X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Futil%2Fevents.rs;h=1bdbff0333a520e0aced1526272d64bb94e75c40;hb=ecddfe1766f454f1609509a4756201523129235b;hp=599ed2afa68c0b7d2363904959a6daadb9a72c10;hpb=3aa4aa8880642e87cb6e38194b000e6dfab74faa;p=rust-lightning diff --git a/lightning/src/util/events.rs b/lightning/src/util/events.rs index 599ed2af..1bdbff03 100644 --- a/lightning/src/util/events.rs +++ b/lightning/src/util/events.rs @@ -17,13 +17,15 @@ use ln::msgs; use ln::{PaymentPreimage, PaymentHash, PaymentSecret}; use chain::keysinterface::SpendableOutputDescriptor; -use util::ser::{Writeable, Writer, MaybeReadable, Readable}; +use util::ser::{Writeable, Writer, MaybeReadable, Readable, VecReadWrapper, VecWriteWrapper}; use bitcoin::blockdata::script::Script; use bitcoin::secp256k1::key::PublicKey; -use std::time::Duration; +use prelude::*; +use core::time::Duration; +use core::ops::Deref; /// An Event which you should probably take some action in response to. /// @@ -124,7 +126,8 @@ pub enum Event { /// now + 5*time_forwardable). time_forwardable: Duration, }, - /// Used to indicate that an output was generated on-chain which you should know how to spend. + /// Used to indicate that an output which you should know how to spend was confirmed on chain + /// and is now spendable. /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your /// counterparty spending them due to some kind of timeout. Thus, you need to store them /// somewhere and spend them when you create on-chain transactions. @@ -144,14 +147,19 @@ impl Writeable for Event { }, &Event::PaymentReceived { ref payment_hash, ref payment_preimage, ref payment_secret, ref amt, ref user_payment_id } => { 1u8.write(writer)?; - payment_hash.write(writer)?; - payment_preimage.write(writer)?; - payment_secret.write(writer)?; - amt.write(writer)?; - user_payment_id.write(writer)?; + write_tlv_fields!(writer, { + (0, payment_hash, required), + (2, payment_secret, required), + (4, amt, required), + (6, user_payment_id, required), + (8, payment_preimage, option), + }); }, &Event::PaymentSent { ref payment_preimage } => { 2u8.write(writer)?; + write_tlv_fields!(writer, { + (0, payment_preimage, required), + }); payment_preimage.write(writer)?; }, &Event::PaymentFailed { ref payment_hash, ref rejected_by_dest, @@ -161,24 +169,26 @@ impl Writeable for Event { ref error_data, } => { 3u8.write(writer)?; - payment_hash.write(writer)?; - rejected_by_dest.write(writer)?; #[cfg(test)] error_code.write(writer)?; #[cfg(test)] error_data.write(writer)?; + write_tlv_fields!(writer, { + (0, payment_hash, required), + (2, rejected_by_dest, required), + }); }, &Event::PendingHTLCsForwardable { time_forwardable: _ } => { 4u8.write(writer)?; + write_tlv_fields!(writer, {}); // We don't write the time_fordwardable out at all, as we presume when the user // deserializes us at least that much time has elapsed. }, &Event::SpendableOutputs { ref outputs } => { 5u8.write(writer)?; - (outputs.len() as u64).write(writer)?; - for output in outputs.iter() { - output.write(writer)?; - } + write_tlv_fields!(writer, { + (0, VecWriteWrapper(outputs), required), + }); }, } Ok(()) @@ -188,34 +198,83 @@ impl MaybeReadable for Event { fn read(reader: &mut R) -> Result, msgs::DecodeError> { match Readable::read(reader)? { 0u8 => Ok(None), - 1u8 => Ok(Some(Event::PaymentReceived { - payment_hash: Readable::read(reader)?, - payment_preimage: Readable::read(reader)?, - payment_secret: Readable::read(reader)?, - amt: Readable::read(reader)?, - user_payment_id: Readable::read(reader)?, - })), - 2u8 => Ok(Some(Event::PaymentSent { - payment_preimage: Readable::read(reader)?, - })), - 3u8 => Ok(Some(Event::PaymentFailed { - payment_hash: Readable::read(reader)?, - rejected_by_dest: Readable::read(reader)?, + 1u8 => { + let f = || { + let mut payment_hash = PaymentHash([0; 32]); + let mut payment_preimage = None; + let mut payment_secret = PaymentSecret([0; 32]); + let mut amt = 0; + let mut user_payment_id = 0; + read_tlv_fields!