libs/uvl/luasrc/uvl.lua

   1 --[[
   2
   3 UCI Validation Layer - Main Library
   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
  18 --- UVL - UCI Validation Layer
  19 -- @class       module
  20 -- @cstyle      instance
  21
  22 local fs = require "nixio.fs"
  23 local uci = require "luci.model.uci"
  24 local util = require "luci.util"
  25 local nutil = require "nixio.util"
  26 local table = require "table"
  27 local string = require "string"
  28
  29 local require, pcall, ipairs, pairs = require, pcall, ipairs, pairs
  30 local type, error, tonumber, tostring = type, error, tonumber, tostring
  31 local unpack, loadfile, collectgarbage = unpack, loadfile, collectgarbage
  32
  33 module "luci.uvl"
  34
  35 local ERR = require "luci.uvl.errors"
  36 local datatypes = require "luci.uvl.datatypes"
  37 local validation = require "luci.uvl.validation"
  38 local dependencies = require "luci.uvl.dependencies"
  39
  40 local TYPE_SCHEME   = 0x00
  41 local TYPE_CONFIG   = 0x01
  42 local TYPE_SECTION  = 0x02
  43 local TYPE_OPTION   = 0x03
  44 local TYPE_ENUM     = 0x04
  45
  46 local PAT_EXPR1         = "^%$?[%w_]+$"
  47 local PAT_EXPR2         = "^%$?[%w_]+%.%$?[%w_]+$"
  48 local PAT_EXPR3         = "^%$?[%w_]+%.%$?[%w_]+%.%$?[%w_]+$"
  49
  50 --- Boolean; default true;
  51 -- treat sections found in config but not in scheme as error
  52 STRICT_UNKNOWN_SECTIONS    = true
  53
  54 --- Boolean; default true;
  55 -- treat options found in config but not in scheme as error
  56 STRICT_UNKNOWN_OPTIONS     = true
  57
  58 --- Boolean; default true;
  59 -- treat failed external validators as error
  60 STRICT_EXTERNAL_VALIDATORS = true
  61
  62 --- Boolean; default true;
  63 -- treat list values stored as options like errors
  64 STRICT_LIST_TYPE           = true
  65
  66
  67 local default_schemedir = "/lib/uci/schema"
  68 local default_savedir = "/tmp/.uvl"
  69
  70
  71 --- Object constructor
  72 -- @class                       function
  73 -- @name                        UVL
  74 -- @param schemedir     Path to the scheme directory (optional)
  75 -- @param configdir     Override config directory (optional)
  76 -- @return                      Instance object
  77 UVL = util.class()
  78
  79 function UVL.__init__( self, schemedir, configdir )
  80         self.schemedir  = schemedir or default_schemedir
  81         self.configdir  = configdir
  82         self.packages   = { }
  83         self.beenthere  = { }
  84         self.depseen    = { }
  85         self.uci                = uci
  86         self.err                = ERR
  87         self.dep                = dependencies
  88         self.datatypes  = datatypes
  89 end
  90
  91
  92 --- Parse given scheme and return the scheme tree.
  93 -- @param scheme        Name of the scheme to parse
  94 -- @return                      Table containing the parsed scheme or nil on error
  95 -- @return                      String containing the reason for errors (if any)
  96 function UVL.get_scheme( self, scheme )
  97         if not self.packages[scheme] then
  98                 local ok, err = self:read_scheme( scheme )
  99                 if not ok then
 100                         return nil, err
 101                 end
 102         end
 103         return self.packages[scheme], nil
 104 end
 105
 106 --- Validate given configuration, section or option.
 107 -- @param config        Name of the configuration to validate
 108 -- @param section       Name of the section to validate (optional)
 109 -- @param option        Name of the option to validate (optional)
 110 -- @return                      Boolean indicating whether the given config validates
 111 -- @return                      String containing the reason for errors (if any)
 112 function UVL.validate( self, config, section, option )
 113         if config and section and option then
 114                 return self:validate_option( config, section, option )
 115         elseif config and section then
 116                 return self:validate_section( config, section )
 117         elseif config then
 118                 return self:validate_config( config )
 119         end
 120 end
 121
 122 --- Validate given configuration.
