From: Rasmus Lerdorf <rasmus@php.net>
Date: Sun, 28 Mar 2004 15:03:56 +0000 (+0000)
Subject: MFB test case for bug #27719 and improve comments in this tricky DST code
X-Git-Tag: php-5.0.0RC2RC1~186
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=1ece5eb5ad11613f6b637dee4901c7dd7c6abc3d;p=php

MFB test case for bug #27719 and improve comments in this tricky DST code
---

diff --git a/NEWS b/NEWS
index 399bf2e278..84c841b08f 100644
--- a/NEWS
+++ b/NEWS
@@ -1,6 +1,7 @@
 PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ????? 2004, PHP 5 Release Candidate 2
+- Fixed bug #27719 (mktime issues on and around DST changeover). (Rasmus)
 - Changed sqlite to use studlyCaps convention for its OO API. (Marcus)
 - Force destructors to have empty signatures. (Marcus)
 - Stopped file uploads from throwing E_WARNINGs and E_NOTICEs which can not be
diff --git a/ext/standard/datetime.c b/ext/standard/datetime.c
index fe973c8042..b639c37a2f 100644
--- a/ext/standard/datetime.c
+++ b/ext/standard/datetime.c
@@ -158,7 +158,7 @@ void php_mktime(INTERNAL_FUNCTION_PARAMETERS, int gm)
 			ta->tm_year = Z_LVAL_PP(arguments[5])
 			  - ((Z_LVAL_PP(arguments[5]) > 1000) ? 1900 : 0);
 		/* fall-through */
-	case 5: /* day in month (1-baesd) */
+	case 5: /* day in month (1-based) */
  		val = (*arguments[4])->value.lval; 
 		if (val < 1) { 
 			chgsecs += (1-val) * 60*60*24; 
@@ -190,10 +190,10 @@ void php_mktime(INTERNAL_FUNCTION_PARAMETERS, int gm)
 	case 1: /* hour */
 		val = (*arguments[0])->value.lval; 
 		/*
-		   We don't use 1 here to work around problems in some mktime implementations
-		   when it comes to daylight savings time.  Setting it to 4 and working back from
-		   there with the chgsecs offset makes us immune to these problems.
-		   See http://bugs.php.net/27533 for more info.
+		   We avoid midnight and a couple of hours after midnight here to work around
+		   various OS-level bugs in mktime and specifically daylight savings time issues
+		   in many mktime implementation.
+		   See bugs #27533 and #27719 for more info.
 		*/
 		if (val < 4) { 
 			chgsecs += (4-val) * 60*60; val = 4; 
@@ -215,6 +215,11 @@ void php_mktime(INTERNAL_FUNCTION_PARAMETERS, int gm)
 
 	seconds = t - chgsecs;
 
+	/*
+	   Here we check to see if the chgsecs fuzz factor we applied caused us to
+	   move from dst to non-dst or vice-versa.  If so we adjust accordingly to
+	   avoid being off by an hour on the dst changeover date.
+	*/
 	if (is_dst == -1) {
 		struct tm t1, t2;
 		t1 = *localtime(&t);
@@ -225,6 +230,11 @@ void php_mktime(INTERNAL_FUNCTION_PARAMETERS, int gm)
 			ta = localtime(&seconds);
 		}
 
+		/*
+		   If the user didn't specify whether the timestamp passed in was dst or not
+		   then we fill it in based on the dst setting at the evaluated timestamp
+		   at the current TZ
+		*/
 		is_dst = ta->tm_isdst; 
 	}
 	
diff --git a/ext/standard/tests/time/bug27719.phpt b/ext/standard/tests/time/bug27719.phpt
new file mode 100644
index 0000000000..926fc582e2
--- /dev/null
+++ b/ext/standard/tests/time/bug27719.phpt
@@ -0,0 +1,65 @@
+--TEST--
+Bug #27719: mktime returns incorrect timestamp for dst days
+--FILE--
+<?php
+	putenv("TZ=EST");  // No DST
+	$a = mktime(0, 0, 0, 4, 4, 2004, 0);
+	$b = mktime(0, 0, 0, 4, 4, 2004, 1);
+	$c = mktime(0, 0, 0, 4, 4, 2004, -1);
+	echo "$a ".date("m/d/y h:i:s\n",$a);
+	echo "$b ".date("m/d/y h:i:s\n",$b);
+	echo "$c ".date("m/d/y h:i:s\n",$c);
+	echo "\n";
+	putenv("TZ=EST5DST");  // DST not in effect
+	$a = mktime(0, 0, 0, 2, 4, 2004, 0);
+	$b = mktime(0, 0, 0, 2, 4, 2004, 1);
+	$c = mktime(0, 0, 0, 2, 4, 2004, -1);
+	echo "$a ".date("m/d/y h:i:s\n",$a);
+	echo "$b ".date("m/d/y h:i:s\n",$b);
+	echo "$c ".date("m/d/y h:i:s\n",$c);
+	echo "\n";
+	putenv("TZ=EST5DST");  // Just before DST changeover
+	$a = mktime(0, 0, 0, 4, 4, 2004, 0);
+	$b = mktime(0, 0, 0, 4, 4, 2004, 1);
+	$c = mktime(0, 0, 0, 4, 4, 2004, -1);
+	echo "$a ".date("m/d/y h:i:s\n",$a);
+	echo "$b ".date("m/d/y h:i:s\n",$b);
+	echo "$c ".date("m/d/y h:i:s\n",$c);
+	echo "\n";
+	putenv("TZ=EST5DST");  // Just after DST changeover
+	$a = mktime(3, 0, 0, 4, 4, 2004, 0);
+	$b = mktime(3, 0, 0, 4, 4, 2004, 1);
+	$c = mktime(3, 0, 0, 4, 4, 2004, -1);
+	echo "$a ".date("m/d/y h:i:s\n",$a);
+	echo "$b ".date("m/d/y h:i:s\n",$b);
+	echo "$c ".date("m/d/y h:i:s\n",$c);
+	echo "\n";
+	putenv("TZ=EST5DST");  // DST in effect
+	$a = mktime(0, 0, 0, 6, 4, 2004, 0);
+	$b = mktime(0, 0, 0, 6, 4, 2004, 1);
+	$c = mktime(0, 0, 0, 6, 4, 2004, -1);
+	echo "$a ".date("m/d/y h:i:s\n",$a);
+	echo "$b ".date("m/d/y h:i:s\n",$b);
+	echo "$c ".date("m/d/y h:i:s\n",$c);
+	echo "\n";
+?>
+--EXPECT--
+1081054800 04/04/04 12:00:00
+1081054800 04/04/04 12:00:00
+1081054800 04/04/04 12:00:00
+ 
+1075870800 02/04/04 12:00:00
+1075867200 02/03/04 11:00:00
+1075870800 02/04/04 12:00:00
+ 
+1081054800 04/04/04 12:00:00
+1081051200 04/03/04 11:00:00
+1081054800 04/04/04 12:00:00
+ 
+1081065600 04/04/04 04:00:00
+1081062000 04/04/04 03:00:00
+1081062000 04/04/04 03:00:00
+ 
+1086325200 06/04/04 01:00:00
+1086321600 06/04/04 12:00:00
+1086321600 06/04/04 12:00:00