Thomas G. Lockhart 495fdfba98 Rearrange DTK_x constants.
Define constants to allow day of week decoding.
Add new datetime and timespan routines.
1997-07-01 00:25:30 +00:00

332 lines
10 KiB
C

/*-------------------------------------------------------------------------
*
* dt.h--
* Definitions for the date/time and other date/time support code.
* The support code is shared with other date data types,
* including abstime, reltime, date, and time.
*
*
* Copyright (c) 1994, Regents of the University of California
*
* $Id: dt.h,v 1.13 1997/07/01 00:25:30 thomas Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef DT_H
#define DT_H
#include <time.h>
#include <math.h>
/*
* DateTime represents absolute time.
* TimeSpan represents delta time. Keep track of months (and years)
* separately since the elapsed time spanned is unknown until instantiated
* relative to an absolute time.
*
* Note that Postgres uses "time interval" to mean a bounded interval,
* consisting of a beginning and ending time, not a time span - tgl 97/03/20
*/
typedef double DateTime;
typedef struct {
double time; /* all time units other than months and years */
int4 month; /* months and years, after time for alignment */
} TimeSpan;
/* ----------------------------------------------------------------
* time types + support macros
*
* String definitions for standard time quantities.
*
* These strings are the defaults used to form output time strings.
* Other alternate forms are hardcoded into token tables in dt.c.
* ----------------------------------------------------------------
*/
#define DAGO "ago"
#define DCURRENT "current"
#define EPOCH "epoch"
#define INVALID "invalid"
#define EARLY "-infinity"
#define LATE "infinity"
#define NOW "now"
#define TODAY "today"
#define TOMORROW "tomorrow"
#define YESTERDAY "yesterday"
#define ZULU "zulu"
#define DMICROSEC "usecond"
#define DMILLISEC "msecond"
#define DSECOND "second"
#define DMINUTE "minute"
#define DHOUR "hour"
#define DDAY "day"
#define DWEEK "week"
#define DMONTH "month"
#define DQUARTER "quarter"
#define DYEAR "year"
#define DDECADE "decade"
#define DCENTURY "century"
#define DMILLENIUM "millenium"
#define DA_D "ad"
#define DB_C "bc"
#define DTIMEZONE "timezone"
/*
* Fundamental time field definitions for parsing.
*
* Meridian: am, pm, or 24-hour style.
* Millenium: ad, bc
*/
#define AM 0
#define PM 1
#define HR24 2
#define AD 0
#define BC 1
/*
* Fields for time decoding.
* Can't have more of these than there are bits in an unsigned int
* since these are turned into bit masks during parsing and decoding.
*/
#define RESERV 0
#define MONTH 1
#define YEAR 2
#define DAY 3
#define TIME 4
#define TZ 5
#define DTZ 6
#define DTZMOD 7
#define IGNORE 8
#define AMPM 9
#define HOUR 10
#define MINUTE 11
#define SECOND 12
#define DOY 13
#define DOW 14
#define UNITS 15
#define ADBC 16
/* these are only for relative dates */
#define AGO 17
#define ABS_BEFORE 18
#define ABS_AFTER 19
/*
* Token field definitions for time parsing and decoding.
* These need to fit into the datetkn table type.
* At the moment, that means keep them within [-127,127].
* These are also used for bit masks in DecodeDateDelta()
* so actually restrict them to within [0,31] for now.
* - tgl 97/06/19
*/
#define DTK_NUMBER 0
#define DTK_STRING 1
#define DTK_DATE 2
#define DTK_TIME 3
#define DTK_TZ 4
#define DTK_AGO 5
#define DTK_SPECIAL 6
#define DTK_INVALID 7
#define DTK_CURRENT 8
#define DTK_EARLY 9
#define DTK_LATE 10
#define DTK_EPOCH 11
#define DTK_NOW 12
#define DTK_YESTERDAY 13
#define DTK_TODAY 14
#define DTK_TOMORROW 15
#define DTK_ZULU 16
#define DTK_DELTA 17
#define DTK_SECOND 18
#define DTK_MINUTE 19
#define DTK_HOUR 20
#define DTK_DAY 21
#define DTK_WEEK 22
#define DTK_MONTH 23
#define DTK_QUARTER 24
#define DTK_YEAR 25
#define DTK_DECADE 26
#define DTK_CENTURY 27
#define DTK_MILLENIUM 28
#define DTK_MILLISEC 29
#define DTK_MICROSEC 30
#define DTK_DOW 31
/*
* Bit mask definitions for time parsing.
