]> git.saurik.com Git - wxWidgets.git/blobdiff - src/gtk/clipbrd.cpp
projects / wxWidgets.git / blobdiff
? search:
summary | shortlog | log | commit | commitdiff | tree
raw | inline | side by side
guarding scrollbar
[wxWidgets.git] / src / gtk / clipbrd.cpp
diff --git a/src/gtk/clipbrd.cpp b/src/gtk/clipbrd.cpp
index d029dd027c02985230eed00c515133aaa83aabf7..538a80e7af18d42b5a155efd4a8afef8d56c42e8 100644 (file)
--- a/src/gtk/clipbrd.cpp
+++ b/src/gtk/clipbrd.cpp
@@ -1,364 +1,728 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////
-// Name:        clipbrd.cpp
-// Purpose:
-// Author:      Robert Roebling
+// Name:        src/gtk/clipbrd.cpp
+// Purpose:     wxClipboard implementation for wxGTK
+// Author:      Robert Roebling, Vadim Zeitlin
 // Id:          $Id$
 // Copyright:   (c) 1998 Robert Roebling
 // Id:          $Id$
 // Copyright:   (c) 1998 Robert Roebling
-// Licence:    wxWindows licence
+//              (c) 2007 Vadim Zeitlin
+// Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 /////////////////////////////////////////////////////////////////////////////
 
-#ifdef __GNUG__
-#pragma implementation "clipbrd.h"
-#endif
+// ============================================================================
+// declarations
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------
+
+// For compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#if wxUSE_CLIPBOARD
 
 #include "wx/clipbrd.h"
 
 
 #include "wx/clipbrd.h"
 
-//-----------------------------------------------------------------------------
-// data
-//-----------------------------------------------------------------------------
+#ifndef WX_PRECOMP
+    #include "wx/app.h"
+    #include "wx/log.h"
+    #include "wx/utils.h"
+    #include "wx/dataobj.h"
+#endif
 
 
-wxClipboard *wxTheClipboard = (wxClipboard*) NULL;
+#include "wx/scopedarray.h"
+#include "wx/scopeguard.h"
+#include "wx/evtloop.h"
 
 
-GdkAtom  g_textAtom        = 0;
-GdkAtom  g_clipboardAtom   = 0;
-GdkAtom  g_targetsAtom     = 0;
+#include "wx/gtk/private.h"
 
 
-//-----------------------------------------------------------------------------
-// reminder
-//-----------------------------------------------------------------------------
+typedef wxScopedArray<wxDataFormat> wxDataFormatArray;
+
+// ----------------------------------------------------------------------------
+// data
+// ----------------------------------------------------------------------------
 
 
-/* The contents of a selection are returned in a GtkSelectionData
-   structure. selection/target identify the request. 
-   type specifies the type of the return; if length < 0, and
-   the data should be ignored. This structure has object semantics -
-   no fields should be modified directly, they should not be created
-   directly, and pointers to them should not be stored beyond the duration of
-   a callback. (If the last is changed, we'll need to add reference
-   counting)
+static GdkAtom  g_clipboardAtom   = 0;
+static GdkAtom  g_targetsAtom     = 0;
+static GdkAtom  g_timestampAtom   = 0;
 
 
-struct _GtkSelectionData
+#if wxUSE_UNICODE
+extern GdkAtom g_altTextAtom;
+#endif
+
+// the trace mask we use with wxLogTrace() - call
+// wxLog::AddTraceMask(TRACE_CLIPBOARD) to enable the trace messages from here
+// (there will be a *lot* of them!)
+#define TRACE_CLIPBOARD _T("clipboard")
+
+// ----------------------------------------------------------------------------
+// wxClipboardSync: used to perform clipboard operations synchronously
+// ----------------------------------------------------------------------------
+
+// constructing this object on stack will wait wait until the latest clipboard
+// operation is finished on block exit
+//
+// notice that there can be no more than one such object alive at any moment,
+// i.e. reentrancies are not allowed
+class wxClipboardSync
 {
 {
-  GdkAtom selection;
-  GdkAtom target;
-  GdkAtom type;
-  gint   format;
-  guchar *data;
-  gint   length;
+public:
+    wxClipboardSync(wxClipboard& clipboard)
+    {
+        wxASSERT_MSG( !ms_clipboard, _T("reentrancy in clipboard code") );
+        ms_clipboard = &clipboard;
+    }
+
+    ~wxClipboardSync()
+    {
+        while (ms_clipboard)
+            wxEventLoopBase::GetActive()->YieldFor(wxEVT_CATEGORY_CLIPBOARD);
+    }
+
+    // this method must be called by GTK+ callbacks to indicate that we got the
+    // result for our clipboard operation
+    static void OnDone(wxClipboard * WXUNUSED_UNLESS_DEBUG(clipboard))
+    {
+        wxASSERT_MSG( clipboard == ms_clipboard,
+                        _T("got notification for alien clipboard") );
+
+        ms_clipboard = NULL;
+    }
+
+    // this method should be called if it's possible that no async clipboard
+    // operation is currently in progress (like it can be the case when the
+    // clipboard is cleared but not because we asked about it), it should only
+    // be called if such situation is expected -- otherwise call OnDone() which
+    // would assert in this case
+    static void OnDoneIfInProgress(wxClipboard *clipboard)
+    {
+        if ( ms_clipboard )
+            OnDone(clipboard);
+    }
+
+private:
+    static wxClipboard *ms_clipboard;
+
+    wxDECLARE_NO_COPY_CLASS(wxClipboardSync);
 };
 
