mkfifo: don't delete fifo and fail when --context is used without SELinux/SMACK

src/uu/mkfifo/locales/en-US.ftl

@@ -12,3 +12,6 @@ mkfifo-error-missing-operand = missing operand
 mkfifo-error-cannot-create-fifo = cannot create fifo { $path }: File exists
 mkfifo-error-cannot-set-permissions = cannot set permissions on { $path }: { $error }
 mkfifo-error-non-file-permission = mode must specify only file permission bits
+
+# Warning messages
+mkfifo-warning-context-not-selinux = ignoring --context; it requires an SELinux/SMACK-enabled kernel

src/uu/mkfifo/locales/fr-FR.ftl

@@ -12,3 +12,6 @@ mkfifo-error-missing-operand = opérande manquant
 mkfifo-error-cannot-create-fifo = impossible de créer le fifo { $path } : Le fichier existe
 mkfifo-error-cannot-set-permissions = impossible de définir les permissions sur { $path } : { $error }
 mkfifo-error-non-file-permission = le mode ne doit spécifier que des bits de permission de fichier
+
+# Messages d'avertissement
+mkfifo-warning-context-not-selinux = --context est ignoré ; cela nécessite un noyau avec SELinux/SMACK activé

src/uu/mkfifo/src/mkfifo.rs

@@ -10,6 +10,8 @@ use uucore::display::Quotable;
 use uucore::error::{UResult, USimpleError};
 use uucore::translate;
 
+#[cfg(all(feature = "selinux", any(target_os = "linux", target_os = "android")))]
+use uucore::show_warning;
 use uucore::{format_usage, show};
 
 mod options {
@@ -72,8 +74,12 @@ pub fn uumain(args: impl uucore::Args) -> UResult<()> {
                     if let Err(e) =
                         uucore::selinux::set_selinux_security_context(Path::new(&f), context)
                     {
-                        let _ = std::fs::remove_file(f);
-                        return Err(USimpleError::new(1, e.to_string()));
+                        if matches!(e, uucore::selinux::SeLinuxError::SELinuxNotEnabled) {
+                            show_warning!("{}", translate!("mkfifo-warning-context-not-selinux"));
+                        } else {
+                            let _ = std::fs::remove_file(f);
+                            return Err(USimpleError::new(1, e.to_string()));
+                        }
                     }
                 }
             }

tests/by-util/test_mkfifo.rs

@@ -223,6 +223,31 @@ fn test_mkfifo_selinux_invalid() {
     }
 }
 
+#[test]
+#[cfg(all(
+    feature = "feat_selinux",
+    any(target_os = "linux", target_os = "android")
+))]
+fn test_mkfifo_context_warns_when_kernel_not_enabled() {
+    if uucore::selinux::is_selinux_enabled() {
+        return;
+    }
+
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+    let dest = "test_fifo_context_warning";
+
+    scene
+        .ucmd()
+        .arg("--context=unconfined_u:object_r:user_tmp_t:s0")
+        .arg(dest)
+        .succeeds()
+        .no_stdout()
+        .stderr_contains("ignoring --context");
+
+    assert!(at.is_fifo(dest));
+}
+
 #[test]
 fn test_mkfifo_permission_unchanged_when_failed() {
     use uucore::fs::display_permissions;