sig_pri.c

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2009, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief PRI signaling module
 *
 * \author Matthew Fredrickson <creslin@digium.com>
 */

/*** MODULEINFO
	<support_level>core</support_level>
 ***/

#include "asterisk.h"

#ifdef HAVE_PRI

#include <errno.h>
#include <ctype.h>
#include <signal.h>

#include "asterisk/utils.h"
#include "asterisk/options.h"
#include "asterisk/pbx.h"
#include "asterisk/app.h"
#include "asterisk/file.h"
#include "asterisk/callerid.h"
#include "asterisk/say.h"
#include "asterisk/manager.h"
#include "asterisk/astdb.h"
#include "asterisk/causes.h"
#include "asterisk/musiconhold.h"
#include "asterisk/cli.h"
#include "asterisk/transcap.h"
#include "asterisk/features.h"
#include "asterisk/aoc.h"

#include "sig_pri.h"
#ifndef PRI_EVENT_FACILITY
#error "Upgrade your libpri"
#endif

/*** DOCUMENTATION
 ***/


/* define this to send PRI user-user information elements */
#undef SUPPORT_USERUSER

/*!
 * Define to make always pick a channel if allowed.  Useful for
 * testing channel shifting.
 */
//#define ALWAYS_PICK_CHANNEL	1

/*!
 * Define to force a RESTART on a channel that returns a cause
 * code of PRI_CAUSE_REQUESTED_CHAN_UNAVAIL(44).  If the cause
 * is because of a stuck channel on the peer and the channel is
 * always the next channel we pick for an outgoing call then
 * this can help.
 */
#define FORCE_RESTART_UNAVAIL_CHANS		1

#if defined(HAVE_PRI_CCSS)
struct sig_pri_cc_agent_prv {
	/*! Asterisk span D channel control structure. */
	struct sig_pri_span *pri;
	/*! CC id value to use with libpri. -1 if invalid. */
	long cc_id;
	/*! TRUE if CC has been requested and we are waiting for the response. */
	unsigned char cc_request_response_pending;
};

struct sig_pri_cc_monitor_instance {
	/*! \brief Asterisk span D channel control structure. */
	struct sig_pri_span *pri;
	/*! CC id value to use with libpri. (-1 if already canceled). */
	long cc_id;
	/*! CC core id value. */
	int core_id;
	/*! Device name(Channel name less sequence number) */
	char name[1];
};

/*! Upper level agent/monitor type name. */
static const char *sig_pri_cc_type_name;
/*! Container of sig_pri monitor instances. */
static struct ao2_container *sig_pri_cc_monitors;
#endif	/* defined(HAVE_PRI_CCSS) */

static int pri_matchdigittimeout = 3000;

static int pri_gendigittimeout = 8000;

#define DCHAN_NOTINALARM  (1 << 0)
#define DCHAN_UP          (1 << 1)

/* Defines to help decode the encoded event channel id. */
#define PRI_CHANNEL(p)	((p) & 0xff)
#define PRI_SPAN(p)		(((p) >> 8) & 0xff)
#define PRI_EXPLICIT	(1 << 16)
#define PRI_CIS_CALL	(1 << 17)	/* Call is using the D channel only. */
#define PRI_HELD_CALL	(1 << 18)


#define DCHAN_AVAILABLE	(DCHAN_NOTINALARM | DCHAN_UP)

static int pri_active_dchan_index(struct sig_pri_span *pri);

static const char *sig_pri_call_level2str(enum sig_pri_call_level level)
{
	switch (level) {
	case SIG_PRI_CALL_LEVEL_IDLE:
		return "Idle";
	case SIG_PRI_CALL_LEVEL_SETUP:
		return "Setup";
	case SIG_PRI_CALL_LEVEL_OVERLAP:
		return "Overlap";
	case SIG_PRI_CALL_LEVEL_PROCEEDING:
		return "Proceeding";
	case SIG_PRI_CALL_LEVEL_ALERTING:
		return "Alerting";
	case SIG_PRI_CALL_LEVEL_DEFER_DIAL:
		return "DeferDial";
	case SIG_PRI_CALL_LEVEL_CONNECT:
		return "Connect";
	}
	return "Unknown";
}

static inline void pri_rel(struct sig_pri_span *pri)
{
	ast_mutex_unlock(&pri->lock);
}

