osmo-cc-pstn-endpoint/src/pstn/pstn.h

#include "../libtimer/timer.h"
#include "../libselect/select.h"
#include "../libosmocc/endpoint.h"
#include "../libsample/sample.h"
#include "../libjitter/jitter.h"
#include "../libdtmf/dtmf_decode.h"
#include "../libph_socket/ph_socket.h"
#include "callerid.h"
#include "tones.h"

enum pstn_state {
	PSTN_STATE_OOS = 0,	/* out of service */
	PSTN_STATE_NULL,	/* no call */
	PSTN_STATE_EST_LE,	/* requested establisment, waiting for reply */
	PSTN_STATE_EST_AN,	/* not used here */
	PSTN_STATE_ACTIVE,	/* path active */
	PSTN_STATE_DISC_REQ,	/* requested disconnect, waiting for reply */
	PSTN_STATE_BLOCKED,	/* not used here */
};

enum pstn_event {
	PSTN_EVENT_EST_REQ	= 0x00,	/* establishment towards interface */
	PSTN_EVENT_EST_ACK_IND	= 0x03,	/* establishment acknowledge from interface */
	PSTN_EVENT_EST_IND	= 0x01,	/* establishment from interface */
	PSTN_EVENT_EST_ACK_REQ	= 0x02,	/* establishment acknowledge towards interface */
	PSTN_EVENT_SIG_REQ	= 0x10,	/* line signal towards interface */
	PSTN_EVENT_SIG_IND	= 0x11,	/* line signal from interface */
	PSTN_EVENT_PARAM_REQ	= 0x20,	/* parameter request towards interface */
	PSTN_EVENT_DISC_REQ	= 0x30,	/* disconnect towards interface (ACTIVE sate) */
	PSTN_EVENT_DISC_CPL_REQ	= 0x32,	/* disconnect towards interface (PATH INITIATED states) */
	PSTN_EVENT_DISC_CPL_IND	= 0x33,	/* disconnect from interface */
};

enum pstn_v5_ie {
	PSTN_V5_IE_CADENCED_RINGING	= 0x01,
	PSTN_V5_IE_PULSED_SIGNAL	= 0x02,
	PSTN_V5_IE_STEADY_SIGNAL	= 0x03,
	PSTN_V5_IE_DIGIT_SIGNAL		= 0x04,
};

enum pstn_v5_signal {
	PSTN_V5_STEADY_SIGNAL_NORMAL	= 0x00,
	PSTN_V5_STEADY_SIGNAL_REVERSED	= 0x01,
	PSTN_V5_STEADY_SIGNAL_OFF_HOOK	= 0x04,
	PSTN_V5_STEADY_SIGNAL_ON_HOOK	= 0x05,
	PSTN_V5_STEADY_SIGNAL_STOP_RING	= 0x0e,
	PSTN_V5_PULSED_SIGNAL_INIT_RING	= 0x79,
	PSTN_V5_PULSED_SIGNAL_REG_RECAL	= 0x76,
	PSTN_V5_PULSED_SIGNAL_ON_HOOK	= 0x7c,
};

enum timer_ident {
	TIMER_IDENT_DIALING,
	TIMER_IDENT_RELEASE,
	TIMER_IDENT_HOOKFLASH,
};

#define PSTN_CALL_ACTIVE	0
#define PSTN_CALL_HOLD		1

enum pstn_call_state {
	CALL_STATE_NULL = 0,
	CALL_STATE_ENBLOCK,
	CALL_STATE_ALERTING_SUB,
	CALL_STATE_OVERLAP_NET,
	CALL_STATE_PROCEEDING_NET,
	CALL_STATE_ALERTING_NET,
	CALL_STATE_ACTIVE,
	CALL_STATE_HOLD,
	CALL_STATE_DISCONNECT_NET,
};

enum pstn_cid_method {
	CID_METHOD_NONE = 0,
	CID_METHOD_PULSE,
	CID_METHOD_STOP,
	CID_METHOD_DTAS,
	CID_METHOD_DTAS_LR,
};

