# basic_string.tcc

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    00001 // Components for manipulating sequences of characters -*- C++ -*-
    00002
    00003 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
    00004 // 2006, 2007
    00005 // Free Software Foundation, Inc.
    00006 //
    00007 // This file is part of the GNU ISO C++ Library.  This library is free
    00008 // software; you can redistribute it and/or modify it under the
    00009 // terms of the GNU General Public License as published by the
    00010 // Free Software Foundation; either version 2, or (at your option)
    00011 // any later version.
    00012
    00013 // This library is distributed in the hope that it will be useful,
    00014 // but WITHOUT ANY WARRANTY; without even the implied warranty of
    00015 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00016 // GNU General Public License for more details.
    00017
    00018 // You should have received a copy of the GNU General Public License along
    00019 // with this library; see the file COPYING.  If not, write to the Free
    00020 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
    00021 // USA.
    00022
    00023 // As a special exception, you may use this file as part of a free software
    00024 // library without restriction.  Specifically, if other files instantiate
    00025 // templates or use macros or inline functions from this file, or you compile
    00026 // this file and link it with other files to produce an executable, this
    00027 // file does not by itself cause the resulting executable to be covered by
    00028 // the GNU General Public License.  This exception does not however
    00029 // invalidate any other reasons why the executable file might be covered by
    00030 // the GNU General Public License.
    00031
    00032 /** @file basic_string.tcc
    00033  *  This is an internal header file, included by other library headers.
    00034  *  You should not attempt to use it directly.
    00035  */
    00036
    00037 //
    00038 // ISO C++ 14882: 21  Strings library
    00039 //
    00040
    00041 // Written by Jason Merrill based upon the specification by Takanori Adachi
    00042 // in ANSI X3J16/94-0013R2.  Rewritten by Nathan Myers to ISO-14882.
    00043
    00044 #ifndef _BASIC_STRING_TCC
    00045 #define _BASIC_STRING_TCC 1
    00046
    00047 #pragma GCC system_header
    00048
    00049 #include <cxxabi-forced.h>
    00050
    00051 _GLIBCXX_BEGIN_NAMESPACE(std)
    00052
    00053   template<typename _CharT, typename _Traits, typename _Alloc>
    00054     const typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00055     basic_string<_CharT, _Traits, _Alloc>::
    00056     _Rep::_S_max_size = (((npos - sizeof(_Rep_base))/sizeof(_CharT)) - 1) / 4;
    00057
    00058   template<typename _CharT, typename _Traits, typename _Alloc>
    00059     const _CharT
    00060     basic_string<_CharT, _Traits, _Alloc>::
    00061     _Rep::_S_terminal = _CharT();
    00062
    00063   template<typename _CharT, typename _Traits, typename _Alloc>
    00064     const typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00065     basic_string<_CharT, _Traits, _Alloc>::npos;
    00066
    00067   // Linker sets _S_empty_rep_storage to all 0s (one reference, empty string)
    00068   // at static init time (before static ctors are run).
    00069   template<typename _CharT, typename _Traits, typename _Alloc>
    00070     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00071     basic_string<_CharT, _Traits, _Alloc>::_Rep::_S_empty_rep_storage[
    00072     (sizeof(_Rep_base) + sizeof(_CharT) + sizeof(size_type) - 1) /
    00073       sizeof(size_type)];
    00074
    00075   // NB: This is the special case for Input Iterators, used in
    00076   // istreambuf_iterators, etc.
    00077   // Input Iterators have a cost structure very different from
    00078   // pointers, calling for a different coding style.
    00079   template<typename _CharT, typename _Traits, typename _Alloc>
    00080     template<typename _InIterator>
    00081       _CharT*
    00082       basic_string<_CharT, _Traits, _Alloc>::
    00083       _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
    00084            input_iterator_tag)
    00085       {
    00086 #ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
    00087     if (__beg == __end && __a == _Alloc())
    00088       return _S_empty_rep()._M_refdata();
    00089 #endif
    00090     // Avoid reallocation for common case.
    00091     _CharT __buf[128];
    00092     size_type __len = 0;
    00093     while (__beg != __end && __len < sizeof(__buf) / sizeof(_CharT))
    00094       {
    00095         __buf[__len++] = *__beg;
    00096         ++__beg;
    00097       }
    00098     _Rep* __r = _Rep::_S_create(__len, size_type(0), __a);
    00099     _M_copy(__r->_M_refdata(), __buf, __len);
    00100     try
    00101       {
    00102         while (__beg != __end)
    00103           {
    00104         if (__len == __r->_M_capacity)
    00105           {
    00106             // Allocate more space.
    00107             _Rep* __another = _Rep::_S_create(__len + 1, __len, __a);
    00108             _M_copy(__another->_M_refdata(), __r->_M_refdata(), __len);
    00109             __r->_M_destroy(__a);
    00110             __r = __another;
    00111           }
    00112         __r->_M_refdata()[__len++] = *__beg;
    00113         ++__beg;
    00114           }
    00115       }
    00116     catch(...)
    00117       {
    00118         __r->_M_destroy(__a);
    00119         __throw_exception_again;
    00120       }
    00121     __r->_M_set_length_and_sharable(__len);
    00122     return __r->_M_refdata();
    00123       }
    00124
    00125   template<typename _CharT, typename _Traits, typename _Alloc>
    00126     template <typename _InIterator>
    00127       _CharT*
    00128       basic_string<_CharT, _Traits, _Alloc>::
    00129       _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
    00130            forward_iterator_tag)
    00131       {
    00132 #ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
    00133     if (__beg == __end && __a == _Alloc())
    00134       return _S_empty_rep()._M_refdata();
    00135 #endif
    00136     // NB: Not required, but considered best practice.
    00137     if (__builtin_expect(__gnu_cxx::__is_null_pointer(__beg)
    00138                  && __beg != __end, 0))
    00139       __throw_logic_error(__N("basic_string::_S_construct NULL not valid"));
    00140
    00141     const size_type __dnew = static_cast<size_type>(std::distance(__beg,
    00142                                       __end));
    00143     // Check for out_of_range and length_error exceptions.
