Tuesday, March 8, 2011

How to automatically run checkpatch.pl when developing QEMU

The checkpatch.pl script was recently added to qemu.git as a way to scan patches for coding standard violations. You can automatically run checkpatch.pl when committing changes to git and abort if there are violations:

$ cd qemu
$ cat >.git/hooks/pre-commit
exec git diff --cached | scripts/checkpatch.pl --no-signoff -q -
$ chmod 755 .git/hooks/pre-commit

Any commit that violates the coding standard as checked by checkpatch.pl will be aborted. I am running with this git hook now and will post any tweaks I make to it.

Update: If you encounter a false positive because checkpatch.pl is complaining about code you didn't touch, use git commit --no-verify to override the pre-commit hook. Use this trick sparingly :-).