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756 lines
22 KiB
756 lines
22 KiB
/* |
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* |
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* Copyright (c) 2004 |
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* John Maddock |
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* |
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* Use, modification and distribution are subject to the |
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* Boost Software License, Version 1.0. (See accompanying file |
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* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
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* |
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*/ |
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/* |
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* LOCATION: see http://www.boost.org for most recent version. |
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* FILE unicode_iterator.hpp |
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* VERSION see <boost/version.hpp> |
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* DESCRIPTION: Iterator adapters for converting between different Unicode encodings. |
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*/ |
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/**************************************************************************** |
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Contents: |
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~~~~~~~~~ |
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1) Read Only, Input Adapters: |
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
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template <class BaseIterator, class U8Type = ::boost::uint8_t> |
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class u32_to_u8_iterator; |
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Adapts sequence of UTF-32 code points to "look like" a sequence of UTF-8. |
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template <class BaseIterator, class U32Type = ::boost::uint32_t> |
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class u8_to_u32_iterator; |
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Adapts sequence of UTF-8 code points to "look like" a sequence of UTF-32. |
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template <class BaseIterator, class U16Type = ::boost::uint16_t> |
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class u32_to_u16_iterator; |
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Adapts sequence of UTF-32 code points to "look like" a sequence of UTF-16. |
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template <class BaseIterator, class U32Type = ::boost::uint32_t> |
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class u16_to_u32_iterator; |
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Adapts sequence of UTF-16 code points to "look like" a sequence of UTF-32. |
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2) Single pass output iterator adapters: |
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template <class BaseIterator> |
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class utf8_output_iterator; |
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Accepts UTF-32 code points and forwards them on as UTF-8 code points. |
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template <class BaseIterator> |
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class utf16_output_iterator; |
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Accepts UTF-32 code points and forwards them on as UTF-16 code points. |
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****************************************************************************/ |
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#ifndef BOOST_REGEX_UNICODE_ITERATOR_HPP |
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#define BOOST_REGEX_UNICODE_ITERATOR_HPP |
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#include <boost/cstdint.hpp> |
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#include <boost/assert.hpp> |
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#include <boost/iterator/iterator_facade.hpp> |
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#include <boost/static_assert.hpp> |
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#include <boost/throw_exception.hpp> |
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#include <stdexcept> |
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#ifndef BOOST_NO_STD_LOCALE |
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#include <sstream> |
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#include <ios> |
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#endif |
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#include <limits.h> // CHAR_BIT |
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namespace boost{ |
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namespace detail{ |
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static const ::boost::uint16_t high_surrogate_base = 0xD7C0u; |
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static const ::boost::uint16_t low_surrogate_base = 0xDC00u; |
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static const ::boost::uint32_t ten_bit_mask = 0x3FFu; |
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inline bool is_high_surrogate(::boost::uint16_t v) |
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{ |
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return (v & 0xFFFFFC00u) == 0xd800u; |
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} |
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inline bool is_low_surrogate(::boost::uint16_t v) |
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{ |
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return (v & 0xFFFFFC00u) == 0xdc00u; |
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} |
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template <class T> |
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inline bool is_surrogate(T v) |
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{ |
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return (v & 0xFFFFF800u) == 0xd800; |
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} |
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inline unsigned utf8_byte_count(boost::uint8_t c) |
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{ |
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// if the most significant bit with a zero in it is in position |
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// 8-N then there are N bytes in this UTF-8 sequence: |
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boost::uint8_t mask = 0x80u; |
