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// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//! Execution contexts.
//!
//! This module defines "context" traits, which allow code in this crate to be
//! written agnostic to their execution context.
//!
//! All of the code in this crate operates in terms of "events". When an event
//! occurs (for example, a packet is received, an application makes a request,
//! or a timer fires), a function is called to handle that event. In response to
//! that event, the code may wish to emit new events (for example, to send a
//! packet, to respond to an application request, or to install a new timer).
//! The traits in this module provide the ability to emit new events. For
//! example, if, in order to handle some event, we need the ability to install
//! new timers, then the function to handle that event would take a
//! [`TimerContext`] parameter, which it could use to install new timers.
//!
//! Structuring code this way allows us to write code which is agnostic to
//! execution context - a test fake or any number of possible "real-world"
//! implementations of these traits all appear as indistinguishable, opaque
//! trait implementations to our code.
//!
//! The benefits are deeper than this, though. Large units of code can be
//! subdivided into smaller units that view each other as "contexts". For
//! example, the ARP implementation in the [`crate::device::arp`] module defines
//! the [`ArpContext`] trait, which is an execution context for ARP operations.
//! It is implemented both by the test fakes in that module, and also by the
//! Ethernet device implementation in the [`crate::device::ethernet`] module.
//!
//! This subdivision of code into small units in turn enables modularity. If,
//! for example, the IP code sees transport layer protocols as execution
//! contexts, then customizing which transport layer protocols are supported is
//! just a matter of providing a different implementation of the transport layer
//! context traits (this isn't what we do today, but we may in the future).
use core::{convert::Infallible as Never, ffi::CStr, fmt::Debug, time::Duration};
use lock_order::Unlocked;
use packet::{BufferMut, Serializer};
use rand::{CryptoRng, RngCore};
use crate::{
counters::Counter,
marker::{BindingsContext, BindingsTypes},
state::StackState,
sync, Instant,
};
pub use netstack3_base::{
ContextPair, CoreTimerContext, InstantBindingsTypes, InstantContext, NestedIntoCoreTimerCtx,
TimerBindingsTypes, TimerContext2,
};
/// A marker trait indicating that the implementor is not the [`FakeCoreCtx`]
/// type found in test environments.
///
/// See [this issue] for details on why this is needed.
///
/// [`FakeCoreCtx`]: testutil::FakeCoreCtx
/// [this issue]: https://github.com/rust-lang/rust/issues/97811
pub(crate) trait NonTestCtxMarker {}
impl<BC: BindingsContext, L> NonTestCtxMarker for CoreCtx<'_, BC, L> {}
/// An [`InstantContext`] which stores a cached value for the current time.
///
/// `CachedInstantCtx`s are constructed via [`new_cached_instant_context`].
pub(crate) struct CachedInstantCtx<I>(I);
impl<I: Instant + 'static> InstantBindingsTypes for CachedInstantCtx<I> {
type Instant = I;
}
impl<I: Instant + 'static> InstantContext for CachedInstantCtx<I> {
fn now(&self) -> I {
self.0.clone()
}
}
/// Construct a new `CachedInstantCtx` from the current time.
///
/// This is a hack until we figure out a strategy for splitting context objects.
/// Currently, since most context methods take a `&mut self` argument, lifetimes
/// which don't need to conflict in principle - such as the lifetime of state
/// obtained mutably from [`StateContext`] and the lifetime required to call the
/// [`InstantContext::now`] method on the same object - do conflict, and thus
/// cannot overlap. Until we figure out an approach to deal with that problem,
/// this exists as a workaround.
pub(crate) fn new_cached_instant_context<I: InstantContext + ?Sized>(
bindings_ctx: &I,
) -> CachedInstantCtx<I::Instant> {
CachedInstantCtx(bindings_ctx.now())
}
/// A context that supports scheduling timers.
pub trait TimerContext<Id>: InstantContext {
/// Schedule a timer to fire after some duration.
///
/// `schedule_timer` schedules the given timer to be fired after `duration`
/// has elapsed, overwriting any previous timer with the same ID.
///
/// If there was previously a timer with that ID, return the time at which
/// is was scheduled to fire.
///
/// # Panics
///
/// `schedule_timer` may panic if `duration` is large enough that
/// `self.now() + duration` overflows.
fn schedule_timer(&mut self, duration: Duration, id: Id) -> Option<Self::Instant> {
self.schedule_timer_instant(self.now().checked_add(duration).unwrap(), id)
}
/// Schedule a timer to fire at some point in the future.
///
/// `schedule_timer` schedules the given timer to be fired at `time`,
/// overwriting any previous timer with the same ID.
///
/// If there was previously a timer with that ID, return the time at which
/// is was scheduled to fire.
fn schedule_timer_instant(&mut self, time: Self::Instant, id: Id) -> Option<Self::Instant>;
/// Cancel a timer.
///
/// If a timer with the given ID exists, it is canceled and the instant at
/// which it was scheduled to fire is returned.
fn cancel_timer(&mut self, id: Id) -> Option<Self::Instant>;
/// Cancel all timers which satisfy a predicate.
///
/// `cancel_timers_with` calls `f` on each scheduled timer, and cancels any
/// timer for which `f` returns true.
fn cancel_timers_with<F: FnMut(&Id) -> bool>(&mut self, f: F);
/// Get the instant a timer will fire, if one is scheduled.
///
/// Returns the [`Instant`] a timer with ID `id` will be invoked. If no
/// timer with the given ID exists, `scheduled_instant` will return `None`.
fn scheduled_instant(&self, id: Id) -> Option<Self::Instant>;
}
/// A handler for timer firing events.
///
/// A `TimerHandler` is a type capable of handling the event of a timer firing.
pub trait TimerHandler<BC, Id> {
/// Handle a timer firing.
fn handle_timer(&mut self, bindings_ctx: &mut BC, id: Id);
}
// NOTE:
// - Code in this crate is required to only obtain random values through an
// `RngContext`. This allows a deterministic RNG to be provided when useful
// (for example, in tests).
// - The CSPRNG requirement exists so that random values produced within the
// network stack are not predictable by outside observers. This helps prevent
// certain kinds of fingerprinting and denial of service attacks.
/// A context that provides a random number generator (RNG).
pub trait RngContext {
// TODO(joshlf): If the CSPRNG requirement becomes a performance problem,
// introduce a second, non-cryptographically secure, RNG.
/// The random number generator (RNG) provided by this `RngContext`.
///
/// The provided RNG must be cryptographically secure, and users may rely on
/// that property for their correctness and security.
type Rng<'a>: RngCore + CryptoRng
where
Self: 'a;
/// Gets the random number generator (RNG).
fn rng(&mut self) -> Self::Rng<'_>;
}
/// A context for receiving frames.
pub trait RecvFrameContext<BC, Meta> {
/// Receive a frame.
///
/// `receive_frame` receives a frame with the given metadata.
fn receive_frame<B: BufferMut + Debug>(
&mut self,
bindings_ctx: &mut BC,
metadata: Meta,
frame: B,
);
}
/// Any type can implement a receive frame context with uninstantiable metadata.
impl<T, BC> RecvFrameContext<BC, Never> for T {
fn receive_frame<B: BufferMut>(&mut self, _bindings_ctx: &mut BC, metadata: Never, _frame: B) {
match metadata {}
}
}
/// A context for sending frames.
pub trait SendFrameContext<BC, Meta> {
// TODO(joshlf): Add an error type parameter or associated type once we need
// different kinds of errors.
/// Send a frame.
///
/// `send_frame` sends a frame with the given metadata. The frame itself is
/// passed as a [`Serializer`] which `send_frame` is responsible for
/// serializing. If serialization fails for any reason, the original,
/// unmodified `Serializer` is returned.
///
/// [`Serializer`]: packet::Serializer
fn send_frame<S>(&mut self, bindings_ctx: &mut BC, metadata: Meta, frame: S) -> Result<(), S>
where
S: Serializer,
S::Buffer: BufferMut;
}
/// A context that stores counters.
///
/// `CounterContext` exposes access to counters for observation and debugging.
pub trait CounterContext<T> {
/// Call the function with an immutable reference to counter type T.
fn with_counters<O, F: FnOnce(&T) -> O>(&self, cb: F) -> O;
/// Increments the counter returned by the callback.
fn increment<F: FnOnce(&T) -> &Counter>(&self, cb: F) {
self.with_counters(|counters| cb(counters).increment());
}
}
/// A context that provides access to per-resource counters for observation and
/// debugging.
pub trait ResourceCounterContext<R, T>: CounterContext<T> {
/// Call `cb` with an immutable reference to the set of counters on `resource`.
fn with_per_resource_counters<O, F: FnOnce(&T) -> O>(&mut self, resource: &R, cb: F) -> O;
/// Increments both the per-resource and stackwide versions of
/// the counter returned by the callback.
fn increment<F: Fn(&T) -> &Counter>(&mut self, resource: &R, cb: F) {
self.with_per_resource_counters(resource, |counters| cb(counters).increment());
self.with_counters(|counters| cb(counters).increment());
}
}
/// A context for emitting events.
///
/// `EventContext` encodes the common pattern for emitting atomic events of type
/// `T` from core. An implementation of `EventContext` must guarantee that
/// events are processed in the order they are emitted.
pub trait EventContext<T> {
/// Handles `event`.
fn on_event(&mut self, event: T);
}
/// A context for emitting tracing data.
pub trait TracingContext {
/// The scope of a trace duration.
///
/// Its lifetime corresponds to the beginning and end of the duration.
type DurationScope;
/// Writes a duration event which ends when the returned scope is dropped.
///
/// Durations describe work which is happening synchronously on one thread.
/// Care should be taken to avoid a duration's scope spanning an `await`
/// point in asynchronous code.
fn duration(&self, name: &'static CStr) -> Self::DurationScope;
}
/// A context trait determining the types to be used for reference notifications.
pub trait ReferenceNotifiers {
/// The receiver for shared reference destruction notifications.
type ReferenceReceiver<T: 'static>: 'static;
/// The notifier for shared reference destruction notifications.
type ReferenceNotifier<T: Send + 'static>: sync::RcNotifier<T> + 'static;
/// Creates a new Notifier/Receiver pair for `T`.
