Merge "Fix race condition when getting cmdline" into stable/stein
This commit is contained in:
commit
57d9047f64
|
@ -323,19 +323,24 @@ def process_is_running(pid):
|
|||
def get_cmdline_from_pid(pid):
|
||||
if not process_is_running(pid):
|
||||
return []
|
||||
with open('/proc/%s/cmdline' % pid, 'r') as f:
|
||||
cmdline = f.readline().split('\0')[:-1]
|
||||
# NOTE(jh): Even after the above check, the process may terminate
|
||||
# before the open below happens
|
||||
try:
|
||||
with open('/proc/%s/cmdline' % pid, 'r') as f:
|
||||
cmdline = f.readline().split('\0')[:-1]
|
||||
except IOError:
|
||||
return []
|
||||
|
||||
# NOTE(slaweq): sometimes it may happen that values in
|
||||
# /proc/{pid}/cmdline are separated by space instead of NUL char,
|
||||
# in such case we would have everything in one element of cmdline_args
|
||||
# list and it would not match to expected cmd so we need to try to
|
||||
# split it by spaces
|
||||
if len(cmdline) == 1:
|
||||
cmdline = cmdline[0].split(' ')
|
||||
# NOTE(slaweq): sometimes it may happen that values in
|
||||
# /proc/{pid}/cmdline are separated by space instead of NUL char,
|
||||
# in such case we would have everything in one element of cmdline_args
|
||||
# list and it would not match to expected cmd so we need to try to
|
||||
# split it by spaces
|
||||
if len(cmdline) == 1:
|
||||
cmdline = cmdline[0].split(' ')
|
||||
|
||||
LOG.debug("Found cmdline %s for process with PID %s.", cmdline, pid)
|
||||
return cmdline
|
||||
LOG.debug("Found cmdline %s for process with PID %s.", cmdline, pid)
|
||||
return cmdline
|
||||
|
||||
|
||||
def cmd_matches_expected(cmd, expected_cmd):
|
||||
|
|
|
@ -336,6 +336,16 @@ class TestGetCmdlineFromPid(base.BaseTestCase):
|
|||
mock_open.assert_not_called()
|
||||
self.assertEqual([], cmdline)
|
||||
|
||||
def test_cmdline_process_disappearing(self):
|
||||
self.process_is_running_mock.return_value = True
|
||||
mock_open = self.useFixture(
|
||||
tools.OpenFixture('/proc/%s/cmdline' % self.pid, 'process')
|
||||
).mock_open
|
||||
mock_open.side_effect = IOError()
|
||||
cmdline = utils.get_cmdline_from_pid(self.pid)
|
||||
mock_open.assert_called_once_with('/proc/%s/cmdline' % self.pid, 'r')
|
||||
self.assertEqual([], cmdline)
|
||||
|
||||
|
||||
class TestFindChildPids(base.BaseTestCase):
|
||||
|
||||
|
|
Loading…
Reference in New Issue