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unsigned result = 0; |
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while(c & mask) |
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{ |
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++result; |
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mask >>= 1; |
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} |
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return (result == 0) ? 1 : ((result > 4) ? 4 : result); |
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} |
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inline unsigned utf8_trailing_byte_count(boost::uint8_t c) |
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{ |
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return utf8_byte_count(c) - 1; |
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} |
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#ifdef BOOST_MSVC |
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#pragma warning(push) |
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#pragma warning(disable:4100) |
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#endif |
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inline void invalid_utf32_code_point(::boost::uint32_t val) |
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{ |
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#ifndef BOOST_NO_STD_LOCALE |
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std::stringstream ss; |
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ss << "Invalid UTF-32 code point U+" << std::showbase << std::hex << val << " encountered while trying to encode UTF-16 sequence"; |
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std::out_of_range e(ss.str()); |
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#else |
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std::out_of_range e("Invalid UTF-32 code point encountered while trying to encode UTF-16 sequence"); |
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#endif |
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boost::throw_exception(e); |
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} |
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#ifdef BOOST_MSVC |
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#pragma warning(pop) |
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#endif |
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} // namespace detail |
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template <class BaseIterator, class U16Type = ::boost::uint16_t> |
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class u32_to_u16_iterator |
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: public boost::iterator_facade<u32_to_u16_iterator<BaseIterator, U16Type>, U16Type, std::bidirectional_iterator_tag, const U16Type> |
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{ |
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typedef boost::iterator_facade<u32_to_u16_iterator<BaseIterator, U16Type>, U16Type, std::bidirectional_iterator_tag, const U16Type> base_type; |
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#if !defined(BOOST_NO_STD_ITERATOR_TRAITS) && !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) |
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typedef typename std::iterator_traits<BaseIterator>::value_type base_value_type; |
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BOOST_STATIC_ASSERT(sizeof(base_value_type)*CHAR_BIT == 32); |
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BOOST_STATIC_ASSERT(sizeof(U16Type)*CHAR_BIT == 16); |
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#endif |
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public: |
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typename base_type::reference |
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dereference()const |
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{ |
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if(m_current == 2) |
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extract_current(); |
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return m_values[m_current]; |
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} |
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bool equal(const u32_to_u16_iterator& that)const |
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{ |
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if(m_position == that.m_position) |
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{ |
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// Both m_currents must be equal, or both even |
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// this is the same as saying their sum must be even: |
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return (m_current + that.m_current) & 1u ? false : true; |
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} |
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return false; |
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} |
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void increment() |
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{ |
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// if we have a pending read then read now, so that we know whether |
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// to skip a position, or move to a low-surrogate: |
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if(m_current == 2) |
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{ |
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// pending read: |
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extract_current(); |
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} |
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// move to the next surrogate position: |
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++m_current; |
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// if we've reached the end skip a position: |
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if(m_values[m_current] == 0) |
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{ |
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m_current = 2; |
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++m_position; |
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} |
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} |
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void decrement() |
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{ |
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if(m_current != 1) |
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{ |
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// decrementing an iterator always leads to a valid position: |
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--m_position; |
