libs/uvl/luasrc/uvl.lua

   1 --[[
   2
   3 UCI Validation Layer - Main Library
   4 (c) 2008 Jo-Philipp Wich <xm@leipzig.freifunk.net>
   5 (c) 2008 Steven Barth <steven@midlink.org>
   6
   7 Licensed under the Apache License, Version 2.0 (the "License");
   8 you may not use this file except in compliance with the License.
   9 You may obtain a copy of the License at
  10
  11                 http://www.apache.org/licenses/LICENSE-2.0
  12
  13 $Id$
  14
  15 ]]--
  16
  17
  18 --- UVL - UCI Validation Layer
  19 -- @class       module
  20 -- @cstyle      instance
  21
  22 local fs = require "luci.fs"
  23 local uci = require "luci.model.uci"
  24 local util = require "luci.util"
  25 local table = require "table"
  26 local string = require "string"
  27
  28 local require, pcall, ipairs, pairs = require, pcall, ipairs, pairs
  29 local type, error, tonumber, tostring = type, error, tonumber, tostring
  30 local unpack, loadfile = unpack, loadfile
  31
  32 module "luci.uvl"
  33
  34 local ERR = require "luci.uvl.errors"
  35 local datatypes = require "luci.uvl.datatypes"
  36 local validation = require "luci.uvl.validation"
  37 local dependencies = require "luci.uvl.dependencies"
  38
  39 local TYPE_SCHEME   = 0x00
  40 local TYPE_CONFIG   = 0x01
  41 local TYPE_SECTION  = 0x02
  42 local TYPE_OPTION   = 0x03
  43 local TYPE_ENUM     = 0x04
  44
  45 --- Boolean; default true;
  46 -- treat sections found in config but not in scheme as error
  47 STRICT_UNKNOWN_SECTIONS    = true
  48
  49 --- Boolean; default true;
  50 -- treat options found in config but not in scheme as error
  51 STRICT_UNKNOWN_OPTIONS     = true
  52
  53 --- Boolean; default true;
  54 -- treat failed external validators as error
  55 STRICT_EXTERNAL_VALIDATORS = true
  56
  57 --- Boolean; default true;
  58 -- treat list values stored as options like errors
  59 STRICT_LIST_TYPE           = true
  60
  61
  62 local default_schemedir = "/lib/uci/schema"
  63 local default_savedir = "/tmp/.uvl"
  64
  65
  66 --- Object constructor
  67 -- @class                       function
  68 -- @name                        UVL
  69 -- @param schemedir     Path to the scheme directory (optional)
  70 -- @return                      Instance object
  71 UVL = util.class()
  72
  73 function UVL.__init__( self, schemedir )
  74         self.schemedir  = schemedir or default_schemedir
  75         self.packages   = { }
  76         self.beenthere  = { }
  77         self.depseen    = { }
  78         self.uci                = uci
  79         self.err                = ERR
  80         self.dep                = dependencies
  81         self.datatypes  = datatypes
  82 end
  83
  84
  85 --- Parse given scheme and return the scheme tree.
  86 -- @param scheme        Name of the scheme to parse
  87 -- @return                      Table containing the parsed scheme or nil on error
  88 -- @return                      String containing the reason for errors (if any)
  89 function UVL.get_scheme( self, scheme )
  90         if not self.packages[scheme] then
  91                 local ok, err = self:read_scheme( scheme )
  92                 if not ok then
  93                         return nil, err
  94                 end
  95         end
  96         return self.packages[scheme], nil
  97 end
  98
  99 --- Validate given configuration, section or option.
 100 -- @param config        Name of the configuration to validate
 101 -- @param section       Name of the section to validate (optional)
 102 -- @param option        Name of the option to validate (optional)
 103 -- @return                      Boolean indicating whether the given config validates
 104 -- @return                      String containing the reason for errors (if any)
 105 function UVL.validate( self, config, section, option )
 106         if config and section and option then
 107                 return self:validate_option( config, section, option )
 108         elseif config and section then
 109                 return self:validate_section( config, section )
 110         elseif config then
 111                 return self:validate_config( config )
 112         end
 113 end
 114
 115 --- Validate given configuration.
