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//
// Copyright (C) 2014 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef UPDATE_ENGINE_UPDATE_MANAGER_DEFAULT_POLICY_H_
#define UPDATE_ENGINE_UPDATE_MANAGER_DEFAULT_POLICY_H_
#include <memory>
#include <string>
#include <base/time/time.h>
#include "update_engine/update_manager/policy.h"
namespace chromeos_update_manager {
// Auxiliary state class for DefaultPolicy evaluations.
//
// IMPORTANT: The use of a state object in policies is generally forbidden, as
// it was a design decision to keep policy calls side-effect free. We make an
// exception here to ensure that DefaultPolicy indeed serves as a safe (and
// secure) fallback option. This practice should be avoided when imlpementing
// other policies.
class DefaultPolicyState {
public:
DefaultPolicyState() {}
bool IsLastCheckAllowedTimeSet() const {
return last_check_allowed_time_ != base::Time::Max();
}
// Sets/returns the point time on the monotonic time scale when the latest
// check allowed was recorded.
void set_last_check_allowed_time(base::Time timestamp) {
last_check_allowed_time_ = timestamp;
}
base::Time last_check_allowed_time() const {
return last_check_allowed_time_;
}
private:
base::Time last_check_allowed_time_ = base::Time::Max();
};
// The DefaultPolicy is a safe Policy implementation that doesn't fail. The
// values returned by this policy are safe default in case of failure of the
// actual policy being used by the UpdateManager.
class DefaultPolicy : public Policy {
public:
DefaultPolicy() : aux_state_(new DefaultPolicyState()) {}
~DefaultPolicy() override = default;
// Policy overrides.
EvalStatus UpdateCheckAllowed(EvaluationContext* ec,
State* state,
std::string* error,
UpdateCheckParams* result) const override;
EvalStatus UpdateCanBeApplied(
EvaluationContext* ec,
State* state,
std::string* error,
chromeos_update_engine::ErrorCode* result,
chromeos_update_engine::InstallPlan* install_plan) const override;
EvalStatus UpdateCanStart(EvaluationContext* ec,
State* state,
std::string* error,
UpdateDownloadParams* result,
UpdateState update_state) const override;
EvalStatus P2PEnabled(EvaluationContext* ec,
State* state,
std::string* error,
bool* result) const override;
EvalStatus P2PEnabledChanged(EvaluationContext* ec,
State* state,
std::string* error,
bool* result,
bool prev_result) const override;
protected:
// Policy override.
std::string PolicyName() const override { return "DefaultPolicy"; }
private:
// An auxiliary state object.
std::unique_ptr<DefaultPolicyState> aux_state_;
DISALLOW_COPY_AND_ASSIGN(DefaultPolicy);
};
} // namespace chromeos_update_manager
#endif // UPDATE_ENGINE_UPDATE_MANAGER_DEFAULT_POLICY_H_