    00144     _Rep* __r = _Rep::_S_create(__dnew, size_type(0), __a);
    00145     try
    00146       { _S_copy_chars(__r->_M_refdata(), __beg, __end); }
    00147     catch(...)
    00148       {
    00149         __r->_M_destroy(__a);
    00150         __throw_exception_again;
    00151       }
    00152     __r->_M_set_length_and_sharable(__dnew);
    00153     return __r->_M_refdata();
    00154       }
    00155
    00156   template<typename _CharT, typename _Traits, typename _Alloc>
    00157     _CharT*
    00158     basic_string<_CharT, _Traits, _Alloc>::
    00159     _S_construct(size_type __n, _CharT __c, const _Alloc& __a)
    00160     {
    00161 #ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
    00162       if (__n == 0 && __a == _Alloc())
    00163     return _S_empty_rep()._M_refdata();
    00164 #endif
    00165       // Check for out_of_range and length_error exceptions.
    00166       _Rep* __r = _Rep::_S_create(__n, size_type(0), __a);
    00167       if (__n)
    00168     _M_assign(__r->_M_refdata(), __n, __c);
    00169
    00170       __r->_M_set_length_and_sharable(__n);
    00171       return __r->_M_refdata();
    00172     }
    00173
    00174   template<typename _CharT, typename _Traits, typename _Alloc>
    00175     basic_string<_CharT, _Traits, _Alloc>::
    00176     basic_string(const basic_string& __str)
    00177     : _M_dataplus(__str._M_rep()->_M_grab(_Alloc(__str.get_allocator()),
    00178                       __str.get_allocator()),
    00179           __str.get_allocator())
    00180     { }
    00181
    00182   template<typename _CharT, typename _Traits, typename _Alloc>
    00183     basic_string<_CharT, _Traits, _Alloc>::
    00184     basic_string(const _Alloc& __a)
    00185     : _M_dataplus(_S_construct(size_type(), _CharT(), __a), __a)
    00186     { }
    00187
    00188   template<typename _CharT, typename _Traits, typename _Alloc>
    00189     basic_string<_CharT, _Traits, _Alloc>::
    00190     basic_string(const basic_string& __str, size_type __pos, size_type __n)
    00191     : _M_dataplus(_S_construct(__str._M_data()
    00192                    + __str._M_check(__pos,
    00193                         "basic_string::basic_string"),
    00194                    __str._M_data() + __str._M_limit(__pos, __n)
    00195                    + __pos, _Alloc()), _Alloc())
    00196     { }
    00197
    00198   template<typename _CharT, typename _Traits, typename _Alloc>
    00199     basic_string<_CharT, _Traits, _Alloc>::
    00200     basic_string(const basic_string& __str, size_type __pos,
    00201          size_type __n, const _Alloc& __a)
    00202     : _M_dataplus(_S_construct(__str._M_data()
    00203                    + __str._M_check(__pos,
    00204                         "basic_string::basic_string"),
    00205                    __str._M_data() + __str._M_limit(__pos, __n)
    00206                    + __pos, __a), __a)
    00207     { }
    00208
    00209   // TBD: DPG annotate
    00210   template<typename _CharT, typename _Traits, typename _Alloc>
    00211     basic_string<_CharT, _Traits, _Alloc>::
    00212     basic_string(const _CharT* __s, size_type __n, const _Alloc& __a)
    00213     : _M_dataplus(_S_construct(__s, __s + __n, __a), __a)
    00214     { }
    00215
    00216   // TBD: DPG annotate
    00217   template<typename _CharT, typename _Traits, typename _Alloc>
    00218     basic_string<_CharT, _Traits, _Alloc>::
    00219     basic_string(const _CharT* __s, const _Alloc& __a)
    00220     : _M_dataplus(_S_construct(__s, __s ? __s + traits_type::length(__s) :
    00221                    __s + npos, __a), __a)
    00222     { }
    00223
    00224   template<typename _CharT, typename _Traits, typename _Alloc>
    00225     basic_string<_CharT, _Traits, _Alloc>::
    00226     basic_string(size_type __n, _CharT __c, const _Alloc& __a)
    00227     : _M_dataplus(_S_construct(__n, __c, __a), __a)
    00228     { }
    00229
    00230   // TBD: DPG annotate
    00231   template<typename _CharT, typename _Traits, typename _Alloc>
    00232     template<typename _InputIterator>
    00233     basic_string<_CharT, _Traits, _Alloc>::
    00234     basic_string(_InputIterator __beg, _InputIterator __end, const _Alloc& __a)
    00235     : _M_dataplus(_S_construct(__beg, __end, __a), __a)
    00236     { }
    00237
    00238   template<typename _CharT, typename _Traits, typename _Alloc>
    00239     basic_string<_CharT, _Traits, _Alloc>&
    00240     basic_string<_CharT, _Traits, _Alloc>::
    00241     assign(const basic_string& __str)
    00242     {
    00243       if (_M_rep() != __str._M_rep())
    00244     {
    00245       // XXX MT
    00246       const allocator_type __a = this->get_allocator();
    00247       _CharT* __tmp = __str._M_rep()->_M_grab(__a, __str.get_allocator());
    00248       _M_rep()->_M_dispose(__a);
    00249       _M_data(__tmp);
    00250     }
    00251       return *this;
    00252     }
    00253
    00254   template<typename _CharT, typename _Traits, typename _Alloc>
    00255     basic_string<_CharT, _Traits, _Alloc>&
    00256     basic_string<_CharT, _Traits, _Alloc>::
    00257     assign(const _CharT* __s, size_type __n)
    00258     {
    00259       __glibcxx_requires_string_len(__s, __n);
    00260       _M_check_length(this->size(), __n, "basic_string::assign");
    00261       if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
    00262     return _M_replace_safe(size_type(0), this->size(), __s, __n);
    00263       else
    00264     {
    00265       // Work in-place.
