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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
use super::{
action::Action,
error::{BitsTaskError, ErrorStage, ErrorType},
};
use log::warn;
use xpcom::{RefCounted, ThreadBoundRefPtr};
#[derive(Debug, PartialEq, Clone, Copy)]
pub enum DataType {
Callback,
BitsService,
BitsRequest,
Observer,
Context,
}
#[derive(Debug, PartialEq, Clone, Copy)]
enum GetThreadboundError {
Missing,
WrongThread,
}
impl DataType {
fn error_type(&self, error: GetThreadboundError) -> ErrorType {
match self {
DataType::Callback => match error {
GetThreadboundError::Missing => ErrorType::MissingCallback,
GetThreadboundError::WrongThread => ErrorType::CallbackOnWrongThread,
},
DataType::BitsService => match error {
GetThreadboundError::Missing => ErrorType::MissingBitsService,
GetThreadboundError::WrongThread => ErrorType::BitsServiceOnWrongThread,
},
DataType::BitsRequest => match error {
GetThreadboundError::Missing => ErrorType::MissingBitsRequest,
GetThreadboundError::WrongThread => ErrorType::BitsRequestOnWrongThread,
},
DataType::Observer => match error {
GetThreadboundError::Missing => ErrorType::MissingObserver,
GetThreadboundError::WrongThread => ErrorType::ObserverOnWrongThread,
},
DataType::Context => match error {
GetThreadboundError::Missing => ErrorType::MissingContext,
GetThreadboundError::WrongThread => ErrorType::ContextOnWrongThread,
},
}
}
fn name(&self) -> &'static str {
match self {
DataType::Callback => "Callback",
DataType::BitsService => "BITS Service",
DataType::BitsRequest => "BITS Request",
DataType::Observer => "Observer",
DataType::Context => "Context",
}
}
}
/// Given a reference to a threadbound option
/// (i.e. `&Option<ThreadBoundRefPtr<_>>`), this function will attempt to
/// retrieve a reference to the value stored within. If it is not available
/// (option is `None` or value is on the wrong thread), `None` is returned
/// instead.
pub fn get_from_threadbound_option<T>(
maybe_threadbound: &Option<ThreadBoundRefPtr<T>>,
data_type: DataType,
action: Action,
) -> Option<&T>
where
T: RefCounted + 'static,
{
maybe_threadbound.as_ref().and_then(|threadbound| {
let maybe_reference = threadbound.get_ref();
if maybe_reference.is_none() {
warn!(
"Unexpected error {}: {} is on the wrong thread",
action.description(),
data_type.name(),
);
}
maybe_reference
})
}
/// Given a reference to a threadbound option
/// (i.e. `&Option<ThreadBoundRefPtr<_>>`), this function will attempt to
/// retrieve a reference to the value stored within. If it is not available
/// (option is `None` or value is on the wrong thread), a `BitsTaskError` is
/// returned instead.
pub fn expect_from_threadbound_option<T>(
maybe_threadbound: &Option<ThreadBoundRefPtr<T>>,
data_type: DataType,
action: Action,
) -> Result<&T, BitsTaskError>
where
T: RefCounted + 'static,
{
match maybe_threadbound.as_ref() {
Some(threadbound) => {
match threadbound.get_ref() {
Some(reference) => Ok(reference),
None => Err(BitsTaskError::new(
data_type.error_type(GetThreadboundError::WrongThread),
action,
// Retrieving data from threadbounds all happens on the main thread.
// No data is ever bound to other threads so there would be no
// reason to retrieve it there.
ErrorStage::MainThread,
)),
}
}
None => Err(BitsTaskError::new(
data_type.error_type(GetThreadboundError::Missing),
action,
// Retrieving data from threadbounds all happens on the main thread.
// No data is ever bound to other threads so there would be no
// reason to retrieve it there.
ErrorStage::MainThread,
)),
}
}