helper/ (#45)

* add `/helper/` * add `num.rs` * add `sys.rs` * add `crypto.rs` * add lints and mod to `lib.rs` * `sys` -> `time`, add more free functions straight from https://docs.rs/readable/latest/readable/time/index.html * num: add `Number/Float` types, `cmp_float()`, `cmp_float_nan()` * `common/src/tower_utils.rs` -> `helper/src/asynch.rs` * gate modules with `#[cfg(feature = "...")]` * add `thread.rs` * cargo fmt * thread: test out of 100 * add `atomic.rs` * atomic: fix `fetch_update()` * atomic: impl `fetch_*()` for atomic floats * `#[no_std]` where possible * asynch: remove `InstaFuture` https://docs.rs/futures/latest/futures/future/fn.ready.html * crypto: remove `check_point()` * thread: return percent computation without static * thread: add `low_priority_thread()` https://docs.rs/lpt * add rayon_spawn_async, remove crypto * remove current_time_try --------- Co-authored-by: Boog900 <54e72d8a-345f-4599-bd90-c6b9bc7d0ec5@aleeas.com>
2024-11-16 15:58:17 +00:00 · 2024-01-20 19:04:09 -05:00 · 2024-01-20 19:04:09 -05:00 · 50894bef89
commit 50894bef89
parent d10b9d3f8b
10 changed files with 1213 additions and 0 deletions
--- a/Cargo.lock
+++ b/Cargo.lock
@ -841,6 +841,18 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "95505c38b4572b2d910cecb0281560f54b440a19336cbbcb27bf6ce6adc6f5a8"
 [[package]]
 name = "helper"
 version = "0.1.0"
 dependencies = [
 "chrono",
 "futures",
 "libc",
 "rayon",
 "tokio",
 "windows",
 ]
 [[package]]
 name = "hermit-abi"
 version = "0.3.4"
@ -1051,6 +1063,16 @@ version = "0.4.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "01cda141df6706de531b6c46c3a33ecca755538219bd484262fa09410c13539c"
 [[package]]
 name = "lock_api"
 version = "0.4.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3c168f8615b12bc01f9c17e2eb0cc07dcae1940121185446edc3744920e8ef45"
 dependencies = [
 "autocfg",
 "scopeguard",
 ]
 [[package]]
 name = "log"
 version = "0.4.20"
@ -1327,6 +1349,29 @@ version = "2.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bb813b8af86854136c6922af0598d719255ecb2179515e6e7730d468f05c9cae"
 [[package]]
 name = "parking_lot"
 version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3742b2c103b9f06bc9fff0a37ff4912935851bee6d36f3c02bcc755bcfec228f"
 dependencies = [
 "lock_api",
 "parking_lot_core",
 ]
 [[package]]
 name = "parking_lot_core"
 version = "0.9.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4c42a9226546d68acdd9c0a280d17ce19bfe27a46bf68784e4066115788d008e"
 dependencies = [
 "cfg-if",
 "libc",
 "redox_syscall",
 "smallvec",
 "windows-targets 0.48.5",
 ]
 [[package]]
 name = "password-hash"
 version = "0.5.0"
@ -1719,6 +1764,12 @@ dependencies = [
 "windows-sys 0.52.0",
 ]
 [[package]]
 name = "scopeguard"
 version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 [[package]]
 name = "sct"
 version = "0.7.1"
@ -1828,6 +1879,15 @@ dependencies = [
 "lazy_static",
 ]
 [[package]]
 name = "signal-hook-registry"
 version = "1.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d8229b473baa5980ac72ef434c4415e70c4b5e71b423043adb4ba059f89c99a1"
 dependencies = [
 "libc",
 ]
 [[package]]
 name = "simple-request"
 version = "0.1.0"
@ -1995,10 +2055,13 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c89b4efa943be685f629b149f53829423f8f5531ea21249408e8e2f8671ec104"
 dependencies = [
 "backtrace",
 "bytes",
 "libc",
 "mio",
 "num_cpus",
 "parking_lot",
 "pin-project-lite",
 "signal-hook-registry",
 "socket2",
 "tokio-macros",
 "windows-sys 0.48.0",
@ -2318,6 +2381,16 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 [[package]]
 name = "windows"
 version = "0.52.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e48a53791691ab099e5e2ad123536d0fff50652600abaf43bbf952894110d0be"
 dependencies = [
 "windows-core",
 "windows-targets 0.52.0",
 ]
 [[package]]
 name = "windows-core"
 version = "0.52.0"
--- a/Cargo.toml
+++ b/Cargo.toml
@ -8,6 +8,7 @@ members = [
 	"cryptonight",
 	# "cuprate",
 	# "database",
 	"helper",
 	"net/levin",
 	"net/monero-wire",
 	"p2p/monero-p2p",
--- a/helper/Cargo.toml
+++ b/helper/Cargo.toml
@ -0,0 +1,30 @@
 [package]
 name = "helper"
 version = "0.1.0"
 edition = "2021"
 [features]
 # All features on by default.
 default = ["std", "atomic", "asynch", "num", "time", "thread"]
 std     = []
 atomic  = []
 asynch  = ["dep:futures", "dep:rayon"]
 num     = []
 time    = ["dep:chrono", "std"]
 thread  = ["std", "dep:target_os_lib"]
 [dependencies]
 chrono           = { workspace = true, optional = true }
 futures          = { workspace = true, optional = true }
 rayon            = { workspace = true, optional = true }
 # This is kinda a stupid work around.
 # [thread] needs to activate one of these libs (windows|libc)
 # although it depends on what target we're building for.
 [target.'cfg(windows)'.dependencies]
 target_os_lib = { package = "windows", version = ">=0.51", features = ["Win32_System_Threading", "Win32_Foundation"], optional = true }
 [target.'cfg(unix)'.dependencies]
 target_os_lib = { package = "libc", version = "0.2.151", optional = true }
 [dev-dependencies]
 tokio = { workspace = true }
--- a/helper/README.md
+++ b/helper/README.md
@ -0,0 +1,18 @@
 ## Helper
 `helper/` is the kitchen-sink crate for very generic, not necessarily Cuprate specific functions, types, etc.
