struct RES {
    __private_field: (),
}

Fields§

§__private_field: ()

Methods from Deref<Target = RwLock<Option<Box<dyn ResourceReaderMethods + Sync + Send>>>>§

1.0.0 · source

pub fn read( &self ) -> Result<RwLockReadGuard<'_, T>, PoisonError<RwLockReadGuard<'_, T>>>

Locks this RwLock with shared read access, blocking the current thread until it can be acquired.

The calling thread will be blocked until there are no more writers which hold the lock. There may be other readers currently inside the lock when this method returns. This method does not provide any guarantees with respect to the ordering of whether contentious readers or writers will acquire the lock first.

Returns an RAII guard which will release this thread’s shared access once it is dropped.

§Errors

This function will return an error if the RwLock is poisoned. An RwLock is poisoned whenever a writer panics while holding an exclusive lock. The failure will occur immediately after the lock has been acquired.

§Panics

This function might panic when called if the lock is already held by the current thread.

§Examples
use std::sync::{Arc, RwLock};
use std::thread;

let lock = Arc::new(RwLock::new(1));
let c_lock = Arc::clone(&lock);

let n = lock.read().unwrap();
assert_eq!(*n, 1);

thread::spawn(move || {
    let r = c_lock.read();
    assert!(r.is_ok());
}).join().unwrap();
1.0.0 · source

pub fn try_read( &self ) -> Result<RwLockReadGuard<'_, T>, TryLockError<RwLockReadGuard<'_, T>>>

Attempts to acquire this RwLock with shared read access.

If the access could not be granted at this time, then Err is returned. Otherwise, an RAII guard is returned which will release the shared access when it is dropped.

This function does not block.

This function does not provide any guarantees with respect to the ordering of whether contentious readers or writers will acquire the lock first.

§Errors

This function will return the Poisoned error if the RwLock is poisoned. An RwLock is poisoned whenever a writer panics while holding an exclusive lock. Poisoned will only be returned if the lock would have otherwise been acquired.

This function will return the WouldBlock error if the RwLock could not be acquired because it was already locked exclusively.

§Examples
use std::sync::RwLock;

let lock = RwLock::new(1);

match lock.try_read() {
    Ok(n) => assert_eq!(*n, 1),
    Err(_) => unreachable!(),
};
1.0.0 · source

pub fn write( &self ) -> Result<RwLockWriteGuard<'_, T>, PoisonError<RwLockWriteGuard<'_, T>>>

Locks this RwLock with exclusive write access, blocking the current thread until it can be acquired.

This function will not return while other writers or other readers currently have access to the lock.

Returns an RAII guard which will drop the write access of this RwLock when dropped.

§Errors

This function will return an error if the RwLock is poisoned. An RwLock is poisoned whenever a writer panics while holding an exclusive lock. An error will be returned when the lock is acquired.

§Panics

This function might panic when called if the lock is already held by the current thread.

§Examples
use std::sync::RwLock;

let lock = RwLock::new(1);

let mut n = lock.write().unwrap();
*n = 2;

assert!(lock.try_read().is_err());
1.0.0 · source

pub fn try_write( &self ) -> Result<RwLockWriteGuard<'_, T>, TryLockError<RwLockWriteGuard<'_, T>>>

Attempts to lock this RwLock with exclusive write access.

If the lock could not be acquired at this time, then Err is returned. Otherwise, an RAII guard is returned which will release the lock when it is dropped.

This function does not block.

This function does not provide any guarantees with respect to the ordering of whether contentious readers or writers will acquire the lock first.

§Errors

This function will return the Poisoned error if the RwLock is poisoned. An RwLock is poisoned whenever a writer panics while holding an exclusive lock. Poisoned will only be returned if the lock would have otherwise been acquired.

This function will return the WouldBlock error if the RwLock could not be acquired because it was already locked exclusively.

§Examples
use std::sync::RwLock;

let lock = RwLock::new(1);

let n = lock.read().unwrap();
assert_eq!(*n, 1);

assert!(lock.try_write().is_err());
1.2.0 · source

pub fn is_poisoned(&self) -> bool

Determines whether the lock is poisoned.

If another thread is active, the lock can still become poisoned at any time. You should not trust a false value for program correctness without additional synchronization.

§Examples
use std::sync::{Arc, RwLock};
use std::thread;

let lock = Arc::new(RwLock::new(0));
let c_lock = Arc::clone(&lock);

let _ = thread::spawn(move || {
    let _lock = c_lock.write().unwrap();
    panic!(); // the lock gets poisoned
}).join();
assert_eq!(lock.is_poisoned(), true);
1.77.0 · source

pub fn clear_poison(&self)

Clear the poisoned state from a lock

If the lock is poisoned, it will remain poisoned until this function is called. This allows recovering from a poisoned state and marking that it has recovered. For example, if the value is overwritten by a known-good value, then the lock can be marked as un-poisoned. Or possibly, the value could be inspected to determine if it is in a consistent state, and if so the poison is removed.

§Examples
use std::sync::{Arc, RwLock};
use std::thread;

let lock = Arc::new(RwLock::new(0));
let c_lock = Arc::clone(&lock);

let _ = thread::spawn(move || {
    let _lock = c_lock.write().unwrap();
    panic!(); // the lock gets poisoned
}).join();

assert_eq!(lock.is_poisoned(), true);
let guard = lock.write().unwrap_or_else(|mut e| {
    **e.get_mut() = 1;
    lock.clear_poison();
    e.into_inner()
});
assert_eq!(lock.is_poisoned(), false);
assert_eq!(*guard, 1);

Trait Implementations§

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impl Deref for RES

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type Target = RwLock<Option<Box<dyn ResourceReaderMethods + Send + Sync>>>

The resulting type after dereferencing.
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fn deref(&self) -> &RwLock<Option<Box<dyn ResourceReaderMethods + Sync + Send>>>

Dereferences the value.
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impl LazyStatic for RES

Auto Trait Implementations§

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impl Freeze for RES

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impl RefUnwindSafe for RES

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impl Send for RES

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impl Sync for RES

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impl Unpin for RES

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impl UnwindSafe for RES

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> Same for T

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type Output = T

Should always be Self
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
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impl<V, T> VZip<V> for T
where V: MultiLane<T>,

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fn vzip(self) -> V

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impl<T> ErasedDestructor for T
where T: 'static,

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impl<T> MaybeSendSync for T