added explanatory comment

[wxWidgets.git] / src / common / init.cpp

diff --git a/src/common/init.cpp b/src/common/init.cpp
index 0fa42d7d8f7fda405c2e1cf19e7e720218d753d7..bb5693e4a99e9f650fdc725a78c8d5c8ff1713ab 100644 (file)
--- a/src/common/init.cpp
+++ b/src/common/init.cpp
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////

-// Name:        common/init.cpp
+// Name:        src/common/init.cpp

 // Purpose:     initialisation for the library
 // Author:      Vadim Zeitlin
 // Modified by:
 // Purpose:     initialisation for the library
 // Author:      Vadim Zeitlin
 // Modified by:


@@ -20,112 +20,472 @@
 #include "wx/wxprec.h"
 
 #ifdef    __BORLANDC__
 #include "wx/wxprec.h"
 
 #ifdef    __BORLANDC__

-  #pragma hdrstop
+    #pragma hdrstop

 #endif  //__BORLANDC__
 
 #ifndef WX_PRECOMP
     #include "wx/app.h"
 #endif  //__BORLANDC__
 
 #ifndef WX_PRECOMP
     #include "wx/app.h"

-    #include "wx/debug.h"
+    #include "wx/filefn.h"
+    #include "wx/log.h"
+    #include "wx/thread.h"
+    #include "wx/intl.h"
+    #include "wx/module.h"

 #endif
 
 #endif
 

-#include "wx/module.h"
+#include "wx/init.h"

 
 

-// ----------------------------------------------------------------------------
-// global vars
-// ----------------------------------------------------------------------------
+#include "wx/ptr_scpd.h"
+#include "wx/except.h"

 
 

-wxApp * WXDLLEXPORT wxTheApp = NULL;
+#if defined(__WXMSW__) && defined(__WXDEBUG__)
+    #include "wx/msw/msvcrt.h"

 
 

-wxAppInitializerFunction
-    wxAppBase::m_appInitFn = (wxAppInitializerFunction)NULL;
+    static struct EnableMemLeakChecking
+    {
+        EnableMemLeakChecking()
+        {
+            // do check for memory leaks on program exit (another useful flag
+            // is _CRTDBG_DELAY_FREE_MEM_DF which doesn't free deallocated
+            // memory which may be used to simulate low-memory condition)
+            wxCrtSetDbgFlag(_CRTDBG_LEAK_CHECK_DF);
+        }
+    } gs_enableLeakChecks;
+#endif // __WXMSW__ && __WXDEBUG__

 
 // ----------------------------------------------------------------------------
 // private classes
 // ----------------------------------------------------------------------------
 
 
 // ----------------------------------------------------------------------------
 // private classes
 // ----------------------------------------------------------------------------
 

-class /* no WXDLLEXPORT */ wxConsoleApp : public wxApp
+// we need a dummy app object if the user doesn't want to create a real one
+class wxDummyConsoleApp : public wxAppConsole

 {
 public:
 {
 public:

-    virtual int OnRun() { wxFAIL_MSG(wxT("unreachable")); return 0; }
+    wxDummyConsoleApp() { }
+
+    virtual int OnRun() { wxFAIL_MSG( _T("unreachable code") ); return 0; }
+
+    DECLARE_NO_COPY_CLASS(wxDummyConsoleApp)

 };
 
 };
 

+// we need a special kind of auto pointer to wxApp which not only deletes the
+// pointer it holds in its dtor but also resets the global application pointer
+wxDECLARE_SCOPED_PTR(wxAppConsole, wxAppPtrBase)
+wxDEFINE_SCOPED_PTR(wxAppConsole, wxAppPtrBase)
+
+class wxAppPtr : public wxAppPtrBase
+{
+public:
+    wxEXPLICIT wxAppPtr(wxAppConsole *ptr = NULL) : wxAppPtrBase(ptr) { }
+    ~wxAppPtr()
+    {
+        if ( get() )
+        {
+            // the pointer is going to be deleted in the base class dtor, don't
+            // leave the dangling pointer!
+            wxApp::SetInstance(NULL);
+        }
+    }
+
+    void Set(wxAppConsole *ptr)
+    {
+        reset(ptr);
+
+        wxApp::SetInstance(ptr);
+    }
+
+    DECLARE_NO_COPY_CLASS(wxAppPtr)
+};
+
+// class to ensure that wxAppBase::CleanUp() is called if our Initialize()
+// fails
+class wxCallAppCleanup
+{
+public:
+    wxCallAppCleanup(wxAppConsole *app) : m_app(app) { }
+    ~wxCallAppCleanup() { if ( m_app ) m_app->CleanUp(); }
+
+    void Dismiss() { m_app = NULL; }
+
+private:
+    wxAppConsole *m_app;
+};
+
+// another tiny class which simply exists to ensure that wxEntryCleanup is
+// always called
+class wxCleanupOnExit
+{
+public:
+    ~wxCleanupOnExit() { wxEntryCleanup(); }
+};
+
+// ----------------------------------------------------------------------------
+// private functions

