ding 0.0.0

A DNS client and server library
Documentation 
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use anyhow::Result;
use core::arch::asm;
pub trait Entropy {
    fn entropy(&mut self) -> Result<u128>;
}

pub struct Time;

#[derive(Debug)]
struct Timespec {
    tv_sec: i64,
    tv_nsec: i64,
}

unsafe fn clock_gettime(clock_id: i32, tp: *mut Timespec) -> i32 {
    let mut ret: i32;
    asm!(
        "syscall",
        in("rax") 228,  // __NR_clock_gettime on x86_64
        in("rdi") clock_id,
        in("rsi") tp,
        lateout("rax") ret,
        out("rcx") _,
        out("r11") _,
    );
    ret
}

#[cfg(target_os = "macos")]
unsafe fn clock_gettime(clock_id: i32, tp: *mut Timespec) -> i32 {
    let mut ret: i32;
    asm!(
        "syscall",
        in("rax") 0x2000074,  // SYS_clock_gettime on macOS
        in("rdi") clock_id,
        in("rsi") tp,
        lateout("rax") ret,
        out("rcx") _,
        out("r11") _,
    );
    ret
}

impl Entropy for Time {
    fn entropy(&mut self) -> Result<u128> {
        #[cfg(any(target_os = "macos", target_os = "linux"))]
        {
            let mut entropy: u128 = 0;
            unsafe {
                let ret = clock_gettime(0, &mut entropy as *mut _ as *mut _);
                if ret == 0 {
                    Ok(entropy)
                } else {
                    use anyhow::bail;

                    bail!("failed to get clock time")
                }
            }
        }
    }
}