The Tor Browser: dom/file/FileHandle.cpp@ac0c01689b40 (annotated)

dom/file/FileHandle.cpp@ac0c01689b40 (annotated)

dom/file/FileHandle.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: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* vim: set ts=2 et sw=2 tw=80: */
 /* 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 "FileHandle.h"
 #include "nsContentUtils.h"
 #include "nsDOMClassInfoID.h"
 #include "nsNetUtil.h"
 #include "nsIDOMFile.h"
 #include "nsIFileStorage.h"
 #include "File.h"
 #include "FileRequest.h"
 #include "FileService.h"
 #include "LockedFile.h"
 #include "MetadataHelper.h"
 #include "mozilla/dom/FileHandleBinding.h"
 using namespace mozilla;
 using namespace mozilla::dom;
 USING_FILE_NAMESPACE
 namespace {
 class GetFileHelper : public MetadataHelper
 {
 public:
   GetFileHelper(LockedFile* aLockedFile,
                 FileRequest* aFileRequest,
                 MetadataParameters* aParams,
                 FileHandle* aFileHandle)
   : MetadataHelper(aLockedFile, aFileRequest, aParams),
     mFileHandle(aFileHandle)
   { }
   virtual nsresult
   GetSuccessResult(JSContext* aCx,
                    JS::MutableHandle<JS::Value> aVal) MOZ_OVERRIDE;
   virtual void
   ReleaseObjects() MOZ_OVERRIDE
   {
     mFileHandle = nullptr;
     MetadataHelper::ReleaseObjects();
   }
 private:
   nsRefPtr<FileHandle> mFileHandle;
 };
 } // anonymous namespace
 NS_IMPL_CYCLE_COLLECTION_INHERITED(FileHandle, DOMEventTargetHelper,
                                    mFileStorage)
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(FileHandle)
 NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
 NS_IMPL_ADDREF_INHERITED(FileHandle, DOMEventTargetHelper)
 NS_IMPL_RELEASE_INHERITED(FileHandle, DOMEventTargetHelper)
 // static
 already_AddRefed<FileHandle>
 FileHandle::Create(nsPIDOMWindow* aWindow,
                    nsIFileStorage* aFileStorage,
                    nsIFile* aFile)
 {
   MOZ_ASSERT(NS_IsMainThread(), "Wrong thread!");
   nsRefPtr<FileHandle> newFileHandle = new FileHandle(aWindow);
   newFileHandle->mFileStorage = aFileStorage;
   nsresult rv = aFile->GetLeafName(newFileHandle->mName);
   if (NS_WARN_IF(NS_FAILED(rv))) {
     return nullptr;
   }
   newFileHandle->mFile = aFile;
   newFileHandle->mFileName = newFileHandle->mName;
   return newFileHandle.forget();
 }
 // virtual
 already_AddRefed<nsISupports>
 FileHandle::CreateStream(nsIFile* aFile, bool aReadOnly)
 {
   nsresult rv;
   if (aReadOnly) {
     nsCOMPtr<nsIInputStream> stream;
     rv = NS_NewLocalFileInputStream(getter_AddRefs(stream), aFile, -1, -1,
                                     nsIFileInputStream::DEFER_OPEN);
     if (NS_WARN_IF(NS_FAILED(rv))) {
       return nullptr;
     }
     return stream.forget();
   }
   nsCOMPtr<nsIFileStream> stream;
   rv = NS_NewLocalFileStream(getter_AddRefs(stream), aFile, -1, -1,
                              nsIFileStream::DEFER_OPEN);
   if (NS_WARN_IF(NS_FAILED(rv))) {
     return nullptr;
   }
   return stream.forget();
 }
 // virtual
 already_AddRefed<nsIDOMFile>
 FileHandle::CreateFileObject(LockedFile* aLockedFile, uint32_t aFileSize)
 {
   nsCOMPtr<nsIDOMFile> file =
     new File(mName, mType, aFileSize, mFile, aLockedFile);
   return file.forget();
 }
 // virtual
 JSObject*
 FileHandle::WrapObject(JSContext* aCx)
 {
   return FileHandleBinding::Wrap(aCx, this);
 }
 already_AddRefed<LockedFile>
 FileHandle::Open(FileMode aMode, ErrorResult& aError)
 {
   MOZ_ASSERT(NS_IsMainThread());
   if (FileService::IsShuttingDown() || mFileStorage->IsShuttingDown()) {
     aError.Throw(NS_ERROR_DOM_FILEHANDLE_UNKNOWN_ERR);
     return nullptr;
   }
   nsRefPtr<LockedFile> lockedFile = LockedFile::Create(this, aMode);
   if (!lockedFile) {
     aError.Throw(NS_ERROR_DOM_FILEHANDLE_UNKNOWN_ERR);
     return nullptr;
   }
   return lockedFile.forget();
 }
 already_AddRefed<DOMRequest>
 FileHandle::GetFile(ErrorResult& aError)
 {
   MOZ_ASSERT(NS_IsMainThread());
   // Do nothing if the window is closed
   if (!GetOwner()) {
     return nullptr;
   }
   nsRefPtr<LockedFile> lockedFile =
     LockedFile::Create(this, FileMode::Readonly, LockedFile::PARALLEL);
   if (!lockedFile) {
     aError.Throw(NS_ERROR_DOM_FILEHANDLE_UNKNOWN_ERR);
     return nullptr;
   }
   nsRefPtr<FileRequest> request =
     FileRequest::Create(GetOwner(), lockedFile, /* aWrapAsDOMRequest */ true);
   nsRefPtr<MetadataParameters> params = new MetadataParameters(true, false);
   nsRefPtr<GetFileHelper> helper =
     new GetFileHelper(lockedFile, request, params, this);
   nsresult rv = helper->Enqueue();
   if (NS_FAILED(rv)) {
     aError.Throw(NS_ERROR_DOM_FILEHANDLE_UNKNOWN_ERR);
     return nullptr;
   }
   return request.forget();
 }
 nsresult
 GetFileHelper::GetSuccessResult(JSContext* aCx,
                                 JS::MutableHandle<JS::Value> aVal)
 {
   nsCOMPtr<nsIDOMFile> domFile =
     mFileHandle->CreateFileObject(mLockedFile, mParams->Size());
   nsresult rv =
     nsContentUtils::WrapNative(aCx, domFile, &NS_GET_IID(nsIDOMFile), aVal);
   NS_ENSURE_SUCCESS(rv, NS_ERROR_DOM_FILEHANDLE_UNKNOWN_ERR);
   return NS_OK;
 }

The Tor Browser / annotate

dom/file/FileHandle.cpp@ac0c01689b40 (annotated)

dom/file/FileHandle.cpp