Hi,

On Mon, 2017-07-17 at 17:24 +0200, Jonatan Schlag wrote:
> This patch add two new functions:
> config_get_id_from_config()
> config_get_hook_from_config
> 
> Signed-off-by: Jonatan Schlag <jonatan.schlag(a)ipfire.org>
> ---
>  src/functions/functions.config | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
> 
> diff --git a/src/functions/functions.config
> b/src/functions/functions.config
> index 854f490..e11a1c2 100644
> --- a/src/functions/functions.config
> +++ b/src/functions/functions.config
> @@ -51,3 +51,23 @@ config_domainname() {
>  	# the domain part.
>  	print "${hostname#*.}"
>  }
> +
> +config_get_id_from_config() {
> +	# This function returns the id for a given config name
> +	# Example 'dhcp.0' => 0
> +	assert [ $# -eq 1 ]
> +	local config=${1}
> +
> +	local hook=$(config_get_hook_from_config ${config})
> +	echo "${config//"${hook}."/}"
> +
> +}

There is an extra empty line.

And calling config_get_hook_from_config() is an expensive call. It
forks a subshell and loads the hook and so on.

I am sure that you can find the ID without knowing what is coming
before. That would increase performance of this function tremendously.

> +
> +config_get_hook_from_config() {
> +	# This function returns the hook for a given config name
> +	# Example 'dhcp.0' => dhcp
> +	assert [ $# -eq 1 ]
> +	local config=${1}
> +
> +	echo "${config//.*[[:digit:]]/}"
> +}