/*
 *
 * Copyright (c) 2004 John Maddock
 * Copyright 2011 Garmin Ltd. or its subsidiaries
 *
 * Use, modification and distribution are subject to the
 * Boost Software License, Version 1.0. (See accompanying file
 * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 *
 */

/*
 *   LOCATION:    see http://www.boost.org for most recent version.
 *   FILE         cpp_regex_traits.hpp
 *   VERSION      see <boost/version.hpp>
 *   DESCRIPTION: Declares regular expression traits class cpp_regex_traits.
 */

#ifndef BOOST_CPP_REGEX_TRAITS_HPP_INCLUDED
#define BOOST_CPP_REGEX_TRAITS_HPP_INCLUDED

#include <boost/config.hpp>
#include <boost/integer.hpp>
#include <boost/type_traits/make_unsigned.hpp>

#ifndef BOOST_NO_STD_LOCALE

#ifndef BOOST_RE_PAT_EXCEPT_HPP
#include <boost/regex/pattern_except.hpp>
#endif
#ifndef BOOST_REGEX_TRAITS_DEFAULTS_HPP_INCLUDED
#include <boost/regex/v4/regex_traits_defaults.hpp>
#endif
#ifdef BOOST_HAS_THREADS
#include <boost/regex/pending/static_mutex.hpp>
#endif
#ifndef BOOST_REGEX_PRIMARY_TRANSFORM
#include <boost/regex/v4/primary_transform.hpp>
#endif
#ifndef BOOST_REGEX_OBJECT_CACHE_HPP
#include <boost/regex/v4/object_cache.hpp>
#endif

#include <climits>
#include <ios>
#include <istream>

#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable: 4103)
#endif
#ifdef BOOST_HAS_ABI_HEADERS
#  include BOOST_ABI_PREFIX
#endif
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif

#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable:4786 4251)
#endif

namespace boost {

//
// forward declaration is needed by some compilers:
//
template <class charT>
class cpp_regex_traits;

namespace BOOST_REGEX_DETAIL_NS {

//
// class parser_buf:
// acts as a stream buffer which wraps around a pair of pointers:
//
template <class charT,
          class traits = ::std::char_traits<charT> >
class parser_buf : public ::std::basic_streambuf<charT, traits>
{
    typedef ::std::basic_streambuf<charT, traits> base_type;
    typedef typename base_type::int_type int_type;
    typedef typename base_type::char_type char_type;
    typedef typename base_type::pos_type pos_type;
    typedef ::std::streamsize streamsize;
    typedef typename base_type::off_type off_type;
  public:
    parser_buf() : base_type()
    {
        setbuf(0, 0);
    }
    const charT*
    getnext()
    {
        return this->gptr();
    }
  protected:
    std::basic_streambuf<charT, traits>*
    setbuf(char_type* s, streamsize n) BOOST_OVERRIDE;
    typename parser_buf<charT, traits>::pos_type
    seekpos(pos_type sp, ::std::ios_base::openmode which) BOOST_OVERRIDE;
    typename parser_buf<charT, traits>::pos_type
    seekoff(off_type off, ::std::ios_base::seekdir way, ::std::ios_base::openmode which) BOOST_OVERRIDE;
  private:
    parser_buf&
    operator=(const parser_buf&);
    parser_buf(const parser_buf&);
};

template<class charT, class traits>
std::basic_streambuf<charT, traits>*
parser_buf<charT, traits>::setbuf(char_type* s, streamsize n)
{
    this->setg(s, s, s + n);
    return this;
}

template<class charT, class traits>
typename parser_buf<charT, traits>::pos_type
parser_buf<charT, traits>::seekoff(off_type off, ::std::ios_base::seekdir way, ::std::ios_base::openmode which)
{
    typedef typename boost::int_t<sizeof(way) * CHAR_BIT>::least cast_type;

    if (which & ::std::ios_base::out)
    {
        return pos_type(off_type(-1));
    }

    std::ptrdiff_t size = this->egptr() - this->eback();
    std::ptrdiff_t pos = this->gptr() - this->eback();
    charT* g = this->eback();

    switch (static_cast<cast_type>(way))
    {
    case ::std::ios_base::beg:
        if ((off < 0) || (off > size))
        {
            return pos_type(off_type(-1));
        }

        else
        {
            this->setg(g, g + off, g + size);
        }

        break;

    case ::std::ios_base::end:
        if ((off < 0) || (off > size))
        {
            return pos_type(off_type(-1));
        }

        else
        {
            this->setg(g, g + size - off, g + size);
        }

        break;

    case ::std::ios_base::cur:
    {
        std::ptrdiff_t newpos = static_cast<std::ptrdiff_t>(pos + off);

        if ((newpos < 0) || (newpos > size))
        {
            return pos_type(off_type(-1));
        }

        else
        {
            this->setg(g, g + newpos, g + size);
        }

        break;
    }

    default:
        ;
    }

#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable:4244)
#endif
    return static_cast<pos_type>(this->gptr() - this->eback());
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif
}

template<class charT, class traits>
typename parser_buf<charT, traits>::pos_type
parser_buf<charT, traits>::seekpos(pos_type sp, ::std::ios_base::openmode which)
{
    if (which & ::std::ios_base::out)
    {
        return pos_type(off_type(-1));
    }

    off_type size = static_cast<off_type>(this->egptr() - this->eback());
    charT* g = this->eback();

    if (off_type(sp) <= size)
    {
        this->setg(g, g + off_type(sp), g + size);
    }