*/
#define DTK_M(t) (0x01 << (t))
#define DTK_DATE_M (DTK_M(YEAR) | DTK_M(MONTH) | DTK_M(DAY))
#define DTK_TIME_M (DTK_M(HOUR) | DTK_M(MINUTE) | DTK_M(SECOND))
#define MAXDATELEN 47 /* maximum possible length of an input date string */
#define MAXDATEFIELDS 25 /* maximum possible number of fields in a date string */
#define TOKMAXLEN 10 /* only this many chars are stored in datetktbl */
/* keep this struct small; it gets used a lot */
typedef struct {
#if defined(aix)
char *token;
#else
char token[TOKMAXLEN];
#endif /* aix */
char type;
char value; /* this may be unsigned, alas */
} datetkn;
#ifdef NAN
#define DT_INVALID (NAN)
#else
#define DT_INVALID (DBL_MIN+DBL_MIN)
#endif
#ifdef HUGE_VAL
#define DT_NOBEGIN (-HUGE_VAL)
#define DT_NOEND (HUGE_VAL)
#else
#define DT_NOBEGIN (-DBL_MAX)
#define DT_NOEND (DBL_MAX)
#endif
#define DT_CURRENT (DBL_MIN)
#define DT_EPOCH (-DBL_MIN)
#define DATETIME_INVALID(j) {j = DT_INVALID;}
#ifdef NAN
#define DATETIME_IS_INVALID(j) (isnan(j))
#else
#define DATETIME_IS_INVALID(j) (j == DT_INVALID)
#endif
#define DATETIME_NOBEGIN(j) {j = DT_NOBEGIN;}
#define DATETIME_IS_NOBEGIN(j) (j == DT_NOBEGIN)
#define DATETIME_NOEND(j) {j = DT_NOEND;}
#define DATETIME_IS_NOEND(j) (j == DT_NOEND)
#define DATETIME_CURRENT(j) {j = DT_CURRENT;}
#define DATETIME_IS_CURRENT(j) (j == DT_CURRENT)
#define DATETIME_EPOCH(j) {j = DT_EPOCH;}
#define DATETIME_IS_EPOCH(j) (j == DT_EPOCH)
#define DATETIME_IS_RELATIVE(j) (DATETIME_IS_CURRENT(j) || DATETIME_IS_EPOCH(j))
#define DATETIME_NOT_FINITE(j) (DATETIME_IS_INVALID(j) \
|| DATETIME_IS_NOBEGIN(j) || DATETIME_IS_NOEND(j))
#define DATETIME_IS_RESERVED(j) (DATETIME_IS_RELATIVE(j) || DATETIME_NOT_FINITE(j))
#define TIMESPAN_INVALID(j) {(j).time = DT_INVALID;}
#ifdef NAN
#define TIMESPAN_IS_INVALID(j) (isnan((j).time))
#else
#define TIMESPAN_IS_INVALID(j) ((j).time == DT_INVALID)
#endif
#define TIMESPAN_NOT_FINITE(j) TIMESPAN_IS_INVALID(j)
#define TIME_PREC 1e-6
#define JROUND(j) (rint(((double) (j))/TIME_PREC)*TIME_PREC)
/*
* dt.c prototypes
*/
extern DateTime *datetime_in( char *str);
extern char *datetime_out( DateTime *dt);
extern bool datetime_eq(DateTime *dt1, DateTime *dt2);
extern bool datetime_ne(DateTime *dt1, DateTime *dt2);
extern bool datetime_lt(DateTime *dt1, DateTime *dt2);
extern bool datetime_le(DateTime *dt1, DateTime *dt2);
extern bool datetime_ge(DateTime *dt1, DateTime *dt2);
extern bool datetime_gt(DateTime *dt1, DateTime *dt2);
extern bool datetime_finite(DateTime *datetime);
extern DateTime *datetime_smaller(DateTime *dt1, DateTime *dt2);
extern DateTime *datetime_larger(DateTime *dt1, DateTime *dt2);
extern TimeSpan *timespan_in(char *str);
extern char *timespan_out(TimeSpan *span);
extern bool timespan_eq(TimeSpan *span1, TimeSpan *span2);
extern bool timespan_ne(TimeSpan *span1, TimeSpan *span2);
extern bool timespan_lt(TimeSpan *span1, TimeSpan *span2);
extern bool timespan_le(TimeSpan *span1, TimeSpan *span2);
extern bool timespan_ge(TimeSpan *span1, TimeSpan *span2);
extern bool timespan_gt(TimeSpan *span1, TimeSpan *span2);
extern bool timespan_finite(TimeSpan *span);
extern TimeSpan *timespan_smaller(TimeSpan *span1, TimeSpan *span2);