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extract_current(); |
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m_current = m_values[1] ? 1 : 0; |
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} |
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else |
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{ |
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m_current = 0; |
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} |
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} |
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BaseIterator base()const |
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{ |
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return m_position; |
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} |
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// construct: |
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u32_to_u16_iterator() : m_position(), m_current(0) |
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{ |
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m_values[0] = 0; |
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m_values[1] = 0; |
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m_values[2] = 0; |
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} |
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u32_to_u16_iterator(BaseIterator b) : m_position(b), m_current(2) |
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{ |
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m_values[0] = 0; |
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m_values[1] = 0; |
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m_values[2] = 0; |
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} |
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private: |
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void extract_current()const |
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{ |
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// begin by checking for a code point out of range: |
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::boost::uint32_t v = *m_position; |
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if(v >= 0x10000u) |
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{ |
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if(v > 0x10FFFFu) |
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detail::invalid_utf32_code_point(*m_position); |
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// split into two surrogates: |
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m_values[0] = static_cast<U16Type>(v >> 10) + detail::high_surrogate_base; |
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m_values[1] = static_cast<U16Type>(v & detail::ten_bit_mask) + detail::low_surrogate_base; |
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m_current = 0; |
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BOOST_ASSERT(detail::is_high_surrogate(m_values[0])); |
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BOOST_ASSERT(detail::is_low_surrogate(m_values[1])); |
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} |
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else |
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{ |
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// 16-bit code point: |
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m_values[0] = static_cast<U16Type>(*m_position); |
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m_values[1] = 0; |
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m_current = 0; |
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// value must not be a surrogate: |
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if(detail::is_surrogate(m_values[0])) |
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detail::invalid_utf32_code_point(*m_position); |
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} |
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} |
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BaseIterator m_position; |
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mutable U16Type m_values[3]; |
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mutable unsigned m_current; |
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}; |
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template <class BaseIterator, class U32Type = ::boost::uint32_t> |
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class u16_to_u32_iterator |
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: public boost::iterator_facade<u16_to_u32_iterator<BaseIterator, U32Type>, U32Type, std::bidirectional_iterator_tag, const U32Type> |
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{ |
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typedef boost::iterator_facade<u16_to_u32_iterator<BaseIterator, U32Type>, U32Type, std::bidirectional_iterator_tag, const U32Type> base_type; |
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// special values for pending iterator reads: |
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BOOST_STATIC_CONSTANT(U32Type, pending_read = 0xffffffffu); |
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#if !defined(BOOST_NO_STD_ITERATOR_TRAITS) && !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) |
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typedef typename std::iterator_traits<BaseIterator>::value_type base_value_type; |
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BOOST_STATIC_ASSERT(sizeof(base_value_type)*CHAR_BIT == 16); |
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BOOST_STATIC_ASSERT(sizeof(U32Type)*CHAR_BIT == 32); |
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#endif |
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public: |
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typename base_type::reference |
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dereference()const |
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{ |
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if(m_value == pending_read) |
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extract_current(); |
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return m_value; |
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} |
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bool equal(const u16_to_u32_iterator& that)const |
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{ |
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return m_position == that.m_position; |
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} |
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void increment() |
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{ |
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// skip high surrogate first if there is one: |
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if(detail::is_high_surrogate(*m_position)) ++m_position; |
