Use macros for time-based constants, rather than constants.

src/backend/utils/adt/date.c

@@ -2612,7 +2612,7 @@ timetz_zone(PG_FUNCTION_ARGS)
 	type = DecodeSpecial(0, lowzone, &val);
 
 	if (type == TZ || type == DTZ)
-		tz = val * 60;
+		tz = val * MINS_PER_HOUR;
 	else
 	{
 		tzp = pg_tzset(tzname);

src/backend/utils/adt/datetime.c

@@ -342,7 +342,7 @@ j2date(int jd, int *year, int *month, int *day)
 	*year = y - 4800;
 	quad = julian * 2141 / 65536;
 	*day = julian - 7834 * quad / 256;
-	*month = (quad + 10) % 12 + 1;
+	*month = (quad + 10) % MONTHS_PER_YEAR + 1;
 
 	return;
 }	/* j2date() */
@@ -952,8 +952,8 @@ DecodeDateTime(char **field, int *ftype, int nf,
 				 * DecodeTime()
 				 */
 				/* test for > 24:00:00 */
-				if (tm->tm_hour > 24 ||
-					(tm->tm_hour == 24 &&
+				if (tm->tm_hour > HOURS_PER_DAY ||
+					(tm->tm_hour == HOURS_PER_DAY &&
 					 (tm->tm_min > 0 || tm->tm_sec > 0 || *fsec > 0)))
 					return DTERR_FIELD_OVERFLOW;
 				break;
@@ -1371,12 +1371,12 @@ DecodeDateTime(char **field, int *ftype, int nf,
 		return dterr;
 
 	/* handle AM/PM */
-	if (mer != HR24 && tm->tm_hour > 12)
+	if (mer != HR24 && tm->tm_hour > HOURS_PER_DAY / 2)
 		return DTERR_FIELD_OVERFLOW;
-	if (mer == AM && tm->tm_hour == 12)
+	if (mer == AM && tm->tm_hour == HOURS_PER_DAY / 2)
 		tm->tm_hour = 0;
-	else if (mer == PM && tm->tm_hour != 12)
-		tm->tm_hour += 12;
+	else if (mer == PM && tm->tm_hour != HOURS_PER_DAY / 2)
+		tm->tm_hour += HOURS_PER_DAY / 2;
 
 	/* do additional checking for full date specs... */
 	if (*dtype == DTK_DATE)
@@ -2058,17 +2058,18 @@ DecodeTimeOnly(char **field, int *ftype, int nf,
 		return dterr;
 
 	/* handle AM/PM */
-	if (mer != HR24 && tm->tm_hour > 12)
+	if (mer != HR24 && tm->tm_hour > HOURS_PER_DAY / 2)
 		return DTERR_FIELD_OVERFLOW;
-	if (mer == AM && tm->tm_hour == 12)
+	if (mer == AM && tm->tm_hour == HOURS_PER_DAY / 2)
 		tm->tm_hour = 0;
-	else if (mer == PM && tm->tm_hour != 12)
-		tm->tm_hour += 12;
+	else if (mer == PM && tm->tm_hour != HOURS_PER_DAY / 2)
+		tm->tm_hour += HOURS_PER_DAY / 2;
 
-	if (tm->tm_hour < 0 || tm->tm_min < 0 || tm->tm_min > 59 ||
-		tm->tm_sec < 0 || tm->tm_sec > 60 || tm->tm_hour > 24 ||
+	if (tm->tm_hour < 0 || tm->tm_min < 0 || tm->tm_min > MINS_PER_HOUR - 1 ||
+		tm->tm_sec < 0 || tm->tm_sec > SECS_PER_MINUTE ||
+		tm->tm_hour > HOURS_PER_DAY ||
 	/* test for > 24:00:00 */
-		(tm->tm_hour == 24 &&
+		(tm->tm_hour == HOURS_PER_DAY &&
 		 (tm->tm_min > 0 || tm->tm_sec > 0 || *fsec > 0)) ||
 #ifdef HAVE_INT64_TIMESTAMP
 		*fsec < INT64CONST(0) || *fsec > USECS_PER_SEC
@@ -2396,13 +2397,15 @@ DecodeTime(char *str, int fmask, int range,
 
