/*------------------------------------------------------------------------- * * nabstime.c-- * parse almost any absolute date getdate(3) can (& some it can't) * * Copyright (c) 1994, Regents of the University of California * * * IDENTIFICATION * $Header: /usr/local/cvsroot/pgsql/src/backend/utils/adt/nabstime.c,v 1.34 1997/09/08 21:48:32 momjian Exp $ * *------------------------------------------------------------------------- */ #include #include #include #include #include "postgres.h" #include #ifdef HAVE_FLOAT_H #include #endif #ifdef HAVE_LIMITS_H #include #endif #ifndef USE_POSIX_TIME #include #endif #include "utils/builtins.h" #include "access/xact.h" static AbsoluteTime tm2abstime(struct tm * tm, int tz); #define MIN_DAYNUM -24856 /* December 13, 1901 */ #define MAX_DAYNUM 24854 /* January 18, 2038 */ /* GetCurrentAbsoluteTime() * Get the current system time. Set timezone parameters if not specified elsewhere. * Define HasTZSet to allow clients to specify the default timezone. * * Returns the number of seconds since epoch (January 1 1970 GMT) */ AbsoluteTime GetCurrentAbsoluteTime(void) { time_t now; #ifdef USE_POSIX_TIME struct tm *tm; now = time(NULL); #else /* ! USE_POSIX_TIME */ struct timeb tb; /* the old V7-ism */ ftime(&tb); now = tb.time; #endif if (!HasCTZSet) { #ifdef USE_POSIX_TIME #if defined(HAVE_TZSET) && defined(HAVE_INT_TIMEZONE) tm = localtime(&now); CDayLight = tm->tm_isdst; CTimeZone = (tm->tm_isdst ? (timezone - 3600) : timezone); strcpy(CTZName, tzname[tm->tm_isdst]); #else /* !HAVE_TZSET */ tm = localtime(&now); CTimeZone = -tm->tm_gmtoff; /* tm_gmtoff is Sun/DEC-ism */ CDayLight = (tm->tm_isdst > 0); /* * XXX is there a better way to get local timezone string w/o * tzname? - tgl 97/03/18 */ strftime(CTZName, MAXTZLEN, "%Z", tm); /* * XXX FreeBSD man pages indicate that this should work - tgl * 97/04/23 */ strcpy(CTZName, tm->tm_zone); #endif #else /* ! USE_POSIX_TIME */ CTimeZone = tb.timezone * 60; CDayLight = (tb.dstflag != 0); /* * XXX does this work to get the local timezone string in V7? - * tgl 97/03/18 */ strftime(CTZName, MAXTZLEN, "%Z", localtime(&now)); #endif }; #ifdef DATEDEBUG printf("GetCurrentAbsoluteTime- timezone is %s -> %d seconds from UTC\n", CTZName, CTimeZone); #endif return ((AbsoluteTime) now); } /* GetCurrentAbsoluteTime() */ void GetCurrentTime(struct tm * tm) { int tz; abstime2tm(GetCurrentTransactionStartTime(), &tz, tm, NULL); return; } /* GetCurrentTime() */ void abstime2tm(AbsoluteTime time, int *tzp, struct tm * tm, char *tzn) { #ifdef USE_POSIX_TIME struct tm *tx; #else /* ! USE_POSIX_TIME */ struct timeb tb; /* the old V7-ism */ ftime(&tb); #endif #ifdef USE_POSIX_TIME if (tzp != NULL) { tx = localtime((time_t *) &time); } else { tx = gmtime((time_t *) &time); }; #else #endif #ifdef DATEDEBUG #ifdef HAVE_INT_TIMEZONE printf("datetime2tm- (localtime) %d.%02d.