 116 -- @param cfg   Name of the configuration to validate
 117 -- @return                      Boolean indicating whether the given config validates
 118 -- @return                      String containing the reason for errors (if any)
 119 function UVL.validate_config( self, cfg, uci )
 120
 121         if not self.packages[cfg] then
 122                 local ok, err = self:read_scheme(cfg)
 123                 if not ok then
 124                         return false, err
 125                 end
 126         end
 127
 128         local co = config( self, uci or cfg, uci and cfg )
 129         local sc = { }
 130
 131         self.beenthere = { }
 132         self.depseen   = { }
 133
 134         if not co:config() then
 135                 return false, co:errors()
 136         end
 137
 138         local function _uci_foreach( type, func )
 139                 for k, v in pairs(co:config()) do
 140                         if v['.type'] == type then
 141                                 sc[type] = sc[type] + 1
 142                                 local ok, err = func( k, v )
 143                                 if not ok then co:error(err) end
 144                         end
 145                 end
 146         end
 147
 148         for k, v in pairs( self.packages[cfg].sections ) do
 149                 sc[k] = 0
 150                 _uci_foreach( k,
 151                         function(s)
 152                                 return self:_validate_section( co:section(s) )
 153                         end
 154                 )
 155         end
 156
 157         if STRICT_UNKNOWN_SECTIONS then
 158                 for k, v in pairs(co:config()) do
 159                         local so = co:section(k)
 160                         if not self.beenthere[so:cid()] then
 161                                 co:error(ERR.SECT_UNKNOWN(so))
 162                         end
 163                 end
 164         end
 165
 166         for _, k in ipairs(util.keys(sc)) do
 167                 local so = co:section(k)
 168                 if so:scheme('required') and sc[k] == 0 then
 169                         co:error(ERR.SECT_REQUIRED(so))
 170                 elseif so:scheme('unique') and sc[k] > 1 then
 171                         co:error(ERR.SECT_UNIQUE(so))
 172                 end
 173         end
 174
 175         return co:ok(), co:errors()
 176 end
 177
 178 --- Validate given config section.
 179 -- @param config        Name of the configuration to validate
 180 -- @param section       Name of the section to validate
 181 -- @return                      Boolean indicating whether the given config validates
 182 -- @return                      String containing the reason for errors (if any)
 183 function UVL.validate_section( self, cfg, section, uci )
 184
 185         if not self.packages[cfg] then
 186                 local ok, err = self:read_scheme( cfg )
 187                 if not ok then
 188                         return false, err
 189                 end
 190         end
 191
 192         local co = config( self, uci or cfg, uci and cfg )
 193         local so = co:section( section )
 194
 195         self.beenthere = { }
 196         self.depseen   = { }
 197
 198         if not co:config() then
 199                 return false, co:errors()
 200         end
 201
 202         if so:config() then
 203                 return self:_validate_section( so )
 204         else
 205                 return false, ERR.SECT_NOTFOUND(so)
 206         end
 207 end
 208
 209 --- Validate given config option.
 210 -- @param config        Name of the configuration to validate
 211 -- @param section       Name of the section to validate
 212 -- @param option        Name of the option to validate
 213 -- @return                      Boolean indicating whether the given config validates
 214 -- @return                      String containing the reason for errors (if any)
 215 function UVL.validate_option( self, cfg, section, option, uci )
 216
 217         if not self.packages[cfg] then
 218                 local ok, err = self:read_scheme( cfg )
 219                 if not ok then
 220                         return false, err
 221                 end
 222         end
 223
 224         local co = config( self, uci or cfg, uci and cfg )
 225         local so = co:section( section )
 226         local oo = so:option( option )
 227
 228         if not co:config() then
 229                 return false, co:errors()
 230         end
 231
 232         if so:config() and oo:config() then
 233                 return self:_validate_option( oo )
 234         else
 235                 return false, ERR.OPT_NOTFOUND(oo)
 236         end
 237 end
 238
 239
 240 function UVL._validate_section( self, section )
 241
 242         self.beenthere[section:cid()] = true
 243
 244         if section:config() then
 245                 if section:scheme('named') == true and
 246                    section:config('.anonymous') == true
 247                 then
 248                         return false, ERR.SECT_NAMED(section)
 249                 end
 250
 251                 for _, v in ipairs(section:variables()) do
 252                         local ok, err = self:_validate_option( v )
 253                         if not ok and (
 254                                 v:scheme('required') or v:scheme('type') == "enum" or (
 255                                         not err:is(ERR.ERR_DEP_NOTEQUAL) and
 256                                         not err:is(ERR.ERR_DEP_NOVALUE)
 257                                 )
 258                         ) then
 259                                 section:error(err)
 260                         end
 261                 end
 262
 263                 local ok, err = dependencies.check( self, section )
 264                 if not ok then
 265                         section:error(err)
 266                 end
 267         else
 268                 return false, ERR.SECT_NOTFOUND(section)
 269         end
 270
 271         if STRICT_UNKNOWN_OPTIONS and not section:scheme('dynamic') then
 272                 for k, v in pairs(section:config()) do
 273                         local oo = section:option(k)
 274                         if k:sub(1,1) ~= "." and not self.beenthere[oo:cid()] then
 275                                 section:error(ERR.OPT_UNKNOWN(oo))
 276                         end
 277                 end
 278         end
 279
 280         return section:ok(), section:errors()
