| /* |
| * Copyright (C) 2003, 2006, 2008, 2009, 2010, 2011 Apple Inc. All rights |
| * reserved. |
| * Copyright (C) 2008 Holger Hans Peter Freyther |
| * Copyright (C) Research In Motion Limited 2011. All rights reserved. |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public License |
| * along with this library; see the file COPYING.LIB. If not, write to |
| * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| * |
| */ |
| |
| #include "platform/fonts/UTF16TextIterator.h" |
| |
| using namespace WTF; |
| using namespace Unicode; |
| |
| namespace blink { |
| |
| UTF16TextIterator::UTF16TextIterator(const UChar* characters, int length) |
| : m_characters(characters), |
| m_charactersEnd(characters + length), |
| m_offset(0), |
| m_endOffset(length), |
| m_currentGlyphLength(0) {} |
| |
| UTF16TextIterator::UTF16TextIterator(const UChar* characters, |
| int currentCharacter, |
| int endOffset, |
| int endCharacter) |
| : m_characters(characters), |
| m_charactersEnd(characters + (endCharacter - currentCharacter)), |
| m_offset(currentCharacter), |
| m_endOffset(endOffset), |
| m_currentGlyphLength(0) {} |
| |
| bool UTF16TextIterator::isValidSurrogatePair(UChar32& character) { |
| // If we have a surrogate pair, make sure it starts with the high part. |
| if (!U16_IS_SURROGATE_LEAD(character)) |
| return false; |
| |
| // Do we have a surrogate pair? If so, determine the full Unicode (32 bit) |
| // code point before glyph lookup. |
| // Make sure we have another character and it's a low surrogate. |
| if (m_characters + 1 >= m_charactersEnd) |
| return false; |
| |
| UChar low = m_characters[1]; |
| if (!U16_IS_TRAIL(low)) |
| return false; |
| return true; |
| } |
| |
| bool UTF16TextIterator::consumeSurrogatePair(UChar32& character) { |
| ASSERT(U16_IS_SURROGATE(character)); |
| |
| if (!isValidSurrogatePair(character)) { |
| character = replacementCharacter; |
| return true; |
| } |
| |
| UChar low = m_characters[1]; |
| character = U16_GET_SUPPLEMENTARY(character, low); |
| m_currentGlyphLength = 2; |
| return true; |
| } |
| |
| } // namespace blink |