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Stabilize basic timeout functionality
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This commit renames and stabilizes:

* `Condvar::wait_timeout_ms` (renamed from `wait_timeout`)
* `thread::park_timeout_ms` (renamed from `park_timeout`)
* `thread::sleep_ms` (renamed from `sleep`)

In each case, the timeout is taken as a `u32` number of milliseconds,
rather than a `Duration`.

These functions are likely to be deprecated once a stable form of
`Duration` is available, but there is little cost to having these named
variants around, and it's crucial functionality for 1.0.

[breaking-change]
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aturon committed Apr 1, 2015
1 parent d528aa9 commit 371277f
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Showing 2 changed files with 54 additions and 28 deletions.
50 changes: 31 additions & 19 deletions src/libstd/sync/condvar.rs
Original file line number Diff line number Diff line change
Expand Up @@ -140,33 +140,43 @@ impl Condvar {
/// Wait on this condition variable for a notification, timing out after a
/// specified duration.
///
/// The semantics of this function are equivalent to `wait()` except that
/// the thread will be blocked for roughly no longer than `dur`. This method
/// should not be used for precise timing due to anomalies such as
/// preemption or platform differences that may not cause the maximum amount
/// of time waited to be precisely `dur`.
/// The semantics of this function are equivalent to `wait()`
/// except that the thread will be blocked for roughly no longer
/// than `ms` milliseconds. This method should not be used for
/// precise timing due to anomalies such as preemption or platform
/// differences that may not cause the maximum amount of time
/// waited to be precisely `ms`.
///
/// If the wait timed out, then `false` will be returned. Otherwise if a
/// notification was received then `true` will be returned.
/// The returned boolean is `false` only if the timeout is known
/// to have elapsed.
///
/// Like `wait`, the lock specified will be re-acquired when this function
/// returns, regardless of whether the timeout elapsed or not.
#[unstable(feature = "std_misc")]
pub fn wait_timeout<'a, T>(&self, guard: MutexGuard<'a, T>, dur: Duration)
-> LockResult<(MutexGuard<'a, T>, bool)> {
#[stable(feature = "rust1", since = "1.0.0")]
pub fn wait_timeout_ms<'a, T>(&self, guard: MutexGuard<'a, T>, ms: u32)
-> LockResult<(MutexGuard<'a, T>, bool)> {
unsafe {
let me: &'static Condvar = &*(self as *const _);
me.inner.wait_timeout(guard, dur)
me.inner.wait_timeout_ms(guard, ms)
}
}

/// Deprecated: use `wait_timeout_ms` instead.
#[unstable(feature = "std_misc")]
#[deprecated(since = "1.0.0", reason = "use wait_timeout_ms instead")]
pub fn wait_timeout<'a, T>(&self, guard: MutexGuard<'a, T>, dur: Duration)
-> LockResult<(MutexGuard<'a, T>, bool)> {
self.wait_timeout_ms(guard, dur.num_milliseconds() as u32)
}

/// Wait on this condition variable for a notification, timing out after a
/// specified duration.
///
/// The semantics of this function are equivalent to `wait_timeout` except
/// that the implementation will repeatedly wait while the duration has not
/// passed and the provided function returns `false`.
#[unstable(feature = "std_misc")]
#[unstable(feature = "wait_timeout_with",
reason = "unsure if this API is broadly needed or what form it should take")]
pub fn wait_timeout_with<'a, T, F>(&self,
guard: MutexGuard<'a, T>,
dur: Duration,
Expand Down Expand Up @@ -235,12 +245,12 @@ impl StaticCondvar {
/// See `Condvar::wait_timeout`.
#[unstable(feature = "std_misc",
reason = "may be merged with Condvar in the future")]
pub fn wait_timeout<'a, T>(&'static self, guard: MutexGuard<'a, T>, dur: Duration)
-> LockResult<(MutexGuard<'a, T>, bool)> {
pub fn wait_timeout_ms<'a, T>(&'static self, guard: MutexGuard<'a, T>, ms: u32)
-> LockResult<(MutexGuard<'a, T>, bool)> {
let (poisoned, success) = unsafe {
let lock = mutex::guard_lock(&guard);
self.verify(lock);
let success = self.inner.wait_timeout(lock, dur);
let success = self.inner.wait_timeout(lock, Duration::milliseconds(ms as i64));
(mutex::guard_poison(&guard).get(), success)
};
if poisoned {
Expand Down Expand Up @@ -275,7 +285,8 @@ impl StaticCondvar {
let now = SteadyTime::now();
let consumed = &now - &start;
let guard = guard_result.unwrap_or_else(|e| e.into_inner());
let (new_guard_result, no_timeout) = match self.wait_timeout(guard, dur - consumed) {
let res = self.wait_timeout_ms(guard, (dur - consumed).num_milliseconds() as u32);
let (new_guard_result, no_timeout) = match res {
Ok((new_guard, no_timeout)) => (Ok(new_guard), no_timeout),
Err(err) => {
let (new_guard, no_timeout) = err.into_inner();
Expand Down Expand Up @@ -350,6 +361,7 @@ mod tests {
use sync::atomic::{AtomicUsize, ATOMIC_USIZE_INIT, Ordering};
use thread;
use time::Duration;
use u32;

