libs/sys/luasrc/sys.lua

   1 --[[
   2 LuCI - System library
   3
   4 Description:
   5 Utilities for interaction with the Linux system
   6
   7 FileId:
   8 $Id$
   9
  10 License:
  11 Copyright 2008 Steven Barth <steven@midlink.org>
  12
  13 Licensed under the Apache License, Version 2.0 (the "License");
  14 you may not use this file except in compliance with the License.
  15 You may obtain a copy of the License at
  16
  17         http://www.apache.org/licenses/LICENSE-2.0
  18
  19 Unless required by applicable law or agreed to in writing, software
  20 distributed under the License is distributed on an "AS IS" BASIS,
  21 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  22 See the License for the specific language governing permissions and
  23 limitations under the License.
  24
  25 ]]--
  26
  27
  28 local io    = require "io"
  29 local os    = require "os"
  30 local posix = require "posix"
  31 local table = require "table"
  32
  33 local luci  = {}
  34 luci.util   = require "luci.util"
  35 luci.fs     = require "luci.fs"
  36 luci.ip     = require "luci.ip"
  37
  38 local tonumber, ipairs, pairs, pcall = tonumber, ipairs, pairs, pcall
  39
  40
  41 --- LuCI Linux and POSIX system utilities.
  42 module "luci.sys"
  43
  44 --- Execute a given shell command and return the error code
  45 -- @class               function
  46 -- @name                call
  47 -- @param               ...             Command to call
  48 -- @return              Error code of the command
  49 function call(...)
  50         return os.execute(...) / 256
  51 end
  52
  53 --- Execute a given shell command and capture its standard output
  54 -- @class               function
  55 -- @name                exec
  56 -- @param command       Command to call
  57 -- @return                      String containg the return the output of the command
  58 exec = luci.util.exec
  59
  60 --- Invoke the luci-flash executable to write an image to the flash memory.
  61 -- @param image         Local path or URL to image file
  62 -- @param kpattern      Pattern of files to keep over flash process
  63 -- @return                      Return value of os.execute()
  64 function flash(image, kpattern)
  65         local cmd = "luci-flash "
  66         if kpattern then
  67                 cmd = cmd .. "-k '" .. kpattern:gsub("'", "") .. "' "
  68         end
  69         cmd = cmd .. "'" .. image:gsub("'", "") .. "' >/dev/null 2>&1"
  70
  71         return os.execute(cmd)
  72 end
  73
  74 --- Retrieve information about currently mounted file systems.
  75 -- @return      Table containing mount information
  76 function mounts()
  77         local data = {}
  78         local k = {"fs", "blocks", "used", "available", "percent", "mountpoint"}
  79         local ps = luci.util.execi("df")
  80
  81         if not ps then
  82                 return
  83         else
  84                 ps()
  85         end
  86
  87         for line in ps do
  88                 local row = {}
  89
  90                 local j = 1
  91                 for value in line:gmatch("[^%s]+") do
  92                         row[k[j]] = value
  93                         j = j + 1
  94                 end
  95
  96                 if row[k[1]] then
  97
  98                         -- this is a rather ugly workaround to cope with wrapped lines in
  99                         -- the df output:
 100                         --
 101                         --      /dev/scsi/host0/bus0/target0/lun0/part3
 102                         --                   114382024  93566472  15005244  86% /mnt/usb
 103                         --
 104
 105                         if not row[k[2]] then
 106                                 j = 2
 107                                 line = ps()
 108                                 for value in line:gmatch("[^%s]+") do
 109                                         row[k[j]] = value
 110                                         j = j + 1
 111                                 end
 112                         end
 113
 114                         table.insert(data, row)
 115                 end
 116         end
 117
 118         return data
 119 end
 120
 121 --- Retrieve environment variables. If no variable is given then a table
 122 -- containing the whole environment is returned otherwise this function returns
 123 -- the corresponding string value for the given name or nil if no such variable
 124 -- exists.
 125 -- @class               function
 126 -- @name                getenv
 127 -- @param var   Name of the environment variable to retrieve (optional)
 128 -- @return              String containg the value of the specified variable
 129 -- @return              Table containing all variables if no variable name is given
 130 getenv = posix.getenv
 131
 132 --- Determine the current hostname.