    00266       const size_type __pos = __s - _M_data();
    00267       if (__pos >= __n)
    00268         _M_copy(_M_data(), __s, __n);
    00269       else if (__pos)
    00270         _M_move(_M_data(), __s, __n);
    00271       _M_rep()->_M_set_length_and_sharable(__n);
    00272       return *this;
    00273     }
    00274      }
    00275
    00276   template<typename _CharT, typename _Traits, typename _Alloc>
    00277     basic_string<_CharT, _Traits, _Alloc>&
    00278     basic_string<_CharT, _Traits, _Alloc>::
    00279     append(size_type __n, _CharT __c)
    00280     {
    00281       if (__n)
    00282     {
    00283       _M_check_length(size_type(0), __n, "basic_string::append");
    00284       const size_type __len = __n + this->size();
    00285       if (__len > this->capacity() || _M_rep()->_M_is_shared())
    00286         this->reserve(__len);
    00287       _M_assign(_M_data() + this->size(), __n, __c);
    00288       _M_rep()->_M_set_length_and_sharable(__len);
    00289     }
    00290       return *this;
    00291     }
    00292
    00293   template<typename _CharT, typename _Traits, typename _Alloc>
    00294     basic_string<_CharT, _Traits, _Alloc>&
    00295     basic_string<_CharT, _Traits, _Alloc>::
    00296     append(const _CharT* __s, size_type __n)
    00297     {
    00298       __glibcxx_requires_string_len(__s, __n);
    00299       if (__n)
    00300     {
    00301       _M_check_length(size_type(0), __n, "basic_string::append");
    00302       const size_type __len = __n + this->size();
    00303       if (__len > this->capacity() || _M_rep()->_M_is_shared())
    00304         {
    00305           if (_M_disjunct(__s))
    00306         this->reserve(__len);
    00307           else
    00308         {
    00309           const size_type __off = __s - _M_data();
    00310           this->reserve(__len);
    00311           __s = _M_data() + __off;
    00312         }
    00313         }
    00314       _M_copy(_M_data() + this->size(), __s, __n);
    00315       _M_rep()->_M_set_length_and_sharable(__len);
    00316     }
    00317       return *this;
    00318     }
    00319
    00320   template<typename _CharT, typename _Traits, typename _Alloc>
    00321     basic_string<_CharT, _Traits, _Alloc>&
    00322     basic_string<_CharT, _Traits, _Alloc>::
    00323     append(const basic_string& __str)
    00324     {
    00325       const size_type __size = __str.size();
    00326       if (__size)
    00327     {
    00328       const size_type __len = __size + this->size();
    00329       if (__len > this->capacity() || _M_rep()->_M_is_shared())
    00330         this->reserve(__len);
    00331       _M_copy(_M_data() + this->size(), __str._M_data(), __size);
    00332       _M_rep()->_M_set_length_and_sharable(__len);
    00333     }
    00334       return *this;
    00335     }
    00336
    00337   template<typename _CharT, typename _Traits, typename _Alloc>
    00338     basic_string<_CharT, _Traits, _Alloc>&
    00339     basic_string<_CharT, _Traits, _Alloc>::
    00340     append(const basic_string& __str, size_type __pos, size_type __n)
    00341     {
    00342       __str._M_check(__pos, "basic_string::append");
    00343       __n = __str._M_limit(__pos, __n);
    00344       if (__n)
    00345     {
    00346       const size_type __len = __n + this->size();
    00347       if (__len > this->capacity() || _M_rep()->_M_is_shared())
    00348         this->reserve(__len);
    00349       _M_copy(_M_data() + this->size(), __str._M_data() + __pos, __n);
    00350       _M_rep()->_M_set_length_and_sharable(__len);
    00351     }
    00352       return *this;
    00353     }
    00354
    00355    template<typename _CharT, typename _Traits, typename _Alloc>
    00356      basic_string<_CharT, _Traits, _Alloc>&
    00357      basic_string<_CharT, _Traits, _Alloc>::
    00358      insert(size_type __pos, const _CharT* __s, size_type __n)
    00359      {
    00360        __glibcxx_requires_string_len(__s, __n);
    00361        _M_check(__pos, "basic_string::insert");
    00362        _M_check_length(size_type(0), __n, "basic_string::insert");
    00363        if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
    00364          return _M_replace_safe(__pos, size_type(0), __s, __n);
    00365        else
    00366          {
    00367            // Work in-place.
    00368            const size_type __off = __s - _M_data();
    00369            _M_mutate(__pos, 0, __n);
    00370            __s = _M_data() + __off;
    00371            _CharT* __p = _M_data() + __pos;
    00372            if (__s  + __n <= __p)
    00373              _M_copy(__p, __s, __n);
    00374            else if (__s >= __p)
    00375              _M_copy(__p, __s + __n, __n);
    00376            else
    00377              {
    00378            const size_type __nleft = __p - __s;
    00379                _M_copy(__p, __s, __nleft);
    00380                _M_copy(__p + __nleft, __p + __n, __n - __nleft);
    00381              }
    00382            return *this;
    00383          }
    00384      }
    00385
    00386    template<typename _CharT, typename _Traits, typename _Alloc>
    00387      basic_string<_CharT, _Traits, _Alloc>&
    00388      basic_string<_CharT, _Traits, _Alloc>::
    00389      replace(size_type __pos, size_type __n1, const _CharT* __s,
    00390          size_type __n2)
    00391      {
    00392        __glibcxx_requires_string_len(__s, __n2);
    00393        _M_check(__pos, "basic_string::replace");
    00394        __n1 = _M_limit(__pos, __n1);
    00395        _M_check_length(__n1, __n2, "basic_string::replace");
    00396        bool __left;
    00397        if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
    00398          return _M_replace_safe(__pos, __n1, __s, __n2);
    00399        else if ((__left = __s + __n2 <= _M_data() + __pos)
    00400         || _M_data() + __pos + __n1 <= __s)
    00401      {
    00402        // Work in-place: non-overlapping case.
    00403        size_type __off = __s - _M_data();
    00404        __left ? __off : (__off += __n2 - __n1);
    00405        _M_mutate(__pos, __n1, __n2);
    00406        _M_copy(_M_data() + __pos, _M_data() + __off, __n2);
    00407        return *this;
    00408      }
    00409        else
    00410      {
    00411        // Todo: overlapping case.
