X-Git-Url: https://git.archive.openwrt.org/?p=project%2Fluci.git;a=blobdiff_plain;f=libs%2Fuvl%2Fluasrc%2Fuvl.lua;fp=libs%2Fuvl%2Fluasrc%2Fuvl.lua;h=0000000000000000000000000000000000000000;hp=d2ea4bd2c249a93d042a731d09a0816792d5230e;hb=052f65950cc195adc1589566ca9725de0ad83c63;hpb=800a2630497e1ec2c61199b3bc645d778c714529

diff --git a/libs/uvl/luasrc/uvl.lua b/libs/uvl/luasrc/uvl.lua
deleted file mode 100644
index d2ea4bd2c..000000000
--- a/libs/uvl/luasrc/uvl.lua
+++ /dev/null
@@ -1,1213 +0,0 @@
---[[
-
-UCI Validation Layer - Main Library
-(c) 2008 Jo-Philipp Wich <xm@leipzig.freifunk.net>
-(c) 2008 Steven Barth <steven@midlink.org>
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-		http://www.apache.org/licenses/LICENSE-2.0
-
-$Id$
-
-]]--
-
-
---- UVL - UCI Validation Layer
--- @class	module
--- @cstyle	instance
-
-local fs = require "nixio.fs"
-local uci = require "luci.model.uci"
-local util = require "luci.util"
-local nutil = require "nixio.util"
-local table = require "table"
-local string = require "string"
-
-local require, pcall, ipairs, pairs = require, pcall, ipairs, pairs
-local type, error, tonumber, tostring = type, error, tonumber, tostring
-local unpack, loadfile, collectgarbage = unpack, loadfile, collectgarbage
-
-module "luci.uvl"
-
-local ERR = require "luci.uvl.errors".error
-local datatypes = require "luci.uvl.datatypes"
-local validation = require "luci.uvl.validation"
-local dependencies = require "luci.uvl.dependencies"
-
-local TYPE_SCHEME   = 0x00
-local TYPE_CONFIG   = 0x01
-local TYPE_SECTION  = 0x02
-local TYPE_OPTION   = 0x03
-local TYPE_ENUM     = 0x04
-
-local PAT_EXPR1		= "^%$?[%w_]+$"
-local PAT_EXPR2		= "^%$?[%w_]+%.%$?[%w_]+$"
-local PAT_EXPR3		= "^%$?[%w_]+%.%$?[%w_]+%.%$?[%w_]+$"
-
---- Boolean; default true;
--- treat sections found in config but not in scheme as error
-STRICT_UNKNOWN_SECTIONS    = true
-
---- Boolean; default true;
--- treat options found in config but not in scheme as error
-STRICT_UNKNOWN_OPTIONS     = true
-
---- Boolean; default true;
--- treat failed external validators as error
-STRICT_EXTERNAL_VALIDATORS = true
-
---- Boolean; default true;
--- treat list values stored as options like errors
-STRICT_LIST_TYPE           = true
-
-
-local default_schemedir = "/lib/uci/schema"
-local default_savedir = "/tmp/.uvl"
-
-
---- Object constructor
--- @class			function
--- @name			UVL
--- @param schemedir	Path to the scheme directory (optional)
--- @param configdir	Override config directory (optional)
--- @return			Instance object
-UVL = util.class()
-
-function UVL.__init__( self, schemedir, configdir )
-	self.schemedir	= schemedir or default_schemedir
-	self.configdir	= configdir
-	self.packages	= { }
-	self.beenthere  = { }
-	self.depseen    = { }
-	self.uci		= uci
-	self.err		= ERR
-	self.dep		= dependencies
-	self.datatypes  = datatypes
-end
-
-
---- Parse given scheme and return the scheme tree.
--- @param scheme	Name of the scheme to parse
--- @return			Table containing the parsed scheme or nil on error
--- @return			String containing the reason for errors (if any)
-function UVL.get_scheme( self, scheme )
-	if not self.packages[scheme] then
-		local ok, err = self:read_scheme( scheme )
-		if not ok then
-			return nil, err
-		end
-	end
-	return self.packages[scheme], nil
-end
-
---- Validate given configuration, section or option.
--- @param config	Name of the configuration to validate
--- @param section	Name of the section to validate (optional)
--- @param option	Name of the option to validate (optional)
--- @return			Boolean indicating whether the given config validates
--- @return			String containing the reason for errors (if any)
-function UVL.validate( self, config, section, option )
-	if config and section and option then
-		return self:validate_option( config, section, option )
-	elseif config and section then
-		return self:validate_section( config, section )
-	elseif config then
-		return self:validate_config( config )
-	end
-end
-
---- Validate given configuration.