#[test]
fn smoke() {
Expand Down Expand Up @@ -418,19 +430,19 @@ mod tests {
}

#[test]
fn wait_timeout() {
fn wait_timeout_ms() {
static C: StaticCondvar = CONDVAR_INIT;
static M: StaticMutex = MUTEX_INIT;

let g = M.lock().unwrap();
let (g, _no_timeout) = C.wait_timeout(g, Duration::nanoseconds(1000)).unwrap();
let (g, _no_timeout) = C.wait_timeout_ms(g, 1).unwrap();
// spurious wakeups mean this isn't necessarily true
// assert!(!no_timeout);
let _t = thread::spawn(move || {
let _g = M.lock().unwrap();
C.notify_one();
});
let (g, no_timeout) = C.wait_timeout(g, Duration::days(1)).unwrap();
let (g, no_timeout) = C.wait_timeout_ms(g, u32::MAX).unwrap();
assert!(no_timeout);
drop(g);
unsafe { C.destroy(); M.destroy(); }
Expand Down
32 changes: 23 additions & 9 deletions src/libstd/thread/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -465,9 +465,16 @@ pub fn catch_panic<F, R>(f: F) -> Result<R>
/// specifics or platform-dependent functionality. Note that on unix platforms
/// this function will not return early due to a signal being received or a
/// spurious wakeup.
#[stable(feature = "rust1", since = "1.0.0")]
pub fn sleep_ms(ms: u32) {
imp::sleep(Duration::milliseconds(ms as i64))
}

/// Deprecated: use `sleep_ms` instead.
#[unstable(feature = "thread_sleep",
reason = "recently added, needs an RFC, and `Duration` itself is \
unstable")]
#[deprecated(since = "1.0.0", reason = "use sleep_ms instead")]
pub fn sleep(dur: Duration) {
imp::sleep(dur)
}
Expand Down Expand Up @@ -501,17 +508,24 @@ pub fn park() {
/// amount of time waited to be precisely *duration* long.
///
/// See the module doc for more detail.
#[unstable(feature = "std_misc", reason = "recently introduced, depends on Duration")]
pub fn park_timeout(duration: Duration) {
#[stable(feature = "rust1", since = "1.0.0")]
pub fn park_timeout_ms(ms: u32) {
let thread = current();
let mut guard = thread.inner.lock.lock().unwrap();
if !*guard {
let (g, _) = thread.inner.cvar.wait_timeout(guard, duration).unwrap();
let (g, _) = thread.inner.cvar.wait_timeout_ms(guard, ms).unwrap();
guard = g;
}
*guard = false;
}

/// Deprecated: use `park_timeout_ms`
#[unstable(feature = "std_misc", reason = "recently introduced, depends on Duration")]
#[deprecated(since = "1.0.0", reason = "use park_timeout_ms instead")]
pub fn park_timeout(duration: Duration) {
park_timeout_ms(duration.num_milliseconds() as u32)
}

////////////////////////////////////////////////////////////////////////////////
// Thread
////////////////////////////////////////////////////////////////////////////////
Expand Down Expand Up @@ -716,6 +730,7 @@ mod test {
use thread;
use thunk::Thunk;
use time::Duration;
use u32;

// !!! These tests are dangerous. If something is buggy, they will hang, !!!
// !!! instead of exiting cleanly. This might wedge the buildbots. !!!
Expand Down Expand Up @@ -936,14 +951,14 @@ mod test {
fn test_park_timeout_unpark_before() {
for _ in 0..10 {
thread::current().unpark();
thread::park_timeout(Duration::seconds(10_000_000));
thread::park_timeout_ms(u32::MAX);
}
}

#[test]
fn test_park_timeout_unpark_not_called() {
for _ in 0..10 {
thread::park_timeout(Duration::milliseconds(10));
thread::park_timeout_ms(10);
}
}

Expand All @@ -959,14 +974,13 @@ mod test {
th.unpark();
});

thread::park_timeout(Duration::seconds(10_000_000));
thread::park_timeout_ms(u32::MAX);
}
}

#[test]
fn sleep_smoke() {
thread::sleep(Duration::milliseconds(2));
thread::sleep(Duration::milliseconds(-2));
fn sleep_ms_smoke() {
thread::sleep_ms(2);
}

// NOTE: the corresponding test for stderr is in run-pass/task-stderr, due
Expand Down

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