-// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-use sync::atomic::{AtomicUsize, Ordering};
-use sync::{mutex, MutexGuard, PoisonError};
-use sys_common::condvar as sys;
-use sys_common::mutex as sys_mutex;
-use sys_common::poison::{self, LockResult};
-use time::Duration;
+use crate::fmt;
+use crate::sync::atomic::{AtomicUsize, Ordering};
+use crate::sync::{mutex, MutexGuard, PoisonError};
+use crate::sys_common::condvar as sys;
+use crate::sys_common::mutex as sys_mutex;
+use crate::sys_common::poison::{self, LockResult};
+use crate::time::{Duration, Instant};
/// A type indicating whether a timed wait on a condition variable returned
/// due to a time out or not.
+///
+/// It is returned by the [`wait_timeout`] method.
+///
+/// [`wait_timeout`]: struct.Condvar.html#method.wait_timeout
#[derive(Debug, PartialEq, Eq, Copy, Clone)]
#[stable(feature = "wait_timeout", since = "1.5.0")]
pub struct WaitTimeoutResult(bool);
impl WaitTimeoutResult {
- /// Returns whether the wait was known to have timed out.
+ /// Returns `true` if the wait was known to have timed out.
+ ///
+ /// # Examples
+ ///
+ /// This example spawns a thread which will update the boolean value and
+ /// then wait 100 milliseconds before notifying the condvar.
+ ///
+ /// The main thread will wait with a timeout on the condvar and then leave
+ /// once the boolean has been updated and notified.
+ ///
+ /// ```
+ /// use std::sync::{Arc, Condvar, Mutex};
+ /// use std::thread;
+ /// use std::time::Duration;
+ ///
+ /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
+ /// let pair2 = pair.clone();
+ ///
+ /// thread::spawn(move || {
+ /// let (lock, cvar) = &*pair2;
+ ///
+ /// // Let's wait 20 milliseconds before notifying the condvar.
+ /// thread::sleep(Duration::from_millis(20));
+ ///
+ /// let mut started = lock.lock().unwrap();
+ /// // We update the boolean value.
+ /// *started = true;
+ /// cvar.notify_one();
+ /// });
+ ///
+ /// // Wait for the thread to start up.
+ /// let (lock, cvar) = &*pair;
+ /// let mut started = lock.lock().unwrap();
+ /// loop {
+ /// // Let's put a timeout on the condvar's wait.
+ /// let result = cvar.wait_timeout(started, Duration::from_millis(10)).unwrap();
+ /// // 10 milliseconds have passed, or maybe the value changed!
+ /// started = result.0;
+ /// if *started == true {
+ /// // We received the notification and the value has been updated, we can leave.
+ /// break
+ /// }
+ /// }
+ /// ```
#[stable(feature = "wait_timeout", since = "1.5.0")]
pub fn timed_out(&self) -> bool {
self.0
/// consumes no CPU time while waiting for an event to occur. Condition
/// variables are typically associated with a boolean predicate (a condition)
/// and a mutex. The predicate is always verified inside of the mutex before
-/// determining that thread must block.
+/// determining that a thread must block.
///
/// Functions in this module will block the current **thread** of execution and
/// are bindings to system-provided condition variables where possible. Note
/// let pair = Arc::new((Mutex::new(false), Condvar::new()));
/// let pair2 = pair.clone();
///
-/// // Inside of our lock, spawn a new thread, and then wait for it to start
+/// // Inside of our lock, spawn a new thread, and then wait for it to start.
/// thread::spawn(move|| {
-/// let &(ref lock, ref cvar) = &*pair2;
+/// let (lock, cvar) = &*pair2;
/// let mut started = lock.lock().unwrap();
/// *started = true;
+/// // We notify the condvar that the value has changed.
/// cvar.notify_one();
/// });
///
-/// // wait for the thread to start up
-/// let &(ref lock, ref cvar) = &*pair;
+/// // Wait for the thread to start up.
