NSTimeZone.m Bug on Windows

[Roland Schwingel]

Hi...

After being busy with other things over a longer a period I pulled 
current gnustep sources today from CVS. There is the new function to 
init NSTimeZone from Windows data directly. Fine thing from the idea. 
But current implementation contained some bugs making it not working at 
all on non-english systems.

Attached you will find a patch to fix this problem.

What are the problems. Windows stores timezoneinformation in the 
registry. The current time zone (spelled in windows words) is stored in 
localized in the
registry at

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\TimeZoneInformation

The whole table in the registry containing all timezoneentries is stored in

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones

But here the keys are in english. The current code in NSTimeZone tryies 
to lookup the localized name among the unlocalized keys. This must fail 
on non english windows.

The localized name can be found underneath each entry in the last 
mentioned table. My patch now dives directly in the list and compares 
the correct entries. Additionally it fixes an impossible lookup for a 
timezone file named according to the windows names, which results in an 
annoying NSLog() error. Even if somedays GNUstep would have 
timezonefiles for windows it would find them anyway.

Hope this patch can be applied

Roland

PS: Anyway the work for the new NSTimeZone was a good idea (forgot who 
made it)

--- NSTimeZone.m        2004-05-12 10:01:16.000000000 +0200
+++ NSTimeZone.m.new    2004-05-12 19:02:09.000000000 +0200
@@ -96,6 +96,7 @@
 #include "Foundation/NSDate.h"
 #include "Foundation/NSDictionary.h"
 #include "Foundation/NSException.h"
+#include "Foundation/NSFileManager.h"
 #include "Foundation/NSLock.h"
 #include "Foundation/NSObject.h"
 #include "Foundation/NSProcessInfo.h"
@@ -490,7 +491,7 @@
                }
 
              fileName = [NSTimeZoneClass getTimeZoneFile: name];
-             if (fileName == nil)
+             if (fileName == nil || ![[NSFileManager defaultManager] 
fileExistsAtPath:fileName])
 #ifdef WIN32
                 {
                   zone = [[GSWindowsTimeZone alloc] initWithName:name data:0];
@@ -1234,8 +1235,8 @@
         if (ERROR_SUCCESS == RegOpenKeyEx(HKEY_LOCAL_MACHINE, \
         "SYSTEM\\CurrentControlSet\\Control\\TimeZoneInformation", 0, 
KEY_READ, &regkey))
           {
-            char buf[100];
-            DWORD bufsize=100;
+            char buf[255];
+            DWORD bufsize=255;
             DWORD type;
             if (ERROR_SUCCESS==RegQueryValueEx(regkey, "StandardName", 0, 
&type, buf, &bufsize))
               {
@@ -1720,73 +1721,164 @@
 
 - (id) initWithName: (NSString*)name data: (NSData*)data
 {
-  NSString *shortName;
-  HKEY regkey;
+  HKEY     regDirKey;
+  BOOL     isNT = NO,regFound=NO;
 
-  if ([name hasSuffix:@" Standard Time"])
-    {
-      shortName = [name substringWithRange:NSMakeRange(0,[name length]-14)];
-    }
+  /* Open the key in the local machine hive where the time zone data is 
stored. */
+  if (ERROR_SUCCESS == 
RegOpenKeyEx(HKEY_LOCAL_MACHINE,"SOFTWARE\\Microsoft\\Windows 
NT\\CurrentVersion\\Time Zones", 0, KEY_READ, &regDirKey))
+  {
+    isNT=YES;
+    regFound=YES;
+  }
   else
+  {
+    if (ERROR_SUCCESS == 
RegOpenKeyEx(HKEY_LOCAL_MACHINE,"SOFTWARE\\Microsoft\\Windows 
NT\\CurrentVersion\\Time Zones", 0, KEY_READ, &regDirKey))
     {
-      shortName = name;
+       regFound=YES;
     }
+  }
 
