Disallow force pushing to master

gistfile1.txt

#!/bin/bash

# this file is ./git/hooks/pre-push

protected_branch='master'  
current_branch=$(git symbolic-ref HEAD | sed -e 's,.*/\(.*\),\1,')
if [ $protected_branch = $current_branch ]  
then
  echo "y u do this? (You can not push to master)"
  exit 1;
fi