chan_h323.c

Asterisk中信道部分的源码 。。。。

		cd->redirect_number = NULL;
	}
}

static void __oh323_destroy(struct oh323_pvt *pvt)
{
	struct oh323_pvt *cur, *prev = NULL;

	AST_SCHED_DEL(sched, pvt->DTMFsched);

	if (pvt->rtp) {
		ast_rtp_destroy(pvt->rtp);
	}

	/* Free dsp used for in-band DTMF detection */
	if (pvt->vad) {
		ast_dsp_free(pvt->vad);
	}
	cleanup_call_details(&pvt->cd);

	/* Unlink us from the owner if we have one */
	if (pvt->owner) {
		ast_channel_lock(pvt->owner);
		if (h323debug)
			ast_log(LOG_DEBUG, "Detaching from %s\n", pvt->owner->name);
		pvt->owner->tech_pvt = NULL;
		ast_channel_unlock(pvt->owner);
	}
	cur = iflist;
	while(cur) {
		if (cur == pvt) {
			if (prev)
				prev->next = cur->next;
			else
				iflist = cur->next;
			break;
		}
		prev = cur;
		cur = cur->next;
	}
	if (!cur) {
		ast_log(LOG_WARNING, "%p is not in list?!?! \n", cur);
	} else {
		ast_mutex_unlock(&pvt->lock);
		ast_mutex_destroy(&pvt->lock);
		free(pvt);
	}
}

static void oh323_destroy(struct oh323_pvt *pvt)
{
	if (h323debug) {
		ast_log(LOG_DEBUG, "Destroying channel %s\n", (pvt->owner ? pvt->owner->name : "<unknown>"));
	}
	ast_mutex_lock(&iflock);
	ast_mutex_lock(&pvt->lock);
	__oh323_destroy(pvt);
	ast_mutex_unlock(&iflock);
}

static int oh323_digit_begin(struct ast_channel *c, char digit)
{
	struct oh323_pvt *pvt = (struct oh323_pvt *) c->tech_pvt;
	char *token;

	if (!pvt) {
		ast_log(LOG_ERROR, "No private structure?! This is bad\n");
		return -1;
	}
	ast_mutex_lock(&pvt->lock);
	if (pvt->rtp && (pvt->options.dtmfmode & H323_DTMF_RFC2833) && (pvt->dtmf_pt > 0)) {
		/* out-of-band DTMF */
		if (h323debug) {
			ast_log(LOG_DTMF, "Begin sending out-of-band digit %c on %s\n", digit, c->name);
		}
		ast_rtp_senddigit_begin(pvt->rtp, digit);
		ast_mutex_unlock(&pvt->lock);
	} else if (pvt->txDtmfDigit != digit) {
		/* in-band DTMF */
		if (h323debug) {
			ast_log(LOG_DTMF, "Begin sending inband digit %c on %s\n", digit, c->name);
		}
		pvt->txDtmfDigit = digit;
		token = pvt->cd.call_token ? strdup(pvt->cd.call_token) : NULL;
		ast_mutex_unlock(&pvt->lock);
		h323_send_tone(token, digit);
		if (token) {
			free(token);
		}
	} else
		ast_mutex_unlock(&pvt->lock);
	oh323_update_info(c);
	return 0;
}

/**
 * Send (play) the specified digit to the channel.
 *
 */
static int oh323_digit_end(struct ast_channel *c, char digit, unsigned int duration)
{
	struct oh323_pvt *pvt = (struct oh323_pvt *) c->tech_pvt;
	char *token;

	if (!pvt) {
		ast_log(LOG_ERROR, "No private structure?! This is bad\n");
		return -1;
	}
	ast_mutex_lock(&pvt->lock);
	if (pvt->rtp && (pvt->options.dtmfmode & H323_DTMF_RFC2833) && (pvt->dtmf_pt > 0)) {
		/* out-of-band DTMF */
		if (h323debug) {
			ast_log(LOG_DTMF, "End sending out-of-band digit %c on %s, duration %d\n", digit, c->name, duration);
		}
		ast_rtp_senddigit_end(pvt->rtp, digit);
		ast_mutex_unlock(&pvt->lock);
	} else {
		/* in-band DTMF */
		if (h323debug) {
			ast_log(LOG_DTMF, "End sending inband digit %c on %s, duration %d\n", digit, c->name, duration);
		}
		pvt->txDtmfDigit = ' ';
		token = pvt->cd.call_token ? strdup(pvt->cd.call_token) : NULL;
		ast_mutex_unlock(&pvt->lock);
		h323_send_tone(token, ' ');
		if (token) {
			free(token);
		}
	}
	oh323_update_info(c);
	return 0;
}

