Re: [PATCH v4 01/11] common/rc: Add _min() and _max() helpers

[David Laight <david.laight.linux@gmail.com>]

On Sun, 10 Aug 2025 19:11:52 +0530
Ojaswin Mujoo <ojaswin@linux.ibm.com> wrote:

> Many programs open code these functionalities so add it as a generic helper
> in common/rc
> 
> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
> Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
> ---
>  common/rc | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/common/rc b/common/rc
> index 96578d15..3858ddce 100644
> --- a/common/rc
> +++ b/common/rc
> @@ -5873,6 +5873,28 @@ _require_program() {
>  	_have_program "$1" || _notrun "$tag required"
>  }
>  
> +_min() {
> +	local ret
> +
> +	for arg in "$@"; do
> +		if [ -z "$ret" ] || (( $arg < $ret )); then
> +			ret="$arg"
> +		fi
> +	done
> +	echo $ret
> +}

Perhaps:
	local ret="$1"
	shift
	for arg in "$@"; do
		ret=$(((arg) < (ret) ? (arg) : (ret)))
	done;
	echo "$ret"
that should work for 'min 10 "2 + 3"' (with bash, but not dash).

	David

> +
> +_max() {
> +	local ret
> +
> +	for arg in "$@"; do
> +		if [ -z "$ret" ] || (( $arg > $ret )); then
> +			ret="$arg"
> +		fi
> +	done
> +	echo $ret
> +}
> +
>  ################################################################################
>  # make sure this script returns success
>  /bin/true