 This allows all workspace crates to share, and aids compile times.
 If a 3rd party's crate/functions/types are small enough, it could be moved here to trim dependencies and allow easy modifications.
 ## Features
 Code can be selectively used/compiled with cargo's `--feature` or `features = ["..."]`.
 All features on by default.
 See [`Cargo.toml`](Cargo.toml)'s `[features]` table to see what features there are and what they enable.
 ## `#[no_std]`
 Each modules documents whether it requires `std` or not.
 If a module that requires `std` is enabled, `helper` will automatically use `std`.
--- a/helper/src/asynch.rs
+++ b/helper/src/asynch.rs
@ -0,0 +1,113 @@
 //! `async` related
 //!
 //! `#[no_std]` compatible.
 //---------------------------------------------------------------------------------------------------- Use
 use core::{
    future::Future,
    pin::Pin,
    task::{Context, Poll},
 };
 use futures::{channel::oneshot, FutureExt};
 //---------------------------------------------------------------------------------------------------- InfallibleOneshotReceiver
 /// A oneshot receiver channel that doesn't return an Error.
 ///
 /// This requires the sender to always return a response.
 pub struct InfallibleOneshotReceiver<T>(oneshot::Receiver<T>);
 impl<T> From<oneshot::Receiver<T>> for InfallibleOneshotReceiver<T> {
    fn from(value: oneshot::Receiver<T>) -> Self {
        InfallibleOneshotReceiver(value)
    }
 }
 impl<T> Future for InfallibleOneshotReceiver<T> {
    type Output = T;
    #[inline]
    fn poll(mut self: Pin<&mut Self>, ctx: &mut Context<'_>) -> Poll<Self::Output> {
        self.0
            .poll_unpin(ctx)
            .map(|res| res.expect("Oneshot must not be cancelled before response!"))
    }
 }
 //---------------------------------------------------------------------------------------------------- rayon_spawn_async
 /// Spawns a task for the rayon thread pool and awaits the result without blocking the async runtime.
 pub async fn rayon_spawn_async<F, R>(f: F) -> R
 where
    F: FnOnce() -> R + Send + 'static,
    R: Send + 'static,
 {
    let (tx, rx) = oneshot::channel();
    rayon::spawn(move || {
        let _ = tx.send(f());
    });
    rx.await.expect("The sender must not be dropped")
 }
 //---------------------------------------------------------------------------------------------------- Tests
 #[cfg(test)]
 mod test {
    use std::{
        sync::{Arc, Barrier},
        thread,
        time::Duration,
    };
    use super::*;
    #[tokio::test]
    // Assert that basic channel operations work.
    async fn infallible_oneshot_receiver() {
        let (tx, rx) = futures::channel::oneshot::channel::<String>();
        let msg = "hello world!".to_string();
        tx.send(msg.clone()).unwrap();
        let oneshot = InfallibleOneshotReceiver::from(rx);
        assert_eq!(oneshot.await, msg);
    }
    #[test]
    fn rayon_spawn_async_does_not_block() {
        // There must be more than 1 rayon thread for this to work.
        rayon::ThreadPoolBuilder::new()
            .num_threads(2)
            .build_global()
            .unwrap();
        // We use a barrier to make sure both tasks are executed together, we block the rayon thread
        // until both rayon threads are blocked.
        let barrier = Arc::new(Barrier::new(2));
        let task = |barrier: &Barrier| barrier.wait();
        let b_2 = barrier.clone();
        let (tx, rx) = std::sync::mpsc::channel();
        thread::spawn(move || {
            let runtime = tokio::runtime::Builder::new_current_thread()
                .enable_all()
                .build()
                .unwrap();
            runtime.block_on(async {
                tokio::join!(
                    // This polls them concurrently in the same task, so if the first one blocks the task then
                    // the second wont run and if the second does not run the first does not unblock.
                    rayon_spawn_async(move || task(&barrier)),
                    rayon_spawn_async(move || task(&b_2)),
                )
            });
            // if we managed to get here then rayon_spawn_async didn't block.
            tx.send(()).unwrap();
        });
        rx.recv_timeout(Duration::from_secs(2))
            .expect("rayon_spawn_async blocked");
    }
 }
--- a/helper/src/atomic.rs
+++ b/helper/src/atomic.rs
@ -0,0 +1,490 @@
 //! Atomic related
 //!
 //! `#[no_std]` compatible.
 //---------------------------------------------------------------------------------------------------- Use
 use core::sync::atomic::{AtomicU32, AtomicU64, Ordering};
 //---------------------------------------------------------------------------------------------------- Atomic Float
 // An AtomicF(32|64) implementation.
 //
 // This internally uses [AtomicU(32|64)], where the
 // u(32|64) is the bit pattern of the internal float.
 //
 // This uses [.to_bits()] and [from_bits()] to
 // convert between actual floats, and the bit
 // representations for storage.
 //
 // Using `UnsafeCell<float>` is also viable,
 // and would allow for a `const fn new(f: float) -> Self`
 // except that becomes problematic with NaN's and infinites:
 // - https://github.com/rust-lang/rust/issues/73328
 // - https://github.com/rust-lang/rfcs/pull/3514
 //
 // This is most likely safe(?) but... instead of risking UB,
 // this just uses the Atomic unsigned integer as the inner
 // type instead of transmuting from `UnsafeCell`.
