Remove use of at-async in SSLStream close

[quinnj]

Should fix #44. I can't quite remember why we called at-async from close to close the underlying IO, but it shouldn't make that much of a difference to run this inline w/o at-async and makes this not cause problems when run in finalizers.

[quinnj]

@dantaras, are you able to try this branch out and confirm your original issue in #44 is fixed?

[quinnj]

Or @ancapdev, it sounds like you've also seen the issue; can you try this branch and report back?

[ancapdev]

Or @ancapdev, it sounds like you've also seen the issue; can you try this branch and report back?

I can give it a go. My failures were on large quarterly batch jobs, using a lot of resources, and then failing once every couple of days. It's hard to test reliably without a quicker reproducible. Does the JuliaWeb team run any kind of soak testing?

[ancapdev]

I've not been able to come up with a smaller reproducible that triggers the issue, but the changes here can't make things worse, so maybe we can get that in and monitor?

A couple of questions

• The lock is still there, is there a reason we think that's okay?
• Is it okay to throw exceptions from finalizers?

[rossviljoen]

Won't close acquire the iolock, and therefore is not permitted in a finalizer either?

[ancapdev]

@quinnj Hi, it's been a while, is there a reason this wasn't merged?