1*f8a1b7d9SAlexander Kabaev // Reference-counted versatile string base -*- C++ -*-
2*f8a1b7d9SAlexander Kabaev
3*f8a1b7d9SAlexander Kabaev // Copyright (C) 2005, 2006 Free Software Foundation, Inc.
4*f8a1b7d9SAlexander Kabaev //
5*f8a1b7d9SAlexander Kabaev // This file is part of the GNU ISO C++ Library. This library is free
6*f8a1b7d9SAlexander Kabaev // software; you can redistribute it and/or modify it under the
7*f8a1b7d9SAlexander Kabaev // terms of the GNU General Public License as published by the
8*f8a1b7d9SAlexander Kabaev // Free Software Foundation; either version 2, or (at your option)
9*f8a1b7d9SAlexander Kabaev // any later version.
10*f8a1b7d9SAlexander Kabaev
11*f8a1b7d9SAlexander Kabaev // This library is distributed in the hope that it will be useful,
12*f8a1b7d9SAlexander Kabaev // but WITHOUT ANY WARRANTY; without even the implied warranty of
13*f8a1b7d9SAlexander Kabaev // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14*f8a1b7d9SAlexander Kabaev // GNU General Public License for more details.
15*f8a1b7d9SAlexander Kabaev
16*f8a1b7d9SAlexander Kabaev // You should have received a copy of the GNU General Public License along
17*f8a1b7d9SAlexander Kabaev // with this library; see the file COPYING. If not, write to the Free
18*f8a1b7d9SAlexander Kabaev // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
19*f8a1b7d9SAlexander Kabaev // USA.
20*f8a1b7d9SAlexander Kabaev
21*f8a1b7d9SAlexander Kabaev // As a special exception, you may use this file as part of a free software
22*f8a1b7d9SAlexander Kabaev // library without restriction. Specifically, if other files instantiate
23*f8a1b7d9SAlexander Kabaev // templates or use macros or inline functions from this file, or you compile
24*f8a1b7d9SAlexander Kabaev // this file and link it with other files to produce an executable, this
25*f8a1b7d9SAlexander Kabaev // file does not by itself cause the resulting executable to be covered by
26*f8a1b7d9SAlexander Kabaev // the GNU General Public License. This exception does not however
27*f8a1b7d9SAlexander Kabaev // invalidate any other reasons why the executable file might be covered by
28*f8a1b7d9SAlexander Kabaev // the GNU General Public License.
29*f8a1b7d9SAlexander Kabaev
30*f8a1b7d9SAlexander Kabaev /** @file ext/rc_string_base.h
31*f8a1b7d9SAlexander Kabaev * This file is a GNU extension to the Standard C++ Library.
32*f8a1b7d9SAlexander Kabaev * This is an internal header file, included by other library headers.
33*f8a1b7d9SAlexander Kabaev * You should not attempt to use it directly.
34*f8a1b7d9SAlexander Kabaev */
35*f8a1b7d9SAlexander Kabaev
36*f8a1b7d9SAlexander Kabaev #ifndef _RC_STRING_BASE_H
37*f8a1b7d9SAlexander Kabaev #define _RC_STRING_BASE_H 1
38*f8a1b7d9SAlexander Kabaev
39*f8a1b7d9SAlexander Kabaev #include <ext/atomicity.h>
40*f8a1b7d9SAlexander Kabaev
_GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)41*f8a1b7d9SAlexander Kabaev _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
42*f8a1b7d9SAlexander Kabaev
43*f8a1b7d9SAlexander Kabaev /**
44*f8a1b7d9SAlexander Kabaev * @if maint
45*f8a1b7d9SAlexander Kabaev * Documentation? What's that?
46*f8a1b7d9SAlexander Kabaev * Nathan Myers <[email protected]>.
47*f8a1b7d9SAlexander Kabaev *
48*f8a1b7d9SAlexander Kabaev * A string looks like this:
49*f8a1b7d9SAlexander Kabaev *
50*f8a1b7d9SAlexander Kabaev * @code
51*f8a1b7d9SAlexander Kabaev * [_Rep]
52*f8a1b7d9SAlexander Kabaev * _M_length
53*f8a1b7d9SAlexander Kabaev * [__rc_string_base<char_type>] _M_capacity
54*f8a1b7d9SAlexander Kabaev * _M_dataplus _M_refcount
55*f8a1b7d9SAlexander Kabaev * _M_p ----------------> unnamed array of char_type
56*f8a1b7d9SAlexander Kabaev * @endcode
57*f8a1b7d9SAlexander Kabaev *
58*f8a1b7d9SAlexander Kabaev * Where the _M_p points to the first character in the string, and
59*f8a1b7d9SAlexander Kabaev * you cast it to a pointer-to-_Rep and subtract 1 to get a
60*f8a1b7d9SAlexander Kabaev * pointer to the header.
61*f8a1b7d9SAlexander Kabaev *
62*f8a1b7d9SAlexander Kabaev * This approach has the enormous advantage that a string object
63*f8a1b7d9SAlexander Kabaev * requires only one allocation. All the ugliness is confined
64*f8a1b7d9SAlexander Kabaev * within a single pair of inline functions, which each compile to
65*f8a1b7d9SAlexander Kabaev * a single "add" instruction: _Rep::_M_refdata(), and
66*f8a1b7d9SAlexander Kabaev * __rc_string_base::_M_rep(); and the allocation function which gets a
67*f8a1b7d9SAlexander Kabaev * block of raw bytes and with room enough and constructs a _Rep
68*f8a1b7d9SAlexander Kabaev * object at the front.
69*f8a1b7d9SAlexander Kabaev *
70*f8a1b7d9SAlexander Kabaev * The reason you want _M_data pointing to the character array and
71*f8a1b7d9SAlexander Kabaev * not the _Rep is so that the debugger can see the string
72*f8a1b7d9SAlexander Kabaev * contents. (Probably we should add a non-inline member to get
73*f8a1b7d9SAlexander Kabaev * the _Rep for the debugger to use, so users can check the actual
74*f8a1b7d9SAlexander Kabaev * string length.)
75*f8a1b7d9SAlexander Kabaev *
76*f8a1b7d9SAlexander Kabaev * Note that the _Rep object is a POD so that you can have a
77*f8a1b7d9SAlexander Kabaev * static "empty string" _Rep object already "constructed" before
78*f8a1b7d9SAlexander Kabaev * static constructors have run. The reference-count encoding is
79*f8a1b7d9SAlexander Kabaev * chosen so that a 0 indicates one reference, so you never try to
80*f8a1b7d9SAlexander Kabaev * destroy the empty-string _Rep object.
81*f8a1b7d9SAlexander Kabaev *
82*f8a1b7d9SAlexander Kabaev * All but the last paragraph is considered pretty conventional
83*f8a1b7d9SAlexander Kabaev * for a C++ string implementation.
