Added SDL_GetThreadState

src/thread/SDL_thread.c

@@ -456,6 +456,11 @@ void SDL_WaitThread(SDL_Thread *thread, int *status)
     }
 }
 
+SDL_ThreadState SDL_GetThreadState(SDL_Thread *thread)
+{
+    return (SDL_ThreadState)SDL_GetAtomicInt(&thread->state);
+}
+
 void SDL_DetachThread(SDL_Thread *thread)
 {
     if (!thread) {

src/thread/SDL_thread_c.h

@@ -44,14 +44,6 @@
 #endif
 #include "../SDL_error_c.h"
 
-typedef enum SDL_ThreadState
-{
-    SDL_THREAD_STATE_ALIVE,
-    SDL_THREAD_STATE_DETACHED,
-    SDL_THREAD_STATE_ZOMBIE,
-    SDL_THREAD_STATE_CLEANED,
-} SDL_ThreadState;
-
 // This is the system-independent thread info structure
 struct SDL_Thread
 {