enum pstn_cid_state {
	PSTN_CID_STATE_OFF = 0,
	PSTN_CID_STATE_WAIT1,
	PSTN_CID_STATE_SEND,
	PSTN_CID_STATE_WAIT2,
};

enum tones_type {
	TONES_TYPE_AMERICAN,
	TONES_TYPE_GERMAN,
	TONES_TYPE_OLDGERMAN,
};

struct pstn;

struct call {
	struct pstn		*pstn;
	uint32_t		cc_callref;
	enum pstn_call_state	state;
	int			subscriber_index;	/* subscriber the calls is associated with */
	const char		*sdp;
	osmo_cc_session_t	*cc_session;
	osmo_cc_session_codec_t	*codec;
	int			on_hold;		/* track hold/retrieval notification */
};

struct dial_hint {
	struct dial_hint	*next;
	size_t			length;
	char			*from, *to;
};

typedef struct pstn {
	osmo_cc_endpoint_t	cc_ep;

	/* settings */
	char			law;			/* 'a'-law or 'u'-law */
	const char		*name;
	const char		**subscribers;		/* subscriber number (caller ID of PSTN port) */
	int			subscriber_num;		/* number of subscribers and tinging types (incoming) */
	int			serving_location;	/* who we serve when sending causes towards interface */
	int			tx_delay;		/* delay to be used for fax/modem jitter buffering */
	enum pstn_cid_method	clip;			/* send caller ID */
	int			clip_date;		/* send date with caller ID */
	int			cid_bell;		/* use V.23 or Bell 202 FSK tones */
	int			cid_dtmf;		/* use DTMF instead of FSK caller ID */
	int			enblock;		/* receive digits before transmitting them via SETUP message (timeout as given) */
	struct dial_hint	dial_hints;		/* list of numbers that are complete */
	int			recall;			/* support recall / waiting call */
	int			*ringing_types_incoming;/* cadenced rining on incoming call */
	int			ringing_type_hold;	/* cadenced rining on waiting call */
	enum tones_type		tones_type;		/* what tone set to use */

	/* states */
	enum pstn_state		state;
	struct timer		timer;			/* timer for enblock dialing */
	enum timer_ident	timer_ident;		/* why is the timer running */
	char			dialing[33];		/* register for en-block dialing */
	int			reversed;		/* if polarity is reversed */
	int			dtmf_on;		/* we are listening to DTMF */
	int			pulse_on;		/* we take pulses */
	enum pstn_cid_state	callerid_state;		/* transmitting callerid */
	int			callerid_wait1;		/* wait (number of samples) until transmitting caller ID */
	int			callerid_wait2;		/* wait (number of samples) after transmitting caller ID */
	int			b_transmitting;		/* transmitting on b-channel */

	/* v5 interface */
	ph_socket_t		ph_socket;

	/* osmo-cc states (active and hold ) */
	struct call		*call[2];

	/* audio states */
	int			audio_path;		/* (early/late) audio is connected */
	jitter_t		tx_dejitter;		/* jitter buffer */
	dtmf_dec_t		dtmf_dec;		/* DTMF tone detection */
	struct isdn_tone	isdn_tone;		/* tone generator */
	callerid_t		callerid;		/* caller ID transmission */
	uint8_t			tx_buffer[160];		/* transmit audio buffer */
        int			tx_buffer_pos;		/* current position in transmit audio buffer */
} pstn_t;

int add_dial_hint(const char *arg);
void purge_dial_hints(void);
void pstn_destroy(pstn_t *pstn_ep);
pstn_t *pstn_create(void);
int pstn_init(pstn_t *pstn, const char *name, const char *socketname, const char **subscribers, int subscriber_num, uint8_t serving_location, int tx_delay, enum pstn_cid_method clip, int cid_bell, int cid_dtmf, int clip_date, int enblock, int recall, int *ringing_types_incoming, int ringing_type_hold, enum tones_type tones_type, char law);
void cc_message(osmo_cc_endpoint_t *ep, uint32_t callref, osmo_cc_msg_t *msg);
void rtp_work(pstn_t *pstn_ep);