sig_pri.c

	} else {
		ast_free(ast_channel_dialed(chan)->number.str);
		ast_channel_dialed(chan)->number.str = ast_strdup(exten);

		if (p->pri->append_msn_to_user_tag && p->pri->nodetype != PRI_NETWORK) {
			/*
			 * Update the user tag for party id's from this device for this call
			 * now that we have a complete MSN from the network.
			 */
			snprintf(p->user_tag, sizeof(p->user_tag), "%s_%s", p->pri->initial_user_tag,
				exten);
			ast_free(ast_channel_caller(chan)->id.tag);
			ast_channel_caller(chan)->id.tag = ast_strdup(p->user_tag);
		}
	}
	sig_pri_play_tone(p, -1);
	if (ast_exists_extension(chan, ast_channel_context(chan), exten, 1, p->cid_num)) {
		/* Start the real PBX */
		ast_channel_exten_set(chan, exten);
		sig_pri_dsp_reset_and_flush_digits(p);
#if defined(ISSUE_16789)
		/*
		 * Conditionaled out this code to effectively revert the Mantis
		 * issue 16789 change.  It breaks overlap dialing through
		 * Asterisk.  There is not enough information available at this
		 * point to know if dialing is complete.  The
		 * ast_exists_extension(), ast_matchmore_extension(), and
		 * ast_canmatch_extension() calls are not adequate to detect a
		 * dial through extension pattern of "_9!".
		 *
		 * Workaround is to use the dialplan Proceeding() application
		 * early on non-dial through extensions.
		 */
		if ((p->pri->overlapdial & DAHDI_OVERLAPDIAL_INCOMING)
			&& !ast_matchmore_extension(chan, ast_channel_context(chan), exten, 1, p->cid_num)) {
			sig_pri_lock_private(p);
			if (p->pri->pri) {
				pri_grab(p, p->pri);
				if (p->call_level < SIG_PRI_CALL_LEVEL_PROCEEDING) {
					p->call_level = SIG_PRI_CALL_LEVEL_PROCEEDING;
				}
				pri_proceeding(p->pri->pri, p->call, PVT_TO_CHANNEL(p), 0);
				pri_rel(p->pri);
			}
			sig_pri_unlock_private(p);
		}
#endif	/* defined(ISSUE_16789) */

		sig_pri_set_echocanceller(p, 1);
		ast_setstate(chan, AST_STATE_RING);
		res = ast_pbx_run(chan);
		if (res) {
			ast_log(LOG_WARNING, "PBX exited non-zero!\n");
		}
	} else {
		ast_debug(1, "No such possible extension '%s' in context '%s'\n", exten, ast_channel_context(chan));
		ast_channel_hangupcause_set(chan, AST_CAUSE_UNALLOCATED);
		ast_hangup(chan);
		p->exten[0] = '\0';
		/* Since we send release complete here, we won't get one */
		p->call = NULL;
		ast_mutex_lock(&p->pri->lock);
		sig_pri_span_devstate_changed(p->pri);
		ast_mutex_unlock(&p->pri->lock);
	}
	return NULL;
}

void pri_event_alarm(struct sig_pri_span *pri, int index, int before_start_pri)
{
	pri->dchanavail[index] &= ~(DCHAN_NOTINALARM | DCHAN_UP);
	if (!before_start_pri) {
		pri_find_dchan(pri);
	}
}

void pri_event_noalarm(struct sig_pri_span *pri, int index, int before_start_pri)
{
	pri->dchanavail[index] |= DCHAN_NOTINALARM;
	if (!before_start_pri)
		pri_restart(pri->dchans[index]);
}

/*!
 * \internal
 * \brief Convert libpri party name into asterisk party name.
 * \since 1.8
 *
 * \param ast_name Asterisk party name structure to fill.  Must already be set initialized.
 * \param pri_name libpri party name structure containing source information.
 *
 * \note The filled in ast_name structure needs to be destroyed by
 * ast_party_name_free() when it is no longer needed.
 *
 * \return Nothing
 */
static void sig_pri_party_name_convert(struct ast_party_name *ast_name, const struct pri_party_name *pri_name)
{
	ast_name->str = ast_strdup(pri_name->str);
	ast_name->char_set = pri_to_ast_char_set(pri_name->char_set);
	ast_name->presentation = pri_to_ast_presentation(pri_name->presentation);
	ast_name->valid = 1;
}

