build(rust): vendor rnix parser crate

third_party/crates/countme-3.0.1/src/imp.rs

@@ -0,0 +1,175 @@
+use std::{
+    any::{type_name, TypeId},
+    cell::RefCell,
+    collections::HashMap,
+    hash::BuildHasherDefault,
+    os::raw::c_int,
+    sync::atomic::{AtomicBool, AtomicUsize, Ordering::Relaxed},
+    sync::Arc,
+};
+
+use dashmap::DashMap;
+use once_cell::sync::OnceCell;
+use rustc_hash::FxHasher;
+
+use crate::{AllCounts, Counts};
+
+static ENABLE: AtomicBool = AtomicBool::new(cfg!(feature = "print_at_exit"));
+
+type GlobalStore = DashMap<TypeId, Arc<Store>, BuildHasherDefault<FxHasher>>;
+
+#[inline]
+fn global_store() -> &'static GlobalStore {
+    static MAP: OnceCell<GlobalStore> = OnceCell::new();
+    MAP.get_or_init(|| {
+        if cfg!(feature = "print_at_exit") {
+            extern "C" {
+                fn atexit(f: extern "C" fn()) -> c_int;
+            }
+            extern "C" fn print_at_exit() {
+                eprint!("{}", get_all());
+            }
+            unsafe {
+                atexit(print_at_exit);
+            }
+        }
+
+        GlobalStore::default()
+    })
+}
+
+thread_local! {
+    static LOCAL: RefCell<HashMap<TypeId, Arc<Store>, BuildHasherDefault<FxHasher>>> = RefCell::default();
+}
+
+pub(crate) fn enable(yes: bool) {
+    ENABLE.store(yes, Relaxed);
+}
+
+#[inline]
+fn enabled() -> bool {
+    ENABLE.load(Relaxed)
+}
+
+#[inline]
+pub(crate) fn dec<T: 'static>() {
+    if enabled() {
+        do_dec(TypeId::of::<T>())
+    }
+}
+#[inline(never)]
+fn do_dec(key: TypeId) {
+    LOCAL.with(|local| {
+        // Fast path: we have needed store in thread local map
+        if let Some(store) = local.borrow().get(&key) {
+            store.dec();
+            return;
+        }
+
+        let global = global_store();
+
+        // Slightly slower: we don't have needed store in our thread local map,
+        // but some other thread has already initialized the needed store in the global map
+        if let Some(store) = global.get(&key) {
+            let store = store.value();
+            local.borrow_mut().insert(key, Arc::clone(store));
+            store.inc();
+            return;
+        }
+
+        // We only decrement counter after incremenrting it, so this line is unreachable
+    })
+}
+
+#[inline]
+pub(crate) fn inc<T: 'static>() {
+    if enabled() {
+        do_inc(TypeId::of::<T>(), type_name::<T>())
+    }
+}
+#[inline(never)]
+fn do_inc(key: TypeId, name: &'static str) {
+    LOCAL.with(|local| {
+        // Fast path: we have needed store in thread local map
+        if let Some(store) = local.borrow().get(&key) {
+            store.inc();
+            return;
+        }
+
+        let global = global_store();
+
+        let copy = match global.get(&key) {
+            // Slightly slower path: we don't have needed store in our thread local map,
+            // but some other thread has already initialized the needed store in the global map
+            Some(store) => {
+                let store = store.value();
+                store.inc();
+                Arc::clone(store)
+            }
+            // Slow path: we are the first to initialize both global and local maps
+            None => {
+                let store = global
+                    .entry(key)
+                    .or_insert_with(|| Arc::new(Store { name, ..Store::default() }))
+                    .downgrade();
+                let store = store.value();
+
+                store.inc();
+                Arc::clone(store)
+            }
+        };
+
+        local.borrow_mut().insert(key, copy);
+    });
+}
+
+pub(crate) fn get<T: 'static>() -> Counts {
+    do_get(TypeId::of::<T>())
+}
+fn do_get(key: TypeId) -> Counts {
+    global_store().entry(key).or_default().value().read()
+}
+
+pub(crate) fn get_all() -> AllCounts {
+    let mut entries = global_store()
+        .iter()
+        .map(|entry| {
+            let store = entry.value();
+            (store.type_name(), store.read())
+        })
+        .collect::<Vec<_>>();
+    entries.sort_by_key(|(name, _counts)| *name);
+    AllCounts { entries }
+}
+
+#[derive(Default)]
+struct Store {
+    total: AtomicUsize,
+    max_live: AtomicUsize,
+    live: AtomicUsize,
+    name: &'static str,
+}
+
+impl Store {
+    fn inc(&self) {
+        self.total.fetch_add(1, Relaxed);
+        let live = self.live.fetch_add(1, Relaxed) + 1;
+        self.max_live.fetch_max(live, Relaxed);
+    }
+
+    fn dec(&self) {
+        self.live.fetch_sub(1, Relaxed);
+    }
+
+    fn read(&self) -> Counts {
+        Counts {
+            total: self.total.load(Relaxed),
+            max_live: self.max_live.load(Relaxed),
+            live: self.live.load(Relaxed),
+        }
+    }
+
+    fn type_name(&self) -> &'static str {
+        self.name
+    }
+}

