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//! Mock version of std::fs::File;
use mockall::mock;
use crate::sync::oneshot;
use std::{
cell::RefCell,
collections::VecDeque,
fs::{Metadata, Permissions},
future::Future,
io::{self, Read, Seek, SeekFrom, Write},
path::PathBuf,
pin::Pin,
task::{Context, Poll},
};
mock! {
#[derive(Debug)]
pub File {
pub fn create(pb: PathBuf) -> io::Result<Self>;
// These inner_ methods exist because std::fs::File has two
// implementations for each of these methods: one on "&mut self" and
// one on "&&self". Defining both of those in terms of an inner_ method
// allows us to specify the expectation the same way, regardless of
// which method is used.
pub fn inner_flush(&self) -> io::Result<()>;
pub fn inner_read(&self, dst: &mut [u8]) -> io::Result<usize>;
pub fn inner_seek(&self, pos: SeekFrom) -> io::Result<u64>;
pub fn inner_write(&self, src: &[u8]) -> io::Result<usize>;
pub fn metadata(&self) -> io::Result<Metadata>;
pub fn open(pb: PathBuf) -> io::Result<Self>;
pub fn set_len(&self, size: u64) -> io::Result<()>;
pub fn set_permissions(&self, _perm: Permissions) -> io::Result<()>;
pub fn set_max_buf_size(&self, max_buf_size: usize);
pub fn sync_all(&self) -> io::Result<()>;
pub fn sync_data(&self) -> io::Result<()>;
pub fn try_clone(&self) -> io::Result<Self>;
}
#[cfg(windows)]
impl std::os::windows::io::AsRawHandle for File {
fn as_raw_handle(&self) -> std::os::windows::io::RawHandle;
}
#[cfg(windows)]
impl std::os::windows::io::FromRawHandle for File {
unsafe fn from_raw_handle(h: std::os::windows::io::RawHandle) -> Self;
}
#[cfg(unix)]
impl std::os::unix::io::AsRawFd for File {
fn as_raw_fd(&self) -> std::os::unix::io::RawFd;
}
#[cfg(unix)]
impl std::os::unix::io::FromRawFd for File {
unsafe fn from_raw_fd(h: std::os::unix::io::RawFd) -> Self;
}
}
impl Read for MockFile {
fn read(&mut self, dst: &mut [u8]) -> io::Result<usize> {
self.inner_read(dst)
}
}
impl Read for &'_ MockFile {
fn read(&mut self, dst: &mut [u8]) -> io::Result<usize> {
self.inner_read(dst)
}
}
impl Seek for &'_ MockFile {
fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> {
self.inner_seek(pos)
}
}
impl Write for &'_ MockFile {
fn write(&mut self, src: &[u8]) -> io::Result<usize> {
self.inner_write(src)
}
fn flush(&mut self) -> io::Result<()> {
self.inner_flush()
}
}
tokio_thread_local! {
static QUEUE: RefCell<VecDeque<Box<dyn FnOnce() + Send>>> = RefCell::new(VecDeque::new())
}
#[derive(Debug)]
pub(super) struct JoinHandle<T> {
rx: oneshot::Receiver<T>,
}
pub(super) fn spawn_blocking<F, R>(f: F) -> JoinHandle<R>
where
F: FnOnce() -> R + Send + 'static,
R: Send + 'static,
{
let (tx, rx) = oneshot::channel();
let task = Box::new(move || {
let _ = tx.send(f());
});
QUEUE.with(|cell| cell.borrow_mut().push_back(task));
JoinHandle { rx }
}
pub(super) fn spawn_mandatory_blocking<F, R>(f: F) -> Option<JoinHandle<R>>
where
F: FnOnce() -> R + Send + 'static,
R: Send + 'static,
{
let (tx, rx) = oneshot::channel();
let task = Box::new(move || {
let _ = tx.send(f());
});
QUEUE.with(|cell| cell.borrow_mut().push_back(task));
Some(JoinHandle { rx })
}
impl<T> Future for JoinHandle<T> {
type Output = Result<T, io::Error>;
fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
use std::task::Poll;
match Pin::new(&mut self.rx).poll(cx) {
Poll::Ready(Ok(v)) => Poll::Ready(Ok(v)),
Poll::Ready(Err(e)) => panic!("error = {:?}", e),
Poll::Pending => Poll::Pending,
}
}
}
pub(super) mod pool {
use super::*;
pub(in super::super) fn len() -> usize {
QUEUE.with(|cell| cell.borrow().len())
}
pub(in super::super) fn run_one() {
let task = QUEUE
.with(|cell| cell.borrow_mut().pop_front())
.expect("expected task to run, but none ready");
task();
}
}