X-Git-Url: http://git.bitcoin.ninja/index.cgi?p=ldk-c-bindings;a=blobdiff_plain;f=lightning-c-bindings%2Fsrc%2Flightning%2Fln%2Fpeer_handler.rs;h=cad056099405deca31539f1f0c5f87885553eb26;hp=413c144246fc291981b9297cb286a819357e713b;hb=a82e075188fc15a103234832686915c196bfe240;hpb=f0a481f3ab7db33c7cc9cf607f68727b3f89095d diff --git a/lightning-c-bindings/src/lightning/ln/peer_handler.rs b/lightning-c-bindings/src/lightning/ln/peer_handler.rs index 413c144..cad0560 100644 --- a/lightning-c-bindings/src/lightning/ln/peer_handler.rs +++ b/lightning-c-bindings/src/lightning/ln/peer_handler.rs @@ -432,27 +432,37 @@ impl MessageHandler { } } /// A message handler which handles messages specific to channels. Usually this is just a -/// ChannelManager object or a ErroringMessageHandler. +/// [`ChannelManager`] object or an [`ErroringMessageHandler`]. +/// +/// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager #[no_mangle] pub extern "C" fn MessageHandler_get_chan_handler(this_ptr: &MessageHandler) -> *const crate::lightning::ln::msgs::ChannelMessageHandler { let mut inner_val = &mut unsafe { &mut *this_ptr.inner }.chan_handler; inner_val } /// A message handler which handles messages specific to channels. Usually this is just a -/// ChannelManager object or a ErroringMessageHandler. +/// [`ChannelManager`] object or an [`ErroringMessageHandler`]. +/// +/// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager #[no_mangle] pub extern "C" fn MessageHandler_set_chan_handler(this_ptr: &mut MessageHandler, mut val: crate::lightning::ln::msgs::ChannelMessageHandler) { unsafe { &mut *this_ptr.inner }.chan_handler = val; } /// A message handler which handles messages updating our knowledge of the network channel -/// graph. Usually this is just a NetGraphMsgHandlerMonitor object or an IgnoringMessageHandler. +/// graph. Usually this is just a [`NetGraphMsgHandler`] object or an +/// [`IgnoringMessageHandler`]. +/// +/// [`NetGraphMsgHandler`]: crate::routing::network_graph::NetGraphMsgHandler #[no_mangle] pub extern "C" fn MessageHandler_get_route_handler(this_ptr: &MessageHandler) -> *const crate::lightning::ln::msgs::RoutingMessageHandler { let mut inner_val = &mut unsafe { &mut *this_ptr.inner }.route_handler; inner_val } /// A message handler which handles messages updating our knowledge of the network channel -/// graph. Usually this is just a NetGraphMsgHandlerMonitor object or an IgnoringMessageHandler. +/// graph. Usually this is just a [`NetGraphMsgHandler`] object or an +/// [`IgnoringMessageHandler`]. +/// +/// [`NetGraphMsgHandler`]: crate::routing::network_graph::NetGraphMsgHandler #[no_mangle] pub extern "C" fn MessageHandler_set_route_handler(this_ptr: &mut MessageHandler, mut val: crate::lightning::ln::msgs::RoutingMessageHandler) { unsafe { &mut *this_ptr.inner }.route_handler = val; @@ -472,11 +482,12 @@ pub extern "C" fn MessageHandler_new(mut chan_handler_arg: crate::lightning::ln: /// /// For efficiency, Clone should be relatively cheap for this type. /// -/// You probably want to just extend an int and put a file descriptor in a struct and implement -/// send_data. Note that if you are using a higher-level net library that may call close() itself, -/// be careful to ensure you don't have races whereby you might register a new connection with an -/// fd which is the same as a previous one which has yet to be removed via -/// PeerManager::socket_disconnected(). +/// Two descriptors may compare equal (by [`cmp::Eq`] and [`hash::Hash`]) as long as the original +/// has been disconnected, the [`PeerManager`] has been informed of the disconnection (either by it +/// having triggered the disconnection or a call to [`PeerManager::socket_disconnected`]), and no +/// further calls to the [`PeerManager`] related to the original socket occur. This allows you to +/// use a file descriptor for your SocketDescriptor directly, however for simplicity you may wish +/// to simply use another value which is guaranteed to be globally unique instead. #[repr(C)] pub struct SocketDescriptor { /// An opaque pointer which is passed to your function implementations as an argument. @@ -485,40 +496,54 @@ pub struct SocketDescriptor { /// Attempts to send some data from the given slice to the peer. /// /// Returns the amount of data which was sent, possibly 0 if the socket has since disconnected. - /// Note that in the disconnected case, socket_disconnected must still fire and further write - /// attempts may occur until that time. + /// Note that in the disconnected case, [`PeerManager::socket_disconnected`] must still be + /// called and further write attempts may occur until that time. /// - /// If the returned size is smaller than data.len(), a write_available event must - /// trigger the