84*f8a1b7d9SAlexander Kabaev * @endif
85*f8a1b7d9SAlexander Kabaev */
86*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
87*f8a1b7d9SAlexander Kabaev class __rc_string_base
88*f8a1b7d9SAlexander Kabaev : protected __vstring_utility<_CharT, _Traits, _Alloc>
89*f8a1b7d9SAlexander Kabaev {
90*f8a1b7d9SAlexander Kabaev public:
91*f8a1b7d9SAlexander Kabaev typedef _Traits traits_type;
92*f8a1b7d9SAlexander Kabaev typedef typename _Traits::char_type value_type;
93*f8a1b7d9SAlexander Kabaev typedef _Alloc allocator_type;
94*f8a1b7d9SAlexander Kabaev
95*f8a1b7d9SAlexander Kabaev typedef __vstring_utility<_CharT, _Traits, _Alloc> _Util_Base;
96*f8a1b7d9SAlexander Kabaev typedef typename _Util_Base::_CharT_alloc_type _CharT_alloc_type;
97*f8a1b7d9SAlexander Kabaev typedef typename _CharT_alloc_type::size_type size_type;
98*f8a1b7d9SAlexander Kabaev
99*f8a1b7d9SAlexander Kabaev private:
100*f8a1b7d9SAlexander Kabaev // _Rep: string representation
101*f8a1b7d9SAlexander Kabaev // Invariants:
102*f8a1b7d9SAlexander Kabaev // 1. String really contains _M_length + 1 characters: due to 21.3.4
103*f8a1b7d9SAlexander Kabaev // must be kept null-terminated.
104*f8a1b7d9SAlexander Kabaev // 2. _M_capacity >= _M_length
105*f8a1b7d9SAlexander Kabaev // Allocated memory is always (_M_capacity + 1) * sizeof(_CharT).
106*f8a1b7d9SAlexander Kabaev // 3. _M_refcount has three states:
107*f8a1b7d9SAlexander Kabaev // -1: leaked, one reference, no ref-copies allowed, non-const.
108*f8a1b7d9SAlexander Kabaev // 0: one reference, non-const.
109*f8a1b7d9SAlexander Kabaev // n>0: n + 1 references, operations require a lock, const.
110*f8a1b7d9SAlexander Kabaev // 4. All fields == 0 is an empty string, given the extra storage
111*f8a1b7d9SAlexander Kabaev // beyond-the-end for a null terminator; thus, the shared
112*f8a1b7d9SAlexander Kabaev // empty string representation needs no constructor.
113*f8a1b7d9SAlexander Kabaev struct _Rep
114*f8a1b7d9SAlexander Kabaev {
115*f8a1b7d9SAlexander Kabaev union
116*f8a1b7d9SAlexander Kabaev {
117*f8a1b7d9SAlexander Kabaev struct
118*f8a1b7d9SAlexander Kabaev {
119*f8a1b7d9SAlexander Kabaev size_type _M_length;
120*f8a1b7d9SAlexander Kabaev size_type _M_capacity;
121*f8a1b7d9SAlexander Kabaev _Atomic_word _M_refcount;
122*f8a1b7d9SAlexander Kabaev } _M_info;
123*f8a1b7d9SAlexander Kabaev
124*f8a1b7d9SAlexander Kabaev // Only for alignment purposes.
125*f8a1b7d9SAlexander Kabaev _CharT _M_align;
126*f8a1b7d9SAlexander Kabaev };
127*f8a1b7d9SAlexander Kabaev
128*f8a1b7d9SAlexander Kabaev typedef typename _Alloc::template rebind<_Rep>::other _Rep_alloc_type;
129*f8a1b7d9SAlexander Kabaev
130*f8a1b7d9SAlexander Kabaev _CharT*
131*f8a1b7d9SAlexander Kabaev _M_refdata() throw()
132*f8a1b7d9SAlexander Kabaev { return reinterpret_cast<_CharT*>(this + 1); }
133*f8a1b7d9SAlexander Kabaev
134*f8a1b7d9SAlexander Kabaev _CharT*
135*f8a1b7d9SAlexander Kabaev _M_refcopy() throw()
136*f8a1b7d9SAlexander Kabaev {
137*f8a1b7d9SAlexander Kabaev __atomic_add_dispatch(&_M_info._M_refcount, 1);
138*f8a1b7d9SAlexander Kabaev return _M_refdata();
139*f8a1b7d9SAlexander Kabaev } // XXX MT
140*f8a1b7d9SAlexander Kabaev
141*f8a1b7d9SAlexander Kabaev void
142*f8a1b7d9SAlexander Kabaev _M_set_length(size_type __n)
143*f8a1b7d9SAlexander Kabaev {
144*f8a1b7d9SAlexander Kabaev _M_info._M_refcount = 0; // One reference.
145*f8a1b7d9SAlexander Kabaev _M_info._M_length = __n;
146*f8a1b7d9SAlexander Kabaev // grrr. (per 21.3.4)
147*f8a1b7d9SAlexander Kabaev // You cannot leave those LWG people alone for a second.
148*f8a1b7d9SAlexander Kabaev traits_type::assign(_M_refdata()[__n], _CharT());
149*f8a1b7d9SAlexander Kabaev }
150*f8a1b7d9SAlexander Kabaev
151*f8a1b7d9SAlexander Kabaev // Create & Destroy
152*f8a1b7d9SAlexander Kabaev static _Rep*
153*f8a1b7d9SAlexander Kabaev _S_create(size_type, size_type, const _Alloc&);
154*f8a1b7d9SAlexander Kabaev
155*f8a1b7d9SAlexander Kabaev void
156*f8a1b7d9SAlexander Kabaev _M_destroy(const _Alloc&) throw();
157*f8a1b7d9SAlexander Kabaev
158*f8a1b7d9SAlexander Kabaev _CharT*
159*f8a1b7d9SAlexander Kabaev _M_clone(const _Alloc&, size_type __res = 0);
160*f8a1b7d9SAlexander Kabaev };
161*f8a1b7d9SAlexander Kabaev
162*f8a1b7d9SAlexander Kabaev struct _Rep_empty
163*f8a1b7d9SAlexander Kabaev : public _Rep
164*f8a1b7d9SAlexander Kabaev {
165*f8a1b7d9SAlexander Kabaev _CharT _M_terminal;
166*f8a1b7d9SAlexander Kabaev };
167*f8a1b7d9SAlexander Kabaev
168*f8a1b7d9SAlexander Kabaev static _Rep_empty _S_empty_rep;
169*f8a1b7d9SAlexander Kabaev
170*f8a1b7d9SAlexander Kabaev // The maximum number of individual char_type elements of an
171*f8a1b7d9SAlexander Kabaev // individual string is determined by _S_max_size. This is the
172*f8a1b7d9SAlexander Kabaev // value that will be returned by max_size(). (Whereas npos
173*f8a1b7d9SAlexander Kabaev // is the maximum number of bytes the allocator can allocate.)
