2013-05-20 05:06:37 -05:00
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// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
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2012-12-03 18:48:01 -06:00
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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2013-05-20 05:07:14 -05:00
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/*!
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2012-08-10 17:20:03 -05:00
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* Concurrency-enabled mechanisms for sharing mutable and/or immutable state
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* between tasks.
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*
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* # Example
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*
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* In this example, a large vector of floats is shared between several tasks.
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* With simple pipes, without ARC, a copy would have to be made for each task.
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*
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2013-05-27 08:49:54 -05:00
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* ~~~ {.rust}
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* extern mod std;
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* use std::arc;
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* let numbers=vec::from_fn(100, |ind| (ind as float)*rand::random());
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* let shared_numbers=arc::ARC(numbers);
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*
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* for 10.times {
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* let (port, chan) = stream();
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* chan.send(shared_numbers.clone());
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*
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* do spawn {
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* let shared_numbers=port.recv();
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* let local_numbers=shared_numbers.get();
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*
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* // Work with the local numbers
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* }
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* }
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* ~~~
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2012-08-10 17:20:03 -05:00
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*/
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2013-05-28 22:11:41 -05:00
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#[allow(missing_doc)];
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2013-05-17 17:28:44 -05:00
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use core::prelude::*;
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2012-12-23 16:41:37 -06:00
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use sync;
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use sync::{Mutex, mutex_with_condvars, RWlock, rwlock_with_condvars};
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2012-12-23 16:41:37 -06:00
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use core::cast;
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use core::unstable::sync::UnsafeAtomicRcBox;
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use core::task;
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use core::borrow;
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2012-08-13 18:45:17 -05:00
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2013-05-20 05:06:37 -05:00
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/// As sync::condvar, a mechanism for unlock-and-descheduling and signaling.
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2013-03-22 17:52:50 -05:00
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pub struct Condvar<'self> {
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is_mutex: bool,
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failed: &'self mut bool,
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cond: &'self sync::Condvar<'self>
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}
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2013-05-31 17:17:22 -05:00
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impl<'self> Condvar<'self> {
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/// Atomically exit the associated ARC and block until a signal is sent.
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#[inline(always)]
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pub fn wait(&self) { self.wait_on(0) }
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2012-08-14 22:35:12 -05:00
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/**
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* Atomically exit the associated ARC and block on a specified condvar
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* until a signal is sent on that same condvar (as sync::cond.wait_on).
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*
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* wait() is equivalent to wait_on(0).
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*/
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#[inline(always)]
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pub fn wait_on(&self, condvar_id: uint) {
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assert!(!*self.failed);
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self.cond.wait_on(condvar_id);
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2012-08-13 18:45:17 -05:00
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// This is why we need to wrap sync::condvar.
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check_poison(self.is_mutex, *self.failed);
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}
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2013-02-26 13:34:00 -06:00
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2012-08-13 18:45:17 -05:00
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/// Wake up a blocked task. Returns false if there was no blocked task.
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#[inline(always)]
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pub fn signal(&self) -> bool { self.signal_on(0) }
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2012-08-14 22:35:12 -05:00
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/**
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* Wake up a blocked task on a specified condvar (as
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* sync::cond.signal_on). Returns false if there was no blocked task.
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*/
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#[inline(always)]
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pub fn signal_on(&self, condvar_id: uint) -> bool {
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assert!(!*self.failed);
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self.cond.signal_on(condvar_id)
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}
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2013-02-26 13:34:00 -06:00
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2012-08-13 18:45:17 -05:00
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/// Wake up all blocked tasks. Returns the number of tasks woken.
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#[inline(always)]
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pub fn broadcast(&self) -> uint { self.broadcast_on(0) }
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2012-08-14 22:35:12 -05:00
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/**
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* Wake up all blocked tasks on a specified condvar (as
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2013-06-06 02:38:41 -05:00
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* sync::cond.broadcast_on). Returns the number of tasks woken.
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2012-08-14 22:35:12 -05:00
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*/
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#[inline(always)]
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pub fn broadcast_on(&self, condvar_id: uint) -> uint {
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assert!(!*self.failed);
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self.cond.broadcast_on(condvar_id)
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2012-08-13 18:45:17 -05:00
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}
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}
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2012-08-10 17:20:03 -05:00
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/****************************************************************************
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* Immutable ARC
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****************************************************************************/
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/// An atomically reference counted wrapper for shared immutable state.
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2013-05-24 14:38:12 -05:00
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pub struct ARC<T> { x: UnsafeAtomicRcBox<T> }
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/// Create an atomically reference counted wrapper.
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pub fn ARC<T:Const + Owned>(data: T) -> ARC<T> {
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ARC { x: UnsafeAtomicRcBox::new(data) }
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}
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/**
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* Access the underlying data in an atomically reference counted
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* wrapper.
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*/
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2013-05-31 17:17:22 -05:00
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impl<T:Const+Owned> ARC<T> {
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pub fn get<'a>(&'a self) -> &'a T {
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unsafe { &*self.x.get_immut() }
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}
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}
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2013-05-24 15:54:58 -05:00
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2012-08-10 17:20:03 -05:00
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/**
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* Duplicate an atomically reference counted wrapper.
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*
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* The resulting two `arc` objects will point to the same underlying data
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* object. However, one of the `arc` objects can be sent to another task,
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* allowing them to share the underlying data.
