Fix race condition when starting env_syncer in enter_chroot.sh.
Sometimes, two processes might start the env_syncer at the same time.
If this occurs, then the pid file will get overwritten and one of the
processes won't be killed.
I've also fixed the env_syncer to properly daemonize, such that
cbuildbot won't wait on the env_syncer to be killed before exiting.
This requires closing stdin, stderr, and stdout.
BUG=chromium-os:17680
TEST=Reproduce hang, and verify that this fixes the hang. Verify that
multiple chroots can be entered at the same time and that the
env_syncer is killed when the last chroot exits. Verify that
cbuildbot is not kept hanging even if the env_syncer doesn't
exit.
Change-Id: I3cb9fbdf47a406e818e12cf91593b8e3481aa578
Reviewed-on: http://gerrit.chromium.org/gerrit/4232
Reviewed-by: Ryan Cui <rcui@chromium.org>
Tested-by: David James <davidjames@chromium.org>
1 file changed