--- @param cfg	Name of the configuration to validate
--- @return			Boolean indicating whether the given config validates
--- @return			String containing the reason for errors (if any)
-function UVL.validate_config( self, cfg, uci )
-
-	if not self.packages[cfg] then
-		local ok, err = self:read_scheme(cfg)
-		if not ok then
-			return false, err
-		end
-	end
-
-	local co = config( self, uci or cfg, uci and cfg )
-	local sc = { }
-
-	self.beenthere = { }
-	self.depseen   = { }
-
-	if not co:config() then
-		return false, co:errors()
-	end
-
-	local function _uci_foreach( type, func )
-		for k, v in pairs(co:config()) do
-			if v['.type'] == type then
-				sc[type] = sc[type] + 1
-				local ok, err = func( k, v )
-				if not ok then co:error(err) end
-			end
-		end
-	end
-
-	for k, v in pairs( self.packages[cfg].sections ) do
-		sc[k] = 0
-		_uci_foreach( k,
-			function(s)
-				return self:_validate_section( co:section(s) )
-			end
-		)
-	end
-
-	if STRICT_UNKNOWN_SECTIONS then
-		for k, v in pairs(co:config()) do
-			local so = co:section(k)
-			if not self.beenthere[so:cid()] then
-				co:error(ERR('SECT_UNKNOWN', so))
-			end
-		end
-	end
-
-	for _, k in ipairs(util.keys(sc)) do
-		local so = co:section(k)
-		if so:scheme('required') and sc[k] == 0 then
-			co:error(ERR('SECT_REQUIRED', so))
-		elseif so:scheme('unique') and sc[k] > 1 then
-			co:error(ERR('SECT_UNIQUE', so))
-		end
-	end
-
-	return co:ok(), co:errors()
-end
-
---- Validate given config section.
--- @param config	Name of the configuration to validate
--- @param section	Name of the section to validate
--- @return			Boolean indicating whether the given config validates
--- @return			String containing the reason for errors (if any)
-function UVL.validate_section( self, cfg, section, uci )
-
-	if not self.packages[cfg] then
-		local ok, err = self:read_scheme( cfg )
-		if not ok then
-			return false, err
-		end
-	end
-
-	local co = config( self, uci or cfg, uci and cfg )
-	local so = co:section( section )
-
-	self.beenthere = { }
-	self.depseen   = { }
-
-	if not co:config() then
-		return false, co:errors()
-	end
-
-	if so:config() then
-		return self:_validate_section( so )
-	else
-		return false, ERR('SECT_NOTFOUND', so)
-	end
-end
-
---- Validate given config option.
--- @param config	Name of the configuration to validate
--- @param section	Name of the section to validate
--- @param option	Name of the option to validate
--- @return			Boolean indicating whether the given config validates
--- @return			String containing the reason for errors (if any)
-function UVL.validate_option( self, cfg, section, option, uci )
-
-	if not self.packages[cfg] then
-		local ok, err = self:read_scheme( cfg )
-		if not ok then
-			return false, err
-		end
-	end
-
-	local co = config( self, uci or cfg, uci and cfg )
-	local so = co:section( section )
-	local oo = so:option( option )
-
-	if not co:config() then
-		return false, co:errors()
-	end
-
-	if so:config() and oo:config() then
-		return self:_validate_option( oo )
-	else
-		return false, ERR('OPT_NOTFOUND', oo)
-	end
-end
-
-
-function UVL._validate_section( self, section )
-
-	self.beenthere[section:cid()] = true
-
-	if section:config() then
-		if section:scheme('named') == true and
-		   section:config('.anonymous') == true
-		then
-			return false, ERR('SECT_NAMED', section)
-		end
-
-		for _, v in ipairs(section:variables()) do
-			local ok, err = self:_validate_option( v )
-			if not ok and (
-				v:scheme('required') or v:scheme('type') == "enum" or (
-					not err:is('DEP_NOTEQUAL') and
-					not err:is('DEP_NOVALUE')
-				)
-			) then
