gpsd.h-tail

来自「gpsd, a popular GPS daemon.」· H-TAIL 代码 · 共 463 行 · 第 1/2 页

/* Feature configuration switches end here */

/* $Id: gpsd.h-tail 4665 2008-01-21 00:43:01Z garyemiller $ */

/* Some internal capabilities depend on which drivers we're compiling. */
#ifdef EARTHMATE_ENABLE
#define ZODIAC_ENABLE	
#endif
#if defined(ZODIAC_ENABLE) || defined(SIRF_ENABLE) || defined(GARMIN_ENABLE) || defined(TSIP_ENABLE) || defined(EVERMORE_ENABLE) || defined(ITRAX_ENABLE) || defined(UBX_ENABLE)
#define BINARY_ENABLE	
#endif
#if defined(TRIPMATE_ENABLE) || defined(BINARY_ENABLE)
#define NON_NMEA_ENABLE	
#endif

/* First, declarations for the packet layer... */

/* XXX Some receivers (TN-200, GSW 2.3.2) emit oversized sentences (>82) */
#define NMEA_MAX	86		/* max length of NMEA sentence */
#define NMEA_BIG_BUF	(2*NMEA_MAX+1)	/* longer than longest NMEA sentence */

/* a few bits of ISGPS magic */
enum isgpsstat_t {
    ISGPS_NO_SYNC, ISGPS_SYNC, ISGPS_SKIP, ISGPS_MESSAGE,
};
#define ISGPS_ERRLEVEL_BASE	5

#define RTCM_MAX	(RTCM_WORDS_MAX * sizeof(isgps30bits_t))

/*
 * The packet buffers need to be as long than the longest packet we
 * expect to see in any protocol, because we have to be able to hold
 * an entire packet for checksumming...
 * First we thought it had to be big enough for a SiRF Measured Tracker
 * Data packet (188 bytes). Then it had to be big enough for a UBX SVINFO
 * packet (206 bytes). Now it turns out that a couple of ITALK messages are
 * over 512 bytes. I know we like verbose output, but this is ridiculous.
 */
#define MAX_PACKET_LENGTH	516	/* 7 + 506 + 3 */

/*
 * We used to define the input buffer length as MAX_PACKET_LENGTH*2+1.
 * However, as it turns out, this isn't enough.  We've had a report
 * from one user with a GPS that reports at 20Hz that "sometimes a
 * long/slow context switch will cause the next read from the serial
 * device to be very big. I sometimes see a read of 250 characters or
 * more."
 */
#define INPUT_BUFFER_LENGTH	1536

struct gps_packet_t {
    /* packet-getter internals */
    int	type;
#define BAD_PACKET	-1
#define COMMENT_PACKET	0
#define NMEA_PACKET	1
#define SIRF_PACKET	2
#define ZODIAC_PACKET	3
#define TSIP_PACKET	4
#define EVERMORE_PACKET	5
#define ITALK_PACKET	6
#define RTCM_PACKET	7
#define GARMIN_PACKET	8
#define NAVCOM_PACKET	9
#define UBX_PACKET	10
#define GARMINTXT_PACKET	11
    unsigned int state;
    size_t length;
    unsigned char inbuffer[MAX_PACKET_LENGTH*2+1];
    size_t inbuflen;
    unsigned /*@observer@*/char *inbufptr;
    /* outbuffer needs to be able to hold 4 GPGSV records at once */
    unsigned char outbuffer[MAX_PACKET_LENGTH*2+1];
    size_t outbuflen;
    unsigned long char_counter;		/* count characters processed */
    unsigned long retry_counter;	/* count sniff retries */
    unsigned counter;			/* packets since last driver switch */
    /*
     * This is not conditionalized on RTCM104_ENABLE because we need to
     * be able to build rtcmdecode even when RTCM support is not
     * configured in the daemon.
     */
    struct {
	/* ISGPS200 decoding */
	bool            locked;
	int             curr_offset;
	isgps30bits_t   curr_word;
	isgps30bits_t   buf[RTCM_WORDS_MAX];
	unsigned int    bufindex;
    } isgps;
};

extern void packet_reset(struct gps_packet_t *);
extern void packet_pushback(struct gps_packet_t *);
extern ssize_t packet_parse(struct gps_packet_t *, size_t);
extern ssize_t packet_get(int, struct gps_packet_t *);
extern int packet_sniff(struct gps_packet_t *);

extern void isgps_init(/*@out@*/struct gps_packet_t *);
enum isgpsstat_t isgps_decode(struct gps_packet_t *, 
			      bool (*preamble_match)(isgps30bits_t *),
			      bool (*length_check)(struct gps_packet_t *),
			      size_t,
			      unsigned int);
extern unsigned int isgps_parity(isgps30bits_t);
extern void isgps_output_magnavox(isgps30bits_t *, unsigned int, FILE *);

extern enum isgpsstat_t rtcm_decode(struct gps_packet_t *, unsigned int);
extern void rtcm_dump(struct rtcm_t *, /*@out@*/char[], size_t);
extern int rtcm_undump(/*@out@*/struct rtcm_t *, char *);
extern void rtcm_unpack(/*@out@*/struct rtcm_t *, char *);
extern bool rtcm_repack(struct rtcm_t *, isgps30bits_t *);
extern void rtcm_output_magnavox(isgps30bits_t *, FILE *);

