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 // __WXDEBUG__
 295
 296     if ( !data->IsSupportedFormat( format ) )
 297         return;
 298
 299     int size = data->GetDataSize( format );
 300     if ( !size )
 301         return;
 302
 303     wxCharBuffer buf(size - 1); // it adds 1 internally (for NUL)
 304
 305     // text data must be returned in UTF8 if format is wxDF_UNICODETEXT
 306     if ( !data->GetDataHere(format, buf.data()) )
 307         return;
 308
 309     // use UTF8_STRING format if requested in Unicode build but just plain
 310     // STRING one in ANSI or if explicitly asked in Unicode
 311 #if wxUSE_UNICODE
 312     if (format == wxDataFormat(wxDF_UNICODETEXT))
 313     {
 314         gtk_selection_data_set_text(
 315             selection_data,
 316             (const gchar*)buf.data(),
 317             size );
 318     }
 319     else
 320 #endif // wxUSE_UNICODE
 321     {
 322         gtk_selection_data_set(
 323             selection_data,
 324             GDK_SELECTION_TYPE_STRING,
 325             8*sizeof(gchar),
 326             (const guchar*)buf.data(),
 327             size );
 328     }
 329 }
 330 }
 331
 332 void wxClipboard::GTKOnSelectionReceived(const GtkSelectionData& sel)
 333 {
 334     wxCHECK_RET( m_receivedData, _T("should be inside GetData()") );
 335
 336     const wxDataFormat format(sel.target);
 337     wxLogTrace(TRACE_CLIPBOARD, _T("Received selection %s"),
 338                format.GetId().c_str());
 339
 340     if ( !m_receivedData->IsSupportedFormat(format) )
 341         return;
 342
 343     m_receivedData->SetData(format, sel.length, sel.data);
 344     m_formatSupported = true;
 345 }
 346
 347 // ============================================================================
 348 // wxClipboard implementation
 349 // ============================================================================
 350
 351 // ----------------------------------------------------------------------------
 352 // wxClipboard ctor/dtor
 353 // ----------------------------------------------------------------------------
 354
 355 IMPLEMENT_DYNAMIC_CLASS(wxClipboard,wxObject)
 356
 357 wxClipboard::wxClipboard()
 358 {
 359     m_open = false;
 360
 361     m_dataPrimary =
 362     m_dataClipboard =
 363     m_receivedData = NULL;
 364
 365     m_formatSupported = false;
 366     m_targetRequested = 0;
 367
 368     // we use m_targetsWidget to query what formats are available
 369     m_targetsWidget = gtk_window_new( GTK_WINDOW_POPUP );
 370     gtk_widget_realize( m_targetsWidget );
 371
 372     g_signal_connect (m_targetsWidget, "selection_received",
 373                       G_CALLBACK (targets_selection_received), this);
 374
 375     // we use m_clipboardWidget to get and to offer data
 376     m_clipboardWidget = gtk_window_new( GTK_WINDOW_POPUP );
 377     gtk_widget_realize( m_clipboardWidget );
 378
 379     g_signal_connect (m_clipboardWidget, "selection_received",
 380                       G_CALLBACK (selection_received), this);
 381
 382     g_signal_connect (m_clipboardWidget, "selection_clear_event",
 383                       G_CALLBACK (selection_clear_clip), NULL);
 384
 385     // initialize atoms we use if not done yet
 386     if ( !g_clipboardAtom )
 387         g_clipboardAtom = gdk_atom_intern( "CLIPBOARD", FALSE );
 388     if ( !g_targetsAtom )
 389         g_targetsAtom = gdk_atom_intern ("TARGETS", FALSE);
 390     if ( !g_timestampAtom )
 391         g_timestampAtom = gdk_atom_intern ("TIMESTAMP", FALSE);
 392 }
 393
 394 wxClipboard::~wxClipboard()
 395 {
 396     Clear();
 397
 398     gtk_widget_destroy( m_clipboardWidget );
 399     gtk_widget_destroy( m_targetsWidget );
 400 }
 401
 402 // ----------------------------------------------------------------------------
