alacritty/src/main.rs

278 lines
8.0 KiB
Rust

// Copyright 2016 Joe Wilm, The Alacritty Project Contributors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//! Alacritty - The GPU Enhanced Terminal
#![feature(question_mark)]
#![feature(inclusive_range_syntax)]
#![feature(drop_types_in_const)]
#![allow(stable_features)] // lying about question_mark because 1.14.0 isn't released!
#![feature(proc_macro)]
#[macro_use]
extern crate serde_derive;
#[macro_use]
extern crate alacritty;
extern crate cgmath;
extern crate copypasta;
extern crate errno;
extern crate font;
extern crate glutin;
extern crate libc;
extern crate mio;
extern crate notify;
extern crate parking_lot;
extern crate serde;
extern crate serde_json;
extern crate serde_yaml;
extern crate vte;
#[macro_use]
extern crate bitflags;
use std::error::Error;
use std::sync::{mpsc, Arc};
use std::rc::Rc;
use alacritty::cli;
use alacritty::config::{self, Config};
use alacritty::display::{self, Display};
use alacritty::event;
use alacritty::event_loop::EventLoop;
use alacritty::input;
use alacritty::sync::FairMutex;
use alacritty::term::{Term};
use alacritty::tty::{self, process_should_exit};
fn main() {
// Load configuration
let config = match Config::load() {
// Error loading config
Err(err) => match err {
// Use default config when not found
config::Error::NotFound => {
err_println!("Config file not found; using defaults");
Config::default()
},
// If there's a problem with the config file, print an error
// and exit.
_ => die!("{}", err),
},
// Successfully loaded config from file
Ok(config) => config
};
// Load command line options
let options = cli::Options::load();
// Run alacritty
if let Err(err) = run(config, options) {
die!("{}", err);
}
println!("Goodbye");
}
/// Run Alacritty
///
/// Currently, these operations take place in this order.
/// 1. create a window
/// 2. create font rasterizer
/// 3. create quad renderer
/// 4. create glyph cache
/// 5. resize window/renderer using info from glyph cache / rasterizer
/// 6. create a pty
/// 7. create the terminal
/// 8. set resize callback on the window
/// 9. create event loop
/// 10. create display
/// 11. create input processor
/// 12. create config reloader
/// 13. enter main loop
///
/// Observations:
/// * The window + quad renderer + glyph cache and display are closely
/// related Actually, probably include the input processor as well.
/// The resize callback can be lumped in there and that resize step.
/// Rasterizer as well. Maybe we can lump *all* of this into the
/// `Display`.
/// * the pty and event loop closely related
/// * The term bridges the display and pty
/// * Main loop currently manages input, config reload events, drawing, and
/// exiting
///
/// It would be *really* great if this could read more like
///
/// ```ignore
/// let display = Display::new(args..);
/// let pty = Pty::new(display.size());
/// let term = Arc::new(Term::new(display.size());
/// let io_loop = Loop::new(Pty::new(display.size()), term.clone());
/// let config_reloader = config::Monitor::new(&config);
///
/// loop {
/// force_draw = false;
/// // Wait for something to happen
/// processor.process_events(&display);
///
/// // Handle config reloads
/// if let Ok(config) = config_rx.try_recv() {
/// force_draw = true;
/// display.update_config(&config);
/// processor.update_config(&config);
/// }
///
/// // Maybe draw the terminal
/// let terminal = terminal.lock();
/// signal_flag.set(false);
/// if force_draw || terminal.dirty {
/// display.draw(terminal, &config);
/// drop(terminal);
/// display.swap_buffers();
/// }
///
/// // Begin shutdown if the flag was raised.
/// if process_should_exit() {
/// break;
/// }
/// }
/// ```
///
/// instead of the 200 line monster it currently is.
///
fn run(config: Config, options: cli::Options) -> Result<(), Box<Error>> {
// Create a display.
//
// The display manages a window and can draw the terminal
let mut display = Display::new(&config, &options)?;
// Create the terminal
//
// This object contains all of the state about what's being displayed. It's
// wrapped in a clonable mutex since both the I/O loop and display need to
// access it.
let terminal = Arc::new(FairMutex::new(Term::new(display.size().to_owned())));
// Create the pty
//
// The pty forks a process to run the shell on the slave side of the
// pseudoterminal. A file descriptor for the master side is retained for
// reading/writing to the shell.
let pty = Rc::new(tty::new(display.size()));
// When the display is resized, inform the kernel of changes to pty
// dimensions.
//
// TODO: The Rc on pty is needed due to a borrowck error here. The borrow
// checker says that `pty` is still borrowed when it is dropped at the end
// of the `run` function.
let pty_ref = pty.clone();
display.set_resize_callback(move |size| {
pty_ref.resize(size);
});
// Create the pseudoterminal I/O loop
//
// pty I/O is ran on another thread as to not occupy cycles used by the
// renderer and input processing. Note that access to the terminal state is
// synchronized since the I/O loop updates the state, and the display
// consumes it periodically.
let event_loop = EventLoop::new(
terminal.clone(),
display.notifier(),
pty.reader(),
options.ref_test,
);
let loop_tx = event_loop.channel();
let event_loop_handle = event_loop.spawn(None);
// Event processor
let resize_tx = display.resize_channel();
let mut processor = event::Processor::new(
input::LoopNotifier(loop_tx),
terminal.clone(),
resize_tx,
&config,
options.ref_test,
);
let (config_tx, config_rx) = mpsc::channel();
// create a config watcher when config is loaded from disk
let _config_reloader = config.path().map(|path| {
config::Watcher::new(path, ConfigHandler {
tx: config_tx,
loop_kicker: display.notifier(),
})
});
// Main loop
let mut config_updated = false;
loop {
// Wait for something to happen
processor.process_events(display.window());
// Handle config reloads
if let Ok(config) = config_rx.try_recv() {
config_updated = true;
display.update_config(&config);
processor.update_config(&config);
}
// Maybe draw the terminal
let terminal = terminal.lock();
if terminal.dirty || config_updated {
display.draw(terminal, &config);
}
// Begin shutdown if the flag was raised.
if process_should_exit() {
break;
}
}
// FIXME need file watcher to work with custom delegates before
// joining config reloader is possible
//
// HELP I don't know what I meant in the above fixme
// config_reloader.join().ok();
// shutdown
event_loop_handle.join().ok();
Ok(())
}
struct ConfigHandler {
tx: mpsc::Sender<config::Config>,
loop_kicker: display::Notifier,
}
impl config::OnConfigReload for ConfigHandler {
fn on_config_reload(&mut self, config: Config) {
if let Err(..) = self.tx.send(config) {
err_println!("Failed to notify of new config");
return;
}
self.loop_kicker.notify();
}
}