Split alacritty into a separate crates

The crate containing the entry point is called alacritty, and the crate
containing everything else is called alacritty_terminal.

1 files changed, 405 insertions, 0 deletions

diff --git a/alacritty_terminal/src/tty/unix.rs b/alacritty_terminal/src/tty/unix.rs
new file mode 100644
index 00000000..0e3dc2fd
--- /dev/null
+++ b/alacritty_terminal/src/tty/unix.rs
@@ -0,0 +1,405 @@
+// 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.
+//
+//! tty related functionality
+//!
+
+use crate::cli::Options;
+use crate::config::{Config, Shell};
+use crate::display::OnResize;
+use crate::term::SizeInfo;
+use crate::tty::{ChildEvent, EventedPty, EventedReadWrite};
+use mio;
+
+use libc::{self, c_int, pid_t, winsize, TIOCSCTTY};
+use nix::pty::openpty;
+use signal_hook::{self as sighook, iterator::Signals};
+
+use mio::unix::EventedFd;
+use std::ffi::CStr;
+use std::fs::File;
+use std::io;
+use std::os::unix::{
+    io::{AsRawFd, FromRawFd, RawFd},
+    process::CommandExt,
+};
+use std::process::{Child, Command, Stdio};
+use std::ptr;
+use std::sync::atomic::{AtomicUsize, Ordering};
+
+/// Process ID of child process
+///
+/// Necessary to put this in static storage for `sigchld` to have access
+static PID: AtomicUsize = AtomicUsize::new(0);
+
+pub fn child_pid() -> pid_t {
+    PID.load(Ordering::Relaxed) as pid_t
+}
+
+/// Get the current value of errno
+fn errno() -> c_int {
+    ::errno::errno().0
+}
+
+/// Get raw fds for master/slave ends of a new pty
+fn make_pty(size: winsize) -> (RawFd, RawFd) {
+    let mut win_size = size;
+    win_size.ws_xpixel = 0;
+    win_size.ws_ypixel = 0;
+
+    let ends = openpty(Some(&win_size), None).expect("openpty failed");
+
+    (ends.master, ends.slave)
+}
+
+/// Really only needed on BSD, but should be fine elsewhere
+fn set_controlling_terminal(fd: c_int) {
+    let res = unsafe {
+        // TIOSCTTY changes based on platform and the `ioctl` call is different
+        // based on architecture (32/64). So a generic cast is used to make sure
+        // there are no issues. To allow such a generic cast the clippy warning
+        // is disabled.
+        #[allow(clippy::cast_lossless)]
+        libc::ioctl(fd, TIOCSCTTY as _, 0)
+    };
+
+    if res < 0 {
+        die!("ioctl TIOCSCTTY failed: {}", errno());
+    }
+}
+
+#[derive(Debug)]
+struct Passwd<'a> {
+    name: &'a str,
+    passwd: &'a str,
+    uid: libc::uid_t,
+    gid: libc::gid_t,
+    gecos: &'a str,
+    dir: &'a str,
+    shell: &'a str,
+}
+
+/// Return a Passwd struct with pointers into the provided buf
+///
+/// # Unsafety
+///
+/// If `buf` is changed while `Passwd` is alive, bad thing will almost certainly happen.
+fn get_pw_entry(buf: &mut [i8; 1024]) -> Passwd<'_> {
+    // Create zeroed passwd struct
+    let mut entry: libc::passwd = unsafe { ::std::mem::uninitialized() };
+
+    let mut res: *mut libc::passwd = ptr::null_mut();
+
+    // Try and read the pw file.
+    let uid = unsafe { libc::getuid() };
+    let status = unsafe {
+        libc::getpwuid_r(uid, &mut entry, buf.as_mut_ptr() as *mut _, buf.len(), &mut res)
+    };
+
+    if status < 0 {
+        die!("getpwuid_r failed");
+    }
+
+    if res.is_null() {
+        die!("pw not found");
+    }
+
+    // sanity check
+    assert_eq!(entry.pw_uid, uid);
+
+    // Build a borrowed Passwd struct
+    Passwd {
+        name: unsafe { CStr::from_ptr(entry.pw_name).to_str().unwrap() },
+        passwd: unsafe { CStr::from_ptr(entry.pw_passwd).to_str().unwrap() },
+        uid: entry.pw_uid,
+        gid: entry.pw_gid,
+        gecos: unsafe { CStr::from_ptr(entry.pw_gecos).to_str().unwrap() },
+        dir: unsafe { CStr::from_ptr(entry.pw_dir).to_str().unwrap() },
+        shell: unsafe { CStr::from_ptr(entry.pw_shell).to_str().unwrap() },
+    }
+}
+
+pub struct Pty {
+    child: Child,
+    pub fd: File,
+    token: mio::Token,
+    signals: Signals,
+    signals_token: mio::Token,
+}
+
+impl Pty {
+    /// Resize the pty
+    ///
+    /// Tells the kernel that the window size changed with the new pixel
+    /// dimensions and line/column counts.
