app_sf.c File Reference

SF sender and receiver applications. More...

#include "asterisk.h"
#include "asterisk/file.h"
#include "asterisk/pbx.h"
#include "asterisk/channel.h"
#include "asterisk/dsp.h"
#include "asterisk/app.h"
#include "asterisk/module.h"
#include "asterisk/indications.h"
#include "asterisk/conversions.h"

Include dependency graph for app_sf.c:

Go to the source code of this file.

Macros
#define	BUFFER_SIZE   256
#define	DEFAULT_POST_DIGIT_TIMER   0.8
#define	SF_BETWEEN   600
#define	SF_MIN_DETECT   50
#define	SF_MIN_OFF   25
#define	SF_ON   67

Enumerations
enum	{ OPT_ARG_DIGIT_TIMEOUT , OPT_ARG_ARRAY_SIZE }
enum	read_option_flags {   OPT_DELAY = (1 << 0) , OPT_MUTE = (1 << 1) , OPT_QUELCH = (1 << 2) , OPT_RELAXED = (1 << 3) ,   OPT_EXTRAPULSES = (1 << 4) , OPT_DIGIT_TIMEOUT = (1 << 5) }

Functions
	AST_MODULE_INFO_STANDARD_EXTENDED (ASTERISK_GPL_KEY, "SF Sender and Receiver Applications")
static int	load_module (void)
static int	read_sf_digits (struct ast_channel *chan, char *buf, int buflen, int timeout, int digit_timeout, int maxdigits, int freq, int features, int extrapulses)
	Detects SF digits on channel using DSP.
static int	read_sf_exec (struct ast_channel *chan, const char *data)
static int	sendsf_exec (struct ast_channel *chan, const char *vdata)
static int	unload_module (void)

Variables
static const struct ast_app_option	read_app_options [128] = { [ 'd' ] = { .flag = OPT_DELAY }, [ 'e' ] = { .flag = OPT_EXTRAPULSES }, [ 'm' ] = { .flag = OPT_MUTE }, [ 't' ] = { .flag = OPT_DIGIT_TIMEOUT , .arg_index = OPT_ARG_DIGIT_TIMEOUT + 1 }, [ 'q' ] = { .flag = OPT_QUELCH }, [ 'r' ] = { .flag = OPT_RELAXED }, }
static const char *	readsf_name = "ReceiveSF"
static const char	sendsf_name [] = "SendSF"

Detailed Description

SF sender and receiver applications.

Author

Naveen Albert aster.nosp@m.isk@.nosp@m.phrea.nosp@m.knet.nosp@m..org

Definition in file app_sf.c.

Macro Definition Documentation

BUFFER_SIZE

#define BUFFER_SIZE   256

DEFAULT_POST_DIGIT_TIMER

#define DEFAULT_POST_DIGIT_TIMER   0.8

Definition at line 164 of file app_sf.c.

SF_BETWEEN

#define SF_BETWEEN   600

Definition at line 169 of file app_sf.c.

SF_MIN_DETECT

#define SF_MIN_DETECT   50

Definition at line 170 of file app_sf.c.

SF_MIN_OFF

#define SF_MIN_OFF   25

Definition at line 167 of file app_sf.c.

SF_ON

#define SF_ON   67

Definition at line 168 of file app_sf.c.

Enumeration Type Documentation

anonymous enum

anonymous enum

Enumerator
OPT_ARG_DIGIT_TIMEOUT
OPT_ARG_ARRAY_SIZE

Definition at line 181 of file app_sf.c.

     {
    OPT_ARG_DIGIT_TIMEOUT,
    /* note: this entry _MUST_ be the last one in the enum */
    OPT_ARG_ARRAY_SIZE,
};

read_option_flags

enum read_option_flags

Enumerator
OPT_DELAY
OPT_MUTE
OPT_QUELCH
OPT_RELAXED
OPT_EXTRAPULSES
OPT_DIGIT_TIMEOUT

Definition at line 172 of file app_sf.c.

