thread_local-0.3.6/.gitignore010064400017500001750000000000221270153207600143470ustar0000000000000000target Cargo.lock thread_local-0.3.6/.travis.yml010064400017500001750000000006341333506773400145110ustar0000000000000000language: rust sudo: false rust: - nightly - beta - stable - 1.21.0 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 - travis-cargo doc -- --no-deps after_success: - travis-cargo --only nightly doc-upload env: global: - TRAVIS_CARGO_NIGHTLY_FEATURE="" notifications: email: false thread_local-0.3.6/Cargo.toml.orig010064400017500001750000000007541333506774100152700ustar0000000000000000[package] name = "thread_local" version = "0.3.6" authors = ["Amanieu d'Antras "] description = "Per-object thread-local storage" documentation = "https://amanieu.github.io/thread_local-rs/thread_local/index.html" license = "Apache-2.0/MIT" repository = "https://github.com/Amanieu/thread_local-rs" readme = "README.md" keywords = ["thread_local", "concurrent", "thread"] [badges] travis-ci = { repository = "Amanieu/thread_local-rs" } [dependencies] lazy_static = "1.0" thread_local-0.3.6/Cargo.toml0000644000000017700000000000000115250ustar00# 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 believe there's an error in this file please file an # issue against the rust-lang/cargo repository. 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See the License for the specific language governing permissions and limitations under the License. thread_local-0.3.6/LICENSE-MIT010064400017500001750000000020571270165457200140330ustar0000000000000000Copyright (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-0.3.6/README.md010064400017500001750000000024151303065247200136450ustar0000000000000000thread_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` and `CachedThreadLocal` types 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://amanieu.github.io/thread_local-rs/thread_local/index.html) ## Usage Add this to your `Cargo.toml`: ```toml [dependencies] thread_local = "0.3" ``` and this to your crate root: ```rust extern crate thread_local; ``` ## 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-0.3.6/benches/thread_local.rs010064400017500001750000000006651312432152700167670ustar0000000000000000#![feature(test)] extern crate thread_local; extern crate test; use thread_local::{ThreadLocal, CachedThreadLocal}; #[bench] fn thread_local(b: &mut test::Bencher) { let local = ThreadLocal::new(); b.iter(|| { let _: &i32 = local.get_or(|| Box::new(0)); }); } #[bench] fn cached_thread_local(b: &mut test::Bencher) { let local = CachedThreadLocal::new(); b.iter(|| { let _: &i32 = local.get_or(|| Box::new(0)); }); } thread_local-0.3.6/src/lib.rs010064400017500001750000000603221333506773400143030ustar0000000000000000// 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. //! //! A `CachedThreadLocal` type is also provided which wraps a `ThreadLocal` but //! also uses a special fast path for the first thread that writes into it. The //! fast path has very low overhead (<1ns per access) while keeping the same //! performance as `ThreadLocal` for other threads. //! //! 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(|| Box::new(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(|| Box::new(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)] #[macro_use] extern crate lazy_static; mod thread_id; mod unreachable; use std::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; use std::sync::Mutex; use std::marker::PhantomData; use std::cell::UnsafeCell; use std::fmt; use std::iter::Chain; use std::option::IntoIter as OptionIter; use std::panic::UnwindSafe; use unreachable::{UncheckedOptionExt, UncheckedResultExt}; /// Thread-local variable wrapper /// /// See the [module-level documentation](index.html) for more. pub struct ThreadLocal { // Pointer to the current top-level hash table table: AtomicPtr>, // Lock used to guard against concurrent modifications. This is only taken // while writing to the table, not when reading from it. This also guards // the counter for the total number of values in the hash table. lock: Mutex, // PhantomData to indicate that we logically own T marker: PhantomData, } struct Table { // Hash entries for the table entries: Box<[TableEntry]>, // Number of bits used for the hash function hash_bits: usize, // Previous table, half the size of the current one prev: Option>>, } struct TableEntry { // Current owner of this entry, or 0 if this is an empty entry owner: AtomicUsize, // The object associated with this entry. This is