    return pos_type(off_type(-1));
}

//
// class cpp_regex_traits_base:
// acts as a container for locale and the facets we are using.
//
template <class charT>
struct cpp_regex_traits_base
{
    cpp_regex_traits_base(const std::locale& l)
    {
        (void)imbue(l);
    }
    std::locale
    imbue(const std::locale& l);

    std::locale m_locale;
    std::ctype<charT> const* m_pctype;
#ifndef BOOST_NO_STD_MESSAGES
    std::messages<charT> const* m_pmessages;
#endif
    std::collate<charT> const* m_pcollate;

    bool
    operator<(const cpp_regex_traits_base& b)const
    {
        if (m_pctype == b.m_pctype)
        {
#ifndef BOOST_NO_STD_MESSAGES

            if (m_pmessages == b.m_pmessages)
            {
                return m_pcollate < b.m_pcollate;
            }

            return m_pmessages < b.m_pmessages;
#else
            return m_pcollate < b.m_pcollate;
#endif
        }

        return m_pctype < b.m_pctype;
    }
    bool
    operator==(const cpp_regex_traits_base& b)const
    {
        return (m_pctype == b.m_pctype)
#ifndef BOOST_NO_STD_MESSAGES
               && (m_pmessages == b.m_pmessages)
#endif
               && (m_pcollate == b.m_pcollate);
    }
};

template <class charT>
std::locale
cpp_regex_traits_base<charT>::imbue(const std::locale& l)
{
    std::locale result(m_locale);
    m_locale = l;
    m_pctype = &BOOST_USE_FACET(std::ctype<charT>, l);
#ifndef BOOST_NO_STD_MESSAGES
    m_pmessages = BOOST_HAS_FACET(std::messages<charT>, l) ? &BOOST_USE_FACET(std::messages<charT>, l) : 0;
#endif
    m_pcollate = &BOOST_USE_FACET(std::collate<charT>, l);
    return result;
}

//
// class cpp_regex_traits_char_layer:
// implements methods that require specialization for narrow characters:
//
template <class charT>
class cpp_regex_traits_char_layer : public cpp_regex_traits_base<charT>
{
    typedef std::basic_string<charT> string_type;
    typedef std::map<charT, regex_constants::syntax_type> map_type;
    typedef typename map_type::const_iterator map_iterator_type;
  public:
    cpp_regex_traits_char_layer(const std::locale& l)
        : cpp_regex_traits_base<charT>(l)
    {
        init();
    }
    cpp_regex_traits_char_layer(const cpp_regex_traits_base<charT>& b)
        : cpp_regex_traits_base<charT>(b)
    {
        init();
    }
    void
    init();

    regex_constants::syntax_type
    syntax_type(charT c)const
    {
        map_iterator_type i = m_char_map.find(c);
        return ((i == m_char_map.end()) ? 0 : i->second);
    }
    regex_constants::escape_syntax_type
    escape_syntax_type(charT c) const
    {
        map_iterator_type i = m_char_map.find(c);

        if (i == m_char_map.end())
        {
            if (this->m_pctype->is(std::ctype_base::lower, c))
            {
                return regex_constants::escape_type_class;
            }

            if (this->m_pctype->is(std::ctype_base::upper, c))
            {
                return regex_constants::escape_type_not_class;
            }

            return 0;
        }

        return i->second;
    }

  private:
    string_type
    get_default_message(regex_constants::syntax_type);
    // TODO: use a hash table when available!
    map_type m_char_map;
};

template <class charT>
void
cpp_regex_traits_char_layer<charT>::init()
{
    // we need to start by initialising our syntax map so we know which
    // character is used for which purpose:
#ifndef BOOST_NO_STD_MESSAGES
#ifndef __IBMCPP__
    typename std::messages<charT>::catalog cat = static_cast<std::messages<char>::catalog>(-1);
#else
    typename std::messages<charT>::catalog cat = reinterpret_cast<std::messages<char>::catalog>(-1);
#endif
    std::string cat_name(cpp_regex_traits<charT>::get_catalog_name());

    if ((!cat_name.empty()) && (this->m_pmessages != 0))
    {
        cat = this->m_pmessages->open(
                  cat_name,
                  this->m_locale);

        if ((int)cat < 0)
        {
            std::string m("Unable to open message catalog: ");
            std::runtime_error err(m + cat_name);
            boost::BOOST_REGEX_DETAIL_NS::raise_runtime_error(err);
        }
    }

    //
    // if we have a valid catalog then load our messages:
    //
    if ((int)cat >= 0)
    {
#ifndef BOOST_NO_EXCEPTIONS

        try
        {
#endif

            for (regex_constants::syntax_type i = 1; i < regex_constants::syntax_max; ++i)
            {
                string_type mss = this->m_pmessages->get(cat, 0, i, get_default_message(i));

                for (typename string_type::size_type j = 0; j < mss.size(); ++j)
                {
                    m_char_map[mss[j]] = i;
                }
            }

            this->m_pmessages->close(cat);
#ifndef BOOST_NO_EXCEPTIONS
        }

        catch (...)
        {
            if (this->m_pmessages)
            {
                this->m_pmessages->close(cat);
            }

            throw;
        }

#endif
    }

    else
    {
#endif

        for (regex_constants::syntax_type i = 1; i < regex_constants::syntax_max; ++i)
        {
            const char* ptr = get_default_syntax(i);

            while (ptr && *ptr)
            {
                m_char_map[this->m_pctype->widen(*ptr)] = i;
                ++ptr;
            }
        }