static unsigned int PVT_TO_CHANNEL(struct sig_pri_chan *p)
{
	int res = (((p)->prioffset) | ((p)->logicalspan << 8) | (p->mastertrunkgroup ? PRI_EXPLICIT : 0));
	ast_debug(5, "prioffset: %d mastertrunkgroup: %d logicalspan: %d result: %d\n",
		p->prioffset, p->mastertrunkgroup, p->logicalspan, res);

	return res;
}

static void sig_pri_handle_dchan_exception(struct sig_pri_span *pri, int index)
{
	if (sig_pri_callbacks.handle_dchan_exception) {
		sig_pri_callbacks.handle_dchan_exception(pri, index);
	}
}

static void sig_pri_set_dialing(struct sig_pri_chan *p, int is_dialing)
{
	if (sig_pri_callbacks.set_dialing) {
		sig_pri_callbacks.set_dialing(p->chan_pvt, is_dialing);
	}
}

static void sig_pri_set_digital(struct sig_pri_chan *p, int is_digital)
{
	p->digital = is_digital;
	if (sig_pri_callbacks.set_digital) {
		sig_pri_callbacks.set_digital(p->chan_pvt, is_digital);
	}
}

static void sig_pri_set_outgoing(struct sig_pri_chan *p, int is_outgoing)
{
	p->outgoing = is_outgoing;
	if (sig_pri_callbacks.set_outgoing) {
		sig_pri_callbacks.set_outgoing(p->chan_pvt, is_outgoing);
	}
}

void sig_pri_set_alarm(struct sig_pri_chan *p, int in_alarm)
{
	if (sig_pri_is_alarm_ignored(p->pri)) {
		/* Always set not in alarm */
		in_alarm = 0;
	}

	/*
	 * Clear the channel restart state when the channel alarm
	 * changes to prevent the state from getting stuck when the link
	 * goes down.
	 */
	p->resetting = SIG_PRI_RESET_IDLE;

	p->inalarm = in_alarm;
	if (sig_pri_callbacks.set_alarm) {
		sig_pri_callbacks.set_alarm(p->chan_pvt, in_alarm);
	}
}

static const char *sig_pri_get_orig_dialstring(struct sig_pri_chan *p)
{
	if (sig_pri_callbacks.get_orig_dialstring) {
		return sig_pri_callbacks.get_orig_dialstring(p->chan_pvt);
	}
	ast_log(LOG_ERROR, "get_orig_dialstring callback not defined\n");
	return "";
}

#if defined(HAVE_PRI_CCSS)
static void sig_pri_make_cc_dialstring(struct sig_pri_chan *p, char *buf, size_t buf_size)
{
	if (sig_pri_callbacks.make_cc_dialstring) {
		sig_pri_callbacks.make_cc_dialstring(p->chan_pvt, buf, buf_size);
	} else {
		ast_log(LOG_ERROR, "make_cc_dialstring callback not defined\n");
		buf[0] = '\0';
	}
}
#endif	/* defined(HAVE_PRI_CCSS) */

static void sig_pri_dial_digits(struct sig_pri_chan *p, const char *dial_string)
{
	if (sig_pri_callbacks.dial_digits) {
		sig_pri_callbacks.dial_digits(p->chan_pvt, dial_string);
	}
}

/*!
 * \internal
 * \brief Reevaluate the PRI span device state.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 *
 * \return Nothing
 *
 * \note Assumes the pri->lock is already obtained.
 */
static void sig_pri_span_devstate_changed(struct sig_pri_span *pri)
{
	if (sig_pri_callbacks.update_span_devstate) {
		sig_pri_callbacks.update_span_devstate(pri);
	}
}

