libstdc++-v3/libsupc++/cxxabi-internal.h

   1 // new abi support -*- C++ -*-
   2
   3 // Copyright (C) 2000, 2002, 2003, 2004, 2006 Free Software Foundation, Inc.
   4 //
   5 // This file is part of GCC.
   6 //
   7 // GCC is free software; you can redistribute it and/or modify
   8 // it under the terms of the GNU General Public License as published by
   9 // the Free Software Foundation; either version 2, or (at your option)
  10 // any later version.
  11 //
  12 // GCC is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16 //
  17 // You should have received a copy of the GNU General Public License
  18 // along with GCC; see the file COPYING.  If not, write to
  19 // the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  20 // Boston, MA 02110-1301, USA.
  21
  22 // As a special exception, you may use this file as part of a free software
  23 // library without restriction.  Specifically, if other files instantiate
  24 // templates or use macros or inline functions from this file, or you compile
  25 // this file and link it with other files to produce an executable, this
  26 // file does not by itself cause the resulting executable to be covered by
  27 // the GNU General Public License.  This exception does not however
  28 // invalidate any other reasons why the executable file might be covered by
  29 // the GNU General Public License.
  30
  31 // Written by Nathan Sidwell, Codesourcery LLC, <nathan@codesourcery.com>
  32
  33 /* This file declares the new abi entry points into the runtime. It is not
  34    normally necessary for user programs to include this header, or use the
  35    entry points directly. However, this header is available should that be
  36    needed.
  37
  38    Some of the entry points are intended for both C and C++, thus this header
  39    is includable from both C and C++. Though the C++ specific parts are not
  40    available in C, naturally enough.  */
  41
  42 /** @file cxxabi.h
  43  *  The header provides an interface to the C++ ABI.
  44  */
  45
  46 #ifndef _CXXABI_INTERNAL_H
  47 #define _CXXABI_INTERNAL_H 1
  48
  49 #pragma GCC visibility push(default)
  50
  51 #include <stddef.h>
  52 #include <bits/cxxabi_tweaks.h>
  53
  54 #ifdef __cplusplus
  55 namespace __cxxabiv1
  56 {
  57   extern "C"
  58   {
  59 #endif
  60
  61   typedef __cxa_cdtor_return_type (*__cxa_cdtor_type)(void *);
  62
  63   // Allocate array.
  64   void*
  65   __cxa_vec_new(size_t __element_count, size_t __element_size,
  66                 size_t __padding_size, __cxa_cdtor_type constructor,
  67                 __cxa_cdtor_type destructor);
  68
  69   void*
  70   __cxa_vec_new2(size_t __element_count, size_t __element_size,
  71                  size_t __padding_size, __cxa_cdtor_type constructor,
  72                  __cxa_cdtor_type destructor, void *(*__alloc) (size_t),
  73                  void (*__dealloc) (void*));
  74
  75   void*
  76   __cxa_vec_new3(size_t __element_count, size_t __element_size,
  77                  size_t __padding_size, __cxa_cdtor_type constructor,
  78                  __cxa_cdtor_type destructor, void *(*__alloc) (size_t),
  79                  void (*__dealloc) (void*, size_t));
  80
  81   // Construct array.
  82   __cxa_vec_ctor_return_type
  83   __cxa_vec_ctor(void* __array_address, size_t __element_count,
  84                  size_t __element_size, __cxa_cdtor_type constructor,
  85                  __cxa_cdtor_type destructor);
  86
  87   __cxa_vec_ctor_return_type
  88   __cxa_vec_cctor(void* dest_array, void* src_array, size_t element_count,
  89                   size_t element_size,
  90                   __cxa_cdtor_return_type (*constructor) (void*, void*),
  91                   __cxa_cdtor_type destructor);
  92
  93   // Destruct array.
  94   void
  95   __cxa_vec_dtor(void* __array_address, size_t __element_count,
  96                  size_t __element_size, __cxa_cdtor_type destructor);
  97
  98   void
  99   __cxa_vec_cleanup(void* __array_address, size_t __element_count,
 100                     size_t __element_size, __cxa_cdtor_type destructor);
 101
 102   // Destruct and release array.
 103   void
 104   __cxa_vec_delete(void* __array_address, size_t __element_size,
 105                    size_t __padding_size, __cxa_cdtor_type destructor);
 106
 107   void
 108   __cxa_vec_delete2(void* __array_address, size_t __element_size,
 109                     size_t __padding_size, __cxa_cdtor_type destructor,
 110                     void (*__dealloc) (void*));
 111
 112   void
 113   __cxa_vec_delete3(void* __array_address, size_t __element_size,
 114                     size_t __padding_size, __cxa_cdtor_type destructor,
 115                     void (*__dealloc) (void*, size_t));
 116
 117   int
 118   __cxa_guard_acquire(__guard*);
 119
 120   void
 121   __cxa_guard_release(__guard*);
 122
 123   void
 124   __cxa_guard_abort(__guard*);
 125
 126   // Pure virtual functions.
