regex/v4/regex_iterator.hpp

0001 /*
0002  *
0003  * Copyright (c) 2003
0004  * John Maddock
0005  *
0006  * Use, modification and distribution are subject to the
0007  * Boost Software License, Version 1.0. (See accompanying file
0008  * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0009  *
0010  */
0011
0012  /*
0013   *   LOCATION:    see http://www.boost.org for most recent version.
0014   *   FILE         regex_iterator.hpp
0015   *   VERSION      see <boost/version.hpp>
0016   *   DESCRIPTION: Provides regex_iterator implementation.
0017   */
0018
0019 #ifndef BOOST_REGEX_V4_REGEX_ITERATOR_HPP
0020 #define BOOST_REGEX_V4_REGEX_ITERATOR_HPP
0021
0022 #include <boost/shared_ptr.hpp>
0023
0024 namespace boost{
0025
0026 #ifdef BOOST_MSVC
0027 #pragma warning(push)
0028 #pragma warning(disable: 4103)
0029 #endif
0030 #ifdef BOOST_HAS_ABI_HEADERS
0031 #  include BOOST_ABI_PREFIX
0032 #endif
0033 #ifdef BOOST_MSVC
0034 #pragma warning(pop)
0035 #endif
0036
0037 template <class BidirectionalIterator,
0038           class charT,
0039           class traits>
0040 class regex_iterator_implementation
0041 {
0042    typedef basic_regex<charT, traits> regex_type;
0043
0044    match_results<BidirectionalIterator> what;  // current match
0045    BidirectionalIterator                base;  // start of sequence
0046    BidirectionalIterator                end;   // end of sequence
0047    const regex_type                     re;   // the expression
0048    match_flag_type                      flags; // flags for matching
0049
0050 public:
0051    regex_iterator_implementation(const regex_type* p, BidirectionalIterator last, match_flag_type f)
0052       : base(), end(last), re(*p), flags(f){}
0053    regex_iterator_implementation(const regex_iterator_implementation& other)
0054       :what(other.what), base(other.base), end(other.end), re(other.re), flags(other.flags){}
0055    bool init(BidirectionalIterator first)
0056    {
0057       base = first;
0058       return regex_search(first, end, what, re, flags);
0059    }
0060    bool compare(const regex_iterator_implementation& that)
0061    {
0062       if(this == &that) return true;
0063       return (&re.get_data() == &that.re.get_data()) && (end == that.end) && (flags == that.flags) && (what[0].first == that.what[0].first) && (what[0].second == that.what[0].second);
0064    }
0065    const match_results<BidirectionalIterator>& get()
0066    { return what; }
0067    bool next()
0068    {
0069       //if(what.prefix().first != what[0].second)
0070       //   flags |= match_prev_avail;
0071       BidirectionalIterator next_start = what[0].second;
0072       match_flag_type f(flags);
0073       if(!what.length() || (f & regex_constants::match_posix))
0074          f |= regex_constants::match_not_initial_null;
0075       //if(base != next_start)
0076       //   f |= regex_constants::match_not_bob;
0077       bool result = regex_search(next_start, end, what, re, f, base);
0078       if(result)
0079          what.set_base(base);
0080       return result;
0081    }
0082 private:
0083    regex_iterator_implementation& operator=(const regex_iterator_implementation&);
0084 };
0085
0086 template <class BidirectionalIterator,
0087           class charT = BOOST_DEDUCED_TYPENAME BOOST_REGEX_DETAIL_NS::regex_iterator_traits<BidirectionalIterator>::value_type,
0088           class traits = regex_traits<charT> >
0089 class regex_iterator
0090 {
0091 private:
0092    typedef regex_iterator_implementation<BidirectionalIterator, charT, traits> impl;
0093    typedef shared_ptr<impl> pimpl;
0094 public:
0095    typedef          basic_regex<charT, traits>                   regex_type;
