thread_local-1.1.4/.cargo_vcs_info.json0000644000000001360000000000100134600ustar { "git": { "sha1": "4a54e5702e0968bdda77366738ba646f646044e8" }, "path_in_vcs": "" }thread_local-1.1.4/.gitignore000064400000000000000000000000220072674642500142620ustar 00000000000000target Cargo.lock thread_local-1.1.4/.travis.yml000064400000000000000000000011250072674642500144100ustar 00000000000000language: rust sudo: false rust: - nightly - beta - stable - 1.36.0 before_script: - | pip install 'travis-cargo<0.2' --user && export PATH=$HOME/.local/bin:$PATH script: - travis-cargo build - travis-cargo test - travis-cargo bench -- --features criterion # Criterion may drop support for 1.36.0 in the future. If it does, replace the above line with this: # - travis-cargo --skip 1.36.0 bench -- --features criterion - travis-cargo doc -- --no-deps after_success: - travis-cargo --only nightly doc-upload env: global: - TRAVIS_CARGO_NIGHTLY_FEATURE="" notifications: email: false thread_local-1.1.4/Cargo.toml0000644000000021170000000000100114570ustar # THIS FILE IS AUTOMATICALLY GENERATED BY CARGO # # When uploading crates to the registry Cargo will automatically # "normalize" Cargo.toml files for maximal compatibility # with all versions of Cargo and also rewrite `path` dependencies # to registry (e.g., crates.io) dependencies. # # If you are reading this file be aware that the original Cargo.toml # will likely look very different (and much more reasonable). # See Cargo.toml.orig for the original contents. [package] edition = "2018" name = "thread_local" version = "1.1.4" authors = ["Amanieu d'Antras "] description = "Per-object thread-local storage" documentation = "https://docs.rs/thread_local/" readme = "README.md" keywords = ["thread_local", "concurrent", "thread"] license = "Apache-2.0/MIT" repository = "https://github.com/Amanieu/thread_local-rs" [[bench]] name = "thread_local" harness = false required-features = ["criterion"] [dependencies.criterion] version = "0.3.3" optional = true [dependencies.once_cell] version = "1.5.2" [dev-dependencies] [badges.travis-ci] repository = "Amanieu/thread_local-rs" thread_local-1.1.4/Cargo.toml.orig000064400000000000000000000013140072674642500151660ustar 00000000000000[package] name = "thread_local" version = "1.1.4" authors = ["Amanieu d'Antras "] description = "Per-object thread-local storage" documentation = "https://docs.rs/thread_local/" license = "Apache-2.0/MIT" repository = "https://github.com/Amanieu/thread_local-rs" readme = "README.md" keywords = ["thread_local", "concurrent", "thread"] edition = "2018" [badges] travis-ci = { repository = "Amanieu/thread_local-rs" } [dependencies] once_cell = "1.5.2" # This is actually a dev-dependency, see https://github.com/rust-lang/cargo/issues/1596 criterion = { version = "0.3.3", optional = true } [dev-dependencies] [[bench]] name = "thread_local" required-features = ["criterion"] harness = false thread_local-1.1.4/LICENSE-APACHE000064400000000000000000000251370072674642500142340ustar 00000000000000 Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. 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See the License for the specific language governing permissions and limitations under the License. thread_local-1.1.4/LICENSE-MIT000064400000000000000000000020570072674642500137400ustar 00000000000000Copyright (c) 2016 The Rust Project Developers Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. thread_local-1.1.4/README.md000064400000000000000000000023420072674642500135600ustar 00000000000000thread_local ============ [![Build Status](https://travis-ci.org/Amanieu/thread_local-rs.svg?branch=master)](https://travis-ci.org/Amanieu/thread_local-rs) [![Crates.io](https://img.shields.io/crates/v/thread_local.svg)](https://crates.io/crates/thread_local) This library provides the `ThreadLocal` type which allow a separate copy of an object to be used for each thread. This allows for per-object thread-local storage, unlike the standard library's `thread_local!