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[Plplot-cvs] SF.net SVN: plplot:[9564] trunk
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From: <ai...@us...> - 2009-02-20 19:43:17
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Revision: 9564
http://plplot.svn.sourceforge.net/plplot/?rev=9564&view=rev
Author: airwin
Date: 2009-02-20 19:43:15 +0000 (Fri, 20 Feb 2009)
Log Message:
-----------
Convert to a thread-safe libqsastime where qsasconfig is carried as an extra
argument to configqsas, closeqsas, btimeqsas, ctimeqsas, and strfqsas rather
than as a global library variable. Thanks to Andrew Ross for this
suggestiong for making libqsastime thread safe.
Modified Paths:
--------------
trunk/lib/qsastime/README.qsastime_API
trunk/lib/qsastime/qsastime.c
trunk/lib/qsastime/qsastime.h
trunk/src/plbox.c
Modified: trunk/lib/qsastime/README.qsastime_API
===================================================================
--- trunk/lib/qsastime/README.qsastime_API 2009-02-20 19:38:15 UTC (rev 9563)
+++ trunk/lib/qsastime/README.qsastime_API 2009-02-20 19:43:15 UTC (rev 9564)
@@ -1,10 +1,11 @@
-The desired API for libqsastime should consist of just five functions that
-are actually publicly visible. The names of these five functions are
-subject to change, but I hope we can finalize those names shortly.
+The desired API for libqsastime should consist of just five functions
+that are actually publicly visible.
=========================
-void configqsas(double scale, double offset1, double offset2, int ccontrol, int ifbtime_offset, int year, int month, int day, int hour, int min, double sec);
+void configqsas(double scale, double offset1, double offset2, int
+ccontrol, int ifbtime_offset, int year, int month, int day, int hour,
+int min, double sec, QSASCONFIG **qsasconfig);
Within this routine if ifbtime_offset is false, then the broken-down
time arguments are ignored. If ifbtime_offset is true, then the input
@@ -12,17 +13,20 @@
time values are used to calculate offset1 and offset2 with the help of
an internal call to setFromUT.
-This routine allocates memory for the global qsasconfig pointer to
-a QSASConfig struct. It initializes the four variables encapsulated
-in QSASConfig with scale, offset1, offset2, and ccontrol. Further
-details of the meaning of these four variables is contained in
-qsastime.h.
+If *qsasconfig is NULL, this routine allocates memory for a QSASCONFIG
+struct and points *qsaconfig to that memory location. It initializes
+the four variables encapsulated in that struct with scale, offset1,
+offset2, and ccontrol. Further details of the meaning of these four
+variables is contained in qsastime.h. The special pointer to a
+pointer QSASCONFIG argument is required so that the external pointer
+can be changed if/when the memory is allocated.
-Although this API gives the user a large degree of flexibility in choosing
-the transformation between broken-down time and continuous time, a number of
-combinations of offset1, offset2, scale, and ccontrol are documented
-below for some common time system transformations to guide the user.
-(Some of these are currently just placeholders.)
+Although this API gives the user a large degree of flexibility in
+choosing the transformation between broken-down time and continuous
+time, a number of combinations of offset1, offset2, scale, and
+ccontrol are documented below for some common time system
+transformations to guide the user. (Some of these are currently just
+placeholders.)
Broken- Contin- offset1 offset2 scale correction Notes
down uous
@@ -39,76 +43,87 @@
1. These offset1, offset2, scale, and correction values are the
library default if the user does not call time_config at all.
-2. We define civil time as the civil time on the prime meridian. (The user
-is responsible for converting their local time to civil time using their
-locale data for time zone and daylight savings time adjustment). Currently,
-our civil time corresponds to UTC as defined in note 3.
+2. We define civil time as the civil time on the prime meridian. (The
+user is responsible for converting their local time to civil time
+using their locale data for time zone and daylight savings time
+adjustment). Currently, our civil time corresponds to UTC as defined
+in note 3.
-3. We use the file at http://maia.usno.navy.mil/ser7/tai-utc.dat to define
-the relationship between UTC and TAI (and thus TT) for correction = 1.
+3. We use the file at http://maia.usno.navy.mil/ser7/tai-utc.dat to
+define the relationship between UTC and TAI (and thus TT) for
+correction = 1.
