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* wxVariantToObjectConverterwxObject ( wxxVariant &data )
  48 { return data.wxTEMPLATED_MEMBER_CALL(Get , wxObject*) ; }
  49  wxObject* wxVariantOfPtrToObjectConverterwxObject ( wxxVariant &data )
  50 { return &data.wxTEMPLATED_MEMBER_CALL(Get , wxObject) ; }
  51  wxxVariant wxObjectToVariantConverterwxObject ( wxObject *data )
  52  { return wxxVariant( dynamic_cast<wxObject*> (data)  ) ; }
  53  wxClassInfo wxObject::ms_classInfo(ms_classParents , wxEmptyString , wxT("wxObject"),
  54             (int) sizeof(wxObject),                              \
  55             (wxObjectConstructorFn) 0   ,
  56             NULL,NULL,0 , 0 ,
  57             0 , wxVariantOfPtrToObjectConverterwxObject , wxVariantToObjectConverterwxObject , wxObjectToVariantConverterwxObject);
  58  template<> void wxStringReadValue(const wxString & , wxObject * & ){ wxFAIL_MSG("unreachable"); }
  59  template<> void wxStringWriteValue(wxString & , wxObject* const & ){ wxFAIL_MSG("unreachable"); }
  60  template<> void wxStringReadValue(const wxString & , wxObject & ){ wxFAIL_MSG("unreachable"); }
  61  template<> void wxStringWriteValue(wxString & , wxObject const & ){ wxFAIL_MSG("unreachable"); }
  62  wxClassTypeInfo s_typeInfo(wxT_OBJECT_PTR , &wxObject::ms_classInfo , NULL , NULL , typeid(wxObject*).name() ) ;
  63  wxClassTypeInfo s_typeInfowxObject(wxT_OBJECT , &wxObject::ms_classInfo , NULL , NULL , typeid(wxObject).name() ) ;
  64 #else
  65 wxClassInfo wxObject::ms_classInfo( wxT("wxObject"), 0, 0,
  66                                         (int) sizeof(wxObject),
  67                                         (wxObjectConstructorFn) 0 );
  68 #endif
  69
  70 // restore optimizations
  71 #if defined __VISUALC__ && __VISUALC__ >= 1300
  72     #pragma optimize("", on)
  73 #endif
  74
  75 wxClassInfo* wxClassInfo::sm_first = NULL;
  76 wxHashTable* wxClassInfo::sm_classTable = NULL;
  77
  78 // when using XTI, this method is already implemented inline inside
  79 // DECLARE_DYNAMIC_CLASS but otherwise we intentionally make this function
  80 // non-inline because this allows us to have a non-inline virtual function in
  81 // all wx classes and this solves linking problems for HP-UX native toolchain
  82 // and possibly others (we could make dtor non-inline as well but it's more
  83 // useful to keep it inline than this function)
  84 #if !wxUSE_EXTENDED_RTTI
  85
  86 wxClassInfo *wxObject::GetClassInfo() const
  87 {
  88     return &wxObject::ms_classInfo;
  89 }
  90
  91 #endif // wxUSE_EXTENDED_RTTI
  92
  93 // this variable exists only so that we can avoid 'always true/false' warnings
  94 const bool wxFalse = false;
  95
  96 // Is this object a kind of (a subclass of) 'info'?
  97 // E.g. is wxWindow a kind of wxObject?
  98 // Go from this class to superclass, taking into account
  99 // two possible base classes.
