Re: [PATCH] ui/curses: Fix infinite loop on windows

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 3/4/25 03:07, William Hu via wrote:
>  From a42046272f0544dd18ed58661e53ea17d1584c2c Mon Sep 17 00:00:00 2001
> From: William Hu <purplearmadillo77@proton.me>
> Date: Wed, 2 Apr 2025 12:00:00 -0400
> Subject: [PATCH] ui/curses: Fix infinite loop on windows
> 
> Replace -1 comparisons for wint_t with WEOF to fix infinite loop caused by a
> 65535 == -1 comparison.
> 
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2905
> Signed-off-by: William Hu <purplearmadillo77@proton.me>
> ---
>   ui/curses.c | 10 ++++++++--
>   1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/ui/curses.c b/ui/curses.c
> index a39aee8762..3f5c5adf78 100644
> --- a/ui/curses.c
> +++ b/ui/curses.c
> @@ -265,7 +265,12 @@ static int curses2foo(const int _curses2foo[], const int _curseskey2foo[],
>   
>   static void curses_refresh(DisplayChangeListener *dcl)
>   {
> -    int chr, keysym, keycode, keycode_alt;
> +    /*
> +     * DO NOT MAKE chr AN INT:
> +     * Causes silent conversion errors on Windows where wint_t is unsigned short.
> +     */
> +    wint_t chr = 0;
> +    int keysym, keycode, keycode_alt;
>       enum maybe_keycode maybe_keycode = CURSES_KEYCODE;
>   
>       curses_winch_check();
> @@ -284,8 +289,9 @@ static void curses_refresh(DisplayChangeListener *dcl)
>           /* while there are any pending key strokes to process */
>           chr = console_getch(&maybe_keycode);
>   
> -        if (chr == -1)
> +        if (chr == WEOF) {
>               break;
> +        }

Correct but incomplete, also missing the same check few lines below:

-- >8 --
diff --git a/ui/curses.c b/ui/curses.c
index a39aee87623..9c33de331cd 100644
--- a/ui/curses.c
+++ b/ui/curses.c
@@ -304,9 +304,9 @@ static void curses_refresh(DisplayChangeListener *dcl)
          /* alt or esc key */
          if (keycode == 1) {
              enum maybe_keycode next_maybe_keycode = CURSES_KEYCODE;
-            int nextchr = console_getch(&next_maybe_keycode);
+            wint_t nextchr = console_getch(&next_maybe_keycode);

-            if (nextchr != -1) {
+            if (nextchr != WEOF) {
                  chr = nextchr;
                  maybe_keycode = next_maybe_keycode;
                  keycode_alt = ALT;
---

With that:
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>