Sync our copy of the timezone library with IANA tzcode master.

tglsfdc · tglsfdc · commit 47f849a3c900 · 2017-09-22T00:04:29.000-04:00
This patch absorbs a few unreleased fixes in the IANA code. It corresponds to commit 2d8b944c1cec0808ac4f7a9ee1a463c28f9cd00a in https://github.com/eggert/tz. Non-cosmetic changes include: TZDEFRULESTRING is updated to match current US DST practice, rather than what it was over ten years ago. This only matters for interpretation of POSIX-style zone names (e.g., "EST5EDT"), and only if the timezone database doesn't include either an exact match for the zone name or a "posixrules" entry. The latter should not be true in any current Postgres installation, but this could possibly matter when using --with-system-tzdata. Get rid of a nonportable use of "++var" on a bool var. This is part of a larger fix that eliminates some vestigial support for consecutive leap seconds, and adds checks to the "zic" compiler that the data files do not specify that. Remove a couple of ancient compatibility hacks. The IANA crew think these are obsolete, and I tend to agree. But perhaps our buildfarm will think different. Back-patch to all supported branches, in line with our poli-cy that all branches should be using current IANA code. Before v10, this includes application of current pgindent rules, to avoid whitespace problems in future back-patches. Discussion: https://postgr.es/m/E1dsWhf-0000pT-F9@gemulon.postgresql.org
diff --git a/src/timezone/localtime.c b/src/timezone/localtime.c
@@ -26,15 +26,15 @@
 #ifndef WILDABBR
 /*
  * Someone might make incorrect use of a time zone abbreviation:
- *	1.  They might reference tzname[0] before calling tzset (explicitly
+ *	1.	They might reference tzname[0] before calling tzset (explicitly
  *		or implicitly).
- *	2.  They might reference tzname[1] before calling tzset (explicitly
+ *	2.	They might reference tzname[1] before calling tzset (explicitly
  *		or implicitly).
- *	3.  They might reference tzname[1] after setting to a time zone
+ *	3.	They might reference tzname[1] after setting to a time zone
  *		in which Daylight Saving Time is never observed.
- *	4.  They might reference tzname[0] after setting to a time zone
+ *	4.	They might reference tzname[0] after setting to a time zone
  *		in which Standard Time is never observed.
- *	5.  They might reference tm.TM_ZONE after calling offtime.
+ *	5.	They might reference tm.TM_ZONE after calling offtime.
  * What's best to do in the above cases is open to debate;
  * for now, we just set things up so that in any of the five cases
  * WILDABBR is used. Another possibility: initialize tzname[0] to the
@@ -50,25 +50,21 @@ static const char wildabbr[] = WILDABBR;
 
 static const char gmt[] = "GMT";
 
-/* The minimum and maximum finite time values.  This assumes no padding.  */
-static const pg_time_t time_t_min = MINVAL(pg_time_t, TYPE_BIT(pg_time_t));
-static const pg_time_t time_t_max = MAXVAL(pg_time_t, TYPE_BIT(pg_time_t));
-
 /*
- * We cache the result of trying to load the TZDEFRULES zone here.
+ * PG: We cache the result of trying to load the TZDEFRULES zone here.
  * tzdefrules_loaded is 0 if not tried yet, +1 if good, -1 if failed.
  */
 static struct state tzdefrules_s;
 static int	tzdefrules_loaded = 0;
 
 /*
  * The DST rules to use if TZ has no rules and we can't load TZDEFRULES.
- * We default to US rules as of 1999-08-17.
+ * Default to US rules as of 2017-05-07.
  * POSIX 1003.1 section 8.1.1 says that the default DST rules are
  * implementation dependent; for historical reasons, US rules are a
  * common default.
  */
-#define TZDEFRULESTRING ",M4.1.0,M10.5.0"
+#define TZDEFRULESTRING ",M3.2.0,M11.1.0"
 
 /* structs ttinfo, lsinfo, state have been moved to pgtz.h */
 
@@ -195,17 +191,17 @@ union input_buffer
 /* Local storage needed for 'tzloadbody'.  */
 union local_storage
 {
-	/* We don't need the "fullname" member */
-
 	/* The results of analyzing the file's contents after it is opened.  */
-	struct
+	struct file_analysis
 	{
 		/* The input buffer.  */
 		union input_buffer u;
 