 //
 // This creates the types:
 // - `AtomicF32`
 // - `AtomicF64`
 //
 // Originally taken from:
 // https://github.com/hinto-janai/sansan/blob/1f6680b2d08ff5fbf4f090178ea5233d4cf9056f/src/atomic.rs
 macro_rules! impl_atomic_f {
    (
 		$atomic_float:ident,       // Name of the new float type
 		$atomic_float_lit:literal, // Literal name of new float type
 		$float:ident,              // The target float (f32/f64)
 		$unsigned:ident,           // The underlying unsigned type
 		$atomic_unsigned:ident,    // The underlying unsigned atomic type
 		$bits_0:literal,           // Bit pattern for 0.0
 		$bits_025:literal,         // Bit pattern for 0.25
 		$bits_050:literal,         // Bit pattern for 0.50
 		$bits_075:literal,         // Bit pattern for 0.75
 		$bits_1:literal,           // Bit pattern for 1.0
 	) => {
        /// An atomic float.
        ///
        /// ## Portability
        /// [Quoting the std library: ](https://doc.rust-lang.org/1.70.0/std/primitive.f32.html#method.to_bits)
        /// "See from_bits for some discussion of the portability of this operation (there are almost no issues)."
        ///
        /// ## Compile-time failure
        /// This internal functions `std` uses will panic _at compile time_
        /// if the bit transmutation operations it uses are not available
        /// on the build target, aka, if it compiles we're probably safe.
        #[repr(transparent)]
        #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
        #[cfg_attr(feature = "bincode", derive(bincode::Encode, bincode::Decode))]
        pub struct $atomic_float($atomic_unsigned);
        impl $atomic_float {
            /// Representation of `0.0` as bits, can be inputted into [`Self::from_bits`].
            pub const BITS_0: $unsigned = $bits_0;
            /// Representation of `0.25` as bits, can be inputted into [`Self::from_bits`].
            pub const BITS_0_25: $unsigned = $bits_025;
            /// Representation of `0.50` as bits, can be inputted into [`Self::from_bits`].
            pub const BITS_0_50: $unsigned = $bits_050;
            /// Representation of `0.75` as bits, can be inputted into [`Self::from_bits`].
            pub const BITS_0_75: $unsigned = $bits_075;
            /// Representation of `1.0` as bits, can be inputted into [`Self::from_bits`].
            pub const BITS_0_100: $unsigned = $bits_1;
            #[allow(clippy::declare_interior_mutable_const)]
            // FIXME:
            // Seems like `std` internals has some unstable cfg options that
            // allow interior mutable consts to be defined without clippy complaining:
            // https://doc.rust-lang.org/1.70.0/src/core/sync/atomic.rs.html#3013.
            //
            /// `0.0`, returned by [`Self::default`].
            pub const DEFAULT: Self = Self($atomic_unsigned::new($bits_0));
            #[inline]
            /// Create a new atomic float.
            ///
            /// Equivalent to https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.new
            pub fn new(f: $float) -> Self {
                // FIXME: Update to const when available.
                // https://doc.rust-lang.org/1.70.0/src/core/num/f32.rs.html#998
                //
                // `transmute()` here would be safe (`to_bits()` is doing this)
                // although checking for NaN's and infinites are non-`const`...
                // so we can't can't `transmute()` even though it would allow
                // this function to be `const`.
                Self($atomic_unsigned::new(f.to_bits()))
            }
            #[inline]
            /// Equivalent to https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.into_inner
            pub fn into_inner(self) -> $float {
                $float::from_bits(self.0.into_inner())
            }
            #[inline]
            /// Create a new atomic float, from the unsigned bit representation.
            pub const fn from_bits(bits: $unsigned) -> Self {
                Self($atomic_unsigned::new(bits))
            }
            #[inline]
            /// Store a float inside the atomic.
            ///
            /// Equivalent to https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.store
            pub fn store(&self, f: $float, ordering: Ordering) {
                self.0.store(f.to_bits(), ordering);
            }
            #[inline]
            /// Store a bit representation of a float inside the atomic.
            pub fn store_bits(&self, bits: $unsigned, ordering: Ordering) {
                self.0.store(bits, ordering);
            }
            #[inline]
            /// Load the internal float from the atomic.
            ///
            /// Equivalent to https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.load
            pub fn load(&self, ordering: Ordering) -> $float {
                // FIXME: Update to const when available.
                // https://doc.rust-lang.org/1.70.0/src/core/num/f32.rs.html#1088
                $float::from_bits(self.0.load(ordering))
            }
            #[inline]
            /// Load the internal bit representation of the float from the atomic.
            pub fn load_bits(&self, ordering: Ordering) -> $unsigned {
                self.0.load(ordering)
            }
            #[inline]
            /// Equivalent to https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.swap
            pub fn swap(&self, val: $float, ordering: Ordering) -> $float {
                $float::from_bits(self.0.swap($float::to_bits(val), ordering))
            }
            #[inline]
            /// Equivalent to https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.compare_exchange
            pub fn compare_exchange(
                &self,
                current: $float,
                new: $float,
                success: Ordering,
                failure: Ordering,
            ) -> Result<$float, $float> {
                match self
                    .0
                    .compare_exchange(current.to_bits(), new.to_bits(), success, failure)
                {
                    Ok(b) => Ok($float::from_bits(b)),
                    Err(b) => Err($float::from_bits(b)),
                }
            }
            #[inline]
            /// Equivalent to https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.compare_exchange_weak
            pub fn compare_exchange_weak(
                &self,
                current: $float,
                new: $float,
                success: Ordering,
                failure: Ordering,
            ) -> Result<$float, $float> {
                match self.0.compare_exchange_weak(
                    current.to_bits(),
                    new.to_bits(),
                    success,
                    failure,
                ) {
                    Ok(b) => Ok($float::from_bits(b)),
                    Err(b) => Err($float::from_bits(b)),
                }
            }
            //------------------------------------------------------------------ fetch_*()
            // These are tricky to implement because we must
            // operate on the _numerical_ value and not the
            // bit representations.