third_party/crates/countme-3.0.1/src/lib.rs

@@ -0,0 +1,193 @@
+//! A library to quickly get the live/total/max counts of allocated instances.
+//!
+//! # Example
+//!
+//! ```
+//! # if cfg!(not(feature = "enable")) { return; }
+//!
+//! #[derive(Default)]
+//! struct Widget {
+//!   _c: countme::Count<Self>,
+//! }
+//!
+//! countme::enable(true);
+//!
+//! let w1 = Widget::default();
+//! let w2 = Widget::default();
+//! let w3 = Widget::default();
+//! drop(w1);
+//!
+//! let counts = countme::get::<Widget>();
+//! assert_eq!(counts.live, 2);
+//! assert_eq!(counts.max_live, 3);
+//! assert_eq!(counts.total, 3);
+//!
+//! eprintln!("{}", countme::get_all());
+//! ```
+//!
+//! # Configuration
+//!
+//! By default, the implementation compiles to no-ops. Therefore it is possible
+//! to include `Count` fields into library types.
+//!
+//! The `enable` cargo feature ungates the counting code. The feature can be
+//! enabled anywhere in the crate graph.
+//!
+//! At run-time, the counters are controlled with [`enable`] function. Counting
+//! is enabled by default if `print_at_exit` feature is enabled. Otherwise
+//! counting is disabled by default. Call `enable(true)` early in `main` to enable:
+//!
+//! ```rust
+//! fn main() {
+//!     countme::enable(std::env::var("COUNTME").is_ok());
+//! }
+//! ```
+//!
+//! The code is optimized for the case where counting is not enabled at runtime
+//! (counting is a relaxed load and a branch to a function call).
+//!
+//! The `print_at_exit` Cargo feature uses `atexit` call to print final counts
+//! before the program exits (it also enables counting at runtime). Use it only
+//! when you can't modify the main to print counts -- `atexit` is not guaranteed
+//! to work with rust's runtime.
+#[cfg(feature = "enable")]
+mod imp;
+
+use std::{fmt, marker::PhantomData};
+
+#[derive(Debug, Clone, PartialEq, Eq, Default)]
+#[non_exhaustive]
+pub struct Counts {
+    /// The total number of tokens created.
+    pub total: usize,
+    /// The historical maximum of the `live` count.
+    pub max_live: usize,
+    /// The number of tokens which were created, but are not destroyed yet.
+    pub live: usize,
+}
+
+/// Store this inside your struct as `_c: countme::Count<Self>`.
+#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct Count<T: 'static> {
+    ghost: PhantomData<fn(T)>,
+}
+
+impl<T: 'static> Default for Count<T> {
+    #[inline]
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl<T: 'static> Clone for Count<T> {
+    #[inline]
+    fn clone(&self) -> Self {
+        Self::new()
+    }
+}
+
+impl<T: 'static> Count<T> {
+    /// Create new `Count`, incrementing the corresponding count.
+    #[inline]
+    pub fn new() -> Count<T> {
+        #[cfg(feature = "enable")]
+        imp::inc::<T>();
+        Count { ghost: PhantomData }
+    }
+}
+
+impl<T: 'static> Drop for Count<T> {
+    #[inline]
+    fn drop(&mut self) {
+        #[cfg(feature = "enable")]
+        imp::dec::<T>();
+    }
+}
+
+/// Enable or disable counting at runtime.
+///
+/// Counting is enabled by default if `print_at_exit` feature is enabled.
+/// Otherwise counting is disabled by default.
+///
+/// If neither `enable` nor `print_at_exit` features are enabled, then this function is noop.
+pub fn enable(_yes: bool) {
+    #[cfg(feature = "enable")]
+    imp::enable(_yes);
+}
+
+/// Returns the counts for the `T` type.
+#[inline]
+pub fn get<T: 'static>() -> Counts {
+    #[cfg(feature = "enable")]
+    {
+        return imp::get::<T>();
+    }
+    #[cfg(not(feature = "enable"))]
+    {
+        return Counts::default();
+    }
+}
+
+/// Returns a collection of counts for all types.
+pub fn get_all() -> AllCounts {
+    #[cfg(feature = "enable")]
+    {
+        return imp::get_all();
+    }
+    #[cfg(not(feature = "enable"))]
+    {
+        return AllCounts::default();
+    }
+}
+
+/// A collection of counts for all types.
+#[derive(Default, Clone, Debug)]
+pub struct AllCounts {
+    entries: Vec<(&'static str, Counts)>,
+}
+
+impl fmt::Display for AllCounts {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fn sep(mut n: usize) -> String {
+            let mut groups = Vec::new();
+            while n >= 1000 {
+                groups.push(format!("{:03}", n % 1000));
+                n /= 1000;
+            }
+            groups.push(n.to_string());
+            groups.reverse();
+            groups.join("_")
+        }
+
+        if self.entries.is_empty() {
+            return if cfg!(feature = "enable") {
+                writeln!(f, "all counts are zero")
+            } else {
+                writeln!(f, "counts are disabled")
+            };
+        }
+        let max_width =
+            self.entries.iter().map(|(name, _count)| name.chars().count()).max().unwrap_or(0);
+        for (name, counts) in &self.entries {
+            writeln!(
+                f,
+                "{:<max_width$}  {:>12} {:>12} {:>12}",
+                name,
+                sep(counts.total),
+                sep(counts.max_live),
+                sep(counts.live),
+                max_width = max_width
+            )?;
+        }
+        writeln!(
+            f,
+            "{:<max_width$}  {:>12} {:>12} {:>12}",
+            "",
+            "total",
+            "max_live",
+            "live",
+            max_width = max_width
+        )?;
+        Ok(())
+    }
+}