sync() after write to avoid losing file data on power off.

PiPedalCommon/src/include/ConfigSerializer.hpp

@@ -30,6 +30,7 @@
 #include "autoptr_vector.h"
 #include <unordered_map>
 #include <fstream>
+#include "ofstream_synced.hpp"
 
 namespace config_serializer
 {
@@ -256,7 +257,7 @@ namespace config_serializer
         }
         void Save(const std::string &path)
         {
-            std::ofstream f;
+            pipedal::ofstream_synced f;
             f.open(path);
             if (!f.is_open())
             {

PiPedalCommon/src/include/ofstream_synced.hpp

@@ -0,0 +1,26 @@
+
+#pragma once
+
+#include <fstream>
+
+namespace pipedal
+{
+    void FileSystemSync();
+
+    class ofstream_synced : public std::ofstream
+    {
+    public:
+        ofstream_synced() {}
+
+        explicit ofstream_synced(const std::string &filename, ios_base::openmode mode = ios_base::out)
+            : std::ofstream(filename, mode)
+        {
+        }
+        explicit ofstream_synced(const char *filename, ios_base::openmode mode = ios_base::out)
+            : std::ofstream(filename, mode)
+        {
+        }
+        ~ofstream_synced();
+    };
+
+}