 	/* do a sanity check */
 #ifdef HAVE_INT64_TIMESTAMP
-	if (tm->tm_hour < 0 || tm->tm_min < 0 || tm->tm_min > 59 ||
-		tm->tm_sec < 0 || tm->tm_sec > 60 || *fsec < INT64CONST(0) ||
+	if (tm->tm_hour < 0 || tm->tm_min < 0 || tm->tm_min > MINS_PER_HOUR -1 ||
+		tm->tm_sec < 0 || tm->tm_sec > SECS_PER_MINUTE ||
+		*fsec < INT64CONST(0) ||
 		*fsec > USECS_PER_SEC)
 		return DTERR_FIELD_OVERFLOW;
 #else
-	if (tm->tm_hour < 0 || tm->tm_min < 0 || tm->tm_min > 59 ||
-		tm->tm_sec < 0 || tm->tm_sec > 60 || *fsec < 0 || *fsec > 1)
+	if (tm->tm_hour < 0 || tm->tm_min < 0 || tm->tm_min > MINS_PER_HOUR - 1 ||
+		tm->tm_sec < 0 || tm->tm_sec > SECS_PER_MINUTE ||
+		*fsec < 0 || *fsec > 1)
 		return DTERR_FIELD_OVERFLOW;
 #endif
 
@@ -2748,9 +2751,9 @@ DecodeTimezone(char *str, int *tzp)
 
 	if (hr < 0 || hr > 14)
 		return DTERR_TZDISP_OVERFLOW;
-	if (min < 0 || min >= 60)
+	if (min < 0 || min >= MINS_PER_HOUR)
 		return DTERR_TZDISP_OVERFLOW;
-	if (sec < 0 || sec >= 60)
+	if (sec < 0 || sec >= SECS_PER_MINUTE)
 		return DTERR_TZDISP_OVERFLOW;
 
 	tz = (hr * MINS_PER_HOUR + min) * SECS_PER_MINUTE + sec;
@@ -3324,7 +3327,7 @@ DecodeISO8601Interval(char *str,
 			{
 				case 'Y':
 					tm->tm_year += val;
-					tm->tm_mon += (fval * 12);
+					tm->tm_mon += (fval * MONTHS_PER_YEAR);
 					break;
 				case 'M':
 					tm->tm_mon += val;
@@ -3359,7 +3362,7 @@ DecodeISO8601Interval(char *str,
 						return DTERR_BAD_FORMAT;
 
 					tm->tm_year += val;
-					tm->tm_mon += (fval * 12);
+					tm->tm_mon += (fval * MONTHS_PER_YEAR);
 					if (unit == '\0')
 						return 0;
 					if (unit == 'T')
@@ -4155,7 +4158,7 @@ InstallTimeZoneAbbrevs(tzEntry *abbrevs, int n)
 	{
 		strncpy(newtbl[i].token, abbrevs[i].abbrev, TOKMAXLEN);
 		newtbl[i].type = abbrevs[i].is_dst ? DTZ : TZ;
-		TOVAL(&newtbl[i], abbrevs[i].offset / 60);
+		TOVAL(&newtbl[i], abbrevs[i].offset / MINS_PER_HOUR);
 	}
 
 	/* Check the ordering, if testing */

src/backend/utils/adt/formatting.c

@@ -2129,7 +2129,7 @@ DCH_to_char(FormatNode *node, bool is_interval, TmToChar *in, char *out, Oid col
 				 * intervals
 				 */
 				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : 2,
-						tm->tm_hour % (HOURS_PER_DAY / 2) == 0 ? 12 :
+						tm->tm_hour % (HOURS_PER_DAY / 2) == 0 ? HOURS_PER_DAY / 2 :
 						tm->tm_hour % (HOURS_PER_DAY / 2));
 				if (S_THth(n->suffix))
 					str_numth(s, s, S_TH_TYPE(n->suffix));
@@ -2486,14 +2486,14 @@ DCH_to_char(FormatNode *node, bool is_interval, TmToChar *in, char *out, Oid col
 				if (!tm->tm_mon)
 					break;
 				sprintf(s, "%*s", S_FM(n->suffix) ? 0 : -4,
-						rm_months_upper[12 - tm->tm_mon]);
+						rm_months_upper[MONTHS_PER_YEAR - tm->tm_mon]);
 				s += strlen(s);
 				break;
 			case DCH_rm:
 				if (!tm->tm_mon)
 					break;
 				sprintf(s, "%*s", S_FM(n->suffix) ? 0 : -4,
-						rm_months_lower[12 - tm->tm_mon]);
+						rm_months_lower[MONTHS_PER_YEAR - tm->tm_mon]);
 				s += strlen(s);
 				break;
 			case DCH_W:
@@ -2779,12 +2779,12 @@ DCH_from_char(FormatNode *node, char *in, TmFromChar *out)
 			case DCH_RM:
 				from_char_seq_search(&value, &s, rm_months_upper,
 									 ALL_UPPER, MAX_RM_LEN, n);
-				from_char_set_int(&out->mm, 12 - value, n);
+				from_char_set_int(&out->mm, MONTHS_PER_YEAR - value, n);
 				break;
 			case DCH_rm:
 				from_char_seq_search(&value, &s, rm_months_lower,
 									 ALL_LOWER, MAX_RM_LEN, n);
-				from_char_set_int(&out->mm, 12 - value, n);
+				from_char_set_int(&out->mm, MONTHS_PER_YEAR - value, n);
 				break;
 			case DCH_W:
 				from_char_parse_int(&out->w, &s, n);
@@ -3236,16 +3236,16 @@ do_to_timestamp(text *date_txt, text *fmt,
 
