The Tor Browser: widget/windows/nsDragService.cpp@ac0c01689b40 (annotated)

widget/windows/nsDragService.cpp@ac0c01689b40 (annotated)

widget/windows/nsDragService.cpp

Thu, 15 Jan 2015 15:59:08 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 15:59:08 +0100
branch: TOR_BUG_9701
changeset 10: ac0c01689b40
permissions: -rw-r--r--

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.

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include <ole2.h>
 #include <oleidl.h>
 #include <shlobj.h>
 #include <shlwapi.h>
 // shellapi.h is needed to build with WIN32_LEAN_AND_MEAN
 #include <shellapi.h>
 #include "nsDragService.h"
 #include "nsITransferable.h"
 #include "nsDataObj.h"
 #include "nsWidgetsCID.h"
 #include "nsNativeDragTarget.h"
 #include "nsNativeDragSource.h"
 #include "nsClipboard.h"
 #include "nsISupportsArray.h"
 #include "nsIDocument.h"
 #include "nsDataObjCollection.h"
 #include "nsAutoPtr.h"
 #include "nsString.h"
 #include "nsEscape.h"
 #include "nsISupportsPrimitives.h"
 #include "nsNetUtil.h"
 #include "nsIURL.h"
 #include "nsCWebBrowserPersist.h"
 #include "nsToolkit.h"
 #include "nsCRT.h"
 #include "nsDirectoryServiceDefs.h"
 #include "nsUnicharUtils.h"
 #include "gfxContext.h"
 #include "nsRect.h"
 #include "nsMathUtils.h"
 #include "gfxWindowsPlatform.h"
 #include "mozilla/gfx/2D.h"
 #include "mozilla/gfx/DataSurfaceHelpers.h"
 #include "mozilla/gfx/Tools.h"
 using namespace mozilla;
 using namespace mozilla::gfx;
 //-------------------------------------------------------------------------
 //
 // DragService constructor
 //
 //-------------------------------------------------------------------------
 nsDragService::nsDragService()
   : mDataObject(nullptr), mSentLocalDropEvent(false)
 {
 }
 //-------------------------------------------------------------------------
 //
 // DragService destructor
 //
 //-------------------------------------------------------------------------
 nsDragService::~nsDragService()
 {
   NS_IF_RELEASE(mDataObject);
 }
 bool
 nsDragService::CreateDragImage(nsIDOMNode *aDOMNode,
                                nsIScriptableRegion *aRegion,
                                SHDRAGIMAGE *psdi)
 {
   if (!psdi)
     return false;
   memset(psdi, 0, sizeof(SHDRAGIMAGE));
   if (!aDOMNode)
     return false;
   // Prepare the drag image
   nsIntRect dragRect;
   RefPtr<SourceSurface> surface;
   nsPresContext* pc;
   DrawDrag(aDOMNode, aRegion,
            mScreenX, mScreenY,
            &dragRect, &surface, &pc);
   if (!surface)
     return false;
   uint32_t bmWidth = dragRect.width, bmHeight = dragRect.height;
   if (bmWidth == 0 || bmHeight == 0)
     return false;
   psdi->crColorKey = CLR_NONE;
   RefPtr<DataSourceSurface> dataSurface =
     Factory::CreateDataSourceSurface(IntSize(bmWidth, bmHeight),
                                      SurfaceFormat::B8G8R8A8);
   NS_ENSURE_TRUE(dataSurface, false);
   DataSourceSurface::MappedSurface map;
   if (!dataSurface->Map(DataSourceSurface::MapType::READ_WRITE, &map)) {
     return false;
   }
   RefPtr<DrawTarget> dt =
     Factory::CreateDrawTargetForData(BackendType::CAIRO,
                                      map.mData,
                                      dataSurface->GetSize(),
                                      map.mStride,
                                      dataSurface->GetFormat());
