Prepare lightning-invoice for export in C

lightning-invoice/src/de.rs

@@ -264,7 +264,7 @@ impl FromStr for SignedRawInvoice {
 				hrp.as_bytes(),
 				&data[..data.len()-104]
 			),
-			signature: Signature::from_base32(&data[data.len()-104..])?,
+			signature: InvoiceSignature::from_base32(&data[data.len()-104..])?,
 		})
 	}
 }
@@ -338,17 +338,17 @@ impl FromBase32 for PositiveTimestamp {
 	}
 }
 
-impl FromBase32 for Signature {
+impl FromBase32 for InvoiceSignature {
 	type Err = ParseError;
 	fn from_base32(signature: &[u5]) -> Result<Self, Self::Err> {
 		if signature.len() != 104 {
-			return Err(ParseError::InvalidSliceLength("Signature::from_base32()".into()));
+			return Err(ParseError::InvalidSliceLength("InvoiceSignature::from_base32()".into()));
 		}
 		let recoverable_signature_bytes = Vec::<u8>::from_base32(signature)?;
 		let signature = &recoverable_signature_bytes[0..64];
 		let recovery_id = RecoveryId::from_i32(recoverable_signature_bytes[64] as i32)?;
 
-		Ok(Signature(RecoverableSignature::from_compact(
+		Ok(InvoiceSignature(RecoverableSignature::from_compact(
 			signature,
 			recovery_id
 		)?))
@@ -999,7 +999,7 @@ mod test {
 		use lightning::ln::features::InvoiceFeatures;
 		use secp256k1::recovery::{RecoveryId, RecoverableSignature};
 		use TaggedField::*;
-		use {SiPrefix, SignedRawInvoice, Signature, RawInvoice, RawHrp, RawDataPart,
+		use {SiPrefix, SignedRawInvoice, InvoiceSignature, RawInvoice, RawHrp, RawDataPart,
 				 Currency, Sha256, PositiveTimestamp};
 
 		// Feature bits 9, 15, and 99 are set.
@@ -1025,7 +1025,7 @@ mod test {
 					hash: [0xb1, 0x96, 0x46, 0xc3, 0xbc, 0x56, 0x76, 0x1d, 0x20, 0x65, 0x6e, 0x0e, 0x32,
 									0xec, 0xd2, 0x69, 0x27, 0xb7, 0x62, 0x6e, 0x2a, 0x8b, 0xe6, 0x97, 0x71, 0x9f,
 									0xf8, 0x7e, 0x44, 0x54, 0x55, 0xb9],
-					signature: Signature(RecoverableSignature::from_compact(
+					signature: InvoiceSignature(RecoverableSignature::from_compact(
 										&[0xd7, 0x90, 0x4c, 0xc4, 0xb7, 0x4a, 0x22, 0x26, 0x9c, 0x68, 0xc1, 0xdf, 0x68,
 											0xa9, 0x6c, 0x21, 0x4d, 0x65, 0x1b, 0x93, 0x76, 0xe9, 0xf1, 0x64, 0xd3, 0x60,
 											0x4d, 0xa4, 0xb7, 0xde, 0xcc, 0xce, 0x0e, 0x82, 0xaa, 0xab, 0x4c, 0x85, 0xd3,
@@ -1045,7 +1045,7 @@ mod test {
 	fn test_raw_signed_invoice_deserialization() {
 		use TaggedField::*;
 		use secp256k1::recovery::{RecoveryId, RecoverableSignature};
-		use {SignedRawInvoice, Signature, RawInvoice, RawHrp, RawDataPart, Currency, Sha256,
+		use {SignedRawInvoice, InvoiceSignature, RawInvoice, RawHrp, RawDataPart, Currency, Sha256,
 			 PositiveTimestamp};
 
 		assert_eq!(
@@ -1078,7 +1078,7 @@ mod test {
 					0x7b, 0x1d, 0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7,
 					0x83, 0x5d, 0xb2, 0xec, 0xd5, 0x18, 0xe1, 0xc9
 				],
-				signature: Signature(RecoverableSignature::from_compact(
+				signature: InvoiceSignature(RecoverableSignature::from_compact(
 					& [
 						0x38u8, 0xec, 0x68, 0x91, 0x34, 0x5e, 0x20, 0x41, 0x45, 0xbe, 0x8a,
 						0x3a, 0x99, 0xde, 0x38, 0xe9, 0x8a, 0x39, 0xd6, 0xa5, 0x69, 0x43,

lightning-invoice/src/lib.rs

@@ -151,6 +151,8 @@ pub fn check_platform() {
 ///  * `D`: exactly one `Description` or `DescriptionHash`
 ///  * `H`: exactly one `PaymentHash`
 ///  * `T`: the timestamp is set
+///
+/// (C-not exported) as we likely need to manually select one set of boolean type parameters.
 #[derive(Eq, PartialEq, Debug, Clone)]
 pub struct InvoiceBuilder<D: tb::Bool, H: tb::Bool, T: tb::Bool> {
 	currency: Currency,
@@ -178,6 +180,9 @@ pub struct Invoice {
 