 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------

-// private vars
+
+// suppress warnings about unused variables
+static inline void Use(void *) { }
+
+#define WX_SUPPRESS_UNUSED_WARN(x) Use(&x)
+

 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------

+// initialization data
+// ----------------------------------------------------------------------------
+
+static struct InitData
+{
+    InitData()
+    {
+        nInitCount = 0;
+
+#if wxUSE_UNICODE
+        argc = 0;
+        // argv = NULL; -- not even really needed
+#endif // wxUSE_UNICODE
+    }

 
 

-static size_t gs_nInitCount = 0;
+    // critical section protecting this struct
+    wxCRIT_SECT_DECLARE_MEMBER(csInit);
+
+    // number of times wxInitialize() was called minus the number of times
+    // wxUninitialize() was
+    size_t nInitCount;
+
+#if wxUSE_UNICODE
+    int argc;
+
+    // if we receive the command line arguments as ASCII and have to convert
+    // them to Unicode ourselves (this is the case under Unix but not Windows,
+    // for example), we remember the converted argv here because we'll have to
+    // free it when doing cleanup to avoid memory leaks
+    wchar_t **argv;
+#endif // wxUSE_UNICODE
+
+    DECLARE_NO_COPY_CLASS(InitData)
+} gs_initData;

 
 // ============================================================================
 // implementation
 // ============================================================================
 
 // ----------------------------------------------------------------------------
 
 // ============================================================================
 // implementation
 // ============================================================================
 
 // ----------------------------------------------------------------------------

-// stubs for some GUI functions
+// command line arguments ANSI -> Unicode conversion
+// ----------------------------------------------------------------------------
+
+#if wxUSE_UNICODE
+
+static void ConvertArgsToUnicode(int argc, char **argv)
+{
+    gs_initData.argv = new wchar_t *[argc + 1];
+    int wargc = 0;
+    for ( int i = 0; i < argc; i++ )
+    {
+        wxWCharBuffer buf(wxConvLocal.cMB2WX(argv[i]));
+        if ( !buf )
+        {
+            wxLogWarning(_("Command line argument %d couldn't be converted to Unicode and will be ignored."),
+                         i);
+        }
+        else // converted ok
+        {
+            gs_initData.argv[wargc++] = wxStrdup(buf);
+        }
+    }
+
+    gs_initData.argc = wargc;
+    gs_initData.argv[wargc] = NULL;
+}
+
+static void FreeConvertedArgs()
+{
+    if ( gs_initData.argv )
+    {
+        for ( int i = 0; i < gs_initData.argc; i++ )
+        {
+            free(gs_initData.argv[i]);
+        }
+
+        delete [] gs_initData.argv;
+        gs_initData.argv = NULL;
+        gs_initData.argc = 0;
+    }
+}
+
+#endif // wxUSE_UNICODE
+
+// ----------------------------------------------------------------------------
+// start up

 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 

-void WXDLLEXPORT wxExit()
+// initialization which is always done (not customizable) before wxApp creation
+static bool DoCommonPreInit()

 {
 {

-    abort();
+#if wxUSE_LOG
+    // install temporary log sink: we can't use wxLogGui before wxApp is
+    // constructed and if we use wxLogStderr, all messages during
+    // initialization simply disappear under Windows
+    //
+    // note that we will delete this log target below
+    delete wxLog::SetActiveTarget(new wxLogBuffer);
+#endif // wxUSE_LOG
+
+    return true;
+}
+
+// non customizable initialization done after wxApp creation and initialization
+static bool DoCommonPostInit()
+{
+    wxModule::RegisterModules();
+
+    if ( !wxModule::InitializeModules() )
+    {
+        wxLogError(_("Initialization failed in post init, aborting."));
+        return false;
+    }
+
+    return true;