/*!
 * \internal
 * \brief Convert libpri party number into asterisk party number.
 * \since 1.8
 *
 * \param ast_number Asterisk party number structure to fill.  Must already be set initialized.
 * \param pri_number libpri party number structure containing source information.
 * \param pri PRI span control structure.
 *
 * \note The filled in ast_number structure needs to be destroyed by
 * ast_party_number_free() when it is no longer needed.
 *
 * \return Nothing
 */
static void sig_pri_party_number_convert(struct ast_party_number *ast_number, const struct pri_party_number *pri_number, struct sig_pri_span *pri)
{
	char number[AST_MAX_EXTENSION];

	apply_plan_to_existing_number(number, sizeof(number), pri, pri_number->str,
		pri_number->plan);
	ast_number->str = ast_strdup(number);
	ast_number->plan = pri_number->plan;
	ast_number->presentation = pri_to_ast_presentation(pri_number->presentation);
	ast_number->valid = 1;
}

/*!
 * \internal
 * \brief Convert libpri party id into asterisk party id.
 * \since 1.8
 *
 * \param ast_id Asterisk party id structure to fill.  Must already be set initialized.
 * \param pri_id libpri party id structure containing source information.
 * \param pri PRI span control structure.
 *
 * \note The filled in ast_id structure needs to be destroyed by
 * ast_party_id_free() when it is no longer needed.
 *
 * \return Nothing
 */
static void sig_pri_party_id_convert(struct ast_party_id *ast_id, const struct pri_party_id *pri_id, struct sig_pri_span *pri)
{
	if (pri_id->name.valid) {
		sig_pri_party_name_convert(&ast_id->name, &pri_id->name);
	}
	if (pri_id->number.valid) {
		sig_pri_party_number_convert(&ast_id->number, &pri_id->number, pri);
	}
#if defined(HAVE_PRI_SUBADDR)
	if (pri_id->subaddress.valid) {
		sig_pri_set_subaddress(&ast_id->subaddress, &pri_id->subaddress);
	}
#endif	/* defined(HAVE_PRI_SUBADDR) */
}

/*!
 * \internal
 * \brief Convert libpri redirecting information into asterisk redirecting information.
 * \since 1.8
 *
 * \param ast_redirecting Asterisk redirecting structure to fill.
 * \param pri_redirecting libpri redirecting structure containing source information.
 * \param ast_guide Asterisk redirecting structure to use as an initialization guide.
 * \param pri PRI span control structure.
 *
 * \note The filled in ast_redirecting structure needs to be destroyed by
 * ast_party_redirecting_free() when it is no longer needed.
 *
 * \return Nothing
 */
static void sig_pri_redirecting_convert(struct ast_party_redirecting *ast_redirecting,
	const struct pri_party_redirecting *pri_redirecting,
	const struct ast_party_redirecting *ast_guide,
	struct sig_pri_span *pri)
{
	ast_party_redirecting_set_init(ast_redirecting, ast_guide);

	sig_pri_party_id_convert(&ast_redirecting->orig, &pri_redirecting->orig_called, pri);
	sig_pri_party_id_convert(&ast_redirecting->from, &pri_redirecting->from, pri);
	sig_pri_party_id_convert(&ast_redirecting->to, &pri_redirecting->to, pri);
	ast_redirecting->count = pri_redirecting->count;
	ast_redirecting->reason = pri_to_ast_reason(pri_redirecting->reason);
	ast_redirecting->orig_reason = pri_to_ast_reason(pri_redirecting->orig_reason);
}

/*!
 * \internal
 * \brief Determine if the given extension matches one of the MSNs in the pattern list.
 * \since 1.8
 *
 * \param msn_patterns Comma separated list of MSN patterns to match.
 * \param exten Extension to match in the MSN list.
 *
 * \retval 1 if matches.
 * \retval 0 if no match.
 */
static int sig_pri_msn_match(const char *msn_patterns, const char *exten)
{
	char *pattern;
	char *msn_list;
	char *list_tail;

	msn_list = ast_strdupa(msn_patterns);

	list_tail = NULL;
	pattern = strtok_r(msn_list, ",", &list_tail);
	while (pattern) {
		pattern = ast_strip(pattern);
		if (!ast_strlen_zero(pattern) && ast_extension_match(pattern, exten)) {
			/* Extension matched the pattern. */
			return 1;
		}
		pattern = strtok_r(NULL, ",", &list_tail);
	}
	/* Did not match any pattern in the list. */
	return 0;
}

#if defined(HAVE_PRI_MCID)
/*!
 * \internal
 * \brief Append the given party id to the event string.
 * \since 1.8
 *
 * \param msg Event message string being built.
 * \param prefix Prefix to add to the party id lines.
 * \param party Party information to encode.
 *
 * \return Nothing
 */
static void sig_pri_event_party_id(struct ast_str **msg, const char *prefix, struct ast_party_id *party)
{
	int pres;

