1 // Copyright (C) 2019 Google LLC 2 // 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 #ifndef ICING_STORE_DOCUMENT_ID_H_ 16 #define ICING_STORE_DOCUMENT_ID_H_ 17 18 #include <cstdint> 19 20 namespace icing { 21 namespace lib { 22 23 // Id of a document 24 using DocumentId = int32_t; 25 26 // We use 22 bits to encode document_ids and use the largest value (2^22 - 1) to 27 // represent an invalid document_id. 28 inline constexpr int kDocumentIdBits = 22; 29 inline constexpr DocumentId kInvalidDocumentId = 30 (INT32_C(1) << kDocumentIdBits) - 1; 31 inline constexpr DocumentId kMinDocumentId = 0; 32 inline constexpr DocumentId kMaxDocumentId = kInvalidDocumentId - 1; 33 IsDocumentIdValid(DocumentId document_id)34constexpr bool IsDocumentIdValid(DocumentId document_id) { 35 return document_id >= kMinDocumentId && document_id <= kMaxDocumentId; 36 } 37 38 } // namespace lib 39 } // namespace icing 40 41 #endif // ICING_STORE_DOCUMENT_ID_H_ 42