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*/
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impl<T:Const + Owned> Clone for ARC<T> {
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fn clone(&self) -> ARC<T> {
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ARC { x: self.x.clone() }
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}
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}
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2012-08-10 17:20:03 -05:00
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/****************************************************************************
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* Mutex protected ARC (unsafe)
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****************************************************************************/
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2012-08-15 12:55:20 -05:00
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#[doc(hidden)]
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struct MutexARCInner<T> { lock: Mutex, failed: bool, data: T }
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/// An ARC with mutable data protected by a blocking mutex.
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struct MutexARC<T> { x: UnsafeAtomicRcBox<MutexARCInner<T>> }
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/// Create a mutex-protected ARC with the supplied data.
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pub fn MutexARC<T:Owned>(user_data: T) -> MutexARC<T> {
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mutex_arc_with_condvars(user_data, 1)
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}
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/**
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* Create a mutex-protected ARC with the supplied data and a specified number
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* of condvars (as sync::mutex_with_condvars).
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*/
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pub fn mutex_arc_with_condvars<T:Owned>(user_data: T,
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num_condvars: uint) -> MutexARC<T> {
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let data =
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MutexARCInner { lock: mutex_with_condvars(num_condvars),
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failed: false, data: user_data };
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MutexARC { x: UnsafeAtomicRcBox::new(data) }
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}
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2013-02-20 19:07:17 -06:00
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impl<T:Owned> Clone for MutexARC<T> {
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/// Duplicate a mutex-protected ARC, as arc::clone.
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fn clone(&self) -> MutexARC<T> {
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// NB: Cloning the underlying mutex is not necessary. Its reference
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// count would be exactly the same as the shared state's.
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MutexARC { x: self.x.clone() }
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}
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}
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2013-05-31 17:17:22 -05:00
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impl<T:Owned> MutexARC<T> {
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2012-08-10 19:46:19 -05:00
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/**
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* Access the underlying mutable data with mutual exclusion from other
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* tasks. The argument closure will be run with the mutex locked; all
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* other tasks wishing to access the data will block until the closure
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* finishes running.
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*
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* The reason this function is 'unsafe' is because it is possible to
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* construct a circular reference among multiple ARCs by mutating the
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* underlying data. This creates potential for deadlock, but worse, this
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* will guarantee a memory leak of all involved ARCs. Using mutex ARCs
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* inside of other ARCs is safe in absence of circular references.
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*
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* If you wish to nest mutex_arcs, one strategy for ensuring safety at
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* runtime is to add a "nesting level counter" inside the stored data, and
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* when traversing the arcs, assert that they monotonically decrease.
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*
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* # Failure
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*
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* Failing while inside the ARC will unlock the ARC while unwinding, so
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* that other tasks won't block forever. It will also poison the ARC:
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* any tasks that subsequently try to access it (including those already
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* blocked on the mutex) will also fail immediately.
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*/
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#[inline(always)]
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pub unsafe fn access<U>(&self, blk: &fn(x: &mut T) -> U) -> U {
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unsafe {
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let state = self.x.get();
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// Borrowck would complain about this if the function were
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// not already unsafe. See borrow_rwlock, far below.
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do (&(*state).lock).lock {
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check_poison(true, (*state).failed);
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let _z = PoisonOnFail(&mut (*state).failed);
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blk(&mut (*state).data)
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}
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2012-08-10 19:46:19 -05:00
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}
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}
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2013-02-26 13:34:00 -06:00
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2012-08-10 19:46:19 -05:00
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/// As access(), but with a condvar, as sync::mutex.lock_cond().
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#[inline(always)]
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pub unsafe fn access_cond<'x, 'c, U>(&self,
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blk: &fn(x: &'x mut T,
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c: &'c Condvar) -> U)
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-> U {
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let state = self.x.get();
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2013-04-23 18:33:33 -05:00
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do (&(*state).lock).lock_cond |cond| {
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check_poison(true, (*state).failed);
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let _z = PoisonOnFail(&mut (*state).failed);
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blk(&mut (*state).data,
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&Condvar {is_mutex: true,
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failed: &mut (*state).failed,
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cond: cond })
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2012-08-10 19:46:19 -05:00
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}
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}
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}
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// Common code for {mutex.access,rwlock.write}{,_cond}.
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#[inline(always)]
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#[doc(hidden)]
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fn check_poison(is_mutex: bool, failed: bool) {
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if failed {
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if is_mutex {
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fail!("Poisoned MutexARC - another task failed inside!");
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} else {
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fail!("Poisoned rw_arc - another task failed inside!");
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2012-08-10 19:46:19 -05:00
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}
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}
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}
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2012-08-15 12:55:20 -05:00
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#[doc(hidden)]
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2012-08-26 20:28:36 -05:00
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struct PoisonOnFail {
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failed: *mut bool,
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}
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2013-02-14 13:47:00 -06:00
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impl Drop for PoisonOnFail {
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fn finalize(&self) {
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unsafe {
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2013-03-28 20:39:09 -05:00
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/* assert!(!*self.failed);
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-- might be false in case of cond.wait() */
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if task::failing() {
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*self.failed = true;
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}
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}
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2012-08-13 18:45:17 -05:00
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}
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}
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2013-03-25 15:21:04 -05:00
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fn PoisonOnFail<'r>(failed: &'r mut bool) -> PoisonOnFail {
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PoisonOnFail {
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failed: failed
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}
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}
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2012-08-10 17:20:03 -05:00
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/****************************************************************************
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* R/W lock protected ARC
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****************************************************************************/
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2012-08-15 12:55:20 -05:00
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#[doc(hidden)]
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struct RWARCInner<T> { lock: RWlock, failed: bool, data: T }
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2012-08-10 19:46:19 -05:00
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/**
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* A dual-mode ARC protected by a reader-writer lock. The data can be accessed
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* mutably or immutably, and immutably-accessing tasks may run concurrently.
