server/rwhod: varlink shenanigans

2026-01-05 16:48:06 +09:00
parent 4f78b1ed1e
commit 0defac7a9f
6 changed files with 448 additions and 12 deletions
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -76,6 +76,48 @@ version = "1.0.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a23eb6b1614318a8071c9b2521f36b424b2c83db5eb3a0fead4a6c0809af6e61"

+[[package]]
+name = "async-broadcast"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "435a87a52755b8f27fcf321ac4f04b2802e337c8c4872923137471ec39c37532"
+dependencies = [
+ "event-listener",
+ "event-listener-strategy",
+ "futures-core",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "async-channel"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "924ed96dd52d1b75e9c1a3e6275715fd320f5f9439fb5a4a11fa51f4221158d2"
+dependencies = [
+ "concurrent-queue",
+ "event-listener-strategy",
+ "futures-core",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "async-io"
+version = "2.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "456b8a8feb6f42d237746d4b3e9a178494627745c3c56c6ea55d92ba50d026fc"
+dependencies = [
+ "autocfg",
+ "cfg-if",
+ "concurrent-queue",
+ "futures-io",
+ "futures-lite",
+ "parking",
+ "polling",
+ "rustix",
+ "slab",
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.5.0"
@@ -183,12 +225,27 @@ version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b05b61dc5112cbb17e4b6cd61790d9845d13888356391624cbe7e41efeac1e75"

+[[package]]
+name = "concurrent-queue"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4ca0197aee26d1ae37445ee532fefce43251d24cc7c166799f4d46817f1d3973"
+dependencies = [
+ "crossbeam-utils",
+]
+
 [[package]]
 name = "core-foundation-sys"
 version = "0.8.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "773648b94d0e5d620f64f280777445740e61fe701025087ec8b57f45c791888b"

+[[package]]
+name = "crossbeam-utils"
+version = "0.8.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0a5c400df2834b80a4c3327b3aad3a4c4cd4de0629063962b03235697506a28"
+
 [[package]]
 name = "deranged"
 version = "0.5.5"
@@ -231,6 +288,33 @@ dependencies = [
 "windows-sys 0.61.2",
 ]

+[[package]]
+name = "event-listener"
+version = "5.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e13b66accf52311f30a0db42147dadea9850cb48cd070028831ae5f5d4b856ab"
+dependencies = [
+ "concurrent-queue",
+ "parking",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "event-listener-strategy"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8be9f3dfaaffdae2972880079a491a1a8bb7cbed0b8dd7a347f668b4150a3b93"
+dependencies = [
+ "event-listener",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "fastrand"
+version = "2.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "37909eebbb50d72f9059c3b6d82c0463f2ff062c9e95845c43a6c9c0355411be"
+
 [[package]]
 name = "find-msvc-tools"
 version = "0.1.6"
@@ -282,6 +366,68 @@ dependencies = [
 "thiserror",
 ]

+[[package]]
+name = "futures-core"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05f29059c0c2090612e8d742178b0580d2dc940c837851ad723096f87af6663e"
+
+[[package]]
+name = "futures-io"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9e5c1b78ca4aae1ac06c48a526a655760685149f0d465d21f37abfe57ce075c6"
+
+[[package]]
+name = "futures-lite"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f78e10609fe0e0b3f4157ffab1876319b5b0db102a2c60dc4626306dc46b44ad"
+dependencies = [
+ "fastrand",
+ "futures-core",
+ "futures-io",
+ "parking",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "futures-macro"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "162ee34ebcb7c64a8abebc059ce0fee27c2262618d7b60ed8faf72fef13c3650"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "futures-sink"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e575fab7d1e0dcb8d0c7bcf9a63ee213816ab51902e6d244a95819acacf1d4f7"
+
+[[package]]
+name = "futures-task"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f90f7dce0722e95104fcb095585910c0977252f286e354b5e3bd38902cd99988"
+
+[[package]]
+name = "futures-util"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9fa08315bb612088cc391249efdc3bc77536f16c91f6cf495e6fbe85b20a4a81"
+dependencies = [
+ "futures-core",
+ "futures-macro",
+ "futures-task",
+ "pin-project-lite",
+ "pin-utils",
+ "slab",
+]
+
 [[package]]
 name = "glob"
 version = "0.3.3"
@@ -294,6 +440,12 @@ version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"

