Let’s rewrite Linux kernel in Python
Fun fact!
The Asahi Linux drivers for the Apple M1 GPU were originally written in Python: https://asahilinux.org/2022/11/tales-of-the-m1-gpu/
GPU drivers in Python?!
Since getting all these structures right is critical for the GPU to work and the firmware to not crash, I needed a way of quickly experimenting with them while I reverse engineered things. Thankfully, the Asahi Linux project already has a tool for this: The m1n1 Python framework! Since I was already writing a GPU tracer for the m1n1 hypervisor and filling out structure definitions in Python, I decided to just flip it on its head and start writing a Python GPU kernel driver, using the same structure definitions. Python is great for this, since it is very easy to iterate with! Even better, it can already talk the basic RTKit protocols and parse crash logs, and I improved the tools for that so I could see exactly what the firmware was doing when it crashes. This is all done by running scripts on a development machine which connects to the M1 machine via USB, so you can easily reboot it every time you want to test something and the test cycle is very fast!
Good for testing and iterating, but what about performance? Though I guess getting everything right is more important right now, translating it into another language will probably require less work that way
It has already been translated into rust. Python wasn’t ever intended to be used in the “real” driver, but I thought it was a fun anecdote none the less.
No in JavaScript
The prophets have foretold it: https://www.destroyallsoftware.com/talks/the-birth-and-death-of-javascript
Nobody’s built a supercomputer powerful enough to run a python version of even Linux Lite Edition.
Redstone it is, then.
I mean, someone made a barebones Linux work in scratch
Like… Kernel written in scratch?
Yeah, it uses Ed as it’s text editor
Yes and let us build the environment with conda, it’s going to be a fun time!
Fools haven’t even written it well! Translated:
STOP WRITING
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MEMORY WAS NEVER SUPPOSED TO BE AESSED DIRETLY
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YEARS OF PROGRAMMING yet STILL ODE IS STILL WRITTEN with memory vulnerabilities
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Wanted to aess memory diretly anyway? We had a tool for that: It was alled “ASSEMBLY”
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“Yes please give me NULL of something. Please give me *&* of it” - Statements dreamed up by the utterly deranged
LOOK at what Programmers have been demanding your Respet for all this time, with all of the omputers we built for them
(These are REAL programs, written by REAL Programmers):
??? ??? ???
They have played us for absolute fools
what does this omment even say??? i ant see it
LUV ‘ODE
LUV LINUX
‘ATE WINDOWS
‘ATE ‘LOSED SOURCE
SIMPLE AS
Thank
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What language was that jpeg compression written in?
You ever heard of lossless compression? Well they developed lossfull anti compression, it compresses and decompresses the images so many times that the added artifacts create a larger file than original ! Impressive ain’t it?
we do live in the future
Potato
YOU WERE NEVER MEANT TO ACCESS STARCH DIRECTLY
But what if I want a union struct to quickly interpret floats as ints and vice versa! I need my C hacks!
You can’t, C have strict aliasing.
… Which compilers don’t consistently enforce, much like most undefined behavior in C.
How to enforce undefined behavior?
By refusing to compile any code that has undefined behavior. This is what rust’s compiler does, and is simply not possible for a C compiler to do.
To put it another way:
Strict aliasing is an invariant that C compilers assume you as a developer will not violate, and use that assumption to make optimization choices that, if you as the developer have failed to follow the strict aliasing rules, could lead to undefined behavior. So it’s a variant that the compiler expects, but doesn’t enforce at compile time.
I guess it is possible to just disable all such optimizations to get a C compiler that doesn’t create UB just because strict aliasing rules were broken, but there are still many ways that you can trigger UB in C, while safe rust that compiles successfully theoretically has no UB at all.
Strict aliasing exists not for optimization, but for type alignment. You may need more space on stack to save uint32_t than uint8_t[5] because former has 32-bit alignment.
Either way, this is a rule that you as a human are required to follow, and if you fail the compiler is allowed to do anything, including killing your cat.
It’s not a rule that the compiler enforces by failing to build code with undefined behavior.
That is a fundamental, and extremely important, difference between C and rust.
