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

   1 // new abi support -*- C++ -*-
   2
   3 // Copyright (C) 2000, 2002, 2003, 2004, 2006, 2007 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_H
  47 #define _CXXABI_H 1
  48
  49 #pragma GCC visibility push(default)
  50
  51 #include <stddef.h>
  52 #include <bits/cxxabi_tweaks.h>
  53 #include <cxxabi-forced.h>
  54
  55 #ifdef __cplusplus
  56 #define _GLIBCXX_NOTHROW throw()
  57 #else
  58 #define _GLIBCXX_NOTHROW __attribute__((nothrow))
  59 #endif
  60
  61 #ifdef __cplusplus
  62 namespace __cxxabiv1
  63 {
  64   extern "C"
  65   {
  66 #endif
  67
  68   typedef __cxa_cdtor_return_type (*__cxa_cdtor_type)(void *);
  69
  70   // Allocate array.
  71   void*
  72   __cxa_vec_new(size_t __element_count, size_t __element_size,
  73                 size_t __padding_size, __cxa_cdtor_type constructor,
  74                 __cxa_cdtor_type destructor);
  75
  76   void*
  77   __cxa_vec_new2(size_t __element_count, size_t __element_size,
  78                  size_t __padding_size, __cxa_cdtor_type constructor,
  79                  __cxa_cdtor_type destructor, void *(*__alloc) (size_t),
  80                  void (*__dealloc) (void*));
  81
  82   void*
  83   __cxa_vec_new3(size_t __element_count, size_t __element_size,
  84                  size_t __padding_size, __cxa_cdtor_type constructor,
  85                  __cxa_cdtor_type destructor, void *(*__alloc) (size_t),
  86                  void (*__dealloc) (void*, size_t));
  87
  88   // Construct array.
  89   __cxa_vec_ctor_return_type
  90   __cxa_vec_ctor(void* __array_address, size_t __element_count,
  91                  size_t __element_size, __cxa_cdtor_type constructor,
  92                  __cxa_cdtor_type destructor);
  93
  94   __cxa_vec_ctor_return_type
  95   __cxa_vec_cctor(void* dest_array, void* src_array, size_t element_count,
  96                   size_t element_size,
  97                   __cxa_cdtor_return_type (*constructor) (void*, void*),
  98                   __cxa_cdtor_type destructor);
  99
 100   // Destruct array.
 101   void
 102   __cxa_vec_dtor(void* __array_address, size_t __element_count,
 103                  size_t __element_size, __cxa_cdtor_type destructor);
 104
 105   void
 106   __cxa_vec_cleanup(void* __array_address, size_t __element_count,
 107                     size_t __element_size, __cxa_cdtor_type destructor);
 108
 109   // Destruct and release array.
 110   void
 111   __cxa_vec_delete(void* __array_address, size_t __element_size,
 112                    size_t __padding_size, __cxa_cdtor_type destructor);
 113
 114   void
 115   __cxa_vec_delete2(void* __array_address, size_t __element_size,
 116                     size_t __padding_size, __cxa_cdtor_type destructor,
 117                     void (*__dealloc) (void*));
 118
 119   void
 120   __cxa_vec_delete3(void* __array_address, size_t __element_size,
 121                     size_t __padding_size, __cxa_cdtor_type destructor,
 122                     void (*__dealloc) (void*, size_t));
 123
 124   int
 125   __cxa_guard_acquire(__guard*);
 126
 127   void
 128   __cxa_guard_release(__guard*);
 129
 130   void
 131   __cxa_guard_abort(__guard*);
 132
 133   // Pure virtual functions.
 134   void
 135   __cxa_pure_virtual(void);
 136
 137   // Exception handling.
 138   void
 139   __cxa_bad_cast();
 140
 141   void
 142   __cxa_bad_typeid();
 143
 144   // DSO destruction.
 145   int
 146   __cxa_atexit(void (*)(void*), void*, void*) _GLIBCXX_NOTHROW;
 147
 148   int
 149   __cxa_finalize(void*);
 150
 151   // Demangling routines.
 152   char*
 153   __cxa_demangle(const char* __mangled_name, char* __output_buffer,
 154                  size_t* __length, int* __status);
 155 #ifdef __cplusplus
 156   }
 157 } // namespace __cxxabiv1
 158 #endif
 159
 160 #ifdef __cplusplus
 161
 162 #include <typeinfo>
 163
 164 namespace __cxxabiv1
 165 {
 166   // Type information for int, float etc.
