http.zig VS zig

I have a somewhat popular HTTP server library for Zig [1]. It started off as a thread-per-connection (with an optional thread pool), but when it became apparent that async wasn't going to be added back into the language any time soon, I switched to using epoll/kqueue.

Both APIs allow you to associate arbitrary data (void ) with the event that you're registering. So when you're notified of the event, you can access this data. In my case, it's a big Conn struct. It contains things like the # of requests on this connection (to enforce a configured max request per connection), a timestamp where it should timeout if there's no activity. The Conn is part of an intrusive linked list, so it has a next: Conn and prev: *Conn. But, what you're probably most curious about, is that it has a Request.State. This has a static buffer ([]u8) that can grow as needed to hold all the received data up until that point (or if we're writing the data, then the buffered data that we have to write). It's important to have a max # of connections and a max request size so you can enforce an upper limit on the maximum memory the library might use. It acts as a state machine to track up to what point it's parsed the request. (since you don't want to have to re-parse the entire request as more bytes trickle in).

It's all half-baked. I can do receiving/sending asynchronously, but the application handler is called synchronously, and if that, for example, calls PG, that's probably also synchronous (since there's no async PG library in Zig). Makes me feel that any modern language needs a cohensive (as in standard library, or de facto standard) concurrency story.

[1] https://github.com/karlseguin/http.zig

I took a year off, and one of the things I did was learn Zig. I've built a number of libraries, including one of the currently more popular HTTP server libraries (https://github.com/karlseguin/http.zig).

A number of my libraries are used for https://www.aolium.com/ which I decided to write for myself.

I try to write a bit every day with the benefit that I can "waste" time digging into things or exploring likely-to-fail paths.

It's "Zig" not "Zag". https://ziglang.org/ Zig is under heavy development, but there's a single page https://ziglang.org/documentation/0.12.0/ that is a reasonably comprehensive source of truth about the current state of the language.

There is an issue proposing this approach: https://github.com/ziglang/zig/issues/4284

https://github.com/ziglang/zig/issues/224

e.g.:

> > When debugging/prototyping, it's useful to comment out a line without having to refactor, e.g.

When writing code in a scripting language, sometimes you need that extra bit of performance (or maybe an async feature from Zig).

NodeJS is by no means a slow runtime, it wouldn’t be so popular if it was. But compared to Bun, it’s slow. Bun was built from the ground up with speed in mind, using both JavascriptCore and Zig. The Bun team spent an enormous amount of time and energy trying to make Bun fast, including lots of profiling, benchmarking, and optimizations.

ntdll.dll!RtlUserThreadStart()

There are valid reasons to use APIs from NTDLL. Where I disagree with zig#1840 is the idea that it is always better to use NTDLL versions of API. Every other software ecosystem uses the standard Win32 APIs and diverging from that without a good reason seems like a good way to have unexpected behavior. One concrete example is most users and programmers expect Windows to redirect some file system paths when running on WOW64. But this is implemented in Kernel32, not ntdll.

https://github.com/ziglang/zig/issues/11894