Move resize thread handling to separate module

This commit is contained in:
Alexandre Bury 2018-07-19 20:54:45 -07:00
parent f4530d688b
commit 6a728bf234
5 changed files with 61 additions and 56 deletions

View File

@ -305,7 +305,7 @@ impl backend::Backend for Backend {
) {
let running = Arc::new(AtomicBool::new(true));
backend::start_resize_thread(
backend::resize::start_resize_thread(
self.signals.take().unwrap(),
event_sink.clone(),
input_request.clone(),

View File

@ -457,7 +457,7 @@ impl backend::Backend for Backend {
#[cfg(unix)]
{
backend::start_resize_thread(
backend::resize::start_resize_thread(
self.signals.take().unwrap(),
event_sink.clone(),
input_request.clone(),

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@ -7,19 +7,15 @@
//! using some common libraries. Each of those included backends needs a
//! corresonding feature to be enabled.
use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::Arc;
use std::thread;
use crossbeam_channel::{Receiver, Sender};
#[cfg(unix)]
use signal_hook::iterator::Signals;
use event::Event;
use theme;
use vec::Vec2;
#[cfg(unix)]
mod resize;
pub mod dummy;
pub mod blt;
@ -91,49 +87,3 @@ pub trait Backend {
/// Disables the given effect.
fn unset_effect(&self, effect: theme::Effect);
}
/// This starts a new thread to listen for SIGWINCH signals
///
/// As long as `resize_running` is true, it will listen for SIGWINCH, and,
/// when detected, it wil set `needs_resize` to true and send an event to
/// `resize_sender`. It will also consume an event from `resize_requests`
/// afterward, to keep the balance in the force.
#[cfg(unix)]
fn start_resize_thread(
signals: Signals, resize_sender: Sender<Option<Event>>,
resize_requests: Receiver<InputRequest>, resize_running: Arc<AtomicBool>,
needs_resize: Option<Arc<AtomicBool>>,
) {
thread::spawn(move || {
// This thread will listen to SIGWINCH events and report them.
while resize_running.load(Ordering::Relaxed) {
// We know it will only contain SIGWINCH signals, so no need to check.
if signals.wait().count() > 0 {
// Tell ncurses about the new terminal size.
// Well, do the actual resizing later on, in the main thread.
// Ncurses isn't really thread-safe so calling resize_term() can crash
// other calls like clear() or refresh().
if let Some(ref needs_resize) = needs_resize {
needs_resize.store(true, Ordering::Relaxed);
}
resize_sender.send(Some(Event::WindowResize));
// We've sent the message.
// This means Cursive was listening, and will now soon be sending a new request.
// This means the input thread accepted a request, but hasn't sent a message yet.
// So we KNOW the input thread is not waiting for a new request.
// We sent an event for free, so pay for it now by consuming a request
while let Some(InputRequest::Peek) = resize_requests.recv() {
// At this point Cursive will now listen for input.
// There is a chance the input thread will send his event before us.
// But without some extra atomic flag, it'd be hard to know.
// So instead, keep sending `None`
// Repeat until we receive a blocking call
resize_sender.send(None);
}
}
}
});
}

55
src/backend/resize.rs Normal file
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@ -0,0 +1,55 @@
use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::Arc;
use std::thread;
use crossbeam_channel::{Receiver, Sender};
use signal_hook::iterator::Signals;
use backend::InputRequest;
use event::Event;
/// This starts a new thread to listen for SIGWINCH signals
///
/// As long as `resize_running` is true, it will listen for SIGWINCH, and,
/// when detected, it wil set `needs_resize` to true and send an event to
/// `resize_sender`. It will also consume an event from `resize_requests`
/// afterward, to keep the balance in the force.
#[cfg(unix)]
pub fn start_resize_thread(
signals: Signals, resize_sender: Sender<Option<Event>>,
resize_requests: Receiver<InputRequest>, resize_running: Arc<AtomicBool>,
needs_resize: Option<Arc<AtomicBool>>,
) {
thread::spawn(move || {
// This thread will listen to SIGWINCH events and report them.
while resize_running.load(Ordering::Relaxed) {
// We know it will only contain SIGWINCH signals, so no need to check.
if signals.wait().count() > 0 {
// Tell ncurses about the new terminal size.
// Well, do the actual resizing later on, in the main thread.
// Ncurses isn't really thread-safe so calling resize_term() can crash
// other calls like clear() or refresh().
if let Some(ref needs_resize) = needs_resize {
needs_resize.store(true, Ordering::Relaxed);
}
resize_sender.send(Some(Event::WindowResize));
// We've sent the message.
// This means Cursive was listening, and will now soon be sending a new request.
// This means the input thread accepted a request, but hasn't sent a message yet.
// So we KNOW the input thread is not waiting for a new request.
// We sent an event for free, so pay for it now by consuming a request
while let Some(InputRequest::Peek) = resize_requests.recv() {
// At this point Cursive will now listen for input.
// There is a chance the input thread will send his event before us.
// But without some extra atomic flag, it'd be hard to know.
// So instead, keep sending `None`
// Repeat until we receive a blocking call
resize_sender.send(None);
}
}
}
});
}

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@ -298,7 +298,7 @@ impl backend::Backend for Backend {
#[cfg(unix)]
{
backend::start_resize_thread(
backend::resize::start_resize_thread(
Signals::new(&[libc::SIGWINCH]).unwrap(),
event_sink.clone(),
input_request.clone(),