Remove Mutex::into_lock

This commit is contained in:
Pierre Krieger 2018-01-05 11:58:27 +01:00
parent b83ebe3c88
commit c2d4b75988
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@ -3,45 +3,6 @@
//! API is similar to [`futures::sync::BiLock`](https://docs.rs/futures/0.1.11/futures/sync/struct.BiLock.html)
//! However, it can be cloned into as many handles as desired.
//!
//! ```
//! extern crate futures;
//! extern crate futures_mutex;
//!
//! use futures::{Future, Poll, Async};
//! use futures_mutex::Mutex;
//!
//! struct AddTwo {
//! lock: Mutex<usize>
//! }
//!
//! impl Future for AddTwo {
//! type Item = usize;
//! type Error = ();
//! fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
//! match self.lock.poll_lock() {
//! Async::Ready(mut g) => {
//! *g += 2;
//! Ok(Async::Ready(*g))
//! },
//! Async::NotReady => Ok(Async::NotReady)
//! }
//! }
//! }
//!
//! fn main() {
//! let lock1: Mutex<usize> = Mutex::new(0);
//! let lock2 = lock1.clone();
//!
//! let future = AddTwo { lock: lock2 };
//!
//! // This future will return the current value and the recovered lock.
//! let used_lock = lock1.into_lock().map(|b| (*b, b.unlock()));
//!
//! let _ = future.join(used_lock).map(|(add_two, (value, _))| {
//! assert_eq!(add_two, value);
//! }).wait().unwrap();
//! }
//! ```
extern crate futures;
extern crate crossbeam;
@ -131,17 +92,6 @@ impl<T> Mutex<T> {
}
}
/// Convert this lock into a future that resolves to a guard that allows access to the data.
/// This function returns `MutexAcquire<T>`, which resolves to a `MutexGuard<T>`
/// guard type.
///
/// The returned future will never return an error.
pub fn into_lock(self) -> MutexIntoAcquire<T> {
MutexIntoAcquire {
inner: self
}
}
/// We unlock the mutex and wait for someone to lock. We try and unpark as many tasks as we
/// can to prevents dead tasks from deadlocking the mutex, or tasks that have finished their
/// critical section and were awakened.
@ -211,66 +161,6 @@ impl<'a, T> Future for MutexAcquire<'a, T> {
}
}
/// Future returned by `FutMutex::lock` which resolves to a guard when a lock is acquired.
#[derive(Debug)]
pub struct MutexIntoAcquire<T> {
inner: Mutex<T>
}
impl<T> Future for MutexIntoAcquire<T> {
type Item = MutexAcquired<T>;
type Error = ();
fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
match self.inner.poll_lock() {
Async::Ready(r) => {
mem::forget(r);
Ok(MutexAcquired {
inner: Mutex{ inner: self.inner.inner.clone() }
}.into())
},
Async::NotReady => Ok(Async::NotReady)
}
}
}
#[derive(Debug)]
/// Resolved value of `FutMutexAcquire<T>` future
///
/// This value works like `FutMutexGuard<T>`, providing a RAII guard to the value `T` through
/// `Deref` and `DerefMut`. Will unlock the lock when dropped; the original `FutMutex` can be
/// recovered with `unlock()`.
pub struct MutexAcquired<T> {
inner: Mutex<T>
}
impl<T> MutexAcquired<T> {
pub fn unlock(self) -> Mutex<T> {
Mutex {
inner: self.inner.inner.clone()
}
}
}
impl<T> Deref for MutexAcquired<T> {
type Target = T;
fn deref(&self) -> &Self::Target {
unsafe { &*self.inner.inner.data.get() }
}
}
impl<T> DerefMut for MutexAcquired<T> {
fn deref_mut(&mut self) -> &mut T {
unsafe { &mut *self.inner.inner.data.get() }
}
}
impl<T> Drop for MutexAcquired<T> {
fn drop(&mut self) {
self.inner.unlock();
}
}
#[cfg(test)]
mod tests {
use super::*;
@ -337,12 +227,7 @@ mod tests {
a: Some(lock1),
remaining: N,
};
let b = stream::iter_ok::<_, ()>(0..N).fold(lock2, |b, _n| {
b.into_lock().map(|mut b| {
*b += 1;
b.unlock()
})
});
let b = a.clone();
let t1 = thread::spawn(move || a.wait());
let b = b.wait().expect("b error");
@ -357,6 +242,7 @@ mod tests {
Async::NotReady => panic!("poll not ready"),
}
#[derive(Clone)]
struct Increment {
remaining: usize,
a: Option<Mutex<usize>>,