 123 -- @param cfg   Name of the configuration to validate
 124 -- @return                      Boolean indicating whether the given config validates
 125 -- @return                      String containing the reason for errors (if any)
 126 function UVL.validate_config( self, cfg, uci )
 127
 128         if not self.packages[cfg] then
 129                 local ok, err = self:read_scheme(cfg)
 130                 if not ok then
 131                         return false, err
 132                 end
 133         end
 134
 135         local co = config( self, uci or cfg, uci and cfg )
 136         local sc = { }
 137
 138         self.beenthere = { }
 139         self.depseen   = { }
 140
 141         if not co:config() then
 142                 return false, co:errors()
 143         end
 144
 145         local function _uci_foreach( type, func )
 146                 for k, v in pairs(co:config()) do
 147                         if v['.type'] == type then
 148                                 sc[type] = sc[type] + 1
 149                                 local ok, err = func( k, v )
 150                                 if not ok then co:error(err) end
 151                         end
 152                 end
 153         end
 154
 155         for k, v in pairs( self.packages[cfg].sections ) do
 156                 sc[k] = 0
 157                 _uci_foreach( k,
 158                         function(s)
 159                                 return self:_validate_section( co:section(s) )
 160                         end
 161                 )
 162         end
 163
 164         if STRICT_UNKNOWN_SECTIONS then
 165                 for k, v in pairs(co:config()) do
 166                         local so = co:section(k)
 167                         if not self.beenthere[so:cid()] then
 168                                 co:error(ERR.SECT_UNKNOWN(so))
 169                         end
 170                 end
 171         end
 172
 173         for _, k in ipairs(util.keys(sc)) do
 174                 local so = co:section(k)
 175                 if so:scheme('required') and sc[k] == 0 then
 176                         co:error(ERR.SECT_REQUIRED(so))
 177                 elseif so:scheme('unique') and sc[k] > 1 then
 178                         co:error(ERR.SECT_UNIQUE(so))
 179                 end
 180         end
 181
 182         return co:ok(), co:errors()
 183 end
 184
 185 --- Validate given config section.
 186 -- @param config        Name of the configuration to validate
 187 -- @param section       Name of the section to validate
 188 -- @return                      Boolean indicating whether the given config validates
 189 -- @return                      String containing the reason for errors (if any)
 190 function UVL.validate_section( self, cfg, section, uci )
 191
 192         if not self.packages[cfg] then
 193                 local ok, err = self:read_scheme( cfg )
 194                 if not ok then
 195                         return false, err
 196                 end
 197         end
 198
 199         local co = config( self, uci or cfg, uci and cfg )
 200         local so = co:section( section )
 201
 202         self.beenthere = { }
 203         self.depseen   = { }
 204
 205         if not co:config() then
 206                 return false, co:errors()
 207         end
 208
 209         if so:config() then
 210                 return self:_validate_section( so )
 211         else
 212                 return false, ERR.SECT_NOTFOUND(so)
 213         end
 214 end
 215
 216 --- Validate given config option.
 217 -- @param config        Name of the configuration to validate
 218 -- @param section       Name of the section to validate
 219 -- @param option        Name of the option to validate
 220 -- @return                      Boolean indicating whether the given config validates
 221 -- @return                      String containing the reason for errors (if any)
 222 function UVL.validate_option( self, cfg, section, option, uci )
 223
 224         if not self.packages[cfg] then
 225                 local ok, err = self:read_scheme( cfg )
 226                 if not ok then
 227                         return false, err
 228                 end
 229         end
 230
 231         local co = config( self, uci or cfg, uci and cfg )
 232         local so = co:section( section )
 233         local oo = so:option( option )
 234
 235         if not co:config() then
 236                 return false, co:errors()
 237         end
 238
 239         if so:config() and oo:config() then
 240                 return self:_validate_option( oo )
 241         else
 242                 return false, ERR.OPT_NOTFOUND(oo)
 243         end
 244 end
 245
 246
 247 function UVL._validate_section( self, section )
 248
 249         self.beenthere[section:cid()] = true
 250
 251         if section:config() then
 252                 if section:scheme('named') == true and
 253                    section:config('.anonymous') == true
 254                 then
 255                         return false, ERR.SECT_NAMED(section)
 256                 end
 257
 258                 for _, v in ipairs(section:variables()) do
 259                         local ok, err = self:_validate_option( v )
 260                         if not ok and (
 261                                 v:scheme('required') or v:scheme('type') == "enum" or (
 262                                         not err:is(ERR.ERR_DEP_NOTEQUAL) and
 263                                         not err:is(ERR.ERR_DEP_NOVALUE)
 264                                 )
 265                         ) then
 266                                 section:error(err)
 267                         end
 268                 end
 269
 270                 local ok, err = dependencies.check( self, section )
 271                 if not ok then
 272                         section:error(err)
 273                 end
 274         else
 275                 return false, ERR.SECT_NOTFOUND(section)
 276         end
 277
 278         if STRICT_UNKNOWN_OPTIONS and not section:scheme('dynamic') then
 279                 for k, v in pairs(section:config()) do
 280                         local oo = section:option(k)
 281                         if k:byte(1) == 46 and not self.beenthere[oo:cid()] then
 282                                 section:error(ERR.OPT_UNKNOWN(oo))
 283                         end
 284                 end
 285         end
 286
 287         return section:ok(), section:errors()