 133 -- @return              String containing the system hostname
 134 function hostname()
 135         return posix.uname("%n")
 136 end
 137
 138 --- Returns the contents of a documented referred by an URL.
 139 -- @param url    The URL to retrieve
 140 -- @param stream Return a stream instead of a buffer
 141 -- @param target Directly write to target file name
 142 -- @return              String containing the contents of given the URL
 143 function httpget(url, stream, target)
 144         if not target then
 145                 local source = stream and io.popen or luci.util.exec
 146                 return source("wget -qO- '"..url:gsub("'", "").."'")
 147         else
 148                 return os.execute("wget -qO '%s' '%s'" %
 149                         {target:gsub("'", ""), url:gsub("'", "")})
 150         end
 151 end
 152
 153 --- Returns the system load average values.
 154 -- @return      String containing the average load value 1 minute ago
 155 -- @return      String containing the average load value 5 minutes ago
 156 -- @return      String containing the average load value 15 minutes ago
 157 -- @return      String containing the active and total number of processes
 158 -- @return      String containing the last used pid
 159 function loadavg()
 160         local loadavg = io.lines("/proc/loadavg")()
 161         return loadavg:match("^(.-) (.-) (.-) (.-) (.-)$")
 162 end
 163
 164 --- Initiate a system reboot.
 165 -- @return      Return value of os.execute()
 166 function reboot()
 167         return os.execute("reboot >/dev/null 2>&1")
 168 end
 169
 170 --- Returns the system type, cpu name and installed physical memory.
 171 -- @return      String containing the system or platform identifier
 172 -- @return      String containing hardware model information
 173 -- @return      String containing the total memory amount in kB
 174 -- @return      String containing the memory used for caching in kB
 175 -- @return      String containing the memory used for buffering in kB
 176 -- @return      String containing the free memory amount in kB
 177 function sysinfo()
 178         local cpuinfo = luci.fs.readfile("/proc/cpuinfo")
 179         local meminfo = luci.fs.readfile("/proc/meminfo")
 180
 181         local system = cpuinfo:match("system typ.-:%s*([^\n]+)")
 182         local model = ""
 183         local memtotal = tonumber(meminfo:match("MemTotal:%s*(%d+)"))
 184         local memcached = tonumber(meminfo:match("\nCached:%s*(%d+)"))
 185         local memfree = tonumber(meminfo:match("MemFree:%s*(%d+)"))
 186         local membuffers = tonumber(meminfo:match("Buffers:%s*(%d+)"))
 187
 188         if not system then
 189                 system = posix.uname("%m")
 190                 model = cpuinfo:match("model name.-:%s*([^\n]+)")
 191                 if not model then
 192                         model = cpuinfo:match("Processor.-:%s*([^\n]+)")
 193                 end
 194         else
 195                 model = cpuinfo:match("cpu model.-:%s*([^\n]+)")
 196         end
 197
 198         return system, model, memtotal, memcached, membuffers, memfree
 199 end
 200
 201 --- Retrieves the output of the "logread" command.
 202 -- @return      String containing the current log buffer
 203 function syslog()
 204         return luci.util.exec("logread")
 205 end
 206
 207 --- Retrieves the output of the "dmesg" command.
 208 -- @return      String containing the current log buffer
 209 function dmesg()
 210         return luci.util.exec("dmesg")
 211 end
 212
 213 --- Generates a random id with specified length.
 214 -- @param bytes Number of bytes for the unique id
 215 -- @return              String containing hex encoded id
 216 function uniqueid(bytes)
 217         local fp    = io.open("/dev/urandom")
 218         local chunk = { fp:read(bytes):byte(1, bytes) }
 219         fp:close()
 220
 221         local hex = ""
 222
 223         local pattern = "%02X"
 224         for i, byte in ipairs(chunk) do
 225                 hex = hex .. pattern:format(byte)
 226         end
 227
 228         return hex
 229 end
 230
 231 --- Returns the current system uptime stats.
 232 -- @return      String containing total uptime in seconds
 233 -- @return      String containing idle time in seconds
 234 function uptime()
 235         local loadavg = io.lines("/proc/uptime")()
 236         return loadavg:match("^(.-) (.-)$")
 237 end
 238
 239 --- LuCI system utilities / POSIX user group related functions.
 240 -- @class       module
 241 -- @name        luci.sys.group
 242 group = {}
 243
 244 --- Returns information about a POSIX user group.
