fidl_fuchsia_memorypressure/

fidl_fuchsia_memorypressure.rs

// WARNING: This file is machine generated by fidlgen.

#![warn(clippy::all)]
#![allow(unused_parens, unused_mut, unused_imports, nonstandard_style)]

use bitflags::bitflags;
use fidl::client::QueryResponseFut;
use fidl::encoding::{MessageBufFor, ProxyChannelBox, ResourceDialect};
use fidl::endpoints::{ControlHandle as _, Responder as _};
pub use fidl_fuchsia_memorypressure__common::*;
use futures::future::{self, MaybeDone, TryFutureExt};
use zx_status;

#[derive(Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
pub struct ProviderRegisterWatcherRequest {
    pub watcher: fidl::endpoints::ClientEnd<WatcherMarker>,
}

impl fidl::Standalone<fidl::encoding::DefaultFuchsiaResourceDialect>
    for ProviderRegisterWatcherRequest
{
}

#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub struct ProviderMarker;

impl fidl::endpoints::ProtocolMarker for ProviderMarker {
    type Proxy = ProviderProxy;
    type RequestStream = ProviderRequestStream;
    #[cfg(target_os = "fuchsia")]
    type SynchronousProxy = ProviderSynchronousProxy;

    const DEBUG_NAME: &'static str = "fuchsia.memorypressure.Provider";
}
impl fidl::endpoints::DiscoverableProtocolMarker for ProviderMarker {}

pub trait ProviderProxyInterface: Send + Sync {
    fn r#register_watcher(
        &self,
        watcher: fidl::endpoints::ClientEnd<WatcherMarker>,
    ) -> Result<(), fidl::Error>;
}
#[derive(Debug)]
#[cfg(target_os = "fuchsia")]
pub struct ProviderSynchronousProxy {
    client: fidl::client::sync::Client,
}

#[cfg(target_os = "fuchsia")]
impl fidl::endpoints::SynchronousProxy for ProviderSynchronousProxy {
    type Proxy = ProviderProxy;
    type Protocol = ProviderMarker;

    fn from_channel(inner: fidl::Channel) -> Self {
        Self::new(inner)
    }

    fn into_channel(self) -> fidl::Channel {
        self.client.into_channel()
    }

    fn as_channel(&self) -> &fidl::Channel {
        self.client.as_channel()
    }
}

#[cfg(target_os = "fuchsia")]
impl ProviderSynchronousProxy {
    pub fn new(channel: fidl::Channel) -> Self {
        Self { client: fidl::client::sync::Client::new(channel) }
    }

    pub fn into_channel(self) -> fidl::Channel {
        self.client.into_channel()
    }

    /// Waits until an event arrives and returns it. It is safe for other
    /// threads to make concurrent requests while waiting for an event.
    pub fn wait_for_event(
        &self,
        deadline: zx::MonotonicInstant,
    ) -> Result<ProviderEvent, fidl::Error> {
        ProviderEvent::decode(self.client.wait_for_event::<ProviderMarker>(deadline)?)
    }

    /// Used to register for memory pressure level changes.
    /// `watcher`: memory pressure `Watcher` channel that the `Provider` will use to send
    /// level change messages to the client.
    ///
    /// The current memory pressure level is immediately sent to the watcher
    /// when this method is called.
    ///
    /// It is recommended that the root job in a component tree register for changes,
    /// rather than having individual jobs further down the tree register individually.
    /// A low client count will help minimize system churn due to a large number of
    /// memory pressure messages in transit at the same time.
    /// Also, the more context a job has, the better equipped it will be to react to
    /// memory pressure by controlling the behavior of children jobs in its tree.
    pub fn r#register_watcher(
        &self,
        mut watcher: fidl::endpoints::ClientEnd<WatcherMarker>,
    ) -> Result<(), fidl::Error> {
        self.client.send::<ProviderRegisterWatcherRequest>(
            (watcher,),
            0x91e65af25aae4a9,
            fidl::encoding::DynamicFlags::empty(),
        )
    }
}

#[cfg(target_os = "fuchsia")]
impl From<ProviderSynchronousProxy> for zx::NullableHandle {
    fn from(value: ProviderSynchronousProxy) -> Self {
        value.into_channel().into()
    }
}

#[cfg(target_os = "fuchsia")]
impl From<fidl::Channel> for ProviderSynchronousProxy {
    fn from(value: fidl::Channel) -> Self {
        Self::new(value)
    }
}

#[cfg(target_os = "fuchsia")]
impl fidl::endpoints::FromClient for ProviderSynchronousProxy {
    type Protocol = ProviderMarker;

    fn from_client(value: fidl::endpoints::ClientEnd<ProviderMarker>) -> Self {
        Self::new(value.into_channel())
    }
}

