_istream.c

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      }
    } // Close the while loop.
  }
  _STLP_CATCH_ALL {
    __that->_M_handle_exception(ios_base::badbit);
    return __n;
  }

  if (__at_eof)
    __that->setstate(__set_failbit ? ios_base::eofbit | ios_base::failbit
                                   : ios_base::eofbit);

  if (__done)
    return __n;

  // If execution has reached this point, then we have an empty buffer but
  // we have not reached eof.  What that means is that the streambuf has
  // decided to switch from buffered to unbuffered input.  We switch to
  // to _M_ignore_unbuffered.

  return __n + _M_ignore_unbuffered(__that,  __buf, _Num, __max_chars,
                                    __is_delim, __extract_delim, __set_failbit);
}


template <class _CharT, class _Traits>
basic_istream<_CharT, _Traits>&
basic_istream<_CharT, _Traits>::ignore(streamsize __n) {
  sentry __sentry(*this, _No_Skip_WS());
  this->_M_gcount = 0;

  if (__sentry) {
    basic_streambuf<_CharT, _Traits>* __buf = this->rdbuf();
    typedef _STLP_PRIV _Constant_unary_fun<bool, int_type> _Const_bool;
    typedef _STLP_PRIV _Constant_binary_fun<streamsize, streamsize, streamsize> _Const_streamsize;
    const streamsize __maxss = (numeric_limits<streamsize>::max)();

    if (__n == (numeric_limits<int>::max)()) {
      if (__buf->gptr() != __buf->egptr())
        _M_gcount = _M_ignore_buffered(this,  __buf,
                                       __maxss, _Const_streamsize(__maxss),
                                       _Const_bool(false),
                                       _STLP_PRIV _Project2nd<const _CharT*, const _CharT*>(),
                                       false, false);
      else
        _M_gcount = _M_ignore_unbuffered(this,  __buf,
                                         __maxss, _Const_streamsize(__maxss),
                                         _Const_bool(false), false, false);
    }
    else {
      if (__buf->gptr() != __buf->egptr())
        _M_gcount = _M_ignore_buffered(this,  __buf,
                                       __n, minus<streamsize>(),
                                       _Const_bool(false),
                                       _STLP_PRIV _Project2nd<const _CharT*, const _CharT*>(),
                                       false, false);
      else
        _M_gcount = _M_ignore_unbuffered(this,  __buf, __n, minus<streamsize>(),
                                         _Const_bool(false), false, false);
    }
  }

  return *this;
}

template <class _CharT, class _Traits>
basic_istream<_CharT, _Traits>&
basic_istream<_CharT, _Traits>::ignore(streamsize __n, int_type __delim) {
  sentry __sentry(*this, _No_Skip_WS());
  this->_M_gcount = 0;

  if (__sentry) {
    basic_streambuf<_CharT, _Traits>* __buf = this->rdbuf();
    typedef _STLP_PRIV _Constant_unary_fun<bool, int_type> _Const_bool;
    typedef _STLP_PRIV _Constant_binary_fun<streamsize, streamsize, streamsize>
      _Const_streamsize;
    const streamsize __maxss = (numeric_limits<streamsize>::max)();

    if (__n == (numeric_limits<int>::max)()) {
      if (__buf->gptr() != __buf->egptr())
        _M_gcount = _M_ignore_buffered(this,  __buf,
                                       __maxss, _Const_streamsize(__maxss),
                                       _STLP_PRIV _Eq_int_bound<_Traits>(__delim),
                                       _STLP_PRIV _Scan_for_int_val<_Traits>(__delim),
                                       true, false);
      else
        _M_gcount = _M_ignore_unbuffered(this,  __buf,
                                         __maxss, _Const_streamsize(__maxss),
                                         _STLP_PRIV _Eq_int_bound<_Traits>(__delim),
                                         true, false);
    }
    else {
      if (__buf->gptr() != __buf->egptr())
        _M_gcount = _M_ignore_buffered(this,  __buf,
                                       __n, minus<streamsize>(),
                                       _STLP_PRIV _Eq_int_bound<_Traits>(__delim),
                                       _STLP_PRIV _Scan_for_int_val<_Traits>(__delim),
                                       true, false);
      else
        _M_gcount = _M_ignore_unbuffered(this,  __buf, __n, minus<streamsize>(),
                                         _STLP_PRIV _Eq_int_bound<_Traits>(__delim),
                                         true, false);
    }
  }

