chan_dahdi.c

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2008, 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 DAHDI for Pseudo TDM
 *
 * \author Mark Spencer <markster@digium.com>
 *
 * Connects to the DAHDI telephony library as well as
 * libpri. Libpri is optional and needed only if you are
 * going to use ISDN connections.
 *
 * You need to install libraries before you attempt to compile
 * and install the DAHDI channel.
 *
 * \ingroup channel_drivers
 *
 * \todo Deprecate the "musiconhold" configuration option post 1.4
 */

/*!
 * \li The channel chan_dahdi uses the configuration file \ref chan_dahdi.conf
 * \addtogroup configuration_file
 */

/*! \page chan_dahdi.conf chan_dahdi.conf
 * \verbinclude chan_dahdi.conf.sample
 */

/*** MODULEINFO
	<use type="module">res_smdi</use>
	<depend>dahdi</depend>
	<depend>tonezone</depend>
	<use type="external">pri</use>
	<use type="external">ss7</use>
	<use type="external">openr2</use>
	<support_level>core</support_level>
 ***/

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#if defined(__NetBSD__) || defined(__FreeBSD__)
#include <pthread.h>
#include <signal.h>
#else
#include <sys/signal.h>
#endif
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <math.h>
#include <ctype.h>

#include <dahdi/user.h>
#include <dahdi/tonezone.h>
#include "sig_analog.h"
/* Analog signaling is currently still present in chan_dahdi for use with
 * radio. Sig_analog does not currently handle any radio operations. If
 * radio only uses analog signaling, then the radio handling logic could
 * be placed in sig_analog and the duplicated code could be removed.
 */

#if defined(HAVE_PRI)
#include "sig_pri.h"
#ifndef PRI_RESTART
#error "Upgrade your libpri"
#endif
#endif	/* defined(HAVE_PRI) */

#if defined(HAVE_SS7)
#include "sig_ss7.h"
#if defined(LIBSS7_ABI_COMPATIBILITY)
#error "Your installed libss7 is not compatible"
#endif
#endif	/* defined(HAVE_SS7) */

#ifdef HAVE_OPENR2
/* put this here until sig_mfcr2 comes along */
#define SIG_MFCR2_MAX_CHANNELS	672		/*!< No more than a DS3 per trunk group */
#include <openr2.h>
#endif

#include "asterisk/lock.h"
#include "asterisk/channel.h"
#include "asterisk/config.h"
#include "asterisk/module.h"
#include "asterisk/pbx.h"
#include "asterisk/file.h"
#include "asterisk/ulaw.h"
#include "asterisk/alaw.h"
#include "asterisk/callerid.h"
#include "asterisk/adsi.h"
#include "asterisk/cli.h"
#include "asterisk/cdr.h"
#include "asterisk/cel.h"
#include "asterisk/features.h"
#include "asterisk/musiconhold.h"
#include "asterisk/say.h"
#include "asterisk/tdd.h"
#include "asterisk/app.h"
#include "asterisk/dsp.h"
#include "asterisk/astdb.h"
#include "asterisk/manager.h"
#include "asterisk/causes.h"
#include "asterisk/term.h"
#include "asterisk/utils.h"
#include "asterisk/transcap.h"
#include "asterisk/stringfields.h"
#include "asterisk/abstract_jb.h"
#include "asterisk/smdi.h"
#include "asterisk/astobj.h"
#include "asterisk/event.h"
#include "asterisk/devicestate.h"
#include "asterisk/paths.h"
#include "asterisk/ccss.h"
#include "asterisk/data.h"

