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#![deny(warnings)]
pub fn cprng_draw(buffer: &mut [u8]) {
unsafe { zx_cprng_draw(buffer.as_mut_ptr(), buffer.len()) };
}
#[link(name = "zircon")]
extern "C" {
fn zx_cprng_draw(buffer: *mut u8, length: usize);
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn cprng() {
let mut buffer = [0; 20];
cprng_draw(&mut buffer);
let mut first_zero = 0;
let mut last_zero = 0;
for _ in 0..30 {
let mut buffer = [0; 20];
cprng_draw(&mut buffer);
if buffer[0] == 0 {
first_zero += 1;
}
if buffer[19] == 0 {
last_zero += 1;
}
}
assert_ne!(first_zero, 30);
assert_ne!(last_zero, 30);
}
#[test]
fn cprng_large() {
let mut buffer = [0; 1024];
cprng_draw(&mut buffer);
for mut s in buffer.chunks_mut(256) {
cprng_draw(&mut s);
}
}
}