1 files changed, 143 insertions, 0 deletions
diff --git a/alacritty_terminal/src/util.rs b/alacritty_terminal/src/util.rs
new file mode 100644
index 00000000..b8703012
--- /dev/null
+++ b/alacritty_terminal/src/util.rs
@@ -0,0 +1,143 @@
+// 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.
+
+use std::ffi::OsStr;
+use std::process::{Command, Stdio};
+use std::{cmp, io};
+
+#[cfg(not(windows))]
+use std::os::unix::process::CommandExt;
+
+#[cfg(windows)]
+use std::os::windows::process::CommandExt;
+#[cfg(windows)]
+use winapi::um::winbase::{CREATE_NEW_PROCESS_GROUP, CREATE_NO_WINDOW};
+
+/// Threading utilities
+pub mod thread {
+    /// Like `thread::spawn`, but with a `name` argument
+    pub fn spawn_named<F, T, S>(name: S, f: F) -> ::std::thread::JoinHandle<T>
+    where
+        F: FnOnce() -> T,
+        F: Send + 'static,
+        T: Send + 'static,
+        S: Into<String>,
+    {
+        ::std::thread::Builder::new().name(name.into()).spawn(f).expect("thread spawn works")
+    }
+
+    pub use std::thread::*;
+}
+
+pub fn limit<T: Ord>(value: T, min: T, max: T) -> T {
+    cmp::min(cmp::max(value, min), max)
+}
+
+/// Utilities for writing to the
+pub mod fmt {
+    use std::fmt;
+
+    macro_rules! define_colors {
+        ($($(#[$attrs:meta])* pub struct $s:ident => $color:expr;)*) => {
+            $(
+                $(#[$attrs])*
+                pub struct $s<T>(pub T);
+
+                impl<T: fmt::Display> fmt::Display for $s<T> {
+                    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+                        write!(f, concat!("\x1b[", $color, "m{}\x1b[0m"), self.0)
+                    }
+                }
+
+                impl<T: fmt::Debug> fmt::Debug for $s<T> {
+                    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+                        write!(f, concat!("\x1b[", $color, "m{:?}\x1b[0m"), self.0)
+                    }
+                }
+            )*
+        }
+    }
+
+    define_colors! {
+        /// Write a `Display` or `Debug` escaped with Red
+        pub struct Red => "31";
+
+        /// Write a `Display` or `Debug` escaped with Green
+        pub struct Green => "32";
+
+        /// Write a `Display` or `Debug` escaped with Yellow
+        pub struct Yellow => "33";
+    }
+}
+
+#[cfg(not(windows))]
+pub fn start_daemon<I, S>(program: &str, args: I) -> io::Result<()>
+where
+    I: IntoIterator<Item = S>,
+    S: AsRef<OsStr>,
+{
+    Command::new(program)
+        .args(args)
+        .stdin(Stdio::null())
+        .stdout(Stdio::null())
+        .stderr(Stdio::null())
+        .before_exec(|| unsafe {
+            match ::libc::fork() {
+                -1 => return Err(io::Error::last_os_error()),
+                0 => (),
+                _ => ::libc::_exit(0),
+            }
+
+            if ::libc::setsid() == -1 {
+                return Err(io::Error::last_os_error());
+            }
+
+            Ok(())
+        })
+        .spawn()?
+        .wait()
+        .map(|_| ())
+}
+
+#[cfg(windows)]
+pub fn start_daemon<I, S>(program: &str, args: I) -> io::Result<()>
+where
+    I: IntoIterator<Item = S>,
+    S: AsRef<OsStr>,
+{
+    // Setting all the I/O handles to null and setting the
+    // CREATE_NEW_PROCESS_GROUP and CREATE_NO_WINDOW has the effect
+    // that console applications will run without opening a new
+    // console window.
+    Command::new(program)
+        .args(args)
+        .stdin(Stdio::null())
+        .stdout(Stdio::null())
+        .stderr(Stdio::null())
+        .creation_flags(CREATE_NEW_PROCESS_GROUP | CREATE_NO_WINDOW)
+        .spawn()
+        .map(|_| ())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::limit;
+
+    #[test]
+    fn limit_works() {
+        assert_eq!(10, limit(10, 0, 100));
+        assert_eq!(10, limit(5, 10, 100));
+        assert_eq!(100, limit(1000, 10, 100));
+    }
+}