1 // 2 // Copyright (C) 2014 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 UPDATE_ENGINE_UPDATE_MANAGER_RANDOM_PROVIDER_H_ 18 #define UPDATE_ENGINE_UPDATE_MANAGER_RANDOM_PROVIDER_H_ 19 20 #include "update_engine/update_manager/provider.h" 21 #include "update_engine/update_manager/variable.h" 22 23 namespace chromeos_update_manager { 24 25 // Provider of random values. 26 class RandomProvider : public Provider { 27 public: 28 ~RandomProvider() override {} 29 30 // Return a random number every time it is requested. Note that values 31 // returned by the variables are cached by the EvaluationContext, so the 32 // returned value will be the same during the same policy request. If more 33 // random values are needed use a PRNG seeded with this value. 34 virtual Variable<uint64_t>* var_seed() = 0; 35 36 protected: 37 RandomProvider() {} 38 39 private: 40 DISALLOW_COPY_AND_ASSIGN(RandomProvider); 41 }; 42 43 } // namespace chromeos_update_manager 44 45 #endif // UPDATE_ENGINE_UPDATE_MANAGER_RANDOM_PROVIDER_H_ 46