/*** DOCUMENTATION
	<application name="DAHDISendKeypadFacility" language="en_US">
		<synopsis>
			Send digits out of band over a PRI.
		</synopsis>
		<syntax>
			<parameter name="digits" required="true" />
		</syntax>
		<description>
			<para>This application will send the given string of digits in a Keypad
			Facility IE over the current channel.</para>
		</description>
	</application>
	<application name="DAHDISendCallreroutingFacility" language="en_US">
		<synopsis>
			Send an ISDN call rerouting/deflection facility message.
		</synopsis>
		<syntax argsep=",">
			<parameter name="destination" required="true">
				<para>Destination number.</para>
			</parameter>
			<parameter name="original">
				<para>Original called number.</para>
			</parameter>
			<parameter name="reason">
				<para>Diversion reason, if not specified defaults to <literal>unknown</literal></para>
			</parameter>
		</syntax>
		<description>
			<para>This application will send an ISDN switch specific call
			rerouting/deflection facility message over the current channel.
			Supported switches depend upon the version of libpri in use.</para>
		</description>
	</application>
	<application name="DAHDIAcceptR2Call" language="en_US">
		<synopsis>
			Accept an R2 call if its not already accepted (you still need to answer it)
		</synopsis>
		<syntax>
			<parameter name="charge" required="true">
				<para>Yes or No.</para>
				<para>Whether you want to accept the call with charge or without charge.</para>
			</parameter>
		</syntax>
		<description>
			<para>This application will Accept the R2 call either with charge or no charge.</para>
		</description>
	</application>
	<manager name="DAHDITransfer" language="en_US">
		<synopsis>
			Transfer DAHDI Channel.
		</synopsis>
		<syntax>
			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
			<parameter name="DAHDIChannel" required="true">
				<para>DAHDI channel number to transfer.</para>
			</parameter>
		</syntax>
		<description>
			<para>Simulate a flash hook event by the user connected to the channel.</para>
			<note><para>Valid only for analog channels.</para></note>
		</description>
	</manager>
	<manager name="DAHDIHangup" language="en_US">
		<synopsis>
			Hangup DAHDI Channel.
		</synopsis>
		<syntax>
			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
			<parameter name="DAHDIChannel" required="true">
				<para>DAHDI channel number to hangup.</para>
			</parameter>
		</syntax>
		<description>
			<para>Simulate an on-hook event by the user connected to the channel.</para>
			<note><para>Valid only for analog channels.</para></note>
		</description>
	</manager>
	<manager name="DAHDIDialOffhook" language="en_US">
		<synopsis>
			Dial over DAHDI channel while offhook.
		</synopsis>
		<syntax>
			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
			<parameter name="DAHDIChannel" required="true">
				<para>DAHDI channel number to dial digits.</para>
			</parameter>
			<parameter name="Number" required="true">
				<para>Digits to dial.</para>
			</parameter>
		</syntax>
		<description>
			<para>Generate DTMF control frames to the bridged peer.</para>
		</description>
	</manager>
	<manager name="DAHDIDNDon" language="en_US">
		<synopsis>
			Toggle DAHDI channel Do Not Disturb status ON.
		</synopsis>
		<syntax>
			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
			<parameter name="DAHDIChannel" required="true">
				<para>DAHDI channel number to set DND on.</para>
			</parameter>
		</syntax>
		<description>
			<para>Equivalent to the CLI command "dahdi set dnd <variable>channel</variable> on".</para>
			<note><para>Feature only supported by analog channels.</para></note>
		</description>
	</manager>
	<manager name="DAHDIDNDoff" language="en_US">
		<synopsis>
			Toggle DAHDI channel Do Not Disturb status OFF.
		</synopsis>
		<syntax>
			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
			<parameter name="DAHDIChannel" required="true">
				<para>DAHDI channel number to set DND off.</para>
			</parameter>
		</syntax>
		<description>
			<para>Equivalent to the CLI command "dahdi set dnd <variable>channel</variable> off".</para>
			<note><para>Feature only supported by analog channels.</para></note>
		</description>
	</manager>
	<manager name="DAHDIShowChannels" language="en_US">
		<synopsis>
			Show status of DAHDI channels.
		</synopsis>
		<syntax>
			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
			<parameter name="DAHDIChannel">
				<para>Specify the specific channel number to show.  Show all channels if zero or not present.</para>
			</parameter>
		</syntax>
		<description>
			<para>Similar to the CLI command "dahdi show channels".</para>
		</description>
	</manager>
	<manager name="DAHDIRestart" language="en_US">
		<synopsis>
			Fully Restart DAHDI channels (terminates calls).
		</synopsis>
		<syntax>
			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
		</syntax>
		<description>
			<para>Equivalent to the CLI command "dahdi restart".</para>
		</description>
	</manager>
	<manager name="PRIShowSpans" language="en_US">
		<synopsis>
			Show status of PRI spans.
		</synopsis>
		<syntax>
			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
			<parameter name="Span">
				<para>Specify the specific span to show.  Show all spans if zero or not present.</para>
			</parameter>
		</syntax>
		<description>
			<para>Similar to the CLI command "pri show spans".</para>
		</description>
	</manager>
 ***/

#define SMDI_MD_WAIT_TIMEOUT 1500 /* 1.5 seconds */

static const char * const lbostr[] = {
"0 db (CSU)/0-133 feet (DSX-1)",
"133-266 feet (DSX-1)",
"266-399 feet (DSX-1)",
"399-533 feet (DSX-1)",
"533-655 feet (DSX-1)",
"-7.5db (CSU)",
"-15db (CSU)",
"-22.5db (CSU)"
};

/*! Global jitterbuffer configuration - by default, jb is disabled
 *  \note Values shown here match the defaults shown in chan_dahdi.conf.sample */
static struct ast_jb_conf default_jbconf =
{
	.flags = 0,
	.max_size = 200,
	.resync_threshold = 1000,
	.impl = "fixed",
	.target_extra = 40,
};
static struct ast_jb_conf global_jbconf;

/*!
 * \note Define ZHONE_HACK to cause us to go off hook and then back on hook when
 * the user hangs up to reset the state machine so ring works properly.
 * This is used to be able to support kewlstart by putting the zhone in
 * groundstart mode since their forward disconnect supervision is entirely
 * broken even though their documentation says it isn't and their support
 * is entirely unwilling to provide any assistance with their channel banks
 * even though their web site says they support their products for life.
 */
/* #define ZHONE_HACK */

