| // Copyright 2018 The Chromium OS Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| use std::fmt::{self, Debug}; |
| use std::sync::{Condvar as StdCondvar, MutexGuard, WaitTimeoutResult}; |
| use std::time::Duration; |
| |
| static CONDVAR_POISONED: &str = "condvar is poisoned"; |
| |
| /// A Condition Variable. |
| #[derive(Default)] |
| pub struct Condvar { |
| std: StdCondvar, |
| } |
| |
| impl Condvar { |
| /// Creates a new condvar that is ready to be waited on. |
| pub fn new() -> Condvar { |
| Condvar { |
| std: StdCondvar::new(), |
| } |
| } |
| |
| /// Waits on a condvar, blocking the current thread until it is notified. |
| pub fn wait<'a, T>(&self, guard: MutexGuard<'a, T>) -> MutexGuard<'a, T> { |
| self.std.wait(guard).expect(CONDVAR_POISONED) |
| } |
| |
| /// Blocks the current thread until this condition variable receives a notification and the |
| /// provided condition is false. |
| pub fn wait_while<'a, T, F>(&self, guard: MutexGuard<'a, T>, condition: F) -> MutexGuard<'a, T> |
| where |
| F: FnMut(&mut T) -> bool, |
| { |
| self.std |
| .wait_while(guard, condition) |
| .expect(CONDVAR_POISONED) |
| } |
| |
| /// Waits on a condvar, blocking the current thread until it is notified |
| /// or the specified duration has elapsed. |
| pub fn wait_timeout<'a, T>( |
| &self, |
| guard: MutexGuard<'a, T>, |
| dur: Duration, |
| ) -> (MutexGuard<'a, T>, WaitTimeoutResult) { |
| self.std.wait_timeout(guard, dur).expect(CONDVAR_POISONED) |
| } |
| |
| /// Waits on this condition variable for a notification, timing out after a specified duration. |
| pub fn wait_timeout_while<'a, T, F>( |
| &self, |
| guard: MutexGuard<'a, T>, |
| dur: Duration, |
| condition: F, |
| ) -> (MutexGuard<'a, T>, WaitTimeoutResult) |
| where |
| F: FnMut(&mut T) -> bool, |
| { |
| self.std |
| .wait_timeout_while(guard, dur, condition) |
| .expect(CONDVAR_POISONED) |
| } |
| |
| /// Notifies one thread blocked by this condvar. |
| pub fn notify_one(&self) { |
| self.std.notify_one(); |
| } |
| |
| /// Notifies all threads blocked by this condvar. |
| pub fn notify_all(&self) { |
| self.std.notify_all(); |
| } |
| } |
| |
| impl Debug for Condvar { |
| fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { |
| Debug::fmt(&self.std, formatter) |
| } |
| } |