 /// Represents the description of an invoice which has to be either a directly included string or
 /// a hash of a description provided out of band.
+///
+/// (C-not exported) As we don't have a good way to map the reference lifetimes making this
+/// practically impossible to use safely in languages like C.
 #[derive(Eq, PartialEq, Debug, Clone)]
 pub enum InvoiceDescription<'f> {
 	/// Reference to the directly supplied description in the invoice
@@ -207,7 +212,7 @@ pub struct SignedRawInvoice {
 	hash: [u8; 32],
 
 	/// signature of the payment request
-	signature: Signature,
+	signature: InvoiceSignature,
 }
 
 /// Represents an syntactically correct Invoice for a payment on the lightning network,
@@ -225,6 +230,8 @@ pub struct RawInvoice {
 }
 
 /// Data of the `RawInvoice` that is encoded in the human readable part
+///
+/// (C-not exported) As we don't yet support Option<Enum>
 #[derive(Eq, PartialEq, Debug, Clone)]
 pub struct RawHrp {
 	/// The currency deferred from the 3rd and 4th character of the bech32 transaction
@@ -283,6 +290,9 @@ impl SiPrefix {
 
 	/// Returns all enum variants of `SiPrefix` sorted in descending order of their associated
 	/// multiplier.
+	///
+	/// (C-not exported) As we don't yet support a slice of enums, and also because this function
+	/// isn't the most critical to expose.
 	pub fn values_desc() -> &'static [SiPrefix] {
 		use SiPrefix::*;
 		static VALUES: [SiPrefix; 4] = [Milli, Micro, Nano, Pico];
@@ -381,7 +391,7 @@ pub enum Fallback {
 
 /// Recoverable signature
 #[derive(Eq, PartialEq, Debug, Clone)]
-pub struct Signature(pub RecoverableSignature);
+pub struct InvoiceSignature(pub RecoverableSignature);
 
 /// Private routing information
 ///
@@ -630,7 +640,7 @@ impl SignedRawInvoice {
 	///  1. raw invoice
 	///  2. hash of the raw invoice
 	///  3. signature
-	pub fn into_parts(self) -> (RawInvoice, [u8; 32], Signature) {
+	pub fn into_parts(self) -> (RawInvoice, [u8; 32], InvoiceSignature) {
 		(self.raw_invoice, self.hash, self.signature)
 	}
 
@@ -644,8 +654,8 @@ impl SignedRawInvoice {
 		&self.hash
 	}
 
-	/// Signature for the invoice.
-	pub fn signature(&self) -> &Signature {
+	/// InvoiceSignature for the invoice.
+	pub fn signature(&self) -> &InvoiceSignature {
 		&self.signature
 	}
 
@@ -760,6 +770,9 @@ impl RawInvoice {
 	/// Signs the invoice using the supplied `sign_function`. This function MAY fail with an error
 	/// of type `E`. Since the signature of a `SignedRawInvoice` is not required to be valid there
 	/// are no constraints regarding the validity of the produced signature.
+	///
+	/// (C-not exported) As we don't currently support passing function pointers into methods
+	/// explicitly.
 	pub fn sign<F, E>(self, sign_method: F) -> Result<SignedRawInvoice, E>
 		where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 	{
@@ -771,11 +784,13 @@ impl RawInvoice {
 		Ok(SignedRawInvoice {
 			raw_invoice: self,
 			hash: raw_hash,
-			signature: Signature(signature),
+			signature: InvoiceSignature(signature),
 		})
 	}
 
 	/// Returns an iterator over all tagged fields with known semantics.
+	///
+	/// (C-not exported) As there is not yet a manual mapping for a FilterMap
 	pub fn known_tagged_fields(&self)
 		-> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>>
 	{
@@ -824,6 +839,7 @@ impl RawInvoice {
 		find_extract!(self.known_tagged_fields(), TaggedField::Features(ref x), x)
 	}
 
+	/// (C-not exported) as we don't support Vec<&NonOpaqueType>
 	pub fn fallbacks(&self) -> Vec<&Fallback> {
 		self.known_tagged_fields().filter_map(|tf| match tf {
 			&TaggedField::Fallback(ref f) => Some(f),
@@ -981,6 +997,8 @@ impl Invoice {
 	}
 
 	/// Returns an iterator over all tagged fields of this Invoice.
+	///
+	/// (C-not exported) As there is not yet a manual mapping for a FilterMap
 	pub fn tagged_fields(&self)
 		-> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>> {
 		self.signed_invoice.raw_invoice().known_tagged_fields()
@@ -992,6 +1010,8 @@ impl Invoice {
 	}
 
 	/// Return the description or a hash of it for longer ones
+	///
+	/// (C-not exported) because we don't yet export InvoiceDescription
 	pub fn description(&self) -> InvoiceDescription {
 		if let Some(ref direct) = self.signed_invoice.description() {
 			return InvoiceDescription::Direct(direct);
@@ -1029,11 +1049,13 @@ impl Invoice {
 	}
 
