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 module( "luci.uvl", package.seeall )
  23
  24 require("luci.fs")
  25 require("luci.util")
  26 local uci = require("luci.model.uci")
  27 require("luci.uvl.errors")
  28 require("luci.uvl.datatypes")
  29 require("luci.uvl.validation")
  30 require("luci.uvl.dependencies")
  31
  32 local cursor = uci.cursor()
  33
  34 TYPE_SCHEME   = 0x00
  35 TYPE_CONFIG   = 0x01
  36 TYPE_SECTION  = 0x02
  37 TYPE_OPTION   = 0x03
  38 TYPE_ENUM     = 0x04
  39
  40 --- Boolean; default true;
  41 -- treat sections found in config but not in scheme as error
  42 STRICT_UNKNOWN_SECTIONS    = true
  43
  44 --- Boolean; default true;
  45 -- treat options found in config but not in scheme as error
  46 STRICT_UNKNOWN_OPTIONS     = true
  47
  48 --- Boolean; default true;
  49 -- treat failed external validators as error
  50 STRICT_EXTERNAL_VALIDATORS = true
  51
  52 --- Boolean; default true;
  53 -- treat list values stored as options like errors
  54 STRICT_LIST_TYPE           = true
  55
  56
  57 local default_schemedir = "/lib/uci/schema"
  58 local default_savedir = "/tmp/.uvl"
  59 local ERR = luci.uvl.errors
  60
  61
  62 --- Object constructor
  63 -- @class                       function
  64 -- @name                        UVL
  65 -- @param schemedir     Path to the scheme directory (optional)
  66 -- @return                      Instance object
  67 UVL = luci.util.class()
  68
  69 function UVL.__init__( self, schemedir )
  70         self.schemedir  = schemedir or default_schemedir
  71         self.packages   = { }
  72         self.beenthere  = { }
  73         self.depseen    = { }
  74         self.uci                = luci.model.uci
  75         self.err                = luci.uvl.errors
  76         self.dep                = luci.uvl.dependencies
  77         self.datatypes  = luci.uvl.datatypes
  78 end
  79
  80
  81 --- Parse given scheme and return the scheme tree.
  82 -- @param scheme        Name of the scheme to parse
  83 -- @return                      Table containing the parsed scheme or nil on error
  84 -- @return                      String containing the reason for errors (if any)
  85 function UVL.get_scheme( self, scheme )
  86         if not self.packages[scheme] then
  87                 local ok, err = self:read_scheme( scheme )
  88                 if not ok then
  89                         return nil, err
  90                 end
  91         end
  92         return self.packages[scheme], nil
  93 end
  94
  95 --- Validate given configuration, section or option.
  96 -- @param config        Name of the configuration to validate
  97 -- @param section       Name of the section to validate (optional)
  98 -- @param option        Name of the option to validate (optional)
  99 -- @return                      Boolean indicating whether the given config validates
 100 -- @return                      String containing the reason for errors (if any)
 101 function UVL.validate( self, config, section, option )
 102         if config and section and option then
 103                 return self:validate_option( config, section, option )
 104         elseif config and section then
 105                 return self:validate_section( config, section )
 106         elseif config then
 107                 return self:validate_config( config )
 108         end
 109 end
 110
 111 --- Validate given configuration.
 112 -- @param config        Name of the configuration to validate
 113 -- @return                      Boolean indicating whether the given config validates
 114 -- @return                      String containing the reason for errors (if any)
 115 function UVL.validate_config( self, config, uci )
 116
 117         if not self.packages[config] then
 118                 local ok, err = self:read_scheme(config)
 119                 if not ok then
 120                         return false, err
 121                 end
 122         end
 123
 124         local co = luci.uvl.config( self, uci or config, uci and config )
 125         local sc = { }
 126
 127         self.beenthere = { }
 128         self.depseen   = { }
 129
 130         if not co:config() then
 131                 return false, co:errors()
 132         end
 133
 134         local function _uci_foreach( type, func )
 135                 for k, v in pairs(co:config()) do
 136                         if v['.type'] == type then
 137                                 sc[type] = sc[type] + 1
 138                                 local ok, err = func( k, v )
 139                                 if not ok then co:error(err) end
 140                         end
 141                 end
 142         end
 143
 144         for k, v in pairs( self.packages[config].sections ) do
 145                 sc[k] = 0
 146                 _uci_foreach( k,
 147                         function(s)
 148                                 return self:_validate_section( co:section(s) )
 149                         end
 150                 )
 151         end
 152
 153         if STRICT_UNKNOWN_SECTIONS then
 154                 for k, v in pairs(co:config()) do
 155                         local so = co:section(k)
 156                         if not self.beenthere[so:cid()] then
 157                                 co:error(ERR.SECT_UNKNOWN(so))
 158                         end
 159                 end
 160         end
 161
 162         for _, k in ipairs(luci.util.keys(sc)) do
 163                 local so = co:section(k)
 164                 if so:scheme('required') and sc[k] == 0 then
 165                         co:error(ERR.SECT_REQUIRED(so))
 166                 elseif so:scheme('unique') and sc[k] > 1 then
 167                         co:error(ERR.SECT_UNIQUE(so))
 168                 end
 169         end
 170
 171         return co:ok(), co:errors()
 172 end
 173
 174 --- Validate given config section.