174*f8a1b7d9SAlexander Kabaev // If one was to divvy up the theoretical largest size string,
175*f8a1b7d9SAlexander Kabaev // with a terminating character and m _CharT elements, it'd
176*f8a1b7d9SAlexander Kabaev // look like this:
177*f8a1b7d9SAlexander Kabaev // npos = sizeof(_Rep) + (m * sizeof(_CharT)) + sizeof(_CharT)
178*f8a1b7d9SAlexander Kabaev // + sizeof(_Rep) - 1
179*f8a1b7d9SAlexander Kabaev // (NB: last two terms for rounding reasons, see _M_create below)
180*f8a1b7d9SAlexander Kabaev // Solving for m:
181*f8a1b7d9SAlexander Kabaev // m = ((npos - 2 * sizeof(_Rep) + 1) / sizeof(_CharT)) - 1
182*f8a1b7d9SAlexander Kabaev // In addition, this implementation halfs this amount.
183*f8a1b7d9SAlexander Kabaev enum { _S_max_size = (((static_cast<size_type>(-1) - 2 * sizeof(_Rep)
184*f8a1b7d9SAlexander Kabaev + 1) / sizeof(_CharT)) - 1) / 2 };
185*f8a1b7d9SAlexander Kabaev
186*f8a1b7d9SAlexander Kabaev // Data Member (private):
187*f8a1b7d9SAlexander Kabaev mutable typename _Util_Base::template _Alloc_hider<_Alloc> _M_dataplus;
188*f8a1b7d9SAlexander Kabaev
189*f8a1b7d9SAlexander Kabaev void
190*f8a1b7d9SAlexander Kabaev _M_data(_CharT* __p)
191*f8a1b7d9SAlexander Kabaev { _M_dataplus._M_p = __p; }
192*f8a1b7d9SAlexander Kabaev
193*f8a1b7d9SAlexander Kabaev _Rep*
194*f8a1b7d9SAlexander Kabaev _M_rep() const
195*f8a1b7d9SAlexander Kabaev { return &((reinterpret_cast<_Rep*>(_M_data()))[-1]); }
196*f8a1b7d9SAlexander Kabaev
197*f8a1b7d9SAlexander Kabaev _CharT*
198*f8a1b7d9SAlexander Kabaev _M_grab(const _Alloc& __alloc) const
199*f8a1b7d9SAlexander Kabaev {
200*f8a1b7d9SAlexander Kabaev return (!_M_is_leaked() && _M_get_allocator() == __alloc)
201*f8a1b7d9SAlexander Kabaev ? _M_rep()->_M_refcopy() : _M_rep()->_M_clone(__alloc);
202*f8a1b7d9SAlexander Kabaev }
203*f8a1b7d9SAlexander Kabaev
204*f8a1b7d9SAlexander Kabaev void
205*f8a1b7d9SAlexander Kabaev _M_dispose()
206*f8a1b7d9SAlexander Kabaev {
207*f8a1b7d9SAlexander Kabaev if (__exchange_and_add_dispatch(&_M_rep()->_M_info._M_refcount,
208*f8a1b7d9SAlexander Kabaev -1) <= 0)
209*f8a1b7d9SAlexander Kabaev _M_rep()->_M_destroy(_M_get_allocator());
210*f8a1b7d9SAlexander Kabaev } // XXX MT
211*f8a1b7d9SAlexander Kabaev
212*f8a1b7d9SAlexander Kabaev bool
213*f8a1b7d9SAlexander Kabaev _M_is_leaked() const
214*f8a1b7d9SAlexander Kabaev { return _M_rep()->_M_info._M_refcount < 0; }
215*f8a1b7d9SAlexander Kabaev
216*f8a1b7d9SAlexander Kabaev void
217*f8a1b7d9SAlexander Kabaev _M_set_sharable()
218*f8a1b7d9SAlexander Kabaev { _M_rep()->_M_info._M_refcount = 0; }
219*f8a1b7d9SAlexander Kabaev
220*f8a1b7d9SAlexander Kabaev void
221*f8a1b7d9SAlexander Kabaev _M_leak_hard();
222*f8a1b7d9SAlexander Kabaev
223*f8a1b7d9SAlexander Kabaev // _S_construct_aux is used to implement the 21.3.1 para 15 which
224*f8a1b7d9SAlexander Kabaev // requires special behaviour if _InIterator is an integral type
225*f8a1b7d9SAlexander Kabaev template<typename _InIterator>
226*f8a1b7d9SAlexander Kabaev static _CharT*
227*f8a1b7d9SAlexander Kabaev _S_construct_aux(_InIterator __beg, _InIterator __end,
228*f8a1b7d9SAlexander Kabaev const _Alloc& __a, std::__false_type)
229*f8a1b7d9SAlexander Kabaev {
230*f8a1b7d9SAlexander Kabaev typedef typename iterator_traits<_InIterator>::iterator_category _Tag;
231*f8a1b7d9SAlexander Kabaev return _S_construct(__beg, __end, __a, _Tag());
232*f8a1b7d9SAlexander Kabaev }
233*f8a1b7d9SAlexander Kabaev
234*f8a1b7d9SAlexander Kabaev template<typename _InIterator>
235*f8a1b7d9SAlexander Kabaev static _CharT*
236*f8a1b7d9SAlexander Kabaev _S_construct_aux(_InIterator __beg, _InIterator __end,
237*f8a1b7d9SAlexander Kabaev const _Alloc& __a, std::__true_type)
238*f8a1b7d9SAlexander Kabaev { return _S_construct(static_cast<size_type>(__beg),
239*f8a1b7d9SAlexander Kabaev static_cast<value_type>(__end), __a); }
240*f8a1b7d9SAlexander Kabaev
241*f8a1b7d9SAlexander Kabaev template<typename _InIterator>
242*f8a1b7d9SAlexander Kabaev static _CharT*
243*f8a1b7d9SAlexander Kabaev _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a)
244*f8a1b7d9SAlexander Kabaev {
245*f8a1b7d9SAlexander Kabaev typedef typename std::__is_integer<_InIterator>::__type _Integral;
246*f8a1b7d9SAlexander Kabaev return _S_construct_aux(__beg, __end, __a, _Integral());
247*f8a1b7d9SAlexander Kabaev }
248*f8a1b7d9SAlexander Kabaev
249*f8a1b7d9SAlexander Kabaev // For Input Iterators, used in istreambuf_iterators, etc.
250*f8a1b7d9SAlexander Kabaev template<typename _InIterator>
251*f8a1b7d9SAlexander Kabaev static _CharT*
252*f8a1b7d9SAlexander Kabaev _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
253*f8a1b7d9SAlexander Kabaev std::input_iterator_tag);
254*f8a1b7d9SAlexander Kabaev
255*f8a1b7d9SAlexander Kabaev // For forward_iterators up to random_access_iterators, used for
256*f8a1b7d9SAlexander Kabaev // string::iterator, _CharT*, etc.
