[MISC] Allow user to override process priority class

src/xenia/base/system.h

@@ -27,6 +27,8 @@ void ShutdownAndroidSystem();
 void LaunchWebBrowser(const std::string_view url);
 void LaunchFileExplorer(const std::filesystem::path& path);
 
+bool SetProcessPriorityClass(const uint32_t priority_class);
+
 enum class SimpleMessageBoxType {
   Help,
   Warning,

src/xenia/base/system_android.cc

@@ -294,4 +294,6 @@ void ShowSimpleMessageBox(SimpleMessageBoxType type, std::string_view message) {
   // Java VM for the calling thread is needed.
 }
 
+bool SetProcessPriorityClass(const uint32_t priority_class) { return true; }
+
 }  // namespace xe

src/xenia/base/system_gnulinux.cc

@@ -67,4 +67,6 @@ void ShowSimpleMessageBox(SimpleMessageBoxType type, std::string_view message) {
   }
 }
 
+bool SetProcessPriorityClass(const uint32_t priority_class) { return true; }
+
 }  // namespace xe

src/xenia/base/system_win.cc

@@ -7,6 +7,7 @@
  ******************************************************************************
  */
 
+#include <map>
 #include "xenia/base/platform_win.h"
 #include "xenia/base/string.h"
 #include "xenia/base/system.h"
@@ -48,4 +49,19 @@ void ShowSimpleMessageBox(SimpleMessageBoxType type,
               type_flags);
 }
 
+static std::map<const uint32_t, DWORD> xeniaToWindowsPriorityClassMapping = {
+    {0, NORMAL_PRIORITY_CLASS},
+    {1, ABOVE_NORMAL_PRIORITY_CLASS},
+    {2, HIGH_PRIORITY_CLASS},
+    {3, REALTIME_PRIORITY_CLASS}};
+
+bool SetProcessPriorityClass(const uint32_t priority_class) {
+  if (!xeniaToWindowsPriorityClassMapping.count(priority_class)) {
+    return false;
+  }
+
+  return SetPriorityClass(GetCurrentProcess(),
+                          xeniaToWindowsPriorityClassMapping[priority_class]);
+}
+
 }  // namespace xe