contrib/gcc-4.4/libstdc++-v3/include/bits/unique_ptr.h

   1 // unique_ptr implementation -*- C++ -*-
   2
   3 // Copyright (C) 2008, 2009 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // Under Section 7 of GPL version 3, you are granted additional
  17 // permissions described in the GCC Runtime Library Exception, version
  18 // 3.1, as published by the Free Software Foundation.
  19
  20 // You should have received a copy of the GNU General Public License and
  21 // a copy of the GCC Runtime Library Exception along with this program;
  22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23 // <http://www.gnu.org/licenses/>.
  24
  25 /** @file unique_ptr.h
  26  *  This is an internal header file, included by other library headers.
  27  *  You should not attempt to use it directly.
  28  */
  29
  30 #ifndef _UNIQUE_PTR_H
  31 #define _UNIQUE_PTR_H 1
  32
  33 #ifndef __GXX_EXPERIMENTAL_CXX0X__
  34 # include <c++0x_warning.h>
  35 #endif
  36
  37 #include <bits/c++config.h>
  38 #include <debug/debug.h>
  39 #include <type_traits>
  40 #include <utility>
  41 #include <tuple>
  42
  43 _GLIBCXX_BEGIN_NAMESPACE(std)
  44
  45   /**
  46    * @addtogroup pointer_abstractions
  47    * @{
  48    */
  49
  50   /// Primary template, default_delete.
  51   template<typename _Tp>
  52     struct default_delete
  53       {
  54         default_delete() { }
  55
  56         template<typename _Up>
  57           default_delete(const default_delete<_Up>&) { }
  58
  59         void
  60         operator()(_Tp* __ptr) const
  61         {
  62           static_assert(sizeof(_Tp)>0,
  63                         "can't delete pointer to incomplete type");
  64           delete __ptr;
  65         }
  66     };
  67
  68   // _GLIBCXX_RESOLVE_LIB_DEFECTS
  69   // DR 740 - omit specialization for array objects with a compile time length
  70   /// Specialization, default_delete.
  71   template<typename _Tp>
  72     struct default_delete<_Tp[]>
  73     {
  74       void
  75       operator()(_Tp* __ptr) const
  76       {
  77         static_assert(sizeof(_Tp)>0,
  78                       "can't delete pointer to incomplete type");
  79         delete [] __ptr;
  80       }
  81     };
  82
  83   /// 20.7.12.2 unique_ptr for single objects.
  84   template <typename _Tp, typename _Tp_Deleter = default_delete<_Tp> >
  85     class unique_ptr
  86     {
  87       typedef std::tuple<_Tp*, _Tp_Deleter>  __tuple_type;
  88       typedef __tuple_type unique_ptr::*     __unspecified_bool_type;
  89       typedef _Tp* unique_ptr::*             __unspecified_pointer_type;
  90
  91     public:
  92       typedef _Tp*               pointer;
  93       typedef _Tp                element_type;
  94       typedef _Tp_Deleter        deleter_type;
  95
  96       // Constructors.
  97       unique_ptr()
  98       : _M_t(pointer(), deleter_type())
  99       { static_assert(!std::is_pointer<deleter_type>::value,
 100                       "constructed with null function pointer deleter"); }
 101
 102       explicit
 103       unique_ptr(pointer __p)
 104       : _M_t(__p, deleter_type())
 105       { static_assert(!std::is_pointer<deleter_type>::value,
 106                      "constructed with null function pointer deleter"); }
 107
 108       unique_ptr(pointer __p,
 109           typename std::conditional<std::is_reference<deleter_type>::value,
 110             deleter_type, const deleter_type&>::type __d)
 111       : _M_t(__p, __d) { }
 112
 113       unique_ptr(pointer __p,
 114           typename std::remove_reference<deleter_type>::type&& __d)
 115       : _M_t(std::move(__p), std::move(__d))
 116       { static_assert(!std::is_reference<deleter_type>::value,
 117                       "rvalue deleter bound to reference"); }
 118
 119       // Move constructors.
