1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
13 //! ## The threading model
15 //! An executing Rust program consists of a collection of native OS threads,
16 //! each with their own stack and local state. Threads can be named, and
17 //! provide some built-in support for low-level synchronization.
19 //! Communication between threads can be done through
20 //! [channels](../../std/sync/mpsc/index.html), Rust's message-passing
21 //! types, along with [other forms of thread
22 //! synchronization](../../std/sync/index.html) and shared-memory data
23 //! structures. In particular, types that are guaranteed to be
24 //! threadsafe are easily shared between threads using the
25 //! atomically-reference-counted container,
26 //! [`Arc`](../../std/sync/struct.Arc.html).
28 //! Fatal logic errors in Rust cause *thread panic*, during which
29 //! a thread will unwind the stack, running destructors and freeing
30 //! owned resources. Thread panic is unrecoverable from within
31 //! the panicking thread (i.e. there is no 'try/catch' in Rust), but
32 //! the panic may optionally be detected from a different thread. If
33 //! the main thread panics, the application will exit with a non-zero
36 //! When the main thread of a Rust program terminates, the entire program shuts
37 //! down, even if other threads are still running. However, this module provides
38 //! convenient facilities for automatically waiting for the termination of a
39 //! child thread (i.e., join).
41 //! ## Spawning a thread
43 //! A new thread can be spawned using the `thread::spawn` function:
48 //! thread::spawn(move || {
53 //! In this example, the spawned thread is "detached" from the current
54 //! thread. This means that it can outlive its parent (the thread that spawned
55 //! it), unless this parent is the main thread.
57 //! The parent thread can also wait on the completion of the child
58 //! thread; a call to `spawn` produces a `JoinHandle`, which provides
59 //! a `join` method for waiting:
64 //! let child = thread::spawn(move || {
68 //! let res = child.join();
71 //! The `join` method returns a `Result` containing `Ok` of the final
72 //! value produced by the child thread, or `Err` of the value given to
73 //! a call to `panic!` if the child panicked.
75 //! ## Configuring threads
77 //! A new thread can be configured before it is spawned via the `Builder` type,
78 //! which currently allows you to set the name and stack size for the child thread:
81 //! # #![allow(unused_must_use)]
84 //! thread::Builder::new().name("child1".to_string()).spawn(move || {
85 //! println!("Hello, world!");
89 //! ## The `Thread` type
91 //! Threads are represented via the `Thread` type, which you can get in one of
94 //! * By spawning a new thread, e.g. using the `thread::spawn` function, and
95 //! calling `thread()` on the `JoinHandle`.
96 //! * By requesting the current thread, using the `thread::current` function.
98 //! The `thread::current()` function is available even for threads not spawned
99 //! by the APIs of this module.
101 //! ## Blocking support: park and unpark
103 //! Every thread is equipped with some basic low-level blocking support, via the
104 //! `thread::park()` function and `thread::Thread::unpark()` method. `park()`
105 //! blocks the current thread, which can then be resumed from another thread by
106 //! calling the `unpark()` method on the blocked thread's handle.
108 //! Conceptually, each `Thread` handle has an associated token, which is
109 //! initially not present:
111 //! * The `thread::park()` function blocks the current thread unless or until
112 //! the token is available for its thread handle, at which point it atomically
113 //! consumes the token. It may also return *spuriously*, without consuming the
114 //! token. `thread::park_timeout()` does the same, but allows specifying a
115 //! maximum time to block the thread for.
117 //! * The `unpark()` method on a `Thread` atomically makes the token available
118 //! if it wasn't already.
120 //! In other words, each `Thread` acts a bit like a semaphore with initial count
121 //! 0, except that the semaphore is *saturating* (the count cannot go above 1),
122 //! and can return spuriously.
124 //! The API is typically used by acquiring a handle to the current thread,
125 //! placing that handle in a shared data structure so that other threads can
126 //! find it, and then `park`ing. When some desired condition is met, another
127 //! thread calls `unpark` on the handle.
