Repair array subscript overrun identified by Yichen Xie. Reduce the

value of MAX_TIME_PRECISION in floating-point-timestamp-storage case
from 13 to 10, which is as much as time_out is actually willing to print.
(The alternative of increasing the number of digits we are willing to
print looks risky; we might find ourselves printing roundoff garbage.)

doc/src/sgml/datatype.sgml

 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.111 2003/01/15 18:01:04 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.112 2003/01/29 01:08:42 tgl Exp $
 -->
 
  <chapter id="datatype">
@@ -1297,8 +1297,7 @@ SELECT b, char_length(b) FROM test2;
     fractional digits retained in the seconds field. By default, there
     is no explicit bound on precision.  The allowed range of
     <replaceable>p</replaceable> is from 0 to 6 for the
-    <type>timestamp</type> and <type>interval</type> types, 0 to 13
-    for the <type>time</type> types.
+    <type>timestamp</type> and <type>interval</type> types.
    </para>
 
    <note>
@@ -1314,6 +1313,12 @@ SELECT b, char_length(b) FROM test2;
    </para>
    </note>
 
+   <para>
+    For the <type>time</type> types, the allowed range of
+    <replaceable>p</replaceable> is from 0 to 6 when eight-byte integer
+    storage is used, or from 0 to 10 when floating-point storage is used.
+   </para>
+
    <para>
     Time zones, and time-zone conventions, are influenced by
     political decisions, not just earth geometry. Time zones around the
@@ -1485,7 +1490,7 @@ SELECT b, char_length(b) FROM test2;
      <para>
       The <type>time</type> type can be specified as <type>time</type> or
       as <type>time without time zone</type>. The optional precision
-      <replaceable>p</replaceable> should be between 0 and 13, and
+      <replaceable>p</replaceable> should be between 0 and 6, and
       defaults to the precision of the input time literal.
      </para>
 

src/backend/utils/adt/date.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/date.c,v 1.76 2003/01/22 20:44:20 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/date.c,v 1.77 2003/01/29 01:08:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -619,7 +619,7 @@ static void
 AdjustTimeForTypmod(TimeADT *time, int32 typmod)
 {
 #ifdef HAVE_INT64_TIMESTAMP
-	static const int64 TimeScales[MAX_TIMESTAMP_PRECISION + 1] = {
+	static const int64 TimeScales[MAX_TIME_PRECISION + 1] = {
 		INT64CONST(1000000),
 		INT64CONST(100000),
 		INT64CONST(10000),
@@ -629,7 +629,7 @@ AdjustTimeForTypmod(TimeADT *time, int32 typmod)
 		INT64CONST(1)
 	};
 
-	static const int64 TimeOffsets[MAX_TIMESTAMP_PRECISION + 1] = {
+	static const int64 TimeOffsets[MAX_TIME_PRECISION + 1] = {
 		INT64CONST(500000),
 		INT64CONST(50000),
 		INT64CONST(5000),
@@ -640,14 +640,19 @@ AdjustTimeForTypmod(TimeADT *time, int32 typmod)
 	};
 
 #else
-	static const double TimeScales[MAX_TIMESTAMP_PRECISION + 1] = {
+	/* note MAX_TIME_PRECISION differs in this case */
+	static const double TimeScales[MAX_TIME_PRECISION + 1] = {
 		1,
 		10,
 		100,
 		1000,
 		10000,
 		100000,
-		1000000
+		1000000,
+		10000000,
+		100000000,
+		1000000000,
+		10000000000
 	};
 #endif
 

src/backend/utils/adt/datetime.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/datetime.c,v 1.98 2003/01/16 00:26:45 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/datetime.c,v 1.99 2003/01/29 01:08:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -667,14 +667,13 @@ TrimTrailingZeros(char *str)
 	}
 #endif
 
-	/* chop off trailing zeros... */
+	/* chop off trailing zeros... but leave at least 2 fractional digits */
 	while ((*(str + len - 1) == '0')
 		   && (*(str + len - 3) != '.'))
 	{
 		len--;
 		*(str + len) = '\0';
 	}
-	return;
 }
 
 
@@ -3145,33 +3144,22 @@ EncodeDateOnly(struct tm * tm, int style, char *str)
 int
 EncodeTimeOnly(struct tm * tm, fsec_t fsec, int *tzp, int style, char *str)
 {
-#ifndef HAVE_INT64_TIMESTAMP
-	fsec_t		sec;
-#endif
-
 	if ((tm->tm_hour < 0) || (tm->tm_hour > 24))
 		return -1;
 