 175 -- @param config        Name of the configuration to validate
 176 -- @param section       Name of the section to validate
 177 -- @return                      Boolean indicating whether the given config validates
 178 -- @return                      String containing the reason for errors (if any)
 179 function UVL.validate_section( self, config, section, uci )
 180
 181         if not self.packages[config] then
 182                 local ok, err = self:read_scheme( config )
 183                 if not ok then
 184                         return false, err
 185                 end
 186         end
 187
 188         local co = luci.uvl.config( self, uci or config, uci and config )
 189         local so = co:section( section )
 190
 191         self.beenthere = { }
 192         self.depseen   = { }
 193
 194         if not co:config() then
 195                 return false, co:errors()
 196         end
 197
 198         if so:config() then
 199                 return self:_validate_section( so )
 200         else
 201                 return false, ERR.SECT_NOTFOUND(so)
 202         end
 203 end
 204
 205 --- Validate given config option.
 206 -- @param config        Name of the configuration to validate
 207 -- @param section       Name of the section to validate
 208 -- @param option        Name of the option to validate
 209 -- @return                      Boolean indicating whether the given config validates
 210 -- @return                      String containing the reason for errors (if any)
 211 function UVL.validate_option( self, config, section, option, uci )
 212
 213         if not self.packages[config] then
 214                 local ok, err = self:read_scheme( config )
 215                 if not ok then
 216                         return false, err
 217                 end
 218         end
 219
 220         local co = luci.uvl.config( self, uci or config, uci and config )
 221         local so = co:section( section )
 222         local oo = so:option( option )
 223
 224         if not co:config() then
 225                 return false, co:errors()
 226         end
 227
 228         if so:config() and oo:config() then
 229                 return self:_validate_option( oo )
 230         else
 231                 return false, ERR.OPT_NOTFOUND(oo)
 232         end
 233 end
 234
 235
 236 function UVL._validate_section( self, section )
 237
 238         self.beenthere[section:cid()] = true
 239
 240         if section:config() then
 241                 if section:scheme('named') == true and
 242                    section:config('.anonymous') == true
 243                 then
 244                         return false, ERR.SECT_NAMED(section)
 245                 end
 246
 247                 for _, v in ipairs(section:variables()) do
 248                         local ok, err = self:_validate_option( v )
 249                         if not ok and (
 250                                 v:scheme('required') or v:scheme('type') == "enum" or (
 251                                         not err:is(ERR.ERR_DEP_NOTEQUAL) and
 252                                         not err:is(ERR.ERR_DEP_NOVALUE)
 253                                 )
 254                         ) then
 255                                 section:error(err)
 256                         end
 257                 end
 258
 259                 local ok, err = luci.uvl.dependencies.check( self, section )
 260                 if not ok then
 261                         section:error(err)
 262                 end
 263         else
 264                 return false, ERR.SECT_NOTFOUND(section)
 265         end
 266
 267         if STRICT_UNKNOWN_OPTIONS and not section:scheme('dynamic') then
 268                 for k, v in pairs(section:config()) do
 269                         local oo = section:option(k)
 270                         if k:sub(1,1) ~= "." and not self.beenthere[oo:cid()] then
 271                                 section:error(ERR.OPT_UNKNOWN(oo))
 272                         end
 273                 end
 274         end
 275
 276         return section:ok(), section:errors()
 277 end
 278
 279 function UVL._validate_option( self, option, nodeps )
 280
 281         self.beenthere[option:cid()] = true
 282
 283         if not option:scheme() and not option:parent():scheme('dynamic') then
 284                 if STRICT_UNKNOWN_OPTIONS then
 285                         return false, option:error(ERR.OPT_UNKNOWN(option))
 286                 else
 287                         return true
 288                 end
 289
 290         elseif option:scheme() then
 291                 if option:scheme('required') and not option:value() then
 292                         return false, option:error(ERR.OPT_REQUIRED(option))
 293
 294                 elseif option:value() then
 295                         local val = option:value()
 296
 297                         if option:scheme('type') == "reference" or
 298                            option:scheme('type') == "enum"
 299                         then
 300                                 local scheme_values = option:scheme('values') or { }
 301                                 local config_values = ( type(val) == "table" and val or { val } )
 302                                 for _, v in ipairs(config_values) do
 303                                         if not scheme_values[v] then
 304                                                 return false, option:error( ERR.OPT_BADVALUE(
 305                                                         option, { v, luci.util.serialize_data(
 306                                                                 luci.util.keys(scheme_values)
 307                                                         ) }
 308                                                 ) )
 309                                         end
 310                                 end
 311                         elseif option:scheme('type') == "list" then
 312                                 if type(val) ~= "table" and STRICT_LIST_TYPE then
 313                                         return false, option:error(ERR.OPT_NOTLIST(option))
 314                                 end
 315                         end
 316
 317                         if option:scheme('datatype') then
 318                                 local dt = option:scheme('datatype')
 319
 320                                 if self.datatypes[dt] then
 321                                         val = ( type(val) == "table" and val or { val } )
 322                                         for i, v in ipairs(val) do
 323                                                 if not self.datatypes[dt]( v ) then
 324                                                         return false, option:error(
 325                                                                 ERR.OPT_INVVALUE(option, { v, dt })
 326                                                         )
 327                                                 end
 328                                         end
 329                                 else
 330                                         return false, option:error(ERR.OPT_DATATYPE(option, dt))
 331                                 end