 127   void
 128   __cxa_pure_virtual(void);
 129
 130   // Exception handling.
 131   void
 132   __cxa_bad_cast();
 133
 134   void
 135   __cxa_bad_typeid();
 136
 137   // DSO destruction.
 138   int
 139   __cxa_atexit(void (*)(void*), void*, void*)
 140 #ifdef __cplusplus
 141     throw ()
 142 #endif
 143     ;
 144
 145   int
 146   __cxa_finalize(void*);
 147
 148   // Demangling routines.
 149   char*
 150   __cxa_demangle(const char* __mangled_name, char* __output_buffer,
 151                  size_t* __length, int* __status);
 152 #ifdef __cplusplus
 153   }
 154 } // namespace __cxxabiv1
 155 #endif
 156
 157 #ifdef __cplusplus
 158
 159 #include <typeinfo>
 160
 161 namespace __cxxabiv1
 162 {
 163   // Type information for int, float etc.
 164   class __fundamental_type_info : public std::type_info
 165   {
 166   public:
 167     explicit
 168     __fundamental_type_info(const char* __n) : std::type_info(__n) { }
 169
 170     virtual
 171     ~__fundamental_type_info();
 172   };
 173
 174   // Type information for array objects.
 175   class __array_type_info : public std::type_info
 176   {
 177   public:
 178     explicit
 179     __array_type_info(const char* __n) : std::type_info(__n) { }
 180
 181     virtual
 182     ~__array_type_info();
 183   };
 184
 185   // Type information for functions (both member and non-member).
 186   class __function_type_info : public std::type_info
 187   {
 188   public:
 189     explicit
 190     __function_type_info(const char* __n) : std::type_info(__n) { }
 191
 192     virtual
 193     ~__function_type_info();
 194
 195   protected:
 196     // Implementation defined member function.
 197     virtual bool
 198     __is_function_p() const;
 199   };
 200
 201   // Type information for enumerations.
 202   class __enum_type_info : public std::type_info
 203   {
 204   public:
 205     explicit
 206     __enum_type_info(const char* __n) : std::type_info(__n) { }
 207
 208     virtual
 209     ~__enum_type_info();
 210   };
 211
 212   // Common type information for simple pointers and pointers to member.
 213   class __pbase_type_info : public std::type_info
 214   {
 215   public:
 216     unsigned int                __flags; // Qualification of the target object.
 217     const std::type_info*       __pointee; // Type of pointed to object.
 218
 219     explicit
 220     __pbase_type_info(const char* __n, int __quals,
 221                       const std::type_info* __type)
 222     : std::type_info(__n), __flags(__quals), __pointee(__type)
 223     { }
 224
 225     virtual
 226     ~__pbase_type_info();
 227
 228     // Implementation defined type.
 229     enum __masks
 230       {
 231         __const_mask = 0x1,
 232         __volatile_mask = 0x2,
 233         __restrict_mask = 0x4,
 234         __incomplete_mask = 0x8,
 235         __incomplete_class_mask = 0x10
 236       };
 237
 238   protected:
 239     __pbase_type_info(const __pbase_type_info&);
 240
 241     __pbase_type_info&
 242     operator=(const __pbase_type_info&);
 243
 244     // Implementation defined member functions.
 245     virtual bool
 246     __do_catch(const std::type_info* __thr_type, void** __thr_obj,
 247                unsigned int __outer) const;
 248
 249     inline virtual bool
 250     __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj,
 251                     unsigned __outer) const;
 252   };
 253
 254   // Type information for simple pointers.
 255   class __pointer_type_info : public __pbase_type_info
 256   {
 257   public:
 258     explicit
 259     __pointer_type_info(const char* __n, int __quals,
 260                         const std::type_info* __type)
 261     : __pbase_type_info (__n, __quals, __type) { }
 262
 263
 264     virtual
 265     ~__pointer_type_info();
 266
 267   protected:
 268     // Implementation defined member functions.
 269     virtual bool
 270     __is_pointer_p() const;
 271
 272     virtual bool
 273     __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj,
 274                     unsigned __outer) const;
 275   };
 276
 277   class __class_type_info;
 278
 279   // Type information for a pointer to member variable.
 280   class __pointer_to_member_type_info : public __pbase_type_info
 281   {
 282   public:
 283     __class_type_info* __context;   // Class of the member.
