def test_shell_background_support_setsid():
"""In setsid mode, dumb-init should suspend itself and its children when it
receives SIGTSTP, SIGTTOU, or SIGTTIN.
"""
with print_signals() as (proc, pid):
for signum in SUSPEND_SIGNALS:
# both dumb-init and print_signals should be running or sleeping
assert process_state(pid) in ['running', 'sleeping']
assert process_state(proc.pid) in ['running', 'sleeping']
# both should now suspend
proc.send_signal(signum)
def assert_both_stopped():
assert process_state(
proc.pid) == process_state(pid) == 'stopped'
sleep_until(assert_both_stopped)
# and then both wake up again
proc.send_signal(SIGCONT)
assert (proc.stdout.readline() == '{}\n'.format(SIGCONT).encode(
'ascii'))
assert process_state(pid) in ['running', 'sleeping']
assert process_state(proc.pid) in ['running', 'sleeping']
def test_shell_background_support_setsid():
"""In setsid mode, dumb-init should suspend itself and its children when it
receives SIGTSTP, SIGTTOU, or SIGTTIN.
"""
with print_signals() as (proc, pid):
for signum in SUSPEND_SIGNALS:
# both dumb-init and print_signals should be running or sleeping
assert process_state(pid) in ['running', 'sleeping']
assert process_state(proc.pid) in ['running', 'sleeping']
# both should now suspend
proc.send_signal(signum)
def assert_both_stopped():
assert process_state(proc.pid) == process_state(pid) == 'stopped'
sleep_until(assert_both_stopped)
# and then both wake up again
proc.send_signal(SIGCONT)
assert (
proc.stdout.readline() == '{0}\n'.format(SIGCONT).encode('ascii')
)
assert process_state(pid) in ['running', 'sleeping']
assert process_state(proc.pid) in ['running', 'sleeping']
def test_setsid_signals_entire_group():
"""When dumb-init is running in setsid mode, it should signal the entire
process group rooted at it.
"""
pids = spawn_and_kill_pipeline()
def assert_no_living_pids():
assert len(living_pids(pids)) == 0
sleep_until(assert_no_living_pids)
def test_setsid_signals_entire_group():
"""When dumb-init is running in setsid mode, it should signal the entire
process group rooted at it.
"""
pids = spawn_and_kill_pipeline()
def assert_no_living_pids():
assert len(living_pids(pids)) == 0
sleep_until(assert_no_living_pids)
def test_no_setsid_doesnt_signal_entire_group():
"""When dumb-init is not running in setsid mode, it should only signal its
immediate child.
"""
pids = spawn_and_kill_pipeline()
def assert_four_living_pids():
assert len(living_pids(pids)) == 4
sleep_until(assert_four_living_pids)
for pid in living_pids(pids):
kill_if_alive(pid)
def test_no_setsid_doesnt_signal_entire_group():
"""When dumb-init is not running in setsid mode, it should only signal its
immediate child.
"""
pids = spawn_and_kill_pipeline()
def assert_four_living_pids():
assert len(living_pids(pids)) == 4
sleep_until(assert_four_living_pids)
for pid in living_pids(pids):
kill_if_alive(pid)
def spawn_and_kill_pipeline():
proc = Popen(('dumb-init', 'sh', '-c',
"yes 'oh, hi' | tail & yes error | tail >&2"))
def assert_living_pids():
assert len(living_pids(pid_tree(os.getpid()))) == 6
sleep_until(assert_living_pids)
pids = pid_tree(os.getpid())
proc.send_signal(signal.SIGTERM)
proc.wait()
return pids
def spawn_and_kill_pipeline():
proc = Popen((
'dumb-init',
'sh', '-c',
"yes 'oh, hi' | tail & yes error | tail >&2"
))
def assert_living_pids():
assert len(living_pids(pid_tree(os.getpid()))) == 6
sleep_until(assert_living_pids)
pids = pid_tree(os.getpid())
proc.send_signal(signal.SIGTERM)
proc.wait()
return pids