096a28607f
This change makes the compiler no longer infer whether types (structures
and enumerations) implement the `Copy` trait (and thus are implicitly
copyable). Rather, you must implement `Copy` yourself via `impl Copy for
MyType {}`.
A new warning has been added, `missing_copy_implementations`, to warn
you if a non-generic public type has been added that could have
implemented `Copy` but didn't.
For convenience, you may *temporarily* opt out of this behavior by using
`#![feature(opt_out_copy)]`. Note though that this feature gate will never be
accepted and will be removed by the time that 1.0 is released, so you should
transition your code away from using it.
This breaks code like:
#[deriving(Show)]
struct Point2D {
x: int,
y: int,
}
fn main() {
let mypoint = Point2D {
x: 1,
y: 1,
};
let otherpoint = mypoint;
println!("{}{}", mypoint, otherpoint);
}
Change this code to:
#[deriving(Show)]
struct Point2D {
x: int,
y: int,
}
impl Copy for Point2D {}
fn main() {
let mypoint = Point2D {
x: 1,
y: 1,
};
let otherpoint = mypoint;
println!("{}{}", mypoint, otherpoint);
}
This is the backwards-incompatible part of #13231.
Part of RFC #3.
[breaking-change]
728 lines
23 KiB
Rust
728 lines
23 KiB
Rust
// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
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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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//! A native mutex and condition variable type.
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//!
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//! This module contains bindings to the platform's native mutex/condition
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//! variable primitives. It provides two types: `StaticNativeMutex`, which can
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//! be statically initialized via the `NATIVE_MUTEX_INIT` value, and a simple
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//! wrapper `NativeMutex` that has a destructor to clean up after itself. These
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//! objects serve as both mutexes and condition variables simultaneously.
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//!
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//! The static lock is lazily initialized, but it can only be unsafely
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//! destroyed. A statically initialized lock doesn't necessarily have a time at
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//! which it can get deallocated. For this reason, there is no `Drop`
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//! implementation of the static mutex, but rather the `destroy()` method must
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//! be invoked manually if destruction of the mutex is desired.
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//!
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//! The non-static `NativeMutex` type does have a destructor, but cannot be
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//! statically initialized.
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//!
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//! It is not recommended to use this type for idiomatic rust use. These types
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//! are appropriate where no other options are available, but other rust
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//! concurrency primitives should be used before them: the `sync` crate defines
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//! `StaticMutex` and `Mutex` types.
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//!
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//! # Example
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//!
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//! ```rust
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//! use rustrt::mutex::{NativeMutex, StaticNativeMutex, NATIVE_MUTEX_INIT};
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//!
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//! // Use a statically initialized mutex
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//! static LOCK: StaticNativeMutex = NATIVE_MUTEX_INIT;
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//!
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//! unsafe {
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//! let _guard = LOCK.lock();
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//! } // automatically unlocked here
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//!
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//! // Use a normally initialized mutex
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//! unsafe {
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//! let mut lock = NativeMutex::new();
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//!
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//! {
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//! let _guard = lock.lock();
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//! } // unlocked here
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//!
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//! // sometimes the RAII guard isn't appropriate
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//! lock.lock_noguard();
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//! lock.unlock_noguard();
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//! } // `lock` is deallocated here
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//! ```
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#![allow(non_camel_case_types)]
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use core::prelude::*;
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/// A native mutex suitable for storing in statics (that is, it has
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/// the `destroy` method rather than a destructor).
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///
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/// Prefer the `NativeMutex` type where possible, since that does not
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/// require manual deallocation.
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pub struct StaticNativeMutex {
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inner: imp::Mutex,
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}
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/// A native mutex with a destructor for clean-up.
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///
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/// See `StaticNativeMutex` for a version that is suitable for storing in
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/// statics.
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pub struct NativeMutex {
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inner: StaticNativeMutex
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}
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/// Automatically unlocks the mutex that it was created from on
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/// destruction.
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///
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/// Using this makes lock-based code resilient to unwinding/task
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/// panic, because the lock will be automatically unlocked even
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/// then.
