This is an example of a GIT "post-receive" hook that check the branch name before deploying

post-receive

#!/bin/bash
while read oldrev newrev refname
do
    branch=$(git rev-parse --symbolic --abbrev-ref $refname)
    if [ "master" == "$branch" ]; then
		git --work-tree=/var/www/domain.com --git-dir=/home/git/repositories/root/testproject.git checkout -f
    fi
done