Avoid ref to a `Vec` when accessing custom onion TLVs

The bindings can't easily return a reference to a `Vec`, so we
instead split the implementation into vec/slice depending on the
`c_bindings` flag.

diff --git a/lightning/src/ln/outbound_payment.rs b/lightning/src/ln/outbound_payment.rs
index 1642f28efc7b36dbfa7739bf886ebb58b9eb7c70..b806b138a59092721d10b8e9289d9f0d28df23a0 100644 (file)
--- a/lightning/src/ln/outbound_payment.rs
+++ b/lightning/src/ln/outbound_payment.rs
@@ -594,10 +594,26 @@ impl RecipientOnionFields {
        /// Note that if this field is non-empty, it will contain strictly increasing TLVs, each
        /// represented by a `(u64, Vec<u8>)` for its type number and serialized value respectively.
        /// This is validated when setting this field using [`Self::with_custom_tlvs`].
+       #[cfg(not(c_bindings))]
        pub fn custom_tlvs(&self) -> &Vec<(u64, Vec<u8>)> {
                &self.custom_tlvs
        }
 
+       /// Gets the custom TLVs that will be sent or have been received.
+       ///
+       /// Custom TLVs allow sending extra application-specific data with a payment. They provide
+       /// additional flexibility on top of payment metadata, as while other implementations may
+       /// require `payment_metadata` to reflect metadata provided in an invoice, custom TLVs
+       /// do not have this restriction.
+       ///
+       /// Note that if this field is non-empty, it will contain strictly increasing TLVs, each
+       /// represented by a `(u64, Vec<u8>)` for its type number and serialized value respectively.
+       /// This is validated when setting this field using [`Self::with_custom_tlvs`].
+       #[cfg(c_bindings)]
+       pub fn custom_tlvs(&self) -> Vec<(u64, Vec<u8>)> {
+               self.custom_tlvs.clone()
+       }
+
        /// When we have received some HTLC(s) towards an MPP payment, as we receive further HTLC(s) we
        /// have to make sure that some fields match exactly across the parts. For those that aren't
        /// required to match, if they don't match we should remove them so as to not expose data

diff --git a/lightning/src/ln/payment_tests.rs b/lightning/src/ln/payment_tests.rs
index 72176760243bf25cae3dd3adfcb656a4be6417cd..26ecbb0bd249d116cf8e54f440145c60d1796bbd 100644 (file)
--- a/lightning/src/ln/payment_tests.rs
+++ b/lightning/src/ln/payment_tests.rs
@@ -3781,7 +3781,7 @@ fn test_retry_custom_tlvs() {
                payment_hash, Some(payment_secret), events.pop().unwrap(), true, None).unwrap();
        match payment_claimable {
                Event::PaymentClaimable { onion_fields, .. } => {
-                       assert_eq!(onion_fields.unwrap().custom_tlvs(), &custom_tlvs);
+                       assert_eq!(&onion_fields.unwrap().custom_tlvs()[..], &custom_tlvs[..]);
                },
                _ => panic!("Unexpected event"),
        };