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#[must_use]
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pub struct LockGuard<'a> {
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lock: &'a StaticNativeMutex
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}
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pub const NATIVE_MUTEX_INIT: StaticNativeMutex = StaticNativeMutex {
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inner: imp::MUTEX_INIT,
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};
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impl StaticNativeMutex {
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/// Creates a new mutex.
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///
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/// Note that a mutex created in this way needs to be explicit
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/// freed with a call to `destroy` or it will leak.
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/// Also it is important to avoid locking until mutex has stopped moving
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pub unsafe fn new() -> StaticNativeMutex {
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StaticNativeMutex { inner: imp::Mutex::new() }
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}
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/// Acquires this lock. This assumes that the current thread does not
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/// already hold the lock.
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///
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/// # Example
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///
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/// ```rust
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/// use rustrt::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
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/// static LOCK: StaticNativeMutex = NATIVE_MUTEX_INIT;
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/// unsafe {
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/// let _guard = LOCK.lock();
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/// // critical section...
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/// } // automatically unlocked in `_guard`'s destructor
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/// ```
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///
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/// # Unsafety
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///
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/// This method is unsafe because it will not function correctly if this
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/// mutex has been *moved* since it was last used. The mutex can move an
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/// arbitrary number of times before its first usage, but once a mutex has
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/// been used once it is no longer allowed to move (or otherwise it invokes
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/// undefined behavior).
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///
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/// Additionally, this type does not take into account any form of
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/// scheduling model. This will unconditionally block the *os thread* which
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/// is not always desired.
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pub unsafe fn lock<'a>(&'a self) -> LockGuard<'a> {
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self.inner.lock();
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LockGuard { lock: self }
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}
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/// Attempts to acquire the lock. The value returned is `Some` if
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/// the attempt succeeded.
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///
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/// # Unsafety
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///
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/// This method is unsafe for the same reasons as `lock`.
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pub unsafe fn trylock<'a>(&'a self) -> Option<LockGuard<'a>> {
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if self.inner.trylock() {
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Some(LockGuard { lock: self })
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} else {
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None
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}
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}
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/// Acquire the lock without creating a `LockGuard`.
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///
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/// These needs to be paired with a call to `.unlock_noguard`. Prefer using
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/// `.lock`.
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///
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/// # Unsafety
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///
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/// This method is unsafe for the same reasons as `lock`. Additionally, this
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/// does not guarantee that the mutex will ever be unlocked, and it is
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/// undefined to drop an already-locked mutex.
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pub unsafe fn lock_noguard(&self) { self.inner.lock() }
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/// Attempts to acquire the lock without creating a
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/// `LockGuard`. The value returned is whether the lock was
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/// acquired or not.
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///
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/// If `true` is returned, this needs to be paired with a call to
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/// `.unlock_noguard`. Prefer using `.trylock`.
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///
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/// # Unsafety
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///
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/// This method is unsafe for the same reasons as `lock_noguard`.
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pub unsafe fn trylock_noguard(&self) -> bool {
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self.inner.trylock()
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}
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/// Unlocks the lock. This assumes that the current thread already holds the
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/// lock.
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///
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/// # Unsafety
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///
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/// This method is unsafe for the same reasons as `lock`. Additionally, it
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/// is not guaranteed that this is unlocking a previously locked mutex. It
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/// is undefined to unlock an unlocked mutex.
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pub unsafe fn unlock_noguard(&self) { self.inner.unlock() }
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/// Block on the internal condition variable.
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///
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/// This function assumes that the lock is already held. Prefer
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/// using `LockGuard.wait` since that guarantees that the lock is
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/// held.
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///
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/// # Unsafety
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///
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/// This method is unsafe for the same reasons as `lock`. Additionally, this
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/// is unsafe because the mutex may not be currently locked.
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pub unsafe fn wait_noguard(&self) { self.inner.wait() }
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/// Signals a thread in `wait` to wake up
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///
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/// # Unsafety
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///
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/// This method is unsafe for the same reasons as `lock`. Additionally, this
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/// is unsafe because the mutex may not be currently locked.
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pub unsafe fn signal_noguard(&self) { self.inner.signal() }
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/// This function is especially unsafe because there are no guarantees made
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/// that no other thread is currently holding the lock or waiting on the
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/// condition variable contained inside.
