src/common/object.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/object.cpp
   3 // Purpose:     wxObject implementation
   4 // Author:      Julian Smart
   5 // Modified by: Ron Lee
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 1998 Julian Smart
   9 //              (c) 2001 Ron Lee <ron@debian.org>
  10 // Licence:     wxWindows licence
  11 /////////////////////////////////////////////////////////////////////////////
  12
  13 // For compilers that support precompilation, includes "wx.h".
  14 #include "wx/wxprec.h"
  15
  16 #ifdef __BORLANDC__
  17     #pragma hdrstop
  18 #endif
  19
  20 #ifndef WX_PRECOMP
  21     #include "wx/object.h"
  22     #include "wx/hash.h"
  23     #include "wx/memory.h"
  24     #include "wx/crt.h"
  25 #endif
  26
  27 #include <string.h>
  28
  29 #if wxUSE_DEBUG_CONTEXT
  30     #if defined(__VISAGECPP__)
  31         #define DEBUG_PRINTF(NAME) { static int raz=0; \
  32             printf( #NAME " %i\n",raz); fflush(stdout); raz++; }
  33     #else
  34         #define DEBUG_PRINTF(NAME)
  35     #endif
  36 #endif // wxUSE_DEBUG_CONTEXT
  37
  38 // we must disable optimizations for VC.NET because otherwise its too eager
  39 // linker discards wxClassInfo objects in release build thus breaking many,
  40 // many things
  41 #if defined __VISUALC__ && __VISUALC__ >= 1300
  42     #pragma optimize("", off)
  43 #endif
  44
  45 #if wxUSE_EXTENDED_RTTI
  46 const wxClassInfo* wxObject::ms_classParents[] = { NULL } ;
  47 wxObject* wxVariantOfPtrToObjectConverterwxObject ( const wxAny &data )
  48 { return wxANY_AS(data, wxObject*); }
  49  wxAny wxObjectToVariantConverterwxObject ( wxObject *data )
  50  { return wxAny( dynamic_cast<wxObject*> (data)  ) ; }
  51
  52  wxClassInfo wxObject::ms_classInfo(ms_classParents , wxEmptyString , wxT("wxObject"),
  53             (int) sizeof(wxObject),                              \
  54             (wxObjectConstructorFn) 0   ,
  55             NULL,NULL,0 , 0 ,
  56             0 , wxVariantOfPtrToObjectConverterwxObject , 0 , wxObjectToVariantConverterwxObject);
  57
  58  template<> void wxStringWriteValue(wxString & , wxObject* const & ){ wxFAIL_MSG("unreachable"); }
  59  template<> void wxStringWriteValue(wxString & , wxObject const & ){ wxFAIL_MSG("unreachable"); }
  60
  61  wxClassTypeInfo s_typeInfo(wxT_OBJECT_PTR , &wxObject::ms_classInfo , NULL , NULL , typeid(wxObject*).name() ) ;
  62  wxClassTypeInfo s_typeInfowxObject(wxT_OBJECT , &wxObject::ms_classInfo , NULL , NULL , typeid(wxObject).name() ) ;
  63 #else
  64 wxClassInfo wxObject::ms_classInfo( wxT("wxObject"), 0, 0,
  65                                         (int) sizeof(wxObject),
  66                                         (wxObjectConstructorFn) 0 );
  67 #endif
  68
  69 // restore optimizations
  70 #if defined __VISUALC__ && __VISUALC__ >= 1300
  71     #pragma optimize("", on)
  72 #endif
  73
  74 wxClassInfo* wxClassInfo::sm_first = NULL;
  75 wxHashTable* wxClassInfo::sm_classTable = NULL;
  76
  77 // when using XTI, this method is already implemented inline inside
  78 // DECLARE_DYNAMIC_CLASS but otherwise we intentionally make this function
  79 // non-inline because this allows us to have a non-inline virtual function in
  80 // all wx classes and this solves linking problems for HP-UX native toolchain
  81 // and possibly others (we could make dtor non-inline as well but it's more
  82 // useful to keep it inline than this function)
  83 #if !wxUSE_EXTENDED_RTTI
  84
  85 wxClassInfo *wxObject::GetClassInfo() const
  86 {
  87     return &wxObject::ms_classInfo;
  88 }
  89
  90 #endif // wxUSE_EXTENDED_RTTI
  91
  92 // this variable exists only so that we can avoid 'always true/false' warnings
  93 const bool wxFalse = false;
  94
  95 // Is this object a kind of (a subclass of) 'info'?
