Struct wasi_common::sched::Poll
source · pub struct Poll<'a> { /* private fields */ }Implementations§
source§impl<'a> Poll<'a>
impl<'a> Poll<'a>
sourcepub fn new() -> Self
pub fn new() -> Self
Examples found in repository?
src/snapshots/preview_0.rs (line 882)
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async fn poll_oneoff<'a>(
&mut self,
subs: &GuestPtr<'a, types::Subscription>,
events: &GuestPtr<'a, types::Event>,
nsubscriptions: types::Size,
) -> Result<types::Size, Error> {
if nsubscriptions == 0 {
return Err(Error::invalid_argument().context("nsubscriptions must be nonzero"));
}
// Special-case a `poll_oneoff` which is just sleeping on a single
// relative timer event, such as what WASI libc uses to implement sleep
// functions. This supports all clock IDs, because POSIX says that
// `clock_settime` doesn't effect relative sleeps.
if nsubscriptions == 1 {
let sub = subs.read()?;
if let types::SubscriptionU::Clock(clocksub) = sub.u {
if !clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.sched
.sleep(Duration::from_nanos(clocksub.timeout))
.await?;
events.write(types::Event {
userdata: sub.userdata,
error: types::Errno::Success,
type_: types::Eventtype::Clock,
fd_readwrite: fd_readwrite_empty(),
})?;
return Ok(1);
}
}
}
let table = &mut self.table;
let mut sub_fds: HashSet<types::Fd> = HashSet::new();
// We need these refmuts to outlive Poll, which will hold the &mut dyn WasiFile inside
let mut reads: Vec<(u32, Userdata)> = Vec::new();
let mut writes: Vec<(u32, Userdata)> = Vec::new();
let mut poll = Poll::new();
let subs = subs.as_array(nsubscriptions);
for sub_elem in subs.iter() {
let sub_ptr = sub_elem?;
let sub = sub_ptr.read()?;
match sub.u {
types::SubscriptionU::Clock(clocksub) => match clocksub.id {
types::Clockid::Monotonic => {
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.clocks
.creation_time
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
_ => Err(Error::invalid_argument()
.context("timer subscriptions only support monotonic timer"))?,
},
types::SubscriptionU::FdRead(readsub) => {
let fd = readsub.file_descriptor;
if sub_fds.contains(&fd) {
return Err(Error::invalid_argument()
.context("Fd can be subscribed to at most once per poll"));
} else {
sub_fds.insert(fd);
}
table
.get_file_mut(u32::from(fd))?
.get_cap_mut(FileCaps::POLL_READWRITE)?;
reads.push((u32::from(fd), sub.userdata.into()));
}
types::SubscriptionU::FdWrite(writesub) => {
let fd = writesub.file_descriptor;
if sub_fds.contains(&fd) {
return Err(Error::invalid_argument()
.context("Fd can be subscribed to at most once per poll"));
} else {
sub_fds.insert(fd);
}
table
.get_file_mut(u32::from(fd))?
.get_cap_mut(FileCaps::POLL_READWRITE)?;
writes.push((u32::from(fd), sub.userdata.into()));
}
}
}
self.sched.poll_oneoff(&mut poll).await?;
let results = poll.results();
let num_results = results.len();
assert!(
num_results <= nsubscriptions as usize,
"results exceeds subscriptions"
);
let events = events.as_array(
num_results
.try_into()
.expect("not greater than nsubscriptions"),
);
for ((result, userdata), event_elem) in results.into_iter().zip(events.iter()) {
let event_ptr = event_elem?;
let userdata: types::Userdata = userdata.into();
event_ptr.write(match result {
SubscriptionResult::Read(r) => {
let type_ = types::Eventtype::FdRead;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: types::Errno::from(e.downcast().map_err(Error::trap)?),
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::Write(r) => {
let type_ = types::Eventtype::FdWrite;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: types::Errno::from(e.downcast().map_err(Error::trap)?),
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::MonotonicClock(r) => {
let type_ = types::Eventtype::Clock;
types::Event {
userdata,
error: match r {
Ok(()) => types::Errno::Success,
Err(e) => types::Errno::from(e.downcast().map_err(Error::trap)?),
},
type_,
fd_readwrite: fd_readwrite_empty(),
}
}
})?;
}
Ok(num_results.try_into().expect("results fit into memory"))
}More examples
src/snapshots/preview_1.rs (line 848)
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async fn poll_oneoff<'a>(
&mut self,
subs: &GuestPtr<'a, types::Subscription>,
events: &GuestPtr<'a, types::Event>,
nsubscriptions: types::Size,
) -> Result<types::Size, Error> {
if nsubscriptions == 0 {
return Err(Error::invalid_argument().context("nsubscriptions must be nonzero"));
}
// Special-case a `poll_oneoff` which is just sleeping on a single
// relative timer event, such as what WASI libc uses to implement sleep
// functions. This supports all clock IDs, because POSIX says that
// `clock_settime` doesn't effect relative sleeps.