129 //! The motivation for this design is twofold:
131 //! * It avoids the need to allocate mutexes and condvars when building new
132 //! synchronization primitives; the threads already provide basic blocking/signaling.
134 //! * It can be implemented very efficiently on many platforms.
136 //! ## Thread-local storage
138 //! This module also provides an implementation of thread local storage for Rust
139 //! programs. Thread local storage is a method of storing data into a global
140 //! variable which each thread in the program will have its own copy of.
141 //! Threads do not share this data, so accesses do not need to be synchronized.
143 //! At a high level, this module provides two variants of storage:
145 //! * Owned thread-local storage. This is a type of thread local key which
146 //! owns the value that it contains, and will destroy the value when the
147 //! thread exits. This variant is created with the `thread_local!` macro and
148 //! can contain any value which is `'static` (no borrowed pointers).
150 //! * Scoped thread-local storage. This type of key is used to store a reference
151 //! to a value into local storage temporarily for the scope of a function
152 //! call. There are no restrictions on what types of values can be placed
155 //! Both forms of thread local storage provide an accessor function, `with`,
156 //! which will yield a shared reference to the value to the specified
157 //! closure. Thread-local keys only allow shared access to values as there is no
158 //! way to guarantee uniqueness if a mutable borrow was allowed. Most values
159 //! will want to make use of some form of **interior mutability** through the
160 //! `Cell` or `RefCell` types.
162 #![stable(feature = "rust1", since = "1.0.0")]
167 use cell::UnsafeCell;
168 use ffi::{CStr, CString};
174 use sync::{Mutex, Condvar, Arc};
175 use sys::thread as imp;
176 use sys_common::thread_info;
177 use sys_common::util;
178 use sys_common::{AsInner, IntoInner};
181 ////////////////////////////////////////////////////////////////////////////////
182 // Thread-local storage
183 ////////////////////////////////////////////////////////////////////////////////
185 #[macro_use] mod local;
187 #[stable(feature = "rust1", since = "1.0.0")]
188 pub use self::local::{LocalKey, LocalKeyState};
190 #[unstable(feature = "libstd_thread_internals", issue = "0")]
191 #[cfg(target_thread_local)]
192 #[doc(hidden)] pub use self::local::elf::Key as __ElfLocalKeyInner;
193 #[unstable(feature = "libstd_thread_internals", issue = "0")]
194 #[doc(hidden)] pub use self::local::os::Key as __OsLocalKeyInner;
196 ////////////////////////////////////////////////////////////////////////////////
198 ////////////////////////////////////////////////////////////////////////////////
200 /// Thread configuration. Provides detailed control over the properties
201 /// and behavior of new threads.
202 #[stable(feature = "rust1", since = "1.0.0")]
204 // A name for the thread-to-be, for identification in panic messages
205 name: Option<String>,
206 // The size of the stack for the spawned thread
207 stack_size: Option<usize>,
211 /// Generates the base configuration for spawning a thread, from which
212 /// configuration methods can be chained.
213 #[stable(feature = "rust1", since = "1.0.0")]
214 pub fn new() -> Builder {
221 /// Names the thread-to-be. Currently the name is used for identification
222 /// only in panic messages.
229 /// let builder = thread::Builder::new()
230 /// .name("foo".into());
232 /// let handler = builder.spawn(|| {
233 /// assert_eq!(thread::current().name(), Some("foo"))
236 /// handler.join().unwrap();
238 #[stable(feature = "rust1", since = "1.0.0")]
239 pub fn name(mut self, name: String) -> Builder {
240 self.name = Some(name);
244 /// Sets the size of the stack for the new thread.
245 #[stable(feature = "rust1", since = "1.0.0")]
246 pub fn stack_size(mut self, size: usize) -> Builder {
247 self.stack_size = Some(size);
251 /// Spawns a new thread, and returns a join handle for it.