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*
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* Unlike mutex_arcs, rw_arcs are safe, because they cannot be nested.
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|
|
|
*/
|
2013-05-07 12:00:00 -05:00
|
|
|
#[mutable]
|
2013-01-28 12:46:43 -06:00
|
|
|
struct RWARC<T> {
|
2013-05-09 22:27:42 -05:00
|
|
|
x: UnsafeAtomicRcBox<RWARCInner<T>>,
|
2013-03-24 11:41:19 -05:00
|
|
|
cant_nest: ()
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
|
|
|
|
/// Create a reader/writer ARC with the supplied data.
|
2013-02-20 19:07:17 -06:00
|
|
|
pub fn RWARC<T:Const + Owned>(user_data: T) -> RWARC<T> {
|
2013-02-15 01:30:30 -06:00
|
|
|
rw_arc_with_condvars(user_data, 1)
|
2012-08-14 22:35:12 -05:00
|
|
|
}
|
|
|
|
/**
|
|
|
|
* Create a reader/writer ARC with the supplied data and a specified number
|
|
|
|
* of condvars (as sync::rwlock_with_condvars).
|
|
|
|
*/
|
2013-02-20 19:07:17 -06:00
|
|
|
pub fn rw_arc_with_condvars<T:Const + Owned>(
|
2013-02-09 00:21:45 -06:00
|
|
|
user_data: T,
|
|
|
|
num_condvars: uint) -> RWARC<T>
|
|
|
|
{
|
2012-08-14 22:35:12 -05:00
|
|
|
let data =
|
2012-08-26 20:28:36 -05:00
|
|
|
RWARCInner { lock: rwlock_with_condvars(num_condvars),
|
2013-02-15 01:30:30 -06:00
|
|
|
failed: false, data: user_data };
|
2013-05-09 22:27:42 -05:00
|
|
|
RWARC { x: UnsafeAtomicRcBox::new(data), cant_nest: () }
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
|
2013-05-31 17:17:22 -05:00
|
|
|
impl<T:Const + Owned> RWARC<T> {
|
2012-08-10 19:46:19 -05:00
|
|
|
/// Duplicate a rwlock-protected ARC, as arc::clone.
|
2013-05-31 17:17:22 -05:00
|
|
|
pub fn clone(&self) -> RWARC<T> {
|
|
|
|
RWARC {
|
|
|
|
x: self.x.clone(),
|
|
|
|
cant_nest: (),
|
|
|
|
}
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
|
2012-11-26 18:12:47 -06:00
|
|
|
}
|
|
|
|
|
2013-05-31 17:17:22 -05:00
|
|
|
impl<T:Const + Owned> RWARC<T> {
|
2012-08-10 19:46:19 -05:00
|
|
|
/**
|
|
|
|
* Access the underlying data mutably. Locks the rwlock in write mode;
|
|
|
|
* other readers and writers will block.
|
|
|
|
*
|
|
|
|
* # Failure
|
|
|
|
*
|
|
|
|
* Failing while inside the ARC will unlock the ARC while unwinding, so
|
2012-08-26 20:28:36 -05:00
|
|
|
* that other tasks won't block forever. As MutexARC.access, it will also
|
2012-08-10 19:46:19 -05:00
|
|
|
* poison the ARC, so subsequent readers and writers will both also fail.
|
|
|
|
*/
|
|
|
|
#[inline(always)]
|
2013-05-31 17:17:22 -05:00
|
|
|
pub fn write<U>(&self, blk: &fn(x: &mut T) -> U) -> U {
|
2013-02-09 00:21:45 -06:00
|
|
|
unsafe {
|
2013-05-09 22:27:42 -05:00
|
|
|
let state = self.x.get();
|
2013-02-09 00:21:45 -06:00
|
|
|
do (*borrow_rwlock(state)).write {
|
|
|
|
check_poison(false, (*state).failed);
|
|
|
|
let _z = PoisonOnFail(&mut (*state).failed);
|
|
|
|
blk(&mut (*state).data)
|
|
|
|
}
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
}
|
2013-05-31 17:17:22 -05:00
|
|
|
|
2012-08-10 19:46:19 -05:00
|
|
|
/// As write(), but with a condvar, as sync::rwlock.write_cond().
