The Tor Browser: widget/gtk/nsDragService.cpp@ac0c01689b40

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

     1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

     2 /* vim: set ts=4 et sw=4 tw=80: */

     3 /* This Source Code Form is subject to the terms of the Mozilla Public

     4  * License, v. 2.0. If a copy of the MPL was not distributed with this

     5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     7 #include "nsDragService.h"

     8 #include "nsIObserverService.h"

     9 #include "nsWidgetsCID.h"

    10 #include "nsWindow.h"

    11 #include "nsIServiceManager.h"

    12 #include "nsXPCOM.h"

    13 #include "nsISupportsPrimitives.h"

    14 #include "nsIIOService.h"

    15 #include "nsIFileURL.h"

    16 #include "nsNetUtil.h"

    17 #include "prlog.h"

    18 #include "nsTArray.h"

    19 #include "nsPrimitiveHelpers.h"

    20 #include "prtime.h"

    21 #include "prthread.h"

    22 #include <gtk/gtk.h>

    23 #include <gdk/gdkx.h>

    24 #include "nsCRT.h"

    25 #include "mozilla/BasicEvents.h"

    26 #include "mozilla/Services.h"

    28 #include "gfxASurface.h"

    29 #include "gfxXlibSurface.h"

    30 #include "gfxContext.h"

    31 #include "nsImageToPixbuf.h"

    32 #include "nsPresContext.h"

    33 #include "nsIContent.h"

    34 #include "nsIDocument.h"

    35 #include "nsISelection.h"

    36 #include "nsViewManager.h"

    37 #include "nsIFrame.h"

    38 #include "nsGtkUtils.h"

    39 #include "mozilla/gfx/2D.h"

    40 #include "gfxPlatform.h"

    42 using namespace mozilla;

    43 using namespace mozilla::gfx;

    45 // This sets how opaque the drag image is

    46 #define DRAG_IMAGE_ALPHA_LEVEL 0.5

    48 // These values are copied from GtkDragResult (rather than using GtkDragResult

    49 // directly) so that this code can be compiled against versions of GTK+ that

    50 // do not have GtkDragResult.

    51 // GtkDragResult is available from GTK+ version 2.12.

    52 enum {

    53   MOZ_GTK_DRAG_RESULT_SUCCESS,

    54   MOZ_GTK_DRAG_RESULT_NO_TARGET

    55 };

    57 static PRLogModuleInfo *sDragLm = nullptr;

    59 // data used for synthetic periodic motion events sent to the source widget

    60 // grabbing real events for the drag.

    61 static guint sMotionEventTimerID;

    62 static GdkEvent *sMotionEvent;

    63 static GtkWidget *sGrabWidget;

    65 static const char gMimeListType[] = "application/x-moz-internal-item-list";

    66 static const char gMozUrlType[] = "_NETSCAPE_URL";

    67 static const char gTextUriListType[] = "text/uri-list";

    68 static const char gTextPlainUTF8Type[] = "text/plain;charset=utf-8";

    70 static void

    71 invisibleSourceDragBegin(GtkWidget        *aWidget,

    72                          GdkDragContext   *aContext,

    73                          gpointer          aData);

    75 static void

    76 invisibleSourceDragEnd(GtkWidget        *aWidget,

    77                        GdkDragContext   *aContext,

    78                        gpointer          aData);

    80 static gboolean

    81 invisibleSourceDragFailed(GtkWidget        *aWidget,

    82                           GdkDragContext   *aContext,

    83                           gint              aResult,

    84                           gpointer          aData);

    86 static void

    87 invisibleSourceDragDataGet(GtkWidget        *aWidget,

    88                            GdkDragContext   *aContext,

    89                            GtkSelectionData *aSelectionData,

    90                            guint             aInfo,

    91                            guint32           aTime,

    92                            gpointer          aData);

    94 nsDragService::nsDragService()

    95     : mScheduledTask(eDragTaskNone)

    96     , mTaskSource(0)

    97 {

    98     // We have to destroy the hidden widget before the event loop stops

    99     // running.

   100     nsCOMPtr<nsIObserverService> obsServ =

   101         mozilla::services::GetObserverService();

   102     obsServ->AddObserver(this, "quit-application", false);

   104     // our hidden source widget

   105     mHiddenWidget = gtk_window_new(GTK_WINDOW_POPUP);

   106     // make sure that the widget is realized so that

   107     // we can use it as a drag source.

   108     gtk_widget_realize(mHiddenWidget);

   109     // hook up our internal signals so that we can get some feedback

   110     // from our drag source

   111     g_signal_connect(mHiddenWidget, "drag_begin",

   112                      G_CALLBACK(invisibleSourceDragBegin), this);

   113     g_signal_connect(mHiddenWidget, "drag_data_get",

   114                      G_CALLBACK(invisibleSourceDragDataGet), this);

   115     g_signal_connect(mHiddenWidget, "drag_end",

   116                      G_CALLBACK(invisibleSourceDragEnd), this);

   117     // drag-failed is available from GTK+ version 2.12

   118     guint dragFailedID = g_signal_lookup("drag-failed",

   119                                          G_TYPE_FROM_INSTANCE(mHiddenWidget));

   120     if (dragFailedID) {

   121         g_signal_connect_closure_by_id(mHiddenWidget, dragFailedID, 0,

   122                                        g_cclosure_new(G_CALLBACK(invisibleSourceDragFailed),

   123                                                       this, nullptr),

   124                                        FALSE);

   125     }

   127     // set up our logging module

   128     if (!sDragLm)

   129         sDragLm = PR_NewLogModule("nsDragService");

   130     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::nsDragService"));

   131     mCanDrop = false;

   132     mTargetDragDataReceived = false;

   133     mTargetDragData = 0;

   134     mTargetDragDataLen = 0;

   135 }

   137 nsDragService::~nsDragService()

   138 {

   139     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::~nsDragService"));

   140     if (mTaskSource)

   141         g_source_remove(mTaskSource);

   143 }

   145 NS_IMPL_ISUPPORTS_INHERITED(nsDragService, nsBaseDragService, nsIObserver)

   147 /* static */ nsDragService*

   148 nsDragService::GetInstance()

   149 {

   150     static const nsIID iid = NS_DRAGSERVICE_CID;

   151     nsCOMPtr<nsIDragService> dragService = do_GetService(iid);

   152     return static_cast<nsDragService*>(dragService.get());

   153     // We rely on XPCOM keeping a reference to the service.

   154 }

   156 // nsIObserver

   158 NS_IMETHODIMP

   159 nsDragService::Observe(nsISupports *aSubject, const char *aTopic,

   160                        const char16_t *aData)

   161 {

   162   if (!nsCRT::strcmp(aTopic, "quit-application")) {

   163     PR_LOG(sDragLm, PR_LOG_DEBUG,

   164            ("nsDragService::Observe(\"quit-application\")"));

   165     if (mHiddenWidget) {

   166       gtk_widget_destroy(mHiddenWidget);

   167       mHiddenWidget = 0;

   168     }

   169     TargetResetData();

   170   } else {

   171     NS_NOTREACHED("unexpected topic");

   172     return NS_ERROR_UNEXPECTED;

   173   }

   175   return NS_OK;

   176 }

   178 // Support for periodic drag events

   180 // http://www.whatwg.org/specs/web-apps/current-work/multipage/dnd.html#drag-and-drop-processing-model

   181 // and the Xdnd protocol both recommend that drag events are sent periodically,

   182 // but GTK does not normally provide this.

   183 //

   184 // Here GTK is periodically stimulated by copies of the most recent mouse

   185 // motion events so as to send drag position messages to the destination when

   186 // appropriate (after it has received a status event from the previous

   187 // message).

   188 //

   189 // (If events were sent only on the destination side then the destination

   190 // would have no message to which it could reply with a drag status.  Without

   191 // sending a drag status to the source, the destination would not be able to

   192 // change its feedback re whether it could accept the drop, and so the

   193 // source's behavior on drop will not be consistent.)

   195 static gboolean

   196 DispatchMotionEventCopy(gpointer aData)

   197 {

   198     // Clear the timer id before OnSourceGrabEventAfter is called during event

   199     // dispatch.

   200     sMotionEventTimerID = 0;

   202     GdkEvent *event = sMotionEvent;

   203     sMotionEvent = nullptr;

   204     // If there is no longer a grab on the widget, then the drag is over and

   205     // there is no need to continue drag motion.

   206     if (gtk_widget_has_grab(sGrabWidget)) {

   207         gtk_propagate_event(sGrabWidget, event);

   208     }

   209     gdk_event_free(event);

   211     // Cancel this timer;

   212     // We've already started another if the motion event was dispatched.

   213     return FALSE;

   214 }

   216 static void

   217 OnSourceGrabEventAfter(GtkWidget *widget, GdkEvent *event, gpointer user_data)

   218 {

   219     // If there is no longer a grab on the widget, then the drag motion is

   220     // over (though the data may not be fetched yet).

   221     if (!gtk_widget_has_grab(sGrabWidget))

   222         return;

   224     if (event->type == GDK_MOTION_NOTIFY) {

   225         if (sMotionEvent) {

   226             gdk_event_free(sMotionEvent);

   227         }

   228         sMotionEvent = gdk_event_copy(event);

   230         // Update the cursor position.  The last of these recorded gets used for

   231         // the NS_DRAGDROP_END event.

   232         nsDragService *dragService = static_cast<nsDragService*>(user_data);

   233         dragService->SetDragEndPoint(nsIntPoint(event->motion.x_root,

   234                                                 event->motion.y_root));

   235     } else if (sMotionEvent && (event->type == GDK_KEY_PRESS ||

   236                                 event->type == GDK_KEY_RELEASE)) {

   237         // Update modifier state from key events.

   238         sMotionEvent->motion.state = event->key.state;

   239     } else {

   240         return;

   241     }

   243     if (sMotionEventTimerID) {

   244         g_source_remove(sMotionEventTimerID);

   245     }

   247     // G_PRIORITY_DEFAULT_IDLE is lower priority than GDK's redraw idle source

   248     // and lower than GTK's idle source that sends drag position messages after

   249     // motion-notify signals.

   250     //

   251     // http://www.whatwg.org/specs/web-apps/current-work/multipage/dnd.html#drag-and-drop-processing-model

   252     // recommends an interval of 350ms +/- 200ms.