 288 end
 289
 290 function UVL._validate_option( self, option, nodeps )
 291
 292         self.beenthere[option:cid()] = true
 293
 294         if not option:scheme() and not option:parent():scheme('dynamic') then
 295                 if STRICT_UNKNOWN_OPTIONS then
 296                         return false, option:error(ERR.OPT_UNKNOWN(option))
 297                 else
 298                         return true
 299                 end
 300
 301         elseif option:scheme() then
 302                 if not nodeps then
 303                         local ok, err = dependencies.check( self, option )
 304                         if not ok then
 305                                 if not err:is_all(
 306                                         ERR.ERR_OPT_REQUIRED,
 307                                         ERR.ERR_DEP_NOTEQUAL,
 308                                         ERR.ERR_DEP_NOVALUE
 309                                 ) then
 310                                         option:error(err)
 311                                         return false, option:errors()
 312                                 else
 313                                         return true
 314                                 end
 315                         end
 316                 end
 317
 318                 if option:scheme('required') and not option:value() then
 319                         return false, option:error(ERR.OPT_REQUIRED(option))
 320
 321                 elseif option:value() then
 322                         local val = option:value()
 323
 324                         if option:scheme('type') == "reference" or
 325                            option:scheme('type') == "enum"
 326                         then
 327                                 local scheme_values = option:scheme('values') or { }
 328                                 local config_values = ( type(val) == "table" and val or { val } )
 329                                 for _, v in ipairs(config_values) do
 330                                         if not scheme_values[v] then
 331                                                 return false, option:error( ERR.OPT_BADVALUE(
 332                                                         option, { v, util.serialize_data(
 333                                                                 util.keys(scheme_values)
 334                                                         ) }
 335                                                 ) )
 336                                         end
 337                                 end
 338                         elseif option:scheme('type') == "list" then
 339                                 if type(val) ~= "table" and STRICT_LIST_TYPE then
 340                                         return false, option:error(ERR.OPT_NOTLIST(option))
 341                                 end
 342                         end
 343
 344                         if option:scheme('datatype') then
 345                                 local dt = option:scheme('datatype')
 346
 347                                 if self.datatypes[dt] then
 348                                         val = ( type(val) == "table" and val or { val } )
 349                                         for i, v in ipairs(val) do
 350                                                 if not self.datatypes[dt]( v ) then
 351                                                         return false, option:error(
 352                                                                 ERR.OPT_INVVALUE(option, { v, dt })
 353                                                         )
 354                                                 end
 355                                         end
 356                                 else
 357                                         return false, option:error(ERR.OPT_DATATYPE(option, dt))
 358                                 end
 359                         end
 360
 361                         val = ( type(val) == "table" and val or { val } )
 362                         for _, v in ipairs(val) do
 363                                 if option:scheme('minlength') then
 364                                         if #v < option:scheme('minlength') then
 365                                                 return false, option:error(ERR.OPT_RANGE(option))
 366                                         end
 367                                 end
 368
 369                                 if option:scheme('maxlength') then
 370                                         if #v > option:scheme('maxlength') then
 371                                                 return false, option:error(ERR.OPT_RANGE(option))
 372                                         end
 373                                 end
 374
 375                                 local w = tonumber(v)
 376
 377                                 if option:scheme('minimum') then
 378                                         if not w or w < option:scheme('minimum') then
 379                                                 return false, option:error(ERR.OPT_RANGE(option))
 380                                         end
 381                                 end
 382
 383                                 if option:scheme('maximum') then
 384                                         if not w or w > option:scheme('maximum') then
 385                                                 return false, option:error(ERR.OPT_RANGE(option))
 386                                         end
 387                                 end
 388                         end
 389                 end
 390
 391                 local ok, err = validation.check( self, option )
 392                 if not ok and STRICT_EXTERNAL_VALIDATORS then
 393                         return false, option:error(err)
 394                 end
 395         end
 396
 397         return option:ok(), option:errors()
 398 end
 399
 400 --- Find all parts of given scheme and construct validation tree.
 401 -- This is normally done on demand, so you don't have to call this function
 402 -- by yourself.
 403 -- @param shm   Name of the scheme to parse
 404 -- @param alias         Create an alias for the loaded scheme
 405 function UVL.read_scheme( self, shm, alias )
 406
 407         local so = scheme( self, shm )
 408         local bc = "%s/bytecode/%s.lua" %{ self.schemedir, shm }
 409
 410         if not fs.access(bc) then
