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Pin and suffering

Mar 28, 2021

34 min #rust · #async

Disclaimer:

async fn in trait has shipped in Rust 1.75, about 2.5 years after this article was written.

I’d like to think that my understanding of “async Rust” has increased over the past year or so. I’m 100% onboard with the basic principle: I would like to handle thousands of concurrent tasks using a handful of threads. That sounds great!

Day 2 (Advent of Code 2020)

Dec 13, 2020

10 min #rust · #advent-of-code

Day 2, Day 2! Woo!

The Advent of Code 2020, Day 2 problem talks about passwords. Sounds familiar.

Basically, our input looks like this:

1-3 a: abcde
1-3 b: cdefg
2-9 c: ccccccccc

Each line contains a “password policy” and a “password”. For the first line, the policy is that the password must contain between 1 and 3 (inclusive) times the letter “a”.

Dynamic symbol resolution

Feb 02, 2020

26 min #os · #assembly · #linux · #rust · #linkers

Let’s pick up where we left off: we had just taught elk to load not only an executable, but also its dependencies, and then their dependencies as well.

We discovered that ld-linux walked the dependency graph breadth-first, and so we did that too. Of course, it’s a little bit overkill since we only have one dependency, but, nevertheless, elk happily loads our executable and its one dependency:

Cleaning up and upgrading third-party crates

Nov 15, 2022

10 min #rust · #cargo-edit · #ftl-infra

The bleeding edge of rustc and clippy

Typically, you’d want a production application to use a stable version of Rust. At the time of this writing, that’s Rust 1.65.0, which stabilizes a bunch of long-awaited features (GATs, let-else, MIR inlining, split debug info, etc.).

Cool Bear's hot tip

For every Rust release, Mara makes a wonderful recap thread on Twitter, on top of the official announcement.

Getting in and out of trouble with Rust futures

Jul 07, 2020

14 min #rust · #async

I started experimenting with asynchronous Rust code back when futures 0.1 was all we had - before async/await. I was a Rust baby then (I’m at least a toddler now), so I quickly drowned in a sea of .and_then, .map_err and Either<A, B>.

But that’s all in the past! I guess!

Now everything is fine, and things go smoothly. For the most part. But even with async/await, there are still some cases where the compiler diagnostics are, just, so much.

Cross-compilation notes

Aug 07, 2014

8 min #linux

I’ll keep updating this article as I go, just to put stuff in all the same place.

Platforms

Cross-compiling for Linux

I’m pretty sure it’s possible to cross-compile for Linux on other OSes, seeing as everything is open-source, but I have never done it - and why would I want to? Linux is the friendliest to build on, so it’s better to use it as a build environment.

Running an executable without exec

Jan 12, 2020

22 min #os · #assembly · #linux · #rust

In part 1, we’ve looked at three executables:

sample, an assembly program that prints “hi there” using the write system call.
entry_point, a C program that prints the address of main using printf
The /bin/true executable, probably also a C program (because it’s part of GNU coreutils), and which just exits with code 0.

We noticed that when running entry_point through GDB, it always printed the same address. But when we ran it directly, it printed a different address on every run.

rock 0.9.6 is on the loose!

Feb 20, 2013

9 min #ooc · #gamedev · #programming

Just 8 days after the last release, rock 0.9.6 is out.

To update, run git pull && make rescue as usual. To install from scratch, clone the repo, cd into it, and run make rescue from there - it’ll download the latest bootstrap, compile itself from C, then recompile itself from ooc.

Running rock -V should give you something like this:

rock 0.9.6 codename loki, built on Wed Feb 20 15:09:08 2013

FFI-safe types in Rust, newtypes and MaybeUninit

Sep 30, 2019

12 min #networking · #icmp · #win32 · #rust · #ffi

It’s time to make sup, our own take on ping, use the Win32 APIs to send an ICMP echo. Earlier we discovered that Windows’s ping.exe used IcmpSendEcho2Ex. But for our purposes, the simpler IcmpSendEcho will do just fine.

As we mentioned earlier, it’s provided by IPHLPAPI.dll, and its C declaration is:

IPHLPAPI_DLL_LINKAGE DWORD IcmpSendEcho(
  HANDLE                 IcmpHandle,
  IPAddr                 DestinationAddress,
  LPVOID                 RequestData,
  WORD                   RequestSize,
  PIP_OPTION_INFORMATION RequestOptions,
  LPVOID                 ReplyBuffer,
  DWORD                  ReplySize,
  DWORD                  Timeout
);

Building poppler for Windows

Dec 31, 2021

14 min #build-systems · #pkg-config · #cmake · #ftl-infra

I know what you’re thinking: haven’t we strayed from the whole “content pipeline” theme in this series?

Well… fair. But compiling and distributing software is part of software engineering, and unless you’re in specific circles, I see that taught a lot less than the “just write code and stuff happens” part.

Technically it’s release engineering, but who’s keeping track.