app_audiosocket.c File Reference

AudioSocket application – transmit and receive audio through a TCP socket. More...

#include "asterisk.h"
#include "errno.h"
#include <uuid/uuid.h>
#include "asterisk/file.h"
#include "asterisk/module.h"
#include "asterisk/channel.h"
#include "asterisk/app.h"
#include "asterisk/pbx.h"
#include "asterisk/res_audiosocket.h"
#include "asterisk/utils.h"
#include "asterisk/format_cache.h"

Include dependency graph for app_audiosocket.c:

Go to the source code of this file.

Macros
#define	AST_MODULE   "app_audiosocket"
#define	AUDIOSOCKET_CONFIG   "audiosocket.conf"
#define	MAX_WAIT_TIMEOUT_MSEC   2000

Functions
static void	__reg_module (void)
static void	__unreg_module (void)
struct ast_module *	AST_MODULE_SELF_SYM (void)
static int	audiosocket_exec (struct ast_channel *chan, const char *data)
static int	audiosocket_run (struct ast_channel *chan, const char *id, const int svc, const char *server)
static int	load_module (void)
static int	unload_module (void)

Variables
static struct ast_module_info	__mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "AudioSocket Application" , .key = ASTERISK_GPL_KEY , .buildopt_sum = AST_BUILDOPT_SUM, .support_level = AST_MODULE_SUPPORT_EXTENDED, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_CHANNEL_DRIVER, .requires = "res_audiosocket", }
static const char	app [] = "AudioSocket"
static const struct ast_module_info *	ast_module_info = &__mod_info

Detailed Description

AudioSocket application – transmit and receive audio through a TCP socket.

Author

Seán C McCord scm@c.nosp@m.ycor.nosp@m.esys..nosp@m.com

Definition in file app_audiosocket.c.

Macro Definition Documentation

AST_MODULE

#define AST_MODULE   "app_audiosocket"

Definition at line 46 of file app_audiosocket.c.

AUDIOSOCKET_CONFIG

#define AUDIOSOCKET_CONFIG   "audiosocket.conf"

Definition at line 47 of file app_audiosocket.c.

MAX_WAIT_TIMEOUT_MSEC

#define MAX_WAIT_TIMEOUT_MSEC   2000

Definition at line 48 of file app_audiosocket.c.

Function Documentation

__reg_module()

static void __reg_module ( void  )

static

Definition at line 247 of file app_audiosocket.c.

__unreg_module()

static void __unreg_module ( void  )

static

Definition at line 247 of file app_audiosocket.c.

AST_MODULE_SELF_SYM()

struct ast_module * AST_MODULE_SELF_SYM

(

void

)

Definition at line 247 of file app_audiosocket.c.

audiosocket_exec()

static int audiosocket_exec ( struct ast_channel *  chan, const char *  data  )

static

Definition at line 78 of file app_audiosocket.c.

{
    char *parse;
    struct ast_format *readFormat, *writeFormat;
    const char *chanName;
    int res;
 
    AST_DECLARE_APP_ARGS(args,
        AST_APP_ARG(idStr);
        AST_APP_ARG(server);
    );
 
    int s = 0;
    uuid_t uu;
 
 
    chanName = ast_channel_name(chan);
 
    /* Parse and validate arguments */
    parse = ast_strdupa(data);
    AST_STANDARD_APP_ARGS(args, parse);
    if (ast_strlen_zero(args.idStr)) {
        ast_log(LOG_ERROR, "UUID is required\n");
        return -1;
    }
    if (uuid_parse(args.idStr, uu)) {
        ast_log(LOG_ERROR, "Failed to parse UUID '%s'\n", args.idStr);
        return -1;
    }
    if ((s = ast_audiosocket_connect(args.server, chan)) < 0) {
        /* The res module will already output a log message, so another is not needed */
        return -1;
    }
 
    /* Save current channel audio format and force to linear PCM. */
 
    writeFormat = ao2_bump(ast_channel_writeformat(chan));
    readFormat = ao2_bump(ast_channel_readformat(chan));
 
    if (ast_set_write_format(chan, ast_format_slin)) {
        ast_log(LOG_ERROR, "Failed to set write format to SLINEAR for channel '%s'\n", chanName);
        res = -1;
        goto end;
    }
 
    if (ast_set_read_format(chan, ast_format_slin)) {
        ast_log(LOG_ERROR, "Failed to set read format to SLINEAR for channel '%s'\n", chanName);
        res = -1;
        goto end;
    }
 
    /* Only a requested hangup or socket closure from the remote end will
       return a 0 value (normal exit). All other events that disrupt an
       active connection are treated as errors for now (non-zero). */
 
    res = audiosocket_run(chan, args.idStr, s, args.server);
 
end:
 
    /* Restore previous formats and close the connection */
    if (ast_set_write_format(chan, writeFormat)) {
        ast_log(LOG_ERROR, "Failed to restore write format for channel '%s'\n", chanName);
    }
    if (ast_set_read_format(chan, readFormat)) {
        ast_log(LOG_ERROR, "Failed to restore read format for channel '%s'\n", chanName);
    }
    ao2_ref(writeFormat, -1);
    ao2_ref(readFormat, -1);
    close(s);
 
    return res;
}

References ao2_bump, ao2_ref, args, AST_APP_ARG, ast_audiosocket_connect(), ast_channel_name(), ast_channel_readformat(), ast_channel_writeformat(), AST_DECLARE_APP_ARGS, ast_format_slin, ast_log, ast_set_read_format(), ast_set_write_format(), AST_STANDARD_APP_ARGS, ast_strdupa, ast_strlen_zero(), audiosocket_run(), end, and LOG_ERROR.

