//
// 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
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Library General Public License for more details.
//
-// You should have received a copy of the GNU Library General Public
-// License along with this library; if not, write to the
-// Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-// Boston, MA 02111-1307, USA.
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
//
// $Id$
#ifdef HAVE_CONFIG_H
-# include <config.h>
+# include <simgear_config.h>
#endif
#include <simgear/compiler.h>
-#ifdef FG_HAVE_STD_INCLUDES
-# include <cmath>
-# include <cstdio>
-# include <cstdlib>
-# include <ctime>
-#else
-# include <math.h>
-# include <stdio.h>
-# include <stdlib.h>
-# include <time.h>
-#endif
+#include <errno.h> // for errno
+
+#include <cstdio>
+#include <cstdlib>
+#include <ctime>
+#include <cstring>
+#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 <simgear/misc/fgpath.hxx>
+#include <simgear/misc/sg_path.hxx>
#include "sg_time.hxx"
#include "timezone.h"
#include "lowleveltime.h"
-
#define DEGHR(x) ((x)/15.)
-#define RADHR(x) DEGHR(x*RAD_TO_DEG)
+#define RADHR(x) DEGHR(x*SGD_RADIANS_TO_DEGREES)
+using std::string;
-SGTime::SGTime( double lon, double lat, const string& root )
-{
- FG_LOG( FG_EVENT, FG_INFO, "Initializing Time" );
+static const double MJD0 = 2415020.0;
+static const double J2000 = 2451545.0 - MJD0;
+static const double SIDRATE = 0.9972695677;
+
+// tzContainer stores all the current Timezone control points/
+std::auto_ptr<SGTimeZoneContainer> static_tzContainer;
+void SGTime::init( const SGGeod& location, const SGPath& root, time_t init_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 != "" ) {
- FGPath zone( root );
- zone.append( "zone.tab" );
- FG_LOG( FG_EVENT, FG_DEBUG, "Reading timezone info from: "
- << zone.str() );
- tzContainer = new TimezoneContainer( zone.c_str() );
-
- GeoCoord location( RAD_TO_DEG * lat, RAD_TO_DEG * lon );
- GeoCoord* nearestTz = tzContainer->getNearest(location);
-
- FGPath name( root );
- name.append( nearestTz->getDescription() );
- zonename = strdup( name.c_str() );
- // cout << "Using zonename = " << zonename << endl;
+ if ( init_time ) {
+ cur_time = init_time;
+ } else {
+ cur_time = time(NULL);
+ }
+
+ SG_LOG( SG_EVENT, SG_DEBUG,
+ "Current greenwich mean time = " << asctime(gmtime(&cur_time)));
+ SG_LOG( SG_EVENT, SG_DEBUG,
+ "Current local time = " << asctime(localtime(&cur_time)));
+
+ if ( !root.isNull()) {
+ if (!static_tzContainer.get()) {
+ SGPath zone( root );
+ zone.append( "zone.tab" );
+ SG_LOG( SG_EVENT, SG_INFO, "Reading timezone info from: "
+ << zone.str() );
+ static_tzContainer.reset(new SGTimeZoneContainer( zone.c_str() ));
+ }
+
+ SGTimeZone* nearestTz = static_tzContainer->getNearest(location);
+
+ SGPath name( root );
+ name.append( nearestTz->getDescription() );
+ zonename = name.str();