Also, C compilers do make optimization decisions by assuming that you as a human programmer have followed these strict aliasing rules.
https://gist.github.com/shafik/848ae25ee209f698763cffee272a58f8
Has a few examples where code runs “properly” without optimizations but “improperly” with optimizations.
I put “improperly” in quotes because the C spec says that a compiler can do whatever it wants if you as a human invoke undefined behavior. Safe rust does not have undefined behavior, because if you write code which would invoke UB, rustc will refuse to build it.
Compiler knows what is undefined behaviour better than all lemmy experts
Does anyone even know what Windows is written in?
Originally Windows was written in assembly and ran on top of DOS, but since Windows 2000 and XP, it’s been exclusively running on the NT kernel, which is written primarily in C, with some C++ in there as well.
The actual userspace is mostly C++ and C#.
Microsoft is quickly writing more and more Rust code these days. They rolled out Rust kernel components even before Linux, and their efforts actually include rewrites rather than making the API available to developers.
There’s decades of code in Windows, but the successful conversion for DirectWrite font parsing is probably a sign of things to come. MS seems to even be porting some COM modules to Rust, which would be the last thing I would start to port (so many pointer pointers!).
True! Their embrace of Rust is certainly heartening to see.
Let’s just hope they don’t follow it up with the other two E’s in their typical playbook.
Please do go ahead and name the last open standard that Microsoft intentionally destroyed.
EEE is the fucking boogeyman on Lemmy. You just mention it’s name and a bunch of nerds shit their pants and upvote.
Atom died about 13 months ago.
Just because they’re in a relative lull in the desktop space doesn’t mean they’ve stopped.
Atom usage dropped off dramatically in favour of VS Code or the fully open source VS Codium, there’s no point in Github writing it’s own code editor when it’s hosting a much more popular, more powerful, and equally open source editor in one of its repos.
Github had been funding development of Atom until MS bought them, put Atom on maintenance mode for 4 years, then killed it.
There may be good examples out there, but I’d argue Atom isn’t one of them. VS Code was clearly intended to be a spiritual successor with MS branding IMO, it is a fork of Atom, and it is equally open source (MIT license).
Unless I’m missing something, the most recent example there is from 2002 which, to my own horror, was more than 20 years ago.
witchcraft
Makes sense
C or C++ usually
yeah but which craft?
Well, you know those claims that Java runs on 18 trillion devices? How do you think they got there, hmmmmm?
Windows actually came with a Java runtime for a short while. Then Microsoft got sued, the Java VM was killed, and C# was created (which looks, feels, and behaves very similar to Java) as an alternative.
Just imagine what would’ve happened if Microsoft and Sun worked together. Java would be in everything on Windows now, not just as a basis for modded Minecraft.
Computers are so fast now, we should just write everything in BASIC anyway
Welcome to the world of JavaScript
Imagine having anyone tell you how to access your memory.
Search for leak in sudo’s changelog: https://www.sudo.ws/releases/changelog/
Leaks aren’t usually security critical though, and I’ve never heard of sudo triggering the OOM killer.
Also, no general purpose language that I’m aware of can guarantee a lack of memory leaks.
no general purposd language can guarantee a lack of memory leaks
You’re going to summon every Rust enthusiast on the platform
Especially since sudo is generally quite short lived. Unless it is leaking a significant amount of memory waiting for authentication that never comes it is insignificant. It would actually be pretty easy to argue that
sudojust shouldn’t free memory at all. This would be better for security (all pointers live forever) and possibly faster as upon exec the kernel can just wipe all state rather than havingfreecarefully account for the releases.
Do people still think, after all this time and so many different languages, that there will be one language to rule them all? I mean technically you can drive nails with a rock, but you don’t see a carpenter using one. Right tool for the job. Always was, always will be.
Primitive, provincial knuckledragging Americans/Brits/Right-wing country’s citizens don’t want to learn C or understand how their computer truly works. 😆
Yeah. That tracks
C is not how a computer truly works.
If you want to know how computers work, learn assembly and circuit design. You can learn C without ever thinking about registers, register allocation, the program counter, etc.
Although you can learn assembly without ever learning about e.g. branch prediction. There’s tons of levels of abstraction in computers, and many of the lower level ones try to pretend you’ve still got a computer from the 80s even though CPUs are a lot more complex than they used to be.