 167   class __fundamental_type_info : public std::type_info
 168   {
 169   public:
 170     explicit
 171     __fundamental_type_info(const char* __n) : std::type_info(__n) { }
 172
 173     virtual
 174     ~__fundamental_type_info();
 175   };
 176
 177   // Type information for array objects.
 178   class __array_type_info : public std::type_info
 179   {
 180   public:
 181     explicit
 182     __array_type_info(const char* __n) : std::type_info(__n) { }
 183
 184     virtual
 185     ~__array_type_info();
 186   };
 187
 188   // Type information for functions (both member and non-member).
 189   class __function_type_info : public std::type_info
 190   {
 191   public:
 192     explicit
 193     __function_type_info(const char* __n) : std::type_info(__n) { }
 194
 195     virtual
 196     ~__function_type_info();
 197
 198   protected:
 199     // Implementation defined member function.
 200     virtual bool
 201     __is_function_p() const;
 202   };
 203
 204   // Type information for enumerations.
 205   class __enum_type_info : public std::type_info
 206   {
 207   public:
 208     explicit
 209     __enum_type_info(const char* __n) : std::type_info(__n) { }
 210
 211     virtual
 212     ~__enum_type_info();
 213   };
 214
 215   // Common type information for simple pointers and pointers to member.
 216   class __pbase_type_info : public std::type_info
 217   {
 218   public:
 219     unsigned int                __flags; // Qualification of the target object.
 220     const std::type_info*       __pointee; // Type of pointed to object.
 221
 222     explicit
 223     __pbase_type_info(const char* __n, int __quals,
 224                       const std::type_info* __type)
 225     : std::type_info(__n), __flags(__quals), __pointee(__type)
 226     { }
 227
 228     virtual
 229     ~__pbase_type_info();
 230
 231     // Implementation defined type.
 232     enum __masks
 233       {
 234         __const_mask = 0x1,
 235         __volatile_mask = 0x2,
 236         __restrict_mask = 0x4,
 237         __incomplete_mask = 0x8,
 238         __incomplete_class_mask = 0x10
 239       };
 240
 241   protected:
 242     __pbase_type_info(const __pbase_type_info&);
 243
 244     __pbase_type_info&
 245     operator=(const __pbase_type_info&);
 246
 247     // Implementation defined member functions.
 248     virtual bool
 249     __do_catch(const std::type_info* __thr_type, void** __thr_obj,
 250                unsigned int __outer) const;
 251
 252     inline virtual bool
 253     __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj,
 254                     unsigned __outer) const;
 255   };
 256
 257   // Type information for simple pointers.
 258   class __pointer_type_info : public __pbase_type_info
 259   {
 260   public:
 261     explicit
 262     __pointer_type_info(const char* __n, int __quals,
 263                         const std::type_info* __type)
 264     : __pbase_type_info (__n, __quals, __type) { }
 265
 266
 267     virtual
 268     ~__pointer_type_info();
 269
 270   protected:
 271     // Implementation defined member functions.
 272     virtual bool
 273     __is_pointer_p() const;
 274
 275     virtual bool
 276     __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj,
 277                     unsigned __outer) const;
 278   };
 279
 280   class __class_type_info;
 281
 282   // Type information for a pointer to member variable.
 283   class __pointer_to_member_type_info : public __pbase_type_info
 284   {
 285   public:
 286     __class_type_info* __context;   // Class of the member.
 287
 288     explicit
 289     __pointer_to_member_type_info(const char* __n, int __quals,
 290                                   const std::type_info* __type,
 291                                   __class_type_info* __klass)
 292     : __pbase_type_info(__n, __quals, __type), __context(__klass) { }
 293
 294     virtual
 295     ~__pointer_to_member_type_info();
 296
 297   protected:
 298     __pointer_to_member_type_info(const __pointer_to_member_type_info&);
 299
 300     __pointer_to_member_type_info&
 301     operator=(const __pointer_to_member_type_info&);
 302
 303     // Implementation defined member function.
 304     virtual bool
 305     __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj,
 306                     unsigned __outer) const;
 307   };
 308
 309   // Helper class for __vmi_class_type.
 310   class __base_class_type_info
 311   {
 312   public:
 313     const __class_type_info*    __base_type;  // Base class type.
 314     long                        __offset_flags;  // Offset and info.
