Simplify SDLWrap with NonNull

Source/utils/sdl_wrap.h

@@ -14,31 +14,27 @@ namespace devilution {
 
 namespace SDLWrap {
 
-inline SDLSurfaceUniquePtr CreateRGBSurface(Uint32 flags, int width, int height, int depth, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask)
+template <typename T>
+T NonNull(T x)
 {
-	SDLSurfaceUniquePtr ret { SDL_CreateRGBSurface(flags, width, height, depth, Rmask, Gmask, Bmask, Amask) };
-	if (ret == nullptr)
+	if (x == nullptr)
 		ErrSdl();
+	return x;
+}
 
-	return ret;
+inline SDLSurfaceUniquePtr CreateRGBSurface(Uint32 flags, int width, int height, int depth, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask)
+{
+	return SDLSurfaceUniquePtr { NonNull(SDL_CreateRGBSurface(flags, width, height, depth, Rmask, Gmask, Bmask, Amask)) };
 }
 
 inline SDLSurfaceUniquePtr CreateRGBSurfaceWithFormat(Uint32 flags, int width, int height, int depth, Uint32 format)
 {
-	SDLSurfaceUniquePtr ret { SDL_CreateRGBSurfaceWithFormat(flags, width, height, depth, format) };
-	if (ret == nullptr)
-		ErrSdl();
-
-	return ret;
+	return SDLSurfaceUniquePtr { NonNull(SDL_CreateRGBSurfaceWithFormat(flags, width, height, depth, format)) };
 }
 
 inline SDLSurfaceUniquePtr CreateRGBSurfaceWithFormatFrom(void *pixels, int width, int height, int depth, int pitch, Uint32 format)
 {
-	SDLSurfaceUniquePtr ret { SDL_CreateRGBSurfaceWithFormatFrom(pixels, width, height, depth, pitch, format) };
-	if (ret == nullptr)
-		ErrSdl();
-
-	return ret;
+	return SDLSurfaceUniquePtr { NonNull(SDL_CreateRGBSurfaceWithFormatFrom(pixels, width, height, depth, pitch, format)) };
 }
 
 #ifndef USE_SDL1
@@ -47,42 +43,26 @@ inline SDLSurfaceUniquePtr ConvertSurface(SDL_Surface *src, const SDL_PixelForma
 inline SDLSurfaceUniquePtr ConvertSurface(SDL_Surface *src, SDL_PixelFormat *fmt, Uint32 flags)
 #endif
 {
-	SDLSurfaceUniquePtr ret { SDL_ConvertSurface(src, fmt, flags) };
-	if (ret == nullptr)
-		ErrSdl();
-
-	return ret;
+	return SDLSurfaceUniquePtr { NonNull(SDL_ConvertSurface(src, fmt, flags)) };
 }
 
 #ifndef USE_SDL1
 inline SDLSurfaceUniquePtr ConvertSurfaceFormat(SDL_Surface *src, Uint32 pixel_format, Uint32 flags)
 {
-	SDLSurfaceUniquePtr ret { SDL_ConvertSurfaceFormat(src, pixel_format, flags) };
-	if (ret == nullptr)
-		ErrSdl();
-
-	return ret;
+	return SDLSurfaceUniquePtr { NonNull(SDL_ConvertSurfaceFormat(src, pixel_format, flags)) };
 }
 #endif
 
 #ifndef USE_SDL1
 inline SDLTextureUniquePtr CreateTexture(SDL_Renderer *renderer, Uint32 format, int access, int w, int h)
 {
-	SDLTextureUniquePtr ret { SDL_CreateTexture(renderer, format, access, w, h) };
-	if (ret == nullptr)
-		ErrSdl();
-
-	return ret;
+	return SDLTextureUniquePtr { NonNull(SDL_CreateTexture(renderer, format, access, w, h)) };
 }
 #endif
 
 inline SDLPaletteUniquePtr AllocPalette(int ncolors)
 {
-	SDLPaletteUniquePtr ret { SDL_AllocPalette(ncolors) };
-	if (ret == nullptr)
-		ErrSdl();
-
-	return ret;
+	return SDLPaletteUniquePtr { NonNull(SDL_AllocPalette(ncolors)) };
 }
 
 } //namespace SDLWrap