 245 -- @class function
 246 -- @name                getgroup
 247 -- @param group Group ID or name of a system user group
 248 -- @return      Table with information about the requested group
 249 group.getgroup = posix.getgroup
 250
 251
 252 --- LuCI system utilities / network related functions.
 253 -- @class       module
 254 -- @name        luci.sys.net
 255 net = {}
 256
 257 --- Returns the current arp-table entries as two-dimensional table.
 258 -- @return      Table of table containing the current arp entries.
 259 --                      The following fields are defined for arp entry objects:
 260 --                      { "IP address", "HW address", "HW type", "Flags", "Mask", "Device" }
 261 function net.arptable()
 262         return _parse_delimited_table(io.lines("/proc/net/arp"), "%s%s+")
 263 end
 264
 265 --- Returns conntrack information
 266 -- @return      Table with the currently tracked IP connections
 267 function net.conntrack()
 268         local connt = {}
 269         if luci.fs.access("/proc/net/nf_conntrack") then
 270                 for line in io.lines("/proc/net/nf_conntrack") do
 271                         local entry, flags = _parse_mixed_record(line, " +")
 272                         entry.layer3 = flags[1]
 273                         entry.layer4 = flags[2]
 274                         for i=1, #entry do
 275                                 entry[i] = nil
 276                         end
 277
 278                         connt[#connt+1] = entry
 279                 end
 280         elseif luci.fs.access("/proc/net/ip_conntrack") then
 281                 for line in io.lines("/proc/net/ip_conntrack") do
 282                         local entry, flags = _parse_mixed_record(line, " +")
 283                         entry.layer3 = "ipv4"
 284                         entry.layer4 = flags[1]
 285                         for i=1, #entry do
 286                                 entry[i] = nil
 287                         end
 288
 289                         connt[#connt+1] = entry
 290                 end
 291         else
 292                 return nil
 293         end
 294         return connt
 295 end
 296
 297 --- Determine the current default route.
 298 -- @return      Table with the properties of the current default route.
 299 --                      The following fields are defined:
 300 --                      { "Mask", "RefCnt", "Iface", "Flags", "Window", "IRTT",
 301 --                        "MTU", "Gateway", "Destination", "Metric", "Use" }
 302 function net.defaultroute()
 303         local routes = net.routes()
 304         local route = nil
 305
 306         for i, r in pairs(luci.sys.net.routes()) do
 307                 if r.Destination == "00000000" and (not route or route.Metric > r.Metric) then
 308                         route = r
 309                 end
 310         end
 311
 312         return route
 313 end
 314
 315 --- Determine the names of available network interfaces.
 316 -- @return      Table containing all current interface names
 317 function net.devices()
 318         local devices = {}
 319         for line in io.lines("/proc/net/dev") do
 320                 table.insert(devices, line:match(" *(.-):"))
 321         end
 322         return devices
 323 end
 324
 325
 326 --- Return information about available network interfaces.
 327 -- @return      Table containing all current interface names and their information
 328 function net.deviceinfo()
 329         local devices = {}
 330         for line in io.lines("/proc/net/dev") do
 331                 local name, data = line:match("^ *(.-): *(.*)$")
 332                 if name and data then
 333                         devices[name] = luci.util.split(data, " +", nil, true)
 334                 end
 335         end
 336         return devices
 337 end
 338
 339
 340 -- Determine the MAC address belonging to the given IP address.
 341 -- @param ip    IPv4 address
 342 -- @return              String containing the MAC address or nil if it cannot be found
 343 function net.ip4mac(ip)
 344         local mac = nil
 345
 346         for i, l in ipairs(net.arptable()) do
 347                 if l["IP address"] == ip then
 348                         mac = l["HW address"]
 349                 end
 350         end
 351
 352         return mac
 353 end
 354
 355 --- Returns the current kernel routing table entries.
 356 -- @return      Table of tables with properties of the corresponding routes.
 357 --                      The following fields are defined for route entry tables:
 358 --                      { "Mask", "RefCnt", "Iface", "Flags", "Window", "IRTT",
 359 --                        "MTU", "Gateway", "Destination", "Metric", "Use" }
 360 function net.routes()
 361         return _parse_delimited_table(io.lines("/proc/net/route"))
 362 end
 363
 364 --- Returns the current ipv6 kernel routing table entries.