 100 bool wxObject::IsKindOf(const wxClassInfo *info) const
 101 {
 102     const wxClassInfo *thisInfo = GetClassInfo();
 103     return (thisInfo) ? thisInfo->IsKindOf(info) : false ;
 104 }
 105
 106 #if wxUSE_MEMORY_TRACING && defined( new )
 107     #undef new
 108 #endif
 109
 110
 111 #ifdef _WX_WANT_NEW_SIZET_WXCHAR_INT
 112 void *wxObject::operator new ( size_t size, const wxChar *fileName, int lineNum )
 113 {
 114     return wxDebugAlloc(size, (wxChar*) fileName, lineNum, true);
 115 }
 116 #endif
 117
 118 #ifdef _WX_WANT_DELETE_VOID
 119 void wxObject::operator delete ( void *buf )
 120 {
 121     wxDebugFree(buf);
 122 }
 123 #endif
 124
 125 #ifdef _WX_WANT_DELETE_VOID_CONSTCHAR_SIZET
 126 void wxObject::operator delete ( void *buf, const char *_fname, size_t _line )
 127 {
 128     wxDebugFree(buf);
 129 }
 130 #endif
 131
 132 #ifdef _WX_WANT_DELETE_VOID_WXCHAR_INT
 133 void wxObject::operator delete ( void *buf, const wxChar *WXUNUSED(fileName), int WXUNUSED(lineNum) )
 134 {
 135      wxDebugFree(buf);
 136 }
 137 #endif
 138
 139 #ifdef _WX_WANT_ARRAY_NEW_SIZET_WXCHAR_INT
 140 void *wxObject::operator new[] ( size_t size, const wxChar* fileName, int lineNum )
 141 {
 142     return wxDebugAlloc(size, (wxChar*) fileName, lineNum, true, true);
 143 }
 144 #endif
 145
 146 #ifdef _WX_WANT_ARRAY_DELETE_VOID
 147 void wxObject::operator delete[] ( void *buf )
 148 {
 149     wxDebugFree(buf, true);
 150 }
 151 #endif
 152
 153 #ifdef _WX_WANT_ARRAY_DELETE_VOID_WXCHAR_INT
 154 void wxObject::operator delete[] (void * buf, const wxChar*  WXUNUSED(fileName), int WXUNUSED(lineNum) )
 155 {
 156     wxDebugFree(buf, true);
 157 }
 158 #endif
 159
 160
 161 // ----------------------------------------------------------------------------
 162 // wxClassInfo
 163 // ----------------------------------------------------------------------------
 164
 165 wxClassInfo::~wxClassInfo()
 166 {
 167     // remove this object from the linked list of all class infos: if we don't
 168     // do it, loading/unloading a DLL containing static wxClassInfo objects is
 169     // not going to work
 170     if ( this == sm_first )
 171     {
 172         sm_first = m_next;
 173     }
 174     else
 175     {
 176         wxClassInfo *info = sm_first;
 177         while (info)
 178         {
 179             if ( info->m_next == this )
 180             {
 181                 info->m_next = m_next;
 182                 break;
 183             }
 184
 185             info = info->m_next;
 186         }
 187     }
 188     Unregister();
 189 }
 190
 191 wxClassInfo *wxClassInfo::FindClass(const wxString& className)
 192 {
 193     if ( sm_classTable )
 194     {
 195         return (wxClassInfo *)wxClassInfo::sm_classTable->Get(className);
 196     }
 197     else
 198     {
 199         for ( wxClassInfo *info = sm_first; info ; info = info->m_next )
 200         {
 201             if ( className == info->GetClassName() )
 202                 return info;
 203         }
 204
 205         return NULL;
 206     }
 207 }
 208
 209 // Reentrance can occur on some platforms (Solaris for one), as the use of hash
 210 // and string objects can cause other modules to load and register classes
 211 // before the original call returns. This is handled by keeping the hash table
 212 // local when it is first created and only assigning it to the global variable
 213 // when the function is ready to return.
 214 //
 215 // That does make the assumption that after the function has completed the
 216 // first time the problem will no longer happen; all the modules it depends on
 217 // will have been loaded. The assumption is checked using the 'entry' variable
 218 // as a reentrance guard, it checks that once the hash table is global it is
 219 // not accessed multiple times simulateously.
 220
 221 void wxClassInfo::Register()
 222 {
 223 #if wxDEBUG_LEVEL
 224     // reentrance guard - see note above
 225     static int entry = 0;
 226 #endif // wxDEBUG_LEVEL
 227
 228     wxHashTable *classTable;
 229
 230     if ( !sm_classTable )
 231     {
 232         // keep the hash local initially, reentrance is possible
 233         classTable = new wxHashTable(wxKEY_STRING);
 234     }
 235     else
 236     {
 237         // guard againt reentrance once the global has been created
 238         wxASSERT_MSG(++entry == 1, wxT("wxClassInfo::Register() reentrance"));
 239         classTable = sm_classTable;
 240     }
 241
 242     // Using IMPLEMENT_DYNAMIC_CLASS() macro twice (which may happen if you
 243     // link any object module twice mistakenly, or link twice against wx shared
 244     // library) will break this function because it will enter an infinite loop
 245     // and eventually die with "out of memory" - as this is quite hard to
 246     // detect if you're unaware of this, try to do some checks here.
