Cstring from_raw and into_raw safety precisions by poliorcetics · Pull Request #72963 · rust-lang/rust (original) (raw)

Fixes #48525.
Fixes #68456.

This issue had two points:

• The one about from_raw has been addressed (I hope).
• The other one, about into_raw, has only been partially fixed.

About into_raw: the idea was to:

steer users away from using the pattern of CString::{into_raw,from_raw} when interfacing with C APIs that may change the effective length of the string by writing interior NULs or erasing the final NUL

I tried making a Vec<c_char> like suggested but my current solution feels very unsafe and hacky to me (most notably the type cast), I included it here to make it available for discussion:

fn main() { use std::os::raw::c_char;

let v = String::from("abc")
    .bytes()
    // From u8 to i8,
    // I feel like it will be a problem for values of u8 > 255
    .map(|c| c as c_char)
    .collect::<Vec<_>>();

dbg!(v);

}