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/* -*- Mode: C++; tab-width: 2; 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 https://mozilla.org/MPL/2.0/. */
#ifndef DOM_MEDIA_CUBEBINPUTSTREAM_H_
#define DOM_MEDIA_CUBEBINPUTSTREAM_H_
#include "CubebUtils.h"
#include "mozilla/Maybe.h"
#include "mozilla/RefPtr.h"
#include "mozilla/UniquePtr.h"
#include "nsISupportsImpl.h"
namespace mozilla {
// A light-weight wrapper to operate the C style Cubeb APIs for an input-only
// audio stream in a C++-friendly way.
// Limitation: Do not call these APIs in an audio callback thread. Otherwise we
// may get a deadlock.
class CubebInputStream final {
public:
~CubebInputStream() = default;
class Listener {
public:
NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING;
// This will be fired on audio callback thread.
virtual long DataCallback(const void* aBuffer, long aFrames) = 0;
// This can be fired on any thread.
virtual void StateCallback(cubeb_state aState) = 0;
// This can be fired on any thread.
virtual void DeviceChangedCallback() = 0;
protected:
Listener() = default;
virtual ~Listener() = default;
};
// Return a non-null pointer if the stream has been initialized
// successfully. Otherwise return a null pointer.
static UniquePtr<CubebInputStream> Create(cubeb_devid aDeviceId,
uint32_t aChannels, uint32_t aRate,
bool aIsVoice, Listener* aListener);
// Start producing audio data.
int Start();
// Stop producing audio data.
int Stop();
// Gets the approximate stream latency in frames.
int Latency(uint32_t* aLatencyFrames);
private:
struct CubebDestroyPolicy {
void operator()(cubeb_stream* aStream) const;
};
CubebInputStream(already_AddRefed<Listener>&& aListener,
UniquePtr<cubeb_stream, CubebDestroyPolicy>&& aStream);
void Init();
template <typename Function, typename... Args>
int InvokeCubeb(Function aFunction, Args&&... aArgs);
// Static wrapper function cubeb callbacks.
static long DataCallback_s(cubeb_stream* aStream, void* aUser,
const void* aInputBuffer, void* aOutputBuffer,
long aFrames);
static void StateCallback_s(cubeb_stream* aStream, void* aUser,
cubeb_state aState);
static void DeviceChangedCallback_s(void* aUser);
// mListener must outlive the life time of the mStream.
const RefPtr<Listener> mListener;
// So must mCubeb (mStream has a bare pointer to cubeb).
const RefPtr<CubebUtils::CubebHandle> mCubeb;
const UniquePtr<cubeb_stream, CubebDestroyPolicy> mStream;
};
} // namespace mozilla
#endif // DOM_MEDIA_CUBEBINPUTSTREAM_H_
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