 403 // wxClipboard helper functions
 404 // ----------------------------------------------------------------------------
 405
 406 GdkAtom wxClipboard::GTKGetClipboardAtom() const
 407 {
 408     return m_usePrimary ? (GdkAtom)GDK_SELECTION_PRIMARY
 409                         : g_clipboardAtom;
 410 }
 411
 412 void wxClipboard::GTKClearData(Kind kind)
 413 {
 414     wxDataObject *&data = Data(kind);
 415     if ( data )
 416     {
 417         delete data;
 418         data = NULL;
 419     }
 420 }
 421
 422 bool wxClipboard::SetSelectionOwner(bool set)
 423 {
 424     bool rc = gtk_selection_owner_set
 425               (
 426                 set ? m_clipboardWidget : NULL,
 427                 GTKGetClipboardAtom(),
 428                 (guint32)GDK_CURRENT_TIME
 429               );
 430
 431     if ( !rc )
 432     {
 433         wxLogTrace(TRACE_CLIPBOARD, _T("Failed to %sset selection owner"),
 434                    set ? _T("") : _T("un"));
 435     }
 436
 437     return rc;
 438 }
 439
 440 void wxClipboard::AddSupportedTarget(GdkAtom atom)
 441 {
 442     gtk_selection_add_target
 443     (
 444         m_clipboardWidget,
 445         GTKGetClipboardAtom(),
 446         atom,
 447         0 // info (same as client data) unused
 448     );
 449 }
 450
 451 bool wxClipboard::DoIsSupported(const wxDataFormat& format)
 452 {
 453     wxCHECK_MSG( format, false, wxT("invalid clipboard format") );
 454
 455     wxLogTrace(TRACE_CLIPBOARD, wxT("Checking if format %s is available"),
 456                format.GetId().c_str());
 457
 458     // these variables will be used by our GTKOnTargetReceived()
 459     m_targetRequested = format;
 460     m_formatSupported = false;
 461
 462     // block until m_formatSupported is set from targets_selection_received
 463     // callback
 464     {
 465         wxClipboardSync sync(*this);
 466
 467         gtk_selection_convert( m_targetsWidget,
 468                                GTKGetClipboardAtom(),
 469                                g_targetsAtom,
 470                                (guint32) GDK_CURRENT_TIME );
 471     }
 472
 473     return m_formatSupported;
 474 }
 475
 476 // ----------------------------------------------------------------------------
 477 // wxClipboard public API implementation
 478 // ----------------------------------------------------------------------------
 479
 480 void wxClipboard::Clear()
 481 {
 482     if ( gdk_selection_owner_get(GTKGetClipboardAtom()) ==
 483             m_clipboardWidget->window )
 484     {
 485         wxClipboardSync sync(*this);
 486
 487         // this will result in selection_clear_clip callback being called and
 488         // it will free our data
 489         SetSelectionOwner(false);
 490     }
 491
 492     m_targetRequested = 0;
 493     m_formatSupported = false;
 494 }
 495
 496 bool wxClipboard::Open()
 497 {
 498     wxCHECK_MSG( !m_open, false, wxT("clipboard already open") );
 499
 500     m_open = true;
 501
 502     return true;
 503 }
 504
 505 bool wxClipboard::SetData( wxDataObject *data )
 506 {
 507     wxCHECK_MSG( m_open, false, wxT("clipboard not open") );
 508
 509     wxCHECK_MSG( data, false, wxT("data is invalid") );
 510
 511     Clear();
 512
 513     return AddData( data );
 514 }
 515
 516 bool wxClipboard::AddData( wxDataObject *data )
 517 {
 518     wxCHECK_MSG( m_open, false, wxT("clipboard not open") );
 519
 520     wxCHECK_MSG( data, false, wxT("data is invalid") );
 521
 522     // we can only store one wxDataObject so clear the old one
 523     Clear();
 524
 525     Data() = data;
 526
 527     // get formats from wxDataObjects
 528     const size_t count = data->GetFormatCount();
 529     wxDataFormatArray formats(new wxDataFormat[count]);
 530     data->GetAllFormats(formats.get());
 531