/*!
 * \internal
 * \brief Set the caller id information in the parent module.
 * \since 1.8
 *
 * \param p sig_pri channel structure.
 *
 * \return Nothing
 */
static void sig_pri_set_caller_id(struct sig_pri_chan *p)
{
	struct ast_party_caller caller;

	if (sig_pri_callbacks.set_callerid) {
		ast_party_caller_init(&caller);

		caller.id.name.str = p->cid_name;
		caller.id.name.presentation = p->callingpres;
		caller.id.name.valid = 1;

		caller.id.number.str = p->cid_num;
		caller.id.number.plan = p->cid_ton;
		caller.id.number.presentation = p->callingpres;
		caller.id.number.valid = 1;

		if (!ast_strlen_zero(p->cid_subaddr)) {
			caller.id.subaddress.valid = 1;
			//caller.id.subaddress.type = 0;/* nsap */
			//caller.id.subaddress.odd_even_indicator = 0;
			caller.id.subaddress.str = p->cid_subaddr;
		}
		caller.id.tag = p->user_tag;

		caller.ani.number.str = p->cid_ani;
		//caller.ani.number.plan = p->xxx;
		//caller.ani.number.presentation = p->xxx;
		caller.ani.number.valid = 1;

		caller.ani2 = p->cid_ani2;
		sig_pri_callbacks.set_callerid(p->chan_pvt, &caller);
	}
}

/*!
 * \internal
 * \brief Set the Dialed Number Identifier.
 * \since 1.8
 *
 * \param p sig_pri channel structure.
 * \param dnid Dialed Number Identifier string.
 *
 * \return Nothing
 */
static void sig_pri_set_dnid(struct sig_pri_chan *p, const char *dnid)
{
	if (sig_pri_callbacks.set_dnid) {
		sig_pri_callbacks.set_dnid(p->chan_pvt, dnid);
	}
}

/*!
 * \internal
 * \brief Set the Redirecting Directory Number Information Service (RDNIS).
 * \since 1.8
 *
 * \param p sig_pri channel structure.
 * \param rdnis Redirecting Directory Number Information Service (RDNIS) string.
 *
 * \return Nothing
 */
static void sig_pri_set_rdnis(struct sig_pri_chan *p, const char *rdnis)
{
	if (sig_pri_callbacks.set_rdnis) {
		sig_pri_callbacks.set_rdnis(p->chan_pvt, rdnis);
	}
}

static void sig_pri_unlock_private(struct sig_pri_chan *p)
{
	if (sig_pri_callbacks.unlock_private) {
		sig_pri_callbacks.unlock_private(p->chan_pvt);
	}
}

static void sig_pri_lock_private(struct sig_pri_chan *p)
{
	if (sig_pri_callbacks.lock_private) {
		sig_pri_callbacks.lock_private(p->chan_pvt);
	}
}

static void sig_pri_deadlock_avoidance_private(struct sig_pri_chan *p)
{
	if (sig_pri_callbacks.deadlock_avoidance_private) {
		sig_pri_callbacks.deadlock_avoidance_private(p->chan_pvt);
	} else {
		/* Fallback to the old way if callback not present. */
		sig_pri_unlock_private(p);
		sched_yield();
		sig_pri_lock_private(p);
	}
}

static void pri_grab(struct sig_pri_chan *p, struct sig_pri_span *pri)
{
	/* Grab the lock first */
	while (ast_mutex_trylock(&pri->lock)) {
		/* Avoid deadlock */
		sig_pri_deadlock_avoidance_private(p);
	}
	/* Then break the poll */
	if (pri->master != AST_PTHREADT_NULL) {
		pthread_kill(pri->master, SIGURG);
	}
}

/*!
 * \internal
 * \brief Convert PRI redirecting reason to asterisk version.
 * \since 1.8
 *
 * \param pri_reason PRI redirecting reason.
 *
 * \return Equivalent asterisk redirecting reason value.
 */
static enum AST_REDIRECTING_REASON pri_to_ast_reason(int pri_reason)
{
	enum AST_REDIRECTING_REASON ast_reason;

	switch (pri_reason) {
	case PRI_REDIR_FORWARD_ON_BUSY:
		ast_reason = AST_REDIRECTING_REASON_USER_BUSY;
		break;
	case PRI_REDIR_FORWARD_ON_NO_REPLY:
		ast_reason = AST_REDIRECTING_REASON_NO_ANSWER;
		break;
	case PRI_REDIR_DEFLECTION:
		ast_reason = AST_REDIRECTING_REASON_DEFLECTION;
		break;
	case PRI_REDIR_UNCONDITIONAL:
		ast_reason = AST_REDIRECTING_REASON_UNCONDITIONAL;
		break;
	case PRI_REDIR_UNKNOWN:
	default:
		ast_reason = AST_REDIRECTING_REASON_UNKNOWN;
		break;
	}