 281 end
 282
 283 function UVL._validate_option( self, option, nodeps )
 284
 285         self.beenthere[option:cid()] = true
 286
 287         if not option:scheme() and not option:parent():scheme('dynamic') then
 288                 if STRICT_UNKNOWN_OPTIONS then
 289                         return false, option:error(ERR.OPT_UNKNOWN(option))
 290                 else
 291                         return true
 292                 end
 293
 294         elseif option:scheme() then
 295                 if not nodeps then
 296                         local ok, err = dependencies.check( self, option )
 297                         if not ok then
 298                                 if not err:is_all(
 299                                         ERR.ERR_OPT_REQUIRED,
 300                                         ERR.ERR_DEP_NOTEQUAL,
 301                                         ERR.ERR_DEP_NOVALUE
 302                                 ) then
 303                                         option:error(err)
 304                                         return false, option:errors()
 305                                 else
 306                                         return true
 307                                 end
 308                         end
 309                 end
 310
 311                 if option:scheme('required') and not option:value() then
 312                         return false, option:error(ERR.OPT_REQUIRED(option))
 313
 314                 elseif option:value() then
 315                         local val = option:value()
 316
 317                         if option:scheme('type') == "reference" or
 318                            option:scheme('type') == "enum"
 319                         then
 320                                 local scheme_values = option:scheme('values') or { }
 321                                 local config_values = ( type(val) == "table" and val or { val } )
 322                                 for _, v in ipairs(config_values) do
 323                                         if not scheme_values[v] then
 324                                                 return false, option:error( ERR.OPT_BADVALUE(
 325                                                         option, { v, util.serialize_data(
 326                                                                 util.keys(scheme_values)
 327                                                         ) }
 328                                                 ) )
 329                                         end
 330                                 end
 331                         elseif option:scheme('type') == "list" then
 332                                 if type(val) ~= "table" and STRICT_LIST_TYPE then
 333                                         return false, option:error(ERR.OPT_NOTLIST(option))
 334                                 end
 335                         end
 336
 337                         if option:scheme('datatype') then
 338                                 local dt = option:scheme('datatype')
 339
 340                                 if self.datatypes[dt] then
 341                                         val = ( type(val) == "table" and val or { val } )
 342                                         for i, v in ipairs(val) do
 343                                                 if not self.datatypes[dt]( v ) then
 344                                                         return false, option:error(
 345                                                                 ERR.OPT_INVVALUE(option, { v, dt })
 346                                                         )
 347                                                 end
 348                                         end
 349                                 else
 350                                         return false, option:error(ERR.OPT_DATATYPE(option, dt))
 351                                 end
 352                         end
 353
 354                         val = ( type(val) == "table" and val or { val } )
 355                         for _, v in ipairs(val) do
 356                                 if option:scheme('minlength') then
 357                                         if #v < option:scheme('minlength') then
 358                                                 return false, option:error(ERR.OPT_RANGE(option))
 359                                         end
 360                                 end
 361
 362                                 if option:scheme('maxlength') then
 363                                         if #v > option:scheme('maxlength') then
 364                                                 return false, option:error(ERR.OPT_RANGE(option))
 365                                         end
 366                                 end
 367
 368                                 local w = tonumber(v)
 369
 370                                 if option:scheme('minimum') then
 371                                         if not w or w < option:scheme('minimum') then
 372                                                 return false, option:error(ERR.OPT_RANGE(option))
 373                                         end
 374                                 end
 375
 376                                 if option:scheme('maximum') then
 377                                         if not w or w > option:scheme('maximum') then
 378                                                 return false, option:error(ERR.OPT_RANGE(option))
 379                                         end
 380                                 end
 381
 382                                 if option:scheme('max_nil') then
 383                                         if v and (not w or w > tonumber(option:scheme('max_nil'))) then
 384                                                 return false, option:error(ERR.OPT_RANGE(option))
 385                                         end
 386                                 end
 387                         end
 388                 end
 389
 390                 local ok, err = validation.check( self, option )
 391                 if not ok and STRICT_EXTERNAL_VALIDATORS then
 392                         return false, option:error(err)
 393                 end
 394         end
 395
 396         return option:ok(), option:errors()
 397 end
 398
 399 --- Find all parts of given scheme and construct validation tree.
 400 -- This is normally done on demand, so you don't have to call this function
 401 -- by yourself.