 332                         end
 333                 end
 334
 335                 if not nodeps then
 336                         local ok, err = luci.uvl.dependencies.check( self, option )
 337                         if not ok then
 338                                 option:error(err)
 339                         end
 340                 end
 341
 342                 local ok, err = luci.uvl.validation.check( self, option )
 343                 if not ok and STRICT_EXTERNAL_VALIDATORS then
 344                         return false, option:error(err)
 345                 end
 346         end
 347
 348         return option:ok(), option:errors()
 349 end
 350
 351 --- Find all parts of given scheme and construct validation tree.
 352 -- This is normally done on demand, so you don't have to call this function
 353 -- by yourself.
 354 -- @param scheme        Name of the scheme to parse
 355 -- @param alias         Create an alias for the loaded scheme
 356 function UVL.read_scheme( self, scheme, alias )
 357
 358         local so = luci.uvl.scheme( self, scheme )
 359         local bc = "%s/bytecode/%s.lua" %{ self.schemedir, scheme }
 360
 361         if not luci.fs.access(bc) then
 362                 local schemes = { }
 363                 local files = luci.fs.glob(self.schemedir .. '/*/' .. scheme)
 364
 365                 if files then
 366                         for i, file in ipairs( files ) do
 367                                 if not luci.fs.access(file) then
 368                                         return false, so:error(ERR.SME_READ(so,file))
 369                                 end
 370
 371                                 local uci = luci.model.uci.cursor( luci.fs.dirname(file), default_savedir )
 372
 373                                 local sd, err = uci:get_all( luci.fs.basename(file) )
 374
 375                                 if not sd then
 376                                         return false, ERR.UCILOAD(so, err)
 377                                 end
 378
 379                                 table.insert( schemes, sd )
 380                         end
 381
 382                         local ok, err = self:_read_scheme_parts( so, schemes )
 383                         if ok and alias then self.packages[alias] = self.packages[scheme] end
 384                         return ok, err
 385                 else
 386                         return false, so:error(ERR.SME_FIND(so, self.schemedir))
 387                 end
 388         else
 389                 local sc = loadfile(bc)
 390                 if sc then
 391                         self.packages[scheme] = sc()
 392                         return true
 393                 else
 394                         return false, so:error(ERR.SME_READ(so,bc))
 395                 end
 396         end
 397 end
 398
 399 -- Process all given parts and construct validation tree
 400 function UVL._read_scheme_parts( self, scheme, schemes )
 401
 402         -- helper function to check for required fields
 403         local function _req( t, n, c, r )
 404                 for i, v in ipairs(r) do
 405                         if not c[v] then
 406                                 local p, o = scheme:sid(), nil
 407
 408                                 if t == TYPE_SECTION then
 409                                         o = section( scheme, nil, p, n )
 410                                 elseif t == TYPE_OPTION then
 411                                         o = option( scheme, nil, p, '(nil)', n )
 412                                 elseif t == TYPE_ENUM then
 413                                         o = enum( scheme, nil, p, '(nil)', '(nil)', n )
 414                                 end
 415
 416                                 return false, ERR.SME_REQFLD(o,v)
 417                         end
 418                 end
 419                 return true
 420         end
 421
 422         -- helper function to validate references
 423         local function _ref( c, t )
 424                 local k, n
 425                 if c == TYPE_SECTION then
 426                         k = "package"
 427                         n = 1
 428                 elseif c == TYPE_OPTION then
 429                         k = "section"
 430                         n = 2
 431                 elseif c == TYPE_ENUM then
 432                         k = "variable"
 433                         n = 3
 434                 end
 435
 436                 local r = luci.util.split( t[k], "." )
 437                 r[1] = ( #r[1] > 0 and r[1] or scheme:sid() )
 438
 439                 if #r ~= n then
 440                         return false, ERR.SME_BADREF(scheme, k)
 441                 end
 442
 443                 return r
 444         end
 445
 446         -- helper function to read bools
 447         local function _bool( v )
 448                 return ( v == "true" or v == "yes" or v == "on" or v == "1" )
 449         end
 450
 451
 452         local ok, err
 453
 454         -- Step 0: get package meta information
 455         for i, conf in ipairs( schemes ) do
 456                 for k, v in pairs( conf ) do
 457                         if v['.type'] == 'package' then
 458                                 self.packages[scheme:sid()] =
 459                                         self.packages[scheme:sid()] or {
 460                                                 ["name"]      = scheme:sid();
 461                                                 ["sections"]  = { };
 462                                                 ["variables"] = { };
 463                                         }
 464
 465                                 for k, v2 in pairs(v) do
 466                                         if k == "title" or k == "description" then
 467                                                 self.packages[scheme:sid()][k] = v2
 468                                         end
 469                                 end
 470                         end
 471                 end
 472         end
 473
 474         -- Step 1: get all sections
 475         for i, conf in ipairs( schemes ) do
 476                 for k, v in pairs( conf ) do
 477                         if v['.type'] == 'section' then
 478
 479                                 ok, err = _req( TYPE_SECTION, k, v, { "name", "package" } )
 480                                 if err then return false, scheme:error(err) end
 481
 482                                 local r, err = _ref( TYPE_SECTION, v )
 483                                 if err then return false, scheme:error(err) end
 484
 485                                 self.packages[r[1]] =
 486                                         self.packages[r[1]] or {
 487                                                 ["name"]      = r[1];
 488                                                 ["sections"]  = { };
 489                                                 ["variables"] = { };
 490                                         }
 491
 492                                 local p = self.packages[r[1]]
 493                                           p.sections[v.name]  = p.sections[v.name]  or { }
 494                                           p.variables[v.name] = p.variables[v.name] or { }
 495
