Use native IO objects & support blocking IO

byteit101 commented 5 years ago

(Note this PR is still WIP, and should NOT be merged until this check list is finished)

[x] Wait for JRuby 9.2.9.0 to be released
[x] Test on Mac OS X
[x] Upload Arduino test spec for HUPCL tests
[x] Fix API test spec to work on CI

This PR ditches the FFI calls to open & close in favor of using IO::for_fd so that we can use normal IO blocking & nonblocking methods. It still requires a bit of funkyness on windows, but it is working with MRI, and JRuby 9.2.8.0.dev + patches. This will fix #25 for the blocking, and will fix #36 as IO#flush works correctly out of the box now.

As part of this, I did some clean up of the API, and unfortunately this has some breaking changes for exceptions and return types. I went the safe way to minimize harm, but I still bumped the version to be cautious. Not sure if that's a good idea or not? Feedback greatly appreciated on that.

Third, I added lots of yard doc to all methods.

Fourth, I added a SerialPort class that enables compatibility on par with what the readme suggested already existed, but didn't quite.

Fifth, I added support for the HUPCL flag (Windows via DtrControl) to fix #15. Serial#reconfigure(hupcl: true|false) or SerialPort#hupcl= true|false

Sixth, I added a bunch more tests for HUPCL & general API stuff. Unfortunately I couldn't figure out a way to do this without a second program, so 1/3 of the tests now depend on an arduino project, though they are skipped if not detected.

That's all for now. The patches for JRuby are jnr/jnr-enxio:master and https://github.com/jruby/jruby/pull/5774 branch https://github.com/byteit101/jruby/tree/winio)