/*! \brief Typically, how many rings before we should send Caller*ID */
#define DEFAULT_CIDRINGS 1

#define AST_LAW(p) (((p)->law == DAHDI_LAW_ALAW) ? AST_FORMAT_ALAW : AST_FORMAT_ULAW)


/*! \brief Signaling types that need to use MF detection should be placed in this macro */
#define NEED_MFDETECT(p) (((p)->sig == SIG_FEATDMF) || ((p)->sig == SIG_FEATDMF_TA) || ((p)->sig == SIG_E911) || ((p)->sig == SIG_FGC_CAMA) || ((p)->sig == SIG_FGC_CAMAMF) || ((p)->sig == SIG_FEATB))

static const char tdesc[] = "DAHDI Telephony Driver"
#if defined(HAVE_PRI) || defined(HAVE_SS7) || defined(HAVE_OPENR2)
	" w/"
	#if defined(HAVE_PRI)
		"PRI"
	#endif	/* defined(HAVE_PRI) */
	#if defined(HAVE_SS7)
		#if defined(HAVE_PRI)
		" & "
		#endif	/* defined(HAVE_PRI) */
		"SS7"
	#endif	/* defined(HAVE_SS7) */
	#if defined(HAVE_OPENR2)
		#if defined(HAVE_PRI) || defined(HAVE_SS7)
		" & "
		#endif	/* defined(HAVE_PRI) || defined(HAVE_SS7) */
		"MFC/R2"
	#endif	/* defined(HAVE_OPENR2) */
#endif	/* defined(HAVE_PRI) || defined(HAVE_SS7) || defined(HAVE_OPENR2) */
;

static const char config[] = "chan_dahdi.conf";

#define SIG_EM		DAHDI_SIG_EM
#define SIG_EMWINK 	(0x0100000 | DAHDI_SIG_EM)
#define SIG_FEATD	(0x0200000 | DAHDI_SIG_EM)
#define	SIG_FEATDMF	(0x0400000 | DAHDI_SIG_EM)
#define	SIG_FEATB	(0x0800000 | DAHDI_SIG_EM)
#define	SIG_E911	(0x1000000 | DAHDI_SIG_EM)
#define	SIG_FEATDMF_TA	(0x2000000 | DAHDI_SIG_EM)
#define	SIG_FGC_CAMA	(0x4000000 | DAHDI_SIG_EM)
#define	SIG_FGC_CAMAMF	(0x8000000 | DAHDI_SIG_EM)
#define SIG_FXSLS	DAHDI_SIG_FXSLS
#define SIG_FXSGS	DAHDI_SIG_FXSGS
#define SIG_FXSKS	DAHDI_SIG_FXSKS
#define SIG_FXOLS	DAHDI_SIG_FXOLS
#define SIG_FXOGS	DAHDI_SIG_FXOGS
#define SIG_FXOKS	DAHDI_SIG_FXOKS
#define SIG_PRI		DAHDI_SIG_CLEAR
#define SIG_BRI		(0x2000000 | DAHDI_SIG_CLEAR)
#define SIG_BRI_PTMP	(0X4000000 | DAHDI_SIG_CLEAR)
#define SIG_SS7		(0x1000000 | DAHDI_SIG_CLEAR)
#define SIG_MFCR2 	DAHDI_SIG_CAS
#define	SIG_SF		DAHDI_SIG_SF
#define SIG_SFWINK 	(0x0100000 | DAHDI_SIG_SF)
#define SIG_SF_FEATD	(0x0200000 | DAHDI_SIG_SF)
#define	SIG_SF_FEATDMF	(0x0400000 | DAHDI_SIG_SF)
#define	SIG_SF_FEATB	(0x0800000 | DAHDI_SIG_SF)
#define SIG_EM_E1	DAHDI_SIG_EM_E1

#ifdef LOTS_OF_SPANS
#define NUM_SPANS	DAHDI_MAX_SPANS
#else
#define NUM_SPANS 		32
#endif

#define CHAN_PSEUDO	-2

#define CALLPROGRESS_PROGRESS		1
#define CALLPROGRESS_FAX_OUTGOING	2
#define CALLPROGRESS_FAX_INCOMING	4
#define CALLPROGRESS_FAX		(CALLPROGRESS_FAX_INCOMING | CALLPROGRESS_FAX_OUTGOING)

#define NUM_CADENCE_MAX 25
static int num_cadence = 4;
static int user_has_defined_cadences = 0;

static struct dahdi_ring_cadence cadences[NUM_CADENCE_MAX] = {
	{ { 125, 125, 2000, 4000 } },			/*!< Quick chirp followed by normal ring */
	{ { 250, 250, 500, 1000, 250, 250, 500, 4000 } }, /*!< British style ring */
	{ { 125, 125, 125, 125, 125, 4000 } },	/*!< Three short bursts */
	{ { 1000, 500, 2500, 5000 } },	/*!< Long ring */
};

