_sstream.c

symbian 上的stl_port进过编译的。

/*
 * Copyright (c) 1999
 * Silicon Graphics Computer Systems, Inc.
 *
 * Copyright (c) 1999
 * Boris Fomitchev
 *
 * This material is provided "as is", with absolutely no warranty expressed
 * or implied. Any use is at your own risk.
 *
 * Permission to use or copy this software for any purpose is hereby granted
 * without fee, provided the above notices are retained on all copies.
 * Permission to modify the code and to distribute modified code is granted,
 * provided the above notices are retained, and a notice that the code was
 * modified is included with the above copyright notice.
 *
 */

#ifndef _STLP_SSTREAM_C
#define _STLP_SSTREAM_C

#ifndef _STLP_INTERNAL_SSTREAM
#  include <stl/_sstream.h>
#endif

#if defined ( _STLP_NESTED_TYPE_PARAM_BUG )
// no wint_t is supported for this mode
#  define __BSB_int_type__ int
#  define __BSB_pos_type__ streampos
#else
#  define __BSB_int_type__ _STLP_TYPENAME_ON_RETURN_TYPE basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
#  define __BSB_pos_type__ _STLP_TYPENAME_ON_RETURN_TYPE basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
#endif

_STLP_BEGIN_NAMESPACE

//----------------------------------------------------------------------
// Non-inline stringbuf member functions.

// Constructors.  Note that the base class constructor sets all of the
// get and area pointers to null.

template <class _CharT, class _Traits, class _Alloc>
basic_stringbuf<_CharT, _Traits, _Alloc>
  ::basic_stringbuf(ios_base::openmode __mode)
    : basic_streambuf<_CharT, _Traits>(), _M_mode(__mode), _M_str()
{}

template <class _CharT, class _Traits, class _Alloc>
basic_stringbuf<_CharT, _Traits, _Alloc>
  ::basic_stringbuf(const basic_string<_CharT, _Traits, _Alloc>& __s, ios_base::openmode __mode)
    : basic_streambuf<_CharT, _Traits>(), _M_mode(__mode), _M_str(__s)
{
  _M_set_ptrs();
}

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

// Set the underlying string to a new value.
template <class _CharT, class _Traits, class _Alloc>
void
basic_stringbuf<_CharT, _Traits, _Alloc>::str(const basic_string<_CharT, _Traits, _Alloc>& __s)
{
  _M_str = __s;
  _M_set_ptrs();
}

template <class _CharT, class _Traits, class _Alloc>
void
basic_stringbuf<_CharT, _Traits, _Alloc>::_M_set_ptrs() {
  _CharT* __data_ptr = __CONST_CAST(_CharT*,_M_str.data());
  _CharT* __data_end = __data_ptr + _M_str.size();
  // The initial read position is the beginning of the string.
  if (_M_mode & ios_base::in) {
    if (_M_mode & ios_base::ate)
      this->setg(__data_ptr, __data_end, __data_end);
    else
      this->setg(__data_ptr, __data_ptr, __data_end);
  }

  // The initial write position is the beginning of the string.
  if (_M_mode & ios_base::out) {
    if (_M_mode & (ios_base::app | ios_base::ate))
      this->setp(__data_end, __data_end);
    else
      this->setp(__data_ptr, __data_end);
  }
}

// Precondition: gptr() >= egptr().  Returns a character, if one is available.
template <class _CharT, class _Traits, class _Alloc>
__BSB_int_type__
basic_stringbuf<_CharT, _Traits, _Alloc>::underflow() {
  return this->gptr() != this->egptr()
    ? _Traits::to_int_type(*this->gptr())
    : _Traits::eof();
}

// Precondition: gptr() >= egptr().
template <class _CharT, class _Traits, class _Alloc>
__BSB_int_type__
basic_stringbuf<_CharT, _Traits, _Alloc>::uflow() {
  if (this->gptr() != this->egptr()) {
    int_type __c = _Traits::to_int_type(*this->gptr());
    this->gbump(1);
    return __c;
  }
  else
    return _Traits::eof();
}

template <class _CharT, class _Traits, class _Alloc>
__BSB_int_type__
basic_stringbuf<_CharT, _Traits, _Alloc>::pbackfail(int_type __c) {
  if (this->gptr() != this->eback()) {
    if (!_Traits::eq_int_type(__c, _Traits::eof())) {
      if (_Traits::eq(_Traits::to_char_type(__c), this->gptr()[-1])) {
        this->gbump(-1);
        return __c;
      }
      else if (_M_mode & ios_base::out) {
        this->gbump(-1);
        *this->gptr() = _Traits::to_char_type(__c);
        return __c;
      }
      else
        return _Traits::eof();
    }
    else {
      this->gbump(-1);
      return _Traits::not_eof(__c);
    }
  }
  else
    return _Traits::eof();
}

