boost/boost/regex/v4/regex_iterator.hpp

   1 /*
   2  *
   3  * Copyright (c) 2003
   4  * John Maddock
   5  *
   6  * Use, modification and distribution are subject to the
   7  * Boost Software License, Version 1.0. (See accompanying file
   8  * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9  *
  10  */
  11
  12  /*
  13   *   LOCATION:    see http://www.boost.org for most recent version.
  14   *   FILE         regex_iterator.hpp
  15   *   VERSION      see <boost/version.hpp>
  16   *   DESCRIPTION: Provides regex_iterator implementation.
  17   */
  18
  19 #ifndef BOOST_REGEX_V4_REGEX_ITERATOR_HPP
  20 #define BOOST_REGEX_V4_REGEX_ITERATOR_HPP
  21
  22 #include <boost/shared_ptr.hpp>
  23
  24 namespace boost{
  25
  26 #ifdef BOOST_HAS_ABI_HEADERS
  27 #  include BOOST_ABI_PREFIX
  28 #endif
  29
  30 template <class BidirectionalIterator,
  31           class charT,
  32           class traits>
  33 class regex_iterator_implementation
  34 {
  35    typedef basic_regex<charT, traits> regex_type;
  36
  37    match_results<BidirectionalIterator> what;  // current match
  38    BidirectionalIterator                base;  // start of sequence
  39    BidirectionalIterator                end;   // end of sequence
  40    const regex_type                     re;   // the expression
  41    match_flag_type                      flags; // flags for matching
  42
  43 public:
  44    regex_iterator_implementation(const regex_type* p, BidirectionalIterator last, match_flag_type f)
  45       : base(), end(last), re(*p), flags(f){}
  46    bool init(BidirectionalIterator first)
  47    {
  48       base = first;
  49       return regex_search(first, end, what, re, flags);
  50    }
  51    bool compare(const regex_iterator_implementation& that)
  52    {
  53       if(this == &that) return true;
  54       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);
  55    }
  56    const match_results<BidirectionalIterator>& get()
  57    { return what; }
  58    bool next()
  59    {
  60       //if(what.prefix().first != what[0].second)
  61       //   flags |= match_prev_avail;
  62       BidirectionalIterator next_start = what[0].second;
  63       match_flag_type f(flags);
  64       if(!what.length())
  65          f |= regex_constants::match_not_initial_null;
  66       //if(base != next_start)
  67       //   f |= regex_constants::match_not_bob;
  68       bool result = regex_search(next_start, end, what, re, f, base);
  69       if(result)
  70          what.set_base(base);
  71       return result;
  72    }
  73 private:
  74    regex_iterator_implementation& operator=(const regex_iterator_implementation&);
  75 };
  76
  77 template <class BidirectionalIterator,
  78           class charT = BOOST_DEDUCED_TYPENAME re_detail::regex_iterator_traits<BidirectionalIterator>::value_type,
  79           class traits = regex_traits<charT> >
  80 class regex_iterator
  81 #ifndef BOOST_NO_STD_ITERATOR
  82    : public std::iterator<
  83          std::forward_iterator_tag,
  84          match_results<BidirectionalIterator>,
  85          typename re_detail::regex_iterator_traits<BidirectionalIterator>::difference_type,
  86          const match_results<BidirectionalIterator>*,
  87          const match_results<BidirectionalIterator>& >
  88 #endif
  89 {
  90 private:
  91    typedef regex_iterator_implementation<BidirectionalIterator, charT, traits> impl;
  92    typedef shared_ptr<impl> pimpl;
  93 public:
  94    typedef          basic_regex<charT, traits>                   regex_type;
  95    typedef          match_results<BidirectionalIterator>                    value_type;
  96    typedef typename re_detail::regex_iterator_traits<BidirectionalIterator>::difference_type
  97                                                                             difference_type;
  98    typedef          const value_type*                                       pointer;
  99    typedef          const value_type&                                       reference;
 100    typedef          std::forward_iterator_tag                               iterator_category;
 101
 102    regex_iterator(){}
 103    regex_iterator(BidirectionalIterator a, BidirectionalIterator b,
 104                   const regex_type& re,
 105                   match_flag_type m = match_default)
 106                   : pdata(new impl(&re, b, m))
 107    {
 108       if(!pdata->init(a))
 109       {
 110          pdata.reset();
 111       }
 112    }
 113    regex_iterator(const regex_iterator& that)
 114       : pdata(that.pdata) {}
 115    regex_iterator& operator=(const regex_iterator& that)
 116    {
 117       pdata = that.pdata;
 118       return *this;
 119    }
 120    bool operator==(const regex_iterator& that)const
 121    {
 122       if((pdata.get() == 0) || (that.pdata.get() == 0))
 123          return pdata.get() == that.pdata.get();
 124       return pdata->compare(*(that.pdata.get()));
 125    }
 126    bool operator!=(const regex_iterator& that)const
 127    { return !(*this == that); }
 128    const value_type& operator*()const
 129    { return pdata->get(); }
 130    const value_type* operator->()const
 131    { return &(pdata->get()); }
 132    regex_iterator& operator++()
 133    {
 134       cow();
 135       if(0 == pdata->next())
 136       {
 137          pdata.reset();
 138       }
 139       return *this;
 140    }
 141    regex_iterator operator++(int)
 142    {
 143       regex_iterator result(*this);
 144       ++(*this);
 145       return result;
 146    }
 147 private:
 148
 149    pimpl pdata;
 150
 151    void cow()
 152    {
 153       // copy-on-write
 154       if(pdata.get() && !pdata.unique())
 155       {
 156          pdata.reset(new impl(*(pdata.get())));
 157       }
 158    }
 159 };
 160
 161 typedef regex_iterator<const char*> cregex_iterator;
 162 typedef regex_iterator<std::string::const_iterator> sregex_iterator;
 163 #ifndef BOOST_NO_WREGEX
 164 typedef regex_iterator<const wchar_t*> wcregex_iterator;
 165 typedef regex_iterator<std::wstring::const_iterator> wsregex_iterator;
 166 #endif
 167
 168 // make_regex_iterator:
 169 template <class charT, class traits>
 170 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)
 171 {
 172    return regex_iterator<const charT*, charT, traits>(p, p+traits::length(p), e, m);
 173 }
 174 template <class charT, class traits, class ST, class SA>
 175 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)
 176 {
 177    return regex_iterator<typename std::basic_string<charT, ST, SA>::const_iterator, charT, traits>(p.begin(), p.end(), e, m);
 178 }
 179
 180 #ifdef BOOST_HAS_ABI_HEADERS
 181 #  include BOOST_ABI_SUFFIX
 182 #endif
 183
 184 } // namespace boost
 185
 186 #endif // BOOST_REGEX_V4_REGEX_ITERATOR_HPP
 187