Patch to expand tz checking scope in TimeZone_md.c

[Jonathan Lu]

On 11/02/2011 07:00 PM, David Holmes wrote:
> On 2/11/2011 7:01 PM, Jonathan Lu wrote:
>> On 11/02/2011 04:56 PM, Jonathan Lu wrote:
>>> Hi core-libs-dev,
>>>
>>> In jdk/src/solaris/native/java/util/TimeZone_md.c, starting from line
>>> 626, I found that the scope of "#ifdef __solaris__" might be too
>>> narrow, since it also works for some kind of OS which I'm currently
>>> working on, such as AIX.
>>> So I suggest to just remove the '#ifdef __solaris__' and leave the
>>> "#else" to accommodate more conditions, see attachment 'patch.diff'. I
>>> think this may enhance the cross-platform ability, any ideas about
>>> this modification?
>>>
>>> Regards
>>> - Jonathan Lu
>> I'm not sure why the attachment got filtered, here paste it to the mail
>> content directly.
>>
>> diff -r 4788745572ef src/solaris/native/java/util/TimeZone_md.c
>> --- a/src/solaris/native/java/util/TimeZone_md.c Mon Oct 17 19:06:53
>> 2011 -0700
>> +++ b/src/solaris/native/java/util/TimeZone_md.c Thu Oct 20 13:43:47
>> 2011 +0800
>> @@ -626,10 +626,8 @@
>> #ifdef __linux__
>> if (tz == NULL) {
>> #else
>> -#ifdef __solaris__
>> if (tz == NULL || *tz == '\0') {
>> #endif
>> -#endif
>> tz = getPlatformTimeZoneID();
>> freetz = tz;
>> }
>
> I'm unclear why any of that code needs to be platform specific - is an 
> empty TZ string somehow valid on linux? I would have thought the 
> following would be platform neutral:
>
>    if (tz == NULL || *tz == '\0') {
>         tz = getPlatformTimeZoneID();
>         freetz = tz;
>     }
>
Hi David,

getenv("TZ") returns NULL when TZ environment variable is not set at all 
and returns '\0' when TZ was exported as empty string. After more 
checking for both cases, I agree with you, nothing useful can be 
retrieved from that environment variable.
So I changed the patch to this,

diff -r 7ab0d613cd1a src/solaris/native/java/util/TimeZone_md.c
--- a/src/solaris/native/java/util/TimeZone_md.c    Thu Oct 20 10:32:47 
2011 -0700
+++ b/src/solaris/native/java/util/TimeZone_md.c    Wed Nov 02 19:34:51 
2011 +0800
@@ -623,13 +623,7 @@

      tz = getenv("TZ");

-#ifdef __linux__
-    if (tz == NULL) {
-#else
-#ifdef __solaris__
      if (tz == NULL || *tz == '\0') {
-#endif
-#endif
          tz = getPlatformTimeZoneID();
          freetz = tz;
      }

> David
> -----
>
>> Regards
>> - Jonathan Lu
Regards

- Jonathan