1/*
2 * Copyright (c) 2003
3 * Francois Dumont
4 *
5 * This material is provided "as is", with absolutely no warranty expressed
6 * or implied. Any use is at your own risk.
7 *
8 * Permission to use or copy this software for any purpose is hereby granted
9 * without fee, provided the above notices are retained on all copies.
10 * Permission to modify the code and to distribute modified code is granted,
11 * provided the above notices are retained, and a notice that the code was
12 * modified is included with the above copyright notice.
13 *
14 */
15
16/* NOTE: This is an internal header file, included by other STL headers.
17 *   You should not attempt to use it directly.
18 */
19
20#ifndef _STLP_POINTERS_SPEC_TOOLS_H
21#define _STLP_POINTERS_SPEC_TOOLS_H
22
23#ifndef _STLP_TYPE_TRAITS_H
24#  include <stl/type_traits.h>
25#endif
26
27_STLP_BEGIN_NAMESPACE
28
29//Some usefull declarations:
30template <class _Tp> struct less;
31
32_STLP_MOVE_TO_PRIV_NAMESPACE
33
34template <class _StorageT, class _ValueT, class _BinaryPredicate>
35struct _BinaryPredWrapper;
36
37/*
38 * Since the compiler only allows at most one non-trivial
39 * implicit conversion we can make use of a shim class to
40 * be sure that functions below doesn't accept classes with
41 * implicit pointer conversion operators
42 */
43struct _VoidPointerShim
44{ _VoidPointerShim(void*); };
45struct _ConstVoidPointerShim
46{ _ConstVoidPointerShim(const void*); };
47struct _VolatileVoidPointerShim
48{ _VolatileVoidPointerShim(volatile void*); };
49struct _ConstVolatileVoidPointerShim
50{ _ConstVolatileVoidPointerShim(const volatile void*); };
51
52//The dispatch functions:
53template <class _Tp>
54char _UseVoidPtrStorageType(const __false_type& /*POD*/, const _Tp&);
55char _UseVoidPtrStorageType(const __true_type& /*POD*/, ...);
56char* _UseVoidPtrStorageType(const __true_type& /*POD*/, _VoidPointerShim);
57
58template <class _Tp>
59char _UseConstVoidPtrStorageType(const __false_type& /*POD*/, const _Tp&);
60char _UseConstVoidPtrStorageType(const __true_type& /*POD*/, ...);
61char* _UseConstVoidPtrStorageType(const __true_type& /*POD*/, _ConstVoidPointerShim);
62
63template <class _Tp>
64char _UseVolatileVoidPtrStorageType(const __false_type& /*POD*/, const _Tp&);
65char _UseVolatileVoidPtrStorageType(const __true_type& /*POD*/, ...);
66char* _UseVolatileVoidPtrStorageType(const __true_type& /*POD*/, _VolatileVoidPointerShim);
67
68template <class _Tp>
69char _UseConstVolatileVoidPtrStorageType(const __false_type& /*POD*/, const _Tp&);
70char _UseConstVolatileVoidPtrStorageType(const __true_type& /*POD*/, ...);
71char* _UseConstVolatileVoidPtrStorageType(const __true_type& /*POD*/, _ConstVolatileVoidPointerShim);
72
73#if defined (_STLP_CLASS_PARTIAL_SPECIALIZATION)
74/* Thanks to class partial specialization the pointer specialization feature can even be used in
75 * presence of incomplete type:
76 * struct MyStruct {
77 *   typedef vector<MyStruct> MyStructContainer;
78 *   typedef MyStructContainer::iterator MyStructIterator;
79 * };
80 */
81
82template <class _Tp>
83struct _StorageType {
84  typedef _Tp _QualifiedType;
85  typedef _Tp _Type;
86  enum { use_const_volatile_void_ptr = 0 };
87};
88
89template <class _Tp>
90struct _StorageType<_Tp*> {
91  // Even if we detect a pointer type we use dispatch function to consider if it can be stored as a void*.
92  // For instance function pointer might not necessarily be convertible to void*.
