1 files changed, 480 insertions, 0 deletions
diff --git a/dom/media/webaudio/AudioBuffer.cpp b/dom/media/webaudio/AudioBuffer.cpp
new file mode 100644
index 0000000000..03e70567b9
--- /dev/null
+++ b/dom/media/webaudio/AudioBuffer.cpp
@@ -0,0 +1,480 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 "AudioBuffer.h"
+#include "mozilla/dom/AudioBufferBinding.h"
+#include "jsfriendapi.h"
+#include "js/ArrayBuffer.h"             // JS::StealArrayBufferContents
+#include "js/experimental/TypedData.h"  // JS_NewFloat32Array, JS_GetFloat32ArrayData, JS_GetTypedArrayLength, JS_GetArrayBufferViewBuffer
+#include "mozilla/ErrorResult.h"
+#include "AudioSegment.h"
+#include "AudioChannelFormat.h"
+#include "mozilla/PodOperations.h"
+#include "mozilla/CheckedInt.h"
+#include "mozilla/HoldDropJSObjects.h"
+#include "mozilla/MemoryReporting.h"
+#include "AudioNodeEngine.h"
+#include "nsPrintfCString.h"
+#include "nsTHashSet.h"
+#include <numeric>
+
+namespace mozilla::dom {
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(AudioBuffer)
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(AudioBuffer)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mJSChannels)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
+  tmp->ClearJSChannels();
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(AudioBuffer)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(AudioBuffer)
+  NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
+  for (uint32_t i = 0; i < tmp->mJSChannels.Length(); ++i) {
+    NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mJSChannels[i])
+  }
+NS_IMPL_CYCLE_COLLECTION_TRACE_END
+
+/**
+ * AudioBuffers can be shared between AudioContexts, so we need a separate
+ * mechanism to track their memory usage. This thread-safe class keeps track of
+ * all the AudioBuffers, and gets called back by the memory reporting system
+ * when a memory report is needed, reporting how much memory is used by the
+ * buffers backing AudioBuffer objects. */
+class AudioBufferMemoryTracker : public nsIMemoryReporter {
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIMEMORYREPORTER
+
+ private:
+  AudioBufferMemoryTracker();
+  virtual ~AudioBufferMemoryTracker();
+
+ public:
+  /* Those methods can be called on any thread. */
+  static void RegisterAudioBuffer(const AudioBuffer* aAudioBuffer);
+  static void UnregisterAudioBuffer(const AudioBuffer* aAudioBuffer);
+
+ private:
+  static AudioBufferMemoryTracker* GetInstance();
+  /* Those methods must be called with the lock held. */
+  void RegisterAudioBufferInternal(const AudioBuffer* aAudioBuffer);
+  /* Returns the number of buffers still present in the hash table. */
+  uint32_t UnregisterAudioBufferInternal(const AudioBuffer* aAudioBuffer);
+  void Init();
+
+  /* This protects all members of this class. */
+  static StaticMutex sMutex MOZ_UNANNOTATED;
+  static StaticRefPtr<AudioBufferMemoryTracker> sSingleton;
+  nsTHashSet<const AudioBuffer*> mBuffers;
+};
+
+StaticRefPtr<AudioBufferMemoryTracker> AudioBufferMemoryTracker::sSingleton;
+StaticMutex AudioBufferMemoryTracker::sMutex;
+
+NS_IMPL_ISUPPORTS(AudioBufferMemoryTracker, nsIMemoryReporter);
+
+AudioBufferMemoryTracker* AudioBufferMemoryTracker::GetInstance() {
+  sMutex.AssertCurrentThreadOwns();
+  if (!sSingleton) {
+    sSingleton = new AudioBufferMemoryTracker();
+    sSingleton->Init();
+  }
+  return sSingleton;
+}
+
+AudioBufferMemoryTracker::AudioBufferMemoryTracker() = default;
