wasi: Fix sleeping for Duration::MAX

This commit fixes an assert in the WASI-specific implementation of
thread sleep to ensure that sleeping for a very large period of time
blocks instead of panicking. This can come up when testing programs that
sleep "forever", for example.
This commit is contained in:
Alex Crichton 2024-08-29 10:31:17 -07:00
parent 6cf068db56
commit c824c1ada7

View File

@ -136,36 +136,37 @@ pub fn set_name(_name: &CStr) {
}
pub fn sleep(dur: Duration) {
let nanos = dur.as_nanos();
assert!(nanos <= u64::MAX as u128);
let mut nanos = dur.as_nanos();
while nanos > 0 {
const USERDATA: wasi::Userdata = 0x0123_45678;
const USERDATA: wasi::Userdata = 0x0123_45678;
let clock = wasi::SubscriptionClock {
id: wasi::CLOCKID_MONOTONIC,
timeout: u64::try_from(nanos).unwrap_or(u64::MAX),
precision: 0,
flags: 0,
};
nanos -= u128::from(clock.timeout);
let clock = wasi::SubscriptionClock {
id: wasi::CLOCKID_MONOTONIC,
timeout: nanos as u64,
precision: 0,
flags: 0,
};
let in_ = wasi::Subscription {
userdata: USERDATA,
u: wasi::SubscriptionU { tag: 0, u: wasi::SubscriptionUU { clock } },
};
unsafe {
let mut event: wasi::Event = mem::zeroed();
let res = wasi::poll_oneoff(&in_, &mut event, 1);
match (res, event) {
(
Ok(1),
wasi::Event {
userdata: USERDATA,
error: wasi::ERRNO_SUCCESS,
type_: wasi::EVENTTYPE_CLOCK,
..
},
) => {}
_ => panic!("thread::sleep(): unexpected result of poll_oneoff"),
let in_ = wasi::Subscription {
userdata: USERDATA,
u: wasi::SubscriptionU { tag: 0, u: wasi::SubscriptionUU { clock } },
};
unsafe {
let mut event: wasi::Event = mem::zeroed();
let res = wasi::poll_oneoff(&in_, &mut event, 1);
match (res, event) {
(
Ok(1),
wasi::Event {
userdata: USERDATA,
error: wasi::ERRNO_SUCCESS,
type_: wasi::EVENTTYPE_CLOCK,
..
},
) => {}
_ => panic!("thread::sleep(): unexpected result of poll_oneoff"),
}
}
}
}