-#ifndef HAVE_INT64_TIMESTAMP
-	sec = (tm->tm_sec + fsec);
-#endif
-
 	sprintf(str, "%02d:%02d", tm->tm_hour, tm->tm_min);
 
 	/*
-	 * If we have fractional seconds, then include a decimal point We will
-	 * do up to 6 fractional digits, and we have rounded any inputs to
-	 * eliminate anything to the right of 6 digits anyway. If there are no
-	 * fractional seconds, then do not bother printing a decimal point at
-	 * all. - thomas 2001-09-29
+	 * Print fractional seconds if any.  The field widths here should be
+	 * at least equal to the larger of MAX_TIME_PRECISION and
+	 * MAX_TIMESTAMP_PRECISION.
 	 */
 	if (fsec != 0)
 	{
 #ifdef HAVE_INT64_TIMESTAMP
-		sprintf((str + strlen(str)), ":%02d", tm->tm_sec);
-		sprintf((str + strlen(str)), ".%06d", fsec);
+		sprintf((str + strlen(str)), ":%02d.%06d", tm->tm_sec, fsec);
 #else
-		sprintf((str + strlen(str)), ":%013.10f", sec);
+		sprintf((str + strlen(str)), ":%013.10f", tm->tm_sec + fsec);
 #endif
 		/* chop off trailing pairs of zeros... */
 		while ((strcmp((str + strlen(str) - 2), "00") == 0)
@@ -3179,11 +3167,7 @@ EncodeTimeOnly(struct tm * tm, fsec_t fsec, int *tzp, int style, char *str)
 			*(str + strlen(str) - 2) = '\0';
 	}
 	else
-#ifdef HAVE_INT64_TIMESTAMP
 		sprintf((str + strlen(str)), ":%02d", tm->tm_sec);
-#else
-		sprintf((str + strlen(str)), ":%02.0f", sec);
-#endif
 
 	if (tzp != NULL)
 	{
@@ -3217,20 +3201,12 @@ EncodeDateTime(struct tm * tm, fsec_t fsec, int *tzp, char **tzn, int style, cha
 				hour,
 				min;
 
-#ifndef HAVE_INT64_TIMESTAMP
-	fsec_t		sec;
-#endif
-
 	/*
 	 * Why are we checking only the month field? Change this to an
 	 * assert... if ((tm->tm_mon < 1) || (tm->tm_mon > 12)) return -1;
 	 */
 	Assert((tm->tm_mon >= 1) && (tm->tm_mon <= 12));
 
-#ifndef HAVE_INT64_TIMESTAMP
-	sec = (tm->tm_sec + fsec);
-#endif
-
 	switch (style)
 	{
 		case USE_ISO_DATES:
@@ -3241,21 +3217,20 @@ EncodeDateTime(struct tm * tm, fsec_t fsec, int *tzp, char **tzn, int style, cha
 					tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min);
 
 			/*
-			 * If we have fractional seconds, then include a decimal point
-			 * We will do up to 6 fractional digits, and we have rounded
-			 * any inputs to eliminate anything to the right of 6 digits
-			 * anyway. If there are no fractional seconds, then do not
-			 * bother printing a decimal point at all. - thomas 2001-09-29
+			 * Print fractional seconds if any.  The field widths here should
+			 * be at least equal to MAX_TIMESTAMP_PRECISION.
+			 *
+			 * In float mode, don't print fractional seconds before 1 AD,
+			 * since it's unlikely there's any precision left ...
 			 */
 #ifdef HAVE_INT64_TIMESTAMP
 			if (fsec != 0)
 			{
-				sprintf((str + strlen(str)), ":%02d", tm->tm_sec);
-				sprintf((str + strlen(str)), ".%06d", fsec);
+				sprintf((str + strlen(str)), ":%02d.%06d", tm->tm_sec, fsec);
 #else
 			if ((fsec != 0) && (tm->tm_year > 0))
 			{
-				sprintf((str + strlen(str)), ":%013.10f", sec);
+				sprintf((str + strlen(str)), ":%09.6f", tm->tm_sec + fsec);
 #endif
 				TrimTrailingZeros(str);
 			}
@@ -3292,21 +3267,20 @@ EncodeDateTime(struct tm * tm, fsec_t fsec, int *tzp, char **tzn, int style, cha
 					tm->tm_hour, tm->tm_min);
 