   253     sMotionEventTimerID =

   254         g_timeout_add_full(G_PRIORITY_DEFAULT_IDLE, 350,

   255                            DispatchMotionEventCopy, nullptr, nullptr);

   256 }

   258 static GtkWindow*

   259 GetGtkWindow(nsIDOMDocument *aDocument)

   260 {

   261     nsCOMPtr<nsIDocument> doc = do_QueryInterface(aDocument);

   262     if (!doc)

   263         return nullptr;

   265     nsCOMPtr<nsIPresShell> presShell = doc->GetShell();

   266     if (!presShell)

   267         return nullptr;

   269     nsRefPtr<nsViewManager> vm = presShell->GetViewManager();

   270     if (!vm)

   271         return nullptr;

   273     nsCOMPtr<nsIWidget> widget;

   274     vm->GetRootWidget(getter_AddRefs(widget));

   275     if (!widget)

   276         return nullptr;

   278     GtkWidget *gtkWidget =

   279         static_cast<nsWindow*>(widget.get())->GetMozContainerWidget();

   280     if (!gtkWidget)

   281         return nullptr;

   283     GtkWidget *toplevel = nullptr;

   284     toplevel = gtk_widget_get_toplevel(gtkWidget);

   285     if (!GTK_IS_WINDOW(toplevel))

   286         return nullptr;

   288     return GTK_WINDOW(toplevel);

   289 }

   291 // nsIDragService

   293 NS_IMETHODIMP

   294 nsDragService::InvokeDragSession(nsIDOMNode *aDOMNode,

   295                                  nsISupportsArray * aArrayTransferables,

   296                                  nsIScriptableRegion * aRegion,

   297                                  uint32_t aActionType)

   298 {

   299     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::InvokeDragSession"));

   301     // If the previous source drag has not yet completed, signal handlers need

   302     // to be removed from sGrabWidget and dragend needs to be dispatched to

   303     // the source node, but we can't call EndDragSession yet because we don't

   304     // know whether or not the drag succeeded.

   305     if (mSourceNode)

   306         return NS_ERROR_NOT_AVAILABLE;

   308     nsresult rv = nsBaseDragService::InvokeDragSession(aDOMNode,

   309                                                        aArrayTransferables,

   310                                                        aRegion, aActionType);

   311     NS_ENSURE_SUCCESS(rv, rv);

   313     // make sure that we have an array of transferables to use

   314     if (!aArrayTransferables)

   315         return NS_ERROR_INVALID_ARG;

   316     // set our reference to the transferables.  this will also addref

   317     // the transferables since we're going to hang onto this beyond the

   318     // length of this call

   319     mSourceDataItems = aArrayTransferables;

   320     // get the list of items we offer for drags

   321     GtkTargetList *sourceList = GetSourceList();

   323     if (!sourceList)

   324         return NS_OK;

   326     // stored temporarily until the drag-begin signal has been received

   327     mSourceRegion = aRegion;

   329     // save our action type

   330     GdkDragAction action = GDK_ACTION_DEFAULT;

   332     if (aActionType & DRAGDROP_ACTION_COPY)

   333         action = (GdkDragAction)(action | GDK_ACTION_COPY);

   334     if (aActionType & DRAGDROP_ACTION_MOVE)

   335         action = (GdkDragAction)(action | GDK_ACTION_MOVE);

   336     if (aActionType & DRAGDROP_ACTION_LINK)

   337         action = (GdkDragAction)(action | GDK_ACTION_LINK);

   339     // Create a fake event for the drag so we can pass the time (so to speak).

   340     // If we don't do this, then, when the timestamp for the pending button

   341     // release event is used for the ungrab, the ungrab can fail due to the

   342     // timestamp being _earlier_ than CurrentTime.

   343     GdkEvent event;

   344     memset(&event, 0, sizeof(GdkEvent));

   345     event.type = GDK_BUTTON_PRESS;

   346     event.button.window = gtk_widget_get_window(mHiddenWidget);

   347     event.button.time = nsWindow::GetLastUserInputTime();

   349     // Put the drag widget in the window group of the source node so that the

   350     // gtk_grab_add during gtk_drag_begin is effective.

   351     // gtk_window_get_group(nullptr) returns the default window group.

   352     GtkWindowGroup *window_group =

   353         gtk_window_get_group(GetGtkWindow(mSourceDocument));

   354     gtk_window_group_add_window(window_group,

   355                                 GTK_WINDOW(mHiddenWidget));

   357 #if (MOZ_WIDGET_GTK == 3)

   358     // Get device for event source

   359     GdkDisplay *display = gdk_display_get_default();

   360     GdkDeviceManager *device_manager = gdk_display_get_device_manager(display);

   361     event.button.device = gdk_device_manager_get_client_pointer(device_manager);

   362 #endif

   364     // start our drag.

   365     GdkDragContext *context = gtk_drag_begin(mHiddenWidget,

   366                                              sourceList,

   367                                              action,

   368                                              1,

   369                                              &event);

   371     mSourceRegion = nullptr;

   373     if (context) {

   374         StartDragSession();

   376         // GTK uses another hidden window for receiving mouse events.

   377         sGrabWidget = gtk_window_group_get_current_grab(window_group);

   378         if (sGrabWidget) {

   379             g_object_ref(sGrabWidget);

   380             // Only motion and key events are required but connect to

   381             // "event-after" as this is never blocked by other handlers.

   382             g_signal_connect(sGrabWidget, "event-after",

   383                              G_CALLBACK(OnSourceGrabEventAfter), this);

   384         }

   385         // We don't have a drag end point yet.

   386         mEndDragPoint = nsIntPoint(-1, -1);

   387     }

   388     else {

   389         rv = NS_ERROR_FAILURE;

   390     }

   392     gtk_target_list_unref(sourceList);

   394     return rv;

   395 }

   397 bool

   398 nsDragService::SetAlphaPixmap(SourceSurface *aSurface,

   399                               GdkDragContext *aContext,

   400                               int32_t aXOffset,

   401                               int32_t aYOffset,

   402                               const nsIntRect& dragRect)

   403 {

   404 #if (MOZ_WIDGET_GTK == 2)

   405     GdkScreen* screen = gtk_widget_get_screen(mHiddenWidget);

   407     // Transparent drag icons need, like a lot of transparency-related things,

   408     // a compositing X window manager

   409     if (!gdk_screen_is_composited(screen))

   410       return false;

   412     GdkColormap* alphaColormap = gdk_screen_get_rgba_colormap(screen);

   413     if (!alphaColormap)

   414       return false;

   416     GdkPixmap* pixmap = gdk_pixmap_new(nullptr, dragRect.width, dragRect.height,

   417                                        gdk_colormap_get_visual(alphaColormap)->depth);

   418     if (!pixmap)

   419       return false;

   421     gdk_drawable_set_colormap(GDK_DRAWABLE(pixmap), alphaColormap);

   423     // Make a gfxXlibSurface wrapped around the pixmap to render on

   424     nsRefPtr<gfxASurface> xPixmapSurface =

   425          nsWindow::GetSurfaceForGdkDrawable(GDK_DRAWABLE(pixmap),

   426                                             dragRect.Size());

   427     if (!xPixmapSurface)

   428       return false;

   430     RefPtr<DrawTarget> dt =

   431     gfxPlatform::GetPlatform()->

   432       CreateDrawTargetForSurface(xPixmapSurface, IntSize(dragRect.width, dragRect.height));

   433     if (!dt)

   434       return false;

   436     // Clear it...

   437     dt->ClearRect(Rect(0, 0, dragRect.width, dragRect.height));

   439     // ...and paint the drag image with translucency

   440     dt->DrawSurface(aSurface,

   441                     Rect(0, 0, dragRect.width, dragRect.height),

   442                     Rect(0, 0, dragRect.width, dragRect.height),

   443                     DrawSurfaceOptions(),

   444                     DrawOptions(DRAG_IMAGE_ALPHA_LEVEL, CompositionOp::OP_SOURCE));

   446     // The drag transaction addrefs the pixmap, so we can just unref it from us here

   447     gtk_drag_set_icon_pixmap(aContext, alphaColormap, pixmap, nullptr,

   448                              aXOffset, aYOffset);

   449     g_object_unref(pixmap);

   450     return true;

   451 #else

   452     // TODO GTK3

   453     return false;

   454 #endif

   455 }

   457 NS_IMETHODIMP

   458 nsDragService::StartDragSession()

   459 {

   460     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::StartDragSession"));

   461     return nsBaseDragService::StartDragSession();

   462 }

   464 NS_IMETHODIMP

   465 nsDragService::EndDragSession(bool aDoneDrag)

   466 {

   467     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::EndDragSession %d",

   468                                    aDoneDrag));

   470     if (sGrabWidget) {

   471         g_signal_handlers_disconnect_by_func(sGrabWidget,

   472              FuncToGpointer(OnSourceGrabEventAfter), this);

   473         g_object_unref(sGrabWidget);

   474         sGrabWidget = nullptr;

   476         if (sMotionEventTimerID) {

   477             g_source_remove(sMotionEventTimerID);

   478             sMotionEventTimerID = 0;

   479         }

   480         if (sMotionEvent) {

   481             gdk_event_free(sMotionEvent);

   482             sMotionEvent = nullptr;

   483         }

   484     }

   486     // unset our drag action

   487     SetDragAction(DRAGDROP_ACTION_NONE);

   488     return nsBaseDragService::EndDragSession(aDoneDrag);

   489 }

   491 // nsIDragSession

   492 NS_IMETHODIMP

   493 nsDragService::SetCanDrop(bool aCanDrop)

   494 {

   495     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::SetCanDrop %d",

   496                                    aCanDrop));

   497     mCanDrop = aCanDrop;

   498     return NS_OK;

   499 }

   501 NS_IMETHODIMP

   502 nsDragService::GetCanDrop(bool *aCanDrop)

   503 {

   504     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::GetCanDrop"));

   505     *aCanDrop = mCanDrop;

   506     return NS_OK;

   507 }

   509 // count the number of URIs in some text/uri-list format data.

   510 static uint32_t

   511 CountTextUriListItems(const char *data,

   512                       uint32_t datalen)

   513 {

   514     const char *p = data;

   515     const char *endPtr = p + datalen;

   516     uint32_t count = 0;

   518     while (p < endPtr) {

   519         // skip whitespace (if any)

   520         while (p < endPtr && *p != '\0' && isspace(*p))

   521             p++;

   522         // if we aren't at the end of the line ...

   523         if (p != endPtr && *p != '\0' && *p != '\n' && *p != '\r')

   524             count++;

   525         // skip to the end of the line

   526         while (p < endPtr && *p != '\0' && *p != '\n')

   527             p++;

   528         p++; // skip the actual newline as well.

   529     }

   530     return count;

   531 }

   533 // extract an item from text/uri-list formatted data and convert it to

   534 // unicode.

   535 static void

   536 GetTextUriListItem(const char *data,

   537                    uint32_t datalen,

   538                    uint32_t aItemIndex,

   539                    char16_t **convertedText,

   540                    int32_t *convertedTextLen)

   541 {

   542     const char *p = data;

   543     const char *endPtr = p + datalen;

   544     unsigned int count = 0;

   546     *convertedText = nullptr;

   547     while (p < endPtr) {

   548         // skip whitespace (if any)

   549         while (p < endPtr && *p != '\0' && isspace(*p))

   550             p++;

   551         // if we aren't at the end of the line, we have a url

   552         if (p != endPtr && *p != '\0' && *p != '\n' && *p != '\r')

   553             count++;

   554         // this is the item we are after ...