 402 -- @param shm   Name of the scheme to parse
 403 -- @param alias         Create an alias for the loaded scheme
 404 function UVL.read_scheme( self, shm, alias )
 405
 406         local so = scheme( self, shm )
 407         local bc = "%s/bytecode/%s.lua" %{ self.schemedir, shm }
 408
 409         if not fs.access(bc) then
 410                 local files = fs.glob(self.schemedir .. '/*/' .. shm)
 411
 412                 if files then
 413                         local ok, err
 414                         for i, file in ipairs( files ) do
 415                                 if not fs.access(file) then
 416                                         return false, so:error(ERR.SME_READ(so,file))
 417                                 end
 418
 419                                 local uci = uci.cursor( fs.dirname(file), default_savedir )
 420
 421                                 local sname = fs.basename(file)
 422                                 local sd, err = uci:load( sname )
 423
 424                                 if not sd then
 425                                         return false, ERR.UCILOAD(so, err)
 426                                 end
 427
 428                                 ok, err = pcall(function()
 429                                         uci:foreach(sname, "package", function(s)
 430                                                 self:_parse_package(so, s[".name"], s)
 431                                         end)
 432                                         uci:foreach(sname, "section", function(s)
 433                                                 self:_parse_section(so, s[".name"], s)
 434                                         end)
 435                                         uci:foreach(sname, "variable", function(s)
 436                                                 self:_parse_var(so, s[".name"], s)
 437                                         end)
 438                                         uci:foreach(sname, "enum", function(s)
 439                                                 self:_parse_enum(so, s[".name"], s)
 440                                         end)
 441
 442                                 end)
 443                         end
 444
 445                         if ok and alias then self.packages[alias] = self.packages[shm] end
 446                         return ok and self, err
 447                 else
 448                         return false, so:error(ERR.SME_FIND(so, self.schemedir))
 449                 end
 450         else
 451                 local sc = loadfile(bc)
 452                 if sc then
 453                         self.packages[shm] = sc()
 454                         return true
 455                 else
 456                         return false, so:error(ERR.SME_READ(so,bc))
 457                 end
 458         end
 459 end
 460
 461 -- helper function to check for required fields
 462 local function _req( t, n, c, r )
 463         for i, v in ipairs(r) do
 464                 if not c[v] then
 465                         local p, o = scheme:sid(), nil
 466
 467                         if t == TYPE_SECTION then
 468                                 o = section( scheme, nil, p, n )
 469                         elseif t == TYPE_OPTION then
 470                                 o = option( scheme, nil, p, '(nil)', n )
 471                         elseif t == TYPE_ENUM then
 472                                 o = enum( scheme, nil, p, '(nil)', '(nil)', n )
 473                         end
 474
 475                         return false, ERR.SME_REQFLD(o,v)
 476                 end
 477         end
 478         return true
 479 end
 480
 481 -- helper function to validate references
 482 local function _ref( c, t )
 483         local r, k, n = {}
 484         if c == TYPE_SECTION then
 485                 k = "package"
 486                 n = 1
 487         elseif c == TYPE_OPTION then
 488                 k = "section"
 489                 n = 2
 490         elseif c == TYPE_ENUM then
 491                 k = "variable"
 492                 n = 3
 493         end
 494
 495         for o in t[k]:gmatch("[^.]+") do
 496                 r[#r+1] = o
 497         end
 498         r[1] = ( #r[1] > 0 and r[1] or scheme:sid() )
 499
 500         if #r ~= n then
 501                 return false, ERR.SME_BADREF(scheme, k)
 502         end
 503
 504         return r
 505 end
 506
 507 -- helper function to read bools
 508 local function _bool( v )
 509         return ( v == "true" or v == "yes" or v == "on" or v == "1" )
 510 end
 511
 512 -- Step 0: get package meta information
 513 function UVL._parse_package(self, scheme, k, v)
 514         local sid = scheme:sid()
 515         local pkg = self.packages[sid] or {
 516                 ["name"]      = sid;
 517                 ["sections"]  = { };
 518                 ["variables"] = { };
 519         }
 520
 521         pkg.title = v.title
 522         pkg.description = v.description
 523
 524         self.packages[sid] = pkg
 525 end
 526
 527 -- Step 1: get all sections
 528 function UVL._parse_section(self, scheme, k, v)
 529         local ok, err = _req( TYPE_SECTION, k, v, { "name", "package" } )
 530         if err then error(scheme:error(err)) end
 531
 532         local r, err = _ref( TYPE_SECTION, v )
 533         if err then error(scheme:error(err)) end
 534
 535         local p = self.packages[r[1]] or {
 536                 ["name"]      = r[1];
 537                 ["sections"]  = { };
 538                 ["variables"] = { };
 539         }
 540         p.sections[v.name]  = p.sections[v.name]  or { }
 541         p.variables[v.name] = p.variables[v.name] or { }
 542         self.packages[r[1]] = p
 543
 544         local s  = p.sections[v.name]
 545         local so = scheme:section(v.name)
 546
 547         for k, v2 in pairs(v) do
 548                 if k ~= "name" and k ~= "package" and k:sub(1,1) ~= "." then
 549                         if k == "depends" then
 550                                 s.depends = self:_read_dependency( v2, s.depends )
 551                                 if not s.depends then
 552                                         return false, scheme:error(
 553                                                 ERR.SME_BADDEP(so, util.serialize_data(s.depends))
 554                                         )
 555                                 end
 556                         elseif k == "dynamic" or k == "unique" or
 557                                k == "required" or k == "named"
 558                         then
 559                                 s[k] = _bool(v2)