 365 -- @return      Table of tables with properties of the corresponding routes.
 366 --                      The following fields are defined for route entry tables:
 367 --                      { "src_ip", "src_prefix", "dst_ip", "dst_prefix", "nexthop_ip",
 368 --            "metric", "refcount", "usecount", "flags", "device" }
 369 function net.routes6()
 370         local routes = { }
 371
 372         for line in io.lines("/proc/net/ipv6_route") do
 373
 374                 local dst_ip, dst_prefix, src_ip, src_prefix, nexthop,
 375                           metric, refcnt, usecnt, flags, dev = line:match(
 376                         "([a-f0-9]+) ([a-f0-9]+) " ..
 377                         "([a-f0-9]+) ([a-f0-9]+) " ..
 378                         "([a-f0-9]+) ([a-f0-9]+) " ..
 379                         "([a-f0-9]+) ([a-f0-9]+) " ..
 380                         "([^%s]+) +([^%s]+)"
 381                 )
 382
 383                 src_ip = luci.ip.Hex(
 384                         src_ip, tonumber(src_prefix, 16),
 385                         luci.ip.FAMILY_INET6, false
 386                 )
 387
 388                 dst_ip = luci.ip.Hex(
 389                         dst_ip, tonumber(dst_prefix, 16),
 390                         luci.ip.FAMILY_INET6, false
 391                 )
 392
 393                 nexthop = luci.ip.Hex( nexthop, 128, luci.ip.FAMILY_INET6, false )
 394
 395                 routes[#routes+1] = {
 396                         src_ip     = src_ip:host():string(),
 397                         src_prefix = src_ip:prefix(),
 398                         dst_ip     = dst_ip:host():string(),
 399                         dst_prefix = dst_ip:prefix(),
 400                         nexthop_ip = nexthop:string(),
 401                         metric     = tonumber(metric, 16),
 402                         refcount   = tonumber(refcnt, 16),
 403                         usecount   = tonumber(usecnt, 16),
 404                         flags      = tonumber(flags), -- hex?
 405                         device     = dev
 406                 }
 407         end
 408
 409         return routes
 410 end
 411
 412 --- Tests whether the given host responds to ping probes.
 413 -- @param host  String containing a hostname or IPv4 address
 414 -- @return              Number containing 0 on success and >= 1 on error
 415 function net.pingtest(host)
 416         return os.execute("ping -c1 '"..host:gsub("'", '').."' >/dev/null 2>&1")
 417 end
 418
 419
 420 --- LuCI system utilities / process related functions.
 421 -- @class       module
 422 -- @name        luci.sys.process
 423 process = {}
 424
 425 --- Get the current process id.
 426 -- @class function
 427 -- @name  process.info
 428 -- @return      Number containing the current pid
 429 process.info = posix.getpid
 430
 431 --- Retrieve information about currently running processes.
 432 -- @return      Table containing process information
 433 function process.list()
 434         local data = {}
 435         local k
 436         local ps = luci.util.execi("top -bn1")
 437
 438         if not ps then
 439                 return
 440         end
 441
 442         while true do
 443                 local line = ps()
 444                 if not line then
 445                         return
 446                 end
 447
 448                 k = luci.util.split(luci.util.trim(line), "%s+", nil, true)
 449                 if k[1] == "PID" then
 450                         break
 451                 end
 452         end
 453
 454         for line in ps do
 455                 local row = {}
 456
 457                 line = luci.util.trim(line)
 458                 for i, value in ipairs(luci.util.split(line, "%s+", #k-1, true)) do
 459                         row[k[i]] = value
 460                 end
 461
 462                 local pid = tonumber(row[k[1]])
 463                 if pid then
 464                         data[pid] = row
 465                 end
 466         end
 467
 468         return data
 469 end
 470
 471 --- Set the gid of a process identified by given pid.
 472 -- @param pid   Number containing the process id
 473 -- @param gid   Number containing the Unix group id
 474 -- @return              Boolean indicating successful operation
 475 -- @return              String containing the error message if failed
 476 -- @return              Number containing the error code if failed
 477 function process.setgroup(pid, gid)
 478         return posix.setpid("g", pid, gid)
 479 end
 480
 481 --- Set the uid of a process identified by given pid.
