ping_service/
ping_service.rs

1// Ping service example.
2//
3// You can install and uninstall this service using other example programs.
4// All commands mentioned below shall be executed in Command Prompt with Administrator privileges.
5//
6// Service installation: `install_service.exe`
7// Service uninstallation: `uninstall_service.exe`
8//
9// Start the service: `net start ping_service`
10// Stop the service: `net stop ping_service`
11//
12// Ping server sends a text message to local UDP port 1234 once a second.
13// You can verify that service works by running netcat, i.e: `ncat -ul 1234`.
14
15#[cfg(windows)]
16fn main() -> windows_service::Result<()> {
17    ping_service::run()
18}
19
20#[cfg(not(windows))]
21fn main() {
22    panic!("This program is only intended to run on Windows.");
23}
24
25#[cfg(windows)]
26mod ping_service {
27    use std::{
28        ffi::OsString,
29        net::{IpAddr, SocketAddr, UdpSocket},
30        sync::mpsc,
31        time::Duration,
32    };
33    use windows_service::{
34        define_windows_service,
35        service::{
36            ServiceControl, ServiceControlAccept, ServiceExitCode, ServiceState, ServiceStatus,
37            ServiceType,
38        },
39        service_control_handler::{self, ServiceControlHandlerResult},
40        service_dispatcher, Result,
41    };
42
43    const SERVICE_NAME: &str = "ping_service";
44    const SERVICE_TYPE: ServiceType = ServiceType::OWN_PROCESS;
45
46    const LOOPBACK_ADDR: [u8; 4] = [127, 0, 0, 1];
47    const RECEIVER_PORT: u16 = 1234;
48    const PING_MESSAGE: &str = "ping\n";
49
50    pub fn run() -> Result<()> {
51        // Register generated `ffi_service_main` with the system and start the service, blocking
52        // this thread until the service is stopped.
53        service_dispatcher::start(SERVICE_NAME, ffi_service_main)
54    }
55
56    // Generate the windows service boilerplate.
57    // The boilerplate contains the low-level service entry function (ffi_service_main) that parses
58    // incoming service arguments into Vec<OsString> and passes them to user defined service
59    // entry (my_service_main).
60    define_windows_service!(ffi_service_main, my_service_main);
61
62    // Service entry function which is called on background thread by the system with service
63    // parameters. There is no stdout or stderr at this point so make sure to configure the log
64    // output to file if needed.
65    pub fn my_service_main(_arguments: Vec<OsString>) {
66        if let Err(_e) = run_service() {
67            // Handle the error, by logging or something.
68        }
69    }
70
71    pub fn run_service() -> Result<()> {
72        // Create a channel to be able to poll a stop event from the service worker loop.
73        let (shutdown_tx, shutdown_rx) = mpsc::channel();
74
75        // Define system service event handler that will be receiving service events.
76        let event_handler = move |control_event| -> ServiceControlHandlerResult {
77            match control_event {
78                // Notifies a service to report its current status information to the service
79                // control manager. Always return NoError even if not implemented.
80                ServiceControl::Interrogate => ServiceControlHandlerResult::NoError,
81
82                // Handle stop
83                ServiceControl::Stop => {
84                    shutdown_tx.send(()).unwrap();
85                    ServiceControlHandlerResult::NoError
86                }
87
88                // treat the UserEvent as a stop request
89                ServiceControl::UserEvent(code) => {
90                    if code.to_raw() == 130 {
91                        shutdown_tx.send(()).unwrap();
92                    }
93                    ServiceControlHandlerResult::NoError
94                }
95
96                _ => ServiceControlHandlerResult::NotImplemented,
97            }
98        };
99
100        // Register system service event handler.
101        // The returned status handle should be used to report service status changes to the system.
102        let status_handle = service_control_handler::register(SERVICE_NAME, event_handler)?;
103
104        // Tell the system that service is running
105        status_handle.set_service_status(ServiceStatus {
106            service_type: SERVICE_TYPE,
107            current_state: ServiceState::Running,
108            controls_accepted: ServiceControlAccept::STOP,
109            exit_code: ServiceExitCode::Win32(0),
110            checkpoint: 0,
111            wait_hint: Duration::default(),
112            process_id: None,
113        })?;
114
115        // For demo purposes this service sends a UDP packet once a second.
116        let loopback_ip = IpAddr::from(LOOPBACK_ADDR);
117        let sender_addr = SocketAddr::new(loopback_ip, 0);
118        let receiver_addr = SocketAddr::new(loopback_ip, RECEIVER_PORT);
119        let msg = PING_MESSAGE.as_bytes();
120        let socket = UdpSocket::bind(sender_addr).unwrap();
121
122        loop {
123            let _ = socket.send_to(msg, receiver_addr);
124
125            // Poll shutdown event.
126            match shutdown_rx.recv_timeout(Duration::from_secs(1)) {
127                // Break the loop either upon stop or channel disconnect
128                Ok(_) | Err(mpsc::RecvTimeoutError::Disconnected) => break,
129
130                // Continue work if no events were received within the timeout
131                Err(mpsc::RecvTimeoutError::Timeout) => (),
132            };
133        }
134
135        // Tell the system that service has stopped.
136        status_handle.set_service_status(ServiceStatus {
137            service_type: SERVICE_TYPE,
138            current_state: ServiceState::Stopped,
139            controls_accepted: ServiceControlAccept::empty(),
140            exit_code: ServiceExitCode::Win32(0),
141            checkpoint: 0,
142            wait_hint: Duration::default(),
143            process_id: None,
144        })?;
145
146        Ok(())
147    }
148}
ping_service/ping_service.rs

ping_service/
ping_service.rs