/**
 * Make a call over the specified channel to the specified
 * destination.
 * Returns -1 on error, 0 on success.
 */
static int oh323_call(struct ast_channel *c, char *dest, int timeout)
{
	int res = 0;
	struct oh323_pvt *pvt = (struct oh323_pvt *)c->tech_pvt;
	const char *addr;
	char called_addr[1024];

	if (h323debug) {
		ast_log(LOG_DEBUG, "Calling to %s on %s\n", dest, c->name);
	}
	if ((c->_state != AST_STATE_DOWN) && (c->_state != AST_STATE_RESERVED)) {
		ast_log(LOG_WARNING, "Line is already in use (%s)\n", c->name);
		return -1;
	}
	ast_mutex_lock(&pvt->lock);
	if (!gatekeeper_disable) {
		if (ast_strlen_zero(pvt->exten)) {
			ast_copy_string(called_addr, dest, sizeof(called_addr));
		} else {
			snprintf(called_addr, sizeof(called_addr), "%s@%s", pvt->exten, dest);
		}
	} else {
		res = htons(pvt->sa.sin_port);
		addr = ast_inet_ntoa(pvt->sa.sin_addr);
		if (ast_strlen_zero(pvt->exten)) {
			snprintf(called_addr, sizeof(called_addr), "%s:%d", addr, res);
		} else {
			snprintf(called_addr, sizeof(called_addr), "%s@%s:%d", pvt->exten, addr, res);
		}
	}
	/* make sure null terminated */
	called_addr[sizeof(called_addr) - 1] = '\0';

	if (c->cid.cid_num)
		ast_copy_string(pvt->options.cid_num, c->cid.cid_num, sizeof(pvt->options.cid_num));

	if (c->cid.cid_name)
		ast_copy_string(pvt->options.cid_name, c->cid.cid_name, sizeof(pvt->options.cid_name));

	if (c->cid.cid_rdnis) {
		ast_copy_string(pvt->options.cid_rdnis, c->cid.cid_rdnis, sizeof(pvt->options.cid_rdnis));
	}

	pvt->options.presentation = c->cid.cid_pres;
	pvt->options.type_of_number = c->cid.cid_ton;

	if ((addr = pbx_builtin_getvar_helper(c, "PRIREDIRECTREASON"))) {
		if (!strcasecmp(addr, "UNKNOWN"))
			pvt->options.redirect_reason = 0;
		else if (!strcasecmp(addr, "BUSY"))
			pvt->options.redirect_reason = 1;
		else if (!strcasecmp(addr, "NO_REPLY"))
			pvt->options.redirect_reason = 2;
		else if (!strcasecmp(addr, "UNCONDITIONAL"))
			pvt->options.redirect_reason = 15;
		else
			pvt->options.redirect_reason = -1;
	} else
		pvt->options.redirect_reason = -1;

	pvt->options.transfer_capability = c->transfercapability;

	/* indicate that this is an outgoing call */
	pvt->outgoing = 1;

	if (option_verbose > 2)
		ast_verbose(VERBOSE_PREFIX_3 "Requested transfer capability: 0x%.2x - %s\n", c->transfercapability, ast_transfercapability2str(c->transfercapability));
	if (h323debug)
		ast_log(LOG_DEBUG, "Placing outgoing call to %s, %d\n", called_addr, pvt->options.dtmfcodec);
	ast_mutex_unlock(&pvt->lock);
	res = h323_make_call(called_addr, &(pvt->cd), &pvt->options);
	if (res) {
		ast_log(LOG_NOTICE, "h323_make_call failed(%s)\n", c->name);
		return -1;
	}
	oh323_update_info(c);
	return 0;
}

static int oh323_answer(struct ast_channel *c)
{
	int res;
	struct oh323_pvt *pvt = (struct oh323_pvt *) c->tech_pvt;
	char *token;

	if (h323debug)
		ast_log(LOG_DEBUG, "Answering on %s\n", c->name);