 482 -- @param pid   Number containing the process id
 483 -- @param uid   Number containing the Unix user id
 484 -- @return              Boolean indicating successful operation
 485 -- @return              String containing the error message if failed
 486 -- @return              Number containing the error code if failed
 487 function process.setuser(pid, uid)
 488         return posix.setpid("u", pid, uid)
 489 end
 490
 491 --- Send a signal to a process identified by given pid.
 492 -- @class function
 493 -- @name  process.signal
 494 -- @param pid   Number containing the process id
 495 -- @param sig   Signal to send (default: 15 [SIGTERM])
 496 -- @return              Boolean indicating successful operation
 497 -- @return              Number containing the error code if failed
 498 process.signal = posix.kill
 499
 500
 501 --- LuCI system utilities / user related functions.
 502 -- @class       module
 503 -- @name        luci.sys.user
 504 user = {}
 505
 506 --- Retrieve user informations for given uid.
 507 -- @class               function
 508 -- @name                getuser
 509 -- @param uid   Number containing the Unix user id
 510 -- @return              Table containing the following fields:
 511 --                              { "uid", "gid", "name", "passwd", "dir", "shell", "gecos" }
 512 user.getuser = posix.getpasswd
 513
 514 --- Test whether given string matches the password of a given system user.
 515 -- @param username      String containing the Unix user name
 516 -- @param password      String containing the password to compare
 517 -- @return                      Boolean indicating wheather the passwords are equal
 518 function user.checkpasswd(username, password)
 519         local account = user.getuser(username)
 520
 521         if account then
 522                 local pwd = account.passwd
 523                 local shadowpw
 524                 if #pwd == 1 then
 525                         if luci.fs.stat("/etc/shadow") then
 526                                 if not pcall(function()
 527                                         for l in io.lines("/etc/shadow") do
 528                                                 shadowpw = l:match("^%s:([^:]+)" % username)
 529                                                 if shadowpw then
 530                                                         pwd = shadowpw
 531                                                         break
 532                                                 end
 533                                         end
 534                                 end) then
 535                                         return nil, "Unable to access shadow-file"
 536                                 end
 537                         end
 538
 539                         if pwd == "!" then
 540                                 return true
 541                         end
 542                 end
 543
 544                 if pwd and #pwd > 0 and password and #password > 0 then
 545                         return (pwd == posix.crypt(password, pwd))
 546                 end
 547         end
 548
 549         return false
 550 end
 551
 552 --- Change the password of given user.
 553 -- @param username      String containing the Unix user name
 554 -- @param password      String containing the password to compare
 555 -- @return                      Number containing 0 on success and >= 1 on error
 556 function user.setpasswd(username, password)
 557         if password then
 558                 password = password:gsub("'", "")
 559         end
 560
 561         if username then
 562                 username = username:gsub("'", "")
 563         end
 564
 565         local cmd = "(echo '"..password.."';sleep 1;echo '"..password.."')|"
 566         cmd = cmd .. "passwd '"..username.."' >/dev/null 2>&1"
 567         return os.execute(cmd)
 568 end
 569
 570
 571 --- LuCI system utilities / wifi related functions.
 572 -- @class       module
 573 -- @name        luci.sys.wifi
 574 wifi = {}
 575
 576 --- Get iwconfig output for all wireless devices.
 577 -- @return      Table of tables containing the iwconfing output for each wifi device
 578 function wifi.getiwconfig()
 579         local cnt = luci.util.exec("/usr/sbin/iwconfig 2>/dev/null")
 580         local iwc = {}
 581
 582         for i, l in pairs(luci.util.split(luci.util.trim(cnt), "\n\n")) do
 583                 local k = l:match("^(.-) ")
 584                 l = l:gsub("^(.-) +", "", 1)
 585                 if k then
 586                         local entry, flags = _parse_mixed_record(l)
 587                         if entry then
 588                                 entry.flags = flags
 589                         end
 590                         iwc[k] = entry
 591                 end
 592         end
 593
 594         return iwc
 595 end
 596
 597 --- Get iwlist scan output from all wireless devices.