+/// let (lock, cvar) = &*pair;
/// let mut started = lock.lock().unwrap();
/// while !*started {
/// started = cvar.wait(started).unwrap();
impl Condvar {
/// Creates a new condition variable which is ready to be waited on and
/// notified.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use std::sync::Condvar;
+ ///
+ /// let condvar = Condvar::new();
+ /// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn new() -> Condvar {
- let mut c = Condvar {
- inner: box sys::Condvar::new(),
- mutex: AtomicUsize::new(0),
- };
+ let mut c = Condvar { inner: box sys::Condvar::new(), mutex: AtomicUsize::new(0) };
unsafe {
c.inner.init();
}
/// notification.
///
/// This function will atomically unlock the mutex specified (represented by
- /// `mutex_guard`) and block the current thread. This means that any calls
- /// to `notify_*()` which happen logically after the mutex is unlocked are
- /// candidates to wake this thread up. When this function call returns, the
- /// lock specified will have been re-acquired.
+ /// `guard`) and block the current thread. This means that any calls
+ /// to [`notify_one`] or [`notify_all`] which happen logically after the
+ /// mutex is unlocked are candidates to wake this thread up. When this
+ /// function call returns, the lock specified will have been re-acquired.
///
/// Note that this function is susceptible to spurious wakeups. Condition
/// variables normally have a boolean predicate associated with them, and
///
/// This function will return an error if the mutex being waited on is
/// poisoned when this thread re-acquires the lock. For more information,
- /// see information about poisoning on the Mutex type.
+ /// see information about [poisoning] on the [`Mutex`] type.
///
/// # Panics
///
- /// This function will `panic!()` if it is used with more than one mutex
+ /// This function will [`panic!`] if it is used with more than one mutex
/// over time. Each condition variable is dynamically bound to exactly one
/// mutex to ensure defined behavior across platforms. If this functionality
/// is not desired, then unsafe primitives in `sys` are provided.
+ ///
+ /// [`notify_one`]: #method.notify_one
+ /// [`notify_all`]: #method.notify_all
+ /// [poisoning]: ../sync/struct.Mutex.html#poisoning
+ /// [`Mutex`]: ../sync/struct.Mutex.html
+ /// [`panic!`]: ../../std/macro.panic.html
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use std::sync::{Arc, Mutex, Condvar};
+ /// use std::thread;
+ ///
+ /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
+ /// let pair2 = pair.clone();
+ ///
+ /// thread::spawn(move|| {
+ /// let (lock, cvar) = &*pair2;
+ /// let mut started = lock.lock().unwrap();
+ /// *started = true;
+ /// // We notify the condvar that the value has changed.
+ /// cvar.notify_one();
+ /// });
+ ///
+ /// // Wait for the thread to start up.
+ /// let (lock, cvar) = &*pair;
+ /// let mut started = lock.lock().unwrap();
+ /// // As long as the value inside the `Mutex<bool>` is `false`, we wait.
+ /// while !*started {
+ /// started = cvar.wait(started).unwrap();
+ /// }
+ /// ```
#[stable(feature = "rust1", since = "1.0.0")]
- pub fn wait<'a, T>(&self, guard: MutexGuard<'a, T>)
- -> LockResult<MutexGuard<'a, T>> {
+ pub fn wait<'a, T>(&self, guard: MutexGuard<'a, T>) -> LockResult<MutexGuard<'a, T>> {
let poisoned = unsafe {
let lock = mutex::guard_lock(&guard);
self.verify(lock);
self.inner.wait(lock);
mutex::guard_poison(&guard).get()
};
- if poisoned {
- Err(PoisonError::new(guard))
- } else {
- Ok(guard)
+ if poisoned { Err(PoisonError::new(guard)) } else { Ok(guard) }
+ }
+
+ /// Blocks the current thread until this condition variable receives a
+ /// notification and the provided condition is false.
+ ///
+ /// This function will atomically unlock the mutex specified (represented by
+ /// `guard`) and block the current thread. This means that any calls
+ /// to [`notify_one`] or [`notify_all`] which happen logically after the
+ /// mutex is unlocked are candidates to wake this thread up. When this
+ /// function call returns, the lock specified will have been re-acquired.
+ ///
+ /// # Errors
+ ///
+ /// This function will return an error if the mutex being waited on is
+ /// poisoned when this thread re-acquires the lock. For more information,
+ /// see information about [poisoning] on the [`Mutex`] type.