257*f8a1b7d9SAlexander Kabaev template<typename _FwdIterator>
258*f8a1b7d9SAlexander Kabaev static _CharT*
259*f8a1b7d9SAlexander Kabaev _S_construct(_FwdIterator __beg, _FwdIterator __end, const _Alloc& __a,
260*f8a1b7d9SAlexander Kabaev std::forward_iterator_tag);
261*f8a1b7d9SAlexander Kabaev
262*f8a1b7d9SAlexander Kabaev static _CharT*
263*f8a1b7d9SAlexander Kabaev _S_construct(size_type __req, _CharT __c, const _Alloc& __a);
264*f8a1b7d9SAlexander Kabaev
265*f8a1b7d9SAlexander Kabaev public:
266*f8a1b7d9SAlexander Kabaev size_type
267*f8a1b7d9SAlexander Kabaev _M_max_size() const
268*f8a1b7d9SAlexander Kabaev { return size_type(_S_max_size); }
269*f8a1b7d9SAlexander Kabaev
270*f8a1b7d9SAlexander Kabaev _CharT*
271*f8a1b7d9SAlexander Kabaev _M_data() const
272*f8a1b7d9SAlexander Kabaev { return _M_dataplus._M_p; }
273*f8a1b7d9SAlexander Kabaev
274*f8a1b7d9SAlexander Kabaev size_type
275*f8a1b7d9SAlexander Kabaev _M_length() const
276*f8a1b7d9SAlexander Kabaev { return _M_rep()->_M_info._M_length; }
277*f8a1b7d9SAlexander Kabaev
278*f8a1b7d9SAlexander Kabaev size_type
279*f8a1b7d9SAlexander Kabaev _M_capacity() const
280*f8a1b7d9SAlexander Kabaev { return _M_rep()->_M_info._M_capacity; }
281*f8a1b7d9SAlexander Kabaev
282*f8a1b7d9SAlexander Kabaev bool
283*f8a1b7d9SAlexander Kabaev _M_is_shared() const
284*f8a1b7d9SAlexander Kabaev { return _M_rep()->_M_info._M_refcount > 0; }
285*f8a1b7d9SAlexander Kabaev
286*f8a1b7d9SAlexander Kabaev void
287*f8a1b7d9SAlexander Kabaev _M_set_leaked()
288*f8a1b7d9SAlexander Kabaev { _M_rep()->_M_info._M_refcount = -1; }
289*f8a1b7d9SAlexander Kabaev
290*f8a1b7d9SAlexander Kabaev void
291*f8a1b7d9SAlexander Kabaev _M_leak() // for use in begin() & non-const op[]
292*f8a1b7d9SAlexander Kabaev {
293*f8a1b7d9SAlexander Kabaev if (!_M_is_leaked())
294*f8a1b7d9SAlexander Kabaev _M_leak_hard();
295*f8a1b7d9SAlexander Kabaev }
296*f8a1b7d9SAlexander Kabaev
297*f8a1b7d9SAlexander Kabaev void
298*f8a1b7d9SAlexander Kabaev _M_set_length(size_type __n)
299*f8a1b7d9SAlexander Kabaev { _M_rep()->_M_set_length(__n); }
300*f8a1b7d9SAlexander Kabaev
301*f8a1b7d9SAlexander Kabaev __rc_string_base()
302*f8a1b7d9SAlexander Kabaev : _M_dataplus(_Alloc(), _S_empty_rep._M_refcopy()) { }
303*f8a1b7d9SAlexander Kabaev
304*f8a1b7d9SAlexander Kabaev __rc_string_base(const _Alloc& __a);
305*f8a1b7d9SAlexander Kabaev
306*f8a1b7d9SAlexander Kabaev __rc_string_base(const __rc_string_base& __rcs);
307*f8a1b7d9SAlexander Kabaev
308*f8a1b7d9SAlexander Kabaev __rc_string_base(size_type __n, _CharT __c, const _Alloc& __a);
309*f8a1b7d9SAlexander Kabaev
310*f8a1b7d9SAlexander Kabaev template<typename _InputIterator>
311*f8a1b7d9SAlexander Kabaev __rc_string_base(_InputIterator __beg, _InputIterator __end,
312*f8a1b7d9SAlexander Kabaev const _Alloc& __a);
313*f8a1b7d9SAlexander Kabaev
314*f8a1b7d9SAlexander Kabaev ~__rc_string_base()
315*f8a1b7d9SAlexander Kabaev { _M_dispose(); }
316*f8a1b7d9SAlexander Kabaev
317*f8a1b7d9SAlexander Kabaev allocator_type&
318*f8a1b7d9SAlexander Kabaev _M_get_allocator()
319*f8a1b7d9SAlexander Kabaev { return _M_dataplus; }
320*f8a1b7d9SAlexander Kabaev
321*f8a1b7d9SAlexander Kabaev const allocator_type&
322*f8a1b7d9SAlexander Kabaev _M_get_allocator() const
323*f8a1b7d9SAlexander Kabaev { return _M_dataplus; }
324*f8a1b7d9SAlexander Kabaev
325*f8a1b7d9SAlexander Kabaev void
326*f8a1b7d9SAlexander Kabaev _M_swap(__rc_string_base& __rcs);
327*f8a1b7d9SAlexander Kabaev
328*f8a1b7d9SAlexander Kabaev void
329*f8a1b7d9SAlexander Kabaev _M_assign(const __rc_string_base& __rcs);
330*f8a1b7d9SAlexander Kabaev
331*f8a1b7d9SAlexander Kabaev void
332*f8a1b7d9SAlexander Kabaev _M_reserve(size_type __res);
333*f8a1b7d9SAlexander Kabaev
334*f8a1b7d9SAlexander Kabaev void
335*f8a1b7d9SAlexander Kabaev _M_mutate(size_type __pos, size_type __len1, const _CharT* __s,
336*f8a1b7d9SAlexander Kabaev size_type __len2);
337*f8a1b7d9SAlexander Kabaev
338*f8a1b7d9SAlexander Kabaev void
339*f8a1b7d9SAlexander Kabaev _M_erase(size_type __pos, size_type __n);
340*f8a1b7d9SAlexander Kabaev
341*f8a1b7d9SAlexander Kabaev void
342*f8a1b7d9SAlexander Kabaev _M_clear()
343*f8a1b7d9SAlexander Kabaev { _M_erase(size_type(0), _M_length()); }
344*f8a1b7d9SAlexander Kabaev
345*f8a1b7d9SAlexander Kabaev bool
346*f8a1b7d9SAlexander Kabaev _M_compare(const __rc_string_base&) const
347*f8a1b7d9SAlexander Kabaev { return false; }
348*f8a1b7d9SAlexander Kabaev };
349*f8a1b7d9SAlexander Kabaev
350*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
351*f8a1b7d9SAlexander Kabaev typename __rc_string_base<_CharT, _Traits, _Alloc>::_Rep_empty
352*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::_S_empty_rep;
353*f8a1b7d9SAlexander Kabaev
354*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
355*f8a1b7d9SAlexander Kabaev typename __rc_string_base<_CharT, _Traits, _Alloc>::_Rep*
356*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::_Rep::
_S_create(size_type __capacity,size_type __old_capacity,const _Alloc & __alloc)357*f8a1b7d9SAlexander Kabaev _S_create(size_type __capacity, size_type __old_capacity,
358*f8a1b7d9SAlexander Kabaev const _Alloc& __alloc)
359*f8a1b7d9SAlexander Kabaev {
360*f8a1b7d9SAlexander Kabaev // _GLIBCXX_RESOLVE_LIB_DEFECTS
361*f8a1b7d9SAlexander Kabaev // 83. String::npos vs. string::max_size()
362*f8a1b7d9SAlexander Kabaev if (__capacity > size_type(_S_max_size))
363*f8a1b7d9SAlexander Kabaev std::__throw_length_error(__N("__rc_string_base::_Rep::_S_create"));
364*f8a1b7d9SAlexander Kabaev
365*f8a1b7d9SAlexander Kabaev // The standard places no restriction on allocating more memory
366*f8a1b7d9SAlexander Kabaev // than is strictly needed within this layer at the moment or as
367*f8a1b7d9SAlexander Kabaev // requested by an explicit application call to reserve().