` macro which only allows static thread-local storage. [Documentation](https://docs.rs/thread_local/) ## Usage Add this to your `Cargo.toml`: ```toml [dependencies] thread_local = "1.1" ``` ## Minimum Rust version This crate's minimum supported Rust version (MSRV) is 1.36.0. ## License Licensed under either of * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0) * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT) at your option. ### Contribution Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions. thread_local-1.1.4/benches/thread_local.rs000064400000000000000000000011670072674642500167030ustar 00000000000000extern crate criterion; extern crate thread_local; use criterion::{black_box, BatchSize}; use thread_local::ThreadLocal; fn main() { let mut c = criterion::Criterion::default().configure_from_args(); c.bench_function("get", |b| { let local = ThreadLocal::new(); local.get_or(|| Box::new(0)); b.iter(|| { black_box(local.get()); }); }); c.bench_function("insert", |b| { b.iter_batched_ref( ThreadLocal::new, |local| { black_box(local.get_or(|| 0)); }, BatchSize::SmallInput, ) }); } thread_local-1.1.4/src/cached.rs000064400000000000000000000105430072674642500146470ustar 00000000000000#![allow(deprecated)] use super::{IntoIter, IterMut, ThreadLocal}; use std::fmt; use std::panic::UnwindSafe; use std::usize; /// Wrapper around [`ThreadLocal`]. /// /// This used to add a fast path for a single thread, however that has been /// obsoleted by performance improvements to [`ThreadLocal`] itself. #[deprecated(since = "1.1.0", note = "Use `ThreadLocal` instead")] pub struct CachedThreadLocal { inner: ThreadLocal, } impl Default for CachedThreadLocal { fn default() -> CachedThreadLocal { CachedThreadLocal::new() } } impl CachedThreadLocal { /// Creates a new empty `CachedThreadLocal`. #[inline] pub fn new() -> CachedThreadLocal { CachedThreadLocal { inner: ThreadLocal::new(), } } /// Returns the element for the current thread, if it exists. #[inline] pub fn get(&self) -> Option<&T> { self.inner.get() } /// Returns the element for the current thread, or creates it if it doesn't /// exist. #[inline] pub fn get_or(&self, create: F) -> &T where F: FnOnce() -> T, { self.inner.get_or(create) } /// Returns the element for the current thread, or creates it if it doesn't /// exist. If `create` fails, that error is returned and no element is /// added. #[inline] pub fn get_or_try(&self, create: F) -> Result<&T, E> where F: FnOnce() -> Result, { self.inner.get_or_try(create) } /// Returns a mutable iterator over the local values of all threads. /// /// Since this call borrows the `ThreadLocal` mutably, this operation can /// be done safely---the mutable borrow statically guarantees no other /// threads are currently accessing their associated values. #[inline] pub fn iter_mut(&mut self) -> CachedIterMut { CachedIterMut { inner: self.inner.iter_mut(), } } /// Removes all thread-specific values from the `ThreadLocal`, effectively /// reseting it to its original state. /// /// Since this call borrows the `ThreadLocal` mutably, this operation can /// be done safely---the mutable borrow statically guarantees no other /// threads are currently accessing their associated values. #[inline] pub fn clear(&mut self) { self.inner.clear(); } } impl IntoIterator for CachedThreadLocal { type Item = T; type IntoIter = CachedIntoIter; fn