RFR: 8245194: Unix domain socket channel implementation [v20]

[Michael McMahon]

On Wed, 14 Oct 2020 12:28:04 GMT, Daniel Fuchs <dfuchs at openjdk.org> wrote:

>> Michael McMahon has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev
>> excludes the unrelated changes brought in by the merge/rebase. The pull request contains 22 additional commits since
>> the last revision:
>>  - Merge branch 'master' into unixdomainchannels
>>  - - reorganised the channel impls back into SocketChannelImpl and ServerSocketChannelImpl
>>    - removed the new Unix domain socket events and folded the behavior into the existing socket events
>>    - implemented other comments from Alan on Oct 11.
>>  - unixdomainchannels: updates from Chris's review 9 Oct 2020
>>  - unixdomainchannels:
>>    - updated property name
>>    - added JFR unit test
>>  - Merge branch 'master' into unixdomainchannels
>>  - - update after Alan's review on Oct 4
>>    - includes API change required by JDK-8251952
>>    - original CSR for the overall change will be resubmitted with
>>      all api changes consolidated based on this update
>>  - - simplified Copy.gmk to CAT source files directly
>>    - renamed net.properties source files to all be net.properties
>>  - unixdomainchannels: error in the last commit in make/modules/java.base/Copy.gmk
>>  - unixdomainchannels:
>>    (1) rename UnixDomainHelper to UnixDomainSocketsUtil
>>    (2) remove hardcoded /tmp and /var/tmp paths from UnixDomainSocketsUtil
>>    (3) replace (2) with documented system/networking properties
>>    (4) Small update to UnixDomainSocketAddress API
>>    (5) CSR for (3) and (4) submitted at JDK-8253930
>>    (6) Update build to generate net.properties from shared net.properties.common
>>        plus platform specific additions.
>>  - Merge branch 'master' into unixdomainchannels
>>  - ... and 12 more: https://git.openjdk.java.net/jdk/compare/1e93b2d3...7f677d5a
>
> src/java.base/unix/native/libnio/ch/UnixDomainSockets.c line 76:
> 
>> 74:     sa->sun_family = AF_UNIX;
>> 75:     int ret;
>> 76:     const char* pname = (const char *)(*env)->GetByteArrayElements(env, path, NULL);
> 
> Should `pname == NULL` be checked?

A UnixDomainSocketAddress should always always have a path associated and therefore a byte array should always be
present, but again I think this is no harm for overall robustness.

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PR: https://git.openjdk.java.net/jdk/pull/52