   if (!dt) {
     dataSurface->Unmap();
     return false;
   }
   dt->DrawSurface(surface,
                   Rect(0, 0, dataSurface->GetSize().width, dataSurface->GetSize().height),
                   Rect(0, 0, surface->GetSize().width, surface->GetSize().height),
                   DrawSurfaceOptions(),
                   DrawOptions(1.0f, CompositionOp::OP_SOURCE));
   dt->Flush();
   BITMAPV5HEADER bmih;
   memset((void*)&bmih, 0, sizeof(BITMAPV5HEADER));
   bmih.bV5Size        = sizeof(BITMAPV5HEADER);
   bmih.bV5Width       = bmWidth;
   bmih.bV5Height      = -(int32_t)bmHeight; // flip vertical
   bmih.bV5Planes      = 1;
   bmih.bV5BitCount    = 32;
   bmih.bV5Compression = BI_BITFIELDS;
   bmih.bV5RedMask     = 0x00FF0000;
   bmih.bV5GreenMask   = 0x0000FF00;
   bmih.bV5BlueMask    = 0x000000FF;
   bmih.bV5AlphaMask   = 0xFF000000;
   HDC hdcSrc = CreateCompatibleDC(nullptr);
   void *lpBits = nullptr;
   if (hdcSrc) {
     psdi->hbmpDragImage =
     ::CreateDIBSection(hdcSrc, (BITMAPINFO*)&bmih, DIB_RGB_COLORS,
                        (void**)&lpBits, nullptr, 0);
     if (psdi->hbmpDragImage && lpBits) {
       CopySurfaceDataToPackedArray(map.mData, static_cast<uint8_t*>(lpBits),
                                    dataSurface->GetSize(), map.mStride,
                                    BytesPerPixel(dataSurface->GetFormat()));
     }
     psdi->sizeDragImage.cx = bmWidth;
     psdi->sizeDragImage.cy = bmHeight;
     // Mouse position in center
     if (mScreenX == -1 || mScreenY == -1) {
       psdi->ptOffset.x = (uint32_t)((float)bmWidth/2.0f);
       psdi->ptOffset.y = (uint32_t)((float)bmHeight/2.0f);
     } else {
       int32_t sx = mScreenX, sy = mScreenY;
       ConvertToUnscaledDevPixels(pc, &sx, &sy);
       psdi->ptOffset.x = sx - dragRect.x;
       psdi->ptOffset.y = sy - dragRect.y;
     }
     DeleteDC(hdcSrc);
   }
   dataSurface->Unmap();
   return psdi->hbmpDragImage != nullptr;
 }
 //-------------------------------------------------------------------------
 NS_IMETHODIMP
 nsDragService::InvokeDragSession(nsIDOMNode *aDOMNode,
                                  nsISupportsArray *anArrayTransferables,
                                  nsIScriptableRegion *aRegion,
                                  uint32_t aActionType)
 {
   nsresult rv = nsBaseDragService::InvokeDragSession(aDOMNode,
                                                      anArrayTransferables,
                                                      aRegion,
                                                      aActionType);
   NS_ENSURE_SUCCESS(rv, rv);
   // Try and get source URI of the items that are being dragged
   nsIURI *uri = nullptr;
   nsCOMPtr<nsIDocument> doc(do_QueryInterface(mSourceDocument));
   if (doc) {
     uri = doc->GetDocumentURI();
   }
   uint32_t numItemsToDrag = 0;
   rv = anArrayTransferables->Count(&numItemsToDrag);
   if (!numItemsToDrag)
     return NS_ERROR_FAILURE;
   // The clipboard class contains some static utility methods that we
   // can use to create an IDataObject from the transferable
   // if we're dragging more than one item, we need to create a
   // "collection" object to fake out the OS. This collection contains
   // one |IDataObject| for each transferable. If there is just the one
   // (most cases), only pass around the native |IDataObject|.