+
+void AudioBufferMemoryTracker::Init() { RegisterWeakMemoryReporter(this); }
+
+AudioBufferMemoryTracker::~AudioBufferMemoryTracker() {
+  UnregisterWeakMemoryReporter(this);
+}
+
+void AudioBufferMemoryTracker::RegisterAudioBuffer(
+    const AudioBuffer* aAudioBuffer) {
+  StaticMutexAutoLock lock(sMutex);
+  AudioBufferMemoryTracker* tracker = AudioBufferMemoryTracker::GetInstance();
+  tracker->RegisterAudioBufferInternal(aAudioBuffer);
+}
+
+void AudioBufferMemoryTracker::UnregisterAudioBuffer(
+    const AudioBuffer* aAudioBuffer) {
+  StaticMutexAutoLock lock(sMutex);
+  AudioBufferMemoryTracker* tracker = AudioBufferMemoryTracker::GetInstance();
+  uint32_t count;
+  count = tracker->UnregisterAudioBufferInternal(aAudioBuffer);
+  if (count == 0) {
+    sSingleton = nullptr;
+  }
+}
+
+void AudioBufferMemoryTracker::RegisterAudioBufferInternal(
+    const AudioBuffer* aAudioBuffer) {
+  sMutex.AssertCurrentThreadOwns();
+  mBuffers.Insert(aAudioBuffer);
+}
+
+uint32_t AudioBufferMemoryTracker::UnregisterAudioBufferInternal(
+    const AudioBuffer* aAudioBuffer) {
+  sMutex.AssertCurrentThreadOwns();
+  mBuffers.Remove(aAudioBuffer);
+  return mBuffers.Count();
+}
+
+MOZ_DEFINE_MALLOC_SIZE_OF(AudioBufferMemoryTrackerMallocSizeOf)
+
+NS_IMETHODIMP
+AudioBufferMemoryTracker::CollectReports(nsIHandleReportCallback* aHandleReport,
+                                         nsISupports* aData, bool) {
+  StaticMutexAutoLock lock(sMutex);
+  const size_t amount =
+      std::accumulate(mBuffers.cbegin(), mBuffers.cend(), size_t(0),
+                      [](size_t val, const AudioBuffer* buffer) {
+                        return val + buffer->SizeOfIncludingThis(
+                                         AudioBufferMemoryTrackerMallocSizeOf);
+                      });
+
+  MOZ_COLLECT_REPORT("explicit/webaudio/audiobuffer", KIND_HEAP, UNITS_BYTES,
+                     amount, "Memory used by AudioBuffer objects (Web Audio).");
+
+  return NS_OK;
+}
+
+AudioBuffer::AudioBuffer(nsPIDOMWindowInner* aWindow,
+                         uint32_t aNumberOfChannels, uint32_t aLength,
+                         float aSampleRate, ErrorResult& aRv)
+    : mOwnerWindow(do_GetWeakReference(aWindow)), mSampleRate(aSampleRate) {
+  // Note that a buffer with zero channels is permitted here for the sake of
+  // AudioProcessingEvent, where channel counts must match parameters passed
+  // to createScriptProcessor(), one of which may be zero.
+  if (aSampleRate < WebAudioUtils::MinSampleRate ||
+      aSampleRate > WebAudioUtils::MaxSampleRate) {
+    aRv.ThrowNotSupportedError(
+        nsPrintfCString("Sample rate (%g) is out of range", aSampleRate));
+    return;
+  }
+
+  if (aNumberOfChannels > WebAudioUtils::MaxChannelCount) {
+    aRv.ThrowNotSupportedError(nsPrintfCString(
+        "Number of channels (%u) is out of range", aNumberOfChannels));
+    return;
+  }
+
+  if (!aLength || aLength > INT32_MAX) {
+    aRv.ThrowNotSupportedError(
+        nsPrintfCString("Length (%u) is out of range", aLength));
+    return;
+  }
+
+  mSharedChannels.mDuration = aLength;
+  mJSChannels.SetLength(aNumberOfChannels);
+  mozilla::HoldJSObjects(this);
+  AudioBufferMemoryTracker::RegisterAudioBuffer(this);
+}
+
+AudioBuffer::~AudioBuffer() {
+  AudioBufferMemoryTracker::UnregisterAudioBuffer(this);
+  ClearJSChannels();
+  mozilla::DropJSObjects(this);
+}
+
+/* static */
+already_AddRefed<AudioBuffer> AudioBuffer::Constructor(
