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 #include "icing/index/main/posting-list-utils.h" 16 17 #include "icing/legacy/index/icing-bit-util.h" 18 #include "icing/util/logging.h" 19 20 namespace icing { 21 namespace lib { 22 23 namespace posting_list_utils { 24 IsValidPostingListSize(uint32_t size_in_bytes)25bool IsValidPostingListSize(uint32_t size_in_bytes) { 26 // size must be sizeof(Hit) aligned. Otherwise, we can have serious 27 // wasted space in the worst case. 28 if (size_in_bytes % sizeof(Hit) != 0) { 29 ICING_LOG(ERROR) << "Size " << size_in_bytes << " hit " << sizeof(Hit); 30 return false; 31 } 32 33 // Must be able to store the min information. 34 if (size_in_bytes < min_posting_list_size()) { 35 ICING_LOG(ERROR) << "Size " << size_in_bytes << " is less than min size " 36 << min_posting_list_size(); 37 return false; 38 } 39 40 // We re-use the first two hits as pointers into the posting list 41 // so the posting list size must fit in sizeof(Hit). 42 if (BitsToStore(size_in_bytes) > sizeof(Hit::Value) * 8) { 43 ICING_LOG(ERROR) 44 << "Posting list size must be small enough to store the offset in " 45 << sizeof(Hit::Value) * 8 << " bytes."; 46 return false; 47 } 48 49 return true; 50 } 51 52 } // namespace posting_list_utils 53 54 } // namespace lib 55 } // namespace icing 56