	ast_mutex_lock(&pvt->lock);
	token = pvt->cd.call_token ? strdup(pvt->cd.call_token) : NULL;
	ast_mutex_unlock(&pvt->lock);
	res = h323_answering_call(token, 0);
	if (token)
		free(token);

	oh323_update_info(c);
	if (c->_state != AST_STATE_UP) {
		ast_setstate(c, AST_STATE_UP);
	}
	return res;
}

static int oh323_hangup(struct ast_channel *c)
{
	struct oh323_pvt *pvt = (struct oh323_pvt *) c->tech_pvt;
	int q931cause = AST_CAUSE_NORMAL_CLEARING;
	char *call_token;


	if (h323debug)
		ast_log(LOG_DEBUG, "Hanging up and scheduling destroy of call %s\n", c->name);

	if (!c->tech_pvt) {
		ast_log(LOG_WARNING, "Asked to hangup channel not connected\n");
		return 0;
	}
	ast_mutex_lock(&pvt->lock);
	/* Determine how to disconnect */
	if (pvt->owner != c) {
		ast_log(LOG_WARNING, "Huh?  We aren't the owner?\n");
		ast_mutex_unlock(&pvt->lock);
		return 0;
	}

	pvt->owner = NULL;
	c->tech_pvt = NULL;

	if (c->hangupcause) {
		q931cause = c->hangupcause;
	} else {
		const char *cause = pbx_builtin_getvar_helper(c, "DIALSTATUS");
		if (cause) {
			if (!strcmp(cause, "CONGESTION")) {
				q931cause = AST_CAUSE_NORMAL_CIRCUIT_CONGESTION;
			} else if (!strcmp(cause, "BUSY")) {
				q931cause = AST_CAUSE_USER_BUSY;
			} else if (!strcmp(cause, "CHANISUNVAIL")) {
				q931cause = AST_CAUSE_REQUESTED_CHAN_UNAVAIL;
			} else if (!strcmp(cause, "NOANSWER")) {
				q931cause = AST_CAUSE_NO_ANSWER;
			} else if (!strcmp(cause, "CANCEL")) {
				q931cause = AST_CAUSE_CALL_REJECTED;
			}
		}
	}

	/* Start the process if it's not already started */
	if (!pvt->alreadygone && !pvt->hangupcause) {
		call_token = pvt->cd.call_token ? strdup(pvt->cd.call_token) : NULL;
		if (call_token) {
			/* Release lock to eliminate deadlock */
			ast_mutex_unlock(&pvt->lock);
			if (h323_clear_call(call_token, q931cause)) {
				ast_log(LOG_WARNING, "ClearCall failed.\n");
			}
			free(call_token);
			ast_mutex_lock(&pvt->lock);
		}
	}
	pvt->needdestroy = 1;
	ast_mutex_unlock(&pvt->lock);

	/* Update usage counter */
	ast_module_unref(ast_module_info->self);

	return 0;
}

static struct ast_frame *oh323_rtp_read(struct oh323_pvt *pvt)
{
	/* Retrieve audio/etc from channel. Assumes pvt->lock is already held. */
	struct ast_frame *f;

	/* Only apply it for the first packet, we just need the correct ip/port */
	if (pvt->options.nat) {
		ast_rtp_setnat(pvt->rtp, pvt->options.nat);
		pvt->options.nat = 0;
	}

