//
// Written by Curtis Olson, started August 1997.
//
-// Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
+// Copyright (C) 1997 Curtis L. Olson - http://www.flightgear.org/~curt
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
#ifdef HAVE_CONFIG_H
-# include <config.h>
+# include <simgear_config.h>
#endif
#include <simgear/compiler.h>
#include <errno.h> // for errno
#ifdef SG_HAVE_STD_INCLUDES
-# include <cmath>
# include <cstdio>
# include <cstdlib>
# include <ctime>
# include <math.h>
# include <stdio.h>
# include <stdlib.h>
-# include <time.h>
#endif
+#include <string>
+
+#ifdef HAVE_SYS_TIME_H
+# include <sys/time.h> // for get/setitimer, gettimeofday, struct timeval
+#endif
#ifdef HAVE_SYS_TIMEB_H
# include <sys/timeb.h> // for ftime() and struct timeb
#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h> // for gettimeofday()
#endif
-#ifdef HAVE_SYS_TIME_H
-# include <sys/time.h> // for get/setitimer, gettimeofday, struct timeval
-#endif
+
+#include <math.h> // for NAN
#include <simgear/constants.h>
#include <simgear/debug/logstream.hxx>
#include "timezone.h"
#include "lowleveltime.h"
-
#define DEGHR(x) ((x)/15.)
#define RADHR(x) DEGHR(x*SGD_RADIANS_TO_DEGREES)
static const double SIDRATE = 0.9972695677;
-SGTime::SGTime( double lon, double lat, const string& root )
+void SGTime::init( double lon_rad, double lat_rad,
+ const string& root, time_t init_time )
{
SG_LOG( SG_EVENT, SG_INFO, "Initializing Time" );
gst_diff = -9999.0;
- cur_time = time(NULL);
- // cout << "Current greenwich mean time = " << asctime(gmtime(&cur_time))
- // << endl;
- // cout << "Current local time = "
- // << asctime(localtime(&cur_time)) << endl;
-
- if ( root != (string)"" ) {
- SGPath zone( root );
- zone.append( "zone.tab" );
- SG_LOG( SG_EVENT, SG_DEBUG, "Reading timezone info from: "
- << zone.str() );
- tzContainer = new TimezoneContainer( zone.c_str() );
-
- GeoCoord location( SGD_RADIANS_TO_DEGREES * lat, SGD_RADIANS_TO_DEGREES * lon );
- GeoCoord* nearestTz = tzContainer->getNearest(location);
-
- SGPath name( root );
- name.append( nearestTz->getDescription() );
- zonename = strdup( name.c_str() );
- // cout << "Using zonename = " << zonename << endl;
+ if ( init_time ) {
+ cur_time = init_time;
} else {
- tzContainer = NULL;
- zonename = NULL;
+ cur_time = time(NULL);
+ }
+
+ SG_LOG( SG_EVENT, SG_INFO,
+ "Current greenwich mean time = " << asctime(gmtime(&cur_time)));
+ SG_LOG( SG_EVENT, SG_INFO,
+ "Current local time = " << asctime(localtime(&cur_time)));
+
+ if ( !root.empty()) {
+ SGPath zone( root );
+ zone.append( "zone.tab" );
+ SG_LOG( SG_EVENT, SG_INFO, "Reading timezone info from: "
+ << zone.str() );
+ tzContainer = new SGTimeZoneContainer( zone.c_str() );
+
+ SGGeoCoord location( SGD_RADIANS_TO_DEGREES * lat_rad, SGD_RADIANS_TO_DEGREES * lon_rad );
