RAUC: Query RAUC slot status via D-Bus
We are going to provide some of the RAUC features via sysrepo (i.e.,
query the current slot status, install software update, ...).
This commit adds support for reading slot status from RAUC D-Bus API.
[1] https://rauc.readthedocs.io/en/v1.4/using.html#using-the-d-bus-api
Change-Id: I5d3a6b703e7f5dad3a3c3b432392816a84d884d2
diff --git a/src/system/RAUC.cpp b/src/system/RAUC.cpp
new file mode 100644
index 0000000..425b50e
--- /dev/null
+++ b/src/system/RAUC.cpp
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2021 CESNET, https://photonics.cesnet.cz/
+ *
+ * Written by Tomáš Pecka <tomas.pecka@fit.cvut.cz>
+ *
+ */
+#include "RAUC.h"
+#include "utils/log.h"
+
+namespace {
+
+const std::string INTERFACE = "de.pengutronix.rauc.Installer";
+const std::string BUS = "de.pengutronix.rauc";
+const std::string OBJPATH = "/";
+
+std::variant<std::string, uint64_t, uint32_t> sdbusVariantToCPPVariant(const sdbus::Variant& v)
+{
+ // see https://www.freedesktop.org/software/systemd/man/sd_bus_message_read.html
+ auto peek = v.peekValueType();
+
+ // so far (v1.4), RAUC uses only these types
+ if (peek == "s") {
+ return v.get<std::string>();
+ } else if (peek == "u") {
+ return v.get<uint32_t>();
+ } else if (peek == "t") {
+ return v.get<uint64_t>();
+ }
+
+ throw std::invalid_argument("Unimplemented sdbus::variant type readout.");
+}
+
+}
+
+namespace velia::system {
+
+RAUC::RAUC(sdbus::IConnection& connection)
+ : m_dbusObjectProxy(sdbus::createProxy(connection, BUS, OBJPATH))
+ , m_log(spdlog::get("system"))
+{
+}
+
+/** @brief Get current primary slot.
+ *
+ * RAUC's DBus GetPrimary method wrapper.
+ * See https://rauc.readthedocs.io/en/v1.4/reference.html#the-getprimary-method).
+ */
+std::string RAUC::primarySlot() const
+{
+ std::string primarySlot;
+ m_dbusObjectProxy->callMethod("GetPrimary").onInterface(INTERFACE).storeResultsTo(primarySlot);
+ return primarySlot;
+}
+
+/** @brief Get current status of all slots.
+ *
+ * RAUC's DBus GetSlotStatus method wrapper.
+ * The return value is restructualized from sdbus++ data structures to C++ data structures.
+ * (see https://rauc.readthedocs.io/en/v1.4/reference.html#gdbus-method-de-pengutronix-rauc-installer-getslotstatus)
+ */
+std::map<std::string, RAUC::SlotProperties> RAUC::slotStatus() const
+{
+ std::vector<sdbus::Struct<std::string, std::map<std::string, sdbus::Variant>>> slots;
+ m_dbusObjectProxy->callMethod("GetSlotStatus").onInterface(INTERFACE).storeResultsTo(slots);
+
+ std::map<std::string, SlotProperties> res;
+ for (const auto& slot : slots) {
+ SlotProperties status;
+
+ for (const auto& [key, val] : std::get<1>(slot)) {
+ status.insert(std::make_pair(key, sdbusVariantToCPPVariant(val)));
+ }
+
+ res.insert(std::make_pair(std::get<0>(slot), status));
+ }
+
+ return res;
+}
+
+}