From d685417fbb8692d5ddee8ce60fc80e6b228c81bf Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Fri, 4 Apr 2003 04:50:44 +0000
Subject: [PATCH] Avoid repeated computation of the constants date2j(1970, 1,
1) and date2j(2000, 1, 1). Should make for some marginal speed improvement
in date/time operations.
---
src/backend/utils/adt/date.c | 22 ++++++------
src/backend/utils/adt/datetime.c | 34 +++++++++++-------
src/backend/utils/adt/nabstime.c | 54 +++++++++++++++++++----------
src/backend/utils/adt/pgstatfuncs.c | 13 +------
src/backend/utils/adt/timestamp.c | 29 +++++++---------
src/include/utils/datetime.h | 8 +++--
src/include/utils/nabstime.h | 3 +-
7 files changed, 91 insertions(+), 72 deletions(-)
diff --git a/src/backend/utils/adt/date.c b/src/backend/utils/adt/date.c
index a31cce92073..5c098a7007a 100644
--- a/src/backend/utils/adt/date.c
+++ b/src/backend/utils/adt/date.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/date.c,v 1.79 2003/02/13 17:04:19 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/date.c,v 1.80 2003/04/04 04:50:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -91,7 +91,7 @@ date_in(PG_FUNCTION_ARGS)
elog(ERROR, "Unrecognized date external representation '%s'", str);
}
- date = (date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - date2j(2000, 1, 1));
+ date = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - POSTGRES_EPOCH_JDATE;
PG_RETURN_DATEADT(date);
}
@@ -108,7 +108,7 @@ date_out(PG_FUNCTION_ARGS)
*tm = &tt;
char buf[MAXDATELEN + 1];
- j2date((date + date2j(2000, 1, 1)),
+ j2date(date + POSTGRES_EPOCH_JDATE,
&(tm->tm_year), &(tm->tm_mon), &(tm->tm_mday));
EncodeDateOnly(tm, DateStyle, buf);
@@ -256,9 +256,10 @@ date_pl_interval(PG_FUNCTION_ARGS)
if (span->month != 0)
{
- j2date((dateVal + date2j(2000, 1, 1)), &(tm->tm_year), &(tm->tm_mon), &(tm->tm_mday));
+ j2date(dateVal + POSTGRES_EPOCH_JDATE,
+ &(tm->tm_year), &(tm->tm_mon), &(tm->tm_mday));
tm->tm_mon += span->month;
- dateVal = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - date2j(2000, 1, 1);
+ dateVal = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - POSTGRES_EPOCH_JDATE;
}
if (span->time != 0)
dateVal += (span->time / 86400e0);
@@ -279,9 +280,10 @@ date_mi_interval(PG_FUNCTION_ARGS)
if (span->month != 0)
{
- j2date((dateVal + date2j(2000, 1, 1)), &(tm->tm_year), &(tm->tm_mon), &(tm->tm_mday));
+ j2date(dateVal + POSTGRES_EPOCH_JDATE,
+ &(tm->tm_year), &(tm->tm_mon), &(tm->tm_mday));
tm->tm_mon -= span->month;
- dateVal = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - date2j(2000, 1, 1);
+ dateVal = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - POSTGRES_EPOCH_JDATE;
}
if (span->time != 0)
dateVal -= (span->time / 86400e0);
@@ -346,7 +348,7 @@ date_timestamptz(PG_FUNCTION_ARGS)
struct tm tt,
*tm = &tt;
- j2date((dateVal + date2j(2000, 1, 1)),
+ j2date(dateVal + POSTGRES_EPOCH_JDATE,
&(tm->tm_year), &(tm->tm_mon), &(tm->tm_mday));
if (IS_VALID_UTIME(tm->tm_year, tm->tm_mon, tm->tm_mday))
@@ -399,7 +401,7 @@ timestamptz_date(PG_FUNCTION_ARGS)
if (timestamp2tm(timestamp, &tz, tm, &fsec, &tzn) != 0)
elog(ERROR, "Unable to convert timestamp to date");
- result = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - date2j(2000, 1, 1);
+ result = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - POSTGRES_EPOCH_JDATE;
PG_RETURN_DATEADT(result);
}
@@ -431,7 +433,7 @@ abstime_date(PG_FUNCTION_ARGS)
default:
abstime2tm(abstime, &tz, tm, NULL);
- result = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - date2j(2000, 1, 1);
+ result = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - POSTGRES_EPOCH_JDATE;
break;
}
diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index 8978cb534f7..e099245e7c9 100644
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/datetime.c,v 1.102 2003/02/22 05:57:44 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/datetime.c,v 1.103 2003/04/04 04:50:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -648,6 +648,14 @@ j2date(int jd, int *year, int *month, int *day)
return;
} /* j2date() */
+
+/*
+ * j2day - convert Julian date to day-of-week (0..6 == Sun..Sat)
+ *
+ * Note: various places use the locution j2day(date - 1) to produce a
+ * result according to the convention 0..6 = Mon..Sun. This is a bit of
+ * a crock, but will work as long as the computation here is just a modulo.