#[derive(Debug, Clone)]
pub struct ProviderProxy {
    client: fidl::client::Client<fidl::encoding::DefaultFuchsiaResourceDialect>,
}

impl fidl::endpoints::Proxy for ProviderProxy {
    type Protocol = ProviderMarker;

    fn from_channel(inner: ::fidl::AsyncChannel) -> Self {
        Self::new(inner)
    }

    fn into_channel(self) -> Result<::fidl::AsyncChannel, Self> {
        self.client.into_channel().map_err(|client| Self { client })
    }

    fn as_channel(&self) -> &::fidl::AsyncChannel {
        self.client.as_channel()
    }
}

impl ProviderProxy {
    /// Create a new Proxy for fuchsia.memorypressure/Provider.
    pub fn new(channel: ::fidl::AsyncChannel) -> Self {
        let protocol_name = <ProviderMarker as fidl::endpoints::ProtocolMarker>::DEBUG_NAME;
        Self { client: fidl::client::Client::new(channel, protocol_name) }
    }

    /// Get a Stream of events from the remote end of the protocol.
    ///
    /// # Panics
    ///
    /// Panics if the event stream was already taken.
    pub fn take_event_stream(&self) -> ProviderEventStream {
        ProviderEventStream { event_receiver: self.client.take_event_receiver() }
    }

    /// Used to register for memory pressure level changes.
    /// `watcher`: memory pressure `Watcher` channel that the `Provider` will use to send
    /// level change messages to the client.
    ///
    /// The current memory pressure level is immediately sent to the watcher
    /// when this method is called.
    ///
    /// It is recommended that the root job in a component tree register for changes,
    /// rather than having individual jobs further down the tree register individually.
    /// A low client count will help minimize system churn due to a large number of
    /// memory pressure messages in transit at the same time.
    /// Also, the more context a job has, the better equipped it will be to react to
    /// memory pressure by controlling the behavior of children jobs in its tree.
    pub fn r#register_watcher(
        &self,
        mut watcher: fidl::endpoints::ClientEnd<WatcherMarker>,
    ) -> Result<(), fidl::Error> {
        ProviderProxyInterface::r#register_watcher(self, watcher)
    }
}

impl ProviderProxyInterface for ProviderProxy {
    fn r#register_watcher(
        &self,
        mut watcher: fidl::endpoints::ClientEnd<WatcherMarker>,
    ) -> Result<(), fidl::Error> {
        self.client.send::<ProviderRegisterWatcherRequest>(
            (watcher,),
            0x91e65af25aae4a9,
            fidl::encoding::DynamicFlags::empty(),
        )
    }
}

pub struct ProviderEventStream {
    event_receiver: fidl::client::EventReceiver<fidl::encoding::DefaultFuchsiaResourceDialect>,
}

impl std::marker::Unpin for ProviderEventStream {}

impl futures::stream::FusedStream for ProviderEventStream {
    fn is_terminated(&self) -> bool {
        self.event_receiver.is_terminated()
    }
}

impl futures::Stream for ProviderEventStream {
    type Item = Result<ProviderEvent, fidl::Error>;

    fn poll_next(
        mut self: std::pin::Pin<&mut Self>,
        cx: &mut std::task::Context<'_>,
    ) -> std::task::Poll<Option<Self::Item>> {
        match futures::ready!(futures::stream::StreamExt::poll_next_unpin(
            &mut self.event_receiver,
            cx
        )?) {
            Some(buf) => std::task::Poll::Ready(Some(ProviderEvent::decode(buf))),
            None => std::task::Poll::Ready(None),
        }
    }
}

#[derive(Debug)]
pub enum ProviderEvent {}

impl ProviderEvent {
    /// Decodes a message buffer as a [`ProviderEvent`].
    fn decode(
        mut buf: <fidl::encoding::DefaultFuchsiaResourceDialect as fidl::encoding::ResourceDialect>::MessageBufEtc,
    ) -> Result<ProviderEvent, fidl::Error> {
        let (bytes, _handles) = buf.split_mut();
        let (tx_header, _body_bytes) = fidl::encoding::decode_transaction_header(bytes)?;
        debug_assert_eq!(tx_header.tx_id, 0);
        match tx_header.ordinal {
            _ => Err(fidl::Error::UnknownOrdinal {
                ordinal: tx_header.ordinal,
                protocol_name: <ProviderMarker as fidl::endpoints::ProtocolMarker>::DEBUG_NAME,
            }),
        }
    }
}

/// A Stream of incoming requests for fuchsia.memorypressure/Provider.
pub struct ProviderRequestStream {
    inner: std::sync::Arc<fidl::ServeInner<fidl::encoding::DefaultFuchsiaResourceDialect>>,
    is_terminated: bool,
}

impl std::marker::Unpin for ProviderRequestStream {}

impl futures::stream::FusedStream for ProviderRequestStream {
    fn is_terminated(&self) -> bool {
        self.is_terminated
    }
}

impl fidl::endpoints::RequestStream for ProviderRequestStream {
    type Protocol = ProviderMarker;
    type ControlHandle = ProviderControlHandle;

    fn from_channel(channel: ::fidl::AsyncChannel) -> Self {
        Self { inner: std::sync::Arc::new(fidl::ServeInner::new(channel)), is_terminated: false }
    }

    fn control_handle(&self) -> Self::ControlHandle {
        ProviderControlHandle { inner: self.inner.clone() }
    }