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pub unsafe fn destroy(&self) { self.inner.destroy() }
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}
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impl NativeMutex {
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/// Creates a new mutex.
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///
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/// The user must be careful to ensure the mutex is not locked when its is
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/// being destroyed.
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/// Also it is important to avoid locking until mutex has stopped moving
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pub unsafe fn new() -> NativeMutex {
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NativeMutex { inner: StaticNativeMutex::new() }
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}
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/// Acquires this lock. This assumes that the current thread does not
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/// already hold the lock.
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///
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/// # Example
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///
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/// ```rust
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/// use rustrt::mutex::NativeMutex;
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/// unsafe {
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/// let mut lock = NativeMutex::new();
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///
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/// {
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/// let _guard = lock.lock();
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/// // critical section...
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/// } // automatically unlocked in `_guard`'s destructor
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/// }
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/// ```
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///
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/// # Unsafety
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///
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/// This method is unsafe due to the same reasons as
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/// `StaticNativeMutex::lock`.
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pub unsafe fn lock<'a>(&'a self) -> LockGuard<'a> {
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self.inner.lock()
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}
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/// Attempts to acquire the lock. The value returned is `Some` if
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/// the attempt succeeded.
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///
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/// # Unsafety
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///
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/// This method is unsafe due to the same reasons as
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/// `StaticNativeMutex::trylock`.
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pub unsafe fn trylock<'a>(&'a self) -> Option<LockGuard<'a>> {
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self.inner.trylock()
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}
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/// Acquire the lock without creating a `LockGuard`.
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///
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/// These needs to be paired with a call to `.unlock_noguard`. Prefer using
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/// `.lock`.
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///
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/// # Unsafety
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///
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/// This method is unsafe due to the same reasons as
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/// `StaticNativeMutex::lock_noguard`.
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pub unsafe fn lock_noguard(&self) { self.inner.lock_noguard() }
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/// Attempts to acquire the lock without creating a
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/// `LockGuard`. The value returned is whether the lock was
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/// acquired or not.
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///
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/// If `true` is returned, this needs to be paired with a call to
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/// `.unlock_noguard`. Prefer using `.trylock`.
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///
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/// # Unsafety
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///
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/// This method is unsafe due to the same reasons as
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/// `StaticNativeMutex::trylock_noguard`.
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pub unsafe fn trylock_noguard(&self) -> bool {
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self.inner.trylock_noguard()
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}
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/// Unlocks the lock. This assumes that the current thread already holds the
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/// lock.
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///
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/// # Unsafety
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///
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/// This method is unsafe due to the same reasons as
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/// `StaticNativeMutex::unlock_noguard`.
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pub unsafe fn unlock_noguard(&self) { self.inner.unlock_noguard() }
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/// Block on the internal condition variable.
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///
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/// This function assumes that the lock is already held. Prefer
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/// using `LockGuard.wait` since that guarantees that the lock is
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/// held.
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///
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/// # Unsafety
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///
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/// This method is unsafe due to the same reasons as
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/// `StaticNativeMutex::wait_noguard`.
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pub unsafe fn wait_noguard(&self) { self.inner.wait_noguard() }
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/// Signals a thread in `wait` to wake up
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///
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/// # Unsafety
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///
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/// This method is unsafe due to the same reasons as
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/// `StaticNativeMutex::signal_noguard`.
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pub unsafe fn signal_noguard(&self) { self.inner.signal_noguard() }
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}
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impl Drop for NativeMutex {
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fn drop(&mut self) {
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unsafe {self.inner.destroy()}
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}
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}
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impl<'a> LockGuard<'a> {
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/// Block on the internal condition variable.
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pub unsafe fn wait(&self) {
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self.lock.wait_noguard()
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}
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/// Signals a thread in `wait` to wake up.