+ */
int
j2day(int date)
{
@@ -1261,7 +1269,7 @@ DecodeDateTime(char **field, int *ftype, int nf,
*dtype = DTK_DATE;
GetCurrentDateTime(tm);
j2date((date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - 1),
- &tm->tm_year, &tm->tm_mon, &tm->tm_mday);
+ &tm->tm_year, &tm->tm_mon, &tm->tm_mday);
tm->tm_hour = 0;
tm->tm_min = 0;
tm->tm_sec = 0;
@@ -1281,7 +1289,7 @@ DecodeDateTime(char **field, int *ftype, int nf,
*dtype = DTK_DATE;
GetCurrentDateTime(tm);
j2date((date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) + 1),
- &tm->tm_year, &tm->tm_mon, &tm->tm_mday);
+ &tm->tm_year, &tm->tm_mon, &tm->tm_mday);
tm->tm_hour = 0;
tm->tm_min = 0;
tm->tm_sec = 0;
@@ -1546,8 +1554,7 @@ DetermineLocalTimeZone(struct tm * tm)
delta2;
time_t mytime;
- day = (date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) -
- date2j(1970, 1, 1));
+ day = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - UNIX_EPOCH_JDATE;
mysec = tm->tm_sec + (tm->tm_min + (day * 24 + tm->tm_hour) * 60) * 60;
mytime = (time_t) mysec;
@@ -1556,8 +1563,8 @@ DetermineLocalTimeZone(struct tm * tm)
* and reassemble to get a representation of local time.
*/
tmp = localtime(&mytime);
- day = (date2j(tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday) -
- date2j(1970, 1, 1));
+ day = date2j(tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday) -
+ UNIX_EPOCH_JDATE;
locsec = tmp->tm_sec + (tmp->tm_min + (day * 24 + tmp->tm_hour) * 60) * 60;
/*
@@ -1586,8 +1593,8 @@ DetermineLocalTimeZone(struct tm * tm)
mysec += delta1;
mytime = (time_t) mysec;
tmp = localtime(&mytime);
- day = (date2j(tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday) -
- date2j(1970, 1, 1));
+ day = date2j(tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday) -
+ UNIX_EPOCH_JDATE;
locsec = tmp->tm_sec + (tmp->tm_min + (day * 24 + tmp->tm_hour) * 60) * 60;
delta2 = mysec - locsec;
if (delta2 != delta1)
@@ -1595,8 +1602,8 @@ DetermineLocalTimeZone(struct tm * tm)
mysec += (delta2 - delta1);
mytime = (time_t) mysec;
tmp = localtime(&mytime);
- day = (date2j(tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday) -
- date2j(1970, 1, 1));
+ day = date2j(tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday) -
+ UNIX_EPOCH_JDATE;
locsec = tmp->tm_sec + (tmp->tm_min + (day * 24 + tmp->tm_hour) * 60) * 60;
delta2 = mysec - locsec;
}
@@ -2360,7 +2367,7 @@ DecodeNumber(int flen, char *str, int fmask,
{
*tmask = (DTK_M(DOY) | DTK_M(MONTH) | DTK_M(DAY));
tm->tm_yday = val;
- j2date((date2j(tm->tm_year, 1, 1) + tm->tm_yday - 1),
+ j2date(date2j(tm->tm_year, 1, 1) + tm->tm_yday - 1,
&tm->tm_year, &tm->tm_mon, &tm->tm_mday);
}
@@ -3702,6 +3709,9 @@ CheckDateTokenTables(void)
{
bool ok = true;