+[[package]]
+name = "hermit-abi"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fc0fef456e4baa96da950455cd02c081ca953b141298e41db3fc7e36b1da849c"
+
 [[package]]
 name = "iana-time-zone"
 version = "0.1.64"
@@ -526,6 +678,12 @@ dependencies = [
 "unicode-width",
 ]

+[[package]]
+name = "parking"
+version = "2.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f38d5652c16fde515bb1ecef450ab0f6a219d619a7274976324d5e377f7dceba"
+
 [[package]]
 name = "phf"
 version = "0.13.1"
@@ -551,6 +709,26 @@ version = "0.2.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3b3cff922bd51709b605d9ead9aa71031d81447142d828eb4a6eba76fe619f9b"

+[[package]]
+name = "pin-utils"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b870d8c151b6f2fb93e84a13146138f05d02ed11c7e7c54f8826aaaf7c9f184"
+
+[[package]]
+name = "polling"
+version = "3.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5d0e4f59085d47d8241c88ead0f274e8a0cb551f3625263c05eb8dd897c34218"
+dependencies = [
+ "cfg-if",
+ "concurrent-queue",
+ "hermit-abi",
+ "pin-project-lite",
+ "rustix",
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "portable-atomic"
 version = "1.13.0"
@@ -615,11 +793,14 @@ dependencies = [
 "bytes",
 "chrono",
 "clap",
+ "futures-util",
 "nix",
+ "serde",
 "tokio",
 "tracing",
 "tracing-subscriber",
 "uucore",
+ "zlink",
 ]

 [[package]]
@@ -647,6 +828,12 @@ version = "1.0.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b39cdef0fa800fc44525c84ccb54a029961a8215f9619753635a9c0d2538d46d"

+[[package]]
+name = "ryu"
+version = "1.0.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a50f4cf475b65d88e057964e0e9bb1f0aa9bbb2036dc65c64596b42932536984"
+
 [[package]]
 name = "self_cell"
 version = "1.2.2"
@@ -683,6 +870,19 @@ dependencies = [
 "syn",
 ]

+[[package]]
+name = "serde_json"
+version = "1.0.148"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3084b546a1dd6289475996f182a22aba973866ea8e8b02c51d9f46b1336a22da"
+dependencies = [
+ "itoa",
+ "memchr",
+ "serde",
+ "serde_core",
+ "zmij",
+]
+
 [[package]]
 name = "sharded-slab"
 version = "0.1.7"
@@ -714,6 +914,12 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "56199f7ddabf13fe5074ce809e7d3f42b42ae711800501b5b16ea82ad029c39d"

+[[package]]
+name = "slab"
+version = "0.4.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7a2ae44ef20feb57a68b23d846850f861394c2e02dc425a50098ae8c90267589"
+
 [[package]]
 name = "smallvec"
 version = "1.15.1"
@@ -836,12 +1042,14 @@ version = "1.49.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "72a2903cd7736441aac9df9d7688bd0ce48edccaadf181c3b90be801e81d3d86"
 dependencies = [
+ "bytes",
 "libc",
 "mio",
 "pin-project-lite",
 "signal-hook-registry",
 "socket2",
 "tokio-macros",
+ "tracing",
 "windows-sys 0.61.2",
 ]

@@ -856,6 +1064,31 @@ dependencies = [
 "syn",
 ]