/*! \brief cidrings says in which pause to transmit the cid information, where the first pause
 * is 1, the second pause is 2 and so on.
 */

static int cidrings[NUM_CADENCE_MAX] = {
	2,										/*!< Right after first long ring */
	4,										/*!< Right after long part */
	3,										/*!< After third chirp */
	2,										/*!< Second spell */
};

/* ETSI EN300 659-1 specifies the ring pulse between 200 and 300 mS */
static struct dahdi_ring_cadence AS_RP_cadence = {{250, 10000}};

#define ISTRUNK(p) ((p->sig == SIG_FXSLS) || (p->sig == SIG_FXSKS) || \
			(p->sig == SIG_FXSGS) || (p->sig == SIG_PRI))

#define CANBUSYDETECT(p) (ISTRUNK(p) || (p->sig & (SIG_EM | SIG_EM_E1 | SIG_SF)) /* || (p->sig & __DAHDI_SIG_FXO) */)
#define CANPROGRESSDETECT(p) (ISTRUNK(p) || (p->sig & (SIG_EM | SIG_EM_E1 | SIG_SF)) /* || (p->sig & __DAHDI_SIG_FXO) */)

static char defaultcic[64] = "";
static char defaultozz[64] = "";

/*! Run this script when the MWI state changes on an FXO line, if mwimonitor is enabled */
static char mwimonitornotify[PATH_MAX] = "";
#ifndef HAVE_DAHDI_LINEREVERSE_VMWI
static int  mwisend_rpas = 0;
#endif

static char progzone[10] = "";

static int usedistinctiveringdetection = 0;
static int distinctiveringaftercid = 0;

static int numbufs = 4;

static int mwilevel = 512;
static int dtmfcid_level = 256;

#define REPORT_CHANNEL_ALARMS 1
#define REPORT_SPAN_ALARMS    2 
static int report_alarms = REPORT_CHANNEL_ALARMS;

#ifdef HAVE_PRI
static int pridebugfd = -1;
static char pridebugfilename[1024] = "";
#endif

/*! \brief Wait up to 16 seconds for first digit (FXO logic) */
static int firstdigittimeout = 16000;

/*! \brief How long to wait for following digits (FXO logic) */
static int gendigittimeout = 8000;

/*! \brief How long to wait for an extra digit, if there is an ambiguous match */
static int matchdigittimeout = 3000;

/*! \brief Protect the interface list (of dahdi_pvt's) */
AST_MUTEX_DEFINE_STATIC(iflock);


static int ifcount = 0;

#ifdef HAVE_PRI
AST_MUTEX_DEFINE_STATIC(pridebugfdlock);
#endif

/*! \brief Protect the monitoring thread, so only one process can kill or start it, and not
   when it's doing something critical. */
AST_MUTEX_DEFINE_STATIC(monlock);

/*! \brief This is the thread for the monitor which checks for input on the channels
   which are not currently in use. */
static pthread_t monitor_thread = AST_PTHREADT_NULL;
static ast_cond_t ss_thread_complete;
AST_MUTEX_DEFINE_STATIC(ss_thread_lock);
AST_MUTEX_DEFINE_STATIC(restart_lock);
static int ss_thread_count = 0;
static int num_restart_pending = 0;

static int restart_monitor(void);

static enum ast_bridge_result dahdi_bridge(struct ast_channel *c0, struct ast_channel *c1, int flags, struct ast_frame **fo, struct ast_channel **rc, int timeoutms);

static int dahdi_sendtext(struct ast_channel *c, const char *text);

static void mwi_event_cb(const struct ast_event *event, void *userdata)
{
	/* This module does not handle MWI in an event-based manner.  However, it
	 * subscribes to MWI for each mailbox that is configured so that the core
	 * knows that we care about it.  Then, chan_dahdi will get the MWI from the
	 * event cache instead of checking the mailbox directly. */
}

/*! \brief Avoid the silly dahdi_getevent which ignores a bunch of events */
static inline int dahdi_get_event(int fd)
{
	int j;
	if (ioctl(fd, DAHDI_GETEVENT, &j) == -1)
		return -1;
	return j;
}

/*! \brief Avoid the silly dahdi_waitevent which ignores a bunch of events */
static inline int dahdi_wait_event(int fd)
{
	int i, j = 0;
	i = DAHDI_IOMUX_SIGEVENT;
	if (ioctl(fd, DAHDI_IOMUX, &i) == -1)
		return -1;
	if (ioctl(fd, DAHDI_GETEVENT, &j) == -1)
		return -1;
	return j;
}

/*! Chunk size to read -- we use 20ms chunks to make things happy. */
#define READ_SIZE 160

