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1 : : // Position types -*- C++ -*-
2 : :
3 : : // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
4 : : // 2006, 2007, 2008, 2009, 2010
5 : : // Free Software Foundation, Inc.
6 : : //
7 : : // This file is part of the GNU ISO C++ Library. This library is free
8 : : // software; you can redistribute it and/or modify it under the
9 : : // terms of the GNU General Public License as published by the
10 : : // Free Software Foundation; either version 3, or (at your option)
11 : : // any later version.
12 : :
13 : : // This library is distributed in the hope that it will be useful,
14 : : // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 : : // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 : : // GNU General Public License for more details.
17 : :
18 : : // Under Section 7 of GPL version 3, you are granted additional
19 : : // permissions described in the GCC Runtime Library Exception, version
20 : : // 3.1, as published by the Free Software Foundation.
21 : :
22 : : // You should have received a copy of the GNU General Public License and
23 : : // a copy of the GCC Runtime Library Exception along with this program;
24 : : // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
25 : : // <http://www.gnu.org/licenses/>.
26 : :
27 : : /** @file bits/postypes.h
28 : : * This is an internal header file, included by other library headers.
29 : : * Do not attempt to use it directly. @headername{iosfwd}
30 : : */
31 : :
32 : : //
33 : : // ISO C++ 14882: 27.4.1 - Types
34 : : // ISO C++ 14882: 27.4.3 - Template class fpos
35 : : //
36 : :
37 : : #ifndef _GLIBCXX_POSTYPES_H
38 : : #define _GLIBCXX_POSTYPES_H 1
39 : :
40 : : #pragma GCC system_header
41 : :
42 : : #include <cwchar> // For mbstate_t
43 : :
44 : : // XXX If <stdint.h> is really needed, make sure to define the macros
45 : : // before including it, in order not to break <tr1/cstdint> (and <cstdint>
46 : : // in C++0x). Reconsider all this as soon as possible...
47 : : #if (defined(_GLIBCXX_HAVE_INT64_T) && !defined(_GLIBCXX_HAVE_INT64_T_LONG) \
48 : : && !defined(_GLIBCXX_HAVE_INT64_T_LONG_LONG))
49 : :
50 : : #ifndef __STDC_LIMIT_MACROS
51 : : # define _UNDEF__STDC_LIMIT_MACROS
52 : : # define __STDC_LIMIT_MACROS
53 : : #endif
54 : : #ifndef __STDC_CONSTANT_MACROS
55 : : # define _UNDEF__STDC_CONSTANT_MACROS
56 : : # define __STDC_CONSTANT_MACROS
57 : : #endif
58 : : #include <stdint.h> // For int64_t
59 : : #ifdef _UNDEF__STDC_LIMIT_MACROS
60 : : # undef __STDC_LIMIT_MACROS
61 : : # undef _UNDEF__STDC_LIMIT_MACROS
62 : : #endif
63 : : #ifdef _UNDEF__STDC_CONSTANT_MACROS
64 : : # undef __STDC_CONSTANT_MACROS
65 : : # undef _UNDEF__STDC_CONSTANT_MACROS
66 : : #endif
67 : :
68 : : #endif
69 : :
70 : : namespace std _GLIBCXX_VISIBILITY(default)
71 : : {
72 : : _GLIBCXX_BEGIN_NAMESPACE_VERSION
73 : :
74 : : // The types streamoff, streampos and wstreampos and the class
75 : : // template fpos<> are described in clauses 21.1.2, 21.1.3, 27.1.2,
76 : : // 27.2, 27.4.1, 27.4.3 and D.6. Despite all this verbiage, the
77 : : // behaviour of these types is mostly implementation defined or
78 : : // unspecified. The behaviour in this implementation is as noted
79 : : // below.
80 : :
81 : : /**
82 : : * @brief Type used by fpos, char_traits<char>, and char_traits<wchar_t>.
83 : : *
84 : : * In clauses 21.1.3.1 and 27.4.1 streamoff is described as an
85 : : * implementation defined type.
86 : : * Note: In versions of GCC up to and including GCC 3.3, streamoff
87 : : * was typedef long.
88 : : */
89 : : #ifdef _GLIBCXX_HAVE_INT64_T_LONG
90 : : typedef long streamoff;
91 : : #elif defined(_GLIBCXX_HAVE_INT64_T_LONG_LONG)
92 : : typedef long long streamoff;
93 : : #elif defined(_GLIBCXX_HAVE_INT64_T)
94 : : typedef int64_t streamoff;
95 : : #else
96 : : typedef long long streamoff;
97 : : #endif
98 : :
99 : : /// Integral type for I/O operation counts and buffer sizes.
100 : : typedef ptrdiff_t streamsize; // Signed integral type
101 : :
102 : : /**
103 : : * @brief Class representing stream positions.
104 : : *
105 : : * The standard places no requirements upon the template parameter StateT.
106 : : * In this implementation StateT must be DefaultConstructible,
107 : : * CopyConstructible and Assignable. The standard only requires that fpos
108 : : * should contain a member of type StateT. In this implementation it also
109 : : * contains an offset stored as a signed integer.