into_iter(self) -> CachedIntoIter { CachedIntoIter { inner: self.inner.into_iter(), } } } impl<'a, T: Send + 'a> IntoIterator for &'a mut CachedThreadLocal { type Item = &'a mut T; type IntoIter = CachedIterMut<'a, T>; fn into_iter(self) -> CachedIterMut<'a, T> { self.iter_mut() } } impl CachedThreadLocal { /// Returns the element for the current thread, or creates a default one if /// it doesn't exist. pub fn get_or_default(&self) -> &T { self.get_or(T::default) } } impl fmt::Debug for CachedThreadLocal { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "ThreadLocal {{ local_data: {:?} }}", self.get()) } } impl UnwindSafe for CachedThreadLocal {} /// Mutable iterator over the contents of a `CachedThreadLocal`. #[deprecated(since = "1.1.0", note = "Use `IterMut` instead")] pub struct CachedIterMut<'a, T: Send + 'a> { inner: IterMut<'a, T>, } impl<'a, T: Send + 'a> Iterator for CachedIterMut<'a, T> { type Item = &'a mut T; #[inline] fn next(&mut self) -> Option<&'a mut T> { self.inner.next() } #[inline] fn size_hint(&self) -> (usize, Option) { self.inner.size_hint() } } impl<'a, T: Send + 'a> ExactSizeIterator for CachedIterMut<'a, T> {} /// An iterator that moves out of a `CachedThreadLocal`. #[deprecated(since = "1.1.0", note = "Use `IntoIter` instead")] pub struct CachedIntoIter { inner: IntoIter, } impl Iterator for CachedIntoIter { type Item = T; #[inline] fn next(&mut self) -> Option { self.inner.next() } #[inline] fn size_hint(&self) -> (usize, Option) { self.inner.size_hint() } } impl ExactSizeIterator for CachedIntoIter {} thread_local-1.1.4/src/lib.rs000064400000000000000000000463150072674642500142140ustar 00000000000000// Copyright 2017 Amanieu d'Antras // // Licensed under the Apache License, Version 2.0, or the MIT license , at your option. This file may not be // copied, modified, or distributed except according to those terms. //! Per-object thread-local storage //! //! This library provides the `ThreadLocal` type which allows a separate copy of //! an object to be used for each thread. This allows for per-object //! thread-local storage, unlike the standard library's `thread_local!` macro //! which only allows static thread-local storage. //! //! Per-thread objects are not destroyed when a thread exits. Instead, objects //! are only destroyed when the `ThreadLocal` containing them is destroyed. //! //! You can also iterate over the thread-local values of all thread in a //! `ThreadLocal` object using the `iter_mut` and `into_iter` methods. This can //! only be done if you have mutable access to the `ThreadLocal` object, which //! guarantees that you are the only thread currently accessing it. //! //! Note that since thread IDs are recycled when a thread exits, it is possible //! for one thread to retrieve the object of another thread. Since this can only //! occur after a thread has exited this does not lead to any race conditions. //! //! # Examples //! //! Basic usage of `ThreadLocal`: //! //! ```rust //! use thread_local::ThreadLocal; //! let tls: ThreadLocal = ThreadLocal::new(); //! assert_eq!(tls.get(), None); //! assert_eq!(tls.get_or(|| 5), &5); //! assert_eq!(tls.get(), Some(&5)); //! ``` //! //! Combining thread-local values into a single result: //! //! ```rust //! use thread_local::ThreadLocal; //! use std::sync::Arc; //! use std::cell::Cell; //! use std::thread; //! //! let tls = Arc::new(ThreadLocal::new()); //! //! // Create a bunch of threads to do stuff //! for _ in 0..5 { //! let tls2 = tls.clone(); //! thread::spawn(move || { //! // Increment a counter to count some event... //! let cell = tls2.get_or(|| Cell::new(0)); //! cell.set(cell.get() + 1); //! }).join().unwrap(); //! } //! //! // Once all threads are done, collect the counter values and return the //! // sum of all thread-local counter values. //! let tls = Arc::try_unwrap(tls).unwrap(); //! let total = tls.into_iter().fold(0, |x, y| x + y.get()); //! assert_eq!