+ SG_LOG( SG_EVENT, SG_DEBUG, "Using zonename = " << zonename );
} else {
- tzContainer = NULL;
- zonename = NULL;
+ zonename.erase();
}
}
+SGTime::SGTime( const SGGeod& location, const SGPath& root,
+ time_t init_time )
+{
+ init(location, root, init_time);
+}
-SGTime::SGTime( const string& root ) {
- SGTime( 0.0, 0.0, root );
+SGTime::SGTime( const SGPath& root ) {
+ init( SGGeod(), root, 0 );
}
SGTime::SGTime() {
- SGTime( 0.0, 0.0, "" );
+ init( SGGeod(), SGPath(), 0 );
}
SGTime::~SGTime()
{
- if ( tzContainer != NULL ) {
- delete tzContainer;
- }
-
- if ( zonename != NULL ) {
- delete zonename;
- }
}
mjd + MJD0, lng); */
// convert to required internal units
- lng *= DEG_TO_RAD;
+ lng *= SGD_DEGREES_TO_RADIANS;
// compute LST and print
double gst = sgTimeCalcGST( mjd );
// 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;
- char tbuf[64];
now = cur_time;
start_gmt = sgTimeGetGMT(gmt->tm_year, 2, 21, 12, 0, 0);
- FG_LOG( FG_EVENT, FG_DEBUG, " COURSE: GMT = "
- << sgTimeFormatTime(gmt, tbuf) );
- FG_LOG( FG_EVENT, FG_DEBUG, " March 21 noon (GMT) = " << start_gmt );
-
diff = (now - start_gmt) / (3600.0 * 24.0);
- FG_LOG( FG_EVENT, FG_DEBUG,
- " Time since 3/21/" << gmt->tm_year << " GMT = " << diff );
-
part = fmod(diff, 1.0);
days = diff - part;
hours = gmt->tm_hour + gmt->tm_min/60.0 + gmt->tm_sec/3600.0;
while ( lstTmp < 0.0 ) {
lstTmp += 24.0;
}
-
- FG_LOG( FG_EVENT, FG_DEBUG,
- " days = " << days << " hours = " << hours << " lon = "
- << lng << " lst = " << lstTmp );
-
+
return lstTmp;
}
-
// Update the time related variables
-void SGTime::update( double lon, double lat, long int warp ) {
+void SGTime::update( const SGGeod& location, time_t ct, long int warp )
+{
double gst_precise, gst_course;
- FG_LOG( FG_EVENT, FG_DEBUG, "Updating time" );
+
+ tm * gmt = &m_gmt;
+
// get current Unix calendar time (in seconds)
// warp += warp_delta;
- cur_time = time(NULL) + warp;
- FG_LOG( FG_EVENT, FG_DEBUG,
- " Current Unix calendar time = " << cur_time
- << " warp = " << warp );
+ if ( ct ) {
+ cur_time = ct + warp;
+ } else {
+ cur_time = time(NULL) + warp;
+ }
// get GMT break down for current time
- gmt = gmtime(&cur_time);
- FG_LOG( FG_EVENT, FG_DEBUG,
- " Current GMT = " << gmt->tm_mon+1 << "/"
- << gmt->tm_mday << "/" << 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) );
+ memcpy( gmt, gmtime(&cur_time), sizeof(tm) );
+ // 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)) +
// convert "back" to Julian date + partial day (as a fraction of one)
jd = mjd + MJD0;
- FG_LOG( FG_EVENT, FG_DEBUG, " Current Julian Date = " << jd );
- // printf(" Current Longitude = %.3f\n", FG_Longitude * RAD_TO_DEG);
+ // printf(" Current Longitude = %.3f\n", FG_Longitude * SGD_RADIANS_TO_DEGREES);
// Calculate local side real time
if ( gst_diff < -100.0 ) {
// first time through do the expensive calculation & cheap
// calculation to get the difference.
