VintfObjectUtils.h

/*
 * Copyright (C) 2021 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.
 */

// Special utils for VintfObject(s).

#pragma once

// This is okay because it is a header private to libvintf. Do not do this in exported headers!
#include <android-base/logging.h>

#include <vintf/VintfObject.h>

namespace android {
namespace vintf {
namespace details {

template <typename T, typename F>
std::shared_ptr<const T> Get(const char* id, LockedSharedPtr<T>* ptr,
                             const F& fetchAllInformation) {
    std::unique_lock<std::mutex> _lock(ptr->mutex);
    if (!ptr->fetchedOnce) {
        LOG(INFO) << id << ": Reading VINTF information.";
        ptr->object = std::make_unique<T>();
        std::string error;
        status_t status = fetchAllInformation(ptr->object.get(), &error);
        if (status == OK) {
            ptr->fetchedOnce = true;
            LOG(INFO) << id << ": Successfully processed VINTF information";
        } else {
            // Doubled because a malformed error std::string might cause us to
            // lose the status.
            LOG(ERROR) << id << ": status from fetching VINTF information: " << status;
            LOG(ERROR) << id << ": " << status << " VINTF parse error: " << error;
            ptr->object = nullptr;  // frees the old object
        }
    }
    return ptr->object;
}

}  // namespace details
}  // namespace vintf
}  // namespace android