Fix one race condition between start and stop.

For a oneshot service, if start happens immediately after stop,
the service could be still in stopping status and then start
won't do anything. This fix this race condition.

Test: manual - see reproduce instructions in bug.
Bug: 68020256
Change-Id: I20202fa346f1949a8bda3d90deedc8b6a6d814d3
This commit is contained in:
Tao Wu 2017-10-26 10:43:10 -07:00
parent 41a9b3c81d
commit 990d43cb82

View file

@ -706,14 +706,20 @@ Result<Success> Service::ExecStart() {
}
Result<Success> Service::Start() {
bool disabled = (flags_ & (SVC_DISABLED | SVC_RESET));
// Starting a service removes it from the disabled or reset state and
// immediately takes it out of the restarting state if it was in there.
flags_ &= (~(SVC_DISABLED|SVC_RESTARTING|SVC_RESET|SVC_RESTART|SVC_DISABLED_START));
// Running processes require no additional work --- if they're in the
// process of exiting, we've ensured that they will immediately restart
// on exit, unless they are ONESHOT.
// on exit, unless they are ONESHOT. For ONESHOT service, if it's in
// stopping status, we just set SVC_RESTART flag so it will get restarted
// in Reap().
if (flags_ & SVC_RUNNING) {
if ((flags_ & SVC_ONESHOT) && disabled) {
flags_ |= SVC_RESTART;
}
// It is not an error to try to start a service that is already running.
return Success();
}