GnuPG/SSH agent setup for inclusion in bashrc on MacOS

do_gpg_setup.bash

do_gpg_setup() {
	local ssh_add_err

        if gpg-connect-agent /bye &>/dev/null && [[ -e "$HOME/.ssh_auth_sock" ]] && { ssh_add_err=$(SSH_AUTH_SOCK=$HOME/.ssh_auth_sock ssh-add -l 2>&1) || [[ $ssh_add_err = "The agent has no identities." ]]; }; then
                export SSH_AUTH_SOCK=$HOME/.ssh_auth_sock
                return # Nothing to do
        else
                [[ $orig_GPG_AGENT_INFO ]] && GPG_AGENT_INFO=$orig_GPG_AGENT_INFO gpg-connect-agent killagent /bye
                [[ $GPG_AGENT_INFO ]] && GPG_AGENT_INFO=$GPG_AGENT_INFO gpg-connect-agent killagent /bye
        fi

        local cmds
        cmds="$(gpg-agent --daemon --enable-ssh-support)" || return
        eval "$cmds"

	if [[ $SSH_AUTH_SOCK ]]; then
		export ssh_agent_is_gpg_agent=1
		orig_SSH_AUTH_SOCK=$SSH_AUTH_SOCK
		ln -s -f -- "$orig_SSH_AUTH_SOCK" $HOME/.ssh_auth_sock
		SSH_AUTH_SOCK=$HOME/.ssh_auth_sock
		export orig_SSH_AUTH_SOCK
	fi

	if [[ $GPG_AGENT_INFO ]]; then
		: "${orig_GPG_AGENT_INFO:=$GPG_AGENT_INFO}"
		IFS=: read -r gpg_agent_file gpg_agent_pid _ <<<"$GPG_AGENT_INFO"
		ln -s -f -- "$gpg_agent_file" "$HOME/.gpg_agent_lock"
		GPG_AGENT_INFO="$HOME/.gpg_agent_lock:${GPG_AGENT_INFO#*:}"
		export orig_GPG_AGENT_INFO
	fi
}
do_gpg_setup