            //
            // This means using some type of CAS,
            // which comes with the regular tradeoffs...
            // The (private) function using CAS to implement `fetch_*()` operations.
            //
            // This is function body used in all the below `fetch_*()` functions.
            fn fetch_update_unwrap<F>(&self, ordering: Ordering, mut update: F) -> $float
            where
                F: FnMut($float) -> $float,
            {
                // Since it's a CAS, we need a second ordering for failures,
                // this will take the user input and return an appropriate order.
                let second_order = match ordering {
                    Ordering::Release | Ordering::Relaxed => Ordering::Relaxed,
                    Ordering::Acquire | Ordering::AcqRel => Ordering::Acquire,
                    Ordering::SeqCst => Ordering::SeqCst,
                    // Ordering is #[non_exhaustive], so we must do this.
                    ordering => ordering,
                };
                // SAFETY:
                // unwrap is safe since `fetch_update()` only panics
                // if the closure we pass it returns `None`.
                // As seen below, we're passing a `Some`.
                //
                // https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.fetch_update
                self.fetch_update(ordering, second_order, |f| Some(update(f)))
                    .unwrap()
            }
            #[inline]
            /// This function is implemented with [`Self::fetch_update`], and is not 100% equivalent to
            /// https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.fetch_add.
            ///
            /// In particular, this method will not circumvent the [ABA Problem](https://en.wikipedia.org/wiki/ABA_problem).
            ///
            /// Other than this not actually being atomic, all other behaviors are the same.
            pub fn fetch_add(&self, val: $float, order: Ordering) -> $float {
                self.fetch_update_unwrap(order, |f| f + val)
            }
            #[inline]
            /// This function is implemented with [`Self::fetch_update`], and is not 100% equivalent to
            /// https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.fetch_sub.
            ///
            /// In particular, this method will not circumvent the [ABA Problem](https://en.wikipedia.org/wiki/ABA_problem).
            ///
            /// Other than this not actually being atomic, all other behaviors are the same.
            pub fn fetch_sub(&self, val: $float, order: Ordering) -> $float {
                self.fetch_update_unwrap(order, |f| f - val)
            }
            #[inline]
            /// This function is implemented with [`Self::fetch_update`], and is not 100% equivalent to
            /// https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.fetch_max.
            ///
            /// In particular, this method will not circumvent the [ABA Problem](https://en.wikipedia.org/wiki/ABA_problem).
            ///
            /// Other than this not actually being atomic, all other behaviors are the same.
            pub fn fetch_max(&self, val: $float, order: Ordering) -> $float {
                self.fetch_update_unwrap(order, |f| f.max(val))
            }
            #[inline]
            /// This function is implemented with [`Self::fetch_update`], and is not 100% equivalent to
            /// https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.fetch_min.
            ///
            /// In particular, this method will not circumvent the [ABA Problem](https://en.wikipedia.org/wiki/ABA_problem).
            ///
            /// Other than this not actually being atomic, all other behaviors are the same.
            pub fn fetch_min(&self, val: $float, order: Ordering) -> $float {
                self.fetch_update_unwrap(order, |f| f.min(val))
            }
            #[inline]
            /// Equivalent to https://doc.rust-lang.org/1.70.0/std/sync/atomic/struct.AtomicUsize.html#method.fetch_update
            pub fn fetch_update<F>(
                &self,
                set_order: Ordering,
                fetch_order: Ordering,
                mut f: F,
            ) -> Result<$float, $float>
            where
                F: FnMut($float) -> Option<$float>,
            {
                // Very unreadable closure...
                //
                // Basically this is converting:
                //   `f(f32) -> Option<f32>` into `f(u32) -> Option<u32>`
                // so the internal atomic `fetch_update` can work.
                let f = |bits: $unsigned| f($float::from_bits(bits)).map(|f| $float::to_bits(f));
                match self.0.fetch_update(set_order, fetch_order, f) {
                    Ok(b) => Ok($float::from_bits(b)),
                    Err(b) => Err($float::from_bits(b)),
                }
            }
            #[inline]
            /// Set the internal float from the atomic, using [`Ordering::Release`].
            pub fn set(&self, f: $float) {
                self.store(f, Ordering::Release);
            }
            #[inline]
            /// Get the internal float from the atomic, using [`Ordering::Acquire`].
            pub fn get(&self) -> $float {
                self.load(Ordering::Acquire)
            }
        }
        impl From<$float> for $atomic_float {
            /// Calls [`Self::new`]
            fn from(float: $float) -> Self {
                Self::new(float)
            }
        }
        impl Default for $atomic_float {
            /// Returns `0.0`.
            fn default() -> Self {
                Self::DEFAULT
            }
        }
        impl std::fmt::Debug for $atomic_float {
            /// This prints the internal float value, using [`Ordering::Acquire`].
            ///
            /// # Panics
            /// This panics on NaN or subnormal float inputs.
            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
                f.debug_tuple($atomic_float_lit)
                    .field(&self.0.load(Ordering::Acquire))
                    .finish()
            }
        }
    };
 }
 impl_atomic_f! {
    AtomicF64,
    "AtomicF64",
    f64,
    u64,
    AtomicU64,
    0,
    4598175219545276416,
    4602678819172646912,
    4604930618986332160,
    4607182418800017408,
 }
 impl_atomic_f! {
    AtomicF32,
    "AtomicF32",
    f32,
    u32,
    AtomicU32,
    0,
    1048576000,
    1056964608,
    1061158912,
    1065353216,
 }
 //---------------------------------------------------------------------------------------------------- TESTS
 #[cfg(test)]
 mod tests {
    use super::*;
    // These tests come in pairs, `f32|f64`.
    //
    // If changing one, update the other as well.
    //
    // `macro_rules!()` + `paste!()` could do this automatically,
    // but that might be more trouble than it's worth...