    fn into_inner(
        self,
    ) -> (::std::sync::Arc<fidl::ServeInner<fidl::encoding::DefaultFuchsiaResourceDialect>>, bool)
    {
        (self.inner, self.is_terminated)
    }

    fn from_inner(
        inner: std::sync::Arc<fidl::ServeInner<fidl::encoding::DefaultFuchsiaResourceDialect>>,
        is_terminated: bool,
    ) -> Self {
        Self { inner, is_terminated }
    }
}

impl futures::Stream for ProviderRequestStream {
    type Item = Result<ProviderRequest, fidl::Error>;

    fn poll_next(
        mut self: std::pin::Pin<&mut Self>,
        cx: &mut std::task::Context<'_>,
    ) -> std::task::Poll<Option<Self::Item>> {
        let this = &mut *self;
        if this.inner.check_shutdown(cx) {
            this.is_terminated = true;
            return std::task::Poll::Ready(None);
        }
        if this.is_terminated {
            panic!("polled ProviderRequestStream after completion");
        }
        fidl::encoding::with_tls_decode_buf::<_, fidl::encoding::DefaultFuchsiaResourceDialect>(
            |bytes, handles| {
                match this.inner.channel().read_etc(cx, bytes, handles) {
                    std::task::Poll::Ready(Ok(())) => {}
                    std::task::Poll::Pending => return std::task::Poll::Pending,
                    std::task::Poll::Ready(Err(zx_status::Status::PEER_CLOSED)) => {
                        this.is_terminated = true;
                        return std::task::Poll::Ready(None);
                    }
                    std::task::Poll::Ready(Err(e)) => {
                        return std::task::Poll::Ready(Some(Err(fidl::Error::ServerRequestRead(
                            e.into(),
                        ))));
                    }
                }

                // A message has been received from the channel
                let (header, _body_bytes) = fidl::encoding::decode_transaction_header(bytes)?;

                std::task::Poll::Ready(Some(match header.ordinal {
                    0x91e65af25aae4a9 => {
                        header.validate_request_tx_id(fidl::MethodType::OneWay)?;
                        let mut req = fidl::new_empty!(
                            ProviderRegisterWatcherRequest,
                            fidl::encoding::DefaultFuchsiaResourceDialect
                        );
                        fidl::encoding::Decoder::<fidl::encoding::DefaultFuchsiaResourceDialect>::decode_into::<ProviderRegisterWatcherRequest>(&header, _body_bytes, handles, &mut req)?;
                        let control_handle = ProviderControlHandle { inner: this.inner.clone() };
                        Ok(ProviderRequest::RegisterWatcher {
                            watcher: req.watcher,

                            control_handle,
                        })
                    }
                    _ => Err(fidl::Error::UnknownOrdinal {
                        ordinal: header.ordinal,
                        protocol_name:
                            <ProviderMarker as fidl::endpoints::ProtocolMarker>::DEBUG_NAME,
                    }),
                }))
            },
        )
    }
}

/// Registration protocol
#[derive(Debug)]
pub enum ProviderRequest {
    /// Used to register for memory pressure level changes.
    /// `watcher`: memory pressure `Watcher` channel that the `Provider` will use to send
    /// level change messages to the client.
    ///
    /// The current memory pressure level is immediately sent to the watcher
    /// when this method is called.
    ///
    /// It is recommended that the root job in a component tree register for changes,
    /// rather than having individual jobs further down the tree register individually.
    /// A low client count will help minimize system churn due to a large number of
    /// memory pressure messages in transit at the same time.
    /// Also, the more context a job has, the better equipped it will be to react to
    /// memory pressure by controlling the behavior of children jobs in its tree.
    RegisterWatcher {
        watcher: fidl::endpoints::ClientEnd<WatcherMarker>,
        control_handle: ProviderControlHandle,
    },
}

impl ProviderRequest {
    #[allow(irrefutable_let_patterns)]
    pub fn into_register_watcher(
        self,
    ) -> Option<(fidl::endpoints::ClientEnd<WatcherMarker>, ProviderControlHandle)> {
        if let ProviderRequest::RegisterWatcher { watcher, control_handle } = self {
            Some((watcher, control_handle))
        } else {
            None
        }
    }

    /// Name of the method defined in FIDL
    pub fn method_name(&self) -> &'static str {
        match *self {
            ProviderRequest::RegisterWatcher { .. } => "register_watcher",
        }
    }
}

#[derive(Debug, Clone)]
pub struct ProviderControlHandle {
    inner: std::sync::Arc<fidl::ServeInner<fidl::encoding::DefaultFuchsiaResourceDialect>>,
}

impl fidl::endpoints::ControlHandle for ProviderControlHandle {
    fn shutdown(&self) {
        self.inner.shutdown()
    }

    fn shutdown_with_epitaph(&self, status: zx_status::Status) {
        self.inner.shutdown_with_epitaph(status)
    }

    fn is_closed(&self) -> bool {
        self.inner.channel().is_closed()
    }
    fn on_closed(&self) -> fidl::OnSignalsRef<'_> {
        self.inner.channel().on_closed()
    }

