1// Copyright (C) 2016 The Qt Company Ltd.
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4#ifndef QAUDIOOUTPUTPULSE_H
5#define QAUDIOOUTPUTPULSE_H
6
7//
8// W A R N I N G
9// -------------
10//
11// This file is not part of the Qt API. It exists purely as an
12// implementation detail. This header file may change from version to
13// version without notice, or even be removed.
14//
15// We mean it.
16//
17
18#include <QtCore/qfile.h>
19#include <QtCore/qtimer.h>
20#include <QtCore/qstring.h>
21#include <QtCore/qstringlist.h>
22#include <QtCore/qelapsedtimer.h>
23#include <QtCore/qiodevice.h>
24
25#include "qaudio.h"
26#include "qaudiodevice.h"
27#include "pulseaudio/qpulsehelpers_p.h"
28
29#include <private/qaudiosystem_p.h>
30#include <private/qaudiostatemachine_p.h>
31#include <pulse/pulseaudio.h>
32
33QT_BEGIN_NAMESPACE
34
35class QPulseAudioSink : public QPlatformAudioSink
36{
37 friend class PulseOutputPrivate;
38 Q_OBJECT
39
40public:
41 QPulseAudioSink(const QByteArray &device, QObject *parent);
42 ~QPulseAudioSink() override;
43
44 void start(QIODevice *device) override;
45 QIODevice *start() override;
46 void stop() override;
47 void reset() override;
48 void suspend() override;
49 void resume() override;
50 qsizetype bytesFree() const override;
51 void setBufferSize(qsizetype value) override;
52 qsizetype bufferSize() const override;
53 qint64 processedUSecs() const override;
54 QAudio::Error error() const override;
55 QAudio::State state() const override;
56 void setFormat(const QAudioFormat &format);
57 QAudioFormat format() const override;
58
59 void setVolume(qreal volume) override;
60 qreal volume() const override;
61
62 void streamUnderflowCallback();
63 void streamDrainedCallback();
64
65protected:
66 void timerEvent(QTimerEvent *event) override;
67
68private:
69 void startPulling();
70 void stopTimer();
71
72 bool open();
73 void close();
74 qint64 write(const char *data, qint64 len);
75
76private Q_SLOTS:
77 void userFeed();
78 void onPulseContextFailed();
79
80private:
81 using PAOperationHandle = QPulseAudioInternal::PAOperationHandle;
82 using PAStreamHandle = QPulseAudioInternal::PAStreamHandle;
83 PAOperationHandle exchangeDrainOperation(pa_operation *newOperation);
84
85 qsizetype defaultBufferSize() const;
86
87 pa_sample_spec m_spec = {};
88 // calculate timing manually, as pulseaudio doesn't give us good enough data
89 mutable timeval lastTimingInfo = {};
90
91 mutable QList<qint64> latencyList; // last latency values
92
93 QByteArray m_device;
94 QByteArray m_streamName;
95 QAudioFormat m_format;
96 QBasicTimer m_tickTimer;
97
98 QIODevice *m_audioSource = nullptr;
99 PAStreamHandle m_stream;
100 std::vector<char> m_audioBuffer;
101
102 qint64 m_totalTimeValue = 0;
103 qint64 m_elapsedTimeOffset = 0;
104 mutable qint64 averageLatency = 0; // average latency
105 mutable qint64 lastProcessedUSecs = 0;
106 qreal m_volume = 1.0;
107
108 std::atomic<pa_operation *> m_drainOperation = nullptr;
109 qsizetype m_bufferSize = 0;
110 std::optional<qsizetype> m_userBufferSize = std::nullopt;
111 int m_pullingPeriodSize = 0;
112 int m_pullingPeriodTime = 0;
113 bool m_pullMode = true;
114 bool m_opened = false;
115
116 QAudioStateMachine m_stateMachine;
117};
118
119class PulseOutputPrivate : public QIODevice
120{
121 friend class QPulseAudioSink;
122 Q_OBJECT
123
124public:
125 PulseOutputPrivate(QPulseAudioSink *audio);
126 ~PulseOutputPrivate() override = default;
127
128protected:
129 qint64 readData(char *data, qint64 len) override;
130 qint64 writeData(const char *data, qint64 len) override;
131
132private:
133 QPulseAudioSink *m_audioDevice;
134};
135
136QT_END_NAMESPACE
137
138#endif
139

source code of qtmultimedia/src/multimedia/pulseaudio/qpulseaudiosink_p.h