Trait CStrLike

Source

pub trait CStrLike {
    // Required methods
    fn as_ptr(&self) -> *const c_char;
    fn as_cstr(&self) -> &CStr;
}

Expand description

A common interface for C-compatible string types used in this crate.

CStrLike abstracts over different string storage strategies (e.g. stack-allocated and heap-allocated C strings) so they can be used interchangeably.

Types that implement this trait guarantee:

The returned pointer from [as_ptr] is a valid, null-terminated C string for as long as the implementor is alive.
The returned CStr reference from [as_cstr] is always valid.

This trait is mainly intended to unify [CStrHeap] (heap-allocated) and CStrStack<N> (stack-allocated with a fixed buffer).

§Examples

use std::ffi::{CString, CStr};
use stack_cstr::{CStrHeap, CStrLike};

let cstr = CString::new("hello").unwrap();
let heap = CStrHeap::new(cstr);

// Use the trait methods
let ptr = heap.as_ptr();
let slice: &CStr = heap.as_cstr();

assert_eq!(slice.to_str().unwrap(), "hello");
unsafe {
    assert_eq!(CStr::from_ptr(ptr).to_str().unwrap(), "hello");
}