    #[cfg(target_os = "fuchsia")]
    fn signal_peer(
        &self,
        clear_mask: zx::Signals,
        set_mask: zx::Signals,
    ) -> Result<(), zx_status::Status> {
        use fidl::Peered;
        self.inner.channel().signal_peer(clear_mask, set_mask)
    }
}

impl ProviderControlHandle {}

#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub struct WatcherMarker;

impl fidl::endpoints::ProtocolMarker for WatcherMarker {
    type Proxy = WatcherProxy;
    type RequestStream = WatcherRequestStream;
    #[cfg(target_os = "fuchsia")]
    type SynchronousProxy = WatcherSynchronousProxy;

    const DEBUG_NAME: &'static str = "(anonymous) Watcher";
}

pub trait WatcherProxyInterface: Send + Sync {
    type OnLevelChangedResponseFut: std::future::Future<Output = Result<(), fidl::Error>> + Send;
    fn r#on_level_changed(&self, level: Level) -> Self::OnLevelChangedResponseFut;
}
#[derive(Debug)]
#[cfg(target_os = "fuchsia")]
pub struct WatcherSynchronousProxy {
    client: fidl::client::sync::Client,
}

#[cfg(target_os = "fuchsia")]
impl fidl::endpoints::SynchronousProxy for WatcherSynchronousProxy {
    type Proxy = WatcherProxy;
    type Protocol = WatcherMarker;

    fn from_channel(inner: fidl::Channel) -> Self {
        Self::new(inner)
    }

    fn into_channel(self) -> fidl::Channel {
        self.client.into_channel()
    }

    fn as_channel(&self) -> &fidl::Channel {
        self.client.as_channel()
    }
}

#[cfg(target_os = "fuchsia")]
impl WatcherSynchronousProxy {
    pub fn new(channel: fidl::Channel) -> Self {
        Self { client: fidl::client::sync::Client::new(channel) }
    }

    pub fn into_channel(self) -> fidl::Channel {
        self.client.into_channel()
    }

    /// Waits until an event arrives and returns it. It is safe for other
    /// threads to make concurrent requests while waiting for an event.
    pub fn wait_for_event(
        &self,
        deadline: zx::MonotonicInstant,
    ) -> Result<WatcherEvent, fidl::Error> {
        WatcherEvent::decode(self.client.wait_for_event::<WatcherMarker>(deadline)?)
    }

    /// Sent to the registered client when the memory pressure level changes.
    /// `level`: indicates the current memory pressure level.
    ///
    /// Will also be invoked on initial connection via `RegisterWatcher`, so that a newly
    /// registered client can discover the current memory pressure level.
    ///
    /// The watcher must immediately reply with a message to acknowledge that it has
    /// received the level change notification, and has initiated required actions as a
    /// result. It may then continue to reclaim memory asynchronously after sending
    /// the acknowledgement.
    ///
    /// Some helpful guidelines for clients:
    /// 1. The watcher will be notified of new pressure level changes only after a reply
    /// corresponding to the previous message has been received by the provider.
    /// If multiple level transitions occur during that time, the watcher will be
    /// notified of the latest pressure level.
    ///
    /// 2. The level changes are edge-triggered, and clients are expected to maintain
    /// local state to track the current pressure level, if required. For example,
    /// a job might be notified of a CRITICAL level and drop all its caches as a result.
    /// Some time after this, it might want to trigger an activity that causes a
    /// fair amount of memory to be allocated. At this point, the job is expected to
    /// remember that the last pressure level it saw was CRITICAL, and refrain from
    /// triggering the memory-intensive activity.
    ///
    /// 3. As a performance optimization, the provider may decide to skip sending
    /// messages for some pressure level changes. For example, when oscillating across
    /// the NORMAL / WARNING boundary, it might not be worth notifying clients of every
    /// single transition. The provider might rate-limit messages in this case.
    /// On a similar note, the provider may decide to send repeated messages at the
    /// same pressure level, particularly CRITICAL, to indicate that further action
    /// needs to be taken.
    pub fn r#on_level_changed(
        &self,
        mut level: Level,
        ___deadline: zx::MonotonicInstant,
    ) -> Result<(), fidl::Error> {
        let _response = self.client.send_query::<
            WatcherOnLevelChangedRequest,
            fidl::encoding::EmptyPayload,
            WatcherMarker,
        >(
            (level,),
            0x55d559533407fed9,
            fidl::encoding::DynamicFlags::empty(),
            ___deadline,
        )?;
        Ok(_response)
    }
}

#[cfg(target_os = "fuchsia")]
impl From<WatcherSynchronousProxy> for zx::NullableHandle {
    fn from(value: WatcherSynchronousProxy) -> Self {
        value.into_channel().into()
    }
}

#[cfg(target_os = "fuchsia")]
impl From<fidl::Channel> for WatcherSynchronousProxy {
    fn from(value: fidl::Channel) -> Self {
        Self::new(value)
    }
}