                       {
    OPT_DELAY = (1 << 0),
    OPT_MUTE = (1 << 1),
    OPT_QUELCH = (1 << 2),
    OPT_RELAXED = (1 << 3),
    OPT_EXTRAPULSES = (1 << 4),
    OPT_DIGIT_TIMEOUT = (1 << 5),
};

Function Documentation

AST_MODULE_INFO_STANDARD_EXTENDED()

AST_MODULE_INFO_STANDARD_EXTENDED	(	ASTERISK_GPL_KEY	,
		"SF Sender and Receiver Applications"
	)

load_module()

static int load_module ( void  )

static

Definition at line 514 of file app_sf.c.

{
    int res;
 
    res = ast_register_application_xml(readsf_name, read_sf_exec);
    res |= ast_register_application_xml(sendsf_name, sendsf_exec);
 
    return res;
}

References ast_register_application_xml, read_sf_exec(), readsf_name, sendsf_exec(), and sendsf_name.

read_sf_digits()

static int read_sf_digits ( struct ast_channel *  chan, char *  buf, int  buflen, int  timeout, int  digit_timeout, int  maxdigits, int  freq, int  features, int  extrapulses  )

static

Detects SF digits on channel using DSP.

Parameters

chan	channel on which to read digits
buf	Buffer in which to store digits
buflen	Size of buffer
timeout	ms to wait for all digits before giving up
digit_timeout	ms to wait for the next digit before giving up
maxdigits	Maximum number of digits
freq	Frequency to use
features	DSP features
extrapulses	Whether to recognize extra pulses

Return values

0	if successful
-1	if unsuccessful (including hangup).

Definition at line 215 of file app_sf.c.

{
    struct ast_dsp *dsp = NULL;
    struct ast_frame *frame = NULL;
    struct timeval start, pulsetimer, digittimer;
    int remaining_time = timeout;
    char *str = buf;
    int hits = 0, digits_read = 0;
    unsigned short int sf_on = 0;
    int res = 0;
 
    if (!(dsp = ast_dsp_new())) {
        ast_log(LOG_WARNING, "Unable to allocate DSP!\n");
        pbx_builtin_setvar_helper(chan, "RECEIVESFSTATUS", "ERROR");
        return -1;
    }
    ast_dsp_set_features(dsp, DSP_FEATURE_FREQ_DETECT);
    /* tolerance is 46 to 76% make break at 8 to 12 pps */
    ast_dsp_set_freqmode(dsp, freq, SF_MIN_DETECT, 16, 0);
 