For epochs prior to the starting date of that file (1961-01-01 = JD
-2437300.5 UTC) we assume the same TAI-UTC offset of 1.422818 seconds as for
-the starting date of that file. This assumption of no variation in the
-earth rotation rate prior to 1961 is obviously not correct so that the TT
-derived from our code will not be reliable prior to that date. That is, if
-you use GMT (a historical backwards extension of UTC corresponding to civil
-time for the prime meridian) for broken down time prior to 1961, the TT
-result you will get will not produce a good approximation to the historical
-ephemeris time that is the correct backwards extension of TT, see
-http://en.wikipedia.org/wiki/Ephemeris_time.
+2437300.5 UTC) we assume the same TAI-UTC offset of 1.422818 seconds
+as for the starting date of that file. This assumption of no
+variation in the earth rotation rate prior to 1961 is obviously not
+correct so that the TT derived from our code will not be reliable
+prior to that date. That is, if you use GMT (a historical backwards
+extension of UTC corresponding to civil time for the prime meridian)
+for broken down time prior to 1961, the TT result you will get will
+not produce a good approximation to the historical ephemeris time that
+is the correct backwards extension of TT, see
+http://en.wikipedia.org/wiki/Ephemeris_time.
-For epochs after the ending date of that file (currently 2009-01-01 = JD
-2454832.5 UTC) we assume the same TAI-UTC offset (currently 34 seconds) as
-for the ending date of that file, i.e., we assume no leap seconds after the
-ending date of the file. Insertion of leap seconds cannot be predicted years
-in advance (because future predictions of the earth rotation rate are not
-reliable on such time scales) so the transformation between civil time (UTC)
-and TT cannot be known years in advance. However, the approximation of
-assuming no leap seconds after the end of the file should be correct on time
-scales less than roughly a year so when a decision is made in advance to
-insert an official leap second, there should be plenty of time for that
-decision to propagate to http://maia.usno.navy.mil/ser7/tai-utc.dat and
-ultimately our code releases. Thus, so long as we make releases on a timely
-basis, our calculation of TT for current epochs should always be reliable.
+For epochs after the ending date of that file (currently 2009-01-01 =
+JD 2454832.5 UTC) we assume the same TAI-UTC offset (currently 34
+seconds) as for the ending date of that file, i.e., we assume no leap
+seconds after the ending date of the file. Insertion of leap seconds
+cannot be predicted years in advance (because future predictions of
+the earth rotation rate are not reliable on such time scales) so the
+transformation between civil time (UTC) and TT cannot be known years
+in advance. However, the approximation of assuming no leap seconds
+after the end of the file should be correct on time scales less than
+roughly a year so when a decision is made in advance to insert an
+official leap second, there should be plenty of time for that decision
+to propagate to http://maia.usno.navy.mil/ser7/tai-utc.dat and
+ultimately our code releases. Thus, so long as we make releases on a
+timely basis, our calculation of TT for current epochs should always
+be reliable.
-2. I haven't checked the code yet, but I assume this relationship holds for
-all transformations between broken-down time and continuous time in MJD
-when the broken-down time and continuous time are defined on the same
-continuous time scale (TT in this case). All other relationships are
-derived from the known offsets with respect to TT and differences between
-MJD epochs and native (TT, TAI, etc.) epochs.
+2. I haven't checked the code yet, but I assume this relationship
+holds for all transformations between broken-down time and continuous
+time in MJD when the broken-down time and continuous time are defined
+on the same continuous time scale (TT in this case). All other
+relationships are derived from the known offsets with respect to TT
+and differences between MJD epochs and native (TT, TAI, etc.) epochs.
-3. Offset derived from definition TT = TAI + 32.184 s = TAI + 0.0003725 d
+3. Offset derived from definition TT = TAI + 32.184 s = TAI +
+0.0003725 d
-4. Continuous times (e.g., TT) without further designation are in seconds
-since the native (e.g., TT) epoch. NEEDS WORK to figure out offset.
+4. Continuous times (e.g., TT) without further designation are in
+seconds since the native (e.g., TT) epoch. NEEDS WORK to figure out
+offset.
