channel.c

	/* XXX This is a seriously wacked out operation.  We're essentially putting the guts of
	   the clone channel into the original channel.  Start by killing off the original
	   channel's backend.   I'm not sure we're going to keep this function, because
	   while the features are nice, the cost is very high in terms of pure nastiness. XXX */

	/* We need the clone's lock, too */
	ast_channel_lock(clone);

	if (option_debug > 1)
		ast_log(LOG_DEBUG, "Got clone lock for masquerade on '%s' at %p\n", clone->name, &clone->lock);

	/* Having remembered the original read/write formats, we turn off any translation on either
	   one */
	free_translation(clone);
	free_translation(original);


	/* Unlink the masquerade */
	original->masq = NULL;
	clone->masqr = NULL;
	
	/* Save the original name */
	ast_copy_string(orig, original->name, sizeof(orig));
	/* Save the new name */
	ast_copy_string(newn, clone->name, sizeof(newn));
	/* Create the masq name */
	snprintf(masqn, sizeof(masqn), "%s<MASQ>", newn);
		
	/* Copy the name from the clone channel */
	ast_string_field_set(original, name, newn);

	/* Mangle the name of the clone channel */
	ast_string_field_set(clone, name, masqn);
	
	/* Notify any managers of the change, first the masq then the other */
	manager_event(EVENT_FLAG_CALL, "Rename", "Oldname: %s\r\nNewname: %s\r\nUniqueid: %s\r\n", newn, masqn, clone->uniqueid);
	manager_event(EVENT_FLAG_CALL, "Rename", "Oldname: %s\r\nNewname: %s\r\nUniqueid: %s\r\n", orig, newn, original->uniqueid);

	/* Swap the technologies */	
	t = original->tech;
	original->tech = clone->tech;
	clone->tech = t;

	t_pvt = original->tech_pvt;
	original->tech_pvt = clone->tech_pvt;
	clone->tech_pvt = t_pvt;

	/* Swap the readq's */
	cur = original->readq;
	original->readq = clone->readq;
	clone->readq = cur;

	/* Swap the alertpipes */
	for (i = 0; i < 2; i++) {
		x = original->alertpipe[i];
		original->alertpipe[i] = clone->alertpipe[i];
		clone->alertpipe[i] = x;
	}

	/* Swap the raw formats */
	x = original->rawreadformat;
	original->rawreadformat = clone->rawreadformat;
	clone->rawreadformat = x;
	x = original->rawwriteformat;
	original->rawwriteformat = clone->rawwriteformat;
	clone->rawwriteformat = x;

	/* Save any pending frames on both sides.  Start by counting
	 * how many we're going to need... */
	prev = NULL;
	x = 0;
	for (cur = clone->readq; cur; cur = cur->next) {
		x++;
		prev = cur;
	}
	/* If we had any, prepend them to the ones already in the queue, and
	 * load up the alertpipe */
	if (prev) {
		prev->next = original->readq;
		original->readq = clone->readq;
		clone->readq = NULL;
		if (original->alertpipe[1] > -1) {
			for (i = 0; i < x; i++)
				write(original->alertpipe[1], &x, sizeof(x));
		}
	}
	clone->_softhangup = AST_SOFTHANGUP_DEV;


	/* And of course, so does our current state.  Note we need not
	   call ast_setstate since the event manager doesn't really consider
	   these separate.  We do this early so that the clone has the proper
	   state of the original channel. */
	origstate = original->_state;
	original->_state = clone->_state;
	clone->_state = origstate;

	if (clone->tech->fixup){
		res = clone->tech->fixup(original, clone);
		if (res)
			ast_log(LOG_WARNING, "Fixup failed on channel %s, strange things may happen.\n", clone->name);
	}

	/* Start by disconnecting the original's physical side */
	if (clone->tech->hangup)
		res = clone->tech->hangup(clone);
	if (res) {
		ast_log(LOG_WARNING, "Hangup failed!  Strange things may happen!\n");
		ast_channel_unlock(clone);
		return -1;
	}
	
	snprintf(zombn, sizeof(zombn), "%s<ZOMBIE>", orig);
	/* Mangle the name of the clone channel */
	ast_string_field_set(clone, name, zombn);
	manager_event(EVENT_FLAG_CALL, "Rename", "Oldname: %s\r\nNewname: %s\r\nUniqueid: %s\r\n", masqn, zombn, clone->uniqueid);