    #[test]
    // Tests the varying fetch, swap, and compare functions.
    fn f32_functions() {
        let float = AtomicF32::new(5.0);
        let ordering = Ordering::SeqCst;
        // Loads/Stores
        assert_eq!(float.swap(1.0, ordering), 5.0);
        assert_eq!(float.load(ordering), 1.0);
        float.store(2.0, ordering);
        assert_eq!(float.load(ordering), 2.0);
        // CAS
        assert_eq!(
            float.compare_exchange(2.0, 5.0, ordering, ordering),
            Ok(2.0)
        );
        assert_eq!(
            float.fetch_update(ordering, ordering, |f| Some(f * 3.0)),
            Ok(5.0)
        );
        assert_eq!(float.get(), 15.0);
        loop {
            if let Ok(float) = float.compare_exchange_weak(15.0, 2.0, ordering, ordering) {
                assert_eq!(float, 15.0);
                break;
            }
        }
        // `fetch_*()` functions
        assert_eq!(float.fetch_add(1.0, ordering), 2.0);
        assert_eq!(float.fetch_sub(1.0, ordering), 3.0);
        assert_eq!(float.fetch_max(5.0, ordering), 2.0);
        assert_eq!(float.fetch_min(0.0, ordering), 5.0);
    }
    #[test]
    fn f64_functions() {
        let float = AtomicF64::new(5.0);
        let ordering = Ordering::SeqCst;
        assert_eq!(float.swap(1.0, ordering), 5.0);
        assert_eq!(float.load(ordering), 1.0);
        float.store(2.0, ordering);
        assert_eq!(float.load(ordering), 2.0);
        assert_eq!(
            float.compare_exchange(2.0, 5.0, ordering, ordering),
            Ok(2.0)
        );
        assert_eq!(
            float.fetch_update(ordering, ordering, |f| Some(f * 3.0)),
            Ok(5.0)
        );
        assert_eq!(float.get(), 15.0);
        loop {
            if let Ok(float) = float.compare_exchange_weak(15.0, 2.0, ordering, ordering) {
                assert_eq!(float, 15.0);
                break;
            }
        }
        assert_eq!(float.fetch_add(1.0, ordering), 2.0);
        assert_eq!(float.fetch_sub(1.0, ordering), 3.0);
        assert_eq!(float.fetch_max(5.0, ordering), 2.0);
        assert_eq!(float.fetch_min(0.0, ordering), 5.0);
    }
    #[test]
    fn f32_bits() {
        assert_eq!(AtomicF32::default().get(), 0.00);
        assert_eq!(AtomicF32::from_bits(AtomicF32::BITS_0).get(), 0.00);
        assert_eq!(AtomicF32::from_bits(AtomicF32::BITS_0_25).get(), 0.25);
        assert_eq!(AtomicF32::from_bits(AtomicF32::BITS_0_50).get(), 0.50);
        assert_eq!(AtomicF32::from_bits(AtomicF32::BITS_0_75).get(), 0.75);
        assert_eq!(AtomicF32::from_bits(AtomicF32::BITS_0_100).get(), 1.00);
    }
    #[test]
    fn f64_bits() {
        assert_eq!(AtomicF64::default().get(), 0.00);
        assert_eq!(AtomicF64::from_bits(AtomicF64::BITS_0).get(), 0.00);
        assert_eq!(AtomicF64::from_bits(AtomicF64::BITS_0_25).get(), 0.25);
        assert_eq!(AtomicF64::from_bits(AtomicF64::BITS_0_50).get(), 0.50);
        assert_eq!(AtomicF64::from_bits(AtomicF64::BITS_0_75).get(), 0.75);
        assert_eq!(AtomicF64::from_bits(AtomicF64::BITS_0_100).get(), 1.00);
    }
    #[test]
    fn f32_0_to_100() {
        let mut i = 0.0;
        let f = AtomicF32::new(0.0);
        while i < 100.0 {
            f.set(i);
            assert_eq!(f.get(), i);
            i += 0.1;
        }
    }
    #[test]
    fn f64_0_to_100() {
        let mut i = 0.0;
        let f = AtomicF64::new(0.0);
        while i < 100.0 {
            f.set(i);
            assert_eq!(f.get(), i);
            i += 0.1;
        }
    }
    #[test]
    fn f32_irregular() {
        assert!(AtomicF32::new(f32::NAN).get().is_nan());
        assert_eq!(AtomicF32::new(f32::INFINITY).get(), f32::INFINITY);
        assert_eq!(AtomicF32::new(f32::NEG_INFINITY).get(), f32::NEG_INFINITY);
    }
    #[test]
    fn f64_irregular() {
        assert!(AtomicF64::new(f64::NAN).get().is_nan());
        assert_eq!(AtomicF64::new(f64::INFINITY).get(), f64::INFINITY);
        assert_eq!(AtomicF64::new(f64::NEG_INFINITY).get(), f64::NEG_INFINITY);
    }
 }
--- a/helper/src/lib.rs
+++ b/helper/src/lib.rs
@ -0,0 +1,50 @@
 #![doc = include_str!("../README.md")]
 //---------------------------------------------------------------------------------------------------- Lints
 #![allow(clippy::len_zero, clippy::type_complexity, clippy::module_inception)]
 #![deny(nonstandard_style, deprecated, missing_docs, unused_mut)]
 #![forbid(
    unused_unsafe,
    future_incompatible,
    break_with_label_and_loop,
    coherence_leak_check,
    duplicate_macro_attributes,
    exported_private_dependencies,
    for_loops_over_fallibles,
    large_assignments,
    overlapping_range_endpoints,
    // private_in_public,
    semicolon_in_expressions_from_macros,
    redundant_semicolons,
    unconditional_recursion,
    unreachable_patterns,
    unused_allocation,
    unused_braces,
    unused_comparisons,
    unused_doc_comments,
    unused_parens,
    unused_labels,
    while_true,
    keyword_idents,
    non_ascii_idents,
    noop_method_call,
 	unreachable_pub,
    single_use_lifetimes,
 	// variant_size_differences,
 )]
 #![cfg_attr(not(feature = "std"), no_std)]
 //---------------------------------------------------------------------------------------------------- Public API
 #[cfg(feature = "asynch")]
 pub mod asynch; // async collides
 #[cfg(feature = "atomic")]
 pub mod atomic;
 #[cfg(feature = "num")]
 pub mod num;
 #[cfg(feature = "thread")]
 pub mod thread;
 #[cfg(feature = "time")]
 pub mod time;
 //---------------------------------------------------------------------------------------------------- Private Usage
 //----------------------------------------------------------------------------------------------------
--- a/helper/src/num.rs
+++ b/helper/src/num.rs
@ -0,0 +1,177 @@
 //! Number related
 //!
