sgx_tstd/src/sys/rand.rs

// Copyright (c) 2017 Baidu, Inc. All Rights Reserved.
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use core::mem;
use alloc::slice;

pub fn hashmap_random_keys() -> (u64, u64) {
    let mut v = (0, 0);
    unsafe {
        let view = slice::from_raw_parts_mut(&mut v as *mut _ as *mut u8,
                                             mem::size_of_val(&v));
        imp::fill_bytes(view);
    }
    return v
}

mod imp {
    use sgx_types::SgxError;
    use sgx_trts;

    fn getrandom(buf: &mut [u8]) -> SgxError {
        sgx_trts::rsgx_read_rand(buf)
    }

    fn getrandom_fill_bytes(v: &mut [u8]) {
        getrandom(v).expect("unexpected getrandom error");
    }

    #[allow(dead_code)]
    fn is_getrandom_available() -> bool { true }

    pub fn fill_bytes(v: &mut [u8]) {
        getrandom_fill_bytes(v)
    }
}