93  enum { use_void_ptr = (sizeof(_STLP_PRIV _UseVoidPtrStorageType(__true_type(),
94                                                                  __STATIC_CAST(_Tp*, 0))) == sizeof(char*))  };
95  enum { use_const_volatile_void_ptr = use_void_ptr };
96  typedef typename __select<use_void_ptr,
97                            void*,
98                            _Tp*>::_Ret _QualifiedType;
99  typedef _QualifiedType _Type;
100};
101
102template <class _Tp>
103struct _StorageType<_Tp const*> {
104  enum { use_void_ptr = (sizeof(_STLP_PRIV _UseConstVoidPtrStorageType(__true_type(),
105                                                                       __STATIC_CAST(const _Tp*, 0))) == sizeof(char*)) };
106  enum { use_const_volatile_void_ptr = use_void_ptr };
107  typedef typename __select<use_void_ptr,
108                            const void*,
109                            const _Tp*>::_Ret _QualifiedType;
110  typedef typename __select<use_void_ptr,
111                            void*,
112                            const _Tp*>::_Ret _Type;
113};
114
115template <class _Tp>
116struct _StorageType<_Tp volatile*> {
117  enum { use_void_ptr = (sizeof(_STLP_PRIV _UseVolatileVoidPtrStorageType(__true_type(),
118                                                                          __STATIC_CAST(_Tp volatile*, 0))) == sizeof(char*)) };
119  enum { use_const_volatile_void_ptr = use_void_ptr };
120  typedef typename __select<use_void_ptr,
121                            volatile void*,
122                            volatile _Tp*>::_Ret _QualifiedType;
123  typedef typename __select<use_void_ptr,
124                            void*,
125                            volatile _Tp*>::_Ret _Type;
126};
127
128template <class _Tp>
129struct _StorageType<_Tp const volatile*> {
130  enum { use_void_ptr = (sizeof(_STLP_PRIV _UseConstVolatileVoidPtrStorageType(__true_type(),
131                                                                               __STATIC_CAST(_Tp const volatile*, 0))) == sizeof(char*)) };
132  enum { use_const_volatile_void_ptr = use_void_ptr };
133  typedef typename __select<use_void_ptr,
134                            const volatile void*,
135                            const volatile _Tp*>::_Ret _QualifiedType;
136  typedef typename __select<use_void_ptr,
137                            void*,
138                            const volatile _Tp*>::_Ret _Type;
139};
140#else
141template <class _Tp>
142struct _StorageType {
143  typedef typename __type_traits<_Tp>::is_POD_type _PODType;
144
145#if !defined (__BORLANDC__) || (__BORLANDC__ != 0x560)
146  static _Tp __null_rep();
147#else
148  static _Tp __null_rep;
149#endif
150  enum { use_void_ptr = (sizeof(_STLP_PRIV _UseVoidPtrStorageType(_PODType(), __null_rep())) == sizeof(char*)) };
151  enum { use_const_void_ptr = (sizeof(_STLP_PRIV _UseConstVoidPtrStorageType(_PODType(), __null_rep())) == sizeof(char*)) };
152  enum { use_volatile_void_ptr = (sizeof(_STLP_PRIV _UseVolatileVoidPtrStorageType(_PODType(), __null_rep())) == sizeof(char*)) };
153  enum { use_const_volatile_void_ptr = (sizeof(_STLP_PRIV _UseConstVolatileVoidPtrStorageType(_PODType(), __null_rep())) == sizeof(char*)) };
154
155  typedef typename __select<!use_const_volatile_void_ptr,
156                            _Tp,
157          typename __select<use_void_ptr,
158                            void*,
159          typename __select<use_const_void_ptr,
160                            const void*,
161          typename __select<use_volatile_void_ptr,
162                            volatile void*,
163                            const volatile void*>::_Ret >::_Ret >::_Ret >::_Ret _QualifiedType;
164
165#if !defined (_STLP_CLASS_PARTIAL_SPECIALIZATION)
166  /* If the compiler do not support the iterator_traits structure we cannot wrap
167   * iterators pass to container template methods. The iterator dereferenced value
168   * has to be storable without any cast in the chosen storage type. To guaranty
169   * that the void pointer has to be correctly qualified.
170   */
171  typedef _QualifiedType _Type;
172#else
173  /* With iterator_traits we can wrap passed iterators and make the necessary casts.