#ifndef BOOST_NO_STD_MESSAGES
    }

#endif
}

template <class charT>
typename cpp_regex_traits_char_layer<charT>::string_type
cpp_regex_traits_char_layer<charT>::get_default_message(regex_constants::syntax_type i)
{
    const char* ptr = get_default_syntax(i);
    string_type result;

    while (ptr && *ptr)
    {
        result.append(1, this->m_pctype->widen(*ptr));
        ++ptr;
    }

    return result;
}

//
// specialized version for narrow characters:
//
template <>
class cpp_regex_traits_char_layer<char> : public cpp_regex_traits_base<char>
{
    typedef std::string string_type;
  public:
    cpp_regex_traits_char_layer(const std::locale& l)
        : cpp_regex_traits_base<char>(l)
    {
        init();
    }
    cpp_regex_traits_char_layer(const cpp_regex_traits_base<char>& l)
        : cpp_regex_traits_base<char>(l)
    {
        init();
    }

    regex_constants::syntax_type
    syntax_type(char c)const
    {
        return m_char_map[static_cast<unsigned char>(c)];
    }
    regex_constants::escape_syntax_type
    escape_syntax_type(char c) const
    {
        return m_char_map[static_cast<unsigned char>(c)];
    }

  private:
    regex_constants::syntax_type m_char_map[1u << CHAR_BIT];
    void
    init();
};

#ifdef BOOST_REGEX_BUGGY_CTYPE_FACET
enum
{
    char_class_space=1<<0,
    char_class_print=1<<1,
    char_class_cntrl=1<<2,
    char_class_upper=1<<3,
    char_class_lower=1<<4,
    char_class_alpha=1<<5,
    char_class_digit=1<<6,
    char_class_punct=1<<7,
    char_class_xdigit=1<<8,
    char_class_alnum=char_class_alpha|char_class_digit,
    char_class_graph=char_class_alnum|char_class_punct,
    char_class_blank=1<<9,
    char_class_word=1<<10,
    char_class_unicode=1<<11,
    char_class_horizontal_space=1<<12,
    char_class_vertical_space=1<<13
};

#endif

//
// class cpp_regex_traits_implementation:
// provides pimpl implementation for cpp_regex_traits.
//
template <class charT>
class cpp_regex_traits_implementation : public cpp_regex_traits_char_layer<charT>
{
  public:
    typedef typename cpp_regex_traits<charT>::char_class_type      char_class_type;
    typedef typename std::ctype<charT>::mask                       native_mask_type;
    typedef typename boost::make_unsigned<native_mask_type>::type  unsigned_native_mask_type;
#ifndef BOOST_REGEX_BUGGY_CTYPE_FACET
    BOOST_STATIC_CONSTANT(char_class_type, mask_blank = 1u << 24);
    BOOST_STATIC_CONSTANT(char_class_type, mask_word = 1u << 25);
    BOOST_STATIC_CONSTANT(char_class_type, mask_unicode = 1u << 26);
    BOOST_STATIC_CONSTANT(char_class_type, mask_horizontal = 1u << 27);
    BOOST_STATIC_CONSTANT(char_class_type, mask_vertical = 1u << 28);
#endif

    typedef std::basic_string<charT> string_type;
    typedef charT char_type;
    //cpp_regex_traits_implementation();
    cpp_regex_traits_implementation(const std::locale& l)
        : cpp_regex_traits_char_layer<charT>(l)
    {
        init();
    }
    cpp_regex_traits_implementation(const cpp_regex_traits_base<charT>& l)
        : cpp_regex_traits_char_layer<charT>(l)
    {
        init();
    }
    std::string
    error_string(regex_constants::error_type n) const
    {
        if (!m_error_strings.empty())
        {
            std::map<int, std::string>::const_iterator p = m_error_strings.find(n);
            return (p == m_error_strings.end()) ? std::string(get_default_error_string(n)) : p->second;
        }

        return get_default_error_string(n);
    }
    char_class_type
    lookup_classname(const charT* p1, const charT* p2) const
    {
        char_class_type result = lookup_classname_imp(p1, p2);

        if (result == 0)
        {
            string_type temp(p1, p2);
            this->m_pctype->tolower(&*temp.begin(), &*temp.begin() + temp.size());
            result = lookup_classname_imp(&*temp.begin(), &*temp.begin() + temp.size());
        }

        return result;
    }
    string_type
    lookup_collatename(const charT* p1, const charT* p2) const;
    string_type
    transform_primary(const charT* p1, const charT* p2) const;
    string_type
    transform(const charT* p1, const charT* p2) const;
  private:
    std::map<int, std::string>     m_error_strings;   // error messages indexed by numberic ID
    std::map<string_type, char_class_type>  m_custom_class_names; // character class names
    std::map<string_type, string_type>      m_custom_collate_names; // collating element names
    unsigned                       m_collate_type;    // the form of the collation string
    charT                          m_collate_delim;   // the collation group delimiter
    //
    // helpers:
    //
    char_class_type
    lookup_classname_imp(const charT* p1, const charT* p2) const;
    void
    init();
#ifdef BOOST_REGEX_BUGGY_CTYPE_FACET
  public:
    bool
    isctype(charT c, char_class_type m)const;
#endif
};