+ ///
+ /// [`notify_one`]: #method.notify_one
+ /// [`notify_all`]: #method.notify_all
+ /// [poisoning]: ../sync/struct.Mutex.html#poisoning
+ /// [`Mutex`]: ../sync/struct.Mutex.html
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use std::sync::{Arc, Mutex, Condvar};
+ /// use std::thread;
+ ///
+ /// let pair = Arc::new((Mutex::new(true), Condvar::new()));
+ /// let pair2 = pair.clone();
+ ///
+ /// thread::spawn(move|| {
+ /// let (lock, cvar) = &*pair2;
+ /// let mut pending = lock.lock().unwrap();
+ /// *pending = false;
+ /// // We notify the condvar that the value has changed.
+ /// cvar.notify_one();
+ /// });
+ ///
+ /// // Wait for the thread to start up.
+ /// let (lock, cvar) = &*pair;
+ /// // As long as the value inside the `Mutex<bool>` is `true`, we wait.
+ /// let _guard = cvar.wait_while(lock.lock().unwrap(), |pending| { *pending }).unwrap();
+ /// ```
+ #[stable(feature = "wait_until", since = "1.42.0")]
+ pub fn wait_while<'a, T, F>(
+ &self,
+ mut guard: MutexGuard<'a, T>,
+ mut condition: F,
+ ) -> LockResult<MutexGuard<'a, T>>
+ where
+ F: FnMut(&mut T) -> bool,
+ {
+ while condition(&mut *guard) {
+ guard = self.wait(guard)?;
}
+ Ok(guard)
}
/// Waits on this condition variable for a notification, timing out after a
/// specified duration.
///
- /// The semantics of this function are equivalent to `wait()`
+ /// The semantics of this function are equivalent to [`wait`]
/// except that the thread will be blocked for roughly no longer
/// than `ms` milliseconds. This method should not be used for
/// precise timing due to anomalies such as preemption or platform
/// The returned boolean is `false` only if the timeout is known
/// to have elapsed.
///
- /// Like `wait`, the lock specified will be re-acquired when this function
+ /// Like [`wait`], the lock specified will be re-acquired when this function
/// returns, regardless of whether the timeout elapsed or not.
+ ///
+ /// [`wait`]: #method.wait
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use std::sync::{Arc, Mutex, Condvar};
+ /// use std::thread;
+ ///
+ /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
+ /// let pair2 = pair.clone();
+ ///
+ /// thread::spawn(move|| {
+ /// let (lock, cvar) = &*pair2;
+ /// let mut started = lock.lock().unwrap();
+ /// *started = true;
+ /// // We notify the condvar that the value has changed.
+ /// cvar.notify_one();
+ /// });
+ ///
+ /// // Wait for the thread to start up.
+ /// let (lock, cvar) = &*pair;
+ /// let mut started = lock.lock().unwrap();
+ /// // As long as the value inside the `Mutex<bool>` is `false`, we wait.
+ /// loop {
+ /// let result = cvar.wait_timeout_ms(started, 10).unwrap();
+ /// // 10 milliseconds have passed, or maybe the value changed!
+ /// started = result.0;
+ /// if *started == true {
+ /// // We received the notification and the value has been updated, we can leave.
+ /// break
+ /// }
+ /// }
+ /// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_deprecated(since = "1.6.0", reason = "replaced by `std::sync::Condvar::wait_timeout`")]
- pub fn wait_timeout_ms<'a, T>(&self, guard: MutexGuard<'a, T>, ms: u32)
- -> LockResult<(MutexGuard<'a, T>, bool)> {
+ pub fn wait_timeout_ms<'a, T>(
+ &self,
+ guard: MutexGuard<'a, T>,
+ ms: u32,
+ ) -> LockResult<(MutexGuard<'a, T>, bool)> {
let res = self.wait_timeout(guard, Duration::from_millis(ms as u64));
- poison::map_result(res, |(a, b)| {
- (a, !b.timed_out())
- })
+ poison::map_result(res, |(a, b)| (a, !b.timed_out()))
}
/// Waits on this condition variable for a notification, timing out after a
/// specified duration.