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++m_position; |
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m_value = pending_read; |
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} |
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void decrement() |
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{ |
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--m_position; |
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// if we have a low surrogate then go back one more: |
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if(detail::is_low_surrogate(*m_position)) |
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--m_position; |
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m_value = pending_read; |
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} |
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BaseIterator base()const |
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{ |
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return m_position; |
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} |
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// construct: |
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u16_to_u32_iterator() : m_position() |
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{ |
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m_value = pending_read; |
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} |
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u16_to_u32_iterator(BaseIterator b) : m_position(b) |
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{ |
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m_value = pending_read; |
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} |
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// |
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// Range checked version: |
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// |
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u16_to_u32_iterator(BaseIterator b, BaseIterator start, BaseIterator end) : m_position(b) |
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{ |
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m_value = pending_read; |
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// |
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// The range must not start with a low surrogate, or end in a high surrogate, |
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// otherwise we run the risk of running outside the underlying input range. |
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// Likewise b must not be located at a low surrogate. |
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// |
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boost::uint16_t val; |
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if(start != end) |
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{ |
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if((b != start) && (b != end)) |
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{ |
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val = *b; |
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if(detail::is_surrogate(val) && ((val & 0xFC00u) == 0xDC00u)) |
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invalid_code_point(val); |
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} |
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val = *start; |
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if(detail::is_surrogate(val) && ((val & 0xFC00u) == 0xDC00u)) |
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invalid_code_point(val); |
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val = *--end; |
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if(detail::is_high_surrogate(val)) |
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invalid_code_point(val); |
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} |
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} |
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private: |
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static void invalid_code_point(::boost::uint16_t val) |
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{ |
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#ifndef BOOST_NO_STD_LOCALE |
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std::stringstream ss; |
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ss << "Misplaced UTF-16 surrogate U+" << std::showbase << std::hex << val << " encountered while trying to encode UTF-32 sequence"; |
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std::out_of_range e(ss.str()); |
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#else |
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std::out_of_range e("Misplaced UTF-16 surrogate encountered while trying to encode UTF-32 sequence"); |
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#endif |
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boost::throw_exception(e); |
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} |
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void extract_current()const |
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{ |
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m_value = static_cast<U32Type>(static_cast< ::boost::uint16_t>(*m_position)); |
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// if the last value is a high surrogate then adjust m_position and m_value as needed: |
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if(detail::is_high_surrogate(*m_position)) |
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{ |
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// precondition; next value must have be a low-surrogate: |
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BaseIterator next(m_position); |
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::boost::uint16_t t = *++next; |
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if((t & 0xFC00u) != 0xDC00u) |
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invalid_code_point(t); |
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m_value = (m_value - detail::high_surrogate_base) << 10; |
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m_value |= (static_cast<U32Type>(static_cast< ::boost::uint16_t>(t)) & detail::ten_bit_mask); |
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} |
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// postcondition; result must not be a surrogate: |
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if(detail::is_surrogate(m_value)) |
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invalid_code_point(static_cast< ::boost::uint16_t>(m_value)); |
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} |
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BaseIterator m_position; |
