feat(RuleSet): impl RuleSet for syscalls::Sysno to avoid definining t…

…ypes for single syscalls

src/lib.rs

@@ -220,6 +220,20 @@ impl<T: ?Sized + RuleSet> RuleSet for &T {
     }
 }
 
+impl RuleSet for syscalls::Sysno {
+    fn simple_rules(&self) -> Vec<syscalls::Sysno> {
+        Vec::from([*self])
+    }
+
+    fn conditional_rules(&self) -> HashMap<syscalls::Sysno, Vec<SeccompRule>> {
+        HashMap::new()
+    }
+
+    fn name(&self) -> &'static str {
+        self.name()
+    }
+}
+
 #[must_use]
 /// A struct representing a set of rules to be loaded into a seccomp filter and applied to the
 /// current thread, or all threads in the current process.

tests/sysno.rs

@@ -0,0 +1,21 @@
+use extrasafe::SafetyContext;
+use syscalls::Sysno;
+
+#[test]
+#[should_panic]
+fn hello_void() {
+    SafetyContext::new().apply_to_current_thread().unwrap();
+
+    println!("Hello, World!");
+}
+
+#[test]
+fn hello_world() {
+    SafetyContext::new()
+        .enable(Sysno::write)
+        .unwrap()
+        .apply_to_current_thread()
+        .unwrap();
+
+    println!("Hello, World!");
+}