RFR: JDK-8184770: JDWP support for IPv6

[Alex Menkov]

Hi Daniel, Chris,

Unfortunately docs are out-dated (I plan to update it in JDK13).
In JDK9
https://bugs.openjdk.java.net/browse/JDK-8041435
changed the behavior - empty address (i.e. only port is specified) means 
"local connections only", "*" means "all available connections".
Then in JDK10 new "allow" option was introduced:
https://bugs.openjdk.java.net/browse/JDK-8061228
(it allows to specify list of addresses/subnets to accept connections from).

--alex

On 04/01/2019 06:40, Chris Hegarty wrote:
> 
> On 01/04/2019 10:51, Daniel Fuchs wrote:
>> Hi Arthur,
>>
>> Not directly related to Alex's original question but...
>>
>> On 30/03/2019 00:03, Arthur Eubanks wrote:
>>> We have some ipv6 patches as well in this area as well (as well as 
>>> other patches to support ipv6 only environments) that we're trying to 
>>> upstream. I don't understand the code myself, but it might be useful 
>>> to take a look:
>>> http://cr.openjdk.java.net/~aeubanks/jdwpipv6/webrev.00/index.html
>>
>> SocketTransportService.java:
>>
>> On my machine at least, InetAddress.getByName("localhost") and
>> InetAddress.getLocalHost() are quite different:
>>
>>
>> InetAddress.getByName("localhost") will return the loopback (127.0.0.1)
>> InetAddress.getLocalHost() returns the local hostname (dhcp-XXX-XXX...)
>>
>> If I'm not mistaken your changes in HostPort would transform something
>> that previously returned the loopback (no host specified) with something
>> that returns the local host name ("*" specified).
>>
>>
>> So I'm not sure these changes are quite right.
>> Maybe Alex will be able to confirm.
> 
> We need to consult the documentation for the command-line tools that
> exercise this code, or the higher-level API spec for the expected
> behavior of `*`, port-only specified, etc.
> 
> -Chris.