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