%02d %02d:%02d:%02d %s %s dst=%d\n", tx->tm_year, tx->tm_mon, tx->tm_mday, tx->tm_hour, tx->tm_min, tx->tm_sec, tzname[0], tzname[1], tx->tm_isdst); #else printf("datetime2tm- (localtime) %d.%02d.%02d %02d:%02d:%02d %s dst=%d\n", tx->tm_year, tx->tm_mon, tx->tm_mday, tx->tm_hour, tx->tm_min, tx->tm_sec, tx->tm_zone, tx->tm_isdst); #endif #else #endif tm->tm_year = tx->tm_year + 1900; tm->tm_mon = tx->tm_mon + 1; tm->tm_mday = tx->tm_mday; tm->tm_hour = tx->tm_hour; tm->tm_min = tx->tm_min; tm->tm_sec = tx->tm_sec; tm->tm_isdst = tx->tm_isdst; #ifdef USE_POSIX_TIME #ifdef HAVE_INT_TIMEZONE if (tzp != NULL) *tzp = (tm->tm_isdst ? (timezone - 3600) : timezone); if (tzn != NULL) strcpy(tzn, tzname[tm->tm_isdst]); #else /* !HAVE_INT_TIMEZONE */ tm->tm_gmtoff = tx->tm_gmtoff; tm->tm_zone = tx->tm_zone; if (tzp != NULL) *tzp = -tm->tm_gmtoff; /* tm_gmtoff is Sun/DEC-ism */ /* XXX FreeBSD man pages indicate that this should work - tgl 97/04/23 */ if (tzn != NULL) strcpy(tzn, tm->tm_zone); #endif #else /* ! USE_POSIX_TIME */ if (tzp != NULL) *tzp = tb.timezone * 60; /* * XXX does this work to get the local timezone string in V7? - tgl * 97/03/18 */ if (tzn != NULL) strftime(tzn, MAXTZLEN, "%Z", localtime(&now)); #endif return; } /* abstime2tm() */ /* tm2abstime() * Convert a tm structure to abstime. * Note that tm has full year (not 1900-based) and 1-based month. */ static AbsoluteTime tm2abstime(struct tm * tm, int tz) { int day, sec; /* validate, before going out of range on some members */ if (tm->tm_year < 1901 || tm->tm_year > 2038 || tm->tm_mon < 1 || tm->tm_mon > 12 || tm->tm_mday < 1 || tm->tm_mday > 31 || tm->tm_hour < 0 || tm->tm_hour >= 24 || tm->tm_min < 0 || tm->tm_min > 59 || tm->tm_sec < 0 || tm->tm_sec > 59) return (INVALID_ABSTIME); day = (date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - date2j(1970, 1, 1)); /* check for time out of range */ if ((day < MIN_DAYNUM) || (day > MAX_DAYNUM)) return (INVALID_ABSTIME); /* convert to seconds */ sec = tm->tm_sec + tz + (tm->tm_min + (day * 24 + tm->tm_hour) * 60) * 60; /* check for overflow */ if ((day == MAX_DAYNUM && sec < 0) || (day == MIN_DAYNUM && sec > 0)) return (INVALID_ABSTIME); /* check for reserved values (e.g. "current" on edge of usual range */ if (!AbsoluteTimeIsReal(sec)) return (INVALID_ABSTIME); return (sec); } /* tm2abstime() */ /* nabstimein() * Decode date/time string and return abstime. */ AbsoluteTime nabstimein(char *str) { AbsoluteTime result; double fsec; int tz = 0; struct tm date, *tm = &date; char *field[MAXDATEFIELDS]; char lowstr[MAXDATELEN + 1]; int dtype; int nf, ftype[MAXDATEFIELDS]; if (!PointerIsValid(str)) elog(WARN, "Bad (null) abstime external representation", NULL); if (strlen(str) > MAXDATELEN) elog(WARN, "Bad (length) abstime external representation '%s'", str); if ((ParseDateTime(str, lowstr, field, ftype, MAXDATEFIELDS, &nf) != 