Auto launching ssh-agent on msysgit

msysgit_ssh_agent.sh

# Originally written by Github:
#  https://help.github.com/articles/working-with-ssh-key-passphrases

SSH_ENV="$HOME/.ssh/environment"

# start the ssh-agent
function start_agent {
    echo "Initializing new SSH agent..."
    # spawn ssh-agent
    ssh-agent | sed 's/^echo/#echo/' > "$SSH_ENV"
    echo succeeded
    chmod 600 "$SSH_ENV"
    . "$SSH_ENV" > /dev/null
    ssh-add
}

# test for identities
function test_identities {
    # test whether standard identities have been added to the agent already
    ssh-add -l | grep "The agent has no identities" > /dev/null
    if [ $? -eq 0 ]; then
        ssh-add
        # $SSH_AUTH_SOCK broken so we start a new proper agent
        if [ $? -eq 2 ];then
            start_agent
        fi
    fi
}

function load_ssh_agent {
    if [ -f "$SSH_ENV" ]; then
        . "$SSH_ENV" > /dev/null
    fi

    ps -ef | grep "$SSH_AGENT_PID" | grep ssh-agent > /dev/null
    if [ $? -eq 0 ]; then
        test_identities
    else
        start_agent
    fi
}

# check for running ssh-agent with proper $SSH_AGENT_PID
if [ -n "$SSH_AGENT_PID" ]; then
    ps -ef | grep "$SSH_AGENT_PID" | grep ssh-agent > /dev/null
    if [ $? -eq 0 ]; then
        test_identities
    else
        # either there is no process with that PID or it does not correspond 
        #  to ssh-agent
        echo "SSH_AGENT_PID is set to $SSH_AGENT_PID, but that process either"
        echo " does not exist, or is not ssh-agent"
        load_ssh_agent
    fi
# if $SSH_AGENT_PID is not properly set, we might be able to load one from
#  $SSH_ENV
else
    load_ssh_agent
fi