wmii.lua

   1 --
   2 -- Copyrigh (c) 2007, Bart Trojanowski <bart@jukie.net>
   3 --
   4 -- Simple wmiir like interface.
   5 --
   6 -- The current intent is to wrap around the wmiir executable.
   7 -- This is just a proof of concept, and eventually this will
   8 -- be rewritten in C to use libixp.
   9 --
  10 local base = _G
  11 local io = require("io")
  12 local os = require("os")
  13 local posix = require("posix")
  14 local string = require("string")
  15 local print = print
  16 local pairs = pairs
  17
  18 module("wmii")
  19
  20 local wmiir = "wmiir"
  21
  22 -- ------------------------------------------------------------------------
  23 -- TODO I would like to be able to return an interator
  24 function ls (dir, fmt)
  25         local tmpfile = os.tmpname()
  26         local fmt = fmt or ""
  27
  28         os.execute (wmiir .. " ls " .. fmt .. " " .. dir .. " > " .. tmpfile)
  29
  30         local fh = io.open (tmpfile, "rb")
  31         os.remove (tmpfile)
  32
  33         local data = fh:read("*a")      -- read everything
  34
  35         io.close (fh)
  36
  37         return data
  38 end
  39
  40 -- ------------------------------------------------------------------------
  41 -- read all contents of a wmii virtual file
  42 function read (file)
  43         local tmpfile = os.tmpname()
  44
  45         os.execute (wmiir .. " read " .. file .. " > " .. tmpfile)
  46
  47         local fh = io.open (tmpfile, "rb")
  48         os.remove (tmpfile)
  49
  50         local data = fh:read("*a")      -- read all
  51         io.close (fh)
  52
  53         return data
  54 end
  55
  56 -- ------------------------------------------------------------------------
  57 -- return an iterator which walks all the lines in the file
  58 --
  59 -- example:
  60 --     for event in wmii.iread("/event")
  61 --         ...
  62 --     end
  63 function iread (file)
  64         local tmpfile = os.tmpname()
  65         os.remove (tmpfile)
  66
  67         io.write ("-- tmpname " .. tmpfile .. "\n")
  68
  69         local rc = posix.mkfifo (tmpfile)
  70         io.write ("-- mkfifo " .. rc .. "\n")
  71
  72         rc = posix.fork ()
  73         if rc < 0 then
  74                 io.write ("-- fork failed " .. rc .. "\n")
  75                 return function ()
  76                         return nil
  77                 end
  78         end
  79         if rc == 0 then -- child
  80                 os.execute (wmiir .. " read " .. file .. " > " .. tmpfile)
  81                 posix.exec ("/usr/bin/env", "cat", "/dev/null")
  82         end
  83
  84         -- parent
  85
  86         local fh = io.open (tmpfile, "rb")
  87         os.remove (tmpfile)
  88
  89         return function ()
  90                 local line = fh:read("*l")      -- read a line
  91                 if not line then
  92                         io.write ("-- closing " .. file .. "\n")
  93                         io.close (fh)
  94                 end
  95                 return line
  96         end
  97 end
  98
  99 -- ------------------------------------------------------------------------
 100 -- returns an events iterator
 101 function ievents ()
 102         local it = iread("/event")
 103
 104         return function ()
 105                 local line = it()
 106                 return string.match(line, "(%S+)%s(.+)")
 107         end
 108 end
 109
 110 -- ------------------------------------------------------------------------
 111 -- write a value to a wmii virtual file system
 112 function write (file, value)
 113         local tmpfile = os.tmpname()
 114
 115         local fh = io.open (tmpfile, "wb")
 116         fh:write(value)
 117         io.close (fh)
 118
 119         os.execute (wmiir .. " write " .. file .. " < " .. tmpfile)
 120         os.remove (tmpfile)
 121 end
 122
 123 -- ------------------------------------------------------------------------
 124 -- write a value to a wmii virtual file system
 125 function configure (config)
 126         local x, y
 127         for x, y in pairs(config) do
 128                 write ("/ctl", x .. " " .. y)
 129         end
 130 end
 131