#[cfg(target_os = "fuchsia")]
impl fidl::endpoints::FromClient for WatcherSynchronousProxy {
    type Protocol = WatcherMarker;

    fn from_client(value: fidl::endpoints::ClientEnd<WatcherMarker>) -> Self {
        Self::new(value.into_channel())
    }
}

#[derive(Debug, Clone)]
pub struct WatcherProxy {
    client: fidl::client::Client<fidl::encoding::DefaultFuchsiaResourceDialect>,
}

impl fidl::endpoints::Proxy for WatcherProxy {
    type Protocol = WatcherMarker;

    fn from_channel(inner: ::fidl::AsyncChannel) -> Self {
        Self::new(inner)
    }

    fn into_channel(self) -> Result<::fidl::AsyncChannel, Self> {
        self.client.into_channel().map_err(|client| Self { client })
    }

    fn as_channel(&self) -> &::fidl::AsyncChannel {
        self.client.as_channel()
    }
}

impl WatcherProxy {
    /// Create a new Proxy for fuchsia.memorypressure/Watcher.
    pub fn new(channel: ::fidl::AsyncChannel) -> Self {
        let protocol_name = <WatcherMarker as fidl::endpoints::ProtocolMarker>::DEBUG_NAME;
        Self { client: fidl::client::Client::new(channel, protocol_name) }
    }

    /// Get a Stream of events from the remote end of the protocol.
    ///
    /// # Panics
    ///
    /// Panics if the event stream was already taken.
    pub fn take_event_stream(&self) -> WatcherEventStream {
        WatcherEventStream { event_receiver: self.client.take_event_receiver() }
    }

    /// Sent to the registered client when the memory pressure level changes.
    /// `level`: indicates the current memory pressure level.
    ///
    /// Will also be invoked on initial connection via `RegisterWatcher`, so that a newly
    /// registered client can discover the current memory pressure level.
    ///
    /// The watcher must immediately reply with a message to acknowledge that it has
    /// received the level change notification, and has initiated required actions as a
    /// result. It may then continue to reclaim memory asynchronously after sending
    /// the acknowledgement.
    ///
    /// Some helpful guidelines for clients:
    /// 1. The watcher will be notified of new pressure level changes only after a reply
    /// corresponding to the previous message has been received by the provider.
    /// If multiple level transitions occur during that time, the watcher will be
    /// notified of the latest pressure level.
    ///
    /// 2. The level changes are edge-triggered, and clients are expected to maintain
    /// local state to track the current pressure level, if required. For example,
    /// a job might be notified of a CRITICAL level and drop all its caches as a result.
    /// Some time after this, it might want to trigger an activity that causes a
    /// fair amount of memory to be allocated. At this point, the job is expected to
    /// remember that the last pressure level it saw was CRITICAL, and refrain from
    /// triggering the memory-intensive activity.
    ///
    /// 3. As a performance optimization, the provider may decide to skip sending
    /// messages for some pressure level changes. For example, when oscillating across
    /// the NORMAL / WARNING boundary, it might not be worth notifying clients of every
    /// single transition. The provider might rate-limit messages in this case.
    /// On a similar note, the provider may decide to send repeated messages at the
    /// same pressure level, particularly CRITICAL, to indicate that further action
    /// needs to be taken.
    pub fn r#on_level_changed(
        &self,
        mut level: Level,
    ) -> fidl::client::QueryResponseFut<(), fidl::encoding::DefaultFuchsiaResourceDialect> {
        WatcherProxyInterface::r#on_level_changed(self, level)
    }
}

impl WatcherProxyInterface for WatcherProxy {
    type OnLevelChangedResponseFut =
        fidl::client::QueryResponseFut<(), fidl::encoding::DefaultFuchsiaResourceDialect>;
    fn r#on_level_changed(&self, mut level: Level) -> Self::OnLevelChangedResponseFut {
        fn _decode(
            mut _buf: Result<<fidl::encoding::DefaultFuchsiaResourceDialect as fidl::encoding::ResourceDialect>::MessageBufEtc, fidl::Error>,
        ) -> Result<(), fidl::Error> {
            let _response = fidl::client::decode_transaction_body::<
                fidl::encoding::EmptyPayload,
                fidl::encoding::DefaultFuchsiaResourceDialect,
                0x55d559533407fed9,
            >(_buf?)?;
            Ok(_response)
        }
        self.client.send_query_and_decode::<WatcherOnLevelChangedRequest, ()>(
            (level,),
            0x55d559533407fed9,
            fidl::encoding::DynamicFlags::empty(),
            _decode,
        )
    }
}

pub struct WatcherEventStream {
    event_receiver: fidl::client::EventReceiver<fidl::encoding::DefaultFuchsiaResourceDialect>,
}

impl std::marker::Unpin for WatcherEventStream {}

impl futures::stream::FusedStream for WatcherEventStream {
    fn is_terminated(&self) -> bool {
        self.event_receiver.is_terminated()
    }
}

impl futures::Stream for WatcherEventStream {
    type Item = Result<WatcherEvent, fidl::Error>;

    fn poll_next(
        mut self: std::pin::Pin<&mut Self>,
        cx: &mut std::task::Context<'_>,
    ) -> std::task::Poll<Option<Self::Item>> {
        match futures::ready!(futures::stream::StreamExt::poll_next_unpin(
            &mut self.event_receiver,
            cx
        )?) {
            Some(buf) => std::task::Poll::Ready(Some(WatcherEvent::decode(buf))),
            None => std::task::Poll::Ready(None),
        }
    }
}