	/* Update the type. */
	t_pvt = original->monitor;
	original->monitor = clone->monitor;
	clone->monitor = t_pvt;
	
	/* Keep the same language.  */
	ast_string_field_set(original, language, clone->language);
	/* Copy the FD's other than the generator fd */
	for (x = 0; x < AST_MAX_FDS; x++) {
		if (x != AST_GENERATOR_FD)
			original->fds[x] = clone->fds[x];
	}
	/* Move data stores over */
	if (AST_LIST_FIRST(&clone->datastores))
                AST_LIST_INSERT_TAIL(&original->datastores, AST_LIST_FIRST(&clone->datastores), entry);
	AST_LIST_HEAD_INIT_NOLOCK(&clone->datastores);

	clone_variables(original, clone);
	AST_LIST_HEAD_INIT_NOLOCK(&clone->varshead);
	/* Presense of ADSI capable CPE follows clone */
	original->adsicpe = clone->adsicpe;
	/* Bridge remains the same */
	/* CDR fields remain the same */
	/* XXX What about blocking, softhangup, blocker, and lock and blockproc? XXX */
	/* Application and data remain the same */
	/* Clone exception  becomes real one, as with fdno */
	ast_copy_flags(original, clone, AST_FLAG_EXCEPTION);
	original->fdno = clone->fdno;
	/* Schedule context remains the same */
	/* Stream stuff stays the same */
	/* Keep the original state.  The fixup code will need to work with it most likely */

	/* Just swap the whole structures, nevermind the allocations, they'll work themselves
	   out. */
	tmpcid = original->cid;
	original->cid = clone->cid;
	clone->cid = tmpcid;
	
	/* Restore original timing file descriptor */
	original->fds[AST_TIMING_FD] = original->timingfd;
	
	/* Our native formats are different now */
	original->nativeformats = clone->nativeformats;
	
	/* Context, extension, priority, app data, jump table,  remain the same */
	/* pvt switches.  pbx stays the same, as does next */
	
	/* Set the write format */
	ast_set_write_format(original, wformat);

	/* Set the read format */
	ast_set_read_format(original, rformat);

	/* Copy the music class */
	ast_string_field_set(original, musicclass, clone->musicclass);

	if (option_debug)
		ast_log(LOG_DEBUG, "Putting channel %s in %d/%d formats\n", original->name, wformat, rformat);

	/* Okay.  Last thing is to let the channel driver know about all this mess, so he
	   can fix up everything as best as possible */
	if (original->tech->fixup) {
		res = original->tech->fixup(clone, original);
		if (res) {
			ast_log(LOG_WARNING, "Channel for type '%s' could not fixup channel %s\n",
				original->tech->type, original->name);
			ast_channel_unlock(clone);
			return -1;
		}
	} else
		ast_log(LOG_WARNING, "Channel type '%s' does not have a fixup routine (for %s)!  Bad things may happen.\n",
			original->tech->type, original->name);
	
	/* Now, at this point, the "clone" channel is totally F'd up.  We mark it as
	   a zombie so nothing tries to touch it.  If it's already been marked as a
	   zombie, then free it now (since it already is considered invalid). */
	if (ast_test_flag(clone, AST_FLAG_ZOMBIE)) {
		if (option_debug)
			ast_log(LOG_DEBUG, "Destroying channel clone '%s'\n", clone->name);
		ast_channel_unlock(clone);
		manager_event(EVENT_FLAG_CALL, "Hangup",
			"Channel: %s\r\n"
			"Uniqueid: %s\r\n"
			"Cause: %d\r\n"
			"Cause-txt: %s\r\n",
			clone->name,
			clone->uniqueid,
			clone->hangupcause,
			ast_cause2str(clone->hangupcause)
			);
		ast_channel_free(clone);
	} else {
		ast_log(LOG_DEBUG, "Released clone lock on '%s'\n", clone->name);
		ast_set_flag(clone, AST_FLAG_ZOMBIE);
		ast_queue_frame(clone, &ast_null_frame);
		ast_channel_unlock(clone);
	}
	
