Re: [PATCH v4 5/6] common/config: Introduce _exit wrapper around exit command

["Darrick J. Wong" <djwong@kernel.org>]

On Wed, Apr 09, 2025 at 07:00:51AM +0000, Nirjhar Roy (IBM) wrote:
> We should always set the value of status correctly when we are exiting.
> Else, "$?" might not give us the correct value.
> If we see the following trap
> handler registration in the check script:
> 
> if $OPTIONS_HAVE_SECTIONS; then
>      trap "_kill_seq; _summary; exit \$status" 0 1 2 3 15
> else
>      trap "_kill_seq; _wrapup; exit \$status" 0 1 2 3 15
> fi
> 
> So, "exit 1" will exit the check script without setting the correct
> return value. I ran with the following local.config file:
> 
> [xfs_4k_valid]
> FSTYP=xfs
> TEST_DEV=/dev/loop0
> TEST_DIR=/mnt1/test
> SCRATCH_DEV=/dev/loop1
> SCRATCH_MNT=/mnt1/scratch
> 
> [xfs_4k_invalid]
> FSTYP=xfs
> TEST_DEV=/dev/loop0
> TEST_DIR=/mnt1/invalid_dir
> SCRATCH_DEV=/dev/loop1
> SCRATCH_MNT=/mnt1/scratch
> 
> This caused the init_rc() to catch the case of invalid _test_mount
> options. Although the check script correctly failed during the execution
> of the "xfs_4k_invalid" section, the return value was 0, i.e "echo $?"
> returned 0. This is because init_rc exits with "exit 1" without
> correctly setting the value of "status". IMO, the correct behavior
> should have been that "$?" should have been non-zero.
> 
> The next patch will replace exit with _exit.
> 
> Signed-off-by: Nirjhar Roy (IBM) <nirjhar.roy.lists@gmail.com>
> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
> Reviewed-by: Dave Chinner <dchinner@redhat.com>

Looks good now,
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

--D

> ---
>  common/config | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/common/config b/common/config
> index 79bec87f..7dd78dbe 100644
> --- a/common/config
> +++ b/common/config
> @@ -96,6 +96,15 @@ export LOCAL_CONFIGURE_OPTIONS=${LOCAL_CONFIGURE_OPTIONS:=--enable-readline=yes}
>  
>  export RECREATE_TEST_DEV=${RECREATE_TEST_DEV:=false}
>  
> +# This functions sets the exit code to status and then exits. Don't use
> +# exit directly, as it might not set the value of "$status" correctly, which is
> +# used as an exit code in the trap handler routine set up by the check script.
> +_exit()
> +{
> +	test -n "$1" && status="$1"
> +	exit "$status"
> +}
> +
>  # Handle mkfs.$fstyp which does (or does not) require -f to overwrite
>  set_mkfs_prog_path_with_opts()
>  {
> -- 
> 2.34.1
> 
>