///
- /// The semantics of this function are equivalent to `wait()` except that
+ /// The semantics of this function are equivalent to [`wait`] except that
/// the thread will be blocked for roughly no longer than `dur`. This
/// method should not be used for precise timing due to anomalies such as
/// preemption or platform differences that may not cause the maximum
///
/// Note that the best effort is made to ensure that the time waited is
/// measured with a monotonic clock, and not affected by the changes made to
- /// the system time.
+ /// the system time. This function is susceptible to spurious wakeups.
+ /// Condition variables normally have a boolean predicate associated with
+ /// them, and the predicate must always be checked each time this function
+ /// returns to protect against spurious wakeups. Additionally, it is
+ /// typically desirable for the timeout to not exceed some duration in
+ /// spite of spurious wakes, thus the sleep-duration is decremented by the
+ /// amount slept. Alternatively, use the `wait_timeout_while` method
+ /// to wait with a timeout while a predicate is true.
///
- /// The returned `WaitTimeoutResult` value indicates if the timeout is
+ /// The returned [`WaitTimeoutResult`] value indicates if the timeout is
/// known to have elapsed.
///
- /// Like `wait`, the lock specified will be re-acquired when this function
+ /// Like [`wait`], the lock specified will be re-acquired when this function
/// returns, regardless of whether the timeout elapsed or not.
+ ///
+ /// [`wait`]: #method.wait
+ /// [`wait_timeout_while`]: #method.wait_timeout_while
+ /// [`WaitTimeoutResult`]: struct.WaitTimeoutResult.html
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use std::sync::{Arc, Mutex, Condvar};
+ /// use std::thread;
+ /// use std::time::Duration;
+ ///
+ /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
+ /// let pair2 = pair.clone();
+ ///
+ /// thread::spawn(move|| {
+ /// let (lock, cvar) = &*pair2;
+ /// let mut started = lock.lock().unwrap();
+ /// *started = true;
+ /// // We notify the condvar that the value has changed.
+ /// cvar.notify_one();
+ /// });
+ ///
+ /// // wait for the thread to start up
+ /// let (lock, cvar) = &*pair;
+ /// let mut started = lock.lock().unwrap();
+ /// // as long as the value inside the `Mutex<bool>` is `false`, we wait
+ /// loop {
+ /// let result = cvar.wait_timeout(started, Duration::from_millis(10)).unwrap();
+ /// // 10 milliseconds have passed, or maybe the value changed!
+ /// started = result.0;
+ /// if *started == true {
+ /// // We received the notification and the value has been updated, we can leave.
+ /// break
+ /// }
+ /// }
+ /// ```
#[stable(feature = "wait_timeout", since = "1.5.0")]
- pub fn wait_timeout<'a, T>(&self, guard: MutexGuard<'a, T>,
- dur: Duration)
- -> LockResult<(MutexGuard<'a, T>, WaitTimeoutResult)> {
+ pub fn wait_timeout<'a, T>(
+ &self,
+ guard: MutexGuard<'a, T>,
+ dur: Duration,
+ ) -> LockResult<(MutexGuard<'a, T>, WaitTimeoutResult)> {
let (poisoned, result) = unsafe {
let lock = mutex::guard_lock(&guard);
self.verify(lock);
let success = self.inner.wait_timeout(lock, dur);
(mutex::guard_poison(&guard).get(), WaitTimeoutResult(!success))
};
- if poisoned {
- Err(PoisonError::new((guard, result)))
- } else {
- Ok((guard, result))
+ if poisoned { Err(PoisonError::new((guard, result))) } else { Ok((guard, result)) }
+ }
+
+ /// Waits on this condition variable for a notification, timing out after a
+ /// specified duration.
+ ///
+ /// The semantics of this function are equivalent to [`wait_while`] except
+ /// that the thread will be blocked for roughly no longer than `dur`. This
+ /// method should not be used for precise timing due to anomalies such as
+ /// preemption or platform differences that may not cause the maximum
+ /// amount of time waited to be precisely `dur`.
+ ///
+ /// Note that the best effort is made to ensure that the time waited is
+ /// measured with a monotonic clock, and not affected by the changes made to
+ /// the system time.
+ ///
+ /// The returned [`WaitTimeoutResult`] value indicates if the timeout is
+ /// known to have elapsed without the condition being met.
+ ///
+ /// Like [`wait_while`], the lock specified will be re-acquired when this
+ /// function returns, regardless of whether the timeout elapsed or not.