	/* Signal any blocker */
	if (ast_test_flag(original, AST_FLAG_BLOCKING))
		pthread_kill(original->blocker, SIGURG);
	if (option_debug)
		ast_log(LOG_DEBUG, "Done Masquerading %s (%d)\n", original->name, original->_state);
	return 0;
}

void ast_set_callerid(struct ast_channel *chan, const char *callerid, const char *calleridname, const char *ani)
{
	if (callerid) {
		if (chan->cid.cid_num)
			free(chan->cid.cid_num);
		chan->cid.cid_num = ast_strdup(callerid);
	}
	if (calleridname) {
		if (chan->cid.cid_name)
			free(chan->cid.cid_name);
		chan->cid.cid_name = ast_strdup(calleridname);
	}
	if (ani) {
		if (chan->cid.cid_ani)
			free(chan->cid.cid_ani);
		chan->cid.cid_ani = ast_strdup(ani);
	}
	if (chan->cdr)
		ast_cdr_setcid(chan->cdr, chan);
	manager_event(EVENT_FLAG_CALL, "Newcallerid",
				"Channel: %s\r\n"
				"CallerID: %s\r\n"
				"CallerIDName: %s\r\n"
				"Uniqueid: %s\r\n"
				"CID-CallingPres: %d (%s)\r\n",
				chan->name,
				S_OR(chan->cid.cid_num, "<Unknown>"),
				S_OR(chan->cid.cid_name, "<Unknown>"),
				chan->uniqueid,
				chan->cid.cid_pres,
				ast_describe_caller_presentation(chan->cid.cid_pres)
				);
}

int ast_setstate(struct ast_channel *chan, int state)
{
	int oldstate = chan->_state;

	if (oldstate == state)
		return 0;

	chan->_state = state;
	ast_device_state_changed_literal(chan->name);
	manager_event(EVENT_FLAG_CALL,
		      (oldstate == AST_STATE_DOWN) ? "Newchannel" : "Newstate",
		      "Channel: %s\r\n"
		      "State: %s\r\n"
		      "CallerID: %s\r\n"
		      "CallerIDName: %s\r\n"
		      "Uniqueid: %s\r\n",
		      chan->name, ast_state2str(chan->_state),
		      S_OR(chan->cid.cid_num, "<unknown>"),
		      S_OR(chan->cid.cid_name, "<unknown>"),
		      chan->uniqueid);

	return 0;
}

/*! \brief Find bridged channel */
struct ast_channel *ast_bridged_channel(struct ast_channel *chan)
{
	struct ast_channel *bridged;
	bridged = chan->_bridge;
	if (bridged && bridged->tech->bridged_channel)
		bridged = bridged->tech->bridged_channel(chan, bridged);
	return bridged;
}

static void bridge_playfile(struct ast_channel *chan, struct ast_channel *peer, const char *sound, int remain)
{
	int min = 0, sec = 0, check;

	check = ast_autoservice_start(peer);
	if (check)
		return;

	if (remain > 0) {
		if (remain / 60 > 1) {
			min = remain / 60;
			sec = remain % 60;
		} else {
			sec = remain;
		}
	}
	
	if (!strcmp(sound,"timeleft")) {	/* Queue support */
		ast_stream_and_wait(chan, "vm-youhave", chan->language, "");
		if (min) {
			ast_say_number(chan, min, AST_DIGIT_ANY, chan->language, NULL);
			ast_stream_and_wait(chan, "queue-minutes", chan->language, "");
		}
		if (sec) {
			ast_say_number(chan, sec, AST_DIGIT_ANY, chan->language, NULL);
			ast_stream_and_wait(chan, "queue-seconds", chan->language, "");
		}
	} else {
		ast_stream_and_wait(chan, sound, chan->language, "");
	}