	/* Combined party presentation */
	pres = ast_party_id_presentation(party);
	ast_str_append(msg, 0, "%sPres: %d (%s)\r\n", prefix, pres,
		ast_describe_caller_presentation(pres));

	/* Party number */
	ast_str_append(msg, 0, "%sNumValid: %d\r\n", prefix,
		(unsigned) party->number.valid);
	ast_str_append(msg, 0, "%sNum: %s\r\n", prefix,
		S_COR(party->number.valid, party->number.str, ""));
	ast_str_append(msg, 0, "%ston: %d\r\n", prefix, party->number.plan);
	if (party->number.valid) {
		ast_str_append(msg, 0, "%sNumPlan: %d\r\n", prefix, party->number.plan);
		ast_str_append(msg, 0, "%sNumPres: %d (%s)\r\n", prefix,
			party->number.presentation,
			ast_describe_caller_presentation(party->number.presentation));
	}

	/* Party name */
	ast_str_append(msg, 0, "%sNameValid: %d\r\n", prefix,
		(unsigned) party->name.valid);
	ast_str_append(msg, 0, "%sName: %s\r\n", prefix,
		S_COR(party->name.valid, party->name.str, ""));
	if (party->name.valid) {
		ast_str_append(msg, 0, "%sNameCharSet: %s\r\n", prefix,
			ast_party_name_charset_describe(party->name.char_set));
		ast_str_append(msg, 0, "%sNamePres: %d (%s)\r\n", prefix,
			party->name.presentation,
			ast_describe_caller_presentation(party->name.presentation));
	}

#if defined(HAVE_PRI_SUBADDR)
	/* Party subaddress */
	if (party->subaddress.valid) {
		static const char subaddress[] = "Subaddr";

		ast_str_append(msg, 0, "%s%s: %s\r\n", prefix, subaddress,
			S_OR(party->subaddress.str, ""));
		ast_str_append(msg, 0, "%s%sType: %d\r\n", prefix, subaddress,
			party->subaddress.type);
		ast_str_append(msg, 0, "%s%sOdd: %d\r\n", prefix, subaddress,
			party->subaddress.odd_even_indicator);
	}
#endif	/* defined(HAVE_PRI_SUBADDR) */
}
#endif	/* defined(HAVE_PRI_MCID) */

#if defined(HAVE_PRI_MCID)
/*!
 * \internal
 * \brief Handle the MCID event.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param mcid MCID event parameters.
 * \param owner Asterisk channel associated with the call.
 * NULL if Asterisk no longer has the ast_channel struct.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the owner channel lock is already obtained if still present.
 *
 * \return Nothing
 */
static void sig_pri_mcid_event(struct sig_pri_span *pri, const struct pri_subcmd_mcid_req *mcid, struct ast_channel *owner)
{
	struct ast_channel *chans[1];
	struct ast_str *msg;
	struct ast_party_id party;

	msg = ast_str_create(4096);
	if (!msg) {
		return;
	}

	if (owner) {
		/*
		 * The owner channel is present.
		 * Pass the event to the peer as well.
		 */
		ast_queue_control(owner, AST_CONTROL_MCID);

		ast_str_append(&msg, 0, "Channel: %s\r\n", ast_channel_name(owner));
		ast_str_append(&msg, 0, "UniqueID: %s\r\n", ast_channel_uniqueid(owner));

		sig_pri_event_party_id(&msg, "CallerID", &ast_channel_connected(owner)->id);
	} else {
		/*
		 * Since we no longer have an owner channel,
		 * we have to use the caller information supplied by libpri.
		 */
		ast_party_id_init(&party);
		sig_pri_party_id_convert(&party, &mcid->originator, pri);
		sig_pri_event_party_id(&msg, "CallerID", &party);
		ast_party_id_free(&party);
	}

	/* Always use libpri's called party information. */
	ast_party_id_init(&party);
	sig_pri_party_id_convert(&party, &mcid->answerer, pri);
	sig_pri_event_party_id(&msg, "ConnectedID", &party);
	ast_party_id_free(&party);

	chans[0] = owner;
	ast_manager_event_multichan(EVENT_FLAG_CALL, "MCID", owner ? 1 : 0, chans, "%s",
		ast_str_buffer(msg));
	ast_free(msg);
}
#endif	/* defined(HAVE_PRI_MCID) */

