DevMgr: Add DeviceReattacher daemon plumbing

This is the plumbing for a periodic polling thread that tries
to reattach DA specs that failed to attach in the startup phase.

smocore/CMakeLists.txt

@@ -25,6 +25,7 @@ add_library(smocore STATIC
 
     # DeviceManager
     deviceManager/deviceManager.cpp
+    deviceManager/deviceReattacher.cpp
     deviceManager/deviceAttachmentPipeSpecParser.cpp
     ${LEX_OUTPUT}
     ${YACC_OUTPUT}

smocore/deviceManager/deviceReattacher.cpp

@@ -0,0 +1,68 @@
+#include <config.h>
+#include <iostream>
+#include <functional>
+#include <componentThread.h>
+#include <deviceManager/deviceReattacher.h>
+#include <deviceManager/deviceManager.h>
+
+namespace smo {
+namespace device {
+
+DeviceReattacher::DeviceReattacher(
+	DeviceManager& parent, std::shared_ptr<ComponentThread> ioThread)
+: parent(parent), ioThread(ioThread), shouldContinue(false),
+timer(ioThread->getIoService())
+{
+}
+
+void DeviceReattacher::start()
+{
+    shouldContinue.store(true);
+    scheduleNextTimeout();
+}
+
+void DeviceReattacher::stop()
+{
+    shouldContinue.store(false);
+    timer.cancel();
+}
+
+void DeviceReattacher::scheduleNextTimeout()
+{
+    if (!shouldContinue.load()) {
+        return;
+    }
+
+    // Schedule the next timeout using the configured period
+    timer.expires_from_now(
+		boost::posix_time::milliseconds(
+			CONFIG_MRNTT_DEVMGR_REATTACHER_PERIOD_MS));
+
+	timer.async_wait(
+		std::bind(&DeviceReattacher::onTimeout, this, std::placeholders::_1));
+}
+
+void DeviceReattacher::onTimeout(const boost::system::error_code& error)
+{
+	// Timer was cancelled, which is expected when stopping
+	if (error == boost::asio::error::operation_aborted) {
+        return;
+    }
+
+    if (error)
+	{
+        std::cerr << "DeviceReattacher: Timer error: " << error.message()
+			<< std::endl;
+        return;
+    }
+
+    if (!shouldContinue.load()) {
+        return;
+    }
+
+    // Schedule the next timeout
+    scheduleNextTimeout();
+}
+
+} // namespace device
+} // namespace smo

smocore/include/deviceManager/deviceReattacher.h

@@ -0,0 +1,44 @@
+#ifndef DEVICEREATTACHER_H
+#define DEVICEREATTACHER_H
+
+#include <atomic>
+#include <memory>
+#include <boost/asio.hpp>
+
+namespace smo {
+
+class ComponentThread;
+
+namespace device {
+
+class DeviceManager;
+
+class DeviceReattacher
+{
+public:
+    DeviceReattacher(
+		DeviceManager& parent, std::shared_ptr<ComponentThread> ioThread);
+    ~DeviceReattacher() = default;
+
+    // Non-copyable
+    DeviceReattacher(const DeviceReattacher&) = delete;
+    DeviceReattacher& operator=(const DeviceReattacher&) = delete;
+
+    // Control methods
+    void start();
+    void stop();
+
+private:
+    void scheduleNextTimeout();
+    void onTimeout(const boost::system::error_code& error);
+
+    DeviceManager &parent;
+    std::shared_ptr<ComponentThread> ioThread;
+    std::atomic<bool> shouldContinue;
+    boost::asio::deadline_timer timer;
+};
+
+} // namespace device
+} // namespace smo
+
+#endif // DEVICEREATTACHER_H