source/texk/web2c/luatexdir/luasocket/samples/tinyirc.lua

   1 -----------------------------------------------------------------------------
   2 -- Select sample: simple text line server
   3 -- LuaSocket sample files.
   4 -- Author: Diego Nehab
   5 -----------------------------------------------------------------------------
   6 local socket = require("socket")
   7 host = host or "*"
   8 port1 = port1 or 8080
   9 port2 = port2 or 8181
  10 if arg then
  11     host = arg[1] or host
  12     port1 = arg[2] or port1
  13     port2 = arg[3] or port2
  14 end
  15
  16 server1 = assert(socket.bind(host, port1))
  17 server2 = assert(socket.bind(host, port2))
  18 server1:settimeout(1) -- make sure we don't block in accept
  19 server2:settimeout(1)
  20
  21 io.write("Servers bound\n")
  22
  23 -- simple set implementation
  24 -- the select function doesn't care about what is passed to it as long as
  25 -- it behaves like a table
  26 -- creates a new set data structure
  27 function newset()
  28     local reverse = {}
  29     local set = {}
  30     return setmetatable(set, {__index = {
  31         insert = function(set, value)
  32             if not reverse[value] then
  33                 table.insert(set, value)
  34                 reverse[value] = #set
  35             end
  36         end,
  37         remove = function(set, value)
  38             local index = reverse[value]
  39             if index then
  40                 reverse[value] = nil
  41                 local top = table.remove(set)
  42                 if top ~= value then
  43                     reverse[top] = index
  44                     set[index] = top
  45                 end
  46             end
  47         end
  48     }})
  49 end
  50
  51 set = newset()
  52
  53 io.write("Inserting servers in set\n")
  54 set:insert(server1)
  55 set:insert(server2)
  56
  57 while 1 do
  58     local readable, _, error = socket.select(set, nil)
  59     for _, input in ipairs(readable) do
  60         -- is it a server socket?
  61         if input == server1 or input == server2 then
  62             io.write("Waiting for clients\n")
  63             local new = input:accept()
  64             if new then
  65                 new:settimeout(1)
  66                 io.write("Inserting client in set\n")
  67                 set:insert(new)
  68             end
  69         -- it is a client socket
  70         else
  71             local line, error = input:receive()
  72             if error then
  73                 input:close()
  74                 io.write("Removing client from set\n")
  75                 set:remove(input)
  76             else
  77                 io.write("Broadcasting line '", line, "'\n")
  78                 writable, error = socket.skip(1, socket.select(nil, set, 1))
  79                 if not error then
  80                         for __, output in ipairs(writable) do
  81                         if output ~= input then
  82                             output:send(line .. "\n")
  83                         end
  84                         end
  85                 else io.write("No client ready to receive!!!\n") end
  86                         end
  87         end
  88     end
  89 end