 560                         else
 561                                 s[k] = v2
 562                         end
 563                 end
 564         end
 565
 566         s.dynamic  = s.dynamic  or false
 567         s.unique   = s.unique   or false
 568         s.required = s.required or false
 569         s.named    = s.named    or false
 570 end
 571
 572 -- Step 2: get all variables
 573 function UVL._parse_var(self, scheme, k, v)
 574         local ok, err = _req( TYPE_OPTION, k, v, { "name", "section" } )
 575         if err then error(scheme:error(err)) end
 576
 577         local r, err = _ref( TYPE_OPTION, v )
 578         if err then error(scheme:error(err)) end
 579
 580         local p = self.packages[r[1]]
 581         if not p then
 582                 error(scheme:error(
 583                         ERR.SME_VBADPACK({scheme:sid(), '', v.name}, r[1])
 584                 ))
 585         end
 586
 587         local s = p.variables[r[2]]
 588         if not s then
 589                 error(scheme:error(
 590                         ERR.SME_VBADSECT({scheme:sid(), '', v.name}, r[2])
 591                 ))
 592         end
 593
 594         s[v.name] = s[v.name] or { }
 595
 596         local t  = s[v.name]
 597         local so = scheme:section(r[2])
 598         local to = so:option(v.name)
 599
 600         for k, v2 in pairs(v) do
 601                 if k ~= "name" and k ~= "section" and k:sub(1,1) ~= "." then
 602                         if k == "depends" then
 603                                 t.depends = self:_read_dependency( v2, t.depends )
 604                                 if not t.depends then
 605                                         error(scheme:error(so:error(
 606                                                 ERR.SME_BADDEP(to, util.serialize_data(v2))
 607                                         )))
 608                                 end
 609                         elseif k == "validator" then
 610                                 t.validators = self:_read_validator( v2, t.validators )
 611                                 if not t.validators then
 612                                         error(scheme:error(so:error(
 613                                                 ERR.SME_BADVAL(to, util.serialize_data(v2))
 614                                         )))
 615                                 end
 616                         elseif k == "valueof" then
 617                                 local values, err = self:_read_reference( v2 )
 618                                 if err then
 619                                         error(scheme:error(so:error(
 620                                                 ERR.REFERENCE(to, util.serialize_data(v2)):child(err)
 621                                         )))
 622                                 end
 623                                 t.type   = "reference"
 624                                 t.values = values
 625                                 t.valueof = type(v2) == "table" and v2 or {v2}
 626                         elseif k == "required" then
 627                                 t[k] = _bool(v2)
 628                         elseif k == "minlength" or k == "maxlength" or
 629                    k == "minimum" or k == "maximum"
 630             then
 631                                 t[k] = tonumber(v2)
 632                         else
 633                                 t[k] = t[k] or v2
 634                         end
 635                 end
 636         end
 637
 638         t.type     = t.type     or "variable"
 639         t.datatype = t.datatype or "string"
 640         t.required = t.required or false
 641 end
 642
 643 -- Step 3: get all enums
 644 function UVL._parse_enum(self, scheme, k, v)
 645         local ok, err = _req( TYPE_ENUM, k, v, { "value", "variable" } )
 646         if err then error(scheme:error(err)) end
 647
 648         local r, err = _ref( TYPE_ENUM, v )
 649         if err then error(scheme:error(err)) end
 650
 651         local p = self.packages[r[1]]
 652         if not p then
 653                 error(scheme:error(
 654                         ERR.SME_EBADPACK({scheme:sid(), '', '', v.value}, r[1])
 655                 ))
 656         end
 657
 658         local s = p.variables[r[2]]
 659         if not s then
 660                 error(scheme:error(
 661                         ERR.SME_EBADSECT({scheme:sid(), '', '', v.value}, r[2])
 662                 ))
 663         end
 664
 665         local t = s[r[3]]
 666         if not t then
 667                 error(scheme:error(
 668                         ERR.SME_EBADOPT({scheme:sid(), '', '', v.value}, r[3])
 669                 ))
 670         end
 671
 672
 673         local so = scheme:section(r[2])
 674         local oo = so:option(r[3])
 675         local eo = oo:enum(v.value)
 676
 677         if t.type ~= "enum" and t.type ~= "reference" then
 678                 error(scheme:error(ERR.SME_EBADTYPE(eo)))
 679         end
 680
 681         if not t.values then
 682                 t.values = { [v.value] = v.title or v.value }
 683                 t.valuelist = { {value = v.value, title = v.title} }
 684         else
 685                 t.values[v.value] = v.title or v.value
 686                 t.valuelist[#t.valuelist + 1] = {value = v.value, title = v.title}
 687         end
 688
 689         if not t.enum_depends then
 690                 t.enum_depends = { }
 691         end
 692
 693         if v.default then
 694                 if t.default then
 695                         error(scheme:error(ERR.SME_EBADDEF(eo)))
 696                 end
 697                 t.default = v.value
 698         end
 699
 700         if v.depends then
 701                 t.enum_depends[v.value] = self:_read_dependency(
 702                         v.depends, t.enum_depends[v.value]
 703                 )
 704
 705                 if not t.enum_depends[v.value] then
 706                         error(scheme:error(so:error(oo:error(
 707                                 ERR.SME_BADDEP(eo, util.serialize_data(v.depends))
 708                         ))))
 709                 end
 710         end
 711 end
 712
 713 -- Read a dependency specification
 714 function UVL._read_dependency( self, values, deps )
 715         local expr = "%$?[%w_]+"
 716         if values then
 717                 values = ( type(values) == "table" and values or { values } )
 718                 for _, value in ipairs(values) do
 719                         local condition = { }
 720                         for val in value:gmatch("[^,]+") do