/* Next, declarations for the core library... */

/* factors for converting among confidence interval units */
#define CEP50_SIGMA	1.18
#define DRMS_SIGMA	1.414
#define CEP95_SIGMA	2.45

/* this is where we choose the confidence level to use in reports */
#define GPSD_CONFIDENCE	CEP95_SIGMA

#define NTPSHMSEGS	4		/* number of NTP SHM segments */

/* Some internal capabilities depend on which drivers we're compiling. */
#ifdef EARTHMATE_ENABLE
#define ZODIAC_ENABLE	
#endif
#if defined(ZODIAC_ENABLE) || defined(SIRF_ENABLE) || defined(GARMIN_ENABLE) || defined(TSIP_ENABLE) || defined(EVERMORE_ENABLE) || defined(ITRAX_ENABLE)
#define BINARY_ENABLE	
#endif
#if defined(TRIPMATE_ENABLE) || defined(BINARY_ENABLE)
#define NON_NMEA_ENABLE	
#endif

struct gps_context_t {
    int valid;				/* member validity flags */
    bool readonly;			/* if true, never write to device */
#define LEAP_SECOND_VALID	0x01	/* we have or don't need correction */
    /* DGPSIP status */
    bool sentdgps;			/* have we sent a DGPS report? */
    enum { dgnss_none, dgnss_dgpsip, dgnss_ntrip } dgnss_service;	/* type of DGNSS service */
    int fixcnt;				/* count of good fixes seen */
    int dsock;			        /* socket to DGPSIP server/Ntrip caster */
    void *dgnss_privdata;		/* DGNSS service specific data */
    ssize_t rtcmbytes;			/* byte count of last RTCM104 report */
    char rtcmbuf[RTCM_MAX];		/* last RTCM104 report */
    double rtcmtime;			/* timestamp of last RTCM104 report */ 
    /* timekeeping */
    int leap_seconds;			/* Unix seconds to UTC */
    int century;			/* for NMEA-only devices without ZDA */
#ifdef NTPSHM_ENABLE
    bool enable_ntpshm;
    /*@reldef@*/struct shmTime *shmTime[NTPSHMSEGS];
    bool shmTimeInuse[NTPSHMSEGS];
# ifdef PPS_ENABLE
    bool shmTimePPS;
# endif /* PPS_ENABLE */
#endif /* NTPSHM_ENABLE */
};

struct gps_device_t;

#if defined (HAVE_SYS_TERMIOS_H)
#include <sys/termios.h>
#else
#if defined (HAVE_TERMIOS_H)
#include <termios.h>
#endif
#endif

struct gps_type_t {
/* GPS method table, describes how to talk to a particular GPS type */
    /*@observer@*/char *type_name;
    /*@observer@*//*@null@*/char *trigger;
    int channels;
    /*@null@*/bool (*probe_detect)(struct gps_device_t *session);
    /*@null@*/void (*probe_wakeup)(struct gps_device_t *session);
    /*@null@*/void (*probe_subtype)(struct gps_device_t *session, unsigned int seq);
#ifdef ALLOW_RECONFIGURE 
    /*@null@*/void (*configurator)(struct gps_device_t *session, unsigned int seq);
#endif /* ALLOW_RECONFIGURE */
    /*@null@*/ssize_t (*get_packet)(struct gps_device_t *session);
    /*@null@*/gps_mask_t (*parse_packet)(struct gps_device_t *session);
    /*@null@*/ssize_t (*rtcm_writer)(struct gps_device_t *session, char *rtcmbuf, size_t rtcmbytes);
    /*@null@*/bool (*speed_switcher)(struct gps_device_t *session, speed_t speed);
    /*@null@*/void (*mode_switcher)(struct gps_device_t *session, int mode);
    /*@null@*/bool (*rate_switcher)(struct gps_device_t *session, double rate);
    int cycle_chars;
#ifdef ALLOW_RECONFIGURE 
    /*@null@*/void (*revert)(struct gps_device_t *session);
#endif /* ALLOW_RECONFIGURE */
    /*@null@*/void (*wrapup)(struct gps_device_t *session);
    double cycle;
};

struct gps_device_t {
/* session object, encapsulates all global state */
    struct gps_data_t gpsdata;
    /*@relnull@*/struct gps_type_t *device_type;
    struct gps_context_t	*context;
#ifdef ALLOW_RECONFIGURE
    bool enable_reconfigure;		/* OK to hack GPS settings? */ 
#endif /* ALLOW_RECONFIGURE */
    double rtcmtime;	/* timestamp of last RTCM104 correction to GPS */
    struct termios ttyset, ttyset_old;
    unsigned int baudindex;
    int saved_baud;
    struct gps_packet_t packet;
    char subtype[64];			/* firmware version or subtype ID */
    double poll_times[FD_SETSIZE];	/* last daemon poll time */
#ifdef NTPSHM_ENABLE
    int shmindex;
    double last_fixtime;		/* so updates happen once */
# ifdef PPS_ENABLE
    int shmTimeP;
# endif /* PPS_ENABLE */
#endif /* NTPSHM_ENABLE */
    double mag_var;		/* Magnetic variation in degrees */  
    bool back_to_nmea;		/* back to NMEA on revert? */
#ifdef NMEADISC
    int ldisc;			/* current line discipline */
#endif
    /*
     * The rest of this structure is driver-specific private storage.
     * Because the Garmin driver uses a long buffer, you can have
     * up to 4096+12 bytes of private storage in your own union member
     * without making this structure larger or changing the API at all.
     */
    union {