#if defined(HAVE_PRI_TRANSFER)
struct xfer_rsp_data {
	struct sig_pri_span *pri;
	/*! Call to send transfer success/fail response over. */
	q931_call *call;
	/*! Invocation ID to use when sending a reply to the transfer request. */
	int invoke_id;
};
#endif	/* defined(HAVE_PRI_TRANSFER) */

#if defined(HAVE_PRI_TRANSFER)
/*!
 * \internal
 * \brief Send the transfer success/fail response message.
 * \since 1.8
 *
 * \param data Callback user data pointer
 * \param is_successful TRUE if the transfer was successful.
 *
 * \return Nothing
 */
static void sig_pri_transfer_rsp(void *data, int is_successful)
{
	struct xfer_rsp_data *rsp = data;

	pri_transfer_rsp(rsp->pri->pri, rsp->call, rsp->invoke_id, is_successful);
}
#endif	/* defined(HAVE_PRI_TRANSFER) */

#if defined(HAVE_PRI_CALL_HOLD) || defined(HAVE_PRI_TRANSFER)
/*!
 * \brief Protocol callback to indicate if transfer will happen.
 * \since 1.8
 *
 * \param data Callback user data pointer
 * \param is_successful TRUE if the transfer will happen.
 *
 * \return Nothing
 */
typedef void (*xfer_rsp_callback)(void *data, int is_successful);
#endif	/* defined(HAVE_PRI_CALL_HOLD) || defined(HAVE_PRI_TRANSFER) */

#if defined(HAVE_PRI_CALL_HOLD) || defined(HAVE_PRI_TRANSFER)
/*!
 * \internal
 * \brief Attempt to transfer the two calls to each other.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param call_1_pri First call involved in the transfer. (transferee; usually on hold)
 * \param call_1_held TRUE if call_1_pri is on hold.
 * \param call_2_pri Second call involved in the transfer. (target; usually active/ringing)
 * \param call_2_held TRUE if call_2_pri is on hold.
 * \param rsp_callback Protocol callback to indicate if transfer will happen. NULL if not used.
 * \param data Callback user data pointer
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int sig_pri_attempt_transfer(struct sig_pri_span *pri, q931_call *call_1_pri, int call_1_held, q931_call *call_2_pri, int call_2_held, xfer_rsp_callback rsp_callback, void *data)
{
	struct attempt_xfer_call {
		q931_call *pri;
		struct ast_channel *ast;
		int held;
		int chanpos;
	};
	int retval;
	struct ast_channel *transferee;
	struct attempt_xfer_call *call_1;
	struct attempt_xfer_call *call_2;
	struct attempt_xfer_call *swap_call;
	struct attempt_xfer_call c1;
	struct attempt_xfer_call c2;

	c1.pri = call_1_pri;
	c1.held = call_1_held;
	call_1 = &c1;

	c2.pri = call_2_pri;
	c2.held = call_2_held;
	call_2 = &c2;

	call_1->chanpos = pri_find_principle_by_call(pri, call_1->pri);
	call_2->chanpos = pri_find_principle_by_call(pri, call_2->pri);
	if (call_1->chanpos < 0 || call_2->chanpos < 0) {
		/* Calls not found in span control. */
		if (rsp_callback) {
			/* Transfer failed. */
			rsp_callback(data, 0);
		}
		return -1;
	}

	/* Attempt to make transferee and target consistent. */
	if (!call_1->held && call_2->held) {
		/*
		 * Swap call_1 and call_2 to make call_1 the transferee(held call)
		 * and call_2 the target(active call).
		 */
		swap_call = call_1;
		call_1 = call_2;
		call_2 = swap_call;
	}

	/* Deadlock avoidance is attempted. */
	sig_pri_lock_private(pri->pvts[call_1->chanpos]);
	sig_pri_lock_owner(pri, call_1->chanpos);
	sig_pri_lock_private(pri->pvts[call_2->chanpos]);
	sig_pri_lock_owner(pri, call_2->chanpos);

	call_1->ast = pri->pvts[call_1->chanpos]->owner;
	call_2->ast = pri->pvts[call_2->chanpos]->owner;
	if (!call_1->ast || !call_2->ast) {
		/* At least one owner is not present. */
		if (call_1->ast) {
			ast_channel_unlock(call_1->ast);
		}
		if (call_2->ast) {
			ast_channel_unlock(call_2->ast);
		}
		sig_pri_unlock_private(pri->pvts[call_1->chanpos]);
		sig_pri_unlock_private(pri->pvts[call_2->chanpos]);
		if (rsp_callback) {
			/* Transfer failed. */
			rsp_callback(data, 0);
		}
		return -1;
	}

	for (;;) {
		transferee = ast_bridged_channel(call_1->ast);
		if (transferee) {
			break;
		}