   555         if (aItemIndex + 1 == count) {

   556             const char *q = p;

   557             while (q < endPtr && *q != '\0' && *q != '\n' && *q != '\r')

   558               q++;

   559             nsPrimitiveHelpers::ConvertPlatformPlainTextToUnicode(

   560                                 p, q - p, convertedText, convertedTextLen);

   561             break;

   562         }

   563         // skip to the end of the line

   564         while (p < endPtr && *p != '\0' && *p != '\n')

   565             p++;

   566         p++; // skip the actual newline as well.

   567     }

   569     // didn't find the desired item, so just pass the whole lot

   570     if (!*convertedText) {

   571         nsPrimitiveHelpers::ConvertPlatformPlainTextToUnicode(

   572                             data, datalen, convertedText, convertedTextLen);

   573     }

   574 }

   576 NS_IMETHODIMP

   577 nsDragService::GetNumDropItems(uint32_t * aNumItems)

   578 {

   579     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::GetNumDropItems"));

   581     if (!mTargetWidget) {

   582         PR_LOG(sDragLm, PR_LOG_DEBUG,

   583                ("*** warning: GetNumDropItems \

   584                called without a valid target widget!\n"));

   585         *aNumItems = 0;

   586         return NS_OK;

   587     }

   589     bool isList = IsTargetContextList();

   590     if (isList)

   591         mSourceDataItems->Count(aNumItems);

   592     else {

   593         GdkAtom gdkFlavor = gdk_atom_intern(gTextUriListType, FALSE);

   594         GetTargetDragData(gdkFlavor);

   595         if (mTargetDragData) {

   596             const char *data = reinterpret_cast<char*>(mTargetDragData);

   597             *aNumItems = CountTextUriListItems(data, mTargetDragDataLen);

   598         } else

   599             *aNumItems = 1;

   600     }

   601     PR_LOG(sDragLm, PR_LOG_DEBUG, ("%d items", *aNumItems));

   602     return NS_OK;

   603 }

   606 NS_IMETHODIMP

   607 nsDragService::GetData(nsITransferable * aTransferable,

   608                        uint32_t aItemIndex)

   609 {

   610     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::GetData %d", aItemIndex));

   612     // make sure that we have a transferable

   613     if (!aTransferable)

   614         return NS_ERROR_INVALID_ARG;

   616     if (!mTargetWidget) {

   617         PR_LOG(sDragLm, PR_LOG_DEBUG,

   618                ("*** warning: GetData \

   619                called without a valid target widget!\n"));

   620         return NS_ERROR_FAILURE;

   621     }

   623     // get flavor list that includes all acceptable flavors (including

   624     // ones obtained through conversion). Flavors are nsISupportsStrings

   625     // so that they can be seen from JS.

   626     nsCOMPtr<nsISupportsArray> flavorList;

   627     nsresult rv = aTransferable->FlavorsTransferableCanImport(

   628                         getter_AddRefs(flavorList));

   629     if (NS_FAILED(rv))

   630         return rv;

   632     // count the number of flavors

   633     uint32_t cnt;

   634     flavorList->Count(&cnt);

   635     unsigned int i;

   637     // check to see if this is an internal list

   638     bool isList = IsTargetContextList();

   640     if (isList) {

   641         PR_LOG(sDragLm, PR_LOG_DEBUG, ("it's a list..."));

   642         // find a matching flavor

   643         for (i = 0; i < cnt; ++i) {

   644             nsCOMPtr<nsISupports> genericWrapper;

   645             flavorList->GetElementAt(i, getter_AddRefs(genericWrapper));

   646             nsCOMPtr<nsISupportsCString> currentFlavor;

   647             currentFlavor = do_QueryInterface(genericWrapper);

   648             if (!currentFlavor)

   649                 continue;

   651             nsXPIDLCString flavorStr;

   652             currentFlavor->ToString(getter_Copies(flavorStr));

   653             PR_LOG(sDragLm,

   654                    PR_LOG_DEBUG,

   655                    ("flavor is %s\n", (const char *)flavorStr));

   656             // get the item with the right index

   657             nsCOMPtr<nsISupports> genericItem;

   658             mSourceDataItems->GetElementAt(aItemIndex,

   659                                            getter_AddRefs(genericItem));

   660             nsCOMPtr<nsITransferable> item(do_QueryInterface(genericItem));

   661             if (!item)

   662                 continue;

   664             nsCOMPtr<nsISupports> data;

   665             uint32_t tmpDataLen = 0;

   666             PR_LOG(sDragLm, PR_LOG_DEBUG,

   667                    ("trying to get transfer data for %s\n",

   668                    (const char *)flavorStr));

   669             rv = item->GetTransferData(flavorStr,

   670                                        getter_AddRefs(data),

   671                                        &tmpDataLen);

   672             if (NS_FAILED(rv)) {

   673                 PR_LOG(sDragLm, PR_LOG_DEBUG, ("failed.\n"));

   674                 continue;

   675             }

   676             PR_LOG(sDragLm, PR_LOG_DEBUG, ("succeeded.\n"));

   677             rv = aTransferable->SetTransferData(flavorStr,data,tmpDataLen);

   678             if (NS_FAILED(rv)) {

   679                 PR_LOG(sDragLm,

   680                        PR_LOG_DEBUG,

   681                        ("fail to set transfer data into transferable!\n"));

   682                 continue;

   683             }

   684             // ok, we got the data

   685             return NS_OK;

   686         }

   687         // if we got this far, we failed

   688         return NS_ERROR_FAILURE;

   689     }

   691     // Now walk down the list of flavors. When we find one that is

   692     // actually present, copy out the data into the transferable in that

   693     // format. SetTransferData() implicitly handles conversions.

   694     for ( i = 0; i < cnt; ++i ) {

   695         nsCOMPtr<nsISupports> genericWrapper;

   696         flavorList->GetElementAt(i,getter_AddRefs(genericWrapper));

   697         nsCOMPtr<nsISupportsCString> currentFlavor;

   698         currentFlavor = do_QueryInterface(genericWrapper);

   699         if (currentFlavor) {

   700             // find our gtk flavor

   701             nsXPIDLCString flavorStr;

   702             currentFlavor->ToString(getter_Copies(flavorStr));

   703             GdkAtom gdkFlavor = gdk_atom_intern(flavorStr, FALSE);

   704             PR_LOG(sDragLm, PR_LOG_DEBUG,

   705                    ("looking for data in type %s, gdk flavor %ld\n",

   706                    static_cast<const char*>(flavorStr), gdkFlavor));

   707             bool dataFound = false;

   708             if (gdkFlavor) {

   709                 GetTargetDragData(gdkFlavor);

   710             }

   711             if (mTargetDragData) {

   712                 PR_LOG(sDragLm, PR_LOG_DEBUG, ("dataFound = true\n"));

   713                 dataFound = true;

   714             }

   715             else {

   716                 PR_LOG(sDragLm, PR_LOG_DEBUG, ("dataFound = false\n"));

   718                 // Dragging and dropping from the file manager would cause us

   719                 // to parse the source text as a nsIFile URL.

   720                 if ( strcmp(flavorStr, kFileMime) == 0 ) {

   721                     gdkFlavor = gdk_atom_intern(kTextMime, FALSE);

   722                     GetTargetDragData(gdkFlavor);

   723                     if (!mTargetDragData) {

   724                         gdkFlavor = gdk_atom_intern(gTextUriListType, FALSE);

   725                         GetTargetDragData(gdkFlavor);

   726                     }

   727                     if (mTargetDragData) {

   728                         const char* text = static_cast<char*>(mTargetDragData);

   729                         char16_t* convertedText = nullptr;

   730                         int32_t convertedTextLen = 0;

   732                         GetTextUriListItem(text, mTargetDragDataLen, aItemIndex,

   733                                            &convertedText, &convertedTextLen);

   735                         if (convertedText) {

   736                             nsCOMPtr<nsIIOService> ioService = do_GetIOService(&rv);

   737                             nsCOMPtr<nsIURI> fileURI;

   738                             nsresult rv = ioService->NewURI(NS_ConvertUTF16toUTF8(convertedText),

   739                                                             nullptr, nullptr, getter_AddRefs(fileURI));

   740                             if (NS_SUCCEEDED(rv)) {

   741                                 nsCOMPtr<nsIFileURL> fileURL = do_QueryInterface(fileURI, &rv);

   742                                 if (NS_SUCCEEDED(rv)) {

   743                                     nsCOMPtr<nsIFile> file;

   744                                     rv = fileURL->GetFile(getter_AddRefs(file));

   745                                     if (NS_SUCCEEDED(rv)) {

   746                                         // The common wrapping code at the end of

   747                                         // this function assumes the data is text

   748                                         // and calls text-specific operations.

   749                                         // Make a secret hideout here for nsIFile

   750                                         // objects and return early.

   751                                         aTransferable->SetTransferData(flavorStr, file,

   752                                                                        convertedTextLen);

   753                                         g_free(convertedText);

   754                                         return NS_OK;

   755                                     }

   756                                 }

   757                             }

   758                             g_free(convertedText);

   759                         }

   760                         continue;

   761                     }

   762                 }

   764                 // if we are looking for text/unicode and we fail to find it

   765                 // on the clipboard first, try again with text/plain. If that

   766                 // is present, convert it to unicode.