 496                                 local s  = p.sections[v.name]
 497                                 local so = scheme:section(v.name)
 498
 499                                 for k, v2 in pairs(v) do
 500                                         if k ~= "name" and k ~= "package" and k:sub(1,1) ~= "." then
 501                                                 if k == "depends" then
 502                                                         s.depends = self:_read_dependency( v2, s.depends )
 503                                                         if not s.depends then
 504                                                                 return false, scheme:error(
 505                                                                         ERR.SME_BADDEP(so, luci.util.serialize_data(s.depends))
 506                                                                 )
 507                                                         end
 508                                                 elseif k == "dynamic" or k == "unique" or
 509                                                        k == "required" or k == "named"
 510                                                 then
 511                                                         s[k] = _bool(v2)
 512                                                 else
 513                                                         s[k] = v2
 514                                                 end
 515                                         end
 516                                 end
 517
 518                                 s.dynamic  = s.dynamic  or false
 519                                 s.unique   = s.unique   or false
 520                                 s.required = s.required or false
 521                                 s.named    = s.named    or false
 522                         end
 523                 end
 524         end
 525
 526         -- Step 2: get all variables
 527         for i, conf in ipairs( schemes ) do
 528                 for k, v in pairs( conf ) do
 529                         if v['.type'] == "variable" then
 530
 531                                 ok, err = _req( TYPE_OPTION, k, v, { "name", "section" } )
 532                                 if err then return false, scheme:error(err) end
 533
 534                                 local r, err = _ref( TYPE_OPTION, v )
 535                                 if err then return false, scheme:error(err) end
 536
 537                                 local p = self.packages[r[1]]
 538                                 if not p then
 539                                         return false, scheme:error(
 540                                                 ERR.SME_VBADPACK({scheme:sid(), '', v.name}, r[1])
 541                                         )
 542                                 end
 543
 544                                 local s = p.variables[r[2]]
 545                                 if not s then
 546                                         return false, scheme:error(
 547                                                 ERR.SME_VBADSECT({scheme:sid(), '', v.name}, r[2])
 548                                         )
 549                                 end
 550
 551                                 s[v.name] = s[v.name] or { }
 552
 553                                 local t  = s[v.name]
 554                                 local so = scheme:section(r[2])
 555                                 local to = so:option(v.name)
 556
 557                                 for k, v2 in pairs(v) do
 558                                         if k ~= "name" and k ~= "section" and k:sub(1,1) ~= "." then
 559                                                 if k == "depends" then
 560                                                         t.depends = self:_read_dependency( v2, t.depends )
 561                                                         if not t.depends then
 562                                                                 return false, scheme:error(so:error(
 563                                                                         ERR.SME_BADDEP(to, luci.util.serialize_data(v2))
 564                                                                 ))
 565                                                         end
 566                                                 elseif k == "validator" then
 567                                                         t.validators = self:_read_validator( v2, t.validators )
 568                                                         if not t.validators then
 569                                                                 return false, scheme:error(so:error(
 570                                                                         ERR.SME_BADVAL(to, luci.util.serialize_data(v2))
 571                                                                 ))
 572                                                         end
 573                                                 elseif k == "valueof" then
 574                                                         local values, err = self:_read_reference( v2 )
 575                                                         if err then
 576                                                                 return false, scheme:error(so:error(
 577                                                                         ERR.REFERENCE(to, luci.util.serialize_data(v2)):child(err)
 578                                                                 ))
 579                                                         end
 580                                                         t.type   = "reference"
 581                                                         t.values = values
 582                                                 elseif k == "required" then
 583                                                         t[k] = _bool(v2)
 584                                                 else
 585                                                         t[k] = t[k] or v2
 586                                                 end
 587                                         end
 588                                 end
 589
 590                                 t.type     = t.type     or "variable"
 591                                 t.datatype = t.datatype or "string"
 592                                 t.required = t.required or false
 593                         end
 594                 end
 595         end
 596
 597         -- Step 3: get all enums
 598         for i, conf in ipairs( schemes ) do
 599                 for k, v in pairs( conf ) do
 600                         if v['.type'] == "enum" then
 601
 602                                 ok, err = _req( TYPE_ENUM, k, v, { "value", "variable" } )
 603                                 if err then return false, scheme:error(err) end
 604
 605                                 local r, err = _ref( TYPE_ENUM, v )
 606                                 if err then return false, scheme:error(err) end
 607
 608                                 local p = self.packages[r[1]]
 609                                 if not p then
 610                                         return false, scheme:error(