		/* Try masquerading the other way. */
		swap_call = call_1;
		call_1 = call_2;
		call_2 = swap_call;

		transferee = ast_bridged_channel(call_1->ast);
		if (transferee) {
			break;
		}

		/* Could not transfer.  Neither call is bridged. */
		ast_channel_unlock(call_1->ast);
		ast_channel_unlock(call_2->ast);
		sig_pri_unlock_private(pri->pvts[call_1->chanpos]);
		sig_pri_unlock_private(pri->pvts[call_2->chanpos]);

		if (rsp_callback) {
			/* Transfer failed. */
			rsp_callback(data, 0);
		}
		return -1;
	}

	ast_verb(3, "TRANSFERRING %s to %s\n", ast_channel_name(call_1->ast), ast_channel_name(call_2->ast));

	/*
	 * Setup transfer masquerade.
	 *
	 * Note:  There is an extremely nasty deadlock avoidance issue
	 * with ast_channel_transfer_masquerade().  Deadlock may be possible if
	 * the channels involved are proxies (chan_agent channels) and
	 * it is called with locks.  Unfortunately, there is no simple
	 * or even merely difficult way to guarantee deadlock avoidance
	 * and still be able to send an ECT success response without the
	 * possibility of the bridged channel hanging up on us.
	 */
	ast_mutex_unlock(&pri->lock);
	retval = ast_channel_transfer_masquerade(
		call_2->ast,
		ast_channel_connected(call_2->ast),
		call_2->held,
		transferee,
		ast_channel_connected(call_1->ast),
		call_1->held);

	/* Reacquire the pri->lock to hold off completion of the transfer masquerade. */
	ast_mutex_lock(&pri->lock);

	ast_channel_unlock(call_1->ast);
	ast_channel_unlock(call_2->ast);
	sig_pri_unlock_private(pri->pvts[call_1->chanpos]);
	sig_pri_unlock_private(pri->pvts[call_2->chanpos]);

	if (rsp_callback) {
		/*
		 * Report transfer status.
		 *
		 * Must do the callback before the masquerade completes to ensure
		 * that the protocol message goes out before the call leg is
		 * disconnected.
		 */
		rsp_callback(data, retval ? 0 : 1);
	}
	return retval;
}
#endif	/* defined(HAVE_PRI_CALL_HOLD) || defined(HAVE_PRI_TRANSFER) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Compare the CC agent private data by libpri cc_id.
 * \since 1.8
 *
 * \param obj pointer to the (user-defined part) of an object.
 * \param arg callback argument from ao2_callback()
 * \param flags flags from ao2_callback()
 *
 * \return values are a combination of enum _cb_results.
 */
static int sig_pri_cc_agent_cmp_cc_id(void *obj, void *arg, int flags)
{
	struct ast_cc_agent *agent_1 = obj;
	struct sig_pri_cc_agent_prv *agent_prv_1 = agent_1->private_data;
	struct sig_pri_cc_agent_prv *agent_prv_2 = arg;

	return (agent_prv_1 && agent_prv_1->pri == agent_prv_2->pri
		&& agent_prv_1->cc_id == agent_prv_2->cc_id) ? CMP_MATCH | CMP_STOP : 0;
}
#endif	/* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Find the CC agent by libpri cc_id.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param cc_id CC record ID to find.
 *
 * \note
 * Since agents are refcounted, and this function returns
 * a reference to the agent, it is imperative that you decrement
 * the refcount of the agent once you have finished using it.
 *
 * \retval agent on success.
 * \retval NULL not found.
 */
static struct ast_cc_agent *sig_pri_find_cc_agent_by_cc_id(struct sig_pri_span *pri, long cc_id)
{
	struct sig_pri_cc_agent_prv finder = {
		.pri = pri,
		.cc_id = cc_id,
	};

	return ast_cc_agent_callback(0, sig_pri_cc_agent_cmp_cc_id, &finder,
		sig_pri_cc_type_name);
}
#endif	/* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Compare the CC monitor instance by libpri cc_id.
 * \since 1.8
 *
 * \param obj pointer to the (user-defined part) of an object.
 * \param arg callback argument from ao2_callback()
 * \param flags flags from ao2_callback()
 *
 * \return values are a combination of enum _cb_results.
 */
static int sig_pri_cc_monitor_cmp_cc_id(void *obj, void *arg, int flags)
{
	struct sig_pri_cc_monitor_instance *monitor_1 = obj;
	struct sig_pri_cc_monitor_instance *monitor_2 = arg;