only ever accessed by the // owner of the entry. data: UnsafeCell>>, } // 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) { unsafe { Box::from_raw(self.table.load(Ordering::Relaxed)); } } } // Implementation of Clone for TableEntry, needed to make vec![] work impl Clone for TableEntry { fn clone(&self) -> TableEntry { TableEntry { owner: AtomicUsize::new(0), data: UnsafeCell::new(None), } } } // Hash function for the thread id #[cfg(target_pointer_width = "32")] #[inline] fn hash(id: usize, bits: usize) -> usize { id.wrapping_mul(0x9E3779B9) >> (32 - bits) } #[cfg(target_pointer_width = "64")] #[inline] fn hash(id: usize, bits: usize) -> usize { id.wrapping_mul(0x9E37_79B9_7F4A_7C15) >> (64 - bits) } impl ThreadLocal { /// Creates a new empty `ThreadLocal`. pub fn new() -> ThreadLocal { let entry = TableEntry { owner: AtomicUsize::new(0), data: UnsafeCell::new(None), }; let table = Table { entries: vec![entry; 2].into_boxed_slice(), hash_bits: 1, prev: None, }; ThreadLocal { table: AtomicPtr::new(Box::into_raw(Box::new(table))), lock: Mutex::new(0), marker: PhantomData, } } /// Returns the element for the current thread, if it exists. pub fn get(&self) -> Option<&T> { let id = thread_id::get(); self.get_fast(id) } /// 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() -> Box, { 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, E>, { let id = thread_id::get(); match self.get_fast(id) { Some(x) => Ok(x), None => Ok(self.insert(id, try!(create()), true)), } } // Simple hash table lookup function fn lookup(id: usize, table: &Table) -> Option<&UnsafeCell>>> { // Because we use a Mutex to prevent concurrent modifications (but not // reads) of the hash table, we can avoid any memory barriers here. No // elements between our hash bucket and our value can have been modified // since we inserted our thread-local value into the table. for entry in table.entries.iter().cycle().skip(hash(id, table.hash_bits)) { let owner = entry.owner.load(Ordering::Relaxed); if owner == id { return Some(&entry.data); } if owner == 0 { return None; } } unreachable!(); } // Fast path: try to find our thread in the top-level hash table fn get_fast(&self, id: usize) -> Option<&T> { let table = unsafe { &*self.table.load(Ordering::Relaxed) }; match Self::lookup(id, table) { Some(x) => unsafe { Some((*x.get()).as_ref().unchecked_unwrap()) }, None => self.get_slow(id, table), } } // Slow path: try to find our thread in the other hash tables, and then // move it to the top-level hash table. #[cold] fn get_slow(&self, id: usize, table_top: &Table) -> Option<&T> { let mut current = &table_top.prev; while let Some(ref table) = *current { if let Some(x) = Self::lookup(id, table) { let data = unsafe { (*x.get()).take().unchecked_unwrap() }; return Some(self.insert(id, data, false)); } current = &table.prev; } None } #[cold] fn insert(&self, id: usize, data: Box, new: bool) -> &T { // Lock the Mutex to ensure only a single thread is modify the hash // table at once. let mut count = self.lock.lock().unwrap(); if new { *count += 1; } let table_raw = self.table.load(Ordering::Relaxed); let table = unsafe { &*table_raw }; // If the current top-level hash table is more than 75% full, add a new // level with 2x the capacity. Elements will be moved up to the new top // level table as they are accessed. let table = if *count > table.entries.len() * 3 / 4 { let entry = TableEntry { owner: AtomicUsize::new(0), data: UnsafeCell::new(None), }; let new_table = Box::into_raw(Box::new(Table { entries: vec![entry; table.entries.len() * 2].into_boxed_slice(), hash_bits: table.hash_bits + 1, prev: unsafe { Some(Box::from_raw(table_raw)) }, })); self.table.store(new_table, Ordering::Release); unsafe { &*new_table } } else { table }; // Insert the new element into the top-level hash table for entry in table.entries.iter().cycle().skip(hash(id, table.hash_bits)) { let owner = entry.owner.load(Ordering::Relaxed); if owner == 0 { unsafe { entry.owner.store(id, Ordering::Relaxed); *entry.data.get() = Some(data); return (*entry.data.get()).as_ref().unchecked_unwrap(); } } if owner == id { // This can happen if create() inserted a value into this // ThreadLocal between our calls to get_fast() and insert(). We // just return the existing value and drop the newly-allocated // Box. unsafe { return (*entry.data.get()).as_ref().unchecked_unwrap(); } } } unreachable!