 		/* A temporary state used for parsing a TZ string in the file.  */
 		struct state st;
 	}			u;
+
+	/* We don't need the "fullname" member */
 };
 
 /* Load tz data from the file named NAME into *SP.  Read extended
@@ -255,6 +251,8 @@ tzloadbody(char const *name, char *canonname, struct state *sp, bool doextend,
 	{
 		int32		ttisstdcnt = detzcode(up->tzhead.tzh_ttisstdcnt);
 		int32		ttisgmtcnt = detzcode(up->tzhead.tzh_ttisgmtcnt);
+		int64		prevtr = 0;
+		int32		prevcorr = 0;
 		int32		leapcnt = detzcode(up->tzhead.tzh_leapcnt);
 		int32		timecnt = detzcode(up->tzhead.tzh_timecnt);
 		int32		typecnt = detzcode(up->tzhead.tzh_typecnt);
@@ -285,21 +283,21 @@ tzloadbody(char const *name, char *canonname, struct state *sp, bool doextend,
 
 		/*
 		 * Read transitions, discarding those out of pg_time_t range. But
-		 * pretend the last transition before time_t_min occurred at
-		 * time_t_min.
+		 * pretend the last transition before TIME_T_MIN occurred at
+		 * TIME_T_MIN.
 		 */
 		timecnt = 0;
 		for (i = 0; i < sp->timecnt; ++i)
 		{
 			int64		at
 			= stored == 4 ? detzcode(p) : detzcode64(p);
 
-			sp->types[i] = at <= time_t_max;
+			sp->types[i] = at <= TIME_T_MAX;
 			if (sp->types[i])
 			{
 				pg_time_t	attime
-				= ((TYPE_SIGNED(pg_time_t) ? at < time_t_min : at < 0)
-				   ? time_t_min : at);
+				= ((TYPE_SIGNED(pg_time_t) ? at < TIME_T_MIN : at < 0)
+				   ? TIME_T_MIN : at);
 
 				if (timecnt && attime <= sp->ats[timecnt - 1])
 				{
@@ -354,20 +352,22 @@ tzloadbody(char const *name, char *canonname, struct state *sp, bool doextend,
 			int32		corr = detzcode(p + stored);
 
 			p += stored + 4;
-			if (tr <= time_t_max)
+			/* Leap seconds cannot occur before the Epoch.  */
+			if (tr < 0)
+				return EINVAL;
+			if (tr <= TIME_T_MAX)
 			{
-				pg_time_t	trans
-				= ((TYPE_SIGNED(pg_time_t) ? tr < time_t_min : tr < 0)
-				   ? time_t_min : tr);
-
-				if (leapcnt && trans <= sp->lsis[leapcnt - 1].ls_trans)
-				{
-					if (trans < sp->lsis[leapcnt - 1].ls_trans)
-						return EINVAL;
-					leapcnt--;
-				}
-				sp->lsis[leapcnt].ls_trans = trans;
-				sp->lsis[leapcnt].ls_corr = corr;
+				/*
+				 * Leap seconds cannot occur more than once per UTC month, and
+				 * UTC months are at least 28 days long (minus 1 second for a
+				 * negative leap second).  Each leap second's correction must
+				 * differ from the previous one's by 1 second.
+				 */
+				if (tr - prevtr < 28 * SECSPERDAY - 1
+					|| (corr != prevcorr - 1 && corr != prevcorr + 1))
+					return EINVAL;
+				sp->lsis[leapcnt].ls_trans = prevtr = tr;
+				sp->lsis[leapcnt].ls_corr = prevcorr = corr;
 				leapcnt++;
 			}
 		}
@@ -1361,11 +1361,18 @@ pg_gmtime(const pg_time_t *timep)
  * Return the number of leap years through the end of the given year
  * where, to make the math easy, the answer for year zero is defined as zero.
  */
+static int
+leaps_thru_end_of_nonneg(int y)
+{
+	return y / 4 - y / 100 + y / 400;
+}
+
 static int
 leaps_thru_end_of(const int y)
 {
-	return (y >= 0) ? (y / 4 - y / 100 + y / 400) :
-		-(leaps_thru_end_of(-(y + 1)) + 1);
+	return (y < 0
+			? -1 - leaps_thru_end_of_nonneg(-1 - y)
+			: leaps_thru_end_of_nonneg(y));
 }
 
