Document+check commitment_signed generation success on send_htlc

[rust-lightning] / src / ln / channel.rs

diff --git a/src/ln/channel.rs b/src/ln/channel.rs
index f6e97f12f5cd26b4510b7270f1702397ab1cdaba..e5538a0599d2bdab566c37fe97f649e6672b48eb 100644 (file)
--- a/src/ln/channel.rs
+++ b/src/ln/channel.rs
@@ -2334,6 +2334,7 @@ impl Channel {
        /// This returns an option instead of a pure UpdateAddHTLC as we may be in a state where we are
        /// waiting on the remote peer to send us a revoke_and_ack during which time we cannot add new
        /// HTLCs on the wire or we wouldn't be able to determine what they actually ACK'ed.
+       /// You MUST call send_commitment prior to any other calls on this Channel
        pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: [u8; 32], cltv_expiry: u32, onion_routing_packet: msgs::OnionPacket) -> Result<Option<msgs::UpdateAddHTLC>, HandleError> {
                if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
                        return Err(HandleError{err: "Cannot send HTLC until channel is fully established and we haven't started shutting down", action: None});
@@ -2401,6 +2402,8 @@ impl Channel {
        }
 
        /// Creates a signed commitment transaction to send to the remote peer.
+       /// Always returns a Channel-failing HandleError::action if an immediately-preceding (read: the
+       /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
        pub fn send_commitment(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor), HandleError> {
                if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
                        return Err(HandleError{err: "Cannot create commitment tx until channel is fully established", action: None});