Don't crash if system has no audio device

Fixes: QTBUG-97838
Change-Id: I355958b99f62fc85228b3dd3afd06aa01005008c
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
(cherry picked from commit e95f7256fb534c3dd03b3091dd9835cd2f33d327)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

4 files changed, 59 insertions, 30 deletions

diff --git a/examples/multimedia/audiosource/audiosource.cpp b/examples/multimedia/audiosource/audiosource.cpp
index 1f84ae63a..ef0379e02 100644
--- a/examples/multimedia/audiosource/audiosource.cpp
+++ b/examples/multimedia/audiosource/audiosource.cpp
@@ -215,6 +215,9 @@ void InputTest::toggleMode()
     } else {
         m_modeButton->setText(tr("Enable pull mode"));
         auto *io = m_audioInput->start();
+        if (!io)
+            return;
+
         connect(io, &QIODevice::readyRead,
             [this, io]() {
                 static const qint64 BufferSize = 4096;
diff --git a/src/multimedia/audio/qaudiosink.cpp b/src/multimedia/audio/qaudiosink.cpp
index 6b16a71aa..c0cce2c79 100644
--- a/src/multimedia/audio/qaudiosink.cpp
+++ b/src/multimedia/audio/qaudiosink.cpp
@@ -123,9 +123,10 @@ QAudioSink::QAudioSink(const QAudioDevice &audioDevice, const QAudioFormat &form
     QObject(parent)
 {
     d = QPlatformMediaIntegration::instance()->devices()->audioOutputDevice(format, audioDevice);
-    if (d) {
+    if (d)
         connect(d, SIGNAL(stateChanged(QAudio::State)), SIGNAL(stateChanged(QAudio::State)));
-    }
+    else
+        qWarning() << ("No audio device detected");
 }
 
 /*!
@@ -144,7 +145,7 @@ QAudioSink::~QAudioSink()
 */
 QAudioFormat QAudioSink::format() const
 {
-    return d->format();
+    return d ? d->format() : QAudioFormat();
 }
 
 /*!
@@ -163,6 +164,8 @@ QAudioFormat QAudioSink::format() const
 */
 void QAudioSink::start(QIODevice* device)
 {
+    if (!d)
+        return;
     d->elapsedTime.restart();
     d->start(device);
 }
@@ -186,6 +189,8 @@ void QAudioSink::start(QIODevice* device)
 */
 QIODevice* QAudioSink::start()
 {
+    if (!d)
+        return nullptr;
     d->elapsedTime.restart();
     return d->start();
 }
@@ -198,7 +203,8 @@ QIODevice* QAudioSink::start()
 */
 void QAudioSink::stop()
 {
-    d->stop();
+    if (d)
+        d->stop();
 }
 
 /*!
@@ -207,7 +213,8 @@ void QAudioSink::stop()
 */
 void QAudioSink::reset()
 {
-    d->reset();
+    if (d)
+        d->reset();
 }
 
 /*!
@@ -218,7 +225,8 @@ void QAudioSink::reset()
 */
 void QAudioSink::suspend()
 {
-    d->suspend();
+    if (d)
+        d->suspend();
 }
 
 /*!
@@ -231,7 +239,8 @@ void QAudioSink::suspend()
 */
 void QAudioSink::resume()
 {
-     d->resume();
+    if (d)
+        d->resume();
 }
 
 /*!
@@ -242,7 +251,7 @@ void QAudioSink::resume()
 */
 qsizetype QAudioSink::bytesFree() const
 {
-    return d->bytesFree();
+    return d ? d->bytesFree() : 0;
 }
 
 /*!
@@ -255,7 +264,8 @@ qsizetype QAudioSink::bytesFree() const
 */
 void QAudioSink::setBufferSize(qsizetype value)
 {
-    d->setBufferSize(value);
+    if (d)
+        d->setBufferSize(value);
 }
 
