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//! Rust implementation of C library function `strlen`
//!
//! Copyright (c) Jonathan 'theJPster' Pallant 2019
//! Licensed under the Blue Oak Model Licence 1.0.0
use crate::CChar;
/// Rust implementation of C library function `strlen`
#[cfg_attr(feature = "strlen", no_mangle)]
pub unsafe extern "C" fn strlen(mut s: *const CChar) -> usize {
let mut result = 0;
while *s != 0 {
s = s.offset(1);
result += 1;
}
result
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn test1() {
assert_eq!(unsafe { strlen(b"Hello\0" as *const CChar) }, 5);
}
#[test]
fn test2() {
assert_eq!(unsafe { strlen(b"\0" as *const CChar) }, 0);
}
#[test]
fn test3() {
assert_eq!(unsafe { strlen(b"X\0" as *const CChar) }, 1);
}
}