 120       unique_ptr(unique_ptr&& __u)
 121       : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }
 122
 123       template<typename _Up, typename _Up_Deleter>
 124         unique_ptr(unique_ptr<_Up, _Up_Deleter>&& __u)
 125         : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter()))
 126         { }
 127
 128       // Destructor.
 129       ~unique_ptr() { reset(); }
 130
 131       // Assignment.
 132       unique_ptr&
 133       operator=(unique_ptr&& __u)
 134       {
 135         reset(__u.release());
 136         get_deleter() = std::move(__u.get_deleter());
 137         return *this;
 138       }
 139
 140       template<typename _Up, typename _Up_Deleter>
 141         unique_ptr&
 142         operator=(unique_ptr<_Up, _Up_Deleter>&& __u)
 143         {
 144           reset(__u.release());
 145           get_deleter() = std::move(__u.get_deleter());
 146           return *this;
 147         }
 148
 149       unique_ptr&
 150       operator=(__unspecified_pointer_type)
 151       {
 152         reset();
 153         return *this;
 154       }
 155
 156       // Observers.
 157       typename std::add_lvalue_reference<element_type>::type operator*() const
 158       {
 159         _GLIBCXX_DEBUG_ASSERT(get() != 0);
 160         return *get();
 161       }
 162
 163       pointer
 164       operator->() const
 165       {
 166         _GLIBCXX_DEBUG_ASSERT(get() != 0);
 167         return get();
 168       }
 169
 170       pointer
 171       get() const
 172       { return std::get<0>(_M_t); }
 173
 174       typename std::add_lvalue_reference<deleter_type>::type
 175       get_deleter()
 176       { return std::get<1>(_M_t); }
 177
 178       typename std::add_lvalue_reference<
 179           typename std::add_const<deleter_type>::type
 180               >::type
 181       get_deleter() const
 182       { return std::get<1>(_M_t); }
 183
 184       operator __unspecified_bool_type () const
 185       { return get() == 0 ? 0 : &unique_ptr::_M_t; }
 186
 187       // Modifiers.
 188       pointer
 189       release()
 190       {
 191         pointer __p = get();
 192         std::get<0>(_M_t) = 0;
 193         return __p;
 194       }
 195
 196       void
 197       reset(pointer __p = pointer())
 198       {
 199         if (__p != get())
 200           {
 201             get_deleter()(get());
 202             std::get<0>(_M_t) = __p;
 203           }
 204       }
 205
 206       void
 207       swap(unique_ptr&& __u)
 208       {
 209         using std::swap;
 210         swap(_M_t, __u._M_t);
 211       }
 212
 213       // Disable copy from lvalue.
 214       unique_ptr(const unique_ptr&) = delete;
 215
 216       template<typename _Up, typename _Up_Deleter>
 217         unique_ptr(const unique_ptr<_Up, _Up_Deleter>&) = delete;
 218
 219       unique_ptr& operator=(const unique_ptr&) = delete;
 220
 221       template<typename _Up, typename _Up_Deleter>
 222         unique_ptr& operator=(const unique_ptr<_Up, _Up_Deleter>&) = delete;
 223
 224     private:
 225       __tuple_type _M_t;
 226   };
 227
 228   /// 20.7.12.3 unique_ptr for array objects with a runtime length
 229   // [unique.ptr.runtime]
 230   // _GLIBCXX_RESOLVE_LIB_DEFECTS
 231   // DR 740 - omit specialization for array objects with a compile time length
 232   template<typename _Tp, typename _Tp_Deleter>
 233     class unique_ptr<_Tp[], _Tp_Deleter>
 234     {
 235       typedef std::tuple<_Tp*, _Tp_Deleter>  __tuple_type;
 236       typedef __tuple_type unique_ptr::*     __unspecified_bool_type;
 237       typedef _Tp* unique_ptr::*             __unspecified_pointer_type;
 238
 239     public:
 240       typedef _Tp*               pointer;
 241       typedef _Tp                element_type;
 242       typedef _Tp_Deleter        deleter_type;
 243
 244       // Constructors.
