libs/uvl/luasrc/uvl/dependencies.lua

   1 --[[
   2
   3 UCI Validation Layer - Dependency helper
   4 (c) 2008 Jo-Philipp Wich <xm@leipzig.freifunk.net>
   5 (c) 2008 Steven Barth <steven@midlink.org>
   6
   7 Licensed under the Apache License, Version 2.0 (the "License");
   8 you may not use this file except in compliance with the License.
   9 You may obtain a copy of the License at
  10
  11         http://www.apache.org/licenses/LICENSE-2.0
  12
  13 $Id$
  14
  15 ]]--
  16
  17 module( "luci.uvl.dependencies", package.seeall )
  18
  19 function _parse_reference( r, c, s, o )
  20         local ref  = { }
  21         local vars = {
  22                 config  = c,
  23                 section = s,
  24                 option  = o
  25         }
  26
  27         for i, v in ipairs(luci.util.split(r,".")) do
  28                 table.insert( ref, (v:gsub( "%$(.+)", function(n) return vars[n] end )) )
  29         end
  30
  31         if #ref == 1 and c and s then
  32                 ref = { c, s, ref[1] }
  33         elseif #ref == 2 and c then
  34                 ref = { c, unpack(ref) }
  35         elseif #ref ~= 3 then
  36                 ref = nil
  37         end
  38
  39         return ref
  40 end
  41
  42 function check( self, object, nodeps )
  43
  44         if not self.beenthere[object:cid()] then
  45                 self.beenthere[object:cid()] = true
  46         else
  47                 return false, "Recursive dependency for '" .. object:sid() .. "' found"
  48         end
  49
  50         local item = object.type == luci.uvl.TYPE_SECTION
  51                 and object:section() or object:option()
  52
  53         if item.depends then
  54                 local ok = false
  55                 local valid, err = false,
  56                         string.format( 'In dependency check for %s "%s":',
  57                                 ( object.type == luci.uvl.TYPE_SECTION and "section" or "option" ),
  58                                 object:cid() )
  59
  60                 for _, dep in ipairs(item.depends) do
  61                         local subcondition = true
  62                         for k, v in pairs(dep) do
  63                                 -- XXX: better error
  64                                 local ref = _parse_reference( k, unpack(object.cref) )
  65
  66                                 if not ref then
  67                                         return false, "Ambiguous dependency reference '" .. k ..
  68                                                 "' for object '" .. object:sid() .. "' given"
  69                                 end
  70
  71                                 local option = luci.uvl.option(
  72                                         self, object.config,
  73                                         object.config[ref[2]]
  74                                                 and object.config[ref[2]]['.type']
  75                                                 or  object.sref[2],
  76                                         ref[1], ref[2], ref[3]
  77                                 )
  78
  79                                 valid, err2 = self:_validate_option( option, true )
  80                                 if valid then
  81                                         if not (
  82                                                 ( type(v) == "boolean" and object.config[ref[2]][ref[3]] ) or
  83                                                 ( ref[3] and object.config[ref[2]][ref[3]] ) == v
  84                                         ) then
  85                                                 subcondition = false
  86                                                 err = err .. "\n" ..
  87                                                         self.log.dump_dependency( dep, ref, v )
  88                                                 break
  89                                         end
  90                                 else
  91                                         subcondition = false
  92                                         err = err .. "\n" ..
  93                                                 self.log.dump_dependency( dep, ref, nil, err2 )
  94                                         break
  95                                 end
  96                         end
  97
  98                         if subcondition then
  99                                 return true
 100                         end
 101                 end
 102
 103                 return false, err
 104         end
 105
 106         return true
 107 end