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pub unsafe fn signal(&self) {
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self.lock.signal_noguard()
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}
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}
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#[unsafe_destructor]
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impl<'a> Drop for LockGuard<'a> {
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fn drop(&mut self) {
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unsafe {self.lock.unlock_noguard()}
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}
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}
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#[cfg(unix)]
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mod imp {
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use libc;
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use self::os::{PTHREAD_MUTEX_INITIALIZER, PTHREAD_COND_INITIALIZER,
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pthread_mutex_t, pthread_cond_t};
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use core::cell::UnsafeCell;
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type pthread_mutexattr_t = libc::c_void;
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type pthread_condattr_t = libc::c_void;
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#[cfg(any(target_os = "freebsd", target_os = "dragonfly"))]
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mod os {
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use libc;
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pub type pthread_mutex_t = *mut libc::c_void;
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pub type pthread_cond_t = *mut libc::c_void;
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pub const PTHREAD_MUTEX_INITIALIZER: pthread_mutex_t =
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0 as pthread_mutex_t;
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pub const PTHREAD_COND_INITIALIZER: pthread_cond_t =
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0 as pthread_cond_t;
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}
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#[cfg(any(target_os = "macos", target_os = "ios"))]
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mod os {
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use core::kinds::Copy;
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use libc;
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#[cfg(target_arch = "x86_64")]
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const __PTHREAD_MUTEX_SIZE__: uint = 56;
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#[cfg(target_arch = "x86_64")]
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const __PTHREAD_COND_SIZE__: uint = 40;
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#[cfg(target_arch = "x86")]
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const __PTHREAD_MUTEX_SIZE__: uint = 40;
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#[cfg(target_arch = "x86")]
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const __PTHREAD_COND_SIZE__: uint = 24;
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#[cfg(target_arch = "arm")]
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const __PTHREAD_MUTEX_SIZE__: uint = 40;
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#[cfg(target_arch = "arm")]
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const __PTHREAD_COND_SIZE__: uint = 24;
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const _PTHREAD_MUTEX_SIG_INIT: libc::c_long = 0x32AAABA7;
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const _PTHREAD_COND_SIG_INIT: libc::c_long = 0x3CB0B1BB;
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#[repr(C)]
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pub struct pthread_mutex_t {
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__sig: libc::c_long,
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__opaque: [u8, ..__PTHREAD_MUTEX_SIZE__],
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}
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impl Copy for pthread_mutex_t {}
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#[repr(C)]
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pub struct pthread_cond_t {
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__sig: libc::c_long,