#ifndef BOOST_REGEX_BUGGY_CTYPE_FACET
#if !defined(BOOST_NO_INCLASS_MEMBER_INITIALIZATION)

template <class charT>
typename cpp_regex_traits_implementation<charT>::char_class_type const cpp_regex_traits_implementation<charT>::mask_blank;
template <class charT>
typename cpp_regex_traits_implementation<charT>::char_class_type const cpp_regex_traits_implementation<charT>::mask_word;
template <class charT>
typename cpp_regex_traits_implementation<charT>::char_class_type const cpp_regex_traits_implementation<charT>::mask_unicode;
template <class charT>
typename cpp_regex_traits_implementation<charT>::char_class_type const cpp_regex_traits_implementation<charT>::mask_vertical;
template <class charT>
typename cpp_regex_traits_implementation<charT>::char_class_type const cpp_regex_traits_implementation<charT>::mask_horizontal;

#endif
#endif

template <class charT>
typename cpp_regex_traits_implementation<charT>::string_type
cpp_regex_traits_implementation<charT>::transform_primary(const charT* p1, const charT* p2) const
{
    //
    // PRECONDITIONS:
    //
    // A bug in gcc 3.2 (and maybe other versions as well) treats
    // p1 as a null terminated string, for efficiency reasons
    // we work around this elsewhere, but just assert here that
    // we adhere to gcc's (buggy) preconditions...
    //
    BOOST_REGEX_ASSERT(*p2 == 0);
    string_type result;
#if defined(_CPPLIB_VER)

    //
    // A bug in VC11 and 12 causes the program to hang if we pass a null-string
    // to std::collate::transform, but only for certain locales :-(
    // Probably effects Intel and Clang or any compiler using the VC std library (Dinkumware).
    //
    if (*p1 == 0)
    {
        return string_type(1, charT(0));
    }

#endif
    //
    // swallowing all exceptions here is a bad idea
    // however at least one std lib will always throw
    // std::bad_alloc for certain arguments...
    //
#ifndef BOOST_NO_EXCEPTIONS

    try
    {
#endif

        //
        // What we do here depends upon the format of the sort key returned by
        // sort key returned by this->transform:
        //
        switch (m_collate_type)
        {
        case sort_C:
        case sort_unknown:
            // the best we can do is translate to lower case, then get a regular sort key:
        {
            result.assign(p1, p2);
            this->m_pctype->tolower(&*result.begin(), &*result.begin() + result.size());
            result = this->m_pcollate->transform(&*result.begin(), &*result.begin() + result.size());
            break;
        }

        case sort_fixed:
        {
            // get a regular sort key, and then truncate it:
            result.assign(this->m_pcollate->transform(p1, p2));
            result.erase(this->m_collate_delim);
            break;
        }

        case sort_delim:
            // get a regular sort key, and then truncate everything after the delim:
            result.assign(this->m_pcollate->transform(p1, p2));
            std::size_t i;

            for (i = 0; i < result.size(); ++i)
            {
                if (result[i] == m_collate_delim)
                {
                    break;
                }
            }

            result.erase(i);
            break;
        }

#ifndef BOOST_NO_EXCEPTIONS
    }

    catch (...) {}

#endif

    while ((!result.empty()) && (charT(0) == *result.rbegin()))
    {
        result.erase(result.size() - 1);
    }

    if (result.empty())
    {
        // character is ignorable at the primary level:
        result = string_type(1, charT(0));
    }

    return result;
}

template <class charT>
typename cpp_regex_traits_implementation<charT>::string_type
cpp_regex_traits_implementation<charT>::transform(const charT* p1, const charT* p2) const
{
    //
    // PRECONDITIONS:
    //
    // A bug in gcc 3.2 (and maybe other versions as well) treats
    // p1 as a null terminated string, for efficiency reasons
    // we work around this elsewhere, but just assert here that
    // we adhere to gcc's (buggy) preconditions...
    //
    BOOST_REGEX_ASSERT(*p2 == 0);
    //
    // swallowing all exceptions here is a bad idea
    // however at least one std lib will always throw
    // std::bad_alloc for certain arguments...
    //
    string_type result, result2;
#if defined(_CPPLIB_VER)

    //
    // A bug in VC11 and 12 causes the program to hang if we pass a null-string
    // to std::collate::transform, but only for certain locales :-(
    // Probably effects Intel and Clang or any compiler using the VC std library (Dinkumware).
    //
    if (*p1 == 0)
    {
        return result;
    }

#endif
#ifndef BOOST_NO_EXCEPTIONS

    try
    {
#endif
        result = this->m_pcollate->transform(p1, p2);
        //
        // Borland's STLPort version returns a NULL-terminated
        // string that has garbage at the end - each call to
        // std::collate<wchar_t>::transform returns a different string!
        // So as a workaround, we'll truncate the string at the first NULL
        // which _seems_ to work....
#if BOOST_WORKAROUND(BOOST_BORLANDC, < 0x580)
        result.erase(result.find(charT(0)));
#else

        //
        // some implementations (Dinkumware) append unnecessary trailing \0's:
        while ((!result.empty()) && (charT(0) == *result.rbegin()))
        {
            result.erase(result.size() - 1);
        }

