Date: Wed, 4 Sep 2024 18:42:37 +0200 From: Stefan Esser <se@FreeBSD.org> To: Bob Bishop <rb@gid.co.uk> Cc: "freebsd-hackers@freebsd.org" <freebsd-hackers@FreeBSD.org> Subject: Re: Rust: kernel vs user-space Message-ID: <40836902-cb68-45e0-b4ec-623c21aa47ba@FreeBSD.org> In-Reply-To: <FAB9B773-A51A-4208-A2C9-0CE0604A5235@gid.co.uk> References: <202409031532.483FW0If007252@critter.freebsd.dk> <7533543.20240904114624@yahoo.com> <0.2.0-final-1725440949.866-0xb4bb20@qmda.emu.st> <65ED39B7-099F-43FD-9F53-68286125A65E@FreeBSD.org> <0.2.0-final-1725443552.800-0x2fa4dc@qmda.emu.st> <bd1419b2-5705-4ea6-8238-d98eb072cda0@FreeBSD.org> <FAB9B773-A51A-4208-A2C9-0CE0604A5235@gid.co.uk>
next in thread | previous in thread | raw e-mail | index | archive | help
Am 04.09.24 um 17:21 schrieb Bob Bishop: > Hi, > >> On 4 Sep 2024, at 15:37, Stefan Esser <se@FreeBSD.org> wrote: >> >> Am 04.09.24 um 11:52 schrieb Mark Delany: >>> On 04Sep24, David Chisnall apparently wrote: >>>> There are lots of control-plane things that I'd love to see >>>> written mostly in Lua, >>> It was remiss of me to not mention Lua given that it's already in the project. >>> Yet another language which could make life easier, more productive and more accessible in >>> user-land. >>> I'm not suggesting for an instant that any of these programs need rewriting, but one could >>> imagine that if commands like ifconfig, route, arp, ndp, ipfw (that is, programs which >>> take a lot of user input and do a lot of data manipulation but aren't super-critical on >>> the performance front) were written in a more accessible language, then it might attract >>> new developers without disenfranchising the core C developers. >> >> Here is ldconfig in LUA, written more than 2 years ago, for example: >> >> https://github.com/stesser/ldconfig/blob/main/ldconfig.lua > > And this is better than C because ...? > > (Asking for a friend :-) There had been a request for an architecture independent implementation that works on all FreeBSD releases and architectures. The LUA run-time has been available in FreeBSD for a long time, and it is a stable platform suitable for the implementation of commands that operate on text and might take advantage of features like associative storage. It is a "safe" implementation since memory is automatically managed, which reduces the risk of memory management errors (but we have to trust the LUA interpreter to be free of such issues, instead). I have not made this version available for review (but instead updated the C version to work with hints files of either byte order). But this code is much simpler than the C version it replaces, and it could easily be extended to, e.g., prepare hints files in chroot environments or in images prepared for an architecture with a (possibly) different byte order. And it is not only independent of the byte order and portable over all architectures, but also independent of the FreeBSD version. The LUA version is much shorter and easier to understand (if you know LUA), but one reason not to propose it for inclusion in FreeBSD is that there are many more developers that know how to work on the C version than on the LUA version. David and Mark have mentioned LUA, and there is little LUA code in the base system, currently (mostly the loader). I'd like to see LUA being used for more functionality that is not time critical, and since the LUA language has been very stable over time (other than many other interpreted languages), it is unlikely that a LUA script will not work on a later FreeBSD release (it only depends on a working flua and possibly some LUA include files). Anyway, this is off-topic for the discussion about rust, other than that LUA is a language that is not affected by many bugs that are typical for programs written in C. Best regards, STefan
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?40836902-cb68-45e0-b4ec-623c21aa47ba>