summaryrefslogtreecommitdiff
path: root/src/tcpserver.lua
blob: 85992c3b8386f1d5a867f98eb4985557ef08f09a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
--
--  rhnop
--
--  Copyright (C) 2011-2015 Christian Pointner <equinox@helsinki.at>
--
--  This file is part of rhnop.
--
--  rhnop is free software: you can redistribute it and/or modify
--  it under the terms of the GNU General Public License as published by
--  the Free Software Foundation, either version 3 of the License, or
--  any later version.
--
--  rhnop is distributed in the hope that it will be useful,
--  but WITHOUT ANY WARRANTY; without even the implied warranty of
--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
--  GNU General Public License for more details.
--
--  You should have received a copy of the GNU General Public License
--  along with rhnop. If not, see <http://www.gnu.org/licenses/>.
--

require "socket"

package.path = package.path .. ";" .. rhnoplibdir .. "/?.lua"
conf = require "conf"

function init_server()
   local server = assert(socket.tcp())
   
   assert(server:setoption('reuseaddr', true))
   assert(server:bind(conf.tcp_host, conf.tcp_port))
   assert(server:listen(5))

   return server
end

local clients = {}

function add_client(hdl)
   -- print("new client(" .. hdl:getfd() .. ") from " .. hdl:getpeername())
   local client = {}
   client.buffer = ""
   client.hdl = hdl
   client.getfd = function() return hdl:getfd() end
   client.dirty = function() return hdl:dirty() end
   table.insert(clients, client)
end

function remove_client(c)
   local idx = 0
   for idx, client in ipairs(clients) do
      if client == c then
         break
      end
   end

   -- print("removing client(" .. c.hdl:getfd() .. ")")
   c.hdl:close()
   table.remove(clients, idx)
end

function cleanup_clients()
   for _, client in ipairs(clients) do
      client:close()
   end
end

function clients_get_writeables()
   local fds = {}
   
   for _, client in ipairs(clients) do
      if client.buffer ~= "" then
         table.insert(fds, client)
      end
   end

   return fds
end

function clients_senddata(timestamp)
   for _, client in ipairs(clients) do
      client.buffer  = client.buffer .. timestamp .. "\n"
   end
end

function main_loop()
   local pipefd = pipe.getreadfd()

   server = init_server()
   while true do
      local readables, writeables, err = socket.select({ pipefd , server , unpack(clients) } , clients_get_writeables())
      if err then
         print("select returned with error: " .. err)
         return -1
      else
         for _, input in ipairs(readables) do
            if input == pipefd then
               local timestamp = pipe.consume()
               if timestamp == nil then
                  return 2
               end
               -- print("pipe was signaled with timestamp: " .. timestamp)
               clients_senddata(timestamp)
            elseif input == server then
               local client = assert(server:accept())
               add_client(client)
            else
               if input.hdl then
                  -- receive is insanely stupid, therefore we must always read one byte only
                  local _, err = input.hdl:receive(1)
                  if err then
                     remove_client(input)
                  end
               end
            end
         end

         for _, output in ipairs(writeables) do
            local ret = output.hdl:send(output.buffer)
            if(ret == nil) then
               remove_client(output)
            else
               output.buffer = string.sub(output.buffer, ret+1)
            end
         end
      end
   end

   server:close()
   cleanup_clients()   

   return 0
end