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mutable U32Type m_value; |
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}; |
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template <class BaseIterator, class U8Type = ::boost::uint8_t> |
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class u32_to_u8_iterator |
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: public boost::iterator_facade<u32_to_u8_iterator<BaseIterator, U8Type>, U8Type, std::bidirectional_iterator_tag, const U8Type> |
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{ |
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typedef boost::iterator_facade<u32_to_u8_iterator<BaseIterator, U8Type>, U8Type, std::bidirectional_iterator_tag, const U8Type> base_type; |
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#if !defined(BOOST_NO_STD_ITERATOR_TRAITS) && !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) |
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typedef typename std::iterator_traits<BaseIterator>::value_type base_value_type; |
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BOOST_STATIC_ASSERT(sizeof(base_value_type)*CHAR_BIT == 32); |
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BOOST_STATIC_ASSERT(sizeof(U8Type)*CHAR_BIT == 8); |
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#endif |
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public: |
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typename base_type::reference |
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dereference()const |
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{ |
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if(m_current == 4) |
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extract_current(); |
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return m_values[m_current]; |
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} |
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bool equal(const u32_to_u8_iterator& that)const |
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{ |
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if(m_position == that.m_position) |
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{ |
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// either the m_current's must be equal, or one must be 0 and |
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// the other 4: which means neither must have bits 1 or 2 set: |
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return (m_current == that.m_current) |
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|| (((m_current | that.m_current) & 3) == 0); |
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} |
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return false; |
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} |
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void increment() |
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{ |
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// if we have a pending read then read now, so that we know whether |
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// to skip a position, or move to a low-surrogate: |
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if(m_current == 4) |
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{ |
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// pending read: |
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extract_current(); |
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} |
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// move to the next surrogate position: |
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++m_current; |
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// if we've reached the end skip a position: |
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if(m_values[m_current] == 0) |
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{ |
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m_current = 4; |
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++m_position; |
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} |
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} |
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void decrement() |
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{ |
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if((m_current & 3) == 0) |
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{ |
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--m_position; |
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extract_current(); |
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m_current = 3; |
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while(m_current && (m_values[m_current] == 0)) |
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--m_current; |
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} |
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else |
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--m_current; |
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} |
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BaseIterator base()const |
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{ |
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return m_position; |
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} |
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// construct: |
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u32_to_u8_iterator() : m_position(), m_current(0) |
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{ |
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m_values[0] = 0; |
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m_values[1] = 0; |
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m_values[2] = 0; |
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m_values[3] = 0; |
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m_values[4] = 0; |
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} |
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u32_to_u8_iterator(BaseIterator b) : m_position(b), m_current(4) |
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{ |
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m_values[0] = 0; |
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m_values[1] = 0; |
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m_values[2] = 0; |
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m_values[3] = 0; |
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m_values[4] = 0; |
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} |
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private: |
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void extract_current()const |
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{ |
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boost::uint32_t c = *m_position; |
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if(c > 0x10FFFFu) |