if nsubscriptions == 1 {
let sub = subs.read()?;
if let types::SubscriptionU::Clock(clocksub) = sub.u {
if !clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.sched
.sleep(Duration::from_nanos(clocksub.timeout))
.await?;
events.write(types::Event {
userdata: sub.userdata,
error: types::Errno::Success,
type_: types::Eventtype::Clock,
fd_readwrite: fd_readwrite_empty(),
})?;
return Ok(1);
}
}
}
let table = &mut self.table;
// We need these refmuts to outlive Poll, which will hold the &mut dyn WasiFile inside
let mut read_refs: Vec<(&dyn WasiFile, Userdata)> = Vec::new();
let mut write_refs: Vec<(&dyn WasiFile, Userdata)> = Vec::new();
let mut poll = Poll::new();
let subs = subs.as_array(nsubscriptions);
for sub_elem in subs.iter() {
let sub_ptr = sub_elem?;
let sub = sub_ptr.read()?;
match sub.u {
types::SubscriptionU::Clock(clocksub) => match clocksub.id {
types::Clockid::Monotonic => {
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.clocks
.creation_time
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
types::Clockid::Realtime => {
// POSIX specifies that functions like `nanosleep` and others use the
// `REALTIME` clock. But it also says that `clock_settime` has no effect
// on threads waiting in these functions. MONOTONIC should always have
// resolution at least as good as REALTIME, so we can translate a
// non-absolute `REALTIME` request into a `MONOTONIC` request.
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
return Err(Error::not_supported());
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
_ => Err(Error::invalid_argument()
.context("timer subscriptions only support monotonic timer"))?,
},
types::SubscriptionU::FdRead(readsub) => {
let fd = readsub.file_descriptor;
let file_ref = table
.get_file(u32::from(fd))?
.get_cap(FileCaps::POLL_READWRITE)?;
read_refs.push((file_ref, sub.userdata.into()));
}
types::SubscriptionU::FdWrite(writesub) => {
let fd = writesub.file_descriptor;
let file_ref = table
.get_file(u32::from(fd))?
.get_cap(FileCaps::POLL_READWRITE)?;
write_refs.push((file_ref, sub.userdata.into()));
}
}
}
for (f, ud) in read_refs.iter_mut() {
poll.subscribe_read(*f, *ud);
}
for (f, ud) in write_refs.iter_mut() {
poll.subscribe_write(*f, *ud);
}
self.sched.poll_oneoff(&mut poll).await?;
let results = poll.results();
let num_results = results.len();
assert!(
num_results <= nsubscriptions as usize,
"results exceeds subscriptions"
);
let events = events.as_array(
num_results
.try_into()
.expect("not greater than nsubscriptions"),
);
for ((result, userdata), event_elem) in results.into_iter().zip(events.iter()) {
let event_ptr = event_elem?;
let userdata: types::Userdata = userdata.into();
event_ptr.write(match result {
SubscriptionResult::Read(r) => {
let type_ = types::Eventtype::FdRead;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: e.downcast().map_err(Error::trap)?,
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::Write(r) => {
let type_ = types::Eventtype::FdWrite;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: e.downcast().map_err(Error::trap)?,
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::MonotonicClock(r) => {
let type_ = types::Eventtype::Clock;
types::Event {
userdata,
error: match r {
Ok(()) => types::Errno::Success,
Err(e) => e.downcast().map_err(Error::trap)?,
},
type_,
fd_readwrite: fd_readwrite_empty(),
}
}
})?;
}
Ok(num_results.try_into().expect("results fit into memory"))
}sourcepub fn subscribe_monotonic_clock(
&mut self,
clock: &'a dyn WasiMonotonicClock,
deadline: Instant,
precision: Duration,
ud: Userdata
)
pub fn subscribe_monotonic_clock(
&mut self,
clock: &'a dyn WasiMonotonicClock,
deadline: Instant,
precision: Duration,
ud: Userdata
)
Examples found in repository?