 532     // always provide TIMESTAMP as a target, see comments in selection_handler
 533     // for explanation
 534     AddSupportedTarget(g_timestampAtom);
 535
 536     for ( size_t i = 0; i < count; i++ )
 537     {
 538         const wxDataFormat format(formats[i]);
 539
 540         wxLogTrace(TRACE_CLIPBOARD, wxT("Adding support for %s"),
 541                    format.GetId().c_str());
 542
 543         AddSupportedTarget(format);
 544     }
 545
 546     g_signal_connect (m_clipboardWidget, "selection_get",
 547                       G_CALLBACK (selection_handler),
 548                       GUINT_TO_POINTER (gtk_get_current_event_time()) );
 549
 550     // tell the world we offer clipboard data
 551     return SetSelectionOwner();
 552 }
 553
 554 void wxClipboard::Close()
 555 {
 556     wxCHECK_RET( m_open, wxT("clipboard not open") );
 557
 558     m_open = false;
 559 }
 560
 561 bool wxClipboard::IsOpened() const
 562 {
 563     return m_open;
 564 }
 565
 566 bool wxClipboard::IsSupported( const wxDataFormat& format )
 567 {
 568     if ( DoIsSupported(format) )
 569         return true;
 570
 571 #if wxUSE_UNICODE
 572     if ( format == wxDF_UNICODETEXT )
 573     {
 574         // also with plain STRING format
 575         return DoIsSupported(g_altTextAtom);
 576     }
 577 #endif // wxUSE_UNICODE
 578
 579     return false;
 580 }
 581
 582 bool wxClipboard::GetData( wxDataObject& data )
 583 {
 584     wxCHECK_MSG( m_open, false, wxT("clipboard not open") );
 585
 586     // get all supported formats from wxDataObjects
 587     const size_t count = data.GetFormatCount();
 588     wxDataFormatArray formats(new wxDataFormat[count]);
 589     data.GetAllFormats(formats.get());
 590
 591     for ( size_t i = 0; i < count; i++ )
 592     {
 593         const wxDataFormat format(formats[i]);
 594
 595         // is this format supported by clipboard ?
 596         if ( !DoIsSupported(format) )
 597             continue;
 598
 599         wxLogTrace(TRACE_CLIPBOARD, wxT("Requesting format %s"),
 600                    format.GetId().c_str());
 601
 602         // these variables will be used by our GTKOnSelectionReceived()
 603         m_receivedData = &data;
 604         m_formatSupported = false;
 605
 606         {
 607             wxClipboardSync sync(*this);
 608
 609             gtk_selection_convert(m_clipboardWidget,
 610                                   GTKGetClipboardAtom(),
 611                                   format,
 612                                   (guint32) GDK_CURRENT_TIME );
 613         } // wait until we get the results
 614
 615         /*
 616            Normally this is a true error as we checked for the presence of such
 617            data before, but there are applications that may return an empty
 618            string (e.g. Gnumeric-1.6.1 on Linux if an empty cell is copied)
 619            which would produce a false error message here, so we check for the
 620            size of the string first. With ANSI, GetDataSize returns an extra
 621            value (for the closing null?), with unicode, the exact number of
 622            tokens is given (that is more than 1 for non-ASCII characters)
 623            (tested with Gnumeric-1.6.1 and OpenOffice.org-2.0.2)
 624          */
 625 #if wxUSE_UNICODE
 626         if ( format != wxDF_UNICODETEXT || data.GetDataSize(format) > 0 )
 627 #else // !UNICODE
 628         if ( format != wxDF_TEXT || data.GetDataSize(format) > 1 )
 629 #endif // UNICODE / !UNICODE
 630         {
 631             wxCHECK_MSG( m_formatSupported, false,
 632                          wxT("error retrieving data from clipboard") );
 633         }
 634
 635         return true;
 636     }
 637
 638     wxLogTrace(TRACE_CLIPBOARD, wxT("GetData(): format not found"));
 639
 640     return false;
 641 }
 642
 643 #endif // wxUSE_CLIPBOARD