+ Assert(UNIX_EPOCH_JDATE == date2j(1970, 1, 1));
+ Assert(POSTGRES_EPOCH_JDATE == date2j(2000, 1, 1));
+
ok &= CheckDateTokenTable("datetktbl", datetktbl, szdatetktbl);
ok &= CheckDateTokenTable("deltatktbl", deltatktbl, szdeltatktbl);
ok &= CheckDateTokenTable("australian_datetktbl",
diff --git a/src/backend/utils/adt/nabstime.c b/src/backend/utils/adt/nabstime.c
index 8a75bdffbee..ac63b2966eb 100644
--- a/src/backend/utils/adt/nabstime.c
+++ b/src/backend/utils/adt/nabstime.c
@@ -10,7 +10,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/nabstime.c,v 1.105 2003/03/20 03:34:56 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/nabstime.c,v 1.106 2003/04/04 04:50:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -85,10 +85,7 @@ static int istinterval(char *i_string,
/*
* GetCurrentAbsoluteTime()
*
- * Get the current system time. Set timezone parameters if not specified
- * elsewhere. Define HasCTZSet to allow clients to specify the default
- * timezone.
- *
+ * Get the current system time (relative to Unix epoch).
*/
AbsoluteTime
GetCurrentAbsoluteTime(void)
@@ -100,11 +97,11 @@ GetCurrentAbsoluteTime(void)
}
-/* GetCurrentAbsoluteTimeUsec()
- * Get the current system time.
+/*
+ * GetCurrentAbsoluteTimeUsec()
*
- * Returns the number of seconds since epoch (January 1 1970 GMT),
- * and returns fractional seconds (as # of microseconds) into *usec.
+ * Get the current system time (relative to Unix epoch), including fractional
+ * seconds expressed as microseconds.
*/
AbsoluteTime
GetCurrentAbsoluteTimeUsec(int *usec)
@@ -119,7 +116,31 @@ GetCurrentAbsoluteTimeUsec(int *usec)
}
-/* GetCurrentDateTime()
+/*
+ * AbsoluteTimeUsecToTimestampTz()
+ *
+ * Convert system time including microseconds to TimestampTz representation.
+ */
+TimestampTz
+AbsoluteTimeUsecToTimestampTz(AbsoluteTime sec, int usec)
+{
+ TimestampTz result;
+
+#ifdef HAVE_INT64_TIMESTAMP
+ result = ((sec - ((POSTGRES_EPOCH_JDATE - UNIX_EPOCH_JDATE) * 86400))
+ * INT64CONST(1000000)) + usec;
+#else
+ result = sec - ((POSTGRES_EPOCH_JDATE - UNIX_EPOCH_JDATE) * 86400)
+ + (usec / 1000000.0);
+#endif
+
+ return result;
+}
+
+
+/*
+ * GetCurrentDateTime()
+ *
* Get the transaction start time ("now()") broken down as a struct tm.
*/
void
@@ -131,13 +152,10 @@ GetCurrentDateTime(struct tm * tm)
}
/*
- * GetCurrentAbsoluteTimeUsec()
- *
- * Get the current system time. Set timezone parameters if not specified
- * elsewhere. Define HasCTZSet to allow clients to specify the default
- * timezone.
+ * GetCurrentTimeUsec()
*
- * Returns the number of seconds since epoch (January 1 1970 GMT)
+ * Get the transaction start time ("now()") broken down as a struct tm,
+ * including fractional seconds and timezone offset.
