os-win/os_win/utils/compute/_clusapi_utils.py

198 lines
7.5 KiB
Python

# Copyright 2016 Cloudbase Solutions Srl
# All Rights Reserved.
#
# 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 ctypes
import sys
if sys.platform == 'win32':
clusapi = ctypes.windll.clusapi
from os_win import constants
from os_win import exceptions
from os_win.utils import win32utils
DWORD = ctypes.c_ulong
CLUSPROP_SYNTAX_NAME = 262147
CLUSPROP_SYNTAX_ENDMARK = 0
CLUSPROP_SYNTAX_LIST_VALUE_DWORD = 65538
CLUSAPI_GROUP_MOVE_RETURN_TO_SOURCE_NODE_ON_ERROR = 2
CLUSAPI_GROUP_MOVE_QUEUE_ENABLED = 4
CLUSAPI_GROUP_MOVE_HIGH_PRIORITY_START = 8
ERROR_IO_PENDING = 997
CLUSPROP_NAME_VM = 'Virtual Machine'
CLUSPROP_NAME_VM_CONFIG = 'Virtual Machine Configuration'
class ClusApiUtils(object):
_MAX_NODE_NAME = 255
_open_handle_check_flags = dict(ret_val_is_err_code=False,
error_on_nonzero_ret_val=False,
error_ret_vals=[0, None])
def __init__(self):
self._win32utils = win32utils.Win32Utils()
def _run_and_check_output(self, *args, **kwargs):
kwargs['failure_exc'] = exceptions.ClusterWin32Exception
return self._win32utils.run_and_check_output(*args, **kwargs)
def _dword_align(self, value):
return (value + 3) & ~3
def _get_clusprop_value_struct(self, val_type):
def _get_padding():
# The cluster property entries must be 4B aligned.
val_sz = ctypes.sizeof(val_type)
return self._dword_align(val_sz) - val_sz
# For convenience, as opposed to the homonymous ClusAPI
# structure, we add the actual value as well.
class CLUSPROP_VALUE(ctypes.Structure):
_fields_ = [('syntax', DWORD),
('length', DWORD),
('value', val_type),
('_padding', ctypes.c_ubyte * _get_padding())]
return CLUSPROP_VALUE
def get_property_list_entry(self, name, syntax, value):
# The value argument must have a ctypes type.
name_len = len(name) + 1
val_sz = ctypes.sizeof(value)
class CLUSPROP_LIST_ENTRY(ctypes.Structure):
_fields_ = [
('name', self._get_clusprop_value_struct(
val_type=ctypes.c_wchar * name_len)),
('value', self._get_clusprop_value_struct(
val_type=ctypes.c_ubyte * val_sz)),
('_endmark', DWORD)
]
entry = CLUSPROP_LIST_ENTRY()
entry.name.syntax = CLUSPROP_SYNTAX_NAME
entry.name.length = name_len * ctypes.sizeof(ctypes.c_wchar)
entry.name.value = name
entry.value.syntax = syntax
entry.value.length = val_sz
entry.value.value[0:val_sz] = bytearray(value)
entry._endmark = CLUSPROP_SYNTAX_ENDMARK
return entry
def get_property_list(self, property_entries):
prop_entries_sz = sum([ctypes.sizeof(entry)
for entry in property_entries])
class CLUSPROP_LIST(ctypes.Structure):
_fields_ = [('count', DWORD),
('entries_buff', ctypes.c_ubyte * prop_entries_sz)]
prop_list = CLUSPROP_LIST(count=len(property_entries))
pos = 0
for prop_entry in property_entries:
prop_entry_sz = ctypes.sizeof(prop_entry)
prop_list.entries_buff[pos:prop_entry_sz + pos] = bytearray(
prop_entry)
pos += prop_entry_sz
return prop_list
def open_cluster(self, cluster_name=None):
"""Returns a handle for the requested cluster.
:param cluster_name: (Optional) specifies the name of the cluster
to be opened. If None, the cluster that the
local node belongs to will be opened.
"""
p_clus_name = ctypes.c_wchar_p(cluster_name) if cluster_name else None
handle = self._run_and_check_output(clusapi.OpenCluster,
p_clus_name,
**self._open_handle_check_flags)
return handle
def open_cluster_group(self, cluster_handle, group_name):
handle = self._run_and_check_output(clusapi.OpenClusterGroup,
cluster_handle,
ctypes.c_wchar_p(group_name),
**self._open_handle_check_flags)
return handle
def open_cluster_node(self, cluster_handle, node_name):
handle = self._run_and_check_output(clusapi.OpenClusterNode,
cluster_handle,
ctypes.c_wchar_p(node_name),
**self._open_handle_check_flags)
return handle
def close_cluster(self, cluster_handle):
# This function will always return 'True'. Closing the cluster
# handle will also invalidate handles opened using it.
clusapi.CloseCluster(cluster_handle)
def close_cluster_group(self, group_handle):
# TODO(lpetrut): The following functions can fail, in which case
# 'False' will be returned. We may want to handle this situation.
clusapi.CloseClusterGroup(group_handle)
def close_cluster_node(self, node_handle):
clusapi.CloseClusterNode(node_handle)
def cancel_cluster_group_operation(self, group_handle):
"""Requests a pending move operation to be canceled."""
# This only applies to move operations requested by
# MoveClusterGroup(Ex), thus it will not apply to fail overs.
self._run_and_check_output(
clusapi.CancelClusterGroupOperation,
group_handle,
0, # cancel flags (reserved for future use by MS)
ignored_error_codes=[ERROR_IO_PENDING])
def move_cluster_group(self, group_handle, destination_node_handle,
move_flags, property_list):
prop_list_p = ctypes.byref(property_list) if property_list else None
prop_list_sz = ctypes.sizeof(property_list) if property_list else 0
self._run_and_check_output(clusapi.MoveClusterGroupEx,
group_handle,
destination_node_handle,
move_flags,
prop_list_p,
prop_list_sz,
ignored_error_codes=[ERROR_IO_PENDING])
def get_cluster_group_state(self, group_handle):
node_name_len = DWORD(self._MAX_NODE_NAME)
node_name_buff = (ctypes.c_wchar * node_name_len.value)()
group_state = self._run_and_check_output(
clusapi.GetClusterGroupState,
group_handle,
ctypes.byref(node_name_buff),
ctypes.byref(node_name_len),
error_ret_vals=[constants.CLUSTER_GROUP_STATE_UNKNOWN],
error_on_nonzero_ret_val=False,
ret_val_is_err_code=False)
return {'state': group_state,
'owner_node': node_name_buff.value}