Added SDL_GetLoadedModule to do the equivalent of GetModuleHandle/dlload(NOLOAD)

CR: Jorgen

include/SDL_loadso.h

@@ -57,6 +57,16 @@ extern "C" {
  */
 extern DECLSPEC void *SDLCALL SDL_LoadObject(const char *sofile);
 
+/**
+ *  This function returns a handle to an already-loaded shared object and 
+ *  returns a pointer to the object handle. If the object file was not loaded
+ *  the function returns NULL. This function adds a reference to the shared
+ *  object, so the caller should call SDL_UnloadObject when they are finished
+ *  with this reference to ensure that the object can be unloaded.
+ *  The 'sofile' parameter is a system dependent name of the object file.
+ */
+extern DECLSPEC void *SDLCALL SDL_GetLoadedObject(const char *sofile);
+
 /**
  *  Given an object handle, this function looks up the address of the
  *  named function in the shared object and returns it.  This address

src/loadso/dlopen/SDL_sysloadso.c

@@ -41,6 +41,13 @@ SDL_LoadObject(const char *sofile)
     return (handle);
 }
 
+void *
+SDL_GetLoadedObject(const char *sofile)
+{
+	void *handle = dlopen(sofile, RTLD_NOLOAD);
+	return (handle);
+}
+
 void *
 SDL_LoadFunction(void *handle, const char *name)
 {

src/loadso/windows/SDL_sysloadso.c

@@ -46,6 +46,22 @@ SDL_LoadObject(const char *sofile)
     return handle;
 }
 
+void *
+SDL_GetLoadedObject(const char *sofile)
+{
+    LPTSTR tstr = WIN_UTF8ToString(sofile);
+    void *handle = (void *) GetModuleHandle(tstr);
+
+	/* if we got a handle, call LoadLibrary to get
+	*  it again with the ref count incremented.
+	* We do this to match the dlopen version of this function */
+	handle = (void *)LoadLibrary( tstr );
+
+    SDL_free(tstr);
+
+    return handle;
+}
+
 void *
 SDL_LoadFunction(void *handle, const char *name)
 {