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//! A minimal adaption of the `parking_lot` synchronization primitives to the
//! equivalent `std::sync` types.
//!
//! This can be extended to additional types/methods as required.
use std::fmt;
use std::marker::PhantomData;
use std::ops::{Deref, DerefMut};
use std::sync::LockResult;
use std::time::Duration;
// All types in this file are marked with PhantomData to ensure that
// parking_lot's send_guard feature does not leak through and affect when Tokio
// types are Send.
//
// Types that do not need wrapping
pub(crate) use parking_lot::WaitTimeoutResult;
#[derive(Debug)]
pub(crate) struct Mutex<T: ?Sized>(PhantomData<std::sync::Mutex<T>>, parking_lot::Mutex<T>);
#[derive(Debug)]
pub(crate) struct RwLock<T>(PhantomData<std::sync::RwLock<T>>, parking_lot::RwLock<T>);
#[derive(Debug)]
pub(crate) struct Condvar(PhantomData<std::sync::Condvar>, parking_lot::Condvar);
#[derive(Debug)]
pub(crate) struct MutexGuard<'a, T: ?Sized>(
PhantomData<std::sync::MutexGuard<'a, T>>,
parking_lot::MutexGuard<'a, T>,
);
#[derive(Debug)]
pub(crate) struct RwLockReadGuard<'a, T: ?Sized>(
PhantomData<std::sync::RwLockReadGuard<'a, T>>,
parking_lot::RwLockReadGuard<'a, T>,
);
#[derive(Debug)]
pub(crate) struct RwLockWriteGuard<'a, T: ?Sized>(
PhantomData<std::sync::RwLockWriteGuard<'a, T>>,
parking_lot::RwLockWriteGuard<'a, T>,
);
impl<T> Mutex<T> {
#[inline]
pub(crate) fn new(t: T) -> Mutex<T> {
Mutex(PhantomData, parking_lot::Mutex::new(t))
}
#[inline]
#[cfg(not(all(loom, test)))]
pub(crate) const fn const_new(t: T) -> Mutex<T> {
Mutex(PhantomData, parking_lot::const_mutex(t))
}
#[inline]
pub(crate) fn lock(&self) -> MutexGuard<'_, T> {
MutexGuard(PhantomData, self.1.lock())
}
#[inline]
pub(crate) fn try_lock(&self) -> Option<MutexGuard<'_, T>> {
self.1
.try_lock()
.map(|guard| MutexGuard(PhantomData, guard))
}
#[inline]
pub(crate) fn get_mut(&mut self) -> &mut T {
self.1.get_mut()
}
// Note: Additional methods `is_poisoned` and `into_inner`, can be
// provided here as needed.
}
impl<'a, T: ?Sized> Deref for MutexGuard<'a, T> {
type Target = T;
fn deref(&self) -> &T {
self.1.deref()
}
}
impl<'a, T: ?Sized> DerefMut for MutexGuard<'a, T> {
fn deref_mut(&mut self) -> &mut T {
self.1.deref_mut()
}
}
impl<T> RwLock<T> {
pub(crate) fn new(t: T) -> RwLock<T> {
RwLock(PhantomData, parking_lot::RwLock::new(t))
}
pub(crate) fn read(&self) -> LockResult<RwLockReadGuard<'_, T>> {
Ok(RwLockReadGuard(PhantomData, self.1.read()))
}
pub(crate) fn write(&self) -> LockResult<RwLockWriteGuard<'_, T>> {
Ok(RwLockWriteGuard(PhantomData, self.1.write()))
}
}
impl<'a, T: ?Sized> Deref for RwLockReadGuard<'a, T> {
type Target = T;
fn deref(&self) -> &T {
self.1.deref()
}
}
impl<'a, T: ?Sized> Deref for RwLockWriteGuard<'a, T> {
type Target = T;
fn deref(&self) -> &T {
self.1.deref()
}
}
impl<'a, T: ?Sized> DerefMut for RwLockWriteGuard<'a, T> {
fn deref_mut(&mut self) -> &mut T {
self.1.deref_mut()
}
}
impl Condvar {
#[inline]
pub(crate) fn new() -> Condvar {
Condvar(PhantomData, parking_lot::Condvar::new())
}
#[inline]
pub(crate) fn notify_one(&self) {
self.1.notify_one();
}
#[inline]
pub(crate) fn notify_all(&self) {
self.1.notify_all();
}
#[inline]
pub(crate) fn wait<'a, T>(
&self,
mut guard: MutexGuard<'a, T>,
) -> LockResult<MutexGuard<'a, T>> {
self.1.wait(&mut guard.1);
Ok(guard)
}
#[inline]
pub(crate) fn wait_timeout<'a, T>(
&self,
mut guard: MutexGuard<'a, T>,
timeout: Duration,
) -> LockResult<(MutexGuard<'a, T>, WaitTimeoutResult)> {
let wtr = self.1.wait_for(&mut guard.1, timeout);
Ok((guard, wtr))
}
// Note: Additional methods `wait_timeout_ms`, `wait_timeout_until`,
// `wait_until` can be provided here as needed.
}
impl<'a, T: ?Sized + fmt::Display> fmt::Display for MutexGuard<'a, T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt::Display::fmt(&self.1, f)
}
}
impl<'a, T: ?Sized + fmt::Display> fmt::Display for RwLockReadGuard<'a, T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt::Display::fmt(&self.1, f)
}
}
impl<'a, T: ?Sized + fmt::Display> fmt::Display for RwLockWriteGuard<'a, T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt::Display::fmt(&self.1, f)
}
}