fix: implement node:tty (#20892)

Fixes #21012
Closes https://github.com/denoland/deno/issues/20855
Fixes https://github.com/denoland/deno/issues/20890
Fixes https://github.com/denoland/deno/issues/20611
Fixes https://github.com/denoland/deno/issues/20336
Fixes `create-svelte` from https://github.com/denoland/deno/issues/17248

Fixes more reports here:
- https://github.com/denoland/deno/issues/6529#issuecomment-1432690559
- https://github.com/denoland/deno/issues/6529#issuecomment-1522059006
- https://github.com/denoland/deno/issues/6529#issuecomment-1695803570

1 files changed, 24 insertions, 0 deletions

diff --git a/cli/util/unix.rs b/cli/util/unix.rs
index fd0c94ea6..2fa3c2063 100644
--- a/cli/util/unix.rs
+++ b/cli/util/unix.rs
@@ -43,3 +43,27 @@ pub fn raise_fd_limit() {
     }
   }
 }
+
+pub fn prepare_stdio() {
+  #[cfg(unix)]
+  // SAFETY: Save current state of stdio and restore it when we exit.
+  unsafe {
+    use libc::atexit;
+    use libc::tcgetattr;
+    use libc::tcsetattr;
+    use libc::termios;
+
+    let mut termios = std::mem::zeroed::<termios>();
+    if tcgetattr(libc::STDIN_FILENO, &mut termios) == 0 {
+      static mut ORIG_TERMIOS: Option<termios> = None;
+      ORIG_TERMIOS = Some(termios);
+
+      extern "C" fn reset_stdio() {
+        // SAFETY: Reset the stdio state.
+        unsafe { tcsetattr(libc::STDIN_FILENO, 0, &ORIG_TERMIOS.unwrap()) };
+      }
+
+      atexit(reset_stdio);
+    }
+  }
+}