Struct CuHandle 

pub struct CuHandle<T: Debug + Send + Sync>(/* private fields */);

A shareable handle to a pooled or detached object.

When T: ArrayLike, the handle also participates in Copper’s buffer pool APIs.

Implementations

impl<T: Debug + Send + Sync> CuHandle<T>

pub fn new_detached(inner: T) -> Self

Create a new CuHandle not part of a Pool (not for onboard usages, use pools instead)

pub fn new_detached_box(inner: Box<T>) -> Self

Create a detached handle from an already heap-allocated object.

pub fn new_detached_with_mode(inner: T, mode: HandleContent) -> Self

Create a detached handle with a non-default logging mode.

Mostly useful for tests and for sources that want to mint detached handles (instead of pool-acquired ones) under a specific HandleContent policy.

pub fn with_inner<R>(&self, f: impl FnOnce(&CuHandleInner<T>) -> R) -> R

Safely access the inner value, applying a closure to it.

pub fn with_inner_mut<R>(&self, f: impl FnOnce(&mut CuHandleInner<T>) -> R) -> R

Mutably access the inner value, applying a closure to it.

pub fn strong_count(&self) -> usize

Returns the number of handles sharing this payload storage.

pub fn is_unique(&self) -> bool

Returns true when this is the only handle to this payload storage.

pub fn mark_touched(&self)

Mark this handle as read by a downstream consumer.

When the source is configured with HandleContent::TouchedOnly, the unified-log encoder will only write the payload bytes if at least one consumer called this. Cheap (one relaxed atomic store); safe to call multiple times.

pub fn was_touched(&self) -> bool

Returns true if mark_touched has ever been called on this handle (or any clone of it).

pub fn logging_mode(&self) -> HandleContent

Logging mode currently in effect for this handle.

pub fn with_touched_inner<R>(&self, f: impl FnOnce(&CuHandleInner<T>) -> R) -> R

Convenience: with_inner plus mark_touched in one call, for the common consumer-side access pattern.

pub fn payload_should_log(&self) -> bool

Decides whether the unified-log encoder should write this handle’s payload bytes for the current frame.

This is the inherent “specific” arm of the autoref-specialization pattern; the encoder resolves to this method for handle payloads (or composite payloads that forward to it) and to PayloadDefaultLoggingPolicy::payload_should_log for every other payload type.

pub fn apply_handle_content_policy(&self, mode: HandleContent)

Apply a source’s configured HandleContent policy to this handle. Inherent “specific” arm of the autoref-specialization pattern; visible to every clone. Relaxed is sufficient — synchronization piggy-backs on the copperlist handoff.

Methods from Deref<Target = Mutex<CuHandleInner<T>>>

pub fn get_cloned(&self) -> Result<T, PoisonError<()>>

where T: Clone,

🔬This is a nightly-only experimental API. (lock_value_accessors)

Returns the contained value by cloning it.

Errors

If another user of this mutex panicked while holding the mutex, then this call will return an error instead.

Examples

#![feature(lock_value_accessors)]

use std::sync::Mutex;

let mut mutex = Mutex::new(7);

assert_eq!(mutex.get_cloned().unwrap(), 7);

pub fn set(&self, value: T) -> Result<(), PoisonError<T>>

🔬This is a nightly-only experimental API. (lock_value_accessors)

Sets the contained value.

Errors

If another user of this mutex panicked while holding the mutex, then this call will return an error containing the provided value instead.

Examples

#![feature(lock_value_accessors)]

use std::sync::Mutex;

let mut mutex = Mutex::new(7);

assert_eq!(mutex.get_cloned().unwrap(), 7);
mutex.set(11).unwrap();
assert_eq!(mutex.get_cloned().unwrap(), 11);

pub fn replace(&self, value: T) -> Result<T, PoisonError<T>>

🔬This is a nightly-only experimental API. (lock_value_accessors)

Replaces the contained value with value, and returns the old contained value.

Errors

If another user of this mutex panicked while holding the mutex, then this call will return an error containing the provided value instead.

Examples

#![feature(lock_value_accessors)]

use std::sync::Mutex;

let mut mutex = Mutex::new(7);

assert_eq!(mutex.replace(11).unwrap(), 7);
assert_eq!(mutex.get_cloned().unwrap(), 11);

pub fn lock(&self) -> Result<MutexGuard<'_, T>, PoisonError<MutexGuard<'_, T>>>

Acquires a mutex, blocking the current thread until it is able to do so.

