src/common/dynload.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:         dynload.cpp
   3 // Purpose:      Dynamic loading framework
   4 // Author:       Ron Lee, David Falkinder, Vadim Zeitlin and a cast of 1000's
   5 //               (derived in part from dynlib.cpp (c) 1998 Guilhem Lavaux)
   6 // Modified by:
   7 // Created:      03/12/01
   8 // RCS-ID:       $Id$
   9 // Copyright:    (c) 2001 Ron Lee <ron@debian.org>
  10 // Licence:      wxWindows license
  11 /////////////////////////////////////////////////////////////////////////////
  12
  13 #ifdef __GNUG__
  14 #pragma implementation "dynload.h"
  15 #endif
  16
  17 // ----------------------------------------------------------------------------
  18 // headers
  19 // ----------------------------------------------------------------------------
  20
  21 #include "wx/wxprec.h"
  22
  23 #ifdef __BORLANDC__
  24     #pragma hdrstop
  25 #endif
  26
  27 #if wxUSE_DYNAMIC_LOADER
  28
  29 #ifdef __WINDOWS__
  30     #include "wx/msw/private.h"
  31 #endif
  32
  33 #ifndef WX_PRECOMP
  34     #include "wx/log.h"
  35     #include "wx/intl.h"
  36 #endif
  37
  38 #include "wx/filename.h"        // for SplitPath()
  39 #include "wx/strconv.h"
  40
  41 #include "wx/dynload.h"
  42 #include "wx/module.h"
  43
  44 #if defined(__DARWIN__)
  45 /* Porting notes:
  46  *   The dlopen port is a port from dl_next.xs by Anno Siegel.
  47  *   dl_next.xs is itself a port from dl_dlopen.xs by Paul Marquess.
  48  *   The method used here is just to supply the sun style dlopen etc.
  49  *   functions in terms of Darwin NS*.
  50  */
  51 void *dlopen(const char *path, int mode /* mode is ignored */);
  52 void *dlsym(void *handle, const char *symbol);
  53 int   dlclose(void *handle);
  54 const char *dlerror(void);
  55 #endif
  56
  57 // ============================================================================
  58 // implementation
  59 // ============================================================================
  60
  61 // ---------------------------------------------------------------------------
  62 // wxDynamicLibrary
  63 // ---------------------------------------------------------------------------
  64
  65 //FIXME:  This class isn't really common at all, it should be moved into
  66 //        platform dependent files.
  67
  68 #if defined(__WINDOWS__) || defined(__WXPM__) || defined(__EMX__)
  69     const wxChar *wxDynamicLibrary::ms_dllext = _T(".dll");
  70 #elif defined(__UNIX__)
  71     #if defined(__HPUX__)
  72         const wxChar *wxDynamicLibrary::ms_dllext = _T(".sl");
  73     #else
  74         const wxChar *wxDynamicLibrary::ms_dllext = _T(".so");
  75     #endif
  76 #endif
  77
  78 wxDllType wxDynamicLibrary::GetProgramHandle()
  79 {
  80 #if defined( HAVE_DLOPEN ) && !defined(__EMX__)
  81    return dlopen(0, RTLD_LAZY);
  82 #elif defined (HAVE_SHL_LOAD)
  83    return PROG_HANDLE;
  84 #else
  85    wxFAIL_MSG( wxT("This method is not implemented under Windows or OS/2"));
  86    return 0;
  87 #endif
  88 }
  89
  90 bool wxDynamicLibrary::Load(wxString libname, int flags)
  91 {
  92     wxASSERT_MSG(m_handle == 0, _T("Library already loaded."));
  93
  94     // add the proper extension for the DLL ourselves unless told not to
  95     if ( !(flags & wxDL_VERBATIM) )
  96     {
  97         // and also check that the libname doesn't already have it
  98         wxString ext;
  99         wxFileName::SplitPath(libname, NULL, NULL, &ext);
 100         if ( ext.empty() )
 101         {
 102             libname += GetDllExt();
 103         }
 104     }
 105
 106     // different ways to load a shared library
 107     //
 108     // FIXME: should go to the platform-specific files!