-				section:error(err)
-			end
-		end
-
-		local ok, err = dependencies.check( self, section )
-		if not ok then
-			section:error(err)
-		end
-	else
-		return false, ERR('SECT_NOTFOUND', section)
-	end
-
-	if STRICT_UNKNOWN_OPTIONS and not section:scheme('dynamic') then
-		for k, v in pairs(section:config()) do
-			local oo = section:option(k)
-			if k:byte(1) == 46 and not self.beenthere[oo:cid()] then
-				section:error(ERR('OPT_UNKNOWN', oo))
-			end
-		end
-	end
-
-	return section:ok(), section:errors()
-end
-
-function UVL._validate_option( self, option, nodeps )
-
-	self.beenthere[option:cid()] = true
-
-	if not option:scheme() and not option:parent():scheme('dynamic') then
-		if STRICT_UNKNOWN_OPTIONS then
-			return false, option:error(ERR('OPT_UNKNOWN', option))
-		else
-			return true
-		end
-
-	elseif option:scheme() then
-		if not nodeps then
-			local ok, err = dependencies.check( self, option )
-			if not ok then
-				if not err:is_all(
-					'OPT_REQUIRED',
-					'DEP_NOTEQUAL',
-					'DEP_NOVALUE'
-				) then
-					option:error(err)
-					return false, option:errors()
-				else
-					return true
-				end
-			end
-		end
-
-		if option:scheme('required') and not option:value() then
-			return false, option:error(ERR('OPT_REQUIRED', option))
-
-		elseif option:value() then
-			local val = option:value()
-
-			if option:scheme('type') == "reference" or
-			   option:scheme('type') == "enum"
-			then
-				local scheme_values = option:scheme('values') or { }
-				local config_values = ( type(val) == "table" and val or { val } )
-				for _, v in ipairs(config_values) do
-					if not scheme_values[v] then
-						return false, option:error( ERR(
-							'OPT_BADVALUE',
-							option, { v, util.serialize_data(
-								util.keys(scheme_values)
-							) }
-						) )
-					end
-				end
-			elseif option:scheme('type') == "list" then
-				if type(val) ~= "table" and STRICT_LIST_TYPE then
-					return false, option:error(ERR('OPT_NOTLIST', option))
-				end
-			end
-
-			if option:scheme('datatype') then
-				local dt = option:scheme('datatype')
-
-				if self.datatypes[dt] then
-					val = ( type(val) == "table" and val or { val } )
-					for i, v in ipairs(val) do
-						if not self.datatypes[dt]( v ) then
-							return false, option:error(
-								ERR('OPT_INVVALUE', option, { v, dt })
-							)
-						end
-					end
-				else
-					return false, option:error(ERR('OPT_DATATYPE', option, dt))
-				end
-			end
-
-			val = ( type(val) == "table" and val or { val } )
-			for _, v in ipairs(val) do
-				if option:scheme('minlength') then
-					if #v < option:scheme('minlength') then
-						return false, option:error(ERR('OPT_RANGE', option))
-					end
-				end
-
-				if option:scheme('maxlength') then
-					if #v > option:scheme('maxlength') then
-						return false, option:error(ERR('OPT_RANGE', option))
-					end
-				end
-
-				local w = tonumber(v)
-
-				if option:scheme('minimum') then
-					if not w or w < option:scheme('minimum') then
-						return false, option:error(ERR('OPT_RANGE', option))
-					end
-				end
-
-				if option:scheme('maximum') then
-					if not w or w > option:scheme('maximum') then
-						return false, option:error(ERR('OPT_RANGE', option))
-					end
-				end
-			end
-		end
-
-		local ok, err = validation.check( self, option )
-		if not ok and STRICT_EXTERNAL_VALIDATORS then
-			return false, option:error(err)
-		end
-	end
-
-	return option:ok(), option:errors()
-end
-
---- Find all parts of given scheme and construct validation tree.
--- This is normally done on demand, so you don't have to call this function
--- by yourself.
