From bb34441474486f64f69c97bddd54f39adaea73ce Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Thu, 5 Jan 2023 00:48:44 -0800
Subject: [PATCH] Provide a better real-world example of the SDL_RWread() API
change
---
docs/README-migration.md | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)
diff --git a/docs/README-migration.md b/docs/README-migration.md
index 1c24459761c2..6b1dfc55ab6e 100644
--- a/docs/README-migration.md
+++ b/docs/README-migration.md
@@ -545,22 +545,21 @@ SDL_RWread() previously returned 0 at end of file or other error. Now it returns
Code that used to look like this:
- if (!SDL_RWread(context, ptr, size, 1)) {
-
... handle error - }
+size_t custom_read(void *ptr, size_t size, size_t nitems, SDL_RWops *stream)
+{
- return (size_t)SDL_RWread(stream, ptr, size, nitems);
+}
should be changed to:
- if (SDL_RWread(context, ptr, size) != size) {
-
... handle error - }
--or, if you're using a custom non-blocking context or are handling variable size data: - - Sint64 amount = SDL_RWread(context, ptr, maxsize);
- if (amount < 0) {
-
... handle error
+size_t custom_read(void *ptr, size_t size, size_t nitems, SDL_RWops *stream)
+{
- Sint64 amount = SDL_RWread(stream, ptr, size * nitems);
- if (amount <= 0) {
-
}return 0; - return (size_t)(amount / size);
+}
Similarly, SDL_RWwrite() can return -2 for data not ready in the case of a non-blocking context. There is currently no way to create a non-blocking context, we have simply defined the semantic for your own custom SDL_RWops object.