[arch-projects] [netctl][PATCH] Support dynamically appearing interfaces

[Jouke Witteveen]

On Tue, Feb 12, 2013 at 1:40 PM, Ivan Shapovalov <intelfx100 at gmail.com> wrote:
> If a profile is WantedBy=multi-user.target, it breaks init sequence
> if its interface is not immediately available at runtime
> (e. g. a cell-phone or USB modem).

Does this work? Is there a reason not to make the device the default trigger?

>
> Add a parameter "DynamicProfileStart=" which, if enabled,
> makes the profile unit wanted by its interface unit
> (and not multi-user.target).
> ---
>  docs/netctl.profile.5.txt |  4 ++++
>  src/netctl                | 14 ++++++++++++--
>  2 files changed, 16 insertions(+), 2 deletions(-)
>
> diff --git a/docs/netctl.profile.5.txt b/docs/netctl.profile.5.txt
> index efd4fb4..73d99f9 100644
> --- a/docs/netctl.profile.5.txt
> +++ b/docs/netctl.profile.5.txt
> @@ -85,6 +85,10 @@ GENERAL OPTIONS
>      A command that is executed after a connection is brought down.
>      Similar precautions should be taken as with 'ExecUpPost'.
>
> +'DynamicProfileStart='::
> +    If ``yes`', the profile unit file is wanted by its interface unit file
> +    instead of *multi-user.target*. This is needed if the interface
> +    may appear dynamically (e. g. cell phone modem).
>
>  IP OPTIONS
>  ----------
> diff --git a/src/netctl b/src/netctl
> index 498b50d..787a621 100755
> --- a/src/netctl
> +++ b/src/netctl
> @@ -97,8 +97,18 @@ unit_enable() {
>      if [[ -n $After ]]; then
>          printf 'After="netctl@%s.service"\n' "${After[@]//\"/\\\"}" >>
> "$unit"
>      fi
> -    echo "ln -s '$unit' '${unit/system\//system/multi-user.target.wants/}'"
> -    ln -s "$unit" "${unit/system\//system/multi-user.target.wants/}"
> +
> +    local trigger="multi-user.target"
> +    if is_yes "${DynamicProfileStart:-no}"; then
> +        trigger="sys-subsystem-net-devices-${Interface/-/\\x2d}.device"
> +    fi
> +
> +    trigger="${unit/system\//system/$trigger.wants/}"
> +
> +    echo "mkdir -p '$(dirname "$trigger")'"
> +    mkdir -p "$(dirname "$trigger")"
> +    echo "ln -s '$unit' '$trigger'"
> +    ln -s "$unit" "$trigger"
>      systemctl daemon-reload
>  }
>
> --
> 1.8.1.3