fastgame_apply: monitoring the removal of the presets file and exitti…

…ng accordingly

src/fastgame_apply.cpp

@@ -6,6 +6,7 @@
 #include <boost/property_tree/json_parser.hpp>
 #include <boost/property_tree/ptree.hpp>
 #include <boost/property_tree/ptree_fwd.hpp>
+#include <chrono>
 #include <cstdint>
 #include <filesystem>
 #include <fstream>
@@ -342,7 +343,21 @@ auto main([[maybe_unused]] int argc, [[maybe_unused]] char* argv[]) -> int {
 
   // nl->new_exit.connect([&](int pid) {});
 
+  auto check_lock_file = [&]() {
+    while (std::filesystem::is_regular_file(input_file)) {
+      std::this_thread::sleep_for(std::chrono::seconds(1));
+    }
+
+    util::info("The lock file has been removed. Exitting the lock thread.");
+
+    nl->listen = false;
+  };
+
   if (nl->listen) {
+    std::thread t(check_lock_file);
+
+    t.detach();
+
     nl->handle_events();  // This is a blocking call. It has to be started at the end
 
     util::info("Netlink event monitor finished.");