 411                 local files = nutil.consume((fs.glob(self.schemedir .. '/*/' .. shm)))
 412
 413                 if #files > 0 then
 414                         local ok, err
 415                         for _, file in ipairs(files) do
 416                                 if not fs.access(file) then
 417                                         return false, so:error(ERR.SME_READ(so,file))
 418                                 end
 419
 420                                 local uci = uci.cursor( fs.dirname(file), default_savedir )
 421
 422                                 local sname = fs.basename(file)
 423                                 local sd, err = uci:load( sname )
 424
 425                                 if not sd then
 426                                         return false, ERR.UCILOAD(so, err)
 427                                 end
 428
 429                                 ok, err = pcall(function()
 430                                         uci:foreach(sname, "package", function(s)
 431                                                 self:_parse_package(so, s[".name"], s)
 432                                         end)
 433                                         uci:foreach(sname, "section", function(s)
 434                                                 self:_parse_section(so, s[".name"], s)
 435                                         end)
 436                                         uci:foreach(sname, "variable", function(s)
 437                                                 self:_parse_var(so, s[".name"], s)
 438                                         end)
 439                                         uci:foreach(sname, "enum", function(s)
 440                                                 self:_parse_enum(so, s[".name"], s)
 441                                         end)
 442
 443                                 end)
 444                         end
 445
 446                         if ok and alias then self.packages[alias] = self.packages[shm] end
 447                         return ok and self, err
 448                 else
 449                         return false, so:error(ERR.SME_FIND(so, self.schemedir))
 450                 end
 451         else
 452                 local sc = loadfile(bc)
 453                 if sc then
 454                         self.packages[shm] = sc()
 455                         return true
 456                 else
 457                         return false, so:error(ERR.SME_READ(so,bc))
 458                 end
 459         end
 460 end
 461
 462 -- helper function to check for required fields
 463 local function _req( t, n, c, r )
 464         for i, v in ipairs(r) do
 465                 if not c[v] then
 466                         local p, o = scheme:sid(), nil
 467
 468                         if t == TYPE_SECTION then
 469                                 o = section( scheme, nil, p, n )
 470                         elseif t == TYPE_OPTION then
 471                                 o = option( scheme, nil, p, '(nil)', n )
 472                         elseif t == TYPE_ENUM then
 473                                 o = enum( scheme, nil, p, '(nil)', '(nil)', n )
 474                         end
 475
 476                         return false, ERR.SME_REQFLD(o,v)
 477                 end
 478         end
 479         return true
 480 end
 481
 482 -- helper function to validate references
 483 local function _ref( c, t )
 484         local r, k, n = {}
 485         if c == TYPE_SECTION then
 486                 k = "package"
 487                 n = 1
 488         elseif c == TYPE_OPTION then
 489                 k = "section"
 490                 n = 2
 491         elseif c == TYPE_ENUM then
 492                 k = "variable"
 493                 n = 3
 494         end
 495
 496         for o in t[k]:gmatch("[^.]+") do
 497                 r[#r+1] = o
 498         end
 499         r[1] = ( #r[1] > 0 and r[1] or scheme:sid() )
 500
 501         if #r ~= n then
 502                 return false, ERR.SME_BADREF(scheme, k)
 503         end
 504
 505         return r
 506 end
 507
 508 -- helper function to read bools
 509 local function _bool( v )
 510         return ( v == "true" or v == "yes" or v == "on" or v == "1" )
 511 end
 512
 513 -- Step 0: get package meta information
 514 function UVL._parse_package(self, scheme, k, v)
 515         local sid = scheme:sid()
 516         local pkg = self.packages[sid] or {
 517                 ["name"]      = sid;
 518                 ["sections"]  = { };
 519                 ["variables"] = { };
 520         }
 521
 522         pkg.title = v.title
 523         pkg.description = v.description
 524
 525         self.packages[sid] = pkg
 526 end
 527
 528 -- Step 1: get all sections
 529 function UVL._parse_section(self, scheme, k, v)
 530         local ok, err = _req( TYPE_SECTION, k, v, { "name", "package" } )
 531         if err then error(scheme:error(err)) end
 532
 533         local r, err = _ref( TYPE_SECTION, v )
 534         if err then error(scheme:error(err)) end
 535
 536         local p = self.packages[r[1]] or {
 537                 ["name"]      = r[1];
 538                 ["sections"]  = { };
 539                 ["variables"] = { };
 540         }
 541         p.sections[v.name]  = p.sections[v.name]  or { }
 542         p.variables[v.name] = p.variables[v.name] or { }
 543         self.packages[r[1]] = p
 544
 545         local s  = p.sections[v.name]
 546         local so = scheme:section(v.name)
 547
 548         for k, v2 in pairs(v) do
 549                 if k ~= "name" and k ~= "package" and k:byte(1) == 46 then
 550                         if k == "depends" then
 551                                 s.depends = self:_read_dependency( v2, s.depends )
 552                                 if not s.depends then
 553                                         return false, scheme:error(
 554                                                 ERR.SME_BADDEP(so, util.serialize_data(s.depends))
 555                                         )
 556                                 end
 557                         elseif k == "dynamic" or k == "unique" or
 558                                k == "required" or k == "named"
 559                         then
 560                                 s[k] = _bool(v2)
 561                         else
 562                                 s[k] = v2
 563                         end
 564                 end
 565         end
 566
 567         s.dynamic  = s.dynamic  or false