   nsRefPtr<IDataObject> itemToDrag;
   if (numItemsToDrag > 1) {
     nsDataObjCollection * dataObjCollection = new nsDataObjCollection();
     if (!dataObjCollection)
       return NS_ERROR_OUT_OF_MEMORY;
     itemToDrag = dataObjCollection;
     for (uint32_t i=0; i<numItemsToDrag; ++i) {
       nsCOMPtr<nsISupports> supports;
       anArrayTransferables->GetElementAt(i, getter_AddRefs(supports));
       nsCOMPtr<nsITransferable> trans(do_QueryInterface(supports));
       if (trans) {
         nsRefPtr<IDataObject> dataObj;
         rv = nsClipboard::CreateNativeDataObject(trans,
                                                  getter_AddRefs(dataObj), uri);
         NS_ENSURE_SUCCESS(rv, rv);
         // Add the flavors to the collection object too
         rv = nsClipboard::SetupNativeDataObject(trans, dataObjCollection);
         NS_ENSURE_SUCCESS(rv, rv);
         dataObjCollection->AddDataObject(dataObj);
       }
     }
   } // if dragging multiple items
   else {
     nsCOMPtr<nsISupports> supports;
     anArrayTransferables->GetElementAt(0, getter_AddRefs(supports));
     nsCOMPtr<nsITransferable> trans(do_QueryInterface(supports));
     if (trans) {
       rv = nsClipboard::CreateNativeDataObject(trans,
                                                getter_AddRefs(itemToDrag),
                                                uri);
       NS_ENSURE_SUCCESS(rv, rv);
     }
   } // else dragging a single object
   // Create a drag image if support is available
   IDragSourceHelper *pdsh;
   if (SUCCEEDED(CoCreateInstance(CLSID_DragDropHelper, nullptr,
                                  CLSCTX_INPROC_SERVER,
                                  IID_IDragSourceHelper, (void**)&pdsh))) {
     SHDRAGIMAGE sdi;
     if (CreateDragImage(aDOMNode, aRegion, &sdi)) {
       if (FAILED(pdsh->InitializeFromBitmap(&sdi, itemToDrag)))
         DeleteObject(sdi.hbmpDragImage);
     }
     pdsh->Release();
   }
   // Kick off the native drag session
   return StartInvokingDragSession(itemToDrag, aActionType);
 }
 //-------------------------------------------------------------------------
 NS_IMETHODIMP
 nsDragService::StartInvokingDragSession(IDataObject * aDataObj,
                                         uint32_t aActionType)
 {
   // To do the drag we need to create an object that
   // implements the IDataObject interface (for OLE)
   nsRefPtr<nsNativeDragSource> nativeDragSrc =
     new nsNativeDragSource(mDataTransfer);
   // Now figure out what the native drag effect should be
   DWORD winDropRes;
   DWORD effects = DROPEFFECT_SCROLL;
   if (aActionType & DRAGDROP_ACTION_COPY) {
     effects |= DROPEFFECT_COPY;
   }
   if (aActionType & DRAGDROP_ACTION_MOVE) {
     effects |= DROPEFFECT_MOVE;
   }
   if (aActionType & DRAGDROP_ACTION_LINK) {
     effects |= DROPEFFECT_LINK;
   }
   // XXX not sure why we bother to cache this, it can change during
   // the drag
   mDragAction = aActionType;
   mSentLocalDropEvent = false;
   // Start dragging
   StartDragSession();
   OpenDragPopup();
   nsRefPtr<IAsyncOperation> pAsyncOp;
   // Offer to do an async drag
   if (SUCCEEDED(aDataObj->QueryInterface(IID_IAsyncOperation,
                                          getter_AddRefs(pAsyncOp)))) {
     pAsyncOp->SetAsyncMode(VARIANT_TRUE);
   } else {
     NS_NOTREACHED("When did our data object stop being async");
   }
   // Call the native D&D method
   HRESULT res = ::DoDragDrop(aDataObj, nativeDragSrc, effects, &winDropRes);
   // In  cases where the drop operation completed outside the application, update
   // the source node's nsIDOMDataTransfer dropEffect value so it is up to date.