#[derive(Debug)]
pub enum WatcherEvent {}

impl WatcherEvent {
    /// Decodes a message buffer as a [`WatcherEvent`].
    fn decode(
        mut buf: <fidl::encoding::DefaultFuchsiaResourceDialect as fidl::encoding::ResourceDialect>::MessageBufEtc,
    ) -> Result<WatcherEvent, fidl::Error> {
        let (bytes, _handles) = buf.split_mut();
        let (tx_header, _body_bytes) = fidl::encoding::decode_transaction_header(bytes)?;
        debug_assert_eq!(tx_header.tx_id, 0);
        match tx_header.ordinal {
            _ => Err(fidl::Error::UnknownOrdinal {
                ordinal: tx_header.ordinal,
                protocol_name: <WatcherMarker as fidl::endpoints::ProtocolMarker>::DEBUG_NAME,
            }),
        }
    }
}

/// A Stream of incoming requests for fuchsia.memorypressure/Watcher.
pub struct WatcherRequestStream {
    inner: std::sync::Arc<fidl::ServeInner<fidl::encoding::DefaultFuchsiaResourceDialect>>,
    is_terminated: bool,
}

impl std::marker::Unpin for WatcherRequestStream {}

impl futures::stream::FusedStream for WatcherRequestStream {
    fn is_terminated(&self) -> bool {
        self.is_terminated
    }
}

impl fidl::endpoints::RequestStream for WatcherRequestStream {
    type Protocol = WatcherMarker;
    type ControlHandle = WatcherControlHandle;

    fn from_channel(channel: ::fidl::AsyncChannel) -> Self {
        Self { inner: std::sync::Arc::new(fidl::ServeInner::new(channel)), is_terminated: false }
    }

    fn control_handle(&self) -> Self::ControlHandle {
        WatcherControlHandle { inner: self.inner.clone() }
    }

    fn into_inner(
        self,
    ) -> (::std::sync::Arc<fidl::ServeInner<fidl::encoding::DefaultFuchsiaResourceDialect>>, bool)
    {
        (self.inner, self.is_terminated)
    }

    fn from_inner(
        inner: std::sync::Arc<fidl::ServeInner<fidl::encoding::DefaultFuchsiaResourceDialect>>,
        is_terminated: bool,
    ) -> Self {
        Self { inner, is_terminated }
    }
}

impl futures::Stream for WatcherRequestStream {
    type Item = Result<WatcherRequest, fidl::Error>;

    fn poll_next(
        mut self: std::pin::Pin<&mut Self>,
        cx: &mut std::task::Context<'_>,
    ) -> std::task::Poll<Option<Self::Item>> {
        let this = &mut *self;
        if this.inner.check_shutdown(cx) {
            this.is_terminated = true;
            return std::task::Poll::Ready(None);
        }
        if this.is_terminated {
            panic!("polled WatcherRequestStream after completion");
        }
        fidl::encoding::with_tls_decode_buf::<_, fidl::encoding::DefaultFuchsiaResourceDialect>(
            |bytes, handles| {
                match this.inner.channel().read_etc(cx, bytes, handles) {
                    std::task::Poll::Ready(Ok(())) => {}
                    std::task::Poll::Pending => return std::task::Poll::Pending,
                    std::task::Poll::Ready(Err(zx_status::Status::PEER_CLOSED)) => {
                        this.is_terminated = true;
                        return std::task::Poll::Ready(None);
                    }
                    std::task::Poll::Ready(Err(e)) => {
                        return std::task::Poll::Ready(Some(Err(fidl::Error::ServerRequestRead(
                            e.into(),
                        ))));
                    }
                }

                // A message has been received from the channel
                let (header, _body_bytes) = fidl::encoding::decode_transaction_header(bytes)?;

                std::task::Poll::Ready(Some(match header.ordinal {
                    0x55d559533407fed9 => {
                        header.validate_request_tx_id(fidl::MethodType::TwoWay)?;
                        let mut req = fidl::new_empty!(
                            WatcherOnLevelChangedRequest,
                            fidl::encoding::DefaultFuchsiaResourceDialect
                        );
                        fidl::encoding::Decoder::<fidl::encoding::DefaultFuchsiaResourceDialect>::decode_into::<WatcherOnLevelChangedRequest>(&header, _body_bytes, handles, &mut req)?;
                        let control_handle = WatcherControlHandle { inner: this.inner.clone() };
                        Ok(WatcherRequest::OnLevelChanged {
                            level: req.level,