253 /// The child thread may outlive the parent (unless the parent thread
254 /// is the main thread; the whole process is terminated when the main
255 /// thread finishes). The join handle can be used to block on
256 /// termination of the child thread, including recovering its panics.
260 /// Unlike the `spawn` free function, this method yields an
261 /// `io::Result` to capture any failure to create the thread at
263 #[stable(feature = "rust1", since = "1.0.0")]
264 pub fn spawn<F, T>(self, f: F) -> io::Result<JoinHandle<T>> where
265 F: FnOnce() -> T, F: Send + 'static, T: Send + 'static
267 let Builder { name, stack_size } = self;
269 let stack_size = stack_size.unwrap_or(util::min_stack());
271 let my_thread = Thread::new(name);
272 let their_thread = my_thread.clone();
274 let my_packet : Arc<UnsafeCell<Option<Result<T>>>>
275 = Arc::new(UnsafeCell::new(None));
276 let their_packet = my_packet.clone();
279 if let Some(name) = their_thread.cname() {
280 imp::Thread::set_name(name);
283 thread_info::set(imp::guard::current(), their_thread);
284 let try_result = panic::catch_unwind(panic::AssertUnwindSafe(f));
285 *their_packet.get() = Some(try_result);
289 Ok(JoinHandle(JoinInner {
291 Some(imp::Thread::new(stack_size, Box::new(main))?)
294 packet: Packet(my_packet),
299 ////////////////////////////////////////////////////////////////////////////////
301 ////////////////////////////////////////////////////////////////////////////////
303 /// Spawns a new thread, returning a `JoinHandle` for it.
305 /// The join handle will implicitly *detach* the child thread upon being
306 /// dropped. In this case, the child thread may outlive the parent (unless
307 /// the parent thread is the main thread; the whole process is terminated when
308 /// the main thread finishes.) Additionally, the join handle provides a `join`
309 /// method that can be used to join the child thread. If the child thread
310 /// panics, `join` will return an `Err` containing the argument given to
315 /// Panics if the OS fails to create a thread; use `Builder::spawn`
316 /// to recover from such errors.
317 #[stable(feature = "rust1", since = "1.0.0")]
318 pub fn spawn<F, T>(f: F) -> JoinHandle<T> where
319 F: FnOnce() -> T, F: Send + 'static, T: Send + 'static
321 Builder::new().spawn(f).unwrap()
324 /// Gets a handle to the thread that invokes it.
325 #[stable(feature = "rust1", since = "1.0.0")]
326 pub fn current() -> Thread {
327 thread_info::current_thread().expect("use of std::thread::current() is not \
328 possible after the thread's local \
329 data has been destroyed")
332 /// Cooperatively gives up a timeslice to the OS scheduler.
333 #[stable(feature = "rust1", since = "1.0.0")]
335 imp::Thread::yield_now()
338 /// Determines whether the current thread is unwinding because of panic.
342 /// ```rust,should_panic
345 /// struct SomeStruct;
347 /// impl Drop for SomeStruct {
348 /// fn drop(&mut self) {
349 /// if thread::panicking() {
350 /// println!("dropped while unwinding");
352 /// println!("dropped while not unwinding");
359 /// let a = SomeStruct;
364 /// let b = SomeStruct;
369 #[stable(feature = "rust1", since = "1.0.0")]
370 pub fn panicking() -> bool {
371 panicking::panicking()
374 /// Puts the current thread to sleep for the specified amount of time.
376 /// The thread may sleep longer than the duration specified due to scheduling
377 /// specifics or platform-dependent functionality. Note that on unix platforms
378 /// this function will not return early due to a signal being received or a
380 #[stable(feature = "rust1", since = "1.0.0")]
381 #[rustc_deprecated(since = "1.6.0", reason = "replaced by `std::thread::sleep`")]
382 pub fn sleep_ms(ms: u32) {
383 sleep(Duration::from_millis(ms as u64))
386 /// Puts the current thread to sleep for the specified amount of time.