 315
 316     enum __offset_flags_masks
 317       {
 318         __virtual_mask = 0x1,
 319         __public_mask = 0x2,
 320         __hwm_bit = 2,
 321         __offset_shift = 8          // Bits to shift offset.
 322       };
 323
 324     // Implementation defined member functions.
 325     bool
 326     __is_virtual_p() const
 327     { return __offset_flags & __virtual_mask; }
 328
 329     bool
 330     __is_public_p() const
 331     { return __offset_flags & __public_mask; }
 332
 333     ptrdiff_t
 334     __offset() const
 335     {
 336       // This shift, being of a signed type, is implementation
 337       // defined. GCC implements such shifts as arithmetic, which is
 338       // what we want.
 339       return static_cast<ptrdiff_t>(__offset_flags) >> __offset_shift;
 340     }
 341   };
 342
 343   // Type information for a class.
 344   class __class_type_info : public std::type_info
 345   {
 346   public:
 347     explicit
 348     __class_type_info (const char *__n) : type_info(__n) { }
 349
 350     virtual
 351     ~__class_type_info ();
 352
 353     // Implementation defined types.
 354     // The type sub_kind tells us about how a base object is contained
 355     // within a derived object. We often do this lazily, hence the
 356     // UNKNOWN value. At other times we may use NOT_CONTAINED to mean
 357     // not publicly contained.
 358     enum __sub_kind
 359       {
 360         // We have no idea.
 361         __unknown = 0,
 362
 363         // Not contained within us (in some circumstances this might
 364         // mean not contained publicly)
 365         __not_contained,
 366
 367         // Contained ambiguously.
 368         __contained_ambig,
 369
 370         // Via a virtual path.
 371         __contained_virtual_mask = __base_class_type_info::__virtual_mask,
 372
 373         // Via a public path.
 374         __contained_public_mask = __base_class_type_info::__public_mask,
 375
 376         // Contained within us.
 377         __contained_mask = 1 << __base_class_type_info::__hwm_bit,
 378
 379         __contained_private = __contained_mask,
 380         __contained_public = __contained_mask | __contained_public_mask
 381       };
 382
 383     struct __upcast_result;
 384     struct __dyncast_result;
 385
 386   protected:
 387     // Implementation defined member functions.
 388     virtual bool
 389     __do_upcast(const __class_type_info* __dst_type, void**__obj_ptr) const;
 390
 391     virtual bool
 392     __do_catch(const type_info* __thr_type, void** __thr_obj,
 393                unsigned __outer) const;
 394
 395   public:
 396     // Helper for upcast. See if DST is us, or one of our bases.
 397     // Return false if not found, true if found.
 398     virtual bool
 399     __do_upcast(const __class_type_info* __dst, const void* __obj,
 400                 __upcast_result& __restrict __result) const;
 401
 402     // Indicate whether SRC_PTR of type SRC_TYPE is contained publicly
 403     // within OBJ_PTR. OBJ_PTR points to a base object of our type,
 404     // which is the destination type. SRC2DST indicates how SRC
 405     // objects might be contained within this type.  If SRC_PTR is one
 406     // of our SRC_TYPE bases, indicate the virtuality. Returns
 407     // not_contained for non containment or private containment.
 408     inline __sub_kind
 409     __find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
 410                       const __class_type_info* __src_type,
 411                       const void* __src_ptr) const;
 412
 413     // Helper for dynamic cast. ACCESS_PATH gives the access from the
 414     // most derived object to this base. DST_TYPE indicates the
 415     // desired type we want. OBJ_PTR points to a base of our type
 416     // within the complete object. SRC_TYPE indicates the static type
 417     // started from and SRC_PTR points to that base within the most
 418     // derived object. Fill in RESULT with what we find. Return true
 419     // if we have located an ambiguous match.
 420     virtual bool
 421     __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path,
 422                  const __class_type_info* __dst_type, const void* __obj_ptr,
 423                  const __class_type_info* __src_type, const void* __src_ptr,
 424                  __dyncast_result& __result) const;
 425
 426     // Helper for find_public_subobj. SRC2DST indicates how SRC_TYPE
 427     // bases are inherited by the type started from -- which is not
 428     // necessarily the current type. The current type will be a base
 429     // of the destination type.  OBJ_PTR points to the current base.
