Simplify timezone-related code and fix some minor bugs in it.

Try to make the chain of preprocessor checks for different ways of getting
time zone from the CRT more clear.

Also call _tzset() for all MSVC versions, not just MSVC8+ (closes #12700). We
should probably call tzset() for the other compilers too, in fact.

And multiply the timezone returned from ftime() by 60 as it's supposed to be
in minutes and not seconds as needed.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66245 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

diff --git a/src/common/datetime.cpp b/src/common/datetime.cpp
index 2d60ee2d981a06e3e9d580889b2510a0b0a588e6..49bfa98e1a61487ef90a8e387214a46b76737d10 100644 (file)
--- a/src/common/datetime.cpp
+++ b/src/common/datetime.cpp
@@ -117,44 +117,18 @@ wxCUSTOM_TYPE_INFO(wxDateTime, wxToStringConverter<wxDateTime> , wxFromStringCon
     #include <wtime.h>
 #endif
 
-#if !defined(WX_TIMEZONE) && !defined(WX_GMTOFF_IN_TM)
-    #if defined(__WXPALMOS__)
-        #define WX_GMTOFF_IN_TM
-    #elif defined(__BORLANDC__) || defined(__MINGW32__) || defined(__VISAGECPP__)
-        #define WX_TIMEZONE _timezone
-    #elif defined(__MWERKS__)
-        long wxmw_timezone = 28800;
-        #define WX_TIMEZONE wxmw_timezone
-    #elif defined(__DJGPP__) || defined(__WINE__)
-        #include <sys/timeb.h>
-        #include <values.h>
-        static long wxGetTimeZone()
-        {
-            struct timeb tb;
-            ftime(&tb);
-            return tb.timezone;
-        }
-        #define WX_TIMEZONE wxGetTimeZone()
-    #elif defined(__DARWIN__)
-        #define WX_GMTOFF_IN_TM
-    #elif wxCHECK_VISUALC_VERSION(8)
-        // While _timezone is still present in (some versions of) VC CRT, it's
-        // deprecated and _get_timezone() should be used instead.
-        static long wxGetTimeZone()
-        {
-            // We must initialize the time zone information before using it
-            // (this will be done only once internally).
-            _tzset();
+#if defined(__DJGPP__) || defined(__WINE__)
+    #include <sys/timeb.h>
+    #include <values.h>
+#endif
 
-            long t;
-            _get_timezone(&t);
-            return t;
-        }
-        #define WX_TIMEZONE wxGetTimeZone()
-    #else // unknown platform - try timezone
-        #define WX_TIMEZONE timezone
+#ifndef WX_GMTOFF_IN_TM
+    // Define it for some systems which don't (always) use configure but are
+    // known to have tm_gmtoff field.
+    #if defined(__WXPALMOS__) || defined(__DARWIN__)
+        #define WX_GMTOFF_IN_TM
     #endif
-#endif // !WX_TIMEZONE && !WX_GMTOFF_IN_TM
+#endif
 
 // NB: VC8 safe time functions could/should be used for wxMSW as well probably
 #if defined(__WXWINCE__) && defined(__VISUALC8__)
@@ -380,8 +354,33 @@ int GetTimeZone()
         gmtoffset = -tm.tm_gmtoff;
     }
     return (int)gmtoffset;
-#else // !WX_GMTOFF_IN_TM
+#elif defined(__DJGPP__) || defined(__WINE__)
+    struct timeb tb;
+    ftime(&tb);
+    return tb.timezone*60;
+#elif defined(__VISUALC__)
+    // We must initialize the time zone information before using it (this will
+    // be done only once internally).
+    _tzset();
+
+    // Starting with VC++ 8 timezone variable is deprecated and is not even
+    // available in some standard library version so use the new function for
+    // accessing it instead.
+    #if wxCHECK_VISUALC_VERSION(8)
+        long t;
+        _get_timezone(&t);
+        return t;
+    #else // VC++ < 8
+        return timezone;
+    #endif
+#elif defined(WX_TIMEZONE) // If WX_TIMEZONE was defined by configure, use it.
     return WX_TIMEZONE;
+#elif defined(__BORLANDC__) || defined(__MINGW32__) || defined(__VISAGECPP__)
+    return _timezone;
+#elif defined(__MWERKS__)
+    return 28800;
+#else // unknown platform -- assume it has timezone
+    return timezone;
 #endif // WX_GMTOFF_IN_TM/!WX_GMTOFF_IN_TM
 }