174   * We can always use a simple void* storage type:
175   */
176  typedef typename __select<use_const_volatile_void_ptr,
177                            void*,
178                            _Tp>::_Ret _Type;
179#endif
180};
181#endif
182
183template <class _Tp, class _Compare>
184struct _AssocStorageTypes {
185  typedef _StorageType<_Tp> _StorageTypeInfo;
186  typedef typename _StorageTypeInfo::_Type _SType;
187
188  //We need to also check that the comparison functor used to instanciate the assoc container
189  //is the default Standard less implementation:
190  enum { ptr_type = _StorageTypeInfo::use_const_volatile_void_ptr };
191  typedef typename _IsSTLportClass<_Compare>::_Ret _STLportLess;
192  enum { is_default_less = __type2bool<_STLportLess>::_Ret };
193  typedef typename __select<is_default_less, _SType, _Tp>::_Ret _KeyStorageType;
194  typedef typename __select<is_default_less && ptr_type,
195                            _BinaryPredWrapper<_KeyStorageType, _Tp, _Compare>,
196                            _Compare>::_Ret _CompareStorageType;
197};
198
199
200#if defined (_STLP_CLASS_PARTIAL_SPECIALIZATION)
201/*
202 * Base struct to deal with qualifiers
203 */
204template <class _StorageT, class _QualifiedStorageT>
205struct _VoidCastTraitsAux {
206  typedef _QualifiedStorageT void_cv_type;
207  typedef _StorageT void_type;
208
209  static void_type * uncv_ptr(void_cv_type *__ptr)
210  { return __ptr; }
211  static void_type const* uncv_cptr(void_cv_type const*__ptr)
212  { return __ptr; }
213  static void_type ** uncv_pptr(void_cv_type **__ptr)
214  { return __ptr; }
215  static void_type & uncv_ref(void_cv_type & __ref)
216  { return __ref; }
217  static void_type const& uncv_cref(void_cv_type const& __ref)
218  { return __ref; }
219  static void_cv_type* cv_ptr(void_type *__ptr)
220  { return __ptr; }
221  static void_cv_type const* cv_cptr(void_type const*__ptr)
222  { return __ptr; }
223  static void_cv_type ** cv_pptr(void_type **__ptr)
224  { return __ptr; }
225  static void_cv_type & cv_ref(void_type & __ref)
226  { return __ref; }
227  static void_cv_type const& cv_cref(void_type const& __ref)
228  { return __ref; }
229};
230
231template <class _VoidCVType>
232struct _VoidCastTraitsAuxBase {
233  typedef _VoidCVType* void_cv_type;
234  typedef void* void_type;
235
236  static void_type* uncv_ptr(void_cv_type *__ptr)
237  { return __CONST_CAST(void_type*, __ptr); }
238  static void_type const* uncv_cptr(void_cv_type const*__ptr)
239  { return __CONST_CAST(void_type const*, __ptr); }
240  static void_type** uncv_pptr(void_cv_type **__ptr)
241  { return __CONST_CAST(void_type**, __ptr); }
242  static void_type& uncv_ref(void_cv_type &__ref)
243  { return __CONST_CAST(void_type&, __ref); }
244  static void_type const& uncv_cref(void_cv_type const& __ptr)
245  { return __CONST_CAST(void_type const&, __ptr); }
246  // The reverse versions
247  static void_cv_type * cv_ptr(void_type *__ptr)
248  { return __CONST_CAST(void_cv_type *, __ptr); }
249  static void_cv_type const* cv_cptr(void_type const*__ptr)
250  { return __CONST_CAST(void_cv_type const*, __ptr); }
251  static void_cv_type ** cv_pptr(void_type **__ptr)
252  { return __CONST_CAST(void_cv_type**, __ptr); }
253  static void_cv_type & cv_ref(void_type &__ref)
254  { return __CONST_CAST(void_cv_type &, __ref); }
255  static void_cv_type const& cv_cref(void_type const& __ref)
256  { return __CONST_CAST(void_cv_type const&, __ref); }
257};
258
259_STLP_TEMPLATE_NULL
260struct _VoidCastTraitsAux<void*, const void*> : _VoidCastTraitsAuxBase<void const>
261{};
262_STLP_TEMPLATE_NULL
263struct _VoidCastTraitsAux<void*, volatile void*> : _VoidCastTraitsAuxBase<void volatile>
264{};
265_STLP_TEMPLATE_NULL
266struct _VoidCastTraitsAux<void*, const volatile void*> : _VoidCastTraitsAuxBase<void const volatile>
267{};
268
269template <class _StorageT, class _ValueT>
270struct _CastTraits {
271  typedef _ValueT value_type;
272  typedef typename _StorageType<_ValueT>::_QualifiedType _QualifiedStorageT;
273  typedef _VoidCastTraitsAux<_StorageT, _QualifiedStorageT> cv_traits;
274  typedef typename cv_traits::void_type void_type;
275  typedef typename cv_traits::void_cv_type void_cv_type;
276
277  static value_type * to_value_type_ptr(void_type *__ptr)
278  { return __REINTERPRET_CAST(value_type *, cv_traits::cv_ptr(__ptr)); }
279  static value_type const* to_value_type_cptr(void_type const*__ptr)
280  { return __REINTERPRET_CAST(value_type const*, cv_traits::cv_cptr(__ptr)); }