 };
 
-*/
+wxClipboard *wxClipboardSync::ms_clipboard = NULL;
+
+// ============================================================================
+// clipboard callbacks implementation
+// ============================================================================
 
 //-----------------------------------------------------------------------------
 // "selection_received" for targets
 //-----------------------------------------------------------------------------
 
 
 //-----------------------------------------------------------------------------
 // "selection_received" for targets
 //-----------------------------------------------------------------------------
 
+extern "C" {
 static void
 static void
-targets_selection_received( GtkWidget *WXUNUSED(widget), 
-                            GtkSelectionData *selection_data, 
-                           wxClipboard *clipboard )
+targets_selection_received( GtkWidget *WXUNUSED(widget),
+                            GtkSelectionData *selection_data,
+                            guint32 WXUNUSED(time),
+                            wxClipboard *clipboard )
 {
 {
-  if (!wxTheClipboard) return;
-  
-  if (selection_data->length <= 0) return;
-  
-  // make sure we got the data in the correct form 
-  if (selection_data->type != GDK_SELECTION_TYPE_ATOM) return;
-  
-  // the atoms we received, holding a list of targets (= formats) 
-  GdkAtom *atoms = (GdkAtom *)selection_data->data;
-
-  for (unsigned int i=0; i<selection_data->length/sizeof(GdkAtom); i++)
-  {
-     if (atoms[i] == clipboard->m_targetRequested)
-     {
-       clipboard->m_formatSupported = TRUE;
-       return;
-     }
-  }
-
-  return;
+    if ( !clipboard )
+        return;
+
+    wxON_BLOCK_EXIT1(wxClipboardSync::OnDone, clipboard);
+
+    if ( !selection_data || selection_data->length <= 0 )
+        return;
+
+    // make sure we got the data in the correct form
+    GdkAtom type = selection_data->type;
+    if ( type != GDK_SELECTION_TYPE_ATOM )
+    {
+        if ( strcmp(wxGtkString(gdk_atom_name(type)), "TARGETS") != 0 )
+        {
+            wxLogTrace( TRACE_CLIPBOARD,
+                        _T("got unsupported clipboard target") );
+
+            return;
+        }
+    }
+
+    // it's not really a format, of course, but we can reuse its GetId() method
+    // to format this atom as string
+    wxDataFormat clip(selection_data->selection);
+    wxLogTrace( TRACE_CLIPBOARD,
+                wxT("Received available formats for clipboard %s"),
+                clip.GetId().c_str() );
+
+    // the atoms we received, holding a list of targets (= formats)
+    const GdkAtom * const atoms = (GdkAtom *)selection_data->data;
+    for ( size_t i = 0; i < selection_data->length/sizeof(GdkAtom); i++ )
+    {
+        const wxDataFormat format(atoms[i]);
+
+        wxLogTrace(TRACE_CLIPBOARD, wxT("\t%s"), format.GetId().c_str());
+
+        if ( clipboard->GTKOnTargetReceived(format) )
+            return;
+    }
+}
+}
+
+bool wxClipboard::GTKOnTargetReceived(const wxDataFormat& format)
+{
+    if ( format != m_targetRequested )
+        return false;
+
+    m_formatSupported = true;
+    return true;
 }
 
 //-----------------------------------------------------------------------------
 // "selection_received" for the actual data
 //-----------------------------------------------------------------------------
 
 }
 
 //-----------------------------------------------------------------------------
 // "selection_received" for the actual data
 //-----------------------------------------------------------------------------
 