                            responder: WatcherOnLevelChangedResponder {
                                control_handle: std::mem::ManuallyDrop::new(control_handle),
                                tx_id: header.tx_id,
                            },
                        })
                    }
                    _ => Err(fidl::Error::UnknownOrdinal {
                        ordinal: header.ordinal,
                        protocol_name:
                            <WatcherMarker as fidl::endpoints::ProtocolMarker>::DEBUG_NAME,
                    }),
                }))
            },
        )
    }
}

/// Watcher protocol
/// To be implemented by clients who wish to be notified on memory pressure level changes.
#[derive(Debug)]
pub enum WatcherRequest {
    /// Sent to the registered client when the memory pressure level changes.
    /// `level`: indicates the current memory pressure level.
    ///
    /// Will also be invoked on initial connection via `RegisterWatcher`, so that a newly
    /// registered client can discover the current memory pressure level.
    ///
    /// The watcher must immediately reply with a message to acknowledge that it has
    /// received the level change notification, and has initiated required actions as a
    /// result. It may then continue to reclaim memory asynchronously after sending
    /// the acknowledgement.
    ///
    /// Some helpful guidelines for clients:
    /// 1. The watcher will be notified of new pressure level changes only after a reply
    /// corresponding to the previous message has been received by the provider.
    /// If multiple level transitions occur during that time, the watcher will be
    /// notified of the latest pressure level.
    ///
    /// 2. The level changes are edge-triggered, and clients are expected to maintain
    /// local state to track the current pressure level, if required. For example,
    /// a job might be notified of a CRITICAL level and drop all its caches as a result.
    /// Some time after this, it might want to trigger an activity that causes a
    /// fair amount of memory to be allocated. At this point, the job is expected to
    /// remember that the last pressure level it saw was CRITICAL, and refrain from
    /// triggering the memory-intensive activity.
    ///
    /// 3. As a performance optimization, the provider may decide to skip sending
    /// messages for some pressure level changes. For example, when oscillating across
    /// the NORMAL / WARNING boundary, it might not be worth notifying clients of every
    /// single transition. The provider might rate-limit messages in this case.
    /// On a similar note, the provider may decide to send repeated messages at the
    /// same pressure level, particularly CRITICAL, to indicate that further action
    /// needs to be taken.
    OnLevelChanged { level: Level, responder: WatcherOnLevelChangedResponder },
}

impl WatcherRequest {
    #[allow(irrefutable_let_patterns)]
    pub fn into_on_level_changed(self) -> Option<(Level, WatcherOnLevelChangedResponder)> {
        if let WatcherRequest::OnLevelChanged { level, responder } = self {
            Some((level, responder))
        } else {
            None
        }
    }

    /// Name of the method defined in FIDL
    pub fn method_name(&self) -> &'static str {
        match *self {
            WatcherRequest::OnLevelChanged { .. } => "on_level_changed",
        }
    }
}

#[derive(Debug, Clone)]
pub struct WatcherControlHandle {
    inner: std::sync::Arc<fidl::ServeInner<fidl::encoding::DefaultFuchsiaResourceDialect>>,
}

impl fidl::endpoints::ControlHandle for WatcherControlHandle {
    fn shutdown(&self) {
        self.inner.shutdown()
    }

    fn shutdown_with_epitaph(&self, status: zx_status::Status) {
        self.inner.shutdown_with_epitaph(status)
    }

    fn is_closed(&self) -> bool {
        self.inner.channel().is_closed()
    }
    fn on_closed(&self) -> fidl::OnSignalsRef<'_> {
        self.inner.channel().on_closed()
    }

    #[cfg(target_os = "fuchsia")]
    fn signal_peer(
        &self,
        clear_mask: zx::Signals,
        set_mask: zx::Signals,
    ) -> Result<(), zx_status::Status> {
        use fidl::Peered;
        self.inner.channel().signal_peer(clear_mask, set_mask)
    }
}

impl WatcherControlHandle {}

#[must_use = "FIDL methods require a response to be sent"]
#[derive(Debug)]
pub struct WatcherOnLevelChangedResponder {
    control_handle: std::mem::ManuallyDrop<WatcherControlHandle>,
    tx_id: u32,
}

/// Set the the channel to be shutdown (see [`WatcherControlHandle::shutdown`])
/// if the responder is dropped without sending a response, so that the client
/// doesn't hang. To prevent this behavior, call `drop_without_shutdown`.
impl std::ops::Drop for WatcherOnLevelChangedResponder {
    fn drop(&mut self) {
        self.control_handle.shutdown();
        // Safety: drops once, never accessed again
        unsafe { std::mem::ManuallyDrop::drop(&mut self.control_handle) };
    }
}

impl fidl::endpoints::Responder for WatcherOnLevelChangedResponder {
    type ControlHandle = WatcherControlHandle;

    fn control_handle(&self) -> &WatcherControlHandle {
        &self.control_handle
    }

    fn drop_without_shutdown(mut self) {
        // Safety: drops once, never accessed again due to mem::forget
        unsafe { std::mem::ManuallyDrop::drop(&mut self.control_handle) };
        // Prevent Drop from running (which would shut down the channel)
        std::mem::forget(self);
    }
}

impl WatcherOnLevelChangedResponder {
    /// Sends a response to the FIDL transaction.
    ///
    /// Sets the channel to shutdown if an error occurs.
    pub fn send(self) -> Result<(), fidl::Error> {
        let _result = self.send_raw();
        if _result.is_err() {
            self.control_handle.shutdown();
        }
        self.drop_without_shutdown();
        _result
    }

