Read-write lock for lilos

This provides a read-write lock for use with lilos.

See the API documentation for more.

lib.rs:

A read-write lock for use with lilos.

There's a small family of related types in this here crate:

• RwLock<T> contains some data of type T and allows either multiple shared references, or one exclusive reference, but not both simultaneously.
• SharedGuard<T> represents a shared reference to the data guarded by a RwLock and allows access to it (via Deref).
• ActionPermit<T> represents an exclusive reference to the data guarded by a RwLock, but once you start doing something that can modify the data, you can't await, to ensure that cancellation won't corrupt the guarded data.
• ExclusiveGuard<T> allows arbitrary exclusive access, even across await points, but you have to promise the library that the data is inherently cancel-safe (by using the lilos::util::CancelSafe marker type).

See the docs on RwLock for more details.