src/gtk/clipbrd.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/gtk/clipbrd.cpp
   3 // Purpose:     wxClipboard implementation for wxGTK
   4 // Author:      Robert Roebling, Vadim Zeitlin
   5 // Id:          $Id$
   6 // Copyright:   (c) 1998 Robert Roebling
   7 //              (c) 2007 Vadim Zeitlin
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 // ============================================================================
  12 // declarations
  13 // ============================================================================
  14
  15 // ----------------------------------------------------------------------------
  16 // headers
  17 // ----------------------------------------------------------------------------
  18
  19 // For compilers that support precompilation, includes "wx.h".
  20 #include "wx/wxprec.h"
  21
  22 #if wxUSE_CLIPBOARD
  23
  24 #include "wx/clipbrd.h"
  25
  26 #ifndef WX_PRECOMP
  27     #include "wx/log.h"
  28     #include "wx/utils.h"
  29     #include "wx/dataobj.h"
  30 #endif
  31
  32 #include "wx/ptr_scpd.h"
  33 #include "wx/scopeguard.h"
  34
  35 #include "wx/gtk/private.h"
  36
  37 wxDECLARE_SCOPED_ARRAY(wxDataFormat, wxDataFormatArray)
  38 wxDEFINE_SCOPED_ARRAY(wxDataFormat, wxDataFormatArray)
  39
  40 // ----------------------------------------------------------------------------
  41 // data
  42 // ----------------------------------------------------------------------------
  43
  44 static GdkAtom  g_clipboardAtom   = 0;
  45 static GdkAtom  g_targetsAtom     = 0;
  46 static GdkAtom  g_timestampAtom   = 0;
  47
  48 #if wxUSE_UNICODE
  49 extern GdkAtom g_altTextAtom;
  50 #endif
  51
  52 // the trace mask we use with wxLogTrace() - call
  53 // wxLog::AddTraceMask(TRACE_CLIPBOARD) to enable the trace messages from here
  54 // (there will be a *lot* of them!)
  55 #define TRACE_CLIPBOARD _T("clipboard")
  56
  57 // ----------------------------------------------------------------------------
  58 // wxClipboardSync: used to perform clipboard operations synchronously
  59 // ----------------------------------------------------------------------------
  60
  61 // constructing this object on stack will wait wait until the latest clipboard
  62 // operation is finished on block exit
  63 //
  64 // notice that there can be no more than one such object alive at any moment,
  65 // i.e. reentrancies are not allowed
  66 class wxClipboardSync
  67 {
  68 public:
  69     wxClipboardSync(wxClipboard& clipboard)
  70     {
  71         wxASSERT_MSG( !ms_clipboard, _T("reentrancy in clipboard code") );
  72         ms_clipboard = &clipboard;
  73     }
  74
  75     ~wxClipboardSync()
  76     {
  77         while ( ms_clipboard )
  78             gtk_main_iteration();
  79     }
  80
  81     // this method must be called by GTK+ callbacks to indicate that we got the
  82     // result for our clipboard operation
  83     static void OnDone(wxClipboard * WXUNUSED_UNLESS_DEBUG(clipboard))
  84     {
  85         wxASSERT_MSG( clipboard == ms_clipboard,
  86                         _T("got notification for alien clipboard") );
  87
  88         ms_clipboard = NULL;
  89     }
  90
  91     // this method should be called if it's possible that no async clipboard
  92     // operation is currently in progress (like it can be the case when the
  93     // clipboard is cleared but not because we asked about it), it should only
  94     // be called if such situation is expected -- otherwise call OnDone() which
  95     // would assert in this case
  96     static void OnDoneIfInProgress(wxClipboard *clipboard)
  97     {
  98         if ( ms_clipboard )
  99             OnDone(clipboard);
 100     }
 101
 102 private:
 103     static wxClipboard *ms_clipboard;
 104
 105     DECLARE_NO_COPY_CLASS(wxClipboardSync)
 106 };
 107
 108 wxClipboard *wxClipboardSync::ms_clipboard = NULL;
 109
 110 // ============================================================================
 111 // clipboard ca;backs implementation
 112 // ============================================================================
 113
 114 //-----------------------------------------------------------------------------
 115 // "selection_received" for targets
 116 //-----------------------------------------------------------------------------
 117
 118 extern "C" {
 119 static void
 120 targets_selection_received( GtkWidget *WXUNUSED(widget),
 121                             GtkSelectionData *selection_data,
 122                             guint32 WXUNUSED(time),
 123                             wxClipboard *clipboard )
 124 {
 125     if ( !clipboard )
 126         return;
 127
 128     wxON_BLOCK_EXIT1(wxClipboardSync::OnDone, clipboard);
 129
