nblf-queue 0.1.0

Atomic, wait-free MPMC queues based on the nblfq algorithm
Documentation 
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//! Core traits and types for interface with the queues in this crate.
//!
//! This module contains functionality which interacts with the underlying implementations of queues.
//! For most use cases it should not be neccessary to use any of this functionality.

pub(crate) mod buffer;
pub(crate) mod packed;
pub(crate) mod queue;
pub(crate) mod slot;

pub use packed::{AsPackedValue, TruncatedU64};

pub mod slots {
    //! Module containing types used to determine the underlying storage type in nblf-queue Queues.
    //! In most cases the `Auto` type, which is used as default across this crate, should suffice.

    use super::*;
    use crate::utils::Sealed;

    cfg_atomic_tagged64! {
        pub use tagged64::*;
        mod tagged64 {
            use super::*;
            /// Slot type describing a tagged 64 bit value.
            /// Only available if `target_has_atomic = "64"` is true or on feature `atomic-fallback`.
            pub struct Tagged64;
            impl Sealed for Tagged64 {}
            impl<T: AsPackedValue> SlotType<T> for Tagged64 {
                type Slot = slot::Tagged64<T>;
            }
        }
    }

    cfg_atomic_tagged128! {
        pub use tagged128::*;
        mod tagged128 {
            use super::*;
            /// Slot type describing a tagged 128 bit value.
            /// Only available if `target_has_atomic = "128"` is true or on feature `atomic-fallback`.
            pub struct Tagged128;
            impl Sealed for Tagged128 {}
            impl<T: AsPackedValue> SlotType<T> for Tagged128 {
                type Slot = slot::Tagged128<T>;
            }

        }
    }

    /// Slot type which chooses a concrete implementation based on arch and feature flags.
    pub struct Auto;
    impl Sealed for Auto {}

    #[doc(hidden)]
    pub trait SlotType<T: AsPackedValue>: Sealed {
        #[allow(private_bounds)]
        type Slot: slot::Slot<Item = T>;
    }

    impl<T: AsPackedValue> SlotType<T> for Auto {
        #[cfg(all(
            any(target_has_atomic = "64", feature = "atomic-fallback"),
            not(any(target_has_atomic = "128", feature = "atomic-fallback"))
        ))]
        type Slot = slot::Tagged64<T>;
        #[cfg(any(target_has_atomic = "128", feature = "atomic-fallback"))]
        type Slot = slot::Tagged128<T>;

        #[cfg(all(
            not(any(target_has_atomic = "64", feature = "atomic-fallback")),
            not(target_has_atomic = "128")
        ))]
        compile_error!("target arch is currently not supported");
    }
}