   767                 if ( strcmp(flavorStr, kUnicodeMime) == 0 ) {

   768                     PR_LOG(sDragLm, PR_LOG_DEBUG,

   769                            ("we were looking for text/unicode... \

   770                            trying with text/plain;charset=utf-8\n"));

   771                     gdkFlavor = gdk_atom_intern(gTextPlainUTF8Type, FALSE);

   772                     GetTargetDragData(gdkFlavor);

   773                     if (mTargetDragData) {

   774                         PR_LOG(sDragLm, PR_LOG_DEBUG, ("Got textplain data\n"));

   775                         const char* castedText =

   776                                     reinterpret_cast<char*>(mTargetDragData);

   777                         char16_t* convertedText = nullptr;

   778                         NS_ConvertUTF8toUTF16 ucs2string(castedText,

   779                                                          mTargetDragDataLen);

   780                         convertedText = ToNewUnicode(ucs2string);

   781                         if ( convertedText ) {

   782                             PR_LOG(sDragLm, PR_LOG_DEBUG,

   783                                    ("successfully converted plain text \

   784                                    to unicode.\n"));

   785                             // out with the old, in with the new

   786                             g_free(mTargetDragData);

   787                             mTargetDragData = convertedText;

   788                             mTargetDragDataLen = ucs2string.Length() * 2;

   789                             dataFound = true;

   790                         } // if plain text data on clipboard

   791                     } else {

   792                         PR_LOG(sDragLm, PR_LOG_DEBUG,

   793                                ("we were looking for text/unicode... \

   794                                trying again with text/plain\n"));

   795                         gdkFlavor = gdk_atom_intern(kTextMime, FALSE);

   796                         GetTargetDragData(gdkFlavor);

   797                         if (mTargetDragData) {

   798                             PR_LOG(sDragLm, PR_LOG_DEBUG, ("Got textplain data\n"));

   799                             const char* castedText =

   800                                         reinterpret_cast<char*>(mTargetDragData);

   801                             char16_t* convertedText = nullptr;

   802                             int32_t convertedTextLen = 0;

   803                             nsPrimitiveHelpers::ConvertPlatformPlainTextToUnicode(

   804                                                 castedText, mTargetDragDataLen,

   805                                                 &convertedText, &convertedTextLen);

   806                             if ( convertedText ) {

   807                                 PR_LOG(sDragLm, PR_LOG_DEBUG,

   808                                        ("successfully converted plain text \

   809                                        to unicode.\n"));

   810                                 // out with the old, in with the new

   811                                 g_free(mTargetDragData);

   812                                 mTargetDragData = convertedText;

   813                                 mTargetDragDataLen = convertedTextLen * 2;

   814                                 dataFound = true;

   815                             } // if plain text data on clipboard

   816                         } // if plain text flavor present

   817                     } // if plain text charset=utf-8 flavor present

   818                 } // if looking for text/unicode

   820                 // if we are looking for text/x-moz-url and we failed to find

   821                 // it on the clipboard, try again with text/uri-list, and then

   822                 // _NETSCAPE_URL

   823                 if (strcmp(flavorStr, kURLMime) == 0) {

   824                     PR_LOG(sDragLm, PR_LOG_DEBUG,

   825                            ("we were looking for text/x-moz-url...\

   826                            trying again with text/uri-list\n"));

   827                     gdkFlavor = gdk_atom_intern(gTextUriListType, FALSE);

   828                     GetTargetDragData(gdkFlavor);

   829                     if (mTargetDragData) {

   830                         PR_LOG(sDragLm, PR_LOG_DEBUG,

   831                                ("Got text/uri-list data\n"));

   832                         const char *data =

   833                                    reinterpret_cast<char*>(mTargetDragData);

   834                         char16_t* convertedText = nullptr;

   835                         int32_t convertedTextLen = 0;

   837                         GetTextUriListItem(data, mTargetDragDataLen, aItemIndex,

   838                                            &convertedText, &convertedTextLen);

   840                         if ( convertedText ) {

   841                             PR_LOG(sDragLm, PR_LOG_DEBUG,

   842                                    ("successfully converted \

   843                                    _NETSCAPE_URL to unicode.\n"));

   844                             // out with the old, in with the new

   845                             g_free(mTargetDragData);

   846                             mTargetDragData = convertedText;

   847                             mTargetDragDataLen = convertedTextLen * 2;

   848                             dataFound = true;

   849                         }

   850                     }

   851                     else {

   852                         PR_LOG(sDragLm, PR_LOG_DEBUG,

   853                                ("failed to get text/uri-list data\n"));

   854                     }

   855                     if (!dataFound) {

   856                         PR_LOG(sDragLm, PR_LOG_DEBUG,

   857                                ("we were looking for text/x-moz-url...\

   858                                trying again with _NETSCAP_URL\n"));

   859                         gdkFlavor = gdk_atom_intern(gMozUrlType, FALSE);

   860                         GetTargetDragData(gdkFlavor);

   861                         if (mTargetDragData) {

   862                             PR_LOG(sDragLm, PR_LOG_DEBUG,

   863                                    ("Got _NETSCAPE_URL data\n"));

   864                             const char* castedText =

   865                                   reinterpret_cast<char*>(mTargetDragData);

   866                             char16_t* convertedText = nullptr;

   867                             int32_t convertedTextLen = 0;

   868                             nsPrimitiveHelpers::ConvertPlatformPlainTextToUnicode(castedText, mTargetDragDataLen, &convertedText, &convertedTextLen);

   869                             if ( convertedText ) {

   870                                 PR_LOG(sDragLm,

   871                                        PR_LOG_DEBUG,

   872                                        ("successfully converted _NETSCAPE_URL \

   873                                        to unicode.\n"));

   874                                 // out with the old, in with the new

   875                                 g_free(mTargetDragData);

   876                                 mTargetDragData = convertedText;

   877                                 mTargetDragDataLen = convertedTextLen * 2;

   878                                 dataFound = true;

   879                             }

   880                         }

   881                         else {

   882                             PR_LOG(sDragLm, PR_LOG_DEBUG,

   883                                    ("failed to get _NETSCAPE_URL data\n"));

   884                         }

   885                     }

   886                 }

   888             } // else we try one last ditch effort to find our data

   890             if (dataFound) {

   891                 // the DOM only wants LF, so convert from MacOS line endings

   892                 // to DOM line endings.

   893                 nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(

   894                              flavorStr,

   895                              &mTargetDragData,

   896                              reinterpret_cast<int*>(&mTargetDragDataLen));

   898                 // put it into the transferable.

   899                 nsCOMPtr<nsISupports> genericDataWrapper;

   900                 nsPrimitiveHelpers::CreatePrimitiveForData(flavorStr,

   901                                     mTargetDragData, mTargetDragDataLen,

   902                                     getter_AddRefs(genericDataWrapper));

   903                 aTransferable->SetTransferData(flavorStr,

   904                                                genericDataWrapper,

   905                                                mTargetDragDataLen);

   906                 // we found one, get out of this loop!

   907                 PR_LOG(sDragLm, PR_LOG_DEBUG, ("dataFound and converted!\n"));

   908                 break;

   909             }

   910         } // if (currentFlavor)

   911     } // foreach flavor

   913     return NS_OK;

   915 }

   917 NS_IMETHODIMP

   918 nsDragService::IsDataFlavorSupported(const char *aDataFlavor,

   919                                      bool *_retval)

   920 {

   921     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::IsDataFlavorSupported %s",

   922                                    aDataFlavor));

   923     if (!_retval)

   924         return NS_ERROR_INVALID_ARG;

   926     // set this to no by default

   927     *_retval = false;

   929     // check to make sure that we have a drag object set, here

   930     if (!mTargetWidget) {

   931         PR_LOG(sDragLm, PR_LOG_DEBUG,

   932                ("*** warning: IsDataFlavorSupported \

   933                called without a valid target widget!\n"));

   934         return NS_OK;

   935     }

   937     // check to see if the target context is a list.

   938     bool isList = IsTargetContextList();

   939     // if it is, just look in the internal data since we are the source

   940     // for it.

   941     if (isList) {

   942         PR_LOG(sDragLm, PR_LOG_DEBUG, ("It's a list.."));

   943         uint32_t numDragItems = 0;

   944         // if we don't have mDataItems we didn't start this drag so it's

   945         // an external client trying to fool us.

   946         if (!mSourceDataItems)

   947             return NS_OK;

   948         mSourceDataItems->Count(&numDragItems);

   949         for (uint32_t itemIndex = 0; itemIndex < numDragItems; ++itemIndex) {

   950             nsCOMPtr<nsISupports> genericItem;

   951             mSourceDataItems->GetElementAt(itemIndex,

   952                                            getter_AddRefs(genericItem));

   953             nsCOMPtr<nsITransferable> currItem(do_QueryInterface(genericItem));

   954             if (currItem) {

   955                 nsCOMPtr <nsISupportsArray> flavorList;

   956                 currItem->FlavorsTransferableCanExport(

   957                           getter_AddRefs(flavorList));

   958                 if (flavorList) {

   959                     uint32_t numFlavors;

   960                     flavorList->Count( &numFlavors );

   961                     for ( uint32_t flavorIndex = 0;

   962                           flavorIndex < numFlavors ;

   963                           ++flavorIndex ) {

   964                         nsCOMPtr<nsISupports> genericWrapper;

   965                         flavorList->GetElementAt(flavorIndex,

   966                                                 getter_AddRefs(genericWrapper));

   967                         nsCOMPtr<nsISupportsCString> currentFlavor;

   968                         currentFlavor = do_QueryInterface(genericWrapper);

   969                         if (currentFlavor) {

   970                             nsXPIDLCString flavorStr;

   971                             currentFlavor->ToString(getter_Copies(flavorStr));

   972                             PR_LOG(sDragLm, PR_LOG_DEBUG,

   973                                    ("checking %s against %s\n",

   974                                    (const char *)flavorStr, aDataFlavor));

   975                             if (strcmp(flavorStr, aDataFlavor) == 0) {

   976                                 PR_LOG(sDragLm, PR_LOG_DEBUG,

   977                                        ("boioioioiooioioioing!\n"));

   978                                 *_retval = true;

   979                             }

   980                         }

   981                     }

   982                 }

   983             }

   984         }

   985         return NS_OK;

   986     }

   988     // check the target context vs. this flavor, one at a time

   989     GList *tmp;

   990     for (tmp = gdk_drag_context_list_targets(mTargetDragContext);

   991          tmp; tmp = tmp->next) {

   992         /* Bug 331198 */

   993         GdkAtom atom = GDK_POINTER_TO_ATOM(tmp->data);

   994         gchar *name = nullptr;

   995         name = gdk_atom_name(atom);

   996         PR_LOG(sDragLm, PR_LOG_DEBUG,

   997                ("checking %s against %s\n", name, aDataFlavor));

   998         if (name && (strcmp(name, aDataFlavor) == 0)) {

   999             PR_LOG(sDragLm, PR_LOG_DEBUG, ("good!\n"));

  1000             *_retval = true;

  1001         }

  1002         // check for automatic text/uri-list -> text/x-moz-url mapping

  1003         if (!*_retval &&

  1004             name &&

  1005             (strcmp(name, gTextUriListType) == 0) &&

  1006             (strcmp(aDataFlavor, kURLMime) == 0 ||

  1007              strcmp(aDataFlavor, kFileMime) == 0)) {

  1008             PR_LOG(sDragLm, PR_LOG_DEBUG,

  1009                    ("good! ( it's text/uri-list and \

  1010                    we're checking against text/x-moz-url )\n"));

  1011             *_retval = true;

  1012         }

  1013         // check for automatic _NETSCAPE_URL -> text/x-moz-url mapping

  1014         if (!*_retval &&

  1015             name &&

  1016             (strcmp(name, gMozUrlType) == 0) &&

  1017             (strcmp(aDataFlavor, kURLMime) == 0)) {

  1018             PR_LOG(sDragLm, PR_LOG_DEBUG,

  1019                    ("good! ( it's _NETSCAPE_URL and \

  1020                    we're checking against text/x-moz-url )\n"));

  1021             *_retval = true;