 568         s.unique   = s.unique   or false
 569         s.required = s.required or false
 570         s.named    = s.named    or false
 571 end
 572
 573 -- Step 2: get all variables
 574 function UVL._parse_var(self, scheme, k, v)
 575         local ok, err = _req( TYPE_OPTION, k, v, { "name", "section" } )
 576         if err then error(scheme:error(err)) end
 577
 578         local r, err = _ref( TYPE_OPTION, v )
 579         if err then error(scheme:error(err)) end
 580
 581         local p = self.packages[r[1]]
 582         if not p then
 583                 error(scheme:error(
 584                         ERR.SME_VBADPACK({scheme:sid(), '', v.name}, r[1])
 585                 ))
 586         end
 587
 588         local s = p.variables[r[2]]
 589         if not s then
 590                 error(scheme:error(
 591                         ERR.SME_VBADSECT({scheme:sid(), '', v.name}, r[2])
 592                 ))
 593         end
 594
 595         s[v.name] = s[v.name] or { }
 596
 597         local t  = s[v.name]
 598         local so = scheme:section(r[2])
 599         local to = so:option(v.name)
 600
 601         for k, v2 in pairs(v) do
 602                 if k ~= "name" and k ~= "section" and k:byte(1) == 46 then
 603                         if k == "depends" then
 604                                 t.depends = self:_read_dependency( v2, t.depends )
 605                                 if not t.depends then
 606                                         error(scheme:error(so:error(
 607                                                 ERR.SME_BADDEP(to, util.serialize_data(v2))
 608                                         )))
 609                                 end
 610                         elseif k == "validator" then
 611                                 t.validators = self:_read_validator( v2, t.validators )
 612                                 if not t.validators then
 613                                         error(scheme:error(so:error(
 614                                                 ERR.SME_BADVAL(to, util.serialize_data(v2))
 615                                         )))
 616                                 end
 617                         elseif k == "valueof" then
 618                                 local values, err = self:_read_reference( v2 )
 619                                 if err then
 620                                         error(scheme:error(so:error(
 621                                                 ERR.REFERENCE(to, util.serialize_data(v2)):child(err)
 622                                         )))
 623                                 end
 624                                 t.type   = "reference"
 625                                 t.values = values
 626                                 t.valueof = type(v2) == "table" and v2 or {v2}
 627                         elseif k == "required" then
 628                                 t[k] = _bool(v2)
 629                         elseif k == "minlength" or k == "maxlength" or
 630                    k == "minimum" or k == "maximum"
 631             then
 632                                 t[k] = tonumber(v2)
 633                         else
 634                                 t[k] = t[k] or v2
 635                         end
 636                 end
 637         end
 638
 639         t.type     = t.type     or "variable"
 640         t.datatype = t.datatype or "string"
 641         t.required = t.required or false
 642 end
 643
 644 -- Step 3: get all enums
 645 function UVL._parse_enum(self, scheme, k, v)
 646         local ok, err = _req( TYPE_ENUM, k, v, { "value", "variable" } )
 647         if err then error(scheme:error(err)) end
 648
 649         local r, err = _ref( TYPE_ENUM, v )
 650         if err then error(scheme:error(err)) end
 651
 652         local p = self.packages[r[1]]
 653         if not p then
 654                 error(scheme:error(
 655                         ERR.SME_EBADPACK({scheme:sid(), '', '', v.value}, r[1])
 656                 ))
 657         end
 658
 659         local s = p.variables[r[2]]
 660         if not s then
 661                 error(scheme:error(
 662                         ERR.SME_EBADSECT({scheme:sid(), '', '', v.value}, r[2])
 663                 ))
 664         end
 665
 666         local t = s[r[3]]
 667         if not t then
 668                 error(scheme:error(
 669                         ERR.SME_EBADOPT({scheme:sid(), '', '', v.value}, r[3])
 670                 ))
 671         end
 672
 673
 674         local so = scheme:section(r[2])
 675         local oo = so:option(r[3])
 676         local eo = oo:enum(v.value)
 677
 678         if t.type ~= "enum" and t.type ~= "reference" then
 679                 error(scheme:error(ERR.SME_EBADTYPE(eo)))
 680         end
 681
 682         if not t.values then
 683                 t.values = { [v.value] = v.title or v.value }
 684                 t.valuelist = { {value = v.value, title = v.title} }
 685         else
 686                 t.values[v.value] = v.title or v.value
 687                 t.valuelist[#t.valuelist + 1] = {value = v.value, title = v.title}
 688         end
 689
 690         if not t.enum_depends then
 691                 t.enum_depends = { }
 692         end
 693
 694         if v.default then
 695                 if t.default then
 696                         error(scheme:error(ERR.SME_EBADDEF(eo)))
 697                 end
 698                 t.default = v.value
 699         end
 700
 701         if v.depends then
 702                 t.enum_depends[v.value] = self:_read_dependency(
 703                         v.depends, t.enum_depends[v.value]
 704                 )
 705
 706                 if not t.enum_depends[v.value] then
 707                         error(scheme:error(so:error(oo:error(
 708                                 ERR.SME_BADDEP(eo, util.serialize_data(v.depends))
 709                         ))))
 710                 end
 711         end
 712 end
 713
 714 -- Read a dependency specification
 715 function UVL._read_dependency( self, values, deps )
 716         local expr = "%$?[%w_]+"
 717         if values then
 718                 values = ( type(values) == "table" and values or { values } )
 719                 for _, value in ipairs(values) do
 720                         local condition = { }
 721                         for val in value:gmatch("[^,]+") do
 722                                 local k, e, v = val:match("%s*([%w$_.]+)%s*(=?)%s*(.*)")
