Received-SPF: pass (google.com: domain of linux-kernel+bounces-34254-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99;
Date: Mon, 22 Jan 2024 23:38:34 +0100
From: Danilo Krummrich <dakr@redhat.com>
To: Greg KH <gregkh@linuxfoundation.org>
Cc: ojeda@kernel.org, alex.gaynor@gmail.com, wedsonaf@gmail.com,
	boqun.feng@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com,
	benno.lossin@proton.me, a.hindborg@samsung.com,
	aliceryhl@google.com, rust-for-linux@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] rust: str: add to_ascii_{upper,lower}case() to CString
Message-ID: <Za7uampZiG2IP8dE@cassiopeiae>
References: <20240122184608.11863-1-dakr@redhat.com>
 <2024012252-attempt-tables-e3fc@gregkh>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <2024012252-attempt-tables-e3fc@gregkh>

On Mon, Jan 22, 2024 at 11:35:29AM -0800, Greg KH wrote:
> On Mon, Jan 22, 2024 at 07:45:57PM +0100, Danilo Krummrich wrote:
> > Add functions to convert a CString to upper- / lowercase assuming all
> > characters are ASCII encoded.
> > 
> > Signed-off-by: Danilo Krummrich <dakr@redhat.com>
> > ---
> >  rust/kernel/str.rs | 10 ++++++++++
> >  1 file changed, 10 insertions(+)
> > 
> > diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
> > index 7d848b83add4..d21151d89861 100644
> > --- a/rust/kernel/str.rs
> > +++ b/rust/kernel/str.rs
> > @@ -581,6 +581,16 @@ pub fn try_from_fmt(args: fmt::Arguments<'_>) -> Result<Self, Error> {
> >          // exist in the buffer.
> >          Ok(Self { buf })
> >      }
> > +
> > +    /// Converts the whole CString to lowercase.
> > +    pub fn to_ascii_lowercase(&mut self) {
> > +        self.buf.make_ascii_lowercase();
> > +    }
> > +
> > +    /// Converts the whole CString to uppercase.
> > +    pub fn to_ascii_uppercase(&mut self) {
> > +        self.buf.make_ascii_uppercase();
> > +    }
> 
> How are you handling locales?

For ASCII only? Not at all, I guess.

However, std::slice::make_ascii_{lower,upper]case() doesn't seem to handle the
extended range, which tolower() / toupper(), according to _ctype[], does. Do
you mean that?

- Danilo

> 
> thanks,
> 
> greg k-h
>