   if (!mSentLocalDropEvent) {
     uint32_t dropResult;
     // Order is important, since multiple flags can be returned.
     if (winDropRes & DROPEFFECT_COPY)
         dropResult = DRAGDROP_ACTION_COPY;
     else if (winDropRes & DROPEFFECT_LINK)
         dropResult = DRAGDROP_ACTION_LINK;
     else if (winDropRes & DROPEFFECT_MOVE)
         dropResult = DRAGDROP_ACTION_MOVE;
     else
         dropResult = DRAGDROP_ACTION_NONE;
     if (mDataTransfer) {
       if (res == DRAGDROP_S_DROP) // Success
         mDataTransfer->SetDropEffectInt(dropResult);
       else
         mDataTransfer->SetDropEffectInt(DRAGDROP_ACTION_NONE);
     }
   }
   mUserCancelled = nativeDragSrc->UserCancelled();
   // We're done dragging, get the cursor position and end the drag
   // Use GetMessagePos to get the position of the mouse at the last message
   // seen by the event loop. (Bug 489729)
   // Note that we must convert this from device pixels back to Windows logical
   // pixels (bug 818927).
   DWORD pos = ::GetMessagePos();
   FLOAT dpiScale = gfxWindowsPlatform::GetPlatform()->GetDPIScale();
   nsIntPoint logPos(NSToIntRound(GET_X_LPARAM(pos) / dpiScale),
                     NSToIntRound(GET_Y_LPARAM(pos) / dpiScale));
   SetDragEndPoint(logPos);
   EndDragSession(true);
   mDoingDrag = false;
   return DRAGDROP_S_DROP == res ? NS_OK : NS_ERROR_FAILURE;
 }
 //-------------------------------------------------------------------------
 // Make Sure we have the right kind of object
 nsDataObjCollection*
 nsDragService::GetDataObjCollection(IDataObject* aDataObj)
 {
   nsDataObjCollection * dataObjCol = nullptr;
   if (aDataObj) {
     nsIDataObjCollection* dataObj;
     if (aDataObj->QueryInterface(IID_IDataObjCollection,
                                  (void**)&dataObj) == S_OK) {
       dataObjCol = static_cast<nsDataObjCollection*>(aDataObj);
       dataObj->Release();
     }
   }
   return dataObjCol;
 }
 //-------------------------------------------------------------------------
 NS_IMETHODIMP
 nsDragService::GetNumDropItems(uint32_t * aNumItems)
 {
   if (!mDataObject) {
     *aNumItems = 0;
     return NS_OK;
   }
   if (IsCollectionObject(mDataObject)) {
     nsDataObjCollection * dataObjCol = GetDataObjCollection(mDataObject);
     if (dataObjCol) {
       *aNumItems = dataObjCol->GetNumDataObjects();
     }
     else {
       // If the count cannot be determined just return 0.
       // This can happen if we have collection data of type
       // MULTI_MIME ("Mozilla/IDataObjectCollectionFormat") on the clipboard
       // from another process but we can't obtain an IID_IDataObjCollection
       // from this process.
       *aNumItems = 0;
     }
   }
   else {
     // Next check if we have a file drop. Return the number of files in
     // the file drop as the number of items we have, pretending like we
     // actually have > 1 drag item.
