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use std::{
fmt,
marker::PhantomData,
ops::{Deref, DerefMut},
ptr::NonNull,
};
#[cfg(feature = "parking_lot")]
extern crate parking_lot;
extern crate stable_deref_trait;
use stable_deref_trait::{CloneStableDeref, StableDeref};
mod raw_rwlock;
use self::raw_rwlock::RawRwLock;
pub struct Cryo<'a, T: ?Sized + 'a> {
state: State<T>,
_phantom: PhantomData<&'a T>,
}
unsafe impl<'a, T: ?Sized + Send> Send for Cryo<'a, T> {}
unsafe impl<'a, T: ?Sized + Send + Sync> Sync for Cryo<'a, T> {}
pub struct CryoMut<'a, T: ?Sized + 'a> {
state: State<T>,
_phantom: PhantomData<&'a mut T>,
}
unsafe impl<'a, T: ?Sized + Send> Send for CryoMut<'a, T> {}
unsafe impl<'a, T: ?Sized + Send + Sync> Sync for CryoMut<'a, T> {}
struct State<T: ?Sized> {
data: NonNull<T>,
lock: RawRwLock,
}
pub type CryoRef<T> = CryoMutReadGuard<T>;
pub struct CryoMutReadGuard<T: ?Sized> {
state: NonNull<State<T>>,
}
unsafe impl<T: ?Sized + Send> Send for CryoMutReadGuard<T> {}
unsafe impl<T: ?Sized + Send + Sync> Sync for CryoMutReadGuard<T> {}
pub struct CryoMutWriteGuard<T: ?Sized> {
state: NonNull<State<T>>,
}
unsafe impl<T: ?Sized + Send> Send for CryoMutWriteGuard<T> {}
impl<'a, T: ?Sized + 'a> Cryo<'a, T> {
pub unsafe fn new(x: &'a T) -> Self {
Self {
state: State {
data: NonNull::from(x),
lock: RawRwLock::new(),
},
_phantom: PhantomData,
}
}
pub fn borrow(&self) -> CryoRef<T> {
self.state.lock.raw_read();
CryoRef {
state: NonNull::from(&self.state),
}
}
pub fn get(&self) -> &'a T {
unsafe { &*self.state.data.as_ptr() }
}
}
impl<'a, T: ?Sized + fmt::Debug> fmt::Debug for Cryo<'a, T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("Cryo").field("data", &self.get()).finish()
}
}
impl<'a, T: ?Sized + 'a> Drop for Cryo<'a, T> {
fn drop(&mut self) {
self.state.lock.raw_write();
}
}
impl<'a, T: ?Sized + 'a> CryoMut<'a, T> {
pub unsafe fn new(x: &'a mut T) -> Self {
Self {
state: State {
data: NonNull::from(x),
lock: RawRwLock::new(),
},
_phantom: PhantomData,
}
}
pub fn read(&self) -> CryoMutReadGuard<T> {
self.state.lock.raw_read();
CryoMutReadGuard {
state: NonNull::from(&self.state),
}
}
pub fn try_read(&self) -> Option<CryoMutReadGuard<T>> {
if self.state.lock.raw_try_read() {
Some(CryoMutReadGuard {
state: NonNull::from(&self.state),
})
} else {
None
}
}
pub fn write(&self) -> CryoMutWriteGuard<T> {
self.state.lock.raw_write();
CryoMutWriteGuard {
state: NonNull::from(&self.state),
}
}
pub fn try_write(&self) -> Option<CryoMutWriteGuard<T>> {
if self.state.lock.raw_try_write() {
Some(CryoMutWriteGuard {
state: NonNull::from(&self.state),
})
} else {
None
}
}
pub fn try_get_mut(&mut self) -> Option<&mut T> {
if self.state.lock.raw_try_write() {
unsafe {
self.state.lock.raw_unlock_write();
}
Some(unsafe { self.state.data.as_mut() })
} else {
None
}
}
}
impl<'a, T: ?Sized + fmt::Debug> fmt::Debug for CryoMut<'a, T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
if let Some(x) = self.try_read() {
f.debug_struct("CryoMut").field("data", &&*x).finish()
} else {
struct LockedPlaceholder;
impl fmt::Debug for LockedPlaceholder {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.write_str("<locked>")
}
}
f.debug_struct("CryoMut")
.field("data", &LockedPlaceholder)
.finish()
}
}
}
impl<'a, T: ?Sized + 'a> Drop for CryoMut<'a, T> {
fn drop(&mut self) {
self.state.lock.raw_write();
}
}
impl<T: ?Sized> CryoMutReadGuard<T> {
unsafe fn state(&self) -> &State<T> {
self.state.as_ref()
}
}
impl<T: ?Sized> Deref for CryoMutReadGuard<T> {
type Target = T;
fn deref(&self) -> &Self::Target {
unsafe { self.state().data.as_ref() }
}
}
unsafe impl<T: ?Sized> StableDeref for CryoMutReadGuard<T> {}
unsafe impl<T: ?Sized> CloneStableDeref for CryoMutReadGuard<T> {}
impl<T: ?Sized> Clone for CryoMutReadGuard<T> {
fn clone(&self) -> Self {
unsafe {
self.state().lock.raw_read();
}
Self { state: self.state }
}
}
impl<T: ?Sized + fmt::Debug> fmt::Debug for CryoMutReadGuard<T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("CryoMutReadGuard")
.field("data", &&**self)
.finish()
}
}
impl<T: ?Sized> Drop for CryoMutReadGuard<T> {
fn drop(&mut self) {
unsafe {
self.state().lock.raw_unlock_read();
}
}
}
impl<T: ?Sized> CryoMutWriteGuard<T> {
unsafe fn state(&self) -> &State<T> {
self.state.as_ref()
}
}
impl<T: ?Sized> Deref for CryoMutWriteGuard<T> {
type Target = T;
fn deref(&self) -> &Self::Target {
unsafe { self.state().data.as_ref() }
}
}
impl<T: ?Sized> DerefMut for CryoMutWriteGuard<T> {
fn deref_mut(&mut self) -> &mut Self::Target {
unsafe { &mut *self.state().data.as_ptr() }
}
}
unsafe impl<T: ?Sized> StableDeref for CryoMutWriteGuard<T> {}
impl<T: ?Sized + fmt::Debug> fmt::Debug for CryoMutWriteGuard<T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("CryoMutWriteGuard")
.field("data", &&**self)
.finish()
}
}
impl<T: ?Sized> Drop for CryoMutWriteGuard<T> {
fn drop(&mut self) {
unsafe {
self.state().lock.raw_unlock_write();
}
}
}
pub fn with_cryo<T, R>(x: &T, f: impl FnOnce(&Cryo<T>) -> R) -> R {
f(&unsafe { Cryo::new(x) })
}
pub fn with_cryo_mut<T, R>(x: &mut T, f: impl FnOnce(&CryoMut<T>) -> R) -> R {
f(&unsafe { CryoMut::new(x) })
}