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__opaque: [u8, ..__PTHREAD_COND_SIZE__],
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}
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impl Copy for pthread_cond_t {}
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pub const PTHREAD_MUTEX_INITIALIZER: pthread_mutex_t = pthread_mutex_t {
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__sig: _PTHREAD_MUTEX_SIG_INIT,
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__opaque: [0, ..__PTHREAD_MUTEX_SIZE__],
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};
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pub const PTHREAD_COND_INITIALIZER: pthread_cond_t = pthread_cond_t {
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__sig: _PTHREAD_COND_SIG_INIT,
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__opaque: [0, ..__PTHREAD_COND_SIZE__],
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};
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}
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#[cfg(target_os = "linux")]
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mod os {
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use core::kinds::Copy;
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use libc;
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// minus 8 because we have an 'align' field
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#[cfg(target_arch = "x86_64")]
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const __SIZEOF_PTHREAD_MUTEX_T: uint = 40 - 8;
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#[cfg(target_arch = "x86")]
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const __SIZEOF_PTHREAD_MUTEX_T: uint = 24 - 8;
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#[cfg(target_arch = "arm")]
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|
const __SIZEOF_PTHREAD_MUTEX_T: uint = 24 - 8;
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|
#[cfg(target_arch = "mips")]
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|
const __SIZEOF_PTHREAD_MUTEX_T: uint = 24 - 8;
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#[cfg(target_arch = "mipsel")]
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|
const __SIZEOF_PTHREAD_MUTEX_T: uint = 24 - 8;
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#[cfg(target_arch = "x86_64")]
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const __SIZEOF_PTHREAD_COND_T: uint = 48 - 8;
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#[cfg(target_arch = "x86")]
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|
const __SIZEOF_PTHREAD_COND_T: uint = 48 - 8;
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|
#[cfg(target_arch = "arm")]
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|
const __SIZEOF_PTHREAD_COND_T: uint = 48 - 8;
|
|
#[cfg(target_arch = "mips")]
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|
const __SIZEOF_PTHREAD_COND_T: uint = 48 - 8;
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|
#[cfg(target_arch = "mipsel")]
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|
const __SIZEOF_PTHREAD_COND_T: uint = 48 - 8;
|
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#[repr(C)]
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|
pub struct pthread_mutex_t {
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__align: libc::c_longlong,
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size: [u8, ..__SIZEOF_PTHREAD_MUTEX_T],
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}
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|
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impl Copy for pthread_mutex_t {}
|
|
|
|
#[repr(C)]
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|
pub struct pthread_cond_t {
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|
__align: libc::c_longlong,
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|
size: [u8, ..__SIZEOF_PTHREAD_COND_T],
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}
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|
|
|
impl Copy for pthread_cond_t {}
|
|
|
|
pub const PTHREAD_MUTEX_INITIALIZER: pthread_mutex_t = pthread_mutex_t {
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__align: 0,
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size: [0, ..__SIZEOF_PTHREAD_MUTEX_T],
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|
};
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|
pub const PTHREAD_COND_INITIALIZER: pthread_cond_t = pthread_cond_t {
