widget/nsDragServiceProxy.cpp

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   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/. */
   6
   7 #include "nsDragServiceProxy.h"
   8 #include "nsIDocument.h"
   9 #include "nsISupportsPrimitives.h"
  10 #include "mozilla/dom/TabChild.h"
  11 #include "mozilla/gfx/2D.h"
  12 #include "mozilla/UniquePtr.h"
  13 #include "mozilla/Unused.h"
  14 #include "nsContentUtils.h"
  15
  16 using mozilla::ipc::Shmem;
  17 using mozilla::dom::TabChild;
  18 using mozilla::dom::OptionalShmem;
  19 using mozilla::LayoutDeviceIntRect;
  20 using mozilla::Maybe;
  21
  22 nsDragServiceProxy::nsDragServiceProxy()
  23 {
  24 }
  25
  26 nsDragServiceProxy::~nsDragServiceProxy()
  27 {
  28 }
  29
  30 static void
  31 GetPrincipalURIFromNode(nsCOMPtr<nsINode>& sourceNode,
  32                         nsCString& aPrincipalURISpec)
  33 {
  34   if (!sourceNode) {
  35     return;
  36   }
  37
  38   nsCOMPtr<nsIPrincipal> principal = sourceNode->NodePrincipal();
  39   nsCOMPtr<nsIURI> principalURI;
  40   nsresult rv = principal->GetURI(getter_AddRefs(principalURI));
  41   if (NS_FAILED(rv) || !principalURI) {
  42     return;
  43   }
  44
  45   principalURI->GetSpec(aPrincipalURISpec);
  46 }
  47
  48 nsresult
  49 nsDragServiceProxy::InvokeDragSessionImpl(nsIArray* aArrayTransferables,
  50                                           nsIScriptableRegion* aRegion,
  51                                           uint32_t aActionType)
  52 {
  53   NS_ENSURE_STATE(mSourceDocument->GetDocShell());
  54   TabChild* child = TabChild::GetFrom(mSourceDocument->GetDocShell());
  55   NS_ENSURE_STATE(child);
  56   nsTArray<mozilla::dom::IPCDataTransfer> dataTransfers;
  57   nsContentUtils::TransferablesToIPCTransferables(aArrayTransferables,
  58                                                   dataTransfers,
  59                                                   false,
  60                                                   child->Manager(),
  61                                                   nullptr);
  62
  63   nsCString principalURISpec;
  64   GetPrincipalURIFromNode(mSourceNode, principalURISpec);
  65
  66   LayoutDeviceIntRect dragRect;
  67   if (mHasImage || mSelection) {
  68     nsPresContext* pc;
  69     RefPtr<mozilla::gfx::SourceSurface> surface;
  70     DrawDrag(mSourceNode, aRegion, mScreenPosition, &dragRect, &surface, &pc);
  71
  72     if (surface) {
  73       RefPtr<mozilla::gfx::DataSourceSurface> dataSurface =
  74         surface->GetDataSurface();
  75       if (dataSurface) {
  76         size_t length;
  77         int32_t stride;
  78         Maybe<Shmem> maybeShm = nsContentUtils::GetSurfaceData(dataSurface,
  79                                                                &length,
  80                                                                &stride,
  81                                                                child);
  82         if (maybeShm.isNothing()) {
  83           return NS_ERROR_FAILURE;
  84         }
  85
  86         auto surfaceData = maybeShm.value();
  87
  88         // Save the surface data to shared memory.
  89         if (!surfaceData.IsReadable() || !surfaceData.get<char>()) {
  90           NS_WARNING("Failed to create shared memory for drag session.");
  91           return NS_ERROR_FAILURE;
  92         }
  93
  94         mozilla::Unused <<
  95           child->SendInvokeDragSession(dataTransfers, aActionType, surfaceData,
  96                                        stride, dataSurface->GetFormat(),
  97                                        dragRect, principalURISpec);
  98         StartDragSession();
  99         return NS_OK;
 100       }
 101     }
 102   }
 103
 104   mozilla::Unused << child->SendInvokeDragSession(dataTransfers, aActionType,
 105                                                   mozilla::void_t(), 0, static_cast<gfx::SurfaceFormat>(0), dragRect,
 106                                                   principalURISpec);
 107   StartDragSession();
 108   return NS_OK;
 109 }