	return (monitor_1->pri == monitor_2->pri
		&& monitor_1->cc_id == monitor_2->cc_id) ? CMP_MATCH | CMP_STOP : 0;
}
#endif	/* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Find the CC monitor instance by libpri cc_id.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param cc_id CC record ID to find.
 *
 * \note
 * Since monitor_instances are refcounted, and this function returns
 * a reference to the instance, it is imperative that you decrement
 * the refcount of the instance once you have finished using it.
 *
 * \retval monitor_instance on success.
 * \retval NULL not found.
 */
static struct sig_pri_cc_monitor_instance *sig_pri_find_cc_monitor_by_cc_id(struct sig_pri_span *pri, long cc_id)
{
	struct sig_pri_cc_monitor_instance finder = {
		.pri = pri,
		.cc_id = cc_id,
	};

	return ao2_callback(sig_pri_cc_monitors, 0, sig_pri_cc_monitor_cmp_cc_id, &finder);
}
#endif	/* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Destroy the given monitor instance.
 * \since 1.8
 *
 * \param data Monitor instance to destroy.
 *
 * \return Nothing
 */
static void sig_pri_cc_monitor_instance_destroy(void *data)
{
	struct sig_pri_cc_monitor_instance *monitor_instance = data;

	if (monitor_instance->cc_id != -1) {
		ast_mutex_lock(&monitor_instance->pri->lock);
		pri_cc_cancel(monitor_instance->pri->pri, monitor_instance->cc_id);
		ast_mutex_unlock(&monitor_instance->pri->lock);
	}
	sig_pri_callbacks.module_unref();
}
#endif	/* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Construct a new monitor instance.
 * \since 1.8
 *
 * \param core_id CC core ID.
 * \param pri PRI span control structure.
 * \param cc_id CC record ID.
 * \param device_name Name of device (Asterisk channel name less sequence number).
 *
 * \note
 * Since monitor_instances are refcounted, and this function returns
 * a reference to the instance, it is imperative that you decrement
 * the refcount of the instance once you have finished using it.
 *
 * \retval monitor_instance on success.
 * \retval NULL on error.
 */
static struct sig_pri_cc_monitor_instance *sig_pri_cc_monitor_instance_init(int core_id, struct sig_pri_span *pri, long cc_id, const char *device_name)
{
	struct sig_pri_cc_monitor_instance *monitor_instance;

	if (!sig_pri_callbacks.module_ref || !sig_pri_callbacks.module_unref) {
		return NULL;
	}

	monitor_instance = ao2_alloc(sizeof(*monitor_instance) + strlen(device_name),
		sig_pri_cc_monitor_instance_destroy);
	if (!monitor_instance) {
		return NULL;
	}

	monitor_instance->cc_id = cc_id;
	monitor_instance->pri = pri;
	monitor_instance->core_id = core_id;
	strcpy(monitor_instance->name, device_name);

	sig_pri_callbacks.module_ref();

	ao2_link(sig_pri_cc_monitors, monitor_instance);
	return monitor_instance;
}
#endif	/* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Announce to the CC core that protocol CC monitor is available for this call.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param chanpos Channel position in the span.
 * \param cc_id CC record ID.
 * \param service CCBS/CCNR indication.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 * \note Assumes the sig_pri_lock_owner(pri, chanpos) is already obtained.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int sig_pri_cc_available(struct sig_pri_span *pri, int chanpos, long cc_id, enum ast_cc_service_type service)
{
	struct sig_pri_chan *pvt;
	struct ast_cc_config_params *cc_params;
	struct sig_pri_cc_monitor_instance *monitor;
	enum ast_cc_monitor_policies monitor_policy;
	int core_id;
	int res;
	char device_name[AST_CHANNEL_NAME];
	char dialstring[AST_CHANNEL_NAME];

	pvt = pri->pvts[chanpos];

	core_id = ast_cc_get_current_core_id(pvt->owner);
	if (core_id == -1) {
		return -1;
	}

	cc_params = ast_channel_get_cc_config_params(pvt->owner);
	if (!cc_params) {
		return -1;
	}