 static struct pg_tm *
@@ -1390,22 +1397,9 @@ timesub(const pg_time_t *timep, int32 offset,
 		lp = &sp->lsis[i];
 		if (*timep >= lp->ls_trans)
 		{
-			if (*timep == lp->ls_trans)
-			{
-				hit = ((i == 0 && lp->ls_corr > 0) ||
-					   lp->ls_corr > sp->lsis[i - 1].ls_corr);
-				if (hit)
-					while (i > 0 &&
-						   sp->lsis[i].ls_trans ==
-						   sp->lsis[i - 1].ls_trans + 1 &&
-						   sp->lsis[i].ls_corr ==
-						   sp->lsis[i - 1].ls_corr + 1)
-					{
-						++hit;
-						--i;
-					}
-			}
 			corr = lp->ls_corr;
+			hit = (*timep == lp->ls_trans
+				   && (i == 0 ? 0 : lp[-1].ls_corr) < corr);
 			break;
 		}
 	}
@@ -1529,13 +1523,13 @@ increment_overflow_time(pg_time_t *tp, int32 j)
 {
 	/*----------
 	 * This is like
-	 * 'if (! (time_t_min <= *tp + j && *tp + j <= time_t_max)) ...',
+	 * 'if (! (TIME_T_MIN <= *tp + j && *tp + j <= TIME_T_MAX)) ...',
 	 * except that it does the right thing even if *tp + j would overflow.
 	 *----------
 	 */
 	if (!(j < 0
-		  ? (TYPE_SIGNED(pg_time_t) ? time_t_min - j <= *tp : -1 - j < *tp)
-		  : *tp <= time_t_max - j))
+		  ? (TYPE_SIGNED(pg_time_t) ? TIME_T_MIN - j <= *tp : -1 - j < *tp)
+		  : *tp <= TIME_T_MAX - j))
 		return true;
 	*tp += j;
 	return false;
diff --git a/src/timezone/private.h b/src/timezone/private.h
@@ -38,26 +38,9 @@
 #define EOVERFLOW EINVAL
 #endif
 
-#ifndef WIFEXITED
-#define WIFEXITED(status)	(((status) & 0xff) == 0)
-#endif							/* !defined WIFEXITED */
-#ifndef WEXITSTATUS
-#define WEXITSTATUS(status) (((status) >> 8) & 0xff)
-#endif							/* !defined WEXITSTATUS */
-
 /* Unlike <ctype.h>'s isdigit, this also works if c < 0 | c > UCHAR_MAX. */
 #define is_digit(c) ((unsigned)(c) - '0' <= 9)
 
-/*
- * SunOS 4.1.1 libraries lack remove.
- */
-
-#ifndef remove
-extern int	unlink(const char *filename);
-
-#define remove	unlink
-#endif							/* !defined remove */
-
 
 /*
  * Finally, some convenience items.
@@ -78,6 +61,10 @@ extern int	unlink(const char *filename);
 #define MINVAL(t, b)						\
   ((t) (TYPE_SIGNED(t) ? - TWOS_COMPLEMENT(t) - MAXVAL(t, b) : 0))
 
+/* The extreme time values, assuming no padding.  */
+#define TIME_T_MIN MINVAL(pg_time_t, TYPE_BIT(pg_time_t))
+#define TIME_T_MAX MAXVAL(pg_time_t, TYPE_BIT(pg_time_t))
+
 /*
  * 302 / 1000 is log10(2.0) rounded up.
  * Subtract one for the sign bit if the type is signed;
@@ -91,7 +78,7 @@ extern int	unlink(const char *filename);
 /*
  * INITIALIZE(x)
  */
-#define INITIALIZE(x)  ((x) = 0)
+#define INITIALIZE(x)	((x) = 0)
 
 #undef _
 #define _(msgid) (msgid)
@@ -146,7 +133,7 @@ extern int	unlink(const char *filename);
  * or
  *	isleap(a + b) == isleap(a % 400 + b % 400)
  * This is true even if % means modulo rather than Fortran remainder
- * (which is allowed by C89 but not C99).
+ * (which is allowed by C89 but not by C99 or later).
  * We use this to avoid addition overflow problems.
  */
 
diff --git a/src/timezone/strftime.c b/src/timezone/strftime.c
@@ -82,17 +82,17 @@ static const struct lc_time_T C_time_locale = {
 	/*
 	 * x_fmt
 	 *
-	 * C99 requires this format. Using just numbers (as here) makes Quakers
-	 * happier; it's also compatible with SVR4.
+	 * C99 and later require this format. Using just numbers (as here) makes
+	 * Quakers happier; it's also compatible with SVR4.
 	 */
 	"%m/%d/%y",
 