 130     if ( !selection_data || selection_data->length <= 0 )
 131         return;
 132
 133     // make sure we got the data in the correct form
 134     GdkAtom type = selection_data->type;
 135     if ( type != GDK_SELECTION_TYPE_ATOM )
 136     {
 137         if ( strcmp(wxGtkString(gdk_atom_name(type)), "TARGETS") != 0 )
 138         {
 139             wxLogTrace( TRACE_CLIPBOARD,
 140                         _T("got unsupported clipboard target") );
 141
 142             return;
 143         }
 144     }
 145
 146 #ifdef __WXDEBUG__
 147     // it's not really a format, of course, but we can reuse its GetId() method
 148     // to format this atom as string
 149     wxDataFormat clip(selection_data->selection);
 150     wxLogTrace( TRACE_CLIPBOARD,
 151                 wxT("Received available formats for clipboard %s"),
 152                 clip.GetId().c_str() );
 153 #endif // __WXDEBUG__
 154
 155     // the atoms we received, holding a list of targets (= formats)
 156     const GdkAtom * const atoms = (GdkAtom *)selection_data->data;
 157     for ( size_t i = 0; i < selection_data->length/sizeof(GdkAtom); i++ )
 158     {
 159         const wxDataFormat format(atoms[i]);
 160
 161         wxLogTrace(TRACE_CLIPBOARD, wxT("\t%s"), format.GetId().c_str());
 162
 163         if ( clipboard->GTKOnTargetReceived(format) )
 164             return;
 165     }
 166 }
 167 }
 168
 169 bool wxClipboard::GTKOnTargetReceived(const wxDataFormat& format)
 170 {
 171     if ( format != m_targetRequested )
 172         return false;
 173
 174     m_formatSupported = true;
 175     return true;
 176 }
 177
 178 //-----------------------------------------------------------------------------
 179 // "selection_received" for the actual data
 180 //-----------------------------------------------------------------------------
 181
 182 extern "C" {
 183 static void
 184 selection_received( GtkWidget *WXUNUSED(widget),
 185                     GtkSelectionData *selection_data,
 186                     guint32 WXUNUSED(time),
 187                     wxClipboard *clipboard )
 188 {
 189     if ( !clipboard )
 190         return;
 191
 192     wxON_BLOCK_EXIT1(wxClipboardSync::OnDone, clipboard);
 193
 194     if ( !selection_data || selection_data->length <= 0 )
 195         return;
 196
 197     clipboard->GTKOnSelectionReceived(*selection_data);
 198 }
 199 }
 200
 201 //-----------------------------------------------------------------------------
 202 // "selection_clear"
 203 //-----------------------------------------------------------------------------
 204
 205 extern "C" {
 206 static gint
 207 selection_clear_clip( GtkWidget *WXUNUSED(widget), GdkEventSelection *event )
 208 {
 209     wxClipboard * const clipboard = wxTheClipboard;
 210     if ( !clipboard )
 211         return TRUE;
 212
 213     // notice the use of OnDoneIfInProgress() here instead of just OnDone():
 214     // it's perfectly possible that we're receiving this notification from GTK+
 215     // even though we hadn't cleared the clipboard ourselves but because
 216     // another application (or even another window in the same program)
 217     // acquired it
 218     wxON_BLOCK_EXIT1(wxClipboardSync::OnDoneIfInProgress, clipboard);
 219
 220     wxClipboard::Kind kind;
 221     if (event->selection == GDK_SELECTION_PRIMARY)
 222     {
 223         wxLogTrace(TRACE_CLIPBOARD, wxT("Lost primary selection" ));
 224
 225         kind = wxClipboard::Primary;
 226     }
 227     else if (event->selection == g_clipboardAtom)
 228     {
 229         wxLogTrace(TRACE_CLIPBOARD, wxT("Lost clipboard" ));
 230
 231         kind = wxClipboard::Clipboard;
 232     }
 233     else // some other selection, we're not concerned
 234     {
 235         return FALSE;
 236     }
 237
 238     // the clipboard is no longer in our hands, we don't need data any more
 239     clipboard->GTKClearData(kind);
 240
 241     return TRUE;
 242 }
 243 }
 244
 245 //-----------------------------------------------------------------------------
 246 // selection handler for supplying data
 247 //-----------------------------------------------------------------------------
 248
 249 extern "C" {
 250 static void
 251 selection_handler( GtkWidget *WXUNUSED(widget),
 252                    GtkSelectionData *selection_data,
 253                    guint WXUNUSED(info),
 254                    guint WXUNUSED(time),
 255                    gpointer signal_data )
 256 {
 257     wxClipboard * const clipboard = wxTheClipboard;
 258     if ( !clipboard )
 259         return;
 260
 261     wxDataObject * const data = clipboard->GTKGetDataObject();
 262     if ( !data )
 263         return;
 264
 265     // ICCCM says that TIMESTAMP is a required atom.