-static void 
-selection_received( GtkWidget *WXUNUSED(widget), 
-                    GtkSelectionData *selection_data, 
-                   wxClipboard *clipboard )
+extern "C" {
+static void
+selection_received( GtkWidget *WXUNUSED(widget),
+                    GtkSelectionData *selection_data,
+                    guint32 WXUNUSED(time),
+                    wxClipboard *clipboard )
 {
 {
-  if (!wxTheClipboard) return;
-  
-  if (selection_data->length <= 0) return;
-  
-  size_t size = (size_t) selection_data->length;
-  
-  // make sure we got the data in the correct form 
-  if (selection_data->type != GDK_SELECTION_TYPE_STRING) return;
-  
-  clipboard->m_receivedSize = size;
-  
-  clipboard->m_receivedData = new char[size+1];
-  
-  memcpy( clipboard->m_receivedData, selection_data->data, size);  
+    if ( !clipboard )
+        return;
+
+    wxON_BLOCK_EXIT1(wxClipboardSync::OnDone, clipboard);
+
+    if ( !selection_data || selection_data->length <= 0 )
+        return;
+
+    clipboard->GTKOnSelectionReceived(*selection_data);
+}
 }
 
 //-----------------------------------------------------------------------------
 // "selection_clear"
 //-----------------------------------------------------------------------------
 
 }
 
 //-----------------------------------------------------------------------------
 // "selection_clear"
 //-----------------------------------------------------------------------------
 
+extern "C" {
 static gint
 static gint
-selection_clear( GtkWidget *WXUNUSED(widget), GdkEventSelection *WXUNUSED(event) )
+selection_clear_clip( GtkWidget *WXUNUSED(widget), GdkEventSelection *event )
 {
 {
-  if (!wxTheClipboard) return TRUE;
-  
-  /* the clipboard is no longer in our hands. we can delete the
-   * clipboard data. I hope I got that one right... */
-    
-  wxTheClipboard->SetData( (wxDataObject*) NULL );
-  
-  return TRUE;
+    wxClipboard * const clipboard = wxTheClipboard;
+    if ( !clipboard )
+        return TRUE;
+
+    // notice the use of OnDoneIfInProgress() here instead of just OnDone():
+    // it's perfectly possible that we're receiving this notification from GTK+
+    // even though we hadn't cleared the clipboard ourselves but because
+    // another application (or even another window in the same program)
+    // acquired it
+    wxON_BLOCK_EXIT1(wxClipboardSync::OnDoneIfInProgress, clipboard);
+
+    wxClipboard::Kind kind;
+    if (event->selection == GDK_SELECTION_PRIMARY)
+    {
+        wxLogTrace(TRACE_CLIPBOARD, wxT("Lost primary selection" ));
+
+        kind = wxClipboard::Primary;
+    }
+    else if (event->selection == g_clipboardAtom)
+    {
+        wxLogTrace(TRACE_CLIPBOARD, wxT("Lost clipboard" ));
+
+        kind = wxClipboard::Clipboard;
+    }
+    else // some other selection, we're not concerned
+    {
+        return FALSE;
+    }
+
+    // the clipboard is no longer in our hands, we don't need data any more
+    clipboard->GTKClearData(kind);
+
+    return TRUE;
+}
 }
 
 //-----------------------------------------------------------------------------
 // selection handler for supplying data
 //-----------------------------------------------------------------------------
 
 }
 
 //-----------------------------------------------------------------------------
 // selection handler for supplying data
 //-----------------------------------------------------------------------------
 