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|
__align: 0,
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|
size: [0, ..__SIZEOF_PTHREAD_COND_T],
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|
};
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|
}
|
|
#[cfg(target_os = "android")]
|
|
mod os {
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|
use libc;
|
|
|
|
#[repr(C)]
|
|
pub struct pthread_mutex_t { value: libc::c_int }
|
|
#[repr(C)]
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|
pub struct pthread_cond_t { value: libc::c_int }
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|
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pub const PTHREAD_MUTEX_INITIALIZER: pthread_mutex_t = pthread_mutex_t {
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value: 0,
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};
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pub const PTHREAD_COND_INITIALIZER: pthread_cond_t = pthread_cond_t {
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value: 0,
|
|
};
|
|
}
|
|
|
|
pub struct Mutex {
|
|
lock: UnsafeCell<pthread_mutex_t>,
|
|
cond: UnsafeCell<pthread_cond_t>,
|
|
}
|
|
|
|
pub const MUTEX_INIT: Mutex = Mutex {
|
|
lock: UnsafeCell { value: PTHREAD_MUTEX_INITIALIZER },
|
|
cond: UnsafeCell { value: PTHREAD_COND_INITIALIZER },
|
|
};
|
|
|
|
impl Mutex {
|
|
pub unsafe fn new() -> Mutex {
|
|
// As mutex might be moved and address is changing it
|
|
// is better to avoid initialization of potentially
|
|
// opaque OS data before it landed
|
|
let m = Mutex {
|
|
lock: UnsafeCell::new(PTHREAD_MUTEX_INITIALIZER),
|
|
cond: UnsafeCell::new(PTHREAD_COND_INITIALIZER),
|
|
};
|
|
|
|
return m;
|
|
}
|
|
|
|
pub unsafe fn lock(&self) { pthread_mutex_lock(self.lock.get()); }
|
|
pub unsafe fn unlock(&self) { pthread_mutex_unlock(self.lock.get()); }
|
|
pub unsafe fn signal(&self) { pthread_cond_signal(self.cond.get()); }
|
|
pub unsafe fn wait(&self) {
|
|
pthread_cond_wait(self.cond.get(), self.lock.get());
|
|
}
|
|
pub unsafe fn trylock(&self) -> bool {
|
|
pthread_mutex_trylock(self.lock.get()) == 0
|
|
}
|
|
pub unsafe fn destroy(&self) {
|
|
pthread_mutex_destroy(self.lock.get());
|
|
pthread_cond_destroy(self.cond.get());
|
|
}
|
|
}
|
|
|
|
extern {
|
|
fn pthread_mutex_destroy(lock: *mut pthread_mutex_t) -> libc::c_int;
|
|
fn pthread_cond_destroy(cond: *mut pthread_cond_t) -> libc::c_int;
|
|
fn pthread_mutex_lock(lock: *mut pthread_mutex_t) -> libc::c_int;
|
|
fn pthread_mutex_trylock(lock: *mut pthread_mutex_t) -> libc::c_int;
|
|
fn pthread_mutex_unlock(lock: *mut pthread_mutex_t) -> libc::c_int;
|
|
|
|
fn pthread_cond_wait(cond: *mut pthread_cond_t,
|
|
lock: *mut pthread_mutex_t) -> libc::c_int;
|
|
fn pthread_cond_signal(cond: *mut pthread_cond_t) -> libc::c_int;
|
|
}
|
|
}
|
|
|
|
#[cfg(windows)]
|
|
mod imp {
|
|
use alloc::heap;
|
|
use core::atomic;
|
|
use core::ptr;
|
|
use core::ptr::RawPtr;
|
|
use libc::{HANDLE, BOOL, LPSECURITY_ATTRIBUTES, c_void, DWORD, LPCSTR};
|
|
use libc;
|
|
|
|
type LPCRITICAL_SECTION = *mut c_void;
|
|
const SPIN_COUNT: DWORD = 4000;
|
|
#[cfg(target_arch = "x86")]
|
|
const CRIT_SECTION_SIZE: uint = 24;
|
|
#[cfg(target_arch = "x86_64")]
|
|
const CRIT_SECTION_SIZE: uint = 40;
|
|
|
|
pub struct Mutex {
|
|
// pointers for the lock/cond handles, atomically updated
|
|
lock: atomic::AtomicUint,
|
|
cond: atomic::AtomicUint,
|
|
}
|
|
|
|
pub const MUTEX_INIT: Mutex = Mutex {
|
|
lock: atomic::INIT_ATOMIC_UINT,
|
|
cond: atomic::INIT_ATOMIC_UINT,
|
|
};
|
|
|
|
impl Mutex {
|
|
pub unsafe fn new() -> Mutex {
|
|
Mutex {
|
|
lock: atomic::AtomicUint::new(init_lock()),
|
|
cond: atomic::AtomicUint::new(init_cond()),
|
|
}
|
|
}
|
|
pub unsafe fn lock(&self) {
|
|
EnterCriticalSection(self.getlock() as LPCRITICAL_SECTION)
|
|
}
|
|
pub unsafe fn trylock(&self) -> bool {
|
|
TryEnterCriticalSection(self.getlock() as LPCRITICAL_SECTION) != 0
|
|
}
|
|
pub unsafe fn unlock(&self) {
|
|
LeaveCriticalSection(self.getlock() as LPCRITICAL_SECTION)
|
|
}
|
|
|
|
pub unsafe fn wait(&self) {
|
|
self.unlock();
|
|
WaitForSingleObject(self.getcond() as HANDLE, libc::INFINITE);
|
|
self.lock();
|
|
}
|
|
|
|
pub unsafe fn signal(&self) {
|
|
assert!(SetEvent(self.getcond() as HANDLE) != 0);
|
|
}
|
|
|
|
/// This function is especially unsafe because there are no guarantees made
|
|
/// that no other thread is currently holding the lock or waiting on the
|
|
/// condition variable contained inside.