 //! `#[no_std]` compatible.
 //---------------------------------------------------------------------------------------------------- Use
 use core::{
    cmp::Ordering,
    ops::{Add, Div, Mul, Sub},
 };
 //---------------------------------------------------------------------------------------------------- Types
 // INVARIANT: must be private.
 // Protects against outside-crate implementations.
 mod private {
    pub trait Sealed: Copy + PartialOrd<Self> + core::fmt::Display {}
 }
 /// Non-floating point numbers
 ///
 /// This trait is sealed and is only implemented on:
 /// - [`u8`] to [`u128`] and [`usize`]
 /// - [`i8`] to [`i128`] and [`isize`]
 pub trait Number: private::Sealed {}
 macro_rules! impl_number {
    ($($num:ty),* $(,)?) => {
        $(
            impl Number for $num {}
            impl private::Sealed for $num {}
        )*
    };
 }
 impl_number!(u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize);
 /// Floating point numbers
 ///
 /// This trait is sealed and is only implemented on:
 /// - [`f32`]
 /// - [`f64`]
 pub trait Float: private::Sealed {}
 macro_rules! impl_float {
    ($($num:ty),* $(,)?) => {
        $(
            impl Float for $num {}
            impl private::Sealed for $num {}
        )*
    };
 }
 impl_float!(f32, f64);
 //---------------------------------------------------------------------------------------------------- Free Functions
 #[inline]
 /// Returns the average of two numbers; works with at least all integral and floating point types
 ///
 /// ```rust
 /// # use helper::num::*;
 /// assert_eq!(get_mid(0,        10),       5);
 /// assert_eq!(get_mid(0.0,      10.0),     5.0);
 /// assert_eq!(get_mid(-10.0,    10.0),     0.0);
 /// assert_eq!(get_mid(i16::MIN, i16::MAX), -1);
 /// assert_eq!(get_mid(u8::MIN,  u8::MAX),  127);
 ///
 /// assert!(get_mid(f32::NAN, f32::NAN).is_nan());
 /// assert!(get_mid(f32::NEG_INFINITY, f32::INFINITY).is_nan());
 /// ```
 pub fn get_mid<T>(a: T, b: T) -> T
 where
    T: Add<Output = T> + Sub<Output = T> + Div<Output = T> + Mul<Output = T> + Copy + From<u8>,
 {
    let two: T = 2_u8.into();
    // https://github.com/monero-project/monero/blob/90294f09ae34ef96f3dea5fea544816786df87c8/contrib/epee/include/misc_language.h#L43
    (a / two) + (b / two) + ((a - two * (a / two)) + (b - two * (b / two))) / two
 }
 #[inline]
 /// Gets the median from a sorted slice.
 ///
 /// ```rust
 /// # use helper::num::*;
 /// let mut vec = vec![10, 5, 1, 4, 2, 8, 9, 7, 3, 6];
 /// vec.sort();
 ///
 /// assert_eq!(median(vec), 5);
 /// ```
 ///
 /// # Safety
 /// If not sorted the output will be invalid.
 pub fn median<T>(array: impl AsRef<[T]>) -> T
 where
    T: Add<Output = T> + Sub<Output = T> + Div<Output = T> + Mul<Output = T> + Copy + From<u8>,
 {
    let array = array.as_ref();
    let len = array.len();
    let mid = len / 2;
    if len == 1 {
        return array[0];
    }
    if len % 2 == 0 {
        get_mid(array[mid - 1], array[mid])
    } else {
        array[mid]
    }
 }
 #[inline]
 /// Compare 2 non-`NaN` floats.
 ///
 /// ```rust
 /// # use helper::num::*;
 /// # use core::cmp::Ordering;
 /// assert_eq!(cmp_float(0.0, 1.0), Ordering::Less);
 /// assert_eq!(cmp_float(1.0, 1.0), Ordering::Equal);
 /// assert_eq!(cmp_float(2.0, 1.0), Ordering::Greater);
 ///
 /// assert_eq!(cmp_float(1.0,           f32::INFINITY), Ordering::Less);
 /// assert_eq!(cmp_float(f32::INFINITY, f32::INFINITY), Ordering::Equal);
 /// assert_eq!(cmp_float(f32::INFINITY, 1.0),           Ordering::Greater);
 ///
 /// assert_eq!(cmp_float(f32::NEG_INFINITY, f32::INFINITY),     Ordering::Less);
 /// assert_eq!(cmp_float(f32::NEG_INFINITY, f32::NEG_INFINITY), Ordering::Equal);
 /// assert_eq!(cmp_float(f32::INFINITY,     f32::NEG_INFINITY), Ordering::Greater);
 /// ```
 ///
 /// # Panic
 /// This function panics if either floats are NaNs.
 ///
 /// ```rust,should_panic
 /// # use helper::num::*;
 /// cmp_float(0.0, f32::NAN);
 /// ```
 pub fn cmp_float<F: Float>(a: F, b: F) -> Ordering {
    match (a <= b, a >= b) {
        (false, true) => Ordering::Greater,
        (true, false) => Ordering::Less,
        (true, true) => Ordering::Equal,
        _ => panic!("cmp_float() has failed, input: {a} - {b}"),
    }
 }
 #[inline]
 /// Compare 2 floats, `NaN`'s will always return [`Ordering::Equal`].
