channel.c

	if (len > sizeof(ts->data) / 2 - 1) {
		ast_log(LOG_WARNING, "Can't generate that much data!\n");
		return -1;
	}
	memset(&ts->f, 0, sizeof(ts->f));
	for (x=0;x<len/2;x++) {
		ts->data[x] = ts->vol * (
				sin((ts->freq1 * 2.0 * M_PI / 8000.0) * (ts->pos + x)) +
				sin((ts->freq2 * 2.0 * M_PI / 8000.0) * (ts->pos + x))
			);
	}
	ts->f.frametype = AST_FRAME_VOICE;
	ts->f.subclass = AST_FORMAT_SLINEAR;
	ts->f.datalen = len;
	ts->f.samples = samples;
	ts->f.offset = AST_FRIENDLY_OFFSET;
	ts->f.data = ts->data;
	ast_write(chan, &ts->f);
	ts->pos += x;
	if (ts->duration > 0) {
		if (ts->pos >= ts->duration * 8)
			return -1;
	}
	return 0;
}

static struct ast_generator tonepair = {
	alloc: tonepair_alloc,
	release: tonepair_release,
	generate: tonepair_generator,
};

int ast_tonepair_start(struct ast_channel *chan, int freq1, int freq2, int duration, int vol)
{
	struct tonepair_def d = { 0, };
	d.freq1 = freq1;
	d.freq2 = freq2;
	d.duration = duration;
	if (vol < 1)
		d.vol = 8192;
	else
		d.vol = vol;
	if (ast_activate_generator(chan, &tonepair, &d))
		return -1;
	return 0;
}

void ast_tonepair_stop(struct ast_channel *chan)
{
	ast_deactivate_generator(chan);
}

int ast_tonepair(struct ast_channel *chan, int freq1, int freq2, int duration, int vol)
{
	struct ast_frame *f;
	int res;
	if ((res = ast_tonepair_start(chan, freq1, freq2, duration, vol)))
		return res;

	/* Give us some wiggle room */
	while(chan->generatordata && (ast_waitfor(chan, 100) >= 0)) {
		f = ast_read(chan);
		if (f)
			ast_frfree(f);
		else
			return -1;
	}
	return 0;
}

ast_group_t ast_get_group(char *s)
{
	char *copy;
	char *piece;
	char *c=NULL;
	int start=0, finish=0,x;
	ast_group_t group = 0;
	copy = ast_strdupa(s);
	if (!copy) {
		ast_log(LOG_ERROR, "Out of memory\n");
		return 0;
	}
	c = copy;
	
	while((piece = strsep(&c, ","))) {
		if (sscanf(piece, "%d-%d", &start, &finish) == 2) {
			/* Range */
		} else if (sscanf(piece, "%d", &start)) {
			/* Just one */
			finish = start;
		} else {
			ast_log(LOG_ERROR, "Syntax error parsing '%s' at '%s'.\n", s, piece);
			continue;
		}
		for (x=start;x<=finish;x++) {
			if ((x > 63) || (x < 0)) {
				ast_log(LOG_WARNING, "Ignoring invalid group %d (maximum group is 63)\n", x);
			} else
				group |= (1 << x);
		}
	}
	return group;
}

static int (*ast_moh_start_ptr)(struct ast_channel *, char *) = NULL;
static void (*ast_moh_stop_ptr)(struct ast_channel *) = NULL;
static void (*ast_moh_cleanup_ptr)(struct ast_channel *) = NULL;


void ast_install_music_functions(int (*start_ptr)(struct ast_channel *, char *),
								 void (*stop_ptr)(struct ast_channel *),
								 void (*cleanup_ptr)(struct ast_channel *)
								 ) 
{
	ast_moh_start_ptr = start_ptr;
	ast_moh_stop_ptr = stop_ptr;
	ast_moh_cleanup_ptr = cleanup_ptr;
}

void ast_uninstall_music_functions(void) 
{
	ast_moh_start_ptr = NULL;
	ast_moh_stop_ptr = NULL;
	ast_moh_cleanup_ptr = NULL;
}

/*! Turn on/off music on hold on a given channel */

int ast_moh_start(struct ast_channel *chan, char *mclass) 
{
	if(ast_moh_start_ptr)
		return ast_moh_start_ptr(chan, mclass);

	if (option_verbose > 2)
		ast_verbose(VERBOSE_PREFIX_3 "Music class %s requested but no musiconhold loaded.\n", mclass ? mclass : "default");
	
	return 0;
}

void ast_moh_stop(struct ast_channel *chan) 
{
	if(ast_moh_stop_ptr)
		ast_moh_stop_ptr(chan);
}

void ast_moh_cleanup(struct ast_channel *chan) 
{
	if(ast_moh_cleanup_ptr)
        ast_moh_cleanup_ptr(chan);
}

void ast_channels_init(void)
{
	ast_cli_register(&cli_show_channeltypes);
}

/*--- ast_print_group: Print call group and pickup group ---*/
char *ast_print_group(char *buf, int buflen, ast_group_t group) 
{
	unsigned int i;
	int first=1;
	char num[3];

	buf[0] = '\0';
	
	if (!group)	/* Return empty string if no group */
		return(buf);

	for (i=0; i<=63; i++) {	/* Max group is 63 */
		if (group & (1 << i)) {
	   		if (!first) {
				strncat(buf, ", ", buflen);
			} else {
				first=0;
	  		}
			snprintf(num, sizeof(num), "%u", i);
			strncat(buf, num, buflen);
		}
	}
	return(buf);
}