/* * * Copyright (c) 2021 Project CHIP Authors * * 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. */ /** * @file * This file defines and implements some utlities for generating persistent storage keys * */ #pragma once #include namespace chip { // This macro generates a key for storage using a node ID and a key prefix, and performs the given action // on that key. #define PERSISTENT_KEY_OP(node, keyPrefix, key, action) \ do \ { \ constexpr size_t len = std::extent::value; \ static_assert(len > 0, "keyPrefix length must be known at compile time"); \ /* 2 * sizeof(chip::NodeId) to accommodate 2 character for each byte in Node Id */ \ char key[len + 2 * sizeof(chip::NodeId) + 1]; \ static_assert(sizeof(node) <= sizeof(uint64_t), "Node ID size is greater than expected"); \ /* Be careful about switching to ChipLogFormatX64: it would change the storage keys! */ \ snprintf(key, sizeof(key), "%s%" PRIx64, keyPrefix, node); \ action; \ } while (0) } // namespace chip