 /*!
@@ -269,7 +279,7 @@ void QAudioSink::setBufferSize(qsizetype value)
 */
 qsizetype QAudioSink::bufferSize() const
 {
-    return d->bufferSize();
+    return d ? d->bufferSize() : 0;
 }
 
 /*!
@@ -278,7 +288,7 @@ qsizetype QAudioSink::bufferSize() const
 */
 qint64 QAudioSink::processedUSecs() const
 {
-    return d->processedUSecs();
+    return d ? d->processedUSecs() : 0;
 }
 
 /*!
@@ -287,7 +297,7 @@ qint64 QAudioSink::processedUSecs() const
 */
 qint64 QAudioSink::elapsedUSecs() const
 {
-    return d->state() == QAudio::StoppedState ? 0 : d->elapsedTime.nsecsElapsed()/1000;
+    return state() == QAudio::StoppedState ? 0 : d->elapsedTime.nsecsElapsed()/1000;
 }
 
 /*!
@@ -295,7 +305,7 @@ qint64 QAudioSink::elapsedUSecs() const
 */
 QAudio::Error QAudioSink::error() const
 {
-    return d->error();
+    return d ? d->error() : QAudio::OpenError;
 }
 
 /*!
@@ -303,7 +313,7 @@ QAudio::Error QAudioSink::error() const
 */
 QAudio::State QAudioSink::state() const
 {
-    return d->state();
+    return d ? d->state() : QAudio::StoppedState;
 }
 
 /*!
@@ -324,6 +334,8 @@ QAudio::State QAudioSink::state() const
 */
 void QAudioSink::setVolume(qreal volume)
 {
+    if (!d)
+        return;
     qreal v = qBound(qreal(0.0), volume, qreal(1.0));
     d->setVolume(v);
 }
@@ -333,7 +345,7 @@ void QAudioSink::setVolume(qreal volume)
 */
 qreal QAudioSink::volume() const
 {
-    return d->volume();
+    return d ? d->volume() : 1.0;
 }
 
 /*!
diff --git a/src/multimedia/audio/qaudiosource.cpp b/src/multimedia/audio/qaudiosource.cpp
index a5f6de89d..4c2fb50b3 100644
--- a/src/multimedia/audio/qaudiosource.cpp
+++ b/src/multimedia/audio/qaudiosource.cpp
@@ -135,6 +135,9 @@ QAudioSource::QAudioSource(const QAudioDevice &audioDevice, const QAudioFormat &
     d = QPlatformMediaIntegration::instance()->devices()->audioInputDevice(format, audioDevice);
     if (d)
         connect(d, SIGNAL(stateChanged(QAudio::State)), SIGNAL(stateChanged(QAudio::State)));
+    else
+        qWarning() << ("No audio device detected");
+
 }
 
 /*!
@@ -163,6 +166,8 @@ QAudioSource::~QAudioSource()
 
 void QAudioSource::start(QIODevice* device)
 {
+    if (!d)
+        return;
     d->elapsedTime.start();
     d->start(device);
 }
@@ -187,6 +192,8 @@ void QAudioSource::start(QIODevice* device)
 
 QIODevice* QAudioSource::start()
 {
+    if (!d)
+        return nullptr;
     d->elapsedTime.start();
     return d->start();
 }
@@ -197,7 +204,7 @@ QIODevice* QAudioSource::start()
 
 QAudioFormat QAudioSource::format() const
 {
-    return d->format();
+    return d ? d->format() : QAudioFormat();
 }
 
 /*!
@@ -209,7 +216,8 @@ QAudioFormat QAudioSource::format() const
 
 void QAudioSource::stop()
 {
-    d->stop();
+    if (d)
+        d->stop();
 }
 
 /*!
@@ -218,7 +226,8 @@ void QAudioSource::stop()
 
 void QAudioSource::reset()
 {
-    d->reset();
+    if (d)
+        d->reset();
 }
 
 /*!
@@ -230,7 +239,8 @@ void QAudioSource::reset()
 
 void QAudioSource::suspend()
 {
-    d->suspend();
+    if (d)
+        d->suspend();
 }
 
