content/base/src/nsDOMFile.cpp
author David Anderson <danderson@mozilla.com>
Wed, 15 Aug 2012 14:22:26 -0700
changeset 112986 dc5fc4265990c8ecb269195372959f757af7d00e
parent 112929 b8084b0700fa586f1208dfe58076d1cb7cff2edc
parent 107762 a1cb80516a0061cc0e0e3312e93b6a2585689367
child 112990 d1b17b12a472efd78831ef9f6b9f331c96c438b0
permissions -rw-r--r--
Merge from mozilla-central.

/* -*- 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 "nsDOMFile.h"

#include "nsCExternalHandlerService.h"
#include "nsContentCID.h"
#include "nsContentUtils.h"
#include "nsDOMClassInfoID.h"
#include "nsError.h"
#include "nsICharsetDetector.h"
#include "nsICharsetConverterManager.h"
#include "nsIClassInfo.h"
#include "nsIConverterInputStream.h"
#include "nsIDocument.h"
#include "nsIFileStreams.h"
#include "nsIInputStream.h"
#include "nsIIPCSerializable.h"
#include "nsIMIMEService.h"
#include "nsIPlatformCharset.h"
#include "nsISeekableStream.h"
#include "nsIUnicharInputStream.h"
#include "nsIUnicodeDecoder.h"
#include "nsNetCID.h"
#include "nsNetUtil.h"
#include "nsIUUIDGenerator.h"
#include "nsBlobProtocolHandler.h"
#include "nsStringStream.h"
#include "nsJSUtils.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/Preferences.h"
#include "mozilla/Attributes.h"

#include "plbase64.h"
#include "prmem.h"
#include "dombindings.h"

using namespace mozilla;
using namespace mozilla::dom;

// XXXkhuey the input stream that we pass out of a DOMFile
// can outlive the actual DOMFile object.  Thus, we must
// ensure that the buffer underlying the stream we get
// from NS_NewByteInputStream is held alive as long as the
// stream is.  We do that by passing back this class instead.
class DataOwnerAdapter MOZ_FINAL : public nsIInputStream,
                                   public nsISeekableStream,
                                   public nsIIPCSerializable,
                                   public nsIClassInfo
{
  typedef nsDOMMemoryFile::DataOwner DataOwner;
public:
  static nsresult Create(DataOwner* aDataOwner,
                         PRUint32 aStart,
                         PRUint32 aLength,
                         nsIInputStream** _retval);

  NS_DECL_ISUPPORTS

  // These are mandatory.
  NS_FORWARD_NSIINPUTSTREAM(mStream->)
  NS_FORWARD_NSISEEKABLESTREAM(mSeekableStream->)

  // These are optional. We use a conditional QI to keep them from being called
  // if the underlying stream doesn't QI to either interface.
  NS_FORWARD_NSIIPCSERIALIZABLE(mSerializable->)
  NS_FORWARD_NSICLASSINFO(mClassInfo->)

private:
  DataOwnerAdapter(DataOwner* aDataOwner,
                   nsIInputStream* aStream)
    : mDataOwner(aDataOwner), mStream(aStream),
      mSeekableStream(do_QueryInterface(aStream)),
      mSerializable(do_QueryInterface(aStream)),
      mClassInfo(do_QueryInterface(aStream))
  {
    NS_ASSERTION(mSeekableStream, "Somebody gave us the wrong stream!");
  }

  nsRefPtr<DataOwner> mDataOwner;
  nsCOMPtr<nsIInputStream> mStream;
  nsCOMPtr<nsISeekableStream> mSeekableStream;
  nsCOMPtr<nsIIPCSerializable> mSerializable;
  nsCOMPtr<nsIClassInfo> mClassInfo;
};

NS_IMPL_THREADSAFE_ADDREF(DataOwnerAdapter)
NS_IMPL_THREADSAFE_RELEASE(DataOwnerAdapter)