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detail::invalid_utf32_code_point(c); |
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if(c < 0x80u) |
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{ |
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m_values[0] = static_cast<unsigned char>(c); |
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m_values[1] = static_cast<unsigned char>(0u); |
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m_values[2] = static_cast<unsigned char>(0u); |
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m_values[3] = static_cast<unsigned char>(0u); |
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} |
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else if(c < 0x800u) |
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{ |
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m_values[0] = static_cast<unsigned char>(0xC0u + (c >> 6)); |
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m_values[1] = static_cast<unsigned char>(0x80u + (c & 0x3Fu)); |
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m_values[2] = static_cast<unsigned char>(0u); |
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m_values[3] = static_cast<unsigned char>(0u); |
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} |
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else if(c < 0x10000u) |
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{ |
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m_values[0] = static_cast<unsigned char>(0xE0u + (c >> 12)); |
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m_values[1] = static_cast<unsigned char>(0x80u + ((c >> 6) & 0x3Fu)); |
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m_values[2] = static_cast<unsigned char>(0x80u + (c & 0x3Fu)); |
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m_values[3] = static_cast<unsigned char>(0u); |
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} |
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else |
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{ |
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m_values[0] = static_cast<unsigned char>(0xF0u + (c >> 18)); |
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m_values[1] = static_cast<unsigned char>(0x80u + ((c >> 12) & 0x3Fu)); |
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m_values[2] = static_cast<unsigned char>(0x80u + ((c >> 6) & 0x3Fu)); |
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m_values[3] = static_cast<unsigned char>(0x80u + (c & 0x3Fu)); |
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} |
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m_current= 0; |
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} |
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BaseIterator m_position; |
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mutable U8Type m_values[5]; |
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mutable unsigned m_current; |
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}; |
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template <class BaseIterator, class U32Type = ::boost::uint32_t> |
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class u8_to_u32_iterator |
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: public boost::iterator_facade<u8_to_u32_iterator<BaseIterator, U32Type>, U32Type, std::bidirectional_iterator_tag, const U32Type> |
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{ |
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typedef boost::iterator_facade<u8_to_u32_iterator<BaseIterator, U32Type>, U32Type, std::bidirectional_iterator_tag, const U32Type> base_type; |
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// special values for pending iterator reads: |
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BOOST_STATIC_CONSTANT(U32Type, pending_read = 0xffffffffu); |
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#if !defined(BOOST_NO_STD_ITERATOR_TRAITS) && !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) |
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typedef typename std::iterator_traits<BaseIterator>::value_type base_value_type; |
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BOOST_STATIC_ASSERT(sizeof(base_value_type)*CHAR_BIT == 8); |
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BOOST_STATIC_ASSERT(sizeof(U32Type)*CHAR_BIT == 32); |
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#endif |
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public: |
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typename base_type::reference |
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dereference()const |
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{ |
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if(m_value == pending_read) |
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extract_current(); |
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return m_value; |
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} |
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bool equal(const u8_to_u32_iterator& that)const |
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{ |
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return m_position == that.m_position; |
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} |
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void increment() |
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{ |
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// skip high surrogate first if there is one: |
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unsigned c = detail::utf8_byte_count(*m_position); |
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std::advance(m_position, c); |
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m_value = pending_read; |
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} |
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void decrement() |
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{ |
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// Keep backtracking until we don't have a trailing character: |
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unsigned count = 0; |
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while((*--m_position & 0xC0u) == 0x80u) ++count; |
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// now check that the sequence was valid: |
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if(count != detail::utf8_trailing_byte_count(*m_position)) |
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invalid_sequence(); |
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m_value = pending_read; |
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} |
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BaseIterator base()const |
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{ |