As an aside, I’ve anecdotally heard of some schools teaching Rust instead of C as a systems language in courses. Rust has a different model than C, but will still teach you about static memory vs the stack vs the heap, pointers, etc.
Honestly, if I had to write some systems software, I’d be way more confident in any Rust code I wrote than C/C++ code. Nasal demons scare me.
w… windows 10?
W10: :(
I think I saw online that Windows was written in C++
C++, but a very ugly and oldschool dialect of it.
Yes, you already said C++, no need to repeat yourself :P
Well… I love C, just the semplicity of the syntax and low level aspect of it makes it the only language you need. F*ck high level languages
C is simple in the same way that a circular saw with no safety features is simple. I like having fingers better.
low level aspect of it makes it the only language you need
about that https://queue.acm.org/detail.cfm?id=3212479
Just use brainfuck for everything. The entry barrier for the programming industry needs to be higher anyway.
Is brainfuck efficient ?
For the programmer? Very no.
For saving space if run via interperter? No.
For running compiled for conventional CPUs? No.
Compared to CISC instruction sets? Absolutely no.
BF might be highly efficient if crunched down to a bit-packed representation (3 bits per instruction) and run on an FPGA that understands it.
For demonstrating to CS freshmen that Turing Completeness isn’t that remarkable of a language feature: very highly efficient.
Can be compressed very efficiently. I do dread the thought of writing a driver in brainfuck.
Why specifically a driver ?
Hardware is complex and mysterious enough without added complexity of an esoteric language.
C is fun. Thats why I use it :P
The same way juggling chainsaws is fun I suppose. :)
I enjoy the selection bias in the comments for these sorts of posts. >_< There’s a few people saying “I kinda like C”, a few saying “use Python instead”, and a whole lot saying “Rust is my lord and savior”. Completely disjoint from the real world usage of the languages for whatever practical, pragmatic, or ideological measures they are used for.
I know barely anything about programming languages and only ask as a fan, what are the real world usages of languages and what are their practical, pragmatic, or ideological measures that they are used for?
I guess by real world usage I mean what proportion of code is being made with them. You should be skeptical of their accuracy, but there are measures for that. Like there is this one: https://www.tiobe.com/tiobe-index/, but it describes it’s methodology as being about popularity based on articles, news, and other such things. Github publishes a very different chart as does RedMonk. Rust barely shows up on these charts, but Rust fans are very enthusiastic in threads like this. I like Rust well enough, but I also find the over-enthusiasm amusing.
By practical/pragmatic I mean the ability to target a lot of hardware with C. Sometimes the tooling is crap, but it’s very universal. Being built on LLVM Rust can go onto plenty of hardware too, but it’s probably not the tooling given to you by a platform vendor. It’s also been around for a long time, so using Rust would mean a rewrite. Sometimes C is simply the choice. As for ideologically: Rust solves some pretty nasty programming issues, but sometimes I think it’s fans over-estimate the percentage of real world problems it actually solves while ignoring that Rust can be more expensive to write. (shrug) Sometimes there’s no such thing as a silver bullet.
I really like C because I can just get to the heart of an action and make it happen without much surrounding code.
I could make classes and blah blah blah if I want to make a large, complex program but I’d rather write several small, simple to grok programs which pass information around so each program can do its one simple thing, quickly and easily. Chain the small programs together with bash or something, and bingo, you’ve got a modular high speed system.
I’m not a programmer, actually a mechanical engineer. But the Unix philosophy of simple, modular tools is great, provided one properly checks and sanitizes inputs.
What you’re describing sounds like Python. Not really C’s strong suit.
If you haven’t checked it out yet, you certainly should!
I agree with your main point. Python does a great job of replacing lots of tiny, chained scripts. Simple API calls with wget or curl have a place, but can spiral out of control quickly if you need to introduce any grain of control like with pagination, as an example.
Maintaining one Python app (or “script”) can still adhere to the unix philosophy of simplicity but can bend some rules as far as monolithic design is concerned if you aren’t careful.
It all boils down to whether you are introducing complexity or reducing it, IMHO.
