Compile and Run C in JavaScript(bun.sh) |
Compile and Run C in JavaScript(bun.sh) |
To get it out the door, ended up adding some patches to TinyCC to support .framework on macOS and fix a few things with dlopen and include paths. Also added support for parsing the deprecated attribute used in lots of Darwin headers. C parsers seem a lot simpler than JavaScript which is nice
From my (admittedly limited) knowledge on this space, it seems like this is a straight upgrade over WASM, with the only limiting factor being that your stack is limited to Bun + C. Are there any downsides of this feature when compared with the alternatives mentioned at the start of the article? There are some tradeoffs listed at the bottom but I'm not sure how napi/WASM perform in those aspects either.
But Node now will have some catch up to do. It is already adding support for running Typescript without transpiling it to js first and that's because Bun and Deno provided it first and people saw it was a good idea. Maybe Node will add these things in the future.
Bun: 6.7410ms Bun FFI w/ C: 6.0413ms Node: 5.1307ms C only: 4.3ms (+- 1ms)
I'm generally very bullish on Bun and was very happy with the DX for this C api. Great work to Jarred and the team!!!
benchmark code: https://github.com/tscircuit/bun-ffi-benchmarking
> However, for system libraries, WebAssembly's isolated memory model comes with serious tradeoffs.
> Isolation means no system calls WebAssembly can only access functions the runtime exposes to it. Usually, that's JavaScript.
Without digging into the code I'm going to assume (guess) that this feature did not take the main value-prop of the WASM model.
Afaik, this is explicitly against the isolation that WASM imposes [1]
> Modules must declare all accessible functions and their associated types at load time, even when dynamic linking is used. This allows implicit enforcement of control-flow integrity (CFI) through structured control-flow.
I seem to remember a WASI developer talk that discussed syscalls here, but I can't remember the specifics. The gist was basically along the lines of, "syscalls are a level of privilege that should not be cart-blanche accessible to all programs at all times"
It's worth noting that similar functionality is what allowed PHP to be useful well beyond its original capabilities when companies hit scale and needed more performance out of it. Companies would just write a C module for their critical path code, and load it in as a PHP extension.
An article from Facebook in 2010 about them writing and using a custom C extension for PHP, that was probably the precursor to JSX:
https://www.facebook.com/notes/10158791323777200/
An article from Zend in 2011 about how to write a PHP extension in C:
http://web.archive.org/web/20110222035803/http://devzone.zen...
Anyone that cares about compiling C code should be skilled enough to actually use the right tools in first place.
Not sure what you mean by the right tools in this context.
Secondly, the right tools are having Python, the C and C++ compiler, node-gyp and cmake.js installed, and actually understand how they work.
But what do I know, nowadays folks use C and C++ as scripting languages putting a full library into a single header file to avoid learning how to use the compiler and linker.
https://github.com/holepunchto/bare-abort or https://github.com/holepunchto/bare-buffer
If it is, consider looking in Nim. It compiles to C, and even compiles to Javascript. And is extremely performant while at it.
In addition, it automatically generates wrappers to transparently convert between Javascript's memory model and C's memory model to seamlessly allow Javascript to call upon the C functions imported using it.
Just your usual FFI, really, but with less call overhead than the FFI specification defined by Node (N-API). Albeit with some different tradeoffs made in order to accomplish that.
The thing is, I'm not already using the Bun runtime and wouldn't switch just for this.