 			/*
-			 * If we have fractional seconds, then include a decimal point
-			 * We will do up to 6 fractional digits, and we have rounded
-			 * any inputs to eliminate anything to the right of 6 digits
-			 * anyway. If there are no fractional seconds, then do not
-			 * bother printing a decimal point at all. - thomas 2001-09-29
+			 * Print fractional seconds if any.  The field widths here should
+			 * be at least equal to MAX_TIMESTAMP_PRECISION.
+			 *
+			 * In float mode, don't print fractional seconds before 1 AD,
+			 * since it's unlikely there's any precision left ...
 			 */
 #ifdef HAVE_INT64_TIMESTAMP
 			if (fsec != 0)
 			{
-				sprintf((str + strlen(str)), ":%02d", tm->tm_sec);
-				sprintf((str + strlen(str)), ".%06d", fsec);
+				sprintf((str + strlen(str)), ":%02d.%06d", tm->tm_sec, fsec);
 #else
 			if ((fsec != 0) && (tm->tm_year > 0))
 			{
-				sprintf((str + strlen(str)), ":%013.10f", sec);
+				sprintf((str + strlen(str)), ":%09.6f", tm->tm_sec + fsec);
 #endif
 				TrimTrailingZeros(str);
 			}
@@ -3339,21 +3313,20 @@ EncodeDateTime(struct tm * tm, fsec_t fsec, int *tzp, char **tzn, int style, cha
 					tm->tm_hour, tm->tm_min);
 
 			/*
-			 * If we have fractional seconds, then include a decimal point
-			 * We will do up to 6 fractional digits, and we have rounded
-			 * any inputs to eliminate anything to the right of 6 digits
-			 * anyway. If there are no fractional seconds, then do not
-			 * bother printing a decimal point at all. - thomas 2001-09-29
+			 * Print fractional seconds if any.  The field widths here should
+			 * be at least equal to MAX_TIMESTAMP_PRECISION.
+			 *
+			 * In float mode, don't print fractional seconds before 1 AD,
+			 * since it's unlikely there's any precision left ...
 			 */
 #ifdef HAVE_INT64_TIMESTAMP
 			if (fsec != 0)
 			{
-				sprintf((str + strlen(str)), ":%02d", tm->tm_sec);
-				sprintf((str + strlen(str)), ".%06d", fsec);
+				sprintf((str + strlen(str)), ":%02d.%06d", tm->tm_sec, fsec);
 #else
 			if ((fsec != 0) && (tm->tm_year > 0))
 			{
-				sprintf((str + strlen(str)), ":%013.10f", sec);
+				sprintf((str + strlen(str)), ":%09.6f", tm->tm_sec + fsec);
 #endif
 				TrimTrailingZeros(str);
 			}
@@ -3394,21 +3367,20 @@ EncodeDateTime(struct tm * tm, fsec_t fsec, int *tzp, char **tzn, int style, cha
 			sprintf((str + 10), " %02d:%02d", tm->tm_hour, tm->tm_min);
 
 			/*
-			 * If we have fractional seconds, then include a decimal point
-			 * We will do up to 6 fractional digits, and we have rounded
-			 * any inputs to eliminate anything to the right of 6 digits
-			 * anyway. If there are no fractional seconds, then do not
-			 * bother printing a decimal point at all. - thomas 2001-09-29
+			 * Print fractional seconds if any.  The field widths here should
+			 * be at least equal to MAX_TIMESTAMP_PRECISION.
+			 *
+			 * In float mode, don't print fractional seconds before 1 AD,
+			 * since it's unlikely there's any precision left ...
 			 */
 #ifdef HAVE_INT64_TIMESTAMP
 			if (fsec != 0)
 			{
-				sprintf((str + strlen(str)), ":%02d", tm->tm_sec);
-				sprintf((str + strlen(str)), ".%06d", fsec);
+				sprintf((str + strlen(str)), ":%02d.%06d", tm->tm_sec, fsec);
 #else
 			if ((fsec != 0) && (tm->tm_year > 0))
 			{
-				sprintf((str + strlen(str)), ":%013.10f", sec);
+				sprintf((str + strlen(str)), ":%09.6f", tm->tm_sec + fsec);
 #endif
 				TrimTrailingZeros(str);
 			}

src/include/utils/date.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: date.h,v 1.21 2002/09/04 20:31:45 momjian Exp $
+ * $Id: date.h,v 1.22 2003/01/29 01:08:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -41,7 +41,7 @@ typedef struct
 #ifdef HAVE_INT64_TIMESTAMP
 #define MAX_TIME_PRECISION 6
 #else
-#define MAX_TIME_PRECISION 13
+#define MAX_TIME_PRECISION 10
 #endif
 
 /*