services/pipewire: add reconnect support

changelog/next.md

@@ -18,6 +18,7 @@ set shell id.
 - Added the ability to override Quickshell.cacheDir with a custom path.
 - Added minimized, maximized, and fullscreen properties to FloatingWindow.
 - Added the ability to handle move and resize events to FloatingWindow.
+- Pipewire service now reconnects if pipewire dies or a protocol error occurs.
 
 ## Other Changes
 

src/services/pipewire/connection.cpp

@@ -1,13 +1,135 @@
 #include "connection.hpp"
 
+#include <qdir.h>
+#include <qfilesystemwatcher.h>
+#include <qlogging.h>
+#include <qloggingcategory.h>
+#include <qnamespace.h>
 #include <qobject.h>
+#include <qtenvironmentvariables.h>
+#include <unistd.h>
+
+#include "../../core/logcat.hpp"
+#include "core.hpp"
 
 namespace qs::service::pipewire {
 
-PwConnection::PwConnection(QObject* parent): QObject(parent) {
-	if (this->core.isValid()) {
-		this->registry.init(this->core);
+namespace {
+QS_LOGGING_CATEGORY(logConnection, "quickshell.service.pipewire.connection", QtWarningMsg);
 }
+
+PwConnection::PwConnection(QObject* parent): QObject(parent) {
+	this->runtimeDir = PwConnection::resolveRuntimeDir();
+
+	QObject::connect(&this->core, &PwCore::fatalError, this, &PwConnection::queueFatalError);
+
+	if (!this->tryConnect(false)
+	    && qEnvironmentVariableIntValue("QS_PIPEWIRE_IMMEDIATE_RECONNECT") == 1)
+	{
+		this->beginReconnect();
+	}
+}
+
+QString PwConnection::resolveRuntimeDir() {
+	auto runtimeDir = qEnvironmentVariable("PIPEWIRE_RUNTIME_DIR");
+	if (runtimeDir.isEmpty()) {
+		runtimeDir = qEnvironmentVariable("XDG_RUNTIME_DIR");
+	}
+
+	if (runtimeDir.isEmpty()) {
+		runtimeDir = QString("/run/user/%1").arg(getuid());
+	}
+
+	return runtimeDir;
+}
+
+void PwConnection::beginReconnect() {
+	if (this->core.isValid()) {
+		this->stopSocketWatcher();
+		return;
+	}
+
+	if (!qEnvironmentVariableIsEmpty("PIPEWIRE_REMOTE")) return;
+
+	if (this->runtimeDir.isEmpty()) {
+		qCWarning(
+		    logConnection
+		) << "Cannot watch runtime dir for pipewire reconnects: runtime dir is empty.";
+		return;
+	}
+
+	this->startSocketWatcher();
+	this->tryConnect(true);
+}
+
+bool PwConnection::tryConnect(bool retry) {
+	if (this->core.isValid()) return true;
+
+	qCDebug(logConnection) << "Attempting reconnect...";
+	if (!this->core.start(retry)) {
+		return false;
+	}
+
+	qCInfo(logConnection) << "Connection established";
+	this->stopSocketWatcher();
+
+	this->registry.init(this->core);
+	return true;
+}
+
+void PwConnection::startSocketWatcher() {
+	if (this->socketWatcher != nullptr) return;
+	if (!qEnvironmentVariableIsEmpty("PIPEWIRE_REMOTE")) return;
+
+	auto dir = QDir(this->runtimeDir);
+	if (!dir.exists()) {
+		qCWarning(logConnection) << "Cannot wait for a new pipewire socket, runtime dir does not exist:"
+		                         << this->runtimeDir;
+		return;
+	}
+
+	this->socketWatcher = new QFileSystemWatcher(this);
+	this->socketWatcher->addPath(this->runtimeDir);
+
+	QObject::connect(
+	    this->socketWatcher,
+	    &QFileSystemWatcher::directoryChanged,
+	    this,
+	    &PwConnection::onRuntimeDirChanged
+	);
+}
+
+void PwConnection::stopSocketWatcher() {
+	if (this->socketWatcher == nullptr) return;
+
+	this->socketWatcher->deleteLater();
+	this->socketWatcher = nullptr;
+}
+
+void PwConnection::queueFatalError() {
+	if (this->fatalErrorQueued) return;
+
+	this->fatalErrorQueued = true;
+	QMetaObject::invokeMethod(this, &PwConnection::onFatalError, Qt::QueuedConnection);
+}
+
+void PwConnection::onFatalError() {
+	this->fatalErrorQueued = false;
+
+	this->defaults.reset();
+	this->registry.reset();
+	this->core.shutdown();
+
+	this->beginReconnect();
+}
+
+void PwConnection::onRuntimeDirChanged(const QString& /*path*/) {
+	if (this->core.isValid()) {
+		this->stopSocketWatcher();
+		return;
+	}
+
+	this->tryConnect(true);
 }
 