+ ///
+ /// [`wait_while`]: #method.wait_while
+ /// [`wait_timeout`]: #method.wait_timeout
+ /// [`WaitTimeoutResult`]: struct.WaitTimeoutResult.html
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use std::sync::{Arc, Mutex, Condvar};
+ /// use std::thread;
+ /// use std::time::Duration;
+ ///
+ /// let pair = Arc::new((Mutex::new(true), Condvar::new()));
+ /// let pair2 = pair.clone();
+ ///
+ /// thread::spawn(move|| {
+ /// let (lock, cvar) = &*pair2;
+ /// let mut pending = lock.lock().unwrap();
+ /// *pending = false;
+ /// // We notify the condvar that the value has changed.
+ /// cvar.notify_one();
+ /// });
+ ///
+ /// // wait for the thread to start up
+ /// let (lock, cvar) = &*pair;
+ /// let result = cvar.wait_timeout_while(
+ /// lock.lock().unwrap(),
+ /// Duration::from_millis(100),
+ /// |&mut pending| pending,
+ /// ).unwrap();
+ /// if result.1.timed_out() {
+ /// // timed-out without the condition ever evaluating to false.
+ /// }
+ /// // access the locked mutex via result.0
+ /// ```
+ #[stable(feature = "wait_timeout_until", since = "1.42.0")]
+ pub fn wait_timeout_while<'a, T, F>(
+ &self,
+ mut guard: MutexGuard<'a, T>,
+ dur: Duration,
+ mut condition: F,
+ ) -> LockResult<(MutexGuard<'a, T>, WaitTimeoutResult)>
+ where
+ F: FnMut(&mut T) -> bool,
+ {
+ let start = Instant::now();
+ loop {
+ if !condition(&mut *guard) {
+ return Ok((guard, WaitTimeoutResult(false)));
+ }
+ let timeout = match dur.checked_sub(start.elapsed()) {
+ Some(timeout) => timeout,
+ None => return Ok((guard, WaitTimeoutResult(true))),
+ };
+ guard = self.wait_timeout(guard, timeout)?.0;
}
}
/// Wakes up one blocked thread on this condvar.
///
/// If there is a blocked thread on this condition variable, then it will
- /// be woken up from its call to `wait` or `wait_timeout`. Calls to
+ /// be woken up from its call to [`wait`] or [`wait_timeout`]. Calls to
/// `notify_one` are not buffered in any way.
///
- /// To wake up all threads, see `notify_all()`.
+ /// To wake up all threads, see [`notify_all`].
+ ///
+ /// [`wait`]: #method.wait
+ /// [`wait_timeout`]: #method.wait_timeout
+ /// [`notify_all`]: #method.notify_all
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use std::sync::{Arc, Mutex, Condvar};
+ /// use std::thread;
+ ///
+ /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
+ /// let pair2 = pair.clone();
+ ///
+ /// thread::spawn(move|| {
+ /// let (lock, cvar) = &*pair2;
+ /// let mut started = lock.lock().unwrap();
+ /// *started = true;
+ /// // We notify the condvar that the value has changed.
+ /// cvar.notify_one();
+ /// });
+ ///
+ /// // Wait for the thread to start up.
+ /// let (lock, cvar) = &*pair;
+ /// let mut started = lock.lock().unwrap();
+ /// // As long as the value inside the `Mutex<bool>` is `false`, we wait.
+ /// while !*started {
+ /// started = cvar.wait(started).unwrap();
+ /// }
+ /// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn notify_one(&self) {
unsafe { self.inner.notify_one() }
/// variable are awoken. Calls to `notify_all()` are not buffered in any
/// way.
///
- /// To wake up only one thread, see `notify_one()`.
+ /// To wake up only one thread, see [`notify_one`].
+ ///
+ /// [`notify_one`]: #method.notify_one
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use std::sync::{Arc, Mutex, Condvar};
+ /// use std::thread;
+ ///
+ /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
+ /// let pair2 = pair.clone();
+ ///
+ /// thread::spawn(move|| {
+ /// let (lock, cvar) = &*pair2;
+ /// let mut started = lock.lock().unwrap();
+ /// *started = true;
+ /// // We notify the condvar that the value has changed.
