diff options
Diffstat (limited to 'src/collection/collection.rs')
| -rw-r--r-- | src/collection/collection.rs | 244 |
1 files changed, 0 insertions, 244 deletions
diff --git a/src/collection/collection.rs b/src/collection/collection.rs deleted file mode 100644 index a8d25a5..0000000 --- a/src/collection/collection.rs +++ /dev/null @@ -1,244 +0,0 @@ -use std::marker::PhantomData; - -use crate::{key::Keyable, lockable::Lock, Lockable, OwnedLockable}; - -use super::{LockGuard, RefLockCollection}; - -fn get_locks<'a, L: Lockable<'a> + 'a>(data: &'a L) -> Vec<&'a dyn Lock> { - let mut locks = Vec::new(); - data.get_ptrs(&mut locks); - locks.sort_by_key(|lock| std::ptr::from_ref(*lock)); - locks -} - -/// returns `true` if the sorted list contains a duplicate -#[must_use] -fn contains_duplicates(l: &[&dyn Lock]) -> bool { - l.windows(2).any(|window| { - std::ptr::addr_eq(std::ptr::from_ref(window[0]), std::ptr::from_ref(window[1])) - }) -} - -impl<'a, L: Lockable<'a>> AsRef<L> for RefLockCollection<'a, L> { - fn as_ref(&self) -> &L { - self.data - } -} - -impl<'a, L: Lockable<'a>> AsRef<Self> for RefLockCollection<'a, L> { - fn as_ref(&self) -> &Self { - self - } -} - -impl<'a, L: Lockable<'a>> AsMut<Self> for RefLockCollection<'a, L> { - fn as_mut(&mut self) -> &mut Self { - self - } -} - -impl<'a, L> IntoIterator for &'a RefLockCollection<'a, L> -where - &'a L: IntoIterator, -{ - type Item = <&'a L as IntoIterator>::Item; - type IntoIter = <&'a L as IntoIterator>::IntoIter; - - fn into_iter(self) -> Self::IntoIter { - self.data.into_iter() - } -} - -impl<'a, L: OwnedLockable<'a> + 'a> RefLockCollection<'a, L> { - /// Creates a new collection of owned locks. - /// - /// Because the locks are owned, there's no need to do any checks for - /// duplicate values. - /// - /// # Examples - /// - /// ``` - /// use happylock::{LockCollection, Mutex}; - /// - /// let data = (Mutex::new(0), Mutex::new("")); - /// let lock = LockCollection::new(&data); - /// ``` - #[must_use] - pub fn new(data: &'a L) -> RefLockCollection<L> { - RefLockCollection { - locks: get_locks(data), - data, - } - } -} - -impl<'a, L: Lockable<'a>> RefLockCollection<'a, L> { - /// Creates a new collections of locks. - /// - /// # Safety - /// - /// This results in undefined behavior if any locks are presented twice - /// within this collection. - /// - /// # Examples - /// - /// ``` - /// use happylock::{LockCollection, Mutex}; - /// - /// let data1 = Mutex::new(0); - /// let data2 = Mutex::new(""); - /// - /// // safety: data1 and data2 refer to distinct mutexes - /// let lock = unsafe { LockCollection::new_unchecked((&data1, &data2)) }; - /// ``` - #[must_use] - pub unsafe fn new_unchecked(data: &'a L) -> Self { - Self { - data, - locks: get_locks(data), - } - } - - /// Creates a new collection of locks. - /// - /// This returns `None` if any locks are found twice in the given - /// collection. - /// - /// # Examples - /// - /// ``` - /// use happylock::{LockCollection, Mutex}; - /// - /// let data1 = Mutex::new(0); - /// let data2 = Mutex::new(""); - /// - /// // data1 and data2 refer to distinct mutexes, so this won't panic - /// let lock = LockCollection::try_new((&data1, &data2)).unwrap(); - /// ``` - #[must_use] - pub fn try_new(data: &'a L) -> Option<Self> { - let locks = get_locks(data); - if contains_duplicates(&locks) { - return None; - } - - Some(Self { locks, data }) - } - - /// Locks the collection - /// - /// This function returns a guard that can be used to access the underlying - /// data. When the guard is dropped, the locks in the collection are also - /// dropped. - /// - /// # Examples - /// - /// ``` - /// use happylock::{LockCollection, Mutex, ThreadKey}; - /// - /// let key = ThreadKey::get().unwrap(); - /// let lock = LockCollection::new((Mutex::new(0), Mutex::new(""))); - /// - /// let mut guard = lock.lock(key); - /// *guard.0 += 1; - /// *guard.1 = "1"; - /// ``` - pub fn lock<'key: 'a, Key: Keyable + 'key>(&'a self, key: Key) -> LockGuard<'a, 'key, L, Key> { - for lock in &self.locks { - // safety: we have the thread key - unsafe { lock.lock() }; - } - - LockGuard { - // safety: we've already acquired the lock - guard: unsafe { self.data.guard() }, - key, - _phantom: PhantomData, - } - } - - /// Attempts to lock the without blocking. - /// - /// If successful, this method returns a guard that can be used to access - /// the data, and unlocks the data when it is dropped. Otherwise, `None` is - /// returned. - /// - /// # Examples - /// - /// ``` - /// use happylock::{LockCollection, Mutex, ThreadKey}; - /// - /// let key = ThreadKey::get().unwrap(); - /// let lock = LockCollection::new((Mutex::new(0), Mutex::new(""))); - /// - /// match lock.try_lock(key) { - /// Some(mut guard) => { - /// *guard.0 += 1; - /// *guard.1 = "1"; - /// }, - /// None => unreachable!(), - /// }; - /// - /// ``` - pub fn try_lock<'key: 'a, Key: Keyable + 'key>( - &'a self, - key: Key, - ) -> Option<LockGuard<'a, 'key, L, Key>> { - let guard = unsafe { - for (i, lock) in self.locks.iter().enumerate() { - // safety: we have the thread key - let success = lock.try_lock(); - - if !success { - for lock in &self.locks[0..i] { - // safety: this lock was already acquired - lock.unlock(); - } - return None; - } - } - - // safety: we've acquired the locks - self.data.guard() - }; - - Some(LockGuard { - guard, - key, - _phantom: PhantomData, - }) - } - - /// Unlocks the underlying lockable data type, returning the key that's - /// associated with it. - /// - /// # Examples - /// - /// ``` - /// use happylock::{LockCollection, Mutex, ThreadKey}; - /// - /// let key = ThreadKey::get().unwrap(); - /// let lock = LockCollection::new((Mutex::new(0), Mutex::new(""))); - /// - /// let mut guard = lock.lock(key); - /// *guard.0 += 1; - /// *guard.1 = "1"; - /// let key = LockCollection::unlock(guard); - /// ``` - #[allow(clippy::missing_const_for_fn)] - pub fn unlock<'key: 'a, Key: Keyable + 'key>(guard: LockGuard<'a, 'key, L, Key>) -> Key { - drop(guard.guard); - guard.key - } -} - -impl<'a, L: 'a> RefLockCollection<'a, L> -where - &'a L: IntoIterator, -{ - /// Returns an iterator over references to each value in the collection. - #[must_use] - pub fn iter(&'a self) -> <&'a L as IntoIterator>::IntoIter { - self.into_iter() - } -} |