    start = ast_tvnow();
    *str = 0; /* start with empty output buffer */
 
    while (timeout == 0 || remaining_time > 0) {
        if (timeout > 0) {
            remaining_time = ast_remaining_ms(start, timeout);
            if (remaining_time <= 0) {
                ast_debug(1, "SF all-digit timer expired\n");
                pbx_builtin_setvar_helper(chan, "RECEIVESFSTATUS", "TIMEOUT");
                break;
            }
        }
        /* If we haven't received a digit yet, don't apply the post-digit timer just yet,
         * since the sender may not have started sending any digits.
         *
         * Note that we use the digit timer, which is reset for each SF pulse,
         * as opposed to simply an entire digit being received.
         * This is done because we only want to expire the timer if there has been no activity
         * since the last digit. If we're in the middle of receiving a digit (e.g. 0)
         * we may not have a full digit yet but that should not cause an expiration. */
        if (digits_read > 0 && digit_timeout > 0) {
            int remaining_time_for_next_digit = ast_remaining_ms(digittimer, digit_timeout);
            if (remaining_time_for_next_digit <= 0) {
                ast_debug(1, "SF post-digit timer expired (>= %d ms since last SF pulse)\n", digit_timeout);
                pbx_builtin_setvar_helper(chan, "RECEIVESFSTATUS", "TIMEOUT");
                break;
            }
        }
        if (digits_read >= (buflen - 1)) { /* we don't have room to store any more digits (very unlikely to happen for a legitimate reason) */
            /* This result will probably not be usable, so status should not be START */
            pbx_builtin_setvar_helper(chan, "RECEIVESFSTATUS", "MAXDIGITS");
            break;
        }
        if (ast_waitfor(chan, 1000) > 0) {
            frame = ast_read(chan);
            if (!frame) {
                ast_debug(1, "Channel '%s' did not return a frame; probably hung up.\n", ast_channel_name(chan));
                pbx_builtin_setvar_helper(chan, "RECEIVESFSTATUS", "HANGUP");
                break;
            } else if (frame->frametype == AST_FRAME_VOICE) {
                frame = ast_dsp_process(chan, dsp, frame);
                if (frame->frametype == AST_FRAME_DTMF) {
                    char result = frame->subclass.integer;
                    if (result == 'q') {
                        sf_on = 1;
                        pulsetimer = ast_tvnow(); /* reset the pulse timer */
                        /* now, we need at least a 33ms pause to register the pulse */
                    }
                } else {
                    if (sf_on) {
                        int timeleft = ast_remaining_ms(pulsetimer, SF_MIN_OFF);
                        if (timeleft <= 0) {
                            sf_on = 0;
                            /* The pulse needs to end no more than 30ms after we detected it */
                            if (timeleft > -30) {
                                hits++;
                                digittimer = ast_tvnow(); /* reset the digit timer */
                                ast_debug(5, "Detected SF pulse (pulse #%d)\n", hits);
                                ast_dsp_free(dsp);
                                if (!(dsp = ast_dsp_new())) {
                                    ast_log(LOG_WARNING, "Unable to allocate DSP!\n");
                                    pbx_builtin_setvar_helper(chan, "RECEIVESFSTATUS", "ERROR");
                                    ast_frfree(frame);
                                    return -1;
                                }
                                ast_dsp_set_features(dsp, DSP_FEATURE_FREQ_DETECT);
                                ast_dsp_set_freqmode(dsp, freq, SF_MIN_DETECT, 16, 0);
                            } else {
                                ast_debug(5, "SF noise, ignoring, time elapsed was %d ms\n", timeleft);
                            }
                        }
                    } else if (hits > 0 && ast_remaining_ms(digittimer, SF_BETWEEN) <= 0) {
                        /* has the digit finished? */
                        ast_debug(2, "Received SF digit: %d\n", hits == 10 ? 0 : hits); /* Edge case for 10, since this is the digit '0' */
                        digits_read++;
                        if (hits > 10) {
                            if (extrapulses) {
                                /* dahdi-base.c translates 11 to * and 12 to # */
                                if (hits == 11) {
                                    hits = '*';
                                } else if (hits == 12) {
                                    hits = '#';
                                } else if (hits == 13) {
                                    hits = 'D';
                                } else if (hits == 14) {
                                    hits = 'C';
                                } else if (hits == 15) {
                                    hits = 'B';
                                } else if (hits == 16) {
                                    hits = 'A';
                                } else {
                                    ast_debug(3, "Got %d SF pulses, is someone playing with the phone?\n", hits);
                                    hits = 'A';
                                }
                                *str++ = hits;
                            } else {
                                ast_debug(2, "Got more than 10 pulses, truncating to 10\n");
                                hits = 0; /* 10 dial pulses = digit 0 */
                                *str++ = hits + '0';
                            }
                        } else {
                            if (hits == 10) {
                                hits = 0; /* 10 dial pulses = digit 0 */
                            }
                            *str++ = hits + '0';
                        }
                        *str = 0;
                        hits = 0;
                        if (maxdigits > 0 && digits_read >= maxdigits) {
                            pbx_builtin_setvar_helper(chan, "RECEIVESFSTATUS", "START");
                            ast_frfree(frame);
                            break;
                        }
                    }
                }
            }
            ast_frfree(frame);
        } else {
            pbx_builtin_setvar_helper(chan, "RECEIVESFSTATUS", "HANGUP");
            res = -1;
        }
    }
    if (dsp) {
        ast_dsp_free(dsp);
    }
    ast_debug(3, "channel '%s' - event loop stopped { timeout: %d, remaining_time: %d }\n", ast_channel_name(chan), timeout, remaining_time);
    return res;
}

References ast_channel_name(), ast_debug, ast_dsp_free(), ast_dsp_new(), ast_dsp_process(), ast_dsp_set_features(), ast_dsp_set_freqmode(), AST_FRAME_DTMF, AST_FRAME_VOICE, ast_frfree, ast_log, ast_read(), ast_remaining_ms(), ast_tvnow(), ast_waitfor(), buf, DSP_FEATURE_FREQ_DETECT, ast_frame::frametype, ast_frame_subclass::integer, LOG_WARNING, NULL, pbx_builtin_setvar_helper(), result, SF_BETWEEN, SF_MIN_DETECT, SF_MIN_OFF, str, and ast_frame::subclass.

