Gettimezoneinformation: use registry when available

[Rein Klazes]

hi,

Daylight saving time is ending here in two weeks. Time to start fixing
wine's deficiency with returning proper time zone information.

My idea is to get the info from the registry like Windows does. That
will work now of course only when used with an existing windows install.
Later add the possibility to configure time zone in winecfg.

Changelog:
	dlls/ntdll : time.c
	In RtlQueryTimezoneInformation use information from the registry
	if it is available.

Rein.
-- 
Rein Klazes
rklazes at xs4all.nl
-------------- next part --------------
--- wine/dlls/ntdll/time.c	2004-10-05 08:02:54.000000000 +0200
+++ mywine/dlls/ntdll/time.c	2004-10-16 22:32:47.000000000 +0200
@@ -58,6 +58,25 @@
 };
 static CRITICAL_SECTION TIME_GetBias_section = { &critsect_debug, -1, 0, 0, 0, 0 };
 
+/* TimeZone registry key values */
+static const WCHAR TZInformationKeyW[] = { 'M','a','c','h','i','n','e','\\',
+ 'S','Y','S','T','E','M','\\','C','u','r','r','e','n','t','C','o','n','t','r',
+ 'o','l','S','e','t','\\','C','o','n','t','r','o','l','\\','T','i','m','e','z',
+ 'o','n','e','I','n','f','o','r','m','a','t','i','o','n', 0};
+static const WCHAR TZStandardStartW[] = {
+  'S','t','a','n','d','a','r','d','s','t','a','r','t', 0};
+static const WCHAR TZDaylightStartW[] = {
+  'D','a','y','l','i','g','h','t','s','t','a','r','t', 0};
+static const WCHAR TZDaylightBiasW[] = {
+    'D','a','y','l','i','g','h','t','B','i','a','s', 0};
+static const WCHAR TZStandardBiasW[] = {
+    'S','t','a','n','d','a','r','d','B','i','a','s', 0};
+static const WCHAR TZBiasW[] = {'B','i','a','s', 0};
+static const WCHAR TZDaylightNameW[] = {
+    'D','a','y','l','i','g','h','t','N','a','m','e', 0};
+static const WCHAR TZStandardNameW[] = {
+    'S','t','a','n','d','a','r','d','N','a','m','e', 0};
+
 
 #define SETTIME_MAX_ADJUST 120
 
@@ -780,6 +799,62 @@
    return NULL;
 }
 
+/***  TIME_GetTimeZoneInfoFromReg: helper for GetTimeZoneInformation ***/
+
+
+static int TIME_GetTimeZoneInfoFromReg(LPTIME_ZONE_INFORMATION tzinfo)
+{
+    BYTE buf[90];
+    KEY_VALUE_PARTIAL_INFORMATION * KpInfo =
+        (KEY_VALUE_PARTIAL_INFORMATION *) buf;
+    HKEY hkey;
+    DWORD size;
+    OBJECT_ATTRIBUTES attr;
+    UNICODE_STRING nameW;
+
+    attr.Length = sizeof(attr);
+    attr.RootDirectory = 0;
+    attr.ObjectName = &nameW;
+    attr.Attributes = 0;
+    attr.SecurityDescriptor = NULL;
+    attr.SecurityQualityOfService = NULL;
+    RtlInitUnicodeString( &nameW, TZInformationKeyW);
+    if (!NtOpenKey( &hkey, KEY_ALL_ACCESS, &attr )) {
+
+#define GTZIFR_N( valkey, tofield) \
+        RtlInitUnicodeString( &nameW, valkey );\
+        if (!NtQueryValueKey( hkey, &nameW, KeyValuePartialInformation, KpInfo,\
+                    sizeof(buf), &size )) { \
+            if( size >= (sizeof((tofield)) + \
+                    offsetof(KEY_VALUE_PARTIAL_INFORMATION,Data))); { \
+                memcpy(&(tofield), \
+                        KpInfo->Data, sizeof(tofield)); \
+            } \
+        }
+#define GTZIFR_S( valkey, tofield) \
+        RtlInitUnicodeString( &nameW, valkey );\
+        if (!NtQueryValueKey( hkey, &nameW, KeyValuePartialInformation, KpInfo,\
+                    sizeof(buf), &size )) { \
+            strncpyW( tofield, (WCHAR*) KpInfo->Data, \
+                    sizeof( tofield) / sizeof(WCHAR) ); \
+        }
+        
+        GTZIFR_N( TZStandardStartW,  tzinfo->StandardDate)
+        GTZIFR_N( TZDaylightStartW,  tzinfo->DaylightDate)
+        GTZIFR_N( TZBiasW,          tzinfo->Bias)
+        GTZIFR_N( TZStandardBiasW,  tzinfo->StandardBias)
+        GTZIFR_N( TZDaylightBiasW,  tzinfo->DaylightBias)
+        GTZIFR_S( TZStandardNameW, tzinfo->StandardName)
+        GTZIFR_S( TZDaylightNameW, tzinfo->DaylightName)
+
+#undef GTZIFR_N
+#undef GTZIFR_S
+        NtClose( hkey );
+        return 1;
+    }
+    return 0;
+}
+
 /***********************************************************************
  *      RtlQueryTimeZoneInformation [NTDLL.@]
  *
@@ -800,14 +875,19 @@
 
     memset(tzinfo, 0, sizeof(TIME_ZONE_INFORMATION));
 
-    gmt = time(NULL);
-    bias = TIME_GetBias(gmt, &daylight);
+    if( !TIME_GetTimeZoneInfoFromReg(tzinfo)) {
+
+        gmt = time(NULL);
+        bias = TIME_GetBias(gmt, &daylight);
 
-    tzinfo->Bias = -bias / 60;
-    tzinfo->StandardBias = 0;
-    tzinfo->DaylightBias = -60;
-    psTZ = TIME_GetTZAsStr (gmt, (-bias/60), daylight);
-    if (psTZ) strcpyW( tzinfo->StandardName, psTZ );
+        tzinfo->Bias = -bias / 60;
+        tzinfo->StandardBias = 0;
+        tzinfo->DaylightBias = -60;
+        tzinfo->StandardName[0]='\0';
+        tzinfo->DaylightName[0]='\0';
+        psTZ = TIME_GetTZAsStr (gmt, (-bias/60), daylight);
+        if (psTZ) strcpyW( tzinfo->StandardName, psTZ );
+        }
     return STATUS_SUCCESS;
 }