#endif
        //
        // We may have NULL's used as separators between sections of the collate string,
        // an example would be Boost.Locale.  We have no way to detect this case via
        // #defines since this can be used with any compiler/platform combination.
        // Unfortunately our state machine (which was devised when all implementations
        // used underlying C language API's) can't cope with that case.  One workaround
        // is to replace each character with 2, fortunately this code isn't used that
        // much as this is now slower than before :-(
        //
        typedef typename make_unsigned<charT>::type uchar_type;
        result2.reserve(result.size() * 2 + 2);

        for (unsigned i = 0; i < result.size(); ++i)
        {
            if (static_cast<uchar_type>(result[i]) == (std::numeric_limits<uchar_type>::max)())
            {
                result2.append(1, charT((std::numeric_limits<uchar_type>::max)())).append(1, charT('b'));
            }

            else
            {
                result2.append(1, static_cast<charT>(1 + static_cast<uchar_type>(result[i]))).append(1, charT('b') - 1);
            }
        }

        BOOST_REGEX_ASSERT(std::find(result2.begin(), result2.end(), charT(0)) == result2.end());
#ifndef BOOST_NO_EXCEPTIONS
    }

    catch (...)
    {
    }

#endif
    return result2;
}

template <class charT>
typename cpp_regex_traits_implementation<charT>::string_type
cpp_regex_traits_implementation<charT>::lookup_collatename(const charT* p1, const charT* p2) const
{
    typedef typename std::map<string_type, string_type>::const_iterator iter_type;

    if (!m_custom_collate_names.empty())
    {
        iter_type pos = m_custom_collate_names.find(string_type(p1, p2));

        if (pos != m_custom_collate_names.end())
        {
            return pos->second;
        }
    }

#if !defined(BOOST_NO_TEMPLATED_ITERATOR_CONSTRUCTORS)\
               && !BOOST_WORKAROUND(BOOST_BORLANDC, <= 0x0551)
    std::string name(p1, p2);
#else
    std::string name;
    const charT* p0 = p1;

    while (p0 != p2)
    {
        name.append(1, char(*p0++));
    }

#endif
    name = lookup_default_collate_name(name);
#if !defined(BOOST_NO_TEMPLATED_ITERATOR_CONSTRUCTORS)\
               && !BOOST_WORKAROUND(BOOST_BORLANDC, <= 0x0551)

    if (!name.empty())
    {
        return string_type(name.begin(), name.end());
    }

#else

    if (!name.empty())
    {
        string_type result;
        typedef std::string::const_iterator iter;
        iter b = name.begin();
        iter e = name.end();

        while (b != e)
        {
            result.append(1, charT(*b++));
        }

        return result;
    }

#endif

    if (p2 - p1 == 1)
    {
        return string_type(1, *p1);
    }

    return string_type();
}

template <class charT>
void
cpp_regex_traits_implementation<charT>::init()
{
#ifndef BOOST_NO_STD_MESSAGES
#ifndef __IBMCPP__
    typename std::messages<charT>::catalog cat = static_cast<std::messages<char>::catalog>(-1);
#else
    typename std::messages<charT>::catalog cat = reinterpret_cast<std::messages<char>::catalog>(-1);
#endif
    std::string cat_name(cpp_regex_traits<charT>::get_catalog_name());

    if ((!cat_name.empty()) && (this->m_pmessages != 0))
    {
        cat = this->m_pmessages->open(
                  cat_name,
                  this->m_locale);

        if ((int)cat < 0)
        {
            std::string m("Unable to open message catalog: ");
            std::runtime_error err(m + cat_name);
            boost::BOOST_REGEX_DETAIL_NS::raise_runtime_error(err);
        }
    }

    //
    // if we have a valid catalog then load our messages:
    //
    if ((int)cat >= 0)
    {
        //
        // Error messages:
        //
        for (boost::regex_constants::error_type i = static_cast<boost::regex_constants::error_type>(0);
                i <= boost::regex_constants::error_unknown;
                i = static_cast<boost::regex_constants::error_type>(i + 1))
        {
            const char* p = get_default_error_string(i);
            string_type default_message;

            while (*p)
            {
                default_message.append(1, this->m_pctype->widen(*p));
                ++p;
            }

            string_type s = this->m_pmessages->get(cat, 0, i+200, default_message);
            std::string result;

            for (std::string::size_type j = 0; j < s.size(); ++j)
            {
                result.append(1, this->m_pctype->narrow(s[j], 0));
            }

            m_error_strings[i] = result;
        }

        //
        // Custom class names:
        //
#ifndef BOOST_REGEX_BUGGY_CTYPE_FACET
        static const char_class_type masks[16] =
        {
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::alnum),
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::alpha),
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::cntrl),
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::digit),
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::graph),
            cpp_regex_traits_implementation<charT>::mask_horizontal,
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::lower),
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::print),
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::punct),
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::space),
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::upper),
            cpp_regex_traits_implementation<charT>::mask_vertical,
            static_cast<unsigned_native_mask_type>(std::ctype<charT>::xdigit),
            cpp_regex_traits_implementation<charT>::mask_blank,
            cpp_regex_traits_implementation<charT>::mask_word,
            cpp_regex_traits_implementation<charT>::mask_unicode,
        };
#else
        static const char_class_type masks[16] =
        {
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_alnum,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_alpha,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_cntrl,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_digit,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_graph,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_horizontal_space,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_lower,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_print,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_punct,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_space,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_upper,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_vertical_space,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_xdigit,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_blank,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_word,
            ::boost::BOOST_REGEX_DETAIL_NS::char_class_unicode,
        };
#endif
        static const string_type null_string;

        for (unsigned int j = 0; j <= 13; ++j)
        {
            string_type s(this->m_pmessages->get(cat, 0, j+300, null_string));

            if (!s.empty())
            {
                this->m_custom_class_names[s] = masks[j];
            }
        }
    }