+ SGGeoCoord* nearestTz = tzContainer->getNearest(location);
+
+ SGPath name( root );
+ name.append( nearestTz->getDescription() );
+ zonename = name.str();
+ SG_LOG( SG_EVENT, SG_INFO, "Using zonename = " << zonename );
+ } else {
+ SG_LOG( SG_EVENT, SG_INFO, "*** NO TIME ZONE NAME ***" );
+ tzContainer = NULL;
+ zonename.erase();
}
}
+SGTime::SGTime( double lon_rad, double lat_rad, const string& root,
+ time_t init_time )
+{
+ init( lon_rad, lat_rad, root, init_time );
+}
+
SGTime::SGTime( const string& root ) {
- SGTime( 0.0, 0.0, root );
+ init( 0.0, 0.0, root, 0 );
}
SGTime::SGTime() {
- SGTime( 0.0, 0.0, "" );
+ init( 0.0, 0.0, "", 0 );
}
SGTime::~SGTime()
{
if ( tzContainer != NULL ) {
- delete tzContainer;
- }
-
- if ( zonename != NULL ) {
- delete zonename;
+ SGTimeZoneContainer *tmp = tzContainer;
+ tzContainer = NULL;
+ delete tmp;
}
}
// return a courser but cheaper estimate of sidereal time
-static double sidereal_course( time_t cur_time, struct tm *gmt, double lng )
+static double sidereal_course( time_t cur_time, const struct tm *gmt, double lng )
{
time_t start_gmt, now;
double diff, part, days, hours, lstTmp;
// Update the time related variables
-void SGTime::update( double lon, double lat, long int warp ) {
+void SGTime::update( double lon_rad, double lat_rad,
+ time_t ct, long int warp )
+{
double gst_precise, gst_course;
+#if defined(_MSC_VER) || defined(__MINGW32__)
+ tm * gmt = &m_gmt;
+#endif
+
SG_LOG( SG_EVENT, SG_DEBUG, "Updating time" );
// get current Unix calendar time (in seconds)
// warp += warp_delta;
- cur_time = time(NULL) + warp;
+ if ( ct ) {
+ cur_time = ct + warp;
+ } else {
+ cur_time = time(NULL) + warp;
+ }
SG_LOG( SG_EVENT, SG_DEBUG,
" Current Unix calendar time = " << cur_time
<< " warp = " << warp );
// get GMT break down for current time
+#if defined(_MSC_VER) || defined(__MINGW32__)
+ memcpy( gmt, gmtime(&cur_time), sizeof(tm) );
+#else
gmt = gmtime(&cur_time);
+#endif
SG_LOG( SG_EVENT, SG_DEBUG,
" Current GMT = " << gmt->tm_mon+1 << "/"
- << gmt->tm_mday << "/" << gmt->tm_year << " "
+ << gmt->tm_mday << "/" << (1900 + gmt->tm_year) << " "
<< gmt->tm_hour << ":" << gmt->tm_min << ":"
<< gmt->tm_sec );
- // calculate modified Julian date
- // t->mjd = cal_mjd ((int)(t->gmt->tm_mon+1), (double)t->gmt->tm_mday,
- // (int)(t->gmt->tm_year + 1900));
- mjd = sgTimeCalcMJD( (int)(gmt->tm_mon+1), (double)gmt->tm_mday,
- (int)(gmt->tm_year + 1900) );
+ // calculate modified Julian date starting with current
+ mjd = sgTimeCurrentMJD( ct, warp );
// add in partial day
mjd += (gmt->tm_hour / 24.0) + (gmt->tm_min / (24.0 * 60.0)) +
gst_diff = gst_precise - gst_course;
- lst = sidereal_course( cur_time, gmt, -(lon * SGD_RADIANS_TO_DEGREES) ) + gst_diff;
+ lst = sidereal_course( cur_time, gmt,
+ -(lon_rad * SGD_RADIANS_TO_DEGREES) ) + gst_diff;
} else {