--- @param shm	Name of the scheme to parse
--- @param alias		Create an alias for the loaded scheme
-function UVL.read_scheme( self, shm, alias )
-
-	local so = scheme( self, shm )
-	local bc = "%s/bytecode/%s.lua" %{ self.schemedir, shm }
-
-	if not fs.access(bc) then
-		local files = nutil.consume((fs.glob(self.schemedir .. '/*/' .. shm)))
-
-		if #files > 0 then
-			local ok, err
-			for _, file in ipairs(files) do
-				if not fs.access(file) then
-					return false, so:error(ERR('SME_READ', so,file))
-				end
-
-				local uci = uci.cursor( fs.dirname(file), default_savedir )
-
-				local sname = fs.basename(file)
-				local sd, err = uci:load( sname )
-
-				if not sd then
-					return false, ERR('UCILOAD', so, err)
-				end
-
-				ok, err = pcall(function()
-					uci:foreach(sname, "package", function(s)
-						self:_parse_package(so, s[".name"], s)
-					end)
-					uci:foreach(sname, "section", function(s)
-						self:_parse_section(so, s[".name"], s)
-					end)
-					uci:foreach(sname, "variable", function(s)
-						self:_parse_var(so, s[".name"], s)
-					end)
-					uci:foreach(sname, "enum", function(s)
-						self:_parse_enum(so, s[".name"], s)
-					end)
-
-				end)
-			end
-
-			if ok and alias then self.packages[alias] = self.packages[shm] end
-			return ok and self, err
-		else
-			return false, so:error(ERR('SME_FIND', so, self.schemedir))
-		end
-	else
-		local sc = loadfile(bc)
-		if sc then
-			self.packages[shm] = sc()
-			return true
-		else
-			return false, so:error(ERR('SME_READ',so,bc))
-		end
-	end
-end
-
--- helper function to check for required fields
-local function _req( t, n, c, r )
-	for i, v in ipairs(r) do
-		if not c[v] then
-			local p, o = scheme:sid(), nil
-
-			if t == TYPE_SECTION then
-				o = section( scheme, nil, p, n )
-			elseif t == TYPE_OPTION then
-				o = option( scheme, nil, p, '(nil)', n )
-			elseif t == TYPE_ENUM then
-				o = enum( scheme, nil, p, '(nil)', '(nil)', n )
-			end
-
-			return false, ERR('SME_REQFLD',o,v)
-		end
-	end
-	return true
-end
-
--- helper function to validate references
-local function _ref( c, t )
-	local r, k, n = {}
-	if c == TYPE_SECTION then
-		k = "package"
-		n = 1
-	elseif c == TYPE_OPTION then
-		k = "section"
-		n = 2
-	elseif c == TYPE_ENUM then
-		k = "variable"
-		n = 3
-	end
-
-	for o in t[k]:gmatch("[^.]+") do
-		r[#r+1] = o
-	end
-	r[1] = ( #r[1] > 0 and r[1] or scheme:sid() )
-
-	if #r ~= n then
-		return false, ERR('SME_BADREF', scheme, k)
-	end
-
-	return r
-end
-
--- helper function to read bools
-local function _bool( v )
-	return ( v == "true" or v == "yes" or v == "on" or v == "1" )
-end
-
--- Step 0: get package meta information
-function UVL._parse_package(self, scheme, k, v)
-	local sid = scheme:sid()
-	local pkg = self.packages[sid] or {
-		["name"]      = sid;
-		["sections"]  = { };
-		["variables"] = { };
-	}
-
-	pkg.title = v.title
-	pkg.description = v.description
-
-	self.packages[sid] = pkg
-end
-
--- Step 1: get all sections
-function UVL._parse_section(self, scheme, k, v)
-	local ok, err = _req( TYPE_SECTION, k, v, { "name", "package" } )
-	if err then error(scheme:error(err)) end
-
-	local r, err = _ref( TYPE_SECTION, v )
-	if err then error(scheme:error(err)) end
-
-	local p = self.packages[r[1]] or {
-		["name"]      = r[1];
-		["sections"]  = { };
-		["variables"] = { };
-	}
-	p.sections[v.name]  = p.sections[v.name]  or { }
-	p.variables[v.name] = p.variables[v.name] or { }
-	self.packages[r[1]] = p
-
-	local s  = p.sections[v.name]
-	local so = scheme:section(v.name)
-
-	for k, v2 in pairs(v) do
-		if k ~= "name" and k ~= "package" and k:byte(1) == 46 then
-			if k == "depends" then
-				s.depends = self:_read_dependency( v2, s.depends )
-				if not s.depends then
-					return false, scheme:error(
