chk_mod.lua

   1 -- libquvi-scripts
   2 -- Copyright (C) 2012  Toni Gundogdu <legatvs@gmail.com>
   3 --
   4 -- This file is part of libquvi-scripts <http://quvi.sourceforge.net/>.
   5 --
   6 -- This program is free software: you can redistribute it and/or
   7 -- modify it under the terms of the GNU Affero General Public
   8 -- License as published by the Free Software Foundation, either
   9 -- version 3 of the License, or (at your option) any later version.
  10 --
  11 -- This program is distributed in the hope that it will be useful,
  12 -- but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 -- GNU Affero General Public License for more details.
  15 --
  16 -- You should have received a copy of the GNU Affero General
  17 -- Public License along with this program.  If not, see
  18 -- <http://www.gnu.org/licenses/>.
  19 --
  20
  21 --
  22 -- Checks the availability of a Lua module.
  23 --
  24 -- NOTES:
  25 --  * Exits with either 0 (success) or 1 (failure)
  26 --  * Informative messages are printed to stdout
  27 --
  28
  29 local EXIT_SUCCESS = 0
  30 local EXIT_FAILURE = 1
  31
  32 local function _chk_input()
  33   if #arg <2 then
  34     print(string.format('Usage: %s <modname> <reqver>', arg[0]))
  35     print('  Exit status: 0=success, 1=failure')
  36     print(string.format('Example: %s lxp 1.2.0', arg[0]))
  37     os.exit(EXIT_FAILURE)
  38   end
  39 end
  40
  41 local function _chk_form(a,b,c,s)
  42   if not a or not b or not c then
  43     print(string.format('error: %s must be in the x.y.z form', s))
  44     os.exit(EXIT_FAILURE)
  45   end
  46 end
  47
  48 local function _to_n(a,b,c)
  49   return tonumber(string.format('%d%d%d',
  50                     tonumber(a), tonumber(b), tonumber(c)))
  51 end
  52
  53 local function _chk_mod(m,r)
  54   local p = '(%d+).(%d+).(%d+)'
  55
  56   local ra,rb,rc = r:match(p)
  57   _chk_form(ra,rb,rc,'reqver')
  58
  59   local M = require(m)
  60
  61   local fa,fb,fc = M._VERSION:match(p)
  62   _chk_form(fa,fb,fc,'modver')
  63
  64   print('require', ra,rb,rc)
  65   print('found', fa,fb,fc)
  66
  67   return (_to_n(fa,fb,fc) >= _to_n(ra,rb,rc))
  68             and EXIT_SUCCESS or EXIT_FAILURE
  69 end
  70
  71 _chk_input()
  72 os.exit(_chk_mod(arg[1], arg[2]))