i3-config/scripts/i3blocks/iface

#!/bin/bash
# Copyright (C) 2014 Julien Bonjean <julien@bonjean.info>
# Copyright (C) 2014 Alexander Keller <github@nycroth.com>
# Copyright (C) 2020 Jesús E. <heckyel@hyperbola.info>

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

#------------------------------------------------------------------------

# Use the provided interface, otherwise the device used for the default route.
IF="${IFACE:-$BLOCK_INSTANCE}"
IF="${IF:-$(ip route | awk '/^default/ { print $5 ; exit }')}"

# Exit if there is no default route
[[ -z "$IF" ]] && exit

#------------------------------------------------------------------------

# As per #36 -- It is transparent: e.g. if the machine has no battery or wireless
# connection (think desktop), the corresponding block should not be displayed.
[[ ! -d /sys/class/net/${IF} ]] && exit

#------------------------------------------------------------------------

LABEL="${LABEL:-}"

for flag in "$1" "$2"; do
    case "$flag" in
        -L)
            if [[ "$IF" = "" ]]; then
                LABEL="iface "
            else
                LABEL="$IF: "
            fi ;;
    esac
done

if [[ "$IF" = "" ]] || [[ "$(cat "/sys/class/net/$IF/operstate")" = 'down' ]];
then
    echo "${LABEL}down" # text
    echo \#FF0000 # color
    exit
fi

# Check local ip address
IPADDR=$(ip route get 4.2.2.1 | grep -oE "src [.0-9]+" | awk '{print $NF;exit}')

case $BLOCK_BUTTON in
    3) echo -n "$IPADDR" | xclip -q -se c ;;
esac

#------------------------------------------------------------------------

echo "$LABEL$IPADDR"