  1022         }

  1023         // check for auto text/plain -> text/unicode mapping

  1024         if (!*_retval &&

  1025             name &&

  1026             (strcmp(name, kTextMime) == 0) &&

  1027             ((strcmp(aDataFlavor, kUnicodeMime) == 0) ||

  1028              (strcmp(aDataFlavor, kFileMime) == 0))) {

  1029             PR_LOG(sDragLm, PR_LOG_DEBUG,

  1030                    ("good! ( it's text plain and we're checking \

  1031                    against text/unicode or application/x-moz-file)\n"));

  1032             *_retval = true;

  1033         }

  1034         g_free(name);

  1035     }

  1036     return NS_OK;

  1037 }

  1039 void

  1040 nsDragService::ReplyToDragMotion()

  1041 {

  1042     PR_LOG(sDragLm, PR_LOG_DEBUG,

  1043            ("nsDragService::ReplyToDragMotion %d", mCanDrop));

  1045     GdkDragAction action = (GdkDragAction)0;

  1046     if (mCanDrop) {

  1047         // notify the dragger if we can drop

  1048         switch (mDragAction) {

  1049         case DRAGDROP_ACTION_COPY:

  1050           action = GDK_ACTION_COPY;

  1051           break;

  1052         case DRAGDROP_ACTION_LINK:

  1053           action = GDK_ACTION_LINK;

  1054           break;

  1055         default:

  1056           action = GDK_ACTION_MOVE;

  1057           break;

  1058         }

  1059     }

  1061     gdk_drag_status(mTargetDragContext, action, mTargetTime);

  1062 }

  1064 void

  1065 nsDragService::TargetDataReceived(GtkWidget         *aWidget,

  1066                                   GdkDragContext    *aContext,

  1067                                   gint               aX,

  1068                                   gint               aY,

  1069                                   GtkSelectionData  *aSelectionData,

  1070                                   guint              aInfo,

  1071                                   guint32            aTime)

  1072 {

  1073     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::TargetDataReceived"));

  1074     TargetResetData();

  1075     mTargetDragDataReceived = true;

  1076     gint len = gtk_selection_data_get_length(aSelectionData);

  1077     const guchar* data = gtk_selection_data_get_data(aSelectionData);

  1078     if (len > 0 && data) {

  1079         mTargetDragDataLen = len;

  1080         mTargetDragData = g_malloc(mTargetDragDataLen);

  1081         memcpy(mTargetDragData, data, mTargetDragDataLen);

  1082     }

  1083     else {

  1084         PR_LOG(sDragLm, PR_LOG_DEBUG,

  1085                ("Failed to get data.  selection data len was %d\n",

  1086                 mTargetDragDataLen));

  1087     }

  1088 }

  1090 bool

  1091 nsDragService::IsTargetContextList(void)

  1092 {

  1093     bool retval = false;

  1095     // gMimeListType drags only work for drags within a single process. The

  1096     // gtk_drag_get_source_widget() function will return nullptr if the source

  1097     // of the drag is another app, so we use it to check if a gMimeListType

  1098     // drop will work or not.

  1099     if (gtk_drag_get_source_widget(mTargetDragContext) == nullptr)

  1100         return retval;

  1102     GList *tmp;

  1104     // walk the list of context targets and see if one of them is a list

  1105     // of items.

  1106     for (tmp = gdk_drag_context_list_targets(mTargetDragContext);

  1107          tmp; tmp = tmp->next) {

  1108         /* Bug 331198 */

  1109         GdkAtom atom = GDK_POINTER_TO_ATOM(tmp->data);

  1110         gchar *name = nullptr;

  1111         name = gdk_atom_name(atom);

  1112         if (name && strcmp(name, gMimeListType) == 0)

  1113             retval = true;

  1114         g_free(name);

  1115         if (retval)

  1116             break;

  1117     }

  1118     return retval;

  1119 }

  1121 // Maximum time to wait for a "drag_received" arrived, in microseconds

  1122 #define NS_DND_TIMEOUT 500000

  1124 void

  1125 nsDragService::GetTargetDragData(GdkAtom aFlavor)

  1126 {

  1127     PR_LOG(sDragLm, PR_LOG_DEBUG, ("getting data flavor %d\n", aFlavor));

  1128     PR_LOG(sDragLm, PR_LOG_DEBUG, ("mLastWidget is %p and mLastContext is %p\n",

  1129                                    mTargetWidget.get(),

  1130                                    mTargetDragContext.get()));

  1131     // reset our target data areas

  1132     TargetResetData();

  1133     gtk_drag_get_data(mTargetWidget, mTargetDragContext, aFlavor, mTargetTime);

  1135     PR_LOG(sDragLm, PR_LOG_DEBUG, ("about to start inner iteration."));

  1136     PRTime entryTime = PR_Now();

  1137     while (!mTargetDragDataReceived && mDoingDrag) {

  1138         // check the number of iterations

  1139         PR_LOG(sDragLm, PR_LOG_DEBUG, ("doing iteration...\n"));

  1140         PR_Sleep(20*PR_TicksPerSecond()/1000);  /* sleep for 20 ms/iteration */

  1141         if (PR_Now()-entryTime > NS_DND_TIMEOUT) break;

  1142         gtk_main_iteration();

  1143     }

  1144     PR_LOG(sDragLm, PR_LOG_DEBUG, ("finished inner iteration\n"));

  1145 }

  1147 void

  1148 nsDragService::TargetResetData(void)

  1149 {

  1150     mTargetDragDataReceived = false;

  1151     // make sure to free old data if we have to

  1152     g_free(mTargetDragData);

  1153     mTargetDragData = 0;

  1154     mTargetDragDataLen = 0;

  1155 }

  1157 GtkTargetList *

  1158 nsDragService::GetSourceList(void)

  1159 {

  1160     if (!mSourceDataItems)

  1161         return nullptr;

  1162     nsTArray<GtkTargetEntry*> targetArray;

  1163     GtkTargetEntry *targets;

  1164     GtkTargetList  *targetList = 0;

  1165     uint32_t targetCount = 0;

  1166     unsigned int numDragItems = 0;

  1168     mSourceDataItems->Count(&numDragItems);

  1170     // Check to see if we're dragging > 1 item.

  1171     if (numDragItems > 1) {

  1172         // as the Xdnd protocol only supports a single item (or is it just

  1173         // gtk's implementation?), we don't advertise all flavours listed

  1174         // in the nsITransferable.

  1176         // the application/x-moz-internal-item-list format, which preserves

  1177         // all information for drags within the same mozilla instance.

  1178         GtkTargetEntry *listTarget =

  1179             (GtkTargetEntry *)g_malloc(sizeof(GtkTargetEntry));

  1180         listTarget->target = g_strdup(gMimeListType);

  1181         listTarget->flags = 0;

  1182         PR_LOG(sDragLm, PR_LOG_DEBUG,

  1183                ("automatically adding target %s\n", listTarget->target));

  1184         targetArray.AppendElement(listTarget);

  1186         // check what flavours are supported so we can decide what other

  1187         // targets to advertise.

  1188         nsCOMPtr<nsISupports> genericItem;

  1189         mSourceDataItems->GetElementAt(0, getter_AddRefs(genericItem));

  1190         nsCOMPtr<nsITransferable> currItem(do_QueryInterface(genericItem));

  1192         if (currItem) {

  1193             nsCOMPtr <nsISupportsArray> flavorList;

  1194             currItem->FlavorsTransferableCanExport(getter_AddRefs(flavorList));

  1195             if (flavorList) {

  1196                 uint32_t numFlavors;

  1197                 flavorList->Count( &numFlavors );

  1198                 for (uint32_t flavorIndex = 0;

  1199                      flavorIndex < numFlavors ;

  1200                      ++flavorIndex ) {

  1201                     nsCOMPtr<nsISupports> genericWrapper;

  1202                     flavorList->GetElementAt(flavorIndex,

  1203                                            getter_AddRefs(genericWrapper));

  1204                     nsCOMPtr<nsISupportsCString> currentFlavor;

  1205                     currentFlavor = do_QueryInterface(genericWrapper);

  1206                     if (currentFlavor) {

  1207                         nsXPIDLCString flavorStr;

  1208                         currentFlavor->ToString(getter_Copies(flavorStr));

  1210                         // check if text/x-moz-url is supported.

  1211                         // If so, advertise

  1212                         // text/uri-list.

  1213                         if (strcmp(flavorStr, kURLMime) == 0) {

  1214                             listTarget =

  1215                              (GtkTargetEntry *)g_malloc(sizeof(GtkTargetEntry));

  1216                             listTarget->target = g_strdup(gTextUriListType);

  1217                             listTarget->flags = 0;

  1218                             PR_LOG(sDragLm, PR_LOG_DEBUG,

  1219                                    ("automatically adding target %s\n",

  1220                                     listTarget->target));

  1221                             targetArray.AppendElement(listTarget);

  1222                         }

  1223                     }

  1224                 } // foreach flavor in item

  1225             } // if valid flavor list

  1226         } // if item is a transferable

  1227     } else if (numDragItems == 1) {

  1228         nsCOMPtr<nsISupports> genericItem;

  1229         mSourceDataItems->GetElementAt(0, getter_AddRefs(genericItem));

  1230         nsCOMPtr<nsITransferable> currItem(do_QueryInterface(genericItem));

  1231         if (currItem) {

  1232             nsCOMPtr <nsISupportsArray> flavorList;

  1233             currItem->FlavorsTransferableCanExport(getter_AddRefs(flavorList));

  1234             if (flavorList) {

  1235                 uint32_t numFlavors;

  1236                 flavorList->Count( &numFlavors );

  1237                 for (uint32_t flavorIndex = 0;

  1238                      flavorIndex < numFlavors ;

  1239                      ++flavorIndex ) {

  1240                     nsCOMPtr<nsISupports> genericWrapper;

  1241                     flavorList->GetElementAt(flavorIndex,

  1242                                              getter_AddRefs(genericWrapper));

  1243                     nsCOMPtr<nsISupportsCString> currentFlavor;

  1244                     currentFlavor = do_QueryInterface(genericWrapper);

  1245                     if (currentFlavor) {

  1246                         nsXPIDLCString flavorStr;

  1247                         currentFlavor->ToString(getter_Copies(flavorStr));

  1248                         GtkTargetEntry *target =

  1249                           (GtkTargetEntry *)g_malloc(sizeof(GtkTargetEntry));

  1250                         target->target = g_strdup(flavorStr);

  1251                         target->flags = 0;

  1252                         PR_LOG(sDragLm, PR_LOG_DEBUG,

  1253                                ("adding target %s\n", target->target));

  1254                         targetArray.AppendElement(target);

  1255                         // Check to see if this is text/unicode.

  1256                         // If it is, add text/plain

  1257                         // since we automatically support text/plain

  1258                         // if we support text/unicode.

