preventing server from crashing when client crashes; added RPI constant to let the server run without GPIOs

.idea/misc.xml

@@ -1,16 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="CargoProjects">
-    <cargoProject FILE="$PROJECT_DIR$/Cargo.toml" />
-  </component>
   <component name="JavaScriptSettings">
     <option name="languageLevel" value="ES6" />
   </component>
-  <component name="MacroExpansionManager">
-    <option name="directoryName" value="zuWvPryl" />
-  </component>
-  <component name="RustProjectSettings">
-    <option name="toolchainHomeDirectory" value="/usr/bin" />
-    <option name="version" value="2" />
-  </component>
 </project>

Cargo.lock

@@ -1,3 +1,5 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
 [[package]]
 name = "gpio"
 version = "0.4.1"

src/main.rs

@@ -1,10 +1,12 @@
 use std::net::{TcpStream, TcpListener};
 use std::io::prelude::*;
 use std::io::{BufReader, Result};
+//use crate::protocol::Protocol;
 
 mod protocol;
 
 
+
 fn handle_connection(stream: TcpStream, prot: &mut protocol::Protocol) -> Result<()> {
     let mut outstream = stream.try_clone()?;
     let mut reader = BufReader::new(stream);
@@ -13,19 +15,36 @@ fn handle_connection(stream: TcpStream, prot: &mut protocol::Protocol) -> Result
     prot.start();
     write!(outstream,"Hello to 7seg-writer!\n").expect("could not write to TCP Stream!");
     while prot.is_running() {
-        let len = reader.read_line(&mut text).expect("Reading line from client failed!");
+        let len = match reader.read_line(&mut text) {
+            Ok(len) => len,
+            Err(_) => {
+                println!("Reading line from client failed!");
+                0
+            },
+        };
+
         if len == 0 {
             break;
         }
         println!("read: {}", text);
         match prot.parse(&text) {
             Ok(response) => {
-                writeln!(outstream,"{}",response).expect("could not write to TCP Stream!");
+                match writeln!(outstream,"{}",response) {
-                //stream.write_line(response.as_bytes());
+                    Ok(_) => (),
+                    Err(_) => {
+                        prot.stop();
+                        println!("Write to TCP Stream failed")
+                    },
+                }
             },
             Err(e) => {
-                writeln!(outstream,"{}",e).expect("could not write to TCP Stream!");
+                match writeln!(outstream,"{}",e) {
-                //stream.write_line(e.as_bytes());
+                    Ok(_) => (),
+                    Err(_) => {
+                        prot.stop();
+                        println!("Write to TCP Stream failed")
+                    },
+                }
             }
         }
         text = String::from("");
@@ -39,7 +58,9 @@ fn main() -> Result<()> {
     let listener = TcpListener::bind(address).expect("could not start server");
     let mut prot = protocol::Protocol::new();
     println!("Initialize GPIO");
+    if protocol::RPI {
         prot.init();
+    }
     println!("Ready");
     // accept connections and get a TcpStream
     for connection in listener.incoming() {

src/protocol.rs

@@ -2,6 +2,8 @@ extern crate gpio;
 
 use gpio::GpioOut;
 
+pub static RPI: bool = true;
+
 struct Segment {
     nextval: bool,
     port: gpio::sysfs::SysFsGpioOutput,
@@ -26,7 +28,6 @@ impl Segment {
     }
 }
 
-
 pub struct Protocol {
     segments: Vec<Segment>,
     running: bool,
@@ -49,13 +50,16 @@ impl Protocol {
         self.segments.push(Segment::new(21));
         self.segments.push(Segment::new(20));
         self.segments.push(Segment::new(16));
-
     }
 
     pub fn start(&mut self) {
         self.running = true;
     }
 
+    pub fn stop(&mut self) {
+        self.running = false;
+    }
+
     pub fn is_running(&self) -> bool{
         self.running
     }
@@ -87,18 +91,25 @@ impl Protocol {
                     "off" => false,
                     _ => return Err("ERR no value for segment")
                 };
+                if RPI {
                     self.segments[index].set_nextval(value);
+                } else {
+                    println!("segment {} = {}", index, value);
+                }
             }
             "display" => {
                 //show the saved state on the display
 
-                for i in 0 .. 8 {
+                if RPI {
+                    for i in 0..8 {
                         match self.segments[i].show() {
                             Ok(_) => (),
                             Err(e) => println!("{}", e),
-
                         }
                     }
+                } else {
+                    println!("showing segments")
+                }
                 println!();
             }
             "exit" => {