 245       unique_ptr()
 246       : _M_t(pointer(), deleter_type())
 247       { static_assert(!std::is_pointer<deleter_type>::value,
 248                       "constructed with null function pointer deleter"); }
 249
 250       explicit
 251       unique_ptr(pointer __p)
 252       : _M_t(__p, deleter_type())
 253       { static_assert(!std::is_pointer<deleter_type>::value,
 254                       "constructed with null function pointer deleter"); }
 255
 256       unique_ptr(pointer __p,
 257           typename std::conditional<std::is_reference<deleter_type>::value,
 258               deleter_type, const deleter_type&>::type __d)
 259       : _M_t(__p, __d) { }
 260
 261       unique_ptr(pointer __p,
 262                  typename std::remove_reference<deleter_type>::type && __d)
 263       : _M_t(std::move(__p), std::move(__d))
 264       { static_assert(!std::is_reference<deleter_type>::value,
 265                       "rvalue deleter bound to reference"); }
 266
 267       // Move constructors.
 268       unique_ptr(unique_ptr&& __u)
 269       : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }
 270
 271       template<typename _Up, typename _Up_Deleter>
 272         unique_ptr(unique_ptr<_Up, _Up_Deleter>&& __u)
 273         : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter()))
 274         { }
 275
 276       // Destructor.
 277       ~unique_ptr() { reset(); }
 278
 279       // Assignment.
 280       unique_ptr&
 281       operator=(unique_ptr&& __u)
 282       {
 283         reset(__u.release());
 284         get_deleter() = std::move(__u.get_deleter());
 285         return *this;
 286       }
 287
 288       template<typename _Up, typename _Up_Deleter>
 289         unique_ptr&
 290         operator=(unique_ptr<_Up, _Up_Deleter>&& __u)
 291         {
 292           reset(__u.release());
 293           get_deleter() = std::move(__u.get_deleter());
 294           return *this;
 295         }
 296
 297       unique_ptr&
 298       operator=(__unspecified_pointer_type)
 299       {
 300         reset();
 301         return *this;
 302       }
 303
 304       // Observers.
 305       typename std::add_lvalue_reference<element_type>::type
 306       operator[](size_t __i) const
 307       {
 308         _GLIBCXX_DEBUG_ASSERT(get() != 0);
 309         return get()[__i];
 310       }
 311
 312       pointer
 313       get() const
 314       { return std::get<0>(_M_t); }
 315
 316       typename std::add_lvalue_reference<deleter_type>::type
 317       get_deleter()
 318       { return std::get<1>(_M_t); }
 319
 320       typename std::add_lvalue_reference<
 321           typename std::add_const<deleter_type>::type
 322               >::type
 323       get_deleter() const
 324       { return std::get<1>(_M_t); }
 325
 326       operator __unspecified_bool_type () const
 327       { return get() == 0 ? 0 : &unique_ptr::_M_t; }
 328
 329       // Modifiers.
 330       pointer
 331       release()
 332       {
 333         pointer __p = get();
 334         std::get<0>(_M_t) = 0;
 335         return __p;
 336       }
 337
 338       void
 339       reset(pointer __p = pointer())
 340       {
 341         if (__p != get())
 342         {
 343           get_deleter()(get());
 344           std::get<0>(_M_t) = __p;
 345         }
 346       }
 347
 348       // DR 821.
 349       template<typename _Up>
 350         void reset(_Up) = delete;
 351
 352       void
 353       swap(unique_ptr&& __u)
 354       {
 355         using std::swap;
 356         swap(_M_t, __u._M_t);
 357       }
 358
 359       // Disable copy from lvalue.
 360       unique_ptr(const unique_ptr&) = delete;
 361       unique_ptr& operator=(const unique_ptr&) = delete;
 362
 363       // Disable construction from convertible pointer types.
