Add c_bindings version of RefundBuilder
[rust-lightning] / lightning / src / offers / refund.rs
index 0a95f72511821f33c7b58214e1dcbe4cf2a5647b..f4e9c4a8cc782978273ace12889751e0d1d4921c 100644 (file)
@@ -124,7 +124,18 @@ pub struct RefundBuilder<'a, T: secp256k1::Signing> {
        secp_ctx: Option<&'a Secp256k1<T>>,
 }
 
-impl<'a> RefundBuilder<'a, secp256k1::SignOnly> {
+/// Builds a [`Refund`] for the "offer for money" flow.
+///
+/// See [module-level documentation] for usage.
+///
+/// [module-level documentation]: self
+#[cfg(c_bindings)]
+pub struct RefundMaybeWithDerivedMetadataBuilder<'a> {
+       refund: RefundContents,
+       secp_ctx: Option<&'a Secp256k1<secp256k1::All>>,
+}
+
+macro_rules! refund_explicit_metadata_builder_methods { () => {
        /// Creates a new builder for a refund using the [`Refund::payer_id`] for the public node id to
        /// send to if no [`Refund::paths`] are set. Otherwise, it may be a transient pubkey.
        ///
@@ -155,9 +166,11 @@ impl<'a> RefundBuilder<'a, secp256k1::SignOnly> {
                        secp_ctx: None,
                })
        }
-}
+} }
 
-impl<'a, T: secp256k1::Signing> RefundBuilder<'a, T> {
+macro_rules! refund_builder_methods { (
+       $self: ident, $self_type: ty, $return_type: ty, $return_value: expr, $secp_context: ty $(, $self_mut: tt)?
+) => {
        /// Similar to [`RefundBuilder::new`] except, if [`RefundBuilder::path`] is called, the payer id
        /// is derived from the given [`ExpandedKey`] and nonce. This provides sender privacy by using a
        /// different payer id for each refund, assuming a different nonce is used.  Otherwise, the
@@ -173,7 +186,7 @@ impl<'a, T: secp256k1::Signing> RefundBuilder<'a, T> {
        /// [`ExpandedKey`]: crate::ln::inbound_payment::ExpandedKey
        pub fn deriving_payer_id<ES: Deref>(
                description: String, node_id: PublicKey, expanded_key: &ExpandedKey, entropy_source: ES,
-               secp_ctx: &'a Secp256k1<T>, amount_msats: u64, payment_id: PaymentId
+               secp_ctx: &'a Secp256k1<$secp_context>, amount_msats: u64, payment_id: PaymentId
        ) -> Result<Self, Bolt12SemanticError> where ES::Target: EntropySource {
                if amount_msats > MAX_VALUE_MSAT {
                        return Err(Bolt12SemanticError::InvalidAmount);
@@ -197,17 +210,17 @@ impl<'a, T: secp256k1::Signing> RefundBuilder<'a, T> {
        /// already passed is valid and can be checked for using [`Refund::is_expired`].
        ///
        /// Successive calls to this method will override the previous setting.
-       pub fn absolute_expiry(mut self, absolute_expiry: Duration) -> Self {
-               self.refund.absolute_expiry = Some(absolute_expiry);
-               self
+       pub fn absolute_expiry($($self_mut)* $self: $self_type, absolute_expiry: Duration) -> $return_type {
+               $self.refund.absolute_expiry = Some(absolute_expiry);
+               $return_value
        }
 
        /// Sets the [`Refund::issuer`].
        ///
        /// Successive calls to this method will override the previous setting.
-       pub fn issuer(mut self, issuer: String) -> Self {
-               self.refund.issuer = Some(issuer);
-               self
+       pub fn issuer($($self_mut)* $self: $self_type, issuer: String) -> $return_type {
+               $self.refund.issuer = Some(issuer);
+               $return_value
        }
 
        /// Adds a blinded path to [`Refund::paths`]. Must include at least one path if only connected
@@ -215,26 +228,26 @@ impl<'a, T: secp256k1::Signing> RefundBuilder<'a, T> {
        ///
        /// Successive calls to this method will add another blinded path. Caller is responsible for not
        /// adding duplicate paths.
-       pub fn path(mut self, path: BlindedPath) -> Self {
-               self.refund.paths.get_or_insert_with(Vec::new).push(path);
-               self
+       pub fn path($($self_mut)* $self: $self_type, path: BlindedPath) -> $return_type {
+               $self.refund.paths.get_or_insert_with(Vec::new).push(path);
+               $return_value
        }
 