|
|
|
|
#[inline(always)]
|
2013-05-31 17:17:22 -05:00
|
|
|
pub fn write_cond<'x, 'c, U>(&self,
|
|
|
|
blk: &fn(x: &'x mut T, c: &'c Condvar) -> U)
|
|
|
|
-> U {
|
2013-02-09 00:21:45 -06:00
|
|
|
unsafe {
|
2013-05-09 22:27:42 -05:00
|
|
|
let state = self.x.get();
|
2013-02-09 00:21:45 -06:00
|
|
|
do (*borrow_rwlock(state)).write_cond |cond| {
|
|
|
|
check_poison(false, (*state).failed);
|
|
|
|
let _z = PoisonOnFail(&mut (*state).failed);
|
|
|
|
blk(&mut (*state).data,
|
|
|
|
&Condvar {is_mutex: false,
|
|
|
|
failed: &mut (*state).failed,
|
|
|
|
cond: cond})
|
|
|
|
}
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
}
|
2013-05-31 17:17:22 -05:00
|
|
|
|
2012-08-10 19:46:19 -05:00
|
|
|
/**
|
|
|
|
* Access the underlying data immutably. May run concurrently with other
|
|
|
|
* reading tasks.
|
|
|
|
*
|
|
|
|
* # Failure
|
|
|
|
*
|
|
|
|
* Failing will unlock the ARC while unwinding. However, unlike all other
|
|
|
|
* access modes, this will not poison the ARC.
|
|
|
|
*/
|
2013-05-31 17:17:22 -05:00
|
|
|
pub fn read<U>(&self, blk: &fn(x: &T) -> U) -> U {
|
2013-05-09 22:27:42 -05:00
|
|
|
unsafe {
|
2013-05-23 21:12:16 -05:00
|
|
|
let state = self.x.get();
|
2013-05-09 22:27:42 -05:00
|
|
|
do (*state).lock.read {
|
|
|
|
check_poison(false, (*state).failed);
|
|
|
|
blk(&(*state).data)
|
|
|
|
}
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
}
|
2012-08-14 12:32:41 -05:00
|
|
|
|
|
|
|
/**
|
|
|
|
* As write(), but with the ability to atomically 'downgrade' the lock.
|
2012-08-26 20:28:36 -05:00
|
|
|
* See sync::rwlock.write_downgrade(). The RWWriteMode token must be used
|
|
|
|
* to obtain the &mut T, and can be transformed into a RWReadMode token by
|
|
|
|
* calling downgrade(), after which a &T can be obtained instead.
|
2013-05-27 08:49:54 -05:00
|
|
|
*
|
|
|
|
* # Example
|
|
|
|
*
|
|
|
|
* ~~~ {.rust}
|
2012-08-14 12:32:41 -05:00
|
|
|
* do arc.write_downgrade |write_mode| {
|
|
|
|
* do (&write_mode).write_cond |state, condvar| {
|
|
|
|
* ... exclusive access with mutable state ...
|
|
|
|
* }
|
|
|
|
* let read_mode = arc.downgrade(write_mode);
|
|
|
|
* do (&read_mode).read |state| {
|
|
|
|
* ... shared access with immutable state ...
|
|
|
|
* }
|
|
|
|
* }
|
|
|
|
* ~~~
|
|
|
|
*/
|
2013-05-31 17:17:22 -05:00
|
|
|
pub fn write_downgrade<U>(&self, blk: &fn(v: RWWriteMode<T>) -> U) -> U {
|
2013-02-09 00:21:45 -06:00
|
|
|
unsafe {
|
2013-05-09 22:27:42 -05:00
|
|
|
let state = self.x.get();
|
2013-02-09 00:21:45 -06:00
|
|
|
do (*borrow_rwlock(state)).write_downgrade |write_mode| {
|
|
|
|
check_poison(false, (*state).failed);
|
2013-03-07 19:23:14 -06:00
|
|
|
blk(RWWriteMode {
|
|
|
|
data: &mut (*state).data,
|
|
|
|
token: write_mode,
|
|
|
|
poison: PoisonOnFail(&mut (*state).failed)
|
|
|
|
})
|
2013-02-09 00:21:45 -06:00
|
|
|
}
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/// To be called inside of the write_downgrade block.
|
2013-05-31 17:17:22 -05:00
|
|
|
pub fn downgrade<'a>(&self, token: RWWriteMode<'a, T>)
|
|
|
|
-> RWReadMode<'a, T> {
|
2013-05-09 22:27:42 -05:00
|
|
|
unsafe {
|
|
|
|
// The rwlock should assert that the token belongs to us for us.
|
|
|
|
let state = self.x.get();
|
|
|
|
let RWWriteMode {
|
|
|
|
data: data,
|
|
|
|
token: t,
|
|
|
|
poison: _poison
|
|
|
|
} = token;
|
|
|
|
// Let readers in
|
|
|
|
let new_token = (*state).lock.downgrade(t);
|
|
|
|
// Whatever region the input reference had, it will be safe to use
|
|
|
|
// the same region for the output reference. (The only 'unsafe' part
|
|
|
|
// of this cast is removing the mutability.)
|
|
|
|
let new_data = cast::transmute_immut(data);
|
|
|
|
// Downgrade ensured the token belonged to us. Just a sanity check.
|
2013-06-02 18:16:40 -05:00
|
|
|
assert!(borrow::ref_eq(&(*state).data, new_data));
|
2013-05-09 22:27:42 -05:00
|
|
|
// Produce new token
|
|
|
|
RWReadMode {
|
|
|
|
data: new_data,
|
|
|
|
token: new_token,
|
|
|
|
}
|
2013-03-07 19:23:14 -06:00
|
|
|
}
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
|
|
|
|
// Borrowck rightly complains about immutably aliasing the rwlock in order to
|
|
|
|
// lock it. This wraps the unsafety, with the justification that the 'lock'
|
|
|
|
// field is never overwritten; only 'failed' and 'data'.