     FORMATETC fe2;
     SET_FORMATETC(fe2, CF_HDROP, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL);
     if (mDataObject->QueryGetData(&fe2) == S_OK) {
       STGMEDIUM stm;
       if (mDataObject->GetData(&fe2, &stm) == S_OK) {
         HDROP hdrop = (HDROP)GlobalLock(stm.hGlobal);
         *aNumItems = ::DragQueryFileW(hdrop, 0xFFFFFFFF, nullptr, 0);
         ::GlobalUnlock(stm.hGlobal);
         ::ReleaseStgMedium(&stm);
         // Data may be provided later, so assume we have 1 item
         if (*aNumItems == 0)
           *aNumItems = 1;
       }
       else
         *aNumItems = 1;
     }
     else
       *aNumItems = 1;
   }
   return NS_OK;
 }
 //-------------------------------------------------------------------------
 NS_IMETHODIMP
 nsDragService::GetData(nsITransferable * aTransferable, uint32_t anItem)
 {
   // This typcially happens on a drop, the target would be asking
   // for it's transferable to be filled in
   // Use a static clipboard utility method for this
   if (!mDataObject)
     return NS_ERROR_FAILURE;
   nsresult dataFound = NS_ERROR_FAILURE;
   if (IsCollectionObject(mDataObject)) {
     // multiple items, use |anItem| as an index into our collection
     nsDataObjCollection * dataObjCol = GetDataObjCollection(mDataObject);
     uint32_t cnt = dataObjCol->GetNumDataObjects();
     if (anItem >= 0 && anItem < cnt) {
       IDataObject * dataObj = dataObjCol->GetDataObjectAt(anItem);
       dataFound = nsClipboard::GetDataFromDataObject(dataObj, 0, nullptr,
                                                      aTransferable);
     }
     else
       NS_WARNING("Index out of range!");
   }
   else {
     // If they are asking for item "0", we can just get it...
     if (anItem == 0) {
        dataFound = nsClipboard::GetDataFromDataObject(mDataObject, anItem,
                                                       nullptr, aTransferable);
     } else {
       // It better be a file drop, or else non-zero indexes are invalid!
       FORMATETC fe2;
       SET_FORMATETC(fe2, CF_HDROP, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL);
       if (mDataObject->QueryGetData(&fe2) == S_OK)
         dataFound = nsClipboard::GetDataFromDataObject(mDataObject, anItem,
                                                        nullptr, aTransferable);
       else
         NS_WARNING("Reqesting non-zero index, but clipboard data is not a collection!");
     }
   }
   return dataFound;
 }
 //---------------------------------------------------------
 NS_IMETHODIMP
 nsDragService::SetIDataObject(IDataObject * aDataObj)
 {
   // When the native drag starts the DragService gets
   // the IDataObject that is being dragged
   NS_IF_RELEASE(mDataObject);
   mDataObject = aDataObj;
   NS_IF_ADDREF(mDataObject);
   return NS_OK;
 }
 //---------------------------------------------------------
 void
 nsDragService::SetDroppedLocal()
 {
   // Sent from the native drag handler, letting us know
   // a drop occurred within the application vs. outside of it.
   mSentLocalDropEvent = true;
   return;
 }
 //-------------------------------------------------------------------------
 NS_IMETHODIMP
 nsDragService::IsDataFlavorSupported(const char *aDataFlavor, bool *_retval)
 {
   if (!aDataFlavor || !mDataObject || !_retval)
     return NS_ERROR_FAILURE;
 #ifdef DEBUG
   if (strcmp(aDataFlavor, kTextMime) == 0)
     NS_WARNING("DO NOT USE THE text/plain DATA FLAVOR ANY MORE. USE text/unicode INSTEAD");
 #endif
   *_retval = false;
   FORMATETC fe;
   UINT format = 0;
   if (IsCollectionObject(mDataObject)) {
     // We know we have one of our special collection objects.
     format = nsClipboard::GetFormat(aDataFlavor);
     SET_FORMATETC(fe, format, 0, DVASPECT_CONTENT, -1,
                   TYMED_HGLOBAL | TYMED_FILE | TYMED_GDI);
     // See if any one of the IDataObjects in the collection supports
     // this data type
     nsDataObjCollection* dataObjCol = GetDataObjCollection(mDataObject);
     if (dataObjCol) {
       uint32_t cnt = dataObjCol->GetNumDataObjects();
       for (uint32_t i=0;i<cnt;++i) {
         IDataObject * dataObj = dataObjCol->GetDataObjectAt(i);
         if (S_OK == dataObj->QueryGetData(&fe))
           *_retval = true;             // found it!
