LuaSocket and Telnet

Questions
1

I saw the topic on LuaSockets in the Codea forums at https://codea.io/talk/discussion/6344/luasocket-questions/p1 and started expirementing with some code. I learned a lot from this discussion and the example code, so I went on to make my own program using LuaSocket. I tested this program using my iPad and my brother’s iPad and it worked fine! My problem is that when I used Telnet on my PC (Yes, I have it enabled, so that’s not the prob), it won’t connect. Anyone know what I’m doing wrong?

Here’s what I’m doing

Command Prompt:
I type “telnet 192.168.0.# 5400”

iPad:
I set the IP to 192.168.0.# and the port to 5400

2

Can you post the code you used? I’d guess it would be a problem with the code, or perhaps with a firewall. Never experienced Windows blocking Telnet though, but I’d have to see the code to be sure. Also, how are you “setting” the iPad’s IP address? Are you giving it a static IP?

3

I guess I should reword that correctly. The iPad gives me an IP address.
Here’s the code:

-- Chat Room

-- Use this function to perform your initial setup
function setup()
    msgs = {}
    msg = ""
    scrolling = false
    parameter.text("Username", "Guest")
    supportedOrientations(LANDSCAPE_ANY)
    
    local connectionMade = function()
        output.clear()
        parameter.clear()
        print("Connected!")
    end

    multihandler = Multiuser(receiveData, connectionMade)

    parameter.action("Host Room", function()
        multihandler:hostRoom()
    end)

    parameter.action("Search for and Join Room", function()
        multihandler:findRoom()
    end)

    parameter.action("Join Room", function()
        if other_ip then
            multihandler:joinRoom(other_ip, other_port)
        else
            parameter.text("other_ip", "")
            parameter.text("other_port", "")

            print("Fill in the host's ip and port, then click Join Room again")
        end
    end)
end

-- This function gets called once every frame
function draw()
    multihandler:update()
    background(52, 52, 52, 255)
    if multihandler.connected then
        fill(255, 255, 255, 255)
        rect(0, 0, WIDTH, HEIGHT/2+36)
        fill(0, 0, 0, 255)
        text(msg, WIDTH/2, HEIGHT/2+25)
        showKeyboard()
        if (#msgs > 10) then
            for i=1, 10 do
                msgs[i] = msgs[i+1]
            end
            msgs[11] = nil
        end
        fill(255, 255, 255, 255)
        if (#msgs < 11) then
            for i = 1, #msgs do
                text(msgs[i], WIDTH/2, HEIGHT-(20*i))
            end
        end
    else
        fill(255, 94, 0, 255)
        text("RULES OF THE CHAT ROOM", WIDTH/2, 500)
        text("1.) Be nice. Cyberbullying is a crime.", WIDTH/2, 450)
        text("2.) Spamming can hurt the socket connection. You will be kicked from the chat if you do so.", WIDTH/2, 400)
        text("3.) Sending nil (blank) messages can also hurt the socket connection", WIDTH/2, 350)
    end
end

function receiveData(d)
    msgs[#msgs+1] = d
    sound(DATA, "ZgJAOgAzQFRrUD9AMgRrPcgXCT4Ps4A+OgBAaEBAQEJCQC9d")
end

function keyboard(key)
    if (key == BACKSPACE) then
        msg = string.sub(msg, 1, -2)
    elseif (key == RETURN) then
        sendMsg(msg, Username)
        msg = ""
    else
        msg = msg .. key
    end
end

function sendMsg(toSend, tag)
    msgs[#msgs+1] = tag .. ": " .. toSend
    multihandler:sendData(tag .. ": " .. toSend)
    sound(DATA, "ZgJAMABMQFRrUD9AMgRrPcgXCT4Ps4A+OgBAaEBAQEJCQC9d")
end

local socket = require("socket")

Multiuser = class()

function Multiuser:init(dcb, ccb)
    self.my_ip, self.my_port = self:getLocalIP(), 5400
    self.peer_ip, self.peer_port = nil, self.my_port

    self.client = socket.udp()
    self.client:settimeout(0)

    self.connected = false
    self.is_host = false
    self.searching = false

    self.dataCallback = dcb or function() end
    self.connectedCallback = ccb or function() end
end

-- Returns this iPad's local ip
function Multiuser:getLocalIP()
    local randomIP = "192.167.188.122"
    local randomPort = "3102" 
    local randomSocket = socket.udp() 
    randomSocket:setpeername(randomIP,randomPort) 

    local localIP, somePort = randomSocket:getsockname()

    randomSocket:close()
    randomSocket = nil

    return localIP
end

-- Set the connected status and call the connection callback if needed
function Multiuser:setConnectedVal(bool)
    self.connected = bool

    if self.connected then
        self.connectedCallback()
    end
end

function Multiuser:setHostVal(bool)
    self.is_host = bool
end

-- Prepare to be the host
function Multiuser:hostRoom()
    print("Connect to " .. self.my_ip .. ":" .. self.my_port)

    self.client:setsockname(self.my_ip, self.my_port)

    self:setConnectedVal(false)
    self.is_host = true
    self.searching = false
end

-- Find a host
function Multiuser:findRoom()
    print("Searching for rooms...")

    self.searching = true

    local ip_start, ip_end = self.my_ip:match("(%d+.%d+.%d+.)(%d+)")
    for i = 1, 255 do
        if i ~= tonumber(ip_end) then
            tween.delay(0.01 * i, function()
                self.client:setsockname(ip_start .. i, self.my_port)
                self.client:sendto("connection_confirmation", ip_start .. i, self.my_port)
            end)
        end
    end
end

-- Prepare to join a host
function Multiuser:joinRoom(ip, port)
    self.peer_ip, self.peer_port = ip, port

    self.client:setsockname(ip, port)

    self.is_host = false
    self.searching = false

    self:sendData("connection_confirmation")
end

-- Send data to the other client
function Multiuser:sendData(msg_to_send)
    if self.peer_ip then
        self.client:sendto(msg_to_send, self.peer_ip, self.peer_port)
    end
end

-- Check for data received from the other client
function Multiuser:checkForReceivedData()
    local data, msg_or_ip, port_or_nil = self.client:receivefrom()
    if data then
            -- Store the ip of this new client so you can send data back
            self.peer_ip, self.peer_port = msg_or_ip, port_or_nil

            if not self.connected and data == "connection_confirmation" then
                self:sendData("connection_confirmation")
                self:setConnectedVal(true)
            end

            -- Call callback with received data
            if data ~= "connection_confirmation" then
                self.dataCallback(data)
            end
    end
end

function Multiuser:update()
    self:checkForReceivedData()
end