Referenced by load_module().

audiosocket_run()

static int audiosocket_run ( struct ast_channel *  chan, const char *  id, const int  svc, const char *  server  )

static

Definition at line 151 of file app_audiosocket.c.

{
    const char *chanName;
    struct ast_channel *targetChan;
    int ms = MAX_WAIT_TIMEOUT_MSEC;
    int outfd = -1;
    struct ast_frame *f;
    int hangup;
 
    if (!chan || ast_channel_state(chan) != AST_STATE_UP) {
        ast_log(LOG_ERROR, "Channel is %s\n", chan ? "not answered" : "missing");
        return -1;
    }
 
    if (ast_audiosocket_init(svc, id)) {
        ast_log(LOG_ERROR, "Failed to initialize AudioSocket\n");
        return -1;
    }
 
    chanName = ast_channel_name(chan);
 
    while (1) {
        /* Timeout is hard-coded currently, could be made into an
           argument if needed, but 2 seconds seems like a realistic
           time range to give. */
        targetChan = ast_waitfor_nandfds(&chan, 1, &svc, 1, NULL, &outfd, &ms);
        ms = MAX_WAIT_TIMEOUT_MSEC;
 
        if (targetChan) {
            /* Receive frame from connected channel. */
            f = ast_read(chan);
            if (!f) {
                ast_log(LOG_WARNING, "Failed to receive frame from channel '%s' connected to AudioSocket server '%s'", chanName, server);
                return -1;
            }
 
            if (f->frametype == AST_FRAME_VOICE || f->frametype == AST_FRAME_DTMF) {
                /* Send audio frame or DTMF frame to audiosocket */
                if (ast_audiosocket_send_frame(svc, f)) {
                    ast_log(LOG_WARNING, "Failed to forward frame from channel '%s' to AudioSocket server '%s'\n",
                        chanName, server);
                    ast_frfree(f);
                    return -1;
                }
            }
            ast_frfree(f);
 
        } else if (outfd >= 0) {
            /* Receive audio frame from audiosocket. */
            f = ast_audiosocket_receive_frame_with_hangup(svc, &hangup);
            if (hangup) {
                /* Graceful termination, no frame to free. */
                return 0;
            }
            if (!f) {
                ast_log(LOG_WARNING, "Failed to receive frame from AudioSocket server '%s'"
                    " connected to channel '%s'\n", server, chanName);
                return -1;
            }
            /* Send audio frame to connected channel. */
            if (ast_write(chan, f)) {
                ast_log(LOG_WARNING, "Failed to forward frame from AudioSocket server '%s' to channel '%s'\n", server, chanName);
                ast_frfree(f);
                return -1;
            }
            ast_frfree(f);
 
        } else {
            /* Neither the channel nor audio socket had activity
               before timeout. Assume connection was lost. */
            ast_log(LOG_ERROR, "Reached timeout after %d ms of no activity on AudioSocket connection between '%s' and '%s'\n", MAX_WAIT_TIMEOUT_MSEC, chanName, server);
            return -1;
        }
    }
    return 0;
}

References ast_audiosocket_init(), ast_audiosocket_receive_frame_with_hangup(), ast_audiosocket_send_frame(), ast_channel_name(), AST_FRAME_DTMF, AST_FRAME_VOICE, ast_frfree, ast_log, ast_read(), AST_STATE_UP, ast_waitfor_nandfds(), ast_write(), ast_frame::frametype, hangup(), LOG_ERROR, LOG_WARNING, MAX_WAIT_TIMEOUT_MSEC, and NULL.

Referenced by audiosocket_exec().

load_module()

static int load_module ( void  )

static

Definition at line 233 of file app_audiosocket.c.

{
    return ast_register_application_xml(app, audiosocket_exec);
}

References app, ast_register_application_xml, and audiosocket_exec().

unload_module()

static int unload_module ( void  )

static

Definition at line 228 of file app_audiosocket.c.

{
    return ast_unregister_application(app);
}

References app, and ast_unregister_application().

Variable Documentation

__mod_info

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "AudioSocket Application" , .key = ASTERISK_GPL_KEY , .buildopt_sum = AST_BUILDOPT_SUM, .support_level = AST_MODULE_SUPPORT_EXTENDED, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_CHANNEL_DRIVER, .requires = "res_audiosocket", }

static

Definition at line 247 of file app_audiosocket.c.

app

const char app[] = "AudioSocket"

static

Definition at line 74 of file app_audiosocket.c.

Referenced by load_module(), and unload_module().

ast_module_info

const struct ast_module_info* ast_module_info = &__mod_info

static

Definition at line 247 of file app_audiosocket.c.