368*f8a1b7d9SAlexander Kabaev
369*f8a1b7d9SAlexander Kabaev // Many malloc implementations perform quite poorly when an
370*f8a1b7d9SAlexander Kabaev // application attempts to allocate memory in a stepwise fashion
371*f8a1b7d9SAlexander Kabaev // growing each allocation size by only 1 char. Additionally,
372*f8a1b7d9SAlexander Kabaev // it makes little sense to allocate less linear memory than the
373*f8a1b7d9SAlexander Kabaev // natural blocking size of the malloc implementation.
374*f8a1b7d9SAlexander Kabaev // Unfortunately, we would need a somewhat low-level calculation
375*f8a1b7d9SAlexander Kabaev // with tuned parameters to get this perfect for any particular
376*f8a1b7d9SAlexander Kabaev // malloc implementation. Fortunately, generalizations about
377*f8a1b7d9SAlexander Kabaev // common features seen among implementations seems to suffice.
378*f8a1b7d9SAlexander Kabaev
379*f8a1b7d9SAlexander Kabaev // __pagesize need not match the actual VM page size for good
380*f8a1b7d9SAlexander Kabaev // results in practice, thus we pick a common value on the low
381*f8a1b7d9SAlexander Kabaev // side. __malloc_header_size is an estimate of the amount of
382*f8a1b7d9SAlexander Kabaev // overhead per memory allocation (in practice seen N * sizeof
383*f8a1b7d9SAlexander Kabaev // (void*) where N is 0, 2 or 4). According to folklore,
384*f8a1b7d9SAlexander Kabaev // picking this value on the high side is better than
385*f8a1b7d9SAlexander Kabaev // low-balling it (especially when this algorithm is used with
386*f8a1b7d9SAlexander Kabaev // malloc implementations that allocate memory blocks rounded up
387*f8a1b7d9SAlexander Kabaev // to a size which is a power of 2).
388*f8a1b7d9SAlexander Kabaev const size_type __pagesize = 4096;
389*f8a1b7d9SAlexander Kabaev const size_type __malloc_header_size = 4 * sizeof(void*);
390*f8a1b7d9SAlexander Kabaev
391*f8a1b7d9SAlexander Kabaev // The below implements an exponential growth policy, necessary to
392*f8a1b7d9SAlexander Kabaev // meet amortized linear time requirements of the library: see
393*f8a1b7d9SAlexander Kabaev // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
394*f8a1b7d9SAlexander Kabaev if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
395*f8a1b7d9SAlexander Kabaev {
396*f8a1b7d9SAlexander Kabaev __capacity = 2 * __old_capacity;
397*f8a1b7d9SAlexander Kabaev // Never allocate a string bigger than _S_max_size.
398*f8a1b7d9SAlexander Kabaev if (__capacity > size_type(_S_max_size))
399*f8a1b7d9SAlexander Kabaev __capacity = size_type(_S_max_size);
400*f8a1b7d9SAlexander Kabaev }
401*f8a1b7d9SAlexander Kabaev
402*f8a1b7d9SAlexander Kabaev // NB: Need an array of char_type[__capacity], plus a terminating
403*f8a1b7d9SAlexander Kabaev // null char_type() element, plus enough for the _Rep data structure,
404*f8a1b7d9SAlexander Kabaev // plus sizeof(_Rep) - 1 to upper round to a size multiple of
405*f8a1b7d9SAlexander Kabaev // sizeof(_Rep).
406*f8a1b7d9SAlexander Kabaev // Whew. Seemingly so needy, yet so elemental.
407*f8a1b7d9SAlexander Kabaev size_type __size = ((__capacity + 1) * sizeof(_CharT)
408*f8a1b7d9SAlexander Kabaev + 2 * sizeof(_Rep) - 1);
409*f8a1b7d9SAlexander Kabaev
410*f8a1b7d9SAlexander Kabaev const size_type __adj_size = __size + __malloc_header_size;
411*f8a1b7d9SAlexander Kabaev if (__adj_size > __pagesize && __capacity > __old_capacity)
412*f8a1b7d9SAlexander Kabaev {
413*f8a1b7d9SAlexander Kabaev const size_type __extra = __pagesize - __adj_size % __pagesize;
414*f8a1b7d9SAlexander Kabaev __capacity += __extra / sizeof(_CharT);
415*f8a1b7d9SAlexander Kabaev if (__capacity > size_type(_S_max_size))
416*f8a1b7d9SAlexander Kabaev __capacity = size_type(_S_max_size);
417*f8a1b7d9SAlexander Kabaev __size = (__capacity + 1) * sizeof(_CharT) + 2 * sizeof(_Rep) - 1;
418*f8a1b7d9SAlexander Kabaev }
419*f8a1b7d9SAlexander Kabaev
420*f8a1b7d9SAlexander Kabaev // NB: Might throw, but no worries about a leak, mate: _Rep()
421*f8a1b7d9SAlexander Kabaev // does not throw.
422*f8a1b7d9SAlexander Kabaev _Rep* __place = _Rep_alloc_type(__alloc).allocate(__size / sizeof(_Rep));
423*f8a1b7d9SAlexander Kabaev _Rep* __p = new (__place) _Rep;
424*f8a1b7d9SAlexander Kabaev __p->_M_info._M_capacity = __capacity;
425*f8a1b7d9SAlexander Kabaev return __p;
426*f8a1b7d9SAlexander Kabaev }
427*f8a1b7d9SAlexander Kabaev
428*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
429*f8a1b7d9SAlexander Kabaev void
430*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::_Rep::
_M_destroy(const _Alloc & __a)431*f8a1b7d9SAlexander Kabaev _M_destroy(const _Alloc& __a) throw ()
432*f8a1b7d9SAlexander Kabaev {
433*f8a1b7d9SAlexander Kabaev const size_type __size = ((_M_info._M_capacity + 1) * sizeof(_CharT)
434*f8a1b7d9SAlexander Kabaev + 2 * sizeof(_Rep) - 1);
435*f8a1b7d9SAlexander Kabaev _Rep_alloc_type(__a).deallocate(this, __size / sizeof(_Rep));
436*f8a1b7d9SAlexander Kabaev }
437*f8a1b7d9SAlexander Kabaev
438*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
439*f8a1b7d9SAlexander Kabaev _CharT*
440*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::_Rep::
_M_clone(const _Alloc & __alloc,size_type __res)441*f8a1b7d9SAlexander Kabaev _M_clone(const _Alloc& __alloc, size_type __res)
442*f8a1b7d9SAlexander Kabaev {
443*f8a1b7d9SAlexander Kabaev // Requested capacity of the clone.
