vdev_id: Return an error if config file is not found

[rugubara]

Motivation and Context

The udev helper is supposed to return 0 exit code only when it produced the stdout suitable for consumption by the udev rule. error messages and usage messages should produce non-zero exit code that guarantees udev rule ignores the stdout.

Description

How Has This Been Tested?

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Performance enhancement (non-breaking change which improves efficiency)
• Code cleanup (non-breaking change which makes code smaller or more readable)
• Breaking change (fix or feature that would cause existing functionality to change)
• Library ABI change (libzfs, libzfs_core, libnvpair, libuutil and libzfsbootenv)
• Documentation (a change to man pages or other documentation)

Checklist:

• My code follows the OpenZFS code style requirements.
• I have updated the documentation accordingly.
• I have read the contributing document.
• I have added tests to cover my changes.
• I have run the ZFS Test Suite with this change applied.
• All commit messages are properly formatted and contain Signed-off-by.

Signed-off-by: Anton Gubarkov anton.gubarkov@gmail.com

[tonyhutter]

I would change your commit message to:

vdev_id: Return an error if config file is not found

[tonyhutter]

You'll also need a Signed-off-by: line in your commit message with your name and email. For example, mine is:

Signed-off-by: Tony Hutter <hutter2@llnl.gov>

[rugubara]

You'll also need a Signed-off-by: line in your commit message with your name and email. For example, mine is:

I pushed another commit with the signed-off line. I'm not sure if it is updated everywhere...

[tonyhutter]

I think everything looks good. Could you squash your two commits into one commit? (git rebase -i master) I'll approve it after that.

[rugubara]

I think everything looks good. Could you squash your two commits into one commit? (git rebase -i master) I'll approve it after that.

I tried... not sure that it gave the expected result.
My fork now has in my master branch:

commit 0e8cfee5a107a280cb7f4367c4c0df28d7cc0bbd
Author: Anton Gubarkov <anton.gubarkov@gmail.com>
Date:   Wed Aug 18 12:56:12 2021 +0300

    vdev_id: Return an error if config file is not found

    Signed-off-by: Anton Gubarkov <anton.gubarkov@gmail.com>

diff --git a/cmd/vdev_id/vdev_id b/cmd/vdev_id/vdev_id
index d349ba43c..cad59c93f 100755
--- a/cmd/vdev_id/vdev_id
+++ b/cmd/vdev_id/vdev_id
@@ -140,7 +140,8 @@ Usage: vdev_id [-h]
   -p    number of phy's per switch port [default=$PHYS_PER_PORT]
   -h    show this summary
 EOF
-       exit 0
+       exit 1
+       # exit with error to avoid processing usage message by a udev rule
 }

 map_slot() {
@@ -728,7 +729,7 @@ done

 if [ ! -r "$CONFIG" ] ; then
        echo "Error: Config file \"$CONFIG\" not found"
-       exit 0
+       exit 1
 fi

 if [ -z "$DEV" ] && [ -z "$ENCLOSURE_MODE" ] ; then

I can't see this commit in this PR

[tonyhutter]

Ah I see, you created this PR on your master branch, which explains why the git rebase didn't work. Typically you create a separate branch for a PR. Here are the steps to create a separate branch with your commit in it:

# Create a new "vdev_id_error_code" branch on top of openzfs master
git remote add upstream https://github.com/openzfs/zfs.git 
git fetch upstream
git checkout upstream/master
git checkout -b vdev_id_error_code

# Include your vdev_id commit in this branch
git cherry-pick 0e8cfee5a

# Push your new branch out to github
git push -u origin vdev_id_error_code

After you run though these steps, you should then open this PR, click "edit" at the top right, and then change your branch from master to vdev_id_error_code.

[rugubara]

Please pardon my ignorance in git. I really understand now how short sighted I was creating a PR from my master branch.
The commands you've provided really allowed me to move my commit to a new branch in my fork of zfs. However, I can't make changes in the way this PR is created. I need to change the from part from rugubara/zfs:master to rugubara/zfs:vdev_id_error_code. This part is not changeable. I can change only the base branch. I think it's easier to create a new PR then. Please advise.

[tonyhutter]

@rugubara whoops, you're right, I thought you could change both the source and destination branch in github, but you can only change the destination branch. Just create a new PR with your new branch and I'll approve it.

[rugubara]

I'm closing this PR. The new one is #12508. I wonder if it is possible to break a link between this PR and the master branch of my fork...