388 /// The thread may sleep longer than the duration specified due to scheduling
389 /// specifics or platform-dependent functionality.
391 /// # Platform behavior
393 /// On Unix platforms this function will not return early due to a
394 /// signal being received or a spurious wakeup. Platforms which do not support
395 /// nanosecond precision for sleeping will have `dur` rounded up to the nearest
396 /// granularity of time they can sleep for.
401 /// use std::{thread, time};
403 /// let ten_millis = time::Duration::from_millis(10);
404 /// let now = time::Instant::now();
406 /// thread::sleep(ten_millis);
408 /// assert!(now.elapsed() >= ten_millis);
410 #[stable(feature = "thread_sleep", since = "1.4.0")]
411 pub fn sleep(dur: Duration) {
412 imp::Thread::sleep(dur)
415 /// Blocks unless or until the current thread's token is made available.
417 /// Every thread is equipped with some basic low-level blocking support, via
418 /// the `park()` function and the [`unpark()`][unpark] method. These can be
419 /// used as a more CPU-efficient implementation of a spinlock.
421 /// [unpark]: struct.Thread.html#method.unpark
423 /// The API is typically used by acquiring a handle to the current thread,
424 /// placing that handle in a shared data structure so that other threads can
425 /// find it, and then parking (in a loop with a check for the token actually
428 /// A call to `park` does not guarantee that the thread will remain parked
429 /// forever, and callers should be prepared for this possibility.
431 /// See the [module documentation][thread] for more detail.
433 /// [thread]: index.html
435 // The implementation currently uses the trivial strategy of a Mutex+Condvar
436 // with wakeup flag, which does not actually allow spurious wakeups. In the
437 // future, this will be implemented in a more efficient way, perhaps along the lines of
438 // http://cr.openjdk.java.net/~stefank/6989984.1/raw_files/new/src/os/linux/vm/os_linux.cpp
439 // or futuxes, and in either case may allow spurious wakeups.
440 #[stable(feature = "rust1", since = "1.0.0")]
442 let thread = current();
443 let mut guard = thread.inner.lock.lock().unwrap();
445 guard = thread.inner.cvar.wait(guard).unwrap();
450 /// Use [park_timeout].
452 /// Blocks unless or until the current thread's token is made available or
453 /// the specified duration has been reached (may wake spuriously).
455 /// The semantics of this function are equivalent to `park()` except that the
456 /// thread will be blocked for roughly no longer than `ms`. This method
457 /// should not be used for precise timing due to anomalies such as
458 /// preemption or platform differences that may not cause the maximum
459 /// amount of time waited to be precisely `ms` long.
461 /// See the [module documentation][thread] for more detail.
463 /// [thread]: index.html
464 /// [park_timeout]: fn.park_timeout.html
465 #[stable(feature = "rust1", since = "1.0.0")]
466 #[rustc_deprecated(since = "1.6.0", reason = "replaced by `std::thread::park_timeout`")]
467 pub fn park_timeout_ms(ms: u32) {
468 park_timeout(Duration::from_millis(ms as u64))
471 /// Blocks unless or until the current thread's token is made available or
472 /// the specified duration has been reached (may wake spuriously).
474 /// The semantics of this function are equivalent to `park()` except that the
475 /// thread will be blocked for roughly no longer than `dur`. This method
476 /// should not be used for precise timing due to anomalies such as
477 /// preemption or platform differences that may not cause the maximum
478 /// amount of time waited to be precisely `dur` long.
480 /// See the module doc for more detail.
482 /// # Platform behavior
484 /// Platforms which do not support nanosecond precision for sleeping will have
485 /// `dur` rounded up to the nearest granularity of time they can sleep for.