 109 #if defined(__WXMAC__) && !defined(__DARWIN__)
 110     FSSpec      myFSSpec;
 111     Ptr         myMainAddr;
 112     Str255      myErrName;
 113
 114     wxMacFilename2FSSpec( libname , &myFSSpec );
 115
 116     if( GetDiskFragment( &myFSSpec,
 117                          0,
 118                          kCFragGoesToEOF,
 119                          "\p",
 120                          kPrivateCFragCopy,
 121                          &m_handle,
 122                          &myMainAddr,
 123                          myErrName ) != noErr )
 124     {
 125         p2cstr( myErrName );
 126         wxLogSysError( _("Failed to load shared library '%s' Error '%s'"),
 127                        libname.c_str(),
 128                        (char*)myErrName );
 129         m_handle = 0;
 130     }
 131
 132 #elif defined(__WXPM__) || defined(__EMX__)
 133     char    err[256] = "";
 134     DosLoadModule(err, sizeof(err), libname.c_str(), &m_handle);
 135
 136 #elif defined(HAVE_DLOPEN) || defined(__DARWIN__)
 137
 138 #if defined(__VMS) || defined(__DARWIN__)
 139     m_handle = dlopen(libname.c_str(), 0);  // The second parameter is ignored
 140 #else // !__VMS  && !__DARWIN__
 141     int rtldFlags = 0;
 142
 143     if ( flags & wxDL_LAZY )
 144     {
 145         wxASSERT_MSG( (flags & wxDL_NOW) == 0,
 146                       _T("wxDL_LAZY and wxDL_NOW are mutually exclusive.") );
 147 #ifdef RTLD_LAZY
 148         rtldFlags |= RTLD_LAZY;
 149 #else
 150         wxLogDebug(_T("wxDL_LAZY is not supported on this platform"));
 151 #endif
 152     }
 153     else if ( flags & wxDL_NOW )
 154     {
 155 #ifdef RTLD_NOW
 156         rtldFlags |= RTLD_NOW;
 157 #else
 158         wxLogDebug(_T("wxDL_NOW is not supported on this platform"));
 159 #endif
 160     }
 161
 162     if ( flags & wxDL_GLOBAL )
 163     {
 164 #ifdef RTLD_GLOBAL
 165         rtldFlags |= RTLD_GLOBAL;
 166 #else
 167         wxLogDebug(_T("RTLD_GLOBAL is not supported on this platform."));
 168 #endif
 169     }
 170
 171     m_handle = dlopen(libname.fn_str(), rtldFlags);
 172 #endif  // __VMS || __DARWIN__ ?
 173
 174 #elif defined(HAVE_SHL_LOAD)
 175     int shlFlags = 0;
 176
 177     if( flags & wxDL_LAZY )
 178     {
 179         wxASSERT_MSG( (flags & wxDL_NOW) == 0,
 180                       _T("wxDL_LAZY and wxDL_NOW are mutually exclusive.") );
 181         shlFlags |= BIND_DEFERRED;
 182     }
 183     else if( flags & wxDL_NOW )
 184     {
 185         shlFlags |= BIND_IMMEDIATE;
 186     }
 187     m_handle = shl_load(libname.fn_str(), BIND_DEFERRED, 0);
 188
 189 #elif defined(__WINDOWS__)
 190     m_handle = ::LoadLibrary(libname.c_str());
 191 #else
 192     #error  "runtime shared lib support not implemented on this platform"
 193 #endif
 194
 195     if ( m_handle == 0 )
 196     {
 197         wxString msg(_("Failed to load shared library '%s'"));
 198 #if defined(HAVE_DLERROR) && !defined(__EMX__)
 199
 200 #if wxUSE_UNICODE
 201         wxWCharBuffer buffer = wxConvLocal.cMB2WC( dlerror() );
 202         const wxChar *err = buffer;
 203 #else
 204         const wxChar *err = dlerror();
 205 #endif
 206
 207         if( err )
 208             wxLogError( msg, err );
 209 #else
 210         wxLogSysError( msg, libname.c_str() );
