fish-shell/fish-rust/src/global_safety.rs

use crate::flog::FLOG;
use std::cell::{Ref, RefCell, RefMut};
use std::rc::{Rc, Weak};
use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::MutexGuard;

#[derive(Debug, Default)]
pub struct RelaxedAtomicBool(AtomicBool);

impl RelaxedAtomicBool {
    pub const fn new(value: bool) -> Self {
        Self(AtomicBool::new(value))
    }
    pub fn load(&self) -> bool {
        self.0.load(Ordering::Relaxed)
    }
    pub fn store(&self, value: bool) {
        self.0.store(value, Ordering::Relaxed)
    }
    pub fn swap(&self, value: bool) -> bool {
        self.0.swap(value, Ordering::Relaxed)
    }
}

impl Clone for RelaxedAtomicBool {
    fn clone(&self) -> Self {
        Self(AtomicBool::new(self.load()))
    }
}

pub struct SharedFromThisBase<T> {
    weak: RefCell<Weak<T>>,
}

impl<T> SharedFromThisBase<T> {
    pub fn new() -> SharedFromThisBase<T> {
        SharedFromThisBase {
            weak: RefCell::new(Weak::new()),
        }
    }

    pub fn initialize(&self, r: &Rc<T>) {
        *self.weak.borrow_mut() = Rc::downgrade(r);
    }
}

pub trait SharedFromThis<T> {
    fn get_base(&self) -> &SharedFromThisBase<T>;

    fn shared_from_this(&self) -> Rc<T> {
        self.get_base().weak.borrow().upgrade().unwrap()
    }
}

pub struct DebugRef<'a, T>(Ref<'a, T>);

impl<'a, T> DebugRef<'a, T> {
    pub fn new(r: Ref<'a, T>) -> Self {
        FLOG!(
            refcell,
            "CREATE DebugRef",
            std::backtrace::Backtrace::capture()
        );
        Self(r)
    }
}

impl<'a, T> Drop for DebugRef<'a, T> {
    fn drop(&mut self) {
        FLOG!(
            refcell,
            "DROP DebugRef",
            std::backtrace::Backtrace::capture()
        );
    }
}

impl<'a, T> std::ops::Deref for DebugRef<'a, T> {
    type Target = T;
    fn deref(&self) -> &Self::Target {
        &self.0
    }
}

pub struct DebugRefMut<'a, T>(RefMut<'a, T>);

impl<'a, T> DebugRefMut<'a, T> {
    pub fn new(r: RefMut<'a, T>) -> Self {
        FLOG!(
            refcell,
            "CREATE DebugRefMut",
            std::backtrace::Backtrace::capture()
        );
        Self(r)
    }
}

impl<'a, T> Drop for DebugRefMut<'a, T> {
    fn drop(&mut self) {
        FLOG!(
            refcell,
            "DROP DebugRefMut",
            std::backtrace::Backtrace::capture()
        );
    }
}
impl<'a, T> std::ops::Deref for DebugRefMut<'a, T> {
    type Target = T;
    fn deref(&self) -> &Self::Target {
        &self.0
    }
}

impl<'a, T> std::ops::DerefMut for DebugRefMut<'a, T> {
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.0
    }
}

pub struct DebugMutexGuard<'a, T>(MutexGuard<'a, T>);

impl<'a, T> DebugMutexGuard<'a, T> {
    pub fn new(r: MutexGuard<'a, T>) -> Self {
        FLOG!(
            refcell,
            "CREATE DebugMutexGuard",
            std::backtrace::Backtrace::capture()
        );
        Self(r)
    }
}

impl<'a, T> Drop for DebugMutexGuard<'a, T> {
    fn drop(&mut self) {
        FLOG!(
            refcell,
            "DROP DebugMutexGuard",
            std::backtrace::Backtrace::capture()
        );
    }
}

impl<'a, T> std::ops::Deref for DebugMutexGuard<'a, T> {
    type Target = T;
    fn deref(&self) -> &Self::Target {
        &self.0
    }
}
impl<'a, T> std::ops::DerefMut for DebugMutexGuard<'a, T> {
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.0
    }
}