 284
 285     explicit
 286     __pointer_to_member_type_info(const char* __n, int __quals,
 287                                   const std::type_info* __type,
 288                                   __class_type_info* __klass)
 289     : __pbase_type_info(__n, __quals, __type), __context(__klass) { }
 290
 291     virtual
 292     ~__pointer_to_member_type_info();
 293
 294   protected:
 295     __pointer_to_member_type_info(const __pointer_to_member_type_info&);
 296
 297     __pointer_to_member_type_info&
 298     operator=(const __pointer_to_member_type_info&);
 299
 300     // Implementation defined member function.
 301     virtual bool
 302     __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj,
 303                     unsigned __outer) const;
 304   };
 305
 306   // Helper class for __vmi_class_type.
 307   class __base_class_type_info
 308   {
 309   public:
 310     const __class_type_info*    __base_type;  // Base class type.
 311     long                        __offset_flags;  // Offset and info.
 312
 313     enum __offset_flags_masks
 314       {
 315         __virtual_mask = 0x1,
 316         __public_mask = 0x2,
 317         __hwm_bit = 2,
 318         __offset_shift = 8          // Bits to shift offset.
 319       };
 320
 321     // Implementation defined member functions.
 322     bool
 323     __is_virtual_p() const
 324     { return __offset_flags & __virtual_mask; }
 325
 326     bool
 327     __is_public_p() const
 328     { return __offset_flags & __public_mask; }
 329
 330     ptrdiff_t
 331     __offset() const
 332     {
 333       // This shift, being of a signed type, is implementation
 334       // defined. GCC implements such shifts as arithmetic, which is
 335       // what we want.
 336       return static_cast<ptrdiff_t>(__offset_flags) >> __offset_shift;
 337     }
 338   };
 339
 340   // Type information for a class.
 341   class __class_type_info : public std::type_info
 342   {
 343   public:
 344     explicit
 345     __class_type_info (const char *__n) : type_info(__n) { }
 346
 347     virtual
 348     ~__class_type_info ();
 349
 350     // Implementation defined types.
 351     // The type sub_kind tells us about how a base object is contained
 352     // within a derived object. We often do this lazily, hence the
 353     // UNKNOWN value. At other times we may use NOT_CONTAINED to mean
 354     // not publicly contained.
 355     enum __sub_kind
 356       {
 357         // We have no idea.
 358         __unknown = 0,
 359
 360         // Not contained within us (in some circumstances this might
 361         // mean not contained publicly)
 362         __not_contained,
 363
 364         // Contained ambiguously.
 365         __contained_ambig,
 366
 367         // Via a virtual path.
 368         __contained_virtual_mask = __base_class_type_info::__virtual_mask,
 369
 370         // Via a public path.
 371         __contained_public_mask = __base_class_type_info::__public_mask,
 372
 373         // Contained within us.
 374         __contained_mask = 1 << __base_class_type_info::__hwm_bit,
 375
 376         __contained_private = __contained_mask,
 377         __contained_public = __contained_mask | __contained_public_mask
 378       };
 379
 380     struct __upcast_result;
 381     struct __dyncast_result;
 382
 383   protected:
 384     // Implementation defined member functions.
 385     virtual bool
 386     __do_upcast(const __class_type_info* __dst_type, void**__obj_ptr) const;
 387
 388     virtual bool
 389     __do_catch(const type_info* __thr_type, void** __thr_obj,
 390                unsigned __outer) const;
 391
 392   public:
 393     // Helper for upcast. See if DST is us, or one of our bases.
 394     // Return false if not found, true if found.
 395     virtual bool
 396     __do_upcast(const __class_type_info* __dst, const void* __obj,
 397                 __upcast_result& __restrict __result) const;
 398
 399     // Indicate whether SRC_PTR of type SRC_TYPE is contained publicly
 400     // within OBJ_PTR. OBJ_PTR points to a base object of our type,
 401     // which is the destination type. SRC2DST indicates how SRC
 402     // objects might be contained within this type.  If SRC_PTR is one
 403     // of our SRC_TYPE bases, indicate the virtuality. Returns
 404     // not_contained for non containment or private containment.
 405     inline __sub_kind
 406     __find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
 407                       const __class_type_info* __src_type,
 408                       const void* __src_ptr) const;
 409
 410     // Helper for dynamic cast. ACCESS_PATH gives the access from the
 411     // most derived object to this base. DST_TYPE indicates the
 412     // desired type we want. OBJ_PTR points to a base of our type
 413     // within the complete object. SRC_TYPE indicates the static type
 414     // started from and SRC_PTR points to that base within the most
 415     // derived object. Fill in RESULT with what we find. Return true
 416     // if we have located an ambiguous match.
 417     virtual bool
 418     __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path,
 419                  const __class_type_info* __dst_type, const void* __obj_ptr,
 420                  const __class_type_info* __src_type, const void* __src_ptr,
 421                  __dyncast_result& __result) const;
 422
 423     // Helper for find_public_subobj. SRC2DST indicates how SRC_TYPE
 424     // bases are inherited by the type started from -- which is not
 425     // necessarily the current type. The current type will be a base
 426     // of the destination type.  OBJ_PTR points to the current base.