 598 -- @return      Table of tables contaiing all scan results
 599 function wifi.iwscan(iface)
 600         local siface = iface or ""
 601         local cnt = luci.util.exec("iwlist "..siface.." scan 2>/dev/null")
 602         local iws = {}
 603
 604         for i, l in pairs(luci.util.split(luci.util.trim(cnt), "\n\n")) do
 605                 local k = l:match("^(.-) ")
 606                 l = l:gsub("^[^\n]+", "", 1)
 607                 l = luci.util.trim(l)
 608                 if k then
 609                         iws[k] = {}
 610                         for j, c in pairs(luci.util.split(l, "\n          Cell")) do
 611                                 c = c:gsub("^(.-)- ", "", 1)
 612                                 c = luci.util.split(c, "\n", 7)
 613                                 c = table.concat(c, "\n", 1)
 614                                 local entry, flags = _parse_mixed_record(c)
 615                                 if entry then
 616                                         entry.flags = flags
 617                                 end
 618                                 table.insert(iws[k], entry)
 619                         end
 620                 end
 621         end
 622
 623         return iface and (iws[iface] or {}) or iws
 624 end
 625
 626
 627 --- LuCI system utilities / init related functions.
 628 -- @class       module
 629 -- @name        luci.sys.init
 630 init = {}
 631 init.dir = "/etc/init.d/"
 632
 633 --- Get the names of all installed init scripts
 634 -- @return      Table containing the names of all inistalled init scripts
 635 function init.names()
 636         local names = { }
 637         for _, name in ipairs(luci.fs.glob(init.dir.."*")) do
 638                 names[#names+1] = luci.fs.basename(name)
 639         end
 640         return names
 641 end
 642
 643 --- Test whether the given init script is enabled
 644 -- @param name  Name of the init script
 645 -- @return              Boolean indicating whether init is enabled
 646 function init.enabled(name)
 647         if luci.fs.access(init.dir..name) then
 648                 return ( call(init.dir..name.." enabled") == 0 )
 649         end
 650         return false
 651 end
 652
 653 --- Get the index of he given init script
 654 -- @param name  Name of the init script
 655 -- @return              Numeric index value
 656 function init.index(name)
 657         if luci.fs.access(init.dir..name) then
 658                 return call("source "..init.dir..name.."; exit $START")
 659         end
 660 end
 661
 662 --- Enable the given init script
 663 -- @param name  Name of the init script
 664 -- @return              Boolean indicating success
 665 function init.enable(name)
 666         if luci.fs.access(init.dir..name) then
 667                 return ( call(init.dir..name.." enable") == 1 )
 668         end
 669 end
 670
 671 --- Disable the given init script
 672 -- @param name  Name of the init script
 673 -- @return              Boolean indicating success
 674 function init.disable(name)
 675         if luci.fs.access(init.dir..name) then
 676                 return ( call(init.dir..name.." disable") == 0 )
 677         end
 678 end
 679
 680
 681 -- Internal functions
 682
 683 function _parse_delimited_table(iter, delimiter)
 684         delimiter = delimiter or "%s+"
 685
 686         local data  = {}
 687         local trim  = luci.util.trim
 688         local split = luci.util.split
 689
 690         local keys = split(trim(iter()), delimiter, nil, true)
 691         for i, j in pairs(keys) do
 692                 keys[i] = trim(keys[i])
 693         end
 694
 695         for line in iter do
 696                 local row = {}
 697                 line = trim(line)
 698                 if #line > 0 then
 699                         for i, j in pairs(split(line, delimiter, nil, true)) do
 700                                 if keys[i] then
 701                                         row[keys[i]] = j
 702                                 end
 703                         end
 704                 end
 705                 table.insert(data, row)
 706         end
 707
 708         return data
 709 end
 710
 711 function _parse_mixed_record(cnt, delimiter)
 712         delimiter = delimiter or "  "
 713         local data = {}
 714         local flags = {}
 715
 716         for i, l in pairs(luci.util.split(luci.util.trim(cnt), "\n")) do
 717                 for j, f in pairs(luci.util.split(luci.util.trim(l), delimiter, nil, true)) do
 718                 local k, x, v = f:match('([^%s][^:=]+) *([:=]*) *"*([^\n"]*)"*')
 719
 720             if k then
 721                                 if x == "" then
 722                                         table.insert(flags, k)
 723                                 else
 724                         data[k] = v
 725                                 end
 726             end
 727         end
 728         end
 729
 730     return data, flags
 731 end