(total, 5); //! ``` #![warn(missing_docs)] #![allow(clippy::mutex_atomic)] mod cached; mod thread_id; mod unreachable; #[allow(deprecated)] pub use cached::{CachedIntoIter, CachedIterMut, CachedThreadLocal}; use std::cell::UnsafeCell; use std::fmt; use std::iter::FusedIterator; use std::mem; use std::mem::MaybeUninit; use std::panic::UnwindSafe; use std::ptr; use std::sync::atomic::{AtomicBool, AtomicPtr, AtomicUsize, Ordering}; use std::sync::Mutex; use thread_id::Thread; use unreachable::UncheckedResultExt; // Use usize::BITS once it has stabilized and the MSRV has been bumped. #[cfg(target_pointer_width = "16")] const POINTER_WIDTH: u8 = 16; #[cfg(target_pointer_width = "32")] const POINTER_WIDTH: u8 = 32; #[cfg(target_pointer_width = "64")] const POINTER_WIDTH: u8 = 64; /// The total number of buckets stored in each thread local. const BUCKETS: usize = (POINTER_WIDTH + 1) as usize; /// Thread-local variable wrapper /// /// See the [module-level documentation](index.html) for more. pub struct ThreadLocal { /// The buckets in the thread local. The nth bucket contains `2^(n-1)` /// elements. Each bucket is lazily allocated. buckets: [AtomicPtr>; BUCKETS], /// The number of values in the thread local. This can be less than the real number of values, /// but is never more. values: AtomicUsize, /// Lock used to guard against concurrent modifications. This is taken when /// there is a possibility of allocating a new bucket, which only occurs /// when inserting values. lock: Mutex<()>, } struct Entry { present: AtomicBool, value: UnsafeCell>, } impl Drop for Entry { fn drop(&mut self) { unsafe { if *self.present.get_mut() { ptr::drop_in_place((*self.value.get()).as_mut_ptr()); } } } } // ThreadLocal is always Sync, even if T isn't unsafe impl Sync for ThreadLocal {} impl Default for ThreadLocal { fn default() -> ThreadLocal { ThreadLocal::new() } } impl Drop for ThreadLocal { fn drop(&mut self) { let mut bucket_size = 1; // Free each non-null bucket for (i, bucket) in self.buckets.iter_mut().enumerate() { let bucket_ptr = *bucket.get_mut(); let this_bucket_size = bucket_size; if i != 0 { bucket_size <<= 1; } if bucket_ptr.is_null() { continue; } unsafe { Box::from_raw(std::slice::from_raw_parts_mut(bucket_ptr, this_bucket_size)) }; } } } impl ThreadLocal { /// Creates a new empty `ThreadLocal`. pub fn new() -> ThreadLocal { Self::with_capacity(2) } /// Creates a new `ThreadLocal` with an initial capacity. If less than the capacity threads /// access the thread local it will never reallocate. The capacity may be rounded up to the /// nearest power of two. pub fn with_capacity(capacity: usize) -> ThreadLocal { let allocated_buckets = capacity .checked_sub(1) .map(|c| usize::from(POINTER_WIDTH) - (c.leading_zeros() as usize) + 1) .unwrap_or(0); let mut buckets = [ptr::null_mut(); BUCKETS]; let mut bucket_size = 1; for (i, bucket) in buckets[..allocated_buckets].iter_mut().enumerate() { *bucket = allocate_bucket::(bucket_size); if i != 0 { bucket_size <<= 1; } } ThreadLocal { // Safety: AtomicPtr has the same representation as a pointer and arrays have the same // representation as a sequence of their inner type. buckets: unsafe { mem::transmute(buckets) }, values: AtomicUsize::new(0), lock: Mutex::new(()), } } /// Returns the element for the current thread, if it exists. pub fn get(&self) -> Option<&T> { let thread = thread_id::get(); self.get_inner(thread) } /// Returns the element for