fixed bug in udp loop that could crash loop

src/main.rs

@@ -528,20 +528,28 @@ fn udp_listen(client_mutex: Arc<RwLock<HashMap<u32, Arc<Client>>>>, _room_mutex:
             let client_id_bytes = [buf[1],buf[2],buf[3],buf[4]];
             let client_id = u32::from_be_bytes(client_id_bytes);
 
+            
+
             if t == 0 { //1 byte, 0.  Nothing else.  This is just to establish the udp port, Echos back the same thing sent
                 //connect message, respond back
                 {
                     let clients = client_mutex.read().unwrap();
+                    if clients.contains_key(&client_id){
                         let client = clients.get(&client_id).unwrap();
                         let mut port = client.port.write().unwrap();
                         *port = addr.port(); //set the udp port to send data to
-                    s.send_to(&buf,addr).unwrap(); //echo back
+                        match s.send_to(&buf,addr) {
+                            Ok(_)=>(),
+                            Err(_)=>()
+                        }
+                    }
                 }
                 
                 
             } else if t == 3 { //[3:u8][from:i32][contents:u8array] note that it must fit into the packet of 1024 bytes
                 {
                     let clients = client_mutex.read().unwrap();
+                    if clients.contains_key(&client_id){
                         let client = clients.get(&client_id).unwrap();
                         let room_option = client.room.read().unwrap();
                         let room = room_option.as_ref().unwrap();
@@ -557,10 +565,12 @@ fn udp_listen(client_mutex: Arc<RwLock<HashMap<u32, Arc<Client>>>>, _room_mutex:
                             }
                         }
                     }
+                }
 
             } else if t == 4 { //see above
                 {
                     let clients = client_mutex.read().unwrap();
+                    if clients.contains_key(&client_id){
                         let client = clients.get(&client_id).unwrap();
                         let room_option = client.room.read().unwrap();
                         let room = room_option.as_ref().unwrap();
@@ -577,6 +587,7 @@ fn udp_listen(client_mutex: Arc<RwLock<HashMap<u32, Arc<Client>>>>, _room_mutex:
                             
                         }
                     }
+                }
             } else if t == 5 { //[5:byte][from:i32][group.length():u8][message:u8array]
                 //this one is a little different, because we don't send the group in the message, so we have to formulate another message (like a 3 message)
                 //send a message to a group
@@ -587,6 +598,7 @@ fn udp_listen(client_mutex: Arc<RwLock<HashMap<u32, Arc<Client>>>>, _room_mutex:
                 let (group_name_bytes, message_bytes) = message_vec.split_at(group_name_size as usize);
                 let group_name = String::from_utf8(group_name_bytes.to_vec()).unwrap();
                 let clients = client_mutex.read().unwrap();
+                if clients.contains_key(&client_id){
                     let client = clients.get(&client_id).unwrap();
                     let groups = client.groups.read().unwrap();
                     if groups.contains_key(&group_name) {
@@ -614,6 +626,7 @@ fn udp_listen(client_mutex: Arc<RwLock<HashMap<u32, Arc<Client>>>>, _room_mutex:
                         }
                     }
                 }
+            }
 
             
         }