 427     virtual __sub_kind
 428     __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
 429                          const __class_type_info* __src_type,
 430                          const void* __src_ptr) const;
 431   };
 432
 433   // Type information for a class with a single non-virtual base.
 434   class __si_class_type_info : public __class_type_info
 435   {
 436   public:
 437     const __class_type_info* __base_type;
 438
 439     explicit
 440     __si_class_type_info(const char *__n, const __class_type_info *__base)
 441     : __class_type_info(__n), __base_type(__base) { }
 442
 443     virtual
 444     ~__si_class_type_info();
 445
 446   protected:
 447     __si_class_type_info(const __si_class_type_info&);
 448
 449     __si_class_type_info&
 450     operator=(const __si_class_type_info&);
 451
 452     // Implementation defined member functions.
 453     virtual bool
 454     __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path,
 455                  const __class_type_info* __dst_type, const void* __obj_ptr,
 456                  const __class_type_info* __src_type, const void* __src_ptr,
 457                  __dyncast_result& __result) const;
 458
 459     virtual __sub_kind
 460     __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
 461                          const __class_type_info* __src_type,
 462                          const void* __sub_ptr) const;
 463
 464     virtual bool
 465     __do_upcast(const __class_type_info*__dst, const void*__obj,
 466                 __upcast_result& __restrict __result) const;
 467   };
 468
 469   // Type information for a class with multiple and/or virtual bases.
 470   class __vmi_class_type_info : public __class_type_info
 471   {
 472   public:
 473     unsigned int                __flags;  // Details about the class hierarchy.
 474     unsigned int                __base_count;  // Number of direct bases.
 475
 476     // The array of bases uses the trailing array struct hack so this
 477     // class is not constructable with a normal constructor. It is
 478     // internally generated by the compiler.
 479     __base_class_type_info      __base_info[1];  // Array of bases.
 480
 481     explicit
 482     __vmi_class_type_info(const char* __n, int ___flags)
 483     : __class_type_info(__n), __flags(___flags), __base_count(0) { }
 484
 485     virtual
 486     ~__vmi_class_type_info();
 487
 488     // Implementation defined types.
 489     enum __flags_masks
 490       {
 491         __non_diamond_repeat_mask = 0x1, // Distinct instance of repeated base.
 492         __diamond_shaped_mask = 0x2, // Diamond shaped multiple inheritance.
 493         __flags_unknown_mask = 0x10
 494       };
 495
 496   protected:
 497     // Implementation defined member functions.
 498     virtual bool
 499     __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path,
 500                  const __class_type_info* __dst_type, const void* __obj_ptr,
 501                  const __class_type_info* __src_type, const void* __src_ptr,
 502                  __dyncast_result& __result) const;
 503
 504     virtual __sub_kind
 505     __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
 506                          const __class_type_info* __src_type,
 507                          const void* __src_ptr) const;
 508
 509     virtual bool
 510     __do_upcast(const __class_type_info* __dst, const void* __obj,
 511                 __upcast_result& __restrict __result) const;
 512   };
 513
 514   // Dynamic cast runtime.
 515   // src2dst has the following possible values
 516   //  >-1: src_type is a unique public non-virtual base of dst_type
 517   //       dst_ptr + src2dst == src_ptr
 518   //   -1: unspecified relationship
 519   //   -2: src_type is not a public base of dst_type
 520   //   -3: src_type is a multiple public non-virtual base of dst_type
 521   extern "C" void*
 522   __dynamic_cast(const void* __src_ptr, // Starting object.
 523                  const __class_type_info* __src_type, // Static type of object.
 524                  const __class_type_info* __dst_type, // Desired target type.
 525                  ptrdiff_t __src2dst); // How src and dst are related.
 526
 527
 528   // Returns the type_info for the currently handled exception [15.3/8], or
 529   // null if there is none.
 530   extern "C" std::type_info*
 531   __cxa_current_exception_type();
 532
 533   // A magic placeholder class that can be caught by reference
 534   // to recognize forced unwinding.
 535   class __forced_unwind
 536   {
 537     virtual ~__forced_unwind() throw();
 538     virtual void __pure() = 0; // prevent catch by value
 539   };
 540
 541   // A magic placeholder class that can be caught by reference
 542   // to recognize foreign exceptions.
 543   class __foreign_exception
 544   {
 545     virtual ~__foreign_exception() throw();
 546     virtual void __pure() = 0; // prevent catch by value
 547   };
 548
 549 } // namespace __cxxabiv1
 550
 551 #endif // __cplusplus
 552
 553 #pragma GCC visibility pop
 554
 555 #endif // __CXXABI_INTERNAL_H