  96 // E.g. is wxWindow a kind of wxObject?
  97 // Go from this class to superclass, taking into account
  98 // two possible base classes.
  99 bool wxObject::IsKindOf(const wxClassInfo *info) const
 100 {
 101     const wxClassInfo *thisInfo = GetClassInfo();
 102     return (thisInfo) ? thisInfo->IsKindOf(info) : false ;
 103 }
 104
 105 #if wxUSE_MEMORY_TRACING && defined( new )
 106     #undef new
 107 #endif
 108
 109
 110 #ifdef _WX_WANT_NEW_SIZET_WXCHAR_INT
 111 void *wxObject::operator new ( size_t size, const wxChar *fileName, int lineNum )
 112 {
 113     return wxDebugAlloc(size, (wxChar*) fileName, lineNum, true);
 114 }
 115 #endif
 116
 117 #ifdef _WX_WANT_DELETE_VOID
 118 void wxObject::operator delete ( void *buf )
 119 {
 120     wxDebugFree(buf);
 121 }
 122 #endif
 123
 124 #ifdef _WX_WANT_DELETE_VOID_CONSTCHAR_SIZET
 125 void wxObject::operator delete ( void *buf, const char *_fname, size_t _line )
 126 {
 127     wxDebugFree(buf);
 128 }
 129 #endif
 130
 131 #ifdef _WX_WANT_DELETE_VOID_WXCHAR_INT
 132 void wxObject::operator delete ( void *buf, const wxChar *WXUNUSED(fileName), int WXUNUSED(lineNum) )
 133 {
 134      wxDebugFree(buf);
 135 }
 136 #endif
 137
 138 #ifdef _WX_WANT_ARRAY_NEW_SIZET_WXCHAR_INT
 139 void *wxObject::operator new[] ( size_t size, const wxChar* fileName, int lineNum )
 140 {
 141     return wxDebugAlloc(size, (wxChar*) fileName, lineNum, true, true);
 142 }
 143 #endif
 144
 145 #ifdef _WX_WANT_ARRAY_DELETE_VOID
 146 void wxObject::operator delete[] ( void *buf )
 147 {
 148     wxDebugFree(buf, true);
 149 }
 150 #endif
 151
 152 #ifdef _WX_WANT_ARRAY_DELETE_VOID_WXCHAR_INT
 153 void wxObject::operator delete[] (void * buf, const wxChar*  WXUNUSED(fileName), int WXUNUSED(lineNum) )
 154 {
 155     wxDebugFree(buf, true);
 156 }
 157 #endif
 158
 159
 160 // ----------------------------------------------------------------------------
 161 // wxClassInfo
 162 // ----------------------------------------------------------------------------
 163
 164 wxClassInfo::~wxClassInfo()
 165 {
 166     // remove this object from the linked list of all class infos: if we don't
 167     // do it, loading/unloading a DLL containing static wxClassInfo objects is
 168     // not going to work
 169     if ( this == sm_first )
 170     {
 171         sm_first = m_next;
 172     }
 173     else
 174     {
 175         wxClassInfo *info = sm_first;
 176         while (info)
 177         {
 178             if ( info->m_next == this )
 179             {
 180                 info->m_next = m_next;
 181                 break;
 182             }
 183
 184             info = info->m_next;
 185         }
 186     }
 187     Unregister();
 188 }
 189
 190 wxClassInfo *wxClassInfo::FindClass(const wxString& className)
 191 {
 192     if ( sm_classTable )
 193     {
 194         return (wxClassInfo *)wxClassInfo::sm_classTable->Get(className);
 195     }
 196     else
 197     {
 198         for ( wxClassInfo *info = sm_first; info ; info = info->m_next )
 199         {
 200             if ( className == info->GetClassName() )
 201                 return info;
 202         }
 203
 204         return NULL;
 205     }
 206 }
 207
 208 // Reentrance can occur on some platforms (Solaris for one), as the use of hash
 209 // and string objects can cause other modules to load and register classes
 210 // before the original call returns. This is handled by keeping the hash table
 211 // local when it is first created and only assigning it to the global variable
 212 // when the function is ready to return.