489 /// Waiting for the complete expiration of the timeout:
492 /// use std::thread::park_timeout;
493 /// use std::time::{Instant, Duration};
495 /// let timeout = Duration::from_secs(2);
496 /// let beginning_park = Instant::now();
497 /// park_timeout(timeout);
499 /// while beginning_park.elapsed() < timeout {
500 /// println!("restarting park_timeout after {:?}", beginning_park.elapsed());
501 /// let timeout = timeout - beginning_park.elapsed();
502 /// park_timeout(timeout);
505 #[stable(feature = "park_timeout", since = "1.4.0")]
506 pub fn park_timeout(dur: Duration) {
507 let thread = current();
508 let mut guard = thread.inner.lock.lock().unwrap();
510 let (g, _) = thread.inner.cvar.wait_timeout(guard, dur).unwrap();
516 ////////////////////////////////////////////////////////////////////////////////
518 ////////////////////////////////////////////////////////////////////////////////
520 /// The internal representation of a `Thread` handle
522 name: Option<CString>, // Guaranteed to be UTF-8
523 lock: Mutex<bool>, // true when there is a buffered unpark
528 #[stable(feature = "rust1", since = "1.0.0")]
529 /// A handle to a thread.
535 // Used only internally to construct a thread object without spawning
536 fn new(name: Option<String>) -> Thread {
537 let cname = name.map(|n| {
538 CString::new(n).expect("thread name may not contain interior null bytes")
541 inner: Arc::new(Inner {
543 lock: Mutex::new(false),
544 cvar: Condvar::new(),
549 /// Atomically makes the handle's token available if it is not already.
551 /// See the module doc for more detail.
552 #[stable(feature = "rust1", since = "1.0.0")]
553 pub fn unpark(&self) {
554 let mut guard = self.inner.lock.lock().unwrap();
557 self.inner.cvar.notify_one();
561 /// Gets the thread's name.
565 /// Threads by default have no name specified:
570 /// let builder = thread::Builder::new();
572 /// let handler = builder.spawn(|| {
573 /// assert!(thread::current().name().is_none());
576 /// handler.join().unwrap();
579 /// Thread with a specified name:
584 /// let builder = thread::Builder::new()
585 /// .name("foo".into());
587 /// let handler = builder.spawn(|| {
588 /// assert_eq!(thread::current().name(), Some("foo"))
591 /// handler.join().unwrap();
593 #[stable(feature = "rust1", since = "1.0.0")]
594 pub fn name(&self) -> Option<&str> {
595 self.cname().map(|s| unsafe { str::from_utf8_unchecked(s.to_bytes()) } )
598 fn cname(&self) -> Option<&CStr> {
599 self.inner.name.as_ref().map(|s| &**s)
603 #[stable(feature = "rust1", since = "1.0.0")]
604 impl fmt::Debug for Thread {
605 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
606 fmt::Debug::fmt(&self.name(), f)
610 // a hack to get around privacy restrictions
611 impl thread_info::NewThread for Thread {
612 fn new(name: Option<String>) -> Thread { Thread::new(name) }
615 ////////////////////////////////////////////////////////////////////////////////
617 ////////////////////////////////////////////////////////////////////////////////
619 /// Indicates the manner in which a thread exited.
621 /// A thread that completes without panicking is considered to exit successfully.
622 #[stable(feature = "rust1", since = "1.0.0")]
623 pub type Result<T> = ::result::Result<T, Box<Any + Send + 'static>>;
625 // This packet is used to communicate the return value between the child thread
626 // and the parent thread. Memory is shared through the `Arc` within and there's
627 // no need for a mutex here because synchronization happens with `join()` (the
628 // parent thread never reads this packet until the child has exited).
630 // This packet itself is then stored into a `JoinInner` which in turns is placed
631 // in `JoinHandle` and `JoinGuard`. Due to the usage of `UnsafeCell` we need to
632 // manually worry about impls like Send and Sync. The type `T` should
633 // already always be Send (otherwise the thread could not have been created) and
634 // this type is inherently Sync because no methods take &self. Regardless,
635 // however, we add inheriting impls for Send/Sync to this type to ensure it's
636 // Send/Sync and that future modifications will still appropriately classify it.