    00412        const basic_string __tmp(__s, __n2);
    00413        return _M_replace_safe(__pos, __n1, __tmp._M_data(), __n2);
    00414      }
    00415      }
    00416
    00417   template<typename _CharT, typename _Traits, typename _Alloc>
    00418     void
    00419     basic_string<_CharT, _Traits, _Alloc>::_Rep::
    00420     _M_destroy(const _Alloc& __a) throw ()
    00421     {
    00422       const size_type __size = sizeof(_Rep_base) +
    00423                            (this->_M_capacity + 1) * sizeof(_CharT);
    00424       _Raw_bytes_alloc(__a).deallocate(reinterpret_cast<char*>(this), __size);
    00425     }
    00426
    00427   template<typename _CharT, typename _Traits, typename _Alloc>
    00428     void
    00429     basic_string<_CharT, _Traits, _Alloc>::
    00430     _M_leak_hard()
    00431     {
    00432 #ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
    00433       if (_M_rep() == &_S_empty_rep())
    00434     return;
    00435 #endif
    00436       if (_M_rep()->_M_is_shared())
    00437     _M_mutate(0, 0, 0);
    00438       _M_rep()->_M_set_leaked();
    00439     }
    00440
    00441   template<typename _CharT, typename _Traits, typename _Alloc>
    00442     void
    00443     basic_string<_CharT, _Traits, _Alloc>::
    00444     _M_mutate(size_type __pos, size_type __len1, size_type __len2)
    00445     {
    00446       const size_type __old_size = this->size();
    00447       const size_type __new_size = __old_size + __len2 - __len1;
    00448       const size_type __how_much = __old_size - __pos - __len1;
    00449
    00450       if (__new_size > this->capacity() || _M_rep()->_M_is_shared())
    00451     {
    00452       // Must reallocate.
    00453       const allocator_type __a = get_allocator();
    00454       _Rep* __r = _Rep::_S_create(__new_size, this->capacity(), __a);
    00455
    00456       if (__pos)
    00457         _M_copy(__r->_M_refdata(), _M_data(), __pos);
    00458       if (__how_much)
    00459         _M_copy(__r->_M_refdata() + __pos + __len2,
    00460             _M_data() + __pos + __len1, __how_much);
    00461
    00462       _M_rep()->_M_dispose(__a);
    00463       _M_data(__r->_M_refdata());
    00464     }
    00465       else if (__how_much && __len1 != __len2)
    00466     {
    00467       // Work in-place.
    00468       _M_move(_M_data() + __pos + __len2,
    00469           _M_data() + __pos + __len1, __how_much);
    00470     }
    00471       _M_rep()->_M_set_length_and_sharable(__new_size);
    00472     }
    00473
    00474   template<typename _CharT, typename _Traits, typename _Alloc>
    00475     void
    00476     basic_string<_CharT, _Traits, _Alloc>::
    00477     reserve(size_type __res)
    00478     {
    00479       if (__res != this->capacity() || _M_rep()->_M_is_shared())
    00480         {
    00481       // Make sure we don't shrink below the current size
    00482       if (__res < this->size())
    00483         __res = this->size();
    00484       const allocator_type __a = get_allocator();
    00485       _CharT* __tmp = _M_rep()->_M_clone(__a, __res - this->size());
    00486       _M_rep()->_M_dispose(__a);
    00487       _M_data(__tmp);
    00488         }
    00489     }
    00490
    00491   template<typename _CharT, typename _Traits, typename _Alloc>
    00492     void
    00493     basic_string<_CharT, _Traits, _Alloc>::
    00494     swap(basic_string& __s)
    00495     {
    00496       if (_M_rep()->_M_is_leaked())
    00497     _M_rep()->_M_set_sharable();
    00498       if (__s._M_rep()->_M_is_leaked())
    00499     __s._M_rep()->_M_set_sharable();
    00500       if (this->get_allocator() == __s.get_allocator())
    00501     {
    00502       _CharT* __tmp = _M_data();
    00503       _M_data(__s._M_data());
    00504       __s._M_data(__tmp);
    00505     }
    00506       // The code below can usually be optimized away.
    00507       else
    00508     {
    00509       const basic_string __tmp1(_M_ibegin(), _M_iend(),
    00510                     __s.get_allocator());
    00511       const basic_string __tmp2(__s._M_ibegin(), __s._M_iend(),
    00512                     this->get_allocator());
    00513       *this = __tmp2;
    00514       __s = __tmp1;
    00515     }
    00516     }
    00517
    00518   template<typename _CharT, typename _Traits, typename _Alloc>
    00519     typename basic_string<_CharT, _Traits, _Alloc>::_Rep*
    00520     basic_string<_CharT, _Traits, _Alloc>::_Rep::
    00521     _S_create(size_type __capacity, size_type __old_capacity,
    00522           const _Alloc& __alloc)
    00523     {
    00524       // _GLIBCXX_RESOLVE_LIB_DEFECTS
    00525       // 83.  String::npos vs. string::max_size()
    00526       if (__capacity > _S_max_size)
    00527     __throw_length_error(__N("basic_string::_S_create"));
    00528
    00529       // The standard places no restriction on allocating more memory
    00530       // than is strictly needed within this layer at the moment or as
    00531       // requested by an explicit application call to reserve().
    00532
    00533       // Many malloc implementations perform quite poorly when an
    00534       // application attempts to allocate memory in a stepwise fashion
    00535       // growing each allocation size by only 1 char.  Additionally,
    00536       // it makes little sense to allocate less linear memory than the
    00537       // natural blocking size of the malloc implementation.
    00538       // Unfortunately, we would need a somewhat low-level calculation
    00539       // with tuned parameters to get this perfect for any particular
    00540       // malloc implementation.  Fortunately, generalizations about
    00541       // common features seen among implementations seems to suffice.
    00542
    00543       // __pagesize need not match the actual VM page size for good
    00544       // results in practice, thus we pick a common value on the low
    00545       // side.  __malloc_header_size is an estimate of the amount of
    00546       // overhead per memory allocation (in practice seen N * sizeof
    00547       // (void*) where N is 0, 2 or 4).  According to folklore,
    00548       // picking this value on the high side is better than
    00549       // low-balling it (especially when this algorithm is used with
    00550       // malloc implementations that allocate memory blocks rounded up
    00551       // to a size which is a power of 2).