 723
 724                                 if k and (
 725                                         k:match(PAT_EXPR1) or k:match(PAT_EXPR2) or k:match(PAT_EXPR3)
 726                                 ) then
 727                                         condition[k] = (e == '=') and v or true
 728                                 else
 729                                         return nil
 730                                 end
 731                         end
 732
 733                         if not deps then
 734                                 deps = { condition }
 735                         else
 736                                 deps[#deps+1] = condition
 737                         end
 738                 end
 739         end
 740
 741         return deps
 742 end
 743
 744 -- Read a validator specification
 745 function UVL._read_validator( self, values, validators )
 746         if values then
 747                 values = ( type(values) == "table" and values or { values } )
 748                 for _, value in ipairs(values) do
 749                         local validator
 750
 751                         if value:match("^exec:") then
 752                                 validator = value:gsub("^exec:","")
 753                         elseif value:match("^lua:") then
 754                                 validator = self:_resolve_function( (value:gsub("^lua:","") ) )
 755                         elseif value:match("^regexp:") then
 756                                 local pattern = value:gsub("^regexp:","")
 757                                 validator = function( type, dtype, pack, sect, optn, arg1, arg2, arg3, arg4, arg5 )
 758                                         local values = { arg1, arg2, arg3, arg4, arg5 }
 759                                         for _, v in ipairs(values) do
 760                                                 local ok, match =
 761                                                         pcall( string.match, v, pattern )
 762
 763                                                 if not ok then
 764                                                         return false, match
 765                                                 elseif not match then
 766                                                         return false,
 767                                                                 'Value "%s" does not match pattern "%s"' % {
 768                                                                         v, pattern
 769                                                                 }
 770                                                 end
 771                                         end
 772                                         return true
 773                                 end
 774                         end
 775
 776                         if validator then
 777                                 if not validators then
 778                                         validators = { validator }
 779                                 else
 780                                         validators[#validators+1] = validator
 781                                 end
 782                         else
 783                                 return nil
 784                         end
 785                 end
 786
 787                 return validators
 788         end
 789 end
 790
 791 -- Read a reference specification (XXX: We should validate external configs too...)
 792 function UVL._read_reference( self, values )
 793         local val = { }
 794         values = ( type(values) == "table" and values or { values } )
 795
 796         for _, value in ipairs(values) do
 797                 local ref = util.split(value, ".")
 798
 799                 if #ref == 2 or #ref == 3 then
 800                         local co = config( self, ref[1] )
 801                         if not co:config() then return false, co:errors() end
 802
 803                         for k, v in pairs(co:config()) do
 804                                 if v['.type'] == ref[2] then
 805                                         if #ref == 2 then
 806                                                 if v['.anonymous'] == true then
 807                                                         return false, ERR.SME_INVREF('', value)
 808                                                 end
 809                                                 val[k] = k      -- XXX: title/description would be nice
 810                                         elseif v[ref[3]] then
 811                                                 val[v[ref[3]]] = v[ref[3]]  -- XXX: dito
 812                                         end
 813                                 end
 814                         end
 815                 else
 816                         return false, ERR.SME_BADREF('', value)
 817                 end
 818         end
 819
 820         return val, nil
 821 end
 822
 823 -- Resolve given path
 824 function UVL._resolve_function( self, value )
 825         local path = util.split(value, ".")
 826
 827         for i=1, #path-1 do
 828                 local stat, mod = pcall(
 829                         require, table.concat(path, ".", 1, i)
 830                 )
 831
 832                 if stat and mod then
 833                         for j=i+1, #path-1 do
 834                                 if not type(mod) == "table" then
 835                                         break
 836                                 end
 837                                 mod = mod[path[j]]
 838                                 if not mod then
 839                                         break
 840                                 end
 841                         end
 842                         mod = type(mod) == "table" and mod[path[#path]] or nil
 843                         if type(mod) == "function" then
 844                                 return mod
 845                         end
 846                 end
 847         end
 848 end
 849
 850
 851 --- Object representation of an uvl item - base class.
 852 uvlitem = util.class()
 853
 854 function uvlitem.cid(self)
 855         if #self.cref == 1 then
 856                 return self.cref[1]
 857         else
 858                 local r = { unpack(self.cref) }
 859                 local c = self.c
 860                 if c and c[r[2]] and c[r[2]]['.anonymous'] and c[r[2]]['.index'] then
 861                         r[2] = '@' .. c[r[2]]['.type'] ..