src/snapshots/preview_0.rs (lines 908-913)
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async fn poll_oneoff<'a>(
&mut self,
subs: &GuestPtr<'a, types::Subscription>,
events: &GuestPtr<'a, types::Event>,
nsubscriptions: types::Size,
) -> Result<types::Size, Error> {
if nsubscriptions == 0 {
return Err(Error::invalid_argument().context("nsubscriptions must be nonzero"));
}
// Special-case a `poll_oneoff` which is just sleeping on a single
// relative timer event, such as what WASI libc uses to implement sleep
// functions. This supports all clock IDs, because POSIX says that
// `clock_settime` doesn't effect relative sleeps.
if nsubscriptions == 1 {
let sub = subs.read()?;
if let types::SubscriptionU::Clock(clocksub) = sub.u {
if !clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.sched
.sleep(Duration::from_nanos(clocksub.timeout))
.await?;
events.write(types::Event {
userdata: sub.userdata,
error: types::Errno::Success,
type_: types::Eventtype::Clock,
fd_readwrite: fd_readwrite_empty(),
})?;
return Ok(1);
}
}
}
let table = &mut self.table;
let mut sub_fds: HashSet<types::Fd> = HashSet::new();
// We need these refmuts to outlive Poll, which will hold the &mut dyn WasiFile inside
let mut reads: Vec<(u32, Userdata)> = Vec::new();
let mut writes: Vec<(u32, Userdata)> = Vec::new();
let mut poll = Poll::new();
let subs = subs.as_array(nsubscriptions);
for sub_elem in subs.iter() {
let sub_ptr = sub_elem?;
let sub = sub_ptr.read()?;
match sub.u {
types::SubscriptionU::Clock(clocksub) => match clocksub.id {
types::Clockid::Monotonic => {
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.clocks
.creation_time
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
_ => Err(Error::invalid_argument()
.context("timer subscriptions only support monotonic timer"))?,
},
types::SubscriptionU::FdRead(readsub) => {
let fd = readsub.file_descriptor;
if sub_fds.contains(&fd) {
return Err(Error::invalid_argument()
.context("Fd can be subscribed to at most once per poll"));
} else {
sub_fds.insert(fd);
}
table
.get_file_mut(u32::from(fd))?
.get_cap_mut(FileCaps::POLL_READWRITE)?;
reads.push((u32::from(fd), sub.userdata.into()));
}
types::SubscriptionU::FdWrite(writesub) => {
let fd = writesub.file_descriptor;
if sub_fds.contains(&fd) {
return Err(Error::invalid_argument()
.context("Fd can be subscribed to at most once per poll"));
} else {
sub_fds.insert(fd);
}
table
.get_file_mut(u32::from(fd))?
.get_cap_mut(FileCaps::POLL_READWRITE)?;
writes.push((u32::from(fd), sub.userdata.into()));
}
}
}
self.sched.poll_oneoff(&mut poll).await?;
let results = poll.results();
let num_results = results.len();
assert!(
num_results <= nsubscriptions as usize,
"results exceeds subscriptions"
);
let events = events.as_array(
num_results
.try_into()
.expect("not greater than nsubscriptions"),
);
for ((result, userdata), event_elem) in results.into_iter().zip(events.iter()) {
let event_ptr = event_elem?;
let userdata: types::Userdata = userdata.into();
event_ptr.write(match result {
SubscriptionResult::Read(r) => {
let type_ = types::Eventtype::FdRead;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: types::Errno::from(e.downcast().map_err(Error::trap)?),
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::Write(r) => {
let type_ = types::Eventtype::FdWrite;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: types::Errno::from(e.downcast().map_err(Error::trap)?),
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::MonotonicClock(r) => {
let type_ = types::Eventtype::Clock;
types::Event {
userdata,
error: match r {
Ok(()) => types::Errno::Success,
Err(e) => types::Errno::from(e.downcast().map_err(Error::trap)?),
},
type_,
fd_readwrite: fd_readwrite_empty(),
}
}
})?;
}
Ok(num_results.try_into().expect("results fit into memory"))
}More examples
src/snapshots/preview_1.rs (lines 874-879)
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async fn poll_oneoff<'a>(
&mut self,
subs: &GuestPtr<'a, types::Subscription>,
events: &GuestPtr<'a, types::Event>,
nsubscriptions: types::Size,
) -> Result<types::Size, Error> {
if nsubscriptions == 0 {
return Err(Error::invalid_argument().context("nsubscriptions must be nonzero"));
}
// Special-case a `poll_oneoff` which is just sleeping on a single
// relative timer event, such as what WASI libc uses to implement sleep
// functions. This supports all clock IDs, because POSIX says that
// `clock_settime` doesn't effect relative sleeps.