	return ast_reason;
}

/*!
 * \internal
 * \brief Convert asterisk redirecting reason to PRI version.
 * \since 1.8
 *
 * \param ast_reason Asterisk redirecting reason.
 *
 * \return Equivalent PRI redirecting reason value.
 */
static int ast_to_pri_reason(enum AST_REDIRECTING_REASON ast_reason)
{
	int pri_reason;

	switch (ast_reason) {
	case AST_REDIRECTING_REASON_USER_BUSY:
		pri_reason = PRI_REDIR_FORWARD_ON_BUSY;
		break;
	case AST_REDIRECTING_REASON_NO_ANSWER:
		pri_reason = PRI_REDIR_FORWARD_ON_NO_REPLY;
		break;
	case AST_REDIRECTING_REASON_UNCONDITIONAL:
		pri_reason = PRI_REDIR_UNCONDITIONAL;
		break;
	case AST_REDIRECTING_REASON_DEFLECTION:
		pri_reason = PRI_REDIR_DEFLECTION;
		break;
	case AST_REDIRECTING_REASON_UNKNOWN:
	default:
		pri_reason = PRI_REDIR_UNKNOWN;
		break;
	}

	return pri_reason;
}

/*!
 * \internal
 * \brief Convert PRI number presentation to asterisk version.
 * \since 1.8
 *
 * \param pri_presentation PRI number presentation.
 *
 * \return Equivalent asterisk number presentation value.
 */
static int pri_to_ast_presentation(int pri_presentation)
{
	int ast_presentation;

	switch (pri_presentation) {
	case PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_UNSCREENED:
		ast_presentation = AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_UNSCREENED;
		break;
	case PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_PASSED_SCREEN:
		ast_presentation = AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_PASSED_SCREEN;
		break;
	case PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_FAILED_SCREEN:
		ast_presentation = AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_FAILED_SCREEN;
		break;
	case PRI_PRES_ALLOWED | PRI_PRES_NETWORK_NUMBER:
		ast_presentation = AST_PRES_ALLOWED | AST_PRES_NETWORK_NUMBER;
		break;

	case PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_UNSCREENED:
		ast_presentation = AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_UNSCREENED;
		break;
	case PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_PASSED_SCREEN:
		ast_presentation = AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_PASSED_SCREEN;
		break;
	case PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_FAILED_SCREEN:
		ast_presentation = AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_FAILED_SCREEN;
		break;
	case PRI_PRES_RESTRICTED | PRI_PRES_NETWORK_NUMBER:
		ast_presentation = AST_PRES_RESTRICTED | AST_PRES_NETWORK_NUMBER;
		break;

	case PRI_PRES_UNAVAILABLE | PRI_PRES_USER_NUMBER_UNSCREENED:
	case PRI_PRES_UNAVAILABLE | PRI_PRES_USER_NUMBER_PASSED_SCREEN:
	case PRI_PRES_UNAVAILABLE | PRI_PRES_USER_NUMBER_FAILED_SCREEN:
	case PRI_PRES_UNAVAILABLE | PRI_PRES_NETWORK_NUMBER:
		ast_presentation = AST_PRES_NUMBER_NOT_AVAILABLE;
		break;

	default:
		ast_presentation = AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_UNSCREENED;
		break;
	}

	return ast_presentation;
}

/*!
 * \internal
 * \brief Convert asterisk number presentation to PRI version.
 * \since 1.8
 *
 * \param ast_presentation Asterisk number presentation.
 *
 * \return Equivalent PRI number presentation value.
 */
static int ast_to_pri_presentation(int ast_presentation)
{
	int pri_presentation;

	switch (ast_presentation) {
	case AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_UNSCREENED:
		pri_presentation = PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_UNSCREENED;
		break;
	case AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_PASSED_SCREEN:
		pri_presentation = PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_PASSED_SCREEN;
		break;
	case AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_FAILED_SCREEN:
		pri_presentation = PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_FAILED_SCREEN;
		break;
	case AST_PRES_ALLOWED | AST_PRES_NETWORK_NUMBER:
		pri_presentation = PRI_PRES_ALLOWED | PRI_PRES_NETWORK_NUMBER;
		break;

