deb-ryu/ryu/contrib/ovs/unixctl/__init__.py

84 lines
2.8 KiB
Python

# Copyright (c) 2011, 2012 Nicira, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import types
import ovs.util
commands = {}
strtypes = types.StringTypes
class _UnixctlCommand(object):
def __init__(self, usage, min_args, max_args, callback, aux):
self.usage = usage
self.min_args = min_args
self.max_args = max_args
self.callback = callback
self.aux = aux
def _unixctl_help(conn, unused_argv, unused_aux):
reply = "The available commands are:\n"
command_names = sorted(commands.keys())
for name in command_names:
reply += " "
usage = commands[name].usage
if usage:
reply += "%-23s %s" % (name, usage)
else:
reply += name
reply += "\n"
conn.reply(reply)
def command_register(name, usage, min_args, max_args, callback, aux):
""" Registers a command with the given 'name' to be exposed by the
UnixctlServer. 'usage' describes the arguments to the command; it is used
only for presentation to the user in "help" output.
'callback' is called when the command is received. It is passed a
UnixctlConnection object, the list of arguments as unicode strings, and
'aux'. Normally 'callback' should reply by calling
UnixctlConnection.reply() or UnixctlConnection.reply_error() before it
returns, but if the command cannot be handled immediately, then it can
defer the reply until later. A given connection can only process a single
request at a time, so a reply must be made eventually to avoid blocking
that connection."""
assert isinstance(name, strtypes)
assert isinstance(usage, strtypes)
assert isinstance(min_args, int)
assert isinstance(max_args, int)
assert isinstance(callback, types.FunctionType)
if name not in commands:
commands[name] = _UnixctlCommand(usage, min_args, max_args, callback,
aux)
def socket_name_from_target(target):
assert isinstance(target, strtypes)
if target.startswith("/"):
return 0, target
pidfile_name = "%s/%s.pid" % (ovs.dirs.RUNDIR, target)
pid = ovs.daemon.read_pidfile(pidfile_name)
if pid < 0:
return -pid, "cannot read pidfile \"%s\"" % pidfile_name
return 0, "%s/%s.%d.ctl" % (ovs.dirs.RUNDIR, target, pid)
command_register("help", "", 0, 0, _unixctl_help, None)