refactor: simplify tr_sessionLoadSettings() args (#7935)

* refactor: remove unused appname arg from tr_sessionLoadSettings()

* refactor: swap order of arguments to tr_sessionLoadSettings()
  so way the optional arg can go at the end

cli/cli.cc

@@ -326,7 +326,7 @@ int tr_main(int argc, char* argv[])
 
     /* load the defaults from config file + libtransmission defaults */
     auto const config_dir = getConfigDir(argc, (char const**)argv);
-    auto settings = tr_sessionLoadSettings(nullptr, config_dir.c_str(), MyConfigName);
+    auto settings = tr_sessionLoadSettings(config_dir);
 
     /* the command line overrides defaults */
     if (parseCommandLine(&settings, argc, (char const**)argv) != 0)

daemon/daemon.cc

@@ -402,7 +402,7 @@ tr_variant load_settings(char const* config_dir)
     app_defaults_map.try_emplace(TR_KEY_start_paused, false);
     app_defaults_map.try_emplace(TR_KEY_pidfile, tr_variant::unmanaged_string(""sv));
     auto const app_defaults = tr_variant{ std::move(app_defaults_map) };
-    return tr_sessionLoadSettings(&app_defaults, config_dir, MyName);
+    return tr_sessionLoadSettings(config_dir, &app_defaults);
 }
 
 } // namespace

gtk/Prefs.cc

@@ -108,7 +108,7 @@ tr_variant& getPrefs()
     if (!settings.has_value())
     {
         auto const app_defaults = get_default_app_settings();
-        settings.merge(tr_sessionLoadSettings(&app_defaults, gl_confdir.c_str(), nullptr));
+        settings.merge(tr_sessionLoadSettings(gl_confdir, &app_defaults));
         ensure_sound_cmd_is_a_list(&settings);
     }
 

libtransmission/session.cc

@@ -479,23 +479,21 @@ tr_variant tr_sessionGetSettings(tr_session const* session)
     return settings;
 }
 
-tr_variant tr_sessionLoadSettings(tr_variant const* app_defaults, char const* config_dir, char const* app_name)
+tr_variant tr_sessionLoadSettings(std::string_view const config_dir, tr_variant const* const app_defaults)
 {
+    // start with session defaults...
     auto settings = tr_sessionGetDefaultSettings();
 
-    // if app defaults are provided, override libtransmission defaults
+    // ...app defaults (if provided) override session defaults...
     if (app_defaults != nullptr && app_defaults->holds_alternative<tr_variant::Map>())
     {
         settings.merge(*app_defaults);
     }
 
-    // if a settings file exists, use it to override the defaults
+    // ...and settings.json (if available) override the defaults
-    if (auto const filename = fmt::format(
+    if (auto const filename = fmt::format("{:s}/settings.json", config_dir); tr_sys_path_exists(filename))
-            "{:s}/settings.json",
-            config_dir != nullptr ? config_dir : tr_getDefaultConfigDir(app_name));
-        tr_sys_path_exists(filename))
     {
-        if (auto file_settings = tr_variant_serde::json().parse_file(filename); file_settings)
+        if (auto const file_settings = tr_variant_serde::json().parse_file(filename))
         {
             settings.merge(*file_settings);
         }
@@ -563,7 +561,7 @@ tr_session* tr_sessionInit(char const* config_dir, bool message_queueing_enabled
     // - client settings
     // - previous session's values in settings.json
     // - hardcoded defaults
-    auto settings = tr_sessionLoadSettings(nullptr, config_dir, nullptr);
+    auto settings = tr_sessionLoadSettings(config_dir);
     settings.merge(client_settings);
 
     // if logging is desired, start it now before doing more work

libtransmission/transmission.h

@@ -179,15 +179,14 @@ tr_variant tr_sessionGetSettings(tr_session const* session);
  *
  * TODO: if we ever make libtransmissionapp, this would go there.
  *
- * @param app_defaults tr_variant containing the app defaults
  * @param config_dir the configuration directory to find settings.json
- * @param app_name if config_dir is empty, app_name is used to find the default dir.
+ * @param app_defaults optional tr_variant containing the app-specific defaults
  * @return the loaded settings
  * @see `tr_sessionGetDefaultSettings()`
  * @see `tr_sessionInit()`
  * @see `tr_sessionSaveSettings()`
  */
-tr_variant tr_sessionLoadSettings(tr_variant const* app_defaults, char const* config_dir, char const* app_name);
+[[nodiscard]] tr_variant tr_sessionLoadSettings(std::string_view config_dir, tr_variant const* app_defaults = nullptr);
 
 /**
  * Add the session's configuration settings to the benc dictionary

qt/Prefs.cc

@@ -238,7 +238,7 @@ Prefs::Prefs(QString config_dir)
 #endif
 
     auto const app_defaults = get_default_app_settings();
-    auto settings = tr_sessionLoadSettings(&app_defaults, config_dir_.toUtf8().constData(), nullptr);
+    auto settings = tr_sessionLoadSettings(config_dir_.toStdString(), &app_defaults);
     ensureSoundCommandIsAList(&settings);
 
     for (int i = 0; i < PREFS_COUNT; ++i)

qt/Session.cc

@@ -371,7 +371,7 @@ void Session::start()
     }
     else
     {
-        auto const settings = tr_sessionLoadSettings(nullptr, config_dir_.toUtf8().constData(), "qt");
+        auto const settings = tr_sessionLoadSettings(config_dir_.toStdString());
         session_ = tr_sessionInit(config_dir_.toUtf8().constData(), true, settings);
 
         rpc_.start(session_);