|
|
pub unsafe fn destroy(&self) {
|
|
let lock = self.lock.swap(0, atomic::SeqCst);
|
|
let cond = self.cond.swap(0, atomic::SeqCst);
|
|
if lock != 0 { free_lock(lock) }
|
|
if cond != 0 { free_cond(cond) }
|
|
}
|
|
|
|
unsafe fn getlock(&self) -> *mut c_void {
|
|
match self.lock.load(atomic::SeqCst) {
|
|
0 => {}
|
|
n => return n as *mut c_void
|
|
}
|
|
let lock = init_lock();
|
|
match self.lock.compare_and_swap(0, lock, atomic::SeqCst) {
|
|
0 => return lock as *mut c_void,
|
|
_ => {}
|
|
}
|
|
free_lock(lock);
|
|
return self.lock.load(atomic::SeqCst) as *mut c_void;
|
|
}
|
|
|
|
unsafe fn getcond(&self) -> *mut c_void {
|
|
match self.cond.load(atomic::SeqCst) {
|
|
0 => {}
|
|
n => return n as *mut c_void
|
|
}
|
|
let cond = init_cond();
|
|
match self.cond.compare_and_swap(0, cond, atomic::SeqCst) {
|
|
0 => return cond as *mut c_void,
|
|
_ => {}
|
|
}
|
|
free_cond(cond);
|
|
return self.cond.load(atomic::SeqCst) as *mut c_void;
|
|
}
|
|
}
|
|
|
|
pub unsafe fn init_lock() -> uint {
|
|
let block = heap::allocate(CRIT_SECTION_SIZE, 8) as *mut c_void;
|
|
if block.is_null() { ::alloc::oom() }
|
|
InitializeCriticalSectionAndSpinCount(block, SPIN_COUNT);
|
|
return block as uint;
|
|
}
|
|
|
|
pub unsafe fn init_cond() -> uint {
|
|
return CreateEventA(ptr::null_mut(), libc::FALSE, libc::FALSE,
|
|
ptr::null()) as uint;
|
|
}
|
|
|
|
pub unsafe fn free_lock(h: uint) {
|
|
DeleteCriticalSection(h as LPCRITICAL_SECTION);
|
|
heap::deallocate(h as *mut u8, CRIT_SECTION_SIZE, 8);
|
|
}
|
|
|
|
pub unsafe fn free_cond(h: uint) {
|
|
let block = h as HANDLE;
|
|
libc::CloseHandle(block);
|
|
}
|
|
|
|
#[allow(non_snake_case)]
|
|
extern "system" {
|
|
fn CreateEventA(lpSecurityAttributes: LPSECURITY_ATTRIBUTES,
|
|
bManualReset: BOOL,
|
|
bInitialState: BOOL,
|
|
lpName: LPCSTR) -> HANDLE;
|
|
fn InitializeCriticalSectionAndSpinCount(
|
|
lpCriticalSection: LPCRITICAL_SECTION,
|
|
dwSpinCount: DWORD) -> BOOL;
|
|
fn DeleteCriticalSection(lpCriticalSection: LPCRITICAL_SECTION);
|
|
fn EnterCriticalSection(lpCriticalSection: LPCRITICAL_SECTION);
|
|
fn LeaveCriticalSection(lpCriticalSection: LPCRITICAL_SECTION);
|
|
fn TryEnterCriticalSection(lpCriticalSection: LPCRITICAL_SECTION) -> BOOL;
|
|
fn SetEvent(hEvent: HANDLE) -> BOOL;
|
|
fn WaitForSingleObject(hHandle: HANDLE, dwMilliseconds: DWORD) -> DWORD;
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod test {
|
|
use std::prelude::*;
|
|
|
|
use std::mem::drop;
|
|
use super::{StaticNativeMutex, NATIVE_MUTEX_INIT};
|
|
use thread::Thread;
|
|
|
|
#[test]
|
|
fn smoke_lock() {
|
|
static LK: StaticNativeMutex = NATIVE_MUTEX_INIT;
|
|
unsafe {
|
|
let _guard = LK.lock();
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn smoke_cond() {
|
|
static LK: StaticNativeMutex = NATIVE_MUTEX_INIT;
|
|
unsafe {
|
|
let guard = LK.lock();
|
|
let t = Thread::start(proc() {
|
|
let guard = LK.lock();
|
|
guard.signal();
|
|
});
|
|
guard.wait();
|
|
drop(guard);
|
|
|
|
t.join();
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn smoke_lock_noguard() {
|
|
static LK: StaticNativeMutex = NATIVE_MUTEX_INIT;
|
|
unsafe {
|
|
LK.lock_noguard();
|
|
LK.unlock_noguard();
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn smoke_cond_noguard() {
|
|
static LK: StaticNativeMutex = NATIVE_MUTEX_INIT;
|
|
unsafe {
|
|
LK.lock_noguard();
|
|
let t = Thread::start(proc() {
|
|
LK.lock_noguard();
|
|
LK.signal_noguard();
|
|
LK.unlock_noguard();
|
|
});
|
|
LK.wait_noguard();
|
|
LK.unlock_noguard();
|
|
|
|
t.join();
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn destroy_immediately() {
|
|
unsafe {
|
|
let m = StaticNativeMutex::new();
|
|
m.destroy();
|
|
}
|
|
}
|
|
}
|