(); } /// 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. pub fn iter_mut(&mut self) -> IterMut { let raw = RawIter { remaining: *self.lock.lock().unwrap(), index: 0, table: self.table.load(Ordering::Relaxed), }; IterMut { raw: raw, marker: PhantomData, } } /// 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 = Box; type IntoIter = IntoIter; fn into_iter(self) -> IntoIter { let raw = RawIter { remaining: *self.lock.lock().unwrap(), index: 0, table: self.table.load(Ordering::Relaxed), }; IntoIter { raw: raw, _thread_local: self, } } } impl<'a, T: ?Sized + Send + 'a> IntoIterator for &'a mut ThreadLocal { type Item = &'a mut Box; 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_default(&self) -> &T { self.get_or(|| Box::new(T::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 {} struct RawIter { remaining: usize, index: usize, table: *const Table, } impl RawIter { fn next(&mut self) -> Option<*mut Option>> { if self.remaining == 0 { return None; } loop { let entries = unsafe { &(*self.table).entries[..] }; while self.index < entries.len() { let val = entries[self.index].data.get(); self.index += 1; if unsafe { (*val).is_some() } { self.remaining -= 1; return Some(val); } } self.index = 0; self.table = unsafe { &**(*self.table).prev.as_ref().unchecked_unwrap() }; } } } /// Mutable iterator over the contents of a `ThreadLocal`. pub struct IterMut<'a, T: ?Sized + Send + 'a> { raw: RawIter, marker: PhantomData<&'a mut ThreadLocal>, } impl<'a, T: ?Sized + Send + 'a> Iterator for IterMut<'a, T> { type Item = &'a mut Box; fn next(&mut self) -> Option<&'a mut Box> { self.raw.next().map(|x| unsafe { (*x).as_mut().unchecked_unwrap() }) } fn size_hint(&self) -> (usize, Option) { (self.raw.remaining, Some(self.raw.remaining)) } } impl<'a, T: ?Sized + Send + 'a> ExactSizeIterator for IterMut<'a, T> {} /// An iterator that moves out of a `ThreadLocal`. pub struct IntoIter { raw: RawIter, _thread_local: ThreadLocal, } impl Iterator for IntoIter { type Item = Box; fn next(&mut self) -> Option> { self.raw.next().map( |x| unsafe { (*x).take().unchecked_unwrap() }, ) } fn size_hint(&self) -> (usize, Option) { (self.raw.remaining, Some(self.raw.remaining)) } } impl ExactSizeIterator for IntoIter {} /// Wrapper around `ThreadLocal` which adds a fast path for a single thread. /// /// This has the same API as `ThreadLocal`, but will register the first thread /// that sets a value as its owner. All accesses by the owner will go through /// a special fast path which is much faster than the normal `ThreadLocal` path. pub struct CachedThreadLocal { owner: AtomicUsize, local: UnsafeCell>>, global: ThreadLocal, } // CachedThreadLocal is always Sync, even if T isn't unsafe impl Sync for CachedThreadLocal {} impl Default for CachedThreadLocal { fn default() -> CachedThreadLocal { CachedThreadLocal::new() } } impl CachedThreadLocal { /// Creates a new empty `CachedThreadLocal`. pub fn new() -> CachedThreadLocal { CachedThreadLocal { owner: AtomicUsize::new(0), local: UnsafeCell::new(None), global: ThreadLocal::new(), } } /// Returns the element for the current thread, if it exists. pub fn get(&self) -> Option<&T> { let id = thread_id::get(); let owner = self.owner.load(Ordering::Relaxed); if owner == id { return unsafe { Some((*self.local.get()).as_ref().unchecked_unwrap()) }; } if owner == 0 { return None; } self.global.get_fast(id) } /// Returns the element for the current thread, or creates it if it doesn't /// exist. #[inline(always)] pub fn get_or(&self, create: F) -> &T where F: FnOnce() -> Box, { 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, E>, { let id = thread_id::get(); let owner = self.owner.load(Ordering::Relaxed); if owner == id { return Ok(unsafe { (*self.local.get()).as_ref().unchecked_unwrap() }); } self.get_or_try_slow(id, owner, create) } #[cold] #[inline(never)] fn get_or_try_slow(&self, id: usize, owner: usize, create: F) -> Result<&T, E> where F: FnOnce() -> Result, E>, { if owner == 0 && self.owner.compare_and_swap(0, id, Ordering::Relaxed) == 0 { unsafe { (*self.local.get()) = Some(try!(create())); return Ok((*self.local.get()).as_ref().unchecked_unwrap()); } } match self.global.get_fast(id) { Some(x) => Ok(x), None => Ok(self.global.insert(id, try!(create()), true)), } } /// 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. pub fn iter_mut(&mut self) -> CachedIterMut { unsafe { (*self.local.get()).as_mut().into_iter().chain( self.global .