 ///
 /// ```rust
 /// # use helper::num::*;
 /// # use core::cmp::Ordering;
 /// assert_eq!(cmp_float_nan(0.0, 1.0), Ordering::Less);
 /// assert_eq!(cmp_float_nan(1.0, 1.0), Ordering::Equal);
 /// assert_eq!(cmp_float_nan(2.0, 1.0), Ordering::Greater);
 ///
 /// assert_eq!(cmp_float_nan(1.0,           f32::INFINITY), Ordering::Less);
 /// assert_eq!(cmp_float_nan(f32::INFINITY, f32::INFINITY), Ordering::Equal);
 /// assert_eq!(cmp_float_nan(f32::INFINITY, 1.0),           Ordering::Greater);
 ///
 /// assert_eq!(cmp_float_nan(f32::NEG_INFINITY, f32::INFINITY),     Ordering::Less);
 /// assert_eq!(cmp_float_nan(f32::NEG_INFINITY, f32::NEG_INFINITY), Ordering::Equal);
 /// assert_eq!(cmp_float_nan(f32::INFINITY,     f32::NEG_INFINITY), Ordering::Greater);
 ///
 /// assert_eq!(cmp_float_nan(f32::NAN, -0.0),              Ordering::Equal);
 /// assert_eq!(cmp_float_nan(f32::NAN, 0.0),               Ordering::Equal);
 /// assert_eq!(cmp_float_nan(f32::NAN, f32::NAN),          Ordering::Equal);
 /// assert_eq!(cmp_float_nan(f32::NAN, f32::INFINITY),     Ordering::Equal);
 /// assert_eq!(cmp_float_nan(f32::NAN, f32::NEG_INFINITY), Ordering::Equal);
 /// ```
 pub fn cmp_float_nan<F: Float>(a: F, b: F) -> Ordering {
    match (a <= b, a >= b) {
        (false, true) => Ordering::Greater,
        (true, false) => Ordering::Less,
        _ => Ordering::Equal,
    }
 }
 //---------------------------------------------------------------------------------------------------- Tests
 #[cfg(test)]
 mod test {}
--- a/helper/src/thread.rs
+++ b/helper/src/thread.rs
@ -0,0 +1,100 @@
 //! System thread related
 //!
 //! Requires `std`.
 //---------------------------------------------------------------------------------------------------- Use
 use std::{cmp::max, num::NonZeroUsize};
 //---------------------------------------------------------------------------------------------------- Constants
 // FIXME: switch to `.unwrap()` when const stablized
 const NON_ZERO_USIZE_1: NonZeroUsize = match NonZeroUsize::new(1) {
    Some(t) => t,
    _ => panic!(),
 };
 //---------------------------------------------------------------------------------------------------- Thread Count & Percent
 #[allow(non_snake_case)]
 /// Get the total amount of system threads.
 ///
 /// ```rust
 /// # use helper::thread::*;
 /// assert!(threads().get() >= 1);
 /// ```
 pub fn threads() -> NonZeroUsize {
    std::thread::available_parallelism().unwrap_or(NON_ZERO_USIZE_1)
 }
 // Implement a function for the various
 // `x` thread-percent functions below.
 macro_rules! impl_thread_percent {
    ($(
    	$(#[$doc:meta])*
    	$fn_name:ident => // Name of the function
 		$percent:literal  // The target percent of threads
 	),* $(,)?) => {
 		$(
 			$(#[$doc])*
 			pub fn $fn_name() -> NonZeroUsize {
 		        // SAFETY:
 		        // unwrap here is okay because:
 		        // - THREADS().get() is always non-zero
 		        // - max() guards against 0
 		        NonZeroUsize::new(max(1, (threads().get() as f64 * $percent).floor() as usize)).unwrap()
 		    }
 		)*
    }
 }
 impl_thread_percent! {
    /// Get 90% (rounded down) of available amount of system threads.
    threads_90 => 0.90,
    /// Get 75% (rounded down) of available amount of system threads.
    threads_75 => 0.75,
    /// Get 50% (rounded down) of available amount of system threads.
    threads_50 => 0.50,
    /// Get 25% (rounded down) of available amount of system threads.
    threads_25 => 0.25,
    /// Get 10% (rounded down) of available amount of system threads.
    threads_10 => 0.10,
 }
 //---------------------------------------------------------------------------------------------------- Thread Priority
 /// Low Priority Thread
 ///
 /// Sets the calling thread’s priority to the lowest platform-specific value possible.
 ///
 /// https://docs.rs/lpt
 ///
 /// # Windows
 /// Uses SetThreadPriority() with THREAD_PRIORITY_IDLE (-15).
 ///
 /// # Unix
 /// Uses libc::nice() with the max nice level.
 ///
 /// On macOS and *BSD: +20
 /// On Linux: +19
 pub fn low_priority_thread() {
    #[cfg(target_os = "windows")]
    {
        use target_os_lib as windows;
        use windows::Win32::System::Threading::*;
        // SAFETY: calling C.
        // We are _lowering_ our priority, not increasing, so this function should never fail.
        unsafe { SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_IDLE) };
    }
    #[cfg(target_family = "unix")]
    {
        use target_os_lib as libc;
        const NICE_MAX: libc::c_int = if cfg!(target_os = "linux") { 19 } else { 20 };
        // SAFETY: calling C.
        // We are _lowering_ our priority, not increasing, so this function should never fail.
        unsafe { libc::nice(NICE_MAX) };
    }
 }
 //---------------------------------------------------------------------------------------------------- TESTS
 #[cfg(test)]
 mod tests {}
--- a/helper/src/time.rs
+++ b/helper/src/time.rs
@ -0,0 +1,161 @@
 //! System related
 //!