        /// Sets the [`Refund::chain`] of the given [`Network`] for paying an invoice. If not
        /// called, [`Network::Bitcoin`] is assumed.
        ///
        /// Successive calls to this method will override the previous setting.
-       pub fn chain(self, network: Network) -> Self {
-               self.chain_hash(ChainHash::using_genesis_block(network))
+       pub fn chain($self: $self_type, network: Network) -> $return_type {
+               $self.chain_hash(ChainHash::using_genesis_block(network))
        }
 
        /// Sets the [`Refund::chain`] of the given [`ChainHash`] for paying an invoice. If not called,
        /// [`Network::Bitcoin`] is assumed.
        ///
        /// Successive calls to this method will override the previous setting.
-       pub(crate) fn chain_hash(mut self, chain: ChainHash) -> Self {
-               self.refund.chain = Some(chain);
-               self
+       pub(crate) fn chain_hash($($self_mut)* $self: $self_type, chain: ChainHash) -> $return_type {
+               $self.refund.chain = Some(chain);
+               $return_value
        }
 
        /// Sets [`Refund::quantity`] of items. This is purely for informational purposes. It is useful
@@ -246,60 +259,109 @@ impl<'a, T: secp256k1::Signing> RefundBuilder<'a, T> {
        /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
        /// [`InvoiceRequest::quantity`]: crate::offers::invoice_request::InvoiceRequest::quantity
        /// [`Offer`]: crate::offers::offer::Offer
-       pub fn quantity(mut self, quantity: u64) -> Self {
-               self.refund.quantity = Some(quantity);
-               self
+       pub fn quantity($($self_mut)* $self: $self_type, quantity: u64) -> $return_type {
+               $self.refund.quantity = Some(quantity);
+               $return_value
        }
 
        /// Sets the [`Refund::payer_note`].
        ///
        /// Successive calls to this method will override the previous setting.
-       pub fn payer_note(mut self, payer_note: String) -> Self {
-               self.refund.payer_note = Some(payer_note);
-               self
+       pub fn payer_note($($self_mut)* $self: $self_type, payer_note: String) -> $return_type {
+               $self.refund.payer_note = Some(payer_note);
+               $return_value
        }
 
        /// Builds a [`Refund`] after checking for valid semantics.
-       pub fn build(mut self) -> Result<Refund, Bolt12SemanticError> {
-               if self.refund.chain() == self.refund.implied_chain() {
-                       self.refund.chain = None;
+       pub fn build($($self_mut)* $self: $self_type) -> Result<Refund, Bolt12SemanticError> {
+               if $self.refund.chain() == $self.refund.implied_chain() {
+                       $self.refund.chain = None;
                }
 
                // Create the metadata for stateless verification of a Bolt12Invoice.
-               if self.refund.payer.0.has_derivation_material() {
-                       let mut metadata = core::mem::take(&mut self.refund.payer.0);
+               if $self.refund.payer.0.has_derivation_material() {
+                       let mut metadata = core::mem::take(&mut $self.refund.payer.0);
 
-                       if self.refund.paths.is_none() {
+                       if $self.refund.paths.is_none() {
                                metadata = metadata.without_keys();
                        }
 
-                       let mut tlv_stream = self.refund.as_tlv_stream();
+                       let mut tlv_stream = $self.refund.as_tlv_stream();
                        tlv_stream.0.metadata = None;
                        if metadata.derives_payer_keys() {
                                tlv_stream.2.payer_id = None;
                        }
 
-                       let (derived_metadata, keys) = metadata.derive_from(tlv_stream, self.secp_ctx);
+                       let (derived_metadata, keys) = metadata.derive_from(tlv_stream, $self.secp_ctx);
                        metadata = derived_metadata;
                        if let Some(keys) = keys {
-                               self.refund.payer_id = keys.public_key();
+                               $self.refund.payer_id = keys.public_key();
                        }
 
-                       self.refund.payer.0 = metadata;
+                       $self.refund.payer.0 = metadata;
                }
 
                let mut bytes = Vec::new();
-               self.refund.write(&mut bytes).unwrap();
+               $self.refund.write(&mut bytes).unwrap();
+
+               Ok(Refund {
+                       bytes,
+                       #[cfg(not(c_bindings))]
+                       contents: $self.refund,
+                       #[cfg(c_bindings)]
+                       contents: $self.refund.clone(),
+               })
+       }
+} }
+
+#[cfg(test)]
+macro_rules! refund_builder_test_methods { (
+       $self: ident, $self_type: ty, $return_type: ty, $return_value: expr $(, $self_mut: tt)?
+) => {
+       #[cfg_attr(c_bindings, allow(dead_code))]
+       pub(crate) fn clear_paths($($self_mut)* $self: $self_type) -> $return_type {
+               $self.refund.paths = None;
+               $return_value
+       }
 
