| # |
| # Copyright 2015 ClusterHQ |
| # |
| # 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. |
| # |
| |
| """ |
| The package that contains a module per each C library that |
| `libzfs_core` uses. The modules expose CFFI objects required |
| to make calls to functions in the libraries. |
| """ |
| from __future__ import absolute_import, division, print_function |
| |
| import threading |
| import importlib |
| |
| from cffi import FFI |
| |
| |
| def _setup_cffi(): |
| class LazyLibrary(object): |
| |
| def __init__(self, ffi, libname): |
| self._ffi = ffi |
| self._libname = libname |
| self._lib = None |
| self._lock = threading.Lock() |
| |
| def __getattr__(self, name): |
| if self._lib is None: |
| with self._lock: |
| if self._lib is None: |
| self._lib = self._ffi.dlopen(self._libname) |
| |
| return getattr(self._lib, name) |
| |
| MODULES = ["libnvpair", "libzfs_core"] |
| ffi = FFI() |
| |
| for module_name in MODULES: |
| module = importlib.import_module("." + module_name, __name__) |
| ffi.cdef(module.CDEF) |
| lib = LazyLibrary(ffi, module.LIBRARY) |
| setattr(module, "ffi", ffi) |
| setattr(module, "lib", lib) |
| |
| |
| _setup_cffi() |
| |
| # vim: softtabstop=4 tabstop=4 expandtab shiftwidth=4 |