+extern "C" {
 static void
 static void
-selection_handler( GtkWidget *WXUNUSED(widget), GtkSelectionData *selection_data, gpointer WXUNUSED(data) )
+selection_handler( GtkWidget *WXUNUSED(widget),
+                   GtkSelectionData *selection_data,
+                   guint WXUNUSED(info),
+                   guint WXUNUSED(time),
+                   gpointer signal_data )
+{
+    wxClipboard * const clipboard = wxTheClipboard;
+    if ( !clipboard )
+        return;
+
+    wxDataObject * const data = clipboard->GTKGetDataObject();
+    if ( !data )
+        return;
+
+    // ICCCM says that TIMESTAMP is a required atom.
+    // In particular, it satisfies Klipper, which polls
+    // TIMESTAMP to see if the clipboards content has changed.
+    // It shall return the time which was used to set the data.
+    if (selection_data->target == g_timestampAtom)
+    {
+        guint timestamp = GPOINTER_TO_UINT (signal_data);
+        gtk_selection_data_set(selection_data,
+                               GDK_SELECTION_TYPE_INTEGER,
+                               32,
+                               (guchar*)&(timestamp),
+                               sizeof(timestamp));
+        wxLogTrace(TRACE_CLIPBOARD,
+                   _T("Clipboard TIMESTAMP requested, returning timestamp=%u"),
+                   timestamp);
+        return;
+    }
+
+    wxDataFormat format( selection_data->target );
+
+    wxLogTrace(TRACE_CLIPBOARD,
+               _T("clipboard data in format %s, GtkSelectionData is target=%s type=%s selection=%s timestamp=%u"),
+               format.GetId().c_str(),
+               wxString::FromAscii(wxGtkString(gdk_atom_name(selection_data->target))).c_str(),
+               wxString::FromAscii(wxGtkString(gdk_atom_name(selection_data->type))).c_str(),
+               wxString::FromAscii(wxGtkString(gdk_atom_name(selection_data->selection))).c_str(),
+               GPOINTER_TO_UINT( signal_data )
+               );
+
+    if ( !data->IsSupportedFormat( format ) )
+        return;
+
+    int size = data->GetDataSize( format );
+    if ( !size )
+        return;
+
+    wxCharBuffer buf(size - 1); // it adds 1 internally (for NUL)
+
+    // text data must be returned in UTF8 if format is wxDF_UNICODETEXT
+    if ( !data->GetDataHere(format, buf.data()) )
+        return;
+
+    // use UTF8_STRING format if requested in Unicode build but just plain
+    // STRING one in ANSI or if explicitly asked in Unicode
+#if wxUSE_UNICODE
+    if (format == wxDataFormat(wxDF_UNICODETEXT))
+    {
+        gtk_selection_data_set_text(
+            selection_data,
+            (const gchar*)buf.data(),
+            size );
+    }
+    else
+#endif // wxUSE_UNICODE
+    {
+        gtk_selection_data_set(
+            selection_data,
+            GDK_SELECTION_TYPE_STRING,
+            8*sizeof(gchar),
+            (const guchar*)buf.data(),
+            size );
+    }
+}
+}
+
+void wxClipboard::GTKOnSelectionReceived(const GtkSelectionData& sel)
 {
 {
-  if (!wxTheClipboard) return;
-  
-  wxDataObject *data_object = wxTheClipboard->m_data;
-  
-  if (!data_object) return;
-  
-  if (data_object->GetDataSize() == 0) return;
-
-  
-  
-  gint len = data_object->GetDataSize();
-  guchar *bin_data = (guchar*) malloc( len );
-  data_object->GetDataHere( (void*)bin_data );
-  
-  if (selection_data->target == GDK_TARGET_STRING)
-  {
-    gtk_selection_data_set( 
-      selection_data, GDK_SELECTION_TYPE_STRING, 8*sizeof(gchar), bin_data, len );
-  }
-/*
-  else if (selection_data->target == g_textAtom)
-  {
-    gtk_selection_data_set( 
-      selection_data, g_textAtom, 8*sizeof(gchar), bin_data, len );
-  }
-*/
-  free( bin_data );
+    wxCHECK_RET( m_receivedData, _T("should be inside GetData()") );
+
+    const wxDataFormat format(sel.target);
+    wxLogTrace(TRACE_CLIPBOARD, _T("Received selection %s"),
+               format.GetId().c_str());
+
+    if ( !m_receivedData->IsSupportedFormat(format) )
+        return;
+
+    m_receivedData->SetData(format, sel.length, sel.data);
+    m_formatSupported = true;
 }
 
 //-----------------------------------------------------------------------------
 }
 
 //-----------------------------------------------------------------------------
-// wxClipboard
+// asynchronous "selection_received" for targets
 //-----------------------------------------------------------------------------
 
