1 // 2 // Copyright (C) 2015 Google, Inc. 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 #pragma once 18 19 #include <array> 20 #include <string> 21 22 // TODO: Find places that break include what you use and remove this. 23 #include <base/logging.h> 24 #include <hardware/bluetooth.h> 25 26 namespace bluetooth { 27 28 class UUID { 29 public: 30 static constexpr size_t kNumBytes128 = 16; 31 static constexpr size_t kNumBytes32 = 4; 32 static constexpr size_t kNumBytes16 = 2; 33 34 typedef std::array<uint8_t, kNumBytes16> UUID16Bit; 35 typedef std::array<uint8_t, kNumBytes32> UUID32Bit; 36 typedef std::array<uint8_t, kNumBytes128> UUID128Bit; 37 38 // Creates and returns a random 128-bit UUID. 39 static UUID GetRandom(); 40 41 // Creates and returns a UUID in which all 128 bits are equal to 0. 42 static UUID GetNil(); 43 44 // Creates and returns a UUID in which all 128 bits are equal to 1. 45 static UUID GetMax(); 46 47 // Construct a Bluetooth 'base' UUID. 48 UUID(); 49 virtual ~UUID() = default; 50 51 // BlueDroid constructor. 52 explicit UUID(const bt_uuid_t& uuid); 53 54 // String constructor. Only hex ASCII accepted. 55 explicit UUID(std::string uuid); 56 57 // std::array variants constructors. 58 explicit UUID(const UUID16Bit& uuid); 59 explicit UUID(const UUID32Bit& uuid); 60 explicit UUID(const UUID128Bit& uuid); 61 62 // Provide the full network-byte-ordered blob. 63 UUID128Bit GetFullBigEndian() const; 64 65 // Provide blob in Little endian (BlueDroid expects this). 66 UUID128Bit GetFullLittleEndian() const; 67 68 // Helper for bluedroid LE type. 69 bt_uuid_t GetBlueDroid() const; 70 71 // Returns a string representation for the UUID. 72 std::string ToString() const; 73 74 // Returns whether or not this UUID was initialized correctly. 75 bool is_valid() const { return is_valid_; } 76 77 // Returns the shortest possible representation of this UUID in bytes. 78 size_t GetShortestRepresentationSize() const; 79 80 bool operator<(const UUID& rhs) const; 81 bool operator==(const UUID& rhs) const; 82 inline bool operator!=(const UUID& rhs) const { return !(*this == rhs); } 83 84 protected: 85 void InitializeDefault(); 86 87 // Network-byte-ordered ID. 88 UUID128Bit id_; 89 90 // True if this UUID was initialized with a correct representation. 91 bool is_valid_; 92 }; 93 94 } // namespace bluetooth 95 96 // Custom std::hash specialization so that bluetooth::UUID can be used as a key 97 // in std::unordered_map. 98 namespace std { 99 100 template <> 101 struct hash<bluetooth::UUID> { 102 std::size_t operator()(const bluetooth::UUID& key) const { 103 const auto& uuid_bytes = key.GetFullBigEndian(); 104 std::hash<std::string> hash_fn; 105 return hash_fn(std::string((char*)uuid_bytes.data(), uuid_bytes.size())); 106 } 107 }; 108 109 } // namespace std 110