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    // Copyright 2018 Developers of the Rand project.
    //
    // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
    // https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
    // <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
    // option. This file may not be copied, modified, or distributed
    // except according to those terms.

    //! Implementation for Windows
    use crate::{error::RTL_GEN_RANDOM_FAILED, Error};

    extern "system" {
        #[link_name = "SystemFunction036"]
        fn RtlGenRandom(RandomBuffer: *mut u8, RandomBufferLength: u32) -> u8;
    }

    pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
        // Prevent overflow of u32
        for chunk in dest.chunks_mut(u32::max_value() as usize) {
            let ret = unsafe { RtlGenRandom(chunk.as_mut_ptr(), chunk.len() as u32) };
            if ret == 0 {
                return Err(RTL_GEN_RANDOM_FAILED);
            }
        }
        Ok(())
    }

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