streambuf_iterator.h
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// Streambuf iterators
// Copyright (C) 1997-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file bits/streambuf_iterator.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{iterator}
*/
#ifndef _STREAMBUF_ITERATOR_H
#define _STREAMBUF_ITERATOR_H 1
#pragma GCC system_header
#include <streambuf>
#include <debug/debug.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @addtogroup iterators
* @{
*/
// 24.5.3 Template class istreambuf_iterator
/// Provides input iterator semantics for streambufs.
template<typename _CharT, typename _Traits>
class istreambuf_iterator
: public iterator<input_iterator_tag, _CharT, typename _Traits::off_type,
_CharT*,
#if __cplusplus >= 201103L
// LWG 445.
_CharT>
#else
_CharT&>
#endif
{
public:
// Types:
//@{
/// Public typedefs
typedef _CharT char_type;
typedef _Traits traits_type;
typedef typename _Traits::int_type int_type;
typedef basic_streambuf<_CharT, _Traits> streambuf_type;
typedef basic_istream<_CharT, _Traits> istream_type;
//@}
template<typename _CharT2>
friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
ostreambuf_iterator<_CharT2> >::__type
copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>,
ostreambuf_iterator<_CharT2>);
template<bool _IsMove, typename _CharT2>
friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
_CharT2*>::__type
__copy_move_a2(istreambuf_iterator<_CharT2>,
istreambuf_iterator<_CharT2>, _CharT2*);
template<typename _CharT2>
friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
istreambuf_iterator<_CharT2> >::__type
find(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>,
const _CharT2&);
private:
// 24.5.3 istreambuf_iterator
// p 1
// If the end of stream is reached (streambuf_type::sgetc()
// returns traits_type::eof()), the iterator becomes equal to
// the "end of stream" iterator value.
// NB: This implementation assumes the "end of stream" value
// is EOF, or -1.
mutable streambuf_type* _M_sbuf;
mutable int_type _M_c;
public:
/// Construct end of input stream iterator.
_GLIBCXX_CONSTEXPR istreambuf_iterator() _GLIBCXX_USE_NOEXCEPT
: _M_sbuf(0), _M_c(traits_type::eof()) { }
#if __cplusplus >= 201103L
istreambuf_iterator(const istreambuf_iterator&) noexcept = default;
~istreambuf_iterator() = default;
#endif
/// Construct start of input stream iterator.
istreambuf_iterator(istream_type& __s) _GLIBCXX_USE_NOEXCEPT
: _M_sbuf(__s.rdbuf()), _M_c(traits_type::eof()) { }
/// Construct start of streambuf iterator.
istreambuf_iterator(streambuf_type* __s) _GLIBCXX_USE_NOEXCEPT
: _M_sbuf(__s), _M_c(traits_type::eof()) { }
/// Return the current character pointed to by iterator. This returns
/// streambuf.sgetc(). It cannot be assigned. NB: The result of
/// operator*() on an end of stream is undefined.
char_type
operator*() const
{
#ifdef _GLIBCXX_DEBUG_PEDANTIC
// Dereferencing a past-the-end istreambuf_iterator is a
// libstdc++ extension
__glibcxx_requires_cond(!_M_at_eof(),
_M_message(__gnu_debug::__msg_deref_istreambuf)
._M_iterator(*this));
#endif
return traits_type::to_char_type(_M_get());
}
/// Advance the iterator. Calls streambuf.sbumpc().
istreambuf_iterator&
operator++()
{
__glibcxx_requires_cond(!_M_at_eof(),
_M_message(__gnu_debug::__msg_inc_istreambuf)
._M_iterator(*this));
if (_M_sbuf)
{
_M_sbuf->sbumpc();
_M_c = traits_type::eof();
}
return *this;
}
/// Advance the iterator. Calls streambuf.sbumpc().
istreambuf_iterator
operator++(int)
{
__glibcxx_requires_cond(!_M_at_eof(),
_M_message(__gnu_debug::__msg_inc_istreambuf)
._M_iterator(*this));
istreambuf_iterator __old = *this;
if (_M_sbuf)
{
__old._M_c = _M_sbuf->sbumpc();
_M_c = traits_type::eof();
}
return __old;
}
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 110 istreambuf_iterator::equal not const
// NB: there is also number 111 (NAD, Future) pending on this function.
/// Return true both iterators are end or both are not end.
bool
equal(const istreambuf_iterator& __b) const
{ return _M_at_eof() == __b._M_at_eof(); }
private:
int_type
_M_get() const
{
const int_type __eof = traits_type::eof();
int_type __ret = __eof;
if (_M_sbuf)
{
if (!traits_type::eq_int_type(_M_c, __eof))
__ret = _M_c;
else if (!traits_type::eq_int_type((__ret = _M_sbuf->sgetc()),
__eof))
_M_c = __ret;
else
_M_sbuf = 0;
}
return __ret;
}
bool
_M_at_eof() const
{
const int_type __eof = traits_type::eof();
return traits_type::eq_int_type(_M_get(), __eof);
}
};
template<typename _CharT, typename _Traits>
inline bool
operator==(const istreambuf_iterator<_CharT, _Traits>& __a,
const istreambuf_iterator<_CharT, _Traits>& __b)
{ return __a.equal(__b); }
template<typename _CharT, typename _Traits>
inline bool
operator!=(const istreambuf_iterator<_CharT, _Traits>& __a,
const istreambuf_iterator<_CharT, _Traits>& __b)
{ return !__a.equal(__b); }
/// Provides output iterator semantics for streambufs.
