Struct ArcStdMutex 

pub struct ArcStdMutex<T> { /* private fields */ }

Synchronous Standard Mutex Wrapper

Provides an encapsulation of synchronous mutex using std::sync::Mutex for protecting shared data in synchronous environments. Supports safe access and modification of shared data across multiple threads.

Features

• Synchronously acquires locks, may block threads
• Supports trying to acquire locks (non-blocking)
• Thread-safe, supports multi-threaded sharing
• Automatic lock management through RAII ensures proper lock release
• Implements Deref and AsRef to expose the underlying std::sync::Mutex API when guard-based access is needed

Usage Example

use qubit_lock::lock::{ArcStdMutex, Lock};

let counter = ArcStdMutex::new(0);

// Synchronously modify data
counter.write(|c| {
    *c += 1;
    println!("Counter: {}", *c);
});

// Try to acquire lock
if let Ok(value) = counter.try_read(|c| *c) {
    println!("Current value: {}", value);
}

Implementations

impl<T> ArcStdMutex<T>

pub fn new(data: T) -> Self

Creates a new synchronous mutex lock

Arguments

• data - The data to be protected

Returns

Returns a new ArcStdMutex instance

Example

use qubit_lock::lock::ArcStdMutex;

let lock = ArcStdMutex::new(42);

Methods from Deref<Target = Mutex<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> AsRef<Mutex<T>> for ArcStdMutex<T>

fn as_ref(&self) -> &Mutex<T>

Returns a reference to the underlying standard mutex.

This is useful when callers need guard-based APIs such as Mutex::lock or Mutex::try_lock instead of the closure-based Lock methods.

impl<T> Clone for ArcStdMutex<T>

fn clone(&self) -> Self

Clones the synchronous mutex

Creates a new ArcStdMutex instance that shares the same underlying lock with the original instance. This allows multiple threads to hold references to the same lock simultaneously.

Returns

A new handle sharing the same underlying mutex and protected value.

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

Performs copy-assignment from source.

impl<T> Deref for ArcStdMutex<T>

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

Dereferences this wrapper to the underlying standard mutex.

Method-call dereferencing lets callers use native mutex APIs directly, while the wrapper continues to provide the Lock trait methods.

type Target = Mutex<T>

The resulting type after dereferencing.

impl<T> Lock<T> for ArcStdMutex<T>

fn read<R, F>(&self, f: F) -> R

where F: FnOnce(&T) -> R,

Acquires a read lock and executes an operation

For ArcStdMutex, this acquires the same exclusive lock as write operations, but provides immutable access to the data. This ensures thread safety while allowing read-only operations.

Arguments

• f - The closure to be executed while holding the read lock

Returns

Returns the result of executing the closure

Panics

Panics if the underlying standard mutex is poisoned.

Example

use qubit_lock::lock::{ArcStdMutex, Lock};

let counter = ArcStdMutex::new(42);

let value = counter.read(|c| *c);
println!("Current value: {}", value);

fn write<R, F>(&self, f: F) -> R

where F: FnOnce(&mut T) -> R,

Acquires a write lock and executes an operation

Synchronously acquires the exclusive lock, executes the provided closure with mutable access, and then automatically releases the lock. This is the recommended usage pattern for modifications.

Arguments

• f - The closure to be executed while holding the write lock

Returns

Returns the result of executing the closure

Panics

Panics if the underlying standard mutex is poisoned.

Example

use qubit_lock::lock::{ArcStdMutex, Lock};

let counter = ArcStdMutex::new(0);

let result = counter.write(|c| {
    *c += 1;
    *c
});

println!("Counter value: {}", result);

fn try_read<R, F>(&self, f: F) -> Result<R, TryLockError>

where F: FnOnce(&T) -> R,

Attempts to acquire a read lock without blocking

Attempts to immediately acquire the read lock. If the lock is unavailable, returns a detailed error. This is a non-blocking operation.

Arguments

• f - The closure to be executed while holding the read lock

Returns

• Ok(R) - If the lock was successfully acquired and the closure executed
• Err(TryLockError::WouldBlock) - If the lock is already held by another thread
• Err(TryLockError::Poisoned) - If the lock is poisoned

Example

use qubit_lock::lock::{ArcStdMutex, Lock};

let counter = ArcStdMutex::new(42);

if let Ok(value) = counter.try_read(|c| *c) {
    println!("Current value: {}", value);
} else {
    println!("Lock is unavailable");
}

fn try_write<R, F>(&self, f: F) -> Result<R, TryLockError>

where F: FnOnce(&mut T) -> R,

Attempts to acquire a write lock without blocking

Attempts to immediately acquire the write lock. If the lock is unavailable, returns a detailed error. This is a non-blocking operation.

Arguments

• f - The closure to be executed while holding the write lock

Returns

• Ok(R) - If the lock was successfully acquired and the closure executed
• Err(TryLockError::WouldBlock) - If the lock is already held by another thread
• Err(TryLockError::Poisoned) - If the lock is poisoned

Example

use qubit_lock::lock::{ArcStdMutex, Lock};

let counter = ArcStdMutex::new(0);

if let Ok(result) = counter.try_write(|c| {
    *c += 1;
    *c
}) {
    println!("New value: {}", result);
} else {
    println!("Lock is unavailable");
}