 611                                                 ERR.SME_EBADPACK({scheme:sid(), '', '', v.value}, r[1])
 612                                         )
 613                                 end
 614
 615                                 local s = p.variables[r[2]]
 616                                 if not s then
 617                                         return false, scheme:error(
 618                                                 ERR.SME_EBADSECT({scheme:sid(), '', '', v.value}, r[2])
 619                                         )
 620                                 end
 621
 622                                 local t = s[r[3]]
 623                                 if not t then
 624                                         return false, scheme:error(
 625                                                 ERR.SME_EBADOPT({scheme:sid(), '', '', v.value}, r[3])
 626                                         )
 627                                 end
 628
 629
 630                                 local so = scheme:section(r[2])
 631                                 local oo = so:option(r[3])
 632                                 local eo = oo:enum(v.value)
 633
 634                                 if t.type ~= "enum" and t.type ~= "reference" then
 635                                         return false, scheme:error(ERR.SME_EBADTYPE(eo))
 636                                 end
 637
 638                                 if not t.values then
 639                                         t.values = { [v.value] = v.title or v.value }
 640                                 else
 641                                         t.values[v.value] = v.title or v.value
 642                                 end
 643
 644                                 if not t.enum_depends then
 645                                         t.enum_depends = { }
 646                                 end
 647
 648                                 if v.default then
 649                                         if t.default then
 650                                                 return false, scheme:error(ERR.SME_EBADDEF(eo))
 651                                         end
 652                                         t.default = v.value
 653                                 end
 654
 655                                 if v.depends then
 656                                         t.enum_depends[v.value] = self:_read_dependency(
 657                                                 v.depends, t.enum_depends[v.value]
 658                                         )
 659
 660                                         if not t.enum_depends[v.value] then
 661                                                 return false, scheme:error(so:error(oo:error(
 662                                                         ERR.SME_BADDEP(eo, luci.util.serialize_data(v.depends))
 663                                                 )))
 664                                         end
 665                                 end
 666                         end
 667                 end
 668         end
 669
 670         return self
 671 end
 672
 673 -- Read a dependency specification
 674 function UVL._read_dependency( self, values, deps )
 675         local expr = "%$?[a-zA-Z0-9_]+"
 676         if values then
 677                 values = ( type(values) == "table" and values or { values } )
 678                 for _, value in ipairs(values) do
 679                         local parts     = luci.util.split( value, "%s*,%s*", nil, true )
 680                         local condition = { }
 681                         for i, val in ipairs(parts) do
 682                                 local k, v = unpack(luci.util.split(val, "%s*=%s*", nil, true))
 683
 684                                 if k and (
 685                                         k:match("^"..expr.."%."..expr.."%."..expr.."$") or
 686                                         k:match("^"..expr.."%."..expr.."$") or
 687                                         k:match("^"..expr.."$")
 688                                 ) then
 689                                         condition[k] = v or true
 690                                 else
 691                                         return nil
 692                                 end
 693                         end
 694
 695                         if not deps then
 696                                 deps = { condition }
 697                         else
 698                                 table.insert( deps, condition )
 699                         end
 700                 end
 701         end
 702
 703         return deps
 704 end
 705
 706 -- Read a validator specification
 707 function UVL._read_validator( self, values, validators )
 708         if values then
 709                 values = ( type(values) == "table" and values or { values } )
 710                 for _, value in ipairs(values) do
 711                         local validator
 712
 713                         if value:match("^exec:") then
 714                                 validator = value:gsub("^exec:","")
 715                         elseif value:match("^lua:") then
 716                                 validator = self:_resolve_function( (value:gsub("^lua:","") ) )
 717                         elseif value:match("^regexp:") then
 718                                 local pattern = value:gsub("^regexp:","")
 719                                 validator = function( type, dtype, pack, sect, optn, ... )
 720                                         local values = { ... }
 721                                         for _, v in ipairs(values) do
 722                                                 local ok, match =
 723                                                         luci.util.copcall( string.match, v, pattern )
 724
 725                                                 if not ok then
 726                                                         return false, match
 727                                                 elseif not match then
 728                                                         return false,
 729                                                                 'Value "%s" does not match pattern "%s"' % {
 730                                                                         v, pattern
 731                                                                 }
 732                                                 end
 733                                         end
 734                                         return true
 735                                 end
 736                         end
 737
 738                         if validator then
 739                                 if not validators then
 740                                         validators = { validator }
 741                                 else
 742                                         table.insert( validators, validator )
 743                                 end
 744                         else
 745                                 return nil
 746                         end
 747                 end
 748
 749                 return validators
 750         end
 751 end
 752
 753 -- Read a reference specification (XXX: We should validate external configs too...)