the current thread, or creates it if it doesn't /// exist. pub fn get_or(&self, create: F) -> &T where F: FnOnce() -> T, { unsafe { self.get_or_try(|| Ok::(create())) .unchecked_unwrap_ok() } } /// Returns the element for the current thread, or creates it if it doesn't /// exist. If `create` fails, that error is returned and no element is /// added. pub fn get_or_try(&self, create: F) -> Result<&T, E> where F: FnOnce() -> Result, { let thread = thread_id::get(); match self.get_inner(thread) { Some(x) => Ok(x), None => Ok(self.insert(thread, create()?)), } } fn get_inner(&self, thread: Thread) -> Option<&T> { let bucket_ptr = unsafe { self.buckets.get_unchecked(thread.bucket) }.load(Ordering::Acquire); if bucket_ptr.is_null() { return None; } unsafe { let entry = &*bucket_ptr.add(thread.index); // Read without atomic operations as only this thread can set the value. if (&entry.present as *const _ as *const bool).read() { Some(&*(&*entry.value.get()).as_ptr()) } else { None } } } #[cold] fn insert(&self, thread: Thread, data: T) -> &T { // Lock the Mutex to ensure only a single thread is allocating buckets at once let _guard = self.lock.lock().unwrap(); let bucket_atomic_ptr = unsafe { self.buckets.get_unchecked(thread.bucket) }; let bucket_ptr: *const _ = bucket_atomic_ptr.load(Ordering::Acquire); let bucket_ptr = if bucket_ptr.is_null() { // Allocate a new bucket let bucket_ptr = allocate_bucket(thread.bucket_size); bucket_atomic_ptr.store(bucket_ptr, Ordering::Release); bucket_ptr } else { bucket_ptr }; drop(_guard); // Insert the new element into the bucket let entry = unsafe { &*bucket_ptr.add(thread.index) }; let value_ptr = entry.value.get(); unsafe { value_ptr.write(MaybeUninit::new(data)) }; entry.present.store(true, Ordering::Release); self.values.fetch_add(1, Ordering::Release); unsafe { &*(&*value_ptr).as_ptr() } } /// Returns an iterator over the local values of all threads in unspecified /// order. /// /// This call can be done safely, as `T` is required to implement [`Sync`]. pub fn iter(&self) -> Iter<'_, T> where T: Sync, { Iter { thread_local: self, raw: RawIter::new(), } } /// Returns a mutable iterator over the local values of all threads in /// unspecified order. /// /// Since this call borrows the `ThreadLocal` mutably, this operation can /// be done safely---the mutable borrow statically guarantees no other /// threads are currently accessing their associated values. pub fn iter_mut(&mut self) -> IterMut { IterMut { thread_local: self, raw: RawIter::new(), } } /// Removes all thread-specific values from the `ThreadLocal`, effectively /// reseting it to its original state. /// /// Since this call borrows the `ThreadLocal` mutably, this operation can /// be done safely---the mutable borrow statically guarantees no other /// threads are currently accessing their associated values. pub fn clear(&mut self) { *self = ThreadLocal::new(); } } impl IntoIterator for ThreadLocal { type Item = T; type IntoIter = IntoIter; fn into_iter(self) -> IntoIter { IntoIter { thread_local: self, raw: RawIter::new(), } } } impl<'a, T: Send + Sync> IntoIterator for &'a ThreadLocal { type Item = &'a T; type IntoIter = Iter<'a, T>; fn into_iter(self) -> Self::IntoIter { self.iter() } } impl<'a, T: Send> IntoIterator for &'a mut ThreadLocal { type Item = &'a mut T; type IntoIter = IterMut<'a, T>; fn into_iter(self) -> IterMut<'a, T> { self.iter_mut() } } impl ThreadLocal { /// Returns the element for the current thread, or creates a default one if /// it doesn't exist. pub fn get_or_default(&self) -> &T { self.get_or(Default::default) } } impl fmt::Debug for ThreadLocal { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "ThreadLocal {{ local_data: {:?