libs/httpd/luasrc/httpd/server.lua

   1 --[[
   2
   3 HTTP server implementation for LuCI - helper class
   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.server", package.seeall)
  17
  18
  19 MAX_CLIENTS  = 15
  20 READ_BUFSIZE = 1024
  21
  22
  23 function error400( client, msg )
  24         client:send( "HTTP/1.0 400 Bad request\r\n" )
  25         client:send( "Content-Type: text/plain\r\n\r\n" )
  26
  27         if msg then
  28                 client:send( msg .. "\r\n" )
  29         end
  30
  31         client:close()
  32 end
  33
  34 function error503( client )
  35         client:send( "HTTP/1.0 503 Server unavailable\r\n" )
  36         client:send( "Content-Type: text/plain\r\n\r\n" )
  37         client:send( "There are too many clients connected, try again later\r\n" )
  38         client:close()
  39 end
  40
  41
  42 function client_handler(client)
  43
  44         client:settimeout( 0 )
  45
  46         -- Create LTN12 block source
  47         local block_source = function()
  48
  49                 coroutine.yield()
  50
  51                 local chunk, err, part = client:receive( READ_BUFSIZE )
  52
  53                 if chunk == nil and err == "timeout" then
  54                         return part
  55                 elseif chunk ~= nil then
  56                         return chunk
  57                 else
  58                         return nil, err
  59                 end
  60
  61         end
  62
  63         -- Create LTN12 line source
  64         local line_source = ltn12.source.simplify( function()
  65
  66                 coroutine.yield()
  67
  68                 local chunk, err, part = client:receive("*l")
  69
  70                 -- Line too long
  71                 if chunk == nil and err ~= "timeout" then
  72
  73                         return nil, part
  74                                 and "Line exceeds maximum allowed length["..part.."]"
  75                                 or  "Unexpected EOF"
  76
  77                 -- Line ok
  78                 else
  79
  80                         -- Strip trailing CR
  81                         chunk = chunk:gsub("\r$","")
  82
  83                         -- We got end of headers, switch to dummy source
  84                         if #chunk == 0 then
  85                                 return "", function()
  86                                         return nil
  87                                 end
  88                         else
  89                                 return chunk, nil
  90                         end
  91                 end
  92         end )
  93
  94         coroutine.yield(client)
  95
  96
  97         -- parse message
  98         local message, err = luci.http.protocol.parse_message_header( line_source )
  99
 100         if message then
 101
 102                 -- If we have a HTTP/1.1 client and an Expect: 100-continue header then
 103                 -- respond with HTTP 100 Continue message
 104                 if message.http_version == 1.1 and message.headers['Expect'] and
 105                         message.headers['Expect'] == '100-continue'
 106                 then
 107                         client:send("HTTP/1.1 100 Continue\r\n\r\n")
 108                 end
 109
 110
 111                 local s, e = luci.http.protocol.parse_message_body( block_source, message )
 112
 113                 -- XXX: debug
 114                 luci.util.dumptable( message )
 115
 116                 if not s and e then
 117                         error400( client, e )
 118                 end
 119         else
 120                 error400( client, err )
 121         end
 122
 123         -- send response
 124         error400( client, "Dummy response" )
 125 end