-						ERR('SME_BADDEP', so, util.serialize_data(s.depends))
-					)
-				end
-			elseif k == "dynamic" or k == "unique" or
-			       k == "required" or k == "named"
-			then
-				s[k] = _bool(v2)
-			else
-				s[k] = v2
-			end
-		end
-	end
-
-	s.dynamic  = s.dynamic  or false
-	s.unique   = s.unique   or false
-	s.required = s.required or false
-	s.named    = s.named    or false
-end
-
--- Step 2: get all variables
-function UVL._parse_var(self, scheme, k, v)
-	local ok, err = _req( TYPE_OPTION, k, v, { "name", "section" } )
-	if err then error(scheme:error(err)) end
-
-	local r, err = _ref( TYPE_OPTION, v )
-	if err then error(scheme:error(err)) end
-
-	local p = self.packages[r[1]]
-	if not p then
-		error(scheme:error(
-			ERR('SME_VBADPACK', {scheme:sid(), '', v.name}, r[1])
-		))
-	end
-
-	local s = p.variables[r[2]]
-	if not s then
-		error(scheme:error(
-			ERR('SME_VBADSECT', {scheme:sid(), '', v.name}, r[2])
-		))
-	end
-
-	s[v.name] = s[v.name] or { }
-
-	local t  = s[v.name]
-	local so = scheme:section(r[2])
-	local to = so:option(v.name)
-
-	for k, v2 in pairs(v) do
-		if k ~= "name" and k ~= "section" and k:byte(1) == 46 then
-			if k == "depends" then
-				t.depends = self:_read_dependency( v2, t.depends )
-				if not t.depends then
-					error(scheme:error(so:error(
-						ERR('SME_BADDEP', to, util.serialize_data(v2))
-					)))
-				end
-			elseif k == "validator" then
-				t.validators = self:_read_validator( v2, t.validators )
-				if not t.validators then
-					error(scheme:error(so:error(
-						ERR('SME_BADVAL', to, util.serialize_data(v2))
-					)))
-				end
-			elseif k == "valueof" then
-				local values, err = self:_read_reference( v2 )
-				if err then
-					error(scheme:error(so:error(
-						ERR('REFERENCE', to, util.serialize_data(v2)):child(err)
-					)))
-				end
-				t.type   = "reference"
-				t.values = values
-				t.valueof = type(v2) == "table" and v2 or {v2}
-			elseif k == "required" then
-				t[k] = _bool(v2)
-			elseif k == "minlength" or k == "maxlength" or
-                   k == "minimum" or k == "maximum"
-            then
-				t[k] = tonumber(v2)
-			else
-				t[k] = t[k] or v2
-			end
-		end
-	end
-
-	t.type     = t.type     or "variable"
-	t.datatype = t.datatype or "string"
-	t.required = t.required or false
-end
-
--- Step 3: get all enums
-function UVL._parse_enum(self, scheme, k, v)
-	local ok, err = _req( TYPE_ENUM, k, v, { "value", "variable" } )
-	if err then error(scheme:error(err)) end
-
-	local r, err = _ref( TYPE_ENUM, v )
-	if err then error(scheme:error(err)) end
-
-	local p = self.packages[r[1]]
-	if not p then
-		error(scheme:error(
-			ERR('SME_EBADPACK', {scheme:sid(), '', '', v.value}, r[1])
-		))
-	end
-
-	local s = p.variables[r[2]]
-	if not s then
-		error(scheme:error(
-			ERR('SME_EBADSECT', {scheme:sid(), '', '', v.value}, r[2])
-		))
-	end
-
-	local t = s[r[3]]
-	if not t then
-		error(scheme:error(
-			ERR('SME_EBADOPT', {scheme:sid(), '', '', v.value}, r[3])
-		))
-	end
-
-
-	local so = scheme:section(r[2])
-	local oo = so:option(r[3])
-	local eo = oo:enum(v.value)
-
-	if t.type ~= "enum" and t.type ~= "reference" then
-		error(scheme:error(ERR('SME_EBADTYPE', eo)))
-	end
-
-	if not t.values then
-		t.values = { [v.value] = v.title or v.value }
-		t.valuelist = { {value = v.value, title = v.title} }
-	else
-		t.values[v.value] = v.title or v.value
-		t.valuelist[#t.valuelist + 1] = {value = v.value, title = v.title}
-	end
-
-	if not t.enum_depends then
-		t.enum_depends = { }
-	end
-
-	if v.default then
-		if t.default then
-			error(scheme:error(ERR('SME_EBADDEF', eo)))
-		end
-		t.default = v.value
-	end
-
-	if v.depends then
-		t.enum_depends[v.value] = self:_read_dependency(
-			v.depends, t.enum_depends[v.value]
-		)
-
-		if not t.enum_depends[v.value] then