444*f8a1b7d9SAlexander Kabaev const size_type __requested_cap = _M_info._M_length + __res;
445*f8a1b7d9SAlexander Kabaev _Rep* __r = _Rep::_S_create(__requested_cap, _M_info._M_capacity,
446*f8a1b7d9SAlexander Kabaev __alloc);
447*f8a1b7d9SAlexander Kabaev
448*f8a1b7d9SAlexander Kabaev if (_M_info._M_length)
449*f8a1b7d9SAlexander Kabaev _S_copy(__r->_M_refdata(), _M_refdata(), _M_info._M_length);
450*f8a1b7d9SAlexander Kabaev
451*f8a1b7d9SAlexander Kabaev __r->_M_set_length(_M_info._M_length);
452*f8a1b7d9SAlexander Kabaev return __r->_M_refdata();
453*f8a1b7d9SAlexander Kabaev }
454*f8a1b7d9SAlexander Kabaev
455*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
456*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
__rc_string_base(const _Alloc & __a)457*f8a1b7d9SAlexander Kabaev __rc_string_base(const _Alloc& __a)
458*f8a1b7d9SAlexander Kabaev : _M_dataplus(__a, _S_construct(size_type(), _CharT(), __a)) { }
459*f8a1b7d9SAlexander Kabaev
460*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
461*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
__rc_string_base(const __rc_string_base & __rcs)462*f8a1b7d9SAlexander Kabaev __rc_string_base(const __rc_string_base& __rcs)
463*f8a1b7d9SAlexander Kabaev : _M_dataplus(__rcs._M_get_allocator(),
464*f8a1b7d9SAlexander Kabaev __rcs._M_grab(__rcs._M_get_allocator())) { }
465*f8a1b7d9SAlexander Kabaev
466*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
467*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
__rc_string_base(size_type __n,_CharT __c,const _Alloc & __a)468*f8a1b7d9SAlexander Kabaev __rc_string_base(size_type __n, _CharT __c, const _Alloc& __a)
469*f8a1b7d9SAlexander Kabaev : _M_dataplus(__a, _S_construct(__n, __c, __a)) { }
470*f8a1b7d9SAlexander Kabaev
471*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
472*f8a1b7d9SAlexander Kabaev template<typename _InputIterator>
473*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
__rc_string_base(_InputIterator __beg,_InputIterator __end,const _Alloc & __a)474*f8a1b7d9SAlexander Kabaev __rc_string_base(_InputIterator __beg, _InputIterator __end,
475*f8a1b7d9SAlexander Kabaev const _Alloc& __a)
476*f8a1b7d9SAlexander Kabaev : _M_dataplus(__a, _S_construct(__beg, __end, __a)) { }
477*f8a1b7d9SAlexander Kabaev
478*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
479*f8a1b7d9SAlexander Kabaev void
480*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
_M_leak_hard()481*f8a1b7d9SAlexander Kabaev _M_leak_hard()
482*f8a1b7d9SAlexander Kabaev {
483*f8a1b7d9SAlexander Kabaev if (_M_is_shared())
484*f8a1b7d9SAlexander Kabaev _M_erase(0, 0);
485*f8a1b7d9SAlexander Kabaev _M_set_leaked();
486*f8a1b7d9SAlexander Kabaev }
487*f8a1b7d9SAlexander Kabaev
488*f8a1b7d9SAlexander Kabaev // NB: This is the special case for Input Iterators, used in
489*f8a1b7d9SAlexander Kabaev // istreambuf_iterators, etc.
490*f8a1b7d9SAlexander Kabaev // Input Iterators have a cost structure very different from
491*f8a1b7d9SAlexander Kabaev // pointers, calling for a different coding style.
492*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
493*f8a1b7d9SAlexander Kabaev template<typename _InIterator>
494*f8a1b7d9SAlexander Kabaev _CharT*
495*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
_S_construct(_InIterator __beg,_InIterator __end,const _Alloc & __a,std::input_iterator_tag)496*f8a1b7d9SAlexander Kabaev _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
497*f8a1b7d9SAlexander Kabaev std::input_iterator_tag)
498*f8a1b7d9SAlexander Kabaev {
499*f8a1b7d9SAlexander Kabaev if (__beg == __end && __a == _Alloc())
500*f8a1b7d9SAlexander Kabaev return _S_empty_rep._M_refcopy();
501*f8a1b7d9SAlexander Kabaev
502*f8a1b7d9SAlexander Kabaev // Avoid reallocation for common case.
503*f8a1b7d9SAlexander Kabaev _CharT __buf[128];
504*f8a1b7d9SAlexander Kabaev size_type __len = 0;
505*f8a1b7d9SAlexander Kabaev while (__beg != __end && __len < sizeof(__buf) / sizeof(_CharT))
506*f8a1b7d9SAlexander Kabaev {
507*f8a1b7d9SAlexander Kabaev __buf[__len++] = *__beg;
508*f8a1b7d9SAlexander Kabaev ++__beg;
509*f8a1b7d9SAlexander Kabaev }
510*f8a1b7d9SAlexander Kabaev _Rep* __r = _Rep::_S_create(__len, size_type(0), __a);
511*f8a1b7d9SAlexander Kabaev _S_copy(__r->_M_refdata(), __buf, __len);
512*f8a1b7d9SAlexander Kabaev try
513*f8a1b7d9SAlexander Kabaev {
514*f8a1b7d9SAlexander Kabaev while (__beg != __end)
515*f8a1b7d9SAlexander Kabaev {
516*f8a1b7d9SAlexander Kabaev if (__len == __r->_M_info._M_capacity)
517*f8a1b7d9SAlexander Kabaev {
518*f8a1b7d9SAlexander Kabaev // Allocate more space.
519*f8a1b7d9SAlexander Kabaev _Rep* __another = _Rep::_S_create(__len + 1, __len, __a);
520*f8a1b7d9SAlexander Kabaev _S_copy(__another->_M_refdata(), __r->_M_refdata(), __len);
521*f8a1b7d9SAlexander Kabaev __r->_M_destroy(__a);
522*f8a1b7d9SAlexander Kabaev __r = __another;
523*f8a1b7d9SAlexander Kabaev }
524*f8a1b7d9SAlexander Kabaev __r->_M_refdata()[__len++] = *__beg;
525*f8a1b7d9SAlexander Kabaev ++__beg;
526*f8a1b7d9SAlexander Kabaev }
527*f8a1b7d9SAlexander Kabaev }
528*f8a1b7d9SAlexander Kabaev catch(...)