+[[package]]
+name = "tokio-stream"
+version = "0.1.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32da49809aab5c3bc678af03902d4ccddea2a87d028d86392a4b1560c6906c70"
+dependencies = [
+ "futures-core",
+ "pin-project-lite",
+ "tokio",
+ "tokio-util",
+]
+
+[[package]]
+name = "tokio-util"
+version = "0.7.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9ae9cec805b01e8fc3fd2fe289f89149a9b66dd16786abd8b19cfa7b48cb0098"
+dependencies = [
+ "bytes",
+ "futures-core",
+ "futures-sink",
+ "pin-project-lite",
+ "tokio",
+]
+
 [[package]]
 name = "tracing"
 version = "0.1.44"
@@ -1218,3 +1451,75 @@ dependencies = [
 "serde",
 "zerofrom",
 ]
+
+[[package]]
+name = "zlink"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "04baab6c44f6c5f33dd26dffabe2c6473d9a93a080c3424865df068d4e76f58a"
+dependencies = [
+ "zlink-smol",
+ "zlink-tokio",
+]
+
+[[package]]
+name = "zlink-core"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "487e09febc08bcbac32cee2c26e85779351f711146db0176a3f61a3fea1c955f"
+dependencies = [
+ "futures-util",
+ "itoa",
+ "libc",
+ "pin-project-lite",
+ "rustix",
+ "ryu",
+ "serde",
+ "serde_json",
+ "tracing",
+ "zlink-macros",
+]
+
+[[package]]
+name = "zlink-macros"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6a10a1ed09222634dde2db7055226eafae571389ce57dae3707bd2a76f6dc7b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "zlink-smol"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "72ec157812fcde1a3f45fea27db5a6fa1868ecbf5e11644166ab4caf5e3546dd"
+dependencies = [
+ "async-broadcast",
+ "async-channel",
+ "async-io",
+ "futures-lite",
+ "futures-util",
+ "pin-project-lite",
+ "zlink-core",
+]
+
+[[package]]
+name = "zlink-tokio"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6ab6f490a817bcbbc67d82b22427f1fafd9764da04a6b9499cf73e7ef68f4482"
+dependencies = [
+ "futures-util",
+ "tokio",
+ "tokio-stream",
+ "zlink-core",
+]
+
+[[package]]
+name = "zmij"
+version = "1.0.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "30e0d8dffbae3d840f64bda38e28391faef673a7b5a6017840f2a106c8145868"
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -18,15 +18,17 @@ anyhow = "1.0.100"
 bytes = "1.11.0"
 chrono = { version = "0.4.42", features = ["serde"] }
 clap = { version = "4.5.53", features = ["derive"] }
+futures-util = "0.3.31"
 nix = { version = "0.30.1", features = ["hostname", "net"] }
+serde = { version = "1.0.228", features = ["derive"] }
 tokio = { version = "1.49.0", features = ["macros", "net", "rt-multi-thread", "signal", "sync", "time"] }
 tracing = "0.1.44"
 tracing-subscriber = { version = "0.3.22", features = ["env-filter"] }
 # onc-rpc = "0.3.2"
 # sd-notify = "0.4.5"
-# serde = { version = "1.0.228", features = ["derive"] }
 # serde_json = "1.0.148"
 uucore = { version = "0.5.0", features = ["utmpx"] }
+zlink = { version = "0.2.0", features = ["introspection"] }

 [lib]
 name = "roowho2_lib"
--- a/src/bin/roowhod.rs
+++ b/src/bin/roowhod.rs
@@ -4,8 +4,10 @@ use std::{
    sync::Arc,
 };

+use anyhow::Context;
 use roowho2_lib::server::rwhod::{
-    RWHOD_BROADCAST_PORT, rwhod_packet_receiver_task, rwhod_packet_sender_task,
+    RWHOD_BROADCAST_PORT, rwhod_client_server_task, rwhod_packet_receiver_task,
+    rwhod_packet_sender_task,
 };
 use tokio::sync::RwLock;
 use tracing_subscriber::{EnvFilter, fmt, layer::SubscriberExt, util::SubscriberInitExt};
@@ -18,15 +20,26 @@ async fn main() -> anyhow::Result<()> {
        .init();