///
/// `debug_references` is given to provide information on outstanding
/// references that caused the notifier to be requested.
fn new_reference_notifier<T: Send + 'static, D: Debug>(
debug_references: D,
) -> (Self::ReferenceNotifier<T>, Self::ReferenceReceiver<T>);
}
/// Provides access to core context implementations.
///
/// `L` is the current lock level of `CoreCtx`. The alias [`UnlockedCoreCtx`] is
/// provided at the [`Unlocked`] level.
pub type CoreCtx<'a, BT, L> = Locked<&'a StackState<BT>, L>;
pub(crate) type CoreCtxAndResource<'a, BT, R, L> =
Locked<lock_order::OwnedTupleWrapper<&'a StackState<BT>, &'a R>, L>;
/// An alias for an unlocked [`CoreCtx`].
pub type UnlockedCoreCtx<'a, BT> = CoreCtx<'a, BT, Unlocked>;
pub(crate) use locked::Locked;
/// A type that provides a context implementation.
///
/// This trait allows for [`CtxPair`] to hold context implementations
/// agnostically of the storage method and how they're implemented. For example,
/// tests usually create API structs with a mutable borrow to contexts, while
/// the core context exposed to bindings is implemented on an owned [`CoreCtx`]
/// type.
///
/// The shape of this trait is equivalent to [`core::ops::DerefMut`] but we
/// decide against using that because of the automatic dereferencing semantics
/// the compiler provides around implementers of `DerefMut`.
pub trait ContextProvider {
/// The context provided by this `ContextProvider`.
type Context: Sized;
/// Gets a mutable borrow to this context.
fn context(&mut self) -> &mut Self::Context;
}
impl<'a, T: Sized> ContextProvider for &'a mut T {
type Context = T;
fn context(&mut self) -> &mut Self::Context {
&mut *self
}
}
impl<'a, BT, L> ContextProvider for CoreCtx<'a, BT, L>
where
BT: BindingsTypes,
{
type Context = Self;
fn context(&mut self) -> &mut Self::Context {
self
}
}
/// A concrete implementation of [`ContextPair`].
///
///
/// `CtxPair` provides a [`ContextPair`] implementation when `CC` and `BC` are
/// [`ContextProvider`] and using their respective targets as the `CoreContext`
/// and `BindingsContext` associated types.
pub struct CtxPair<CC, BC> {
pub(crate) core_ctx: CC,
pub(crate) bindings_ctx: BC,
}
impl<CC, BC> ContextPair for CtxPair<CC, BC>
where
CC: ContextProvider,
BC: ContextProvider,
{
type CoreContext = CC::Context;
type BindingsContext = BC::Context;
fn contexts(&mut self) -> (&mut Self::CoreContext, &mut Self::BindingsContext) {
let Self { core_ctx, bindings_ctx } = self;
(core_ctx.context(), bindings_ctx.context())
}
}
/// Provides a crate-local wrapper for `[lock_order::Locked]`.
///
/// This module is intentionally private so usage is limited to the type alias
/// in [`CoreCtx`].
mod locked {
use super::{BindingsTypes, CoreCtx, StackState};
use core::ops::Deref;
use lock_order::{wrap::LockedWrapper, Locked as ExternalLocked, TupleWrapper, Unlocked};
/// A crate-local wrapper on [`lock_order::Locked`].
pub struct Locked<T, L>(ExternalLocked<T, L>);
impl<T, L> LockedWrapper<T, L> for Locked<T, L>
where
T: Deref,
T::Target: Sized,
{
type AtLockLevel<'l, M> = Locked<&'l T::Target, M>
where
M: 'l,
T: 'l;
type CastWrapper<X> = Locked<X, L>
where
X: Deref,
X::Target: Sized;
fn wrap<'l, M>(locked: ExternalLocked<&'l T::Target, M>) -> Self::AtLockLevel<'l, M>
where
M: 'l,
T: 'l,
{
Locked(locked)
}
fn wrap_cast<R: Deref>(locked: ExternalLocked<R, L>) -> Self::CastWrapper<R>
where
R::Target: Sized,
{
Locked(locked)
}
fn get_mut(&mut self) -> &mut ExternalLocked<T, L> {
let Self(locked) = self;
locked
}
fn get(&self) -> &ExternalLocked<T, L> {
let Self(locked) = self;
locked
}
}
impl<'a, BT: BindingsTypes> CoreCtx<'a, BT, Unlocked> {
/// Creates a new `CoreCtx` from a borrowed [`StackState`].
pub fn new(stack_state: &'a StackState<BT>) -> Self {
Self(ExternalLocked::new(stack_state))
}
}
impl<'a, BT, R, L, T> Locked<T, L>
where
R: 'a,
T: Deref<Target = TupleWrapper<&'a StackState<BT>, &'a R>>,
BT: BindingsTypes,
{
pub(crate) fn cast_resource(&mut self) -> Locked<&'_ R, L> {
let Self(locked) = self;
Locked(locked.cast_with(|c| c.right()))
}
pub(crate) fn cast_core_ctx(&mut self) -> CoreCtx<'_, BT, L> {
let Self(locked) = self;
crate::CoreCtx::<BT, L>::wrap(locked.cast_with(|c| c.left()))
}
}
}
/// Fake implementations of context traits.
///
/// Each trait `Xxx` has a fake called `FakeXxx`. `FakeXxx` implements `Xxx`,
/// and `impl<T> FakeXxx for T` where either `T: AsRef<FakeXxx>` or `T:
/// AsMut<FakeXxx>` or both (depending on the trait). This allows fake
/// implementations to be composed easily - any container type need only provide
/// the appropriate `AsRef` and/or `AsMut` implementations, and the blanket impl
/// will take care of the rest.
#[cfg(any(test, feature = "testutils"))]
pub(crate) mod testutil {
use alloc::{boxed::Box, collections::BinaryHeap, format, string::String, sync::Arc, vec::Vec};
#[cfg(test)]
use alloc::{collections::HashMap, vec};
use core::{convert::Infallible as Never, fmt::Debug, hash::Hash};
#[cfg(test)]
use core::{marker::PhantomData, ops};
#[cfg(test)]
use assert_matches::assert_matches;
use derivative::Derivative;
use net_types::ip::IpVersion;
#[cfg(test)]
use packet::Buf;
use rand_xorshift::XorShiftRng;
use super::*;
use crate::{
data_structures::ref_counted_hash_map::{RefCountedHashSet, RemoveResult},
device::{link::LinkDevice, pure_ip::PureIpWeakDeviceId, DeviceLayerTypes},
filter::FilterBindingsTypes,
ip::device::nud::{LinkResolutionContext, LinkResolutionNotifier},
sync::Mutex,
testutil::FakeCryptoRng,
};
#[cfg(test)]
use crate::{
device::{EthernetDeviceId, EthernetWeakDeviceId},
filter::FilterHandlerProvider,
testutil::DispatchedFrame,
};
pub use netstack3_base::testutil::{FakeInstant, FakeInstantCtx};
/// Arbitrary data of type `D` attached to a `FakeInstant`.
///
/// `InstantAndData` implements `Ord` and `Eq` to be used in a `BinaryHeap`
/// and ordered by `FakeInstant`.
#[derive(Clone, Debug)]
pub(crate) struct InstantAndData<D>(pub(crate) FakeInstant, pub(crate) D);
impl<D> InstantAndData<D> {
pub(crate) fn new(time: FakeInstant, data: D) -> Self {
Self(time, data)
}
}
impl<D> Eq for InstantAndData<D> {}
impl<D> PartialEq for InstantAndData<D> {
fn eq(&self, other: &Self) -> bool {
self.0 == other.0
}
}
impl<D> Ord for InstantAndData<D> {
fn cmp(&self, other: &Self) -> core::cmp::Ordering {
other.0.cmp(&self.0)
}
}
impl<D> PartialOrd for InstantAndData<D> {
fn partial_cmp(&self, other: &Self) -> Option<core::cmp::Ordering> {
Some(self.cmp(other))
}
}
/// A fake [`TimerContext`] which stores time as a [`FakeInstantCtx`].
pub(crate) struct FakeTimerCtx<Id> {
pub(crate) instant: FakeInstantCtx,
timers: BinaryHeap<InstantAndData<Id>>,
}
impl<Id> Default for FakeTimerCtx<Id> {
fn default() -> FakeTimerCtx<Id> {
FakeTimerCtx { instant: FakeInstantCtx::default(), timers: BinaryHeap::default() }
}
}
impl<Id> AsMut<FakeTimerCtx<Id>> for FakeTimerCtx<Id> {
fn as_mut(&mut self) -> &mut FakeTimerCtx<Id> {
self
}
}
impl<Id: Clone> FakeTimerCtx<Id> {
/// Get an ordered list of all currently-scheduled timers.
#[cfg(test)]
pub(crate) fn timers(&self) -> Vec<(FakeInstant, Id)> {
self.timers
.clone()
.into_sorted_vec()
.into_iter()
.map(|InstantAndData(i, id)| (i, id))
.collect()
}
}
#[cfg(test)]
impl<Id: Debug + Clone + Hash + Eq> FakeTimerCtx<Id> {
/// Asserts that `self` contains exactly the timers in `timers`.
///
/// # Panics
///
/// Panics if `timers` contains the same ID more than once or if `self`
/// does not contain exactly the timers in `timers`.
///
/// [`RangeBounds<FakeInstant>`]: core::ops::RangeBounds
#[track_caller]
pub(crate) fn assert_timers_installed<I: IntoIterator<Item = (Id, FakeInstant)>>(
&self,
timers: I,
) {
self.assert_timers_installed_range(
timers.into_iter().map(|(id, instant)| (id, instant..=instant)),
);
}
/// Like [`assert_timers_installed`] but receives a range instants to
/// match.
///
/// Each timer must be present, and its deadline must fall into the
/// specified range.
#[track_caller]
pub(crate) fn assert_timers_installed_range<
R: ops::RangeBounds<FakeInstant> + Debug,
I: IntoIterator<Item = (Id, R)>,
>(
&self,
timers: I,
) {
self.assert_timers_installed_inner(timers, true);
}
/// Asserts that `self` contains at least the timers in `timers`.