    /// Similar to "send" but does not shutdown the channel if an error occurs.
    pub fn send_no_shutdown_on_err(self) -> Result<(), fidl::Error> {
        let _result = self.send_raw();
        self.drop_without_shutdown();
        _result
    }

    fn send_raw(&self) -> Result<(), fidl::Error> {
        self.control_handle.inner.send::<fidl::encoding::EmptyPayload>(
            (),
            self.tx_id,
            0x55d559533407fed9,
            fidl::encoding::DynamicFlags::empty(),
        )
    }
}

mod internal {
    use super::*;

    impl fidl::encoding::ResourceTypeMarker for ProviderRegisterWatcherRequest {
        type Borrowed<'a> = &'a mut Self;
        fn take_or_borrow<'a>(
            value: &'a mut <Self as fidl::encoding::TypeMarker>::Owned,
        ) -> Self::Borrowed<'a> {
            value
        }
    }

    unsafe impl fidl::encoding::TypeMarker for ProviderRegisterWatcherRequest {
        type Owned = Self;

        #[inline(always)]
        fn inline_align(_context: fidl::encoding::Context) -> usize {
            4
        }

        #[inline(always)]
        fn inline_size(_context: fidl::encoding::Context) -> usize {
            4
        }
    }

    unsafe impl
        fidl::encoding::Encode<
            ProviderRegisterWatcherRequest,
            fidl::encoding::DefaultFuchsiaResourceDialect,
        > for &mut ProviderRegisterWatcherRequest
    {
        #[inline]
        unsafe fn encode(
            self,
            encoder: &mut fidl::encoding::Encoder<
                '_,
                fidl::encoding::DefaultFuchsiaResourceDialect,
            >,
            offset: usize,
            _depth: fidl::encoding::Depth,
        ) -> fidl::Result<()> {
            encoder.debug_check_bounds::<ProviderRegisterWatcherRequest>(offset);
            // Delegate to tuple encoding.
            fidl::encoding::Encode::<ProviderRegisterWatcherRequest, fidl::encoding::DefaultFuchsiaResourceDialect>::encode(
                (
                    <fidl::encoding::Endpoint<fidl::endpoints::ClientEnd<WatcherMarker>> as fidl::encoding::ResourceTypeMarker>::take_or_borrow(&mut self.watcher),
                ),
                encoder, offset, _depth
            )
        }
    }
    unsafe impl<
        T0: fidl::encoding::Encode<
                fidl::encoding::Endpoint<fidl::endpoints::ClientEnd<WatcherMarker>>,
                fidl::encoding::DefaultFuchsiaResourceDialect,
            >,
    >
        fidl::encoding::Encode<
            ProviderRegisterWatcherRequest,
            fidl::encoding::DefaultFuchsiaResourceDialect,
        > for (T0,)
    {
        #[inline]
        unsafe fn encode(
            self,
            encoder: &mut fidl::encoding::Encoder<
                '_,
                fidl::encoding::DefaultFuchsiaResourceDialect,
            >,
            offset: usize,
            depth: fidl::encoding::Depth,
        ) -> fidl::Result<()> {
            encoder.debug_check_bounds::<ProviderRegisterWatcherRequest>(offset);
            // Zero out padding regions. There's no need to apply masks
            // because the unmasked parts will be overwritten by fields.
            // Write the fields.
            self.0.encode(encoder, offset + 0, depth)?;
            Ok(())
        }
    }

    impl fidl::encoding::Decode<Self, fidl::encoding::DefaultFuchsiaResourceDialect>
        for ProviderRegisterWatcherRequest
    {
        #[inline(always)]
        fn new_empty() -> Self {
            Self {
                watcher: fidl::new_empty!(
                    fidl::encoding::Endpoint<fidl::endpoints::ClientEnd<WatcherMarker>>,
                    fidl::encoding::DefaultFuchsiaResourceDialect
                ),
            }
        }

        #[inline]
        unsafe fn decode(
            &mut self,
            decoder: &mut fidl::encoding::Decoder<
                '_,
                fidl::encoding::DefaultFuchsiaResourceDialect,
            >,
            offset: usize,
            _depth: fidl::encoding::Depth,
        ) -> fidl::Result<()> {
            decoder.debug_check_bounds::<Self>(offset);
            // Verify that padding bytes are zero.
            fidl::decode!(
                fidl::encoding::Endpoint<fidl::endpoints::ClientEnd<WatcherMarker>>,
                fidl::encoding::DefaultFuchsiaResourceDialect,
                &mut self.watcher,
                decoder,
                offset + 0,
                _depth
            )?;
            Ok(())
        }
    }
}