    let addr = SocketAddrV4::new(Ipv4Addr::UNSPECIFIED, RWHOD_BROADCAST_PORT);
-    tracing::info!("Binding RWHOD socket to {}", addr);
-    let socket = Arc::new(tokio::net::UdpSocket::bind(addr).await?);
-    socket.set_broadcast(true)?;
+    tracing::debug!("Binding RWHOD socket to {}", addr);
+    let socket = tokio::net::UdpSocket::bind(addr)
+        .await
+        .context("Failed to bind RWHOD UDP socket")
+        .and_then(|socket| {
+            socket.set_broadcast(true)?;
+            Ok(socket)
+        })
+        .context("Failed to enable broadcast on RWHOD UDP socket")
+        .map(Arc::new)?;

    let interfaces = roowho2_lib::server::rwhod::determine_relevant_interfaces()?;
    let sender_task = rwhod_packet_sender_task(socket.clone(), interfaces);

    let status_store = Arc::new(RwLock::new(HashMap::new()));
-    let receiver_task = rwhod_packet_receiver_task(socket.clone(), status_store);
+    let receiver_task = rwhod_packet_receiver_task(socket.clone(), status_store.clone());
+
+    tracing::debug!("Binding RWHOD client-server socket at /run/roowho2/rwhod.socket");
+    let client_server_socket = zlink::unix::bind("/run/roowho2/rwhod.varlink")?;
+    let client_server_task = rwhod_client_server_task(client_server_socket, status_store.clone());

    tokio::select! {
        res = sender_task => {
@@ -39,6 +52,11 @@ async fn main() -> anyhow::Result<()> {
                eprintln!("RWHOD receiver task error: {}", err);
            }
        }
+        res = client_server_task => {
+            if let Err(err) = res {
+                eprintln!("RWHOD client-server task error: {}", err);
+            }
+        }
        _ = tokio::signal::ctrl_c() => {
            println!("Received Ctrl-C, shutting down.");
        }
--- a/src/bin/rwho.rs
+++ b/src/bin/rwho.rs
@@ -1,4 +1,5 @@
 use clap::Parser;
+use roowho2_lib::server::rwhod::RwhodClientProxy;

 /// Check who is logged in on local machines.
 ///
@@ -20,7 +21,18 @@ pub struct Args {
    json: bool,
 }

-fn main() {
-    let _args = Args::parse();
-    unimplemented!()
+#[tokio::main]
+async fn main() {
+    let args = Args::parse();
+
+    let mut conn = zlink::unix::connect("/run/roowho2/rwhod.varlink")
+        .await
+        .expect("Failed to connect to rwhod server");
+
+    let reply = conn
+        .rwho(args.all)
+        .await
+        .expect("Failed to send rwho request");
+
+    println!("{:?}", reply);
 }
--- a/src/proto/rwhod_protocol.rs
+++ b/src/proto/rwhod_protocol.rs
@@ -1,5 +1,6 @@
 use std::array;

+use serde::{Deserialize, Serialize};
 use bytes::{Buf, BufMut, BytesMut};
 use chrono::{DateTime, Duration, Utc};

@@ -239,7 +240,7 @@ pub type LoadAverage = (i32, i32, i32);
 ///
 /// This struct is intended for easier use in Rust code, with proper types and dynamic arrays.
 /// It can be converted to and from the low-level [`Whod`] struct used for network transmission.
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct WhodStatusUpdate {
    // NOTE: there is only one defined packet type, so we just omit it here
    /// Timestamp by sender
@@ -285,7 +286,7 @@ impl WhodStatusUpdate {
 ///
 /// This struct is intended for easier use in Rust code, with proper types.
 /// It can be converted to and from the low-level [`Whoent`] struct used for network transmission.
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct WhodUserEntry {
    /// TTY name (max 8 characters)
    pub tty: String,
--- a/src/server/rwhod.rs
+++ b/src/server/rwhod.rs
@@ -8,7 +8,9 @@ use std::{
 use anyhow::Context;
 use chrono::{DateTime, Duration, Timelike, Utc};
 use nix::{ifaddrs::getifaddrs, net::if_::InterfaceFlags, sys::stat::stat};
+use serde::{Deserialize, Serialize};
 use uucore::utmpx::Utmpx;
+use zlink::{ReplyError, service::MethodReply};

 use crate::proto::{Whod, WhodStatusUpdate, WhodUserEntry};