template <class _CharT, class _Traits, class _Alloc>
__BSB_int_type__
basic_stringbuf<_CharT, _Traits, _Alloc>::overflow(int_type __c) {
  // fbp : reverse order of "ifs" to pass Dietmar's test.
  // Apparently, standard allows overflow with eof even for read-only streams.
  if (!_Traits::eq_int_type(__c, _Traits::eof())) {
    if (_M_mode & ios_base::out) {
      if (!(_M_mode & ios_base::in)) {
        // It's a write-only streambuf, so we can use special append buffer.
        if (this->pptr() == this->epptr())
          this->_M_append_buffer();

        if (this->pptr() != this->epptr()) {
          *this->pptr() = _Traits::to_char_type(__c);
          this->pbump(1);
          return __c;
        }
        else
          return _Traits::eof();
      }
      else {
        // We're not using a special append buffer, just the string itself.
        if (this->pptr() == this->epptr()) {
          ptrdiff_t __offset = this->gptr() - this->eback();
          _M_str.push_back(_Traits::to_char_type(__c));

          _CharT* __data_ptr = __CONST_CAST(_CharT*,_M_str.data());
          size_t __data_size = _M_str.size();

          this->setg(__data_ptr, __data_ptr + __offset, __data_ptr+__data_size);
          this->setp(__data_ptr, __data_ptr + __data_size);
          this->pbump((int)__data_size);
          return __c;
        }
        else {
          *this->pptr() = _Traits::to_char_type(__c);
          this->pbump(1);
          return __c;
        }
      }
    }
    else                          // Overflow always fails if it's read-only
      return _Traits::eof();
  }
  else                        // __c is EOF, so we don't have to do anything
    return _Traits::not_eof(__c);
}

template <class _CharT, class _Traits, class _Alloc>
streamsize
basic_stringbuf<_CharT, _Traits, _Alloc>::xsputn(const char_type* __s,
                                                 streamsize __n) {
  streamsize __nwritten = 0;

  if ((_M_mode & ios_base::out) && __n > 0) {
    // If the put pointer is somewhere in the middle of the string,
    // then overwrite instead of append.
    if (this->pbase() == _M_str.data() ) {
      ptrdiff_t __avail = _M_str.data() + _M_str.size() - this->pptr();
      if (__avail > __n) {
        _Traits::copy(this->pptr(), __s, __STATIC_CAST(size_t, __n));
        this->pbump((int)__n);
        return __n;
      }
      else {
        _Traits::copy(this->pptr(), __s, __avail);
        __nwritten += __avail;
        __n -= __avail;
        __s += __avail;
        this->setp(_M_Buf, _M_Buf + __STATIC_CAST(int,_S_BufSiz));
      }
    }

    // At this point we know we're appending.
    if (_M_mode & ios_base::in) {
      ptrdiff_t __get_offset = this->gptr() - this->eback();
      _M_str.append(__s, __s + __STATIC_CAST(ptrdiff_t, __n));

      _CharT* __data_ptr = __CONST_CAST(_CharT*, _M_str.data());
      size_t __data_size = _M_str.size();

      this->setg(__data_ptr, __data_ptr + __get_offset, __data_ptr + __data_size);
      this->setp(__data_ptr, __data_ptr + __data_size);
      this->pbump((int)__data_size);
    }
    else {
      _M_append_buffer();
      _M_str.append(__s, __s + __STATIC_CAST(ptrdiff_t, __n));
    }

    __nwritten += __n;
  }

  return __nwritten;
}

template <class _CharT, class _Traits, class _Alloc>
streamsize
basic_stringbuf<_CharT, _Traits, _Alloc>::_M_xsputnc(char_type __c,
                                                     streamsize __n) {
  streamsize __nwritten = 0;

  if ((_M_mode & ios_base::out) && __n > 0) {
    // If the put pointer is somewhere in the middle of the string,
    // then overwrite instead of append.
    if (this->pbase() == _M_str.data()) {
      ptrdiff_t __avail = _M_str.data() + _M_str.size() - this->pptr();
      if (__avail > __n) {
        _Traits::assign(this->pptr(), __STATIC_CAST(size_t, __n), __c);
        this->pbump(__STATIC_CAST(int, __n));
        return __n;
      }
      else {
        _Traits::assign(this->pptr(), __avail, __c);
        __nwritten += __avail;
        __n -= __avail;
        this->setp(_M_Buf, _M_Buf + __STATIC_CAST(int,_S_BufSiz));
      }
    }

    // At this point we know we're appending.
    size_t __app_size = sizeof(streamsize) > sizeof(size_t) ? __STATIC_CAST(size_t, (min)(__n, __STATIC_CAST(streamsize, _M_str.max_size())))
                                                            : __STATIC_CAST(size_t, __n);
    if (this->_M_mode & ios_base::in) {
      ptrdiff_t __get_offset = this->gptr() - this->eback();
      _M_str.append(__app_size, __c);

      _CharT* __data_ptr = __CONST_CAST(_CharT*,_M_str.data());
      size_t __data_size = _M_str.size();