(reader, { + (0, payment_hash, required), + (2, payment_secret, required), + (4, amt, required), + (6, user_payment_id, required), + (8, payment_preimage, option), + }); + Ok(Some(Event::PaymentReceived { + payment_hash, + payment_preimage, + payment_secret, + amt, + user_payment_id, + })) + }; + f() + }, + 2u8 => { + let f = || { + let mut payment_preimage = PaymentPreimage([0; 32]); + read_tlv_fields!(reader, { + (0, payment_preimage, required), + }); + Ok(Some(Event::PaymentSent { + payment_preimage, + })) + }; + f() + }, + 3u8 => { + let f = || { #[cfg(test)] - error_code: Readable::read(reader)?, + let error_code = Readable::read(reader)?; #[cfg(test)] - error_data: Readable::read(reader)?, - })), - 4u8 => Ok(Some(Event::PendingHTLCsForwardable { - time_forwardable: Duration::from_secs(0) - })), + let error_data = Readable::read(reader)?; + let mut payment_hash = PaymentHash([0; 32]); + let mut rejected_by_dest = false; + read_tlv_fields!(reader, { + (0, payment_hash, required), + (2, rejected_by_dest, required), + }); + Ok(Some(Event::PaymentFailed { + payment_hash, + rejected_by_dest, + #[cfg(test)] + error_code, + #[cfg(test)] + error_data, + })) + }; + f() + }, + 4u8 => { + let f = || { + read_tlv_fields!(reader, {}); + Ok(Some(Event::PendingHTLCsForwardable { + time_forwardable: Duration::from_secs(0) + })) + }; + f() + }, 5u8 => { - let outputs_len: u64 = Readable::read(reader)?; - let mut outputs = Vec::new(); - for _ in 0..outputs_len { - outputs.push(Readable::read(reader)?); - } - Ok(Some(Event::SpendableOutputs { outputs })) + let f = || { + let mut outputs = VecReadWrapper(Vec::new()); + read_tlv_fields!(reader, { + (0, outputs, required), + }); + Ok(Some(Event::SpendableOutputs { outputs: outputs.0 })) + }; + f() }, _ => Err(msgs::DecodeError::InvalidValue) } @@ -376,9 +435,49 @@ pub trait MessageSendEventsProvider { fn get_and_clear_pending_msg_events(&self) -> Vec; } -/// A trait indicating an object may generate events +/// A trait indicating an object may generate events. +/// +/// Events are processed by passing an [`EventHandler`] to [`process_pending_events`]. +/// +/// # Requirements +/// +/// See [`process_pending_events`] for requirements around event processing. +/// +/// When using this trait, [`process_pending_events`] will call [`handle_event`] for each pending +/// event since the last invocation. The handler must either act upon the event immediately +/// or preserve it for later handling. +/// +/// Note, handlers may call back into the provider and thus deadlocking must be avoided. Be sure to +/// consult the provider's documentation on the implication of processing events and how a handler +/// may safely use the provider (e.g., see [`ChannelManager::process_pending_events`] and +/// [`ChainMonitor::process_pending_events`]). +/// +/// (C-not implementable) As there is likely no reason for a user to implement this trait on their +/// own type(s). +/// +/// [`process_pending_events`]: Self::process_pending_events +/// [`handle_event`]: EventHandler::handle_event +/// [`ChannelManager::process_pending_events`]: crate::ln::channelmanager::ChannelManager#method.process_pending_events +/// [`ChainMonitor::process_pending_events`]: crate::chain::chainmonitor::ChainMonitor#method.process_pending_events pub trait EventsProvider { - /// Gets the list of pending events which were generated by previous actions, clearing the list - /// in the process. - fn get_and_clear_pending_events(&self) -> Vec; + /// Processes any events generated since the last call using the given event handler. + /// + /// Subsequent calls must only process new events. However, handlers must be capable of handling + /// duplicate events across process restarts. This may occur if the provider was recovered from + /// an old state (i.e., it hadn't been successfully persisted after processing pending events). + fn process_pending_events(&self, handler: H) where H::Target: EventHandler; +} + +/// A trait implemented for objects handling events from [`EventsProvider`]. +pub trait EventHandler { + /// Handles the given [`Event`]. + /// + /// See [`EventsProvider`] for details that must be considered when implementing this method. + fn handle_event(&self, event: Event); +} + +impl EventHandler for F where F: Fn(Event) { + fn handle_event(&self, event: Event) { + self(event) + } }