@@ -229,4 +231,100 @@ pub async fn rwhod_packet_sender_task(
    }
 }

-// TODO: implement protocol for cli - daemon communication
+#[zlink::proxy("no.ntnu.pvv.roowho2.rwhod")]
+pub trait RwhodClientProxy {
+    async fn rwho(
+        &mut self,
+        all: bool,
+    ) -> zlink::Result<Result<Vec<WhodUserEntry>, RwhodClientError>>;
+
+    async fn ruptime(&mut self) -> zlink::Result<Result<Vec<WhodStatusUpdate>, RwhodClientError>>;
+}
+
+#[derive(Debug, Deserialize)]
+#[serde(tag = "method", content = "parameters")]
+pub enum RwhodClientRequest {
+    #[serde(rename = "no.ntnu.pvv.roowho2.rwhod.Rwho")]
+    Rwho {
+        /// Retrieve all users, even those that have been idle for a long time.
+        all: bool,
+    },
+
+    #[serde(rename = "no.ntnu.pvv.roowho2.rwhod.Ruptime")]
+    Ruptime,
+}
+
+#[derive(Debug, Serialize)]
+#[serde(untagged)]
+pub enum RwhodClientResponse {
+    Rwho(Vec<WhodUserEntry>),
+    Ruptime(Vec<WhodStatusUpdate>),
+}
+
+#[derive(Debug, ReplyError)]
+#[zlink(interface = "no.ntnu.pvv.roowho2.rwhod")]
+pub enum RwhodClientError {
+    InvalidRequest,
+}
+
+#[derive(Debug, Clone)]
+pub struct RwhodClientServer {
+    whod_status_store: Arc<tokio::sync::RwLock<HashMap<IpAddr, WhodStatusUpdate>>>,
+}
+
+impl<'a> RwhodClientServer {
+    pub fn new(
+        whod_status_store: Arc<tokio::sync::RwLock<HashMap<IpAddr, WhodStatusUpdate>>>,
+    ) -> Self {
+        Self { whod_status_store }
+    }
+}
+
+impl zlink::Service for RwhodClientServer {
+    type MethodCall<'de> = RwhodClientRequest;
+    type ReplyParams<'se> = RwhodClientResponse;
+    type ReplyStreamParams = ();
+    type ReplyStream = futures_util::stream::Empty<zlink::Reply<()>>;
+    type ReplyError<'se> = RwhodClientError;
+
+    async fn handle<'ser, 'de: 'ser, Sock: zlink::connection::Socket>(
+        &'ser mut self,
+        call: zlink::Call<Self::MethodCall<'de>>,
+        _conn: &mut zlink::Connection<Sock>,
+    ) -> MethodReply<Self::ReplyParams<'ser>, Self::ReplyStream, Self::ReplyError<'ser>> {
+        match call.method() {
+            // TODO: handle 'all' parameter
+            RwhodClientRequest::Rwho { .. } => {
+                let store = self.whod_status_store.read().await;
+                let mut all_user_entries = Vec::new();
+                for status_update in store.values() {
+                    all_user_entries.extend_from_slice(&status_update.users);
+                }
+                MethodReply::Single(Some(RwhodClientResponse::Rwho(all_user_entries)))
+            }
+            RwhodClientRequest::Ruptime => {
+                let store = self.whod_status_store.read().await;
+                let all_status_updates = store.values().cloned().collect();
+                MethodReply::Single(Some(RwhodClientResponse::Ruptime(all_status_updates)))
+            }
+        }
+    }
+}
+
+pub async fn rwhod_client_server_task(
+    socket: zlink::unix::Listener,
+    whod_status_store: Arc<tokio::sync::RwLock<HashMap<IpAddr, WhodStatusUpdate>>>,
+) -> anyhow::Result<()> {
+    let service = RwhodClientServer::new(whod_status_store);
+
+    let server = zlink::Server::new(socket, service);
+
+    tracing::info!("Starting Rwhod client API server");
+
+    server
+        .run()
+        .await
+        .context("Rwhod client API server failed")?;
+
+    Ok(())
+}