-               Ok(Refund { bytes, contents: self.refund })
+       #[cfg_attr(c_bindings, allow(dead_code))]
+       fn features_unchecked($($self_mut)* $self: $self_type, features: InvoiceRequestFeatures) -> $return_type {
+               $self.refund.features = features;
+               $return_value
        }
+} }
+
+impl<'a> RefundBuilder<'a, secp256k1::SignOnly> {
+       refund_explicit_metadata_builder_methods!();
 }
 
-#[cfg(test)]
 impl<'a, T: secp256k1::Signing> RefundBuilder<'a, T> {
-       fn features_unchecked(mut self, features: InvoiceRequestFeatures) -> Self {
-               self.refund.features = features;
-               self
+       refund_builder_methods!(self, Self, Self, self, T, mut);
+
+       #[cfg(test)]
+       refund_builder_test_methods!(self, Self, Self, self, mut);
+}
+
+#[cfg(all(c_bindings, not(test)))]
+impl<'a> RefundMaybeWithDerivedMetadataBuilder<'a> {
+       refund_explicit_metadata_builder_methods!();
+       refund_builder_methods!(self, &mut Self, (), (), secp256k1::All);
+}
+
+#[cfg(all(c_bindings, test))]
+impl<'a> RefundMaybeWithDerivedMetadataBuilder<'a> {
+       refund_explicit_metadata_builder_methods!();
+       refund_builder_methods!(self, &mut Self, &mut Self, self, secp256k1::All);
+       refund_builder_test_methods!(self, &mut Self, &mut Self, self);
+}
+
+#[cfg(c_bindings)]
+impl<'a> From<RefundBuilder<'a, secp256k1::All>>
+for RefundMaybeWithDerivedMetadataBuilder<'a> {
+       fn from(builder: RefundBuilder<'a, secp256k1::All>) -> Self {
+               let RefundBuilder { refund, secp_ctx } = builder;
+
+               Self { refund, secp_ctx }
        }
 }
 
@@ -359,6 +421,11 @@ impl Refund {
                self.contents.is_expired()
        }
 
+       /// Whether the refund has expired given the duration since the Unix epoch.
+       pub fn is_expired_no_std(&self, duration_since_epoch: Duration) -> bool {
+               self.contents.is_expired_no_std(duration_since_epoch)
+       }
+
        /// The issuer of the refund, possibly beginning with `user@domain` or `domain`. Intended to be
        /// displayed to the user but with the caveat that it has not been verified in any way.
        pub fn issuer(&self) -> Option<PrintableString> {
@@ -773,7 +840,15 @@ impl core::fmt::Display for Refund {
 
 #[cfg(test)]
 mod tests {
-       use super::{Refund, RefundBuilder, RefundTlvStreamRef};
+       use super::{Refund, RefundTlvStreamRef};
+       #[cfg(not(c_bindings))]
+       use {
+               super::RefundBuilder,
+       };
+       #[cfg(c_bindings)]
+       use {
+               super::RefundMaybeWithDerivedMetadataBuilder as RefundBuilder,
+       };
 
        use bitcoin::blockdata::constants::ChainHash;
        use bitcoin::network::constants::Network;
@@ -993,6 +1068,7 @@ mod tests {
        fn builds_refund_with_absolute_expiry() {
                let future_expiry = Duration::from_secs(u64::max_value());
                let past_expiry = Duration::from_secs(0);
+               let now = future_expiry - Duration::from_secs(1_000);
 
                let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
                        .absolute_expiry(future_expiry)
@@ -1001,6 +1077,7 @@ mod tests {
                let (_, tlv_stream, _) = refund.as_tlv_stream();
                #[cfg(feature = "std")]
                assert!(!refund.is_expired());
+               assert!(!refund.is_expired_no_std(now));
                assert_eq!(refund.absolute_expiry(), Some(future_expiry));
                assert_eq!(tlv_stream.absolute_expiry, Some(future_expiry.as_secs()));
 
@@ -1012,6 +1089,7 @@ mod tests {
                let (_, tlv_stream, _) = refund.as_tlv_stream();
                #[cfg(feature = "std")]
                assert!(refund.is_expired());
+               assert!(refund.is_expired_no_std(now));
                assert_eq!(refund.absolute_expiry(), Some(past_expiry));
                assert_eq!(tlv_stream.absolute_expiry, Some(past_expiry.as_secs()));
        }