-			error(scheme:error(so:error(oo:error(
-				ERR('SME_BADDEP', eo, util.serialize_data(v.depends))
-			))))
-		end
-	end
-end
-
--- Read a dependency specification
-function UVL._read_dependency( self, values, deps )
-	local expr = "%$?[%w_]+"
-	if values then
-		values = ( type(values) == "table" and values or { values } )
-		for _, value in ipairs(values) do
-			local condition = { }
-			for val in value:gmatch("[^,]+") do
-				local k, e, v = val:match("%s*([%w$_.]+)%s*(=?)%s*(.*)")
-
-				if k and (
-					k:match(PAT_EXPR1) or k:match(PAT_EXPR2) or k:match(PAT_EXPR3)
-				) then
-					condition[k] = (e == '=') and v or true
-				else
-					return nil
-				end
-			end
-
-			if not deps then
-				deps = { condition }
-			else
-				deps[#deps+1] = condition
-			end
-		end
-	end
-
-	return deps
-end
-
--- Read a validator specification
-function UVL._read_validator( self, values, validators )
-	if values then
-		values = ( type(values) == "table" and values or { values } )
-		for _, value in ipairs(values) do
-			local validator
-
-			if value:match("^exec:") then
-				validator = value:gsub("^exec:","")
-			elseif value:match("^lua:") then
-				validator = self:_resolve_function( (value:gsub("^lua:","") ) )
-			elseif value:match("^regexp:") then
-				local pattern = value:gsub("^regexp:","")
-				validator = function( type, dtype, pack, sect, optn, arg1, arg2, arg3, arg4, arg5 )
-					local values = { arg1, arg2, arg3, arg4, arg5 }
-					for _, v in ipairs(values) do
-						local ok, match =
-							pcall( string.match, v, pattern )
-
-						if not ok then
-							return false, match
-						elseif not match then
-							return false,
-								'Value "%s" does not match pattern "%s"' % {
-									v, pattern
-								}
-						end
-					end
-					return true
-				end
-			end
-
-			if validator then
-				if not validators then
-					validators = { validator }
-				else
-					validators[#validators+1] = validator
-				end
-			else
-				return nil
-			end
-		end
-
-		return validators
-	end
-end
-
--- Read a reference specification (XXX: We should validate external configs too...)
-function UVL._read_reference( self, values )
-	local val = { }
-	values = ( type(values) == "table" and values or { values } )
-
-	for _, value in ipairs(values) do
-		local ref = util.split(value, ".")
-
-		if #ref == 2 or #ref == 3 then
-			local co = config( self, ref[1] )
-			if not co:config() then return false, co:errors() end
-
-			for k, v in pairs(co:config()) do
-				if v['.type'] == ref[2] then
-					if #ref == 2 then
-						if v['.anonymous'] == true then
-							return false, ERR('SME_INVREF', '', value)
-						end
-						val[k] = k	-- XXX: title/description would be nice
-					elseif v[ref[3]] then
-						val[v[ref[3]]] = v[ref[3]]  -- XXX: dito
-					end
-				end
-			end
-		else
-			return false, ERR('SME_BADREF', '', value)
-		end
-	end
-
-	return val, nil
-end
-
--- Resolve given path
-function UVL._resolve_function( self, value )
-	local path = util.split(value, ".")
-
-	for i=1, #path-1 do
-		local stat, mod = pcall(
-			require, table.concat(path, ".", 1, i)
-		)
-
-		if stat and mod then
-			for j=i+1, #path-1 do
-				if not type(mod) == "table" then
-					break
-				end
-				mod = mod[path[j]]
-				if not mod then
-					break
-				end
-			end
-			mod = type(mod) == "table" and mod[path[#path]] or nil
-			if type(mod) == "function" then
-				return mod
-			end
-		end
-	end
-end
-
-
---- Object representation of an uvl item - base class.
-uvlitem = util.class()
-
-function uvlitem.cid(self)
-	if #self.cref == 1 then
-		return self.cref[1]
-	else
-		local r = { unpack(self.cref) }
-		local c = self.c
-		if c and c[r[2]] and c[r[2]]['.anonymous'] and c[r[2]]['.index'] then
-			r[2] = '@' .. c[r[2]]['.type'] ..
