frame: store borrowed values

[famfo]

Reduces the amount of some allocations. I am aware that this is a breaking change but in my application this takes out a large chunk of them and now I'm mainly waiting for syscalls ^^'

Maybe it could be a possibility to pre-allocate the entire serialization buffer as well, I'd do that in a separate PR though if I end up looking into that more.

---

• Have you test the code?
• Have you check that the existing tests are passing?
• The destination branch is develop?

[chantra]

I am very much looking for this, this was something I had in mind. I will try to test the change.

[nbari]

Hi @famfo, @chantra, out of curiosity, what are you using this for? (my use case is mainly logging)

[famfo]

I've contributed HAProxy SPOA support for iocaine using this

[chantra]

I use it to capture the ja4 of requests we are receiving. This was a use-case to evaluate if it was a valuable solution. We are planning to use it to put some of the internal custom decision tree that can't be done in haproxy into SPOP.