 211 #endif
 212     }
 213
 214     return IsLoaded();
 215 }
 216
 217 void wxDynamicLibrary::Unload()
 218 {
 219     if( IsLoaded() )
 220     {
 221 #if defined(__WXPM__) || defined(__EMX__)
 222         DosFreeModule( m_handle );
 223 #elif defined(HAVE_DLOPEN) || defined(__DARWIN__)
 224         dlclose( m_handle );
 225 #elif defined(HAVE_SHL_LOAD)
 226         shl_unload( m_handle );
 227 #elif defined(__WINDOWS__)
 228         ::FreeLibrary( m_handle );
 229 #elif defined(__WXMAC__) && !defined(__DARWIN__)
 230         CloseConnection( (CFragConnectionID*) &m_handle );
 231 #else
 232 #error  "runtime shared lib support not implemented"
 233 #endif
 234         m_handle = 0;
 235     }
 236 }
 237
 238 void *wxDynamicLibrary::GetSymbol(const wxString &name, bool *success) const
 239 {
 240     wxCHECK_MSG( IsLoaded(), NULL,
 241                  _T("Can't load symbol from unloaded library") );
 242
 243     bool     failed = FALSE;
 244     void    *symbol = 0;
 245
 246 #if defined(__WXMAC__) && !defined(__DARWIN__)
 247     Ptr                 symAddress;
 248     CFragSymbolClass    symClass;
 249     Str255              symName;
 250 #if TARGET_CARBON
 251     c2pstrcpy( (StringPtr) symName, name );
 252 #else
 253     strcpy( (char *)symName, name );
 254     c2pstr( (char *)symName );
 255 #endif
 256     if( FindSymbol( dllHandle, symName, &symAddress, &symClass ) == noErr )
 257         symbol = (void *)symAddress;
 258
 259 #elif defined(__WXPM__) || defined(__EMX__)
 260     DosQueryProcAddr( m_handle, 1L, name.c_str(), (PFN*)symbol );
 261
 262 #elif defined(HAVE_DLOPEN) || defined(__DARWIN__)
 263     symbol = dlsym( m_handle, name.fn_str() );
 264
 265 #elif defined(HAVE_SHL_LOAD)
 266     if( shl_findsym( &m_handle, name.fn_str(), TYPE_UNDEFINED, &symbol ) != 0 )
 267         symbol = 0;
 268
 269 #elif defined(__WINDOWS__)
 270     symbol = (void*) ::GetProcAddress( m_handle, name.mb_str() );
 271
 272 #else
 273 #error  "runtime shared lib support not implemented"
 274 #endif
 275
 276     if ( !symbol )
 277     {
 278         wxString msg(_("wxDynamicLibrary failed to GetSymbol '%s'"));
 279 #if defined(HAVE_DLERROR) && !defined(__EMX__)
 280
 281 #if wxUSE_UNICODE
 282         wxWCharBuffer buffer = wxConvLocal.cMB2WC( dlerror() );
 283         const wxChar *err = buffer;
 284 #else
 285         const wxChar *err = dlerror();
 286 #endif
 287
 288         if( err )
 289         {
 290             failed = TRUE;
 291             wxLogError( msg, err );
 292         }
 293 #else
 294         failed = TRUE;
 295         wxLogSysError(_("Couldn't find symbol '%s' in a dynamic library"),
 296                       name.c_str());
 297 #endif
 298     }
 299     if( success )
 300         *success = !failed;
 301
 302     return symbol;
 303 }
 304
 305
 306 // ---------------------------------------------------------------------------
 307 // wxPluginLibrary
 308 // ---------------------------------------------------------------------------
 309
 310
 311 wxDLImports*  wxPluginLibrary::ms_classes = NULL;
 312
 313 class wxPluginLibraryModule : public wxModule
 314 {
 315 public:
 316     wxPluginLibraryModule() { }
 317
 318     // TODO: create ms_classes on demand, why always preallocate it?
