linux-kernel - Re: [PATCH 7/7] rust: init: add support for arbitrary paths in init macros

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 28 Jun 2023 11:26:54 +0000
From:   Benno Lossin <benno.lossin@...ton.me>
To:     Gary Guo <gary@...yguo.net>
Cc:     Miguel Ojeda <ojeda@...nel.org>,
        Wedson Almeida Filho <wedsonaf@...il.com>,
        Alex Gaynor <alex.gaynor@...il.com>,
        Boqun Feng <boqun.feng@...il.com>,
        Björn Roy Baron <bjorn3_gh@...tonmail.com>,
        Alice Ryhl <aliceryhl@...gle.com>,
        Andreas Hindborg <nmi@...aspace.dk>,
        rust-for-linux@...r.kernel.org, linux-kernel@...r.kernel.org,
        patches@...ts.linux.dev, Asahi Lina <lina@...hilina.net>
Subject: Re: [PATCH 7/7] rust: init: add support for arbitrary paths in init macros

On 25.06.23 23:01, Gary Guo wrote:
> On Sat, 24 Jun 2023 09:25:39 +0000
> Benno Lossin <benno.lossin@...ton.me> wrote:
> 
>> Previously only `ident` and generic types were supported in the
>> `{try_}{pin_}init!` macros. This patch allows arbitrary path fragments,
>> so for example `Foo::Bar` but also very complex paths such as
>> `<Foo as Baz>::Bar::<0, i32>`.
>>
>> Internally this is accomplished by using `path` fragments. Due to some
>> peculiar declarative macro limitations, we have to "forget" certain
>> additional parsing information in the token trees. This is achieved by
>> the new `retokenize` proc macro. It does not modify the input, but just
>> strips this information. For example, if a declarative macro takes
>> `$t:path` as its input, it cannot sensibly propagate this to a macro that
>> takes `$($p:tt)*` as its input, since the `$t` token will only be
>> considered one `tt` token for the second macro. If we first pipe the
>> tokens through `retokenize`, then it parses as expected.
> 
> I think this "retokenize" macro could also be functionally replaced by
> `paste`. Would you mind to apply my paste patch (referenced in a
> previous email) and see if it works?

I tried your patch and it seems to work. I also executed all of the test
in the userspace library and they passed.
The `paste!` code also looks good to me. One thing that I thought was this:
do we want to accept `paste!( [<= foo bar>])`? Because the `<` token has
spacing `Joint`, maybe add a check for that? No idea if that would be a problem.

-- 
Cheers,
Benno

> 
> Best,
> Gary
>