-				   '[' .. tostring(c[r[2]]['.index']) .. ']'
-		end
-		return table.concat( r, '.' )
-	end
-end
-
-function uvlitem.sid(self)
-	return table.concat( self.sref, '.' )
-end
-
-function uvlitem.scheme(self, opt)
-	local s = self.s and self.s.packages
-	s = s      and s[self.sref[1]]
-	if #self.sref == 4 or #self.sref == 3 then
-		s = s      and s.variables
-		s = s      and s[self.sref[2]]
-		s = s      and s[self.sref[3]]
-	elseif #self.sref == 2 then
-		s = s      and s.sections
-		s = s      and s[self.sref[2]]
-	end
-
-	if s and opt then
-		return s[opt]
-	elseif s then
-		return s
-	end
-end
-
-function uvlitem.config(self, opt)
-	local c = self.c
-
-	if #self.cref >= 2 and #self.cref <= 4 then
-		c = c and self.c[self.cref[2]] or nil
-		if #self.cref >= 3 then
-			c = c and c[self.cref[3]] or nil
-		end
-	end
-
-	if c and opt then
-		return c[opt]
-	elseif c then
-		return c
-	end
-end
-
-function uvlitem.title(self)
-	return self:scheme() and self:scheme('title') or
-		self.cref[3] or self.cref[2] or self.cref[1]
-end
-
-function uvlitem.type(self)
-	if self.t == TYPE_CONFIG then
-		return 'config'
-	elseif self.t == TYPE_SECTION then
-		return 'section'
-	elseif self.t == TYPE_OPTION then
-		return 'option'
-	elseif self.t == TYPE_ENUM then
-		return 'enum'
-	end
-end
-
-function uvlitem.error(self, arg1, arg2, arg3, arg4, arg5)
-	if not self.e then
-		local errconst = { 'CONFIG', 'SECTION', 'OPTION', 'OPTION' }
-		self.e = ERR( errconst[#self.cref], self )
-	end
-
-	return self.e:child( arg1, arg2, arg3, arg4, arg5 )
-end
-
-function uvlitem.errors(self)
-	return self.e
-end
-
-function uvlitem.ok(self)
-	return not self:errors()
-end
-
-function uvlitem.parent(self)
-	if self.p then
-		return self.p
-	elseif #self.cref == 3 or #self.cref == 4 then
-		return section( self.s, self.c, self.cref[1], self.cref[2] )
-	elseif #self.cref == 2 then
-		return config( self.s, self.c, self.cref[1] )
-	else
-		return nil
-	end
-end
-
-function uvlitem._loadconf(self, co, c, configdir)
-	co = co or self._configcache
-	if not co then
-		local err
-		co, err = uci.cursor(configdir):get_all(c)
-
-		if err then
-			self:error(ERR('UCILOAD', self, err))
-		end
-
-		self._configcache = co
-	end
-	return co
-end
-
-
---- Object representation of a scheme.
--- @class	scheme
--- @cstyle	instance
--- @name	luci.uvl.scheme
-
---- Scheme instance constructor.
--- @class			function
--- @name			scheme
--- @param scheme	Scheme instance
--- @param co		Configuration data
--- @param c			Configuration name
--- @return			Config instance
-scheme = util.class(uvlitem)
-
-function scheme.__init__(self, scheme, co, c)
-	if not c then
-		c, co = co, nil
-	end
-
-	self.cref = { c }
-	self.sref = { c }
-	self.c    = self:_loadconf(co, c, scheme.configdir)
-	self.s    = scheme
-	self.t    = TYPE_SCHEME
-end
-
---- Add an error to scheme.
--- @return	Scheme error context
-function scheme.error(self, arg1, arg2, arg3, arg4, arg5)
-	if not self.e then self.e = ERR( 'SCHEME', self ) end
-	return self.e:child( arg1, arg2, arg3, arg4, arg5 )
-end
-
---- Get an associated config object.
--- @return	Config instance
-function scheme.config(self)
-	local co = config( self.s, self.cref[1] )
-	      co.p = self
-
-	return co
-end
-
---- Get all section objects associated with this scheme.
--- @return	Table containing all associated luci.uvl.section instances
-function scheme.sections(self)
-	local v = { }
-	if self.s.packages[self.sref[1]].sections then
-		for o, _ in pairs( self.s.packages[self.sref[1]].sections ) do
-			v[#v+1] = option(
-				self.s, self.c, self.cref[1], self.cref[2], o
-			)
-		end
-	end
-	return v
-end
-
---- Get an associated section object.
--- @param s	Section to select
--- @return	Section instance
-function scheme.section(self, s)
-	local so = section( self.s, self.c, self.cref[1], s )
-	      so.p = self
-
-	return so
-end
-
-
---- Object representation of a config.
--- @class	config
--- @cstyle	instance
--- @name	luci.uvl.config
-
---- Config instance constructor.
--- @class			function
--- @name			config
--- @param scheme	Scheme instance
--- @param co		Configuration data
--- @param c			Configuration name
--- @return			Config instance
-config = util.class(uvlitem)
-
-function config.__init__(self, scheme, co, c)
-	if not c then
-		c, co = co, nil
-	end
-	self.cref = { c }
-	self.sref = { c }
-	self.c    = self:_loadconf(co, c, scheme.configdir)
-	self.s    = scheme
-	self.t    = TYPE_CONFIG
-end
-
---- Get all section objects associated with this config.