- FG_LOG( FG_EVENT, FG_INFO, " First time, doing precise gst" );
+ SG_LOG( SG_EVENT, SG_DEBUG, " First time, doing precise gst" );
gst_precise = gst = sidereal_precise( mjd, 0.00 );
gst_course = sidereal_course( cur_time, gmt, 0.00 );
gst_diff = gst_precise - gst_course;
- lst = sidereal_course( cur_time, gmt, -(lon * RAD_TO_DEG) ) + gst_diff;
+ lst = sidereal_course( cur_time, gmt,
+ -location.getLongitudeDeg() ) + 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 * RAD_TO_DEG) ) + gst_diff;
+ lst = sidereal_course( cur_time, gmt,
+ -location.getLongitudeDeg() ) + gst_diff;
}
-
- FG_LOG( FG_EVENT, FG_DEBUG,
- " Current lon=0.00 Sidereal Time = " << gst );
- FG_LOG( FG_EVENT, FG_DEBUG,
- " Current LOCAL Sidereal Time = " << lst << " ("
- << sidereal_precise( mjd, -(lon * RAD_TO_DEG) )
- << ") (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( RAD_TO_DEG * lat, RAD_TO_DEG * lon );
- GeoCoord* nearestTz = tzContainer->getNearest(location);
- FGPath 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( const SGGeod& aLocation, const string& root ) {
+ SGGeod location(aLocation);
+ if (!aLocation.isValid()) {
+ location = SGGeod();
+ }
+
+ time_t currGMT;
+ time_t aircraftLocalTime;
+ SGTimeZone* nearestTz = static_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 ) {
+
+ struct tm m_gmt; // copy of system gmtime(&time_t) structure
+ struct tm *gmt = &m_gmt;
+
+ // 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;
+ }
+
+ // get GMT break down for current time
+ memcpy( gmt, gmtime(&cur_time), sizeof(tm) );
+
+ // 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;
x /= 3600.0;
gst = (1.0/SIDRATE)*hr + x;
- FG_LOG( FG_EVENT, FG_DEBUG, " gst => " << gst );
-
return gst;
}
# define MK_TIME_IS_GMT 1
#endif
-#if defined( HAVE_TIMEGM )
+#if defined( HAVE_TIMEGM )
return ( timegm(&mt) );
#elif defined( MK_TIME_IS_GMT )
- return ( mktime(&mt) );
+ 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;
+ // }
+
+ // 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
- long int start = mktime(&mt);
+#if defined(__CYGWIN__)
+#define TIMEZONE _timezone
+#else
+#define TIMEZONE timezone
+#endif
+
+ time_t start = mktime(&mt);
- FG_LOG( FG_EVENT, FG_DEBUG, "start1 = " << start );
+ SG_LOG( SG_EVENT, SG_DEBUG, "start1 = " << start );
// the ctime() call can screw up time progression on some versions
// of Linux
- // fgPrintf( FG_EVENT, FG_DEBUG, "start2 = %s", ctime(&start));
- FG_LOG( FG_EVENT, FG_DEBUG, "(tm_isdst = " << mt.tm_isdst << ")" );
+ // 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 )
- FG_LOG( FG_EVENT, FG_DEBUG,
- "start = " << start << ", timezone = " << timezone );
- return( start - timezone );
+ SG_LOG( SG_EVENT, SG_DEBUG,
+ "start = " << start << ", timezone = " << TIMEZONE );
+ return( start - TIMEZONE );
# else // ! defined( TIMEZONE_OFFSET_WORKS )
daylight = mt.tm_isdst;
if ( daylight > 0 ) {
daylight = 1;
} else if ( daylight < 0 ) {
- FG_LOG( FG_EVENT, FG_WARN,
+ SG_LOG( SG_EVENT, SG_WARN,
"OOOPS, problem in sg_time.cxx, no daylight savings info." );
}
- long int offset = -(timezone / 3600 - daylight);
+ long int offset = -(TIMEZONE / 3600 - daylight);
- FG_LOG( FG_EVENT, FG_DEBUG, " Raw time zone offset = " << timezone );
- FG_LOG( FG_EVENT, FG_DEBUG, " Daylight Savings = " << daylight );
- FG_LOG( FG_EVENT, FG_DEBUG, " Local hours from GMT = " << offset );
+ 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);
- FG_LOG( FG_EVENT, FG_DEBUG, " March 21 noon (CST) = " << start );
+ SG_LOG( SG_EVENT, SG_DEBUG, " March 21 noon (CST) = " << start );
return ( start_gmt );
# endif // ! defined( TIMEZONE_OFFSET_WORKS )
projects / simgear.git / blobdiff