Solve the freeze in case no runsv to listen to fifo.

01_phase_rust_src/sv/Cargo.toml

@@ -1,8 +1,9 @@
 [package]
 name = "sv"
-version = "0.1.0"
-edition = "2021"
+version = "0.2.0"
+edition = "2024"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+tokio = { version = "1.37.0", features = ["full"] }

01_phase_rust_src/sv/src/status_obj.rs

@@ -8,7 +8,6 @@ use std::io::prelude::*;
 use std::time::SystemTime;
 
 
-
 pub struct StatusObj {
     svname: String, // Service name
     svpath: String, // Service path
@@ -35,15 +34,18 @@ impl StatusObj {
             println!("fail: {}: unable to change to service directory: file does not exist", sv);
             return None
         }
-        let ok_option = Path::new("supervise/ok");
-        if ! ok_option.exists() {
-            println!("warning: {}: unable to open supervise/ok: file does not exist", sv);
+
+        // Check if supervise/control and supervise/ok exists, and if runsv running.
+        let control_exists = misc::check_fifo(sv.clone(), "supervise/ok");
+        if control_exists == false {
+            return None;
+        }
+        let control_exists = misc::check_fifo(sv.clone(), "supervise/control");
+        if control_exists == false {
             return None;
         }
 
 
-        // TODO: check if there is a process reading the pipes. supervise/control and supervise/ok
-        // piste : https://docs.rs/tokio/latest/tokio/net/unix/pipe/struct.OpenOptions.html
         let status_option = fs::OpenOptions::new().read(true).open("supervise/status");
         let mut status = match status_option {
             Ok(file) => file,
@@ -180,4 +182,3 @@ impl StatusObj {
     }
 }
 
-

01_phase_rust_src/sv/src/status_obj/misc.rs

@@ -1,4 +1,9 @@
 
+use std::io::ErrorKind;
+
+use tokio::net::unix::pipe;
+use tokio::runtime::Runtime;
+
 pub fn make_pause_run(pr_int: u8) -> bool {
     if pr_int == 0 {
         return false // run
@@ -72,3 +77,26 @@ pub fn return_u8_in_u64(table: Vec<u8>) -> u64 {
     return r
 }
 
+pub fn check_fifo(sv: String, path: &str) -> bool {
+    // Check if fifo is available. If yes, return true.
+    // If no, return false.
+    let rt = Runtime::new().unwrap();
+    let _guard = rt.enter();
+
+    let sender = pipe::OpenOptions::new().open_sender(path);
+    match sender {
+        Ok(..) => {},
+        Err(e) => match e.kind() {
+            ErrorKind::NotFound => {
+                println!("warning: {sv}: unable to open {path}: file does not exist");
+                return false;
+            },
+            _ => {
+                println!("fail: {sv}: runsv not running");
+                return false;
+            }
+        },
+    };
+
+    return true
+}