template<typename _CharT, typename _Traits>
class ostreambuf_iterator
: public iterator<output_iterator_tag, void, void, void, void>
{
public:
// Types:
//@{
/// Public typedefs
typedef _CharT char_type;
typedef _Traits traits_type;
typedef basic_streambuf<_CharT, _Traits> streambuf_type;
typedef basic_ostream<_CharT, _Traits> ostream_type;
//@}
template<typename _CharT2>
friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
ostreambuf_iterator<_CharT2> >::__type
copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>,
ostreambuf_iterator<_CharT2>);
private:
streambuf_type* _M_sbuf;
bool _M_failed;
public:
/// Construct output iterator from ostream.
ostreambuf_iterator(ostream_type& __s) _GLIBCXX_USE_NOEXCEPT
: _M_sbuf(__s.rdbuf()), _M_failed(!_M_sbuf) { }
/// Construct output iterator from streambuf.
ostreambuf_iterator(streambuf_type* __s) _GLIBCXX_USE_NOEXCEPT
: _M_sbuf(__s), _M_failed(!_M_sbuf) { }
/// Write character to streambuf. Calls streambuf.sputc().
ostreambuf_iterator&
operator=(_CharT __c)
{
if (!_M_failed &&
_Traits::eq_int_type(_M_sbuf->sputc(__c), _Traits::eof()))
_M_failed = true;
return *this;
}
/// Return *this.
ostreambuf_iterator&
operator*()
{ return *this; }
/// Return *this.
ostreambuf_iterator&
operator++(int)
{ return *this; }
/// Return *this.
ostreambuf_iterator&
operator++()
{ return *this; }
/// Return true if previous operator=() failed.
bool
failed() const _GLIBCXX_USE_NOEXCEPT
{ return _M_failed; }
ostreambuf_iterator&
_M_put(const _CharT* __ws, streamsize __len)
{
if (__builtin_expect(!_M_failed, true)
&& __builtin_expect(this->_M_sbuf->sputn(__ws, __len) != __len,
false))
_M_failed = true;
return *this;
}
};
// Overloads for streambuf iterators.
template<typename _CharT>
typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
ostreambuf_iterator<_CharT> >::__type
copy(istreambuf_iterator<_CharT> __first,
istreambuf_iterator<_CharT> __last,
ostreambuf_iterator<_CharT> __result)
{
if (__first._M_sbuf && !__last._M_sbuf && !__result._M_failed)
{
bool __ineof;
__copy_streambufs_eof(__first._M_sbuf, __result._M_sbuf, __ineof);
if (!__ineof)
__result._M_failed = true;
}
return __result;
}
template<bool _IsMove, typename _CharT>
typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
ostreambuf_iterator<_CharT> >::__type
__copy_move_a2(_CharT* __first, _CharT* __last,
ostreambuf_iterator<_CharT> __result)
{
const streamsize __num = __last - __first;
if (__num > 0)
__result._M_put(__first, __num);
return __result;
}
template<bool _IsMove, typename _CharT>
typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
ostreambuf_iterator<_CharT> >::__type
__copy_move_a2(const _CharT* __first, const _CharT* __last,
ostreambuf_iterator<_CharT> __result)
{
const streamsize __num = __last - __first;
if (__num > 0)
__result._M_put(__first, __num);
return __result;
}
template<bool _IsMove, typename _CharT>
typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
_CharT*>::__type
__copy_move_a2(istreambuf_iterator<_CharT> __first,
istreambuf_iterator<_CharT> __last, _CharT* __result)
{
typedef istreambuf_iterator<_CharT> __is_iterator_type;
typedef typename __is_iterator_type::traits_type traits_type;
typedef typename __is_iterator_type::streambuf_type streambuf_type;
typedef typename traits_type::int_type int_type;
if (__first._M_sbuf && !__last._M_sbuf)
{
streambuf_type* __sb = __first._M_sbuf;
int_type __c = __sb->sgetc();
while (!traits_type::eq_int_type(__c, traits_type::eof()))
{
const streamsize __n = __sb->egptr() - __sb->gptr();
if (__n > 1)
{
traits_type::copy(__result, __sb->gptr(), __n);
__sb->__safe_gbump(__n);
__result += __n;
__c = __sb->underflow();
}
else
{
*__result++ = traits_type::to_char_type(__c);
__c = __sb->snextc();
}
}
}
return __result;
}
template<typename _CharT>
typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
istreambuf_iterator<_CharT> >::__type
find(istreambuf_iterator<_CharT> __first,
istreambuf_iterator<_CharT> __last, const _CharT& __val)
{
typedef istreambuf_iterator<_CharT> __is_iterator_type;
typedef typename __is_iterator_type::traits_type traits_type;
typedef typename __is_iterator_type::streambuf_type streambuf_type;
typedef typename traits_type::int_type int_type;
if (__first._M_sbuf && !__last._M_sbuf)
{
const int_type __ival = traits_type::to_int_type(__val);
streambuf_type* __sb = __first._M_sbuf;
int_type __c = __sb->sgetc();
while (!traits_type::eq_int_type(__c, traits_type::eof())
&& !traits_type::eq_int_type(__c, __ival))
{
streamsize __n = __sb->egptr() - __sb->gptr();
if (__n > 1)
{
const _CharT* __p = traits_type::find(__sb->gptr(),
__n, __val);
if (__p)
__n = __p - __sb->gptr();
__sb->__safe_gbump(__n);
__c = __sb->sgetc();
}
else
__c = __sb->snextc();
}
if (!traits_type::eq_int_type(__c, traits_type::eof()))
__first._M_c = __c;
else
__first._M_sbuf = 0;
}
return __first;
}
// @} group iterators
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif