1 // Copyright (C) 2018 The Android Open Source Project 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 IORAP_SRC_INODE2FILENAME_INODE_H_ 16 #define IORAP_SRC_INODE2FILENAME_INODE_H_ 17 18 #include <functional> 19 #include <ostream> 20 #include <string> 21 22 #include <stddef.h> 23 24 namespace iorap::inode2filename { 25 26 struct Inode { 27 size_t device_major; // dev_t = makedev(major, minor) 28 size_t device_minor; 29 size_t inode; // ino_t = inode 30 31 static bool Parse(const std::string& str, /*out*/Inode* out, /*out*/std::string* error_msg); 32 33 bool operator==(const Inode& rhs) const { 34 return device_major == rhs.device_major && 35 device_minor == rhs.device_minor && 36 inode == rhs.inode; 37 } 38 39 bool operator!=(const Inode& rhs) const { 40 return !(*this == rhs); 41 } 42 }; 43 44 inline std::ostream& operator<<(std::ostream& os, const Inode& inode) { 45 os << inode.device_major << ":" << inode.device_minor << ":" << inode.inode; 46 return os; 47 } 48 49 } // namespace iorap::inode2filename 50 51 namespace std { 52 template <> 53 struct hash<iorap::inode2filename::Inode> { 54 using argument_type = iorap::inode2filename::Inode; 55 using result_type = size_t; 56 result_type operator()(argument_type const& s) const noexcept { 57 // Hash the inode by using only the inode#. Ignore devices, we are extremely unlikely 58 // to ever collide on the devices. 59 result_type const h1 = std::hash<size_t>{}(s.inode); 60 return h1; 61 } 62 }; 63 } // namespace std 64 65 #endif // IORAP_SRC_INODE2FILENAME_INODE_H_ 66