+    const GlobalObject& aGlobal, const AudioBufferOptions& aOptions,
+    ErrorResult& aRv) {
+  if (!aOptions.mNumberOfChannels) {
+    aRv.ThrowNotSupportedError("Must have nonzero number of channels");
+    return nullptr;
+  }
+
+  nsCOMPtr<nsPIDOMWindowInner> window =
+      do_QueryInterface(aGlobal.GetAsSupports());
+
+  return Create(window, aOptions.mNumberOfChannels, aOptions.mLength,
+                aOptions.mSampleRate, aRv);
+}
+
+void AudioBuffer::ClearJSChannels() { mJSChannels.Clear(); }
+
+void AudioBuffer::SetSharedChannels(
+    already_AddRefed<ThreadSharedFloatArrayBufferList> aBuffer) {
+  RefPtr<ThreadSharedFloatArrayBufferList> buffer = aBuffer;
+  uint32_t channelCount = buffer->GetChannels();
+  mSharedChannels.mChannelData.SetLength(channelCount);
+  for (uint32_t i = 0; i < channelCount; ++i) {
+    mSharedChannels.mChannelData[i] = buffer->GetData(i);
+  }
+  mSharedChannels.mBuffer = std::move(buffer);
+  mSharedChannels.mBufferFormat = AUDIO_FORMAT_FLOAT32;
+}
+
+/* static */
+already_AddRefed<AudioBuffer> AudioBuffer::Create(
+    nsPIDOMWindowInner* aWindow, uint32_t aNumberOfChannels, uint32_t aLength,
+    float aSampleRate,
+    already_AddRefed<ThreadSharedFloatArrayBufferList> aInitialContents,
+    ErrorResult& aRv) {
+  RefPtr<ThreadSharedFloatArrayBufferList> initialContents = aInitialContents;
+  RefPtr<AudioBuffer> buffer =
+      new AudioBuffer(aWindow, aNumberOfChannels, aLength, aSampleRate, aRv);
+  if (aRv.Failed()) {
+    return nullptr;
+  }
+
+  if (initialContents) {
+    MOZ_ASSERT(initialContents->GetChannels() == aNumberOfChannels);
+    buffer->SetSharedChannels(initialContents.forget());
+  }
+
+  return buffer.forget();
+}
+
+/* static */
+already_AddRefed<AudioBuffer> AudioBuffer::Create(
+    nsPIDOMWindowInner* aWindow, float aSampleRate,
+    AudioChunk&& aInitialContents) {
+  AudioChunk initialContents = aInitialContents;
+  ErrorResult rv;
+  RefPtr<AudioBuffer> buffer =
+      new AudioBuffer(aWindow, initialContents.ChannelCount(),
+                      initialContents.mDuration, aSampleRate, rv);
+  if (rv.Failed()) {
+    return nullptr;
+  }
+  buffer->mSharedChannels = std::move(aInitialContents);
+
+  return buffer.forget();
+}
+
+JSObject* AudioBuffer::WrapObject(JSContext* aCx,
+                                  JS::Handle<JSObject*> aGivenProto) {
+  return AudioBuffer_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+static void CopyChannelDataToFloat(const AudioChunk& aChunk, uint32_t aChannel,
+                                   uint32_t aSrcOffset, float* aOutput,
+                                   uint32_t aLength) {
+  MOZ_ASSERT(aChunk.mVolume == 1.0f);
+  if (aChunk.mBufferFormat == AUDIO_FORMAT_FLOAT32) {
+    mozilla::PodCopy(
+        aOutput, aChunk.ChannelData<float>()[aChannel] + aSrcOffset, aLength);
+  } else {
+    MOZ_ASSERT(aChunk.mBufferFormat == AUDIO_FORMAT_S16);
+    ConvertAudioSamples(aChunk.ChannelData<int16_t>()[aChannel] + aSrcOffset,
+                        aOutput, aLength);
+  }
+}
+
+bool AudioBuffer::RestoreJSChannelData(JSContext* aJSContext) {
+  nsPIDOMWindowInner* global = GetParentObject();
+  if (!global || !global->AsGlobal()->HasJSGlobal()) {
+    return false;
+  }
+
+  JSAutoRealm ar(aJSContext, global->AsGlobal()->GetGlobalJSObject());
+
+  for (uint32_t i = 0; i < mJSChannels.Length(); ++i) {
+    if (mJSChannels[i]) {
+      // Already have data in JS array.
