iteration

name_sever/lns.lua

@@ -0,0 +1,65 @@
+
+modem_location = "back"
+
+
+rednet.host("lns", "default")
+rednet.open(modem_location)
+
+local data = {}
+
+function save_data()
+    db = fs.open("lns.db", "w")
+    db.write(textutils.serialize(data))
+    db.close()
+end
+
+function load_data()
+    if fs.exists("lns.db") then
+        db = fs.open("lns.db", "r")
+        db_contents = db.readAll()
+        db.close()
+
+        data = textutils.unserialize(db_contents)
+    end
+end
+
+function split (inputstr, sep)
+    if sep == nil then
+       sep = "%s"
+    end
+    local t={}
+    for str in string.gmatch(inputstr, "([^"..sep.."]+)") do
+       table.insert(t, str)
+    end
+    return t
+ end
+
+load_data()
+
+while true do
+    client_id, msg = rednet.receive()
+
+    -- split string msg into action and hostname with ':' as a delimiter using string.unpack
+    local action, hostname = split(msg, ":")
+
+    if action == "lookup" then
+
+        -- check if hostname in data
+        if data[hostname] == nil then
+            rednet.send(client_id, "not found")
+        else
+            rednet.send(client_id, data[hostname])
+        end
+    end
+    
+    if action == "reload" then
+        load_data()
+        rednet.send(client_id, "ok")
+    end
+
+    if action == "register" then
+        data[hostname] = client_id
+        save_data()
+        rednet.send(client_id, "ok")
+    end
+end