 754 function UVL._read_reference( self, values )
 755         local val = { }
 756         values = ( type(values) == "table" and values or { values } )
 757
 758         for _, value in ipairs(values) do
 759                 local ref = luci.util.split(value, ".")
 760
 761                 if #ref == 2 or #ref == 3 then
 762                         local co = luci.uvl.config( self, ref[1] )
 763                         if not co:config() then return false, co:errors() end
 764
 765                         for k, v in pairs(co:config()) do
 766                                 if v['.type'] == ref[2] then
 767                                         if #ref == 2 then
 768                                                 if v['.anonymous'] == true then
 769                                                         return false, ERR.SME_INVREF('', value)
 770                                                 end
 771                                                 val[k] = k      -- XXX: title/description would be nice
 772                                         elseif v[ref[3]] then
 773                                                 val[v[ref[3]]] = v[ref[3]]  -- XXX: dito
 774                                         end
 775                                 end
 776                         end
 777                 else
 778                         return false, ERR.SME_BADREF('', value)
 779                 end
 780         end
 781
 782         return val, nil
 783 end
 784
 785 -- Resolve given path
 786 function UVL._resolve_function( self, value )
 787         local path = luci.util.split(value, ".")
 788
 789         for i=1, #path-1 do
 790                 local stat, mod = luci.util.copcall(
 791                         require, table.concat(path, ".", 1, i)
 792                 )
 793
 794                 if stat and mod then
 795                         for j=i+1, #path-1 do
 796                                 if not type(mod) == "table" then
 797                                         break
 798                                 end
 799                                 mod = mod[path[j]]
 800                                 if not mod then
 801                                         break
 802                                 end
 803                         end
 804                         mod = type(mod) == "table" and mod[path[#path]] or nil
 805                         if type(mod) == "function" then
 806                                 return mod
 807                         end
 808                 end
 809         end
 810 end
 811
 812
 813 --- Object representation of an uvl item - base class.
 814 uvlitem = luci.util.class()
 815
 816 function uvlitem.cid(self)
 817         if #self.cref == 1 then
 818                 return self.cref[1]
 819         else
 820                 local r = { unpack(self.cref) }
 821                 local c = self.c
 822                 if c and c[r[2]] and c[r[2]]['.anonymous'] and c[r[2]]['.index'] then
 823                         r[2] = '@' .. c[r[2]]['.type'] ..
 824                                '[' .. tostring(c[r[2]]['.index']) .. ']'
 825                 end
 826                 return table.concat( r, '.' )
 827         end
 828 end
 829
 830 function uvlitem.sid(self)
 831         return table.concat( self.sref, '.' )
 832 end
 833
 834 function uvlitem.scheme(self, opt)
 835         local s = self._scheme
 836
 837         if not s then
 838                 s = self.s and self.s.packages and s[self.sref[1]]
 839                 if #self.sref > 1 then
 840                         s = s and s.sections and s[self.sref[2]]
 841                 end
 842                 if #self.sref > 2 then
 843                         s = s and s[self.sref[2]] and s[self.sref[3]]
 844                 end
 845                 self._scheme = s
 846         end
 847
 848         return opt and (s and s[opt]) or s
 849 end
 850
 851 function uvlitem.config(self, opt)
 852         local c = self._config
 853
 854         if not c then
 855                 c = self.c
 856                 if #self.cref > 1 then
 857                         c = c and self.c[self.cref[2]]
 858                 end
 859                 if #self.cref > 2 then
 860                         c = c and c[self.cref[3]]
 861                 end
 862                 self._config = c
 863         end
 864
 865         return opt and (c and c[opt]) or c
 866 end
 867
 868 function uvlitem.title(self)
 869         return self:scheme() and self:scheme('title') or
 870                 self.cref[3] or self.cref[2] or self.cref[1]
 871 end
 872
 873 function uvlitem.type(self)
 874         local _t = {
 875                 [TYPE_CONFIG] = 'config',
 876                 [TYPE_SECTION] = 'section',
 877                 [TYPE_OPTION] = 'option',
 878                 [TYPE_ENUM] = 'enum'
 879         }
 880
 881         return _t[self.t]
 882 end
 883
 884 function uvlitem.error(self, ...)
