diff options
Diffstat (limited to 'generic/tclGetDate.y')
| -rw-r--r-- | generic/tclGetDate.y | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/generic/tclGetDate.y b/generic/tclGetDate.y index 3625041..0f1d515 100644 --- a/generic/tclGetDate.y +++ b/generic/tclGetDate.y @@ -11,7 +11,7 @@ * See the file "license.terms" for information on usage and redistribution * of this file, and for a DISCLAIMER OF ALL WARRANTIES. * - * RCS: @(#) $Id: tclGetDate.y,v 1.8 2000/01/11 02:59:48 ericm Exp $ + * RCS: @(#) $Id: tclGetDate.y,v 1.9 2000/01/12 01:16:08 ericm Exp $ */ %{ @@ -603,7 +603,22 @@ ToSeconds(Hours, Minutes, Seconds, Meridian) return -1; /* Should never be reached */ } - +/* + *----------------------------------------------------------------------------- + * + * Convert -- + * + * Convert a {month, day, year, hours, minutes, seconds, meridian, dst} + * tuple into a clock seconds value. + * + * Results: + * 0 or -1 indicating success or failure. + * + * Side effects: + * Fills TimePtr with the computed value. + * + *----------------------------------------------------------------------------- + */ static int Convert(Month, Day, Year, Hours, Minutes, Seconds, Meridian, DSTmode, TimePtr) time_t Month; @@ -623,13 +638,23 @@ Convert(Month, Day, Year, Hours, Minutes, Seconds, Meridian, DSTmode, TimePtr) time_t Julian; int i; + /* Figure out how many days are in February for the given year. + * Every year divisible by 4 is a leap year. + * But, every year divisible by 100 is not a leap year. + * But, every year divisible by 400 is a leap year after all. + */ DaysInMonth[1] = (Year % 4 == 0) && (Year % 100 != 0 || Year % 400 == 0) ? 29 : 28; + + /* Check the inputs for validity */ if (Month < 1 || Month > 12 || Year < START_OF_TIME || Year > END_OF_TIME || Day < 1 || Day > DaysInMonth[(int)--Month]) return -1; + /* Start computing the value. First determine the number of days + * represented by the date, then multiply by the number of seconds/day. + */ for (Julian = Day - 1, i = 0; i < Month; i++) Julian += DaysInMonth[i]; if (Year >= EPOCH) { @@ -642,10 +667,16 @@ Convert(Month, Day, Year, Hours, Minutes, Seconds, Meridian, DSTmode, TimePtr) (((i % 100) != 0) || ((i % 400) == 0))); } Julian *= SECSPERDAY; + + /* Add the timezone offset ?? */ Julian += yyTimezone * 60L; + + /* Add the number of seconds represented by the time component */ if ((tod = ToSeconds(Hours, Minutes, Seconds, Meridian)) < 0) return -1; Julian += tod; + + /* Perform a preliminary DST compensation ?? */ if (DSTmode == DSTon || (DSTmode == DSTmaybe && TclpGetDate((TclpTime_t)&Julian, 0)->tm_isdst)) Julian -= 60 * 60; |