if nsubscriptions == 1 {
let sub = subs.read()?;
if let types::SubscriptionU::Clock(clocksub) = sub.u {
if !clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.sched
.sleep(Duration::from_nanos(clocksub.timeout))
.await?;
events.write(types::Event {
userdata: sub.userdata,
error: types::Errno::Success,
type_: types::Eventtype::Clock,
fd_readwrite: fd_readwrite_empty(),
})?;
return Ok(1);
}
}
}
let table = &mut self.table;
// We need these refmuts to outlive Poll, which will hold the &mut dyn WasiFile inside
let mut read_refs: Vec<(&dyn WasiFile, Userdata)> = Vec::new();
let mut write_refs: Vec<(&dyn WasiFile, Userdata)> = Vec::new();
let mut poll = Poll::new();
let subs = subs.as_array(nsubscriptions);
for sub_elem in subs.iter() {
let sub_ptr = sub_elem?;
let sub = sub_ptr.read()?;
match sub.u {
types::SubscriptionU::Clock(clocksub) => match clocksub.id {
types::Clockid::Monotonic => {
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.clocks
.creation_time
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
types::Clockid::Realtime => {
// POSIX specifies that functions like `nanosleep` and others use the
// `REALTIME` clock. But it also says that `clock_settime` has no effect
// on threads waiting in these functions. MONOTONIC should always have
// resolution at least as good as REALTIME, so we can translate a
// non-absolute `REALTIME` request into a `MONOTONIC` request.
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
return Err(Error::not_supported());
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
_ => Err(Error::invalid_argument()
.context("timer subscriptions only support monotonic timer"))?,
},
types::SubscriptionU::FdRead(readsub) => {
let fd = readsub.file_descriptor;
let file_ref = table
.get_file(u32::from(fd))?
.get_cap(FileCaps::POLL_READWRITE)?;
read_refs.push((file_ref, sub.userdata.into()));
}
types::SubscriptionU::FdWrite(writesub) => {
let fd = writesub.file_descriptor;
let file_ref = table
.get_file(u32::from(fd))?
.get_cap(FileCaps::POLL_READWRITE)?;
write_refs.push((file_ref, sub.userdata.into()));
}
}
}
for (f, ud) in read_refs.iter_mut() {
poll.subscribe_read(*f, *ud);
}
for (f, ud) in write_refs.iter_mut() {
poll.subscribe_write(*f, *ud);
}
self.sched.poll_oneoff(&mut poll).await?;
let results = poll.results();
let num_results = results.len();
assert!(
num_results <= nsubscriptions as usize,
"results exceeds subscriptions"
);
let events = events.as_array(
num_results
.try_into()
.expect("not greater than nsubscriptions"),
);
for ((result, userdata), event_elem) in results.into_iter().zip(events.iter()) {
let event_ptr = event_elem?;
let userdata: types::Userdata = userdata.into();
event_ptr.write(match result {
SubscriptionResult::Read(r) => {
let type_ = types::Eventtype::FdRead;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: e.downcast().map_err(Error::trap)?,
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::Write(r) => {
let type_ = types::Eventtype::FdWrite;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: e.downcast().map_err(Error::trap)?,
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::MonotonicClock(r) => {
let type_ = types::Eventtype::Clock;
types::Event {
userdata,
error: match r {
Ok(()) => types::Errno::Success,
Err(e) => e.downcast().map_err(Error::trap)?,
},
type_,
fd_readwrite: fd_readwrite_empty(),
}
}
})?;
}
Ok(num_results.try_into().expect("results fit into memory"))
}sourcepub fn subscribe_read(&mut self, file: &'a dyn WasiFile, ud: Userdata)
pub fn subscribe_read(&mut self, file: &'a dyn WasiFile, ud: Userdata)
Examples found in repository?
