Add contrib/net-speed

A reimplementation of contrib/measure-net-speed.bash.

- Single script
- Compatible with most POSIX shells, tested with bash, dash, busybox ash
- Auto detect interfaces
- Does not write temp files

diff --git a/contrib/net-speed b/contrib/net-speed
new file mode 100755 (executable)
index 0000000..3b7b30b
--- /dev/null
+++ b/contrib/net-speed
@@ -0,0 +1,105 @@
+#!/bin/sh
+# Copyright (c) 2014 Zhong Jianxin <azuwis@gmail.com>
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+# Thank Stefan Breunig for the original implementation, see
+# contrib/measure-net-speed.bash.
+
+# i3status.conf should contain:
+# general {
+#   output_format = i3bar
+# }
+
+# i3 config looks like this:
+# bar {
+#   status_command exec /usr/share/doc/i3status/contrib/net-speed
+# }
+
+# Single interface
+#ifaces="eth0"
+
+# Multiple interfaces
+#ifaces="eth0 wlan0"
+
+# Auto detect
+ifaces=$(ls /sys/class/net | grep -E '^(eth|wlan)')
+
+# Interval must be the same as in i3status.conf
+#interval=5
+
+# Auto detect
+if [ -f ~/.i3status.conf ]; then
+  i3status_conf=~/.i3status.conf
+else
+  i3status_conf="/etc/i3status.conf"
+fi
+interval=$(grep -o '^[[:space:]]*interval[[:space:]]*=[[:space:]]*[[:digit:]]\+' $i3status_conf | grep -o '[[:digit:]]\+')
+if [ x"$interval" = x ]; then
+  interval=5
+fi
+
+last_rx=0
+last_tx=0
+rate=""
+
+readable() {
+    local byte=$1
+    local kib=$(( byte >> 10 ))
+    if [ "$kib" -gt 1024 ]; then
+        local mib_int=$(( kib >> 10 ))
+        local mib_dec=$(( kib % 1024 * 976 / 10000 ))
+        if [ "$mib_dec" -lt 10 ]; then
+            mib_dec="0${mib_dec}"
+        fi
+        echo "${mib_int}.${mib_dec}M"
+    else
+        echo "${kib}K"
+    fi
+}
+
+update_rate() {
+    local rx=0
+    local tx=0
+    for iface in $ifaces; do
+        local tmp_rx
+        local tmp_tx
+        local stat="/sys/class/net/${iface}/statistics"
+        read tmp_rx < "${stat}/rx_bytes"
+        read tmp_tx < "${stat}/tx_bytes"
+        rx=$(( rx + tmp_rx ))
+        tx=$(( tx + tmp_tx ))
+    done
+    rate="$(readable $(( (rx - last_rx) / interval )))↓ $(readable $(( (tx - last_tx) / interval )))↑"
+    last_rx=$rx
+    last_tx=$tx
+}
+
+# while :; do
+#     update_rate
+#     echo "$rate"
+#     sleep "$interval"
+# done
+
+i3status | (read line && echo "$line" && read line && echo "$line" && read line && echo "$line" && update_rate && while :
+do
+    read line
+    update_rate
+    echo ",[{\"full_text\":\"${rate}\" },${line#,\[}" || exit 1
+done)