 319     virtual bool OnInit()
 320     {
 321         wxPluginLibrary::ms_classes = new wxDLImports(wxKEY_STRING);
 322         wxPluginManager::CreateManifest();
 323         return TRUE;
 324     }
 325
 326     virtual void OnExit()
 327     {
 328         delete wxPluginLibrary::ms_classes;
 329         wxPluginLibrary::ms_classes = NULL;
 330         wxPluginManager::ClearManifest();
 331     }
 332
 333 private:
 334     DECLARE_DYNAMIC_CLASS(wxPluginLibraryModule )
 335 };
 336
 337 IMPLEMENT_DYNAMIC_CLASS(wxPluginLibraryModule, wxModule)
 338
 339
 340 wxPluginLibrary::wxPluginLibrary(const wxString &libname, int flags)
 341         : m_linkcount(1)
 342         , m_objcount(0)
 343 {
 344     m_before = wxClassInfo::sm_first;
 345     Load( libname, flags );
 346     m_after = wxClassInfo::sm_first;
 347
 348     if( m_handle != 0 )
 349     {
 350         UpdateClassInfo();
 351         RegisterModules();
 352     }
 353     else
 354     {
 355         // Flag us for deletion
 356         --m_linkcount;
 357     }
 358 }
 359
 360 wxPluginLibrary::~wxPluginLibrary()
 361 {
 362     if( m_handle != 0 )
 363     {
 364         UnregisterModules();
 365         RestoreClassInfo();
 366     }
 367 }
 368
 369 wxPluginLibrary *wxPluginLibrary::RefLib()
 370 {
 371     wxCHECK_MSG( m_linkcount > 0, NULL,
 372                  _T("Library had been already deleted!") );
 373
 374     ++m_linkcount;
 375     return this;
 376 }
 377
 378 bool wxPluginLibrary::UnrefLib()
 379 {
 380     wxASSERT_MSG( m_objcount == 0,
 381                   _T("Library unloaded before all objects were destroyed") );
 382
 383     if ( --m_linkcount == 0 )
 384     {
 385         delete this;
 386         return TRUE;
 387     }
 388
 389     return FALSE;
 390 }
 391
 392 // ------------------------
 393 // Private methods
 394 // ------------------------
 395
 396 void wxPluginLibrary::UpdateClassInfo()
 397 {
 398     wxClassInfo     *info;
 399     wxHashTable     *t = wxClassInfo::sm_classTable;
 400
 401         // FIXME: Below is simply a cut and paste specialisation of
 402         //        wxClassInfo::InitializeClasses.  Once this stabilises,
 403         //        the two should probably be merged.
 404         //
 405         //        Actually it's becoming questionable whether we should merge
 406         //        this info with the main ClassInfo tables since we can nearly
 407         //        handle this completely internally now and it does expose
 408         //        certain (minimal % user_stupidy) risks.
 409
 410     for(info = m_after; info != m_before; info = info->m_next)
 411     {
 412         if( info->m_className )
 413         {
 414             if( t->Get(info->m_className) == 0 )
 415                 t->Put(info->m_className, (wxObject *)info);
 416
 417             // Hash all the class names into a local table too so
 418             // we can quickly find the entry they correspond to.
 419
 420             if( ms_classes->Get(info->m_className) == 0 )
 421                 ms_classes->Put(info->m_className, (wxObject *) this);
 422         }
 423     }
 424
 425     for(info = m_after; info != m_before; info = info->m_next)
 426     {
 427         if( info->m_baseClassName1 )
 428             info->m_baseInfo1 = (wxClassInfo *)t->Get(info->m_baseClassName1);
 429         if( info->m_baseClassName2 )
 430             info->m_baseInfo2 = (wxClassInfo *)t->Get(info->m_baseClassName2);
 431     }
 432 }
 433
 434 void wxPluginLibrary::RestoreClassInfo()
 435 {
 436     wxClassInfo *info;
 437
 438     for(info = m_after; info != m_before; info = info->m_next)
 439     {
 440         wxClassInfo::sm_classTable->Delete(info->m_className);
 441         ms_classes->Delete(info->m_className);
 442     }
 443
 444     if( wxClassInfo::sm_first == m_after )
 445         wxClassInfo::sm_first = m_before;
 446     else
 447     {
 448         info = wxClassInfo::sm_first;
 449         while( info->m_next && info->m_next != m_after ) info = info->m_next;
 450
 451         wxASSERT_MSG( info, _T("ClassInfo from wxPluginLibrary not found on purge"));
 452
 453         info->m_next = m_before;
 454     }
 455 }
 456
 457 void wxPluginLibrary::RegisterModules()
 458 {
 459     // Plugin libraries might have wxModules, Register and initialise them if
 460     // they do.
 461     //
 462     // Note that these classes are NOT included in the reference counting since
 463     // it's implicit that they will be unloaded if and when the last handle to
 464     // the library is.  We do have to keep a copy of the module's pointer
 465     // though, as there is currently no way to Unregister it without it.