	case AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_UNSCREENED:
		pri_presentation = PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_UNSCREENED;
		break;
	case AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_PASSED_SCREEN:
		pri_presentation = PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_PASSED_SCREEN;
		break;
	case AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_FAILED_SCREEN:
		pri_presentation = PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_FAILED_SCREEN;
		break;
	case AST_PRES_RESTRICTED | AST_PRES_NETWORK_NUMBER:
		pri_presentation = PRI_PRES_RESTRICTED | PRI_PRES_NETWORK_NUMBER;
		break;

	case AST_PRES_UNAVAILABLE | AST_PRES_USER_NUMBER_UNSCREENED:
	case AST_PRES_UNAVAILABLE | AST_PRES_USER_NUMBER_PASSED_SCREEN:
	case AST_PRES_UNAVAILABLE | AST_PRES_USER_NUMBER_FAILED_SCREEN:
	case AST_PRES_UNAVAILABLE | AST_PRES_NETWORK_NUMBER:
		pri_presentation = PRES_NUMBER_NOT_AVAILABLE;
		break;

	default:
		pri_presentation = PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_UNSCREENED;
		break;
	}

	return pri_presentation;
}

/*!
 * \internal
 * \brief Convert PRI name char_set to asterisk version.
 * \since 1.8
 *
 * \param pri_char_set PRI name char_set.
 *
 * \return Equivalent asterisk name char_set value.
 */
static enum AST_PARTY_CHAR_SET pri_to_ast_char_set(int pri_char_set)
{
	enum AST_PARTY_CHAR_SET ast_char_set;

	switch (pri_char_set) {
	default:
	case PRI_CHAR_SET_UNKNOWN:
		ast_char_set = AST_PARTY_CHAR_SET_UNKNOWN;
		break;
	case PRI_CHAR_SET_ISO8859_1:
		ast_char_set = AST_PARTY_CHAR_SET_ISO8859_1;
		break;
	case PRI_CHAR_SET_WITHDRAWN:
		ast_char_set = AST_PARTY_CHAR_SET_WITHDRAWN;
		break;
	case PRI_CHAR_SET_ISO8859_2:
		ast_char_set = AST_PARTY_CHAR_SET_ISO8859_2;
		break;
	case PRI_CHAR_SET_ISO8859_3:
		ast_char_set = AST_PARTY_CHAR_SET_ISO8859_3;
		break;
	case PRI_CHAR_SET_ISO8859_4:
		ast_char_set = AST_PARTY_CHAR_SET_ISO8859_4;
		break;
	case PRI_CHAR_SET_ISO8859_5:
		ast_char_set = AST_PARTY_CHAR_SET_ISO8859_5;
		break;
	case PRI_CHAR_SET_ISO8859_7:
		ast_char_set = AST_PARTY_CHAR_SET_ISO8859_7;
		break;
	case PRI_CHAR_SET_ISO10646_BMPSTRING:
		ast_char_set = AST_PARTY_CHAR_SET_ISO10646_BMPSTRING;
		break;
	case PRI_CHAR_SET_ISO10646_UTF_8STRING:
		ast_char_set = AST_PARTY_CHAR_SET_ISO10646_UTF_8STRING;
		break;
	}

	return ast_char_set;
}

/*!
 * \internal
 * \brief Convert asterisk name char_set to PRI version.
 * \since 1.8
 *
 * \param ast_char_set Asterisk name char_set.
 *
 * \return Equivalent PRI name char_set value.
 */
static int ast_to_pri_char_set(enum AST_PARTY_CHAR_SET ast_char_set)
{
	int pri_char_set;

	switch (ast_char_set) {
	default:
	case AST_PARTY_CHAR_SET_UNKNOWN:
		pri_char_set = PRI_CHAR_SET_UNKNOWN;
		break;
	case AST_PARTY_CHAR_SET_ISO8859_1:
		pri_char_set = PRI_CHAR_SET_ISO8859_1;
		break;
	case AST_PARTY_CHAR_SET_WITHDRAWN:
		pri_char_set = PRI_CHAR_SET_WITHDRAWN;
		break;
	case AST_PARTY_CHAR_SET_ISO8859_2:
		pri_char_set = PRI_CHAR_SET_ISO8859_2;
		break;
	case AST_PARTY_CHAR_SET_ISO8859_3:
		pri_char_set = PRI_CHAR_SET_ISO8859_3;
		break;
	case AST_PARTY_CHAR_SET_ISO8859_4:
		pri_char_set = PRI_CHAR_SET_ISO8859_4;
		break;
	case AST_PARTY_CHAR_SET_ISO8859_5:
		pri_char_set = PRI_CHAR_SET_ISO8859_5;
		break;
	case AST_PARTY_CHAR_SET_ISO8859_7:
		pri_char_set = PRI_CHAR_SET_ISO8859_7;
		break;
	case AST_PARTY_CHAR_SET_ISO10646_BMPSTRING:
		pri_char_set = PRI_CHAR_SET_ISO10646_BMPSTRING;
		break;
	case AST_PARTY_CHAR_SET_ISO10646_UTF_8STRING:
		pri_char_set = PRI_CHAR_SET_ISO10646_UTF_8STRING;
		break;
	}

