Some refactorings to prepare the switch from calling a lambda function from the forked process to reinvoking the whole process with the job description as json

vuinputd-tests/src/bin/test-keyboard.rs

@@ -13,8 +13,6 @@ use std::mem::{self, size_of, zeroed};
 use std::os::fd::AsRawFd;
 use std::os::raw::{c_char, c_void};
 use std::ptr;
-use std::thread::sleep;
-use std::time::Duration;
 pub use uinput_ioctls::*;
 
 // Constants (same numeric values as in linux headers)

vuinputd/Cargo.toml

@@ -27,3 +27,5 @@ futures = "0.3.31"
 async-io = "2.6.0"
 anyhow = "1.0.100"
 clap = { version = "4", features = ["derive"] }
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"

vuinputd/src/actions/action.rs

@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: MIT
+//
+// Author: Johannes Leupolz <dev@leupolz.eu>
+
+use serde::{Serialize, Deserialize};
+
+#[derive(Serialize,Deserialize)]
+#[serde(tag = "action")]
+pub enum Action {
+    #[serde(rename = "mknod-device")]
+    MknodDevice {
+        path: String,
+        major: u32,
+        minor: u32,
+        mode: u32,
+    },
+
+    #[serde(rename = "announce-via-netlink")]
+    AnnounceViaNetlink {
+        message: String,
+    },
+
+    #[serde(rename = "remove-device")]
+    RemoveDevice {
+        path: String,
+    },
+}

vuinputd/src/actions/handle_action.rs

@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: MIT
+//
+// Author: Johannes Leupolz <dev@leupolz.eu>
+
+use super::action::Action;
+
+pub fn handle_cli_action(json: String) -> i32 {
+    let action: Action = serde_json::from_str(&json)
+        .expect("invalid action JSON");
+    handle_action(action).unwrap_or_else(|err|
+        {
+            panic!("Error handling action: {}",err);
+        });
+    0
+}
+
+fn handle_action(action: Action) -> Result<(), String>  {
+
+    match action {
+        Action::MknodDevice { .. } => {
+            Ok(())
+        }
+        Action::AnnounceViaNetlink { .. } => {
+            Ok(())
+        }
+        Action::RemoveDevice { .. } => {
+            Ok(())
+        }
+    }
+}

vuinputd/src/actions/mod.rs

@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: MIT
+//
+// Author: Johannes Leupolz <dev@leupolz.eu>
+
+pub mod action;
+pub mod handle_action;
+pub mod mknod_input_device;
+pub mod netlink_message;
+pub mod runtime_data;

vuinputd/src/job_engine/closure_job.rs

@@ -5,7 +5,7 @@
 use std::future::Future;
 use std::pin::Pin;
 
-use crate::job_engine::job::{Dispatcher, Job, JobTarget};
+use super::job::{Job, JobTarget};
 
 pub struct ClosureJob {
     desc: String,
@@ -55,34 +55,40 @@ impl Job for ClosureJob {
     }
 }
 
-/// Example usage
-#[test]
-pub fn example() {
-    let mut dispatcher = Dispatcher::new();
+#[cfg(test)]
+mod tests {
+    use super::super::job::{Dispatcher, JobTarget};
+    use super::ClosureJob;
 
-    // Send a Host job
-    dispatcher.dispatch(Box::new(ClosureJob::new(
-        "Host maintenance",
-        JobTarget::Host,
-        false,
-        Box::new(|job: &ClosureJob| {
-            let target = job.target.clone();
-            Box::pin(async move {
-                println!("Running host job on {:?}", target);
-            })
-        }),
-    )));
+    /// Example usage
+    #[test]
+    pub fn example() {
+        let mut dispatcher = Dispatcher::new();
 
-    // Sending a Container job works the same
-    // dispatcher.dispatch(Job::new(JobTarget::Container(ns.clone()), "Container task", false, |target| async move {
-    //     println!("Running container job for {:?}", target);
-    // }));
+        // Send a Host job
+        dispatcher.dispatch(Box::new(ClosureJob::new(
+            "Host maintenance",
+            JobTarget::Host,
+            false,
+            Box::new(|job: &ClosureJob| {
+                let target = job.target.clone();
+                Box::pin(async move {
+                    println!("Running host job on {:?}", target);
+                })
+            }),
+        )));
 
-    //
-    // JOB_DISPATCHER.get().unwrap().lock().unwrap().dispatch(Box::new(ClosureJob::new("Monitor udev events", JobTarget::BackgroundLoop,false,
-    //     Box::new(move |_target| Box::pin(monitor_udev::udev_monitor_loop(cancel_token.clone()))))));
+        // Sending a Container job works the same
+        // dispatcher.dispatch(Job::new(JobTarget::Container(ns.clone()), "Container task", false, |target| async move {
+        //     println!("Running container job for {:?}", target);
+        // }));
 
