git pre-push hook: do not allow push to master branch

pre-push

#!/bin/sh

# The remote repo
remote="$1"
url="$2"

# Check each commit that's being pushed
while read local_ref local_sha remote_ref remote_sha
do
  if [ "$remote_ref" = "refs/heads/master" ]; then
    echo "Error: You're attempting to push to the remote master branch. This is not allowed!"
    exit 1
  fi
done

save it as .git/hooks/pre-push and make the file executable