 885         if not self.e then
 886                 local errconst = { ERR.CONFIG, ERR.SECTION, ERR.OPTION, ERR.OPTION }
 887                 self.e = errconst[#self.cref]( self )
 888         end
 889
 890         return self.e:child( ... )
 891 end
 892
 893 function uvlitem.errors(self)
 894         return self.e
 895 end
 896
 897 function uvlitem.ok(self)
 898         return not self:errors()
 899 end
 900
 901 function uvlitem.parent(self)
 902         if self.p then
 903                 return self.p
 904         elseif #self.cref == 3 or #self.cref == 4 then
 905                 return section( self.s, self.c, self.cref[1], self.cref[2] )
 906         elseif #self.cref == 2 then
 907                 return config( self.s, self.c, self.cref[1] )
 908         else
 909                 return nil
 910         end
 911 end
 912
 913 -- Shared cache
 914 uvlitem._ucicache = {}
 915
 916 function uvlitem._loadconf(self, co, c)
 917         co = co or self._ucicache[c]
 918         if not co then
 919                 local co, err = cursor:get_all(c)
 920
 921                 if err then
 922                         self:error(ERR.UCILOAD(self, err))
 923                 end
 924
 925                 self._ucicache[c] = co
 926         end
 927         return co
 928 end
 929
 930
 931 --- Object representation of a scheme.
 932 -- @class       scheme
 933 -- @cstyle      instance
 934 -- @name        luci.uvl.scheme
 935
 936 --- Scheme instance constructor.
 937 -- @class                       function
 938 -- @name                        scheme
 939 -- @param scheme        Scheme instance
 940 -- @param co            Configuration data
 941 -- @param c                     Configuration name
 942 -- @return                      Config instance
 943 scheme = luci.util.class(uvlitem)
 944
 945 function scheme.__init__(self, scheme, co, c)
 946         if not c then
 947                 c, co = co, nil
 948         end
 949
 950         self.cref = { c }
 951         self.sref = { c }
 952         self.c    = self:_loadconf(co, c)
 953         self.s    = scheme
 954         self.t    = TYPE_SCHEME
 955 end
 956
 957 --- Add an error to scheme.
 958 -- @return      Scheme error context
 959 function scheme.error(self, ...)
 960         if not self.e then self.e = ERR.SCHEME( self ) end
 961         return self.e:child( ... )
 962 end
 963
 964 --- Get an associated config object.
 965 -- @return      Config instance
 966 function scheme.config(self)
 967         local co = config( self.s, self.cref[1] )
 968               co.p = self
 969
 970         return co
 971 end
 972
 973 --- Get all section objects associated with this scheme.
 974 -- @return      Table containing all associated luci.uvl.section instances
 975 function scheme.sections(self)
 976         local v = { }
 977         if self.s.packages[self.sref[1]].sections then
 978                 for o, _ in pairs( self.s.packages[self.sref[1]].sections ) do
 979                         table.insert( v, option(
 980                                 self.s, self.c, self.cref[1], self.cref[2], o
 981                         ) )
 982                 end
 983         end
 984         return v
 985 end
 986
 987 --- Get an associated section object.
 988 -- @param s     Section to select
 989 -- @return      Section instance
 990 function scheme.section(self, s)
 991         local so = section( self.s, self.c, self.cref[1], s )
 992               so.p = self
 993
 994         return so
 995 end
 996
 997
 998 --- Object representation of a config.
 999 -- @class       config
1000 -- @cstyle      instance
1001 -- @name        luci.uvl.config
1002
1003 --- Config instance constructor.
1004 -- @class                       function
1005 -- @name                        config
1006 -- @param scheme        Scheme instance
1007 -- @param co            Configuration data
1008 -- @param c                     Configuration name
1009 -- @return                      Config instance
1010 config = luci.util.class(uvlitem)
1011
1012 function config.__init__(self, scheme, co, c)
1013         if not c then
1014                 c, co = co, nil
1015         end
1016
1017         self.cref = { c }
1018         self.sref = { c }
1019         self.c    = self:_loadconf(co, c)
1020         self.s    = scheme
1021         self.t    = TYPE_CONFIG
1022 end
1023
1024 --- Get all section objects associated with this config.