-  /* Open the key in the local machine hive where the time zone data is 
stored. */
-  if (ERROR_SUCCESS == RegOpenKeyEx(HKEY_LOCAL_MACHINE, \
-    [[NSString 
-    stringWithFormat:@"SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Time 
Zones\\%@", name] cString], 0, KEY_READ, &regkey) \
-    || ERROR_SUCCESS == RegOpenKeyEx(HKEY_LOCAL_MACHINE, \
-    [[NSString 
-    stringWithFormat:@"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Time 
Zones\\%@", shortName] cString], 0, KEY_READ, &regkey))
-    {
-      char buf[200];
-      DWORD bufsize=sizeof(buf);
-      DWORD type;
-
-      /* Read in the time zone data */
-      if (ERROR_SUCCESS==RegQueryValueEx(regkey, "TZI", 0, &type, buf, 
&bufsize))
-        {
-          TZI *tzi = (void*)buf;
-          Bias = tzi->Bias;
-          StandardBias = tzi->StandardBias;
-          DaylightBias = tzi->DaylightBias;
-          StandardDate = tzi->StandardDate;
-          DaylightDate = tzi->DaylightDate;
-        }
-      bufsize=sizeof(buf);
-      /* Read the standard name for the time zone. */
-      if (ERROR_SUCCESS==RegQueryValueEx(regkey, "Std", 0, &type, buf, 
&bufsize))
-        {
-          int a, b;
-          [timeZoneName release];
-          timeZoneName = [[NSString stringWithCString:buf] retain];
-          for(a=0,b=0;buf[a];a++)
-            {
-              if (isupper(buf[a]))
-                buf[b++]=buf[a];
-            }
-          buf[b]=0;
-          [timeZoneNameAbbr release];
-          timeZoneNameAbbr = [[NSString stringWithCString:buf] retain];
-        }
-      /* Read the daylight savings name for the time zone. */
-      if (ERROR_SUCCESS==RegQueryValueEx(regkey, "Dlt", 0, &type, buf, 
&bufsize))
-        {
-          int a,b;
-          [daylightZoneName release];
-          daylightZoneName = [[NSString stringWithCString:buf] retain];
-          for(a=0,b=0;buf[a];a++)
-            {
-              if (isupper(buf[a]))
-                buf[b++]=buf[a];
-            }
-          buf[b]=0;
-          [daylightZoneNameAbbr release];
-          daylightZoneNameAbbr = [[NSString stringWithCString:buf] retain];
-        }
-      RegCloseKey(regkey);
-    }
+  if (regFound)
+  {
+       /* Iterate over all subKeys in the registry to find the right one.
+          Unfortunately name is a localized value. The keys in the registry are
+          unlocalized names. */
+          CHAR     achKey[255];              // buffer for subkey name
+       DWORD    cbName;                   // size of name string 
+       CHAR     achClass[MAX_PATH] = "";  // buffer for class name 
+       DWORD    cchClassName = MAX_PATH;  // size of class string 
+       DWORD    cSubKeys=0;               // number of subkeys 
+       DWORD    cbMaxSubKey;              // longest subkey size 
+       DWORD    cchMaxClass;              // longest class string 
+       DWORD    cValues;                  // number of values for key 
+       DWORD    cchMaxValue;              // longest value name 
+       DWORD    cbMaxValueData;           // longest value data 
+       DWORD    cbSecurityDescriptor;     // size of security descriptor 
+       FILETIME ftLastWriteTime;          // last write time 
+               
+               DWORD i, retCode;
+               BOOL    tzFound = NO;
+               
+               /* Get the class name and the value count. */
+           retCode = RegQueryInfoKey(
+               regDirKey,               // key handle 
+               achClass,                // buffer for class name 
+               &cchClassName,           // size of class string 
+               NULL,                    // reserved 
+               &cSubKeys,               // number of subkeys 
+               &cbMaxSubKey,            // longest subkey size 
+               &cchMaxClass,            // longest class string 
+               &cValues,                // number of values for this key 
+               &cchMaxValue,            // longest value name 
+               &cbMaxValueData,         // longest value data 
+               &cbSecurityDescriptor,   // security descriptor 
+               &ftLastWriteTime);       // last write time 
+
+       if (cSubKeys && (retCode == ERROR_SUCCESS))
+       {
+               const char *cName = [name cString];
+
+                       for (i=0; i<cSubKeys && !tzFound; i++) 
+                       { 
+                          cbName = 255;
+                          
+                          retCode = RegEnumKeyEx(regDirKey, i, achKey, 
&cbName, NULL, NULL, NULL, &ftLastWriteTime);         
+                          if (retCode == ERROR_SUCCESS) 
+                          {
+                                char keyBuffer[16384];
+                                HKEY regKey;
+                              
+                              if (isNT)
+                               sprintf(keyBuffer,"SOFTWARE\\Microsoft\\Windows 
NT\\CurrentVersion\\Time Zones\\%s",achKey);
+                                        else
+                               
sprintf(keyBuffer,"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Time 
Zones\\%s",achKey);
+                              
+                         if (ERROR_SUCCESS == RegOpenKeyEx(HKEY_LOCAL_MACHINE, 
keyBuffer, 0, KEY_READ, &regKey))
+                              {