 PwConnection* PwConnection::instance() {

src/services/pipewire/connection.hpp

@@ -1,9 +1,13 @@
 #pragma once
 
+#include <qstring.h>
+
 #include "core.hpp"
 #include "defaults.hpp"
 #include "registry.hpp"
 
+class QFileSystemWatcher;
+
 namespace qs::service::pipewire {
 
 class PwConnection: public QObject {
@@ -18,6 +22,23 @@ public:
 	static PwConnection* instance();
 
 private:
+	static QString resolveRuntimeDir();
+
+	void beginReconnect();
+	bool tryConnect(bool retry);
+	void startSocketWatcher();
+	void stopSocketWatcher();
+
+private slots:
+	void queueFatalError();
+	void onFatalError();
+	void onRuntimeDirChanged(const QString& path);
+
+private:
+	QString runtimeDir;
+	QFileSystemWatcher* socketWatcher = nullptr;
+	bool fatalErrorQueued = false;
+
 	// init/destroy order is important. do not rearrange.
 	PwCore core;
 };

src/services/pipewire/core.cpp

@@ -27,7 +27,7 @@ const pw_core_events PwCore::EVENTS = {
     .info = nullptr,
     .done = &PwCore::onSync,
     .ping = nullptr,
-    .error = nullptr,
+    .error = &PwCore::onError,
     .remove_id = nullptr,
     .bound_id = nullptr,
     .add_mem = nullptr,
@@ -36,26 +36,46 @@ const pw_core_events PwCore::EVENTS = {
 };
 
 PwCore::PwCore(QObject* parent): QObject(parent), notifier(QSocketNotifier::Read) {
-	qCInfo(logLoop) << "Creating pipewire event loop.";
 	pw_init(nullptr, nullptr);
+}
+
+bool PwCore::start(bool retry) {
+	if (this->core != nullptr) return true;
+
+	qCInfo(logLoop) << "Creating pipewire event loop.";
 
 	this->loop = pw_loop_new(nullptr);
 	if (this->loop == nullptr) {
+		if (retry) {
+			qCInfo(logLoop) << "Failed to create pipewire event loop.";
+		} else {
 			qCCritical(logLoop) << "Failed to create pipewire event loop.";
-		return;
+		}
+		this->shutdown();
+		return false;
 	}
 
 	this->context = pw_context_new(this->loop, nullptr, 0);
 	if (this->context == nullptr) {
+		if (retry) {
+			qCInfo(logLoop) << "Failed to create pipewire context.";
+		} else {
 			qCCritical(logLoop) << "Failed to create pipewire context.";
-		return;
+		}
+		this->shutdown();
+		return false;
 	}
 
 	qCInfo(logLoop) << "Connecting to pipewire server.";
 	this->core = pw_context_connect(this->context, nullptr, 0);
 	if (this->core == nullptr) {
+		if (retry) {
+			qCInfo(logLoop) << "Failed to connect pipewire context. Errno:" << errno;
+		} else {
 			qCCritical(logLoop) << "Failed to connect pipewire context. Errno:" << errno;
-		return;
+		}
+		this->shutdown();
+		return false;
 	}
 