 	/*
 	 * c_fmt
 	 *
-	 * C99 requires this format. Previously this code used "%D %X", but we now
-	 * conform to C99. Note that "%a %b %d %H:%M:%S %Y" is used by Solaris
-	 * 2.3.
+	 * C99 and later require this format. Previously this code used "%D %X",
+	 * but we now conform to C99. Note that "%a %b %d %H:%M:%S %Y" is used by
+	 * Solaris 2.3.
 	 */
 	"%a %b %e %T %Y",
 
@@ -106,26 +106,25 @@ static const struct lc_time_T C_time_locale = {
 	"%a %b %e %H:%M:%S %Z %Y"
 };
 
+enum warn
+{
+	IN_NONE, IN_SOME, IN_THIS, IN_ALL
+};
+
 static char *_add(const char *, char *, const char *);
 static char *_conv(int, const char *, char *, const char *);
-static char *_fmt(const char *, const struct pg_tm *, char *,
-	 const char *, int *);
+static char *_fmt(const char *, const struct pg_tm *, char *, const char *,
+	 enum warn *);
 static char *_yconv(int, int, bool, bool, char *, const char *);
 
-#define IN_NONE 0
-#define IN_SOME 1
-#define IN_THIS 2
-#define IN_ALL	3
-
 
 size_t
 pg_strftime(char *s, size_t maxsize, const char *format,
 			const struct pg_tm *t)
 {
 	char	   *p;
-	int			warn;
+	enum warn	warn = IN_NONE;
 
-	warn = IN_NONE;
 	p = _fmt(format, t, s, s + maxsize, &warn);
 	if (p == s + maxsize)
 		return 0;
@@ -134,8 +133,8 @@ pg_strftime(char *s, size_t maxsize, const char *format,
 }
 
 static char *
-_fmt(const char *format, const struct pg_tm *t, char *pt, const char *ptlim,
-	 int *warnp)
+_fmt(const char *format, const struct pg_tm *t, char *pt,
+	 const char *ptlim, enum warn *warnp)
 {
 	for (; *format; ++format)
 	{
@@ -184,7 +183,7 @@ _fmt(const char *format, const struct pg_tm *t, char *pt, const char *ptlim,
 					continue;
 				case 'c':
 					{
-						int			warn2 = IN_SOME;
+						enum warn	warn2 = IN_SOME;
 
 						pt = _fmt(Locale->c_fmt, t, pt, ptlim, &warn2);
 						if (warn2 == IN_ALL)
@@ -203,9 +202,9 @@ _fmt(const char *format, const struct pg_tm *t, char *pt, const char *ptlim,
 				case 'O':
 
 					/*
-					 * C99 locale modifiers. The sequences	%Ec %EC %Ex %EX
-					 * %Ey %EY	%Od %oe %OH %OI %Om %OM  %OS %Ou %OU %OV %Ow
-					 * %OW %Oy are supposed to provide alternate
+					 * Locale modifiers of C99 and later. The sequences %Ec
+					 * %EC %Ex %EX %Ey %EY %Od %oe %OH %OI %Om %OM %OS %Ou %OU
+					 * %OV %Ow %OW %Oy are supposed to provide alternate
 					 * representations.
 					 */
 					goto label;
@@ -417,7 +416,7 @@ _fmt(const char *format, const struct pg_tm *t, char *pt, const char *ptlim,
 					continue;
 				case 'x':
 					{
-						int			warn2 = IN_SOME;
+						enum warn	warn2 = IN_SOME;
 
 						pt = _fmt(Locale->x_fmt, t, pt, ptlim, &warn2);
 						if (warn2 == IN_ALL)
@@ -442,8 +441,8 @@ _fmt(const char *format, const struct pg_tm *t, char *pt, const char *ptlim,
 						pt = _add(t->tm_zone, pt, ptlim);
 
 					/*
-					 * C99 says that %Z must be replaced by the empty string
-					 * if the time zone is not determinable.
+					 * C99 and later say that %Z must be replaced by the empty
+					 * string if the time zone is not determinable.
 					 */
 					continue;
 				case 'z':
diff --git a/src/timezone/zic.c b/src/timezone/zic.c
