RFR: 8146879: Add option for handling existing log files in UL (was: Truncate new UL log files)

[Marcus Larsson]

Hi again,

Taking a different approach to this.

New webrev:
http://cr.openjdk.java.net/~mlarsson/8146879/webrev.01/

Existing files will now by default be renamed/archived with a .X suffix 
where X is the lowest number such that the resulting file name is 
available (jvm.log becomes jvm.log.0). A mode option for controlling 
this behavior has been added as well. It can be set to archive, append, 
or truncate (i.e. -Xlog::jvm.log::mode=truncate).

Tested with included jtreg test through JPRT.

Thanks,
Marcus

On 01/14/2016 04:00 PM, Marcus Larsson wrote:
> Hi,
>
> Please review the following patch to make sure UL truncates existing 
> log files before writing to them. Since files are opened in append 
> mode, truncation isn't done automatically, so instead the patch adds 
> an attempt to remove the log file before opening it.
>
> Webrev:
> http://cr.openjdk.java.net/~mlarsson/8146879/webrev.00/
>
> Issue:
> https://bugs.openjdk.java.net/browse/JDK-8146879
>
> Testing:
> Included test through JPRT
>
> Thanks,
> Marcus