Refactor common::is_console_session

- Use nix::unistd::ttyname
- Simplify logic with pattern matching

Closes #12179

Cargo.toml

@@ -33,6 +33,7 @@ nix = { version = "0.30.1", default-features = false, features = [
     "inotify",
     "resource",
     "fs",
+    "term",
 ] }
 num-traits = "0.2.19"
 once_cell = "1.19.0"

src/common.rs

@@ -1833,27 +1833,20 @@ pub fn is_console_session() -> bool {
     static IS_CONSOLE_SESSION: OnceCell<bool> = OnceCell::new();
     // TODO(terminal-workaround)
     *IS_CONSOLE_SESSION.get_or_init(|| {
-        const PATH_MAX: usize = libc::PATH_MAX as usize;
-        let mut tty_name = [0u8; PATH_MAX];
-        unsafe {
-            if libc::ttyname_r(STDIN_FILENO, tty_name.as_mut_ptr().cast(), tty_name.len()) != 0 {
-                return false;
-            }
-        }
-        // Check if the tty matches /dev/(console|dcons|tty[uv\d])
-        const LEN: usize = b"/dev/tty".len();
-        (
-        (
-            tty_name.starts_with(b"/dev/tty") &&
-                ([b'u', b'v'].contains(&tty_name[LEN]) || tty_name[LEN].is_ascii_digit())
-        ) ||
-        tty_name.starts_with(b"/dev/dcons\0") ||
-        tty_name.starts_with(b"/dev/console\0"))
-        // and that $TERM is simple, e.g. `xterm` or `vt100`, not `xterm-something` or `sun-color`.
-        && match env::var_os("TERM") {
-            Some(term) => !term.as_bytes().contains(&b'-'),
-            None => true,
-        }
+        nix::unistd::ttyname(unsafe { std::os::fd::BorrowedFd::borrow_raw(STDIN_FILENO) })
+            .is_ok_and(|buf| {
+                // Check if the tty matches /dev/(console|dcons|tty[uv\d])
+                let is_console_tty = match buf.as_os_str().as_bytes() {
+                    b"/dev/console" => true,
+                    b"/dev/dcons" => true,
+                    bytes => bytes.strip_prefix(b"/dev/tty").is_some_and(|rest| {
+                        matches!(rest.first(), Some(b'u' | b'v' | b'0'..=b'9'))
+                    }),
+                };
+
+                // and that $TERM is simple, e.g. `xterm` or `vt100`, not `xterm-something` or `sun-color`.
+                is_console_tty && env::var_os("TERM").is_none_or(|t| !t.as_bytes().contains(&b'-'))
+            })
     })
 }