| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * 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. |
| */ |
| |
| #ifndef ANDROID_BASE_UNIQUE_FD_H |
| #define ANDROID_BASE_UNIQUE_FD_H |
| |
| #include <unistd.h> |
| |
| #include <android-base/macros.h> |
| |
| /* Container for a file descriptor that automatically closes the descriptor as |
| * it goes out of scope. |
| * |
| * unique_fd ufd(open("/some/path", "r")); |
| * |
| * if (ufd.get() < 0) // invalid descriptor |
| * return error; |
| * |
| * // Do something useful |
| * |
| * return 0; // descriptor is closed here |
| */ |
| namespace android { |
| namespace base { |
| |
| class unique_fd final { |
| public: |
| unique_fd() : value_(-1) {} |
| |
| explicit unique_fd(int value) : value_(value) {} |
| ~unique_fd() { clear(); } |
| |
| unique_fd(unique_fd&& other) : value_(other.release()) {} |
| unique_fd& operator = (unique_fd&& s) { |
| reset(s.release()); |
| return *this; |
| } |
| |
| void reset(int new_value) { |
| if (value_ >= 0) |
| close(value_); |
| value_ = new_value; |
| } |
| |
| void clear() { |
| reset(-1); |
| } |
| |
| int get() const { return value_; } |
| |
| int release() { |
| int ret = value_; |
| value_ = -1; |
| return ret; |
| } |
| |
| private: |
| int value_; |
| |
| DISALLOW_COPY_AND_ASSIGN(unique_fd); |
| }; |
| |
| } // namespace base |
| } // namespace android |
| |
| #endif // ANDROID_BASE_UNIQUE_FD_H |