 	if (tmfc.clock == CLOCK_12_HOUR)
 	{
-		if (tm->tm_hour < 1 || tm->tm_hour > 12)
+		if (tm->tm_hour < 1 || tm->tm_hour > HOURS_PER_DAY / 2)
 			ereport(ERROR,
 					(errcode(ERRCODE_INVALID_DATETIME_FORMAT),
 					 errmsg("hour \"%d\" is invalid for the 12-hour clock",
 							tm->tm_hour),
 					 errhint("Use the 24-hour clock, or give an hour between 1 and 12.")));
 
-		if (tmfc.pm && tm->tm_hour < 12)
-			tm->tm_hour += 12;
-		else if (!tmfc.pm && tm->tm_hour == 12)
+		if (tmfc.pm && tm->tm_hour < HOURS_PER_DAY / 2)
+			tm->tm_hour += HOURS_PER_DAY / 2;
+		else if (!tmfc.pm && tm->tm_hour == HOURS_PER_DAY / 2)
 			tm->tm_hour = 0;
 	}
 
@@ -3347,7 +3347,7 @@ do_to_timestamp(text *date_txt, text *fmt,
 
 			y = ysum[isleap(tm->tm_year)];
 
-			for (i = 1; i <= 12; i++)
+			for (i = 1; i <= MONTHS_PER_YEAR; i++)
 			{
 				if (tmfc.ddd < y[i])
 					break;

src/backend/utils/adt/nabstime.c

@@ -179,13 +179,13 @@ tm2abstime(struct pg_tm * tm, int tz)
 
 	/* 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_mon < 1 || tm->tm_mon > MONTHS_PER_YEAR ||
 		tm->tm_mday < 1 || tm->tm_mday > 31 ||
 		tm->tm_hour < 0 ||
-		tm->tm_hour > 24 ||		/* test for > 24:00:00 */
-		(tm->tm_hour == 24 && (tm->tm_min > 0 || tm->tm_sec > 0)) ||
-		tm->tm_min < 0 || tm->tm_min > 59 ||
-		tm->tm_sec < 0 || tm->tm_sec > 60)
+		tm->tm_hour > HOURS_PER_DAY ||		/* test for > 24:00:00 */
+		(tm->tm_hour == HOURS_PER_DAY && (tm->tm_min > 0 || tm->tm_sec > 0)) ||
+		tm->tm_min < 0 || tm->tm_min > MINS_PER_HOUR - 1 ||
+		tm->tm_sec < 0 || tm->tm_sec > SECS_PER_MINUTE)
 		return INVALID_ABSTIME;
 
 	day = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - UNIX_EPOCH_JDATE;

src/backend/utils/adt/timestamp.c

@@ -4422,7 +4422,7 @@ timestamp_zone(PG_FUNCTION_ARGS)
 
 	if (type == TZ || type == DTZ)
 	{
-		tz = -(val * 60);
+		tz = -(val * MINS_PER_HOUR);
 		result = dt2local(timestamp, tz);
 	}
 	else
@@ -4596,7 +4596,7 @@ timestamptz_zone(PG_FUNCTION_ARGS)
 
 	if (type == TZ || type == DTZ)
 	{
-		tz = val * 60;
+		tz = val * MINS_PER_HOUR;
 		result = dt2local(timestamp, tz);
 	}
 	else

src/include/utils/timestamp.h

@@ -81,6 +81,8 @@ typedef struct
  */
 #define DAYS_PER_MONTH	30		/* assumes exactly 30 days per month */
 #define HOURS_PER_DAY	24		/* assume no daylight savings time changes */
+#define MINS_PER_HOUR	60		/* assume no daylight savings time changes */
+#define SECS_PER_MINUTE	60		/* assume no daylight savings time changes */
 
 /*
  *	This doesn't adjust for uneven daylight savings time intervals or leap