    00552       const size_type __pagesize = 4096;
    00553       const size_type __malloc_header_size = 4 * sizeof(void*);
    00554
    00555       // The below implements an exponential growth policy, necessary to
    00556       // meet amortized linear time requirements of the library: see
    00557       // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
    00558       // It's active for allocations requiring an amount of memory above
    00559       // system pagesize. This is consistent with the requirements of the
    00560       // standard: http://gcc.gnu.org/ml/libstdc++/2001-07/msg00130.html
    00561       if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
    00562     __capacity = 2 * __old_capacity;
    00563
    00564       // NB: Need an array of char_type[__capacity], plus a terminating
    00565       // null char_type() element, plus enough for the _Rep data structure.
    00566       // Whew. Seemingly so needy, yet so elemental.
    00567       size_type __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
    00568
    00569       const size_type __adj_size = __size + __malloc_header_size;
    00570       if (__adj_size > __pagesize && __capacity > __old_capacity)
    00571     {
    00572       const size_type __extra = __pagesize - __adj_size % __pagesize;
    00573       __capacity += __extra / sizeof(_CharT);
    00574       // Never allocate a string bigger than _S_max_size.
    00575       if (__capacity > _S_max_size)
    00576         __capacity = _S_max_size;
    00577       __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
    00578     }
    00579
    00580       // NB: Might throw, but no worries about a leak, mate: _Rep()
    00581       // does not throw.
    00582       void* __place = _Raw_bytes_alloc(__alloc).allocate(__size);
    00583       _Rep *__p = new (__place) _Rep;
    00584       __p->_M_capacity = __capacity;
    00585       // ABI compatibility - 3.4.x set in _S_create both
    00586       // _M_refcount and _M_length.  All callers of _S_create
    00587       // in basic_string.tcc then set just _M_length.
    00588       // In 4.0.x and later both _M_refcount and _M_length
    00589       // are initialized in the callers, unfortunately we can
    00590       // have 3.4.x compiled code with _S_create callers inlined
    00591       // calling 4.0.x+ _S_create.
    00592       __p->_M_set_sharable();
    00593       return __p;
    00594     }
    00595
    00596   template<typename _CharT, typename _Traits, typename _Alloc>
    00597     _CharT*
    00598     basic_string<_CharT, _Traits, _Alloc>::_Rep::
    00599     _M_clone(const _Alloc& __alloc, size_type __res)
    00600     {
    00601       // Requested capacity of the clone.
    00602       const size_type __requested_cap = this->_M_length + __res;
    00603       _Rep* __r = _Rep::_S_create(__requested_cap, this->_M_capacity,
    00604                   __alloc);
    00605       if (this->_M_length)
    00606     _M_copy(__r->_M_refdata(), _M_refdata(), this->_M_length);
    00607
    00608       __r->_M_set_length_and_sharable(this->_M_length);
    00609       return __r->_M_refdata();
    00610     }
    00611
    00612   template<typename _CharT, typename _Traits, typename _Alloc>
    00613     void
    00614     basic_string<_CharT, _Traits, _Alloc>::
    00615     resize(size_type __n, _CharT __c)
    00616     {
    00617       const size_type __size = this->size();
    00618       _M_check_length(__size, __n, "basic_string::resize");
    00619       if (__size < __n)
    00620     this->append(__n - __size, __c);
    00621       else if (__n < __size)
    00622     this->erase(__n);
    00623       // else nothing (in particular, avoid calling _M_mutate() unnecessarily.)
    00624     }
    00625
    00626   template<typename _CharT, typename _Traits, typename _Alloc>
    00627     template<typename _InputIterator>
    00628       basic_string<_CharT, _Traits, _Alloc>&
    00629       basic_string<_CharT, _Traits, _Alloc>::
    00630       _M_replace_dispatch(iterator __i1, iterator __i2, _InputIterator __k1,
    00631               _InputIterator __k2, __false_type)
    00632       {
    00633     const basic_string __s(__k1, __k2);
    00634     const size_type __n1 = __i2 - __i1;
    00635     _M_check_length(__n1, __s.size(), "basic_string::_M_replace_dispatch");
    00636     return _M_replace_safe(__i1 - _M_ibegin(), __n1, __s._M_data(),
    00637                    __s.size());
    00638       }
    00639
    00640   template<typename _CharT, typename _Traits, typename _Alloc>
    00641     basic_string<_CharT, _Traits, _Alloc>&
    00642     basic_string<_CharT, _Traits, _Alloc>::
    00643     _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
    00644            _CharT __c)
    00645     {
    00646       _M_check_length(__n1, __n2, "basic_string::_M_replace_aux");
    00647       _M_mutate(__pos1, __n1, __n2);
    00648       if (__n2)
    00649     _M_assign(_M_data() + __pos1, __n2, __c);
    00650       return *this;
    00651     }
    00652
    00653   template<typename _CharT, typename _Traits, typename _Alloc>
    00654     basic_string<_CharT, _Traits, _Alloc>&
    00655     basic_string<_CharT, _Traits, _Alloc>::
    00656     _M_replace_safe(size_type __pos1, size_type __n1, const _CharT* __s,
    00657             size_type __n2)
    00658     {
    00659       _M_mutate(__pos1, __n1, __n2);
    00660       if (__n2)
    00661     _M_copy(_M_data() + __pos1, __s, __n2);
    00662       return *this;
    00663     }
    00664
    00665   template<typename _CharT, typename _Traits, typename _Alloc>
    00666     basic_string<_CharT, _Traits, _Alloc>
    00667     operator+(const _CharT* __lhs,
    00668           const basic_string<_CharT, _Traits, _Alloc>& __rhs)
    00669     {
    00670       __glibcxx_requires_string(__lhs);
    00671       typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
    00672       typedef typename __string_type::size_type   __size_type;
    00673       const __size_type __len = _Traits::length(__lhs);
    00674       __string_type __str;
    00675       __str.reserve(__len + __rhs.size());
    00676       __str.append(__lhs, __len);
    00677       __str.append(__rhs);
    00678       return __str;
    00679     }
    00680
    00681   template<typename _CharT, typename _Traits, typename _Alloc>
    00682     basic_string<_CharT, _Traits, _Alloc>
    00683     operator+(_CharT __lhs, const basic_string<_CharT, _Traits, _Alloc>& __rhs)
    00684     {
    00685       typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
    00686       typedef typename __string_type::size_type   __size_type;
    00687       __string_type __str;
    00688       const __size_type __len = __rhs.size();
    00689       __str.reserve(__len + 1);
    00690       __str.append(__size_type(1), __lhs);
    00691       __str.append(__rhs);
    00692       return __str;
    00693     }
    00694
    00695   template<typename _CharT, typename _Traits, typename _Alloc>
    00696     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00697     basic_string<_CharT, _Traits, _Alloc>::
    00698     copy(_CharT* __s, size_type __n, size_type __pos) const
    00699     {
    00700       _M_check(__pos, "basic_string::copy");
    00701       __n = _M_limit(__pos, __n);
    00702       __glibcxx_requires_string_len(__s, __n);
    00703       if (__n)
    00704     _M_copy(__s, _M_data() + __pos, __n);
    00705       // 21.3.5.7 par 3: do not append null.  (good.)