	f = ast_rtp_read(pvt->rtp);
	/* Don't send RFC2833 if we're not supposed to */
	if (f && (f->frametype == AST_FRAME_DTMF) && !(pvt->options.dtmfmode & H323_DTMF_RFC2833)) {
		return &ast_null_frame;
	}
	if (pvt->owner) {
		/* We already hold the channel lock */
		if (f->frametype == AST_FRAME_VOICE) {
			if (f->subclass != pvt->owner->nativeformats) {
				/* Try to avoid deadlock */
				if (ast_channel_trylock(pvt->owner)) {
					ast_log(LOG_NOTICE, "Format changed but channel is locked. Ignoring frame...\n");
					return &ast_null_frame;
				}
				if (h323debug)
					ast_log(LOG_DEBUG, "Oooh, format changed to %d\n", f->subclass);
				pvt->owner->nativeformats = f->subclass;
				pvt->nativeformats = f->subclass;
				ast_set_read_format(pvt->owner, pvt->owner->readformat);
				ast_set_write_format(pvt->owner, pvt->owner->writeformat);
				ast_channel_unlock(pvt->owner);
			}
			/* Do in-band DTMF detection */
			if ((pvt->options.dtmfmode & H323_DTMF_INBAND) && pvt->vad) {
				if ((pvt->nativeformats & (AST_FORMAT_SLINEAR | AST_FORMAT_ALAW | AST_FORMAT_ULAW))) {
					if (!ast_channel_trylock(pvt->owner)) {
						f = ast_dsp_process(pvt->owner, pvt->vad, f);
						ast_channel_unlock(pvt->owner);
					}
					else
						ast_log(LOG_NOTICE, "Unable to process inband DTMF while channel is locked\n");
				} else if (pvt->nativeformats && !pvt->noInbandDtmf) {
					ast_log(LOG_NOTICE, "Inband DTMF is not supported on codec %s. Use RFC2833\n", ast_getformatname(f->subclass));
					pvt->noInbandDtmf = 1;
				}
				if (f &&(f->frametype == AST_FRAME_DTMF)) {
					if (h323debug)
						ast_log(LOG_DTMF, "Received in-band digit %c.\n", f->subclass);
				}
			}
		}
	}
	return f;
}

static struct ast_frame *oh323_read(struct ast_channel *c)
{
	struct ast_frame *fr;
	struct oh323_pvt *pvt = (struct oh323_pvt *)c->tech_pvt;
	ast_mutex_lock(&pvt->lock);
	__oh323_update_info(c, pvt);
	switch(c->fdno) {
	case 0:
		fr = oh323_rtp_read(pvt);
		break;
	case 1:
		if (pvt->rtp)
			fr = ast_rtcp_read(pvt->rtp);
		else
			fr = &ast_null_frame;
		break;
	default:
		ast_log(LOG_ERROR, "Unable to handle fd %d on channel %s\n", c->fdno, c->name);
		fr = &ast_null_frame;
		break;
	}
	ast_mutex_unlock(&pvt->lock);
	return fr;
}

static int oh323_write(struct ast_channel *c, struct ast_frame *frame)
{
	struct oh323_pvt *pvt = (struct oh323_pvt *) c->tech_pvt;
	int res = 0;
	if (frame->frametype != AST_FRAME_VOICE) {
		if (frame->frametype == AST_FRAME_IMAGE) {
			return 0;
		} else {
			ast_log(LOG_WARNING, "Can't send %d type frames with H323 write\n", frame->frametype);
			return 0;
		}
	} else {
		if (!(frame->subclass & c->nativeformats)) {
			ast_log(LOG_WARNING, "Asked to transmit frame type %d, while native formats is %d (read/write = %d/%d)\n",
				frame->subclass, c->nativeformats, c->readformat, c->writeformat);
			return 0;
		}
	}
	if (pvt) {
		ast_mutex_lock(&pvt->lock);
		if (pvt->rtp && !pvt->recvonly)
			res = ast_rtp_write(pvt->rtp, frame);
		__oh323_update_info(c, pvt);
		ast_mutex_unlock(&pvt->lock);
	}
	return res;
}

static int oh323_indicate(struct ast_channel *c, int condition, const void *data, size_t datalen)
{

	struct oh323_pvt *pvt = (struct oh323_pvt *) c->tech_pvt;
	char *token = (char *)NULL;
	int res = -1;
	int got_progress;

	ast_mutex_lock(&pvt->lock);
	token = (pvt->cd.call_token ? strdup(pvt->cd.call_token) : NULL);
	got_progress = pvt->got_progress;
	if (condition == AST_CONTROL_PROGRESS)
		pvt->got_progress = 1;
	else if ((condition == AST_CONTROL_BUSY) || (condition == AST_CONTROL_CONGESTION))
		pvt->alreadygone = 1;
	ast_mutex_unlock(&pvt->lock);

	if (h323debug)
		ast_log(LOG_DEBUG, "OH323: Indicating %d on %s\n", condition, token);

	switch(condition) {
	case AST_CONTROL_RINGING:
		if (c->_state == AST_STATE_RING || c->_state == AST_STATE_RINGING) {
			h323_send_alerting(token);
			res = (got_progress ? 0 : -1);	/* Do not simulate any audio tones if we got PROGRESS message */
		}
		break;
	case AST_CONTROL_PROGRESS:
		if (c->_state != AST_STATE_UP) {
			/* Do not send PROGRESS message more than once */