 	/// Returns the invoice's `min_cltv_expiry` time if present
-	pub fn min_final_cltv_expiry(&self) -> Option<&u64> {
-		self.signed_invoice.min_final_cltv_expiry().map(|x| &x.0)
+	pub fn min_final_cltv_expiry(&self) -> Option<u64> {
+		self.signed_invoice.min_final_cltv_expiry().map(|x| x.0)
 	}
 
 	/// Returns a list of all fallback addresses
+	///
+	/// (C-not exported) as we don't support Vec<&NonOpaqueType>
 	pub fn fallbacks(&self) -> Vec<&Fallback> {
 		self.signed_invoice.fallbacks()
 	}
@@ -1192,7 +1214,7 @@ impl Deref for RouteHint {
 	}
 }
 
-impl Deref for Signature {
+impl Deref for InvoiceSignature {
 	type Target = RecoverableSignature;
 
 	fn deref(&self) -> &RecoverableSignature {
@@ -1277,6 +1299,8 @@ impl std::error::Error for SemanticError { }
 
 /// When signing using a fallible method either an user-supplied `SignError` or a `CreationError`
 /// may occur.
+///
+/// (C-not exported) As we don't support unbounded generics
 #[derive(Eq, PartialEq, Debug, Clone)]
 pub enum SignOrCreationError<S> {
 	/// An error occurred during signing
@@ -1354,7 +1378,7 @@ mod test {
 		use secp256k1::Secp256k1;
 		use secp256k1::recovery::{RecoveryId, RecoverableSignature};
 		use secp256k1::key::{SecretKey, PublicKey};
-		use {SignedRawInvoice, Signature, RawInvoice, RawHrp, RawDataPart, Currency, Sha256,
+		use {SignedRawInvoice, InvoiceSignature, RawInvoice, RawHrp, RawDataPart, Currency, Sha256,
 			 PositiveTimestamp};
 
 		let invoice = SignedRawInvoice {
@@ -1383,7 +1407,7 @@ mod test {
 				0x7b, 0x1d, 0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7,
 				0x83, 0x5d, 0xb2, 0xec, 0xd5, 0x18, 0xe1, 0xc9
 			],
-			signature: Signature(RecoverableSignature::from_compact(
+			signature: InvoiceSignature(RecoverableSignature::from_compact(
 				& [
 					0x38u8, 0xec, 0x68, 0x91, 0x34, 0x5e, 0x20, 0x41, 0x45, 0xbe, 0x8a,
 					0x3a, 0x99, 0xde, 0x38, 0xe9, 0x8a, 0x39, 0xd6, 0xa5, 0x69, 0x43,
@@ -1591,7 +1615,7 @@ mod test {
 		);
 		assert_eq!(invoice.payee_pub_key(), Some(&public_key));
 		assert_eq!(invoice.expiry_time(), Duration::from_secs(54321));
-		assert_eq!(invoice.min_final_cltv_expiry(), Some(&144));
+		assert_eq!(invoice.min_final_cltv_expiry(), Some(144));
 		assert_eq!(invoice.fallbacks(), vec![&Fallback::PubKeyHash([0;20])]);
 		assert_eq!(invoice.routes(), vec![&RouteHint(route_1), &RouteHint(route_2)]);
 		assert_eq!(

lightning-invoice/src/ser.rs

@@ -461,7 +461,7 @@ impl ToBase32 for TaggedField {
 	}
 }
 
-impl ToBase32 for Signature {
+impl ToBase32 for InvoiceSignature {
 	fn write_base32<W: WriteBase32>(&self, writer: &mut W) -> Result<(), <W as WriteBase32>::Err> {
 		let mut converter = BytesToBase32::new(writer);
 		let (recovery_id, signature) = self.0.serialize_compact();

lightning/src/chain/chainmonitor.rs

@@ -144,7 +144,6 @@ where C::Target: chain::Filter,
 impl<ChannelSigner: Sign, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
 chain::Listen for ChainMonitor<ChannelSigner, C, T, F, L, P>
 where
-	ChannelSigner: Sign,
 	C::Target: chain::Filter,
 	T::Target: BroadcasterInterface,
 	F::Target: FeeEstimator,
@@ -172,7 +171,6 @@ where
 impl<ChannelSigner: Sign, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
 chain::Confirm for ChainMonitor<ChannelSigner, C, T, F, L, P>
 where
-	ChannelSigner: Sign,
 	C::Target: chain::Filter,
 	T::Target: BroadcasterInterface,
 	F::Target: FeeEstimator,

lightning/src/ln/features.rs

@@ -502,6 +502,7 @@ impl<T: sealed::Context> Features<T> {
 
 	/// Create a Features given a set of flags, in little-endian. This is in reverse byte order from
 	/// most on-the-wire encodings.
+	/// (C-not exported) as we don't support export across multiple T
 	pub fn from_le_bytes(flags: Vec<u8>) -> Features<T> {
 		Features {
 			flags,