	ast_autoservice_stop(peer);
}

static enum ast_bridge_result ast_generic_bridge(struct ast_channel *c0, struct ast_channel *c1,
						 struct ast_bridge_config *config, struct ast_frame **fo,
						 struct ast_channel **rc, struct timeval bridge_end)
{
	/* Copy voice back and forth between the two channels. */
	struct ast_channel *cs[3];
	struct ast_frame *f;
	enum ast_bridge_result res = AST_BRIDGE_COMPLETE;
	int o0nativeformats;
	int o1nativeformats;
	int watch_c0_dtmf;
	int watch_c1_dtmf;
	void *pvt0, *pvt1;
	/* Indicates whether a frame was queued into a jitterbuffer */
	int frame_put_in_jb = 0;
	int jb_in_use;
	int to;
	
	cs[0] = c0;
	cs[1] = c1;
	pvt0 = c0->tech_pvt;
	pvt1 = c1->tech_pvt;
	o0nativeformats = c0->nativeformats;
	o1nativeformats = c1->nativeformats;
	watch_c0_dtmf = config->flags & AST_BRIDGE_DTMF_CHANNEL_0;
	watch_c1_dtmf = config->flags & AST_BRIDGE_DTMF_CHANNEL_1;

	/* Check the need of a jitterbuffer for each channel */
	jb_in_use = ast_jb_do_usecheck(c0, c1);

	for (;;) {
		struct ast_channel *who, *other;

		if ((c0->tech_pvt != pvt0) || (c1->tech_pvt != pvt1) ||
		    (o0nativeformats != c0->nativeformats) ||
		    (o1nativeformats != c1->nativeformats)) {
			/* Check for Masquerade, codec changes, etc */
			res = AST_BRIDGE_RETRY;
			break;
		}
		if (bridge_end.tv_sec) {
			to = ast_tvdiff_ms(bridge_end, ast_tvnow());
			if (to <= 0) {
				res = AST_BRIDGE_RETRY;
				break;
			}
		} else
			to = -1;
		/* Calculate the appropriate max sleep interval - in general, this is the time,
		   left to the closest jb delivery moment */
		if (jb_in_use)
			to = ast_jb_get_when_to_wakeup(c0, c1, to);
		who = ast_waitfor_n(cs, 2, &to);
		if (!who) {
			/* No frame received within the specified timeout - check if we have to deliver now */
			if (jb_in_use)
				ast_jb_get_and_deliver(c0, c1);
			if (c0->_softhangup == AST_SOFTHANGUP_UNBRIDGE || c1->_softhangup == AST_SOFTHANGUP_UNBRIDGE) {
				if (c0->_softhangup == AST_SOFTHANGUP_UNBRIDGE)
					c0->_softhangup = 0;
				if (c1->_softhangup == AST_SOFTHANGUP_UNBRIDGE)
					c1->_softhangup = 0;
				c0->_bridge = c1;
				c1->_bridge = c0;
			}
			continue;
		}
		f = ast_read(who);
		if (!f) {
			*fo = NULL;
			*rc = who;
			ast_log(LOG_DEBUG, "Didn't get a frame from channel: %s\n",who->name);
			break;
		}

		other = (who == c0) ? c1 : c0; /* the 'other' channel */
		/* Try add the frame info the who's bridged channel jitterbuff */
		if (jb_in_use)
			frame_put_in_jb = !ast_jb_put(other, f);

		if ((f->frametype == AST_FRAME_CONTROL) && !(config->flags & AST_BRIDGE_IGNORE_SIGS)) {
			int bridge_exit = 0;

			switch (f->subclass) {
			case AST_CONTROL_HOLD:
			case AST_CONTROL_UNHOLD:
			case AST_CONTROL_VIDUPDATE:
				ast_indicate_data(other, f->subclass, f->data, f->datalen);
				break;
			default:
				*fo = f;
				*rc = who;
				bridge_exit = 1;
				ast_log(LOG_DEBUG, "Got a FRAME_CONTROL (%d) frame on channel %s\n", f->subclass, who->name);
				break;
			}
			if (bridge_exit)
				break;
		}
		if ((f->frametype == AST_FRAME_VOICE) ||
		    (f->frametype == AST_FRAME_DTMF) ||
		    (f->frametype == AST_FRAME_VIDEO) ||
		    (f->frametype == AST_FRAME_IMAGE) ||
		    (f->frametype == AST_FRAME_HTML) ||
		    (f->frametype == AST_FRAME_MODEM) ||
		    (f->frametype == AST_FRAME_TEXT)) {
			/* monitored dtmf causes exit from bridge */
			int monitored_source = (who == c0) ? watch_c0_dtmf : watch_c1_dtmf;