src/snapshots/preview_1.rs (line 929)
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async fn poll_oneoff<'a>(
&mut self,
subs: &GuestPtr<'a, types::Subscription>,
events: &GuestPtr<'a, types::Event>,
nsubscriptions: types::Size,
) -> Result<types::Size, Error> {
if nsubscriptions == 0 {
return Err(Error::invalid_argument().context("nsubscriptions must be nonzero"));
}
// Special-case a `poll_oneoff` which is just sleeping on a single
// relative timer event, such as what WASI libc uses to implement sleep
// functions. This supports all clock IDs, because POSIX says that
// `clock_settime` doesn't effect relative sleeps.
if nsubscriptions == 1 {
let sub = subs.read()?;
if let types::SubscriptionU::Clock(clocksub) = sub.u {
if !clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.sched
.sleep(Duration::from_nanos(clocksub.timeout))
.await?;
events.write(types::Event {
userdata: sub.userdata,
error: types::Errno::Success,
type_: types::Eventtype::Clock,
fd_readwrite: fd_readwrite_empty(),
})?;
return Ok(1);
}
}
}
let table = &mut self.table;
// We need these refmuts to outlive Poll, which will hold the &mut dyn WasiFile inside
let mut read_refs: Vec<(&dyn WasiFile, Userdata)> = Vec::new();
let mut write_refs: Vec<(&dyn WasiFile, Userdata)> = Vec::new();
let mut poll = Poll::new();
let subs = subs.as_array(nsubscriptions);
for sub_elem in subs.iter() {
let sub_ptr = sub_elem?;
let sub = sub_ptr.read()?;
match sub.u {
types::SubscriptionU::Clock(clocksub) => match clocksub.id {
types::Clockid::Monotonic => {
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.clocks
.creation_time
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
types::Clockid::Realtime => {
// POSIX specifies that functions like `nanosleep` and others use the
// `REALTIME` clock. But it also says that `clock_settime` has no effect
// on threads waiting in these functions. MONOTONIC should always have
// resolution at least as good as REALTIME, so we can translate a
// non-absolute `REALTIME` request into a `MONOTONIC` request.
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
return Err(Error::not_supported());
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
_ => Err(Error::invalid_argument()
.context("timer subscriptions only support monotonic timer"))?,
},
types::SubscriptionU::FdRead(readsub) => {
let fd = readsub.file_descriptor;
let file_ref = table
.get_file(u32::from(fd))?
.get_cap(FileCaps::POLL_READWRITE)?;
read_refs.push((file_ref, sub.userdata.into()));
}
types::SubscriptionU::FdWrite(writesub) => {
let fd = writesub.file_descriptor;
let file_ref = table
.get_file(u32::from(fd))?
.get_cap(FileCaps::POLL_READWRITE)?;
write_refs.push((file_ref, sub.userdata.into()));
}
}
}
for (f, ud) in read_refs.iter_mut() {
poll.subscribe_read(*f, *ud);
}
for (f, ud) in write_refs.iter_mut() {
poll.subscribe_write(*f, *ud);
}
self.sched.poll_oneoff(&mut poll).await?;
let results = poll.results();
let num_results = results.len();
assert!(
num_results <= nsubscriptions as usize,
"results exceeds subscriptions"
);
let events = events.as_array(
num_results
.try_into()
.expect("not greater than nsubscriptions"),
);
for ((result, userdata), event_elem) in results.into_iter().zip(events.iter()) {
let event_ptr = event_elem?;
let userdata: types::Userdata = userdata.into();
event_ptr.write(match result {
SubscriptionResult::Read(r) => {
let type_ = types::Eventtype::FdRead;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: e.downcast().map_err(Error::trap)?,
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::Write(r) => {
let type_ = types::Eventtype::FdWrite;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: e.downcast().map_err(Error::trap)?,
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::MonotonicClock(r) => {
let type_ = types::Eventtype::Clock;
types::Event {
userdata,
error: match r {
Ok(()) => types::Errno::Success,
Err(e) => e.downcast().map_err(Error::trap)?,
},
type_,
fd_readwrite: fd_readwrite_empty(),
}
}
})?;
}
Ok(num_results.try_into().expect("results fit into memory"))
}sourcepub fn subscribe_write(&mut self, file: &'a dyn WasiFile, ud: Userdata)
pub fn subscribe_write(&mut self, file: &'a dyn WasiFile, ud: Userdata)
Examples found in repository?