*/
void
GetCurrentTimeUsec(struct tm * tm, fsec_t *fsec, int *tzp)
@@ -152,7 +170,7 @@ GetCurrentTimeUsec(struct tm * tm, fsec_t *fsec, int *tzp)
#ifdef HAVE_INT64_TIMESTAMP
*fsec = usec;
#else
- *fsec = usec * 1.0e-6;
+ *fsec = usec / 1000000.0;
#endif
}
@@ -307,7 +325,7 @@ tm2abstime(struct tm * tm, int tz)
|| 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));
+ day = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - UNIX_EPOCH_JDATE;
/* check for time out of range */
if ((day < MIN_DAYNUM) || (day > MAX_DAYNUM))
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 787f0226cdc..083bb1374a4 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -328,18 +328,7 @@ pg_stat_get_backend_activity_start(PG_FUNCTION_ARGS)
if (sec == 0 && usec == 0)
PG_RETURN_NULL();
- /*
- * This method of converting "Unix time" (sec/usec since epoch) to a
- * PostgreSQL timestamp is an ugly hack -- if you fix it, be sure to
- * fix the similar hackery in timestamp.c
- */
-#ifdef HAVE_INT64_TIMESTAMP
- result = (((sec - ((date2j(2000, 1, 1) - date2j(1970, 1, 1)) * 86400))
- * INT64CONST(1000000)) + usec);
-#else
- result = (sec + (usec * 1.0e-6) - ((date2j(2000, 1, 1) -
- date2j(1970, 1, 1)) * 86400));
-#endif
+ result = AbsoluteTimeUsecToTimestampTz(sec, usec);
PG_RETURN_TIMESTAMPTZ(result);
}
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index feaec85b69e..e2f2b2d35b4 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/timestamp.c,v 1.81 2003/03/20 06:02:59 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/timestamp.c,v 1.82 2003/04/04 04:50:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -728,12 +728,7 @@ now(PG_FUNCTION_ARGS)
sec = GetCurrentTransactionStartTimeUsec(&usec);
-#ifdef HAVE_INT64_TIMESTAMP
- result = (((sec - ((date2j(2000, 1, 1) - date2j(1970, 1, 1)) * 86400))
- * INT64CONST(1000000)) + usec);
-#else
- result = (sec + (usec * 1.0e-6) - ((date2j(2000, 1, 1) - date2j(1970, 1, 1)) * 86400));
-#endif
+ result = AbsoluteTimeUsecToTimestampTz(sec, usec);
PG_RETURN_TIMESTAMPTZ(result);
}
@@ -800,7 +795,7 @@ timestamp2tm(Timestamp dt, int *tzp, struct tm * tm, fsec_t *fsec, char **tzn)
struct tm *tx;
#endif
- date0 = date2j(2000, 1, 1);
+ date0 = POSTGRES_EPOCH_JDATE;
/*
* If HasCTZSet is true then we have a brute force time zone
@@ -871,9 +866,9 @@ timestamp2tm(Timestamp dt, int *tzp, struct tm * tm, fsec_t *fsec, char **tzn)
{
#ifdef HAVE_INT64_TIMESTAMP
utime = ((dt / INT64CONST(1000000))
- + ((date0 - date2j(1970, 1, 1)) * INT64CONST(86400)));
+ + ((date0 - UNIX_EPOCH_JDATE) * INT64CONST(86400)));
#else
- utime = (dt + ((date0 - date2j(1970, 1, 1)) * 86400));
+ utime = (dt + ((date0 - UNIX_EPOCH_JDATE) * 86400));
#endif
#if defined(HAVE_TM_ZONE) || defined(HAVE_INT_TIMEZONE)
@@ -960,7 +955,7 @@ tm2timestamp(struct tm * tm, fsec_t fsec, int *tzp, Timestamp *result)
if (!IS_VALID_JULIAN(tm->tm_year, tm->tm_mon, tm->tm_mday))
return -1;
- date = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - date2j(2000, 1, 1);
+ date = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - POSTGRES_EPOCH_JDATE;
time = time2t(tm->tm_hour, tm->tm_min, tm->tm_sec, fsec);
#ifdef HAVE_INT64_TIMESTAMP