} }}", self.get()) } } impl UnwindSafe for ThreadLocal {} #[derive(Debug)] struct RawIter { yielded: usize, bucket: usize, bucket_size: usize, index: usize, } impl RawIter { #[inline] fn new() -> Self { Self { yielded: 0, bucket: 0, bucket_size: 1, index: 0, } } fn next<'a, T: Send + Sync>(&mut self, thread_local: &'a ThreadLocal) -> Option<&'a T> { while self.bucket < BUCKETS { let bucket = unsafe { thread_local.buckets.get_unchecked(self.bucket) }; let bucket = bucket.load(Ordering::Acquire); if !bucket.is_null() { while self.index < self.bucket_size { let entry = unsafe { &*bucket.add(self.index) }; self.index += 1; if entry.present.load(Ordering::Acquire) { self.yielded += 1; return Some(unsafe { &*(&*entry.value.get()).as_ptr() }); } } } self.next_bucket(); } None } fn next_mut<'a, T: Send>( &mut self, thread_local: &'a mut ThreadLocal, ) -> Option<&'a mut Entry> { if *thread_local.values.get_mut() == self.yielded { return None; } loop { let bucket = unsafe { thread_local.buckets.get_unchecked_mut(self.bucket) }; let bucket = *bucket.get_mut(); if !bucket.is_null() { while self.index < self.bucket_size { let entry = unsafe { &mut *bucket.add(self.index) }; self.index += 1; if *entry.present.get_mut() { self.yielded += 1; return Some(entry); } } } self.next_bucket(); } } #[inline] fn next_bucket(&mut self) { if self.bucket != 0 { self.bucket_size <<= 1; } self.bucket += 1; self.index = 0; } fn size_hint(&self, thread_local: &ThreadLocal) -> (usize, Option) { let total = thread_local.values.load(Ordering::Acquire); (total - self.yielded, None) } fn size_hint_frozen(&self, thread_local: &ThreadLocal) -> (usize, Option) { let total = unsafe { *(&thread_local.values as *const AtomicUsize as *const usize) }; let remaining = total - self.yielded; (remaining, Some(remaining)) } } /// Iterator over the contents of a `ThreadLocal`. #[derive(Debug)] pub struct Iter<'a, T: Send + Sync> { thread_local: &'a ThreadLocal, raw: RawIter, } impl<'a, T: Send + Sync> Iterator for Iter<'a, T> { type Item = &'a T; fn next(&mut self) -> Option { self.raw.next(self.thread_local) } fn size_hint(&self) -> (usize, Option) { self.raw.size_hint(self.thread_local) } } impl FusedIterator for Iter<'_, T> {} /// Mutable iterator over the contents of a `ThreadLocal`. pub struct IterMut<'a, T: Send> { thread_local: &'a mut ThreadLocal, raw: RawIter, } impl<'a, T: Send> Iterator for IterMut<'a, T> { type Item = &'a mut T; fn next(&mut self) -> Option<&'a mut T> { self.raw .next_mut(self.thread_local) .map(|entry| unsafe { &mut *(&mut *entry.value.get()).as_mut_ptr() }) } fn size_hint(&self) -> (usize, Option) { self.raw.size_hint_frozen(self.thread_local) } } impl ExactSizeIterator for IterMut<'_, T> {} impl FusedIterator for IterMut<'_, T> {} // Manual impl so we don't call Debug on the ThreadLocal, as doing so would create a reference to // this thread's value that potentially aliases with a mutable reference we have given out. impl<'a, T: Send + fmt::Debug> fmt::Debug for IterMut<'a, T> { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { f.debug_struct("IterMut").field("raw", &self.raw).finish() } } /// An iterator that moves out of a `ThreadLocal`. #[derive(Debug)] pub struct IntoIter { thread_local: ThreadLocal, raw: RawIter, } impl Iterator for IntoIter { type Item = T; fn next(&mut self) -> Option { self.raw.next_mut(&mut self.thread_local).map(|entry| { *entry.present.get_mut() = false; unsafe { std::mem::replace(&mut *entry.value.get(), MaybeUninit::uninit()).assume_init() } }) } fn size_hint(&self) -> (usize, Option) { self.raw.size_hint_frozen(&self.thread_local) } } impl ExactSizeIterator for IntoIter {} impl FusedIterator for IntoIter {} fn allocate_bucket(size: usize) -> *mut Entry { Box::into_raw( (0..size) .map(|_| Entry:: { present: AtomicBool::new(false), value: UnsafeCell::new(MaybeUninit::uninit()), }) .collect(), ) as *mut _ } #[cfg(test)] mod tests { use super::ThreadLocal; use std::cell::RefCell; use std::sync::atomic::AtomicUsize; use std::sync::atomic::Ordering::Relaxed; use std::sync::Arc; use std::thread; fn make_create() -> Arc usize + Send + Sync> { let count = AtomicUsize::new(0); Arc::new(move || count.fetch_add(1, Relaxed)) } #[test] fn same_thread() { let create = make_create(); let mut tls = ThreadLocal::new(); assert_eq!(None, tls.get()); assert_eq!("ThreadLocal { local_data: None }", format!("{:?}", &tls)); assert_eq!(0, *tls.get_or(|| create())); assert_eq!(Some(&0), tls.get()); assert_eq!(0, *tls.get_or(|| create())); assert_eq!(Some(&0), tls.get()); assert_eq!(0, *tls.get_or(|| create())); assert_eq!(Some(&0), tls.get()); assert_eq!("ThreadLocal { local_data: Some(0) }", format!("{:?}", &tls)); tls.clear(); assert_eq!(None, tls.get()); } #[test] fn different_thread() { let create = make_create(); let tls = Arc::new(ThreadLocal::new()); assert_eq!(None, tls.get()); assert_eq!(0, *tls.get_or(|| create())); assert_eq!(Some(&0), tls.get()); let tls2 = tls.clone(); let create2 = create.clone(); thread::spawn(move || { assert_eq!(None, tls2.get()); assert_eq!(1, *tls2.get_or(|| create2())); assert_eq!(Some(&1), tls2.get()); }) .join() .unwrap(); assert_eq!(Some(&0), tls.get()); assert_eq!(0, *tls.get_or(|| create())); } #[test] fn iter() { let tls = Arc::new(ThreadLocal::new()); tls.get_or(|| Box::new(1)); let tls2 = tls.clone(); thread::spawn(move || { tls2.get_or(|| Box::new(2)); let tls3 = tls2.clone(); thread::spawn(move || { tls3.get_or(|| Box::new(3)); }) .join() .unwrap(); drop(tls2); }) .join() .unwrap(); let mut tls = Arc::try_unwrap(tls).unwrap(); let mut v = tls.iter().map(|x| **x).collect::>(); v.sort_unstable(); assert_eq!(vec![1, 2, 3], v); let mut v = tls.iter_mut().map(|x| **x).collect::>(); v.sort_unstable(); assert_eq!(vec![1, 2, 3], v); let mut v = tls.into_iter().map(|x| *x).collect::>(); v.sort_unstable(); assert_eq!(vec![1, 2, 3], v); } #[test] fn test_drop() { let local = ThreadLocal::new(); struct Dropped(Arc); impl Drop for Dropped { fn drop(&mut self) { self.0.fetch_add(1, Relaxed); } } let dropped = Arc::new(AtomicUsize::new(0)); local.get_or(|| Dropped(dropped.clone())); assert_eq!(dropped.load(Relaxed), 0); drop(local); assert_eq!(dropped.load(Relaxed), 1); } #[test] fn is_sync() { fn foo() {} foo::>(); foo::>>(); } } thread_local-1.1.4/src/thread_id.rs000064400000000000000000000073460072674642500153720ustar 00000000000000// Copyright 2017 Amanieu d'Antras // // Licensed under the Apache License, Version 2.0, or the MIT license , at your option. This file may not be // copied, modified, or distributed except according to those terms. use crate::POINTER_WIDTH; use once_cell::sync::Lazy; use std::cmp::Reverse; use std::collections::BinaryHeap; use std::sync::Mutex; use std::usize; /// Thread ID manager which allocates thread IDs. It attempts to aggressively /// reuse thread IDs where possible to avoid cases where a ThreadLocal grows /// indefinitely when it is used by many short-lived threads. struct ThreadIdManager { free_from: usize, free_list: BinaryHeap>, } impl ThreadIdManager { fn new() -> ThreadIdManager { ThreadIdManager { free_from: 0, free_list: BinaryHeap::new(), } } fn alloc(&mut self) -> usize { if let Some(id) = self.free_list.pop() { id.0 } else { let id = self.free_from; self.free_from = self .free_from .checked_add(1) .expect("Ran out of thread IDs"); id } } fn free(&mut self, id: usize) { self.free_list.push(Reverse(id)); } } static THREAD_ID_MANAGER: Lazy> = Lazy::new(|| Mutex::new(ThreadIdManager::new())); /// Data which is unique to the current thread while it is running. /// A thread ID may be reused after a thread exits. #[derive(Clone, Copy)] pub(crate) struct Thread { /// The thread ID obtained from the thread ID manager. pub(crate) id: usize, /// The bucket this thread's local storage will be in. pub(crate) bucket: usize, /// The size of the bucket this thread's local storage will be in. pub(crate) bucket_size: usize, /// The index into the bucket this thread's local storage is in. pub(crate) index: usize, } impl Thread { fn new(id: usize) -> Thread { let bucket = usize::from(POINTER_WIDTH) - id.leading_zeros() as usize; let bucket_size = 1 << bucket.saturating_sub(1); let index = if id != 0 { id ^ bucket_size } else { 0 }; Thread { id, bucket, bucket_size, index, } } } /// Wrapper around `Thread` that allocates and deallocates the ID. struct ThreadHolder(Thread); impl ThreadHolder { fn new() -> ThreadHolder { ThreadHolder(Thread::new(THREAD_ID_MANAGER.lock().unwrap().alloc())) } } impl Drop for ThreadHolder { fn drop(&mut self) { THREAD_ID_MANAGER.lock().unwrap().free(self.0.id); } } thread_local!(static THREAD_HOLDER: ThreadHolder = ThreadHolder::new()); /// Get the current thread. pub(crate) fn get() -> Thread { THREAD_HOLDER.with(|holder| holder.0) } #[test] fn test_thread() { let thread = Thread::new(0); assert_eq!(thread.id, 0); assert_eq!(thread.bucket, 0); assert_eq!(thread.bucket_size, 1); assert_eq!(thread.index, 0); let thread = Thread::new(1); assert_eq!(thread.id, 1); assert_eq!(thread.bucket, 1); assert_eq!(thread.bucket_size, 1); assert_eq!(thread.index, 0); let thread = Thread::new(2); assert_eq!(thread.id, 2); assert_eq!(thread.bucket, 2); assert_eq!(thread.bucket_size, 2); assert_eq!(thread.index, 0); let thread = Thread::new(3); assert_eq!(thread.id, 3); assert_eq!(thread.bucket, 2); assert_eq!(thread.bucket_size, 2); assert_eq!(thread.index, 1); let thread = Thread::new(19); assert_eq!(thread.id, 19); assert_eq!(thread.bucket, 5); assert_eq!(thread.bucket_size, 16); assert_eq!(thread.index, 3); } thread_local-1.1.4/src/unreachable.rs000064400000000000000000000033230072674642500157070ustar 00000000000000// Copyright 2017 Amanieu d'Antras // // Licensed under the Apache License, Version 2.0, or the MIT license , at your option. This file may not be // copied, modified, or distributed except according to those terms. use std::hint::unreachable_unchecked; /// An extension trait for `Option` providing unchecked unwrapping methods. pub trait UncheckedOptionExt { /// Get the value out of this Option without checking for None. unsafe fn unchecked_unwrap(self) -> T; /// Assert that this Option is a None to the optimizer. unsafe fn unchecked_unwrap_none(self); } /// An extension trait for `Result` providing unchecked unwrapping methods. pub trait UncheckedResultExt { /// Get the value out of this Result without checking for Err. unsafe fn unchecked_unwrap_ok(self) -> T; /// Get the error out of this Result without checking for Ok. unsafe fn unchecked_unwrap_err(self) -> E; } impl UncheckedOptionExt for Option { unsafe fn unchecked_unwrap(self) -> T { match self { Some(x) => x, None => unreachable_unchecked(), } } unsafe fn unchecked_unwrap_none(self) { if self.is_some() { unreachable_unchecked() } } } impl UncheckedResultExt for Result { unsafe fn unchecked_unwrap_ok(self) -> T { match self { Ok(x) => x, Err(_) => unreachable_unchecked(), } } unsafe fn unchecked_unwrap_err(self) -> E { match self { Ok(_) => unreachable_unchecked(), Err(e) => e, } } }