 862                                    '[' .. tostring(c[r[2]]['.index']) .. ']'
 863                 end
 864                 return table.concat( r, '.' )
 865         end
 866 end
 867
 868 function uvlitem.sid(self)
 869         return table.concat( self.sref, '.' )
 870 end
 871
 872 function uvlitem.scheme(self, opt)
 873         local s = self.s and self.s.packages
 874         s = s      and s[self.sref[1]]
 875         if #self.sref == 4 or #self.sref == 3 then
 876                 s = s      and s.variables
 877                 s = s      and s[self.sref[2]]
 878                 s = s      and s[self.sref[3]]
 879         elseif #self.sref == 2 then
 880                 s = s      and s.sections
 881                 s = s      and s[self.sref[2]]
 882         end
 883
 884         if s and opt then
 885                 return s[opt]
 886         elseif s then
 887                 return s
 888         end
 889 end
 890
 891 function uvlitem.config(self, opt)
 892         local c = self.c
 893
 894         if #self.cref >= 2 and #self.cref <= 4 then
 895                 c = c and self.c[self.cref[2]] or nil
 896                 if #self.cref >= 3 then
 897                         c = c and c[self.cref[3]] or nil
 898                 end
 899         end
 900
 901         if c and opt then
 902                 return c[opt]
 903         elseif c then
 904                 return c
 905         end
 906 end
 907
 908 function uvlitem.title(self)
 909         return self:scheme() and self:scheme('title') or
 910                 self.cref[3] or self.cref[2] or self.cref[1]
 911 end
 912
 913 function uvlitem.type(self)
 914         if self.t == TYPE_CONFIG then
 915                 return 'config'
 916         elseif self.t == TYPE_SECTION then
 917                 return 'section'
 918         elseif self.t == TYPE_OPTION then
 919                 return 'option'
 920         elseif self.t == TYPE_ENUM then
 921                 return 'enum'
 922         end
 923 end
 924
 925 function uvlitem.error(self, arg1, arg2, arg3, arg4, arg5)
 926         if not self.e then
 927                 local errconst = { ERR.CONFIG, ERR.SECTION, ERR.OPTION, ERR.OPTION }
 928                 self.e = errconst[#self.cref]( self )
 929         end
 930
 931         return self.e:child( arg1, arg2, arg3, arg4, arg5 )
 932 end
 933
 934 function uvlitem.errors(self)
 935         return self.e
 936 end
 937
 938 function uvlitem.ok(self)
 939         return not self:errors()
 940 end
 941
 942 function uvlitem.parent(self)
 943         if self.p then
 944                 return self.p
 945         elseif #self.cref == 3 or #self.cref == 4 then
 946                 return section( self.s, self.c, self.cref[1], self.cref[2] )
 947         elseif #self.cref == 2 then
 948                 return config( self.s, self.c, self.cref[1] )
 949         else
 950                 return nil
 951         end
 952 end
 953
 954 function uvlitem._loadconf(self, co, c, configdir)
 955         co = co or self._configcache
 956         if not co then
 957                 local err
 958                 co, err = uci.cursor(configdir):get_all(c)
 959
 960                 if err then
 961                         self:error(ERR.UCILOAD(self, err))
 962                 end
 963
 964                 self._configcache = co
 965         end
 966         return co
 967 end
 968
 969
 970 --- Object representation of a scheme.
 971 -- @class       scheme
 972 -- @cstyle      instance
 973 -- @name        luci.uvl.scheme
 974
 975 --- Scheme instance constructor.
 976 -- @class                       function
 977 -- @name                        scheme
 978 -- @param scheme        Scheme instance
 979 -- @param co            Configuration data
 980 -- @param c                     Configuration name
 981 -- @return                      Config instance
 982 scheme = util.class(uvlitem)
 983
 984 function scheme.__init__(self, scheme, co, c)
 985         if not c then
 986                 c, co = co, nil
 987         end
 988
 989         self.cref = { c }
 990         self.sref = { c }
 991         self.c    = self:_loadconf(co, c, scheme.configdir)
 992         self.s    = scheme
 993         self.t    = TYPE_SCHEME
 994 end
 995
 996 --- Add an error to scheme.
 997 -- @return      Scheme error context
 998 function scheme.error(self, arg1, arg2, arg3, arg4, arg5)
 999         if not self.e then self.e = ERR.SCHEME( self ) end
1000         return self.e:child( arg1, arg2, arg3, arg4, arg5 )
1001 end
1002
1003 --- Get an associated config object.
1004 -- @return      Config instance
1005 function scheme.config(self)
1006         local co = config( self.s, self.cref[1] )
1007               co.p = self
1008
1009         return co
1010 end
1011
1012 --- Get all section objects associated with this scheme.
1013 -- @return      Table containing all associated luci.uvl.section instances
1014 function scheme.sections(self)
1015         local v = { }
1016         if self.s.packages[self.sref[1]].sections then
1017                 for o, _ in pairs( self.s.packages[self.sref[1]].sections ) do
1018                         v[#v+1] = option(
1019                                 self.s, self.c, self.cref[1], self.cref[2], o
1020                         )
1021                 end
1022         end
1023         return v
1024 end
1025
1026 --- Get an associated section object.
1027 -- @param s     Section to select
1028 -- @return      Section instance
1029 function scheme.section(self, s)
1030         local so = section( self.s, self.c, self.cref[1], s )
1031               so.p = self
1032
1033         return so
1034 end
1035
1036
1037 --- Object representation of a config.
1038 -- @class       config
1039 -- @cstyle      instance
1040 -- @name        luci.uvl.config
1041
1042 --- Config instance constructor.
1043 -- @class                       function
1044 -- @name                        config
1045 -- @param scheme        Scheme instance
1046 -- @param co            Configuration data
1047 -- @param c                     Configuration name
1048 -- @return                      Config instance
1049 config = util.class(uvlitem)
1050
1051 function config.__init__(self, scheme, co, c)
1052         if not c then
1053                 c, co = co, nil
1054         end
1055         self.cref = { c }
1056         self.sref = { c }
1057         self.c    = self:_loadconf(co, c, scheme.configdir)
1058         self.s    = scheme
1059         self.t    = TYPE_CONFIG
1060 end
1061
1062 --- Get all section objects associated with this config.