	res = -1;
	monitor_policy = ast_get_cc_monitor_policy(cc_params);
	switch (monitor_policy) {
	case AST_CC_MONITOR_NEVER:
		/* CCSS is not enabled. */
		break;
	case AST_CC_MONITOR_NATIVE:
	case AST_CC_MONITOR_ALWAYS:
		/*
		 * If it is AST_CC_MONITOR_ALWAYS and native fails we will attempt the fallback
		 * later in the call to sig_pri_cc_generic_check().
		 */
		ast_channel_get_device_name(pvt->owner, device_name, sizeof(device_name));
		sig_pri_make_cc_dialstring(pvt, dialstring, sizeof(dialstring));
		monitor = sig_pri_cc_monitor_instance_init(core_id, pri, cc_id, device_name);
		if (!monitor) {
			break;
		}
		res = ast_queue_cc_frame(pvt->owner, sig_pri_cc_type_name, dialstring, service,
			monitor);
		if (res) {
			monitor->cc_id = -1;
			ao2_unlink(sig_pri_cc_monitors, monitor);
			ao2_ref(monitor, -1);
		}
		break;
	case AST_CC_MONITOR_GENERIC:
		ast_queue_cc_frame(pvt->owner, AST_CC_GENERIC_MONITOR_TYPE,
			sig_pri_get_orig_dialstring(pvt), service, NULL);
		/* Say it failed to force caller to cancel native CC. */
		break;
	}
	return res;
}
#endif	/* defined(HAVE_PRI_CCSS) */

/*!
 * \internal
 * \brief Check if generic CC monitor is needed and request it.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param chanpos Channel position in the span.
 * \param service CCBS/CCNR indication.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_cc_generic_check(struct sig_pri_span *pri, int chanpos, enum ast_cc_service_type service)
{
	struct ast_channel *owner;
	struct ast_cc_config_params *cc_params;
#if defined(HAVE_PRI_CCSS)
	struct ast_cc_monitor *monitor;
	char device_name[AST_CHANNEL_NAME];
#endif	/* defined(HAVE_PRI_CCSS) */
	enum ast_cc_monitor_policies monitor_policy;
	int core_id;

	if (!pri->pvts[chanpos]->outgoing) {
		/* This is not an outgoing call so it cannot be CC monitor. */
		return;
	}

	sig_pri_lock_owner(pri, chanpos);
	owner = pri->pvts[chanpos]->owner;
	if (!owner) {
		return;
	}
	core_id = ast_cc_get_current_core_id(owner);
	if (core_id == -1) {
		/* No CC core setup */
		goto done;
	}

	cc_params = ast_channel_get_cc_config_params(owner);
	if (!cc_params) {
		/* Could not get CC config parameters. */
		goto done;
	}

#if defined(HAVE_PRI_CCSS)
	ast_channel_get_device_name(owner, device_name, sizeof(device_name));
	monitor = ast_cc_get_monitor_by_recall_core_id(core_id, device_name);
	if (monitor) {
		/* CC monitor is already present so no need for generic CC. */
		ao2_ref(monitor, -1);
		goto done;
	}
#endif	/* defined(HAVE_PRI_CCSS) */

	monitor_policy = ast_get_cc_monitor_policy(cc_params);
	switch (monitor_policy) {
	case AST_CC_MONITOR_NEVER:
		/* CCSS is not enabled. */
		break;
	case AST_CC_MONITOR_NATIVE:
		if (pri->sig == SIG_BRI_PTMP && pri->nodetype == PRI_NETWORK) {
			/* Request generic CC monitor. */
			ast_queue_cc_frame(owner, AST_CC_GENERIC_MONITOR_TYPE,
				sig_pri_get_orig_dialstring(pri->pvts[chanpos]), service, NULL);
		}
		break;
	case AST_CC_MONITOR_ALWAYS:
		if (pri->sig == SIG_BRI_PTMP && pri->nodetype != PRI_NETWORK) {
			/*
			 * Cannot monitor PTMP TE side since this is not defined.
			 * We are playing the roll of a phone in this case and
			 * a phone cannot monitor a party over the network without
			 * protocol help.
			 */
			break;
		}
		/*
		 * We are either falling back or this is a PTMP NT span.
		 * Request generic CC monitor.
		 */
		ast_queue_cc_frame(owner, AST_CC_GENERIC_MONITOR_TYPE,
			sig_pri_get_orig_dialstring(pri->pvts[chanpos]), service, NULL);
		break;
	case AST_CC_MONITOR_GENERIC:
		if (pri->sig == SIG_BRI_PTMP && pri->nodetype == PRI_NETWORK) {
			/* Request generic CC monitor. */
			ast_queue_cc_frame(owner, AST_CC_GENERIC_MONITOR_TYPE,
				sig_pri_get_orig_dialstring(pri->pvts[chanpos]), service, NULL);
		}
		break;
	}