///
/// Like [`assert_timers_installed`], but only asserts that `timers` is
/// a subset of the timers installed; other timers may be installed in
/// addition to those in `timers`.
#[track_caller]
pub(crate) fn assert_some_timers_installed<I: IntoIterator<Item = (Id, FakeInstant)>>(
&self,
timers: I,
) {
self.assert_some_timers_installed_range(
timers.into_iter().map(|(id, instant)| (id, instant..=instant)),
);
}
/// Like [`assert_some_timers_installed`] but receives instant ranges
/// to match like [`assert_timers_installed_range`].
#[track_caller]
pub(crate) fn assert_some_timers_installed_range<
R: ops::RangeBounds<FakeInstant> + Debug,
I: IntoIterator<Item = (Id, R)>,
>(
&self,
timers: I,
) {
self.assert_timers_installed_inner(timers, false);
}
/// Asserts that no timers are installed.
///
/// # Panics
///
/// Panics if any timers are installed.
#[track_caller]
pub(crate) fn assert_no_timers_installed(&self) {
self.assert_timers_installed([]);
}
#[track_caller]
fn assert_timers_installed_inner<
R: ops::RangeBounds<FakeInstant> + Debug,
I: IntoIterator<Item = (Id, R)>,
>(
&self,
timers: I,
exact: bool,
) {
let mut timers = timers.into_iter().fold(HashMap::new(), |mut timers, (id, range)| {
assert_matches!(timers.insert(id, range), None);
timers
});
enum Error<Id, R: ops::RangeBounds<FakeInstant>> {
ExpectedButMissing { id: Id, range: R },
UnexpectedButPresent { id: Id, instant: FakeInstant },
UnexpectedInstant { id: Id, range: R, instant: FakeInstant },
}
let mut errors = Vec::new();
// Make sure that all installed timers were expected (present in
// `timers`).
for InstantAndData(instant, id) in self.timers.iter().cloned() {
match timers.remove(&id) {
None => {
if exact {
errors.push(Error::UnexpectedButPresent { id, instant })
}
}
Some(range) => {
if !range.contains(&instant) {
errors.push(Error::UnexpectedInstant { id, range, instant })
}
}
}
}
// Make sure that all expected timers were already found in
// `self.timers` (and removed from `timers`).
errors
.extend(timers.drain().map(|(id, range)| Error::ExpectedButMissing { id, range }));
if errors.len() > 0 {
let mut s = String::from("Unexpected timer contents:");
for err in errors {
s += &match err {
Error::ExpectedButMissing { id, range } => {
format!("\n\tMissing timer {:?} with deadline {:?}", id, range)
}
Error::UnexpectedButPresent { id, instant } => {
format!("\n\tUnexpected timer {:?} with deadline {:?}", id, instant)
}
Error::UnexpectedInstant { id, range, instant } => format!(
"\n\tTimer {:?} has unexpected deadline {:?} (wanted {:?})",
id, instant, range
),
};
}
panic!("{}", s);
}
}
}
impl<Id> AsRef<FakeInstantCtx> for FakeTimerCtx<Id> {
fn as_ref(&self) -> &FakeInstantCtx {
&self.instant
}
}
impl<Id: PartialEq> FakeTimerCtx<Id> {
// Just like `TimerContext::cancel_timer`, but takes a reference to `Id`
// rather than a value. This allows us to implement
// `schedule_timer_instant`, which needs to retain ownership of the
// `Id`.
fn cancel_timer_inner(&mut self, id: &Id) -> Option<FakeInstant> {
let mut r: Option<FakeInstant> = None;
// NOTE(brunodalbo): Cancelling timers can be made a faster than
// this if we keep two data structures and require that `Id: Hash`.
self.timers = self
.timers
.drain()
.filter(|t| {
if &t.1 == id {
r = Some(t.0);
false
} else {
true
}
})
.collect::<Vec<_>>()
.into();
r
}
}
// TODO(https://fxbug.dev/42083407): Improve the fake timer implementation
// to not rely on hashing the dispatch IDs. This implementation gives us a
// way to soft transition to the new world, but the new API is not asking
// for DispatchId uniqueness between timers, even though that's how current
// usage works.
impl<Id: Debug + Clone + Send + Sync> TimerBindingsTypes for FakeTimerCtx<Id> {
type Timer = Id;
type DispatchId = Id;
}
impl<Id: PartialEq + Debug + Clone + Send + Sync> TimerContext2 for FakeTimerCtx<Id> {
fn new_timer(&mut self, id: Self::DispatchId) -> Self::Timer {
id
}
fn schedule_timer_instant2(
&mut self,
time: Self::Instant,
timer: &mut Self::Timer,
) -> Option<Self::Instant> {
self.schedule_timer_instant(time, timer.clone())
}
fn cancel_timer2(&mut self, timer: &mut Self::Timer) -> Option<Self::Instant> {
self.cancel_timer(timer.clone())
}
fn scheduled_instant2(&self, timer: &mut Self::Timer) -> Option<Self::Instant> {
self.scheduled_instant(timer.clone())
}
}
impl<Id: PartialEq> TimerContext<Id> for FakeTimerCtx<Id> {
fn schedule_timer_instant(&mut self, time: FakeInstant, id: Id) -> Option<FakeInstant> {
let ret = self.cancel_timer_inner(&id);
self.timers.push(InstantAndData::new(time, id));
ret
}
fn cancel_timer(&mut self, id: Id) -> Option<FakeInstant> {
self.cancel_timer_inner(&id)
}
fn cancel_timers_with<F: FnMut(&Id) -> bool>(&mut self, mut f: F) {
self.timers = self.timers.drain().filter(|t| !f(&t.1)).collect::<Vec<_>>().into();
}
fn scheduled_instant(&self, id: Id) -> Option<FakeInstant> {
self.timers.iter().find_map(|x| if x.1 == id { Some(x.0) } else { None })
}
}
/// Adds methods for interacting with [`FakeTimerCtx`] and its wrappers.
pub trait FakeTimerCtxExt<Id>: Sized {
/// Triggers the next timer, if any, by using the provided `handler`.
///
/// `trigger_next_timer` triggers the next timer, if any, advances the
/// internal clock to the timer's scheduled time, and returns its ID.
fn trigger_next_timer<H: TimerHandler<Self, Id>>(&mut self, handler: &mut H) -> Option<Id>;
/// Skips the current time forward until `instant`, triggering all
/// timers until then, inclusive, by calling `f` on them.
///
/// Returns the timers which were triggered.
///
/// # Panics
///
/// Panics if `instant` is in the past.
fn trigger_timers_until_instant<H: TimerHandler<Self, Id>>(
&mut self,
instant: FakeInstant,
handler: &mut H,
) -> Vec<Id>;
/// Skips the current time forward by `duration`, triggering all timers
/// until then, inclusive, by passing them to the `handler`.
///
/// Returns the timers which were triggered.
fn trigger_timers_for<H: TimerHandler<Self, Id>>(
&mut self,
duration: Duration,
handler: &mut H,
) -> Vec<Id>;
/// Triggers timers and expects them to be the given timers.
///
/// The number of timers to be triggered is taken to be the number of
/// timers produced by `timers`. Timers may be triggered in any order.
///
/// # Panics
///
/// Panics under the following conditions:
/// - Fewer timers could be triggered than expected
/// - Timers were triggered that were not expected
/// - Timers that were expected were not triggered
#[track_caller]
fn trigger_timers_and_expect_unordered<
I: IntoIterator<Item = Id>,
H: TimerHandler<Self, Id>,
>(
&mut self,
timers: I,
handler: &mut H,
) where
Id: Debug + Hash + Eq;
/// Triggers timers until `instant` and expects them to be the given
/// timers.
///
/// Like `trigger_timers_and_expect_unordered`, except that timers will
/// only be triggered until `instant` (inclusive).
fn trigger_timers_until_and_expect_unordered<
I: IntoIterator<Item = Id>,
H: TimerHandler<Self, Id>,
>(
&mut self,
instant: FakeInstant,
timers: I,
handler: &mut H,
) where
Id: Debug + Hash + Eq;
/// Triggers timers for `duration` and expects them to be the given
/// timers.
///
/// Like `trigger_timers_and_expect_unordered`, except that timers will
/// only be triggered for `duration` (inclusive).
fn trigger_timers_for_and_expect<I: IntoIterator<Item = Id>, H: TimerHandler<Self, Id>>(
&mut self,
duration: Duration,
timers: I,
handler: &mut H,
) where
Id: Debug + Hash + Eq;
}
// TODO(https://fxbug.dev/42081080): hold lock on `FakeTimerCtx` across entire
// method to avoid potential race conditions.
impl<Id: Clone, Ctx: WithFakeTimerContext<Id>> FakeTimerCtxExt<Id> for Ctx {
/// Triggers the next timer, if any, by calling `f` on it.
///
/// `trigger_next_timer` triggers the next timer, if any, advances the
/// internal clock to the timer's scheduled time, and returns its ID.
fn trigger_next_timer<H: TimerHandler<Self, Id>>(&mut self, handler: &mut H) -> Option<Id> {
self.with_fake_timer_ctx_mut(|timers| {
timers.timers.pop().map(|InstantAndData(t, id)| {
timers.instant.time = t;
id
})
})
.map(|id| {
handler.handle_timer(self, id.clone());
id
})
}
/// Skips the current time forward until `instant`, triggering all
/// timers until then, inclusive, by giving them to `handler`.
///
/// Returns the timers which were triggered.
///
/// # Panics
///
/// Panics if `instant` is in the past.
fn trigger_timers_until_instant<H: TimerHandler<Self, Id>>(
&mut self,
instant: FakeInstant,
handler: &mut H,
) -> Vec<Id> {
assert!(instant >= self.with_fake_timer_ctx(|ctx| ctx.now()));
let mut timers = Vec::new();
while self.with_fake_timer_ctx_mut(|ctx| {
ctx.timers.peek().map(|InstantAndData(i, _id)| i <= &instant).unwrap_or(false)
}) {
timers.push(self.trigger_next_timer(handler).unwrap())
}
self.with_fake_timer_ctx_mut(|ctx| {
assert!(ctx.now() <= instant);
ctx.instant.time = instant;
});
timers
}
/// Skips the current time forward by `duration`, triggering all timers
/// until then, inclusive, by calling `f` on them.
