def _init_mailslot(cls, id):
if cls.mm is None:
# First time has some extra setup, not all vars need to be kept.
buf = os.fstat(cls.fd)
assert STAT.S_ISREG(buf.st_mode), 'Mailbox FD is not a regular file'
cls.mm = mmap.mmap(cls.fd, 0)
view = memoryview(cls.mm)
mbg = IVSHMSG_MailGlobals.from_buffer(view)
# Convenience
cls.nClients = mbg.nClients
cls.nEvents = mbg.nEvents
cls.server_id = mbg.server_id
# Create all the peer data structures now as it simplifies
# connection logic removes interplay from twisted_client.py.
cls.slots = [ None, ] * cls.nEvents
cls.slots[0] = mbg
for slot in range(1, cls.nEvents):
cls.slots[slot] = IVSHMSG_MailSlot.from_buffer(
view[mbg.slotsize * slot : mbg.slotsize * (slot + 1)])
assert cls.slots[slot].peer_id == slot, 'What happened?'
if id > cls.server_id: # Probably a test run of twisted_restapi
return
assert cls.slots[id].peer_id == id, 'What happened?'
cls.clear_mailslot(id)
def __init__(self, args=None, fd=-1, client_id=-1, nodename=None):
'''Server: args with command line stuff from command line.
Client: starts with an fd and id read from AF_UNIX socket.'''
if self._beentheredonethat:
return
self.__class__._beetnheredonethat = True
assert (self.MS_MSG_off +
self.MS_MAX_MSGLEN == self.MAILBOX_SLOTSIZE), 'Fix this NOW'
self.filesize = self.MAILBOX_MAX_SLOTS * self.MAILBOX_SLOTSIZE
if args is None:
assert fd > 0 and client_id > 0 and isinstance(nodename, str), \
'Bad call, ump!'
self.__class__.fd = fd
self.nodename = nodename
self._init_mailslot(client_id, nodename)
return
assert fd == -1 and client_id == -1, 'Cannot assign ids to server'
path = args.mailbox # Match previously written code
gr_gid = -1 # Makes no change. Try Debian, CentOS, other
for gr_name in ('libvirt-qemu', 'libvirt', 'libvirtd'):
try:
gr_gid = grp.getgrnam(gr_name).gr_gid
break
except Exception as e:
pass
if '/' not in path:
path = '/dev/shm/' + path
oldumask = os.umask(0)
try:
if not os.path.isfile(path):
fd = os.open(path, os.O_RDWR | os.O_CREAT, mode=0o666)
os.posix_fallocate(fd, 0, self.filesize)
os.fchown(fd, -1, gr_gid)
else: # Re-condition and re-use
lstat = os.lstat(path)
assert STAT.S_ISREG(lstat.st_mode), 'not a regular file'
assert lstat.st_size >= self.filesize, \
'existing size (%d) is < required (%d)' % (
lstat.st_size, self.filesize)
if lstat.st_gid != gr_gid and gr_gid > 0:
print('Changing %s to group %s' % (path, gr_name))
os.chown(path, -1, gr_gid)
if lstat.st_mode & 0o660 != 0o660: # at least
print('Changing %s to permissions 666' % path)
os.chmod(path, 0o666)
fd = os.open(path, os.O_RDWR)
except Exception as e:
raise RuntimeError('Problem with %s: %s' % (path, str(e)))
os.umask(oldumask)
self.path = path # Final absolute path
self.__class__.fd = fd
self._initialize_mailbox(args)
def ftype(self):
st = lstat(self._path)
if statc.S_ISLNK(st.st_mode):
return LINK
elif statc.S_ISREG(st.st_mode):
return FILE
elif statc.S_ISDIR(st.st_mode):
return DIR
else:
raise ValueError("%s is not in %s" % (self, TYPES))
def _init_mailslot(cls, id, nodename):
buf = os.fstat(cls.fd)
assert STAT.S_ISREG(buf.st_mode), 'Mailbox FD is not a regular file'
if cls.mm is None:
cls.mm = mmap.mmap(cls.fd, 0)
(cls.nClients, cls.nEvents, cls.server_id) = struct.unpack(
'QQQ', cls.mm[cls.G_NCLIENTS_off:cls.G_NCLIENTS_off + 24])
# mailbox slot starts with nodename
cls.clear_mailslot(id, nodenamebytes=nodename.encode())