    00706       return __n;
    00707     }
    00708
    00709   template<typename _CharT, typename _Traits, typename _Alloc>
    00710     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00711     basic_string<_CharT, _Traits, _Alloc>::
    00712     find(const _CharT* __s, size_type __pos, size_type __n) const
    00713     {
    00714       __glibcxx_requires_string_len(__s, __n);
    00715       const size_type __size = this->size();
    00716       const _CharT* __data = _M_data();
    00717
    00718       if (__n == 0)
    00719     return __pos <= __size ? __pos : npos;
    00720
    00721       if (__n <= __size)
    00722     {
    00723       for (; __pos <= __size - __n; ++__pos)
    00724         if (traits_type::eq(__data[__pos], __s[0])
    00725         && traits_type::compare(__data + __pos + 1,
    00726                     __s + 1, __n - 1) == 0)
    00727           return __pos;
    00728     }
    00729       return npos;
    00730     }
    00731
    00732   template<typename _CharT, typename _Traits, typename _Alloc>
    00733     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00734     basic_string<_CharT, _Traits, _Alloc>::
    00735     find(_CharT __c, size_type __pos) const
    00736     {
    00737       size_type __ret = npos;
    00738       const size_type __size = this->size();
    00739       if (__pos < __size)
    00740     {
    00741       const _CharT* __data = _M_data();
    00742       const size_type __n = __size - __pos;
    00743       const _CharT* __p = traits_type::find(__data + __pos, __n, __c);
    00744       if (__p)
    00745         __ret = __p - __data;
    00746     }
    00747       return __ret;
    00748     }
    00749
    00750   template<typename _CharT, typename _Traits, typename _Alloc>
    00751     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00752     basic_string<_CharT, _Traits, _Alloc>::
    00753     rfind(const _CharT* __s, size_type __pos, size_type __n) const
    00754     {
    00755       __glibcxx_requires_string_len(__s, __n);
    00756       const size_type __size = this->size();
    00757       if (__n <= __size)
    00758     {
    00759       __pos = std::min(size_type(__size - __n), __pos);
    00760       const _CharT* __data = _M_data();
    00761       do
    00762         {
    00763           if (traits_type::compare(__data + __pos, __s, __n) == 0)
    00764         return __pos;
    00765         }
    00766       while (__pos-- > 0);
    00767     }
    00768       return npos;
    00769     }
    00770
    00771   template<typename _CharT, typename _Traits, typename _Alloc>
    00772     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00773     basic_string<_CharT, _Traits, _Alloc>::
    00774     rfind(_CharT __c, size_type __pos) const
    00775     {
    00776       size_type __size = this->size();
    00777       if (__size)
    00778     {
    00779       if (--__size > __pos)
    00780         __size = __pos;
    00781       for (++__size; __size-- > 0; )
    00782         if (traits_type::eq(_M_data()[__size], __c))
    00783           return __size;
    00784     }
    00785       return npos;
    00786     }
    00787
    00788   template<typename _CharT, typename _Traits, typename _Alloc>
    00789     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00790     basic_string<_CharT, _Traits, _Alloc>::
    00791     find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
    00792     {
    00793       __glibcxx_requires_string_len(__s, __n);
    00794       for (; __n && __pos < this->size(); ++__pos)
    00795     {
    00796       const _CharT* __p = traits_type::find(__s, __n, _M_data()[__pos]);
    00797       if (__p)
    00798         return __pos;
    00799     }
    00800       return npos;
    00801     }
    00802
    00803   template<typename _CharT, typename _Traits, typename _Alloc>
    00804     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00805     basic_string<_CharT, _Traits, _Alloc>::
    00806     find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
    00807     {
    00808       __glibcxx_requires_string_len(__s, __n);
    00809       size_type __size = this->size();
    00810       if (__size && __n)
    00811     {
    00812       if (--__size > __pos)
    00813         __size = __pos;
    00814       do
    00815         {
    00816           if (traits_type::find(__s, __n, _M_data()[__size]))
    00817         return __size;
    00818         }
    00819       while (__size-- != 0);
    00820     }
    00821       return npos;
    00822     }
    00823
    00824   template<typename _CharT, typename _Traits, typename _Alloc>
    00825     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00826     basic_string<_CharT, _Traits, _Alloc>::
    00827     find_first_not_of(const _CharT* __s, size_type __pos, size_type __n) const
    00828     {
    00829       __glibcxx_requires_string_len(__s, __n);
    00830       for (; __pos < this->size(); ++__pos)
    00831     if (!traits_type::find(__s, __n, _M_data()[__pos]))
    00832       return __pos;
    00833       return npos;
    00834     }
    00835
    00836   template<typename _CharT, typename _Traits, typename _Alloc>
    00837     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00838     basic_string<_CharT, _Traits, _Alloc>::
    00839     find_first_not_of(_CharT __c, size_type __pos) const
    00840     {
    00841       for (; __pos < this->size(); ++__pos)
    00842     if (!traits_type::eq(_M_data()[__pos], __c))
    00843       return __pos;
    00844       return npos;
    00845     }
    00846
    00847   template<typename _CharT, typename _Traits, typename _Alloc>
    00848     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00849     basic_string<_CharT, _Traits, _Alloc>::
    00850     find_last_not_of(const _CharT* __s, size_type __pos, size_type __n) const
    00851     {
    00852       __glibcxx_requires_string_len(__s, __n);