637 struct Packet<T>(Arc<UnsafeCell<Option<Result<T>>>>);
639 unsafe impl<T: Send> Send for Packet<T> {}
640 unsafe impl<T: Sync> Sync for Packet<T> {}
642 /// Inner representation for JoinHandle
643 struct JoinInner<T> {
644 native: Option<imp::Thread>,
649 impl<T> JoinInner<T> {
650 fn join(&mut self) -> Result<T> {
651 self.native.take().unwrap().join();
653 (*self.packet.0.get()).take().unwrap()
658 /// An owned permission to join on a thread (block on its termination).
660 /// A `JoinHandle` *detaches* the child thread when it is dropped.
662 /// Due to platform restrictions, it is not possible to `Clone` this
663 /// handle: the ability to join a child thread is a uniquely-owned
666 /// This `struct` is created by the [`thread::spawn`] function and the
667 /// [`thread::Builder::spawn`] method.
671 /// Creation from [`thread::spawn`]:
676 /// let join_handle: thread::JoinHandle<_> = thread::spawn(|| {
677 /// // some work here
681 /// Creation from [`thread::Builder::spawn`]:
686 /// let builder = thread::Builder::new();
688 /// let join_handle: thread::JoinHandle<_> = builder.spawn(|| {
689 /// // some work here
693 /// [`thread::spawn`]: fn.spawn.html
694 /// [`thread::Builder::spawn`]: struct.Builder.html#method.spawn
695 #[stable(feature = "rust1", since = "1.0.0")]
696 pub struct JoinHandle<T>(JoinInner<T>);
698 impl<T> JoinHandle<T> {
699 /// Extracts a handle to the underlying thread
700 #[stable(feature = "rust1", since = "1.0.0")]
701 pub fn thread(&self) -> &Thread {
705 /// Waits for the associated thread to finish.
707 /// If the child thread panics, `Err` is returned with the parameter given
709 #[stable(feature = "rust1", since = "1.0.0")]
710 pub fn join(mut self) -> Result<T> {
715 impl<T> AsInner<imp::Thread> for JoinHandle<T> {
716 fn as_inner(&self) -> &imp::Thread { self.0.native.as_ref().unwrap() }
719 impl<T> IntoInner<imp::Thread> for JoinHandle<T> {
720 fn into_inner(self) -> imp::Thread { self.0.native.unwrap() }
723 fn _assert_sync_and_send() {
724 fn _assert_both<T: Send + Sync>() {}
725 _assert_both::<JoinHandle<()>>();
726 _assert_both::<Thread>();
729 ////////////////////////////////////////////////////////////////////////////////
731 ////////////////////////////////////////////////////////////////////////////////
738 use sync::mpsc::{channel, Sender};
740 use super::{Builder};
745 // !!! These tests are dangerous. If something is buggy, they will hang, !!!
746 // !!! instead of exiting cleanly. This might wedge the buildbots. !!!
