ZeroTierOne/rust-zerotier-core/src/portableatomici64.rs

#[cfg(all(target_pointer_width = "32"))]
use std::sync::Mutex;

#[cfg(all(target_pointer_width = "64"))]
use std::sync::atomic::{AtomicI64, Ordering};

// This implements a basic atomic i64 that uses a mutex on 32-bit systems,
// since you can't atomically access something larger than word size.

#[cfg(all(target_pointer_width = "32"))]
pub struct PortableAtomicI64 {
    i: Mutex<i64>
}

#[cfg(all(target_pointer_width = "32"))]
impl PortableAtomicI64 {
    #[inline(always)]
    pub fn new(v: i64) -> PortableAtomicI64 {
        PortableAtomicI64{
            i: Mutex::new(v)
        }
    }

    #[inline(always)]
    pub fn get(&self) -> i64 {
        *self.i.lock().unwrap()
    }

    #[inline(always)]
    pub fn set(&self, v: i64) {
        *self.i.lock().unwrap() = v;
    }
}

#[cfg(all(target_pointer_width = "64"))]
pub struct PortableAtomicI64 {
    i: AtomicI64
}

#[cfg(all(target_pointer_width = "64"))]
impl PortableAtomicI64 {
    #[inline(always)]
    pub fn new(v: i64) -> PortableAtomicI64 {
        PortableAtomicI64{
            i: AtomicI64::new(v)
        }
    }

    #[inline(always)]
    pub fn get(&self) -> i64 {
        self.i.load(Ordering::Relaxed)
    }

    #[inline(always)]
    pub fn set(&self, v: i64) {
        self.i.store(v, Ordering::Relaxed)
    }
}