    00853       size_type __size = this->size();
    00854       if (__size)
    00855     {
    00856       if (--__size > __pos)
    00857         __size = __pos;
    00858       do
    00859         {
    00860           if (!traits_type::find(__s, __n, _M_data()[__size]))
    00861         return __size;
    00862         }
    00863       while (__size--);
    00864     }
    00865       return npos;
    00866     }
    00867
    00868   template<typename _CharT, typename _Traits, typename _Alloc>
    00869     typename basic_string<_CharT, _Traits, _Alloc>::size_type
    00870     basic_string<_CharT, _Traits, _Alloc>::
    00871     find_last_not_of(_CharT __c, size_type __pos) const
    00872     {
    00873       size_type __size = this->size();
    00874       if (__size)
    00875     {
    00876       if (--__size > __pos)
    00877         __size = __pos;
    00878       do
    00879         {
    00880           if (!traits_type::eq(_M_data()[__size], __c))
    00881         return __size;
    00882         }
    00883       while (__size--);
    00884     }
    00885       return npos;
    00886     }
    00887
    00888   template<typename _CharT, typename _Traits, typename _Alloc>
    00889     int
    00890     basic_string<_CharT, _Traits, _Alloc>::
    00891     compare(size_type __pos, size_type __n, const basic_string& __str) const
    00892     {
    00893       _M_check(__pos, "basic_string::compare");
    00894       __n = _M_limit(__pos, __n);
    00895       const size_type __osize = __str.size();
    00896       const size_type __len = std::min(__n, __osize);
    00897       int __r = traits_type::compare(_M_data() + __pos, __str.data(), __len);
    00898       if (!__r)
    00899     __r = _S_compare(__n, __osize);
    00900       return __r;
    00901     }
    00902
    00903   template<typename _CharT, typename _Traits, typename _Alloc>
    00904     int
    00905     basic_string<_CharT, _Traits, _Alloc>::
    00906     compare(size_type __pos1, size_type __n1, const basic_string& __str,
    00907         size_type __pos2, size_type __n2) const
    00908     {
    00909       _M_check(__pos1, "basic_string::compare");
    00910       __str._M_check(__pos2, "basic_string::compare");
    00911       __n1 = _M_limit(__pos1, __n1);
    00912       __n2 = __str._M_limit(__pos2, __n2);
    00913       const size_type __len = std::min(__n1, __n2);
    00914       int __r = traits_type::compare(_M_data() + __pos1,
    00915                      __str.data() + __pos2, __len);
    00916       if (!__r)
    00917     __r = _S_compare(__n1, __n2);
    00918       return __r;
    00919     }
    00920
    00921   template<typename _CharT, typename _Traits, typename _Alloc>
    00922     int
    00923     basic_string<_CharT, _Traits, _Alloc>::
    00924     compare(const _CharT* __s) const
    00925     {
    00926       __glibcxx_requires_string(__s);
    00927       const size_type __size = this->size();
    00928       const size_type __osize = traits_type::length(__s);
    00929       const size_type __len = std::min(__size, __osize);
    00930       int __r = traits_type::compare(_M_data(), __s, __len);
    00931       if (!__r)
    00932     __r = _S_compare(__size, __osize);
    00933       return __r;
    00934     }
    00935
    00936   template<typename _CharT, typename _Traits, typename _Alloc>
    00937     int
    00938     basic_string <_CharT, _Traits, _Alloc>::
    00939     compare(size_type __pos, size_type __n1, const _CharT* __s) const
    00940     {
    00941       __glibcxx_requires_string(__s);
    00942       _M_check(__pos, "basic_string::compare");
    00943       __n1 = _M_limit(__pos, __n1);
    00944       const size_type __osize = traits_type::length(__s);
    00945       const size_type __len = std::min(__n1, __osize);
    00946       int __r = traits_type::compare(_M_data() + __pos, __s, __len);
    00947       if (!__r)
    00948     __r = _S_compare(__n1, __osize);
    00949       return __r;
    00950     }
    00951
    00952   template<typename _CharT, typename _Traits, typename _Alloc>
    00953     int
    00954     basic_string <_CharT, _Traits, _Alloc>::
    00955     compare(size_type __pos, size_type __n1, const _CharT* __s,
    00956         size_type __n2) const
    00957     {
    00958       __glibcxx_requires_string_len(__s, __n2);
    00959       _M_check(__pos, "basic_string::compare");
    00960       __n1 = _M_limit(__pos, __n1);
    00961       const size_type __len = std::min(__n1, __n2);
    00962       int __r = traits_type::compare(_M_data() + __pos, __s, __len);
    00963       if (!__r)
    00964     __r = _S_compare(__n1, __n2);
    00965       return __r;
    00966     }
    00967
    00968   // 21.3.7.9 basic_string::getline and operators
    00969   template<typename _CharT, typename _Traits, typename _Alloc>
    00970     basic_istream<_CharT, _Traits>&
    00971     operator>>(basic_istream<_CharT, _Traits>& __in,
    00972            basic_string<_CharT, _Traits, _Alloc>& __str)
    00973     {
    00974       typedef basic_istream<_CharT, _Traits>        __istream_type;
    00975       typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
    00976       typedef typename __istream_type::ios_base         __ios_base;
    00977       typedef typename __istream_type::int_type     __int_type;
    00978       typedef typename __string_type::size_type     __size_type;
    00979       typedef ctype<_CharT>             __ctype_type;
    00980       typedef typename __ctype_type::ctype_base         __ctype_base;
    00981
    00982       __size_type __extracted = 0;
    00983       typename __ios_base::iostate __err = __ios_base::goodbit;
    00984       typename __istream_type::sentry __cerb(__in, false);
    00985       if (__cerb)
    00986     {
    00987       try
    00988         {
    00989           // Avoid reallocation for common case.