 /*!
@@ -244,7 +254,8 @@ void QAudioSource::suspend()
 
 void QAudioSource::resume()
 {
-     d->resume();
+    if (d)
+        d->resume();
 }
 
 /*!
@@ -259,7 +270,8 @@ void QAudioSource::resume()
 
 void QAudioSource::setBufferSize(qsizetype value)
 {
-    d->setBufferSize(value);
+    if (d)
+        d->setBufferSize(value);
 }
 
 /*!
@@ -274,7 +286,7 @@ void QAudioSource::setBufferSize(qsizetype value)
 
 qsizetype QAudioSource::bufferSize() const
 {
-    return d->bufferSize();
+    return d ? d->bufferSize() : 0;
 }
 
 /*!
@@ -290,7 +302,7 @@ qsizetype QAudioSource::bytesAvailable() const
     -If not ActiveState|IdleState, return 0
     -return amount of audio data available to read
     */
-    return d->bytesReady();
+    return d ? d->bytesReady() : 0;
 }
 
 /*!
@@ -309,6 +321,8 @@ qsizetype QAudioSource::bytesAvailable() const
 */
 void QAudioSource::setVolume(qreal volume)
 {
+    if (!d)
+        return;
     qreal v = qBound(qreal(0.0), volume, qreal(1.0));
     d->setVolume(v);
 }
@@ -321,7 +335,7 @@ void QAudioSource::setVolume(qreal volume)
 */
 qreal QAudioSource::volume() const
 {
-    return d->volume();
+    return d ? d->volume() : 1.0;
 }
 
 /*!
@@ -331,7 +345,7 @@ qreal QAudioSource::volume() const
 
 qint64 QAudioSource::processedUSecs() const
 {
-    return d->processedUSecs();
+    return d ? d->processedUSecs() : 0;
 }
 
 /*!
@@ -343,7 +357,7 @@ qint64 QAudioSource::processedUSecs() const
 
 qint64 QAudioSource::elapsedUSecs() const
 {
-    return d->state() == QAudio::StoppedState ? 0 : d->elapsedTime.nsecsElapsed()/1000;
+    return state() == QAudio::StoppedState ? 0 : d->elapsedTime.nsecsElapsed()/1000;
 }
 
 /*!
@@ -352,7 +366,7 @@ qint64 QAudioSource::elapsedUSecs() const
 
 QAudio::Error QAudioSource::error() const
 {
-    return d->error();
+    return d ? d->error() : QAudio::OpenError;
 }
 
 /*!
@@ -361,7 +375,7 @@ QAudio::Error QAudioSource::error() const
 
 QAudio::State QAudioSource::state() const
 {
-    return d->state();
+    return d ? d->state() : QAudio::StoppedState;
 }
 
 /*!
diff --git a/src/multimedia/platform/qplatformmediadevices.cpp b/src/multimedia/platform/qplatformmediadevices.cpp
index 4ac1ec14c..fcedfe6ac 100644
--- a/src/multimedia/platform/qplatformmediadevices.cpp
+++ b/src/multimedia/platform/qplatformmediadevices.cpp
@@ -85,7 +85,7 @@ QPlatformAudioSource* QPlatformMediaDevices::audioInputDevice(const QAudioFormat
     if (info.isNull())
         info = audioInputs().value(0);
 
-    QPlatformAudioSource* p = createAudioSource(info);
+    QPlatformAudioSource* p = !info.isNull() ? createAudioSource(info) : nullptr;
     if (p)
         p->setFormat(format);
     return p;
@@ -97,7 +97,7 @@ QPlatformAudioSink* QPlatformMediaDevices::audioOutputDevice(const QAudioFormat
     if (info.isNull())
         info = audioOutputs().value(0);
 
-    QPlatformAudioSink* p = createAudioSink(info);
+    QPlatformAudioSink* p = !info.isNull() ? createAudioSink(info) : nullptr;
     if (p)
         p->setFormat(format);
     return p;