 //-----------------------------------------------------------------------------
 
+extern "C" {
+static void
+async_targets_selection_received( GtkWidget *WXUNUSED(widget),
+                            GtkSelectionData *selection_data,
+                            guint32 WXUNUSED(time),
+                            wxClipboard *clipboard )
+{
+    if ( !clipboard ) // Assert?
+        return;
+
+    if (!clipboard->m_sink)
+        return;
+
+    wxClipboardEvent *event = new wxClipboardEvent(wxEVT_CLIPBOARD_CHANGED);
+    event->SetEventObject( clipboard );
+
+    if ( !selection_data || selection_data->length <= 0 )
+    {
+        clipboard->m_sink->QueueEvent( event );
+        clipboard->m_sink.Release();
+        return;
+    }
+
+    // make sure we got the data in the correct form
+    GdkAtom type = selection_data->type;
+    if ( type != GDK_SELECTION_TYPE_ATOM )
+    {
+        if ( strcmp(wxGtkString(gdk_atom_name(type)), "TARGETS") != 0 )
+        {
+            wxLogTrace( TRACE_CLIPBOARD,
+                        _T("got unsupported clipboard target") );
+
+            clipboard->m_sink->QueueEvent( event );
+            clipboard->m_sink.Release();
+            return;
+        }
+    }
+
+    // it's not really a format, of course, but we can reuse its GetId() method
+    // to format this atom as string
+    wxDataFormat clip(selection_data->selection);
+    wxLogTrace( TRACE_CLIPBOARD,
+                wxT("Received available formats for clipboard %s"),
+                clip.GetId().c_str() );
+
+    // the atoms we received, holding a list of targets (= formats)
+    const GdkAtom * const atoms = (GdkAtom *)selection_data->data;
+    for ( size_t i = 0; i < selection_data->length/sizeof(GdkAtom); i++ )
+    {
+        const wxDataFormat format(atoms[i]);
+
+        wxLogTrace(TRACE_CLIPBOARD, wxT("\t%s"), format.GetId().c_str());
+
+        event->AddFormat( format );
+    }
+
+    clipboard->m_sink->QueueEvent( event );
+    clipboard->m_sink.Release();
+}
+}
+
+// ============================================================================
+// wxClipboard implementation
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// wxClipboard ctor/dtor
+// ----------------------------------------------------------------------------
+
 IMPLEMENT_DYNAMIC_CLASS(wxClipboard,wxObject)
 
 wxClipboard::wxClipboard()
 {
 IMPLEMENT_DYNAMIC_CLASS(wxClipboard,wxObject)
 
 wxClipboard::wxClipboard()
 {
-  m_data = (wxDataObject*) NULL;
-  
-  gtk_signal_connect( GTK_OBJECT(m_clipboardWidget), 
-                      "selection_clear_event",
-                     GTK_SIGNAL_FUNC( selection_clear ), 
-                     (gpointer) NULL );
-                     
-  if (!g_clipboardAtom) g_clipboardAtom = gdk_atom_intern( "CLIPBOARD", FALSE );
-  if (!g_textAtom) g_textAtom = gdk_atom_intern( "TEXT", FALSE );
-  if (!g_targetsAtom) g_targetsAtom = gdk_atom_intern ("TARGETS", FALSE);
-  
-  m_receivedData = (char*)NULL;
-  m_receivedSize = 0;
-  m_formatSupported = FALSE;
-  m_targetRequested = 0;
+    m_open = false;
+
+    m_dataPrimary =
+    m_dataClipboard =
+    m_receivedData = NULL;
+
+    m_formatSupported = false;
+    m_targetRequested = 0;
+
+    // we use m_targetsWidget to query what formats are available
+    m_targetsWidget = gtk_window_new( GTK_WINDOW_POPUP );
+    gtk_widget_realize( m_targetsWidget );
+
+    g_signal_connect (m_targetsWidget, "selection_received",
+                      G_CALLBACK (targets_selection_received), this);
+
+    // we use m_targetsWidgetAsync to query what formats are available asynchronously
+    m_targetsWidgetAsync = gtk_window_new( GTK_WINDOW_POPUP );
+    gtk_widget_realize( m_targetsWidgetAsync );
+
+    g_signal_connect (m_targetsWidgetAsync, "selection_received",
+                      G_CALLBACK (async_targets_selection_received), this);
+
+    // we use m_clipboardWidget to get and to offer data
+    m_clipboardWidget = gtk_window_new( GTK_WINDOW_POPUP );
+    gtk_widget_realize( m_clipboardWidget );
+
+    g_signal_connect (m_clipboardWidget, "selection_received",
+                      G_CALLBACK (selection_received), this);
+
+    g_signal_connect (m_clipboardWidget, "selection_clear_event",
+                      G_CALLBACK (selection_clear_clip), NULL);
+
+    // initialize atoms we use if not done yet
+    if ( !g_clipboardAtom )
+        g_clipboardAtom = gdk_atom_intern( "CLIPBOARD", FALSE );
+    if ( !g_targetsAtom )
+        g_targetsAtom = gdk_atom_intern ("TARGETS", FALSE);
+    if ( !g_timestampAtom )
+        g_timestampAtom = gdk_atom_intern ("TIMESTAMP", FALSE);
 }
 