///
/// Returns the timers which were triggered.
fn trigger_timers_for<H: TimerHandler<Self, Id>>(
&mut self,
duration: Duration,
handler: &mut H,
) -> Vec<Id> {
let instant = self.with_fake_timer_ctx(|ctx| ctx.now().saturating_add(duration));
// We know the call to `self.trigger_timers_until_instant` will not
// panic because we provide an instant that is greater than or equal
// to the current time.
self.trigger_timers_until_instant(instant, handler)
}
/// Triggers timers and expects them to be the given timers.
///
/// The number of timers to be triggered is taken to be the number of
/// timers produced by `timers`. Timers may be triggered in any order.
///
/// # Panics
///
/// Panics under the following conditions:
/// - Fewer timers could be triggered than expected
/// - Timers were triggered that were not expected
/// - Timers that were expected were not triggered
#[track_caller]
fn trigger_timers_and_expect_unordered<
I: IntoIterator<Item = Id>,
H: TimerHandler<Self, Id>,
>(
&mut self,
timers: I,
handler: &mut H,
) where
Id: Debug + Hash + Eq,
{
let mut timers = RefCountedHashSet::from_iter(timers);
for _ in 0..timers.len() {
let id = self.trigger_next_timer(handler).expect("ran out of timers to trigger");
match timers.remove(id.clone()) {
RemoveResult::Removed(()) | RemoveResult::StillPresent => {}
RemoveResult::NotPresent => panic!("triggered unexpected timer: {:?}", id),
}
}
if timers.len() > 0 {
let mut s = String::from("Expected timers did not trigger:");
for (id, count) in timers.iter_counts() {
s += &format!("\n\t{count}x {id:?}");
}
panic!("{}", s);
}
}
/// Triggers timers until `instant` and expects them to be the given
/// timers.
///
/// Like `trigger_timers_and_expect_unordered`, except that timers will
/// only be triggered until `instant` (inclusive).
fn trigger_timers_until_and_expect_unordered<
I: IntoIterator<Item = Id>,
H: TimerHandler<Self, Id>,
>(
&mut self,
instant: FakeInstant,
timers: I,
handler: &mut H,
) where
Id: Debug + Hash + Eq,
{
let mut timers = RefCountedHashSet::from_iter(timers);
let triggered_timers = self.trigger_timers_until_instant(instant, handler);
for id in triggered_timers {
match timers.remove(id.clone()) {
RemoveResult::Removed(()) | RemoveResult::StillPresent => {}
RemoveResult::NotPresent => panic!("triggered unexpected timer: {:?}", id),
}
}
if timers.len() > 0 {
let mut s = String::from("Expected timers did not trigger:");
for (id, count) in timers.iter_counts() {
s += &format!("\n\t{count}x {id:?}");
}
panic!("{}", s);
}
}
/// Triggers timers for `duration` and expects them to be the given
/// timers.
///
/// Like `trigger_timers_and_expect_unordered`, except that timers will
/// only be triggered for `duration` (inclusive).
fn trigger_timers_for_and_expect<I: IntoIterator<Item = Id>, H: TimerHandler<Self, Id>>(
&mut self,
duration: Duration,
timers: I,
handler: &mut H,
) where
Id: Debug + Hash + Eq,
{
let instant = self.with_fake_timer_ctx(|ctx| ctx.now().saturating_add(duration));
self.trigger_timers_until_and_expect_unordered(instant, timers, handler);
}
}
/// A fake [`FrameContext`].
pub struct FakeFrameCtx<Meta> {
frames: Vec<(Meta, Vec<u8>)>,
should_error_for_frame: Option<Box<dyn Fn(&Meta) -> bool + Send>>,
}
#[cfg(test)]
impl<Meta> FakeFrameCtx<Meta> {
/// Closure which can decide to cause an error to be thrown when
/// handling a frame, based on the metadata.
pub(crate) fn set_should_error_for_frame<F: Fn(&Meta) -> bool + Send + 'static>(
&mut self,
f: F,
) {
self.should_error_for_frame = Some(Box::new(f));
}
}
impl<Meta> Default for FakeFrameCtx<Meta> {
fn default() -> FakeFrameCtx<Meta> {
FakeFrameCtx { frames: Vec::new(), should_error_for_frame: None }
}
}
impl<Meta> FakeFrameCtx<Meta> {
/// Take all frames sent so far.
pub(crate) fn take_frames(&mut self) -> Vec<(Meta, Vec<u8>)> {
core::mem::take(&mut self.frames)
}
/// Get the frames sent so far.
#[cfg(test)]
pub(crate) fn frames(&self) -> &[(Meta, Vec<u8>)] {
self.frames.as_slice()
}
pub(crate) fn push(&mut self, meta: Meta, frame: Vec<u8>) {
self.frames.push((meta, frame))
}
}
impl<C, Meta> SendFrameContext<C, Meta> for FakeFrameCtx<Meta> {
fn send_frame<S>(
&mut self,
_bindings_ctx: &mut C,
metadata: Meta,
frame: S,
) -> Result<(), S>
where
S: Serializer,
S::Buffer: BufferMut,
{
if let Some(should_error_for_frame) = &self.should_error_for_frame {
if should_error_for_frame(&metadata) {
return Err(frame);
}
}
let buffer = frame.serialize_vec_outer().map_err(|(_err, s)| s)?;
self.push(metadata, buffer.as_ref().to_vec());
Ok(())
}
}
/// A fake [`EventContext`].
pub struct FakeEventCtx<E: Debug> {
events: Vec<E>,
must_watch_all_events: bool,
}
impl<E: Debug> EventContext<E> for FakeEventCtx<E> {
fn on_event(&mut self, event: E) {
self.events.push(event)
}
}
impl<E: Debug> Drop for FakeEventCtx<E> {
fn drop(&mut self) {
if self.must_watch_all_events {
assert!(
self.events.is_empty(),
"dropped context with unacknowledged events: {:?}",
self.events
);
}
}
}
impl<E: Debug> Default for FakeEventCtx<E> {
fn default() -> Self {
Self { events: Default::default(), must_watch_all_events: false }
}
}
impl<E: Debug> FakeEventCtx<E> {
#[cfg(test)]
pub(crate) fn take(&mut self) -> Vec<E> {
// Any client that calls `take()` is opting into watching events
// and must watch them all.
self.must_watch_all_events = true;
core::mem::take(&mut self.events)
}
}
/// A fake [`TracingContext`].
#[derive(Default)]
pub struct FakeTracingCtx;
impl TracingContext for FakeTracingCtx {
type DurationScope = ();
fn duration(&self, _: &'static CStr) {}
}
/// A tuple of device ID and IP version.
#[derive(Derivative)]
#[derivative(Debug(bound = ""))]
pub struct PureIpDeviceAndIpVersion<BT: DeviceLayerTypes> {
pub(crate) device: PureIpWeakDeviceId<BT>,
pub(crate) version: IpVersion,
}
/// A test helper used to provide an implementation of a bindings context.
pub(crate) struct FakeBindingsCtx<TimerId, Event: Debug, State, FrameMeta> {
pub(crate) rng: FakeCryptoRng<XorShiftRng>,
pub(crate) timers: FakeTimerCtx<TimerId>,
pub(crate) events: FakeEventCtx<Event>,
pub(crate) frames: FakeFrameCtx<FrameMeta>,
state: State,
}
impl<TimerId, Event: Debug, State, FrameMeta> ContextProvider
for FakeBindingsCtx<TimerId, Event, State, FrameMeta>
{
type Context = Self;
fn context(&mut self) -> &mut Self::Context {
self
}
}
impl<TimerId, Event: Debug, State: Default, FrameMeta> Default
for FakeBindingsCtx<TimerId, Event, State, FrameMeta>
{
fn default() -> Self {
Self {
rng: FakeCryptoRng::new_xorshift(0),
timers: FakeTimerCtx::default(),
events: FakeEventCtx::default(),
frames: FakeFrameCtx::default(),
state: Default::default(),
}
}
}
impl<TimerId, Event: Debug, State, FrameMeta> FakeBindingsCtx<TimerId, Event, State, FrameMeta> {
/// Seed the testing RNG with a specific value.
#[cfg(test)]
pub(crate) fn seed_rng(&mut self, seed: u128) {
self.rng = FakeCryptoRng::new_xorshift(seed);
}
/// Move the clock forward by the given duration without firing any
/// timers.
///
/// If any timers are scheduled to fire in the given duration, future
/// use of this `FakeCoreCtx` may have surprising or buggy behavior.
