Struct exrng::ExternalRng

pub struct ExternalRng {
    pub rng_bytes: [u8; 32],
    pub len: usize,
}

ExternalRng has all features But use external random source

Fields

rng_bytes: [u8; 32]

bytes to receive external rng when init

len: usize

lenght of RNG

Methods

impl ExternalRng

pub fn copy_into_array<A, T>(slice: &[T]) -> A where
    A: Default + AsMut<[T]>,
    T: Copy, 

for no std env if want to convert slice to array

Inputs

• 'slice' is a slice from raw part

returns

• array from slice

Examples

use rand_core::{CryptoRng,RngCore};
use exrng::ExternalRng;
fn main(){
use core::slice;
let rng_bytes:[u8;32] = [1u8;32];
let random_ptr: *const u8 = rng_bytes.as_ptr();
let r:&[u8] = unsafe {slice::from_raw_parts(random_ptr, 32)};
let mut rng = ExternalRng {rng_bytes:ExternalRng::copy_into_array(r),len:32};
let mut zero = [0u8; 32];
rng.fill_bytes(&mut zero);
assert_eq!([1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], &zero[..]);
}

Trait Implementations

impl Debug for ExternalRng

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Clone for ExternalRng

fn clone(&self) -> ExternalRng

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl RngCore for ExternalRng

implement Trait RngCore for EnternalRng foucus on fill_bytes

fn next_u32(&mut self) -> u32

Return the next random u32.

fn next_u64(&mut self) -> u64

Return the next random u64.

fn fill_bytes(&mut self, dest: &mut [u8])

Fill dest with random data.

fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error>

Fill dest entirely with random data.

impl CryptoRng for ExternalRng

implement Trait CryptoRng for EnternalRng empty implement