We weren't closing the streams after we were done reading or writing,
which is kind of essential. The easy way to fix this is to just use
g_output_stream_splice() to a GMemoryOutputStream rather than
hand-rolling it. This results in a substantial reduction of code
complexity.
A second serious issue is that we were marking the task as complete when
the process exits, but that's racy - there could still be data to read
from stdout. Fix this by just refcounting outstanding operations.
This code, not surprisingly, looks a lot like the "multi" test.
Next, because processes output binary data, I'd be forced to annotate
the char*/length pairs as (array) (element-type uint8). But rather than
doing that, it's *far* simpler to just use GBytes.
We need a version of this that actually validates as UTF-8, that will be
in the next patch.
There are a number of nice things this class brings:
0) Has a race-free termination API on all platforms (on UNIX, calls to
kill() and waitpid() are coordinated as not to cause problems).
1) Operates in terms of G{Input,Output}Stream, not file descriptors
2) Standard GIO-style async API for wait() with cancellation
3) Makes some simple cases easy, like synchronously spawning a
process with an argument list
4) Makes hard cases possible, like asynchronously running a process
with stdout/stderr merged, output directly to a file path
Much rewriting and code review from Ryan Lortie <desrt@desrt.ca>
https://bugzilla.gnome.org/show_bug.cgi?id=672102