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return m_position; |
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} |
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// construct: |
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u8_to_u32_iterator() : m_position() |
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{ |
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m_value = pending_read; |
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} |
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u8_to_u32_iterator(BaseIterator b) : m_position(b) |
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{ |
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m_value = pending_read; |
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} |
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// |
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// Checked constructor: |
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// |
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u8_to_u32_iterator(BaseIterator b, BaseIterator start, BaseIterator end) : m_position(b) |
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{ |
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m_value = pending_read; |
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// |
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// We must not start with a continuation character, or end with a |
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// truncated UTF-8 sequence otherwise we run the risk of going past |
|
// the start/end of the underlying sequence: |
|
// |
|
if(start != end) |
|
{ |
|
unsigned char v = *start; |
|
if((v & 0xC0u) == 0x80u) |
|
invalid_sequence(); |
|
if((b != start) && (b != end) && ((*b & 0xC0u) == 0x80u)) |
|
invalid_sequence(); |
|
BaseIterator pos = end; |
|
do |
|
{ |
|
v = *--pos; |
|
} |
|
while((start != pos) && ((v & 0xC0u) == 0x80u)); |
|
std::ptrdiff_t extra = detail::utf8_byte_count(v); |
|
if(std::distance(pos, end) < extra) |
|
invalid_sequence(); |
|
} |
|
} |
|
private: |
|
static void invalid_sequence() |
|
{ |
|
std::out_of_range e("Invalid UTF-8 sequence encountered while trying to encode UTF-32 character"); |
|
boost::throw_exception(e); |
|
} |
|
void extract_current()const |
|
{ |
|
m_value = static_cast<U32Type>(static_cast< ::boost::uint8_t>(*m_position)); |
|
// we must not have a continuation character: |
|
if((m_value & 0xC0u) == 0x80u) |
|
invalid_sequence(); |
|
// see how many extra byts we have: |
|
unsigned extra = detail::utf8_trailing_byte_count(*m_position); |
|
// extract the extra bits, 6 from each extra byte: |
|
BaseIterator next(m_position); |
|
for(unsigned c = 0; c < extra; ++c) |
|
{ |
|
++next; |
|
m_value <<= 6; |
|
m_value += static_cast<boost::uint8_t>(*next) & 0x3Fu; |
|
} |
|
// we now need to remove a few of the leftmost bits, but how many depends |
|
// upon how many extra bytes we've extracted: |
|
static const boost::uint32_t masks[4] = |
|
{ |
|
0x7Fu, |
|
0x7FFu, |
|
0xFFFFu, |
|
0x1FFFFFu, |
|
}; |
|
m_value &= masks[extra]; |
|
// check the result: |
|
if(m_value > static_cast<U32Type>(0x10FFFFu)) |
|
invalid_sequence(); |
|
} |
|
BaseIterator m_position; |
|
mutable U32Type m_value; |
|
}; |
|
|
|
template <class BaseIterator> |
|
class utf16_output_iterator |
|
{ |
|
public: |
|
typedef void difference_type; |
|
typedef void value_type; |
|
typedef boost::uint32_t* pointer; |
|
typedef boost::uint32_t& reference; |
|
typedef std::output_iterator_tag iterator_category; |
|
|
|
utf16_output_iterator(const BaseIterator& b) |
|
: m_position(b){} |
|
utf16_output_iterator(const utf16_output_iterator& that) |
|
: m_position(that.m_position){} |
|
utf16_output_iterator& operator=(const utf16_output_iterator& that) |
|
{ |
|
m_position = that.m_position; |
|
return *this; |
|
} |
|
const utf16_output_iterator& operator*()const |
|
{ |
|
return *this; |
|
} |
|
void operator=(boost::uint32_t val)const |
|
{ |
|
push(val); |
|
} |
|
utf16_output_iterator& operator++() |
|
{ |
|
return *this; |
|
} |
|
utf16_output_iterator& operator++(int) |
|
{ |
|
return *this; |
|
} |
|
BaseIterator base()const |
|
{ |
|
return m_position; |
|
} |
|
private: |
|
void push(boost::uint32_t v)const |
|
{ |
|
if(v >= 0x10000u) |
|
{ |
|
// begin by checking for a code point out of range: |
|
if(v > 0x10FFFFu) |
|
detail::invalid_utf32_code_point(v); |
|
// split into two surrogates: |
|
*m_position++ = static_cast<boost::uint16_t>(v >> 10) + detail::high_surrogate_base; |
|
*m_position++ = static_cast<boost::uint16_t>(v & detail::ten_bit_mask) + detail::low_surrogate_base; |
|
} |
|
else |
|
{ |
|
// 16-bit code point: |
|
// value must not be a surrogate: |
|
if(detail::is_surrogate(v)) |
|
detail::invalid_utf32_code_point(v); |
|
*m_position++ = static_cast<boost::uint16_t>(v); |
|
} |
|
} |
|
mutable BaseIterator m_position; |
|
}; |
|
|
|
template <class BaseIterator> |
|
class utf8_output_iterator |
|
{ |
|
public: |
|
typedef void difference_type; |
|
typedef void value_type; |
|
typedef boost::uint32_t* pointer; |
|
typedef boost::uint32_t& reference; |
|
typedef std::output_iterator_tag iterator_category; |
|
|
|
utf8_output_iterator(const BaseIterator& b) |
|
: m_position(b){} |
|
utf8_output_iterator(const utf8_output_iterator& that) |
|
: m_position(that.m_position){} |
|
utf8_output_iterator& operator=(const utf8_output_iterator& that) |
|
{ |
|
m_position = that.m_position; |
|
return *this; |
|
} |
|
const utf8_output_iterator& operator*()const |
|
{ |
|
return *this; |
|
} |
|
void operator=(boost::uint32_t val)const |
|
{ |
|
push(val); |
|
} |
|
utf8_output_iterator& operator++() |
|
{ |
|
return *this; |
|
} |
|
utf8_output_iterator& operator++(int) |
|
{ |
|
return *this; |
|
} |
|
BaseIterator base()const |
|
{ |
|
return m_position; |
|
} |
|
private: |
|
void push(boost::uint32_t c)const |
|
{ |
|
if(c > 0x10FFFFu) |
|
detail::invalid_utf32_code_point(c); |
|
if(c < 0x80u) |
|
{ |
|
*m_position++ = static_cast<unsigned char>(c); |
|
} |
|
else if(c < 0x800u) |
|
{ |
|
*m_position++ = static_cast<unsigned char>(0xC0u + (c >> 6)); |
|
*m_position++ = static_cast<unsigned char>(0x80u + (c & 0x3Fu)); |
|
} |
|
else if(c < 0x10000u) |
|
{ |
|
*m_position++ = static_cast<unsigned char>(0xE0u + (c >> 12)); |
|
*m_position++ = static_cast<unsigned char>(0x80u + ((c >> 6) & 0x3Fu)); |
|
*m_position++ = static_cast<unsigned char>(0x80u + (c & 0x3Fu)); |
|
} |
|
else |
|
{ |
|
*m_position++ = static_cast<unsigned char>(0xF0u + (c >> 18)); |
|
*m_position++ = static_cast<unsigned char>(0x80u + ((c >> 12) & 0x3Fu)); |
|
*m_position++ = static_cast<unsigned char>(0x80u + ((c >> 6) & 0x3Fu)); |
|
*m_position++ = static_cast<unsigned char>(0x80u + (c & 0x3Fu)); |
|
} |
|
} |
|
mutable BaseIterator m_position; |
|
}; |
|
|
|
} // namespace boost |
|
|
|
#endif // BOOST_REGEX_UNICODE_ITERATOR_HPP |
|
|
|
|