281  static value_type ** to_value_type_pptr(void_type **__ptr)
282  { return __REINTERPRET_CAST(value_type **, cv_traits::cv_pptr(__ptr)); }
283  static value_type & to_value_type_ref(void_type &__ref)
284  { return __REINTERPRET_CAST(value_type &, cv_traits::cv_ref(__ref)); }
285  static value_type const& to_value_type_cref(void_type const& __ptr)
286  { return __REINTERPRET_CAST(value_type const&, cv_traits::cv_cref(__ptr)); }
287  // Reverse versions
288  static void_type * to_storage_type_ptr(value_type *__ptr)
289  { return cv_traits::uncv_ptr(__REINTERPRET_CAST(void_cv_type *, __ptr)); }
290  static void_type const* to_storage_type_cptr(value_type const*__ptr)
291  { return cv_traits::uncv_cptr(__REINTERPRET_CAST(void_cv_type const*, __ptr)); }
292  static void_type ** to_storage_type_pptr(value_type **__ptr)
293  { return cv_traits::uncv_pptr(__REINTERPRET_CAST(void_cv_type **, __ptr)); }
294  static void_type const& to_storage_type_cref(value_type const& __ref)
295  { return cv_traits::uncv_cref(__REINTERPRET_CAST(void_cv_type const&, __ref)); }
296
297  //Method used to treat set container template method extension
298  static void_type const& to_storage_type_crefT(value_type const& __ref)
299  { return to_storage_type_cref(__ref); }
300};
301
302template <class _Tp>
303struct _CastTraits<_Tp, _Tp> {
304  typedef _Tp storage_type;
305  typedef _Tp value_type;
306
307  static value_type * to_value_type_ptr(storage_type *__ptr)
308  { return __ptr; }
309  static value_type const* to_value_type_cptr(storage_type const*__ptr)
310  { return __ptr; }
311  static value_type ** to_value_type_pptr(storage_type **__ptr)
312  { return __ptr; }
313  static value_type & to_value_type_ref(storage_type &__ref)
314  { return __ref; }
315  static value_type const& to_value_type_cref(storage_type const&__ref)
316  { return __ref; }
317  // Reverse versions
318  static storage_type * to_storage_type_ptr(value_type *__ptr)
319  { return __ptr; }
320  static storage_type const* to_storage_type_cptr(value_type const*__ptr)
321  { return __ptr; }
322  static storage_type ** to_storage_type_pptr(value_type **__ptr)
323  { return __ptr; }
324  static storage_type const& to_storage_type_cref(value_type const& __ref)
325  { return __ref; }
326
327  //Method used to treat set container template method extension
328  template <class _Tp1>
329  static _Tp1 const& to_storage_type_crefT(_Tp1 const& __ref)
330  { return __ref; }
331};
332
333#define _STLP_USE_ITERATOR_WRAPPER
334
335template <class _StorageT, class _ValueT, class _Iterator>
336struct _IteWrapper {
337  typedef _CastTraits<_StorageT, _ValueT> cast_traits;
338  typedef iterator_traits<_Iterator> _IteTraits;
339
340  typedef typename _IteTraits::iterator_category iterator_category;
341  typedef _StorageT value_type;
342  typedef typename _IteTraits::difference_type difference_type;
343  typedef value_type* pointer;
344  typedef value_type const& const_reference;
345  //This wrapper won't be used for input so to avoid surprise
346  //the reference type will be a const reference:
347  typedef const_reference reference;
348
349  typedef _IteWrapper<_StorageT, _ValueT, _Iterator> _Self;
350  typedef _Self _Ite;
351
352  _IteWrapper(_Iterator &__ite) : _M_ite(__ite) {}
353
354  const_reference operator*() const
355  // See http://code.google.com/p/android/issues/detail?id=38630
356  //{ return cast_traits::to_storage_type_cref(*_M_ite); }
357  { return reinterpret_cast<const_reference>(*_M_ite); }
358
359  _Self& operator= (_Self const& __rhs) {
360    _M_ite = __rhs._M_ite;
361    return *this;
362  }
363
364  _Self& operator++() {
365    ++_M_ite;
366    return *this;
367  }
368
369  _Self& operator--() {
370    --_M_ite;
371    return *this;
372  }
373
374  _Self& operator += (difference_type __offset) {
375    _M_ite += __offset;
376    return *this;
377  }
378  difference_type operator -(_Self const& __other) const
379  { return _M_ite - __other._M_ite; }
380
381  bool operator == (_Self const& __other) const
382  { return _M_ite == __other._M_ite; }
383
384  bool operator != (_Self const& __other) const
385  { return _M_ite != __other._M_ite; }
386
387  bool operator < (_Self const& __rhs) const
388  { return _M_ite < __rhs._M_ite; }
389
390private:
391  _Iterator _M_ite;
392};
393
394template <class _Tp, class _Iterator>
395struct _IteWrapper<_Tp, _Tp, _Iterator>
396{ typedef _Iterator _Ite; };
397
398#else
399
400/*
401 * In this config the storage type is qualified in respect of the
402 * value_type qualification. Simple reinterpret_cast is enough.