0) || (DecodeDateTime(field, ftype, nf, &dtype, tm, &fsec, &tz) != 0)) elog(WARN, "Bad abstime external representation '%s'", str); #ifdef DATEDEBUG printf("nabstimein- %d fields are type %d (DTK_DATE=%d)\n", nf, dtype, DTK_DATE); #endif switch (dtype) { case DTK_DATE: result = tm2abstime(tm, tz); break; case DTK_EPOCH: result = EPOCH_ABSTIME; break; case DTK_CURRENT: result = CURRENT_ABSTIME; break; case DTK_LATE: result = NOEND_ABSTIME; break; case DTK_EARLY: result = NOSTART_ABSTIME; break; case DTK_INVALID: result = INVALID_ABSTIME; break; default: elog(WARN, "Bad abstime (internal coding error) '%s'", str); result = INVALID_ABSTIME; break; }; return result; } /* nabstimein() */ /* nabstimeout() * Given an AbsoluteTime return the English text version of the date */ char * nabstimeout(AbsoluteTime time) { char *result; int tz; double fsec = 0; struct tm tt, *tm = &tt; char buf[MAXDATELEN + 1]; char zone[MAXDATELEN + 1], *tzn = zone; switch (time) { case EPOCH_ABSTIME: strcpy(buf, EPOCH); break; case INVALID_ABSTIME: strcpy(buf, INVALID); break; case CURRENT_ABSTIME: strcpy(buf, DCURRENT); break; case NOEND_ABSTIME: strcpy(buf, LATE); break; case NOSTART_ABSTIME: strcpy(buf, EARLY); break; default: abstime2tm(time, &tz, tm, tzn); #if DATEDEBUG #endif EncodeDateTime(tm, fsec, &tz, &tzn, DateStyle, buf); break; } result = PALLOC(strlen(buf) + 1); strcpy(result, buf); return (result); } /* nabstimeout() */ /* * AbsoluteTimeIsBefore -- true iff time1 is before time2. * AbsoluteTimeIsBefore -- true iff time1 is after time2. */ bool AbsoluteTimeIsBefore(AbsoluteTime time1, AbsoluteTime time2) { Assert(AbsoluteTimeIsValid(time1)); Assert(AbsoluteTimeIsValid(time2)); if (time1 == CURRENT_ABSTIME) time1 = GetCurrentTransactionStartTime(); if (time2 == CURRENT_ABSTIME) time2 = GetCurrentTransactionStartTime(); return (time1 < time2); } bool AbsoluteTimeIsAfter(AbsoluteTime time1, AbsoluteTime time2) { Assert(AbsoluteTimeIsValid(time1)); Assert(AbsoluteTimeIsValid(time2)); if (time1 == CURRENT_ABSTIME) time1 = GetCurrentTransactionStartTime(); if (time2 == CURRENT_ABSTIME) time2 = GetCurrentTransactionStartTime(); return (time1 > time2); } /* abstime_finite() */ bool abstime_finite(AbsoluteTime abstime) { return ((abstime != INVALID_ABSTIME) && (abstime != NOSTART_ABSTIME) && (abstime != NOEND_ABSTIME)); } /* abstime_datetime() */ /* * abstimeeq - returns 1, iff arguments are equal * abstimene - returns 1, iff arguments are not equal * abstimelt - returns 1, iff t1 less than t2 * abstimegt - returns 1, iff t1 greater than t2 * abstimele - returns 1, iff t1 less than or equal to t2 * abstimege - returns 1, iff t1 greater than or equal to t2 */ bool abstimeeq(AbsoluteTime t1, AbsoluteTime t2) { if (t1 == INVALID_ABSTIME || t2 == INVALID_ABSTIME) return (FALSE); if (t1 == CURRENT_ABSTIME) t1 = GetCurrentTransactionStartTime(); if (t2 == CURRENT_ABSTIME) t2 = GetCurrentTransactionStartTime(); return (t1 == t2); } bool abstimene(AbsoluteTime t1, AbsoluteTime t2) { if (t1 == INVALID_ABSTIME || t2 == INVALID_ABSTIME) return (FALSE); if (t1 == CURRENT_ABSTIME) t1 = GetCurrentTransactionStartTime(); if (t2 == CURRENT_ABSTIME) t2 = GetCurrentTransactionStartTime(); return (t1 != t2); } bool abstimelt(AbsoluteTime t1, AbsoluteTime t2) { if (t1 == INVALID_ABSTIME || t2 == INVALID_ABSTIME) return (FALSE); if (t1 == CURRENT_ABSTIME) t1 = GetCurrentTransactionStartTime(); if (t2 == CURRENT_ABSTIME) t2 = GetCurrentTransactionStartTime(); return (t1 < t2); } bool abstimegt(AbsoluteTime t1, AbsoluteTime t2) { if (t1 == INVALID_ABSTIME || t2 == INVALID_ABSTIME) return (FALSE); if (t1 == CURRENT_ABSTIME) t1 = GetCurrentTransactionStartTime(); if (t2 == CURRENT_ABSTIME) t2 = GetCurrentTransactionStartTime(); return (t1 > t2); } bool abstimele(AbsoluteTime t1, AbsoluteTime t2) { if (t1 == INVALID_ABSTIME || t2 == INVALID_ABSTIME) return (FALSE); if (t1 == CURRENT_ABSTIME) t1 = GetCurrentTransactionStartTime(); if (t2 == CURRENT_ABSTIME) t2 = GetCurrentTransactionStartTime(); return (t1 <= t2); } bool abstimege(AbsoluteTime t1, AbsoluteTime t2) { if (t1 == INVALID_ABSTIME || t2 == INVALID_ABSTIME) return (FALSE); if (t1 == CURRENT_ABSTIME) t1 = GetCurrentTransactionStartTime(); if (t2 == CURRENT_ABSTIME) t2 = GetCurrentTransactionStartTime(); return (t1 >= t2); } /* datetime_abstime() * Convert datetime to abstime. */ AbsoluteTime datetime_abstime(DateTime *datetime) { AbsoluteTime result; double fsec; struct tm tt, *tm = &tt; if (!PointerIsValid(datetime)) { result = INVALID_ABSTIME; } else if (DATETIME_IS_INVALID(*datetime)) { result = INVALID_ABSTIME; } else if (DATETIME_IS_NOBEGIN(*datetime)) { result = NOSTART_ABSTIME; } else if (DATETIME_IS_NOEND(*datetime)) { result = NOEND_ABSTIME; } else { if (DATETIME_IS_RELATIVE(*datetime)) { datetime2tm(SetDateTime(*datetime), NULL, tm, &fsec, NULL); result = tm2abstime(tm, 0); } else if (datetime2tm(*datetime, NULL, tm, &fsec, NULL) == 0) { result = tm2abstime(tm, 0); } else { result = INVALID_ABSTIME; }; }; return (result); } /* datetime_abstime() */ /* abstime_datetime() * Convert datetime to abstime. */ DateTime * abstime_datetime(AbsoluteTime abstime) { DateTime *result; if (!PointerIsValid(result = PALLOCTYPE(DateTime))) elog(WARN, "Unable to allocate space to convert abstime to datetime", NULL); switch (abstime) { case INVALID_ABSTIME: DATETIME_INVALID(*result); break; case NOSTART_ABSTIME: DATETIME_NOBEGIN(*result); break; case NOEND_ABSTIME: DATETIME_NOEND(*result); break; case EPOCH_ABSTIME: DATETIME_EPOCH(*result); break; case CURRENT_ABSTIME: DATETIME_CURRENT(*result); break; default: *result = abstime + ((date2j(1970, 1, 1) - date2j(2000, 1, 1)) * 86400); break; }; return (result); } /* abstime_datetime() */