 247     wxASSERT_MSG( classTable->Get(m_className) == NULL,
 248         wxString::Format
 249         (
 250             wxT("Class \"%s\" already in RTTI table - have you used IMPLEMENT_DYNAMIC_CLASS() multiple times or linked some object file twice)?"),
 251             m_className
 252         )
 253     );
 254
 255     classTable->Put(m_className, (wxObject *)this);
 256
 257     // if we're using a local hash we need to try to make it global
 258     if ( sm_classTable != classTable )
 259     {
 260         if ( !sm_classTable )
 261         {
 262             // make the hash global
 263             sm_classTable = classTable;
 264         }
 265         else
 266         {
 267             // the gobal hash has already been created by a reentrant call,
 268             // so delete the local hash and try again
 269             delete classTable;
 270             Register();
 271         }
 272     }
 273
 274 #if wxDEBUG_LEVEL
 275     entry = 0;
 276 #endif // wxDEBUG_LEVEL
 277 }
 278
 279 void wxClassInfo::Unregister()
 280 {
 281     if ( sm_classTable )
 282     {
 283         sm_classTable->Delete(m_className);
 284         if ( sm_classTable->GetCount() == 0 )
 285         {
 286             wxDELETE(sm_classTable);
 287         }
 288     }
 289 }
 290
 291 wxObject *wxCreateDynamicObject(const wxString& name)
 292 {
 293 #if wxUSE_DEBUG_CONTEXT
 294     DEBUG_PRINTF(wxObject *wxCreateDynamicObject)
 295 #endif
 296
 297     if ( wxClassInfo::sm_classTable )
 298     {
 299         wxClassInfo *info = (wxClassInfo *)wxClassInfo::sm_classTable->Get(name);
 300         return info ? info->CreateObject() : NULL;
 301     }
 302     else // no sm_classTable yet
 303     {
 304         for ( wxClassInfo *info = wxClassInfo::sm_first;
 305               info;
 306               info = info->m_next )
 307         {
 308             if (info->m_className && wxStrcmp(info->m_className, name) == 0)
 309                 return info->CreateObject();
 310         }
 311
 312         return NULL;
 313     }
 314 }
 315
 316 // iterator interface
 317 wxClassInfo::const_iterator::value_type
 318 wxClassInfo::const_iterator::operator*() const
 319 {
 320     return (wxClassInfo*)m_node->GetData();
 321 }
 322
 323 wxClassInfo::const_iterator& wxClassInfo::const_iterator::operator++()
 324 {
 325     m_node = m_table->Next();
 326     return *this;
 327 }
 328
 329 const wxClassInfo::const_iterator wxClassInfo::const_iterator::operator++(int)
 330 {
 331     wxClassInfo::const_iterator tmp = *this;
 332     m_node = m_table->Next();
 333     return tmp;
 334 }
 335
 336 wxClassInfo::const_iterator wxClassInfo::begin_classinfo()
 337 {
 338     sm_classTable->BeginFind();
 339
 340     return const_iterator(sm_classTable->Next(), sm_classTable);
 341 }
 342
 343 wxClassInfo::const_iterator wxClassInfo::end_classinfo()
 344 {
 345     return const_iterator(NULL, NULL);
 346 }
 347
 348 // ----------------------------------------------------------------------------
 349 // wxObjectRefData
 350 // ----------------------------------------------------------------------------
 351
 352 void wxRefCounter::DecRef()
 353 {
 354     wxASSERT_MSG( m_count > 0, "invalid ref data count" );
 355
 356     if ( --m_count == 0 )
 357         delete this;
 358 }
 359
 360
 361 // ----------------------------------------------------------------------------
 362 // wxObject
 363 // ----------------------------------------------------------------------------
 364
 365 void wxObject::Ref(const wxObject& clone)
 366 {
 367 #if wxUSE_DEBUG_CONTEXT
 368     DEBUG_PRINTF(wxObject::Ref)
 369 #endif
 370
 371     // nothing to be done
 372     if (m_refData == clone.m_refData)
 373         return;
 374
 375     // delete reference to old data
 376     UnRef();
 377
 378     // reference new data
 379     if ( clone.m_refData )
 380     {
 381         m_refData = clone.m_refData;
 382         m_refData->IncRef();
 383     }
 384 }
 385
 386 void wxObject::UnRef()
 387 {
 388     if ( m_refData )
 389     {
 390         m_refData->DecRef();
 391         m_refData = NULL;
 392     }
 393 }
 394
 395 void wxObject::AllocExclusive()
 396 {
 397     if ( !m_refData )
 398     {
 399         m_refData = CreateRefData();
 400     }
 401     else if ( m_refData->GetRefCount() > 1 )
 402     {
 403         // note that ref is not going to be destroyed in this case
 404         const wxObjectRefData* ref = m_refData;
 405         UnRef();
 406
 407         // ... so we can still access it
 408         m_refData = CloneRefData(ref);
 409     }
 410     //else: ref count is 1, we are exclusive owners of m_refData anyhow
 411
 412     wxASSERT_MSG( m_refData && m_refData->GetRefCount() == 1,
 413                   wxT("wxObject::AllocExclusive() failed.") );
 414 }
 415
 416 wxObjectRefData *wxObject::CreateRefData() const
 417 {
 418     // if you use AllocExclusive() you must override this method
 419     wxFAIL_MSG( wxT("CreateRefData() must be overridden if called!") );
 420
 421     return NULL;
 422 }
 423
 424 wxObjectRefData *
 425 wxObject::CloneRefData(const wxObjectRefData * WXUNUSED(data)) const
 426 {
 427     // if you use AllocExclusive() you must override this method
 428     wxFAIL_MSG( wxT("CloneRefData() must be overridden if called!") );
 429
 430     return NULL;
 431 }