 }
 
 }
 

-// Yield to other apps/messages
-bool WXDLLEXPORT wxYield()
+bool wxEntryStart(int& argc, wxChar **argv)

 {
 {

-    // do nothing
-    return TRUE;
+    // do minimal, always necessary, initialization
+    // --------------------------------------------
+
+    // initialize wxRTTI
+    if ( !DoCommonPreInit() )
+    {
+        return false;
+    }
+
+
+    // first of all, we need an application object
+    // -------------------------------------------
+
+    // the user might have already created it himself somehow
+    wxAppPtr app(wxTheApp);
+    if ( !app.get() )
+    {
+        // if not, he might have used IMPLEMENT_APP() to give us a function to
+        // create it
+        wxAppInitializerFunction fnCreate = wxApp::GetInitializerFunction();
+
+        if ( fnCreate )
+        {
+            // he did, try to create the custom wxApp object
+            app.Set((*fnCreate)());
+        }
+    }
+
+    if ( !app.get() )
+    {
+        // either IMPLEMENT_APP() was not used at all or it failed -- in any
+        // case we still need something
+        app.Set(new wxDummyConsoleApp);
+    }
+
+
+    // wxApp initialization: this can be customized
+    // --------------------------------------------
+
+    if ( !app->Initialize(argc, argv) )
+    {
+        return false;
+    }
+
+    wxCallAppCleanup callAppCleanup(app.get());
+
+    // for compatibility call the old initialization function too
+    if ( !app->OnInitGui() )
+        return false;
+
+
+    // common initialization after wxTheApp creation
+    // ---------------------------------------------
+
+    if ( !DoCommonPostInit() )
+        return false;
+
+
+    // prevent the smart pointer from destroying its contents
+    app.release();
+
+    // and the cleanup object from doing cleanup
+    callAppCleanup.Dismiss();
+
+#if wxUSE_LOG
+    // now that we have a valid wxApp (wxLogGui would have crashed if we used
+    // it before now), we can delete the temporary sink we had created for the
+    // initialization messages -- the next time logging function is called, the
+    // sink will be recreated but this time wxAppTraits will be used
+    delete wxLog::SetActiveTarget(NULL);
+#endif // wxUSE_LOG
+
+    return true;

 }
 
 }
 

-// Yield to other apps/messages
-void WXDLLEXPORT wxWakeUpIdle()
+#if wxUSE_UNICODE
+
+// we provide a wxEntryStart() wrapper taking "char *" pointer too
+bool wxEntryStart(int& argc, char **argv)

 {
 {

-    // do nothing
+    ConvertArgsToUnicode(argc, argv);
+
+    if ( !wxEntryStart(gs_initData.argc, gs_initData.argv) )
+    {
+        FreeConvertedArgs();
+
+        return false;
+    }
+
+    return true;

 }
 
 }
 

+#endif // wxUSE_UNICODE
+

 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------

-// wxBase-specific functions
+// clean up

 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 

-bool WXDLLEXPORT wxInitialize()
+// cleanup done before destroying wxTheApp
+static void DoCommonPreCleanup()
+{
+#if wxUSE_LOG
+    // flush the logged messages if any and install a 'safer' log target: the
+    // default one (wxLogGui) can't be used after the resources are freed just
+    // below and the user supplied one might be even more unsafe (using any
+    // wxWidgets GUI function is unsafe starting from now)
+    wxLog::DontCreateOnDemand();
+
+    // this will flush the old messages if any
+    delete wxLog::SetActiveTarget(new wxLogStderr);
+#endif // wxUSE_LOG
+}
+
+// cleanup done after destroying wxTheApp
+static void DoCommonPostCleanup()