110 : : *
111 : : * @param StateT Type passed to and returned from state().
112 : : */
113 : : template<typename _StateT>
114 : : class fpos
115 : : {
116 : : private:
117 : : streamoff _M_off;
118 : : _StateT _M_state;
119 : :
120 : : public:
121 : : // The standard doesn't require that fpos objects can be default
122 : : // constructed. This implementation provides a default
123 : : // constructor that initializes the offset to 0 and default
124 : : // constructs the state.
125 : : fpos()
126 : : : _M_off(0), _M_state() { }
127 : :
128 : : // The standard requires that fpos objects can be constructed
129 : : // from streamoff objects using the constructor syntax, and
130 : : // fails to give any meaningful semantics. In this
131 : : // implementation implicit conversion is also allowed, and this
132 : : // constructor stores the streamoff as the offset and default
133 : : // constructs the state.
134 : : /// Construct position from offset.
135 : 0 : fpos(streamoff __off)
136 : 0 : : _M_off(__off), _M_state() { }
137 : :
138 : : /// Convert to streamoff.
139 : 103458 : operator streamoff() const { return _M_off; }
140 : :
141 : : /// Remember the value of @a st.
142 : : void
143 : : state(_StateT __st)
144 : : { _M_state = __st; }
145 : :
146 : : /// Return the last set value of @a st.
147 : : _StateT
148 : : state() const
149 : : { return _M_state; }
150 : :
151 : : // The standard requires that this operator must be defined, but
152 : : // gives no semantics. In this implementation it just adds its
153 : : // argument to the stored offset and returns *this.
154 : : /// Add offset to this position.
155 : : fpos&
156 : : operator+=(streamoff __off)
157 : : {
158 : : _M_off += __off;
159 : : return *this;
160 : : }
161 : :
162 : : // The standard requires that this operator must be defined, but
163 : : // gives no semantics. In this implementation it just subtracts
164 : : // its argument from the stored offset and returns *this.
165 : : /// Subtract offset from this position.
166 : : fpos&
167 : : operator-=(streamoff __off)
168 : : {
169 : : _M_off -= __off;
170 : : return *this;
171 : : }
172 : :
173 : : // The standard requires that this operator must be defined, but
174 : : // defines its semantics only in terms of operator-. In this
175 : : // implementation it constructs a copy of *this, adds the
176 : : // argument to that copy using operator+= and then returns the
177 : : // copy.
178 : : /// Add position and offset.
179 : : fpos
180 : : operator+(streamoff __off) const
181 : : {
182 : : fpos __pos(*this);
183 : : __pos += __off;
184 : : return __pos;
185 : : }
186 : :
187 : : // The standard requires that this operator must be defined, but
188 : : // defines its semantics only in terms of operator+. In this
189 : : // implementation it constructs a copy of *this, subtracts the
190 : : // argument from that copy using operator-= and then returns the
191 : : // copy.
192 : : /// Subtract offset from position.
193 : : fpos
194 : : operator-(streamoff __off) const
195 : : {
196 : : fpos __pos(*this);
197 : : __pos -= __off;
198 : : return __pos;
199 : : }
200 : :
201 : : // The standard requires that this operator must be defined, but
202 : : // defines its semantics only in terms of operator+. In this
203 : : // implementation it returns the difference between the offset
204 : : // stored in *this and in the argument.
205 : : /// Subtract position to return offset.
206 : : streamoff
207 : : operator-(const fpos& __other) const
208 : : { return _M_off - __other._M_off; }
209 : : };
210 : :
211 : : // The standard only requires that operator== must be an
212 : : // equivalence relation. In this implementation two fpos<StateT>
213 : : // objects belong to the same equivalence class if the contained
214 : : // offsets compare equal.
215 : : /// Test if equivalent to another position.
216 : : template<typename _StateT>
217 : : inline bool
218 : 51729 : operator==(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
219 : 51729 : { return streamoff(__lhs) == streamoff(__rhs); }
220 : :
221 : : template<typename _StateT>
222 : : inline bool
223 : : operator!=(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
224 : : { return streamoff(__lhs) != streamoff(__rhs); }
225 : :
226 : : // Clauses 21.1.3.1 and 21.1.3.2 describe streampos and wstreampos
227 : : // as implementation defined types, but clause 27.2 requires that
228 : : // they must both be typedefs for fpos<mbstate_t>
229 : : /// File position for char streams.
230 : : typedef fpos<mbstate_t> streampos;
231 : : /// File position for wchar_t streams.
232 : : typedef fpos<mbstate_t> wstreampos;
233 : :
234 : : #ifdef __GXX_EXPERIMENTAL_CXX0X__
235 : : /// File position for char16_t streams.
236 : : typedef fpos<mbstate_t> u16streampos;
237 : : /// File position for char32_t streams.
238 : : typedef fpos<mbstate_t> u32streampos;
239 : : #endif
240 : :
241 : : _GLIBCXX_END_NAMESPACE_VERSION
242 : : } // namespace
243 : :
244 : : #endif
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