-    // Allow loops to run briefly before dropping all senders -> graceful shutdown
-    dispatcher.close();
-    dispatcher.wait_until_finished();
+        //
+        // JOB_DISPATCHER.get().unwrap().lock().unwrap().dispatch(Box::new(ClosureJob::new("Monitor udev events", JobTarget::BackgroundLoop,false,
+        //     Box::new(move |_target| Box::pin(monitor_udev::udev_monitor_loop(cancel_token.clone()))))));
+
+        // Allow loops to run briefly before dropping all senders -> graceful shutdown
+        dispatcher.close();
+        dispatcher.wait_until_finished();
+    }
 }

vuinputd/src/jobs/inject_in_container_job.rs

@@ -14,14 +14,7 @@ use async_io::Timer;
 use log::debug;
 
 use crate::{
-    job_engine::job::{Job, JobTarget},
-    jobs::{
-        mknod_input_device::ensure_input_device,
-        monitor_udev_job::EVENT_STORE,
-        netlink_message::send_udev_monitor_message_with_properties,
-        runtime_data::{ensure_udev_structure, read_udev_data, write_udev_data},
-    },
-    process_tools::{await_process, run_in_net_and_mnt_namespace, Pid, RequestingProcess},
+    actions::{mknod_input_device::ensure_input_device, netlink_message::send_udev_monitor_message_with_properties, runtime_data::{ensure_udev_structure, read_udev_data, write_udev_data}}, job_engine::job::{Job, JobTarget}, jobs::monitor_udev_job::EVENT_STORE, process_tools::{Pid, RequestingProcess, await_process, run_in_net_and_mnt_namespace}
 };
 
 #[derive(Clone, Debug, Copy, PartialOrd, PartialEq)]

vuinputd/src/jobs/mod.rs

@@ -3,8 +3,5 @@
 // Author: Johannes Leupolz <dev@leupolz.eu>
 
 pub mod inject_in_container_job;
-pub mod mknod_input_device;
 pub mod monitor_udev_job;
-pub mod netlink_message;
 pub mod remove_from_container_job;
-pub mod runtime_data;

vuinputd/src/jobs/remove_from_container_job.rs

@@ -11,12 +11,7 @@ use std::{
 use log::debug;
 
 use crate::{
-    job_engine::job::{Job, JobTarget},
-    jobs::{
-        mknod_input_device::remove_input_device, monitor_udev_job::EVENT_STORE,
-        netlink_message::send_udev_monitor_message_with_properties, runtime_data::delete_udev_data,
-    },
-    process_tools::{await_process, run_in_net_and_mnt_namespace, Pid, RequestingProcess},
+    actions::{mknod_input_device::remove_input_device, netlink_message::send_udev_monitor_message_with_properties, runtime_data::delete_udev_data}, job_engine::job::{Job, JobTarget}, jobs::monitor_udev_job::EVENT_STORE, process_tools::{Pid, RequestingProcess, await_process, run_in_net_and_mnt_namespace}
 };
 
 #[derive(Clone, Debug, Copy, PartialOrd, PartialEq)]

vuinputd/src/main.rs

@@ -37,6 +37,8 @@ pub mod job_engine;
 use crate::job_engine::{job::*, JOB_DISPATCHER};
 use crate::process_tools::*;
 
+pub mod actions;
+
 pub mod jobs;
 
 use clap::Parser;
@@ -58,9 +60,24 @@ struct Args {
     /// Device name (without /dev/)
     #[arg(long)]
     devname: Option<String>,
+
+    /// Action to execute (JSON encoded). Note that this excludes all other options.
+    #[arg(long, value_name = "JSON")]
+    pub action: Option<String>,
 }
 
 fn validate_args(args: &Args) -> Result<(), String> {
+    // action might only occur alone
+    match (&args.major,&args.minor,&args.devname,&args.action) {
+        (None,None,None,Some(_)) => {},
+        (_,_,_,None)  => {},
+        _ => {
+            return Err(
+                "--action must not be used in combination with any other argument".into(),
+            );
+        }
+    }
+
     // major/minor must appear together
     match (&args.major, &args.minor) {
         (Some(_), Some(_)) | (None, None) => {}
@@ -97,6 +114,11 @@ fn main() -> std::io::Result<()> {
         std::process::exit(2);
     }
 
+    if args.action.is_some() {
+        let error_code=actions::handle_action::handle_cli_action(args.action.unwrap());
+        std::process::exit(error_code);
+    }
+
 
     initialize_vuinput_state();
     VUINPUT_COUNTER.set(AtomicU64::new(3)).expect(