 wxClipboard::~wxClipboard()
 {
 }
 
 wxClipboard::~wxClipboard()
 {
-  Clear();  
-  
-  if (m_clipboardWidget) gtk_widget_destroy( m_clipboardWidget );
+    Clear();
+
+    gtk_widget_destroy( m_clipboardWidget );
+    gtk_widget_destroy( m_targetsWidget );
+}
+
+// ----------------------------------------------------------------------------
+// wxClipboard helper functions
+// ----------------------------------------------------------------------------
+
+GdkAtom wxClipboard::GTKGetClipboardAtom() const
+{
+    return m_usePrimary ? (GdkAtom)GDK_SELECTION_PRIMARY
+                        : g_clipboardAtom;
 }
 
 }
 
-void wxClipboard::Clear()
+void wxClipboard::GTKClearData(Kind kind)
 {
 {
-  /* As we have data we also own the clipboard. Once we no longer own
-     it, clear_selection is called which will set m_data to zero */
-     
-  if (m_data)
-  { 
-    if (gdk_selection_owner_get( g_clipboardAtom) == m_clipboardWidget->window)
+    wxDataObject *&data = Data(kind);
+    if ( data )
     {
     {
-        gtk_selection_owner_set( (GtkWidget*) NULL, g_clipboardAtom, GDK_CURRENT_TIME );
+        delete data;
+        data = NULL;
     }
     }
-    
-    delete m_data;
-    m_data = (wxDataObject*) NULL;
-  }
-  
-  m_receivedSize = 0;
-  
-  if (m_receivedData)
-  {
-    delete[] m_receivedData;
-    m_receivedData = (char*) NULL;
-  }
-  
-  m_targetRequested = 0;
-  
-  m_formatSupported = FALSE;
 }
 
 }
 
-void wxClipboard::SetData( wxDataObject *data )
+bool wxClipboard::SetSelectionOwner(bool set)
 {
 {
-  Clear();
-  
-/*
-   GTK 1.0.X cannot remove a target from a widget so if a widget
-   at first offers text and then a bitmap (and no longer text) to 
-   the clipboard, we seem too have to delete it.
-*/
-
-  if (m_clipboardWidget) gtk_widget_destroy( m_clipboardWidget );
-  
-  m_clipboardWidget = gtk_window_new( GTK_WINDOW_POPUP );
-  gtk_widget_realize( m_clipboardWidget );
-
-
-  if (m_data) delete m_data;
-  m_data = data;
-  if (!m_data) return;
- 
-  if (!gtk_selection_owner_set( m_clipboardWidget, 
-                                g_clipboardAtom,
-                               GDK_CURRENT_TIME))
-  {
-    delete m_data;
-    m_data = (wxDataObject*) NULL;
-    return;
-  }
-  
-  switch (m_data->GetPreferredFormat())
-  {
-    case wxDF_TEXT:
-      gtk_selection_add_handler( m_clipboardWidget, 
-                                 g_clipboardAtom, 
-                               // g_textAtom,
-                                GDK_TARGET_STRING,
-                                selection_handler,
-                                NULL );
-      break;
-    default:
-      break;
-  }
+    bool rc = gtk_selection_owner_set
+              (
+                set ? m_clipboardWidget : NULL,
+                GTKGetClipboardAtom(),
+                (guint32)GDK_CURRENT_TIME
+              );
+
+    if ( !rc )
+    {
+        wxLogTrace(TRACE_CLIPBOARD, _T("Failed to %sset selection owner"),
+                   set ? _T("") : _T("un"));
+    }
+
+    return rc;
 }
 
 }
 
-bool wxClipboard::IsSupportedFormat( wxDataFormat format )
+void wxClipboard::AddSupportedTarget(GdkAtom atom)
 {
 {
-  m_targetRequested = 0;
-  
-  if (format == wxDF_TEXT)
-  {
-//     m_targetRequested = g_textAtom;
-     m_targetRequested = GDK_TARGET_STRING;
-  }
-  
-  if (m_targetRequested == 0) return FALSE;
-
-  gtk_signal_connect( GTK_OBJECT(m_clipboardWidget), 
-                      "selection_received",
-                     GTK_SIGNAL_FUNC( targets_selection_received ), 
-                     (gpointer) this );
-  
-  m_formatSupported = FALSE;
-  
-  gtk_selection_convert( m_clipboardWidget,
-                        g_clipboardAtom, 
-                        g_targetsAtom,
-                        GDK_CURRENT_TIME );
-
-  gtk_signal_disconnect_by_func( GTK_OBJECT(m_clipboardWidget), 
-                                GTK_SIGNAL_FUNC( targets_selection_received ),
-                                (gpointer) this );
-  
-  if (!m_formatSupported) return FALSE;
-  
-  return TRUE;
+    gtk_selection_add_target
+    (
+        m_clipboardWidget,
+        GTKGetClipboardAtom(),
+        atom,
+        0 // info (same as client data) unused
+    );
 }
 