 266     // In particular, it satisfies Klipper, which polls
 267     // TIMESTAMP to see if the clipboards content has changed.
 268     // It shall return the time which was used to set the data.
 269     if (selection_data->target == g_timestampAtom)
 270     {
 271         guint timestamp = GPOINTER_TO_UINT (signal_data);
 272         gtk_selection_data_set(selection_data,
 273                                GDK_SELECTION_TYPE_INTEGER,
 274                                32,
 275                                (guchar*)&(timestamp),
 276                                sizeof(timestamp));
 277         wxLogTrace(TRACE_CLIPBOARD,
 278                    _T("Clipboard TIMESTAMP requested, returning timestamp=%u"),
 279                    timestamp);
 280         return;
 281     }
 282
 283     wxDataFormat format( selection_data->target );
 284
 285 #ifdef __WXDEBUG__
 286     wxLogTrace(TRACE_CLIPBOARD,
 287                _T("clipboard data in format %s, GtkSelectionData is target=%s type=%s selection=%s timestamp=%u"),
 288                format.GetId().c_str(),
 289                wxString::FromAscii(wxGtkString(gdk_atom_name(selection_data->target))).c_str(),
 290                wxString::FromAscii(wxGtkString(gdk_atom_name(selection_data->type))).c_str(),
 291                wxString::FromAscii(wxGtkString(gdk_atom_name(selection_data->selection))).c_str(),
 292                GPOINTER_TO_UINT( signal_data )
 293                );
 294 #endif
 295
 296     if (!data->IsSupportedFormat( format )) return;
 297
 298     int size = data->GetDataSize( format );
 299
 300     if (size == 0) return;
 301
 302     wxCharBuffer buf(size);
 303
 304     // text data must be returned in UTF8 if format is wxDF_UNICODETEXT
 305     data->GetDataHere( format, buf.data() );
 306
 307     // use UTF8_STRING format if requested in Unicode build but just plain
 308     // STRING one in ANSI or if explicitly asked in Unicode
 309 #if wxUSE_UNICODE
 310     if (format == wxDataFormat(wxDF_UNICODETEXT))
 311     {
 312         gtk_selection_data_set_text(
 313             selection_data,
 314             (const gchar*)buf.data(),
 315             size );
 316     }
 317     else
 318 #endif
 319     {
 320         gtk_selection_data_set(
 321             selection_data,
 322             GDK_SELECTION_TYPE_STRING,
 323             8*sizeof(gchar),
 324             (const guchar*)buf.data(),
 325             size );
 326     }
 327 }
 328 }
 329
 330 void wxClipboard::GTKOnSelectionReceived(const GtkSelectionData& sel)
 331 {
 332     wxCHECK_RET( m_receivedData, _T("should be inside GetData()") );
 333
 334     const wxDataFormat format(sel.target);
 335     wxLogTrace(TRACE_CLIPBOARD, _T("Received selection %s"),
 336                format.GetId().c_str());
 337
 338     if ( !m_receivedData->IsSupportedFormat(format) )
 339         return;
 340
 341     m_receivedData->SetData(format, sel.length, sel.data);
 342     m_formatSupported = true;
 343 }
 344
 345 // ============================================================================
 346 // wxClipboard implementation
 347 // ============================================================================
 348
 349 // ----------------------------------------------------------------------------
 350 // wxClipboard ctor/dtor
 351 // ----------------------------------------------------------------------------
 352
 353 IMPLEMENT_DYNAMIC_CLASS(wxClipboard,wxObject)
 354
 355 wxClipboard::wxClipboard()
 356 {
 357     m_open = false;
 358
 359     m_dataPrimary =
 360     m_dataClipboard =
 361     m_receivedData = NULL;
 362
 363     m_formatSupported = false;
 364     m_targetRequested = 0;
 365
 366     // we use m_targetsWidget to query what formats are available
 367     m_targetsWidget = gtk_window_new( GTK_WINDOW_POPUP );
 368     gtk_widget_realize( m_targetsWidget );
 369
 370     g_signal_connect (m_targetsWidget, "selection_received",
 371                       G_CALLBACK (targets_selection_received), this);
 372
 373     // we use m_clipboardWidget to get and to offer data
 374     m_clipboardWidget = gtk_window_new( GTK_WINDOW_POPUP );
 375     gtk_widget_realize( m_clipboardWidget );
 376
 377     g_signal_connect (m_clipboardWidget, "selection_received",
