[REVIEW 3-5][PATCH] Fix leap year calculation

Hi there,

The attached patch fixes a bug in our current leap year calculation
code.  It is based on the algorithm posted on wikipedia[1], and seems to
correctly identify year 2000 as a leap year.

Without this, Calc would convert 2000-2-29 into 1899-12-30 on load,
which is ugly but very hard to detect.

Please consider this for 3.5.1, in which case I'll need 3 sign-offs.  I
haven't pushed this to master yet.  I wanted to run it by Eike first
before pushing to master.

Kohei

[1] http://en.wikipedia.org/wiki/Leap_year

-- 
Kohei Yoshida, LibreOffice hacker, Calc

From 0666b5dca1a210ce7abc61a522a59c48661fe664 Mon Sep 17 00:00:00 2001
From: Kohei Yoshida <kohei.yoshida@suse.com>
Date: Tue, 28 Feb 2012 22:01:52 -0500
Subject: [PATCH] Correctly calculate leap year.

With the old code, year 2000 would not be a leap year, but it actually
is.  With this, Calc correctly loads cell with date value of 2000-2-29.
---
 sax/source/tools/converter.cxx |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/sax/source/tools/converter.cxx b/sax/source/tools/converter.cxx
index eb8cc74..95f6494 100644
--- a/sax/source/tools/converter.cxx
+++ b/sax/source/tools/converter.cxx
@@ -1304,7 +1304,7 @@ readDateTimeComponent(const ::rtl::OUString & rString,
 static bool lcl_isLeapYear(const sal_uInt32 nYear)
 {
     return ((nYear % 4) == 0)
-        && !(((nYear % 100) == 0) || ((nYear % 400) == 0));
+        && (((nYear % 100) != 0) || ((nYear % 400) == 0));
 }
 
 static sal_uInt16
-- 
1.7.3.4