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 #include <string> 18 19 #include <sys/types.h> 20 #include <sys/stat.h> 21 #include <fcntl.h> 22 #include <unistd.h> 23 24 #include <android-base/logging.h> 25 26 // File descriptor which is automatically closed when this object is destroyed. 27 // Cannot be copied, since that would cause double-closes. 28 class AutoCloseFD { 29 public: 30 AutoCloseFD(const char *path, int flags = O_RDONLY, int mode = 0): 31 fd{TEMP_FAILURE_RETRY(open(path, flags | O_CLOEXEC, mode))} {} 32 AutoCloseFD(const std::string &path, int flags = O_RDONLY, int mode = 0): 33 AutoCloseFD(path.c_str(), flags, mode) {} ~AutoCloseFD()34 ~AutoCloseFD() { 35 if (fd != -1) { 36 int preserve_errno = errno; 37 if (close(fd) == -1) { 38 PLOG(ERROR) << "close(2) failed"; 39 }; 40 errno = preserve_errno; 41 } 42 } 43 AutoCloseFD(const AutoCloseFD&) = delete; 44 AutoCloseFD& operator=(const AutoCloseFD&) = delete; 45 explicit operator bool() {return fd != -1;} get()46 int get() const {return fd;} 47 private: 48 const int fd; 49 }; 50 51