			if (f->frametype == AST_FRAME_DTMF && monitored_source) {
				*fo = f;
				*rc = who;
				ast_log(LOG_DEBUG, "Got DTMF on channel (%s)\n", who->name);
				break;
			}
			/* Write immediately frames, not passed through jb */
			if (!frame_put_in_jb)
				ast_write(other, f);
				
			/* Check if we have to deliver now */
			if (jb_in_use)
				ast_jb_get_and_deliver(c0, c1);
		}
		/* XXX do we want to pass on also frames not matched above ? */
		ast_frfree(f);

		/* Swap who gets priority */
		cs[2] = cs[0];
		cs[0] = cs[1];
		cs[1] = cs[2];
	}
	return res;
}

/*! \brief Bridge two channels together */
enum ast_bridge_result ast_channel_bridge(struct ast_channel *c0, struct ast_channel *c1,
					  struct ast_bridge_config *config, struct ast_frame **fo, struct ast_channel **rc)
{
	struct ast_channel *who = NULL;
	enum ast_bridge_result res = AST_BRIDGE_COMPLETE;
	int nativefailed=0;
	int firstpass;
	int o0nativeformats;
	int o1nativeformats;
	long time_left_ms=0;
	struct timeval nexteventts = { 0, };
	char caller_warning = 0;
	char callee_warning = 0;
	int to;

	if (c0->_bridge) {
		ast_log(LOG_WARNING, "%s is already in a bridge with %s\n",
			c0->name, c0->_bridge->name);
		return -1;
	}
	if (c1->_bridge) {
		ast_log(LOG_WARNING, "%s is already in a bridge with %s\n",
			c1->name, c1->_bridge->name);
		return -1;
	}
	
	/* Stop if we're a zombie or need a soft hangup */
	if (ast_test_flag(c0, AST_FLAG_ZOMBIE) || ast_check_hangup_locked(c0) ||
	    ast_test_flag(c1, AST_FLAG_ZOMBIE) || ast_check_hangup_locked(c1))
		return -1;

	*fo = NULL;
	firstpass = config->firstpass;
	config->firstpass = 0;

	if (ast_tvzero(config->start_time))
		config->start_time = ast_tvnow();
	time_left_ms = config->timelimit;

	caller_warning = ast_test_flag(&config->features_caller, AST_FEATURE_PLAY_WARNING);
	callee_warning = ast_test_flag(&config->features_callee, AST_FEATURE_PLAY_WARNING);

	if (config->start_sound && firstpass) {
		if (caller_warning)
			bridge_playfile(c0, c1, config->start_sound, time_left_ms / 1000);
		if (callee_warning)
			bridge_playfile(c1, c0, config->start_sound, time_left_ms / 1000);
	}

	/* Keep track of bridge */
	c0->_bridge = c1;
	c1->_bridge = c0;

	/* \todo  XXX here should check that cid_num is not NULL */
	manager_event(EVENT_FLAG_CALL, "Link",
		      "Channel1: %s\r\n"
		      "Channel2: %s\r\n"
		      "Uniqueid1: %s\r\n"
		      "Uniqueid2: %s\r\n"
		      "CallerID1: %s\r\n"
		      "CallerID2: %s\r\n",
		      c0->name, c1->name, c0->uniqueid, c1->uniqueid, c0->cid.cid_num, c1->cid.cid_num);

	o0nativeformats = c0->nativeformats;
	o1nativeformats = c1->nativeformats;

	if (config->timelimit) {
		nexteventts = ast_tvadd(config->start_time, ast_samp2tv(config->timelimit, 1000));
		if (caller_warning || callee_warning)
			nexteventts = ast_tvsub(nexteventts, ast_samp2tv(config->play_warning, 1000));
	}