#endif
    //
    // get the collation format used by m_pcollate:
    //
    m_collate_type = BOOST_REGEX_DETAIL_NS::find_sort_syntax(this, &m_collate_delim);
}

template <class charT>
typename cpp_regex_traits_implementation<charT>::char_class_type
cpp_regex_traits_implementation<charT>::lookup_classname_imp(const charT* p1, const charT* p2) const
{
#ifndef BOOST_REGEX_BUGGY_CTYPE_FACET
    static const char_class_type masks[22] =
    {
        0,
        static_cast<unsigned_native_mask_type>(std::ctype<char>::alnum),
        static_cast<unsigned_native_mask_type>(std::ctype<char>::alpha),
        cpp_regex_traits_implementation<charT>::mask_blank,
        static_cast<unsigned_native_mask_type>(std::ctype<char>::cntrl),
        static_cast<unsigned_native_mask_type>(std::ctype<char>::digit),
        static_cast<unsigned_native_mask_type>(std::ctype<char>::digit),
        static_cast<unsigned_native_mask_type>(std::ctype<char>::graph),
        cpp_regex_traits_implementation<charT>::mask_horizontal,
        static_cast<unsigned_native_mask_type>(std::ctype<char>::lower),
        static_cast<unsigned_native_mask_type>(std::ctype<char>::lower),
        static_cast<unsigned_native_mask_type>(std::ctype<char>::print),
        static_cast<unsigned_native_mask_type>(std::ctype<char>::punct),
        static_cast<unsigned_native_mask_type>(std::ctype<char>::space),
        static_cast<unsigned_native_mask_type>(std::ctype<char>::space),
        static_cast<unsigned_native_mask_type>(std::ctype<char>::upper),
        cpp_regex_traits_implementation<charT>::mask_unicode,
        static_cast<unsigned_native_mask_type>(std::ctype<char>::upper),
        cpp_regex_traits_implementation<charT>::mask_vertical,
        static_cast<unsigned_native_mask_type>(std::ctype<char>::alnum) | cpp_regex_traits_implementation<charT>::mask_word,
        static_cast<unsigned_native_mask_type>(std::ctype<char>::alnum) | cpp_regex_traits_implementation<charT>::mask_word,
        static_cast<unsigned_native_mask_type>(std::ctype<char>::xdigit),
    };
#else
    static const char_class_type masks[22] =
    {
        0,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_alnum,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_alpha,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_blank,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_cntrl,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_digit,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_digit,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_graph,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_horizontal_space,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_lower,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_lower,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_print,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_punct,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_space,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_space,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_upper,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_unicode,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_upper,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_vertical_space,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_alnum | ::boost::BOOST_REGEX_DETAIL_NS::char_class_word,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_alnum | ::boost::BOOST_REGEX_DETAIL_NS::char_class_word,
        ::boost::BOOST_REGEX_DETAIL_NS::char_class_xdigit,
    };
#endif

    if (!m_custom_class_names.empty())
    {
        typedef typename std::map<std::basic_string<charT>, char_class_type>::const_iterator map_iter;
        map_iter pos = m_custom_class_names.find(string_type(p1, p2));

        if (pos != m_custom_class_names.end())
        {
            return pos->second;
        }
    }

    std::size_t state_id = 1 + BOOST_REGEX_DETAIL_NS::get_default_class_id(p1, p2);
    BOOST_REGEX_ASSERT(state_id < sizeof(masks) / sizeof(masks[0]));
    return masks[state_id];
}

#ifdef BOOST_REGEX_BUGGY_CTYPE_FACET
template <class charT>
bool
cpp_regex_traits_implementation<charT>::isctype(const charT c, char_class_type mask) const
{
    return
        ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_space) && (this->m_pctype->is(std::ctype<charT>::space, c)))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_print) && (this->m_pctype->is(std::ctype<charT>::print, c)))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_cntrl) && (this->m_pctype->is(std::ctype<charT>::cntrl, c)))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_upper) && (this->m_pctype->is(std::ctype<charT>::upper, c)))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_lower) && (this->m_pctype->is(std::ctype<charT>::lower, c)))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_alpha) && (this->m_pctype->is(std::ctype<charT>::alpha, c)))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_digit) && (this->m_pctype->is(std::ctype<charT>::digit, c)))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_punct) && (this->m_pctype->is(std::ctype<charT>::punct, c)))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_xdigit) && (this->m_pctype->is(std::ctype<charT>::xdigit, c)))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_blank) && (this->m_pctype->is(std::ctype<charT>::space, c)) && !::boost::BOOST_REGEX_DETAIL_NS::is_separator(c))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_word) && (c == '_'))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_unicode) && ::boost::BOOST_REGEX_DETAIL_NS::is_extended(c))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_vertical_space) && (is_separator(c) || (c == '\v')))
        || ((mask & ::boost::BOOST_REGEX_DETAIL_NS::char_class_horizontal_space) && this->m_pctype->is(std::ctype<charT>::space, c) && !(is_separator(c) || (c == '\v')));
}
#endif

template <class charT>
inline boost::shared_ptr<const cpp_regex_traits_implementation<charT> >
create_cpp_regex_traits(const std::locale& l)
{
    cpp_regex_traits_base<charT> key(l);
    return ::boost::object_cache<cpp_regex_traits_base<charT>, cpp_regex_traits_implementation<charT> >::get(key, 5);
}