0096    typedef          match_results<BidirectionalIterator>                    value_type;
0097    typedef typename BOOST_REGEX_DETAIL_NS::regex_iterator_traits<BidirectionalIterator>::difference_type
0098                                                                             difference_type;
0099    typedef          const value_type*                                       pointer;
0100    typedef          const value_type&                                       reference;
0101    typedef          std::forward_iterator_tag                               iterator_category;
0102
0103    regex_iterator(){}
0104    regex_iterator(BidirectionalIterator a, BidirectionalIterator b,
0105                   const regex_type& re,
0106                   match_flag_type m = match_default)
0107                   : pdata(new impl(&re, b, m))
0108    {
0109       if(!pdata->init(a))
0110       {
0111          pdata.reset();
0112       }
0113    }
0114    regex_iterator(const regex_iterator& that)
0115       : pdata(that.pdata) {}
0116    regex_iterator& operator=(const regex_iterator& that)
0117    {
0118       pdata = that.pdata;
0119       return *this;
0120    }
0121    bool operator==(const regex_iterator& that)const
0122    {
0123       if((pdata.get() == 0) || (that.pdata.get() == 0))
0124          return pdata.get() == that.pdata.get();
0125       return pdata->compare(*(that.pdata.get()));
0126    }
0127    bool operator!=(const regex_iterator& that)const
0128    { return !(*this == that); }
0129    const value_type& operator*()const
0130    { return pdata->get(); }
0131    const value_type* operator->()const
0132    { return &(pdata->get()); }
0133    regex_iterator& operator++()
0134    {
0135       cow();
0136       if(0 == pdata->next())
0137       {
0138          pdata.reset();
0139       }
0140       return *this;
0141    }
0142    regex_iterator operator++(int)
0143    {
0144       regex_iterator result(*this);
0145       ++(*this);
0146       return result;
0147    }
0148 private:
0149
0150    pimpl pdata;
0151
0152    void cow()
0153    {
0154       // copy-on-write
0155       if(pdata.get() && !pdata.unique())
0156       {
0157          pdata.reset(new impl(*(pdata.get())));
0158       }
0159    }
0160 };
0161
0162 typedef regex_iterator<const char*> cregex_iterator;
0163 typedef regex_iterator<std::string::const_iterator> sregex_iterator;
0164 #ifndef BOOST_NO_WREGEX
0165 typedef regex_iterator<const wchar_t*> wcregex_iterator;
0166 typedef regex_iterator<std::wstring::const_iterator> wsregex_iterator;
0167 #endif
0168
0169 // make_regex_iterator:
0170 template <class charT, class traits>
0171 inline regex_iterator<const charT*, charT, traits> make_regex_iterator(const charT* p, const basic_regex<charT, traits>& e, regex_constants::match_flag_type m = regex_constants::match_default)
0172 {
0173    return regex_iterator<const charT*, charT, traits>(p, p+traits::length(p), e, m);
0174 }
0175 template <class charT, class traits, class ST, class SA>
0176 inline regex_iterator<typename std::basic_string<charT, ST, SA>::const_iterator, charT, traits> make_regex_iterator(const std::basic_string<charT, ST, SA>& p, const basic_regex<charT, traits>& e, regex_constants::match_flag_type m = regex_constants::match_default)
0177 {
0178    return regex_iterator<typename std::basic_string<charT, ST, SA>::const_iterator, charT, traits>(p.begin(), p.end(), e, m);
0179 }
0180
0181 #ifdef BOOST_MSVC
0182 #pragma warning(push)
0183 #pragma warning(disable: 4103)
0184 #endif
0185 #ifdef BOOST_HAS_ABI_HEADERS
0186 #  include BOOST_ABI_SUFFIX
0187 #endif
0188 #ifdef BOOST_MSVC
0189 #pragma warning(pop)
0190 #endif
0191
0192 } // namespace boost
0193
0194 #endif // BOOST_REGEX_V4_REGEX_ITERATOR_HPP
0195