	return pri_char_set;
}

#if defined(HAVE_PRI_SUBADDR)
/*!
 * \internal
 * \brief Fill in the asterisk party subaddress from the given PRI party subaddress.
 * \since 1.8
 *
 * \param ast_subaddress Asterisk party subaddress structure.
 * \param pri_subaddress PRI party subaddress structure.
 *
 * \return Nothing
 *
 */
static void sig_pri_set_subaddress(struct ast_party_subaddress *ast_subaddress, const struct pri_party_subaddress *pri_subaddress)
{
	char *cnum, *ptr;
	int x, len;

	if (ast_subaddress->str) {
		ast_free(ast_subaddress->str);
	}
	if (pri_subaddress->length <= 0) {
		ast_party_subaddress_init(ast_subaddress);
		return;
	}

	if (!pri_subaddress->type) {
		/* NSAP */
		ast_subaddress->str = ast_strdup((char *) pri_subaddress->data);
	} else {
		/* User Specified */
		if (!(cnum = ast_malloc(2 * pri_subaddress->length + 1))) {
			ast_party_subaddress_init(ast_subaddress);
			return;
		}

		ptr = cnum;
		len = pri_subaddress->length - 1; /* -1 account for zero based indexing */
		for (x = 0; x < len; ++x) {
			ptr += sprintf(ptr, "%02x", pri_subaddress->data[x]);
		}

		if (pri_subaddress->odd_even_indicator) {
			/* ODD */
			sprintf(ptr, "%01x", (pri_subaddress->data[len]) >> 4);
		} else {
			/* EVEN */
			sprintf(ptr, "%02x", pri_subaddress->data[len]);
		}
		ast_subaddress->str = cnum;
	}
	ast_subaddress->type = pri_subaddress->type;
	ast_subaddress->odd_even_indicator = pri_subaddress->odd_even_indicator;
	ast_subaddress->valid = 1;
}
#endif	/* defined(HAVE_PRI_SUBADDR) */

#if defined(HAVE_PRI_SUBADDR)
static unsigned char ast_pri_pack_hex_char(char c)
{
	unsigned char res;

	if (c < '0') {
		res = 0;
	} else if (c < ('9' + 1)) {
		res = c - '0';
	} else if (c < 'A') {
		res = 0;
	} else if (c < ('F' + 1)) {
		res = c - 'A' + 10;
	} else if (c < 'a') {
		res = 0;
	} else if (c < ('f' + 1)) {
		res = c - 'a' + 10;
	} else {
		res = 0;
	}
	return res;
}
#endif	/* defined(HAVE_PRI_SUBADDR) */

#if defined(HAVE_PRI_SUBADDR)
/*!
 * \internal
 * \brief Convert a null terminated hexadecimal string to a packed hex byte array.
 * \details left justified, with 0 padding if odd length.
 * \since 1.8
 *
 * \param dst pointer to packed byte array.
 * \param src pointer to null terminated hexadecimal string.
 * \param maxlen destination array size.
 *
 * \return Length of byte array
 *
 * \note The dst is not an ASCIIz string.
 * \note The src is an ASCIIz hex string.
 */
static int ast_pri_pack_hex_string(unsigned char *dst, char *src, int maxlen)
{
	int res = 0;
	int len = strlen(src);

	if (len > (2 * maxlen)) {
		len = 2 * maxlen;
	}

	res = len / 2 + len % 2;

	while (len > 1) {
		*dst = ast_pri_pack_hex_char(*src) << 4;
		src++;
		*dst |= ast_pri_pack_hex_char(*src);
		dst++, src++;
		len -= 2;
	}
	if (len) { /* 1 left */
		*dst = ast_pri_pack_hex_char(*src) << 4;
	}
	return res;
}
#endif	/* defined(HAVE_PRI_SUBADDR) */