#[cfg(test)]
pub(crate) fn sleep_skip_timers(&mut self, duration: Duration) {
self.timers.instant.sleep(duration);
}
#[cfg(test)]
pub(crate) fn timer_ctx(&self) -> &FakeTimerCtx<TimerId> {
&self.timers
}
#[cfg(test)]
pub(crate) fn timer_ctx_mut(&mut self) -> &mut FakeTimerCtx<TimerId> {
&mut self.timers
}
#[cfg(test)]
pub(crate) fn take_events(&mut self) -> Vec<Event> {
self.events.take()
}
pub(crate) fn frame_ctx_mut(&mut self) -> &mut FakeFrameCtx<FrameMeta> {
&mut self.frames
}
pub(crate) fn state(&self) -> &State {
&self.state
}
pub(crate) fn state_mut(&mut self) -> &mut State {
&mut self.state
}
}
impl<TimerId, Event: Debug, State, FrameMeta> FilterBindingsTypes
for FakeBindingsCtx<TimerId, Event, State, FrameMeta>
{
type DeviceClass = ();
}
impl<TimerId, Event: Debug, State, FrameMeta> RngContext
for FakeBindingsCtx<TimerId, Event, State, FrameMeta>
{
type Rng<'a> = FakeCryptoRng<XorShiftRng> where Self: 'a;
fn rng(&mut self) -> Self::Rng<'_> {
self.rng.clone()
}
}
impl<Id, Event: Debug, State, FrameMeta> AsRef<FakeInstantCtx>
for FakeBindingsCtx<Id, Event, State, FrameMeta>
{
fn as_ref(&self) -> &FakeInstantCtx {
self.timers.as_ref()
}
}
impl<Id, Event: Debug, State, FrameMeta> AsRef<FakeTimerCtx<Id>>
for FakeBindingsCtx<Id, Event, State, FrameMeta>
{
fn as_ref(&self) -> &FakeTimerCtx<Id> {
&self.timers
}
}
impl<Id, Event: Debug, State, FrameMeta> AsMut<FakeTimerCtx<Id>>
for FakeBindingsCtx<Id, Event, State, FrameMeta>
{
fn as_mut(&mut self) -> &mut FakeTimerCtx<Id> {
&mut self.timers
}
}
impl<Id: Debug + PartialEq + Clone + Send + Sync, Event: Debug, State, FrameMeta>
TimerBindingsTypes for FakeBindingsCtx<Id, Event, State, FrameMeta>
{
type Timer = <FakeTimerCtx<Id> as TimerBindingsTypes>::Timer;
type DispatchId = <FakeTimerCtx<Id> as TimerBindingsTypes>::DispatchId;
}
impl<Id: Debug + PartialEq + Clone + Send + Sync, Event: Debug, State, FrameMeta> TimerContext2
for FakeBindingsCtx<Id, Event, State, FrameMeta>
{
fn new_timer(&mut self, id: Self::DispatchId) -> Self::Timer {
self.timers.new_timer(id)
}
fn schedule_timer_instant2(
&mut self,
time: Self::Instant,
timer: &mut Self::Timer,
) -> Option<Self::Instant> {
self.timers.schedule_timer_instant2(time, timer)
}
fn cancel_timer2(&mut self, timer: &mut Self::Timer) -> Option<Self::Instant> {
self.timers.cancel_timer2(timer)
}
fn scheduled_instant2(&self, timer: &mut Self::Timer) -> Option<Self::Instant> {
self.timers.scheduled_instant2(timer)
}
}
impl<Id: Debug + PartialEq, Event: Debug, State, FrameMeta> TimerContext<Id>
for FakeBindingsCtx<Id, Event, State, FrameMeta>
{
fn schedule_timer_instant(&mut self, time: FakeInstant, id: Id) -> Option<FakeInstant> {
self.timers.schedule_timer_instant(time, id)
}
fn cancel_timer(&mut self, id: Id) -> Option<FakeInstant> {
self.timers.cancel_timer(id)
}
fn cancel_timers_with<F: FnMut(&Id) -> bool>(&mut self, f: F) {
self.timers.cancel_timers_with(f);
}
fn scheduled_instant(&self, id: Id) -> Option<FakeInstant> {
self.timers.scheduled_instant(id)
}
}
impl<Id, Event: Debug, State, FrameMeta> EventContext<Event>
for FakeBindingsCtx<Id, Event, State, FrameMeta>
{
fn on_event(&mut self, event: Event) {
self.events.on_event(event)
}
}
impl<Id, Event: Debug, State, FrameMeta> TracingContext
for FakeBindingsCtx<Id, Event, State, FrameMeta>
{
type DurationScope = ();
fn duration(&self, _: &'static CStr) {}
}
impl<D: LinkDevice, Id, Event: Debug, State, FrameMeta> LinkResolutionContext<D>
for FakeBindingsCtx<Id, Event, State, FrameMeta>
{
type Notifier = FakeLinkResolutionNotifier<D>;
}
impl<Id, Event: Debug, State, FrameMeta> crate::ReferenceNotifiers
for FakeBindingsCtx<Id, Event, State, FrameMeta>
{
type ReferenceReceiver<T: 'static> = Never;
type ReferenceNotifier<T: Send + 'static> = Never;
fn new_reference_notifier<T: Send + 'static, D: Debug>(
debug_references: D,
) -> (Self::ReferenceNotifier<T>, Self::ReferenceReceiver<T>) {
// NB: We don't want deferred destruction in core tests. These are
// always single-threaded and single-task, and we want to encourage
// explicit cleanup.
panic!(
"FakeBindingsCtx can't create deferred reference notifiers for type {}: \
debug_references={debug_references:?}",
core::any::type_name::<T>()
);
}
}
#[derive(Debug)]
pub(crate) struct FakeLinkResolutionNotifier<D: LinkDevice>(
Arc<Mutex<Option<Result<D::Address, crate::error::AddressResolutionFailed>>>>,
);
impl<D: LinkDevice> LinkResolutionNotifier<D> for FakeLinkResolutionNotifier<D> {
type Observer =
Arc<Mutex<Option<Result<D::Address, crate::error::AddressResolutionFailed>>>>;
fn new() -> (Self, Self::Observer) {
let inner = Arc::new(Mutex::new(None));
(Self(inner.clone()), inner)
}
fn notify(self, result: Result<D::Address, crate::error::AddressResolutionFailed>) {
let Self(inner) = self;
let mut inner = inner.lock();
assert_eq!(*inner, None, "resolved link address was set more than once");
*inner = Some(result);
}
}
pub(crate) trait WithFakeTimerContext<TimerId> {
fn with_fake_timer_ctx<O, F: FnOnce(&FakeTimerCtx<TimerId>) -> O>(&self, f: F) -> O;
fn with_fake_timer_ctx_mut<O, F: FnOnce(&mut FakeTimerCtx<TimerId>) -> O>(
&mut self,
f: F,
) -> O;
}
#[cfg(test)]
pub(crate) trait WithFakeFrameContext<SendMeta> {
fn with_fake_frame_ctx_mut<O, F: FnOnce(&mut FakeFrameCtx<SendMeta>) -> O>(
&mut self,
f: F,
) -> O;
}
#[cfg(test)]
impl<CC, TimerId, Event: Debug, State> WithFakeTimerContext<TimerId>
for FakeCtxWithCoreCtx<CC, TimerId, Event, State>
{
fn with_fake_timer_ctx<O, F: FnOnce(&FakeTimerCtx<TimerId>) -> O>(&self, f: F) -> O {
let Self { core_ctx: _, bindings_ctx } = self;
f(&bindings_ctx.timers)
}
fn with_fake_timer_ctx_mut<O, F: FnOnce(&mut FakeTimerCtx<TimerId>) -> O>(
&mut self,
f: F,
) -> O {
let Self { core_ctx: _, bindings_ctx } = self;
f(&mut bindings_ctx.timers)
}
}
#[cfg(test)]
impl<TimerId, Event: Debug, State, FrameMeta> WithFakeTimerContext<TimerId>
for FakeBindingsCtx<TimerId, Event, State, FrameMeta>
{
fn with_fake_timer_ctx<O, F: FnOnce(&FakeTimerCtx<TimerId>) -> O>(&self, f: F) -> O {
f(&self.timers)
}
fn with_fake_timer_ctx_mut<O, F: FnOnce(&mut FakeTimerCtx<TimerId>) -> O>(
&mut self,
f: F,
) -> O {
f(&mut self.timers)
}
}
#[cfg(test)]
pub(crate) type FakeCtxWithCoreCtx<CC, TimerId, Event, BindingsCtxState> =
crate::testutil::ContextPair<CC, FakeBindingsCtx<TimerId, Event, BindingsCtxState, ()>>;
#[cfg(test)]
pub(crate) type FakeCtx<S, TimerId, Meta, Event, DeviceId, BindingsCtxState> =
FakeCtxWithCoreCtx<FakeCoreCtx<S, Meta, DeviceId>, TimerId, Event, BindingsCtxState>;
#[cfg(test)]
impl<CC, Id, Event: Debug, BindingsCtxState> AsRef<FakeInstantCtx>
for FakeCtxWithCoreCtx<CC, Id, Event, BindingsCtxState>
{
fn as_ref(&self) -> &FakeInstantCtx {
self.bindings_ctx.timers.as_ref()
}
}
#[cfg(test)]
impl<CC, Id, Event: Debug, BindingsCtxState> AsRef<FakeTimerCtx<Id>>
for FakeCtxWithCoreCtx<CC, Id, Event, BindingsCtxState>
{
fn as_ref(&self) -> &FakeTimerCtx<Id> {
&self.bindings_ctx.timers
}
}
#[cfg(test)]
impl<CC, Id, Event: Debug, BindingsCtxState> AsMut<FakeTimerCtx<Id>>
for FakeCtxWithCoreCtx<CC, Id, Event, BindingsCtxState>
{
fn as_mut(&mut self) -> &mut FakeTimerCtx<Id> {
&mut self.bindings_ctx.timers
}
}
#[cfg(test)]
impl<S, Id, Meta, Event: Debug, DeviceId, BindingsCtxState> AsMut<FakeFrameCtx<Meta>>
for FakeCtx<S, Id, Meta, Event, DeviceId, BindingsCtxState>
{
fn as_mut(&mut self) -> &mut FakeFrameCtx<Meta> {
&mut self.core_ctx.frames
}
}
#[cfg(test)]
impl<S, Id, Meta, Event: Debug, DeviceId, BindingsCtxState> WithFakeFrameContext<Meta>
for FakeCtx<S, Id, Meta, Event, DeviceId, BindingsCtxState>
{
fn with_fake_frame_ctx_mut<O, F: FnOnce(&mut FakeFrameCtx<Meta>) -> O>(
&mut self,
f: F,
) -> O {
f(&mut self.core_ctx.frames)
}
}
#[cfg(test)]
#[derive(Default)]
pub(crate) struct Wrapped<Outer, Inner> {
pub(crate) inner: Inner,
pub(crate) outer: Outer,
}
#[cfg(test)]
impl<Outer, Inner> ContextProvider for Wrapped<Outer, Inner> {
type Context = Self;
fn context(&mut self) -> &mut Self::Context {
self
}
}
#[cfg(test)]
pub(crate) type WrappedFakeCoreCtx<Outer, S, Meta, DeviceId> =
Wrapped<Outer, FakeCoreCtx<S, Meta, DeviceId>>;
#[cfg(test)]
impl<Outer, S, Meta, DeviceId> WrappedFakeCoreCtx<Outer, S, Meta, DeviceId> {
pub(crate) fn with_inner_and_outer_state(inner: S, outer: Outer) -> Self {
Self { inner: FakeCoreCtx::with_state(inner), outer }
}
}
#[cfg(test)]
impl<Outer, T, Inner: AsRef<T>> AsRef<T> for Wrapped<Outer, Inner> {
fn as_ref(&self) -> &T {
self.inner.as_ref()
}
}
#[cfg(test)]
impl<Outer, T, Inner: AsMut<T>> AsMut<T> for Wrapped<Outer, Inner> {
fn as_mut(&mut self) -> &mut T {
self.inner.as_mut()
}
}
/// A test helper used to provide an implementation of a core context.
