The default behavior for a real-time signal is to terminate the process.
If the child we fork sends a SIGRTMIN signal before we've set up the
ScopedSignalHandler for it, then the parent is terminated.
Test: adb shell /data/nativetest64/bionic-unit-tests-static/bionic-unit-tests-static --gtest_filter=spawn.signal_stress --gtest_repeat=1000
Bug: b/77554047
Change-Id: Ib44cbea8ccf506644405d8f426d9ad24e77cfa33
We saw crashes from pthread_exit+debuggerd on LP32
(https://issuetracker.google.com/72291624), and it seems like the
equivalent problem should exist with system(3). I fixed posix_spawn(3)
as part of that bug, so the easiest fix is probably to reuse that.
Bug: http://b/72470344
Test: ran tests
Change-Id: I05f838706f2b4a14ac3ee21292833e6c8579b0d4
This doesn't address `struct sigaction` and `sigaction`. That will
come later.
Bug: http://b/72493232
Test: ran tests
Change-Id: I4134346757ce3a4dac6feae413361cec16223386
The main motivation here is that the sigprocmask in pthread_exit wasn't
actually blocking the real-time signals, and debuggerd (amongst other
things) is using them. I wasn't able to write a test that actually won
that race but I did write an equivalent one for posix_spawn.
This also fixes all the uses of sigset_t where the sigset_t isn't
exposed to the outside (which we can't easily fix because it would be
an ABI change).
Bug: https://issuetracker.google.com/72291624
Test: ran tests
Change-Id: Ib6eebebc5a7b0150079f1cb79593247917dcf750
Add a new stress test, and fix the code to pass it. We need to ensure that
we reset signal handlers for caught signals before unblocking signals in
the child, we need to ensure that this happens even if you haven't passed
a pthread_spawn_attr_t, and we need to ensure that this happens if you
pass in an empty sigdefault set.
Bug: http://b/68707996
Test: ran tests
Change-Id: I348e9b17b1bdf221591da42c0ada133d98471d66