	for (/* ever */;;) {
		to = -1;
		if (config->timelimit) {
			struct timeval now;
			now = ast_tvnow();
			to = ast_tvdiff_ms(nexteventts, now);
			if (to < 0)
				to = 0;
			time_left_ms = config->timelimit - ast_tvdiff_ms(now, config->start_time);
			if (time_left_ms < to)
				to = time_left_ms;

			if (time_left_ms <= 0) {
				if (caller_warning && config->end_sound)
					bridge_playfile(c0, c1, config->end_sound, 0);
				if (callee_warning && config->end_sound)
					bridge_playfile(c1, c0, config->end_sound, 0);
				*fo = NULL;
				if (who)
					*rc = who;
				res = 0;
				break;
			}
			
			if (!to) {
				if (time_left_ms >= 5000 && config->warning_sound && config->play_warning) {
					int t = (time_left_ms + 500) / 1000; /* round to nearest second */
					if (caller_warning)
						bridge_playfile(c0, c1, config->warning_sound, t);
					if (callee_warning)
						bridge_playfile(c1, c0, config->warning_sound, t);
				}
				if (config->warning_freq) {
					nexteventts = ast_tvadd(nexteventts, ast_samp2tv(config->warning_freq, 1000));
				} else
					nexteventts = ast_tvadd(config->start_time, ast_samp2tv(config->timelimit, 1000));
			}
		}

		if (c0->_softhangup == AST_SOFTHANGUP_UNBRIDGE || c1->_softhangup == AST_SOFTHANGUP_UNBRIDGE) {
			if (c0->_softhangup == AST_SOFTHANGUP_UNBRIDGE)
				c0->_softhangup = 0;
			if (c1->_softhangup == AST_SOFTHANGUP_UNBRIDGE)
				c1->_softhangup = 0;
			c0->_bridge = c1;
			c1->_bridge = c0;
			ast_log(LOG_DEBUG, "Unbridge signal received. Ending native bridge.\n");
			continue;
		}
		
		/* Stop if we're a zombie or need a soft hangup */
		if (ast_test_flag(c0, AST_FLAG_ZOMBIE) || ast_check_hangup_locked(c0) ||
		    ast_test_flag(c1, AST_FLAG_ZOMBIE) || ast_check_hangup_locked(c1)) {
			*fo = NULL;
			if (who)
				*rc = who;
			res = 0;
			ast_log(LOG_DEBUG, "Bridge stops because we're zombie or need a soft hangup: c0=%s, c1=%s, flags: %s,%s,%s,%s\n",
				c0->name, c1->name,
				ast_test_flag(c0, AST_FLAG_ZOMBIE) ? "Yes" : "No",
				ast_check_hangup(c0) ? "Yes" : "No",
				ast_test_flag(c1, AST_FLAG_ZOMBIE) ? "Yes" : "No",
				ast_check_hangup(c1) ? "Yes" : "No");
			break;
		}

		if (c0->tech->bridge &&
		    (config->timelimit == 0) &&
		    (c0->tech->bridge == c1->tech->bridge) &&
		    !nativefailed && !c0->monitor && !c1->monitor &&
		    !c0->spies && !c1->spies) {
			/* Looks like they share a bridge method and nothing else is in the way */
			ast_set_flag(c0, AST_FLAG_NBRIDGE);
			ast_set_flag(c1, AST_FLAG_NBRIDGE);
			if ((res = c0->tech->bridge(c0, c1, config->flags, fo, rc, to)) == AST_BRIDGE_COMPLETE) {
				/* \todo  XXX here should check that cid_num is not NULL */
				manager_event(EVENT_FLAG_CALL, "Unlink",
					      "Channel1: %s\r\n"
					      "Channel2: %s\r\n"
					      "Uniqueid1: %s\r\n"
					      "Uniqueid2: %s\r\n"
					      "CallerID1: %s\r\n"
					      "CallerID2: %s\r\n",
					      c0->name, c1->name, c0->uniqueid, c1->uniqueid, c0->cid.cid_num, c1->cid.cid_num);
				ast_log(LOG_DEBUG, "Returning from native bridge, channels: %s, %s\n", c0->name, c1->name);

