1 /* 2 * Copyright (c) 2025 Huawei Device Co., Ltd. 3 * Licensed under the Apache License, Version 2.0 (the "License"); 4 * you may not use this file except in compliance with the License. 5 * You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software 10 * distributed under the License is distributed on an "AS IS" BASIS, 11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 * See the License for the specific language governing permissions and 13 * limitations under the License. 14 */ 15 16 #ifndef COMMON_COMPONENTS_BASE_HASH_UTILS_H 17 #define COMMON_COMPONENTS_BASE_HASH_UTILS_H 18 19 #include <cstdint> 20 21 #include "common_components/base/c_string.h" 22 23 namespace common { 24 25 struct HashString { 26 // 211 is a proper prime, which can reduce the conflict rate. 27 const uint32_t properPrime = 211; 28 operatorHashString29 size_t operator()(const char* key) const 30 { 31 uint32_t hash = 0; 32 while ((*key) != '\0') { 33 uint32_t keyChar = *key; 34 hash = hash * properPrime + keyChar; 35 key += 1; 36 } 37 return hash; 38 } 39 }; 40 struct EqualString { operatorEqualString41 bool operator()(const char* lhs, const char* rhs) const { return strcmp(lhs, rhs) == 0; } 42 }; 43 44 } // namespace common 45 46 #endif // COMMON_COMPONENTS_BASE_HASH_UTILS_H 47