#define MASK_AVAIL		(1 << 0)	/*!< Channel available for PRI use */
#define MASK_INUSE		(1 << 1)	/*!< Channel currently in use */

#define CALLWAITING_SILENT_SAMPLES		((300 * 8) / READ_SIZE) /*!< 300 ms */
#define CALLWAITING_REPEAT_SAMPLES		((10000 * 8) / READ_SIZE) /*!< 10,000 ms */
#define CALLWAITING_SUPPRESS_SAMPLES	((100 * 8) / READ_SIZE) /*!< 100 ms */
#define CIDCW_EXPIRE_SAMPLES			((500 * 8) / READ_SIZE) /*!< 500 ms */
#define MIN_MS_SINCE_FLASH				((2000) )	/*!< 2000 ms */
#define DEFAULT_RINGT 					((8000 * 8) / READ_SIZE) /*!< 8,000 ms */
#define DEFAULT_DIALTONE_DETECT_TIMEOUT ((10000 * 8) / READ_SIZE) /*!< 10,000 ms */

struct dahdi_pvt;

/*!
 * \brief Configured ring timeout base.
 * \note Value computed from "ringtimeout" read in from chan_dahdi.conf if it exists.
 */
static int ringt_base = DEFAULT_RINGT;

#if defined(HAVE_SS7)

struct dahdi_ss7 {
	struct sig_ss7_linkset ss7;
};

static struct dahdi_ss7 linksets[NUM_SPANS];

static int cur_ss7type = -1;
static int cur_linkset = -1;
static int cur_pointcode = -1;
static int cur_cicbeginswith = -1;
static int cur_adjpointcode = -1;
static int cur_networkindicator = -1;
static int cur_defaultdpc = -1;
#endif	/* defined(HAVE_SS7) */

#ifdef HAVE_OPENR2
struct dahdi_mfcr2 {
	pthread_t r2master;		       /*!< Thread of master */
	openr2_context_t *protocol_context;    /*!< OpenR2 context handle */
	struct dahdi_pvt *pvts[SIG_MFCR2_MAX_CHANNELS];     /*!< Member channel pvt structs */
	int numchans;                          /*!< Number of channels in this R2 block */
	int monitored_count;                   /*!< Number of channels being monitored */
};

struct dahdi_mfcr2_conf {
	openr2_variant_t variant;
	int mfback_timeout;
	int metering_pulse_timeout;
	int max_ani;
	int max_dnis;
#if defined(OR2_LIB_INTERFACE) && OR2_LIB_INTERFACE > 2
	int dtmf_time_on;
	int dtmf_time_off;
#endif
#if defined(OR2_LIB_INTERFACE) && OR2_LIB_INTERFACE > 3
	int dtmf_end_timeout;
#endif
	signed int get_ani_first:2;
#if defined(OR2_LIB_INTERFACE) && OR2_LIB_INTERFACE > 1
	signed int skip_category_request:2;
#endif
	unsigned int call_files:1;
	unsigned int allow_collect_calls:1;
	unsigned int charge_calls:1;
	unsigned int accept_on_offer:1;
	unsigned int forced_release:1;
	unsigned int double_answer:1;
	signed int immediate_accept:2;
#if defined(OR2_LIB_INTERFACE) && OR2_LIB_INTERFACE > 2
	signed int dtmf_dialing:2;
	signed int dtmf_detection:2;
#endif
	char logdir[OR2_MAX_PATH];
	char r2proto_file[OR2_MAX_PATH];
	openr2_log_level_t loglevel;
	openr2_calling_party_category_t category;
};

/* malloc'd array of malloc'd r2links */
static struct dahdi_mfcr2 **r2links;
/* how many r2links have been malloc'd */
static int r2links_count = 0;

#endif /* HAVE_OPENR2 */

#ifdef HAVE_PRI

struct dahdi_pri {
	int dchannels[SIG_PRI_NUM_DCHANS];		/*!< What channel are the dchannels on */
	int mastertrunkgroup;					/*!< What trunk group is our master */
	int prilogicalspan;						/*!< Logical span number within trunk group */
	struct sig_pri_span pri;
};

static struct dahdi_pri pris[NUM_SPANS];

#if defined(HAVE_PRI_CCSS)
/*! DAHDI PRI CCSS agent and monitor type name. */
static const char dahdi_pri_cc_type[] = "DAHDI/PRI";
#endif	/* defined(HAVE_PRI_CCSS) */

#else
/*! Shut up the compiler */
struct dahdi_pri;
#endif

#define SUB_REAL	0			/*!< Active call */
#define SUB_CALLWAIT	1			/*!< Call-Waiting call on hold */
#define SUB_THREEWAY	2			/*!< Three-way call */