749 fn test_unnamed_thread() {
750 thread::spawn(move|| {
751 assert!(thread::current().name().is_none());
752 }).join().ok().unwrap();
756 fn test_named_thread() {
757 Builder::new().name("ada lovelace".to_string()).spawn(move|| {
758 assert!(thread::current().name().unwrap() == "ada lovelace".to_string());
759 }).unwrap().join().unwrap();
764 fn test_invalid_named_thread() {
765 let _ = Builder::new().name("ada l\0velace".to_string()).spawn(|| {});
769 fn test_run_basic() {
770 let (tx, rx) = channel();
771 thread::spawn(move|| {
772 tx.send(()).unwrap();
778 fn test_join_panic() {
779 match thread::spawn(move|| {
782 result::Result::Err(_) => (),
783 result::Result::Ok(()) => panic!()
788 fn test_spawn_sched() {
791 let (tx, rx) = channel();
793 fn f(i: i32, tx: Sender<()>) {
795 thread::spawn(move|| {
797 tx.send(()).unwrap();
809 fn test_spawn_sched_childs_on_default_sched() {
810 let (tx, rx) = channel();
812 thread::spawn(move|| {
813 thread::spawn(move|| {
814 tx.send(()).unwrap();
821 fn avoid_copying_the_body<F>(spawnfn: F) where F: FnOnce(Box<Fn() + Send>) {
822 let (tx, rx) = channel();
824 let x: Box<_> = box 1;
825 let x_in_parent = (&*x) as *const i32 as usize;
827 spawnfn(Box::new(move|| {
828 let x_in_child = (&*x) as *const i32 as usize;
829 tx.send(x_in_child).unwrap();
832 let x_in_child = rx.recv().unwrap();
833 assert_eq!(x_in_parent, x_in_child);
837 fn test_avoid_copying_the_body_spawn() {
838 avoid_copying_the_body(|v| {
839 thread::spawn(move || v());
844 fn test_avoid_copying_the_body_thread_spawn() {
845 avoid_copying_the_body(|f| {
846 thread::spawn(move|| {
853 fn test_avoid_copying_the_body_join() {
854 avoid_copying_the_body(|f| {
855 let _ = thread::spawn(move|| {
862 fn test_child_doesnt_ref_parent() {
863 // If the child refcounts the parent thread, this will stack overflow when
864 // climbing the thread tree to dereference each ancestor. (See #1789)
865 // (well, it would if the constant were 8000+ - I lowered it to be more
866 // valgrind-friendly. try this at home, instead..!)
867 const GENERATIONS: u32 = 16;
868 fn child_no(x: u32) -> Box<Fn() + Send> {
869 return Box::new(move|| {
871 thread::spawn(move|| child_no(x+1)());
875 thread::spawn(|| child_no(0)());
879 fn test_simple_newsched_spawn() {
880 thread::spawn(move || {});
884 fn test_try_panic_message_static_str() {
885 match thread::spawn(move|| {
886 panic!("static string");
889 type T = &'static str;
890 assert!(e.is::<T>());
891 assert_eq!(*e.downcast::<T>().unwrap(), "static string");
898 fn test_try_panic_message_owned_str() {
899 match thread::spawn(move|| {
900 panic!("owned string".to_string());
904 assert!(e.is::<T>());
905 assert_eq!(*e.downcast::<T>().unwrap(), "owned string".to_string());
912 fn test_try_panic_message_any() {
913 match thread::spawn(move|| {
914 panic!(box 413u16 as Box<Any + Send>);
917 type T = Box<Any + Send>;
918 assert!(e.is::<T>());
919 let any = e.downcast::<T>().unwrap();
920 assert!(any.is::<u16>());
921 assert_eq!(*any.downcast::<u16>().unwrap(), 413);
928 fn test_try_panic_message_unit_struct() {
931 match thread::spawn(move|| {
934 Err(ref e) if e.is::<Juju>() => {}
935 Err(_) | Ok(()) => panic!()
940 fn test_park_timeout_unpark_before() {
942 thread::current().unpark();
943 thread::park_timeout(Duration::from_millis(u32::MAX as u64));
948 fn test_park_timeout_unpark_not_called() {
950 thread::park_timeout(Duration::from_millis(10));
955 fn test_park_timeout_unpark_called_other_thread() {
957 let th = thread::current();
959 let _guard = thread::spawn(move || {
960 super::sleep(Duration::from_millis(50));
964 thread::park_timeout(Duration::from_millis(u32::MAX as u64));
969 fn sleep_ms_smoke() {
970 thread::sleep(Duration::from_millis(2));
973 // NOTE: the corresponding test for stderr is in run-pass/thread-stderr, due
974 // to the test harness apparently interfering with stderr configuration.