 378                       G_CALLBACK (selection_received), this);
 379
 380     g_signal_connect (m_clipboardWidget, "selection_clear_event",
 381                       G_CALLBACK (selection_clear_clip), NULL);
 382
 383     // initialize atoms we use if not done yet
 384     if ( !g_clipboardAtom )
 385         g_clipboardAtom = gdk_atom_intern( "CLIPBOARD", FALSE );
 386     if ( !g_targetsAtom )
 387         g_targetsAtom = gdk_atom_intern ("TARGETS", FALSE);
 388     if ( !g_timestampAtom )
 389         g_timestampAtom = gdk_atom_intern ("TIMESTAMP", FALSE);
 390 }
 391
 392 wxClipboard::~wxClipboard()
 393 {
 394     Clear();
 395
 396     gtk_widget_destroy( m_clipboardWidget );
 397     gtk_widget_destroy( m_targetsWidget );
 398 }
 399
 400 // ----------------------------------------------------------------------------
 401 // wxClipboard helper functions
 402 // ----------------------------------------------------------------------------
 403
 404 GdkAtom wxClipboard::GTKGetClipboardAtom() const
 405 {
 406     return m_usePrimary ? (GdkAtom)GDK_SELECTION_PRIMARY
 407                         : g_clipboardAtom;
 408 }
 409
 410 void wxClipboard::GTKClearData(Kind kind)
 411 {
 412     wxDataObject *&data = Data(kind);
 413     if ( data )
 414     {
 415         delete data;
 416         data = NULL;
 417     }
 418 }
 419
 420 bool wxClipboard::SetSelectionOwner(bool set)
 421 {
 422     bool rc = gtk_selection_owner_set
 423               (
 424                 set ? m_clipboardWidget : NULL,
 425                 GTKGetClipboardAtom(),
 426                 (guint32)GDK_CURRENT_TIME
 427               );
 428
 429     if ( !rc )
 430     {
 431         wxLogTrace(TRACE_CLIPBOARD, _T("Failed to %sset selection owner"),
 432                    set ? _T("") : _T("un"));
 433     }
 434
 435     return rc;
 436 }
 437
 438 void wxClipboard::AddSupportedTarget(GdkAtom atom)
 439 {
 440     gtk_selection_add_target
 441     (
 442         m_clipboardWidget,
 443         GTKGetClipboardAtom(),
 444         atom,
 445         0 // info (same as client data) unused
 446     );
 447 }
 448
 449 bool wxClipboard::DoIsSupported(const wxDataFormat& format)
 450 {
 451     wxCHECK_MSG( format, false, wxT("invalid clipboard format") );
 452
 453     wxLogTrace(TRACE_CLIPBOARD, wxT("Checking if format %s is available"),
 454                format.GetId().c_str());
 455
 456     // these variables will be used by our GTKOnTargetReceived()
 457     m_targetRequested = format;
 458     m_formatSupported = false;
 459
 460     // block until m_formatSupported is set from targets_selection_received
 461     // callback
 462     {
 463         wxClipboardSync sync(*this);
 464
 465         gtk_selection_convert( m_targetsWidget,
 466                                GTKGetClipboardAtom(),
 467                                g_targetsAtom,
 468                                (guint32) GDK_CURRENT_TIME );
 469     }
 470
 471     return m_formatSupported;
 472 }
 473
 474 // ----------------------------------------------------------------------------
 475 // wxClipboard public API implementation
 476 // ----------------------------------------------------------------------------
 477
 478 void wxClipboard::Clear()
 479 {
 480     if ( gdk_selection_owner_get(GTKGetClipboardAtom()) ==
 481             m_clipboardWidget->window )
 482     {
 483         wxClipboardSync sync(*this);
 484
 485         // this will result in selection_clear_clip callback being called and
 486         // it will free our data
 487         SetSelectionOwner(false);
 488     }
 489
 490     m_targetRequested = 0;
 491     m_formatSupported = false;
 492 }
 493
 494 bool wxClipboard::Open()
 495 {
 496     wxCHECK_MSG( !m_open, false, wxT("clipboard already open") );
 497
 498     m_open = true;
 499
 500     return true;
 501 }
 502
 503 bool wxClipboard::SetData( wxDataObject *data )
 504 {
 505     wxCHECK_MSG( m_open, false, wxT("clipboard not open") );
 506
 507     wxCHECK_MSG( data, false, wxT("data is invalid") );
 508
 509     Clear();
 510
 511     return AddData( data );
 512 }
 513
 514 bool wxClipboard::AddData( wxDataObject *data )
 515 {
 516     wxCHECK_MSG( m_open, false, wxT("clipboard not open") );
 517