/* Polarity states */
#define POLARITY_IDLE   0
#define POLARITY_REV    1


struct distRingData {
	int ring[3];
	int range;
};
struct ringContextData {
	char contextData[AST_MAX_CONTEXT];
};
struct dahdi_distRings {
	struct distRingData ringnum[3];
	struct ringContextData ringContext[3];
};

static const char * const subnames[] = {
	"Real",
	"Callwait",
	"Threeway"
};

struct dahdi_subchannel {
	int dfd;
	struct ast_channel *owner;
	int chan;
	short buffer[AST_FRIENDLY_OFFSET/2 + READ_SIZE];
	struct ast_frame f;		/*!< One frame for each channel.  How did this ever work before? */
	unsigned int needringing:1;
	unsigned int needbusy:1;
	unsigned int needcongestion:1;
	unsigned int needanswer:1;
	unsigned int needflash:1;
	unsigned int needhold:1;
	unsigned int needunhold:1;
	unsigned int linear:1;
	unsigned int inthreeway:1;
	struct dahdi_confinfo curconf;
};

#define CONF_USER_REAL		(1 << 0)
#define CONF_USER_THIRDCALL	(1 << 1)

#define MAX_SLAVES	4

/* States for sending MWI message
 * First three states are required for send Ring Pulse Alert Signal
 */
typedef enum {
	MWI_SEND_NULL = 0,
	MWI_SEND_SA,
	MWI_SEND_SA_WAIT,
	MWI_SEND_PAUSE,
	MWI_SEND_SPILL,
	MWI_SEND_CLEANUP,
	MWI_SEND_DONE,
} mwisend_states;

struct mwisend_info {
	struct	timeval	pause;
	mwisend_states 	mwisend_current;
};

/*! Specify the lists dahdi_pvt can be put in. */
enum DAHDI_IFLIST {
	DAHDI_IFLIST_NONE,	/*!< The dahdi_pvt is not in any list. */
	DAHDI_IFLIST_MAIN,	/*!< The dahdi_pvt is in the main interface list */
#if defined(HAVE_PRI)
	DAHDI_IFLIST_NO_B_CHAN,	/*!< The dahdi_pvt is in a no B channel interface list */
#endif	/* defined(HAVE_PRI) */
};

struct dahdi_pvt {
	ast_mutex_t lock;					/*!< Channel private lock. */
	struct callerid_state *cs;
	struct ast_channel *owner;			/*!< Our current active owner (if applicable) */
							/*!< Up to three channels can be associated with this call */

	struct dahdi_subchannel sub_unused;		/*!< Just a safety precaution */
	struct dahdi_subchannel subs[3];			/*!< Sub-channels */
	struct dahdi_confinfo saveconf;			/*!< Saved conference info */

	struct dahdi_pvt *slaves[MAX_SLAVES];		/*!< Slave to us (follows our conferencing) */
	struct dahdi_pvt *master;				/*!< Master to us (we follow their conferencing) */
	int inconference;				/*!< If our real should be in the conference */

	int bufsize;                /*!< Size of the buffers */
	int buf_no;					/*!< Number of buffers */
	int buf_policy;				/*!< Buffer policy */
	int faxbuf_no;              /*!< Number of Fax buffers */
	int faxbuf_policy;          /*!< Fax buffer policy */
	int sig;					/*!< Signalling style */
	/*!
	 * \brief Nonzero if the signaling type is sent over a radio.
	 * \note Set to a couple of nonzero values but it is only tested like a boolean.
	 */
	int radio;
	int outsigmod;					/*!< Outbound Signalling style (modifier) */
	int oprmode;					/*!< "Operator Services" mode */
	struct dahdi_pvt *oprpeer;				/*!< "Operator Services" peer tech_pvt ptr */
	/*! \brief Amount of gain to increase during caller id */
	float cid_rxgain;
	/*! \brief Rx gain set by chan_dahdi.conf */
	float rxgain;
	/*! \brief Tx gain set by chan_dahdi.conf */
	float txgain;

	float txdrc; /*!< Dynamic Range Compression factor. a number between 1 and 6ish */
	float rxdrc;
	
	int tonezone;					/*!< tone zone for this chan, or -1 for default */
	enum DAHDI_IFLIST which_iflist;	/*!< Which interface list is this structure listed? */
	struct dahdi_pvt *next;				/*!< Next channel in list */
	struct dahdi_pvt *prev;				/*!< Prev channel in list */