+                                     char buf[256];
+                                     char standardName[256];
+                                     char daylightName[256];
+                                     DWORD bufsize;
+                                     DWORD type;
+
+                                               /* check standardname */
+                                               standardName[0]='\0';
+                                     bufsize=sizeof(buf);
+                                     if 
(ERROR_SUCCESS==RegQueryValueEx(regKey, "Std", 0, &type, buf, &bufsize))
+                                     {
+                                       strcpy(standardName,buf);
+                                       if (strcmp(standardName,cName) == 0)
+                                               tzFound = YES;
+                                       }
+               
+                                               /* check daylightname */
+                                               daylightName[0]='\0';
+                                     bufsize=sizeof(buf);
+                                     if 
(ERROR_SUCCESS==RegQueryValueEx(regKey, "Dlt", 0, &type, buf, &bufsize))
+                                     {
+                                       strcpy(daylightName,buf);
+                                       if (strcmp(daylightName,cName) == 0)
+                                               tzFound = YES;
+                                       }
+
+                                               if (tzFound)
+                                               {
+                                             /* Read in the time zone data */
+                                             bufsize=sizeof(buf);
+                                             if 
(ERROR_SUCCESS==RegQueryValueEx(regKey, "TZI", 0, &type, buf, &bufsize))
+                                             {
+                                                 TZI *tzi = (void*)buf;
+                                                 Bias = tzi->Bias;
+                                                 StandardBias = 
tzi->StandardBias;
+                                                 DaylightBias = 
tzi->DaylightBias;
+                                                 StandardDate = 
tzi->StandardDate;
+                                                 DaylightDate = 
tzi->DaylightDate;
+                                             }
+                                             
+                                             /* Set the standard name for the 
time zone. */
+                                             if (strlen(standardName))
+                                             {
+                                                 int a, b;
+                                                 [timeZoneName release];
+                                                 timeZoneName = [[NSString 
stringWithCString:standardName] retain];
+
+                                                 /* Abbr generated here is 
IMHO a bit suspicous but I kept it */
+                                                 
for(a=0,b=0;standardName[a];a++)
+                                                 {
+                                                   if 
(isupper(standardName[a]))
+                                                     
standardName[b++]=standardName[a];
+                                                 }
+                                                 standardName[b]=0;
+                                                 [timeZoneNameAbbr release];
+                                                 timeZoneNameAbbr = [[NSString 
stringWithCString:standardName] retain];
+                                             }
+
+                                             /* Set the daylight savings name 
for the time zone. */
+                                             if (strlen(daylightName))
+                                             {
+                                                 int a,b;
+                                                 [daylightZoneName release];
+                                                 daylightZoneName = [[NSString 
stringWithCString:daylightName] retain];
+
+                                                 /* Abbr generated here is 
IMHO a bit suspicous but I kept it */
+                                                 
for(a=0,b=0;daylightName[a];a++)
+                                                 {
+                                                     if 
(isupper(daylightName[a]))
+                                                       
daylightName[b++]=daylightName[a];
+                                                 }
+                                                 daylightName[b]=0;
+                                                 [daylightZoneNameAbbr 
release];
+                                                 daylightZoneNameAbbr = 
[[NSString stringWithCString:daylightName] retain];
+                                       }
+                                       }
+                                     RegCloseKey(regKey);
+                               }                              
+                          }
+                       }
+       }
+      RegCloseKey(regDirKey);
+  }
+    
   return self;
 }