#[cfg(test)]
#[derive(Derivative)]
#[derivative(Default(bound = "S: Default"))]
pub(crate) struct FakeCoreCtx<S, Meta, DeviceId> {
pub(crate) state: S,
pub(crate) frames: FakeFrameCtx<Meta>,
_devices_marker: PhantomData<DeviceId>,
}
#[cfg(test)]
impl<S, Meta, DeviceId> ContextProvider for FakeCoreCtx<S, Meta, DeviceId> {
type Context = Self;
fn context(&mut self) -> &mut Self::Context {
self
}
}
#[cfg(test)]
impl<S, Meta, DeviceId> AsRef<FakeCoreCtx<S, Meta, DeviceId>> for FakeCoreCtx<S, Meta, DeviceId> {
fn as_ref(&self) -> &FakeCoreCtx<S, Meta, DeviceId> {
self
}
}
#[cfg(test)]
impl<S, Meta, DeviceId> AsMut<FakeCoreCtx<S, Meta, DeviceId>> for FakeCoreCtx<S, Meta, DeviceId> {
fn as_mut(&mut self) -> &mut FakeCoreCtx<S, Meta, DeviceId> {
self
}
}
#[cfg(test)]
impl<I: packet_formats::ip::IpExt, BC: FilterBindingsTypes, S, Meta, DeviceId>
FilterHandlerProvider<I, BC> for FakeCoreCtx<S, Meta, DeviceId>
{
type Handler<'a> = crate::filter::NoopImpl where Self: 'a;
fn filter_handler(&mut self) -> Self::Handler<'_> {
crate::filter::NoopImpl
}
}
#[cfg(test)]
impl<Outer, I: packet_formats::ip::IpExt, BC: FilterBindingsTypes, S, Meta, DeviceId>
FilterHandlerProvider<I, BC> for Wrapped<Outer, FakeCoreCtx<S, Meta, DeviceId>>
{
type Handler<'a> = crate::filter::NoopImpl where Self: 'a;
fn filter_handler(&mut self) -> Self::Handler<'_> {
crate::filter::NoopImpl
}
}
#[cfg(test)]
impl<BC, S, Meta, DeviceId> CounterContext<BC> for FakeCoreCtx<S, Meta, DeviceId>
where
S: CounterContext<BC>,
{
fn with_counters<O, F: FnOnce(&BC) -> O>(&self, cb: F) -> O {
CounterContext::<BC>::with_counters(&self.state, cb)
}
}
#[cfg(test)]
impl<S, Meta, DeviceId> FakeCoreCtx<S, Meta, DeviceId> {
/// Constructs a `FakeCoreCtx` with the given state and default
/// `FakeTimerCtx`, and `FakeFrameCtx`.
pub(crate) fn with_state(state: S) -> Self {
FakeCoreCtx { state, frames: FakeFrameCtx::default(), _devices_marker: PhantomData }
}
/// Get an immutable reference to the inner state.
///
/// This method is provided instead of an [`AsRef`] impl to avoid
/// conflicting with user-provided implementations of `AsRef<T> for
/// FakeCtx<S, Id, Meta, Event>` for other types, `T`. It is named
/// `get_ref` instead of `as_ref` so that programmer doesn't need to
/// specify which `as_ref` method is intended.
pub(crate) fn get_ref(&self) -> &S {
&self.state
}
/// Get a mutable reference to the inner state.
///
/// `get_mut` is like `get_ref`, but it returns a mutable reference.
pub(crate) fn get_mut(&mut self) -> &mut S {
&mut self.state
}
/// Get the list of frames sent so far.
pub(crate) fn frames(&self) -> &[(Meta, Vec<u8>)] {
self.frames.frames()
}
/// Take the list of frames sent so far.
pub(crate) fn take_frames(&mut self) -> Vec<(Meta, Vec<u8>)> {
self.frames.take_frames()
}
/// Consumes the `FakeCoreCtx` and returns the inner state.
pub(crate) fn into_state(self) -> S {
self.state
}
}
#[cfg(test)]
impl<S, Meta, DeviceId> AsMut<FakeFrameCtx<Meta>> for FakeCoreCtx<S, Meta, DeviceId> {
fn as_mut(&mut self) -> &mut FakeFrameCtx<Meta> {
&mut self.frames
}
}
#[cfg(test)]
impl<S, Meta, DeviceId> WithFakeFrameContext<Meta> for FakeCoreCtx<S, Meta, DeviceId> {
fn with_fake_frame_ctx_mut<O, F: FnOnce(&mut FakeFrameCtx<Meta>) -> O>(
&mut self,
f: F,
) -> O {
f(&mut self.frames)
}
}
#[cfg(test)]
impl<Outer, Inner: WithFakeFrameContext<Meta>, Meta> WithFakeFrameContext<Meta>
for Wrapped<Outer, Inner>
{
fn with_fake_frame_ctx_mut<O, F: FnOnce(&mut FakeFrameCtx<Meta>) -> O>(
&mut self,
f: F,
) -> O {
self.inner.with_fake_frame_ctx_mut(f)
}
}
#[cfg(test)]
impl<S, Id, Meta, Event: Debug, DeviceId, BindingsCtxState, FrameMeta>
SendFrameContext<FakeBindingsCtx<Id, Event, BindingsCtxState, FrameMeta>, Meta>
for FakeCoreCtx<S, Meta, DeviceId>
{
fn send_frame<SS>(
&mut self,
bindings_ctx: &mut FakeBindingsCtx<Id, Event, BindingsCtxState, FrameMeta>,
metadata: Meta,
frame: SS,
) -> Result<(), SS>
where
SS: Serializer,
SS::Buffer: BufferMut,
{
self.frames.send_frame(bindings_ctx, metadata, frame)
}
}
#[cfg(test)]
#[derive(Debug)]
pub(crate) struct PendingFrameData<CtxId, Meta> {
pub(crate) dst_context: CtxId,
pub(crate) meta: Meta,
pub(crate) frame: Vec<u8>,
}
#[cfg(test)]
pub(crate) type PendingFrame<CtxId, Meta> = InstantAndData<PendingFrameData<CtxId, Meta>>;
/// A fake network, composed of many `FakeCoreCtx`s.
///
/// Provides a utility to have many contexts keyed by `CtxId` that can
/// exchange frames.
#[cfg(test)]
pub(crate) struct FakeNetwork<CtxId, Ctx: FakeNetworkContext, Links>
where
Links: FakeNetworkLinks<Ctx::SendMeta, Ctx::RecvMeta, CtxId>,
{
links: Links,
current_time: FakeInstant,
pending_frames: BinaryHeap<PendingFrame<CtxId, Ctx::RecvMeta>>,
// Declare `contexts` last to ensure that it is dropped last. See
// https://doc.rust-lang.org/std/ops/trait.Drop.html#drop-order for
// details.
contexts: HashMap<CtxId, Ctx>,
}
/// A context which can be used with a [`FakeNetwork`].
#[cfg(test)]
pub(crate) trait FakeNetworkContext {
/// The type of timer IDs installed by this context.
type TimerId;
/// The type of metadata associated with frames sent by this context.
type SendMeta;
/// The type of metadata associated with frames received by this
/// context.
type RecvMeta;
/// Handles a single received frame in this context.
fn handle_frame(&mut self, recv: Self::RecvMeta, data: Buf<Vec<u8>>);
/// Handles a single timer id in this context.
fn handle_timer(&mut self, timer: Self::TimerId);
/// Processes any context-internal queues, returning `true` if any work
/// was done.
///
/// This is used to drive queued frames that may be sitting inside the
/// context and invisible to the [`FakeNetwork`].
fn process_queues(&mut self) -> bool;
}
/// A set of links in a `FakeNetwork`.
///
/// A `FakeNetworkLinks` represents the set of links in a `FakeNetwork`.
/// It exposes the link information by providing the ability to map from a
/// frame's sending metadata - including its context, local state, and
/// `SendMeta` - to the set of appropriate receivers, each represented by
/// a context ID, receive metadata, and latency.