+ /// cvar.notify_all();
+ /// });
+ ///
+ /// // Wait for the thread to start up.
+ /// let (lock, cvar) = &*pair;
+ /// let mut started = lock.lock().unwrap();
+ /// // As long as the value inside the `Mutex<bool>` is `false`, we wait.
+ /// while !*started {
+ /// started = cvar.wait(started).unwrap();
+ /// }
+ /// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn notify_all(&self) {
unsafe { self.inner.notify_all() }
// Anything else and we're using more than one mutex on this cvar,
// which is currently disallowed.
- _ => panic!("attempted to use a condition variable with two \
- mutexes"),
+ _ => panic!(
+ "attempted to use a condition variable with two \
+ mutexes"
+ ),
}
}
}
-#[stable(feature = "condvar_default", since = "1.9.0")]
+#[stable(feature = "std_debug", since = "1.16.0")]
+impl fmt::Debug for Condvar {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.pad("Condvar { .. }")
+ }
+}
+
+#[stable(feature = "condvar_default", since = "1.10.0")]
impl Default for Condvar {
/// Creates a `Condvar` which is ready to be waited on and notified.
fn default() -> Condvar {
#[cfg(test)]
mod tests {
- use sync::mpsc::channel;
- use sync::{Condvar, Mutex, Arc};
- use thread;
- use time::Duration;
- use u32;
+ use crate::sync::atomic::{AtomicBool, Ordering};
+ use crate::sync::mpsc::channel;
+ use crate::sync::{Arc, Condvar, Mutex};
+ use crate::thread;
+ use crate::time::Duration;
#[test]
fn smoke() {
}
#[test]
+ #[cfg_attr(target_os = "emscripten", ignore)]
fn notify_one() {
let m = Arc::new(Mutex::new(()));
let m2 = m.clone();
let c2 = c.clone();
let g = m.lock().unwrap();
- let _t = thread::spawn(move|| {
+ let _t = thread::spawn(move || {
let _g = m2.lock().unwrap();
c2.notify_one();
});
}
#[test]
+ #[cfg_attr(target_os = "emscripten", ignore)]
fn notify_all() {
const N: usize = 10;
for _ in 0..N {
let data = data.clone();
let tx = tx.clone();
- thread::spawn(move|| {
+ thread::spawn(move || {
let &(ref lock, ref cond) = &*data;
let mut cnt = lock.lock().unwrap();
*cnt += 1;
}
#[test]
- fn wait_timeout_ms() {
+ #[cfg_attr(target_os = "emscripten", ignore)]
+ fn wait_while() {
+ let pair = Arc::new((Mutex::new(false), Condvar::new()));
+ let pair2 = pair.clone();
+
+ // Inside of our lock, spawn a new thread, and then wait for it to start.
+ thread::spawn(move || {
+ let &(ref lock, ref cvar) = &*pair2;
+ let mut started = lock.lock().unwrap();
+ *started = true;
+ // We notify the condvar that the value has changed.
+ cvar.notify_one();
+ });
+
+ // Wait for the thread to start up.
+ let &(ref lock, ref cvar) = &*pair;
+ let guard = cvar.wait_while(lock.lock().unwrap(), |started| !*started);
+ assert!(*guard.unwrap());
+ }
+
+ #[test]
+ #[cfg_attr(target_os = "emscripten", ignore)]
+ #[cfg_attr(target_env = "sgx", ignore)] // FIXME: https://github.com/fortanix/rust-sgx/issues/31
+ fn wait_timeout_wait() {
let m = Arc::new(Mutex::new(()));
- let m2 = m.clone();
let c = Arc::new(Condvar::new());
- let c2 = c.clone();
+ loop {
+ let g = m.lock().unwrap();
+ let (_g, no_timeout) = c.wait_timeout(g, Duration::from_millis(1)).unwrap();
+ // spurious wakeups mean this isn't necessarily true
+ // so execute test again, if not timeout
+ if !no_timeout.timed_out() {
+ continue;
+ }
+
+ break;
+ }
+ }
+
+ #[test]
+ #[cfg_attr(target_os = "emscripten", ignore)]
+ #[cfg_attr(target_env = "sgx", ignore)] // FIXME: https://github.com/fortanix/rust-sgx/issues/31
+ fn wait_timeout_while_wait() {
+ let m = Arc::new(Mutex::new(()));
+ let c = Arc::new(Condvar::new());
+
+ let g = m.lock().unwrap();
+ let (_g, wait) = c.wait_timeout_while(g, Duration::from_millis(1), |_| true).unwrap();
+ // no spurious wakeups. ensure it timed-out
+ assert!(wait.timed_out());
+ }
+
+ #[test]
+ #[cfg_attr(target_os = "emscripten", ignore)]
+ fn wait_timeout_while_instant_satisfy() {
+ let m = Arc::new(Mutex::new(()));
+ let c = Arc::new(Condvar::new());
+
+ let g = m.lock().unwrap();
+ let (_g, wait) = c.wait_timeout_while(g, Duration::from_millis(0), |_| false).unwrap();
+ // ensure it didn't time-out even if we were not given any time.