5. the POSIX time standard of seconds since the Unix epoch is actually
-discontinuous (see remarks in http://en.wikipedia.org/wiki/Unix_Time). So
-our "Unix (TAI)" continuous time scale (NOT YET IN THE TABLE) corresponds to
-the continuous "International Atomic Time-based variant" discussed in the
-above article. NEEDS FURTHER INVESTIGATION.
+discontinuous (see remarks in http://en.wikipedia.org/wiki/Unix_Time).
+So our "Unix (TAI)" continuous time scale (NOT YET IN THE TABLE)
+corresponds to the continuous "International Atomic Time-based
+variant" discussed in the above article. NEEDS FURTHER INVESTIGATION.
-dTT/dTCG = 1-LG, where LG = 6.969290134D-10,
-IAU Resolution B1.9 Re-definition of Terrestrial Time TT,
+dTT/dTCG = 1-LG, where LG = 6.969290134D-10, IAU Resolution B1.9
+Re-definition of Terrestrial Time TT,
http://syrte.obspm.fr/IAU_resolutions/Resol-UAI.htm
-Time ephemeris reference is Irwin and
-Fukushima, 1999, http://adsabs.harvard.edu/full/1999A&A...348..642I).
+Time ephemeris reference is Irwin and Fukushima, 1999,
+http://adsabs.harvard.edu/full/1999A&A...348..642I).
=========================
-void closeqsas (void):
+void closeqsas (QSASCONFIG **qsasconfig):
-Closes library by freeing memory allocated for qsasconfig.
+This routine closes the library by freeing memory allocated for
+qsasconfig if *qsaconfig is non-NULL and sets *qsasconfig to NULL.
+The special pointer to a pointer QSASCONFIG argument is required in
+order to change the external pointer.
+
=========================
void ctimeqsas (int year, int month, int day, int hour, int min,
-double sec, double *ctime);
+double sec, double *ctime, QSASCONFIG *qsasconfig);
Determine continuous time (ctime). Wraps the existing internal (not
-visible by default) setFromUT to use the four global variables
+visible by default) setFromUT to use the four variables in qsasconfig
discussed above in the transformation from broken-down-time to ctime.
Note, because of the transformation implied by the four variables
mentioned above, the ctime result can be stored in just a double
@@ -119,26 +134,28 @@
=========================
void btimeqsas (int *year, int *month, int *day, int *hour, int *min,
-double *sec, double ctime);
+double *sec, double ctime, QSASCONFIG *qsasconfig);
-Determine broken-down time (btime). This is the inverse of ctimeqsas. It
-wraps the existing internal (not visible by default) breakDownMJD to use the
-four global variables discussed above in the transformation from ctime to
-btime. Note, because of the transformation implied by the four variables
-mentioned above, the input ctime can be just a double assuming the user has
-picked a reasonable epoch that is not so distant from his plotted range of
-times that it causes a noticable loss of numerical precision.
+Determine broken-down time (btime). This is the inverse of ctimeqsas.
+It wraps the existing internal (not visible by default) breakDownMJD
+to use the four variables in qsasconfig discussed above in the
+transformation from ctime to btime. Note, because of the
+transformation implied by the four variables, the input ctime can be
+just a double assuming the user has picked a reasonable epoch that is
+not so distant from his plotted range of times that it causes a
+noticable loss of numerical precision.
=========================
-size_t strfqsas (char * buf, size_t len, const char * format, const
-double ctime);
+size_t strfqsas (char * buf, size_t len, const char * format, const
+double ctime, QSASCONFIG *qsasconfig);
-This wraps the existing internal (not visible by default) strfMJD to use the
-four global variables discussed above in the transformation from ctime to
-btime. Note, because of the transformation implied by the four variables
-mentioned above, the input ctime can be just a double assuming the user has
-picked a reasonable epoch that is not so distant from his plotted range of
-times that it causes a noticable loss of numerical precision.
+This wraps the existing internal (not visible by default) strfMJD to
+use the four variables in qsasconfig discussed above in the
+transformation from ctime to btime. Note, because of the
+transformation implied by the four variables, the input ctime can be
+just a double assuming the user has picked a reasonable epoch that is
+not so distant from his plotted range of times that it causes a
+noticable loss of numerical precision.
