From a234470e39d32a071ee92f5888774930de2b5c0d Mon Sep 17 00:00:00 2001
From: Ethan Lee <flibitijibibo@gmail.com>
Date: Sat, 15 May 2021 09:10:02 -0400
Subject: [PATCH] Make all UTF8 conversions nullable.

Trying to avoid null strings was far too invasive and kept creating bugs in the wrapper, and the wrapper should not have enough code to create bugs in the first place.
---
 src/SDL2.cs | 36 +++++++++++-------------------------
 1 file changed, 11 insertions(+), 25 deletions(-)

diff --git a/src/SDL2.cs b/src/SDL2.cs
index 13645cf..b76e6b4 100644
--- a/src/SDL2.cs
+++ b/src/SDL2.cs
@@ -47,24 +47,10 @@ namespace SDL2
 
 		/* Used for stack allocated string marshaling. */
 		internal static int Utf8Size(string str)
-		{
-			Debug.Assert(str != null);
-			return (str.Length * 4) + 1;
-		}
-		internal static int Utf8SizeNullable(string str)
 		{
 			return str != null ? (str.Length * 4) + 1 : 0;
 		}
 		internal static unsafe byte* Utf8Encode(string str, byte* buffer, int bufferSize)
-		{
-			Debug.Assert(str != null);
-			fixed (char* strPtr = str)
-			{
-				Encoding.UTF8.GetBytes(strPtr, str.Length + 1, buffer, bufferSize);
-			}
-			return buffer;
-		}
-		internal static unsafe byte* Utf8EncodeNullable(string str, byte* buffer, int bufferSize)
 		{
 			if (str == null)
 			{
@@ -1234,16 +1220,16 @@ namespace SDL2
 			string message,
 			IntPtr window
 		) {
-			int utf8TitleBufSize = Utf8SizeNullable(title);
+			int utf8TitleBufSize = Utf8Size(title);
 			byte* utf8Title = stackalloc byte[utf8TitleBufSize];
 
-			int utf8MessageBufSize = Utf8SizeNullable(message);
+			int utf8MessageBufSize = Utf8Size(message);
 			byte* utf8Message = stackalloc byte[utf8MessageBufSize];
 
 			return INTERNAL_SDL_ShowSimpleMessageBox(
 				flags,
-				Utf8EncodeNullable(title, utf8Title, utf8TitleBufSize),
-				Utf8EncodeNullable(message, utf8Message, utf8MessageBufSize),
+				Utf8Encode(title, utf8Title, utf8TitleBufSize),
+				Utf8Encode(message, utf8Message, utf8MessageBufSize),
 				window
 			);
 		}
@@ -1497,10 +1483,10 @@ namespace SDL2
 			int h,
 			SDL_WindowFlags flags
 		) {
-			int utf8TitleBufSize = Utf8SizeNullable(title);
+			int utf8TitleBufSize = Utf8Size(title);
 			byte* utf8Title = stackalloc byte[utf8TitleBufSize];
 			return INTERNAL_SDL_CreateWindow(
-				Utf8EncodeNullable(title, utf8Title, utf8TitleBufSize),
+				Utf8Encode(title, utf8Title, utf8TitleBufSize),
 				x, y, w, h,
 				flags
 			);
@@ -1822,7 +1808,7 @@ namespace SDL2
 		);
 		public static unsafe SDL_bool SDL_GL_ExtensionSupported(string extension)
 		{
-			int utf8ExtensionBufSize = Utf8SizeNullable(extension);
+			int utf8ExtensionBufSize = Utf8Size(extension);
 			byte* utf8Extension = stackalloc byte[utf8ExtensionBufSize];
 			return INTERNAL_SDL_GL_ExtensionSupported(
 				Utf8Encode(extension, utf8Extension, utf8ExtensionBufSize)
@@ -8106,16 +8092,16 @@ namespace SDL2
 		);
 		public static unsafe string SDL_GetPrefPath(string org, string app)
 		{
-			int utf8OrgBufSize = Utf8SizeNullable(org);
+			int utf8OrgBufSize = Utf8Size(org);
 			byte* utf8Org = stackalloc byte[utf8OrgBufSize];
 
-			int utf8AppBufSize = Utf8SizeNullable(app);
+			int utf8AppBufSize = Utf8Size(app);
 			byte* utf8App = stackalloc byte[utf8AppBufSize];
 
 			return UTF8_ToManaged(
 				INTERNAL_SDL_GetPrefPath(
-					Utf8EncodeNullable(org, utf8Org, utf8OrgBufSize),
-					Utf8EncodeNullable(app, utf8App, utf8AppBufSize)
+					Utf8Encode(org, utf8Org, utf8OrgBufSize),
+					Utf8Encode(app, utf8App, utf8AppBufSize)
 				),
 				true
 			);