PRoces handler.

src/snek/system/terminal.py

@@ -11,10 +11,23 @@ commands = {
 
 class TerminalSession:
     def __init__(self, command):
-        self.master, self.slave = pty.openpty()
+        self.master, self.slave = None,None
+        self.process = None
         self.sockets = []
         self.history = b""
         self.history_size = 1024 * 20
+        self.command = command 
+        self.start_process(self.command)
+
+    def start_process(self, command):
+        if not self.is_running():
+            if self.master:
+                os.close(self.master)
+                os.close(self.slave)
+                self.master = None 
+                self.slave = None
+
+            self.master, self.slave = pty.openpty()
             self.process = subprocess.Popen(
                 command.split(" "),
                 stdin=self.slave,
@@ -24,7 +37,14 @@ class TerminalSession:
                 universal_newlines=True,
             )
 
+    def is_running(self):
+        if not self.process:
+            return False
+        loop = asyncio.get_event_loop()
+        return self.process.poll() is None
+
     async def add_websocket(self, ws):
+        self.start_process(self.command)
         asyncio.create_task(self.read_output(ws))
 
     async def read_output(self, ws):
@@ -52,21 +72,37 @@ class TerminalSession:
                 except:
                     self.sockets.remove(ws)
             except Exception:
+                await self.close()
+                break 
+
+    async def close(self):
         print("Terminating process")
+        if self.process:
             self.process.terminate()
+            self.process = None
+        if self.master:
+            os.close(self.master)
+            os.close(self.slave)
+            self.master = None 
+            self.slave = None 
+
         print("Terminated process")
         for ws in self.sockets:
             try:
                 await ws.close()
             except Exception:
                 pass
-                break
+        self.sockets = []
 
     async def write_input(self, data):
         try:
             data = data.encode()
         except AttributeError:
             pass
+        try:
             await asyncio.get_event_loop().run_in_executor(
                 None, os.write, self.master, data
             )
+        except Exception as ex:
+            print(ex)
+            await self.close()