	/* flags */

	/*!
	 * \brief TRUE if ADSI (Analog Display Services Interface) available
	 * \note Set from the "adsi" value read in from chan_dahdi.conf
	 */
	unsigned int adsi:1;
	/*!
	 * \brief TRUE if we can use a polarity reversal to mark when an outgoing
	 * call is answered by the remote party.
	 * \note Set from the "answeronpolarityswitch" value read in from chan_dahdi.conf
	 */
	unsigned int answeronpolarityswitch:1;
	/*!
	 * \brief TRUE if busy detection is enabled.
	 * (Listens for the beep-beep busy pattern.)
	 * \note Set from the "busydetect" value read in from chan_dahdi.conf
	 */
	unsigned int busydetect:1;
	/*!
	 * \brief TRUE if call return is enabled.
	 * (*69, if your dialplan doesn't catch this first)
	 * \note Set from the "callreturn" value read in from chan_dahdi.conf
	 */
	unsigned int callreturn:1;
	/*!
	 * \brief TRUE if busy extensions will hear the call-waiting tone
	 * and can use hook-flash to switch between callers.
	 * \note Can be disabled by dialing *70.
	 * \note Initialized with the "callwaiting" value read in from chan_dahdi.conf
	 */
	unsigned int callwaiting:1;
	/*!
	 * \brief TRUE if send caller ID for Call Waiting
	 * \note Set from the "callwaitingcallerid" value read in from chan_dahdi.conf
	 */
	unsigned int callwaitingcallerid:1;
	/*!
	 * \brief TRUE if support for call forwarding enabled.
	 * Dial *72 to enable call forwarding.
	 * Dial *73 to disable call forwarding.
	 * \note Set from the "cancallforward" value read in from chan_dahdi.conf
	 */
	unsigned int cancallforward:1;
	/*!
	 * \brief TRUE if support for call parking is enabled.
	 * \note Set from the "canpark" value read in from chan_dahdi.conf
	 */
	unsigned int canpark:1;
	/*! \brief TRUE if to wait for a DTMF digit to confirm answer */
	unsigned int confirmanswer:1;
	/*!
	 * \brief TRUE if the channel is to be destroyed on hangup.
	 * (Used by pseudo channels.)
	 */
	unsigned int destroy:1;
	unsigned int didtdd:1;				/*!< flag to say its done it once */
	/*! \brief TRUE if analog type line dialed no digits in Dial() */
	unsigned int dialednone:1;
	/*!
	 * \brief TRUE if in the process of dialing digits or sending something.
	 * \note This is used as a receive squelch for ISDN until connected.
	 */
	unsigned int dialing:1;
	/*! \brief TRUE if the transfer capability of the call is digital. */
	unsigned int digital:1;
	/*! \brief TRUE if Do-Not-Disturb is enabled, present only for non sig_analog */
	unsigned int dnd:1;
	/*! \brief XXX BOOLEAN Purpose??? */
	unsigned int echobreak:1;
	/*!
	 * \brief TRUE if echo cancellation enabled when bridged.
	 * \note Initialized with the "echocancelwhenbridged" value read in from chan_dahdi.conf
	 * \note Disabled if the echo canceller is not setup.
	 */
	unsigned int echocanbridged:1;
	/*! \brief TRUE if echo cancellation is turned on. */
	unsigned int echocanon:1;
	/*! \brief TRUE if a fax tone has already been handled. */
	unsigned int faxhandled:1;
	/*! TRUE if dynamic faxbuffers are configured for use, default is OFF */
	unsigned int usefaxbuffers:1;
	/*! TRUE while buffer configuration override is in use */
	unsigned int bufferoverrideinuse:1;
	/*! \brief TRUE if over a radio and dahdi_read() has been called. */
	unsigned int firstradio:1;
	/*!
	 * \brief TRUE if the call will be considered "hung up" on a polarity reversal.
	 * \note Set from the "hanguponpolarityswitch" value read in from chan_dahdi.conf
	 */
	unsigned int hanguponpolarityswitch:1;
	/*! \brief TRUE if DTMF detection needs to be done by hardware. */
	unsigned int hardwaredtmf:1;
	/*!
	 * \brief TRUE if the outgoing caller ID is blocked/hidden.
	 * \note Caller ID can be disabled by dialing *67.
	 * \note Caller ID can be enabled by dialing *82.
	 * \note Initialized with the "hidecallerid" value read in from chan_dahdi.conf
	 */
	unsigned int hidecallerid:1;
	/*!
	 * \brief TRUE if hide just the name not the number for legacy PBX use.
	 * \note Only applies to PRI channels.
	 * \note Set from the "hidecalleridname" value read in from chan_dahdi.conf
	 */
	unsigned int hidecalleridname:1;
	/*! \brief TRUE if DTMF detection is disabled. */
	unsigned int ignoredtmf:1;
	/*!
	 * \brief TRUE if the channel should be answered immediately
	 * without attempting to gather any digits.
	 * \note Set from the "immediate" value read in from chan_dahdi.conf
	 */
	unsigned int immediate:1;
	/*! \brief TRUE if in an alarm condition. */
	unsigned int inalarm:1;
	/*! \brief TRUE if TDD in MATE mode */
	unsigned int mate:1;
	/*! \brief TRUE if we originated the call leg. */
