| /** @file |
| |
| Generic "guard" class templates. The destructor calls a function object with arbitrary parameters. This utility is |
| available in both the core and plugins. |
| |
| @section license License |
| |
| Licensed to the Apache Software Foundation (ASF) under one |
| or more contributor license agreements. See the NOTICE file |
| distributed with this work for additional information |
| regarding copyright ownership. The ASF licenses this file |
| to you 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. |
| */ |
| |
| #pragma once |
| |
| namespace ts |
| { |
| // The destructor of this class calls the function object passed to its constructor. The function object must support a |
| // function call operator with no parameters. For example: |
| // |
| // ts::PostScript g([=]() -> void { TSHandleMLocRelease(bufp, parent, hdr); }); |
| // |
| // The release() member will prevent the call to the function upon destruction. |
| // |
| // Helpful in avoiding errors due to exception throws or error function return points (like the one that caused Heartbleed). |
| // |
| template <typename Callable> class PostScript |
| { |
| public: |
| PostScript(Callable f) : _f(f) {} |
| |
| ~PostScript() |
| { |
| if (_armed) { |
| _f(); |
| } |
| } |
| |
| void |
| release() |
| { |
| _armed = false; |
| } |
| |
| // No copying or moving. |
| PostScript(const PostScript &) = delete; |
| PostScript &operator=(const PostScript &) = delete; |
| |
| private: |
| bool _armed = true; |
| Callable _f; |
| }; |
| |
| } // end namespace ts |