Some pty tests persistently hung on the AIX CI buildbots. Fix that by
adding a helper script that properly sets up the pty before spawning
the script under test.
On investigation I discovered that the test runner hung when it tried
to close the slave pty's file descriptor, probably due to a bug in
AIX's pty implementation. I could reproduce it with a short C program.
The test runner also leaked file descriptors to the child process.
I couldn't convince python's `subprocess.Popen()` to do what I wanted
it to do so I opted to move the logic to a helper script that can do
fork/setsid/etc. without having to worry about stomping on state in
tools/test.py.
In the process I also uncovered some bugs in the pty module of the
python distro that ships with macOS 10.14, leading me to reimplement
a sizable chunk of the functionality of that module.
And last but not least, of course there are differences between ptys
on different platforms and the helper script has to paper over that.
Of course.
Really, this commit took me longer to put together than I care to admit.
Caveat emptor: this commit takes the hacky ^D feeding to the slave out
of tools/test.py and puts it in the *.in input files. You can also feed
other control characters to tests, like ^C or ^Z, simply by inserting
them into the corresponding input file. I think that's nice.
Fixes: https://github.com/nodejs/build/issues/1820
Fixes: https://github.com/nodejs/node/issues/28489
PR-URL: https://github.com/nodejs/node/pull/28600
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Allow reading from stdio streams that are conventionally
associated with process output, since this is only convention.
This involves disabling the oddness around closing stdio
streams. Its purpose is to prevent the file descriptors
0 through 2 from being closed, since doing so can lead
to information leaks when new file descriptors are being
opened; instead, not doing anything seems like a more
reasonable choice.
Fixes: https://github.com/nodejs/node/issues/21203
PR-URL: https://github.com/nodejs/node/pull/23053
Reviewed-By: James M Snell <jasnell@gmail.com>