NS_INTERFACE_MAP_BEGIN(DataOwnerAdapter)
  NS_INTERFACE_MAP_ENTRY(nsIInputStream)
  NS_INTERFACE_MAP_ENTRY(nsISeekableStream)
  NS_INTERFACE_MAP_ENTRY_CONDITIONAL(nsIIPCSerializable, mSerializable)
  NS_INTERFACE_MAP_ENTRY_CONDITIONAL(nsIClassInfo, mClassInfo)
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIInputStream)
NS_INTERFACE_MAP_END

nsresult DataOwnerAdapter::Create(DataOwner* aDataOwner,
                                  PRUint32 aStart,
                                  PRUint32 aLength,
                                  nsIInputStream** _retval)
{
  nsresult rv;
  NS_ASSERTION(aDataOwner, "Uh ...");

  nsCOMPtr<nsIInputStream> stream;

  rv = NS_NewByteInputStream(getter_AddRefs(stream),
                             static_cast<const char*>(aDataOwner->mData) +
                             aStart,
                             (PRInt32)aLength,
                             NS_ASSIGNMENT_DEPEND);
  NS_ENSURE_SUCCESS(rv, rv);

  NS_ADDREF(*_retval = new DataOwnerAdapter(aDataOwner, stream));

  return NS_OK;
}

////////////////////////////////////////////////////////////////////////////
// nsDOMFileBase implementation

NS_IMETHODIMP
nsDOMFileBase::GetName(nsAString &aFileName)
{
  NS_ASSERTION(mIsFile, "Should only be called on files");
  aFileName = mName;
  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileBase::GetLastModifiedDate(JSContext* cx, JS::Value *aLastModifiedDate)
{
  aLastModifiedDate->setNull();
  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileBase::GetMozFullPath(nsAString &aFileName)
{
  NS_ASSERTION(mIsFile, "Should only be called on files");

  // It is unsafe to call CallerHasUniversalXPConnect on a non-main thread. If
  // you hit the following assertion you need to figure out some other way to
  // determine privileges and call GetMozFullPathInternal.
  NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");

  if (nsContentUtils::CallerHasUniversalXPConnect()) {
    return GetMozFullPathInternal(aFileName);
  }
  aFileName.Truncate();
  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileBase::GetMozFullPathInternal(nsAString &aFileName)
{
  NS_ASSERTION(mIsFile, "Should only be called on files");
  aFileName.Truncate();
  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileBase::GetSize(PRUint64 *aSize)
{
  *aSize = mLength;
  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileBase::GetType(nsAString &aType)
{
  aType = mContentType;
  return NS_OK;
}

// Makes sure that aStart and aEnd is less then or equal to aSize and greater
// than 0
static void
ParseSize(PRInt64 aSize, PRInt64& aStart, PRInt64& aEnd)
{
  CheckedInt64 newStartOffset = aStart;
  if (aStart < -aSize) {
    newStartOffset = 0;
  }
  else if (aStart < 0) {
    newStartOffset += aSize;
  }
  else if (aStart > aSize) {
    newStartOffset = aSize;
  }

  CheckedInt64 newEndOffset = aEnd;
  if (aEnd < -aSize) {
    newEndOffset = 0;
  }
  else if (aEnd < 0) {
    newEndOffset += aSize;
  }
  else if (aEnd > aSize) {
    newEndOffset = aSize;
  }

  if (!newStartOffset.isValid() || !newEndOffset.isValid() ||
      newStartOffset.value() >= newEndOffset.value()) {
    aStart = aEnd = 0;
  }
  else {
    aStart = newStartOffset.value();
    aEnd = newEndOffset.value();
  }
}

NS_IMETHODIMP
nsDOMFileBase::Slice(PRInt64 aStart, PRInt64 aEnd,
                     const nsAString& aContentType, PRUint8 optional_argc,
                     nsIDOMBlob **aBlob)
{
  *aBlob = nullptr;

  // Truncate aStart and aEnd so that we stay within this file.
  PRUint64 thisLength;
  nsresult rv = GetSize(&thisLength);
  NS_ENSURE_SUCCESS(rv, rv);

  if (optional_argc < 2) {
    aEnd = (PRInt64)thisLength;
  }

  ParseSize((PRInt64)thisLength, aStart, aEnd);
  
  // Create the new file
  *aBlob = CreateSlice((PRUint64)aStart, (PRUint64)(aEnd - aStart),
                       aContentType).get();

  return *aBlob ? NS_OK : NS_ERROR_UNEXPECTED;
}

NS_IMETHODIMP
nsDOMFileBase::MozSlice(PRInt64 aStart, PRInt64 aEnd,
                        const nsAString& aContentType, 
                        JSContext* aCx,
                        PRUint8 optional_argc,
                        nsIDOMBlob **aBlob)
{
  MOZ_ASSERT(NS_IsMainThread());

  nsIScriptGlobalObject* sgo = nsJSUtils::GetDynamicScriptGlobal(aCx);
  if (sgo) {
    nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(sgo);
    if (window) {
      nsCOMPtr<nsIDocument> document =
        do_QueryInterface(window->GetExtantDocument());
      if (document) {
        document->WarnOnceAbout(nsIDocument::eMozSlice);
      }
    }
  }

  return Slice(aStart, aEnd, aContentType, optional_argc, aBlob);
}

NS_IMETHODIMP
nsDOMFileBase::GetInternalStream(nsIInputStream **aStream)
{
  // Must be overridden
  NS_NOTREACHED("Must override GetInternalStream");
  
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
nsDOMFileBase::GetInternalUrl(nsIPrincipal* aPrincipal, nsAString& aURL)
{
  NS_ENSURE_STATE(aPrincipal);

  nsresult rv;
  nsCOMPtr<nsIUUIDGenerator> uuidgen =
    do_GetService("@mozilla.org/uuid-generator;1", &rv);
  NS_ENSURE_SUCCESS(rv, rv);
  
  nsID id;
  rv = uuidgen->GenerateUUIDInPlace(&id);
  NS_ENSURE_SUCCESS(rv, rv);
  
  char chars[NSID_LENGTH];
  id.ToProvidedString(chars);
    
  nsCString url = NS_LITERAL_CSTRING(BLOBURI_SCHEME ":") +
    Substring(chars + 1, chars + NSID_LENGTH - 2);

  nsBlobProtocolHandler::AddFileDataEntry(url, this,
                                              aPrincipal);

  CopyASCIItoUTF16(url, aURL);
  
  return NS_OK;
}

NS_IMETHODIMP_(PRInt64)
nsDOMFileBase::GetFileId()
{
  PRInt64 id = -1;

  if (IsStoredFile() && IsWholeFile() && !IsSnapshot()) {
    if (!indexedDB::IndexedDatabaseManager::IsClosed()) {
      indexedDB::IndexedDatabaseManager::FileMutex().Lock();
    }

    NS_ASSERTION(!mFileInfos.IsEmpty(),
                 "A stored file must have at least one file info!");

    nsRefPtr<indexedDB::FileInfo>& fileInfo = mFileInfos.ElementAt(0);
    if (fileInfo) {
      id =  fileInfo->Id();
    }

    if (!indexedDB::IndexedDatabaseManager::IsClosed()) {
      indexedDB::IndexedDatabaseManager::FileMutex().Unlock();
    }
  }

  return id;
}

NS_IMETHODIMP_(void)
nsDOMFileBase::AddFileInfo(indexedDB::FileInfo* aFileInfo)
{
  if (indexedDB::IndexedDatabaseManager::IsClosed()) {
    NS_ERROR("Shouldn't be called after shutdown!");
    return;
  }

  nsRefPtr<indexedDB::FileInfo> fileInfo = aFileInfo;

  MutexAutoLock lock(indexedDB::IndexedDatabaseManager::FileMutex());

  NS_ASSERTION(!mFileInfos.Contains(aFileInfo),
               "Adding the same file info agan?!");

  nsRefPtr<indexedDB::FileInfo>* element = mFileInfos.AppendElement();
  element->swap(fileInfo);
}

NS_IMETHODIMP_(indexedDB::FileInfo*)
nsDOMFileBase::GetFileInfo(indexedDB::FileManager* aFileManager)
{
  if (indexedDB::IndexedDatabaseManager::IsClosed()) {
    NS_ERROR("Shouldn't be called after shutdown!");
    return nullptr;
  }

  // A slice created from a stored file must keep the file info alive.
  // However, we don't support sharing of slices yet, so the slice must be
  // copied again. That's why we have to ignore the first file info.
  // Snapshots are handled in a similar way (they have to be copied).
  PRUint32 startIndex;
  if (IsStoredFile() && (!IsWholeFile() || IsSnapshot())) {
    startIndex = 1;
  }
  else {
    startIndex = 0;
  }

  MutexAutoLock lock(indexedDB::IndexedDatabaseManager::FileMutex());

  for (PRUint32 i = startIndex; i < mFileInfos.Length(); i++) {
    nsRefPtr<indexedDB::FileInfo>& fileInfo = mFileInfos.ElementAt(i);
    if (fileInfo->Manager() == aFileManager) {
      return fileInfo;
    }
  }

  return nullptr;
}

NS_IMETHODIMP
nsDOMFileBase::GetSendInfo(nsIInputStream** aBody,
                           nsACString& aContentType,
                           nsACString& aCharset)
{
  nsresult rv;

  nsCOMPtr<nsIInputStream> stream;
  rv = this->GetInternalStream(getter_AddRefs(stream));
  NS_ENSURE_SUCCESS(rv, rv);

  nsString contentType;
  rv = this->GetType(contentType);
  NS_ENSURE_SUCCESS(rv, rv);

  CopyUTF16toUTF8(contentType, aContentType);

  aCharset.Truncate();

  stream.forget(aBody);
  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileBase::GetMutable(bool* aMutable)
{
  *aMutable = !mImmutable;
  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileBase::SetMutable(bool aMutable)
{
  nsresult rv = NS_OK;

  NS_ENSURE_ARG(!mImmutable || !aMutable);

  if (!mImmutable && !aMutable) {
    // Force the content type and size to be cached
    nsString dummyString;
    rv = this->GetType(dummyString);
    NS_ENSURE_SUCCESS(rv, rv);

    PRUint64 dummyInt;
    rv = this->GetSize(&dummyInt);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  mImmutable = !aMutable;
  return rv;
}

////////////////////////////////////////////////////////////////////////////
// nsDOMFile implementation

DOMCI_DATA(File, nsDOMFile)
DOMCI_DATA(Blob, nsDOMFile)

NS_INTERFACE_MAP_BEGIN(nsDOMFile)
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIDOMFile)
  NS_INTERFACE_MAP_ENTRY(nsIDOMBlob)
  NS_INTERFACE_MAP_ENTRY_CONDITIONAL(nsIDOMFile, mIsFile)
  NS_INTERFACE_MAP_ENTRY(nsIXHRSendable)
  NS_INTERFACE_MAP_ENTRY(nsIMutable)
  NS_DOM_INTERFACE_MAP_ENTRY_CLASSINFO_CONDITIONAL(File, mIsFile)
  NS_DOM_INTERFACE_MAP_ENTRY_CLASSINFO_CONDITIONAL(Blob, !mIsFile)
NS_INTERFACE_MAP_END

// Threadsafe when GetMutable() == false
NS_IMPL_THREADSAFE_ADDREF(nsDOMFile)
NS_IMPL_THREADSAFE_RELEASE(nsDOMFile)

////////////////////////////////////////////////////////////////////////////
// nsDOMFileCC implementation

NS_IMPL_CYCLE_COLLECTION_0(nsDOMFileCC)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsDOMFileCC)
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIDOMFile)
  NS_INTERFACE_MAP_ENTRY(nsIDOMBlob)
  NS_INTERFACE_MAP_ENTRY_CONDITIONAL(nsIDOMFile, mIsFile)
  NS_INTERFACE_MAP_ENTRY(nsIXHRSendable)
  NS_INTERFACE_MAP_ENTRY(nsIMutable)
  NS_DOM_INTERFACE_MAP_ENTRY_CLASSINFO_CONDITIONAL(File, mIsFile)
  NS_DOM_INTERFACE_MAP_ENTRY_CLASSINFO_CONDITIONAL(Blob, !mIsFile)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTING_ADDREF(nsDOMFileCC)
NS_IMPL_CYCLE_COLLECTING_RELEASE(nsDOMFileCC)

////////////////////////////////////////////////////////////////////////////
// nsDOMFileFile implementation

NS_IMPL_ISUPPORTS_INHERITED1(nsDOMFileFile, nsDOMFile,
                             nsIJSNativeInitializer)

already_AddRefed<nsIDOMBlob>
nsDOMFileFile::CreateSlice(PRUint64 aStart, PRUint64 aLength,
                           const nsAString& aContentType)
{
  nsCOMPtr<nsIDOMBlob> t = new nsDOMFileFile(this, aStart, aLength, aContentType);
  return t.forget();
}

/* static */ nsresult
nsDOMFileFile::NewFile(nsISupports* *aNewObject)
{
  nsCOMPtr<nsISupports> file = do_QueryObject(new nsDOMFileFile());
  file.forget(aNewObject);
  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileFile::GetMozFullPathInternal(nsAString &aFilename)
{
  NS_ASSERTION(mIsFile, "Should only be called on files");
  return mFile->GetPath(aFilename);
}

NS_IMETHODIMP
nsDOMFileFile::GetLastModifiedDate(JSContext* cx, JS::Value *aLastModifiedDate)
{
  PRInt64 msecs;
  mFile->GetLastModifiedTime(&msecs);
  JSObject* date = JS_NewDateObjectMsec(cx, msecs);
  if (date) {
    aLastModifiedDate->setObject(*date);
  }
  else {
    aLastModifiedDate->setNull();
  }

  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileFile::GetSize(PRUint64 *aFileSize)
{
  if (IsSizeUnknown()) {
    NS_ASSERTION(mWholeFile,
                 "Should only use lazy size when using the whole file");
    PRInt64 fileSize;
    nsresult rv = mFile->GetFileSize(&fileSize);
    NS_ENSURE_SUCCESS(rv, rv);
  
    if (fileSize < 0) {
      return NS_ERROR_FAILURE;
    }
  
    mLength = fileSize;
  }

  *aFileSize = mLength;

  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileFile::GetType(nsAString &aType)
{
  if (mContentType.IsVoid()) {
    NS_ASSERTION(mWholeFile,
                 "Should only use lazy ContentType when using the whole file");
    nsresult rv;
    nsCOMPtr<nsIMIMEService> mimeService =
      do_GetService(NS_MIMESERVICE_CONTRACTID, &rv);
    NS_ENSURE_SUCCESS(rv, rv);

    nsCAutoString mimeType;
    rv = mimeService->GetTypeFromFile(mFile, mimeType);
    if (NS_FAILED(rv)) {
      mimeType.Truncate();
    }

    AppendUTF8toUTF16(mimeType, mContentType);
    mContentType.SetIsVoid(false);
  }

  aType = mContentType;

  return NS_OK;
}

const PRUint32 sFileStreamFlags =
  nsIFileInputStream::CLOSE_ON_EOF |
  nsIFileInputStream::REOPEN_ON_REWIND |
  nsIFileInputStream::DEFER_OPEN;

NS_IMETHODIMP
nsDOMFileFile::GetInternalStream(nsIInputStream **aStream)
{
  return mWholeFile ?
    NS_NewLocalFileInputStream(aStream, mFile, -1, -1, sFileStreamFlags) :
    NS_NewPartialLocalFileInputStream(aStream, mFile, mStart, mLength,
                                      -1, -1, sFileStreamFlags);
}

NS_IMETHODIMP
nsDOMFileFile::Initialize(nsISupports* aOwner,
                          JSContext* aCx,
                          JSObject* aObj,
                          PRUint32 aArgc,
                          JS::Value* aArgv)
{
  nsresult rv;

  NS_ASSERTION(!mImmutable, "Something went wrong ...");
  NS_ENSURE_TRUE(!mImmutable, NS_ERROR_UNEXPECTED);

  if (!nsContentUtils::IsCallerChrome()) {
    return NS_ERROR_DOM_SECURITY_ERR; // Real short trip
  }

  NS_ENSURE_TRUE(aArgc > 0, NS_ERROR_UNEXPECTED);

  // We expect to get a path to represent as a File object,
  // or an nsIFile
  nsCOMPtr<nsIFile> file;
  if (!aArgv[0].isString()) {
    // Lets see if it's an nsIFile
    if (!aArgv[0].isObject()) {
      return NS_ERROR_UNEXPECTED; // We're not interested
    }

    JSObject* obj = &aArgv[0].toObject();

    // Is it an nsIFile
    file = do_QueryInterface(
      nsContentUtils::XPConnect()->
        GetNativeOfWrapper(aCx, obj));
    if (!file)
      return NS_ERROR_UNEXPECTED;
  } else {
    // It's a string
    JSString* str = JS_ValueToString(aCx, aArgv[0]);
    NS_ENSURE_TRUE(str, NS_ERROR_XPC_BAD_CONVERT_JS);

    nsDependentJSString xpcomStr;
    if (!xpcomStr.init(aCx, str)) {
      return NS_ERROR_XPC_BAD_CONVERT_JS;
    }

    rv = NS_NewLocalFile(xpcomStr, false, getter_AddRefs(file));
    NS_ENSURE_SUCCESS(rv, rv);
  }

  bool exists;
  rv = file->Exists(&exists);
  NS_ENSURE_SUCCESS(rv, rv);
  NS_ENSURE_TRUE(exists, NS_ERROR_FILE_NOT_FOUND);

  bool isDir;
  rv = file->IsDirectory(&isDir);
  NS_ENSURE_SUCCESS(rv, rv);
  NS_ENSURE_FALSE(isDir, NS_ERROR_FILE_IS_DIRECTORY);

  mFile = file;
  file->GetLeafName(mName);

  return NS_OK;
}

////////////////////////////////////////////////////////////////////////////
// nsDOMMemoryFile implementation

already_AddRefed<nsIDOMBlob>
nsDOMMemoryFile::CreateSlice(PRUint64 aStart, PRUint64 aLength,
                             const nsAString& aContentType)
{
  nsCOMPtr<nsIDOMBlob> t =
    new nsDOMMemoryFile(this, aStart, aLength, aContentType);
  return t.forget();
}

NS_IMETHODIMP
nsDOMMemoryFile::GetInternalStream(nsIInputStream **aStream)
{
  if (mLength > PR_INT32_MAX)
    return NS_ERROR_FAILURE;

  return DataOwnerAdapter::Create(mDataOwner, mStart, mLength, aStream);
}

////////////////////////////////////////////////////////////////////////////
// nsDOMFileList implementation

DOMCI_DATA(FileList, nsDOMFileList)

NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_0(nsDOMFileList)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsDOMFileList)
  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIDOMFileList)
  NS_INTERFACE_MAP_ENTRY(nsIDOMFileList)
  NS_DOM_INTERFACE_MAP_ENTRY_CLASSINFO(FileList)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTING_ADDREF(nsDOMFileList)
NS_IMPL_CYCLE_COLLECTING_RELEASE(nsDOMFileList)

JSObject*
nsDOMFileList::WrapObject(JSContext *cx, JSObject *scope,
                          bool *triedToWrap)
{
  return mozilla::dom::binding::FileList::create(cx, scope, this, triedToWrap);
}

nsIDOMFile*
nsDOMFileList::GetItemAt(PRUint32 aIndex)
{
  return mFiles.SafeObjectAt(aIndex);
}

NS_IMETHODIMP
nsDOMFileList::GetLength(PRUint32* aLength)
{
  *aLength = mFiles.Count();

  return NS_OK;
}

NS_IMETHODIMP
nsDOMFileList::Item(PRUint32 aIndex, nsIDOMFile **aFile)
{
  NS_IF_ADDREF(*aFile = nsDOMFileList::GetItemAt(aIndex));

  return NS_OK;
}

////////////////////////////////////////////////////////////////////////////
// nsDOMFileInternalUrlHolder implementation

nsDOMFileInternalUrlHolder::nsDOMFileInternalUrlHolder(nsIDOMBlob* aFile,
                                                       nsIPrincipal* aPrincipal
                                                       MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL) {
  MOZ_GUARD_OBJECT_NOTIFIER_INIT;
  aFile->GetInternalUrl(aPrincipal, mUrl);
}
 
nsDOMFileInternalUrlHolder::~nsDOMFileInternalUrlHolder() {
  if (!mUrl.IsEmpty()) {
    nsCAutoString narrowUrl;
    CopyUTF16toUTF8(mUrl, narrowUrl);
    nsBlobProtocolHandler::RemoveFileDataEntry(narrowUrl);
  }
}