Remove variable length arrays about nextvi

[kyx0r]

Not efficient, but possible. replacing VLAs with malloc is fairly straightforward process.

[kyx0r]

Static arrays probably won't work, unless you be willing to make some assumptions and reserve large blocks of memory.

[adriangrigore]

So how would you go about it? I can migrate to malloc, but not sure about sizes for static arrays. Migrate all VLAs to malloc-ed ones?

[adriangrigore]

Here's how nextvi looks on 9front

[kyx0r]

How did you get it to compile?

Actually, changing to static array is rather trivial. Just make 1 global char array with size of 0.5MB-1MB and reference it everywhere its needed. Basically we simulate our own stack. The only case where this would not work is multithreaded code, which does exists if you use the threaded_search.patch. Its optional however.

[adriangrigore]

How did you get it to compile?

I just created static arrays with large sizes, but opened the issue because I was unsure about the sizes.

Actually, changing to static array is rather trivial. Just make 1 global char array with size of 0.5MB-1MB and reference it everywhere its needed. Basically we simulate our own stack. The only case where this would not work is multithreaded code, which does exists if you use the threaded_search.patch. Its optional however.

I might switch to multi threaded code because I'm considering adding mouse support. Where can I find the threaded_search patch?

[adriangrigore]

Any other tips for porting to a multi threaded environment?

[kyx0r]

How did you get it to compile?

I just created static arrays with large sizes, but opened the issue because I was unsure about the sizes.

Ahh, in that case I can tell you that regex would need the most memory.

char nsubs[prog->sub];

nsubs can get quite large.

I might switch to multi threaded code because I'm considering adding mouse support. Where can I find the threaded_search patch?

https://github.com/kyx0r/nextvi/tree/patches

Not sure if multithreading is actually required for mouse though. Because all that mouse is just reading keycodes from the terminal. Not difference from keyboard. Only question if the terminal a universal format for this.

[adriangrigore]

The terminal is not in a standard format. I doesn't support escape codes. This is more of a GUI application than a TUI application in 9front. From what I understand, mouse support requires a multi threaded environment: https://9fans.github.io/plan9port/man/man3/thread.html.
https://wiki.9front.org/programming-gui

This is what term.c would look like on 9front (wip) http://okturing.com/src/17118/body.

[kyx0r]

Any other tips for porting to a multi threaded environment?

I think regex is the most problematic where just making a static array may not cut it. In that case you can add pointers in the rcode structure and malloc them at reg_comp. Then just use those pointers in re_pikevm.

[kyx0r]

Hi, any progress on this? It would be nice to add an optional patch that removes VLA for systems that may benefit from it.