  1259                         if (strcmp(flavorStr, kUnicodeMime) == 0) {

  1260                             GtkTargetEntry *plainUTF8Target =

  1261                              (GtkTargetEntry *)g_malloc(sizeof(GtkTargetEntry));

  1262                             plainUTF8Target->target = g_strdup(gTextPlainUTF8Type);

  1263                             plainUTF8Target->flags = 0;

  1264                             PR_LOG(sDragLm, PR_LOG_DEBUG,

  1265                                    ("automatically adding target %s\n",

  1266                                     plainUTF8Target->target));

  1267                             targetArray.AppendElement(plainUTF8Target);

  1269                             GtkTargetEntry *plainTarget =

  1270                              (GtkTargetEntry *)g_malloc(sizeof(GtkTargetEntry));

  1271                             plainTarget->target = g_strdup(kTextMime);

  1272                             plainTarget->flags = 0;

  1273                             PR_LOG(sDragLm, PR_LOG_DEBUG,

  1274                                    ("automatically adding target %s\n",

  1275                                     plainTarget->target));

  1276                             targetArray.AppendElement(plainTarget);

  1277                         }

  1278                         // Check to see if this is the x-moz-url type.

  1279                         // If it is, add _NETSCAPE_URL

  1280                         // this is a type used by everybody.

  1281                         if (strcmp(flavorStr, kURLMime) == 0) {

  1282                             GtkTargetEntry *urlTarget =

  1283                              (GtkTargetEntry *)g_malloc(sizeof(GtkTargetEntry));

  1284                             urlTarget->target = g_strdup(gMozUrlType);

  1285                             urlTarget->flags = 0;

  1286                             PR_LOG(sDragLm, PR_LOG_DEBUG,

  1287                                    ("automatically adding target %s\n",

  1288                                     urlTarget->target));

  1289                             targetArray.AppendElement(urlTarget);

  1290                         }

  1291                     }

  1292                 } // foreach flavor in item

  1293             } // if valid flavor list

  1294         } // if item is a transferable

  1295     } // if it is a single item drag

  1297     // get all the elements that we created.

  1298     targetCount = targetArray.Length();

  1299     if (targetCount) {

  1300         // allocate space to create the list of valid targets

  1301         targets =

  1302           (GtkTargetEntry *)g_malloc(sizeof(GtkTargetEntry) * targetCount);

  1303         uint32_t targetIndex;

  1304         for ( targetIndex = 0; targetIndex < targetCount; ++targetIndex) {

  1305             GtkTargetEntry *disEntry = targetArray.ElementAt(targetIndex);

  1306             // this is a string reference but it will be freed later.

  1307             targets[targetIndex].target = disEntry->target;

  1308             targets[targetIndex].flags = disEntry->flags;

  1309             targets[targetIndex].info = 0;

  1310         }

  1311         targetList = gtk_target_list_new(targets, targetCount);

  1312         // clean up the target list

  1313         for (uint32_t cleanIndex = 0; cleanIndex < targetCount; ++cleanIndex) {

  1314             GtkTargetEntry *thisTarget = targetArray.ElementAt(cleanIndex);

  1315             g_free(thisTarget->target);

  1316             g_free(thisTarget);

  1317         }

  1318         g_free(targets);

  1319     }

  1320     return targetList;

  1321 }

  1323 void

  1324 nsDragService::SourceEndDragSession(GdkDragContext *aContext,

  1325                                     gint            aResult)

  1326 {

  1327     // this just releases the list of data items that we provide

  1328     mSourceDataItems = nullptr;

  1330     if (!mDoingDrag || mScheduledTask == eDragTaskSourceEnd)

  1331         // EndDragSession() was already called on drop

  1332         // or SourceEndDragSession on drag-failed

  1333         return;

  1335     if (mEndDragPoint.x < 0) {

  1336         // We don't have a drag end point, so guess

  1337         gint x, y;

  1338         GdkDisplay* display = gdk_display_get_default();

  1339         if (display) {

  1340             gdk_display_get_pointer(display, nullptr, &x, &y, nullptr);

  1341             SetDragEndPoint(nsIntPoint(x, y));

  1342         }

  1343     }

  1345     // Either the drag was aborted or the drop occurred outside the app.

  1346     // The dropEffect of mDataTransfer is not updated for motion outside the

  1347     // app, but is needed for the dragend event, so set it now.

  1349     uint32_t dropEffect;

  1351     if (aResult == MOZ_GTK_DRAG_RESULT_SUCCESS) {

  1353         // With GTK+ versions 2.10.x and prior the drag may have been

  1354         // cancelled (but no drag-failed signal would have been sent).

  1355         // aContext->dest_window will be non-nullptr only if the drop was

  1356         // sent.

  1357         GdkDragAction action =

  1358             gdk_drag_context_get_dest_window(aContext) ?

  1359                 gdk_drag_context_get_actions(aContext) : (GdkDragAction)0;

  1361         // Only one bit of action should be set, but, just in case someone

  1362         // does something funny, erring away from MOVE, and not recording

  1363         // unusual action combinations as NONE.

  1364         if (!action)

  1365             dropEffect = DRAGDROP_ACTION_NONE;

  1366         else if (action & GDK_ACTION_COPY)

  1367             dropEffect = DRAGDROP_ACTION_COPY;

  1368         else if (action & GDK_ACTION_LINK)

  1369             dropEffect = DRAGDROP_ACTION_LINK;

  1370         else if (action & GDK_ACTION_MOVE)

  1371             dropEffect = DRAGDROP_ACTION_MOVE;

  1372         else

  1373             dropEffect = DRAGDROP_ACTION_COPY;

  1375     } else {

  1377         dropEffect = DRAGDROP_ACTION_NONE;

  1379         if (aResult != MOZ_GTK_DRAG_RESULT_NO_TARGET) {

  1380             mUserCancelled = true;

  1381         }

  1382     }

  1384     if (mDataTransfer) {

  1385         mDataTransfer->SetDropEffectInt(dropEffect);

  1386     }

  1388     // Schedule the appropriate drag end dom events.

  1389     Schedule(eDragTaskSourceEnd, nullptr, nullptr, nsIntPoint(), 0);

  1390 }

  1392 static void

  1393 CreateUriList(nsISupportsArray *items, gchar **text, gint *length)

  1394 {

  1395     uint32_t i, count;

  1396     GString *uriList = g_string_new(nullptr);

  1398     items->Count(&count);

  1399     for (i = 0; i < count; i++) {

  1400         nsCOMPtr<nsISupports> genericItem;

  1401         items->GetElementAt(i, getter_AddRefs(genericItem));

  1402         nsCOMPtr<nsITransferable> item;

  1403         item = do_QueryInterface(genericItem);

  1405         if (item) {

  1406             uint32_t tmpDataLen = 0;

  1407             void    *tmpData = nullptr;

  1408             nsresult rv = NS_OK;

  1409             nsCOMPtr<nsISupports> data;

  1410             rv = item->GetTransferData(kURLMime,

  1411                                        getter_AddRefs(data),

  1412                                        &tmpDataLen);

  1414             if (NS_SUCCEEDED(rv)) {

  1415                 nsPrimitiveHelpers::CreateDataFromPrimitive(kURLMime,

  1416                                                             data,

  1417                                                             &tmpData,

  1418                                                             tmpDataLen);

  1419                 char* plainTextData = nullptr;

  1420                 char16_t* castedUnicode = reinterpret_cast<char16_t*>

  1421                                                            (tmpData);

  1422                 int32_t plainTextLen = 0;

  1423                 nsPrimitiveHelpers::ConvertUnicodeToPlatformPlainText(

  1424                                     castedUnicode,

  1425                                     tmpDataLen / 2,

  1426                                     &plainTextData,

  1427                                     &plainTextLen);

  1428                 if (plainTextData) {

  1429                     int32_t j;

  1431                     // text/x-moz-url is of form url + "\n" + title.

  1432                     // We just want the url.

  1433                     for (j = 0; j < plainTextLen; j++)

  1434                         if (plainTextData[j] == '\n' ||

  1435                             plainTextData[j] == '\r') {

  1436                             plainTextData[j] = '\0';

  1437                             break;

  1438                         }

  1439                     g_string_append(uriList, plainTextData);

  1440                     g_string_append(uriList, "\r\n");

  1441                     // this wasn't allocated with glib

  1442                     free(plainTextData);

  1443                 }

  1444                 if (tmpData) {

  1445                     // this wasn't allocated with glib

  1446                     free(tmpData);

  1447                 }

  1448             }

  1449         }

  1450     }

  1451     *text = uriList->str;

  1452     *length = uriList->len + 1;

  1453     g_string_free(uriList, FALSE); // don't free the data

  1454 }

  1457 void

  1458 nsDragService::SourceDataGet(GtkWidget        *aWidget,

  1459                              GdkDragContext   *aContext,

  1460                              GtkSelectionData *aSelectionData,

  1461                              guint32           aTime)

  1462 {

  1463     PR_LOG(sDragLm, PR_LOG_DEBUG, ("nsDragService::SourceDataGet"));

  1464     GdkAtom target = gtk_selection_data_get_target(aSelectionData);

  1465     nsXPIDLCString mimeFlavor;

  1466     gchar *typeName = 0;

  1467     typeName = gdk_atom_name(target);

  1468     if (!typeName) {

  1469         PR_LOG(sDragLm, PR_LOG_DEBUG, ("failed to get atom name.\n"));

  1470         return;

  1471     }

  1473     PR_LOG(sDragLm, PR_LOG_DEBUG, ("Type is %s\n", typeName));

  1474     // make a copy since |nsXPIDLCString| won't use |g_free|...

  1475     mimeFlavor.Adopt(strdup(typeName));

  1476     g_free(typeName);

  1477     // check to make sure that we have data items to return.

  1478     if (!mSourceDataItems) {

  1479         PR_LOG(sDragLm, PR_LOG_DEBUG, ("Failed to get our data items\n"));

  1480         return;

  1481     }

  1483     nsCOMPtr<nsISupports> genericItem;

  1484     mSourceDataItems->GetElementAt(0, getter_AddRefs(genericItem));

  1485     nsCOMPtr<nsITransferable> item;

  1486     item = do_QueryInterface(genericItem);

  1487     if (item) {

  1488         // if someone was asking for text/plain, lookup unicode instead so

  1489         // we can convert it.

  1490         bool needToDoConversionToPlainText = false;

  1491         const char* actualFlavor = mimeFlavor;

  1492         if (strcmp(mimeFlavor, kTextMime) == 0 ||

  1493             strcmp(mimeFlavor, gTextPlainUTF8Type) == 0) {

  1494             actualFlavor = kUnicodeMime;

  1495             needToDoConversionToPlainText = true;

  1496         }

  1497         // if someone was asking for _NETSCAPE_URL we need to convert to

  1498         // plain text but we also need to look for x-moz-url

  1499         else if (strcmp(mimeFlavor, gMozUrlType) == 0) {

  1500             actualFlavor = kURLMime;

  1501             needToDoConversionToPlainText = true;

  1502         }

  1503         // if someone was asking for text/uri-list we need to convert to

  1504         // plain text.