src/snapshots/preview_1.rs (line 932)
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async fn poll_oneoff<'a>(
&mut self,
subs: &GuestPtr<'a, types::Subscription>,
events: &GuestPtr<'a, types::Event>,
nsubscriptions: types::Size,
) -> Result<types::Size, Error> {
if nsubscriptions == 0 {
return Err(Error::invalid_argument().context("nsubscriptions must be nonzero"));
}
// Special-case a `poll_oneoff` which is just sleeping on a single
// relative timer event, such as what WASI libc uses to implement sleep
// functions. This supports all clock IDs, because POSIX says that
// `clock_settime` doesn't effect relative sleeps.
if nsubscriptions == 1 {
let sub = subs.read()?;
if let types::SubscriptionU::Clock(clocksub) = sub.u {
if !clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.sched
.sleep(Duration::from_nanos(clocksub.timeout))
.await?;
events.write(types::Event {
userdata: sub.userdata,
error: types::Errno::Success,
type_: types::Eventtype::Clock,
fd_readwrite: fd_readwrite_empty(),
})?;
return Ok(1);
}
}
}
let table = &mut self.table;
// We need these refmuts to outlive Poll, which will hold the &mut dyn WasiFile inside
let mut read_refs: Vec<(&dyn WasiFile, Userdata)> = Vec::new();
let mut write_refs: Vec<(&dyn WasiFile, Userdata)> = Vec::new();
let mut poll = Poll::new();
let subs = subs.as_array(nsubscriptions);
for sub_elem in subs.iter() {
let sub_ptr = sub_elem?;
let sub = sub_ptr.read()?;
match sub.u {
types::SubscriptionU::Clock(clocksub) => match clocksub.id {
types::Clockid::Monotonic => {
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.clocks
.creation_time
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
types::Clockid::Realtime => {
// POSIX specifies that functions like `nanosleep` and others use the
// `REALTIME` clock. But it also says that `clock_settime` has no effect
// on threads waiting in these functions. MONOTONIC should always have
// resolution at least as good as REALTIME, so we can translate a
// non-absolute `REALTIME` request into a `MONOTONIC` request.
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
return Err(Error::not_supported());
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
_ => Err(Error::invalid_argument()
.context("timer subscriptions only support monotonic timer"))?,
},
types::SubscriptionU::FdRead(readsub) => {
let fd = readsub.file_descriptor;
let file_ref = table
.get_file(u32::from(fd))?
.get_cap(FileCaps::POLL_READWRITE)?;
read_refs.push((file_ref, sub.userdata.into()));
}
types::SubscriptionU::FdWrite(writesub) => {
let fd = writesub.file_descriptor;
let file_ref = table
.get_file(u32::from(fd))?
.get_cap(FileCaps::POLL_READWRITE)?;
write_refs.push((file_ref, sub.userdata.into()));
}
}
}
for (f, ud) in read_refs.iter_mut() {
poll.subscribe_read(*f, *ud);
}
for (f, ud) in write_refs.iter_mut() {
poll.subscribe_write(*f, *ud);
}
self.sched.poll_oneoff(&mut poll).await?;
let results = poll.results();
let num_results = results.len();
assert!(
num_results <= nsubscriptions as usize,
"results exceeds subscriptions"
);
let events = events.as_array(
num_results
.try_into()
.expect("not greater than nsubscriptions"),
);
for ((result, userdata), event_elem) in results.into_iter().zip(events.iter()) {
let event_ptr = event_elem?;
let userdata: types::Userdata = userdata.into();
event_ptr.write(match result {
SubscriptionResult::Read(r) => {
let type_ = types::Eventtype::FdRead;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: e.downcast().map_err(Error::trap)?,
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::Write(r) => {
let type_ = types::Eventtype::FdWrite;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: e.downcast().map_err(Error::trap)?,
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::MonotonicClock(r) => {
let type_ = types::Eventtype::Clock;
types::Event {
userdata,
error: match r {
Ok(()) => types::Errno::Success,
Err(e) => e.downcast().map_err(Error::trap)?,
},
type_,
fd_readwrite: fd_readwrite_empty(),
}
}
})?;
}
Ok(num_results.try_into().expect("results fit into memory"))
}sourcepub fn results(self) -> Vec<(SubscriptionResult, Userdata)>
pub fn results(self) -> Vec<(SubscriptionResult, Userdata)>
Examples found in repository?
src/snapshots/preview_0.rs (line 949)
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async fn poll_oneoff<'a>(
&mut self,
subs: &GuestPtr<'a, types::Subscription>,
events: &GuestPtr<'a, types::Event>,
nsubscriptions: types::Size,
) -> Result<types::Size, Error> {
if nsubscriptions == 0 {
return Err(Error::invalid_argument().context("nsubscriptions must be nonzero"));
}
// Special-case a `poll_oneoff` which is just sleeping on a single
// relative timer event, such as what WASI libc uses to implement sleep
// functions. This supports all clock IDs, because POSIX says that
// `clock_settime` doesn't effect relative sleeps.
