dlls/msvcrt/cppexcept.h

   1 /*
   2  * msvcrt C++ exception handling
   3  *
   4  * Copyright 2002 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) 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 GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #ifndef __MSVCRT_CPPEXCEPT_H
  22 #define __MSVCRT_CPPEXCEPT_H
  23
  24 #define CXX_FRAME_MAGIC_VC6 0x19930520
  25 #define CXX_FRAME_MAGIC_VC7 0x19930521
  26 #define CXX_FRAME_MAGIC_VC8 0x19930522
  27 #define CXX_EXCEPTION       0xe06d7363
  28
  29 typedef void (*vtable_ptr)(void);
  30
  31 /* type_info object, see cpp.c for implementation */
  32 typedef struct __type_info
  33 {
  34   const vtable_ptr *vtable;
  35   char              *name;        /* Unmangled name, allocated lazily */
  36   char               mangled[32]; /* Variable length, but we declare it large enough for static RTTI */
  37 } type_info;
  38
  39 /* exception object */
  40 typedef struct __exception
  41 {
  42   const vtable_ptr *vtable;
  43   char             *name;    /* Name of this exception, always a new copy for each object */
  44   int               do_free; /* Whether to free 'name' in our dtor */
  45 } exception;
  46
  47 typedef void (*cxx_copy_ctor)(void);
  48
  49 /* offsets for computing the this pointer */
  50 typedef struct
  51 {
  52     int         this_offset;   /* offset of base class this pointer from start of object */
  53     int         vbase_descr;   /* offset of virtual base class descriptor */
  54     int         vbase_offset;  /* offset of this pointer offset in virtual base class descriptor */
  55 } this_ptr_offsets;
  56
  57 /* complete information about a C++ type */
  58 typedef struct __cxx_type_info
  59 {
  60     UINT             flags;        /* flags (see CLASS_* flags below) */
  61     const type_info *type_info;    /* C++ type info */
  62     this_ptr_offsets offsets;      /* offsets for computing the this pointer */
  63     unsigned int     size;         /* object size */
  64     cxx_copy_ctor    copy_ctor;    /* copy constructor */
  65 } cxx_type_info;
  66 #define CLASS_IS_SIMPLE_TYPE          1
  67 #define CLASS_HAS_VIRTUAL_BASE_CLASS  4
  68
  69 /* table of C++ types that apply for a given object */
  70 typedef struct __cxx_type_info_table
  71 {
  72     UINT                 count;     /* number of types */
  73     const cxx_type_info *info[3];   /* variable length, we declare it large enough for static RTTI */
  74 } cxx_type_info_table;
  75
  76 struct __cxx_exception_frame;
  77 struct __cxx_function_descr;
  78
  79 typedef DWORD (*cxx_exc_custom_handler)( PEXCEPTION_RECORD, struct __cxx_exception_frame*,
  80                                          PCONTEXT, EXCEPTION_REGISTRATION_RECORD**,
  81                                          const struct __cxx_function_descr*, int nested_trylevel,
  82                                          EXCEPTION_REGISTRATION_RECORD *nested_frame, DWORD unknown3 );
  83
  84 /* type information for an exception object */
  85 typedef struct __cxx_exception_type
  86 {
  87     UINT                       flags;            /* TYPE_FLAG flags */
  88     void                     (*destructor)(void);/* exception object destructor */
  89     cxx_exc_custom_handler     custom_handler;   /* custom handler for this exception */
  90     const cxx_type_info_table *type_info_table;  /* list of types for this exception object */
  91 } cxx_exception_type;
  92
  93 void WINAPI _CxxThrowException(exception*,const cxx_exception_type*);
  94 int CDECL _XcptFilter(NTSTATUS, PEXCEPTION_POINTERS);
  95
  96 static inline const char *dbgstr_type_info( const type_info *info )
  97 {
  98     if (!info) return "{}";
  99     return wine_dbg_sprintf( "{vtable=%p name=%s (%s)}",
 100                              info->vtable, info->mangled, info->name ? info->name : "" );
 101 }
 102
 103 /* compute the this pointer for a base class of a given type */
 104 static inline void *get_this_pointer( const this_ptr_offsets *off, void *object )
 105 {
 106     void *this_ptr;
 107     int *offset_ptr;
 108
 109     if (!object) return NULL;
 110     this_ptr = (char *)object + off->this_offset;
 111     if (off->vbase_descr >= 0)
 112     {
 113         /* move this ptr to vbase descriptor */
 114         this_ptr = (char *)this_ptr + off->vbase_descr;
 115         /* and fetch additional offset from vbase descriptor */
 116         offset_ptr = (int *)(*(char **)this_ptr + off->vbase_offset);
 117         this_ptr = (char *)this_ptr + *offset_ptr;
 118     }
 119     return this_ptr;
 120 }
 121
 122 #endif /* __MSVCRT_CPPEXCEPT_H */