 213 //
 214 // That does make the assumption that after the function has completed the
 215 // first time the problem will no longer happen; all the modules it depends on
 216 // will have been loaded. The assumption is checked using the 'entry' variable
 217 // as a reentrance guard, it checks that once the hash table is global it is
 218 // not accessed multiple times simulateously.
 219
 220 void wxClassInfo::Register()
 221 {
 222 #if wxDEBUG_LEVEL
 223     // reentrance guard - see note above
 224     static int entry = 0;
 225 #endif // wxDEBUG_LEVEL
 226
 227     wxHashTable *classTable;
 228
 229     if ( !sm_classTable )
 230     {
 231         // keep the hash local initially, reentrance is possible
 232         classTable = new wxHashTable(wxKEY_STRING);
 233     }
 234     else
 235     {
 236         // guard againt reentrance once the global has been created
 237         wxASSERT_MSG(++entry == 1, wxT("wxClassInfo::Register() reentrance"));
 238         classTable = sm_classTable;
 239     }
 240
 241     // Using IMPLEMENT_DYNAMIC_CLASS() macro twice (which may happen if you
 242     // link any object module twice mistakenly, or link twice against wx shared
 243     // library) will break this function because it will enter an infinite loop
 244     // and eventually die with "out of memory" - as this is quite hard to
 245     // detect if you're unaware of this, try to do some checks here.
 246     wxASSERT_MSG( classTable->Get(m_className) == NULL,
 247         wxString::Format
 248         (
 249             wxT("Class \"%s\" already in RTTI table - have you used IMPLEMENT_DYNAMIC_CLASS() multiple times or linked some object file twice)?"),
 250             m_className
 251         )
 252     );
 253
 254     classTable->Put(m_className, (wxObject *)this);
 255
 256     // if we're using a local hash we need to try to make it global
 257     if ( sm_classTable != classTable )
 258     {
 259         if ( !sm_classTable )
 260         {
 261             // make the hash global
 262             sm_classTable = classTable;
 263         }
 264         else
 265         {
 266             // the gobal hash has already been created by a reentrant call,
 267             // so delete the local hash and try again
 268             delete classTable;
 269             Register();
 270         }
 271     }
 272
 273 #if wxDEBUG_LEVEL
 274     entry = 0;
 275 #endif // wxDEBUG_LEVEL
 276 }
 277
 278 void wxClassInfo::Unregister()
 279 {
 280     if ( sm_classTable )
 281     {
 282         sm_classTable->Delete(m_className);
 283         if ( sm_classTable->GetCount() == 0 )
 284         {
 285             wxDELETE(sm_classTable);
 286         }
 287     }
 288 }
 289
 290 wxObject *wxCreateDynamicObject(const wxString& name)
 291 {
 292 #if wxUSE_DEBUG_CONTEXT
 293     DEBUG_PRINTF(wxObject *wxCreateDynamicObject)
 294 #endif
 295
 296     if ( wxClassInfo::sm_classTable )
 297     {
 298         wxClassInfo *info = (wxClassInfo *)wxClassInfo::sm_classTable->Get(name);
 299         return info ? info->CreateObject() : NULL;
 300     }
 301     else // no sm_classTable yet
 302     {
 303         for ( wxClassInfo *info = wxClassInfo::sm_first;
 304               info;
 305               info = info->m_next )
 306         {
 307             if (info->m_className && wxStrcmp(info->m_className, name) == 0)