|
2012-08-15 12:55:20 -05:00
|
|
|
#[doc(hidden)]
|
2013-02-20 19:07:17 -06:00
|
|
|
fn borrow_rwlock<T:Const + Owned>(state: *const RWARCInner<T>) -> *RWlock {
|
2013-02-09 00:21:45 -06:00
|
|
|
unsafe { cast::transmute(&const (*state).lock) }
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
|
2012-08-26 20:28:36 -05:00
|
|
|
/// The "write permission" token used for RWARC.write_downgrade().
|
2013-03-07 19:23:14 -06:00
|
|
|
pub struct RWWriteMode<'self, T> {
|
|
|
|
data: &'self mut T,
|
|
|
|
token: sync::RWlockWriteMode<'self>,
|
|
|
|
poison: PoisonOnFail,
|
|
|
|
}
|
|
|
|
|
2012-08-26 20:28:36 -05:00
|
|
|
/// The "read permission" token used for RWARC.write_downgrade().
|
2013-03-07 19:23:14 -06:00
|
|
|
pub struct RWReadMode<'self, T> {
|
|
|
|
data: &'self T,
|
|
|
|
token: sync::RWlockReadMode<'self>,
|
|
|
|
}
|
2012-08-14 12:32:41 -05:00
|
|
|
|
2013-05-31 17:17:22 -05:00
|
|
|
impl<'self, T:Const + Owned> RWWriteMode<'self, T> {
|
2012-08-26 20:28:36 -05:00
|
|
|
/// Access the pre-downgrade RWARC in write mode.
|
2013-05-31 17:17:22 -05:00
|
|
|
pub fn write<U>(&mut self, blk: &fn(x: &mut T) -> U) -> U {
|
2012-08-14 12:32:41 -05:00
|
|
|
match *self {
|
2013-03-07 19:23:14 -06:00
|
|
|
RWWriteMode {
|
2013-03-15 14:24:24 -05:00
|
|
|
data: &ref mut data,
|
2013-03-07 19:23:14 -06:00
|
|
|
token: ref token,
|
|
|
|
poison: _
|
|
|
|
} => {
|
2012-08-23 15:51:53 -05:00
|
|
|
do token.write {
|
2013-03-15 14:24:24 -05:00
|
|
|
blk(data)
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
2013-05-31 17:17:22 -05:00
|
|
|
|
2012-08-26 20:28:36 -05:00
|
|
|
/// Access the pre-downgrade RWARC in write mode with a condvar.
|
2013-05-31 17:17:22 -05:00
|
|
|
pub fn write_cond<'x, 'c, U>(&mut self,
|
|
|
|
blk: &fn(x: &'x mut T, c: &'c Condvar) -> U)
|
|
|
|
-> U {
|
2012-08-14 12:32:41 -05:00
|
|
|
match *self {
|
2013-03-07 19:23:14 -06:00
|
|
|
RWWriteMode {
|
2013-03-15 14:24:24 -05:00
|
|
|
data: &ref mut data,
|
2013-03-07 19:23:14 -06:00
|
|
|
token: ref token,
|
|
|
|
poison: ref poison
|
|
|
|
} => {
|
2012-08-23 15:51:53 -05:00
|
|
|
do token.write_cond |cond| {
|
2013-01-23 20:15:06 -06:00
|
|
|
unsafe {
|
|
|
|
let cvar = Condvar {
|
|
|
|
is_mutex: false,
|
|
|
|
failed: &mut *poison.failed,
|
|
|
|
cond: cond
|
|
|
|
};
|
2013-03-15 14:24:24 -05:00
|
|
|
blk(data, &cvar)
|
2013-01-23 20:15:06 -06:00
|
|
|
}
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2013-05-31 17:17:22 -05:00
|
|
|
impl<'self, T:Const + Owned> RWReadMode<'self, T> {
|
2012-08-14 12:32:41 -05:00
|
|
|
/// Access the post-downgrade rwlock in read mode.
