Add property watches
Property watches cache DBus property values given an externally
supplied index of property names and paths, in an externally
supplied storage location.
Change-Id: I155081da88c3ab0e4f6a13b012fc9719203b1888
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/src/propertywatch.hpp b/src/propertywatch.hpp
new file mode 100644
index 0000000..59db599
--- /dev/null
+++ b/src/propertywatch.hpp
@@ -0,0 +1,167 @@
+/**
+ * @file propertywatch.hpp
+ * @brief PropertyWatch class declarations.
+ *
+ * In general class users should include propertywatchimpl.hpp instead to avoid
+ * link failures.
+ */
+#pragma once
+
+#include "data_types.hpp"
+#include "watch.hpp"
+
+namespace phosphor
+{
+namespace dbus
+{
+namespace monitoring
+{
+
+/** @class PropertyWatch
+ * @brief Type agnostic, factored out logic for property watches.
+ *
+ * A property watch maintains the state of one or more DBus properties
+ * as specified by the supplied index.
+ */
+template <typename DBusInterfaceType>
+class PropertyWatch : public Watch
+{
+ public:
+ PropertyWatch() = delete;
+ PropertyWatch(const PropertyWatch&) = delete;
+ PropertyWatch(PropertyWatch&&) = default;
+ PropertyWatch& operator=(const PropertyWatch&) = delete;
+ PropertyWatch& operator=(PropertyWatch&&) = default;
+ virtual ~PropertyWatch() = default;
+ explicit PropertyWatch(const PropertyIndex& watchIndex)
+ : Watch(), index(watchIndex), alreadyRan(false) {}
+
+ /** @brief Start the watch.
+ *
+ * Watch start interface implementation for PropertyWatch.
+ */
+ void start() override;
+
+ /** @brief Update properties.
+ *
+ * Subclasses to query the properties specified by the index
+ * and update the cache.
+ *
+ * @param[in] busName - The busname hosting the interface to query.
+ * @param[in] path - The path of the interface to query.
+ * @param[in] interface - The interface to query.
+ */
+ virtual void updateProperties(
+ const std::string& busName,
+ const std::string& path,
+ const std::string& interface) = 0;
+
+ /** @brief Dbus signal callback for PropertiesChanged.
+ *
+ * Subclasses to update the cache.
+ *
+ * @param[in] message - The org.freedesktop.DBus.PropertiesChanged
+ * message.
+ * @param[in] path - The path associated with the message.
+ * @param[in] interface - The interface associated with the message.
+ */
+ virtual void propertiesChanged(
+ sdbusplus::message::message&,
+ const std::string& path,
+ const std::string& interface) = 0;
+
+ /** @brief Dbus signal callback for InterfacesAdded.
+ *
+ * Subclasses to update the cache.
+ *
+ * @param[in] msg - The org.freedesktop.DBus.PropertiesChanged
+ * message.
+ */
+ virtual void interfacesAdded(sdbusplus::message::message& msg) = 0;
+
+ protected:
+
+ /** @brief Property names and their associated storage. */
+ const PropertyIndex& index;
+
+ private:
+
+ /** @brief The start method should only be invoked once. */
+ bool alreadyRan;
+};
+
+/** @class PropertyWatchOfType
+ * @brief Type specific logic for PropertyWatch.
+ *
+ * @tparam DBusInterfaceType - DBus access delegate.
+ * @tparam T - The type of the properties being watched.
+ */
+template <typename T, typename DBusInterfaceType>
+class PropertyWatchOfType : public PropertyWatch<DBusInterfaceType>
+{
+ public:
+ PropertyWatchOfType() = default;
+ PropertyWatchOfType(const PropertyWatchOfType&) = delete;
+ PropertyWatchOfType(PropertyWatchOfType&&) = default;
+ PropertyWatchOfType& operator=(const PropertyWatchOfType&) = delete;
+ PropertyWatchOfType& operator=(PropertyWatchOfType&&) = default;
+ ~PropertyWatchOfType() = default;
+ explicit PropertyWatchOfType(
+ const PropertyIndex& watchIndex) :
+ PropertyWatch<DBusInterfaceType>(watchIndex) {}
+
+ /** @brief PropertyMatch implementation for PropertyWatchOfType.
+ *
+ * @param[in] busName - The busname hosting the interface to query.
+ * @param[in] path - The path of the interface to query.
+ * @param[in] interface - The interface to query.
+ */
+ void updateProperties(
+ const std::string& busName,
+ const std::string& path,
+ const std::string& interface) override;
+
+ /** @brief PropertyMatch implementation for PropertyWatchOfType.
+ *
+ * @param[in] msg - The org.freedesktop.DBus.PropertiesChanged
+ * message.
+ * @param[in] path - The path associated with the message.
+ * @param[in] interface - The interface associated with the message.
+ */
+ void propertiesChanged(
+ sdbusplus::message::message& msg,
+ const std::string& path,
+ const std::string& interface) override;
+
+ /** @brief DBus agnostic implementation of interfacesAdded.
+ *
+ * @param[in] path - The path of the properties that changed.
+ * @param[in] interface - The interface of the properties that
+ * changed.
+ * @param[in] properites - The properties that changed.
+ */
+ void propertiesChanged(
+ const std::string& path,
+ const std::string& interface,
+ const PropertiesChanged<T>& properties);
+
+ /** @brief PropertyMatch implementation for PropertyWatchOfType.
+ *
+ * @param[in] msg - The org.freedesktop.DBus.PropertiesChanged
+ * message.
+ */
+ void interfacesAdded(sdbusplus::message::message& msg) override;
+
+ /** @brief DBus agnostic implementation of interfacesAdded.
+ *
+ * @param[in] path - The path of the added interfaces.
+ * @param[in] interfaces - The added interfaces.
+ */
+ void interfacesAdded(
+ const std::string& path,
+ const InterfacesAdded<T>& interfaces);
+};
+
+} // namespace monitoring
+} // namespace dbus
+} // namespace phosphor