#if defined(HAVE_PRI_SUBADDR)
/*!
 * \internal
 * \brief Fill in the PRI party subaddress from the given asterisk party subaddress.
 * \since 1.8
 *
 * \param pri_subaddress PRI party subaddress structure.
 * \param ast_subaddress Asterisk party subaddress structure.
 *
 * \return Nothing
 *
 * \note Assumes that pri_subaddress has been previously memset to zero.
 */
static void sig_pri_party_subaddress_from_ast(struct pri_party_subaddress *pri_subaddress, const struct ast_party_subaddress *ast_subaddress)
{
	if (ast_subaddress->valid && !ast_strlen_zero(ast_subaddress->str)) {
		pri_subaddress->type = ast_subaddress->type;
		if (!ast_subaddress->type) {
			/* 0 = NSAP */
			ast_copy_string((char *) pri_subaddress->data, ast_subaddress->str,
				sizeof(pri_subaddress->data));
			pri_subaddress->length = strlen((char *) pri_subaddress->data);
			pri_subaddress->odd_even_indicator = 0;
			pri_subaddress->valid = 1;
		} else {
			/* 2 = User Specified */
			/*
			 * Copy HexString to packed HexData,
			 * if odd length then right pad trailing byte with 0
			 */
			int length = ast_pri_pack_hex_string(pri_subaddress->data,
				ast_subaddress->str, sizeof(pri_subaddress->data));

			pri_subaddress->length = length; /* packed data length */

			length = strlen(ast_subaddress->str);
			if (length > 2 * sizeof(pri_subaddress->data)) {
				pri_subaddress->odd_even_indicator = 0;
			} else {
				pri_subaddress->odd_even_indicator = (length & 1);
			}
			pri_subaddress->valid = 1;
		}
	}
}
#endif	/* defined(HAVE_PRI_SUBADDR) */

/*!
 * \internal
 * \brief Fill in the PRI party name from the given asterisk party name.
 * \since 1.8
 *
 * \param pri_name PRI party name structure.
 * \param ast_name Asterisk party name structure.
 *
 * \return Nothing
 *
 * \note Assumes that pri_name has been previously memset to zero.
 */
static void sig_pri_party_name_from_ast(struct pri_party_name *pri_name, const struct ast_party_name *ast_name)
{
	if (!ast_name->valid) {
		return;
	}
	pri_name->valid = 1;
	pri_name->presentation = ast_to_pri_presentation(ast_name->presentation);
	pri_name->char_set = ast_to_pri_char_set(ast_name->char_set);
	if (!ast_strlen_zero(ast_name->str)) {
		ast_copy_string(pri_name->str, ast_name->str, sizeof(pri_name->str));
	}
}

/*!
 * \internal
 * \brief Fill in the PRI party number from the given asterisk party number.
 * \since 1.8
 *
 * \param pri_number PRI party number structure.
 * \param ast_number Asterisk party number structure.
 *
 * \return Nothing
 *
 * \note Assumes that pri_number has been previously memset to zero.
 */
static void sig_pri_party_number_from_ast(struct pri_party_number *pri_number, const struct ast_party_number *ast_number)
{
	if (!ast_number->valid) {
		return;
	}
	pri_number->valid = 1;
	pri_number->presentation = ast_to_pri_presentation(ast_number->presentation);
	pri_number->plan = ast_number->plan;
	if (!ast_strlen_zero(ast_number->str)) {
		ast_copy_string(pri_number->str, ast_number->str, sizeof(pri_number->str));
	}
}

/*!
 * \internal
 * \brief Fill in the PRI party id from the given asterisk party id.
 * \since 1.8
 *
 * \param pri_id PRI party id structure.
 * \param ast_id Asterisk party id structure.
 *
 * \return Nothing
 *
 * \note Assumes that pri_id has been previously memset to zero.
 */
static void sig_pri_party_id_from_ast(struct pri_party_id *pri_id, const struct ast_party_id *ast_id)
{
	sig_pri_party_name_from_ast(&pri_id->name, &ast_id->name);
	sig_pri_party_number_from_ast(&pri_id->number, &ast_id->number);
#if defined(HAVE_PRI_SUBADDR)
	sig_pri_party_subaddress_from_ast(&pri_id->subaddress, &ast_id->subaddress);
#endif	/* defined(HAVE_PRI_SUBADDR) */
}

