1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef ANDROID_AUTO_FD_H_ 18 #define ANDROID_AUTO_FD_H_ 19 20 #include <unistd.h> 21 22 namespace android { 23 24 class UniqueFd { 25 public: 26 UniqueFd() = default; UniqueFd(int fd)27 UniqueFd(int fd) : fd_(fd) { 28 } UniqueFd(UniqueFd && rhs)29 UniqueFd(UniqueFd &&rhs) { 30 fd_ = rhs.fd_; 31 rhs.fd_ = -1; 32 } 33 34 UniqueFd &operator=(UniqueFd &&rhs) { 35 Set(rhs.Release()); 36 return *this; 37 } 38 ~UniqueFd()39 ~UniqueFd() { 40 if (fd_ >= 0) 41 close(fd_); 42 } 43 Release()44 int Release() { 45 int old_fd = fd_; 46 fd_ = -1; 47 return old_fd; 48 } 49 Set(int fd)50 int Set(int fd) { 51 if (fd_ >= 0) 52 close(fd_); 53 fd_ = fd; 54 return fd_; 55 } 56 Close()57 void Close() { 58 if (fd_ >= 0) 59 close(fd_); 60 fd_ = -1; 61 } 62 get()63 int get() const { 64 return fd_; 65 } 66 67 private: 68 int fd_ = -1; 69 }; 70 71 struct OutputFd { 72 OutputFd() = default; OutputFdOutputFd73 OutputFd(int *fd) : fd_(fd) { 74 } OutputFdOutputFd75 OutputFd(OutputFd &&rhs) { 76 fd_ = rhs.fd_; 77 rhs.fd_ = NULL; 78 } 79 80 OutputFd &operator=(OutputFd &&rhs) { 81 fd_ = rhs.fd_; 82 rhs.fd_ = NULL; 83 return *this; 84 } 85 SetOutputFd86 int Set(int fd) { 87 if (*fd_ >= 0) 88 close(*fd_); 89 *fd_ = fd; 90 return fd; 91 } 92 getOutputFd93 int get() { 94 return *fd_; 95 } 96 97 operator bool() const { 98 return fd_ != NULL; 99 } 100 101 private: 102 int *fd_ = NULL; 103 }; 104 } 105 106 #endif 107