|
2013-05-31 17:17:22 -05:00
|
|
|
pub fn read<U>(&self, blk: &fn(x: &T) -> U) -> U {
|
2012-08-14 12:32:41 -05:00
|
|
|
match *self {
|
2013-03-07 19:23:14 -06:00
|
|
|
RWReadMode {
|
|
|
|
data: data,
|
|
|
|
token: ref token
|
|
|
|
} => {
|
2012-08-23 15:51:53 -05:00
|
|
|
do token.read { blk(data) }
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2012-08-10 17:20:03 -05:00
|
|
|
/****************************************************************************
|
|
|
|
* Tests
|
|
|
|
****************************************************************************/
|
|
|
|
|
|
|
|
#[cfg(test)]
|
|
|
|
mod tests {
|
2013-05-21 19:24:31 -05:00
|
|
|
use core::prelude::*;
|
2013-05-24 21:35:29 -05:00
|
|
|
|
2013-01-08 21:37:25 -06:00
|
|
|
use arc::*;
|
2012-12-28 14:46:08 -06:00
|
|
|
|
2013-05-24 21:35:29 -05:00
|
|
|
use core::cell::Cell;
|
|
|
|
use core::comm;
|
|
|
|
use core::task;
|
|
|
|
|
2012-08-10 17:20:03 -05:00
|
|
|
#[test]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn manually_share_arc() {
|
2012-08-10 17:20:03 -05:00
|
|
|
let v = ~[1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
|
2013-05-24 14:38:12 -05:00
|
|
|
let arc_v = ARC(v);
|
2012-08-10 17:20:03 -05:00
|
|
|
|
2013-02-02 05:10:12 -06:00
|
|
|
let (p, c) = comm::stream();
|
2012-08-10 17:20:03 -05:00
|
|
|
|
2013-02-15 01:30:30 -06:00
|
|
|
do task::spawn() || {
|
2013-04-17 01:45:29 -05:00
|
|
|
let p = comm::PortSet::new();
|
2012-08-14 16:17:27 -05:00
|
|
|
c.send(p.chan());
|
2012-08-10 17:20:03 -05:00
|
|
|
|
2013-05-24 14:38:12 -05:00
|
|
|
let arc_v : ARC<~[int]> = p.recv();
|
2012-08-10 17:20:03 -05:00
|
|
|
|
2013-05-24 14:38:12 -05:00
|
|
|
let v = copy (*arc_v.get());
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(v[3], 4);
|
2012-08-10 17:20:03 -05:00
|
|
|
};
|
|
|
|
|
|
|
|
let c = p.recv();
|
2013-05-24 14:38:12 -05:00
|
|
|
c.send(arc_v.clone());
|
2012-08-10 17:20:03 -05:00
|
|
|
|
2013-05-24 14:38:12 -05:00
|
|
|
assert_eq!(arc_v.get()[2], 3);
|
2013-05-20 05:07:14 -05:00
|
|
|
assert_eq!(arc_v.get()[4], 5);
|
2012-08-10 17:20:03 -05:00
|
|
|
|
2013-03-08 14:39:42 -06:00
|
|
|
info!(arc_v);
|
2012-08-10 17:20:03 -05:00
|
|
|
}
|
2012-08-10 19:46:19 -05:00
|
|
|
|
2012-08-13 18:45:17 -05:00
|
|
|
#[test]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_mutex_arc_condvar() {
|
2013-05-24 21:35:29 -05:00
|
|
|
unsafe {
|
|
|
|
let arc = ~MutexARC(false);
|
|
|
|
let arc2 = ~arc.clone();
|
|
|
|
let (p,c) = comm::oneshot();
|
2013-06-04 05:03:58 -05:00
|
|
|
let (c,p) = (Cell::new(c), Cell::new(p));
|
2013-05-24 21:35:29 -05:00
|
|
|
do task::spawn || {
|
|
|
|
// wait until parent gets in
|
|
|
|
comm::recv_one(p.take());
|
|
|
|
do arc2.access_cond |state, cond| {
|
|
|
|
*state = true;
|
|
|
|
cond.signal();
|
|
|
|
}
|
2012-08-13 18:45:17 -05:00
|
|
|
}
|
2013-05-24 21:35:29 -05:00
|
|
|
do arc.access_cond |state, cond| {
|
|
|
|
comm::send_one(c.take(), ());
|
|
|
|
assert!(!*state);
|
|
|
|
while !*state {
|
|
|
|
cond.wait();
|
|
|
|
}
|
2012-08-13 18:45:17 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
#[test] #[should_fail] #[ignore(cfg(windows))]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_arc_condvar_poison() {
|
2013-05-24 21:35:29 -05:00
|
|
|
unsafe {
|
|
|
|
let arc = ~MutexARC(1);
|
|
|
|
let arc2 = ~arc.clone();
|
|
|
|
let (p, c) = comm::stream();
|
|
|
|
|
|
|
|
do task::spawn_unlinked || {
|
|
|
|
let _ = p.recv();
|
|
|
|
do arc2.access_cond |one, cond| {
|
|
|
|
cond.signal();
|
|
|
|
// Parent should fail when it wakes up.