 466
 467     wxASSERT_MSG( m_linkcount == 1,
 468                   _T("RegisterModules should only be called for the first load") );
 469
 470     for(wxClassInfo *info = m_after; info != m_before; info = info->m_next)
 471     {
 472         if( info->IsKindOf(CLASSINFO(wxModule)) )
 473         {
 474             wxModule *m = wxDynamicCast(info->CreateObject(), wxModule);
 475
 476             wxASSERT_MSG( m, _T("wxDynamicCast of wxModule failed") );
 477
 478             m_wxmodules.Append(m);
 479             wxModule::RegisterModule(m);
 480         }
 481     }
 482
 483     // FIXME: Likewise this is (well was) very similar to InitializeModules()
 484
 485     for(wxModuleList::Node *node = m_wxmodules.GetFirst(); node; node->GetNext())
 486     {
 487         if( !node->GetData()->Init() )
 488         {
 489             wxLogDebug(_T("wxModule::Init() failed for wxPluginLibrary"));
 490
 491             // XXX: Watch this, a different hash implementation might break it,
 492             //      a good hash implementation would let us fix it though.
 493
 494             // The name of the game is to remove any uninitialised modules and
 495             // let the dtor Exit the rest on shutdown, (which we'll initiate
 496             // shortly).
 497
 498             wxModuleList::Node *oldNode = 0;
 499             do {
 500                 node = node->GetNext();
 501                 delete oldNode;
 502                 wxModule::UnregisterModule( node->GetData() );
 503                 oldNode = node;
 504             } while( node );
 505
 506             --m_linkcount;     // Flag us for deletion
 507             break;
 508         }
 509     }
 510 }
 511
 512 void wxPluginLibrary::UnregisterModules()
 513 {
 514     wxModuleList::Node  *node;
 515
 516     for(node = m_wxmodules.GetFirst(); node; node->GetNext())
 517         node->GetData()->Exit();
 518
 519     for(node = m_wxmodules.GetFirst(); node; node->GetNext())
 520         wxModule::UnregisterModule( node->GetData() );
 521
 522     m_wxmodules.DeleteContents(TRUE);
 523 }
 524
 525
 526 // ---------------------------------------------------------------------------
 527 // wxPluginManager
 528 // ---------------------------------------------------------------------------
 529
 530 wxDLManifest*   wxPluginManager::ms_manifest = NULL;
 531
 532 // ------------------------
 533 // Static accessors
 534 // ------------------------
 535
 536 wxPluginLibrary *
 537 wxPluginManager::LoadLibrary(const wxString &libname, int flags)
 538 {
 539     wxString realname(libname);
 540
 541     if( !(flags & wxDL_VERBATIM) )
 542         realname += wxDynamicLibrary::GetDllExt();
 543
 544     wxPluginLibrary *entry;
 545
 546     if ( flags & wxDL_NOSHARE )
 547     {
 548         entry = NULL;
 549     }
 550     else
 551     {
 552         entry = (wxPluginLibrary*) ms_manifest->Get(realname);
 553     }
 554
 555     if ( entry )
 556     {
 557         wxLogTrace(_T("dll"),
 558                    _T("LoadLibrary(%s): already loaded."), realname.c_str());
 559
 560         entry->RefLib();
 561     }
 562     else
 563     {
 564         entry = new wxPluginLibrary( libname, flags );
 565
 566         if ( entry->IsLoaded() )
 567         {
 568             ms_manifest->Put(realname, (wxObject*) entry);
 569
 570             wxLogTrace(_T("dll"),
 571                        _T("LoadLibrary(%s): loaded ok."), realname.c_str());
 572
 573         }
 574         else
 575         {
 576             wxLogTrace(_T("dll"),
 577                        _T("LoadLibrary(%s): failed to load."), realname.c_str());
 578
 579             // we have created entry just above
 580             if ( !entry->UnrefLib() )
 581             {
 582                 // ... so UnrefLib() is supposed to delete it