 364       // (N2315 - 20.6.5.3.1)
 365       template<typename _Up>
 366         unique_ptr(_Up*, typename
 367                    std::conditional<std::is_reference<deleter_type>::value,
 368                    deleter_type, const deleter_type&>::type,
 369                    typename std::enable_if<std::is_convertible<_Up*,
 370                    pointer>::value>::type* = 0) = delete;
 371
 372       template<typename _Up>
 373         unique_ptr(_Up*, typename std::remove_reference<deleter_type>::type&&,
 374                    typename std::enable_if<std::is_convertible<_Up*,
 375                    pointer>::value>::type* = 0) = delete;
 376
 377       template<typename _Up>
 378         explicit
 379         unique_ptr(_Up*, typename std::enable_if<std::is_convertible<_Up*,
 380                    pointer>::value>::type* = 0) = delete;
 381
 382     private:
 383       __tuple_type _M_t;
 384   };
 385
 386   template<typename _Tp, typename _Tp_Deleter>
 387     inline void
 388     swap(unique_ptr<_Tp, _Tp_Deleter>& __x,
 389          unique_ptr<_Tp, _Tp_Deleter>& __y)
 390     { __x.swap(__y); }
 391
 392   template<typename _Tp, typename _Tp_Deleter>
 393     inline void
 394     swap(unique_ptr<_Tp, _Tp_Deleter>&& __x,
 395          unique_ptr<_Tp, _Tp_Deleter>& __y)
 396     { __x.swap(__y); }
 397
 398   template<typename _Tp, typename _Tp_Deleter>
 399     inline void
 400     swap(unique_ptr<_Tp, _Tp_Deleter>& __x,
 401          unique_ptr<_Tp, _Tp_Deleter>&& __y)
 402     { __x.swap(__y); }
 403
 404   template<typename _Tp, typename _Tp_Deleter,
 405            typename _Up, typename _Up_Deleter>
 406     inline bool
 407     operator==(const unique_ptr<_Tp, _Tp_Deleter>& __x,
 408                const unique_ptr<_Up, _Up_Deleter>& __y)
 409     { return __x.get() == __y.get(); }
 410
 411   template<typename _Tp, typename _Tp_Deleter,
 412            typename _Up, typename _Up_Deleter>
 413     inline bool
 414     operator!=(const unique_ptr<_Tp, _Tp_Deleter>& __x,
 415                const unique_ptr<_Up, _Up_Deleter>& __y)
 416     { return !(__x.get() == __y.get()); }
 417
 418   template<typename _Tp, typename _Tp_Deleter,
 419            typename _Up, typename _Up_Deleter>
 420     inline bool
 421     operator<(const unique_ptr<_Tp, _Tp_Deleter>& __x,
 422               const unique_ptr<_Up, _Up_Deleter>& __y)
 423     { return __x.get() < __y.get(); }
 424
 425   template<typename _Tp, typename _Tp_Deleter,
 426            typename _Up, typename _Up_Deleter>
 427     inline bool
 428     operator<=(const unique_ptr<_Tp, _Tp_Deleter>& __x,
 429                const unique_ptr<_Up, _Up_Deleter>& __y)
 430     { return !(__y.get() < __x.get()); }
 431
 432   template<typename _Tp, typename _Tp_Deleter,
 433            typename _Up, typename _Up_Deleter>
 434     inline bool
 435     operator>(const unique_ptr<_Tp, _Tp_Deleter>& __x,
 436               const unique_ptr<_Up, _Up_Deleter>& __y)
 437     { return __y.get() < __x.get(); }
 438
 439   template<typename _Tp, typename _Tp_Deleter,
 440            typename _Up, typename _Up_Deleter>
 441     inline bool
 442     operator>=(const unique_ptr<_Tp, _Tp_Deleter>& __x,
 443                const unique_ptr<_Up, _Up_Deleter>& __y)
 444     { return !(__x.get() < __y.get()); }
 445
 446   // @} group pointer_abstractions
 447
 448 _GLIBCXX_END_NAMESPACE
 449
 450 #endif /* _UNIQUE_PTR_H */