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 local function _assert( condition, fmt, ... )
  20         if not condition then
  21                 return assert( nil, string.format( fmt, ... ) )
  22         else
  23                 return condition
  24         end
  25 end
  26
  27
  28 function _parse_reference( r, c, s, o )
  29         local ref  = { }
  30         local vars = {
  31                 config  = c,
  32                 section = s,
  33                 option  = o
  34         }
  35
  36         for i, v in ipairs(luci.util.split(r,".")) do
  37                 table.insert( ref, (v:gsub( "%$(.+)", function(n) return vars[n] end )) )
  38         end
  39
  40         if #ref == 1 and c and s then
  41                 ref = { c, s, ref[1] }
  42         elseif #ref == 2 and c then
  43                 ref = { c, unpack(ref) }
  44         elseif #ref ~= 3 then
  45                 ref = nil
  46         end
  47
  48         return ref
  49 end
  50
  51 function check( self, object, nodeps )
  52
  53         if not self.beenthere[object:cid()] then
  54                 self.beenthere[object:cid()] = true
  55         else
  56                 return false, "Recursive dependency for '" .. object:sid() .. "' found"
  57         end
  58
  59         local item = object.type == luci.uvl.TYPE_SECTION
  60                 and object:section() or object:option()
  61
  62         if item.depends then
  63                 local ok = false
  64                 local valid, err = false,
  65                         string.format( 'In dependency check for %s "%s":',
  66                                 ( object.type == luci.uvl.TYPE_SECTION and "section" or "option" ),
  67                                 object:cid() )
  68
  69                 for _, dep in ipairs(item.depends) do
  70                         local subcondition = true
  71                         for k, v in pairs(dep) do
  72                                 -- XXX: better error
  73                                 local ref = _parse_reference( k, unpack(object.cref) )
  74
  75                                 if not ref then
  76                                         return false, "Ambiguous dependency reference '" .. k ..
  77                                                 "' for object '" .. object:sid() .. "' given"
  78                                 end
  79
  80                                 local option = luci.uvl.option(
  81                                         self, object.config,
  82                                         object.config[ref[2]]
  83                                                 and object.config[ref[2]]['.type']
  84                                                 or  object.sref[2],
  85                                         ref[1], ref[2], ref[3]
  86                                 )
  87
  88                                 valid, err2 = self:_validate_option( option, true )
  89                                 if valid then
  90                                         if not (
  91                                                 ( type(v) == "boolean" and object.config[ref[2]][ref[3]] ) or
  92                                                 ( ref[3] and object.config[ref[2]][ref[3]] ) == v
  93                                         ) then
  94                                                 subcondition = false
  95                                                 err = err .. "\n" ..
  96                                                         self.log.dump_dependency( dep, ref, v )
  97                                                 break
  98                                         end
  99                                 else
 100                                         subcondition = false
 101                                         err = err .. "\n" ..
 102                                                 self.log.dump_dependency( dep, ref, nil, err2 )
 103                                         break
 104                                 end
 105                         end
 106
 107                         if subcondition then
 108                                 return true
 109                         end
 110                 end
 111
 112                 return false, err
 113         end
 114
 115         return true
 116 end