 583                 wxFAIL_MSG( _T("Currently linked library is not loaded?") );
 584             }
 585
 586             entry = NULL;
 587         }
 588     }
 589
 590     return entry;
 591 }
 592
 593 bool wxPluginManager::UnloadLibrary(const wxString& libname)
 594 {
 595     wxString realname = libname;
 596
 597     wxPluginLibrary *entry = (wxPluginLibrary*) ms_manifest->Get(realname);
 598
 599     if ( !entry )
 600     {
 601         realname += wxDynamicLibrary::GetDllExt();
 602
 603         entry = (wxPluginLibrary*) ms_manifest->Get(realname);
 604     }
 605
 606     if ( !entry )
 607     {
 608         wxLogDebug(_T("Attempt to unload library '%s' which is not loaded."),
 609                    libname.c_str());
 610
 611         return FALSE;
 612     }
 613
 614     wxLogTrace(_T("dll"), _T("UnloadLibrary(%s)"), realname.c_str());
 615
 616     if ( !entry->UnrefLib() )
 617     {
 618         // not really unloaded yet
 619         return FALSE;
 620     }
 621
 622     ms_manifest->Delete(realname);
 623
 624     return TRUE;
 625 }
 626
 627 #if WXWIN_COMPATIBILITY_2_2
 628 wxPluginLibrary *wxPluginManager::GetObjectFromHandle(wxDllType handle)
 629 {
 630     wxNode  *node;
 631     ms_manifest->BeginFind();
 632
 633     for(node = ms_manifest->Next(); node; node = ms_manifest->Next())
 634         if( ((wxPluginLibrary*)node->GetData())->GetLibHandle() == handle )
 635             return (wxPluginLibrary*)node->GetData();
 636
 637     return NULL;
 638 }
 639 #endif // WXWIN_COMPATIBILITY_2_2
 640
 641 // ------------------------
 642 // Class implementation
 643 // ------------------------
 644
 645 bool wxPluginManager::Load(const wxString &libname, int flags)
 646 {
 647     m_entry = wxPluginManager::LoadLibrary(libname, flags);
 648     return IsLoaded();
 649 }
 650
 651 void wxPluginManager::Unload()
 652 {
 653     wxNode  *node;
 654     ms_manifest->BeginFind();
 655
 656     // It's either this or store the name of the lib just to do this.
 657
 658     for(node = ms_manifest->Next(); node; node = ms_manifest->Next())
 659         if( (wxPluginLibrary*)node->GetData() == m_entry )
 660             break;
 661
 662     if( m_entry && m_entry->UnrefLib() )
 663     {
 664         delete node;
 665         m_entry = 0;
 666     }
 667 }
 668
 669 // ---------------------------------------------------------------------------
 670 // wxDllLoader   (all these methods are static)
 671 // ---------------------------------------------------------------------------
 672
 673 #if WXWIN_COMPATIBILITY_2_2
 674
 675 wxDllType wxDllLoader::LoadLibrary(const wxString &name, bool *success)
 676 {
 677     wxPluginLibrary *p = wxPluginManager::LoadLibrary
 678                          (
 679                             name,
 680                             wxDL_DEFAULT | wxDL_VERBATIM | wxDL_NOSHARE
 681                          );
 682
 683     if ( success )
 684         *success = p != NULL;
 685
 686     return p ? p->GetLibHandle() : 0;
 687 }
 688
 689 void wxDllLoader::UnloadLibrary(wxDllType handle)
 690 {
 691     wxPluginLibrary *p = wxPluginManager::GetObjectFromHandle(handle);
 692
 693     wxCHECK_RET( p, _T("Unloading a library not loaded with wxDllLoader?") );
 694
 695     p->UnrefLib();
 696 }
 697
 698 void *
 699 wxDllLoader::GetSymbol(wxDllType dllHandle, const wxString &name, bool *success)
 700 {
 701     wxPluginLibrary *p = wxPluginManager::GetObjectFromHandle(dllHandle);
 702
 703     if ( !p )
 704     {
 705         wxFAIL_MSG( _T("Using a library not loaded with wxDllLoader?") );
 706
 707         if ( success )
 708             *success = FALSE;
 709
 710         return NULL;
 711     }
 712
 713     return p->GetSymbol(name, success);
 714 }
 715
 716 #endif  // WXWIN_COMPATIBILITY_2_2
 717
 718 #endif  // wxUSE_DYNAMIC_LOADER
 719