done:
	ast_channel_unlock(owner);
}

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief The CC link canceled the CC instance.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param cc_id CC record ID.
 * \param is_agent TRUE if the cc_id is for an agent.
 *
 * \return Nothing
 */
static void sig_pri_cc_link_canceled(struct sig_pri_span *pri, long cc_id, int is_agent)
{
	if (is_agent) {
		struct ast_cc_agent *agent;

		agent = sig_pri_find_cc_agent_by_cc_id(pri, cc_id);
		if (!agent) {
			return;
		}
		ast_cc_failed(agent->core_id, "%s agent got canceled by link",
			sig_pri_cc_type_name);
		ao2_ref(agent, -1);
	} else {
		struct sig_pri_cc_monitor_instance *monitor;

		monitor = sig_pri_find_cc_monitor_by_cc_id(pri, cc_id);
		if (!monitor) {
			return;
		}
		monitor->cc_id = -1;
		ast_cc_monitor_failed(monitor->core_id, monitor->name,
			"%s monitor got canceled by link", sig_pri_cc_type_name);
		ao2_ref(monitor, -1);
	}
}
#endif	/* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Convert ast_aoc_charged_item to PRI_AOC_CHARGED_ITEM .
 * \since 1.8
 *
 * \param value Value to convert to string.
 *
 * \return PRI_AOC_CHARGED_ITEM
 */
static enum PRI_AOC_CHARGED_ITEM sig_pri_aoc_charged_item_to_pri(enum PRI_AOC_CHARGED_ITEM value)
{
	switch (value) {
	case AST_AOC_CHARGED_ITEM_NA:
		return PRI_AOC_CHARGED_ITEM_NOT_AVAILABLE;
	case AST_AOC_CHARGED_ITEM_SPECIAL_ARRANGEMENT:
		return PRI_AOC_CHARGED_ITEM_SPECIAL_ARRANGEMENT;
	case AST_AOC_CHARGED_ITEM_BASIC_COMMUNICATION:
		return PRI_AOC_CHARGED_ITEM_BASIC_COMMUNICATION;
	case AST_AOC_CHARGED_ITEM_CALL_ATTEMPT:
		return PRI_AOC_CHARGED_ITEM_CALL_ATTEMPT;
	case AST_AOC_CHARGED_ITEM_CALL_SETUP:
		return PRI_AOC_CHARGED_ITEM_CALL_SETUP;
	case AST_AOC_CHARGED_ITEM_USER_USER_INFO:
		return PRI_AOC_CHARGED_ITEM_USER_USER_INFO;
	case AST_AOC_CHARGED_ITEM_SUPPLEMENTARY_SERVICE:
		return PRI_AOC_CHARGED_ITEM_SUPPLEMENTARY_SERVICE;
	}
	return PRI_AOC_CHARGED_ITEM_NOT_AVAILABLE;
}
#endif	/* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Convert PRI_AOC_CHARGED_ITEM to ast_aoc_charged_item.
 * \since 1.8
 *
 * \param value Value to convert to string.
 *
 * \return ast_aoc_charged_item
 */
static enum ast_aoc_s_charged_item sig_pri_aoc_charged_item_to_ast(enum PRI_AOC_CHARGED_ITEM value)
{
	switch (value) {
	case PRI_AOC_CHARGED_ITEM_NOT_AVAILABLE:
		return AST_AOC_CHARGED_ITEM_NA;
	case PRI_AOC_CHARGED_ITEM_SPECIAL_ARRANGEMENT:
		return AST_AOC_CHARGED_ITEM_SPECIAL_ARRANGEMENT;
	case PRI_AOC_CHARGED_ITEM_BASIC_COMMUNICATION:
		return AST_AOC_CHARGED_ITEM_BASIC_COMMUNICATION;
	case PRI_AOC_CHARGED_ITEM_CALL_ATTEMPT:
		return AST_AOC_CHARGED_ITEM_CALL_ATTEMPT;
	case PRI_AOC_CHARGED_ITEM_CALL_SETUP:
		return AST_AOC_CHARGED_ITEM_CALL_SETUP;
	case PRI_AOC_CHARGED_ITEM_USER_USER_INFO:
		return AST_AOC_CHARGED_ITEM_USER_USER_INFO;
	case PRI_AOC_CHARGED_ITEM_SUPPLEMENTARY_SERVICE:
		return AST_AOC_CHARGED_ITEM_SUPPLEMENTARY_SERVICE;
	}
	return AST_AOC_CHARGED_ITEM_NA;
}
#endif	/* defined(HAVE_PRI_AOC_EVENTS) */