// course + difference should drift off very slowly
gst = sidereal_course( cur_time, gmt, 0.00 ) + gst_diff;
- lst = sidereal_course( cur_time, gmt, -(lon * SGD_RADIANS_TO_DEGREES) ) + gst_diff;
+ lst = sidereal_course( cur_time, gmt,
+ -(lon_rad * SGD_RADIANS_TO_DEGREES) ) + gst_diff;
}
SG_LOG( SG_EVENT, SG_DEBUG,
" Current lon=0.00 Sidereal Time = " << gst );
SG_LOG( SG_EVENT, SG_DEBUG,
" Current LOCAL Sidereal Time = " << lst << " ("
- << sidereal_precise( mjd, -(lon * SGD_RADIANS_TO_DEGREES) )
+ << sidereal_precise( mjd, -(lon_rad * SGD_RADIANS_TO_DEGREES) )
<< ") (diff = " << gst_diff << ")" );
}
// Given lon/lat, update timezone information and local_offset
-void SGTime::updateLocal( double lon, double lat, const string& root )
-{
- time_t currGMT;
- time_t aircraftLocalTime;
- GeoCoord location( SGD_RADIANS_TO_DEGREES * lat, SGD_RADIANS_TO_DEGREES * lon );
- GeoCoord* nearestTz = tzContainer->getNearest(location);
- SGPath zone( root );
- zone.append ( nearestTz->getDescription() );
- if ( zonename ) {
- delete zonename;
- }
- zonename = strdup( zone.c_str() );
- currGMT = sgTimeGetGMT( gmtime(&cur_time) );
- aircraftLocalTime = sgTimeGetGMT( (fgLocaltime(&cur_time, zone.c_str())) );
- local_offset = aircraftLocalTime - currGMT;
- // cout << "Using " << local_offset << " as local time offset Timezone is "
- // << zonename << endl;
+void SGTime::updateLocal( double lon_rad, double lat_rad, const string& root ) {
+ // sanity checking
+ if ( lon_rad < -SGD_PI || lon_rad> SGD_PI ) {
+ // not within -180 ... 180
+ lon_rad = 0.0;
+ }
+ if ( lat_rad < -SGD_PI * 0.5 || lat_rad > SGD_PI * 0.5 ) {
+ // not within -90 ... 90
+ lat_rad = 0.0;
+ }
+ if ( lon_rad != lon_rad ) {
+ // only true if lon_rad == nan
+ SG_LOG( SG_EVENT, SG_ALERT,
+ " Detected lon_rad == nan, resetting to 0.0" );
+ lon_rad = 0.0;
+ }
+ if ( lat_rad != lat_rad ) {
+ // only true if lat_rad == nan
+ SG_LOG( SG_EVENT, SG_ALERT,
+ " Detected lat_rad == nan, resetting to 0.0" );
+ lat_rad = 0.0;
+ }
+ time_t currGMT;
+ time_t aircraftLocalTime;
+ SGGeoCoord location( SGD_RADIANS_TO_DEGREES * lat_rad,
+ SGD_RADIANS_TO_DEGREES * lon_rad );
+ SGGeoCoord* nearestTz = tzContainer->getNearest(location);
+ SGPath zone( root );
+ zone.append ( nearestTz->getDescription() );
+ zonename = zone.str();
+
+ //Avoid troubles when zone.tab hasn't got the right line endings
+ if (zonename[zonename.size()-1] == '\r')
+ {
+ zonename[zonename.size()-1]=0;
+ zone.set( zonename );
+ }
+
+ currGMT = sgTimeGetGMT( gmtime(&cur_time) );
+ aircraftLocalTime = sgTimeGetGMT( (fgLocaltime(&cur_time, zone.c_str())) );
+ local_offset = aircraftLocalTime - currGMT;
+ // cout << "Using " << local_offset << " as local time offset Timezone is "
+ // << zonename << endl;
}
}
+// return the current modified Julian date (number of days elapsed
+// since 1900 jan 0.5), mjd.