if nsubscriptions == 1 {
let sub = subs.read()?;
if let types::SubscriptionU::Clock(clocksub) = sub.u {
if !clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.sched
.sleep(Duration::from_nanos(clocksub.timeout))
.await?;
events.write(types::Event {
userdata: sub.userdata,
error: types::Errno::Success,
type_: types::Eventtype::Clock,
fd_readwrite: fd_readwrite_empty(),
})?;
return Ok(1);
}
}
}
let table = &mut self.table;
let mut sub_fds: HashSet<types::Fd> = HashSet::new();
// We need these refmuts to outlive Poll, which will hold the &mut dyn WasiFile inside
let mut reads: Vec<(u32, Userdata)> = Vec::new();
let mut writes: Vec<(u32, Userdata)> = Vec::new();
let mut poll = Poll::new();
let subs = subs.as_array(nsubscriptions);
for sub_elem in subs.iter() {
let sub_ptr = sub_elem?;
let sub = sub_ptr.read()?;
match sub.u {
types::SubscriptionU::Clock(clocksub) => match clocksub.id {
types::Clockid::Monotonic => {
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.clocks
.creation_time
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
_ => Err(Error::invalid_argument()
.context("timer subscriptions only support monotonic timer"))?,
},
types::SubscriptionU::FdRead(readsub) => {
let fd = readsub.file_descriptor;
if sub_fds.contains(&fd) {
return Err(Error::invalid_argument()
.context("Fd can be subscribed to at most once per poll"));
} else {
sub_fds.insert(fd);
}
table
.get_file_mut(u32::from(fd))?
.get_cap_mut(FileCaps::POLL_READWRITE)?;
reads.push((u32::from(fd), sub.userdata.into()));
}
types::SubscriptionU::FdWrite(writesub) => {
let fd = writesub.file_descriptor;
if sub_fds.contains(&fd) {
return Err(Error::invalid_argument()
.context("Fd can be subscribed to at most once per poll"));
} else {
sub_fds.insert(fd);
}
table
.get_file_mut(u32::from(fd))?
.get_cap_mut(FileCaps::POLL_READWRITE)?;
writes.push((u32::from(fd), sub.userdata.into()));
}
}
}
self.sched.poll_oneoff(&mut poll).await?;
let results = poll.results();
let num_results = results.len();
assert!(
num_results <= nsubscriptions as usize,
"results exceeds subscriptions"
);
let events = events.as_array(
num_results
.try_into()
.expect("not greater than nsubscriptions"),
);
for ((result, userdata), event_elem) in results.into_iter().zip(events.iter()) {
let event_ptr = event_elem?;
let userdata: types::Userdata = userdata.into();
event_ptr.write(match result {
SubscriptionResult::Read(r) => {
let type_ = types::Eventtype::FdRead;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: types::Errno::from(e.downcast().map_err(Error::trap)?),
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::Write(r) => {
let type_ = types::Eventtype::FdWrite;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: types::Errno::from(e.downcast().map_err(Error::trap)?),
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::MonotonicClock(r) => {
let type_ = types::Eventtype::Clock;
types::Event {
userdata,
error: match r {
Ok(()) => types::Errno::Success,
Err(e) => types::Errno::from(e.downcast().map_err(Error::trap)?),
},
type_,
fd_readwrite: fd_readwrite_empty(),
}
}
})?;
}
Ok(num_results.try_into().expect("results fit into memory"))
}More examples
src/snapshots/preview_1.rs (line 937)
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async fn poll_oneoff<'a>(
&mut self,
subs: &GuestPtr<'a, types::Subscription>,
events: &GuestPtr<'a, types::Event>,
nsubscriptions: types::Size,
) -> Result<types::Size, Error> {
if nsubscriptions == 0 {
return Err(Error::invalid_argument().context("nsubscriptions must be nonzero"));
}
// Special-case a `poll_oneoff` which is just sleeping on a single
// relative timer event, such as what WASI libc uses to implement sleep
// functions. This supports all clock IDs, because POSIX says that
// `clock_settime` doesn't effect relative sleeps.