|
|
|
|
assert_eq!(*one, 0);
|
|
|
|
}
|
2012-08-13 18:45:17 -05:00
|
|
|
}
|
|
|
|
|
2013-05-24 21:35:29 -05:00
|
|
|
do arc.access_cond |one, cond| {
|
|
|
|
c.send(());
|
|
|
|
while *one == 1 {
|
|
|
|
cond.wait();
|
|
|
|
}
|
2012-08-13 18:45:17 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
2012-08-10 19:46:19 -05:00
|
|
|
#[test] #[should_fail] #[ignore(cfg(windows))]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_mutex_arc_poison() {
|
2013-05-24 21:35:29 -05:00
|
|
|
unsafe {
|
|
|
|
let arc = ~MutexARC(1);
|
|
|
|
let arc2 = ~arc.clone();
|
|
|
|
do task::try || {
|
|
|
|
do arc2.access |one| {
|
|
|
|
assert_eq!(*one, 2);
|
|
|
|
}
|
|
|
|
};
|
|
|
|
do arc.access |one| {
|
|
|
|
assert_eq!(*one, 1);
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
#[test] #[should_fail] #[ignore(cfg(windows))]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_rw_arc_poison_wr() {
|
2012-08-29 16:45:25 -05:00
|
|
|
let arc = ~RWARC(1);
|
2013-03-15 17:26:59 -05:00
|
|
|
let arc2 = (*arc).clone();
|
2013-02-15 01:30:30 -06:00
|
|
|
do task::try || {
|
2012-08-10 19:46:19 -05:00
|
|
|
do arc2.write |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 2);
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
};
|
|
|
|
do arc.read |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 1);
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
#[test] #[should_fail] #[ignore(cfg(windows))]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_rw_arc_poison_ww() {
|
2012-08-29 16:45:25 -05:00
|
|
|
let arc = ~RWARC(1);
|
2013-03-15 17:26:59 -05:00
|
|
|
let arc2 = (*arc).clone();
|
2013-02-15 01:30:30 -06:00
|
|
|
do task::try || {
|
2012-08-10 19:46:19 -05:00
|
|
|
do arc2.write |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 2);
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
};
|
|
|
|
do arc.write |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 1);
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
}
|
2012-08-14 12:32:41 -05:00
|
|
|
#[test] #[should_fail] #[ignore(cfg(windows))]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_rw_arc_poison_dw() {
|
2012-08-29 16:45:25 -05:00
|
|
|
let arc = ~RWARC(1);
|
2013-03-15 17:26:59 -05:00
|
|
|
let arc2 = (*arc).clone();
|
2013-02-15 01:30:30 -06:00
|
|
|
do task::try || {
|
2013-05-01 07:49:48 -05:00
|
|
|
do arc2.write_downgrade |mut write_mode| {
|
|
|
|
do write_mode.write |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 2);
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
};
|
|
|
|
do arc.write |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 1);
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
2012-08-10 19:46:19 -05:00
|
|
|
#[test] #[ignore(cfg(windows))]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_rw_arc_no_poison_rr() {
|
2012-08-29 16:45:25 -05:00
|
|
|
let arc = ~RWARC(1);
|
2013-03-15 17:26:59 -05:00
|
|
|
let arc2 = (*arc).clone();
|
2013-02-15 01:30:30 -06:00
|
|
|
do task::try || {
|
2012-08-10 19:46:19 -05:00
|
|
|
do arc2.read |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 2);
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
};
|
|
|
|
do arc.read |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 1);
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
#[test] #[ignore(cfg(windows))]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_rw_arc_no_poison_rw() {
|
2012-08-29 16:45:25 -05:00
|
|
|
let arc = ~RWARC(1);
|
2013-03-15 17:26:59 -05:00
|
|
|
let arc2 = (*arc).clone();
|
2013-02-15 01:30:30 -06:00
|
|
|
do task::try || {
|
2012-08-10 19:46:19 -05:00
|
|
|
do arc2.read |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 2);
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
};
|
|
|
|
do arc.write |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 1);
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
}
|
2012-08-14 12:32:41 -05:00
|
|
|
#[test] #[ignore(cfg(windows))]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_rw_arc_no_poison_dr() {
|
2012-08-29 16:45:25 -05:00
|
|
|
let arc = ~RWARC(1);
|
2013-03-15 17:26:59 -05:00
|
|
|
let arc2 = (*arc).clone();
|
2013-02-15 01:30:30 -06:00
|
|
|
do task::try || {
|
2012-08-14 12:32:41 -05:00
|
|
|
do arc2.write_downgrade |write_mode| {
|
2013-02-15 01:30:30 -06:00
|
|
|
let read_mode = arc2.downgrade(write_mode);
|
2012-08-23 15:51:53 -05:00
|
|
|
do (&read_mode).read |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 2);
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
};
|
|
|
|
do arc.write |one| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*one, 1);
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
2012-08-10 19:46:19 -05:00
|
|
|
#[test]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_rw_arc() {
|
2012-08-29 16:45:25 -05:00
|
|
|
let arc = ~RWARC(0);
|
2013-03-15 17:26:59 -05:00
|
|
|
let arc2 = (*arc).clone();
|
2013-02-02 05:10:12 -06:00
|
|
|
let (p,c) = comm::stream();
|
2012-08-10 19:46:19 -05:00
|
|
|
|
2013-02-15 01:30:30 -06:00
|
|
|
do task::spawn || {
|
2012-08-10 19:46:19 -05:00
|
|
|
do arc2.write |num| {
|
|
|
|
for 10.times {
|
|
|
|
let tmp = *num;
|
|
|
|
*num = -1;
|
|
|
|
task::yield();
|
|
|
|
*num = tmp + 1;
|
|
|
|
}
|
|
|
|
c.send(());
|
|
|
|
}
|
|
|
|
}
|
2012-09-18 23:41:37 -05:00
|
|
|
|
2012-08-10 19:46:19 -05:00
|
|
|
// Readers try to catch the writer in the act
|
|
|
|
let mut children = ~[];
|
|
|
|
for 5.times {
|
2013-03-15 17:26:59 -05:00
|
|
|
let arc3 = (*arc).clone();
|
2013-05-07 19:57:58 -05:00
|
|
|
let mut builder = task::task();
|
|
|
|
builder.future_result(|r| children.push(r));
|
|
|
|
do builder.spawn {
|
2012-08-10 19:46:19 -05:00
|
|
|
do arc3.read |num| {
|
2013-03-28 20:39:09 -05:00
|
|
|
assert!(*num >= 0);
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
2012-09-18 23:41:37 -05:00
|
|
|
|
2012-08-10 19:46:19 -05:00
|
|
|
// Wait for children to pass their asserts
|
2013-05-08 03:49:00 -05:00
|
|
|
for children.each |r| {
|
2013-05-07 19:57:58 -05:00
|
|
|
r.recv();
|
|
|
|
}
|
2012-09-18 23:41:37 -05:00
|
|
|
|
2012-08-10 19:46:19 -05:00
|
|
|
// Wait for writer to finish
|
|
|
|
p.recv();
|
2013-05-07 19:57:58 -05:00
|
|
|
do arc.read |num| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*num, 10);
|
2013-05-07 19:57:58 -05:00
|
|
|
}
|
2012-08-10 19:46:19 -05:00
|
|
|
}
|
2012-08-14 12:32:41 -05:00
|
|
|
#[test]
|
2013-04-15 10:08:52 -05:00
|
|
|
fn test_rw_downgrade() {
|
2012-08-14 12:32:41 -05:00
|
|
|
// (1) A downgrader gets in write mode and does cond.wait.
