1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "util/strings/utf8.h" 18 19 namespace libtextclassifier2 { IsValidUTF8(const char * src,int size)20bool IsValidUTF8(const char *src, int size) { 21 for (int i = 0; i < size;) { 22 // Unexpected trail byte. 23 if (IsTrailByte(src[i])) { 24 return false; 25 } 26 27 const int num_codepoint_bytes = GetNumBytesForUTF8Char(&src[i]); 28 if (num_codepoint_bytes <= 0 || i + num_codepoint_bytes > size) { 29 return false; 30 } 31 32 // Check that remaining bytes in the codepoint are trailing bytes. 33 i++; 34 for (int k = 1; k < num_codepoint_bytes; k++, i++) { 35 if (!IsTrailByte(src[i])) { 36 return false; 37 } 38 } 39 } 40 return true; 41 } 42 } // namespace libtextclassifier2 43