 }
 
-bool wxClipboard::ObtainData( wxDataFormat format )
+bool wxClipboard::IsSupportedAsync(wxEvtHandler *sink)
 {
 {
-  m_receivedSize = 0;
-  
-  if (m_receivedData)
-  {
-    delete[] m_receivedData;
-    m_receivedData = (char*) NULL;
-  }
-  
-  m_targetRequested = 0;
-  
-  if (format == wxDF_TEXT)
-  {
-//     m_targetRequested = g_textAtom;
-     m_targetRequested = GDK_TARGET_STRING;
-  }
-  
-  if (m_targetRequested == 0) return FALSE;
-
-  gtk_signal_connect( GTK_OBJECT(m_clipboardWidget), 
-                      "selection_received",
-                     GTK_SIGNAL_FUNC( selection_received ), 
-                     (gpointer) this );
-
-  gtk_selection_convert( m_clipboardWidget,
-                        g_clipboardAtom, 
-                        m_targetRequested,
-                        GDK_CURRENT_TIME );
-  
-  gtk_signal_disconnect_by_func( GTK_OBJECT(m_clipboardWidget), 
-                                GTK_SIGNAL_FUNC( selection_received ),
-                                (gpointer) this );
-    
-  if (m_receivedSize == 0) return FALSE;
-  
-  return TRUE;
+    if (m_sink.get())
+        return false;  // currently busy, come back later
+
+    wxCHECK_MSG( sink, false, wxT("no sink given") );
+
+    m_sink = sink;
+    gtk_selection_convert( m_targetsWidgetAsync,
+                           GTKGetClipboardAtom(),
+                           g_targetsAtom,
+                           (guint32) GDK_CURRENT_TIME );
+
+    return true;
 }
 
 }
 
-size_t wxClipboard::GetDataSize() const
+bool wxClipboard::DoIsSupported(const wxDataFormat& format)
 {
 {
-  return m_receivedSize;
+    wxCHECK_MSG( format, false, wxT("invalid clipboard format") );
+
+    wxLogTrace(TRACE_CLIPBOARD, wxT("Checking if format %s is available"),
+               format.GetId().c_str());
+
+    // these variables will be used by our GTKOnTargetReceived()
+    m_targetRequested = format;
+    m_formatSupported = false;
+
+    // block until m_formatSupported is set from targets_selection_received
+    // callback
+    {
+        wxClipboardSync sync(*this);
+
+        gtk_selection_convert( m_targetsWidget,
+                               GTKGetClipboardAtom(),
+                               g_targetsAtom,
+                               (guint32) GDK_CURRENT_TIME );
+    }
+
+    return m_formatSupported;
 }
 
 }
 
-void wxClipboard::GetDataHere( void *data ) const
+// ----------------------------------------------------------------------------
+// wxClipboard public API implementation
+// ----------------------------------------------------------------------------
+
+void wxClipboard::Clear()
 {
 {
-  memcpy(data, m_receivedData, m_receivedSize );
+    if ( gdk_selection_owner_get(GTKGetClipboardAtom()) ==
+            m_clipboardWidget->window )
+    {
+        wxClipboardSync sync(*this);
+
+        // this will result in selection_clear_clip callback being called and
+        // it will free our data
+        SetSelectionOwner(false);
+    }
+
+    m_targetRequested = 0;
+    m_formatSupported = false;
 }
 
 }
 
-//-----------------------------------------------------------------------------
-// wxClipboardModule
-//-----------------------------------------------------------------------------
+bool wxClipboard::Open()
+{
+    wxCHECK_MSG( !m_open, false, wxT("clipboard already open") );
+
+    m_open = true;
 
 
-IMPLEMENT_DYNAMIC_CLASS(wxClipboardModule,wxModule)
+    return true;
+}
 
 
-bool wxClipboardModule::OnInit()
+bool wxClipboard::SetData( wxDataObject *data )
 {
 {
-  wxTheClipboard = new wxClipboard();
-  
-  return TRUE;
+    wxCHECK_MSG( m_open, false, wxT("clipboard not open") );
+
+    wxCHECK_MSG( data, false, wxT("data is invalid") );
+
+    Clear();
+
+    return AddData( data );
 }
 