 {
 {

-    if ( gs_nInitCount )
+    wxModule::CleanUpModules();
+
+    // we can't do this in wxApp itself because it doesn't know if argv had
+    // been allocated
+#if wxUSE_UNICODE
+    FreeConvertedArgs();
+#endif // wxUSE_UNICODE
+
+    // use Set(NULL) and not Get() to avoid creating a message output object on
+    // demand when we just want to delete it
+    delete wxMessageOutput::Set(NULL);
+
+#if wxUSE_LOG
+    // and now delete the last logger as well
+    delete wxLog::SetActiveTarget(NULL);
+#endif // wxUSE_LOG
+}
+
+void wxEntryCleanup()
+{
+    DoCommonPreCleanup();
+
+
+    // delete the application object
+    if ( wxTheApp )

     {
     {

-        // already initialized
-        return TRUE;
+        wxTheApp->CleanUp();
+
+        delete wxTheApp;
+        wxApp::SetInstance(NULL);

     }
 
     }
 

-    wxASSERT_MSG( !wxTheApp,
-                  wxT("either call wxInitialize or create app, not both!") );

 
 

-    wxClassInfo::InitializeClasses();
+    DoCommonPostCleanup();
+}

 
 

-    wxModule::RegisterModules();
-    if ( !wxModule::InitializeModules() )
+// ----------------------------------------------------------------------------
+// wxEntry
+// ----------------------------------------------------------------------------
+
+// for MSW the real wxEntry is defined in msw/main.cpp
+#ifndef __WXMSW__
+    #define wxEntryReal wxEntry
+#endif // !__WXMSW__
+
+int wxEntryReal(int& argc, wxChar **argv)
+{
+    // library initialization
+    if ( !wxEntryStart(argc, argv) )

     {
     {

-        return FALSE;
+#if wxUSE_LOG
+        // flush any log messages explaining why we failed
+        delete wxLog::SetActiveTarget(NULL);
+#endif
+        return -1;

     }
 
     }
 

-    wxTheApp = new wxConsoleApp;
+    // if wxEntryStart succeeded, we must call wxEntryCleanup even if the code
+    // below returns or throws
+    wxCleanupOnExit cleanupOnExit;

 
 

-    if ( !wxTheApp )
+    WX_SUPPRESS_UNUSED_WARN(cleanupOnExit);
+
+    wxTRY

     {
     {

-        return FALSE;
+
+        // app initialization
+        if ( !wxTheApp->CallOnInit() )
+        {
+            // don't call OnExit() if OnInit() failed
+            return -1;
+        }
+
+        // ensure that OnExit() is called if OnInit() had succeeded
+        class CallOnExit
+        {
+        public:
+            ~CallOnExit() { wxTheApp->OnExit(); }
+        } callOnExit;
+
+        WX_SUPPRESS_UNUSED_WARN(callOnExit);
+
+        // app execution
+        return wxTheApp->OnRun();

     }
     }

+    wxCATCH_ALL( wxTheApp->OnUnhandledException(); return -1; )
+}

 
 

-    gs_nInitCount++;
+#if wxUSE_UNICODE

 
 

-    return TRUE;
+// as with wxEntryStart, we provide an ANSI wrapper
+int wxEntry(int& argc, char **argv)
+{
+    ConvertArgsToUnicode(argc, argv);
+
+    return wxEntry(gs_initData.argc, gs_initData.argv);

 }
 
 }
 

-void WXDLLEXPORT wxUninitialize()
+#endif // wxUSE_UNICODE
+
+// ----------------------------------------------------------------------------
+// wxInitialize/wxUninitialize
+// ----------------------------------------------------------------------------
+
+bool wxInitialize(int argc, wxChar **argv)

 {
 {

-    if ( !--gs_nInitCount )
+    wxCRIT_SECT_LOCKER(lockInit, gs_initData.csInit);
+
+    if ( gs_initData.nInitCount++ )

     {
     {

-        wxModule::CleanUpModules();
+        // already initialized
+        return true;
+    }

 
 

-        wxClassInfo::CleanUpClasses();
+    return wxEntryStart(argc, argv);
+}

 
 

-        // delete the application object
-        delete wxTheApp;
-        wxTheApp = (wxApp *)NULL;
+void wxUninitialize()
+{
+    wxCRIT_SECT_LOCKER(lockInit, gs_initData.csInit);
+
+    if ( --gs_initData.nInitCount == 0 )
+    {
+        wxEntryCleanup();

     }
 }
     }
 }