				ast_clear_flag(c0, AST_FLAG_NBRIDGE);
				ast_clear_flag(c1, AST_FLAG_NBRIDGE);

				if (c0->_softhangup == AST_SOFTHANGUP_UNBRIDGE || c1->_softhangup == AST_SOFTHANGUP_UNBRIDGE)
					continue;

				c0->_bridge = NULL;
				c1->_bridge = NULL;

				return res;
			} else {
				ast_clear_flag(c0, AST_FLAG_NBRIDGE);
				ast_clear_flag(c1, AST_FLAG_NBRIDGE);
			}
			switch (res) {
			case AST_BRIDGE_RETRY:
				continue;
			default:
				if (option_verbose > 2)
					ast_verbose(VERBOSE_PREFIX_3 "Native bridging %s and %s ended\n",
						    c0->name, c1->name);
				/* fallthrough */
			case AST_BRIDGE_FAILED_NOWARN:
				nativefailed++;
				break;
			}
		}
	
		if (((c0->writeformat != c1->readformat) || (c0->readformat != c1->writeformat) ||
		    (c0->nativeformats != o0nativeformats) || (c1->nativeformats != o1nativeformats)) &&
		    !(c0->generator || c1->generator)) {
			if (ast_channel_make_compatible(c0, c1)) {
				ast_log(LOG_WARNING, "Can't make %s and %s compatible\n", c0->name, c1->name);
				/* \todo  XXX here should check that cid_num is not NULL */
                                manager_event(EVENT_FLAG_CALL, "Unlink",
					      "Channel1: %s\r\n"
					      "Channel2: %s\r\n"
					      "Uniqueid1: %s\r\n"
					      "Uniqueid2: %s\r\n"
					      "CallerID1: %s\r\n"
					      "CallerID2: %s\r\n",
					      c0->name, c1->name, c0->uniqueid, c1->uniqueid, c0->cid.cid_num, c1->cid.cid_num);
				return AST_BRIDGE_FAILED;
			}
			o0nativeformats = c0->nativeformats;
			o1nativeformats = c1->nativeformats;
		}
		res = ast_generic_bridge(c0, c1, config, fo, rc, nexteventts);
		if (res != AST_BRIDGE_RETRY)
			break;
	}

	c0->_bridge = NULL;
	c1->_bridge = NULL;

	/* \todo  XXX here should check that cid_num is not NULL */
	manager_event(EVENT_FLAG_CALL, "Unlink",
		      "Channel1: %s\r\n"
		      "Channel2: %s\r\n"
		      "Uniqueid1: %s\r\n"
		      "Uniqueid2: %s\r\n"
		      "CallerID1: %s\r\n"
		      "CallerID2: %s\r\n",
		      c0->name, c1->name, c0->uniqueid, c1->uniqueid, c0->cid.cid_num, c1->cid.cid_num);
	ast_log(LOG_DEBUG, "Bridge stops bridging channels %s and %s\n", c0->name, c1->name);

	return res;
}

/*! \brief Sets an option on a channel */
int ast_channel_setoption(struct ast_channel *chan, int option, void *data, int datalen, int block)
{
	int res;

	if (chan->tech->setoption) {
		res = chan->tech->setoption(chan, option, data, datalen);
		if (res < 0)
			return res;
	} else {
		errno = ENOSYS;
		return -1;
	}
	if (block) {
		/* XXX Implement blocking -- just wait for our option frame reply, discarding
		   intermediate packets. XXX */
		ast_log(LOG_ERROR, "XXX Blocking not implemented yet XXX\n");
		return -1;
	}
	return 0;
}

struct tonepair_def {
	int freq1;
	int freq2;
	int duration;
	int vol;
};

struct tonepair_state {
	float freq1;
	float freq2;
	float vol;
	int duration;
	int pos;
	int origwfmt;
	struct ast_frame f;
	unsigned char offset[AST_FRIENDLY_OFFSET];
	short data[4000];
};

static void tonepair_release(struct ast_channel *chan, void *params)
{
	struct tonepair_state *ts = params;

	if (chan)
		ast_set_write_format(chan, ts->origwfmt);
	free(ts);
}

static void *tonepair_alloc(struct ast_channel *chan, void *params)
{
	struct tonepair_state *ts;
	struct tonepair_def *td = params;

