Avoid lacking fds
[project/luci.git] / libs / sgi-cgi / luasrc / sgi / cgi.lua
1 --[[
2 LuCI - SGI-Module for CGI
3
4 Description:
5 Server Gateway Interface for CGI
6
7 FileId:
8 $Id$
9
10 License:
11 Copyright 2008 Steven Barth <steven@midlink.org>
12
13 Licensed under the Apache License, Version 2.0 (the "License");
14 you may not use this file except in compliance with the License.
15 You may obtain a copy of the License at 
16
17         http://www.apache.org/licenses/LICENSE-2.0 
18
19 Unless required by applicable law or agreed to in writing, software
20 distributed under the License is distributed on an "AS IS" BASIS,
21 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
22 See the License for the specific language governing permissions and
23 limitations under the License.
24
25 ]]--
26 module("luci.sgi.cgi", package.seeall)
27 local ltn12 = require("luci.ltn12")
28 require("nixio.util")
29 require("luci.http")
30 require("luci.sys")
31 require("luci.dispatcher")
32
33 -- Limited source to avoid endless blocking
34 local function limitsource(handle, limit)
35         limit = limit or 0
36         local BLOCKSIZE = ltn12.BLOCKSIZE
37
38         return function()
39                 if limit < 1 then
40                         handle:close()
41                         return nil
42                 else
43                         local read = (limit > BLOCKSIZE) and BLOCKSIZE or limit
44                         limit = limit - read
45
46                         local chunk = handle:read(read)
47                         if not chunk then handle:close() end
48                         return chunk
49                 end
50         end
51 end
52
53 function run()
54         local r = luci.http.Request(
55                 luci.sys.getenv(),
56                 limitsource(io.stdin, tonumber(luci.sys.getenv("CONTENT_LENGTH"))),
57                 ltn12.sink.file(io.stderr)
58         )
59         
60         local x = coroutine.create(luci.dispatcher.httpdispatch)
61         local hcache = ""
62         local active = true
63         
64         while coroutine.status(x) ~= "dead" do
65                 local res, id, data1, data2 = coroutine.resume(x, r)
66
67                 if not res then
68                         print("Status: 500 Internal Server Error")
69                         print("Content-Type: text/plain\n")
70                         print(id)
71                         break;
72                 end
73
74                 if active then
75                         if id == 1 then
76                                 io.write("Status: " .. tostring(data1) .. " " .. data2 .. "\r\n")
77                         elseif id == 2 then
78                                 hcache = hcache .. data1 .. ": " .. data2 .. "\r\n"
79                         elseif id == 3 then
80                                 io.write(hcache)
81                                 io.write("\r\n")
82                         elseif id == 4 then
83                                 io.write(tostring(data1 or ""))
84                         elseif id == 5 then
85                                 io.flush()
86                                 io.close()
87                                 active = false
88                         elseif id == 6 then
89                                 data1:copyz(nixio.stdout, data2)
90                                 data1:close()
91                         end
92                 end
93         end
94 end