 721                                 local k, e, v = val:match("%s*([%w$_.]+)%s*(=?)%s*(.*)")
 722
 723                                 if k and (
 724                                         k:match("^"..expr.."%."..expr.."%."..expr.."$") or
 725                                         k:match("^"..expr.."%."..expr.."$") or
 726                                         k:match("^"..expr.."$")
 727                                 ) then
 728                                         condition[k] = (e == '=') and v or true
 729                                 else
 730                                         return nil
 731                                 end
 732                         end
 733
 734                         if not deps then
 735                                 deps = { condition }
 736                         else
 737                                 deps[#deps+1] = condition
 738                         end
 739                 end
 740         end
 741
 742         return deps
 743 end
 744
 745 -- Read a validator specification
 746 function UVL._read_validator( self, values, validators )
 747         if values then
 748                 values = ( type(values) == "table" and values or { values } )
 749                 for _, value in ipairs(values) do
 750                         local validator
 751
 752                         if value:match("^exec:") then
 753                                 validator = value:gsub("^exec:","")
 754                         elseif value:match("^lua:") then
 755                                 validator = self:_resolve_function( (value:gsub("^lua:","") ) )
 756                         elseif value:match("^regexp:") then
 757                                 local pattern = value:gsub("^regexp:","")
 758                                 validator = function( type, dtype, pack, sect, optn, ... )
 759                                         local values = { ... }
 760                                         for _, v in ipairs(values) do
 761                                                 local ok, match =
 762                                                         pcall( string.match, v, pattern )
 763
 764                                                 if not ok then
 765                                                         return false, match
 766                                                 elseif not match then
 767                                                         return false,
 768                                                                 'Value "%s" does not match pattern "%s"' % {
 769                                                                         v, pattern
 770                                                                 }
 771                                                 end
 772                                         end
 773                                         return true
 774                                 end
 775                         end
 776
 777                         if validator then
 778                                 if not validators then
 779                                         validators = { validator }
 780                                 else
 781                                         validators[#validators+1] = validator
 782                                 end
 783                         else
 784                                 return nil
 785                         end
 786                 end
 787
 788                 return validators
 789         end
 790 end
 791
 792 -- Read a reference specification (XXX: We should validate external configs too...)
 793 function UVL._read_reference( self, values )
 794         local val = { }
 795         values = ( type(values) == "table" and values or { values } )
 796
 797         for _, value in ipairs(values) do
 798                 local ref = util.split(value, ".")
 799
 800                 if #ref == 2 or #ref == 3 then
 801                         local co = config( self, ref[1] )
 802                         if not co:config() then return false, co:errors() end
 803
 804                         for k, v in pairs(co:config()) do
 805                                 if v['.type'] == ref[2] then
 806                                         if #ref == 2 then
 807                                                 if v['.anonymous'] == true then
 808                                                         return false, ERR.SME_INVREF('', value)
 809                                                 end
 810                                                 val[k] = k      -- XXX: title/description would be nice
 811                                         elseif v[ref[3]] then
 812                                                 val[v[ref[3]]] = v[ref[3]]  -- XXX: dito
 813                                         end
 814                                 end
 815                         end
 816                 else
 817                         return false, ERR.SME_BADREF('', value)
 818                 end
 819         end
 820
 821         return val, nil
 822 end
 823
 824 -- Resolve given path
 825 function UVL._resolve_function( self, value )
 826         local path = util.split(value, ".")
 827
 828         for i=1, #path-1 do
 829                 local stat, mod = pcall(
 830                         require, table.concat(path, ".", 1, i)
 831                 )
 832
 833                 if stat and mod then
 834                         for j=i+1, #path-1 do
 835                                 if not type(mod) == "table" then
 836                                         break
 837                                 end
 838                                 mod = mod[path[j]]
 839                                 if not mod then
 840                                         break
 841                                 end
 842                         end
 843                         mod = type(mod) == "table" and mod[path[#path]] or nil
 844                         if type(mod) == "function" then
 845                                 return mod
 846                         end
 847                 end
 848         end
 849 end
 850
 851
 852 --- Object representation of an uvl item - base class.
 853 uvlitem = util.class()
 854
 855 function uvlitem.cid(self)
 856         if #self.cref == 1 then
 857                 return self.cref[1]
 858         else
 859                 local r = { unpack(self.cref) }
 860                 local c = self.c
 861                 if c and c[r[2]] and c[r[2]]['.anonymous'] and c[r[2]]['.index'] then
 862                         r[2] = '@' .. c[r[2]]['.type'] ..