 	pw_core_add_listener(this->core, &this->listener.hook, &PwCore::EVENTS, this);
@@ -66,22 +86,34 @@ PwCore::PwCore(QObject* parent): QObject(parent), notifier(QSocketNotifier::Read
 	this->notifier.setSocket(fd);
 	QObject::connect(&this->notifier, &QSocketNotifier::activated, this, &PwCore::poll);
 	this->notifier.setEnabled(true);
+
+	return true;
+}
+
+void PwCore::shutdown() {
+	if (this->core != nullptr) {
+		this->listener.remove();
+		pw_core_disconnect(this->core);
+		this->core = nullptr;
+	}
+
+	if (this->context != nullptr) {
+		pw_context_destroy(this->context);
+		this->context = nullptr;
+	}
+
+	if (this->loop != nullptr) {
+		pw_loop_destroy(this->loop);
+		this->loop = nullptr;
+	}
+
+	this->notifier.setEnabled(false);
+	QObject::disconnect(&this->notifier, nullptr, this, nullptr);
 }
 
 PwCore::~PwCore() {
 	qCInfo(logLoop) << "Destroying PwCore.";
-
-	if (this->loop != nullptr) {
-		if (this->context != nullptr) {
-			if (this->core != nullptr) {
-				pw_core_disconnect(this->core);
-			}
-
-			pw_context_destroy(this->context);
-		}
-
-		pw_loop_destroy(this->loop);
-	}
+	this->shutdown();
 }
 
 bool PwCore::isValid() const {
@@ -90,6 +122,7 @@ bool PwCore::isValid() const {
 }
 
 void PwCore::poll() {
+	if (this->loop == nullptr) return;
 	qCDebug(logLoop) << "Pipewire event loop received new events, iterating.";
 	// Spin pw event loop.
 	pw_loop_iterate(this->loop, 0);
@@ -107,6 +140,18 @@ void PwCore::onSync(void* data, quint32 id, qint32 seq) {
 	emit self->synced(id, seq);
 }
 
+void PwCore::onError(void* data, quint32 id, qint32 /*seq*/, qint32 res, const char* message) {
+	auto* self = static_cast<PwCore*>(data);
+
+	if (message != nullptr) {
+		qCWarning(logLoop) << "Fatal pipewire error on object" << id << "with code" << res << message;
+	} else {
+		qCWarning(logLoop) << "Fatal pipewire error on object" << id << "with code" << res;
+	}
+
+	emit self->fatalError();
+}
+
 SpaHook::SpaHook() { // NOLINT
 	spa_zero(this->hook);
 }

src/services/pipewire/core.hpp

@@ -30,6 +30,9 @@ public:
 	~PwCore() override;
 	Q_DISABLE_COPY_MOVE(PwCore);
 
+	bool start(bool retry);
+	void shutdown();
+
 	[[nodiscard]] bool isValid() const;
 	[[nodiscard]] qint32 sync(quint32 id) const;
 
@@ -40,6 +43,7 @@ public:
 signals:
 	void polled();
 	void synced(quint32 id, qint32 seq);
+	void fatalError();
 
 private slots:
 	void poll();
@@ -48,6 +52,7 @@ private:
 	static const pw_core_events EVENTS;
 
 	static void onSync(void* data, quint32 id, qint32 seq);
+	static void onError(void* data, quint32 id, qint32 seq, qint32 res, const char* message);
 
 	QSocketNotifier notifier;
 	SpaHook listener;

src/services/pipewire/defaults.cpp

@@ -31,6 +31,22 @@ PwDefaultTracker::PwDefaultTracker(PwRegistry* registry): registry(registry) {
 	QObject::connect(registry, &PwRegistry::nodeAdded, this, &PwDefaultTracker::onNodeAdded);
 }
 