Referenced by read_sf_exec().

read_sf_exec()

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

static

Definition at line 364 of file app_sf.c.

{
#define BUFFER_SIZE 256
    char tmp[BUFFER_SIZE] = "";
    double tosec, digitsec;
    struct ast_flags flags = {0};
    char *opt_args[OPT_ARG_ARRAY_SIZE];
    char *argcopy = NULL;
    int res, features = 0, digits = 0, to = 0, digit_timeout = 0, freq = 2600;
 
    AST_DECLARE_APP_ARGS(arglist,
        AST_APP_ARG(variable);
        AST_APP_ARG(digits);
        AST_APP_ARG(timeout);
        AST_APP_ARG(freq);
        AST_APP_ARG(options);
    );
 
    if (ast_strlen_zero(data)) {
        ast_log(LOG_WARNING, "ReceiveSF requires an argument (variable)\n");
        return -1;
    }
 
    argcopy = ast_strdupa(data);
 
    AST_STANDARD_APP_ARGS(arglist, argcopy);
 
    if (!ast_strlen_zero(arglist.options)) {
        ast_app_parse_options(read_app_options, &flags, opt_args, arglist.options);
    }
 
    if (!ast_strlen_zero(arglist.timeout)) {
        tosec = atof(arglist.timeout);
        if (tosec <= 0) {
            to = 0;
        } else {
            to = tosec * 1000.0;
        }
    }
    if (ast_test_flag(&flags, OPT_DIGIT_TIMEOUT)) {
        digitsec = (!ast_strlen_zero(opt_args[OPT_ARG_DIGIT_TIMEOUT]) ? atof(opt_args[OPT_ARG_DIGIT_TIMEOUT]) : DEFAULT_POST_DIGIT_TIMER);
        if (digitsec <= 0) {
            digit_timeout = 0;
        } else {
            digit_timeout = digitsec * 1000.0;
            if (digit_timeout < SF_BETWEEN) {
                ast_log(LOG_WARNING, "SF post-digit timer (%d) cannot be less than the SF inter-digit timeout (%d ms)\n", digit_timeout, SF_BETWEEN);
                digit_timeout = SF_BETWEEN; /* If we have a shorter timeout, it won't work at all */
            }
        }
    }
 
    if (!ast_strlen_zero(arglist.digits) && (ast_str_to_int(arglist.digits, &digits) || digits <= 0)) {
        ast_log(LOG_WARNING, "Invalid number of digits: %s\n", arglist.digits);
        return -1;
    }
 
    if (!ast_strlen_zero(arglist.freq) && (ast_str_to_int(arglist.freq, &freq) || freq <= 0)) {
        ast_log(LOG_WARNING, "Invalid freq: %s\n", arglist.freq);
        return -1;
    }
 
    if (ast_strlen_zero(arglist.variable)) {
        ast_log(LOG_WARNING, "Invalid! Usage: ReceiveSF(variable[,timeout][,option])\n");
        return -1;
    }
 
    if (ast_test_flag(&flags, OPT_DELAY)) {
        features |= DSP_DIGITMODE_MUTEMAX;
    }
 
    if (ast_test_flag(&flags, OPT_MUTE)) {
        features |= DSP_DIGITMODE_MUTECONF;
    }
 
    if (!ast_test_flag(&flags, OPT_QUELCH)) {
        features |= DSP_DIGITMODE_NOQUELCH;
    }
 
    if (ast_test_flag(&flags, OPT_RELAXED)) {
        features |= DSP_DIGITMODE_RELAXDTMF;
    }
 
    res = read_sf_digits(chan, tmp, BUFFER_SIZE, to, digit_timeout, digits, freq, features, ast_test_flag(&flags, OPT_EXTRAPULSES));
    pbx_builtin_setvar_helper(chan, arglist.variable, tmp);
    if (!ast_strlen_zero(tmp)) {
        ast_verb(3, "SF digits received: '%s'\n", tmp);
    } else if (!res) { /* if channel hung up, don't print anything out */
        ast_verb(3, "No SF digits received.\n");
    }
    return res;
}

