Runs snort against the supplied pcap.

        :param pcap: Filepath to pcap file to scan
        :returns: tuple of version, list of alerts

def run(self, pcap):
        """
        Runs snort against the supplied pcap.

        :param pcap: Filepath to pcap file to scan
        :returns: tuple of version, list of alerts
        """
        proc = Popen(self._snort_cmd(pcap), stdout=PIPE,
                     stderr=PIPE, universal_newlines=True)
        stdout, stderr = proc.communicate()
        if proc.returncode != 0:
            raise Exception("\n".join(["Execution failed return code: {0}" \
                                .format(proc.returncode), stderr or ""]))

        return (parse_version(stderr),
                [ x for x in parse_alert(stdout) ])