michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "mozilla/ArrayUtils.h"
michael@0: 
michael@0: #include "nsClipboardPrivacyHandler.h"
michael@0: #include "nsITransferable.h"
michael@0: #include "nsISupportsPrimitives.h"
michael@0: #include "nsIObserverService.h"
michael@0: #include "nsIClipboard.h"
michael@0: #include "nsComponentManagerUtils.h"
michael@0: #include "nsServiceManagerUtils.h"
michael@0: #include "nsLiteralString.h"
michael@0: #include "nsNetCID.h"
michael@0: #include "nsXPCOM.h"
michael@0: #include "mozilla/Services.h"
michael@0: 
michael@0: #if defined(XP_WIN)
michael@0: #include <ole2.h>
michael@0: #endif
michael@0: 
michael@0: using namespace mozilla;
michael@0: 
michael@0: #define NS_MOZ_DATA_FROM_PRIVATEBROWSING "application/x-moz-private-browsing"
michael@0: 
michael@0: NS_IMPL_ISUPPORTS(nsClipboardPrivacyHandler, nsIObserver, nsISupportsWeakReference)
michael@0: 
michael@0: nsresult
michael@0: nsClipboardPrivacyHandler::Init()
michael@0: {
michael@0:   nsCOMPtr<nsIObserverService> observerService =
michael@0:     mozilla::services::GetObserverService();
michael@0:   if (!observerService)
michael@0:     return NS_ERROR_FAILURE;
michael@0:   return observerService->AddObserver(this, "last-pb-context-exited", true);
michael@0: }
michael@0: 
michael@0: /**
michael@0:   * Prepare the transferable object to be inserted into the clipboard
michael@0:   *
michael@0:   */
michael@0: nsresult
michael@0: nsClipboardPrivacyHandler::PrepareDataForClipboard(nsITransferable * aTransferable)
michael@0: {
michael@0:   NS_ASSERTION(aTransferable, "clipboard given a null transferable");
michael@0: 
michael@0:   bool isPrivateData = false;
michael@0:   aTransferable->GetIsPrivateData(&isPrivateData);
michael@0: 
michael@0:   nsresult rv = NS_OK;
michael@0:   if (isPrivateData) {
michael@0:     nsCOMPtr<nsISupportsPRBool> data = do_CreateInstance(NS_SUPPORTS_PRBOOL_CONTRACTID);
michael@0:     if (data) {
michael@0:       rv = data->SetData(true);
michael@0:       NS_ENSURE_SUCCESS(rv, rv);
michael@0: 
michael@0:       // Ignore the error code of AddDataFlavor, since we might have added
michael@0:       // this flavor before.  If this call really fails, so will the next
michael@0:       // one (SetTransferData).
michael@0:       aTransferable->AddDataFlavor(NS_MOZ_DATA_FROM_PRIVATEBROWSING);
michael@0: 
michael@0:       rv = aTransferable->SetTransferData(NS_MOZ_DATA_FROM_PRIVATEBROWSING, data, sizeof(bool));
michael@0:       NS_ENSURE_SUCCESS(rv, rv);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   return rv;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsClipboardPrivacyHandler::Observe(nsISupports *aSubject, char const *aTopic, char16_t const *aData)
michael@0: {
michael@0:   nsresult rv;
michael@0:   nsCOMPtr<nsIClipboard> clipboard =
michael@0:     do_GetService("@mozilla.org/widget/clipboard;1", &rv);
michael@0:   NS_ENSURE_SUCCESS(rv, rv);
michael@0: 
michael@0:   const char * flavors[] = { NS_MOZ_DATA_FROM_PRIVATEBROWSING };
michael@0:   bool haveFlavors;
michael@0:   rv = clipboard->HasDataMatchingFlavors(flavors,
michael@0:                                          ArrayLength(flavors),
michael@0:                                          nsIClipboard::kGlobalClipboard,
michael@0:                                          &haveFlavors);
michael@0:   if (NS_SUCCEEDED(rv) && haveFlavors) {
michael@0: #if defined(XP_WIN)
michael@0:     // Workaround for bug 518412.  On Windows 7 x64, there is a bug
michael@0:     // in handling clipboard data without any formats between
michael@0:     // 32-bit/64-bit boundaries, which could lead Explorer to crash.
michael@0:     // We work around the problem by clearing the clipboard using
michael@0:     // the usual Win32 API.
michael@0:     NS_ENSURE_TRUE(SUCCEEDED(::OleSetClipboard(nullptr)), NS_ERROR_FAILURE);
michael@0: #else
michael@0:     // Empty the native clipboard by copying an empty transferable
michael@0:     nsCOMPtr<nsITransferable> nullData =
michael@0:       do_CreateInstance("@mozilla.org/widget/transferable;1", &rv);
michael@0:     NS_ENSURE_SUCCESS(rv, rv);
michael@0:     nullData->Init(nullptr);
michael@0:     rv = clipboard->SetData(nullData, nullptr,
michael@0:                             nsIClipboard::kGlobalClipboard);
michael@0:     NS_ENSURE_SUCCESS(rv, rv);
michael@0: #endif
michael@0:   }
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: NS_NewClipboardPrivacyHandler(nsClipboardPrivacyHandler ** aHandler)
michael@0: {
michael@0:   NS_PRECONDITION(aHandler != nullptr, "null ptr");
michael@0:   if (!aHandler)
michael@0:     return NS_ERROR_NULL_POINTER;
michael@0: 
michael@0:   *aHandler = new nsClipboardPrivacyHandler();
michael@0: 
michael@0:   NS_ADDREF(*aHandler);
michael@0:   nsresult rv = (*aHandler)->Init();
michael@0:   if (NS_FAILED(rv))
michael@0:     NS_RELEASE(*aHandler);
michael@0: 
michael@0:   return rv;
michael@0: }