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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 crate::transport::device_selector::{DeviceID, DeviceSelectorEvent};
use crate::transport::platform::winapi::DeviceInfoSet;
use runloop::RunLoop;
use std::collections::{HashMap, HashSet};
use std::error::Error;
use std::iter::FromIterator;
use std::sync::{mpsc::Sender, Arc};
use std::thread;
use std::time::Duration;
pub struct Monitor<F>
where
F: Fn(String, Sender<DeviceSelectorEvent>, Sender<crate::StatusUpdate>, &dyn Fn() -> bool)
+ Sync,
{
runloops: HashMap<String, RunLoop>,
new_device_cb: Arc<F>,
selector_sender: Sender<DeviceSelectorEvent>,
status_sender: Sender<crate::StatusUpdate>,
}
impl<F> Monitor<F>
where
F: Fn(String, Sender<DeviceSelectorEvent>, Sender<crate::StatusUpdate>, &dyn Fn() -> bool)
+ Send
+ Sync
+ 'static,
{
pub fn new(
new_device_cb: F,
selector_sender: Sender<DeviceSelectorEvent>,
status_sender: Sender<crate::StatusUpdate>,
) -> Self {
Self {
runloops: HashMap::new(),
new_device_cb: Arc::new(new_device_cb),
selector_sender,
status_sender,
}
}
pub fn run(&mut self, alive: &dyn Fn() -> bool) -> Result<(), Box<dyn Error>> {
let mut current = HashSet::new();
let mut previous;
while alive() {
let device_info_set = DeviceInfoSet::new()?;
previous = current;
current = HashSet::from_iter(device_info_set.devices());
// Remove devices that are gone.
for path in previous.difference(¤t) {
self.remove_device(path);
}
let added: Vec<String> = current.difference(&previous).cloned().collect();
// We have to notify additions in batches to avoid
// arbitrarily selecting the first added device.
if !added.is_empty()
&& self
.selector_sender
.send(DeviceSelectorEvent::DevicesAdded(added.clone()))
.is_err()
{
// Send only fails if the receiver hung up. We should exit the loop.
break;
}
// Add devices that were plugged in.
for path in added {
self.add_device(&path);
}
// Wait a little before looking for devices again.
thread::sleep(Duration::from_millis(100));
}
// Remove all tracked devices.
self.remove_all_devices();
Ok(())
}
fn add_device(&mut self, path: &DeviceID) {
let f = self.new_device_cb.clone();
let path = path.clone();
let key = path.clone();
let selector_sender = self.selector_sender.clone();
let status_sender = self.status_sender.clone();
debug!("Adding device {}", path);
let runloop = RunLoop::new(move |alive| {
if alive() {
f(path, selector_sender, status_sender, alive);
}
});
if let Ok(runloop) = runloop {
self.runloops.insert(key, runloop);
}
}
fn remove_device(&mut self, path: &DeviceID) {
let _ = self
.selector_sender
.send(DeviceSelectorEvent::DeviceRemoved(path.clone()));
debug!("Removing device {}", path);
if let Some(runloop) = self.runloops.remove(path) {
runloop.cancel();
}
}
fn remove_all_devices(&mut self) {
while !self.runloops.is_empty() {
let path = self.runloops.keys().next().unwrap().clone();
self.remove_device(&path);
}
}
}