+      continue;
+    }
+
+    // The following code first zeroes the array and then copies our data
+    // into it. We could avoid this with additional JS APIs to construct
+    // an array (or ArrayBuffer) containing initial data.
+    JS::Rooted<JSObject*> array(aJSContext,
+                                JS_NewFloat32Array(aJSContext, Length()));
+    if (!array) {
+      return false;
+    }
+    if (!mSharedChannels.IsNull()) {
+      // "4. Attach ArrayBuffers containing copies of the data to the
+      // AudioBuffer, to be returned by the next call to getChannelData."
+      JS::AutoCheckCannotGC nogc;
+      bool isShared;
+      float* jsData = JS_GetFloat32ArrayData(array, &isShared, nogc);
+      MOZ_ASSERT(!isShared);  // Was created as unshared above
+      CopyChannelDataToFloat(mSharedChannels, i, 0, jsData, Length());
+    }
+    mJSChannels[i] = array;
+  }
+
+  mSharedChannels.SetNull(Length());
+
+  return true;
+}
+
+void AudioBuffer::CopyFromChannel(const Float32Array& aDestination,
+                                  uint32_t aChannelNumber,
+                                  uint32_t aBufferOffset, ErrorResult& aRv) {
+  if (aChannelNumber >= NumberOfChannels()) {
+    aRv.ThrowIndexSizeError(
+        nsPrintfCString("Channel number (%u) is out of range", aChannelNumber));
+    return;
+  }
+  uint32_t length = Length();
+  if (aBufferOffset >= length) {
+    return;
+  }
+  JS::AutoCheckCannotGC nogc;
+  aDestination.ComputeState();
+  uint32_t count = std::min(length - aBufferOffset, aDestination.Length());
+
+  JSObject* channelArray = mJSChannels[aChannelNumber];
+  if (channelArray) {
+    if (JS_GetTypedArrayLength(channelArray) != length) {
+      // The array's buffer was detached.
+      return;
+    }
+    bool isShared = false;
+    const float* sourceData =
+        JS_GetFloat32ArrayData(channelArray, &isShared, nogc);
+    // The sourceData arrays should all have originated in
+    // RestoreJSChannelData, where they are created unshared.
+    MOZ_ASSERT(!isShared);
+    PodMove(aDestination.Data(), sourceData + aBufferOffset, count);
+    return;
+  }
+
+  if (!mSharedChannels.IsNull()) {
+    CopyChannelDataToFloat(mSharedChannels, aChannelNumber, aBufferOffset,
+                           aDestination.Data(), count);
+    return;
+  }
+
+  PodZero(aDestination.Data(), count);
+}
+
+void AudioBuffer::CopyToChannel(JSContext* aJSContext,
+                                const Float32Array& aSource,
+                                uint32_t aChannelNumber, uint32_t aBufferOffset,
+                                ErrorResult& aRv) {
+  if (aChannelNumber >= NumberOfChannels()) {
+    aRv.ThrowIndexSizeError(
+        nsPrintfCString("Channel number (%u) is out of range", aChannelNumber));
+    return;
+  }
+
+  if (!RestoreJSChannelData(aJSContext)) {
+    aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
+    return;
+  }
+
+  JS::AutoCheckCannotGC nogc;
+  JSObject* channelArray = mJSChannels[aChannelNumber];
+  // This may differ from Length() if the buffer has been detached.
+  uint32_t length = JS_GetTypedArrayLength(channelArray);
+  if (aBufferOffset >= length) {
+    return;
+  }
+
+  aSource.ComputeState();
+  uint32_t count = std::min(length - aBufferOffset, aSource.Length());
+  bool isShared = false;
+  float* channelData = JS_GetFloat32ArrayData(channelArray, &isShared, nogc);
+  // The channelData arrays should all have originated in
+  // RestoreJSChannelData, where they are created unshared.
