RFR: 8232571: Add missing SIGINFO signal

[Benoit Daloze]

Hello,

My use-case is implementing the Ruby language on top of the JVM with 
TruffleRuby.

JRuby also needs this. Without this fix, the SIGINFO signal cannot be 
trapped from Ruby's Signal.trap() method.

SIGINFO is frequently used on macOS by applications as it is easily 
generated by Ctrl+T in the terminal.

We have a test in TruffleRuby testing every signal we know about, and 
this is the only missing one.
Some signals cannot be trapped, we have to live with that, but signals 
should at least be recognized by new Signal().

Best regards,
Benoit Daloze

On 10/18/19 5:35 PM, Roger Riggs wrote:
> Hi Benoit,
>
> Can you provide the use case.
> Generally, only a limited subset of POSIX signals are implemented.
>
> Thanks, Roger
>
>
> On 10/18/19 11:27 AM, Benoit Daloze wrote:
>> Hello,
>>
>> Please review the following fix for 
>> https://bugs.openjdk.java.net/browse/JDK-8232571
>>
>> In short, new sun.misc.Signal("INFO") throws IllegalArgumentException 
>> on JDK11+
>> due to the signal not being in the known signal list. This is a 
>> regression, it worked fine in JDK8.
>>
>> I attach a patch to fix this,.
>>
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8232571
>>
>> Thanks,
>> Benoit Daloze
>