The Tor Browser: widget/xpwidgets/nsClipboardPrivacyHandler.cpp@b8a032363ba2

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

     1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

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

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

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

     6 #include "mozilla/ArrayUtils.h"

     8 #include "nsClipboardPrivacyHandler.h"

     9 #include "nsITransferable.h"

    10 #include "nsISupportsPrimitives.h"

    11 #include "nsIObserverService.h"

    12 #include "nsIClipboard.h"

    13 #include "nsComponentManagerUtils.h"

    14 #include "nsServiceManagerUtils.h"

    15 #include "nsLiteralString.h"

    16 #include "nsNetCID.h"

    17 #include "nsXPCOM.h"

    18 #include "mozilla/Services.h"

    20 #if defined(XP_WIN)

    21 #include <ole2.h>

    22 #endif

    24 using namespace mozilla;

    26 #define NS_MOZ_DATA_FROM_PRIVATEBROWSING "application/x-moz-private-browsing"

    28 NS_IMPL_ISUPPORTS(nsClipboardPrivacyHandler, nsIObserver, nsISupportsWeakReference)

    30 nsresult

    31 nsClipboardPrivacyHandler::Init()

    32 {

    33   nsCOMPtr<nsIObserverService> observerService =

    34     mozilla::services::GetObserverService();

    35   if (!observerService)

    36     return NS_ERROR_FAILURE;

    37   return observerService->AddObserver(this, "last-pb-context-exited", true);

    38 }

    40 /**

    41   * Prepare the transferable object to be inserted into the clipboard

    42   *

    43   */

    44 nsresult

    45 nsClipboardPrivacyHandler::PrepareDataForClipboard(nsITransferable * aTransferable)

    46 {

    47   NS_ASSERTION(aTransferable, "clipboard given a null transferable");

    49   bool isPrivateData = false;

    50   aTransferable->GetIsPrivateData(&isPrivateData);

    52   nsresult rv = NS_OK;

    53   if (isPrivateData) {

    54     nsCOMPtr<nsISupportsPRBool> data = do_CreateInstance(NS_SUPPORTS_PRBOOL_CONTRACTID);

    55     if (data) {

    56       rv = data->SetData(true);

    57       NS_ENSURE_SUCCESS(rv, rv);

    59       // Ignore the error code of AddDataFlavor, since we might have added

    60       // this flavor before.  If this call really fails, so will the next

    61       // one (SetTransferData).

    62       aTransferable->AddDataFlavor(NS_MOZ_DATA_FROM_PRIVATEBROWSING);

    64       rv = aTransferable->SetTransferData(NS_MOZ_DATA_FROM_PRIVATEBROWSING, data, sizeof(bool));

    65       NS_ENSURE_SUCCESS(rv, rv);

    66     }

    67   }

    69   return rv;

    70 }

    72 NS_IMETHODIMP

    73 nsClipboardPrivacyHandler::Observe(nsISupports *aSubject, char const *aTopic, char16_t const *aData)

    74 {

    75   nsresult rv;

    76   nsCOMPtr<nsIClipboard> clipboard =

    77     do_GetService("@mozilla.org/widget/clipboard;1", &rv);

    78   NS_ENSURE_SUCCESS(rv, rv);

    80   const char * flavors[] = { NS_MOZ_DATA_FROM_PRIVATEBROWSING };

    81   bool haveFlavors;

    82   rv = clipboard->HasDataMatchingFlavors(flavors,

    83                                          ArrayLength(flavors),

    84                                          nsIClipboard::kGlobalClipboard,

    85                                          &haveFlavors);

    86   if (NS_SUCCEEDED(rv) && haveFlavors) {

    87 #if defined(XP_WIN)

    88     // Workaround for bug 518412.  On Windows 7 x64, there is a bug

    89     // in handling clipboard data without any formats between

    90     // 32-bit/64-bit boundaries, which could lead Explorer to crash.

    91     // We work around the problem by clearing the clipboard using

    92     // the usual Win32 API.

    93     NS_ENSURE_TRUE(SUCCEEDED(::OleSetClipboard(nullptr)), NS_ERROR_FAILURE);

    94 #else

    95     // Empty the native clipboard by copying an empty transferable

    96     nsCOMPtr<nsITransferable> nullData =

    97       do_CreateInstance("@mozilla.org/widget/transferable;1", &rv);

    98     NS_ENSURE_SUCCESS(rv, rv);

    99     nullData->Init(nullptr);

   100     rv = clipboard->SetData(nullData, nullptr,

   101                             nsIClipboard::kGlobalClipboard);

   102     NS_ENSURE_SUCCESS(rv, rv);

   103 #endif

   104   }

   106   return NS_OK;

   107 }

   109 nsresult

   110 NS_NewClipboardPrivacyHandler(nsClipboardPrivacyHandler ** aHandler)

   111 {

   112   NS_PRECONDITION(aHandler != nullptr, "null ptr");

   113   if (!aHandler)

   114     return NS_ERROR_NULL_POINTER;

   116   *aHandler = new nsClipboardPrivacyHandler();

   118   NS_ADDREF(*aHandler);

   119   nsresult rv = (*aHandler)->Init();

   120   if (NS_FAILED(rv))

   121     NS_RELEASE(*aHandler);

   123   return rv;

   124 }

The Tor Browser / file revision