403 */
404template <class _StorageT, class _ValueT>
405struct _CastTraits {
406  typedef _StorageT storage_type;
407  typedef _ValueT value_type;
408
409  static value_type * to_value_type_ptr(storage_type *__ptr)
410  { return __REINTERPRET_CAST(value_type*, __ptr); }
411  static value_type const* to_value_type_cptr(storage_type const*__ptr)
412  { return __REINTERPRET_CAST(value_type const*, __ptr); }
413  static value_type ** to_value_type_pptr(storage_type **__ptr)
414  { return __REINTERPRET_CAST(value_type **, __ptr); }
415  static value_type & to_value_type_ref(storage_type &__ref)
416  { return __REINTERPRET_CAST(value_type&, __ref); }
417  static value_type const& to_value_type_cref(storage_type const&__ref)
418  { return __REINTERPRET_CAST(value_type const&, __ref); }
419  // Reverse versions
420  static storage_type * to_storage_type_ptr(value_type *__ptr)
421  { return __REINTERPRET_CAST(storage_type*, __ptr); }
422  static storage_type const* to_storage_type_cptr(value_type const*__ptr)
423  { return __REINTERPRET_CAST(storage_type const*, __ptr); }
424  static storage_type ** to_storage_type_pptr(value_type **__ptr)
425  { return __REINTERPRET_CAST(storage_type **, __ptr); }
426  static storage_type const& to_storage_type_cref(value_type const&__ref)
427  { return __REINTERPRET_CAST(storage_type const&, __ref); }
428  template <class _Tp1>
429  static _Tp1 const& to_storage_type_crefT(_Tp1 const& __ref)
430  { return __ref; }
431};
432
433#endif
434
435//Wrapper functors:
436template <class _StorageT, class _ValueT, class _UnaryPredicate>
437struct _UnaryPredWrapper {
438  typedef _CastTraits<_StorageT, _ValueT> cast_traits;
439
440  _UnaryPredWrapper (_UnaryPredicate const& __pred) : _M_pred(__pred) {}
441
442  bool operator () (_StorageT const& __ref) const
443  { return _M_pred(cast_traits::to_value_type_cref(__ref)); }
444
445private:
446  _UnaryPredicate _M_pred;
447};
448
449template <class _StorageT, class _ValueT, class _BinaryPredicate>
450struct _BinaryPredWrapper {
451  typedef _CastTraits<_StorageT, _ValueT> cast_traits;
452
453  _BinaryPredWrapper () {}
454  _BinaryPredWrapper (_BinaryPredicate const& __pred) : _M_pred(__pred) {}
455
456  _BinaryPredicate get_pred() const { return _M_pred; }
457
458  bool operator () (_StorageT const& __fst, _StorageT const& __snd) const
459  { return _M_pred(cast_traits::to_value_type_cref(__fst), cast_traits::to_value_type_cref(__snd)); }
460
461  //Cast operator used to transparently access underlying predicate
462  //in set::key_comp() method
463  operator _BinaryPredicate() const
464  { return _M_pred; }
465
466private:
467  _BinaryPredicate _M_pred;
468};
469
470_STLP_MOVE_TO_STD_NAMESPACE
471
472_STLP_END_NAMESPACE
473
474#endif /* _STLP_POINTERS_SPEC_TOOLS_H */
475