 308                 return info->CreateObject();
 309         }
 310
 311         return NULL;
 312     }
 313 }
 314
 315 // iterator interface
 316 wxClassInfo::const_iterator::value_type
 317 wxClassInfo::const_iterator::operator*() const
 318 {
 319     return (wxClassInfo*)m_node->GetData();
 320 }
 321
 322 wxClassInfo::const_iterator& wxClassInfo::const_iterator::operator++()
 323 {
 324     m_node = m_table->Next();
 325     return *this;
 326 }
 327
 328 const wxClassInfo::const_iterator wxClassInfo::const_iterator::operator++(int)
 329 {
 330     wxClassInfo::const_iterator tmp = *this;
 331     m_node = m_table->Next();
 332     return tmp;
 333 }
 334
 335 wxClassInfo::const_iterator wxClassInfo::begin_classinfo()
 336 {
 337     sm_classTable->BeginFind();
 338
 339     return const_iterator(sm_classTable->Next(), sm_classTable);
 340 }
 341
 342 wxClassInfo::const_iterator wxClassInfo::end_classinfo()
 343 {
 344     return const_iterator(NULL, NULL);
 345 }
 346
 347 // ----------------------------------------------------------------------------
 348 // wxObjectRefData
 349 // ----------------------------------------------------------------------------
 350
 351 void wxRefCounter::DecRef()
 352 {
 353     wxASSERT_MSG( m_count > 0, "invalid ref data count" );
 354
 355     if ( --m_count == 0 )
 356         delete this;
 357 }
 358
 359
 360 // ----------------------------------------------------------------------------
 361 // wxObject
 362 // ----------------------------------------------------------------------------
 363
 364 void wxObject::Ref(const wxObject& clone)
 365 {
 366 #if wxUSE_DEBUG_CONTEXT
 367     DEBUG_PRINTF(wxObject::Ref)
 368 #endif
 369
 370     // nothing to be done
 371     if (m_refData == clone.m_refData)
 372         return;
 373
 374     // delete reference to old data
 375     UnRef();
 376
 377     // reference new data
 378     if ( clone.m_refData )
 379     {
 380         m_refData = clone.m_refData;
 381         m_refData->IncRef();
 382     }
 383 }
 384
 385 void wxObject::UnRef()
 386 {
 387     if ( m_refData )
 388     {
 389         m_refData->DecRef();
 390         m_refData = NULL;
 391     }
 392 }
 393
 394 void wxObject::AllocExclusive()
 395 {
 396     if ( !m_refData )
 397     {
 398         m_refData = CreateRefData();
 399     }
 400     else if ( m_refData->GetRefCount() > 1 )
 401     {
 402         // note that ref is not going to be destroyed in this case
 403         const wxObjectRefData* ref = m_refData;
 404         UnRef();
 405
 406         // ... so we can still access it
 407         m_refData = CloneRefData(ref);
 408     }
 409     //else: ref count is 1, we are exclusive owners of m_refData anyhow
 410
 411     wxASSERT_MSG( m_refData && m_refData->GetRefCount() == 1,
 412                   wxT("wxObject::AllocExclusive() failed.") );
 413 }
 414
 415 wxObjectRefData *wxObject::CreateRefData() const
 416 {
 417     // if you use AllocExclusive() you must override this method
 418     wxFAIL_MSG( wxT("CreateRefData() must be overridden if called!") );
 419
 420     return NULL;
 421 }
 422
 423 wxObjectRefData *
 424 wxObject::CloneRefData(const wxObjectRefData * WXUNUSED(data)) const
 425 {
 426     // if you use AllocExclusive() you must override this method
 427     wxFAIL_MSG( wxT("CloneRefData() must be overridden if called!") );
 428
 429     return NULL;
 430 }