=========================
Modified: trunk/lib/qsastime/qsastime.c
===================================================================
--- trunk/lib/qsastime/qsastime.c 2009-02-20 19:38:15 UTC (rev 9563)
+++ trunk/lib/qsastime/qsastime.c 2009-02-20 19:43:15 UTC (rev 9564)
@@ -859,18 +859,18 @@
return posn;
}
-void configqsas(double scale, double offset1, double offset2, int ccontrol, int ifbtime_offset, int year, int month, int day, int hour, int min, double sec)
+void configqsas(double scale, double offset1, double offset2, int ccontrol, int ifbtime_offset, int year, int month, int day, int hour, int min, double sec, QSASConfig **qsasconfig)
{
/* Configure the transformation between continuous time and broken-down time
that is used for ctimeqsas, btimeqsas, and strfqsas. */
int forceJulian, ret;
MJDtime MJD_value, *MJD=&MJD_value;
- /* Allocate memory for qsasconfig if that hasn't been done by a
+ /* Allocate memory for *qsasconfig if that hasn't been done by a
previous call. */
- if(qsasconfig == NULL) {
- qsasconfig = (QSASConfig *) malloc((size_t) sizeof(QSASConfig));
- if (qsasconfig == NULL) {
+ if(*qsasconfig == NULL) {
+ *qsasconfig = (QSASConfig *) malloc((size_t) sizeof(QSASConfig));
+ if (*qsasconfig == NULL) {
fprintf(stderr, "configqsas: out of memory\n");
exit(EXIT_FAILURE);
}
@@ -890,32 +890,32 @@
offset1 = (double)MJD->base_day;
offset2 = MJD->time_sec/(double)SecInDay;
}
- qsasconfig->scale = scale;
- qsasconfig->offset1 = offset1;
- qsasconfig->offset2 = offset2;
- qsasconfig->ccontrol = ccontrol;
+ (*qsasconfig)->scale = scale;
+ (*qsasconfig)->offset1 = offset1;
+ (*qsasconfig)->offset2 = offset2;
+ (*qsasconfig)->ccontrol = ccontrol;
} else {
/* if scale is 0., then use default values. Currently, that
default is continuous time (stored as a double) is seconds since
1970-01-01 while broken-down time is Gregorian with no other
additional corrections. */
- qsasconfig->scale = 1./(double)SecInDay;
- qsasconfig->offset1 = (double) MJD_1970;
- qsasconfig->offset2 = 0.;
- qsasconfig->ccontrol = 0x0;
+ (*qsasconfig)->scale = 1./(double)SecInDay;
+ (*qsasconfig)->offset1 = (double) MJD_1970;
+ (*qsasconfig)->offset2 = 0.;
+ (*qsasconfig)->ccontrol = 0x0;
}
}
-void closeqsas(void)
+void closeqsas(QSASConfig **qsasconfig)
{
/* Close library if it has been opened. */
- if(qsasconfig != NULL) {
- free((void *) qsasconfig);
- qsasconfig = NULL;
+ if(*qsasconfig != NULL) {
+ free((void *) *qsasconfig);
+ *qsasconfig = NULL;
}
}
-int ctimeqsas(int year, int month, int day, int hour, int min, double sec, double * ctime){
+int ctimeqsas(int year, int month, int day, int hour, int min, double sec, double * ctime, QSASConfig *qsasconfig){
MJDtime MJD_value, *MJD=&MJD_value;
int forceJulian, ret;
double integral_offset1, integral_offset2, integral_scaled_ctime;
@@ -938,7 +938,7 @@
}
-void btimeqsas(int *year, int *month, int *day, int *hour, int *min, double *sec, double ctime){
+void btimeqsas(int *year, int *month, int *day, int *hour, int *min, double *sec, double ctime, QSASConfig *qsasconfig){
MJDtime MJD_value, *MJD=&MJD_value;
int forceJulian;
double integral_offset1, integral_offset2, integral_scaled_ctime;
@@ -959,7 +959,8 @@
breakDownMJD(year, month, day, hour, min, sec, MJD, forceJulian);
}