529*f8a1b7d9SAlexander Kabaev {
530*f8a1b7d9SAlexander Kabaev __r->_M_destroy(__a);
531*f8a1b7d9SAlexander Kabaev __throw_exception_again;
532*f8a1b7d9SAlexander Kabaev }
533*f8a1b7d9SAlexander Kabaev __r->_M_set_length(__len);
534*f8a1b7d9SAlexander Kabaev return __r->_M_refdata();
535*f8a1b7d9SAlexander Kabaev }
536*f8a1b7d9SAlexander Kabaev
537*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
538*f8a1b7d9SAlexander Kabaev template<typename _InIterator>
539*f8a1b7d9SAlexander Kabaev _CharT*
540*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
_S_construct(_InIterator __beg,_InIterator __end,const _Alloc & __a,std::forward_iterator_tag)541*f8a1b7d9SAlexander Kabaev _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
542*f8a1b7d9SAlexander Kabaev std::forward_iterator_tag)
543*f8a1b7d9SAlexander Kabaev {
544*f8a1b7d9SAlexander Kabaev if (__beg == __end && __a == _Alloc())
545*f8a1b7d9SAlexander Kabaev return _S_empty_rep._M_refcopy();
546*f8a1b7d9SAlexander Kabaev
547*f8a1b7d9SAlexander Kabaev // NB: Not required, but considered best practice.
548*f8a1b7d9SAlexander Kabaev if (__builtin_expect(_S_is_null_pointer(__beg) && __beg != __end, 0))
549*f8a1b7d9SAlexander Kabaev std::__throw_logic_error(__N("__rc_string_base::"
550*f8a1b7d9SAlexander Kabaev "_S_construct NULL not valid"));
551*f8a1b7d9SAlexander Kabaev
552*f8a1b7d9SAlexander Kabaev const size_type __dnew = static_cast<size_type>(std::distance(__beg,
553*f8a1b7d9SAlexander Kabaev __end));
554*f8a1b7d9SAlexander Kabaev // Check for out_of_range and length_error exceptions.
555*f8a1b7d9SAlexander Kabaev _Rep* __r = _Rep::_S_create(__dnew, size_type(0), __a);
556*f8a1b7d9SAlexander Kabaev try
557*f8a1b7d9SAlexander Kabaev { _S_copy_chars(__r->_M_refdata(), __beg, __end); }
558*f8a1b7d9SAlexander Kabaev catch(...)
559*f8a1b7d9SAlexander Kabaev {
560*f8a1b7d9SAlexander Kabaev __r->_M_destroy(__a);
561*f8a1b7d9SAlexander Kabaev __throw_exception_again;
562*f8a1b7d9SAlexander Kabaev }
563*f8a1b7d9SAlexander Kabaev __r->_M_set_length(__dnew);
564*f8a1b7d9SAlexander Kabaev return __r->_M_refdata();
565*f8a1b7d9SAlexander Kabaev }
566*f8a1b7d9SAlexander Kabaev
567*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
568*f8a1b7d9SAlexander Kabaev _CharT*
569*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
_S_construct(size_type __n,_CharT __c,const _Alloc & __a)570*f8a1b7d9SAlexander Kabaev _S_construct(size_type __n, _CharT __c, const _Alloc& __a)
571*f8a1b7d9SAlexander Kabaev {
572*f8a1b7d9SAlexander Kabaev if (__n == 0 && __a == _Alloc())
573*f8a1b7d9SAlexander Kabaev return _S_empty_rep._M_refcopy();
574*f8a1b7d9SAlexander Kabaev
575*f8a1b7d9SAlexander Kabaev // Check for out_of_range and length_error exceptions.
576*f8a1b7d9SAlexander Kabaev _Rep* __r = _Rep::_S_create(__n, size_type(0), __a);
577*f8a1b7d9SAlexander Kabaev if (__n)
578*f8a1b7d9SAlexander Kabaev _S_assign(__r->_M_refdata(), __n, __c);
579*f8a1b7d9SAlexander Kabaev
580*f8a1b7d9SAlexander Kabaev __r->_M_set_length(__n);
581*f8a1b7d9SAlexander Kabaev return __r->_M_refdata();
582*f8a1b7d9SAlexander Kabaev }
583*f8a1b7d9SAlexander Kabaev
584*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
585*f8a1b7d9SAlexander Kabaev void
586*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
_M_swap(__rc_string_base & __rcs)587*f8a1b7d9SAlexander Kabaev _M_swap(__rc_string_base& __rcs)
588*f8a1b7d9SAlexander Kabaev {
589*f8a1b7d9SAlexander Kabaev if (_M_is_leaked())
590*f8a1b7d9SAlexander Kabaev _M_set_sharable();
591*f8a1b7d9SAlexander Kabaev if (__rcs._M_is_leaked())
592*f8a1b7d9SAlexander Kabaev __rcs._M_set_sharable();
593*f8a1b7d9SAlexander Kabaev
594*f8a1b7d9SAlexander Kabaev _CharT* __tmp = _M_data();
595*f8a1b7d9SAlexander Kabaev _M_data(__rcs._M_data());
596*f8a1b7d9SAlexander Kabaev __rcs._M_data(__tmp);
597*f8a1b7d9SAlexander Kabaev
598*f8a1b7d9SAlexander Kabaev // _GLIBCXX_RESOLVE_LIB_DEFECTS
599*f8a1b7d9SAlexander Kabaev // 431. Swapping containers with unequal allocators.
600*f8a1b7d9SAlexander Kabaev std::__alloc_swap<allocator_type>::_S_do_it(_M_get_allocator(),
601*f8a1b7d9SAlexander Kabaev __rcs._M_get_allocator());
602*f8a1b7d9SAlexander Kabaev }
603*f8a1b7d9SAlexander Kabaev
604*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
605*f8a1b7d9SAlexander Kabaev void
606*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
_M_assign(const __rc_string_base & __rcs)607*f8a1b7d9SAlexander Kabaev _M_assign(const __rc_string_base& __rcs)
608*f8a1b7d9SAlexander Kabaev {
609*f8a1b7d9SAlexander Kabaev if (_M_rep() != __rcs._M_rep())
610*f8a1b7d9SAlexander Kabaev {
611*f8a1b7d9SAlexander Kabaev _CharT* __tmp = __rcs._M_grab(_M_get_allocator());
612*f8a1b7d9SAlexander Kabaev _M_dispose();
613*f8a1b7d9SAlexander Kabaev _M_data(__tmp);
614*f8a1b7d9SAlexander Kabaev }
615*f8a1b7d9SAlexander Kabaev }
616*f8a1b7d9SAlexander Kabaev
617*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
618*f8a1b7d9SAlexander Kabaev void
619*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
_M_reserve(size_type __res)620*f8a1b7d9SAlexander Kabaev _M_reserve(size_type __res)
621*f8a1b7d9SAlexander Kabaev {
622*f8a1b7d9SAlexander Kabaev // Make sure we don't shrink below the current size.