  return *this;
}

// This member function does not construct a sentry object, because
// it is called from sentry's constructor.
template <class _CharT, class _Traits>
void basic_istream<_CharT, _Traits>::_M_skip_whitespace(bool __set_failbit) {
  basic_streambuf<_CharT, _Traits>* __buf = this->rdbuf();
  if (!__buf)
    this->setstate(ios_base::badbit);
  else if (__buf->gptr() != __buf->egptr())
    _M_ignore_buffered(this,  __buf,
                       _STLP_PRIV _Is_not_wspace<_Traits>(this->_M_ctype_facet()),
                       _STLP_PRIV _Scan_for_not_wspace<_Traits>(this->_M_ctype_facet()),
                       false, __set_failbit);
  else
    _M_ignore_unbuffered(this,  __buf,
                         _STLP_PRIV _Is_not_wspace<_Traits>(this->_M_ctype_facet()),
                         false, __set_failbit);
}


// This is a very simple loop that reads characters from __src and puts
// them into __dest.  It looks complicated because of the (standard-
// mandated) exception handling policy.
//
// We stop when we get an exception, when we fail to insert into the
// output streambuf, or when __is_delim is true.

_STLP_MOVE_TO_PRIV_NAMESPACE

template < class _CharT, class _Traits, class _Is_Delim>
streamsize _STLP_CALL
__copy_unbuffered(basic_istream<_CharT, _Traits>* __that, basic_streambuf<_CharT, _Traits>* __src,
                  basic_streambuf<_CharT, _Traits>* __dest,
                  _Is_Delim __is_delim,
                  bool __extract_delim, bool __rethrow) {
  streamsize __extracted = 0;
  ios_base::iostate __status = 0;
  typedef typename basic_istream<_CharT, _Traits>::int_type int_type;
  int_type __c;

  _STLP_TRY {
    for (;;) {
      // Get a character. If there's an exception, catch and (maybe) rethrow it.
      __c = __src->sbumpc();

      // If we failed to get a character, then quit.
      if (__that->_S_eof(__c)) {
        __status |= ios_base::eofbit;
        break;
      }
      // If it's the delimiter, then quit.
      else if (__is_delim(_Traits::to_char_type(__c))) {
        if (!__extract_delim && !__pushback(__src, _Traits::to_char_type(__c)))
          __status |= ios_base::failbit;
        break;
      }
      else {
        // Try to put the character in the output streambuf.
        bool __failed = false;
        _STLP_TRY {
          if (!__that->_S_eof(__dest->sputc(_Traits::to_char_type(__c))))
            ++__extracted;
          else
            __failed = true;
        }
        _STLP_CATCH_ALL {
          __failed = true;
        }

        // If we failed to put the character in the output streambuf, then
        // try to push it back to the input streambuf.
        if (__failed && !__pushback(__src, _Traits::to_char_type(__c)))
          __status |= ios_base::failbit;

        // fbp : avoiding infinite loop in io-27-6-1-2-3.exp
        if (__failed)
          break;
      }

    } /* for (;;) */

  }
  // fbp : this try/catch moved here in reasonable assumption
  // __is_delim never throw (__pushback is guaranteed not to)
  _STLP_CATCH_ALL {
    // See 27.6.1.2.3, paragraph 13.
    if (__rethrow && __extracted == 0)
      __that->_M_handle_exception(ios_base::failbit);
  }
  __that->setstate(__status);
  return __extracted;
}

// Buffered copying from one streambuf to another.  We copy the characters
// in chunks, rather than one at a time.  We still have to worry about all
// of the error conditions we checked in __copy_unbuffered, plus one more:
// the streambuf might decide to switch from a buffered to an unbuffered mode.

template < class _CharT, class _Traits, class _Is_Delim, class _Scan_Delim>
streamsize _STLP_CALL
__copy_buffered(basic_istream<_CharT, _Traits>* __that, basic_streambuf<_CharT, _Traits>* __src,
                basic_streambuf<_CharT, _Traits>* __dest,
                _Scan_Delim __scan_delim, _Is_Delim __is_delim,
                bool __extract_delim, bool __rethrow) {
  streamsize __extracted = 0;
  ios_base::iostate __status = 0;
  typedef typename basic_istream<_CharT, _Traits>::int_type int_type;
  //Borland compiler generates a warning if assignment because value is never used:
  int_type __c /*= _Traits::eof()*/;
  _CharT* __first = __src->_M_gptr();
  ptrdiff_t __avail = __src->_M_egptr() - __first;
  // fbp : introduced to move catch/try blocks out of the loop
  bool __do_handle_exceptions = false;

  _STLP_TRY {
    for (;;) {
      const _CharT* __last = __scan_delim(__first, __src->_M_egptr());

      // Try to copy the entire input buffer to the output buffer.
      streamsize __n = __dest->sputn(__first, __extract_delim && __last != __src->_M_egptr()
                                     ? (__last - __first) + 1
                                     : (__last - __first));
      __src->_M_gbump((int)__n);
      __extracted += __n;

      // from this on, catch() will call _M_handle_exceptions()
      __do_handle_exceptions = true;

      if (__n < __avail)          // We found the delimiter, or else failed to
        break;                    // copy some characters.