	if (!(ts = ast_calloc(1, sizeof(*ts))))
		return NULL;
	ts->origwfmt = chan->writeformat;
	if (ast_set_write_format(chan, AST_FORMAT_SLINEAR)) {
		ast_log(LOG_WARNING, "Unable to set '%s' to signed linear format (write)\n", chan->name);
		tonepair_release(NULL, ts);
		ts = NULL;
	} else {
		ts->freq1 = td->freq1;
		ts->freq2 = td->freq2;
		ts->duration = td->duration;
		ts->vol = td->vol;
	}
	/* Let interrupts interrupt :) */
	ast_set_flag(chan, AST_FLAG_WRITE_INT);
	return ts;
}

static int tonepair_generator(struct ast_channel *chan, void *data, int len, int samples)
{
	struct tonepair_state *ts = data;
	int x;

	/* we need to prepare a frame with 16 * timelen samples as we're
	 * generating SLIN audio
	 */
	len = samples * 2;

	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;
	d.vol = (vol < 1) ? 8192 : vol; /* force invalid to 8192 */
	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)
{
	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) {
		struct ast_frame *f = ast_read(chan);
		if (f)
			ast_frfree(f);
		else
			return -1;
	}
	return 0;
}

ast_group_t ast_get_group(char *s)
{
	char *piece;
	char *c;
	int start=0, finish=0, x;
	ast_group_t group = 0;

	c = ast_strdupa(s);
	
	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 group configuration '%s' at '%s'. Ignoring.\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 |= ((ast_group_t) 1 << x);
		}
	}
	return group;
}

static int (*ast_moh_start_ptr)(struct ast_channel *, const 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 *, const 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;
}

/*! \brief Turn on music on hold on a given channel */
int ast_moh_start(struct ast_channel *chan, const 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;
}

/*! \brief Turn off music on hold on a given channel */
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_cli_register(&cli_show_channeltype);
}

/*! \brief 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 & ((ast_group_t) 1 << i)) {
	   		if (!first) {
				strncat(buf, ", ", buflen);
			} else {
				first=0;
	  		}
			snprintf(num, sizeof(num), "%u", i);
			strncat(buf, num, buflen);
		}
	}
	return buf;
}

void ast_set_variables(struct ast_channel *chan, struct ast_variable *vars)
{
	struct ast_variable *cur;

	for (cur = vars; cur; cur = cur->next)
		pbx_builtin_setvar_helper(chan, cur->name, cur->value);	
}

static void copy_data_from_queue(struct ast_channel_spy_queue *queue, short *buf, unsigned int samples)
{
	struct ast_frame *f;
	int tocopy;
	int bytestocopy;

	while (samples) {
		f = queue->head;

		if (!f) {
			ast_log(LOG_ERROR, "Ran out of frames before buffer filled!\n");
			break;
		}

		tocopy = (f->samples > samples) ? samples : f->samples;
		bytestocopy = ast_codec_get_len(queue->format, tocopy);
		memcpy(buf, f->data, bytestocopy);
		samples -= tocopy;
		buf += tocopy;
		f->samples -= tocopy;
		f->data += bytestocopy;
		f->datalen -= bytestocopy;
		f->offset += bytestocopy;
		queue->samples -= tocopy;
		if (!f->samples) {
			queue->head = f->next;
			ast_frfree(f);
		}
	}
}

struct ast_frame *ast_channel_spy_read_frame(struct ast_channel_spy *spy, unsigned int samples)
{
	struct ast_frame *result;
	/* buffers are allocated to hold SLINEAR, which is the largest format */
        short read_buf[samples];
        short write_buf[samples];
	struct ast_frame *read_frame;
	struct ast_frame *write_frame;
	int need_dup;
	struct ast_frame stack_read_frame = { .frametype = AST_FRAME_VOICE,
					      .subclass = spy->read_queue.format,
					      .data = read_buf,
					      .samples = samples,
					      .datalen = ast_codec_get_len(spy->read_queue.format, samples),
	};
	struct ast_frame stack_write_frame = { .frametype = AST_FRAME_VOICE,