 518     wxCHECK_MSG( data, false, wxT("data is invalid") );
 519
 520     // we can only store one wxDataObject so clear the old one
 521     Clear();
 522
 523     Data() = data;
 524
 525     // get formats from wxDataObjects
 526     const size_t count = data->GetFormatCount();
 527     wxDataFormatArray formats(new wxDataFormat[count]);
 528     data->GetAllFormats(formats.get());
 529
 530     // always provide TIMESTAMP as a target, see comments in selection_handler
 531     // for explanation
 532     AddSupportedTarget(g_timestampAtom);
 533
 534     for ( size_t i = 0; i < count; i++ )
 535     {
 536         const wxDataFormat format(formats[i]);
 537
 538         wxLogTrace(TRACE_CLIPBOARD, wxT("Adding support for %s"),
 539                    format.GetId().c_str());
 540
 541         AddSupportedTarget(format);
 542     }
 543
 544     g_signal_connect (m_clipboardWidget, "selection_get",
 545                       G_CALLBACK (selection_handler),
 546                       GUINT_TO_POINTER (gtk_get_current_event_time()) );
 547
 548     // tell the world we offer clipboard data
 549     return SetSelectionOwner();
 550 }
 551
 552 void wxClipboard::Close()
 553 {
 554     wxCHECK_RET( m_open, wxT("clipboard not open") );
 555
 556     m_open = false;
 557 }
 558
 559 bool wxClipboard::IsOpened() const
 560 {
 561     return m_open;
 562 }
 563
 564 bool wxClipboard::IsSupported( const wxDataFormat& format )
 565 {
 566     if ( DoIsSupported(format) )
 567         return true;
 568
 569 #if wxUSE_UNICODE
 570     if ( format == wxDF_UNICODETEXT )
 571     {
 572         // also with plain STRING format
 573         return DoIsSupported(g_altTextAtom);
 574     }
 575 #endif // wxUSE_UNICODE
 576
 577     return false;
 578 }
 579
 580 bool wxClipboard::GetData( wxDataObject& data )
 581 {
 582     wxCHECK_MSG( m_open, false, wxT("clipboard not open") );
 583
 584     // get all supported formats from wxDataObjects
 585     const size_t count = data.GetFormatCount();
 586     wxDataFormatArray formats(new wxDataFormat[count]);
 587     data.GetAllFormats(formats.get());
 588
 589     for ( size_t i = 0; i < count; i++ )
 590     {
 591         const wxDataFormat format(formats[i]);
 592
 593         // is this format supported by clipboard ?
 594         if ( !DoIsSupported(format) )
 595             continue;
 596
 597         wxLogTrace(TRACE_CLIPBOARD, wxT("Requesting format %s"),
 598                    format.GetId().c_str());
 599
 600         // these variables will be used by our GTKOnSelectionReceived()
 601         m_receivedData = &data;
 602         m_formatSupported = false;
 603
 604         {
 605             wxClipboardSync sync(*this);
 606
 607             gtk_selection_convert(m_clipboardWidget,
 608                                   GTKGetClipboardAtom(),
 609                                   format,
 610                                   (guint32) GDK_CURRENT_TIME );
 611         } // wait until we get the results
 612
 613         /*
 614            Normally this is a true error as we checked for the presence of such
 615            data before, but there are applications that may return an empty
 616            string (e.g. Gnumeric-1.6.1 on Linux if an empty cell is copied)
 617            which would produce a false error message here, so we check for the
 618            size of the string first. With ANSI, GetDataSize returns an extra
 619            value (for the closing null?), with unicode, the exact number of
 620            tokens is given (that is more than 1 for non-ASCII characters)
 621            (tested with Gnumeric-1.6.1 and OpenOffice.org-2.0.2)
 622          */
 623 #if wxUSE_UNICODE
 624         if ( format != wxDF_UNICODETEXT || data.GetDataSize(format) > 0 )
 625 #else // !UNICODE
 626         if ( format != wxDF_TEXT || data.GetDataSize(format) > 1 )
 627 #endif // UNICODE / !UNICODE
 628         {
 629             wxCHECK_MSG( m_formatSupported, false,
 630                          wxT("error retrieving data from clipboard") );
 631         }
 632
 633         return true;
 634     }
 635
 636     wxLogTrace(TRACE_CLIPBOARD, wxT("GetData(): format not found"));
 637
 638     return false;
 639 }
 640
 641 #endif // wxUSE_CLIPBOARD