      __c = __src->sgetc();

      // Three possibilities: we succeeded in refilling the buffer, or
      // we got EOF, or the streambuf has switched to unbuffered mode.
      __first = __src->_M_gptr();
      __avail = __src->_M_egptr() - __first;

      if (__avail > 0)
        {}  // dwa 1/16/00 -- suppress a Metrowerks warning
      else if (__that->_S_eof(__c)) {
        __status |= ios_base::eofbit;
        break;
      }
      else {
        return __extracted + __copy_unbuffered(__that,  __src, __dest, __is_delim,
                                                __extract_delim, __rethrow);
      }

      __do_handle_exceptions = false;
    }
  }

  _STLP_CATCH_ALL {
    // See 27.6.1.2.3, paragraph 13.
    if (__rethrow && __do_handle_exceptions &&  __extracted == 0)
      __that->_M_handle_exception(ios_base::failbit);
  }

  if (__status)
    __that->setstate(__status);   // This might throw.
  return __extracted;
}

_STLP_MOVE_TO_STD_NAMESPACE

template <class _CharT, class _Traits>
basic_istream<_CharT, _Traits>&
basic_istream<_CharT, _Traits>
  ::get(basic_streambuf<_CharT, _Traits>& __dest, _CharT __delim) {
  sentry __sentry(*this, _No_Skip_WS());
  this->_M_gcount = 0;

  if (__sentry) {
    basic_streambuf<_CharT, _Traits>* __src = this->rdbuf();

    if (__src)
      this->_M_gcount = __src->egptr() != __src->gptr()
        ? _STLP_PRIV __copy_buffered(this,  __src, &__dest,
                                     _STLP_PRIV _Scan_for_char_val<_Traits>(__delim),
                                     _STLP_PRIV _Eq_char_bound<_Traits>(__delim),
                                     false, false)
        : _STLP_PRIV __copy_unbuffered(this,  __src, &__dest,
                                       _STLP_PRIV _Eq_char_bound<_Traits>(__delim),
                                       false, false);
  }

  if (this->_M_gcount == 0)
    this->setstate(ios_base::failbit);

  return *this;
}

// Copying characters into a streambuf.
template <class _CharT, class _Traits>
basic_istream<_CharT, _Traits>&
basic_istream<_CharT, _Traits>
  ::operator>>(basic_streambuf<_CharT, _Traits>* __dest) {
  streamsize __n = 0;
  typedef typename basic_istream<_CharT, _Traits>::sentry _Sentry;
  _Sentry __sentry(*this);
  if (__sentry) {
    basic_streambuf<_CharT, _Traits>* __src = this->rdbuf();
    if (__src && __dest)
      __n = __src->egptr() != __src->gptr()
        ? _STLP_PRIV __copy_buffered(this,  __src, __dest,
                                     _STLP_PRIV _Project2nd<const _CharT*, const _CharT*>(),
                                     _STLP_PRIV _Constant_unary_fun<bool, int_type>(false),
                                     false, true)
        : _STLP_PRIV __copy_unbuffered(this,  __src, __dest,
                                       _STLP_PRIV _Constant_unary_fun<bool, int_type>(false),
                                       false, true);
  }

  if (__n == 0)
    this->setstate(ios_base::failbit);

  return *this;
}

// ----------------------------------------------------------------
// basic_iostream<> class
// ----------------------------------------------------------------

template <class _CharT, class _Traits>
basic_iostream<_CharT, _Traits>
  ::basic_iostream(basic_streambuf<_CharT, _Traits>* __buf)
    : basic_ios<_CharT, _Traits>(),
      basic_istream<_CharT, _Traits>(__buf),
      basic_ostream<_CharT, _Traits>(__buf) {
  this->init(__buf);
}

template <class _CharT, class _Traits>
basic_iostream<_CharT, _Traits>::~basic_iostream()
{}

_STLP_END_NAMESPACE

#undef __BIS_int_type__
#undef __BIS_pos_type__
#undef __BIS_off_type__

#endif /* _STLP_ISTREAM_C */

// Local Variables:
// mode:C++
// End: