tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

CompressionStream.cpp (3825B)

      1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
      2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
      3 /* This Source Code Form is subject to the terms of the Mozilla Public
      4 * License, v. 2.0. If a copy of the MPL was not distributed with this
      5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      6 
      7 #include "mozilla/dom/CompressionStream.h"
      8 
      9 #include "FormatBrotli.h"
     10 #include "FormatZlib.h"
     11 #include "js/TypeDecls.h"
     12 #include "mozilla/dom/CompressionStreamBinding.h"
     13 #include "mozilla/dom/ReadableStream.h"
     14 #include "mozilla/dom/TextDecoderStream.h"
     15 #include "mozilla/dom/TransformStream.h"
     16 #include "mozilla/dom/WritableStream.h"
     17 
     18 // See the zlib manual in https://www.zlib.net/manual.html or in
     19 // https://searchfox.org/mozilla-central/source/modules/zlib/src/zlib.h
     20 
     21 namespace mozilla::dom {
     22 using namespace compression;
     23 
     24 NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(CompressionStream, mGlobal, mStream)
     25 NS_IMPL_CYCLE_COLLECTING_ADDREF(CompressionStream)
     26 NS_IMPL_CYCLE_COLLECTING_RELEASE(CompressionStream)
     27 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(CompressionStream)
     28  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
     29  NS_INTERFACE_MAP_ENTRY(nsISupports)
     30 NS_INTERFACE_MAP_END
     31 
     32 /*
     33 * Constructs either a ZLibDecompressionStreamAlgorithms or a
     34 * BrotliDecompressionStreamAlgorithms, based on the CompressionFormat.
     35 */
     36 static Result<already_AddRefed<CompressionStreamAlgorithms>, nsresult>
     37 CreateCompressionStreamAlgorithms(CompressionFormat aFormat) {
     38  if (aFormat == CompressionFormat::Brotli) {
     39    RefPtr<CompressionStreamAlgorithms> brotliAlgos =
     40        MOZ_TRY(BrotliCompressionStreamAlgorithms::Create());
     41    return brotliAlgos.forget();
     42  }
     43 
     44  RefPtr<CompressionStreamAlgorithms> zlibAlgos =
     45      MOZ_TRY(ZLibCompressionStreamAlgorithms::Create(aFormat));
     46  return zlibAlgos.forget();
     47 }
     48 
     49 CompressionStream::CompressionStream(nsISupports* aGlobal,
     50                                     TransformStream& aStream)
     51    : mGlobal(aGlobal), mStream(&aStream) {}
     52 
     53 CompressionStream::~CompressionStream() = default;
     54 
     55 JSObject* CompressionStream::WrapObject(JSContext* aCx,
     56                                        JS::Handle<JSObject*> aGivenProto) {
     57  return CompressionStream_Binding::Wrap(aCx, this, aGivenProto);
     58 }
     59 
     60 // https://wicg.github.io/compression/#dom-compressionstream-compressionstream
     61 already_AddRefed<CompressionStream> CompressionStream::Constructor(
     62    const GlobalObject& aGlobal, CompressionFormat aFormat, ErrorResult& aRv) {
     63  if (aFormat == CompressionFormat::Zstd) {
     64    aRv.ThrowTypeError(
     65        "'zstd' (value of argument 1) is not a valid value for enumeration "
     66        "CompressionFormat.");
     67    return nullptr;
     68  }
     69 
     70  // Step 1: If format is unsupported in CompressionStream, then throw a
     71  // TypeError.
     72  // XXX: Skipped as we are using enum for this
     73 
     74  // Step 2 - 4: (Done in CompressionStreamAlgorithms)
     75 
     76  // Step 5: Set this's transform to a new TransformStream.
     77 
     78  // Step 6: Set up this's transform with transformAlgorithm set to
     79  // transformAlgorithm and flushAlgorithm set to flushAlgorithm.
     80  Result<already_AddRefed<CompressionStreamAlgorithms>, nsresult> algorithms =
     81      CreateCompressionStreamAlgorithms(aFormat);
     82  if (algorithms.isErr()) {
     83    aRv.ThrowUnknownError("Not enough memory");
     84    return nullptr;
     85  }
     86 
     87  RefPtr<CompressionStreamAlgorithms> alg = algorithms.unwrap();
     88  RefPtr<TransformStream> stream =
     89      TransformStream::CreateGeneric(aGlobal, *alg, aRv);
     90  if (aRv.Failed()) {
     91    return nullptr;
     92  }
     93  return do_AddRef(new CompressionStream(aGlobal.GetAsSupports(), *stream));
     94 }
     95 
     96 already_AddRefed<ReadableStream> CompressionStream::Readable() const {
     97  return do_AddRef(mStream->Readable());
     98 }
     99 
    100 already_AddRefed<WritableStream> CompressionStream::Writable() const {
    101  return do_AddRef(mStream->Writable());
    102 }
    103 
    104 }  // namespace mozilla::dom