--- @return	Table containing all associated luci.uvl.section instances
-function config.sections(self)
-	local v = { }
-	if self.s.packages[self.sref[1]].sections then
-		for o, _ in pairs( self.s.packages[self.sref[1]].sections ) do
-			v[#v+1] = option(
-				self.s, self.c, self.cref[1], self.cref[2], o
-			)
-		end
-	end
-	return v
-end
-
---- Get an associated section object.
--- @param s	Section to select
--- @return	Section instance
-function config.section(self, s)
-	local so = section( self.s, self.c, self.cref[1], s )
-	      so.p = self
-
-	return so
-end
-
-
---- Object representation of a scheme/config section.
--- @class	module
--- @cstyle	instance
--- @name	luci.uvl.section
-
---- Section instance constructor.
--- @class			function
--- @name			section
--- @param scheme	Scheme instance
--- @param co		Configuration data
--- @param c			Configuration name
--- @param s			Section name
--- @return			Section instance
-section = util.class(uvlitem)
-
-function section.__init__(self, scheme, co, c, s)
-	self.cref = { c, s }
-	self.sref = { c, co and co[s] and co[s]['.type'] or s }
-	self.c    = self:_loadconf(co, c, scheme.configdir)
-	self.s    = scheme
-	self.t    = TYPE_SECTION
-end
-
---- Get all option objects associated with this section.
--- @return	Table containing all associated luci.uvl.option instances
-function section.variables(self)
-	local v = { }
-	if self.s.packages[self.sref[1]].variables[self.sref[2]] then
-		for o, _ in pairs(
-			self.s.packages[self.sref[1]].variables[self.sref[2]]
-		) do
-			v[#v+1] = option(
-				self.s, self.c, self.cref[1], self.cref[2], o
-			)
-		end
-	end
-	return v
-end
-
---- Get an associated option object.
--- @param o	Option to select
--- @return	Option instance
-function section.option(self, o)
-	local oo = option( self.s, self.c, self.cref[1], self.cref[2], o )
-	      oo.p = self
-
-	return oo
-end
-
-
---- Object representation of a scheme/config option.
--- @class	module
--- @cstyle	instance
--- @name	luci.uvl.option
-
---- Section instance constructor.
--- @class			function
--- @name			option
--- @param scheme	Scheme instance
--- @param co		Configuration data
--- @param c			Configuration name
--- @param s			Section name
--- @param o			Option name
--- @return			Option instance
-option = util.class(uvlitem)
-
-function option.__init__(self, scheme, co, c, s, o)
-	self.cref = { c, s, o }
-	self.sref = { c, co and co[s] and co[s]['.type'] or s, o }
-	self.c    = self:_loadconf(co, c, scheme.configdir)
-	self.s    = scheme
-	self.t    = TYPE_OPTION
-end
-
---- Get the value of this option.
--- @return	The associated configuration value
-function option.value(self)
-	local v = self:config() or self:scheme('default')
-	if v and self:scheme('multival') then
-		v = util.split( v, "%s+", nil, true )
-	end
-	return v
-end
-
---- Get the associated section information in scheme.
--- @return	Table containing the scheme properties
-function option.section(self)
-	return self.s.packages[self.sref[1]].sections[self.sref[2]]
-end
-
---- Construct an enum object instance from given or default value.
--- @param v	Value to select
--- @return	Enum instance for selected value
-function option.enum(self, val)
-	return enum(
-		self.s, self.c,
-		self.cref[1], self.cref[2], self.cref[3],
-		val or self:value()
-	)
-end
-
-
---- Object representation of a enum value.
--- @class	module
--- @cstyle	instance
--- @name	luci.uvl.enum
-
---- Section instance constructor.
--- @class			function
--- @name			enum
--- @param scheme	Scheme instance
--- @param co		Configuration data
--- @param c			Configuration name
--- @param s			Section name
--- @param o			Enum name
--- @param v			Enum value
--- @return			Enum value instance
-enum = util.class(option)
-
-function enum.__init__(self, scheme, co, c, s, o, v)
-	self.cref = { c, s, o, v }
-	self.sref = { c, co and co[s] and co[s]['.type'] or s, o, v }
-	self.c    = self:_loadconf(co, c, scheme.configdir)
-	self.s    = scheme
-	self.t    = TYPE_ENUM
-end