src/common/module.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/module.cpp
   3 // Purpose:     Modules initialization/destruction
   4 // Author:      Wolfram Gloger/adapted by Guilhem Lavaux
   5 // Modified by:
   6 // Created:     04/11/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Wolfram Gloger and Guilhem Lavaux
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // For compilers that support precompilation, includes "wx.h".
  13 #include "wx/wxprec.h"
  14
  15 #ifdef __BORLANDC__
  16     #pragma hdrstop
  17 #endif
  18
  19 #include "wx/module.h"
  20
  21 #ifndef WX_PRECOMP
  22     #include "wx/hash.h"
  23     #include "wx/intl.h"
  24     #include "wx/log.h"
  25 #endif
  26
  27 #include "wx/listimpl.cpp"
  28
  29 #define TRACE_MODULE _T("module")
  30
  31 WX_DEFINE_LIST(wxModuleList)
  32
  33 IMPLEMENT_CLASS(wxModule, wxObject)
  34
  35 wxModuleList wxModule::m_modules;
  36
  37 void wxModule::RegisterModule(wxModule* module)
  38 {
  39     module->m_state = State_Registered;
  40     m_modules.Append(module);
  41 }
  42
  43 void wxModule::UnregisterModule(wxModule* module)
  44 {
  45     m_modules.DeleteObject(module);
  46     delete module;
  47 }
  48
  49 // Collect up all module-derived classes, create an instance of each,
  50 // and register them.
  51 void wxModule::RegisterModules()
  52 {
  53     for (wxClassInfo::const_iterator it  = wxClassInfo::begin_classinfo(),
  54                                      end = wxClassInfo::end_classinfo();
  55          it != end; ++it)
  56     {
  57         const wxClassInfo* classInfo = *it;
  58
  59         if ( classInfo->IsKindOf(CLASSINFO(wxModule)) &&
  60              (classInfo != (& (wxModule::ms_classInfo))) )
  61         {
  62             wxLogTrace(TRACE_MODULE, wxT("Registering module %s"),
  63                        classInfo->GetClassName());
  64             wxModule* module = (wxModule *)classInfo->CreateObject();
  65             wxModule::RegisterModule(module);
  66         }
  67     }
  68 }
  69
  70 bool wxModule::DoInitializeModule(wxModule *module,
  71                                   wxModuleList &initializedModules)
  72 {
  73     if ( module->m_state == State_Initializing )
  74     {
  75         wxLogError(_("Circular dependency involving module \"%s\" detected."),
  76                    module->GetClassInfo()->GetClassName());
  77         return false;
  78     }
  79
  80     module->m_state = State_Initializing;
  81
  82     // translate named dependencies to the normal ones first
  83     if ( !module->ResolveNamedDependencies() )
  84       return false;
  85
  86     const wxArrayClassInfo& dependencies = module->m_dependencies;
  87
  88     // satisfy module dependencies by loading them before the current module
  89     for ( unsigned int i = 0; i < dependencies.size(); ++i )
  90     {
  91         wxClassInfo * cinfo = dependencies[i];
  92
  93         // Check if the module is already initialized
  94         wxModuleList::compatibility_iterator node;
  95         for ( node = initializedModules.GetFirst(); node; node = node->GetNext() )
  96         {
  97             if ( node->GetData()->GetClassInfo() == cinfo )
  98                 break;
  99         }
 100
 101         if ( node )
 102         {
 103             // this dependency is already initialized, nothing to do
 104             continue;
 105         }
 106
 107         // find the module in the registered modules list
 108         for ( node = m_modules.GetFirst(); node; node = node->GetNext() )
 109         {
 110             wxModule *moduleDep = node->GetData();
 111             if ( moduleDep->GetClassInfo() == cinfo )
 112             {
 113                 if ( !DoInitializeModule(moduleDep, initializedModules ) )
 114                 {
 115                     // failed to initialize a dependency, so fail this one too
 116                     return false;
 117                 }
 118
 119                 break;
 120             }
 121         }
 122
 123         if ( !node )
 124         {
 125             wxLogError(_("Dependency \"%s\" of module \"%s\" doesn't exist."),
 126                        cinfo->GetClassName(),
 127                        module->GetClassInfo()->GetClassName());
 128             return false;
 129         }
 130     }
 131
 132     if ( !module->Init() )
 133     {
 134         wxLogError(_("Module \"%s\" initialization failed"),
 135                    module->GetClassInfo()->GetClassName());
 136         return false;
 137     }
 138
 139     wxLogTrace(TRACE_MODULE, wxT("Module \"%s\" initialized"),
 140                module->GetClassInfo()->GetClassName());
 141
 142     module->m_state = State_Initialized;
 143     initializedModules.Append(module);
 144
 145     return true;
 146 }
 147
 148 // Initialize user-defined modules
 149 bool wxModule::InitializeModules()
 150 {
 151     wxModuleList initializedModules;
 152
 153     for ( wxModuleList::compatibility_iterator node = m_modules.GetFirst();
 154           node;
 155           node = node->GetNext() )
 156     {
 157         wxModule *module = node->GetData();
 158
 159         // the module could have been already initialized as dependency of
 160         // another one
 161         if ( module->m_state == State_Registered )
 162         {
 163             if ( !DoInitializeModule( module, initializedModules ) )
 164             {
 165                 // failed to initialize all modules, so clean up the already
 166                 // initialized ones
 167                 DoCleanUpModules(initializedModules);
 168
 169                 return false;
 170             }
 171         }
 172     }
 173
 174     // remember the real initialisation order
 175     m_modules = initializedModules;
 176
 177     return true;
 178 }
 179
 180 // Clean up all currently initialized modules
 181 void wxModule::DoCleanUpModules(const wxModuleList& modules)
 182 {
 183     // cleanup user-defined modules in the reverse order compared to their
 184     // initialization -- this ensures that dependencies are respected
 185     for ( wxModuleList::compatibility_iterator node = modules.GetLast();
 186           node;
 187           node = node->GetPrevious() )
 188     {
 189         wxLogTrace(TRACE_MODULE, wxT("Cleanup module %s"),
 190                    node->GetData()->GetClassInfo()->GetClassName());
 191
 192         wxModule * module = node->GetData();
 193
 194         wxASSERT_MSG( module->m_state == State_Initialized,
 195                         _T("not initialized module being cleaned up") );
 196
 197         module->Exit();
 198         module->m_state = State_Registered;
 199     }
 200
 201     // clear all modules, even the non-initialized ones
 202     WX_CLEAR_LIST(wxModuleList, m_modules);
 203 }
 204
 205 bool wxModule::ResolveNamedDependencies()
 206 {
 207     // first resolve required dependencies
 208     for ( size_t i = 0; i < m_namedDependencies.size(); ++i )
 209     {
 210         wxClassInfo *info = wxClassInfo::FindClass(m_namedDependencies[i]);
 211
 212         if ( !info )
 213         {
 214             // required dependency not found
 215             return false;
 216         }
 217
 218         // add it even if it is not derived from wxModule because
 219         // DoInitializeModule() will make sure a module with the same class
 220         // info exists and fail if it doesn't
 221         m_dependencies.Add(info);
 222     }
 223
 224     return true;
 225 }