/** Represents the standard GPS interface. */
typedefstruct{
/**
* Opens the interface and provides the callback routines
* to the implemenation of this interface.
*/
int(*init)(GpsCallbacks*callbacks);
/** Starts navigating. */
int(*start)(void);
/** Stops navigating. */
int(*stop)(void);
/** Closes the interface. */
void(*cleanup)(void);
/** Injects the current time. */
int(*inject_time)(GpsUtcTimetime,int64_ttimeReference,
intuncertainty);
/** Injects current location from another location provider
* (typically cell ID).
* latitude and longitude are measured in degrees
* expected accuracy is measured in meters
*/
int(*inject_location)(doublelatitude,doublelongitude,floataccuracy);
/**
* Specifies that the next call to start will not use the
* information defined in the flags. GPS_DELETE_ALL is passed for
* a cold start.
*/
void(*delete_aiding_data)(GpsAidingData flags);
/**
* fix_frequency represents the time between fixes in seconds.
* Set fix_frequency to zero for a single-shot fix.
*/
int(*set_position_mode)(GpsPositionMode mode,intfix_frequency);
/** Get a pointer to extension information. */
constvoid*(*get_extension)(constchar*name);
}GpsInterface;


/** GPS callback structure. */
typedefstruct{
gps_location_callback location_cb;
gps_status_callback status_cb;
gps_sv_status_callback sv_status_cb;
gps_nmea_callback nmea_cb;
}GpsCallbacks;
/** Callback with location information. */
typedefvoid(*gps_location_callback)(GpsLocation*location);
/** Callback with status information. */
typedefvoid(*gps_status_callback)(GpsStatus*status);
/** Callback with SV status information. */
typedefvoid(*gps_sv_status_callback)(GpsSvStatus*sv_info);
/** Callback for reporting NMEA sentences. */
typedefvoid(*gps_nmea_callback)(GpsUtcTime timestamp,constchar*nmea,intlength);


/** Represents a location. */
typedefstruct{
/** Contains GpsLocationFlags bits. */
uint16_tflags;
/** Represents latitude in degrees. */
doublelatitude;
/** Represents longitude in degrees. */
doublelongitude;
/** Represents altitude in meters above the WGS 84 reference
* ellipsoid. */
doublealtitude;
/** Represents speed in meters per second. */
floatspeed;
/** Represents heading in degrees. */
floatbearing;
/** Represents expected accuracy in meters. */
floataccuracy;
/** Timestamp for the location fix. */
GpsUtcTime timestamp;
}GpsLocation;