    00990           __str.erase();
    00991           _CharT __buf[128];
    00992           __size_type __len = 0;
    00993           const streamsize __w = __in.width();
    00994           const __size_type __n = __w > 0 ? static_cast<__size_type>(__w)
    00995                                       : __str.max_size();
    00996           const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
    00997           const __int_type __eof = _Traits::eof();
    00998           __int_type __c = __in.rdbuf()->sgetc();
    00999
    01000           while (__extracted < __n
    01001              && !_Traits::eq_int_type(__c, __eof)
    01002              && !__ct.is(__ctype_base::space,
    01003                  _Traits::to_char_type(__c)))
    01004         {
    01005           if (__len == sizeof(__buf) / sizeof(_CharT))
    01006             {
    01007               __str.append(__buf, sizeof(__buf) / sizeof(_CharT));
    01008               __len = 0;
    01009             }
    01010           __buf[__len++] = _Traits::to_char_type(__c);
    01011           ++__extracted;
    01012           __c = __in.rdbuf()->snextc();
    01013         }
    01014           __str.append(__buf, __len);
    01015
    01016           if (_Traits::eq_int_type(__c, __eof))
    01017         __err |= __ios_base::eofbit;
    01018           __in.width(0);
    01019         }
    01020       catch(__cxxabiv1::__forced_unwind&)
    01021         {
    01022           __in._M_setstate(__ios_base::badbit);
    01023           __throw_exception_again;
    01024         }
    01025       catch(...)
    01026         {
    01027           // _GLIBCXX_RESOLVE_LIB_DEFECTS
    01028           // 91. Description of operator>> and getline() for string<>
    01029           // might cause endless loop
    01030           __in._M_setstate(__ios_base::badbit);
    01031         }
    01032     }
    01033       // 211.  operator>>(istream&, string&) doesn't set failbit
    01034       if (!__extracted)
    01035     __err |= __ios_base::failbit;
    01036       if (__err)
    01037     __in.setstate(__err);
    01038       return __in;
    01039     }
    01040
    01041   template<typename _CharT, typename _Traits, typename _Alloc>
    01042     basic_istream<_CharT, _Traits>&
    01043     getline(basic_istream<_CharT, _Traits>& __in,
    01044         basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim)
    01045     {
    01046       typedef basic_istream<_CharT, _Traits>        __istream_type;
    01047       typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
    01048       typedef typename __istream_type::ios_base         __ios_base;
    01049       typedef typename __istream_type::int_type     __int_type;
    01050       typedef typename __string_type::size_type     __size_type;
    01051
    01052       __size_type __extracted = 0;
    01053       const __size_type __n = __str.max_size();
    01054       typename __ios_base::iostate __err = __ios_base::goodbit;
    01055       typename __istream_type::sentry __cerb(__in, true);
    01056       if (__cerb)
    01057     {
    01058       try
    01059         {
    01060           __str.erase();
    01061           const __int_type __idelim = _Traits::to_int_type(__delim);
    01062           const __int_type __eof = _Traits::eof();
    01063           __int_type __c = __in.rdbuf()->sgetc();
    01064
    01065           while (__extracted < __n
    01066              && !_Traits::eq_int_type(__c, __eof)
    01067              && !_Traits::eq_int_type(__c, __idelim))
    01068         {
    01069           __str += _Traits::to_char_type(__c);
    01070           ++__extracted;
    01071           __c = __in.rdbuf()->snextc();
    01072         }
    01073
    01074           if (_Traits::eq_int_type(__c, __eof))
    01075         __err |= __ios_base::eofbit;
    01076           else if (_Traits::eq_int_type(__c, __idelim))
    01077         {
    01078           ++__extracted;
    01079           __in.rdbuf()->sbumpc();
    01080         }
    01081           else
    01082         __err |= __ios_base::failbit;
    01083         }
    01084       catch(__cxxabiv1::__forced_unwind&)
    01085         {
    01086           __in._M_setstate(__ios_base::badbit);
    01087           __throw_exception_again;
    01088         }
    01089       catch(...)
    01090         {
    01091           // _GLIBCXX_RESOLVE_LIB_DEFECTS
    01092           // 91. Description of operator>> and getline() for string<>
    01093           // might cause endless loop
    01094           __in._M_setstate(__ios_base::badbit);
    01095         }
    01096     }
    01097       if (!__extracted)
    01098     __err |= __ios_base::failbit;
    01099       if (__err)
    01100     __in.setstate(__err);
    01101       return __in;
    01102     }
    01103
    01104   // Inhibit implicit instantiations for required instantiations,
    01105   // which are defined via explicit instantiations elsewhere.
    01106   // NB: This syntax is a GNU extension.
    01107 #if _GLIBCXX_EXTERN_TEMPLATE
    01108   extern template class basic_string<char>;
    01109   extern template
    01110     basic_istream<char>&
    01111     operator>>(basic_istream<char>&, string&);
    01112   extern template
    01113     basic_ostream<char>&
    01114     operator<<(basic_ostream<char>&, const string&);
    01115   extern template
    01116     basic_istream<char>&
    01117     getline(basic_istream<char>&, string&, char);
    01118   extern template
    01119     basic_istream<char>&
    01120     getline(basic_istream<char>&, string&);
    01121
    01122 #ifdef _GLIBCXX_USE_WCHAR_T
    01123   extern template class basic_string<wchar_t>;
    01124   extern template
    01125     basic_istream<wchar_t>&
    01126     operator>>(basic_istream<wchar_t>&, wstring&);
    01127   extern template
    01128     basic_ostream<wchar_t>&
    01129     operator<<(basic_ostream<wchar_t>&, const wstring&);
    01130   extern template
    01131     basic_istream<wchar_t>&
    01132     getline(basic_istream<wchar_t>&, wstring&, wchar_t);
    01133   extern template
    01134     basic_istream<wchar_t>&
    01135     getline(basic_istream<wchar_t>&, wstring&);
    01136 #endif
    01137 #endif
    01138
    01139 _GLIBCXX_END_NAMESPACE
    01140
    01141 #endif