extern TimeSpan *timespan_larger(TimeSpan *span1, TimeSpan *span2);
extern text *datetime_text(DateTime *datetime);
extern DateTime *text_datetime(text *str);
extern text *timespan_text(TimeSpan *timespan);
extern TimeSpan *text_timespan(text *str);
extern DateTime *datetime_trunc(text *units, DateTime *datetime);
extern TimeSpan *timespan_trunc(text *units, TimeSpan *timespan);
extern float64 datetime_part(text *units, DateTime *datetime);
extern float64 timespan_part(text *units, TimeSpan *timespan);
extern text *datetime_zone(text *zone, DateTime *datetime);
extern TimeSpan *timespan_um(TimeSpan *span);
extern TimeSpan *timespan_add(TimeSpan *span1, TimeSpan *span2);
extern TimeSpan *timespan_sub(TimeSpan *span1, TimeSpan *span2);
extern TimeSpan *datetime_sub(DateTime *dt1, DateTime *dt2);
extern DateTime *datetime_add_span(DateTime *dt, TimeSpan *span);
extern DateTime *datetime_sub_span(DateTime *dt, TimeSpan *span);
extern TimeSpan *datetime_age(DateTime *dt1, DateTime *dt2);
extern void GetCurrentTime(struct tm *tm);
extern DateTime SetDateTime(DateTime datetime);
extern int tm2datetime(struct tm *tm, double fsec, int *tzp, DateTime *dt);
extern int datetime2tm( DateTime dt, int *tzp, struct tm *tm, double *fsec, char **tzn);
extern int timespan2tm(TimeSpan span, struct tm *tm, float8 *fsec);
extern int tm2timespan(struct tm *tm, double fsec, TimeSpan *span);
extern DateTime dt2local( DateTime dt, int timezone);
extern void j2date( int jd, int *year, int *month, int *day);
extern int date2j( int year, int month, int day);
extern int j2day( int jd);
extern double time2t(const int hour, const int min, const double sec);
extern void dt2time(DateTime dt, int *hour, int *min, double *sec);
extern int ParseDateTime( char *timestr, char *lowstr,
char *field[], int ftype[], int maxfields, int *numfields);
extern int DecodeDateTime( char *field[], int ftype[],
int nf, int *dtype, struct tm *tm, double *fsec, int *tzp);
extern int DecodeDate(char *str, int fmask, int *tmask, struct tm *tm);
extern int DecodeNumber( int flen, char *field,
int fmask, int *tmask, struct tm *tm, double *fsec);
extern int DecodeNumberField( int len, char *str,
int fmask, int *tmask, struct tm *tm, double *fsec);
extern int DecodeTime(char *str,
int fmask, int *tmask, struct tm *tm, double *fsec);
extern int DecodeTimeOnly( char *field[], int ftype[], int nf,
int *dtype, struct tm *tm, double *fsec);
extern int DecodeTimezone( char *str, int *tzp);
extern int DecodeSpecial(int field, char *lowtoken, int *val);
extern int DecodeDateDelta( char *field[], int ftype[],
int nf, int *dtype, struct tm *tm, double *fsec);
extern int DecodeUnits(int field, char *lowtoken, int *val);
extern int EncodeSpecialDateTime(DateTime dt, char *str);
extern int EncodeDateOnly(struct tm *tm, int style, char *str);
extern int EncodeTimeOnly(struct tm *tm, double fsec, int style, char *str);
extern int EncodeDateTime(struct tm *tm, double fsec, int *tzp, char **tzn, int style, char *str);
extern int EncodeTimeSpan(struct tm *tm, double fsec, int style, char *str);
extern datetkn *datebsearch(char *key, datetkn *base, unsigned int nel);
#endif /* DT_H */