1063 -- @return      Table containing all associated luci.uvl.section instances
1064 function config.sections(self)
1065         local v = { }
1066         if self.s.packages[self.sref[1]].sections then
1067                 for o, _ in pairs( self.s.packages[self.sref[1]].sections ) do
1068                         v[#v+1] = option(
1069                                 self.s, self.c, self.cref[1], self.cref[2], o
1070                         )
1071                 end
1072         end
1073         return v
1074 end
1075
1076 --- Get an associated section object.
1077 -- @param s     Section to select
1078 -- @return      Section instance
1079 function config.section(self, s)
1080         local so = section( self.s, self.c, self.cref[1], s )
1081               so.p = self
1082
1083         return so
1084 end
1085
1086
1087 --- Object representation of a scheme/config section.
1088 -- @class       module
1089 -- @cstyle      instance
1090 -- @name        luci.uvl.section
1091
1092 --- Section instance constructor.
1093 -- @class                       function
1094 -- @name                        section
1095 -- @param scheme        Scheme instance
1096 -- @param co            Configuration data
1097 -- @param c                     Configuration name
1098 -- @param s                     Section name
1099 -- @return                      Section instance
1100 section = util.class(uvlitem)
1101
1102 function section.__init__(self, scheme, co, c, s)
1103         self.cref = { c, s }
1104         self.sref = { c, co and co[s] and co[s]['.type'] or s }
1105         self.c    = self:_loadconf(co, c, scheme.configdir)
1106         self.s    = scheme
1107         self.t    = TYPE_SECTION
1108 end
1109
1110 --- Get all option objects associated with this section.
1111 -- @return      Table containing all associated luci.uvl.option instances
1112 function section.variables(self)
1113         local v = { }
1114         if self.s.packages[self.sref[1]].variables[self.sref[2]] then
1115                 for o, _ in pairs(
1116                         self.s.packages[self.sref[1]].variables[self.sref[2]]
1117                 ) do
1118                         v[#v+1] = option(
1119                                 self.s, self.c, self.cref[1], self.cref[2], o
1120                         )
1121                 end
1122         end
1123         return v
1124 end
1125
1126 --- Get an associated option object.
1127 -- @param o     Option to select
1128 -- @return      Option instance
1129 function section.option(self, o)
1130         local oo = option( self.s, self.c, self.cref[1], self.cref[2], o )
1131               oo.p = self
1132
1133         return oo
1134 end
1135
1136
1137 --- Object representation of a scheme/config option.
1138 -- @class       module
1139 -- @cstyle      instance
1140 -- @name        luci.uvl.option
1141
1142 --- Section instance constructor.
1143 -- @class                       function
1144 -- @name                        option
1145 -- @param scheme        Scheme instance
1146 -- @param co            Configuration data
1147 -- @param c                     Configuration name
1148 -- @param s                     Section name
1149 -- @param o                     Option name
1150 -- @return                      Option instance
1151 option = util.class(uvlitem)
1152
1153 function option.__init__(self, scheme, co, c, s, o)
1154         self.cref = { c, s, o }
1155         self.sref = { c, co and co[s] and co[s]['.type'] or s, o }
1156         self.c    = self:_loadconf(co, c, scheme.configdir)
1157         self.s    = scheme
1158         self.t    = TYPE_OPTION
1159 end
1160
1161 --- Get the value of this option.
1162 -- @return      The associated configuration value
1163 function option.value(self)
1164         local v = self:config() or self:scheme('default')
1165         if v and self:scheme('multival') then
1166                 v = util.split( v, "%s+", nil, true )
1167         end
1168         return v
1169 end
1170
1171 --- Get the associated section information in scheme.
1172 -- @return      Table containing the scheme properties
1173 function option.section(self)
1174         return self.s.packages[self.sref[1]].sections[self.sref[2]]
1175 end
1176
1177 --- Construct an enum object instance from given or default value.
1178 -- @param v     Value to select
1179 -- @return      Enum instance for selected value
1180 function option.enum(self, val)
1181         return enum(
1182                 self.s, self.c,
1183                 self.cref[1], self.cref[2], self.cref[3],
1184                 val or self:value()
1185         )
1186 end
1187
1188
1189 --- Object representation of a enum value.
1190 -- @class       module
1191 -- @cstyle      instance
1192 -- @name        luci.uvl.enum
1193
1194 --- Section instance constructor.
1195 -- @class                       function
1196 -- @name                        enum
1197 -- @param scheme        Scheme instance
1198 -- @param co            Configuration data
1199 -- @param c                     Configuration name
1200 -- @param s                     Section name
1201 -- @param o                     Enum name
1202 -- @param v                     Enum value
1203 -- @return                      Enum value instance
1204 enum = util.class(option)
1205
1206 function enum.__init__(self, scheme, co, c, s, o, v)
1207         self.cref = { c, s, o, v }
1208         self.sref = { c, co and co[s] and co[s]['.type'] or s, o, v }
1209         self.c    = self:_loadconf(co, c, scheme.configdir)
1210         self.s    = scheme
1211         self.t    = TYPE_ENUM
1212 end