#[cfg(test)]
pub(crate) trait FakeNetworkLinks<SendMeta, RecvMeta, CtxId> {
fn map_link(&self, ctx: CtxId, meta: SendMeta) -> Vec<(CtxId, RecvMeta, Option<Duration>)>;
}
#[cfg(test)]
impl<
SendMeta,
RecvMeta,
CtxId,
F: Fn(CtxId, SendMeta) -> Vec<(CtxId, RecvMeta, Option<Duration>)>,
> FakeNetworkLinks<SendMeta, RecvMeta, CtxId> for F
{
fn map_link(&self, ctx: CtxId, meta: SendMeta) -> Vec<(CtxId, RecvMeta, Option<Duration>)> {
(self)(ctx, meta)
}
}
/// The result of a single step in a `FakeNetwork`
#[cfg(test)]
#[derive(Debug)]
pub(crate) struct StepResult {
pub(crate) timers_fired: usize,
pub(crate) frames_sent: usize,
pub(crate) contexts_with_queued_frames: usize,
}
#[cfg(test)]
impl StepResult {
fn new(
timers_fired: usize,
frames_sent: usize,
contexts_with_queued_frames: usize,
) -> Self {
Self { timers_fired, frames_sent, contexts_with_queued_frames }
}
fn new_idle() -> Self {
Self::new(0, 0, 0)
}
/// Returns `true` if the last step did not perform any operations.
pub(crate) fn is_idle(&self) -> bool {
return self.timers_fired == 0
&& self.frames_sent == 0
&& self.contexts_with_queued_frames == 0;
}
}
#[cfg(test)]
impl<CtxId, Ctx, Links> FakeNetwork<CtxId, Ctx, Links>
where
CtxId: Eq + Hash + Copy + Debug,
Ctx: FakeNetworkContext,
Links: FakeNetworkLinks<Ctx::SendMeta, Ctx::RecvMeta, CtxId>,
{
/// Retrieves a context named `context`.
pub(crate) fn context<K: Into<CtxId>>(&mut self, context: K) -> &mut Ctx {
self.contexts.get_mut(&context.into()).unwrap()
}
pub(crate) fn with_context<K: Into<CtxId>, O, F: FnOnce(&mut Ctx) -> O>(
&mut self,
context: K,
f: F,
) -> O {
f(self.context(context))
}
}
#[cfg(test)]
impl<CtxId, Ctx, Links> FakeNetwork<CtxId, Ctx, Links>
where
CtxId: Eq + Hash + Copy + Debug,
Ctx: FakeNetworkContext
+ WithFakeTimerContext<Ctx::TimerId>
+ WithFakeFrameContext<Ctx::SendMeta>,
Ctx::TimerId: Clone,
Links: FakeNetworkLinks<Ctx::SendMeta, Ctx::RecvMeta, CtxId>,
{
/// Creates a new `FakeNetwork`.
///
/// Creates a new `FakeNetwork` with the collection of `FakeCoreCtx`s in
/// `contexts`. `Ctx`s are named by type parameter `CtxId`.
///
/// # Panics
///
/// Calls to `new` will panic if given a `FakeCoreCtx` with timer events.
/// `FakeCoreCtx`s given to `FakeNetwork` **must not** have any timer
/// events already attached to them, because `FakeNetwork` maintains
/// all the internal timers in dispatchers in sync to enable synchronous
/// simulation steps.
pub(crate) fn new<I: IntoIterator<Item = (CtxId, Ctx)>>(contexts: I, links: Links) -> Self {
let mut contexts = contexts.into_iter().collect::<HashMap<_, _>>();
// Take the current time to be the latest of the times of any of the
// contexts. This ensures that no context has state which is based
// on having observed a time in the future, which could cause bugs.
// For any contexts which have a time further in the past, it will
// appear as though time has jumped forwards, but that's fine. The
// only way that this could be a problem would be if a timer were
// installed which should have fired in the interim (code might
// become buggy in this case). However, we assert below that no
// timers are installed.
let latest_time = contexts
.iter()
.map(|(_, ctx)| ctx.with_fake_timer_ctx(|ctx| ctx.instant.time))
.max()
// If `max` returns `None`, it means that we were called with no
// contexts. That's kind of silly, but whatever - arbitrarily
// choose the current time as the epoch.
.unwrap_or(FakeInstant::default());
assert!(
!contexts
.iter()
.any(|(_, ctx)| { !ctx.with_fake_timer_ctx(|ctx| ctx.timers.is_empty()) }),
"can't start network with contexts that already have timers set"
);
// Synchronize all contexts' current time to the latest time of any
// of the contexts. See comment above for more details.
for (_, ctx) in contexts.iter_mut() {
ctx.with_fake_timer_ctx_mut(|ctx| ctx.instant.time = latest_time);
}
Self { contexts, current_time: latest_time, pending_frames: BinaryHeap::new(), links }
}
/// Iterates over pending frames in an arbitrary order.
pub(crate) fn iter_pending_frames(
&self,
) -> impl Iterator<Item = &PendingFrame<CtxId, Ctx::RecvMeta>> {
self.pending_frames.iter()
}
/// Drops all pending frames; they will not be delivered.
pub(crate) fn drop_pending_frames(&mut self) {
self.pending_frames.clear();
}
/// Performs a single step in network simulation.
///
/// `step` performs a single logical step in the collection of `Ctx`s
/// held by this `FakeNetwork`. A single step consists of the following
/// operations:
///
/// - All pending frames, kept in each `FakeCoreCtx`, are mapped to their
/// destination context/device pairs and moved to an internal
/// collection of pending frames.
/// - The collection of pending timers and scheduled frames is inspected
/// and a simulation time step is retrieved, which will cause a next
/// event to trigger. The simulation time is updated to the new time.
/// - All scheduled frames whose deadline is less than or equal to the
/// new simulation time are sent to their destinations, handled using
/// `handle_frame`.
/// - All timer events whose deadline is less than or equal to the new
/// simulation time are fired, handled using `handle_timer`.
///
/// If any new events are created during the operation of frames or
/// timers, they **will not** be taken into account in the current
/// `step`. That is, `step` collects all the pending events before
/// dispatching them, ensuring that an infinite loop can't be created as
/// a side effect of calling `step`.
///
/// The return value of `step` indicates which of the operations were
/// performed.
///
/// # Panics
///
/// If `FakeNetwork` was set up with a bad `links`, calls to `step` may
/// panic when trying to route frames to their context/device
/// destinations.
pub(crate) fn step(&mut self) -> StepResult
where
Ctx::TimerId: core::fmt::Debug,
{
self.step_with(|_, meta, buf| Some((meta, buf)))
}
/// Like [`FakeNetwork::step`], but receives a function
/// `filter_map_frame` that can modify the an inbound frame before
/// delivery or drop it altogether by returning `None`.
pub(crate) fn step_with<
F: FnMut(&mut Ctx, Ctx::RecvMeta, Buf<Vec<u8>>) -> Option<(Ctx::RecvMeta, Buf<Vec<u8>>)>,
>(
&mut self,
mut filter_map_frame: F,
) -> StepResult
where
Ctx::TimerId: core::fmt::Debug,
{
let mut ret = StepResult::new_idle();
// Drive all queues before checking for the network and time
// simulation.
for (_, ctx) in self.contexts.iter_mut() {
if ctx.process_queues() {
ret.contexts_with_queued_frames += 1;
}
}
self.collect_frames();
let next_step = if let Some(t) = self.next_step() {
t
} else {
return ret;
};
// This assertion holds the contract that `next_step` does not
// return a time in the past.
assert!(next_step >= self.current_time);
// Move time forward:
self.current_time = next_step;
for (_, ctx) in self.contexts.iter_mut() {
ctx.with_fake_timer_ctx_mut(|ctx| ctx.instant.time = next_step);
}
// Dispatch all pending frames:
while let Some(InstantAndData(t, _)) = self.pending_frames.peek() {
// TODO(https://github.com/rust-lang/rust/issues/53667): Remove
// this break once let_chains is stable.
if *t > self.current_time {
break;
}
// We can unwrap because we just peeked.
let PendingFrameData { dst_context, meta, frame } =
self.pending_frames.pop().unwrap().1;
let dst_context = self.context(dst_context);
if let Some((meta, frame)) =
filter_map_frame(dst_context, meta, Buf::new(frame, ..))
{
dst_context.handle_frame(meta, frame)
}
ret.frames_sent += 1;
}
// Dispatch all pending timers.
for (_, ctx) in self.contexts.iter_mut() {
// We have to collect the timers before dispatching them, to
// avoid an infinite loop in case handle_timer schedules another
// timer for the same or older FakeInstant.
let mut timers = Vec::<Ctx::TimerId>::new();
ctx.with_fake_timer_ctx_mut(|ctx| {
while let Some(InstantAndData(t, id)) = ctx.timers.peek() {
// TODO(https://github.com/rust-lang/rust/issues/53667):
// Remove this break once let_chains is stable.
if *t > ctx.now() {
break;
}
timers.push(id.clone());
assert_ne!(ctx.timers.pop(), None);
}
});
for t in timers {
ctx.handle_timer(t);
ret.timers_fired += 1;
}
}
ret
}
/// Runs the network until it is starved of events.
///
/// # Panics
///
/// Panics if 1,000,000 steps are performed without becoming idle.
/// Also panics under the same conditions as [`step`].
pub(crate) fn run_until_idle(&mut self)
where
Ctx::TimerId: core::fmt::Debug,
{
self.run_until_idle_with(|_, meta, frame| Some((meta, frame)))
}
/// Like [`FakeNetwork::run_until_idle`] but receives a function
/// `filter_map_frame` that can modify the an inbound frame before
/// delivery or drop it altogether by returning `None`.
pub(crate) fn run_until_idle_with<
F: FnMut(&mut Ctx, Ctx::RecvMeta, Buf<Vec<u8>>) -> Option<(Ctx::RecvMeta, Buf<Vec<u8>>)>,
>(
&mut self,
mut filter_map_frame: F,
) where
Ctx::TimerId: core::fmt::Debug,
{
for _ in 0..1_000_000 {
if self.step_with(&mut filter_map_frame).is_idle() {
return;
}
}
panic!("FakeNetwork seems to have gotten stuck in a loop.");
}
/// Collects all queued frames.
///
/// Collects all pending frames and schedules them for delivery to the
/// destination context/device based on the result of `links`. The
/// collected frames are queued for dispatching in the `FakeNetwork`,
/// ordered by their scheduled delivery time given by the latency result
/// provided by `links`.
pub(crate) fn collect_frames(&mut self) {
let all_frames: Vec<(CtxId, Vec<(Ctx::SendMeta, Vec<u8>)>)> = self
.contexts
.iter_mut()
.filter_map(|(n, ctx)| {
ctx.with_fake_frame_ctx_mut(|ctx| {
if ctx.frames.is_empty() {
None
} else {
Some((n.clone(), ctx.frames.drain(..).collect()))
}
})
})
.collect();
for (src_context, frames) in all_frames.into_iter() {
for (send_meta, frame) in frames.into_iter() {
for (dst_context, recv_meta, latency) in
self.links.map_link(src_context, send_meta)
{
self.pending_frames.push(PendingFrame::new(
self.current_time + latency.unwrap_or(Duration::from_millis(0)),
PendingFrameData { frame: frame.clone(), dst_context, meta: recv_meta },
));
}
}
}
}
/// Calculates the next `FakeInstant` when events are available.
