postgresql/src/include/utils/datetime.h
Peter Eisentraut ad4fb0d0d2 Improve EncodeDateTime and EncodeTimeOnly APIs
Use an explicit argument to tell whether to include the time zone in
the output, rather than using some undocumented pointer magic.
2012-03-14 23:03:34 +02:00

314 lines
8.6 KiB
C

/*-------------------------------------------------------------------------
*
* datetime.h
* Definitions for date/time support code.
* The support code is shared with other date data types,
* including abstime, reltime, date, and time.
*
*
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/utils/datetime.h
*
*-------------------------------------------------------------------------
*/
#ifndef DATETIME_H
#define DATETIME_H
#include "nodes/nodes.h"
#include "utils/timestamp.h"
/* this struct is declared in utils/tzparser.h: */
struct tzEntry;
/* ----------------------------------------------------------------
* time types + support macros
*
* String definitions for standard time quantities.
*
* These strings are the defaults used to form output time strings.
* Other alternative forms are hardcoded into token tables in datetime.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 DMILLENNIUM "millennium"
#define DA_D "ad"
#define DB_C "bc"
#define DTIMEZONE "timezone"
/*
* Fundamental time field definitions for parsing.
*
* Meridian: am, pm, or 24-hour style.
* Millennium: 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.
*
* Furthermore, the values for YEAR, MONTH, DAY, HOUR, MINUTE, SECOND
* must be in the range 0..14 so that the associated bitmasks can fit
* into the left half of an INTERVAL's typmod value. Since those bits
* are stored in typmods, you can't change them without initdb!
*/
#define RESERV 0
#define MONTH 1
#define YEAR 2
#define DAY 3
#define JULIAN 4
#define TZ 5
#define DTZ 6
#define DTZMOD 7
#define IGNORE_DTF 8
#define AMPM 9
#define HOUR 10
#define MINUTE 11
#define SECOND 12
#define MILLISECOND 13
#define MICROSECOND 14
#define DOY 15
#define DOW 16
#define UNITS 17
#define ADBC 18
/* these are only for relative dates */
#define AGO 19
#define ABS_BEFORE 20
#define ABS_AFTER 21
/* generic fields to help with parsing */
#define ISODATE 22
#define ISOTIME 23
/* these are only for parsing intervals */
#define WEEK 24
#define DECADE 25
#define CENTURY 26
#define MILLENNIUM 27
/* reserved for unrecognized string values */
#define UNKNOWN_FIELD 31
/*
* 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.
* - thomas 97/06/19
* Not all of these fields are used for masks in DecodeDateDelta
* so allow some larger than 31. - thomas 1997-11-17
*/
#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_MILLENNIUM 28
#define DTK_MILLISEC 29
#define DTK_MICROSEC 30
#define DTK_JULIAN 31
#define DTK_DOW 32
#define DTK_DOY 33
#define DTK_TZ_HOUR 34
#define DTK_TZ_MINUTE 35
#define DTK_ISOYEAR 36
#define DTK_ISODOW 37
/*
* Bit mask definitions for time parsing.
*/
#define DTK_M(t) (0x01 << (t))
/* Convenience: a second, plus any fractional component */
#define DTK_ALL_SECS_M (DTK_M(SECOND) | DTK_M(MILLISECOND) | DTK_M(MICROSECOND))
#define DTK_DATE_M (DTK_M(YEAR) | DTK_M(MONTH) | DTK_M(DAY))
#define DTK_TIME_M (DTK_M(HOUR) | DTK_M(MINUTE) | DTK_ALL_SECS_M)
#define MAXDATELEN 63 /* maximum possible length of an input date
* string (not counting tr. null) */
#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
{
char token[TOKMAXLEN];
char type;
char value; /* this may be unsigned, alas */
} datetkn;
/* one of its uses is in tables of time zone abbreviations */
typedef struct TimeZoneAbbrevTable
{
int numabbrevs;
datetkn abbrevs[1]; /* VARIABLE LENGTH ARRAY */
} TimeZoneAbbrevTable;
/* FMODULO()
* Macro to replace modf(), which is broken on some platforms.
