Migrate logger to use a callable initialisation/destruction routine

Fixes #39

src/citra/citra.cpp

@@ -129,6 +129,8 @@ static void InitializeLogging() {
 
 /// Application entry point
 int main(int argc, char** argv) {
+    Log::Init();
+
     Config config;
     int option_index = 0;
     bool use_gdbstub = Settings::values.use_gdbstub;

src/citra_libretro/citra_libretro.cpp

@@ -40,6 +40,7 @@ CitraLibRetro* emu_instance;
 
 void retro_init() {
     emu_instance = new CitraLibRetro();
+    Log::Init();
     Log::SetGlobalFilter(emu_instance->log_filter);
 
     // Check to see if the frontend is providing us with logging functionality
@@ -64,6 +65,8 @@ void retro_deinit() {
     LibRetro::Input::Shutdown();
 
     delete emu_instance;
+
+    Log::Destroy();
 }
 
 unsigned retro_api_version() {

src/citra_qt/main.cpp

@@ -1680,6 +1680,15 @@ int main(int argc, char* argv[]) {
     setlocale(LC_ALL, "C");
 
     GMainWindow main_window;
+    Log::Init();
+
+    // After settings have been loaded by GMainWindow, apply the filter
+    Log::Filter log_filter;
+    log_filter.ParseFilterString(Settings::values.log_filter);
+    Log::SetGlobalFilter(log_filter);
+    FileUtil::CreateFullPath(FileUtil::GetUserPath(D_LOGS_IDX));
+    Log::AddBackend(
+        std::make_unique<Log::FileBackend>(FileUtil::GetUserPath(D_LOGS_IDX) + LOG_FILE));
 
     // Register CameraFactory
     Camera::RegisterFactory("image", std::make_unique<Camera::StillImageCameraFactory>());

src/common/logging/backend.cpp

@@ -29,10 +29,6 @@ namespace Log {
  */
 class Impl {
 public:
-    static Impl& Instance() {
-        static Impl backend;
-        return backend;
-    }
 
     Impl(Impl const&) = delete;
     const Impl& operator=(Impl const&) = delete;
@@ -116,6 +112,16 @@ private:
     Filter filter;
 };
 
+std::unique_ptr<Impl> g_logger;
+
+void Init() {
+    g_logger = std::make_unique<Impl>();
+}
+
+void Destroy() {
+    g_logger = nullptr;
+}
+
 void ConsoleBackend::Write(const Entry& entry) {
     PrintMessage(entry);
 }
@@ -263,32 +269,31 @@ Entry CreateEntry(Class log_class, Level log_level, const char* filename, unsign
 }
 
 void SetGlobalFilter(const Filter& filter) {
-    Impl::Instance().SetGlobalFilter(filter);
+    g_logger->SetGlobalFilter(filter);
 }
 
 void AddBackend(std::unique_ptr<Backend> backend) {
-    Impl::Instance().AddBackend(std::move(backend));
+    g_logger->AddBackend(std::move(backend));
 }
 
 void RemoveBackend(std::string_view backend_name) {
-    Impl::Instance().RemoveBackend(backend_name);
+    g_logger->RemoveBackend(backend_name);
 }
 
 Backend* GetBackend(std::string_view backend_name) {
-    return Impl::Instance().GetBackend(backend_name);
+    return g_logger->GetBackend(backend_name);
 }
 
 void FmtLogMessageImpl(Class log_class, Level log_level, const char* filename,
                        unsigned int line_num, const char* function, const char* format,
                        const fmt::format_args& args) {
-    auto& instance = Impl::Instance();
-    const auto& filter = instance.GetGlobalFilter();
+    auto filter = g_logger->GetGlobalFilter();
     if (!filter.CheckMessage(log_class, log_level))
         return;
 
     Entry entry =
         CreateEntry(log_class, log_level, filename, line_num, function, fmt::vformat(format, args));
 
-    instance.PushEntry(std::move(entry));
+    g_logger->PushEntry(std::move(entry));
 }
 } // namespace Log

src/common/logging/backend.h

@@ -104,6 +104,10 @@ private:
     std::size_t bytes_written;
 };
 
+void Init();
+
+void Destroy();
+
 void AddBackend(std::unique_ptr<Backend> backend);
 
 void RemoveBackend(std::string_view backend_name);