///
/// Returns the smallest `FakeInstant` greater than or equal to the
/// current time for which an event is available. If no events are
/// available, returns `None`.
pub(crate) fn next_step(&self) -> Option<FakeInstant> {
// Get earliest timer in all contexts.
let next_timer = self
.contexts
.iter()
.filter_map(|(_, ctx)| {
ctx.with_fake_timer_ctx(|ctx| match ctx.timers.peek() {
Some(tmr) => Some(tmr.0),
None => None,
})
})
.min();
// Get the instant for the next packet.
let next_packet_due = self.pending_frames.peek().map(|t| t.0);
// Return the earliest of them both, and protect against returning a
// time in the past.
match next_timer {
Some(t) if next_packet_due.is_some() => Some(t).min(next_packet_due),
Some(t) => Some(t),
None => next_packet_due,
}
.map(|t| t.max(self.current_time))
}
}
#[cfg(test)]
impl<CtxId, Links, CC, BC> FakeNetwork<CtxId, crate::testutil::ContextPair<CC, BC>, Links>
where
crate::testutil::ContextPair<CC, BC>: FakeNetworkContext,
CtxId: Eq + Hash + Copy + Debug,
Links: FakeNetworkLinks<
<crate::testutil::ContextPair<CC, BC> as FakeNetworkContext>::SendMeta,
<crate::testutil::ContextPair<CC, BC> as FakeNetworkContext>::RecvMeta,
CtxId,
>,
{
/// Retrieves a `FakeCoreCtx` named `context`.
pub(crate) fn core_ctx<K: Into<CtxId>>(&mut self, context: K) -> &mut CC {
let crate::testutil::ContextPair { core_ctx, bindings_ctx: _ } = self.context(context);
core_ctx
}
/// Retrieves a `FakeBindingsCtx` named `context`.
pub(crate) fn bindings_ctx<K: Into<CtxId>>(&mut self, context: K) -> &mut BC {
let crate::testutil::ContextPair { core_ctx: _, bindings_ctx } = self.context(context);
bindings_ctx
}
}
/// Creates a new [`FakeNetwork`] of [`Ctx`]s in a simple two-host
/// configuration.
///
/// Two hosts are created with the given names. Packets emitted by one
/// arrive at the other and vice-versa.
#[cfg(test)]
pub(crate) fn new_simple_fake_network<CtxId: Copy + Debug + Hash + Eq>(
a_id: CtxId,
a: crate::testutil::FakeCtx,
a_device_id: EthernetWeakDeviceId<crate::testutil::FakeBindingsCtx>,
b_id: CtxId,
b: crate::testutil::FakeCtx,
b_device_id: EthernetWeakDeviceId<crate::testutil::FakeBindingsCtx>,
) -> FakeNetwork<
CtxId,
crate::testutil::FakeCtx,
impl FakeNetworkLinks<
DispatchedFrame,
EthernetDeviceId<crate::testutil::FakeBindingsCtx>,
CtxId,
>,
> {
let contexts = vec![(a_id, a), (b_id, b)].into_iter();
FakeNetwork::new(contexts, move |net, _frame: DispatchedFrame| {
if net == a_id {
b_device_id
.upgrade()
.map(|device_id| (b_id, device_id, None))
.into_iter()
.collect::<Vec<_>>()
} else {
a_device_id
.upgrade()
.map(|device_id| (a_id, device_id, None))
.into_iter()
.collect::<Vec<_>>()
}
})
}
#[cfg(test)]
mod tests {
use crate::device::testutil::FakeDeviceId;
use super::*;
const ONE_SEC: Duration = Duration::from_secs(1);
const ONE_SEC_INSTANT: FakeInstant = FakeInstant { offset: ONE_SEC };
#[test]
fn test_instant_and_data() {
// Verify implementation of InstantAndData to be used as a complex
// type in a BinaryHeap.
let mut heap = BinaryHeap::<InstantAndData<usize>>::new();
let now = FakeInstant::default();
fn new_data(time: FakeInstant, id: usize) -> InstantAndData<usize> {
InstantAndData::new(time, id)
}
heap.push(new_data(now + Duration::from_secs(1), 1));
heap.push(new_data(now + Duration::from_secs(2), 2));
// Earlier timer is popped first.
assert_eq!(heap.pop().unwrap().1, 1);
assert_eq!(heap.pop().unwrap().1, 2);
assert_eq!(heap.pop(), None);
heap.push(new_data(now + Duration::from_secs(1), 1));
heap.push(new_data(now + Duration::from_secs(1), 1));
// Can pop twice with identical data.
assert_eq!(heap.pop().unwrap().1, 1);
assert_eq!(heap.pop().unwrap().1, 1);
assert_eq!(heap.pop(), None);
}
#[test]
fn test_fake_timer_context() {
// An implementation of `TimerContext` that uses `usize` timer IDs
// and stores every timer in a `Vec`.
impl<M, E: Debug, D, S, F> TimerHandler<FakeBindingsCtx<usize, E, S, F>, usize>
for FakeCoreCtx<Vec<(usize, FakeInstant)>, M, D>
{
fn handle_timer(
&mut self,
bindings_ctx: &mut FakeBindingsCtx<usize, E, S, F>,
id: usize,
) {
let now = bindings_ctx.now();
self.get_mut().push((id, now));
}
}
let new_ctx =
|| FakeCtx::<Vec<(usize, FakeInstant)>, usize, (), (), FakeDeviceId, ()>::default();
let FakeCtx { mut core_ctx, mut bindings_ctx } = new_ctx();
// When no timers are installed, `trigger_next_timer` should return
// `false`.
assert_eq!(bindings_ctx.trigger_next_timer(&mut core_ctx), None);
assert_eq!(core_ctx.get_ref().as_slice(), []);
// When one timer is installed, it should be triggered.
let FakeCtx { mut core_ctx, mut bindings_ctx } = new_ctx();
// No timer with id `0` exists yet.
assert_eq!(bindings_ctx.scheduled_instant(0), None);
assert_eq!(bindings_ctx.schedule_timer(ONE_SEC, 0), None);
// Timer with id `0` scheduled to execute at `ONE_SEC_INSTANT`.
assert_eq!(bindings_ctx.scheduled_instant(0).unwrap(), ONE_SEC_INSTANT);
assert_eq!(bindings_ctx.trigger_next_timer(&mut core_ctx), Some(0));
assert_eq!(core_ctx.get_ref().as_slice(), [(0, ONE_SEC_INSTANT)]);
// After the timer fires, it should not still be scheduled at some
// instant.
assert_eq!(bindings_ctx.scheduled_instant(0), None);
// The time should have been advanced.
assert_eq!(bindings_ctx.now(), ONE_SEC_INSTANT);
// Once it's been triggered, it should be canceled and not
// triggerable again.
let FakeCtx { mut core_ctx, mut bindings_ctx } = new_ctx();
assert_eq!(bindings_ctx.trigger_next_timer(&mut core_ctx), None);
assert_eq!(core_ctx.get_ref().as_slice(), []);
// If we schedule a timer but then cancel it, it shouldn't fire.
let FakeCtx { mut core_ctx, mut bindings_ctx } = new_ctx();
assert_eq!(bindings_ctx.schedule_timer(ONE_SEC, 0), None);
assert_eq!(bindings_ctx.cancel_timer(0), Some(ONE_SEC_INSTANT));
assert_eq!(bindings_ctx.trigger_next_timer(&mut core_ctx), None);
assert_eq!(core_ctx.get_ref().as_slice(), []);
// If we schedule a timer but then schedule the same ID again, the
// second timer should overwrite the first one.
let FakeCtx { core_ctx: _, mut bindings_ctx } = new_ctx();
assert_eq!(bindings_ctx.schedule_timer(Duration::from_secs(0), 0), None);
assert_eq!(
bindings_ctx.schedule_timer(ONE_SEC, 0),
Some(Duration::from_secs(0).into())
);
assert_eq!(bindings_ctx.cancel_timer(0), Some(ONE_SEC_INSTANT));
// If we schedule three timers and then run `trigger_timers_until`
// with the appropriate value, only two of them should fire.
let FakeCtx { mut core_ctx, mut bindings_ctx } = new_ctx();
assert_eq!(bindings_ctx.schedule_timer(Duration::from_secs(0), 0), None,);
assert_eq!(bindings_ctx.schedule_timer(Duration::from_secs(1), 1), None,);
assert_eq!(bindings_ctx.schedule_timer(Duration::from_secs(2), 2), None,);
assert_eq!(
bindings_ctx.trigger_timers_until_instant(ONE_SEC_INSTANT, &mut core_ctx),
vec![0, 1],
);
// The first two timers should have fired.
assert_eq!(
core_ctx.get_ref().as_slice(),
[(0, FakeInstant::from(Duration::from_secs(0))), (1, ONE_SEC_INSTANT)]
);
// They should be canceled now.
assert_eq!(bindings_ctx.cancel_timer(0), None);
assert_eq!(bindings_ctx.cancel_timer(1), None);
// The clock should have been updated.
assert_eq!(bindings_ctx.now(), ONE_SEC_INSTANT);
// The last timer should not have fired.
assert_eq!(
bindings_ctx.cancel_timer(2),
Some(FakeInstant::from(Duration::from_secs(2)))
);
}
#[test]
fn test_trigger_timers_until_and_expect_unordered() {
// If the requested instant does not coincide with a timer trigger
// point, the time should still be advanced.
let FakeCtx { mut core_ctx, mut bindings_ctx } =
FakeCtx::<Vec<(usize, FakeInstant)>, usize, (), (), FakeDeviceId, ()>::default();
assert_eq!(bindings_ctx.schedule_timer(Duration::from_secs(0), 0), None);
assert_eq!(bindings_ctx.schedule_timer(Duration::from_secs(2), 1), None);
bindings_ctx.trigger_timers_until_and_expect_unordered(
ONE_SEC_INSTANT,
vec![0],
&mut core_ctx,
);
assert_eq!(bindings_ctx.now(), ONE_SEC_INSTANT);
}
}
}