* t = input and remainder
* q = integer part
* u = divisor
*/
#define FMODULO(t,q,u) \
do { \
(q) = (((t) < 0) ? ceil((t) / (u)) : floor((t) / (u))); \
if ((q) != 0) (t) -= rint((q) * (u)); \
} while(0)
/* TMODULO()
* Like FMODULO(), but work on the timestamp datatype (either int64 or float8).
* We assume that int64 follows the C99 semantics for division (negative
* quotients truncate towards zero).
*/
#ifdef HAVE_INT64_TIMESTAMP
#define TMODULO(t,q,u) \
do { \
(q) = ((t) / (u)); \
if ((q) != 0) (t) -= ((q) * (u)); \
} while(0)
#else
#define TMODULO(t,q,u) \
do { \
(q) = (((t) < 0) ? ceil((t) / (u)) : floor((t) / (u))); \
if ((q) != 0) (t) -= rint((q) * (u)); \
} while(0)
#endif
/*
* Date/time validation
* Include check for leap year.
*/
extern const int day_tab[2][13];
#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
/*
* Datetime input parsing routines (ParseDateTime, DecodeDateTime, etc)
* return zero or a positive value on success. On failure, they return
* one of these negative code values. DateTimeParseError may be used to
* produce a correct ereport.
*/
#define DTERR_BAD_FORMAT (-1)
#define DTERR_FIELD_OVERFLOW (-2)
#define DTERR_MD_FIELD_OVERFLOW (-3) /* triggers hint about DateStyle */
#define DTERR_INTERVAL_OVERFLOW (-4)
#define DTERR_TZDISP_OVERFLOW (-5)
extern void GetCurrentDateTime(struct pg_tm * tm);
extern void GetCurrentTimeUsec(struct pg_tm * tm, fsec_t *fsec, int *tzp);
extern void j2date(int jd, int *year, int *month, int *day);
extern int date2j(int year, int month, int day);
extern int ParseDateTime(const char *timestr, char *workbuf, size_t buflen,
char **field, int *ftype,
int maxfields, int *numfields);
extern int DecodeDateTime(char **field, int *ftype,
int nf, int *dtype,
struct pg_tm * tm, fsec_t *fsec, int *tzp);
extern int DecodeTimeOnly(char **field, int *ftype,
int nf, int *dtype,
struct pg_tm * tm, fsec_t *fsec, int *tzp);
extern int DecodeInterval(char **field, int *ftype, int nf, int range,
int *dtype, struct pg_tm * tm, fsec_t *fsec);
extern int DecodeISO8601Interval(char *str,
int *dtype, struct pg_tm * tm, fsec_t *fsec);
extern void DateTimeParseError(int dterr, const char *str,
const char *datatype);
extern int DetermineTimeZoneOffset(struct pg_tm * tm, pg_tz *tzp);
extern void EncodeDateOnly(struct pg_tm * tm, int style, char *str);
extern void EncodeTimeOnly(struct pg_tm * tm, fsec_t fsec, bool print_tz, int tz, int style, char *str);
extern void EncodeDateTime(struct pg_tm * tm, fsec_t fsec, bool print_tz, int tz, const char *tzn, int style, char *str);
extern void EncodeInterval(struct pg_tm * tm, fsec_t fsec, int style, char *str);
extern int DecodeSpecial(int field, char *lowtoken, int *val);
extern int DecodeUnits(int field, char *lowtoken, int *val);
extern int j2day(int jd);
extern Node *TemporalTransform(int32 max_precis, Node *node);
extern bool CheckDateTokenTables(void);
extern void ConvertTimeZoneAbbrevs(TimeZoneAbbrevTable *tbl,
struct tzEntry *abbrevs, int n);
extern void InstallTimeZoneAbbrevs(TimeZoneAbbrevTable *tbl);
extern Datum pg_timezone_abbrevs(PG_FUNCTION_ARGS);
extern Datum pg_timezone_names(PG_FUNCTION_ARGS);
#endif /* DATETIME_H */