stability improvements

linux/plugins/read_util.cpp

@@ -1,5 +1,10 @@
 /**
  * @brief Utility that will output the value of the position in the shared memory.
+ * 
+ * Return codes:
+ *   0: ok - exited normally (currently not reachable)
+ *   1: error - could not open shared memory
+ *   2: error - failed to mmap shared memory
  */
 
 #include <stdio.h>
@@ -19,11 +24,14 @@
 #include "amtrucks/scssdk_ats.h"
 #include "amtrucks/scssdk_telemetry_ats.h"
 
+#define ERR_COULD_NOT_OPEN_MEMORY 1
+#define ERR_MMAP_FAILED 2
+
 void print_info(telemetry_state_t info) {
     scs_value_dvector_t pos = info.world_position.position;
     int elec = info.electricity.value > 0 ? 1 : 0;
-    fprintf(stdout, "%f,%f,%f;%d\n", pos.x, pos.y, pos.z, elec);
-	fflush(stdout);
+    fprintf(stdout, "INFO %f,%f,%f;%d\n", pos.x, pos.y, pos.z, elec);
+    fflush(stdout);
 }
 
 int main() {
@@ -34,7 +42,7 @@ int main() {
 	int handle = shm_open(shm_name, O_RDONLY, S_IRUSR);
 	if (handle < 0) {
 		fprintf(stderr, "ERR Could not open shared memory\n");
-		return 1;
+		return ERR_COULD_NOT_OPEN_MEMORY;
 	}
 
 	void* mapped_region = mmap(
@@ -48,7 +56,7 @@ int main() {
 
 	if (mapped_region == MAP_FAILED) {
 		fprintf(stderr, "ERR Could not mmap shared memory\n");
-		return 1;
+		return ERR_MMAP_FAILED;
 	}
 
 	telemetry_state_t telemetry;

linux/plugins/uninstall.sh

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+
+rm -f -- ../server/read_util
+
+if [ ! -d "$HOME/.local/share/Steam/steamapps/common/Euro Truck Simulator 2/bin/linux_x64/" ]; then
+    echo "WARN: Could not find ETS2 installation! Please manually move ets2-telemetry-lin.so to your plugins directory."
+    echo "Uninstalled with partial success"
+    exit 1
+else
+    rm -f -- "$HOME/.local/share/Steam/steamapps/common/Euro Truck Simulator 2/bin/linux_x64/plugins/ets2-telemetry-lin.so"
+    rm -f -- "$HOME/.local/share/Steam/steamapps/common/Euro Truck Simulator 2/bin/linux_x86/plugins/ets2-telemetry-lin.so"
+fi
+
+echo "Uninstalled successfully"

linux/server/main.py

@@ -16,18 +16,43 @@ def start_read():
     global last_value, has_elec
     global alive
 
-    read_util = subprocess.Popen(["./read_util"], stdout=subprocess.PIPE, bufsize=1, universal_newlines=True)
-    while read_util.poll() is None and alive:
-        txt = read_util.stdout.readline().strip()
-        if not txt:
-            continue
-
-        parts = txt.split(";")
-        last_value = tuple([float(x) for x in parts[0].split(",")])
-        has_elec[0] = int(parts[1]) > 0
-
-    read_util.stdout.close()
-    read_util.send_signal(signal.SIGKILL)
+    timeout = 1
+
+    while alive:
+        try:
+            read_util = subprocess.Popen(["./read_util"], stdout=subprocess.PIPE, bufsize=1, universal_newlines=True)
+        except Exception as e:
+            print("Couldn't start read util:", e)
+            alive = False
+            break
+
+        while read_util.poll() is None and alive:
+            txt = read_util.stdout.readline().strip()
+            if not txt:
+                continue
+
+            if txt[:4] != "INFO":
+                continue
+
+            # reset timeout
+            timeout = 1
+
+            txt = txt[5:]
+            parts = txt.split(";")
+            last_value = tuple([float(x) for x in parts[0].split(",")])
+            has_elec[0] = int(parts[1]) > 0
+
+        if read_util.returncode == 1:
+            print(f"Your game doesn't seem to be running, trying again in 5 seconds...")
+            time.sleep(5)
+        elif read_util > 0:
+            # Generic error handling
+            print(f"Read util encountered an error, trying again in {timeout} seconds...")
+            time.sleep(timeout)
+            timeout *= 2
+
+        read_util.stdout.close()
+        read_util.send_signal(signal.SIGKILL)
 
 class CustomHandler(SimpleHTTPRequestHandler):
     def __init__(self, *args):
@@ -76,24 +101,38 @@ def do_GET(self):
         else:
             super().do_GET()
 
+    # Comment this out if you want to debug issues - for now this just prevents the
+    # handler cluttering stdout with logs.
+    def log_message(self, format, *args):
+        pass
+
 def run_server():
     global last_value
     global alive
     global httpd
     global PORT
 
-    with socketserver.TCPServer(("", PORT), CustomHandler) as httpd:
-        print("Server open on port", PORT)
-        httpd.serve_forever()
-
-def signal_handler(sig, frame):
+    while alive:
+        try:
+            with socketserver.TCPServer(("", PORT), CustomHandler) as httpd:
+                print(f"Server open on port {PORT}, visit it at: http://localhost:{PORT}/")
+                httpd.serve_forever()
+        except OSError as e:
+            if e.errno == 98:   # Address in use
+                print("That port is already in use (possibly from previous run of this script)")
+                print("Waiting 5 seconds before trying again...")
+                time.sleep(5)
+            else:
+                raise   # reraise
+
+def shutdown(sig=None, frame=None):
     global alive
     global httpd
 
     if not alive:
         return
 
-    print("Interrupted, shutting down")
+    print("Interrupted, shutting down...")
     alive = False
 
     if httpd is not None:
@@ -104,7 +143,7 @@ def signal_handler(sig, frame):
 
     print("Done.")
 
-signal.signal(signal.SIGINT, signal_handler)
+signal.signal(signal.SIGINT, shutdown)
 
 read_thread = threading.Thread(target=start_read)
 server_thread = threading.Thread(target=run_server)