+  MOZ_ASSERT(!isShared);
+  PodMove(channelData + aBufferOffset, aSource.Data(), count);
+}
+
+void AudioBuffer::GetChannelData(JSContext* aJSContext, uint32_t aChannel,
+                                 JS::MutableHandle<JSObject*> aRetval,
+                                 ErrorResult& aRv) {
+  if (aChannel >= NumberOfChannels()) {
+    aRv.ThrowIndexSizeError(
+        nsPrintfCString("Channel number (%u) is out of range", aChannel));
+    return;
+  }
+
+  if (!RestoreJSChannelData(aJSContext)) {
+    aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
+    return;
+  }
+
+  aRetval.set(mJSChannels[aChannel]);
+}
+
+already_AddRefed<ThreadSharedFloatArrayBufferList>
+AudioBuffer::StealJSArrayDataIntoSharedChannels(JSContext* aJSContext) {
+  nsPIDOMWindowInner* global = GetParentObject();
+  if (!global || !global->AsGlobal()->HasJSGlobal()) {
+    return nullptr;
+  }
+
+  JSAutoRealm ar(aJSContext, global->AsGlobal()->GetGlobalJSObject());
+
+  // "1. If any of the AudioBuffer's ArrayBuffer have been detached, abort
+  // these steps, and return a zero-length channel data buffers to the
+  // invoker."
+  for (uint32_t i = 0; i < mJSChannels.Length(); ++i) {
+    JSObject* channelArray = mJSChannels[i];
+    if (!channelArray || Length() != JS_GetTypedArrayLength(channelArray)) {
+      // Either empty buffer or one of the arrays' buffers was detached.
+      return nullptr;
+    }
+  }
+
+  // "2. Detach all ArrayBuffers for arrays previously returned by
+  // getChannelData on this AudioBuffer."
+  // "3. Retain the underlying data buffers from those ArrayBuffers and return
+  // references to them to the invoker."
+  RefPtr<ThreadSharedFloatArrayBufferList> result =
+      new ThreadSharedFloatArrayBufferList(mJSChannels.Length());
+  for (uint32_t i = 0; i < mJSChannels.Length(); ++i) {
+    JS::Rooted<JSObject*> arrayBufferView(aJSContext, mJSChannels[i]);
+    bool isSharedMemory;
+    JS::Rooted<JSObject*> arrayBuffer(
+        aJSContext, JS_GetArrayBufferViewBuffer(aJSContext, arrayBufferView,
+                                                &isSharedMemory));
+    // The channel data arrays should all have originated in
+    // RestoreJSChannelData, where they are created unshared.
+    MOZ_ASSERT(!isSharedMemory);
+    auto stolenData = arrayBuffer
+                          ? static_cast<float*>(JS::StealArrayBufferContents(
+                                aJSContext, arrayBuffer))
+                          : nullptr;
+    if (stolenData) {
+      result->SetData(i, stolenData, js_free, stolenData);
+    } else {
+      NS_ASSERTION(i == 0, "some channels lost when contents not acquired");
+      return nullptr;
+    }
+  }
+
+  for (uint32_t i = 0; i < mJSChannels.Length(); ++i) {
+    mJSChannels[i] = nullptr;
+  }
+
+  return result.forget();
+}
+
+const AudioChunk& AudioBuffer::GetThreadSharedChannelsForRate(
+    JSContext* aJSContext) {
+  if (mSharedChannels.IsNull()) {
+    // mDuration is set in constructor
+    RefPtr<ThreadSharedFloatArrayBufferList> buffer =
+        StealJSArrayDataIntoSharedChannels(aJSContext);
+
+    if (buffer) {
+      SetSharedChannels(buffer.forget());
+    }
+  }
+
+  return mSharedChannels;
+}
+
+size_t AudioBuffer::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
+  size_t amount = aMallocSizeOf(this);
+  amount += mJSChannels.ShallowSizeOfExcludingThis(aMallocSizeOf);
+  amount += mSharedChannels.SizeOfExcludingThis(aMallocSizeOf, false);
+  return amount;
+}
+
+}  // namespace mozilla::dom