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>
This adds a couple of helper functions for working within Android:
- in_android(): Crude test that uses getenv() to see if an Android-
specific environment variable is defined.
- android_tmpdir_path(): Android doesn't have the usual locations for
temporary file storage such as /tmp or even /var/run/locks. And to
make matters worse, there isn't even a standard location for
temporary files so it must be determined at run time.
This will be used in a follow-up patch.
BUG=chrome-os-partner:49527
BRANCH=none
TEST=tested on smaug
Change-Id: Ifb5fb4067fffb7c8cb2d4350ca4a223e884d3aa5
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/329299
Reviewed-by: Shawn N <shawnn@chromium.org>
Instead of hardcoding the common files for host utils in the generic
rules, let's declare them in the build.mk file using the same system as
the Linux kernel build.
if a binary "foo" declared in "host-util-bin" or "build-util-bin" has a
matching "foo-objs" variable, it will be build from all objects declared
in "foo-objs" else it uses directly "foo.o" (single source file).
This is preparatory to add new "build" tools sharing common sources.
note: the dependencies on the utils are a bit less fine-grained as a
result of this change, but given the low number of tools, that should be
acceptable.
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
BRANCH=none
BUG=none
TEST=./util/make_all.sh
Change-Id: Ieffce7ca6f5b685ffb7d1f4626b99aff07b61443
Reviewed-on: https://chromium-review.googlesource.com/176174
Reviewed-by: Vic Yang <victoryang@chromium.org>
Commit-Queue: Vincent Palatin <vpalatin@chromium.org>
Tested-by: Vincent Palatin <vpalatin@chromium.org>
Basically re-use the gec lock code from flashrom package.
BUG=chrome-os-partner:12319
TEST=Build and run on link. Only build on snow.
while true; do ectool hello; done & ; run 10 instances.
; expect all instances runs okay.
Signed-off-by: Louis Yung-Chieh Lo <yjlou@chromium.org>
Change-Id: I11d5824f46810c6f5a04a564a81387cdea081697
Reviewed-on: https://gerrit.chromium.org/gerrit/29763
Reviewed-by: Randall Spangler <rspangler@chromium.org>
