greenie 0.4.0

Green threads and coroutines in stable Rust
Documentation 
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pub mod barrier;
pub mod channel;
pub mod condvar;
pub mod mutex;

pub use channel::Channel;
pub use condvar::Condvar;

///A mutual exclusion primitive useful for protecting shared data
///
/// This mutex will block threads waiting for the lock to become available. The mutex can also be statically initialized or created via a
/// new constructor. Each mutex has a type parameter which represents the data that it is protecting. The data can only be accessed
/// through the RAII guards returned from lock and try_lock, which guarantees that the data is only ever accessed when the mutex
/// is locked.
pub struct Mutex<T> {
    value: crate::ptr::Ptr<T>,
    pub mutex: mutex::Mutex,
}

impl<T> Clone for Mutex<T> {
    fn clone(&self) -> Self {
        Self {
            value: self.value,
            mutex: self.mutex.clone(),
        }
    }
}

impl<T> Mutex<T> {
    /// Creates a new mutex in an unlocked state ready for use.
    pub fn new(value: T) -> Self {
        Self {
            value: crate::ptr::Ptr::new(value),
            mutex: mutex::Mutex::new(),
        }
    }
    /// 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.
    ///
    /// ## Panics
    /// Panics if deadlock found
    pub fn lock(&self) -> MutexGuard<'_, T> {
        self.mutex.lock();
        MutexGuard {
            mtx: self.mutex.clone(),
            value: self.value.get(),
        }
    }
    /// Attempts to acquire this lock.
    /// If the lock could not be acquired at this time, then `None` is returned. Otherwise, RAII guard returned is returned.
    /// This function does not block.
    pub fn try_lock(&self) -> Option<MutexGuard<'_, T>> {
        if self.mutex.try_lock() {
            Some(MutexGuard {
                mtx: self.mutex.clone(),
                value: self.value.get(),
            })
        } else {
            None
        }
    }
}

pub struct MutexGuard<'a, T> {
    value: &'a mut T,
    mtx: mutex::Mutex,
}

impl<T> Drop for MutexGuard<'_, T> {
    fn drop(&mut self) {
        self.mtx.unlock();
    }
}

use std::ops::{Deref, DerefMut};

impl<T> Deref for MutexGuard<'_, T> {
    type Target = T;
    fn deref(&self) -> &T {
        self.value
    }
}

impl<T> DerefMut for MutexGuard<'_, T> {
    fn deref_mut(&mut self) -> &mut T {
        self.value
    }
}