vendor/openssl-0.9.19/src/memcmp.rs

   1 use libc::size_t;
   2 use ffi;
   3
   4 /// Returns `true` iff `a` and `b` contain the same bytes.
   5 ///
   6 /// This operation takes an amount of time dependent on the length of the two
   7 /// arrays given, but is independent of the contents of a and b.
   8 ///
   9 /// # Panics
  10 ///
  11 /// This function will panic the current task if `a` and `b` do not have the same
  12 /// length.
  13 pub fn eq(a: &[u8], b: &[u8]) -> bool {
  14     assert!(a.len() == b.len());
  15     let ret = unsafe {
  16         ffi::CRYPTO_memcmp(
  17             a.as_ptr() as *const _,
  18             b.as_ptr() as *const _,
  19             a.len() as size_t,
  20         )
  21     };
  22     ret == 0
  23 }
  24
  25 #[cfg(test)]
  26 mod tests {
  27     use super::eq;
  28
  29     #[test]
  30     fn test_eq() {
  31         assert!(eq(&[], &[]));
  32         assert!(eq(&[1], &[1]));
  33         assert!(!eq(&[1, 2, 3], &[1, 2, 4]));
  34     }
  35
  36     #[test]
  37     #[should_panic]
  38     fn test_diff_lens() {
  39         eq(&[], &[1]);
  40     }
  41 }