 863                                    '[' .. tostring(c[r[2]]['.index']) .. ']'
 864                 end
 865                 return table.concat( r, '.' )
 866         end
 867 end
 868
 869 function uvlitem.sid(self)
 870         return table.concat( self.sref, '.' )
 871 end
 872
 873 function uvlitem.scheme(self, opt)
 874         local s = self.s and self.s.packages
 875         s = s      and s[self.sref[1]]
 876         if #self.sref == 4 or #self.sref == 3 then
 877                 s = s      and s.variables
 878                 s = s      and s[self.sref[2]]
 879                 s = s      and s[self.sref[3]]
 880         elseif #self.sref == 2 then
 881                 s = s      and s.sections
 882                 s = s      and s[self.sref[2]]
 883         end
 884
 885         if s and opt then
 886                 return s[opt]
 887         elseif s then
 888                 return s
 889         end
 890 end
 891
 892 function uvlitem.config(self, opt)
 893         local c = self.c
 894
 895         if #self.cref >= 2 and #self.cref <= 4 then
 896                 c = c and self.c[self.cref[2]] or nil
 897                 if #self.cref >= 3 then
 898                         c = c and c[self.cref[3]] or nil
 899                 end
 900         end
 901
 902         if c and opt then
 903                 return c[opt]
 904         elseif c then
 905                 return c
 906         end
 907 end
 908
 909 function uvlitem.title(self)
 910         return self:scheme() and self:scheme('title') or
 911                 self.cref[3] or self.cref[2] or self.cref[1]
 912 end
 913
 914 function uvlitem.type(self)
 915         if self.t == TYPE_CONFIG then
 916                 return 'config'
 917         elseif self.t == TYPE_SECTION then
 918                 return 'section'
 919         elseif self.t == TYPE_OPTION then
 920                 return 'option'
 921         elseif self.t == TYPE_ENUM then
 922                 return 'enum'
 923         end
 924 end
 925
 926 function uvlitem.error(self, ...)
 927         if not self.e then
 928                 local errconst = { ERR.CONFIG, ERR.SECTION, ERR.OPTION, ERR.OPTION }
 929                 self.e = errconst[#self.cref]( self )
 930         end
 931
 932         return self.e:child( ... )
 933 end
 934
 935 function uvlitem.errors(self)
 936         return self.e
 937 end
 938
 939 function uvlitem.ok(self)
 940         return not self:errors()
 941 end
 942
 943 function uvlitem.parent(self)
 944         if self.p then
 945                 return self.p
 946         elseif #self.cref == 3 or #self.cref == 4 then
 947                 return section( self.s, self.c, self.cref[1], self.cref[2] )
 948         elseif #self.cref == 2 then
 949                 return config( self.s, self.c, self.cref[1] )
 950         else
 951                 return nil
 952         end
 953 end
 954
 955 function uvlitem._loadconf(self, co, c)
 956         co = co or self._configcache
 957         if not co then
 958                 local err
 959                 co, err = uci.cursor():get_all(c)
 960
 961                 if err then
 962                         self:error(ERR.UCILOAD(self, err))
 963                 end
 964
 965                 self._configcache = co
 966         end
 967         return co
 968 end
 969
 970
 971 --- Object representation of a scheme.
 972 -- @class       scheme
 973 -- @cstyle      instance
 974 -- @name        luci.uvl.scheme
 975
 976 --- Scheme instance constructor.
 977 -- @class                       function
 978 -- @name                        scheme
 979 -- @param scheme        Scheme instance
 980 -- @param co            Configuration data
 981 -- @param c                     Configuration name
 982 -- @return                      Config instance
 983 scheme = util.class(uvlitem)
 984
 985 function scheme.__init__(self, scheme, co, c)
 986         if not c then
 987                 c, co = co, nil
 988         end
 989
 990         self.cref = { c }
 991         self.sref = { c }
 992         self.c    = self:_loadconf(co, c)
 993         self.s    = scheme
 994         self.t    = TYPE_SCHEME
 995 end
 996
 997 --- Add an error to scheme.
 998 -- @return      Scheme error context
 999 function scheme.error(self, ...)
1000         if not self.e then self.e = ERR.SCHEME( self ) end
1001         return self.e:child( ... )
1002 end
1003
1004 --- Get an associated config object.
1005 -- @return      Config instance
1006 function scheme.config(self)
1007         local co = config( self.s, self.cref[1] )
1008               co.p = self
1009
1010         return co
1011 end
1012
1013 --- Get all section objects associated with this scheme.
1014 -- @return      Table containing all associated luci.uvl.section instances
1015 function scheme.sections(self)
1016         local v = { }
1017         if self.s.packages[self.sref[1]].sections then
1018                 for o, _ in pairs( self.s.packages[self.sref[1]].sections ) do
1019                         v[#v+1] = option(
1020                                 self.s, self.c, self.cref[1], self.cref[2], o
1021                         )
1022                 end
1023         end
1024         return v
1025 end
1026
1027 --- Get an associated section object.
1028 -- @param s     Section to select
1029 -- @return      Section instance
1030 function scheme.section(self, s)
1031         local so = section( self.s, self.c, self.cref[1], s )
1032               so.p = self
1033
1034         return so
1035 end
1036
1037
1038 --- Object representation of a config.
1039 -- @class       config
1040 -- @cstyle      instance
1041 -- @name        luci.uvl.config
1042
1043 --- Config instance constructor.
1044 -- @class                       function
1045 -- @name                        config
1046 -- @param scheme        Scheme instance
1047 -- @param co            Configuration data
1048 -- @param c                     Configuration name
1049 -- @return                      Config instance
1050 config = util.class(uvlitem)
1051
1052 function config.__init__(self, scheme, co, c)
1053         if not c then
1054                 c, co = co, nil
1055         end
1056
1057         self.cref = { c }
1058         self.sref = { c }
1059         self.c    = self:_loadconf(co, c)
1060         self.s    = scheme
1061         self.t    = TYPE_CONFIG
1062 end
1063
1064 --- Get all section objects associated with this config.