  1505         else if (strcmp(mimeFlavor, gTextUriListType) == 0) {

  1506             actualFlavor = gTextUriListType;

  1507             needToDoConversionToPlainText = true;

  1508         }

  1509         else

  1510             actualFlavor = mimeFlavor;

  1512         uint32_t tmpDataLen = 0;

  1513         void    *tmpData = nullptr;

  1514         nsresult rv;

  1515         nsCOMPtr<nsISupports> data;

  1516         rv = item->GetTransferData(actualFlavor,

  1517                                    getter_AddRefs(data),

  1518                                    &tmpDataLen);

  1519         if (NS_SUCCEEDED(rv)) {

  1520             nsPrimitiveHelpers::CreateDataFromPrimitive (actualFlavor, data,

  1521                                                          &tmpData, tmpDataLen);

  1522             // if required, do the extra work to convert unicode to plain

  1523             // text and replace the output values with the plain text.

  1524             if (needToDoConversionToPlainText) {

  1525                 char* plainTextData = nullptr;

  1526                 char16_t* castedUnicode = reinterpret_cast<char16_t*>

  1527                                                            (tmpData);

  1528                 int32_t plainTextLen = 0;

  1529                 if (strcmp(mimeFlavor, gTextPlainUTF8Type) == 0) {

  1530                     plainTextData =

  1531                         ToNewUTF8String(

  1532                             nsDependentString(castedUnicode, tmpDataLen / 2),

  1533                             (uint32_t*)&plainTextLen);

  1534                 } else {

  1535                     nsPrimitiveHelpers::ConvertUnicodeToPlatformPlainText(

  1536                                         castedUnicode,

  1537                                         tmpDataLen / 2,

  1538                                         &plainTextData,

  1539                                         &plainTextLen);

  1540                 }

  1541                 if (tmpData) {

  1542                     // this was not allocated using glib

  1543                     free(tmpData);

  1544                     tmpData = plainTextData;

  1545                     tmpDataLen = plainTextLen;

  1546                 }

  1547             }

  1548             if (tmpData) {

  1549                 // this copies the data

  1550                 gtk_selection_data_set(aSelectionData, target,

  1551                                        8,

  1552                                        (guchar *)tmpData, tmpDataLen);

  1553                 // this wasn't allocated with glib

  1554                 free(tmpData);

  1555             }

  1556         } else {

  1557             if (strcmp(mimeFlavor, gTextUriListType) == 0) {

  1558                 // fall back for text/uri-list

  1559                 gchar *uriList;

  1560                 gint length;

  1561                 CreateUriList(mSourceDataItems, &uriList, &length);

  1562                 gtk_selection_data_set(aSelectionData, target,

  1563                                        8, (guchar *)uriList, length);

  1564                 g_free(uriList);

  1565                 return;

  1566             }

  1567         }

  1568     }

  1569 }

  1571 void nsDragService::SetDragIcon(GdkDragContext* aContext)

  1572 {

  1573     if (!mHasImage && !mSelection)

  1574         return;

  1576     nsIntRect dragRect;

  1577     nsPresContext* pc;

  1578     RefPtr<SourceSurface> surface;

  1579     DrawDrag(mSourceNode, mSourceRegion, mScreenX, mScreenY,

  1580              &dragRect, &surface, &pc);

  1581     if (!pc)

  1582         return;

  1584     int32_t sx = mScreenX, sy = mScreenY;

  1585     ConvertToUnscaledDevPixels(pc, &sx, &sy);

  1587     int32_t offsetX = sx - dragRect.x;

  1588     int32_t offsetY = sy - dragRect.y;

  1590     // If a popup is set as the drag image, use its widget. Otherwise, use

  1591     // the surface that DrawDrag created.

  1592     if (mDragPopup) {

  1593         GtkWidget* gtkWidget = nullptr;

  1594         nsIFrame* frame = mDragPopup->GetPrimaryFrame();

  1595         if (frame) {

  1596             // DrawDrag ensured that this is a popup frame.

  1597             nsCOMPtr<nsIWidget> widget = frame->GetNearestWidget();

  1598             if (widget) {

  1599                 gtkWidget = (GtkWidget *)widget->GetNativeData(NS_NATIVE_SHELLWIDGET);

  1600                 if (gtkWidget) {

  1601                     OpenDragPopup();

  1602                     gtk_drag_set_icon_widget(aContext, gtkWidget, offsetX, offsetY);

  1603                 }

  1604             }

  1605         }

  1606     }

  1607     else if (surface) {

  1608         if (!SetAlphaPixmap(surface, aContext, offsetX, offsetY, dragRect)) {

  1609             GdkPixbuf* dragPixbuf =

  1610               nsImageToPixbuf::SourceSurfaceToPixbuf(surface, dragRect.width, dragRect.height);

  1611             if (dragPixbuf) {

  1612                 gtk_drag_set_icon_pixbuf(aContext, dragPixbuf, offsetX, offsetY);

  1613                 g_object_unref(dragPixbuf);

  1614             }

  1615         }

  1616     }

  1617 }

  1619 static void

  1620 invisibleSourceDragBegin(GtkWidget        *aWidget,

  1621                          GdkDragContext   *aContext,

  1622                          gpointer          aData)

  1623 {

  1624     PR_LOG(sDragLm, PR_LOG_DEBUG, ("invisibleSourceDragBegin"));

  1625     nsDragService *dragService = (nsDragService *)aData;

  1627     dragService->SetDragIcon(aContext);

  1628 }

  1630 static void

  1631 invisibleSourceDragDataGet(GtkWidget        *aWidget,

  1632                            GdkDragContext   *aContext,

  1633                            GtkSelectionData *aSelectionData,

  1634                            guint             aInfo,

  1635                            guint32           aTime,

  1636                            gpointer          aData)

  1637 {

  1638     PR_LOG(sDragLm, PR_LOG_DEBUG, ("invisibleSourceDragDataGet"));

  1639     nsDragService *dragService = (nsDragService *)aData;

  1640     dragService->SourceDataGet(aWidget, aContext,

  1641                                aSelectionData, aTime);

  1642 }

  1644 static gboolean

  1645 invisibleSourceDragFailed(GtkWidget        *aWidget,

  1646                           GdkDragContext   *aContext,

  1647                           gint              aResult,

  1648                           gpointer          aData)

  1649 {

  1650     PR_LOG(sDragLm, PR_LOG_DEBUG, ("invisibleSourceDragFailed %i", aResult));

  1651     nsDragService *dragService = (nsDragService *)aData;

  1652     // End the drag session now (rather than waiting for the drag-end signal)

  1653     // so that operations performed on dropEffect == none can start immediately

  1654     // rather than waiting for the drag-failed animation to finish.

  1655     dragService->SourceEndDragSession(aContext, aResult);

  1657     // We should return TRUE to disable the drag-failed animation iff the

  1658     // source performed an operation when dropEffect was none, but the handler

  1659     // of the dragend DOM event doesn't provide this information.

  1660     return FALSE;

  1661 }

  1663 static void

  1664 invisibleSourceDragEnd(GtkWidget        *aWidget,

  1665                        GdkDragContext   *aContext,

  1666                        gpointer          aData)

  1667 {

  1668     PR_LOG(sDragLm, PR_LOG_DEBUG, ("invisibleSourceDragEnd"));

  1669     nsDragService *dragService = (nsDragService *)aData;

  1671     // The drag has ended.  Release the hostages!

  1672     dragService->SourceEndDragSession(aContext, MOZ_GTK_DRAG_RESULT_SUCCESS);

  1673 }

  1675 // The following methods handle responding to GTK drag signals and

  1676 // tracking state between these signals.

  1677 //

  1678 // In general, GTK does not expect us to run the event loop while handling its

  1679 // drag signals, however our drag event handlers may run the

  1680 // event loop, most often to fetch information about the drag data.

  1681 //

  1682 // GTK, for example, uses the return value from drag-motion signals to

  1683 // determine whether drag-leave signals should be sent.  If an event loop is

  1684 // run during drag-motion the XdndLeave message can get processed but when GTK

  1685 // receives the message it does not yet know that it needs to send the

  1686 // drag-leave signal to our widget.

  1687 //

  1688 // After a drag-drop signal, we need to reply with gtk_drag_finish().

  1689 // However, gtk_drag_finish should happen after the drag-drop signal handler

  1690 // returns so that when the Motif drag protocol is used, the

  1691 // XmTRANSFER_SUCCESS during gtk_drag_finish is sent after the XmDROP_START

  1692 // reply sent on return from the drag-drop signal handler.

  1693 //

  1694 // Similarly drag-end for a successful drag and drag-failed are not good

  1695 // times to run a nested event loop as gtk_drag_drop_finished() and

  1696 // gtk_drag_source_info_destroy() don't gtk_drag_clear_source_info() or remove

  1697 // drop_timeout until after at least the first of these signals is sent.

  1698 // Processing other events (e.g. a slow GDK_DROP_FINISHED reply, or the drop

  1699 // timeout) could cause gtk_drag_drop_finished to be called again with the

  1700 // same GtkDragSourceInfo, which won't like being destroyed twice.

  1701 //

  1702 // Therefore we reply to the signals immediately and schedule a task to

  1703 // dispatch the Gecko events, which may run the event loop.

  1704 //

  1705 // Action in response to drag-leave signals is also delayed until the event

  1706 // loop runs again so that we find out whether a drag-drop signal follows.

  1707 //

  1708 // A single task is scheduled to manage responses to all three GTK signals.

  1709 // If further signals are received while the task is scheduled, the scheduled

  1710 // response is updated, sometimes effectively compressing successive signals.

  1711 //

  1712 // No Gecko drag events are dispatched (during nested event loops) while other

  1713 // Gecko drag events are in flight.  This helps event handlers that may not

  1714 // expect nested events, while accessing an event's dataTransfer for example.

  1716 gboolean

  1717 nsDragService::ScheduleMotionEvent(nsWindow *aWindow,

  1718                                    GdkDragContext *aDragContext,

  1719                                    nsIntPoint aWindowPoint, guint aTime)

  1720 {

  1721     if (mScheduledTask == eDragTaskMotion) {

  1722         // The drag source has sent another motion message before we've

  1723         // replied to the previous.  That shouldn't happen with Xdnd.  The

  1724         // spec for Motif drags is less clear, but we'll just update the

  1725         // scheduled task with the new position reply only to the most

  1726         // recent message.

  1727         NS_WARNING("Drag Motion message received before previous reply was sent");

  1728     }

  1730     // Returning TRUE means we'll reply with a status message, unless we first

  1731     // get a leave.

  1732     return Schedule(eDragTaskMotion, aWindow, aDragContext,

  1733                     aWindowPoint, aTime);

  1734 }

  1736 void

  1737 nsDragService::ScheduleLeaveEvent()

  1738 {

  1739     // We don't know at this stage whether a drop signal will immediately

  1740     // follow.  If the drop signal gets sent it will happen before we return

  1741     // to the main loop and the scheduled leave task will be replaced.