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. pub fn clear(&mut self) { *self = CachedThreadLocal::new(); } } impl IntoIterator for CachedThreadLocal { type Item = Box; type IntoIter = CachedIntoIter; fn into_iter(self) -> CachedIntoIter { unsafe { (*self.local.get()).take().into_iter().chain( self.global .into_iter(), ) } } } impl<'a, T: ?Sized + Send + 'a> IntoIterator for &'a mut CachedThreadLocal { type Item = &'a mut Box; 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_default(&self) -> &T { self.get_or(|| Box::new(T::default())) } } impl fmt::Debug for CachedThreadLocal { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "ThreadLocal {{ local_data: {:?} }}", self.get()) } } /// Mutable iterator over the contents of a `CachedThreadLocal`. pub type CachedIterMut<'a, T> = Chain>, IterMut<'a, T>>; /// An iterator that moves out of a `CachedThreadLocal`. pub type CachedIntoIter = Chain>, IntoIter>; impl UnwindSafe for CachedThreadLocal {} #[cfg(test)] mod tests { use std::cell::RefCell; use std::sync::Arc; use std::sync::atomic::AtomicUsize; use std::sync::atomic::Ordering::Relaxed; use std::thread; use super::{ThreadLocal, CachedThreadLocal}; fn make_create() -> Arc Box + Send + Sync> { let count = AtomicUsize::new(0); Arc::new(move || Box::new(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 same_thread_cached() { let create = make_create(); let mut tls = CachedThreadLocal::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 different_thread_cached() { let create = make_create(); let tls = Arc::new(CachedThreadLocal::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(); }).join() .unwrap(); let mut tls = Arc::try_unwrap(tls).unwrap(); let mut v = tls.iter_mut().map(|x| **x).collect::>(); v.sort(); assert_eq!(vec![1, 2, 3], v); let mut v = tls.into_iter().map(|x| *x).collect::>(); v.sort(); assert_eq!(vec![1, 2, 3], v); } #[test] fn iter_cached() { let tls = Arc::new(CachedThreadLocal::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(); }).join() .unwrap(); let mut tls = Arc::try_unwrap(tls).unwrap(); let mut v = tls.iter_mut().map(|x| **x).collect::>(); v.sort(); assert_eq!(vec![1, 2, 3], v); let mut v = tls.into_iter().map(|x| *x).collect::>(); v.sort(); assert_eq!(vec![1, 2, 3], v); } #[test] fn is_sync() { fn foo() {} foo::>(); foo::>>(); foo::>(); foo::>>(); } } thread_local-0.3.6/src/thread_id.rs010064400017500001750000000035151312432204300154400ustar0000000000000000// 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::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 { limit: usize, free_list: BinaryHeap, } impl ThreadIdManager { fn new() -> ThreadIdManager { ThreadIdManager { limit: usize::MAX, free_list: BinaryHeap::new(), } } fn alloc(&mut self) -> usize { if let Some(id) = self.free_list.pop() { id } else { let id = self.limit; self.limit = self.limit.checked_sub(1).expect("Ran out of thread IDs"); id } } fn free(&mut self, id: usize) { self.free_list.push(id); } } lazy_static! { static ref THREAD_ID_MANAGER: Mutex = Mutex::new(ThreadIdManager::new()); } // Non-zero integer which is unique to the current thread while it is running. // A thread ID may be reused after a thread exits. struct ThreadId(usize); impl ThreadId { fn new() -> ThreadId { ThreadId(THREAD_ID_MANAGER.lock().unwrap().alloc()) } } impl Drop for ThreadId { fn drop(&mut self) { THREAD_ID_MANAGER.lock().unwrap().free(self.0); } } thread_local!(static THREAD_ID: ThreadId = ThreadId::new()); /// Returns a non-zero ID for the current thread pub fn get() -> usize { THREAD_ID.with(|x| x.0) } thread_local-0.3.6/src/unreachable.rs010064400017500001750000000044261333506773400160110ustar0000000000000000// 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. //! # unreachable //! inlined from https://github.com/reem/rust-unreachable/ //! //! An unreachable code optimization hint in stable rust, and some useful //! extension traits for `Option` and `Result`. //! /// Hint to the optimizer that any code path which calls this function is /// statically unreachable and can be removed. /// /// Calling this function in reachable code invokes undefined behavior. Be /// very, very sure this is what you want; often, a simple `panic!` is more /// suitable. #[inline] pub unsafe fn unreachable() -> ! { /// The empty type for cases which can't occur. enum Void { } let x: &Void = ::std::mem::transmute(1usize); match *x {} } /// 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() } } unsafe fn unchecked_unwrap_none(self) { if self.is_some() { unreachable() } } } impl UncheckedResultExt for Result { unsafe fn unchecked_unwrap_ok(self) -> T { match self { Ok(x) => x, Err(_) => unreachable() } } unsafe fn unchecked_unwrap_err(self) -> E { match self { Ok(_) => unreachable(), Err(e) => e } } }