core/settings: Move configuring_global behind an API

Rather than have directly modified global state here, we can make it an
implementation detail and have an interface that changes are queried
through.

src/core/settings.cpp

@@ -14,7 +14,7 @@
 namespace Settings {
 
 Values values = {};
-bool configuring_global = true;
+static bool configuring_global = true;
 
 std::string GetTimeZoneString() {
     static constexpr std::array timezones{
@@ -81,11 +81,12 @@ void LogSettings() {
     log_setting("Services_BCATBoxcatLocal", values.bcat_boxcat_local);
 }
 
-float Volume() {
-    if (values.audio_muted) {
-        return 0.0f;
-    }
-    return values.volume.GetValue();
+bool IsConfiguringGlobal() {
+    return configuring_global;
+}
+
+void SetConfiguringGlobal(bool is_global) {
+    configuring_global = is_global;
 }
 
 bool IsGPULevelExtreme() {
@@ -97,6 +98,13 @@ bool IsGPULevelHigh() {
            values.gpu_accuracy.GetValue() == GPUAccuracy::High;
 }
 
+float Volume() {
+    if (values.audio_muted) {
+        return 0.0f;
+    }
+    return values.volume.GetValue();
+}
+
 void RestoreGlobalState() {
     // If a game is running, DO NOT restore the global settings state
     if (Core::System::GetInstance().IsPoweredOn()) {

src/core/settings.h

@@ -33,8 +33,6 @@ enum class CPUAccuracy {
     DebugMode = 2,
 };
 
-extern bool configuring_global;
-
 template <typename Type>
 class Setting final {
 public:
@@ -198,13 +196,18 @@ struct Values {
 
     // Add-Ons
     std::map<u64, std::vector<std::string>> disabled_addons;
-} extern values;
+};
 
-float Volume();
+extern Values values;
+
+bool IsConfiguringGlobal();
+void SetConfiguringGlobal(bool is_global);
 
 bool IsGPULevelExtreme();
 bool IsGPULevelHigh();
 
+float Volume();
+
 std::string GetTimeZoneString();
 
 void Apply();