1 /* 2 * Copyright (C) 2017 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 NETUTILS_FD_H 18 #define NETUTILS_FD_H 19 20 #include <ostream> 21 22 #include "netdutils/Status.h" 23 24 namespace android { 25 namespace netdutils { 26 27 // Strongly typed wrapper for file descriptors with value semantics. 28 // This class should typically hold unowned file descriptors. 29 class Fd { 30 public: 31 constexpr Fd() = default; 32 Fd(int fd)33 constexpr Fd(int fd) : mFd(fd) {} 34 get()35 int get() const { return mFd; } 36 37 bool operator==(const Fd& other) const { return get() == other.get(); } 38 bool operator!=(const Fd& other) const { return get() != other.get(); } 39 40 private: 41 int mFd = -1; 42 }; 43 44 // Return true if fd appears valid (non-negative) isWellFormed(const Fd fd)45inline bool isWellFormed(const Fd fd) { 46 return fd.get() >= 0; 47 } 48 49 std::ostream& operator<<(std::ostream& os, const Fd& fd); 50 51 } // namespace netdutils 52 } // namespace android 53 54 #endif /* NETUTILS_FD_H */ 55