       }
     }
   } // if special collection object
   else {
     // Ok, so we have a single object. Check to see if has the correct
     // data type. Since this can come from an outside app, we also
     // need to see if we need to perform text->unicode conversion if
     // the client asked for unicode and it wasn't available.
     format = nsClipboard::GetFormat(aDataFlavor);
     SET_FORMATETC(fe, format, 0, DVASPECT_CONTENT, -1,
                   TYMED_HGLOBAL | TYMED_FILE | TYMED_GDI);
     if (mDataObject->QueryGetData(&fe) == S_OK)
       *_retval = true;                 // found it!
     else {
       // We haven't found the exact flavor the client asked for, but
       // maybe we can still find it from something else that's on the
       // clipboard
       if (strcmp(aDataFlavor, kUnicodeMime) == 0) {
         // client asked for unicode and it wasn't present, check if we
         // have CF_TEXT.  We'll handle the actual data substitution in
         // the data object.
         format = nsClipboard::GetFormat(kTextMime);
         SET_FORMATETC(fe, format, 0, DVASPECT_CONTENT, -1,
                       TYMED_HGLOBAL | TYMED_FILE | TYMED_GDI);
         if (mDataObject->QueryGetData(&fe) == S_OK)
           *_retval = true;                 // found it!
       }
       else if (strcmp(aDataFlavor, kURLMime) == 0) {
         // client asked for a url and it wasn't present, but if we
         // have a file, then we have a URL to give them (the path, or
         // the internal URL if an InternetShortcut).
         format = nsClipboard::GetFormat(kFileMime);
         SET_FORMATETC(fe, format, 0, DVASPECT_CONTENT, -1,
                       TYMED_HGLOBAL | TYMED_FILE | TYMED_GDI);
         if (mDataObject->QueryGetData(&fe) == S_OK)
           *_retval = true;                 // found it!
       }
     } // else try again
   }
   return NS_OK;
 }
 //
 // IsCollectionObject
 //
 // Determine if this is a single |IDataObject| or one of our private
 // collection objects. We know the difference because our collection
 // object will respond to supporting the private |MULTI_MIME| format.
 //
 bool
 nsDragService::IsCollectionObject(IDataObject* inDataObj)
 {
   bool isCollection = false;
   // setup the format object to ask for the MULTI_MIME format. We only
   // need to do this once
   static UINT sFormat = 0;
   static FORMATETC sFE;
   if (!sFormat) {
     sFormat = nsClipboard::GetFormat(MULTI_MIME);
     SET_FORMATETC(sFE, sFormat, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL);
   }
   // ask the object if it supports it. If yes, we have a collection
   // object
   if (inDataObj->QueryGetData(&sFE) == S_OK)
     isCollection = true;
   return isCollection;
 } // IsCollectionObject
 //
 // EndDragSession
 //
 // Override the default to make sure that we release the data object
 // when the drag ends. It seems that OLE doesn't like to let apps quit
 // w/out crashing when we're still holding onto their data
 //
 NS_IMETHODIMP
 nsDragService::EndDragSession(bool aDoneDrag)
 {
   // Bug 100180: If we've got mouse events captured, make sure we release it -
   // that way, if we happen to call EndDragSession before diving into a nested
   // event loop, we can still respond to mouse events.
   if (::GetCapture()) {
     ::ReleaseCapture();
   }
   nsBaseDragService::EndDragSession(aDoneDrag);
   NS_IF_RELEASE(mDataObject);
   return NS_OK;
 }

The Tor Browser / annotate

widget/windows/nsDragService.cpp@ac0c01689b40 (annotated)

widget/windows/nsDragService.cpp