embed-collections 0.8.1

A collection of memory efficient and intrusive data structures
Documentation
#![cfg_attr(docsrs, feature(doc_cfg))]
#![cfg_attr(docsrs, allow(unused_attributes))]
#![cfg_attr(not(feature = "std"), no_std)]
#![doc = include_str!("../README.md")]

extern crate alloc;
#[cfg(any(feature = "std", test))]
extern crate std;

use alloc::boxed::Box;
use alloc::rc::Rc;
use alloc::sync::Arc;
use core::ptr::NonNull;

/// Abstract pointer trait to support various pointer types in collections.
///
/// This trait allows the collections to work with:
/// - `Box<T>`: Owned, automatically dropped.
/// - `Arc<T>`: Shared ownership.
/// - `Rc<T>`: Single thread ownership.
/// - `NonNull<T>`: Raw non-null pointers (manual memory management).
/// - `*const T`: Raw pointers (recommend to use `NonNull<T>` instead)
pub trait Pointer: Sized {
    type Target;

    fn as_ref(&self) -> &Self::Target;

    #[allow(clippy::missing_safety_doc)]
    unsafe fn from_raw(p: *const Self::Target) -> Self;

    fn into_raw(self) -> *const Self::Target;
}

#[allow(clippy::unnecessary_cast)]
impl<T> Pointer for *const T {
    type Target = T;

    #[inline]
    fn as_ref(&self) -> &Self::Target {
        unsafe { &**self }
    }

    unsafe fn from_raw(p: *const Self::Target) -> Self {
        p as *const T
    }

    fn into_raw(self) -> *const Self::Target {
        self as *const T
    }
}

#[allow(clippy::unnecessary_cast)]
impl<T> Pointer for *mut T {
    type Target = T;

    #[inline]
    fn as_ref(&self) -> &Self::Target {
        unsafe { &**self }
    }

    unsafe fn from_raw(p: *const Self::Target) -> Self {
        p as *mut T
    }

    fn into_raw(self) -> *const Self::Target {
        self as *mut T
    }
}

impl<T> Pointer for NonNull<T> {
    type Target = T;

    #[inline]
    fn as_ref(&self) -> &Self::Target {
        unsafe { self.as_ref() }
    }

    unsafe fn from_raw(p: *const Self::Target) -> Self {
        unsafe { NonNull::new_unchecked(p as *mut T) }
    }

    fn into_raw(self) -> *const Self::Target {
        self.as_ptr()
    }
}

impl<T> Pointer for Box<T> {
    type Target = T;

    #[inline]
    fn as_ref(&self) -> &Self::Target {
        self
    }

    unsafe fn from_raw(p: *const Self::Target) -> Self {
        unsafe { Box::from_raw(p as *mut T) }
    }

    fn into_raw(self) -> *const Self::Target {
        Box::into_raw(self)
    }
}

impl<T> Pointer for Rc<T> {
    type Target = T;

    #[inline]
    fn as_ref(&self) -> &Self::Target {
        self
    }

    unsafe fn from_raw(p: *const Self::Target) -> Self {
        unsafe { Rc::from_raw(p) }
    }

    fn into_raw(self) -> *const Self::Target {
        Rc::into_raw(self)
    }
}

impl<T> Pointer for Arc<T> {
    type Target = T;

    #[inline]
    fn as_ref(&self) -> &Self::Target {
        self
    }

    unsafe fn from_raw(p: *const Self::Target) -> Self {
        unsafe { Arc::from_raw(p) }
    }

    fn into_raw(self) -> *const Self::Target {
        Arc::into_raw(self)
    }
}

#[cfg(feature = "avl")]
pub mod avl;
pub mod const_vec;
pub use const_vec::ConstVec;
#[cfg(feature = "dlist")]
pub mod dlist;
pub mod seg_list;
pub use seg_list::SegList;
#[cfg(feature = "slist")]
pub mod slist;
#[cfg(feature = "slist")]
pub mod slist_owned;
pub mod various;
pub use various::Various;
#[cfg(feature = "btree")]
pub mod btree;
#[cfg(feature = "btree")]
pub use btree::BTreeMap;

#[cfg(test)]
pub mod test;

/// Cache line size in bytes
#[cfg(any(
    target_arch = "x86_64",
    target_arch = "aarch64",
    target_arch = "arm64ec",
    target_arch = "powerpc64",
))]
pub const CACHE_LINE_SIZE: usize = 64;
#[cfg(not(any(
    target_arch = "x86_64",
    target_arch = "aarch64",
    target_arch = "arm64ec",
    target_arch = "powerpc64",
)))]
pub const CACHE_LINE_SIZE: usize = 32;

/// logging macro for development
#[macro_export(local_inner_macros)]
macro_rules! trace_log {
    ($($arg:tt)+)=>{
        #[cfg(feature="trace_log")]
        {
            log::debug!($($arg)+);
        }
    };
}

/// logging macro for development
#[macro_export(local_inner_macros)]
macro_rules! print_log {
    ($($arg:tt)+)=>{
        #[cfg(feature="trace_log")]
        {
            log::debug!($($arg)+);
        }
        #[cfg(not(feature="trace_log"))]
        {
            std::println!($($arg)+);
        }
    };
}