+ assert!(!wait.timed_out());
+ }
+
+ #[test]
+ #[cfg_attr(target_os = "emscripten", ignore)]
+ #[cfg_attr(target_env = "sgx", ignore)] // FIXME: https://github.com/fortanix/rust-sgx/issues/31
+ fn wait_timeout_while_wake() {
+ let pair = Arc::new((Mutex::new(false), Condvar::new()));
+ let pair_copy = pair.clone();
+
+ let &(ref m, ref c) = &*pair;
let g = m.lock().unwrap();
- let (g, _no_timeout) = c.wait_timeout(g, Duration::from_millis(1)).unwrap();
- // spurious wakeups mean this isn't necessarily true
- // assert!(!no_timeout);
let _t = thread::spawn(move || {
- let _g = m2.lock().unwrap();
- c2.notify_one();
+ let &(ref lock, ref cvar) = &*pair_copy;
+ let mut started = lock.lock().unwrap();
+ thread::sleep(Duration::from_millis(1));
+ *started = true;
+ cvar.notify_one();
});
- let (g, timeout_res) = c.wait_timeout(g, Duration::from_millis(u32::MAX as u64)).unwrap();
- assert!(!timeout_res.timed_out());
- drop(g);
+ let (g2, wait) = c
+ .wait_timeout_while(g, Duration::from_millis(u64::MAX), |&mut notified| !notified)
+ .unwrap();
+ // ensure it didn't time-out even if we were not given any time.
+ assert!(!wait.timed_out());
+ assert!(*g2);
+ }
+
+ #[test]
+ #[cfg_attr(target_os = "emscripten", ignore)]
+ #[cfg_attr(target_env = "sgx", ignore)] // FIXME: https://github.com/fortanix/rust-sgx/issues/31
+ fn wait_timeout_wake() {
+ let m = Arc::new(Mutex::new(()));
+ let c = Arc::new(Condvar::new());
+
+ loop {
+ let g = m.lock().unwrap();
+
+ let c2 = c.clone();
+ let m2 = m.clone();
+
+ let notified = Arc::new(AtomicBool::new(false));
+ let notified_copy = notified.clone();
+
+ let t = thread::spawn(move || {
+ let _g = m2.lock().unwrap();
+ thread::sleep(Duration::from_millis(1));
+ notified_copy.store(true, Ordering::SeqCst);
+ c2.notify_one();
+ });
+ let (g, timeout_res) = c.wait_timeout(g, Duration::from_millis(u64::MAX)).unwrap();
+ assert!(!timeout_res.timed_out());
+ // spurious wakeups mean this isn't necessarily true
+ // so execute test again, if not notified
+ if !notified.load(Ordering::SeqCst) {
+ t.join().unwrap();
+ continue;
+ }
+ drop(g);
+
+ t.join().unwrap();
+
+ break;
+ }
}
#[test]
#[should_panic]
+ #[cfg_attr(target_os = "emscripten", ignore)]
fn two_mutexes() {
let m = Arc::new(Mutex::new(()));
let m2 = m.clone();
let c2 = c.clone();
let mut g = m.lock().unwrap();
- let _t = thread::spawn(move|| {
+ let _t = thread::spawn(move || {
let _g = m2.lock().unwrap();
c2.notify_one();
});
projects / rustc.git / blobdiff