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#![deny(missing_docs)]
extern crate libc;
use libc::funcs::c95::string;
use libc::types::common::c95::c_void;
use libc::types::os::arch::c95::{c_int, size_t};
pub fn memchr(needle: u8, haystack: &[u8]) -> Option<usize> {
let p = unsafe {
string::memchr(
haystack.as_ptr() as *const c_void,
needle as c_int,
haystack.len() as size_t)
};
if p.is_null() {
None
} else {
Some(p as usize - (haystack.as_ptr() as usize))
}
}
#[cfg(test)]
mod tests {
extern crate quickcheck;
use super::memchr;
#[test]
fn matches_one() {
assert_eq!(Some(0), memchr(b'a', b"a"));
}
#[test]
fn matches_begin() {
assert_eq!(Some(0), memchr(b'a', b"aaaa"));
}
#[test]
fn matches_end() {
assert_eq!(Some(4), memchr(b'z', b"aaaaz"));
}
#[test]
fn matches_nul() {
assert_eq!(Some(4), memchr(b'\x00', b"aaaa\x00"));
}
#[test]
fn matches_past_nul() {
assert_eq!(Some(5), memchr(b'z', b"aaaa\x00z"));
}
#[test]
fn no_match_empty() {
assert_eq!(None, memchr(b'a', b""));
}
#[test]
fn no_match() {
assert_eq!(None, memchr(b'a', b"xyz"));
}
#[test]
fn qc_never_fail() {
fn prop(needle: u8, haystack: Vec<u8>) -> bool {
memchr(needle, &haystack); true
}
quickcheck::quickcheck(prop as fn(u8, Vec<u8>) -> bool);
}
}