service/pipewire: add pipewire module

src/services/pipewire/metadata.cpp

@@ -0,0 +1,146 @@
+#include "metadata.hpp"
+#include <array>
+#include <cstring>
+
+#include <pipewire/extensions/metadata.h>
+#include <qlogging.h>
+#include <qloggingcategory.h>
+#include <qobject.h>
+#include <qtmetamacros.h>
+#include <qtypes.h>
+#include <spa/utils/json.h>
+
+#include "registry.hpp"
+
+namespace qs::service::pipewire {
+
+Q_LOGGING_CATEGORY(logMeta, "quickshell.service.pipewire.metadata", QtWarningMsg);
+
+void PwMetadata::bindHooks() {
+	pw_metadata_add_listener(this->proxy(), &this->listener.hook, &PwMetadata::EVENTS, this);
+}
+
+void PwMetadata::unbindHooks() { this->listener.remove(); }
+
+const pw_metadata_events PwMetadata::EVENTS = {
+    .version = PW_VERSION_METADATA_EVENTS,
+    .property = &PwMetadata::onProperty,
+};
+
+int PwMetadata::onProperty(
+    void* data,
+    quint32 subject,
+    const char* key,
+    const char* type,
+    const char* value
+) {
+	auto* self = static_cast<PwMetadata*>(data);
+	qCDebug(logMeta) << "Received metadata for" << self << "- subject:" << subject
+	                 << "key:" << QString(key) << "type:" << QString(type)
+	                 << "value:" << QString(value);
+
+	emit self->registry->metadataUpdate(self, subject, key, type, value);
+
+	// ideally we'd dealloc metadata that wasn't picked up but there's no information
+	// available about if updates can come in later, so I assume they can.
+
+	return 0; // ??? - no docs and no reason for a callback to return an int
+}
+
+PwDefaultsMetadata::PwDefaultsMetadata(PwRegistry* registry) {
+	QObject::connect(
+	    registry,
+	    &PwRegistry::metadataUpdate,
+	    this,
+	    &PwDefaultsMetadata::onMetadataUpdate
+	);
+}
+
+QString PwDefaultsMetadata::defaultSink() const { return this->mDefaultSink; }
+
+QString PwDefaultsMetadata::defaultSource() const { return this->mDefaultSource; }
+
+// we don't really care if the metadata objects are destroyed, but try to ref them so we get property updates
+void PwDefaultsMetadata::onMetadataUpdate(
+    PwMetadata* metadata,
+    quint32 subject,
+    const char* key,
+    const char* /*type*/,
+    const char* value
+) {
+	if (subject != 0) return;
+
+	// non "configured" sinks and sources have lower priority as wireplumber seems to only change
+	// the "configured" ones.
+
+	bool sink = false;
+	if (strcmp(key, "default.configured.audio.sink") == 0) {
+		sink = true;
+		this->sinkConfigured = true;
+	} else if ((!this->sinkConfigured && strcmp(key, "default.audio.sink") == 0)) {
+		sink = true;
+	}
+
+	if (sink) {
+		this->defaultSinkHolder.setObject(metadata);
+
+		auto newSink = PwDefaultsMetadata::parseNameSpaJson(value);
+		qCInfo(logMeta) << "Got default sink" << newSink << "configured:" << this->sinkConfigured;
+		if (newSink == this->mDefaultSink) return;
+
+		this->mDefaultSink = newSink;
+		emit this->defaultSinkChanged();
+		return;
+	}
+
+	bool source = false;
+	if (strcmp(key, "default.configured.audio.source") == 0) {
+		source = true;
+		this->sourceConfigured = true;
+	} else if ((!this->sourceConfigured && strcmp(key, "default.audio.source") == 0)) {
+		source = true;
+	}
+
+	if (source) {
+		this->defaultSourceHolder.setObject(metadata);
+
+		auto newSource = PwDefaultsMetadata::parseNameSpaJson(value);
+		qCInfo(logMeta) << "Got default source" << newSource << "configured:" << this->sourceConfigured;
+		if (newSource == this->mDefaultSource) return;
+
+		this->mDefaultSource = newSource;
+		emit this->defaultSourceChanged();
+		return;
+	}
+}
+
+QString PwDefaultsMetadata::parseNameSpaJson(const char* spaJson) {
+	auto iter = std::array<spa_json, 2>();
+	spa_json_init(&iter[0], spaJson, strlen(spaJson));
+
+	if (spa_json_enter_object(&iter[0], &iter[1]) < 0) {
+		qCWarning(logMeta) << "Failed to parse source/sink SPA json - failed to enter object of"
+		                   << QString(spaJson);
+		return "";
+	}
+
+	auto buf = std::array<char, 512>();
+	while (spa_json_get_string(&iter[1], buf.data(), buf.size()) > 0) {
+		if (strcmp(buf.data(), "name") != 0) continue;
+
+		if (spa_json_get_string(&iter[1], buf.data(), buf.size()) < 0) {
+			qCWarning(logMeta
+			) << "Failed to parse source/sink SPA json - failed to read value of name property"
+			  << QString(spaJson);
+			return "";
+		}
+
+		return QString(buf.data());
+	}
+
+	qCWarning(logMeta) << "Failed to parse source/sink SPA json - failed to find name property of"
+	                   << QString(spaJson);
+	return "";
+}
+
+} // namespace qs::service::pipewire