linux-kernel - Re: [PATCH v2 next 04/11] tools/nolibc/printf: Output pad characters in 16 byte chunks

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Message-ID: <aYeUvCECL1HQpIi_@1wt.eu>
Date: Sat, 7 Feb 2026 20:38:36 +0100
From: Willy Tarreau <w@....eu>
To: david.laight.linux@...il.com
Cc: Thomas Weißschuh <linux@...ssschuh.net>,
        linux-kernel@...r.kernel.org, Cheng Li <lechain@...il.com>
Subject: Re: [PATCH v2 next 04/11] tools/nolibc/printf: Output pad characters
 in 16 byte chunks

On Fri, Feb 06, 2026 at 07:11:14PM +0000, david.laight.linux@...il.com wrote:
> From: David Laight <david.laight.linux@...il.com>
> 
> Simple to do and saves calls to the callback function.

+20 bytes here but OK for me.

> Signed-off-by: David Laight <david.laight.linux@...il.com>

Acked-by: Willy Tarreau <w@....eu>

> ---
> 
> Changes for v2:
> Formally patch 3, unchanged.
> 
>  tools/include/nolibc/stdio.h | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h
> index 552f09d51d82..c044a6b3babe 100644
> --- a/tools/include/nolibc/stdio.h
> +++ b/tools/include/nolibc/stdio.h
> @@ -355,10 +355,12 @@ int __nolibc_printf(__nolibc_printf_cb cb, void *state, const char *fmt, va_list
>  			outstr = fmt;
>  			len = ofs - 1;
>  		flush_str:
> -			while (width-- > len) {
> -				if (cb(state, " ", 1) != 0)
> +			while (width > len) {
> +				unsigned int pad_len = ((width - len - 1) & 15) + 1;
> +				width -= pad_len;
> +				written += pad_len;
> +				if (cb(state, "                ", pad_len) != 0)
>  					return -1;
> -				written += 1;
>  			}
>  			if (cb(state, outstr, len) != 0)
>  				return -1;

Willy