[eclipse-iceoryx#110] Implement Ord and PartialOrd for `ServiceNa…

…me` and `FixedByteString`

doc/release-notes/iceoryx2-unreleased.md

@@ -38,6 +38,7 @@
  * `MessagingPattern` implements `Display` [#64](https://github.com/eclipse-iceoryx/iceoryx2/issues/64)
  * Introduce traits for all ports (`Listen`, `Notify`, `Publish`, `DefaultLoan`, `UninitLoan`, `Subscribe`)
    and for samples (`PayloadMut`, `Payload`) [#69](https://github.com/eclipse-iceoryx/iceoryx2/issues/69)
+ * Implement `Ord` and `PartialOrd` for `FixedSizeByteString` and `ServiceName` [#110](https://github.com/eclipse-iceoryx/iceoryx2/issues/110)
 
 ### API Breaking Changes
 

iceoryx2-bb/container/src/byte_string.rs

@@ -30,6 +30,7 @@
 //! ```
 
 use std::{
+    cmp::Ordering,
     fmt::{Debug, Display},
     hash::Hash,
     mem::MaybeUninit,
@@ -73,6 +74,28 @@ pub struct FixedSizeByteString<const CAPACITY: usize> {
 unsafe impl<const CAPACITY: usize> Send for FixedSizeByteString<CAPACITY> {}
 unsafe impl<const CAPACITY: usize> Sync for FixedSizeByteString<CAPACITY> {}
 
+impl<const CAPACITY: usize, const CAPACITY_OTHER: usize>
+    PartialOrd<FixedSizeByteString<CAPACITY_OTHER>> for FixedSizeByteString<CAPACITY>
+{
+    fn partial_cmp(&self, other: &FixedSizeByteString<CAPACITY_OTHER>) -> Option<Ordering> {
+        for i in 0..std::cmp::min(self.len, other.len) {
+            match unsafe { *self.data[i].as_ptr() }.cmp(unsafe { &*other.data[i].as_ptr() }) {
+                Ordering::Less => return Some(Ordering::Less),
+                Ordering::Greater => return Some(Ordering::Greater),
+                _ => (),
+            }
+        }
+
+        Some(self.len.cmp(&other.len))
+    }
+}
+
+impl<const CAPACITY: usize> Ord for FixedSizeByteString<CAPACITY> {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.partial_cmp(other).unwrap()
+    }
+}
+
 impl<const CAPACITY: usize> Hash for FixedSizeByteString<CAPACITY> {
     fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
         state.write(self.as_bytes())

iceoryx2-bb/container/tests/byte_string_tests.rs

@@ -343,3 +343,14 @@ fn fixed_size_byte_string_strip_suffix_works() {
     assert_that!(sut_clone.strip_suffix(b"msla"), eq false);
     assert_that!(sut_clone, eq sut);
 }
+
+#[test]
+fn fixed_size_byte_ordering_works() {
+    unsafe {
+        assert_that!(Sut::new_unchecked(b"fuubla").cmp(&Sut::new_unchecked(b"fuubla")), eq std::cmp::Ordering::Equal );
+        assert_that!(Sut::new_unchecked(b"fuubla").cmp(&Sut::new_unchecked(b"fuvbla")), eq std::cmp::Ordering::Less );
+        assert_that!(Sut::new_unchecked(b"fuubla").cmp(&Sut::new_unchecked(b"fuubaa")), eq std::cmp::Ordering::Greater );
+        assert_that!(Sut::new_unchecked(b"fuubla").cmp(&Sut::new_unchecked(b"fuubla123")), eq std::cmp::Ordering::Less );
+        assert_that!(Sut::new_unchecked(b"fuubla").cmp(&Sut::new_unchecked(b"fuu")), eq std::cmp::Ordering::Greater );
+    }
+}

iceoryx2/src/service/service_name.rs

@@ -27,7 +27,7 @@ use serde::{de::Visitor, Deserialize, Serialize};
 
 const SERVICE_NAME_LENGTH: usize = 255;
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub struct ServiceName {
     value: iceoryx2_bb_container::byte_string::FixedSizeByteString<SERVICE_NAME_LENGTH>,
 }