ceph/src/boost/libs/config/test/boost_no_std_wstreambuf.ipp

   1 //  (C) Copyright John Maddock 2001.
   2 //  Use, modification and distribution are subject to the
   3 //  Boost Software License, Version 1.0. (See accompanying file
   4 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 //  See http://www.boost.org/libs/config for most recent version.
   7
   8 //  MACRO:         BOOST_NO_STD_WSTREAMBUF
   9 //  TITLE:         std::basic_streambuf<wchar_t>
  10 //  DESCRIPTION:   The standard library lacks std::basic_streambuf<wchar_t>.
  11
  12 #include <iostream>
  13 #include <streambuf>
  14 #include <string>
  15
  16 namespace boost_no_std_wstreambuf{
  17
  18 template <class charT,
  19           class traits = ::std::char_traits<charT> >
  20 class parser_buf : public ::std::basic_streambuf<charT, traits>
  21 {
  22    typedef ::std::basic_streambuf<charT, traits> base_type;
  23    typedef typename base_type::int_type int_type;
  24    typedef typename base_type::char_type char_type;
  25    typedef typename base_type::pos_type pos_type;
  26    typedef ::std::streamsize streamsize;
  27    typedef typename base_type::off_type off_type;
  28 public:
  29    parser_buf() : base_type() { setbuf(0, 0); }
  30    const charT* getnext() { return this->gptr(); }
  31 protected:
  32    std::basic_streambuf<charT, traits>* setbuf(char_type* s, streamsize n);
  33    typename parser_buf<charT, traits>::pos_type seekpos(pos_type sp, ::std::ios_base::openmode which);
  34    typename parser_buf<charT, traits>::pos_type seekoff(off_type off, ::std::ios_base::seekdir way, ::std::ios_base::openmode which);
  35 private:
  36    parser_buf& operator=(const parser_buf&)
  37    { return *this; };
  38    parser_buf(const parser_buf&);
  39 };
  40
  41 template<class charT, class traits>
  42 std::basic_streambuf<charT, traits>*
  43 parser_buf<charT, traits>::setbuf(char_type* s, streamsize n)
  44 {
  45    this->setg(s, s, s + n);
  46    return this;
  47 }
  48
  49 template<class charT, class traits>
  50 typename parser_buf<charT, traits>::pos_type
  51 parser_buf<charT, traits>::seekoff(off_type off, ::std::ios_base::seekdir way, ::std::ios_base::openmode which)
  52 {
  53    typedef typename parser_buf<charT, traits>::pos_type pos_type;
  54    if(which & ::std::ios_base::out)
  55       return pos_type(off_type(-1));
  56    int size = this->egptr() - this->eback();
  57    int pos = this->gptr() - this->eback();
  58    charT* g = this->eback();
  59    switch((int)way)
  60    {
  61    case ::std::ios_base::beg:
  62       if((off < 0) || (off > size))
  63          return pos_type(off_type(-1));
  64       else
  65          this->setg(g, g + off, g + size);
  66    case ::std::ios_base::end:
  67       if((off < 0) || (off > size))
  68          return pos_type(off_type(-1));
  69       else
  70          this->setg(g, g + size - off, g + size);
  71    case ::std::ios_base::cur:
  72    {
  73       int newpos = pos + off;
  74       if((newpos < 0) || (newpos > size))
  75          return pos_type(off_type(-1));
  76       else
  77          this->setg(g, g + newpos, g + size);
  78    }
  79    }
  80    return static_cast<pos_type>(this->gptr() - this->eback());
  81 }
  82
  83 template<class charT, class traits>
  84 typename parser_buf<charT, traits>::pos_type
  85 parser_buf<charT, traits>::seekpos(pos_type sp, ::std::ios_base::openmode which)
  86 {
  87    if(which & ::std::ios_base::out)
  88       return pos_type(off_type(-1));
  89    int size = this->egptr() - this->eback();
  90    charT* g = this->eback();
  91    if(off_type(sp) <= size)
  92    {
  93       this->setg(g, g + off_type(sp), g + size);
  94    }
  95    return pos_type(off_type(-1));
  96 }
  97
  98
  99 int test()
 100 {
 101    return 0;
 102 }
 103
 104 template class parser_buf<char>;
 105 template class parser_buf<wchar_t>;
 106
 107 }
 108