623*f8a1b7d9SAlexander Kabaev if (__res < _M_length())
624*f8a1b7d9SAlexander Kabaev __res = _M_length();
625*f8a1b7d9SAlexander Kabaev
626*f8a1b7d9SAlexander Kabaev if (__res != _M_capacity() || _M_is_shared())
627*f8a1b7d9SAlexander Kabaev {
628*f8a1b7d9SAlexander Kabaev _CharT* __tmp = _M_rep()->_M_clone(_M_get_allocator(),
629*f8a1b7d9SAlexander Kabaev __res - _M_length());
630*f8a1b7d9SAlexander Kabaev _M_dispose();
631*f8a1b7d9SAlexander Kabaev _M_data(__tmp);
632*f8a1b7d9SAlexander Kabaev }
633*f8a1b7d9SAlexander Kabaev }
634*f8a1b7d9SAlexander Kabaev
635*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
636*f8a1b7d9SAlexander Kabaev void
637*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
_M_mutate(size_type __pos,size_type __len1,const _CharT * __s,size_type __len2)638*f8a1b7d9SAlexander Kabaev _M_mutate(size_type __pos, size_type __len1, const _CharT* __s,
639*f8a1b7d9SAlexander Kabaev size_type __len2)
640*f8a1b7d9SAlexander Kabaev {
641*f8a1b7d9SAlexander Kabaev const size_type __how_much = _M_length() - __pos - __len1;
642*f8a1b7d9SAlexander Kabaev
643*f8a1b7d9SAlexander Kabaev _Rep* __r = _Rep::_S_create(_M_length() + __len2 - __len1,
644*f8a1b7d9SAlexander Kabaev _M_capacity(), _M_get_allocator());
645*f8a1b7d9SAlexander Kabaev
646*f8a1b7d9SAlexander Kabaev if (__pos)
647*f8a1b7d9SAlexander Kabaev _S_copy(__r->_M_refdata(), _M_data(), __pos);
648*f8a1b7d9SAlexander Kabaev if (__s && __len2)
649*f8a1b7d9SAlexander Kabaev _S_copy(__r->_M_refdata() + __pos, __s, __len2);
650*f8a1b7d9SAlexander Kabaev if (__how_much)
651*f8a1b7d9SAlexander Kabaev _S_copy(__r->_M_refdata() + __pos + __len2,
652*f8a1b7d9SAlexander Kabaev _M_data() + __pos + __len1, __how_much);
653*f8a1b7d9SAlexander Kabaev
654*f8a1b7d9SAlexander Kabaev _M_dispose();
655*f8a1b7d9SAlexander Kabaev _M_data(__r->_M_refdata());
656*f8a1b7d9SAlexander Kabaev }
657*f8a1b7d9SAlexander Kabaev
658*f8a1b7d9SAlexander Kabaev template<typename _CharT, typename _Traits, typename _Alloc>
659*f8a1b7d9SAlexander Kabaev void
660*f8a1b7d9SAlexander Kabaev __rc_string_base<_CharT, _Traits, _Alloc>::
_M_erase(size_type __pos,size_type __n)661*f8a1b7d9SAlexander Kabaev _M_erase(size_type __pos, size_type __n)
662*f8a1b7d9SAlexander Kabaev {
663*f8a1b7d9SAlexander Kabaev const size_type __new_size = _M_length() - __n;
664*f8a1b7d9SAlexander Kabaev const size_type __how_much = _M_length() - __pos - __n;
665*f8a1b7d9SAlexander Kabaev
666*f8a1b7d9SAlexander Kabaev if (_M_is_shared())
667*f8a1b7d9SAlexander Kabaev {
668*f8a1b7d9SAlexander Kabaev // Must reallocate.
669*f8a1b7d9SAlexander Kabaev _Rep* __r = _Rep::_S_create(__new_size, _M_capacity(),
670*f8a1b7d9SAlexander Kabaev _M_get_allocator());
671*f8a1b7d9SAlexander Kabaev
672*f8a1b7d9SAlexander Kabaev if (__pos)
673*f8a1b7d9SAlexander Kabaev _S_copy(__r->_M_refdata(), _M_data(), __pos);
674*f8a1b7d9SAlexander Kabaev if (__how_much)
675*f8a1b7d9SAlexander Kabaev _S_copy(__r->_M_refdata() + __pos,
676*f8a1b7d9SAlexander Kabaev _M_data() + __pos + __n, __how_much);
677*f8a1b7d9SAlexander Kabaev
678*f8a1b7d9SAlexander Kabaev _M_dispose();
679*f8a1b7d9SAlexander Kabaev _M_data(__r->_M_refdata());
680*f8a1b7d9SAlexander Kabaev }
681*f8a1b7d9SAlexander Kabaev else if (__how_much && __n)
682*f8a1b7d9SAlexander Kabaev {
683*f8a1b7d9SAlexander Kabaev // Work in-place.
684*f8a1b7d9SAlexander Kabaev _S_move(_M_data() + __pos,
685*f8a1b7d9SAlexander Kabaev _M_data() + __pos + __n, __how_much);
686*f8a1b7d9SAlexander Kabaev }
687*f8a1b7d9SAlexander Kabaev
688*f8a1b7d9SAlexander Kabaev _M_rep()->_M_set_length(__new_size);
689*f8a1b7d9SAlexander Kabaev }
690*f8a1b7d9SAlexander Kabaev
691*f8a1b7d9SAlexander Kabaev template<>
692*f8a1b7d9SAlexander Kabaev inline bool
693*f8a1b7d9SAlexander Kabaev __rc_string_base<char, std::char_traits<char>,
694*f8a1b7d9SAlexander Kabaev std::allocator<char> >::
_M_compare(const __rc_string_base & __rcs)695*f8a1b7d9SAlexander Kabaev _M_compare(const __rc_string_base& __rcs) const
696*f8a1b7d9SAlexander Kabaev {
697*f8a1b7d9SAlexander Kabaev if (_M_rep() == __rcs._M_rep())
698*f8a1b7d9SAlexander Kabaev return true;
699*f8a1b7d9SAlexander Kabaev return false;
700*f8a1b7d9SAlexander Kabaev }
701*f8a1b7d9SAlexander Kabaev
702*f8a1b7d9SAlexander Kabaev #ifdef _GLIBCXX_USE_WCHAR_T
703*f8a1b7d9SAlexander Kabaev template<>
704*f8a1b7d9SAlexander Kabaev inline bool
705*f8a1b7d9SAlexander Kabaev __rc_string_base<wchar_t, std::char_traits<wchar_t>,
706*f8a1b7d9SAlexander Kabaev std::allocator<wchar_t> >::
_M_compare(const __rc_string_base & __rcs)707*f8a1b7d9SAlexander Kabaev _M_compare(const __rc_string_base& __rcs) const
708*f8a1b7d9SAlexander Kabaev {
709*f8a1b7d9SAlexander Kabaev if (_M_rep() == __rcs._M_rep())
710*f8a1b7d9SAlexander Kabaev return true;
711*f8a1b7d9SAlexander Kabaev return false;
712*f8a1b7d9SAlexander Kabaev }
713*f8a1b7d9SAlexander Kabaev #endif
714*f8a1b7d9SAlexander Kabaev
715*f8a1b7d9SAlexander Kabaev _GLIBCXX_END_NAMESPACE
716*f8a1b7d9SAlexander Kabaev
717*f8a1b7d9SAlexander Kabaev #endif /* _RC_STRING_BASE_H */
718