Don't allow spaces in usernames

Update PROTOCOL and README
Added -f flag to clean target in frontend Makefile

PROTOCOL.md

@@ -19,9 +19,12 @@ Once a successful socket connection is established, the registration process beg
 
 - The username cannot be one of the five reserved usernames (Server, Error, Info, Notice, TERM)
 - The username cannot be in use by another connected client
+- The username cannot contain spaces
 
 If the username can be used, the server replies with `"K"`. Otherwise, it replies with `"N"`. If registration fails, the server drops the connection immediately. Clients should terminate or give up connecting at this point. A new connection must be made to re-register.
 
+The connecting client must provide a username within 5 seconds. If the server is forced to wait longer than this duration, the connection is dropped.
+
 ## Communication
 
 ### Format

README.md

@@ -7,9 +7,11 @@ The SockTalk protocol is a simple, open-source network communication protocol. C
 Compiling SockTalk requires that the OpenSSL library be installed.
 
 ## Frontend commands
-- "/close" from server side closes server socket.
-- "/disconnect" from client side disconnects from server.
-- "/help" gives a list of commands supported by the server.
+
+- `/close` - from server side closes server socket.
+- `/disconnect` - from client side disconnects from server.
+- `/help` - gives a list of commands supported by the server.
+- `/kick`, `/ban`, `/unban` - prompts for a username and kicks/bans/unbans the user with the given username
 
 ## Legal
 

lib/socktalkserver.cpp

@@ -225,7 +225,7 @@ void SockTalkServer::addHandler(SockTalkClientHandler* ch) {
 }
 
 bool SockTalkServer::isReservedName(const std::string &username) {
-	return username == "Server" || username == "Info" || username == "Error" || username == "Notice" || username == "TERM";
+	return username == "Server" || username == "Info" || username == "Error" || username == "Notice" || username == "TERM" || username.find(" ") != std::string::npos;
 }
 
 bool SockTalkServer::registerName(const std::string &username, const std::string &IP) {

stclient/Makefile

@@ -15,4 +15,4 @@ server:
 	$(CC) $(FLAGS) $(LD) server.cpp $(LIB) $(THREAD) -o server
 
 clean:
-	rm server client
+	rm -f server client