manifest_api.py 文件源码

def kill_dnsmasq(config):
    # There can be more than one bound to it, especially if libvirt was used..
    # Easy way: started from (previous) run of manifest_api.
    if config['PXE_INTERFACE'] is None:
        return
    try:
        with open(config['DNSMASQ_PIDFILE'], 'r') as f:
            pid = int(f.read())
        kill_pid(pid, 'dnsmasq')
    except Exception:   # a valiant effort in vain
        pass

    # Hard way: track down dnsmasq(s) attached to the configured interface.
    pxe_interface = config['PXE_INTERFACE']
    if pxe_interface not in NIF.interfaces():
        return
    tmp = NIF.ifaddresses(pxe_interface).get(NIF.AF_INET, None)
    if tmp is None:         # ASS-U-MES "torms" address bound here
        return
    pxe_addr = tmp[0]['addr']

    # libvirt bridge will always have DNS (53).  A truly simple net definition
    # won't have TFTP (69) but others might.  Obviously one started from here
    # will have TFTP.  And /etc/init.d/dnsmasq starts a *.* DNS listener
    # which picks up PXE_INTERFACE when explicitly bound processes are killed.
    # net_connections returns an object with a laddr field that's a tuple
    # of (listenaddress, port).   Filter on that.

    openconns = [(c.laddr[1], c.pid)    # port, pid
        for c in psutil.net_connections(kind='inet4')
            if c.laddr[1] in (53, 69) and (
                c.laddr[0] == pxe_addr or c.laddr[0] == '0.0.0.0'
            )]
    pids = set(c[1] for c in openconns)
    if pids:
        mainapp.logger.info('Killing %d copies of dnsmasq' % len(pids))
    while len(pids):
        pid = pids.pop()
        kill_pid(pid, 'dnsmasq')    # Until someone starts using bind9...