Add fuzz target testing the total ordering of path selection OrdStrats

fuzz/Cargo.toml

@@ -51,3 +51,9 @@ name = "nlri_ord"
 path = "fuzz_targets/nlri_ord.rs"
 test = false
 doc = false
+
+[[bin]]
+name = "path_selection"
+path = "fuzz_targets/path_selection.rs"
+test = false
+doc = false

fuzz/fuzz_targets/path_selection.rs

@@ -0,0 +1,76 @@
+#![no_main]
+
+use std::cmp::Ordering::*;
+use libfuzzer_sys::fuzz_target;
+use routecore::bgp::{path_attributes::PaMap, path_selection::{OrdRoute, Rfc4271, SkipMed, TiebreakerInfo}};
+
+fn verify_ord<T>(a: &T, b: &T, c: &T)
+    where T: Ord
+{
+    match (a.cmp(b), b.cmp(c)) {
+        // a < b < c
+        (Less, Less) => assert_eq!(a.cmp(c), Less),
+        // a < b == c
+        (Less, Equal) => assert_eq!(a.cmp(c), Less),
+        // a < b > c
+        (Less, Greater) => { } ,
+
+        // a == b == c
+        (Equal, Equal) => {
+            assert_eq!(a.cmp(c), Equal);
+            // Test PartialEq
+            assert!(a == b);
+            assert!(b == c);
+        }
+        // a == b < c
+        (Equal, Less) => assert_eq!(a.cmp(c), Less),
+        // a == b > c
+        (Equal, Greater) => assert_eq!(a.cmp(c), Greater),
+
+        // a > b > c
+        (Greater, Greater) => assert_eq!(a.cmp(c), Greater),
+        // a > b < c
+        (Greater, Less) => { },
+        // a > b == c
+        (Greater, Equal) => assert_eq!(a.cmp(c), Greater),
+    }
+}
+
+// XXX while doing fuzz_target!(|data: &[u8]| ... and then creating an
+// Unstructured from `data` can be useful, the Debug output becomes quite
+// useless. It'll be just a bunch of bytes without any structure.
+// So, something like
+//      fuzz_target!(|data: (OrdRoute, OrdRoute, OrdRoute)| {
+//  has benefits.
+//
+
+//fuzz_target!(|data: &[u8]| {
+fuzz_target!(|data: (PaMap, TiebreakerInfo, PaMap, TiebreakerInfo, PaMap, TiebreakerInfo)| {
+
+    //dbg!(&data);
+
+    let a = match OrdRoute::<()>::try_new(&data.0, data.1) {
+        Ok(r) => r,
+        Err(_) => return,
+    };
+    let b = match OrdRoute::<()>::try_new(&data.2, data.3) {
+        Ok(r) => r,
+        Err(_) => return,
+    };
+    let c = match OrdRoute::<()>::try_new(&data.4, data.5) {
+        Ok(r) => r,
+        Err(_) => return,
+    };
+
+    verify_ord(
+        &OrdRoute::<SkipMed>::from(a),
+        &OrdRoute::<SkipMed>::from(b),
+        &OrdRoute::<SkipMed>::from(c),
+    );
+
+    //verify_ord(
+    //    &OrdRoute::<Rfc4271>::from(a),
+    //    &OrdRoute::<Rfc4271>::from(b),
+    //    &OrdRoute::<Rfc4271>::from(c),
+    //);
+});