+double sgTimeCurrentMJD( time_t ct, long int warp ) {
+
+#if defined(_MSC_VER) || defined(__MINGW32__)
+ struct tm m_gmt; // copy of system gmtime(&time_t) structure
+ struct tm *gmt = &m_gmt;
+#else
+ struct tm *gmt;
+#endif
+
+ // get current Unix calendar time (in seconds)
+ // warp += warp_delta;
+ time_t cur_time;
+ if ( ct ) {
+ cur_time = ct + warp;
+ } else {
+ cur_time = time(NULL) + warp;
+ }
+ SG_LOG( SG_EVENT, SG_DEBUG,
+ " Current Unix calendar time = " << cur_time
+ << " warp = " << warp );
+
+ // get GMT break down for current time
+#if defined(_MSC_VER) || defined(__MINGW32__)
+ memcpy( gmt, gmtime(&cur_time), sizeof(tm) );
+#else
+ gmt = gmtime(&cur_time);
+#endif
+ SG_LOG( SG_EVENT, SG_DEBUG,
+ " Current GMT = " << gmt->tm_mon+1 << "/"
+ << gmt->tm_mday << "/" << (1900 + gmt->tm_year) << " "
+ << gmt->tm_hour << ":" << gmt->tm_min << ":"
+ << gmt->tm_sec );
+
+ // calculate modified Julian date
+ // t->mjd = cal_mjd ((int)(t->gmt->tm_mon+1), (double)t->gmt->tm_mday,
+ // (int)(t->gmt->tm_year + 1900));
+ double mjd = sgTimeCalcMJD( (int)(gmt->tm_mon+1), (double)gmt->tm_mday,
+ (int)(gmt->tm_year + 1900) );
+
+ return mjd;
+}
+
+
// given an mjd, calculate greenwich mean sidereal time, gst
double sgTimeCalcGST( double mjd ) {
double gst;
return ( timegm(&mt) );
#elif defined( MK_TIME_IS_GMT )
time_t ret = mktime(&mt);
+
+#ifdef __CYGWIN__
+ ret -= _timezone;
+#endif
+
// This is necessary as some mktime() calls may
// try to access the system timezone files
// if this open fails errno is set to 2
// CYGWIN for one does this
- if ( errno ) {
- perror( "sgTimeGetGMT()" );
- errno = 0;
- }
+ // if ( errno ) {
+ // perror( "sgTimeGetGMT()" );
+ // errno = 0;
+ // }
+
+ // reset errno in any event.
+ errno = 0;
+
return ret;
#else // ! defined ( MK_TIME_IS_GMT )
// timezone seems to work as a proper offset for Linux & Solaris
-# if defined( __linux__ ) || defined( __sun__ )
+# if defined( __linux__ ) || defined( __sun__ ) ||defined(__CYGWIN__)
# define TIMEZONE_OFFSET_WORKS 1
# endif
+#if defined(__CYGWIN__)
+#define TIMEZONE _timezone
+#else
+#define TIMEZONE timezone
+#endif
+
time_t start = mktime(&mt);
SG_LOG( SG_EVENT, SG_DEBUG, "start1 = " << start );
// fgPrintf( SG_EVENT, SG_DEBUG, "start2 = %s", ctime(&start));
SG_LOG( SG_EVENT, SG_DEBUG, "(tm_isdst = " << mt.tm_isdst << ")" );
- timezone = fix_up_timezone( timezone );
+ TIMEZONE = fix_up_timezone( TIMEZONE );
# if defined( TIMEZONE_OFFSET_WORKS )
SG_LOG( SG_EVENT, SG_DEBUG,
- "start = " << start << ", timezone = " << timezone );
- return( start - timezone );
+ "start = " << start << ", timezone = " << TIMEZONE );
+ return( start - TIMEZONE );
# else // ! defined( TIMEZONE_OFFSET_WORKS )
daylight = mt.tm_isdst;
"OOOPS, problem in sg_time.cxx, no daylight savings info." );
}
- long int offset = -(timezone / 3600 - daylight);
+ long int offset = -(TIMEZONE / 3600 - daylight);
- SG_LOG( SG_EVENT, SG_DEBUG, " Raw time zone offset = " << timezone );
+ SG_LOG( SG_EVENT, SG_DEBUG, " Raw time zone offset = " << TIMEZONE );
SG_LOG( SG_EVENT, SG_DEBUG, " Daylight Savings = " << daylight );
SG_LOG( SG_EVENT, SG_DEBUG, " Local hours from GMT = " << offset );
- long int start_gmt = start - timezone + (daylight * 3600);
+ long int start_gmt = start - TIMEZONE + (daylight * 3600);
SG_LOG( SG_EVENT, SG_DEBUG, " March 21 noon (CST) = " << start );