next time more data can be written. Additionally, until the a send_data event - /// completes fully, no further read_events should trigger on the same peer! + /// If the returned size is smaller than `data.len()`, a + /// [`PeerManager::write_buffer_space_avail`] call must be made the next time more data can be + /// written. Additionally, until a `send_data` event completes fully, no further + /// [`PeerManager::read_event`] calls should be made for the same peer! Because this is to + /// prevent denial-of-service issues, you should not read or buffer any data from the socket + /// until then. /// - /// If a read_event on this descriptor had previously returned true (indicating that read - /// events should be paused to prevent DoS in the send buffer), resume_read may be set - /// indicating that read events on this descriptor should resume. A resume_read of false does - /// *not* imply that further read events should be paused. + /// If a [`PeerManager::read_event`] call on this descriptor had previously returned true + /// (indicating that read events should be paused to prevent DoS in the send buffer), + /// `resume_read` may be set indicating that read events on this descriptor should resume. A + /// `resume_read` of false carries no meaning, and should not cause any action. #[must_use] pub send_data: extern "C" fn (this_arg: *mut c_void, data: crate::c_types::u8slice, resume_read: bool) -> usize, - /// Disconnect the socket pointed to by this SocketDescriptor. Once this function returns, no - /// more calls to write_buffer_space_avail, read_event or socket_disconnected may be made with - /// this descriptor. No socket_disconnected call should be generated as a result of this call, - /// though races may occur whereby disconnect_socket is called after a call to - /// socket_disconnected but prior to socket_disconnected returning. + /// Disconnect the socket pointed to by this SocketDescriptor. + /// + /// You do *not* need to call [`PeerManager::socket_disconnected`] with this socket after this + /// call (doing so is a noop). pub disconnect_socket: extern "C" fn (this_arg: *mut c_void), /// Checks if two objects are equal given this object's this_arg pointer and another object. pub eq: extern "C" fn (this_arg: *const c_void, other_arg: &SocketDescriptor) -> bool, /// Calculate a succinct non-cryptographic hash for an object given its this_arg pointer. /// This is used, for example, for inclusion of this object in a hash map. pub hash: extern "C" fn (this_arg: *const c_void) -> u64, - /// Creates a copy of the object pointed to by this_arg, for a copy of this SocketDescriptor. - /// Note that the ultimate copy of the SocketDescriptor will have all function pointers the same as the original. - /// May be NULL if no action needs to be taken, the this_arg pointer will be copied into the new SocketDescriptor. - pub clone: Option *mut c_void>, + /// Called, if set, after this SocketDescriptor has been cloned into a duplicate object. + /// The new SocketDescriptor is provided, and should be mutated as needed to perform a + /// deep copy of the object pointed to by this_arg or avoid any double-freeing. + pub cloned: Option, /// Frees any resources associated with this object given its this_arg pointer. /// Does not need to free the outer struct containing function pointers and may be NULL is no resources need to be freed. pub free: Option, } unsafe impl Send for SocketDescriptor {} unsafe impl Sync for SocketDescriptor {} +#[no_mangle] +pub(crate) extern "C" fn SocketDescriptor_clone_fields(orig: &SocketDescriptor) -> SocketDescriptor { + SocketDescriptor { + this_arg: orig.this_arg, + send_data: Clone::clone(&orig.send_data), + disconnect_socket: Clone::clone(&orig.disconnect_socket), + eq: Clone::clone(&orig.eq), + hash: Clone::clone(&orig.hash), + cloned: Clone::clone(&orig.cloned), + free: Clone::clone(&orig.free), + } +} impl std::cmp::Eq for SocketDescriptor {} impl std::cmp::PartialEq for SocketDescriptor { fn eq(&self, o: &Self) -> bool { (self.eq)(self.this_arg, o) } @@ -529,15 +554,9 @@ impl std::hash::Hash for SocketDescriptor { #[no_mangle] /// Creates a copy of a SocketDescriptor pub extern "C" fn SocketDescriptor_clone(orig: &SocketDescriptor) -> SocketDescriptor { - SocketDescriptor { - this_arg: if let Some(f) = orig.clone { (f)(orig.this_arg) } else { orig.this_arg }, - send_data: Clone::clone(&orig.send_data), - disconnect_socket: Clone::clone(&orig.disconnect_socket), - eq: Clone::clone(&orig.eq), - hash: Clone::clone(&orig.hash), - clone: Clone::clone(&orig.clone), - free: Clone::clone(&orig.free), - } + let mut res = SocketDescriptor_clone_fields(orig); + if let Some(f) = orig.cloned { (f)(&mut res) }; + res } impl Clone for SocketDescriptor { fn