Workaround adb disconnecting issue on macOS Sierra

keep-adb-running.sh

#!/bin/bash

cat << EOF
###########################################################
# Workaround adb disconnecting issue on macOS Sierra
#
# More info:
# https://code.google.com/p/android/issues/detail?id=219085
# credits to: hans...@meetme.com, vs...@google.com
###########################################################

EOF

function each_device() {
  DEVICES=( $(adb devices | tail -n +2 | cut -sf 1) )

  for DEVICE in ${DEVICES[@]}
  do
    adb -s ${DEVICE} $@
  done
}

function monitor_adb () {
  adb start-server
  echo "[$(date)] adb started"

  while [ "$(each_device shell echo 1)" ]; do sleep 5; done

  echo "[$(date)] adb is broken, restarting"

  adb kill-server
  adb start-server || adb start-server
  each_device reverse
}

while [ true ]; do time monitor_adb ; done

This revision works when more than one device is connected.