_RATES, 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, LOG_WARNING, ast_audiohook::manipulate_callback, NULL, options, volume_information::rx_gain, volume_information::tx_gain, value, volume_callback(), volume_datastore, and volume_opts.

Variable Documentation

__mod_info

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 = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, .support_level = AST_MODULE_SUPPORT_CORE, }

static

Definition at line 298 of file func_volume.c.

ast_module_info

const struct ast_module_info* ast_module_info = &__mod_info

static

Definition at line 298 of file func_volume.c.

volume_datastore

const struct ast_datastore_info volume_datastore

static

Initial value:

= {
    .type = "volume",
    .destroy = destroy_callback
}

Static structure for datastore information.

Definition at line 114 of file func_volume.c.

Referenced by volume_callback(), volume_read(), and volume_write().

volume_function

struct ast_custom_function volume_function

static

Initial value:

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

Definition at line 282 of file func_volume.c.

Referenced by load_module(), and unload_module().

volume_opts

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

static

Definition at line 97 of file func_volume.c.

Referenced by volume_write().