clone(&self) -> Self { @@ -666,14 +685,25 @@ pub extern "C" fn PeerHandleError_clone(orig: &PeerHandleError) -> PeerHandleErr use lightning::ln::peer_handler::PeerManager as nativePeerManagerImport; type nativePeerManager = nativePeerManagerImport; -/// A PeerManager manages a set of peers, described by their SocketDescriptor and marshalls socket -/// events into messages which it passes on to its MessageHandlers. +/// A PeerManager manages a set of peers, described by their [`SocketDescriptor`] and marshalls +/// socket events into messages which it passes on to its [`MessageHandler`]. +/// +/// Locks are taken internally, so you must never assume that reentrancy from a +/// [`SocketDescriptor`] call back into [`PeerManager`] methods will not deadlock. +/// +/// Calls to [`read_event`] will decode relevant messages and pass them to the +/// [`ChannelMessageHandler`], likely doing message processing in-line. Thus, the primary form of +/// parallelism in Rust-Lightning is in calls to [`read_event`]. Note, however, that calls to any +/// [`PeerManager`] functions related to the same connection must occur only in serial, making new +/// calls only after previous ones have returned. /// /// Rather than using a plain PeerManager, it is preferable to use either a SimpleArcPeerManager /// a SimpleRefPeerManager, for conciseness. See their documentation for more details, but /// essentially you should default to using a SimpleRefPeerManager, and use a /// SimpleArcPeerManager when you require a PeerManager with a static lifetime, such as when /// you're using lightning-net-tokio. +/// +/// [`read_event`]: PeerManager::read_event #[must_use] #[repr(C)] pub struct PeerManager { @@ -743,8 +773,10 @@ pub extern "C" fn PeerManager_get_peer_node_ids(this_arg: &PeerManager) -> crate /// /// Returns a small number of bytes to send to the remote node (currently always 50). /// -/// Panics if descriptor is duplicative with some other descriptor which has not yet had a -/// socket_disconnected(). +/// Panics if descriptor is duplicative with some other descriptor which has not yet been +/// [`socket_disconnected()`]. +/// +/// [`socket_disconnected()`]: PeerManager::socket_disconnected #[must_use] #[no_mangle] pub extern "C" fn PeerManager_new_outbound_connection(this_arg: &PeerManager, mut their_node_id: crate::c_types::PublicKey, mut descriptor: crate::lightning::ln::peer_handler::SocketDescriptor) -> crate::c_types::derived::CResult_CVec_u8ZPeerHandleErrorZ { @@ -760,8 +792,10 @@ pub extern "C" fn PeerManager_new_outbound_connection(this_arg: &PeerManager, mu /// call socket_disconnected for the new descriptor but must disconnect the connection /// immediately. /// -/// Panics if descriptor is duplicative with some other descriptor which has not yet had -/// socket_disconnected called. +/// Panics if descriptor is duplicative with some other descriptor which has not yet been +/// [`socket_disconnected()`]. +/// +/// [`socket_disconnected()`]: PeerManager::socket_disconnected #[must_use] #[no_mangle] pub extern "C" fn PeerManager_new_inbound_connection(this_arg: &PeerManager, mut descriptor: crate::lightning::ln::peer_handler::SocketDescriptor) -> crate::c_types::derived::CResult_NonePeerHandleErrorZ { @@ -774,12 +808,14 @@ pub extern "C" fn PeerManager_new_inbound_connection(this_arg: &PeerManager, mut /// /// May return an Err to indicate that the connection should be closed. /// -/// Will most likely call send_data on the descriptor passed in (or the descriptor handed into -/// new_*\\_connection) before returning. Thus, be very careful with reentrancy issues! The -/// invariants around calling write_buffer_space_avail in case a write did not fully complete -/// must still hold - be ready to call write_buffer_space_avail again if a write call generated -/// here isn't sufficient! Panics if the descriptor was not previously registered in a -/// new_\\*_connection event. +/// May call [`send_data`] on the descriptor passed in (or an equal descriptor) before +/// returning. Thus, be very careful with reentrancy issues! The invariants around calling +/// [`write_buffer_space_avail`] in case a write did not fully complete must still hold - be +/// ready to call `[write_buffer_space_avail`] again if a write call generated here isn't +/// sufficient! +/// +/// [`send_data`]: SocketDescriptor::send_data +/// [`write_buffer_space_avail`]: PeerManager::write_buffer_space_avail #[must_use] #[no_mangle] pub extern "C" fn PeerManager_write_buffer_space_avail(this_arg: &PeerManager, descriptor: &mut crate::lightning::ln::peer_handler::SocketDescriptor) -> crate::c_types::derived::CResult_NonePeerHandleErrorZ { @@ -792,14 +828,16 @@ pub extern "C" fn PeerManager_write_buffer_space_avail(this_arg: &PeerManager, d /// /// May return an Err to indicate that the connection should be closed. /// -/// Will *not* call back into send_data on any descriptors to avoid reentrancy complexity. -/// Thus, however, you almost certainly want to call process_events() after any read_event to -/// generate send_data calls to handle responses. +/// Will *not* call back into [`send_data`] on any descriptors to avoid reentrancy complexity. +/// Thus, however, you should call [`process_events`] after any `read_event` to generate +/// [`send_data`] calls to handle responses. /// -/// If Ok(true) is returned, further read_events should not be triggered until a send_data call -/// on this file descriptor has resume_read set (preventing DoS issues in the send buffer). +/// If `Ok(true)` is returned, further read_events should not be triggered until a +/// [`send_data`] call on this descriptor has `resume_read` set (preventing DoS issues in the +/// send buffer). /// -/// Panics if the descriptor was not previously registered in a new_*_connection event. +/// [`send_data`]: SocketDescriptor::send_data +/// [`process_events`]: PeerManager::process_events #[must_use] #[no_mangle] pub extern "C" fn PeerManager_read_event(this_arg: &PeerManager, peer_descriptor: &mut crate::lightning::ln::peer_handler::SocketDescriptor, mut data: crate::c_types::u8slice) -> crate::c_types::derived::CResult_boolPeerHandleErrorZ { @@ -810,20 +848,20 @@ pub extern "C" fn PeerManager_read_event(this_arg: &PeerManager, peer_descriptor /// Checks for any events generated by our handlers and processes them. Includes sending most /// response messages as well as messages generated by calls to handler functions directly (eg -/// functions like ChannelManager::process_pending_htlc_forward or send_payment). +/// functions like [`ChannelManager::process_pending_htlc_forwards`] or [`send_payment`]). +/// +/// May call [`send_data`] on [`SocketDescriptor`]s. Thus, be very careful with reentrancy +/// issues! +/// +/// [`send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment +/// [`ChannelManager::process_pending_htlc_forwards`]: crate::ln::channelmanager::ChannelManager::process_pending_htlc_forwards +/// [`send_data`]: SocketDescriptor::send_data #[no_mangle] pub extern "C" fn PeerManager_process_events(this_arg: &PeerManager) { unsafe { &*this_arg.inner }.process_events() } /// Indicates that the given socket descriptor's connection is now closed. -/// -/// This must only be called if the socket has been disconnected by the peer or your own -/// decision to disconnect it and must NOT be called in any case where other parts of this -/// library (eg PeerHandleError, explicit disconnect_socket calls) instruct you to disconnect -/// the peer. -/// -/// Panics if the descriptor was not previously registered in a successful new_*_connection event. #[no_mangle] pub extern "C" fn PeerManager_socket_disconnected(this_arg: &PeerManager, descriptor: &crate::lightning::ln::peer_handler::SocketDescriptor) { unsafe { &*this_arg.inner }.socket_disconnected(descriptor) @@ -831,19 +869,26 @@ pub extern "C" fn PeerManager_socket_disconnected(this_arg: &PeerManager, descri /// Disconnect a peer given its node id. /// -/// Set no_connection_possible to true to prevent any further connection with this peer, +/// Set `no_connection_possible` to true to prevent any further connection with this peer, /// force-closing any channels we have with it. /// -/// If a peer is connected, this will call `disconnect_socket` on the descriptor for the peer, -/// so be careful about reentrancy issues. +/// If a peer is connected, this will call [`disconnect_socket`] on the descriptor for the +/// peer. Thus, be very careful about reentrancy issues. +/// +/// [`disconnect_socket`]: SocketDescriptor::disconnect_socket #[no_mangle] pub extern "C" fn PeerManager_disconnect_by_node_id(this_arg: &PeerManager, mut node_id: crate::c_types::PublicKey, mut no_connection_possible: bool) { unsafe { &*this_arg.inner }.disconnect_by_node_id(node_id.into_rust(), no_connection_possible) } /// This function should be called roughly once every 30 seconds. -/// It will send pings to each peer and disconnect those which did not respond to the last round of pings. -/// Will most likely call send_data on all of the registered descriptors, thus, be very careful with reentrancy issues! +/// It will send pings to each peer and disconnect those which did not respond to the last +/// round of pings. +/// +/// May call [`send_data`] on all [`SocketDescriptor`]s. Thus, be very careful with reentrancy +/// issues! +/// +/// [`send_data`]: SocketDescriptor::send_data #[no_mangle] pub extern "C" fn PeerManager_timer_tick_occurred(this_arg: &PeerManager) { unsafe { &*this_arg.inner }.timer_tick_occurred()