/*!
 * \internal
 * \brief Update the PRI redirecting information for the current call.
 * \since 1.8
 *
 * \param pvt sig_pri private channel structure.
 * \param ast Asterisk channel
 *
 * \return Nothing
 *
 * \note Assumes that the PRI lock is already obtained.
 */
static void sig_pri_redirecting_update(struct sig_pri_chan *pvt, struct ast_channel *ast)
{
	struct pri_party_redirecting pri_redirecting;
	const struct ast_party_redirecting *ast_redirecting;
	struct ast_party_id redirecting_from = ast_channel_redirecting_effective_from(ast);
	struct ast_party_id redirecting_to = ast_channel_redirecting_effective_to(ast);
	struct ast_party_id redirecting_orig = ast_channel_redirecting_effective_orig(ast);

	memset(&pri_redirecting, 0, sizeof(pri_redirecting));
	ast_redirecting = ast_channel_redirecting(ast);
	sig_pri_party_id_from_ast(&pri_redirecting.from, &redirecting_from);
	sig_pri_party_id_from_ast(&pri_redirecting.to, &redirecting_to);
	sig_pri_party_id_from_ast(&pri_redirecting.orig_called, &redirecting_orig);
	pri_redirecting.count = ast_redirecting->count;
	pri_redirecting.orig_reason = ast_to_pri_reason(ast_redirecting->orig_reason);
	pri_redirecting.reason = ast_to_pri_reason(ast_redirecting->reason);

	pri_redirecting_update(pvt->pri->pri, pvt->call, &pri_redirecting);
}

/*!
 * \internal
 * \brief Reset DTMF detector.
 * \since 1.8
 *
 * \param p sig_pri channel structure.
 *
 * \return Nothing
 */
static void sig_pri_dsp_reset_and_flush_digits(struct sig_pri_chan *p)
{
	if (sig_pri_callbacks.dsp_reset_and_flush_digits) {
		sig_pri_callbacks.dsp_reset_and_flush_digits(p->chan_pvt);
	}
}

static int sig_pri_set_echocanceller(struct sig_pri_chan *p, int enable)
{
	if (sig_pri_callbacks.set_echocanceller) {
		return sig_pri_callbacks.set_echocanceller(p->chan_pvt, enable);
	} else {
		return -1;
	}
}

static void sig_pri_fixup_chans(struct sig_pri_chan *old_chan, struct sig_pri_chan *new_chan)
{
	if (sig_pri_callbacks.fixup_chans) {
		sig_pri_callbacks.fixup_chans(old_chan->chan_pvt, new_chan->chan_pvt);
	}
}

static int sig_pri_play_tone(struct sig_pri_chan *p, enum sig_pri_tone tone)
{
	if (sig_pri_callbacks.play_tone) {
		return sig_pri_callbacks.play_tone(p->chan_pvt, tone);
	} else {
		return -1;
	}
}

static struct ast_channel *sig_pri_new_ast_channel(struct sig_pri_chan *p, int state, int ulaw, int transfercapability, char *exten, const struct ast_channel *requestor)
{
	struct ast_channel *c;

	if (sig_pri_callbacks.new_ast_channel) {
		c = sig_pri_callbacks.new_ast_channel(p->chan_pvt, state, ulaw, exten, requestor);
	} else {
		return NULL;
	}
	if (!c) {
		return NULL;
	}

	if (!p->owner)
		p->owner = c;
	p->isidlecall = 0;
	p->alreadyhungup = 0;
	ast_channel_transfercapability_set(c, transfercapability);
	pbx_builtin_setvar_helper(c, "TRANSFERCAPABILITY",
		ast_transfercapability2str(transfercapability));
	if (transfercapability & AST_TRANS_CAP_DIGITAL) {
		sig_pri_set_digital(p, 1);
	}
	if (p->pri) {
		ast_mutex_lock(&p->pri->lock);
		sig_pri_span_devstate_changed(p->pri);
		ast_mutex_unlock(&p->pri->lock);
	}

	return c;
}

/*!
 * \internal
 * \brief Open the PRI channel media path.