RFR (S) 8201224: Make string buffer size dynamic

[Alex Menkov]

Hi Jc,

Calculation of the required buffer size ("old fashion way") looks 
error-prone.
I don't think we need to care about ancient SUSv2, I suppose C99 is 
supported by all (or almost all) compilers.

But if you want to keep the code SUSv2-compatible, you can do something like
   char dummy = 0;
   int requiredSize = snprintf(&dummy, sizeof(dummy), formatString,...);

Other note:
"if (obtained_size == len) " is useless
obtained_size is a result of snprintf(result, len, ...)
and snprintf returns number of chars _excluding_ terminating null, so 
obtained_size is always less than len.

--alex

On 08/10/2018 07:55, JC Beyler wrote:
> Hi all,
> 
> Anybody motivated to look at this change? :)
> 
> Webrev: http://cr.openjdk.java.net/~jcbeyler/8201224/webrev.01/ 
> <http://cr.openjdk.java.net/%7Ejcbeyler/8201224/webrev.01/>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8201224
> 
> Let me know what you think!
> Jc
> 
> 
> On Wed, Aug 8, 2018 at 11:34 AM JC Beyler <jcbeyler at google.com 
> <mailto:jcbeyler at google.com>> wrote:
> 
>     Hi all,
> 
>     Here is a revised webrev that only does the stated fix in the bug. I
>     filed https://bugs.openjdk.java.net/browse/JDK-8209153 for fixing
>     the style.
> 
>     Webrev: http://cr.openjdk.java.net/~jcbeyler/8201224/webrev.01/
>     <http://cr.openjdk.java.net/%7Ejcbeyler/8201224/webrev.01/>
>     Bug: https://bugs.openjdk.java.net/browse/JDK-8201224
> 
>     Let me know what you think!
> 
>     Thanks!
>     Jc
> 
>     On Fri, Aug 3, 2018 at 9:12 AM JC Beyler <jcbeyler at google.com
>     <mailto:jcbeyler at google.com>> wrote:
> 
>         Yes that was my train of thought as well (do it in various
>         webrevs and via various bugs for tracking). Is there a will or
>         interest to doing a few passes to just put these tests into the
>         same format once and for all? If so, I'll create a few bugs for
>         a few cleanup webrevs.
> 
>         On the other hand, often there is a worry that we lose history
>         due to the cleanup passes modifying each line of each file.
> 
>         Hence me asking before doing something like that :-)
>         Jc
> 
>         On Fri, Aug 3, 2018 at 7:45 AM Daniel D. Daugherty
>         <daniel.daugherty at oracle.com
>         <mailto:daniel.daugherty at oracle.com>> wrote:
> 
>              > Ps: A lot of these tests seem to be in GCC style (where
>             spaces are all
>              > over the place, 4 space indent, etc.), should we do a
>             one-pass per
>              > folder to make it into more standard hotspot style?
> 
>             If you do whitespace/style cleanups, please do them with a
>             separate bug.
> 
>             Dan
> 
> 
> 
>             On 8/3/18 12:11 AM, JC Beyler wrote:
>>             Hi all,
>>
>>             Small change to the locationToString method to make the
>>             string dynamically generated.
>>
>>             I added a bit of paranoia to handle the case where things
>>             might be changed so that an error would propagate to the test.
>>
>>             Igor asked me to also at least fix the NSK_VERIFY tests in
>>             the file.
>>
>>             Let me know what you think:
>>
>>             Webrev:
>>             http://cr.openjdk.java.net/~jcbeyler/8201224/webrev.00/
>>             <http://cr.openjdk.java.net/%7Ejcbeyler/8201224/webrev.00/>
>>             Bug: https://bugs.openjdk.java.net/browse/JDK-8201224
>>
>>             Thanks,
>>             Jc
>>
>>             Ps: A lot of these tests seem to be in GCC style (where
>>             spaces are all over the place, 4 space indent, etc.),
>>             should we do a one-pass per folder to make it into more
>>             standard hotspot style?
> 
> 
> 
>         -- 
> 
>         Thanks,
>         Jc
> 
> 
> 
>     -- 
> 
>     Thanks,
>     Jc
> 
> 
> 
> -- 
> 
> Thanks,
> Jc