libs/httpd/luasrc/httpd.lua

   1 --[[
   2
   3 HTTP server implementation for LuCI - core
   4 (c) 2008 Freifunk Leipzig / Jo-Philipp Wich <xm@leipzig.freifunk.net>
   5
   6 Licensed under the Apache License, Version 2.0 (the "License");
   7 you may not use this file except in compliance with the License.
   8 You may obtain a copy of the License at
   9
  10         http://www.apache.org/licenses/LICENSE-2.0
  11
  12 $Id$
  13
  14 ]]--
  15
  16 module("luci.httpd", package.seeall)
  17 require("socket")
  18 require("luci.util")
  19
  20 function Socket(ip, port)
  21         local sock, err = socket.bind( ip, port )
  22
  23         if sock then
  24                 sock:settimeout( 0, "t" )
  25         end
  26
  27         return sock, err
  28 end
  29
  30 Thread = luci.util.class()
  31
  32 function Thread.__init__(self, socket, func)
  33         self.socket  = socket
  34         self.routine = coroutine.create(func)
  35         self.stamp   = os.time()
  36         self.waiting = false
  37 end
  38
  39 function Thread.touched(self)
  40         return self.stamp
  41 end
  42
  43 function Thread.iswaiting(self)
  44         return self.waiting
  45 end
  46
  47 function Thread.receive(self, ...)
  48         local chunk, err, part
  49         self.waiting = true
  50
  51         repeat
  52                 coroutine.yield()
  53                 chunk, err, part = self.socket:receive(...)
  54         until err ~= "timeout"
  55
  56         self.waiting = false
  57         return chunk, err, part
  58 end
  59
  60 function Thread.resume(self, ...)
  61         return coroutine.resume(self.routine, self, ...)
  62 end
  63
  64 function Thread.isdead(self)
  65         return coroutine.status(self.routine) == "dead"
  66 end
  67
  68 function Thread.touch(self)
  69         self.stamp = os.time()
  70 end
  71
  72 Daemon = luci.util.class()
  73
  74 function Daemon.__init__(self, threadlimit, waittime, timeout)
  75         self.reading = {}
  76         self.threads = {}
  77         self.handler = {}
  78         self.waiting = {}
  79         self.threadc = 0
  80
  81         setmetatable(self.waiting, {__mode = "v"})
  82
  83         self.debug   = false
  84         self.threadlimit = threadlimit
  85         self.waittime = waittime or 0.1
  86         self.timeout  = timeout or 90
  87 end
  88
  89 function Daemon.remove_dead(self, thread)
  90         if self.debug then
  91                 self:dprint("Completed " .. tostring(thread))
  92         end
  93         thread.socket:close()
  94         self.threadc = self.threadc - 1
  95         self.threads[thread.socket] = nil
  96 end
  97
  98 function Daemon.kill_timedout(self)
  99         local now = os.time()
 100
 101         for sock, thread in pairs(self.threads) do
 102                 if os.difftime(now, thread:touched()) > self.timeout then
 103                         self.threads[sock] = nil
 104                         self.threadc = self.threadc - 1
 105                         sock:close()
 106                 end
 107         end
 108 end
 109
 110 function Daemon.dprint(self, msg)
 111         if self.debug then
 112                 io.stderr:write("[daemon] " .. msg .. "\n")
 113         end
 114 end
 115
 116 function Daemon.register(self, sock, clhandler, errhandler)
 117         table.insert( self.reading, sock )
 118         self.handler[sock] = { clhandler = clhandler, errhandler = errhandler }
 119 end
 120
 121 function Daemon.run(self)
 122         while true do
 123                 self:step()
 124         end
 125 end
 126
 127 function Daemon.step(self)
 128         local input, output, err = socket.select( self.reading, nil, 0 )
 129         local working = false
 130
 131         -- accept new connections
 132         for i, connection in ipairs(input) do
 133
 134                 local sock = connection:accept()
 135
 136                 if sock then
 137                         -- check capacity
 138                         if not self.threadlimit or self.threadc < self.threadlimit then
 139
 140                                 if self.debug then
 141                                         self:dprint("Accepted incoming connection from " .. sock:getpeername())
 142                                 end
 143
 144                                 local t = Thread(sock, self.handler[connection].clhandler)
 145                                 self.threads[sock] = t
 146                                 self.threadc = self.threadc + 1
 147
 148                                 if self.debug then
 149                                         self:dprint("Created " .. tostring(t))
 150                                 end
 151
 152                         -- reject client
 153                         else
 154                                 self:kill_timedout()
 155
 156                                 if self.debug then
 157                                         self:dprint("Rejected incoming connection from " .. sock:getpeername())
 158                                 end
 159
 160                                 if self.handler[connection].errhandler then
 161                                         self.handler[connection].errhandler( sock )
 162                                 end
 163
 164                                 sock:close()
 165                         end
 166                 end
 167         end
 168
 169         -- create client handler
 170         for sock, thread in pairs( self.threads ) do
 171                 -- resume working threads
 172                 if not thread:iswaiting() then
 173                         if self.debug then
 174                                 self:dprint("Resuming " .. tostring(thread))
 175                         end
 176
 177                         local stat, err = thread:resume()
 178                         if stat and not thread:isdead() then
 179                                 thread:touch()
 180                                 if not thread:iswaiting() then
 181                                         working = true
 182                                 else
 183                                         table.insert(self.waiting, sock)
 184                                 end
 185                         else
 186                                 self:remove_dead(thread)
 187                         end
 188
 189                         if self.debug then
 190                                 self:dprint(tostring(thread) .. " returned")
 191                                 if not stat then
 192                                         self:dprint("Error in " .. tostring(thread) .. " " .. err)
 193                                 end
 194                         end
 195                 end
 196         end
 197
 198         -- check for data on waiting threads
 199         input, output, err = socket.select( self.waiting, nil, 0 )
 200
 201         for i, sock in ipairs(input) do
 202                 local thread = self.threads[sock]
 203                 thread:resume()
 204                 if thread:isdead() then
 205                         self:remove_dead(thread)
 206                 else
 207                         thread:touch()
 208
 209                         if not thread:iswaiting() then
 210                                 for i, s in ipairs(self.waiting) do
 211                                         if s == sock then
 212                                                 table.remove(self.waiting, i)
 213                                                 break
 214                                         end
 215                                 end
 216                                 if not working then
 217                                         working = true
 218                                 end
 219                         end
 220                 end
 221         end
 222
 223         if err == "timeout" and not working then
 224                 self:kill_timedout()
 225                 socket.sleep(self.waittime)
 226         end
 227 end