1025 -- @return      Table containing all associated luci.uvl.section instances
1026 function config.sections(self)
1027         local v = { }
1028         if self.s.packages[self.sref[1]].sections then
1029                 for o, _ in pairs( self.s.packages[self.sref[1]].sections ) do
1030                         table.insert( v, luci.uvl.option(
1031                                 self.s, self.c, self.cref[1], self.cref[2], o
1032                         ) )
1033                 end
1034         end
1035         return v
1036 end
1037
1038 --- Get an associated section object.
1039 -- @param s     Section to select
1040 -- @return      Section instance
1041 function config.section(self, s)
1042         local so = luci.uvl.section( self.s, self.c, self.cref[1], s )
1043               so.p = self
1044
1045         return so
1046 end
1047
1048
1049 --- Object representation of a scheme/config section.
1050 -- @class       module
1051 -- @cstyle      instance
1052 -- @name        luci.uvl.section
1053
1054 --- Section instance constructor.
1055 -- @class                       function
1056 -- @name                        section
1057 -- @param scheme        Scheme instance
1058 -- @param co            Configuration data
1059 -- @param c                     Configuration name
1060 -- @param s                     Section name
1061 -- @return                      Section instance
1062 section = luci.util.class(uvlitem)
1063
1064 function section.__init__(self, scheme, co, c, s)
1065         self.cref = { c, s }
1066         self.sref = { c, co and co[s] and co[s]['.type'] or s }
1067         self.c    = self:_loadconf(co, c)
1068         self.s    = scheme
1069         self.t    = TYPE_SECTION
1070 end
1071
1072 --- Get all option objects associated with this section.
1073 -- @return      Table containing all associated luci.uvl.option instances
1074 function section.variables(self)
1075         local v = { }
1076         if self.s.packages[self.sref[1]].variables[self.sref[2]] then
1077                 for o, _ in pairs(
1078                         self.s.packages[self.sref[1]].variables[self.sref[2]]
1079                 ) do
1080                         table.insert( v, luci.uvl.option(
1081                                 self.s, self.c, self.cref[1], self.cref[2], o
1082                         ) )
1083                 end
1084         end
1085         return v
1086 end
1087
1088 --- Get an associated option object.
1089 -- @param o     Option to select
1090 -- @return      Option instance
1091 function section.option(self, o)
1092         local oo = luci.uvl.option( self.s, self.c, self.cref[1], self.cref[2], o )
1093               oo.p = self
1094
1095         return oo
1096 end
1097
1098
1099 --- Object representation of a scheme/config option.
1100 -- @class       module
1101 -- @cstyle      instance
1102 -- @name        luci.uvl.option
1103
1104 --- Section instance constructor.
1105 -- @class                       function
1106 -- @name                        option
1107 -- @param scheme        Scheme instance
1108 -- @param co            Configuration data
1109 -- @param c                     Configuration name
1110 -- @param s                     Section name
1111 -- @param o                     Option name
1112 -- @return                      Option instance
1113 option = luci.util.class(uvlitem)
1114
1115 function option.__init__(self, scheme, co, c, s, o)
1116         self.cref = { c, s, o }
1117         self.sref = { c, co and co[s] and co[s]['.type'] or s, o }
1118         self.c    = self:_loadconf(co, c)
1119         self.s    = scheme
1120         self.t    = TYPE_OPTION
1121 end
1122
1123 --- Get the value of this option.
1124 -- @return      The associated configuration value
1125 function option.value(self)
1126         local v = self:config() or self:scheme('default')
1127         if v and self:scheme('multival') then
1128                 v = luci.util.split( v, "%s+", nil, true )
1129         end
1130         return v
1131 end
1132
1133 --- Get the associated section information in scheme.
1134 -- @return      Table containing the scheme properties
1135 function option.section(self)
1136         return self.s.packages[self.sref[1]].sections[self.sref[2]]
1137 end
1138
1139 --- Construct an enum object instance from given or default value.
1140 -- @param v     Value to select
1141 -- @return      Enum instance for selected value
1142 function option.enum(self, val)
1143         return enum(
1144                 self.s, self.c,
1145                 self.cref[1], self.cref[2], self.cref[3],
1146                 val or self:value()
1147         )
1148 end
1149
1150
1151 --- Object representation of a enum value.
1152 -- @class       module
1153 -- @cstyle      instance
1154 -- @name        luci.uvl.enum
1155
1156 --- Section instance constructor.
1157 -- @class                       function
1158 -- @name                        enum
1159 -- @param scheme        Scheme instance
1160 -- @param co            Configuration data
1161 -- @param c                     Configuration name
1162 -- @param s                     Section name
1163 -- @param o                     Enum name
1164 -- @param v                     Enum value
1165 -- @return                      Enum value instance
1166 enum = luci.util.class(option)
1167
1168 function enum.__init__(self, scheme, co, c, s, o, v)
1169         self.cref = { c, s, o, v }
1170         self.sref = { c, co and co[s] and co[s]['.type'] or s, o, v }
1171         self.c    = self:_loadconf(co, c)
1172         self.s    = scheme
1173         self.t    = TYPE_ENUM
1174 end