if nsubscriptions == 1 {
let sub = subs.read()?;
if let types::SubscriptionU::Clock(clocksub) = sub.u {
if !clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.sched
.sleep(Duration::from_nanos(clocksub.timeout))
.await?;
events.write(types::Event {
userdata: sub.userdata,
error: types::Errno::Success,
type_: types::Eventtype::Clock,
fd_readwrite: fd_readwrite_empty(),
})?;
return Ok(1);
}
}
}
let table = &mut self.table;
// We need these refmuts to outlive Poll, which will hold the &mut dyn WasiFile inside
let mut read_refs: Vec<(&dyn WasiFile, Userdata)> = Vec::new();
let mut write_refs: Vec<(&dyn WasiFile, Userdata)> = Vec::new();
let mut poll = Poll::new();
let subs = subs.as_array(nsubscriptions);
for sub_elem in subs.iter() {
let sub_ptr = sub_elem?;
let sub = sub_ptr.read()?;
match sub.u {
types::SubscriptionU::Clock(clocksub) => match clocksub.id {
types::Clockid::Monotonic => {
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
self.clocks
.creation_time
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
types::Clockid::Realtime => {
// POSIX specifies that functions like `nanosleep` and others use the
// `REALTIME` clock. But it also says that `clock_settime` has no effect
// on threads waiting in these functions. MONOTONIC should always have
// resolution at least as good as REALTIME, so we can translate a
// non-absolute `REALTIME` request into a `MONOTONIC` request.
let clock = self.clocks.monotonic.deref();
let precision = Duration::from_nanos(clocksub.precision);
let duration = Duration::from_nanos(clocksub.timeout);
let deadline = if clocksub
.flags
.contains(types::Subclockflags::SUBSCRIPTION_CLOCK_ABSTIME)
{
return Err(Error::not_supported());
} else {
clock
.now(precision)
.checked_add(duration)
.ok_or_else(|| Error::overflow().context("deadline"))?
};
poll.subscribe_monotonic_clock(
clock,
deadline,
precision,
sub.userdata.into(),
)
}
_ => Err(Error::invalid_argument()
.context("timer subscriptions only support monotonic timer"))?,
},
types::SubscriptionU::FdRead(readsub) => {
let fd = readsub.file_descriptor;
let file_ref = table
.get_file(u32::from(fd))?
.get_cap(FileCaps::POLL_READWRITE)?;
read_refs.push((file_ref, sub.userdata.into()));
}
types::SubscriptionU::FdWrite(writesub) => {
let fd = writesub.file_descriptor;
let file_ref = table
.get_file(u32::from(fd))?
.get_cap(FileCaps::POLL_READWRITE)?;
write_refs.push((file_ref, sub.userdata.into()));
}
}
}
for (f, ud) in read_refs.iter_mut() {
poll.subscribe_read(*f, *ud);
}
for (f, ud) in write_refs.iter_mut() {
poll.subscribe_write(*f, *ud);
}
self.sched.poll_oneoff(&mut poll).await?;
let results = poll.results();
let num_results = results.len();
assert!(
num_results <= nsubscriptions as usize,
"results exceeds subscriptions"
);
let events = events.as_array(
num_results
.try_into()
.expect("not greater than nsubscriptions"),
);
for ((result, userdata), event_elem) in results.into_iter().zip(events.iter()) {
let event_ptr = event_elem?;
let userdata: types::Userdata = userdata.into();
event_ptr.write(match result {
SubscriptionResult::Read(r) => {
let type_ = types::Eventtype::FdRead;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: e.downcast().map_err(Error::trap)?,
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::Write(r) => {
let type_ = types::Eventtype::FdWrite;
match r {
Ok((nbytes, flags)) => types::Event {
userdata,
error: types::Errno::Success,
type_,
fd_readwrite: types::EventFdReadwrite {
nbytes,
flags: types::Eventrwflags::from(&flags),
},
},
Err(e) => types::Event {
userdata,
error: e.downcast().map_err(Error::trap)?,
type_,
fd_readwrite: fd_readwrite_empty(),
},
}
}
SubscriptionResult::MonotonicClock(r) => {
let type_ = types::Eventtype::Clock;
types::Event {
userdata,
error: match r {
Ok(()) => types::Errno::Success,
Err(e) => e.downcast().map_err(Error::trap)?,
},
type_,
fd_readwrite: fd_readwrite_empty(),
}
}
})?;
}
Ok(num_results.try_into().expect("results fit into memory"))
}