|
|
|
|
// (2) A writer gets in write mode, sets state to 42, and does signal.
|
|
|
|
// (3) Downgrader wakes, sets state to 31337.
|
|
|
|
// (4) tells writer and all other readers to contend as it downgrades.
|
|
|
|
// (5) Writer attempts to set state back to 42, while downgraded task
|
|
|
|
// and all reader tasks assert that it's 31337.
|
2012-08-29 16:45:25 -05:00
|
|
|
let arc = ~RWARC(0);
|
2012-08-14 12:32:41 -05:00
|
|
|
|
|
|
|
// Reader tasks
|
|
|
|
let mut reader_convos = ~[];
|
|
|
|
for 10.times {
|
2013-02-02 05:10:12 -06:00
|
|
|
let ((rp1,rc1),(rp2,rc2)) = (comm::stream(),comm::stream());
|
2013-02-15 01:30:30 -06:00
|
|
|
reader_convos.push((rc1, rp2));
|
2013-03-15 17:26:59 -05:00
|
|
|
let arcn = (*arc).clone();
|
2013-02-15 01:30:30 -06:00
|
|
|
do task::spawn || {
|
2012-08-14 12:32:41 -05:00
|
|
|
rp1.recv(); // wait for downgrader to give go-ahead
|
|
|
|
do arcn.read |state| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*state, 31337);
|
2012-08-14 12:32:41 -05:00
|
|
|
rc2.send(());
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// Writer task
|
2013-03-15 17:26:59 -05:00
|
|
|
let arc2 = (*arc).clone();
|
2013-02-02 05:10:12 -06:00
|
|
|
let ((wp1,wc1),(wp2,wc2)) = (comm::stream(),comm::stream());
|
2013-02-15 01:30:30 -06:00
|
|
|
do task::spawn || {
|
2012-08-14 12:32:41 -05:00
|
|
|
wp1.recv();
|
|
|
|
do arc2.write_cond |state, cond| {
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*state, 0);
|
2012-08-14 12:32:41 -05:00
|
|
|
*state = 42;
|
|
|
|
cond.signal();
|
|
|
|
}
|
|
|
|
wp1.recv();
|
|
|
|
do arc2.write |state| {
|
|
|
|
// This shouldn't happen until after the downgrade read
|
|
|
|
// section, and all other readers, finish.
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*state, 31337);
|
2012-08-14 12:32:41 -05:00
|
|
|
*state = 42;
|
|
|
|
}
|
|
|
|
wc2.send(());
|
|
|
|
}
|
|
|
|
|
|
|
|
// Downgrader (us)
|
2013-05-01 07:49:48 -05:00
|
|
|
do arc.write_downgrade |mut write_mode| {
|
|
|
|
do write_mode.write_cond |state, cond| {
|
2012-08-14 12:32:41 -05:00
|
|
|
wc1.send(()); // send to another writer who will wake us up
|
|
|
|
while *state == 0 {
|
|
|
|
cond.wait();
|
|
|
|
}
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*state, 42);
|
2012-08-14 12:32:41 -05:00
|
|
|
*state = 31337;
|
|
|
|
// send to other readers
|
2013-05-08 03:49:00 -05:00
|
|
|
for reader_convos.each |x| {
|
2012-09-18 23:41:37 -05:00
|
|
|
match *x {
|
2012-09-28 04:26:20 -05:00
|
|
|
(ref rc, _) => rc.send(()),
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
2013-02-15 01:30:30 -06:00
|
|
|
let read_mode = arc.downgrade(write_mode);
|
2012-08-23 15:51:53 -05:00
|
|
|
do (&read_mode).read |state| {
|
2012-08-14 12:32:41 -05:00
|
|
|
// complete handshake with other readers
|
2013-05-08 03:49:00 -05:00
|
|
|
for reader_convos.each |x| {
|
2012-09-18 23:41:37 -05:00
|
|
|
match *x {
|
2012-09-28 04:26:20 -05:00
|
|
|
(_, ref rp) => rp.recv(),
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
wc1.send(()); // tell writer to try again
|
2013-05-18 21:02:45 -05:00
|
|
|
assert_eq!(*state, 31337);
|
2012-08-14 12:32:41 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
wp2.recv(); // complete handshake with writer
|
|
|
|
}
|
2012-08-10 17:20:03 -05:00
|
|
|
}
|