+    pub fn resize<T: ToWinsize>(&self, size: &T) {
+        let win = size.to_winsize();
+
+        let res = unsafe { libc::ioctl(self.fd.as_raw_fd(), libc::TIOCSWINSZ, &win as *const _) };
+
+        if res < 0 {
+            die!("ioctl TIOCSWINSZ failed: {}", errno());
+        }
+    }
+}
+
+/// Create a new tty and return a handle to interact with it.
+pub fn new<T: ToWinsize>(
+    config: &Config,
+    options: &Options,
+    size: &T,
+    window_id: Option<usize>,
+) -> Pty {
+    let win_size = size.to_winsize();
+    let mut buf = [0; 1024];
+    let pw = get_pw_entry(&mut buf);
+
+    let (master, slave) = make_pty(win_size);
+
+    let default_shell = if cfg!(target_os = "macos") {
+        let shell_name = pw.shell.rsplit('/').next().unwrap();
+        let argv = vec![String::from("-c"), format!("exec -a -{} {}", shell_name, pw.shell)];
+
+        Shell::new_with_args("/bin/bash", argv)
+    } else {
+        Shell::new(pw.shell)
+    };
+    let shell = config.shell().unwrap_or(&default_shell);
+
+    let initial_command = options.command().unwrap_or(shell);
+
+    let mut builder = Command::new(initial_command.program());
+    for arg in initial_command.args() {
+        builder.arg(arg);
+    }
+
+    // Setup child stdin/stdout/stderr as slave fd of pty
+    // Ownership of fd is transferred to the Stdio structs and will be closed by them at the end of
+    // this scope. (It is not an issue that the fd is closed three times since File::drop ignores
+    // error on libc::close.)
+    builder.stdin(unsafe { Stdio::from_raw_fd(slave) });
+    builder.stderr(unsafe { Stdio::from_raw_fd(slave) });
+    builder.stdout(unsafe { Stdio::from_raw_fd(slave) });
+
+    // Setup shell environment
+    builder.env("LOGNAME", pw.name);
+    builder.env("USER", pw.name);
+    builder.env("SHELL", pw.shell);
+    builder.env("HOME", pw.dir);
+
+    if let Some(window_id) = window_id {
+        builder.env("WINDOWID", format!("{}", window_id));
+    }
+
+    builder.before_exec(move || {
+        // Create a new process group
+        unsafe {
+            let err = libc::setsid();
+            if err == -1 {
+                die!("Failed to set session id: {}", errno());
+            }
+        }
+
+        set_controlling_terminal(slave);
+
+        // No longer need slave/master fds
+        unsafe {
+            libc::close(slave);
+            libc::close(master);
+        }
+
+        unsafe {
+            libc::signal(libc::SIGCHLD, libc::SIG_DFL);
+            libc::signal(libc::SIGHUP, libc::SIG_DFL);
+            libc::signal(libc::SIGINT, libc::SIG_DFL);
+            libc::signal(libc::SIGQUIT, libc::SIG_DFL);
+            libc::signal(libc::SIGTERM, libc::SIG_DFL);
+            libc::signal(libc::SIGALRM, libc::SIG_DFL);
+        }
+        Ok(())
+    });
+
+    // Handle set working directory option
+    if let Some(ref dir) = options.working_dir {
+        builder.current_dir(dir.as_path());
+    }
+
+    // Prepare signal handling before spawning child
+    let signals = Signals::new(&[sighook::SIGCHLD]).expect("error preparing signal handling");
+
+    match builder.spawn() {
+        Ok(child) => {
+            // Remember child PID so other modules can use it
+            PID.store(child.id() as usize, Ordering::Relaxed);
+
+            unsafe {
+                // Maybe this should be done outside of this function so nonblocking
+                // isn't forced upon consumers. Although maybe it should be?
