1 // Copyright (C) 2021 Google LLC 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #ifndef ICING_FILE_DESTRUCTIBLE_FILE_H_ 16 #define ICING_FILE_DESTRUCTIBLE_FILE_H_ 17 18 #include <unistd.h> 19 20 #include <string> 21 22 #include "icing/file/filesystem.h" 23 #include "icing/util/logging.h" 24 25 namespace icing { 26 namespace lib { 27 28 // A convenient RAII class which will open the specified file path for write and 29 // delete the underlying file upon destruction. 30 class DestructibleFile { 31 public: DestructibleFile(const std::string & filepath,const Filesystem * filesystem)32 explicit DestructibleFile(const std::string& filepath, 33 const Filesystem* filesystem) 34 : filesystem_(filesystem), filepath_(filepath) { 35 fd_ = filesystem_->OpenForWrite(filepath_.c_str()); 36 } 37 38 DestructibleFile(const DestructibleFile&) = delete; DestructibleFile(DestructibleFile && other)39 DestructibleFile(DestructibleFile&& other) : filesystem_(nullptr), fd_(-1) { 40 *this = std::move(other); 41 } 42 43 DestructibleFile& operator=(const DestructibleFile&) = delete; 44 DestructibleFile& operator=(DestructibleFile&& other) { 45 std::swap(fd_, other.fd_); 46 std::swap(filesystem_, other.filesystem_); 47 std::swap(filepath_, other.filepath_); 48 return *this; 49 } 50 ~DestructibleFile()51 ~DestructibleFile() { 52 if (is_valid()) { 53 close(fd_); 54 if (!filesystem_->DeleteFile(filepath_.c_str())) { 55 ICING_VLOG(1) << "Failed to delete file " << filepath_; 56 } 57 } 58 } 59 is_valid()60 bool is_valid() const { return fd_ >= 0; } get_fd()61 int get_fd() const { return fd_; } 62 63 private: 64 const Filesystem* filesystem_; 65 std::string filepath_; 66 int fd_; 67 }; 68 69 } // namespace lib 70 } // namespace icing 71 72 #endif // ICING_FILE_DESTRUCTIBLE_FILE_H_ 73