References AST_APP_ARG, ast_app_parse_options(), AST_DECLARE_APP_ARGS, ast_log, AST_STANDARD_APP_ARGS, ast_str_to_int(), ast_strdupa, ast_strlen_zero(), ast_test_flag, ast_verb, BUFFER_SIZE, DEFAULT_POST_DIGIT_TIMER, DSP_DIGITMODE_MUTECONF, DSP_DIGITMODE_MUTEMAX, DSP_DIGITMODE_NOQUELCH, DSP_DIGITMODE_RELAXDTMF, ast_flags::flags, LOG_WARNING, NULL, OPT_ARG_ARRAY_SIZE, OPT_ARG_DIGIT_TIMEOUT, OPT_DELAY, OPT_DIGIT_TIMEOUT, OPT_EXTRAPULSES, OPT_MUTE, OPT_QUELCH, OPT_RELAXED, options, pbx_builtin_setvar_helper(), read_app_options, read_sf_digits(), and SF_BETWEEN.

Referenced by load_module().

sendsf_exec()

static int sendsf_exec ( struct ast_channel *  chan, const char *  vdata  )

static

Definition at line 457 of file app_sf.c.

{
    int res;
    char *data;
    int frequency = 2600;
    struct ast_channel *chan_found = NULL;
    struct ast_channel *chan_dest = chan;
    struct ast_channel *chan_autoservice = NULL;
    AST_DECLARE_APP_ARGS(args,
        AST_APP_ARG(digits);
        AST_APP_ARG(frequency);
        AST_APP_ARG(channel);
    );
 
    if (ast_strlen_zero(vdata)) {
        ast_log(LOG_WARNING, "SendSF requires an argument\n");
        return 0;
    }
 
    data = ast_strdupa(vdata);
    AST_STANDARD_APP_ARGS(args, data);
 
    if (ast_strlen_zero(args.digits)) {
        ast_log(LOG_WARNING, "The digits argument is required (0-9,wf)\n");
        return 0;
    }
    if (!ast_strlen_zero(args.frequency) && (ast_str_to_int(args.frequency, &frequency) || frequency < 1)) {
        ast_log(LOG_WARNING, "Invalid duration: %s\n", args.frequency);
        return -1;
    }
    if (!ast_strlen_zero(args.channel)) {
        chan_found = ast_channel_get_by_name(args.channel);
        if (!chan_found) {
            ast_log(LOG_WARNING, "No such channel: %s\n", args.channel);
            return 0;
        }
        chan_dest = chan_found;
        if (chan_found != chan) {
            chan_autoservice = chan;
        }
    }
    res = ast_sf_stream(chan_dest, chan_autoservice, NULL, args.digits, frequency, 0);
    ast_channel_cleanup(chan_found);
 
    return chan_autoservice ? 0 : res;
}

References args, AST_APP_ARG, ast_channel_cleanup, ast_channel_get_by_name(), AST_DECLARE_APP_ARGS, ast_log, ast_sf_stream(), AST_STANDARD_APP_ARGS, ast_str_to_int(), ast_strdupa, ast_strlen_zero(), ast_channel::data, LOG_WARNING, and NULL.

Referenced by load_module().

unload_module()

static int unload_module ( void  )

static

Definition at line 504 of file app_sf.c.

{
    int res;
 
    res = ast_unregister_application(readsf_name);
    res |= ast_unregister_application(sendsf_name);
 
    return res;
}

References ast_unregister_application(), readsf_name, and sendsf_name.

Variable Documentation

read_app_options

const struct ast_app_option read_app_options[128] = { [ 'd' ] = { .flag = OPT_DELAY }, [ 'e' ] = { .flag = OPT_EXTRAPULSES }, [ 'm' ] = { .flag = OPT_MUTE }, [ 't' ] = { .flag = OPT_DIGIT_TIMEOUT , .arg_index = OPT_ARG_DIGIT_TIMEOUT + 1 }, [ 'q' ] = { .flag = OPT_QUELCH }, [ 'r' ] = { .flag = OPT_RELAXED }, }

static

Definition at line 194 of file app_sf.c.

Referenced by read_sf_exec().

readsf_name

const char* readsf_name = "ReceiveSF"

static

Definition at line 196 of file app_sf.c.

Referenced by load_module(), and unload_module().

sendsf_name

const char sendsf_name[] = "SendSF"

static

Definition at line 197 of file app_sf.c.

Referenced by load_module(), and unload_module().