1065 -- @return      Table containing all associated luci.uvl.section instances
1066 function config.sections(self)
1067         local v = { }
1068         if self.s.packages[self.sref[1]].sections then
1069                 for o, _ in pairs( self.s.packages[self.sref[1]].sections ) do
1070                         v[#v+1] = option(
1071                                 self.s, self.c, self.cref[1], self.cref[2], o
1072                         )
1073                 end
1074         end
1075         return v
1076 end
1077
1078 --- Get an associated section object.
1079 -- @param s     Section to select
1080 -- @return      Section instance
1081 function config.section(self, s)
1082         local so = section( self.s, self.c, self.cref[1], s )
1083               so.p = self
1084
1085         return so
1086 end
1087
1088
1089 --- Object representation of a scheme/config section.
1090 -- @class       module
1091 -- @cstyle      instance
1092 -- @name        luci.uvl.section
1093
1094 --- Section instance constructor.
1095 -- @class                       function
1096 -- @name                        section
1097 -- @param scheme        Scheme instance
1098 -- @param co            Configuration data
1099 -- @param c                     Configuration name
1100 -- @param s                     Section name
1101 -- @return                      Section instance
1102 section = util.class(uvlitem)
1103
1104 function section.__init__(self, scheme, co, c, s)
1105         self.cref = { c, s }
1106         self.sref = { c, co and co[s] and co[s]['.type'] or s }
1107         self.c    = self:_loadconf(co, c)
1108         self.s    = scheme
1109         self.t    = TYPE_SECTION
1110 end
1111
1112 --- Get all option objects associated with this section.
1113 -- @return      Table containing all associated luci.uvl.option instances
1114 function section.variables(self)
1115         local v = { }
1116         if self.s.packages[self.sref[1]].variables[self.sref[2]] then
1117                 for o, _ in pairs(
1118                         self.s.packages[self.sref[1]].variables[self.sref[2]]
1119                 ) do
1120                         v[#v+1] = option(
1121                                 self.s, self.c, self.cref[1], self.cref[2], o
1122                         )
1123                 end
1124         end
1125         return v
1126 end
1127
1128 --- Get an associated option object.
1129 -- @param o     Option to select
1130 -- @return      Option instance
1131 function section.option(self, o)
1132         local oo = option( self.s, self.c, self.cref[1], self.cref[2], o )
1133               oo.p = self
1134
1135         return oo
1136 end
1137
1138
1139 --- Object representation of a scheme/config option.
1140 -- @class       module
1141 -- @cstyle      instance
1142 -- @name        luci.uvl.option
1143
1144 --- Section instance constructor.
1145 -- @class                       function
1146 -- @name                        option
1147 -- @param scheme        Scheme instance
1148 -- @param co            Configuration data
1149 -- @param c                     Configuration name
1150 -- @param s                     Section name
1151 -- @param o                     Option name
1152 -- @return                      Option instance
1153 option = util.class(uvlitem)
1154
1155 function option.__init__(self, scheme, co, c, s, o)
1156         self.cref = { c, s, o }
1157         self.sref = { c, co and co[s] and co[s]['.type'] or s, o }
1158         self.c    = self:_loadconf(co, c)
1159         self.s    = scheme
1160         self.t    = TYPE_OPTION
1161 end
1162
1163 --- Get the value of this option.
1164 -- @return      The associated configuration value
1165 function option.value(self)
1166         local v = self:config() or self:scheme('default')
1167         if v and self:scheme('multival') then
1168                 v = util.split( v, "%s+", nil, true )
1169         end
1170         return v
1171 end
1172
1173 --- Get the associated section information in scheme.
1174 -- @return      Table containing the scheme properties
1175 function option.section(self)
1176         return self.s.packages[self.sref[1]].sections[self.sref[2]]
1177 end
1178
1179 --- Construct an enum object instance from given or default value.
1180 -- @param v     Value to select
1181 -- @return      Enum instance for selected value
1182 function option.enum(self, val)
1183         return enum(
1184                 self.s, self.c,
1185                 self.cref[1], self.cref[2], self.cref[3],
1186                 val or self:value()
1187         )
1188 end
1189
1190
1191 --- Object representation of a enum value.
1192 -- @class       module
1193 -- @cstyle      instance
1194 -- @name        luci.uvl.enum
1195
1196 --- Section instance constructor.
1197 -- @class                       function
1198 -- @name                        enum
1199 -- @param scheme        Scheme instance
1200 -- @param co            Configuration data
1201 -- @param c                     Configuration name
1202 -- @param s                     Section name
1203 -- @param o                     Enum name
1204 -- @param v                     Enum value
1205 -- @return                      Enum value instance
1206 enum = util.class(option)
1207
1208 function enum.__init__(self, scheme, co, c, s, o, v)
1209         self.cref = { c, s, o, v }
1210         self.sref = { c, co and co[s] and co[s]['.type'] or s, o, v }
1211         self.c    = self:_loadconf(co, c)
1212         self.s    = scheme
1213         self.t    = TYPE_ENUM
1214 end