The Tor Browser: content/media/webaudio/AudioBuffer.h@97036ab72558

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

     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/. */

     7 #ifndef AudioBuffer_h_

     8 #define AudioBuffer_h_

    10 #include "nsWrapperCache.h"

    11 #include "nsCycleCollectionParticipant.h"

    12 #include "mozilla/Attributes.h"

    13 #include "nsAutoPtr.h"

    14 #include "nsTArray.h"

    15 #include "AudioContext.h"

    16 #include "js/TypeDecls.h"

    17 #include "mozilla/MemoryReporting.h"

    19 namespace mozilla {

    21 class ErrorResult;

    22 class ThreadSharedFloatArrayBufferList;

    24 namespace dom {

    26 class AudioContext;

    28 /**

    29  * An AudioBuffer keeps its data either in the mJSChannels objects, which

    30  * are Float32Arrays, or in mSharedChannels if the mJSChannels objects have

    31  * been neutered.

    32  */

    33 class AudioBuffer MOZ_FINAL : public nsWrapperCache

    34 {

    35 public:

    36   static already_AddRefed<AudioBuffer>

    37   Create(AudioContext* aContext, uint32_t aNumberOfChannels,

    38          uint32_t aLength, float aSampleRate,

    39          JSContext* aJSContext, ErrorResult& aRv);

    41   size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;

    43   NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(AudioBuffer)

    44   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(AudioBuffer)

    46   AudioContext* GetParentObject() const

    47   {

    48     return mContext;

    49   }

    51   virtual JSObject* WrapObject(JSContext* aCx) MOZ_OVERRIDE;

    53   float SampleRate() const

    54   {

    55     return mSampleRate;

    56   }

    58   int32_t Length() const

    59   {

    60     return mLength;

    61   }

    63   double Duration() const

    64   {

    65     return mLength / static_cast<double> (mSampleRate);

    66   }

    68   uint32_t NumberOfChannels() const

    69   {

    70     return mJSChannels.Length();

    71   }

    73   /**

    74    * If mSharedChannels is non-null, copies its contents to

    75    * new Float32Arrays in mJSChannels. Returns a Float32Array.

    76    */

    77   void GetChannelData(JSContext* aJSContext, uint32_t aChannel,

    78                       JS::MutableHandle<JSObject*> aRetval,

    79                       ErrorResult& aRv);

    81   void CopyFromChannel(const Float32Array& aDestination, uint32_t aChannelNumber,

    82                        uint32_t aStartInChannel, ErrorResult& aRv);

    83   void CopyToChannel(JSContext* aJSContext, const Float32Array& aSource,

    84                      uint32_t aChannelNumber, uint32_t aStartInChannel,

    85                      ErrorResult& aRv);

    87   /**

    88    * Returns a ThreadSharedFloatArrayBufferList containing the sample data.

    89    * Can return null if there is no data.

    90    */

    91   ThreadSharedFloatArrayBufferList* GetThreadSharedChannelsForRate(JSContext* aContext);

    93   // This replaces the contents of the JS array for the given channel.

    94   // This function needs to be called on an AudioBuffer which has not been

    95   // handed off to the content yet, and right after the object has been

    96   // initialized.

    97   void SetRawChannelContents(JSContext* aJSContext,

    98                              uint32_t aChannel,

    99                              float* aContents);

   101 protected:

   102   AudioBuffer(AudioContext* aContext, uint32_t aNumberOfChannels,

   103               uint32_t aLength, float aSampleRate);

   104   ~AudioBuffer();

   106   bool RestoreJSChannelData(JSContext* aJSContext);

   107   void ClearJSChannels();

   109   nsRefPtr<AudioContext> mContext;

   110   // Float32Arrays

   111   nsAutoTArray<JS::Heap<JSObject*>, 2> mJSChannels;

   113   // mSharedChannels aggregates the data from mJSChannels. This is non-null

   114   // if and only if the mJSChannels are neutered.

   115   nsRefPtr<ThreadSharedFloatArrayBufferList> mSharedChannels;

   117   uint32_t mLength;

   118   float mSampleRate;

   119 };

   121 }

   122 }

   124 #endif

The Tor Browser / file revision

content/media/webaudio/AudioBuffer.h@97036ab72558

content/media/webaudio/AudioBuffer.h