} // BOOST_REGEX_DETAIL_NS

template <class charT>
class cpp_regex_traits
{
  private:
    typedef std::ctype<charT>            ctype_type;
  public:
    typedef charT                        char_type;
    typedef std::size_t                  size_type;
    typedef std::basic_string<char_type> string_type;
    typedef std::locale                  locale_type;
    typedef boost::uint_least32_t        char_class_type;

    struct boost_extensions_tag {};

    cpp_regex_traits()
        : m_pimpl(BOOST_REGEX_DETAIL_NS::create_cpp_regex_traits<charT>(std::locale()))
    { }
    static size_type
    length(const char_type* p)
    {
        return std::char_traits<charT>::length(p);
    }
    regex_constants::syntax_type
    syntax_type(charT c)const
    {
        return m_pimpl->syntax_type(c);
    }
    regex_constants::escape_syntax_type
    escape_syntax_type(charT c) const
    {
        return m_pimpl->escape_syntax_type(c);
    }
    charT
    translate(charT c) const
    {
        return c;
    }
    charT
    translate_nocase(charT c) const
    {
        return m_pimpl->m_pctype->tolower(c);
    }
    charT
    translate(charT c, bool icase) const
    {
        return icase ? m_pimpl->m_pctype->tolower(c) : c;
    }
    charT
    tolower(charT c) const
    {
        return m_pimpl->m_pctype->tolower(c);
    }
    charT
    toupper(charT c) const
    {
        return m_pimpl->m_pctype->toupper(c);
    }
    string_type
    transform(const charT* p1, const charT* p2) const
    {
        return m_pimpl->transform(p1, p2);
    }
    string_type
    transform_primary(const charT* p1, const charT* p2) const
    {
        return m_pimpl->transform_primary(p1, p2);
    }
    char_class_type
    lookup_classname(const charT* p1, const charT* p2) const
    {
        return m_pimpl->lookup_classname(p1, p2);
    }
    string_type
    lookup_collatename(const charT* p1, const charT* p2) const
    {
        return m_pimpl->lookup_collatename(p1, p2);
    }
    bool
    isctype(charT c, char_class_type f) const
    {
#ifndef BOOST_REGEX_BUGGY_CTYPE_FACET
        typedef typename std::ctype<charT>::mask ctype_mask;

        static const ctype_mask mask_base =
            static_cast<ctype_mask>(
                std::ctype<charT>::alnum
                | std::ctype<charT>::alpha
                | std::ctype<charT>::cntrl
                | std::ctype<charT>::digit
                | std::ctype<charT>::graph
                | std::ctype<charT>::lower
                | std::ctype<charT>::print
                | std::ctype<charT>::punct
                | std::ctype<charT>::space
                | std::ctype<charT>::upper
                | std::ctype<charT>::xdigit);

        if ((f & mask_base)
                && (m_pimpl->m_pctype->is(
                        static_cast<ctype_mask>(f & mask_base), c)))
        {
            return true;
        }

        else if ((f & BOOST_REGEX_DETAIL_NS::cpp_regex_traits_implementation<charT>::mask_unicode) && BOOST_REGEX_DETAIL_NS::is_extended(c))
        {
            return true;
        }

        else if ((f & BOOST_REGEX_DETAIL_NS::cpp_regex_traits_implementation<charT>::mask_word) && (c == '_'))
        {
            return true;
        }

        else if ((f & BOOST_REGEX_DETAIL_NS::cpp_regex_traits_implementation<charT>::mask_blank)
                 && m_pimpl->m_pctype->is(std::ctype<charT>::space, c)
                 && !BOOST_REGEX_DETAIL_NS::is_separator(c))
        {
            return true;
        }

        else if ((f & BOOST_REGEX_DETAIL_NS::cpp_regex_traits_implementation<charT>::mask_vertical)
                 && (::boost::BOOST_REGEX_DETAIL_NS::is_separator(c) || (c == '\v')))
        {
            return true;
        }

        else if ((f & BOOST_REGEX_DETAIL_NS::cpp_regex_traits_implementation<charT>::mask_horizontal)
                 && this->isctype(c, std::ctype<charT>::space) && !this->isctype(c, BOOST_REGEX_DETAIL_NS::cpp_regex_traits_implementation<charT>::mask_vertical))
        {
            return true;
        }

#ifdef __CYGWIN__
        //
        // Cygwin has a buggy ctype facet, see https://www.cygwin.com/ml/cygwin/2012-08/msg00178.html:
        //
        else if ((f & std::ctype<charT>::xdigit) == std::ctype<charT>::xdigit)
        {
            if ((c >= 'a') && (c <= 'f'))
            {
                return true;
            }

            if ((c >= 'A') && (c <= 'F'))
            {
                return true;
            }
        }

#endif
        return false;
#else
        return m_pimpl->isctype(c, f);
#endif
    }
    boost::intmax_t
    toi(const charT*& p1, const charT* p2, int radix)const;
    int
    value(charT c, int radix)const
    {
        const charT* pc = &c;
        return (int)toi(pc, pc + 1, radix);
    }
    locale_type
    imbue(locale_type l)
    {
        std::locale result(getloc());
        m_pimpl = BOOST_REGEX_DETAIL_NS::create_cpp_regex_traits<charT>(l);
        return result;
    }
    locale_type
    getloc()const
    {
        return m_pimpl->m_locale;
    }
    std::string
    error_string(regex_constants::error_type n) const
    {
        return m_pimpl->error_string(n);
    }

    //
    // extension:
    // set the name of the message catalog in use (defaults to "boost_regex").
    //
    static std::string
    catalog_name(const std::string& name);
    static std::string
    get_catalog_name();

  private:
    boost::shared_ptr<const BOOST_REGEX_DETAIL_NS::cpp_regex_traits_implementation<charT> > m_pimpl;
    //
    // catalog name handler:
    //
    static std::string&
    get_catalog_name_inst();

#ifdef BOOST_HAS_THREADS
    static static_mutex&
    get_mutex_inst();
#endif
};

template <class charT>
boost::intmax_t
cpp_regex_traits<charT>::toi(const charT*& first, const charT* last, int radix)const
{
    BOOST_REGEX_DETAIL_NS::parser_buf<charT>   sbuf;            // buffer for parsing numbers.
    std::basic_istream<charT>      is(&sbuf);       // stream for parsing numbers.