  1742     if (!Schedule(eDragTaskLeave, nullptr, nullptr, nsIntPoint(), 0)) {

  1743         NS_WARNING("Drag leave after drop");

  1744     }

  1745 }

  1747 gboolean

  1748 nsDragService::ScheduleDropEvent(nsWindow *aWindow,

  1749                                  GdkDragContext *aDragContext,

  1750                                  nsIntPoint aWindowPoint, guint aTime)

  1751 {

  1752     if (!Schedule(eDragTaskDrop, aWindow,

  1753                   aDragContext, aWindowPoint, aTime)) {

  1754         NS_WARNING("Additional drag drop ignored");

  1755         return FALSE;

  1756     }

  1758     SetDragEndPoint(aWindowPoint + aWindow->WidgetToScreenOffset());

  1760     // We'll reply with gtk_drag_finish().

  1761     return TRUE;

  1762 }

  1764 gboolean

  1765 nsDragService::Schedule(DragTask aTask, nsWindow *aWindow,

  1766                         GdkDragContext *aDragContext,

  1767                         nsIntPoint aWindowPoint, guint aTime)

  1768 {

  1769     // If there is an existing leave or motion task scheduled, then that

  1770     // will be replaced.  When the new task is run, it will dispatch

  1771     // any necessary leave or motion events.

  1773     // If aTask is eDragTaskSourceEnd, then it will replace even a scheduled

  1774     // drop event (which could happen if the drop event has not been processed

  1775     // within the allowed time).  Otherwise, if we haven't yet run a scheduled

  1776     // drop or end task, just say that we are not ready to receive another

  1777     // drop.

  1778     if (mScheduledTask == eDragTaskSourceEnd ||

  1779         (mScheduledTask == eDragTaskDrop && aTask != eDragTaskSourceEnd))

  1780         return FALSE;

  1782     mScheduledTask = aTask;

  1783     mPendingWindow = aWindow;

  1784     mPendingDragContext = aDragContext;

  1785     mPendingWindowPoint = aWindowPoint;

  1786     mPendingTime = aTime;

  1788     if (!mTaskSource) {

  1789         // High priority is used here because the native events involved have

  1790         // already waited at default priority.  Perhaps a lower than default

  1791         // priority could be used for motion tasks because there is a chance

  1792         // that a leave or drop is waiting, but managing different priorities

  1793         // may not be worth the effort.  Motion tasks shouldn't queue up as

  1794         // they should be throttled based on replies.

  1795         mTaskSource = g_idle_add_full(G_PRIORITY_HIGH, TaskDispatchCallback,

  1796                                       this, nullptr);

  1797     }

  1798     return TRUE;

  1799 }

  1801 gboolean

  1802 nsDragService::TaskDispatchCallback(gpointer data)

  1803 {

  1804     nsRefPtr<nsDragService> dragService = static_cast<nsDragService*>(data);

  1805     return dragService->RunScheduledTask();

  1806 }

  1808 gboolean

  1809 nsDragService::RunScheduledTask()

  1810 {

  1811     if (mTargetWindow && mTargetWindow != mPendingWindow) {

  1812         PR_LOG(sDragLm, PR_LOG_DEBUG,

  1813                ("nsDragService: dispatch drag leave (%p)\n",

  1814                 mTargetWindow.get()));

  1815         mTargetWindow->

  1816             DispatchDragEvent(NS_DRAGDROP_EXIT, mTargetWindowPoint, 0);

  1818         if (!mSourceNode) {

  1819             // The drag that was initiated in a different app. End the drag

  1820             // session, since we're done with it for now (until the user drags

  1821             // back into this app).

  1822             EndDragSession(false);

  1823         }

  1824     }

  1826     // It is possible that the pending state has been updated during dispatch

  1827     // of the leave event.  That's fine.

  1829     // Now we collect the pending state because, from this point on, we want

  1830     // to use the same state for all events dispatched.  All state is updated

  1831     // so that when other tasks are scheduled during dispatch here, this

  1832     // task is considered to have already been run.

  1833     bool positionHasChanged =

  1834         mPendingWindow != mTargetWindow ||

  1835         mPendingWindowPoint != mTargetWindowPoint;

  1836     DragTask task = mScheduledTask;

  1837     mScheduledTask = eDragTaskNone;

  1838     mTargetWindow = mPendingWindow.forget();

  1839     mTargetWindowPoint = mPendingWindowPoint;

  1841     if (task == eDragTaskLeave || task == eDragTaskSourceEnd) {

  1842         if (task == eDragTaskSourceEnd) {

  1843             // Dispatch drag end events.

  1844             EndDragSession(true);

  1845         }

  1847         // Nothing more to do

  1848         // Returning false removes the task source from the event loop.

  1849         mTaskSource = 0;

  1850         return FALSE;

  1851     }

  1853     // This may be the start of a destination drag session.

  1854     StartDragSession();

  1856     // mTargetWidget may be nullptr if the window has been destroyed.

  1857     // (The leave event is not scheduled if a drop task is still scheduled.)

  1858     // We still reply appropriately to indicate that the drop will or didn't

  1859     // succeeed.

  1860     mTargetWidget = mTargetWindow->GetMozContainerWidget();

  1861     mTargetDragContext.steal(mPendingDragContext);

  1862     mTargetTime = mPendingTime;

  1864     // http://www.whatwg.org/specs/web-apps/current-work/multipage/dnd.html#drag-and-drop-processing-model

  1865     // (as at 27 December 2010) indicates that a "drop" event should only be

  1866     // fired (at the current target element) if the current drag operation is

  1867     // not none.  The current drag operation will only be set to a non-none

  1868     // value during a "dragover" event.

  1869     //

  1870     // If the user has ended the drag before any dragover events have been

  1871     // sent, then the spec recommends skipping the drop (because the current

  1872     // drag operation is none).  However, here we assume that, by releasing

  1873     // the mouse button, the user has indicated that they want to drop, so we

  1874     // proceed with the drop where possible.

  1875     //

  1876     // In order to make the events appear to content in the same way as if the

  1877     // spec is being followed we make sure to dispatch a "dragover" event with

  1878     // appropriate coordinates and check canDrop before the "drop" event.

  1879     //

  1880     // When the Xdnd protocol is used for source/destination communication (as

  1881     // should be the case with GTK source applications) a dragover event

  1882     // should have already been sent during the drag-motion signal, which

  1883     // would have already been received because XdndDrop messages do not

  1884     // contain a position.  However, we can't assume the same when the Motif

  1885     // protocol is used.

  1886     if (task == eDragTaskMotion || positionHasChanged) {

  1887         UpdateDragAction();

  1888         DispatchMotionEvents();

  1890         if (task == eDragTaskMotion) {

  1891             // Reply to tell the source whether we can drop and what

  1892             // action would be taken.

  1893             ReplyToDragMotion();

  1894         }

  1895     }

  1897     if (task == eDragTaskDrop) {

  1898         gboolean success = DispatchDropEvent();

  1900         // Perhaps we should set the del parameter to TRUE when the drag

  1901         // action is move, but we don't know whether the data was successfully

  1902         // transferred.

  1903         gtk_drag_finish(mTargetDragContext, success,

  1904                         /* del = */ FALSE, mTargetTime);

  1906         // This drag is over, so clear out our reference to the previous

  1907         // window.

  1908         mTargetWindow = nullptr;

  1909         // Make sure to end the drag session. If this drag started in a

  1910         // different app, we won't get a drag_end signal to end it from.

  1911         EndDragSession(true);

  1912     }

  1914     // We're done with the drag context.

  1915     mTargetWidget = nullptr;

  1916     mTargetDragContext = nullptr;

  1918     // If we got another drag signal while running the sheduled task, that

  1919     // must have happened while running a nested event loop.  Leave the task

  1920     // source on the event loop.

  1921     if (mScheduledTask != eDragTaskNone)

  1922         return TRUE;

  1924     // We have no task scheduled.

  1925     // Returning false removes the task source from the event loop.

  1926     mTaskSource = 0;

  1927     return FALSE;

  1928 }

  1930 // This will update the drag action based on the information in the

  1931 // drag context.  Gtk gets this from a combination of the key settings

  1932 // and what the source is offering.

  1934 void

  1935 nsDragService::UpdateDragAction()

  1936 {

  1937     // This doesn't look right.  dragSession.dragAction is used by

  1938     // nsContentUtils::SetDataTransferInEvent() to set the initial

  1939     // dataTransfer.dropEffect, so GdkDragContext::suggested_action would be

  1940     // more appropriate.  GdkDragContext::actions should be used to set

  1941     // dataTransfer.effectAllowed, which doesn't currently happen with

  1942     // external sources.

  1944     // default is to do nothing

  1945     int action = nsIDragService::DRAGDROP_ACTION_NONE;

  1946     GdkDragAction gdkAction = gdk_drag_context_get_actions(mTargetDragContext);

  1948     // set the default just in case nothing matches below

  1949     if (gdkAction & GDK_ACTION_DEFAULT)

  1950         action = nsIDragService::DRAGDROP_ACTION_MOVE;

  1952     // first check to see if move is set

  1953     if (gdkAction & GDK_ACTION_MOVE)

  1954         action = nsIDragService::DRAGDROP_ACTION_MOVE;

  1956     // then fall to the others

  1957     else if (gdkAction & GDK_ACTION_LINK)

  1958         action = nsIDragService::DRAGDROP_ACTION_LINK;

  1960     // copy is ctrl

  1961     else if (gdkAction & GDK_ACTION_COPY)

  1962         action = nsIDragService::DRAGDROP_ACTION_COPY;

  1964     // update the drag information

  1965     SetDragAction(action);

  1966 }

  1968 void

  1969 nsDragService::DispatchMotionEvents()

  1970 {

  1971     mCanDrop = false;

  1973     FireDragEventAtSource(NS_DRAGDROP_DRAG);

  1975     mTargetWindow->

  1976         DispatchDragEvent(NS_DRAGDROP_OVER, mTargetWindowPoint, mTargetTime);

  1977 }

  1979 // Returns true if the drop was successful

  1980 gboolean

  1981 nsDragService::DispatchDropEvent()

  1982 {

  1983     // We need to check IsDestroyed here because the nsRefPtr

  1984     // only protects this from being deleted, it does NOT protect

  1985     // against nsView::~nsView() calling Destroy() on it, bug 378273.

  1986     if (mTargetWindow->IsDestroyed())

  1987         return FALSE;

  1989     uint32_t msg = mCanDrop ? NS_DRAGDROP_DROP : NS_DRAGDROP_EXIT;

  1991     mTargetWindow->DispatchDragEvent(msg, mTargetWindowPoint, mTargetTime);

  1993     return mCanDrop;

  1994 }

The Tor Browser / file revision

widget/gtk/nsDragService.cpp@ac0c01689b40

widget/gtk/nsDragService.cpp