-size_t strfqsas(char * buf, size_t len, const char *format, double ctime){
+size_t strfqsas(char * buf, size_t len, const char *format, double ctime, QSASConfig *qsasconfig)
+{
MJDtime MJD_value, *MJD=&MJD_value;
int forceJulian;
double integral_offset1, integral_offset2, integral_scaled_ctime;
Modified: trunk/lib/qsastime/qsastime.h
===================================================================
--- trunk/lib/qsastime/qsastime.h 2009-02-20 19:38:15 UTC (rev 9563)
+++ trunk/lib/qsastime/qsastime.h 2009-02-20 19:43:15 UTC (rev 9564)
@@ -98,13 +98,15 @@
}QSASConfig;
-QSASTIMEDLLIMPEXP_DATA(QSASConfig) *qsasconfig;
-
/* externally accessible functions */
-QSASTIMEDLLIMPEXP void configqsas(double scale, double offset1, double offset2, int ccontrol, int ifbtime_offset, int year, int month, int day, int hour, int min, double sec);
-QSASTIMEDLLIMPEXP void closeqsas(void);
-QSASTIMEDLLIMPEXP int ctimeqsas(int year, int month, int day, int hour, int min, double sec, double * ctime);
-QSASTIMEDLLIMPEXP void btimeqsas(int *year, int *month, int *day, int *hour, int *min, double *sec, double ctime);
-QSASTIMEDLLIMPEXP size_t strfqsas(char * buf, size_t len, const char *format, double ctime);
+QSASTIMEDLLIMPEXP void configqsas(double scale, double offset1, double offset2, int ccontrol, int ifbtime_offset, int year, int month, int day, int hour, int min, double sec, QSASConfig **qsasconfig);
+QSASTIMEDLLIMPEXP void closeqsas(QSASConfig **qsasconfig);
+
+QSASTIMEDLLIMPEXP int ctimeqsas(int year, int month, int day, int hour, int min, double sec, double * ctime, QSASConfig *qsasconfig);
+
+QSASTIMEDLLIMPEXP void btimeqsas(int *year, int *month, int *day, int *hour, int *min, double *sec, double ctime, QSASConfig *qsasconfig);
+
+QSASTIMEDLLIMPEXP size_t strfqsas(char * buf, size_t len, const char *format, double ctime, QSASConfig *qsasconfig);
+
#endif
Modified: trunk/src/plbox.c
===================================================================
--- trunk/src/plbox.c 2009-02-20 19:38:15 UTC (rev 9563)
+++ trunk/src/plbox.c 2009-02-20 19:43:15 UTC (rev 9564)
@@ -1206,6 +1206,7 @@
const char *timefmt;
double tm;
double t;
+ QSASConfig *qsasconfig = NULL;
/* Set plot options from input */
@@ -1252,10 +1253,10 @@
for (tn = tp; BETW(tn, vpwxmi, vpwxma); tn += xtick1) {
if (ldx) {
t = (double) tn;
- configqsas(1./86400., 0., 0., 0x0, 1, 1970, 0, 1, 0, 0, 0.);
- ctimeqsas(1970,0,1,0,0,t,&tm);
- strfqsas(string, STRING_LEN, timefmt, tm);
- closeqsas();
+ configqsas(1./86400., 0., 0., 0x0, 1, 1970, 0, 1, 0, 0, 0., &qsasconfig);
+ ctimeqsas(1970,0,1,0,0,t,&tm, qsasconfig);
+ strfqsas(string, STRING_LEN, timefmt, tm, qsasconfig);
+ closeqsas(&qsasconfig);
}
else {
plform(tn, xscale, xprec, string, STRING_LEN, llx, lfx);
@@ -1303,10 +1304,10 @@
for (tn = tp; BETW(tn, vpwymi, vpwyma); tn += ytick1) {
if (ldy) {
t = (double) tn;
- configqsas(1./86400., 0., 0., 0x0, 1, 1970, 0, 1, 0, 0, 0.);
- ctimeqsas(1970,0,1,0,0,t,&tm);
- strfqsas(string, STRING_LEN, timefmt, tm);
- closeqsas();
+ configqsas(1./86400., 0., 0., 0x0, 1, 1970, 0, 1, 0, 0, 0., &qsasconfig);
+ ctimeqsas(1970,0,1,0,0,t,&tm, qsasconfig);
+ strfqsas(string, STRING_LEN, timefmt, tm, qsasconfig);
+ closeqsas(&qsasconfig);
}
else {
plform(tn, yscale, yprec, string, STRING_LEN, lly, lfy);
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