set CPU limit to flash player!

set-cpu-limit-to-flash-player.sh

#!/bin/bash
# A.J <andrwj@gmail.com>
# 2013-12-27
# v0.0.6
#
# set cpu limit to Flash player!
# default limit value: 30%
# usage:
#      set-cpu-limit-to-flash-player.sh 50
#
# NOTE: It assumes you play flash contents in Safari or Chrome.
# NOTE: `brew` should be on your system.

temporary_list_file="/tmp/$$.list"
previous_cpulimit_pid_file="/tmp/$$.dup"
webkitpluginhost_path="/System/Library/Frameworks/WebKit.framework/WebKitPluginHost.app/Contents/MacOS/WebKitPluginHost"
chromehelper_name="Google Chrome Helper"
limit=${1:-30}
cmd=/usr/local/bin/cpulimit

# don't left garbage ..
function clean_up {
    rm -f $temporary_list_file
    rm -f $previous_cpulimit_pid_file
    echo " "
}
trap clean_up SIGHUP SIGINT SIGTERM

if [[ ! -e "$cmd" ]]; then
    echo "- compile and install: cpulimit ..."
    brew install cpulimit
    if [[ $? -ne 0 ]]; then
        echo
        echo "- cpulimit is not presented. abort ";
        echo
        clean_up
    fi
    echo
fi

ps -ax | grep WebKitPluginHost | grep "$webkitpluginhost_path" > $temporary_list_file
ps -ax | grep "$chromehelper_name" | grep flash >> $temporary_list_file
while IFS=' ' read -r process_id tty _time path args; do
        # damn ;-)
        if [[ "$path" == "grep" ]]; then
            continue;
        fi
        echo " "
        rm -f $previous_cpulimit_pid_file
        ps -ax | grep 'cpulimit' | grep "pid=$process_id" > $previous_cpulimit_pid_file
        while IFS=' ' read -r previous_cpulimit_pid dummy dummy; do
            if [[ ! -z $previous_cpulimit_pid ]]; then
                echo -n "- Cancel previous cpulimit process($previous_cpulimit_pid) ..."
                kill -TERM $previous_cpulimit_pid > /dev/null
                if [ $? -eq 0 ]; then
                    echo " ok"
                else
                    echo " failed. you should check out."
                fi
            fi
        done <"$previous_cpulimit_pid_file"

        $cmd --limit=$limit --pid=$process_id -z  2>&1 > /dev/null &
        echo "=> Set cpu usage limitation '${limit}%' to the process($path)"
done <"$temporary_list_file"

clean_up