This adds a fallback directory in case SYSTEM_LOCKFILE_DIR is
unavailable. Since this is a band-aid meant to help older systems
auto-update, the fallback path is hardcoded to "/tmp" as to avoid
polluting the overall lockfile API.
BUG=chromium:616620
BRANCH=none
TEST=Tested on veyron_jaq by removing /run/lock and seeing
mosys, flashrom, and ectool run successfully with
firmware_utility_lock in /tmp.
Change-Id: Idbe63a574474ec35a5c3b6fe2b0fb3b672941492
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/348850
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Some systems, such as Android, do not support SysV semaphore locks.
This implements an alternative file lock mechanism using flock().
flock() was chosen because it's pretty straight forward. It's known to
be broken when using NFS, but I doubt we'll ever store our lock on an
NFS volume.
CQ-DEPEND=CL:327407,CL:325609
BUG=chrome-os-partner:49527
BRANCH=none
TEST=tested on Smaug by running mosys and ectool while reading
firmware ROM with flashrom, all three utilities eventually
ran successfully.
Change-Id: Ic73fe0281fbc1dfaae1bb03e5683774a0c04ae5b
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/329430
Reviewed-by: Shawn N <shawnn@chromium.org>