    // we do NOT want to parse any thousands separators inside the stream:
    last = std::find(first, last, BOOST_USE_FACET(std::numpunct<charT>, is.getloc()).thousands_sep());

    sbuf.pubsetbuf(const_cast<charT*>(static_cast<const charT*>(first)), static_cast<std::streamsize>(last-first));
    is.clear();

    if (std::abs(radix) == 16)
    {
        is >> std::hex;
    }

    else if (std::abs(radix) == 8)
    {
        is >> std::oct;
    }

    else
    {
        is >> std::dec;
    }

    boost::intmax_t val;

    if (is >> val)
    {
        first = first + ((last - first) - sbuf.in_avail());
        return val;
    }

    else
    {
        return -1;
    }
}

template <class charT>
std::string
cpp_regex_traits<charT>::catalog_name(const std::string& name)
{
#ifdef BOOST_HAS_THREADS
    static_mutex::scoped_lock lk(get_mutex_inst());
#endif
    std::string result(get_catalog_name_inst());
    get_catalog_name_inst() = name;
    return result;
}

template <class charT>
std::string&
cpp_regex_traits<charT>::get_catalog_name_inst()
{
    static std::string s_name;
    return s_name;
}

template <class charT>
std::string
cpp_regex_traits<charT>::get_catalog_name()
{
#ifdef BOOST_HAS_THREADS
    static_mutex::scoped_lock lk(get_mutex_inst());
#endif
    std::string result(get_catalog_name_inst());
    return result;
}

#ifdef BOOST_HAS_THREADS
template <class charT>
static_mutex&
cpp_regex_traits<charT>::get_mutex_inst()
{
    static static_mutex s_mutex = BOOST_STATIC_MUTEX_INIT;
    return s_mutex;
}
#endif

namespace BOOST_REGEX_DETAIL_NS {

inline void
cpp_regex_traits_char_layer<char>::init()
{
    // we need to start by initialising our syntax map so we know which
    // character is used for which purpose:
    std::memset(m_char_map, 0, sizeof(m_char_map));
#ifndef BOOST_NO_STD_MESSAGES
#ifndef __IBMCPP__
    std::messages<char>::catalog cat = static_cast<std::messages<char>::catalog>(-1);
#else
    std::messages<char>::catalog cat = reinterpret_cast<std::messages<char>::catalog>(-1);
#endif
    std::string cat_name(cpp_regex_traits<char>::get_catalog_name());

    if ((!cat_name.empty()) && (m_pmessages != 0))
    {
        cat = this->m_pmessages->open(
                  cat_name,
                  this->m_locale);

        if ((int)cat < 0)
        {
            std::string m("Unable to open message catalog: ");
            std::runtime_error err(m + cat_name);
            boost::BOOST_REGEX_DETAIL_NS::raise_runtime_error(err);
        }
    }

    //
    // if we have a valid catalog then load our messages:
    //
    if ((int)cat >= 0)
    {
#ifndef BOOST_NO_EXCEPTIONS

        try
        {
#endif

            for (regex_constants::syntax_type i = 1; i < regex_constants::syntax_max; ++i)
            {
                string_type mss = this->m_pmessages->get(cat, 0, i, get_default_syntax(i));

                for (string_type::size_type j = 0; j < mss.size(); ++j)
                {
                    m_char_map[static_cast<unsigned char>(mss[j])] = i;
                }
            }

            this->m_pmessages->close(cat);
#ifndef BOOST_NO_EXCEPTIONS
        }

        catch (...)
        {
            this->m_pmessages->close(cat);
            throw;
        }

#endif
    }

    else
    {
#endif

        for (regex_constants::syntax_type j = 1; j < regex_constants::syntax_max; ++j)
        {
            const char* ptr = get_default_syntax(j);

            while (ptr && *ptr)
            {
                m_char_map[static_cast<unsigned char>(*ptr)] = j;
                ++ptr;
            }
        }

#ifndef BOOST_NO_STD_MESSAGES
    }

#endif
    //
    // finish off by calculating our escape types:
    //
    unsigned char i = 'A';

    do
    {
        if (m_char_map[i] == 0)
        {
            if (this->m_pctype->is(std::ctype_base::lower, i))
            {
                m_char_map[i] = regex_constants::escape_type_class;
            }

            else if (this->m_pctype->is(std::ctype_base::upper, i))
            {
                m_char_map[i] = regex_constants::escape_type_not_class;
            }
        }
    }
    while (0xFF != i++);
}

} // namespace detail

} // boost

#ifdef BOOST_MSVC
#pragma warning(pop)
#endif

#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable: 4103)
#endif
#ifdef BOOST_HAS_ABI_HEADERS
#  include BOOST_ABI_SUFFIX
#endif
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif

#endif

#endif