+void PwDefaultTracker::reset() {
+	if (auto* meta = this->defaultsMetadata.object()) {
+		QObject::disconnect(meta, nullptr, this, nullptr);
+	}
+
+	this->defaultsMetadata.setObject(nullptr);
+	this->setDefaultSink(nullptr);
+	this->setDefaultSinkName(QString());
+	this->setDefaultSource(nullptr);
+	this->setDefaultSourceName(QString());
+	this->setDefaultConfiguredSink(nullptr);
+	this->setDefaultConfiguredSinkName(QString());
+	this->setDefaultConfiguredSource(nullptr);
+	this->setDefaultConfiguredSourceName(QString());
+}
+
 void PwDefaultTracker::onMetadataAdded(PwMetadata* metadata) {
 	if (metadata->name() == "default") {
 		qCDebug(logDefaults) << "Got new defaults metadata object" << metadata;

src/services/pipewire/defaults.hpp

@@ -12,6 +12,7 @@ class PwDefaultTracker: public QObject {
 
 public:
 	explicit PwDefaultTracker(PwRegistry* registry);
+	void reset();
 
 	[[nodiscard]] PwNode* defaultSink() const;
 	[[nodiscard]] PwNode* defaultSource() const;

src/services/pipewire/qml.cpp

@@ -2,7 +2,6 @@
 
 #include <qcontainerfwd.h>
 #include <qlist.h>
-#include <qnamespace.h>
 #include <qobject.h>
 #include <qqmllist.h>
 #include <qtmetamacros.h>
@@ -99,15 +98,8 @@ Pipewire::Pipewire(QObject* parent): QObject(parent) {
 	    &Pipewire::defaultConfiguredAudioSourceChanged
 	);
 
-	if (!connection->registry.isInitialized()) {
-		QObject::connect(
-		    &connection->registry,
-		    &PwRegistry::initialized,
-		    this,
-		    &Pipewire::readyChanged,
-		    Qt::SingleShotConnection
-		);
-	}
+	QObject::connect(&connection->registry, &PwRegistry::initialized, this, &Pipewire::readyChanged);
+	QObject::connect(&connection->registry, &PwRegistry::cleared, this, &Pipewire::readyChanged);
 }
 
 ObjectModel<PwNodeIface>* Pipewire::nodes() { return &this->mNodes; }

src/services/pipewire/registry.cpp

@@ -134,6 +134,46 @@ void PwRegistry::init(PwCore& core) {
 	this->coreSyncSeq = this->core->sync(PW_ID_CORE);
 }
 
+void PwRegistry::reset() {
+	if (this->core != nullptr) {
+		QObject::disconnect(this->core, nullptr, this, nullptr);
+	}
+
+	this->listener.remove();
+
+	if (this->object != nullptr) {
+		pw_proxy_destroy(reinterpret_cast<pw_proxy*>(this->object));
+		this->object = nullptr;
+	}
+
+	for (auto* meta: this->metadata.values()) {
+		meta->safeDestroy();
+	}
+	this->metadata.clear();
+
+	for (auto* link: this->links.values()) {
+		link->safeDestroy();
+	}
+	this->links.clear();
+
+	for (auto* node: this->nodes.values()) {
+		node->safeDestroy();
+	}
+	this->nodes.clear();
+
+	for (auto* device: this->devices.values()) {
+		device->safeDestroy();
+	}
+	this->devices.clear();
+
+	this->linkGroups.clear();
+	this->initState = InitState::SendingObjects;
+	this->coreSyncSeq = 0;
+	this->core = nullptr;
+
+	emit this->cleared();
+}
+
 void PwRegistry::onCoreSync(quint32 id, qint32 seq) {
 	if (id != PW_ID_CORE || seq != this->coreSyncSeq) return;
 

src/services/pipewire/registry.hpp

@@ -116,6 +116,7 @@ class PwRegistry
 
 public:
 	void init(PwCore& core);
+	void reset();
 
 	[[nodiscard]] bool isInitialized() const { return this->initState == InitState::Done; }
 
@@ -136,6 +137,7 @@ signals:
 	void linkGroupAdded(PwLinkGroup* group);
 	void metadataAdded(PwMetadata* metadata);
 	void initialized();
+	void cleared();
 
 private slots:
 	void onLinkGroupDestroyed(QObject* object);