 }
 
-void wxClipboardModule::OnExit()
+bool wxClipboard::AddData( wxDataObject *data )
 {
 {
-  if (wxTheClipboard) delete wxTheClipboard;
-  wxTheClipboard = (wxClipboard*) NULL;
+    wxCHECK_MSG( m_open, false, wxT("clipboard not open") );
+
+    wxCHECK_MSG( data, false, wxT("data is invalid") );
+
+    // we can only store one wxDataObject so clear the old one
+    Clear();
+
+    Data() = data;
+
+    // get formats from wxDataObjects
+    const size_t count = data->GetFormatCount();
+    wxDataFormatArray formats(new wxDataFormat[count]);
+    data->GetAllFormats(formats.get());
+
+    // always provide TIMESTAMP as a target, see comments in selection_handler
+    // for explanation
+    AddSupportedTarget(g_timestampAtom);
+
+    for ( size_t i = 0; i < count; i++ )
+    {
+        const wxDataFormat format(formats[i]);
+
+        wxLogTrace(TRACE_CLIPBOARD, wxT("Adding support for %s"),
+                   format.GetId().c_str());
+
+        AddSupportedTarget(format);
+    }
+
+    g_signal_connect (m_clipboardWidget, "selection_get",
+                      G_CALLBACK (selection_handler),
+                      GUINT_TO_POINTER (gtk_get_current_event_time()) );
+
+    // tell the world we offer clipboard data
+    return SetSelectionOwner();
 }
 }
+
+void wxClipboard::Close()
+{
+    wxCHECK_RET( m_open, wxT("clipboard not open") );
+
+    m_open = false;
+}
+
+bool wxClipboard::IsOpened() const
+{
+    return m_open;
+}
+
+bool wxClipboard::IsSupported( const wxDataFormat& format )
+{
+    if ( DoIsSupported(format) )
+        return true;
+
+#if wxUSE_UNICODE
+    if ( format == wxDF_UNICODETEXT )
+    {
+        // also with plain STRING format
+        return DoIsSupported(g_altTextAtom);
+    }
+#endif // wxUSE_UNICODE
+
+    return false;
+}
+
+bool wxClipboard::GetData( wxDataObject& data )
+{
+    wxCHECK_MSG( m_open, false, wxT("clipboard not open") );
+
+    // get all supported formats from wxDataObjects
+    const size_t count = data.GetFormatCount();
+    wxDataFormatArray formats(new wxDataFormat[count]);
+    data.GetAllFormats(formats.get());
+
+    for ( size_t i = 0; i < count; i++ )
+    {
+        const wxDataFormat format(formats[i]);
+
+        // is this format supported by clipboard ?
+        if ( !DoIsSupported(format) )
+            continue;
+
+        wxLogTrace(TRACE_CLIPBOARD, wxT("Requesting format %s"),
+                   format.GetId().c_str());
+
+        // these variables will be used by our GTKOnSelectionReceived()
+        m_receivedData = &data;
+        m_formatSupported = false;
+
+        {
+            wxClipboardSync sync(*this);
+
+            gtk_selection_convert(m_clipboardWidget,
+                                  GTKGetClipboardAtom(),
+                                  format,
+                                  (guint32) GDK_CURRENT_TIME );
+        } // wait until we get the results
+
+        /*
+           Normally this is a true error as we checked for the presence of such
+           data before, but there are applications that may return an empty
+           string (e.g. Gnumeric-1.6.1 on Linux if an empty cell is copied)
+           which would produce a false error message here, so we check for the
+           size of the string first. With ANSI, GetDataSize returns an extra
+           value (for the closing null?), with unicode, the exact number of
+           tokens is given (that is more than 1 for non-ASCII characters)
+           (tested with Gnumeric-1.6.1 and OpenOffice.org-2.0.2)
+         */
+#if wxUSE_UNICODE
+        if ( format != wxDF_UNICODETEXT || data.GetDataSize(format) > 0 )
+#else // !UNICODE
+        if ( format != wxDF_TEXT || data.GetDataSize(format) > 1 )
+#endif // UNICODE / !UNICODE
+        {
+            wxCHECK_MSG( m_formatSupported, false,
+                         wxT("error retrieving data from clipboard") );
+        }
+
+        return true;
+    }
+
+    wxLogTrace(TRACE_CLIPBOARD, wxT("GetData(): format not found"));
+
+    return false;
+}
+
+#endif // wxUSE_CLIPBOARD
wxWidgets (Impactor)