Add support for witnesses via a manual mapping

[ldk-c-bindings] / lightning-c-bindings / src / c_types / mod.rs

diff --git a/lightning-c-bindings/src/c_types/mod.rs b/lightning-c-bindings/src/c_types/mod.rs
index 71616375aabfc10a5784650328cf0803f45c24f1..f23f002d05c7ccfe8607ffd5b30eae0c79d0017b 100644 (file)
--- a/lightning-c-bindings/src/c_types/mod.rs
+++ b/lightning-c-bindings/src/c_types/mod.rs
@@ -4,6 +4,7 @@
 pub mod derived;
 
 use bitcoin::Transaction as BitcoinTransaction;
+use bitcoin::Witness as BitcoinWitness;
 use bitcoin::hashes::Hash;
 use bitcoin::secp256k1::PublicKey as SecpPublicKey;
 use bitcoin::secp256k1::SecretKey as SecpSecretKey;
@@ -41,15 +42,44 @@ impl From<core::convert::Infallible> for NotConstructable {
 #[derive(PartialEq, Eq, Copy, Clone)]
 #[allow(non_camel_case_types)]
 #[repr(C)]
-pub struct u5(u8);
+pub struct U5(u8);
 
-impl From<bech32::u5> for u5 {
+impl From<bech32::u5> for U5 {
        fn from(o: bech32::u5) -> Self { Self(o.to_u8()) }
 }
-impl Into<bech32::u5> for u5 {
+impl Into<bech32::u5> for U5 {
        fn into(self) -> bech32::u5 { bech32::u5::try_from_u8(self.0).expect("u5 objects must be in the range 0..32") }
 }
 
+/// Unsigned, 128-bit integer.
+///
+/// Because LLVM implements an incorrect ABI for 128-bit integers, a wrapper type is defined here.
+/// See https://github.com/rust-lang/rust/issues/54341 for more details.
+#[derive(PartialEq, Eq, Copy, Clone)]
+#[allow(non_camel_case_types)]
+#[repr(C)]
+pub struct U128 {
+       /// The 128-bit integer, as 16 little-endian bytes
+       pub le_bytes: [u8; 16],
+}
+
+#[no_mangle]
+/// Gets the 128-bit integer, as 16 little-endian bytes
+pub extern "C" fn U128_le_bytes(val: U128) -> SixteenBytes { SixteenBytes { data: val.le_bytes } }
+#[no_mangle]
+/// Constructs a new U128 from 16 little-endian bytes
+pub extern "C" fn U128_new(le_bytes: SixteenBytes) -> U128 { U128 { le_bytes: le_bytes.data } }
+
+impl From<u128> for U128 {
+       fn from(o: u128) -> Self { Self { le_bytes: o.to_le_bytes() } }
+}
+impl From<&mut u128> for U128 {
+       fn from(o: &mut u128) -> U128 { Self::from(*o) }
+}
+impl Into<u128> for U128 {
+       fn into(self) -> u128 { u128::from_le_bytes(self.le_bytes) }
+}
+
 /// Integer in the range `0..=16`
 #[derive(PartialEq, Eq, Copy, Clone)]
 #[repr(C)]
@@ -431,6 +461,57 @@ impl Clone for Transaction {
 /// Frees the data buffer, if data_is_owned is set and datalen > 0.
 pub extern "C" fn Transaction_free(_res: Transaction) { }
 
+#[repr(C)]
+/// A serialized witness.
+pub struct Witness {
+       /// The serialized transaction data.
+       ///
+       /// This is non-const for your convenience, an object passed to Rust is never written to.
+       pub data: *mut u8,
+       /// The length of the serialized transaction
+       pub datalen: usize,
+       /// Whether the data pointed to by `data` should be freed or not.
+       pub data_is_owned: bool,
+}
+impl Witness {
+       fn from_vec(vec: Vec<u8>) -> Self {
+               let datalen = vec.len();
+               let data = Box::into_raw(vec.into_boxed_slice());
+               Self {
+                       data: unsafe { (*data).as_mut_ptr() },
+                       datalen,
+                       data_is_owned: true,
+               }
+       }
+       pub(crate) fn into_bitcoin(&self) -> BitcoinWitness {
+               ::bitcoin::consensus::encode::deserialize(unsafe { core::slice::from_raw_parts(self.data, self.datalen) }).unwrap()
+       }
+       pub(crate) fn from_bitcoin(btc: &BitcoinWitness) -> Self {
+               let vec = ::bitcoin::consensus::encode::serialize(btc);
+               Self::from_vec(vec)
+       }
+}
+
+impl Drop for Witness {
+       fn drop(&mut self) {
+               if self.data_is_owned && self.datalen != 0 {
+                       let _ = derived::CVec_u8Z { data: self.data as *mut u8, datalen: self.datalen };
+               }
+       }
+}
+impl Clone for Witness {
+       fn clone(&self) -> Self {
+               let sl = unsafe { core::slice::from_raw_parts(self.data, self.datalen) };
+               let mut v = Vec::new();
+               v.extend_from_slice(&sl);
+               Self::from_vec(v)
+       }
+}
+
+#[no_mangle]
+/// Frees the data pointed to by data
+pub extern "C" fn Witness_free(_res: Witness) { }
+
 pub(crate) fn bitcoin_to_C_outpoint(outpoint: ::bitcoin::blockdata::transaction::OutPoint) -> crate::lightning::chain::transaction::OutPoint {
        crate::lightning::chain::transaction::OutPoint_new(ThirtyTwoBytes { data: outpoint.txid.into_inner() }, outpoint.vout.try_into().unwrap())
 }