	unsigned int outgoing:1;
	/* unsigned int overlapdial:1; 			unused and potentially confusing */
	/*!
	 * \brief TRUE if busy extensions will hear the call-waiting tone
	 * and can use hook-flash to switch between callers.
	 * \note Set from the "callwaiting" value read in from chan_dahdi.conf
	 */
	unsigned int permcallwaiting:1;
	/*!
	 * \brief TRUE if the outgoing caller ID is blocked/restricted/hidden.
	 * \note Set from the "hidecallerid" value read in from chan_dahdi.conf
	 */
	unsigned int permhidecallerid:1;
	/*!
	 * \brief TRUE if PRI congestion/busy indications are sent out-of-band.
	 * \note Set from the "priindication" value read in from chan_dahdi.conf
	 */
	unsigned int priindication_oob:1;
	/*!
	 * \brief TRUE if PRI B channels are always exclusively selected.
	 * \note Set from the "priexclusive" value read in from chan_dahdi.conf
	 */
	unsigned int priexclusive:1;
	/*!
	 * \brief TRUE if we will pulse dial.
	 * \note Set from the "pulsedial" value read in from chan_dahdi.conf
	 */
	unsigned int pulse:1;
	/*! \brief TRUE if a pulsed digit was detected. (Pulse dial phone detected) */
	unsigned int pulsedial:1;
	unsigned int restartpending:1;		/*!< flag to ensure counted only once for restart */
	/*!
	 * \brief TRUE if caller ID is restricted.
	 * \note Set but not used.  Should be deleted.  Redundant with permhidecallerid.
	 * \note Set from the "restrictcid" value read in from chan_dahdi.conf
	 */
	unsigned int restrictcid:1;
	/*!
	 * \brief TRUE if three way calling is enabled
	 * \note Set from the "threewaycalling" value read in from chan_dahdi.conf
	 */
	unsigned int threewaycalling:1;
	/*!
	 * \brief TRUE if call transfer is enabled
	 * \note For FXS ports (either direct analog or over T1/E1):
	 *   Support flash-hook call transfer
	 * \note For digital ports using ISDN PRI protocols:
	 *   Support switch-side transfer (called 2BCT, RLT or other names)
	 * \note Set from the "transfer" value read in from chan_dahdi.conf
	 */
	unsigned int transfer:1;
	/*!
	 * \brief TRUE if caller ID is used on this channel.
	 * \note PRI and SS7 spans will save caller ID from the networking peer.
	 * \note FXS ports will generate the caller ID spill.
	 * \note FXO ports will listen for the caller ID spill.
	 * \note Set from the "usecallerid" value read in from chan_dahdi.conf
	 */
	unsigned int use_callerid:1;
	/*!
	 * \brief TRUE if we will use the calling presentation setting
	 * from the Asterisk channel for outgoing calls.
	 * \note Only applies to PRI and SS7 channels.
	 * \note Set from the "usecallingpres" value read in from chan_dahdi.conf
	 */
	unsigned int use_callingpres:1;
	/*!
	 * \brief TRUE if distinctive rings are to be detected.
	 * \note For FXO lines
	 * \note Set indirectly from the "usedistinctiveringdetection" value read in from chan_dahdi.conf
	 */
	unsigned int usedistinctiveringdetection:1;
	/*!
	 * \brief TRUE if we should use the callerid from incoming call on dahdi transfer.
	 * \note Set from the "useincomingcalleridondahditransfer" value read in from chan_dahdi.conf
	 */
	unsigned int dahditrcallerid:1;
	/*!
	 * \brief TRUE if allowed to flash-transfer to busy channels.
	 * \note Set from the "transfertobusy" value read in from chan_dahdi.conf
	 */
	unsigned int transfertobusy:1;
	/*!
	 * \brief TRUE if the FXO port monitors for neon type MWI indications from the other end.
	 * \note Set if the "mwimonitor" value read in contains "neon" from chan_dahdi.conf
	 */
	unsigned int mwimonitor_neon:1;
	/*!
	 * \brief TRUE if the FXO port monitors for fsk type MWI indications from the other end.
	 * \note Set if the "mwimonitor" value read in contains "fsk" from chan_dahdi.conf
	 */
	unsigned int mwimonitor_fsk:1;
	/*!
	 * \brief TRUE if the FXO port monitors for rpas precursor to fsk MWI indications from the other end.
	 * \note RPAS - Ring Pulse Alert Signal
	 * \note Set if the "mwimonitor" value read in contains "rpas" from chan_dahdi.conf
	 */
	unsigned int mwimonitor_rpas:1;
	/*! \brief TRUE if an MWI monitor thread is currently active */
	unsigned int mwimonitoractive:1;
	/*! \brief TRUE if a MWI message sending thread is active */
	unsigned int mwisendactive:1;
	/*!
	 * \brief TRUE if channel is out of reset and ready
	 * \note Set but not used.
	 */
	unsigned int inservice:1;
	/*!
	 * \brief TRUE if the channel is locally blocked.
	 * \note Applies to SS7 and MFCR2 channels.
	 */
	unsigned int locallyblocked:1;
	/*!
	 * \brief TRUE if the channel is remotely blocked.
	 * \note Applies to SS7 and MFCR2 channels.
	 */
	unsigned int remotelyblocked:1;