+                set_nonblocking(master);
+            }
+
+            let pty = Pty {
+                child,
+                fd: unsafe { File::from_raw_fd(master) },
+                token: mio::Token::from(0),
+                signals,
+                signals_token: mio::Token::from(0),
+            };
+            pty.resize(size);
+            pty
+        },
+        Err(err) => {
+            die!("Failed to spawn command: {}", err);
+        },
+    }
+}
+
+impl EventedReadWrite for Pty {
+    type Reader = File;
+    type Writer = File;
+
+    #[inline]
+    fn register(
+        &mut self,
+        poll: &mio::Poll,
+        token: &mut dyn Iterator<Item = mio::Token>,
+        interest: mio::Ready,
+        poll_opts: mio::PollOpt,
+    ) -> io::Result<()> {
+        self.token = token.next().unwrap();
+        poll.register(&EventedFd(&self.fd.as_raw_fd()), self.token, interest, poll_opts)?;
+
+        self.signals_token = token.next().unwrap();
+        poll.register(
+            &self.signals,
+            self.signals_token,
+            mio::Ready::readable(),
+            mio::PollOpt::level(),
+        )
+    }
+
+    #[inline]
+    fn reregister(
+        &mut self,
+        poll: &mio::Poll,
+        interest: mio::Ready,
+        poll_opts: mio::PollOpt,
+    ) -> io::Result<()> {
+        poll.reregister(&EventedFd(&self.fd.as_raw_fd()), self.token, interest, poll_opts)?;
+
+        poll.reregister(
+            &self.signals,
+            self.signals_token,
+            mio::Ready::readable(),
+            mio::PollOpt::level(),
+        )
+    }
+
+    #[inline]
+    fn deregister(&mut self, poll: &mio::Poll) -> io::Result<()> {
+        poll.deregister(&EventedFd(&self.fd.as_raw_fd()))?;
+        poll.deregister(&self.signals)
+    }
+
+    #[inline]
+    fn reader(&mut self) -> &mut File {
+        &mut self.fd
+    }
+
+    #[inline]
+    fn read_token(&self) -> mio::Token {
+        self.token
+    }
+
+    #[inline]
+    fn writer(&mut self) -> &mut File {
+        &mut self.fd
+    }
+
+    #[inline]
+    fn write_token(&self) -> mio::Token {
+        self.token
+    }
+}
+
+impl EventedPty for Pty {
+    #[inline]
+    fn next_child_event(&mut self) -> Option<ChildEvent> {
+        self.signals.pending().next().and_then(|signal| {
+            if signal != sighook::SIGCHLD {
+                return None;
+            }
+
+            match self.child.try_wait() {
+                Err(e) => {
+                    error!("Error checking child process termination: {}", e);
+                    None
+                },
+                Ok(None) => None,
+                Ok(_) => Some(ChildEvent::Exited),
+            }
+        })
+    }
+
+    #[inline]
+    fn child_event_token(&self) -> mio::Token {
+        self.signals_token
+    }
+}
+
+pub fn process_should_exit() -> bool {
+    false
+}
+
+/// Types that can produce a `libc::winsize`
+pub trait ToWinsize {
+    /// Get a `libc::winsize`
+    fn to_winsize(&self) -> winsize;
+}
+
+impl<'a> ToWinsize for &'a SizeInfo {
+    fn to_winsize(&self) -> winsize {
+        winsize {
+            ws_row: self.lines().0 as libc::c_ushort,
+            ws_col: self.cols().0 as libc::c_ushort,
+            ws_xpixel: self.width as libc::c_ushort,
+            ws_ypixel: self.height as libc::c_ushort,
+        }
+    }
+}
+
+impl OnResize for i32 {
+    fn on_resize(&mut self, size: &SizeInfo) {
+        let win = size.to_winsize();
+
+        let res = unsafe { libc::ioctl(*self, libc::TIOCSWINSZ, &win as *const _) };
+
+        if res < 0 {
+            die!("ioctl TIOCSWINSZ failed: {}", errno());
+        }
+    }
+}
+
+unsafe fn set_nonblocking(fd: c_int) {
+    use libc::{fcntl, F_GETFL, F_SETFL, O_NONBLOCK};
+
+    let res = fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_NONBLOCK);
+    assert_eq!(res, 0);
+}
+
+#[test]
+fn test_get_pw_entry() {
+    let mut buf: [i8; 1024] = [0; 1024];
+    let _pw = get_pw_entry(&mut buf);
+}