 430     virtual __sub_kind
 431     __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
 432                          const __class_type_info* __src_type,
 433                          const void* __src_ptr) const;
 434   };
 435
 436   // Type information for a class with a single non-virtual base.
 437   class __si_class_type_info : public __class_type_info
 438   {
 439   public:
 440     const __class_type_info* __base_type;
 441
 442     explicit
 443     __si_class_type_info(const char *__n, const __class_type_info *__base)
 444     : __class_type_info(__n), __base_type(__base) { }
 445
 446     virtual
 447     ~__si_class_type_info();
 448
 449   protected:
 450     __si_class_type_info(const __si_class_type_info&);
 451
 452     __si_class_type_info&
 453     operator=(const __si_class_type_info&);
 454
 455     // Implementation defined member functions.
 456     virtual bool
 457     __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path,
 458                  const __class_type_info* __dst_type, const void* __obj_ptr,
 459                  const __class_type_info* __src_type, const void* __src_ptr,
 460                  __dyncast_result& __result) const;
 461
 462     virtual __sub_kind
 463     __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
 464                          const __class_type_info* __src_type,
 465                          const void* __sub_ptr) const;
 466
 467     virtual bool
 468     __do_upcast(const __class_type_info*__dst, const void*__obj,
 469                 __upcast_result& __restrict __result) const;
 470   };
 471
 472   // Type information for a class with multiple and/or virtual bases.
 473   class __vmi_class_type_info : public __class_type_info
 474   {
 475   public:
 476     unsigned int                __flags;  // Details about the class hierarchy.
 477     unsigned int                __base_count;  // Number of direct bases.
 478
 479     // The array of bases uses the trailing array struct hack so this
 480     // class is not constructable with a normal constructor. It is
 481     // internally generated by the compiler.
 482     __base_class_type_info      __base_info[1];  // Array of bases.
 483
 484     explicit
 485     __vmi_class_type_info(const char* __n, int ___flags)
 486     : __class_type_info(__n), __flags(___flags), __base_count(0) { }
 487
 488     virtual
 489     ~__vmi_class_type_info();
 490
 491     // Implementation defined types.
 492     enum __flags_masks
 493       {
 494         __non_diamond_repeat_mask = 0x1, // Distinct instance of repeated base.
 495         __diamond_shaped_mask = 0x2, // Diamond shaped multiple inheritance.
 496         __flags_unknown_mask = 0x10
 497       };
 498
 499   protected:
 500     // Implementation defined member functions.
 501     virtual bool
 502     __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path,
 503                  const __class_type_info* __dst_type, const void* __obj_ptr,
 504                  const __class_type_info* __src_type, const void* __src_ptr,
 505                  __dyncast_result& __result) const;
 506
 507     virtual __sub_kind
 508     __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
 509                          const __class_type_info* __src_type,
 510                          const void* __src_ptr) const;
 511
 512     virtual bool
 513     __do_upcast(const __class_type_info* __dst, const void* __obj,
 514                 __upcast_result& __restrict __result) const;
 515   };
 516
 517   // Dynamic cast runtime.
 518   // src2dst has the following possible values
 519   //  >-1: src_type is a unique public non-virtual base of dst_type
 520   //       dst_ptr + src2dst == src_ptr
 521   //   -1: unspecified relationship
 522   //   -2: src_type is not a public base of dst_type
 523   //   -3: src_type is a multiple public non-virtual base of dst_type
 524   extern "C" void*
 525   __dynamic_cast(const void* __src_ptr, // Starting object.
 526                  const __class_type_info* __src_type, // Static type of object.
 527                  const __class_type_info* __dst_type, // Desired target type.
 528                  ptrdiff_t __src2dst); // How src and dst are related.
 529
 530
 531   // Returns the type_info for the currently handled exception [15.3/8], or
 532   // null if there is none.
 533   extern "C" std::type_info*
 534   __cxa_current_exception_type();
 535
 536   // A magic placeholder class that can be caught by reference
 537   // to recognize foreign exceptions.
 538   class __foreign_exception
 539   {
 540     virtual ~__foreign_exception() throw();
 541     virtual void __pure_dummy() = 0; // prevent catch by value
 542   };
 543
 544 } // namespace __cxxabiv1
 545
 546 // User programs should use the alias `abi'.
 547 namespace abi = __cxxabiv1;
 548
 549 #endif // __cplusplus
 550
 551 #pragma GCC visibility pop
 552
 553 #endif // __CXXABI_H