*result = ((date * INT64CONST(86400000000)) + time);
@@ -2675,7 +2670,7 @@ isoweek2date(int woy, int *year, int *mon, int *mday)
day4 = date2j(*year, 1, 4);
/* day0 == offset to first day of week (Monday) */
- day0 = (j2day(day4 - 1) % 7);
+ day0 = j2day(day4 - 1);
dayn = ((woy - 1) * 7) + (day4 - day0);
@@ -2701,7 +2696,7 @@ date2isoweek(int year, int mon, int mday)
day4 = date2j(year, 1, 4);
/* day0 == offset to first day of week (Monday) */
- day0 = (j2day(day4 - 1) % 7);
+ day0 = j2day(day4 - 1);
/*
* We need the first week containing a Thursday, otherwise this day
@@ -2709,10 +2704,10 @@ date2isoweek(int year, int mon, int mday)
*/
if (dayn < (day4 - day0))
{
- day4 = date2j((year - 1), 1, 4);
+ day4 = date2j(year - 1, 1, 4);
/* day0 == offset to first day of week (Monday) */
- day0 = (j2day(day4 - 1) % 7);
+ day0 = j2day(day4 - 1);
}
result = (((dayn - (day4 - day0)) / 7) + 1);
@@ -2723,10 +2718,10 @@ date2isoweek(int year, int mon, int mday)
*/
if (result >= 53)
{
- day4 = date2j((year + 1), 1, 4);
+ day4 = date2j(year + 1, 1, 4);
/* day0 == offset to first day of week (Monday) */
- day0 = (j2day(day4 - 1) % 7);
+ day0 = j2day(day4 - 1);
if (dayn >= (day4 - day0))
result = (((dayn - (day4 - day0)) / 7) + 1);
diff --git a/src/include/utils/datetime.h b/src/include/utils/datetime.h
index 39905ebb15e..3a419615489 100644
--- a/src/include/utils/datetime.h
+++ b/src/include/utils/datetime.h
@@ -9,7 +9,7 @@
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: datetime.h,v 1.36 2003/02/20 05:24:55 tgl Exp $
+ * $Id: datetime.h,v 1.37 2003/04/04 04:50:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -259,6 +259,10 @@ extern int day_tab[2][13];
|| (((y) == UTIME_MAXYEAR) && (((m) < UTIME_MAXMONTH) \
|| (((m) == UTIME_MAXMONTH) && ((d) <= UTIME_MAXDAY))))))
+/* Julian-date equivalents of Day 0 in Unix and Postgres reckoning */
+#define UNIX_EPOCH_JDATE 2440588 /* == date2j(1970, 1, 1) */
+#define POSTGRES_EPOCH_JDATE 2451545 /* == date2j(2000, 1, 1) */
+
extern void GetCurrentDateTime(struct tm * tm);
extern void GetCurrentTimeUsec(struct tm * tm, fsec_t *fsec, int *tzp);
@@ -289,7 +293,7 @@ extern int EncodeInterval(struct 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 bool ClearDateCache(bool, bool, bool);
+extern bool ClearDateCache(bool newval, bool doit, bool interactive);
extern int j2day(int jd);
diff --git a/src/include/utils/nabstime.h b/src/include/utils/nabstime.h
index d9391366430..0992e1abee1 100644
--- a/src/include/utils/nabstime.h
+++ b/src/include/utils/nabstime.h
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: nabstime.h,v 1.37 2002/09/01 00:58:07 tgl Exp $
+ * $Id: nabstime.h,v 1.38 2003/04/04 04:50:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -157,6 +157,7 @@ extern Datum timeofday(PG_FUNCTION_ARGS);
/* non-fmgr-callable support routines */
extern AbsoluteTime GetCurrentAbsoluteTime(void);
extern AbsoluteTime GetCurrentAbsoluteTimeUsec(int *usec);
+extern TimestampTz AbsoluteTimeUsecToTimestampTz(AbsoluteTime sec, int usec);
extern void abstime2tm(AbsoluteTime time, int *tzp, struct tm * tm, char **tzn);
#endif /* NABSTIME_H */
--
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