This function will block the local thread until it is available to acquire the mutex. Upon returning, the thread is the only thread with the lock held. An RAII guard is returned to allow scoped unlock of the lock. When the guard goes out of scope, the mutex will be unlocked.

The exact behavior on locking a mutex in the thread which already holds the lock is left unspecified. However, this function will not return on the second call (it might panic or deadlock, for example).

Errors

If another user of this mutex panicked while holding the mutex, then this call will return an error once the mutex is acquired. The acquired mutex guard will be contained in the returned error.

Panics

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

Examples

use std::sync::{Arc, Mutex};
use std::thread;

let mutex = Arc::new(Mutex::new(0));
let c_mutex = Arc::clone(&mutex);

thread::spawn(move || {
    *c_mutex.lock().unwrap() = 10;
}).join().expect("thread::spawn failed");
assert_eq!(*mutex.lock().unwrap(), 10);

pub fn try_lock( &self, ) -> Result<MutexGuard<'_, T>, TryLockError<MutexGuard<'_, T>>>

Attempts to acquire this lock.

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

This function does not block.

Errors

If another user of this mutex panicked while holding the mutex, then this call will return the Poisoned error if the mutex would otherwise be acquired. An acquired lock guard will be contained in the returned error.

If the mutex could not be acquired because it is already locked, then this call will return the WouldBlock error.

Examples

use std::sync::{Arc, Mutex};
use std::thread;

let mutex = Arc::new(Mutex::new(0));
let c_mutex = Arc::clone(&mutex);

thread::spawn(move || {
    let mut lock = c_mutex.try_lock();
    if let Ok(ref mut mutex) = lock {
        **mutex = 10;
    } else {
        println!("try_lock failed");
    }
}).join().expect("thread::spawn failed");
assert_eq!(*mutex.lock().unwrap(), 10);

pub fn is_poisoned(&self) -> bool

Determines whether the mutex is poisoned.

If another thread is active, the mutex 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, Mutex};
use std::thread;

let mutex = Arc::new(Mutex::new(0));
let c_mutex = Arc::clone(&mutex);

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

pub fn clear_poison(&self)

Clear the poisoned state from a mutex.

If the mutex 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 mutex 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, Mutex};
use std::thread;

let mutex = Arc::new(Mutex::new(0));
let c_mutex = Arc::clone(&mutex);

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

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

pub fn data_ptr(&self) -> *mut T

🔬This is a nightly-only experimental API. (mutex_data_ptr)

Returns a raw pointer to the underlying data.

The returned pointer is always non-null and properly aligned, but it is the user’s responsibility to ensure that any reads and writes through it are properly synchronized to avoid data races, and that it is not read or written through after the mutex is dropped.

Trait Implementations

impl<T: Debug + Send + Sync> Clone for CuHandle<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug + Debug + Send + Sync> Debug for CuHandle<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<U: ElementType + Decode<()> + 'static> Decode<()> for CuHandle<Vec<U>>

fn decode<D: Decoder<Context = ()>>( decoder: &mut D, ) -> Result<Self, DecodeError>

Attempt to decode this type with the given Decode.

impl<U: ElementType + Decode<()> + 'static> Decode<()> for CuHandle<CuSharedMemoryBuffer<U>>

fn decode<D: Decoder<Context = ()>>( decoder: &mut D, ) -> Result<Self, DecodeError>

Attempt to decode this type with the given Decode.

impl<T: Debug + Send + Sync> Default for CuHandle<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T: Debug + Send + Sync> Deref for CuHandle<T>

type Target = Mutex<CuHandleInner<T>>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<'de, U> Deserialize<'de> for CuHandle<Vec<U>>

where U: ElementType + Deserialize<'de> + 'static,

fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error>

Deserialize this value from the given Serde deserializer.

impl<'de, U> Deserialize<'de> for CuHandle<CuSharedMemoryBuffer<U>>

where U: ElementType + Deserialize<'de> + 'static,

fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error>

Deserialize this value from the given Serde deserializer.

impl<T: ArrayLike + Encode> Encode for CuHandle<T>

where <T as ArrayLike>::Element: 'static,

fn encode<E: Encoder>(&self, encoder: &mut E) -> Result<(), EncodeError>

Encode a given type.

impl<T: Debug + Send + Sync> HandleContentAware for CuHandle<T>

impl<U> Serialize for CuHandle<Vec<U>>

where U: ElementType + Serialize + 'static,

fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error>

Serialize this value into the given Serde serializer.

impl<U> Serialize for CuHandle<CuSharedMemoryBuffer<U>>

where U: ElementType + Serialize + 'static,

fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error>

Serialize this value into the given Serde serializer.