xref: /reactos/sdk/include/c++/stlport/stl/_tempbuf.h (revision 40462c92)
1 /*
2  *
3  * Copyright (c) 1994
4  * Hewlett-Packard Company
5  *
6  * Copyright (c) 1996,1997
7  * Silicon Graphics Computer Systems, Inc.
8  *
9  * Copyright (c) 1997
10  * Moscow Center for SPARC Technology
11  *
12  * Copyright (c) 1999
13  * Boris Fomitchev
14  *
15  * This material is provided "as is", with absolutely no warranty expressed
16  * or implied. Any use is at your own risk.
17  *
18  * Permission to use or copy this software for any purpose is hereby granted
19  * without fee, provided the above notices are retained on all copies.
20  * Permission to modify the code and to distribute modified code is granted,
21  * provided the above notices are retained, and a notice that the code was
22  * modified is included with the above copyright notice.
23  *
24  */
25 
26 /* NOTE: This is an internal header file, included by other STL headers.
27  *   You should not attempt to use it directly.
28  */
29 
30 #ifndef _STLP_INTERNAL_TEMPBUF_H
31 #define _STLP_INTERNAL_TEMPBUF_H
32 
33 #ifndef _STLP_CLIMITS
34 #  include <climits>
35 #endif
36 
37 #ifndef _STLP_INTERNAL_CSTDLIB
38 #  include <stl/_cstdlib.h>
39 #endif
40 
41 #ifndef _STLP_INTERNAL_UNINITIALIZED_H
42 #  include <stl/_uninitialized.h>
43 #endif
44 
45 _STLP_BEGIN_NAMESPACE
46 
47 template <class _Tp>
48 pair<_Tp*, ptrdiff_t>  _STLP_CALL
49 __get_temporary_buffer(ptrdiff_t __len, _Tp*);
50 
51 #ifndef _STLP_NO_EXPLICIT_FUNCTION_TMPL_ARGS
52 
53 template <class _Tp>
54 inline pair<_Tp*, ptrdiff_t>  _STLP_CALL get_temporary_buffer(ptrdiff_t __len) {
55   return __get_temporary_buffer(__len, (_Tp*) 0);
56 }
57 
58 # if ! defined(_STLP_NO_EXTENSIONS)
59 // This overload is not required by the standard; it is an extension.
60 // It is supported for backward compatibility with the HP STL, and
61 // because not all compilers support the language feature (explicit
62 // function template arguments) that is required for the standard
63 // version of get_temporary_buffer.
64 template <class _Tp>
65 inline pair<_Tp*, ptrdiff_t>  _STLP_CALL
66 get_temporary_buffer(ptrdiff_t __len, _Tp*) {
67   return __get_temporary_buffer(__len, (_Tp*) 0);
68 }
69 # endif
70 #endif
71 
72 template <class _Tp>
73 inline void  _STLP_CALL return_temporary_buffer(_Tp* __p) {
74 // SunPro brain damage
75   free((char*)__p);
76 }
77 
78 template <class _ForwardIterator, class _Tp>
79 class _Temporary_buffer {
80 private:
81   ptrdiff_t  _M_original_len;
82   ptrdiff_t  _M_len;
83   _Tp*       _M_buffer;
84 
85   void _M_allocate_buffer() {
86     _M_original_len = _M_len;
87     _M_buffer = 0;
88 
89     if (_M_len > (ptrdiff_t)(INT_MAX / sizeof(_Tp)))
90       _M_len = INT_MAX / sizeof(_Tp);
91 
92     while (_M_len > 0) {
93       _M_buffer = (_Tp*) malloc(_M_len * sizeof(_Tp));
94       if (_M_buffer)
95         break;
96       _M_len /= 2;
97     }
98   }
99 
100   void _M_initialize_buffer(const _Tp&, const __true_type&) {}
101   void _M_initialize_buffer(const _Tp& val, const __false_type&) {
102     uninitialized_fill_n(_M_buffer, _M_len, val);
103   }
104 
105 public:
106   ptrdiff_t size() const { return _M_len; }
107   ptrdiff_t requested_size() const { return _M_original_len; }
108   _Tp* begin() { return _M_buffer; }
109   _Tp* end() { return _M_buffer + _M_len; }
110 
111   _Temporary_buffer(_ForwardIterator __first, _ForwardIterator __last) {
112     // Workaround for a __type_traits bug in the pre-7.3 compiler.
113 #   if defined(__sgi) && !defined(__GNUC__) && _COMPILER_VERSION < 730
114     typedef typename __type_traits<_Tp>::is_POD_type _Trivial;
115 #   else
116     typedef typename __type_traits<_Tp>::has_trivial_default_constructor  _Trivial;
117 #   endif
118     _STLP_TRY {
119       _M_len = _STLP_STD::distance(__first, __last);
120       _M_allocate_buffer();
121       if (_M_len > 0)
122         _M_initialize_buffer(*__first, _Trivial());
123     }
124     _STLP_UNWIND(free(_M_buffer); _M_buffer = 0; _M_len = 0)
125   }
126 
127   ~_Temporary_buffer() {
128     _STLP_STD::_Destroy_Range(_M_buffer, _M_buffer + _M_len);
129     free(_M_buffer);
130   }
131 
132 private:
133   // Disable copy constructor and assignment operator.
134   _Temporary_buffer(const _Temporary_buffer<_ForwardIterator, _Tp>&) {}
135   void operator=(const _Temporary_buffer<_ForwardIterator, _Tp>&) {}
136 };
137 
138 # ifndef _STLP_NO_EXTENSIONS
139 
140 // Class temporary_buffer is not part of the standard.  It is an extension.
141 
142 template <class _ForwardIterator,
143           class _Tp
144 #ifdef _STLP_CLASS_PARTIAL_SPECIALIZATION
145                     = typename iterator_traits<_ForwardIterator>::value_type
146 #endif /* _STLP_CLASS_PARTIAL_SPECIALIZATION */
147          >
148 struct temporary_buffer : public _Temporary_buffer<_ForwardIterator, _Tp>
149 {
150   temporary_buffer(_ForwardIterator __first, _ForwardIterator __last)
151     : _Temporary_buffer<_ForwardIterator, _Tp>(__first, __last) {}
152   ~temporary_buffer() {}
153 };
154 
155 # endif /* _STLP_NO_EXTENSIONS */
156 
157 _STLP_END_NAMESPACE
158 
159 # ifndef _STLP_LINK_TIME_INSTANTIATION
160 #  include <stl/_tempbuf.c>
161 # endif
162 
163 #endif /* _STLP_INTERNAL_TEMPBUF_H */
164 
165 // Local Variables:
166 // mode:C++
167 // End:
168