 //! Requires `std`.
 //---------------------------------------------------------------------------------------------------- Use
 use std::time::{SystemTime, UNIX_EPOCH};
 //---------------------------------------------------------------------------------------------------- Public API
 #[inline]
 /// Returns the current system time as a UNIX timestamp.
 ///
 /// ```rust
 /// # use helper::time::*;
 /// assert!(current_unix_timestamp() > 0);
 /// ```
 ///
 /// # Panics
 /// This function panics if the call to get the system time fails.
 pub fn current_unix_timestamp() -> u64 {
    SystemTime::now()
        .duration_since(UNIX_EPOCH)
        .unwrap()
        .as_secs()
 }
 #[inline]
 /// Get the clock time of a UNIX timestamp
 ///
 /// The input must be a UNIX timestamp.
 ///
 /// The returned `u64` will represent how many seconds has
 /// passed on the day corresponding to that timestamp.
 ///
 /// The output is guaranteed to be in the range of `0..=86399`.
 ///
 /// ```rust
 /// # use helper::time::*;
 /// // October 20th 2023 - 10:18:30 PM
 /// const TIME: u64 = 1697840310;
 ///
 /// let seconds = unix_clock(TIME);
 /// assert_eq!(seconds, 80310);
 ///
 /// let (h, m, s) = secs_to_clock(seconds);
 /// // 10:18:30 PM.
 /// assert_eq!((h, m, s), (22, 18, 30))
 /// ```
 pub const fn unix_clock(seconds_after_unix_epoch: u64) -> u32 {
    (seconds_after_unix_epoch % 86400) as _
 }
 #[inline]
 /// Convert seconds to `hours`, `minutes` and `seconds`.
 ///
 /// - The seconds returned is guaranteed to be `0..=59`
 /// - The minutes returned is guaranteed to be `0..=59`
 /// - The hours returned can be over `23`, as this is not a clock function,
 /// see [`secs_to_clock`] for clock-like behavior that wraps around on `24`
 ///
 /// ```rust
 /// # use helper::time::*;
 /// // 59 seconds.
 /// assert_eq!(secs_to_hms(59), (0, 0, 59));
 ///
 /// // 1 minute.
 /// assert_eq!(secs_to_hms(60), (0, 1, 0));
 ///
 /// // 59 minutes, 59 seconds.
 /// assert_eq!(secs_to_hms(3599), (0, 59, 59));
 ///
 /// // 1 hour.
 /// assert_eq!(secs_to_hms(3600), (1, 0, 0));
 ///
 /// // 23 hours, 59 minutes, 59 seconds.
 /// assert_eq!(secs_to_hms(86399), (23, 59, 59));
 ///
 /// // 24 hours.
 /// assert_eq!(secs_to_hms(86400), (24, 0, 0));
 /// ```
 pub const fn secs_to_hms(seconds: u64) -> (u64, u8, u8) {
    let hours = seconds / 3600;
    let minutes = (seconds % 3600) / 60;
    let seconds = (seconds % 3600) % 60;
    debug_assert!(minutes < 60);
    debug_assert!(seconds < 60);
    (hours, minutes as u8, seconds as u8)
 }
 #[inline]
 /// Convert seconds to clock time, `hours`, `minutes` and `seconds`.
 ///
 /// This is the same as [`secs_to_hms`] except it will wrap around,
 /// e.g, `24:00:00` would turn into `00:00:00`.
 ///
 /// - The seconds returned is guaranteed to be `0..=59`
 /// - The minutes returned is guaranteed to be `0..=59`
 /// - The hours returned is guaranteed to be `0..=23`
 ///
 /// ```rust
 /// # use helper::time::*;
 /// // 59 seconds.
 /// assert_eq!(secs_to_clock(59), (0, 0, 59));
 ///
 /// // 1 minute.
 /// assert_eq!(secs_to_clock(60), (0, 1, 0));
 ///
 /// // 59 minutes, 59 seconds.
 /// assert_eq!(secs_to_clock(3599), (0, 59, 59));
 ///
 /// // 1 hour.
 /// assert_eq!(secs_to_clock(3600), (1, 0, 0));
 ///
 /// // 23 hours, 59 minutes, 59 seconds.
 /// assert_eq!(secs_to_clock(86399), (23, 59, 59));
 ///
 /// // 24 hours (wraps back)
 /// assert_eq!(secs_to_clock(86400), (0, 0, 0));
 ///
 /// // 24 hours, 59 minutes, 59 seconds (wraps back)
 /// assert_eq!(secs_to_clock(89999), (0, 59, 59));
 /// ```
 pub const fn secs_to_clock(seconds: u32) -> (u8, u8, u8) {
    let seconds = seconds % 86400;
    let (h, m, s) = secs_to_hms(seconds as u64);
    debug_assert!(h < 24);
    debug_assert!(m < 60);
    debug_assert!(s < 60);
    (h as u8, m, s)
 }
 #[inline]
 /// Get the current system time in the system's timezone
 ///
 /// The returned value is the total amount of seconds passed in the current day.
 ///
 /// This is guaranteed to return a value between `0..=86399`
 ///
 /// This will return `0` if the underlying system call fails.
 pub fn time() -> u32 {
    use chrono::Timelike;
    let now = chrono::offset::Local::now().time();
    (now.hour() * 3600) + (now.minute() * 60) + now.second()
 }
 #[inline]
 /// Get the current system time in the UTC timezone
 ///
 /// The returned value is the total amount of seconds passed in the current day.
 ///
 /// This is guaranteed to return a value between `0..=86399`
 pub fn time_utc() -> u32 {
    unix_clock(chrono::offset::Local::now().timestamp() as u64)
 }
 //---------------------------------------------------------------------------------------------------- Tests
 #[cfg(test)]
 mod test {}