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Diffstat (limited to 'modules/base/luasrc/util.lua')
| -rw-r--r-- | modules/base/luasrc/util.lua | 791 |
1 files changed, 791 insertions, 0 deletions
diff --git a/modules/base/luasrc/util.lua b/modules/base/luasrc/util.lua new file mode 100644 index 0000000000..da761e219a --- /dev/null +++ b/modules/base/luasrc/util.lua @@ -0,0 +1,791 @@ +--[[ +LuCI - Utility library + +Description: +Several common useful Lua functions + +License: +Copyright 2008 Steven Barth <steven@midlink.org> + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. + +]]-- + +local io = require "io" +local math = require "math" +local table = require "table" +local debug = require "debug" +local ldebug = require "luci.debug" +local string = require "string" +local coroutine = require "coroutine" +local tparser = require "luci.template.parser" + +local getmetatable, setmetatable = getmetatable, setmetatable +local rawget, rawset, unpack = rawget, rawset, unpack +local tostring, type, assert = tostring, type, assert +local ipairs, pairs, next, loadstring = ipairs, pairs, next, loadstring +local require, pcall, xpcall = require, pcall, xpcall +local collectgarbage, get_memory_limit = collectgarbage, get_memory_limit + +--- LuCI utility functions. +module "luci.util" + +-- +-- Pythonic string formatting extension +-- +getmetatable("").__mod = function(a, b) + if not b then + return a + elseif type(b) == "table" then + for k, _ in pairs(b) do if type(b[k]) == "userdata" then b[k] = tostring(b[k]) end end + return a:format(unpack(b)) + else + if type(b) == "userdata" then b = tostring(b) end + return a:format(b) + end +end + + +-- +-- Class helper routines +-- + +-- Instantiates a class +local function _instantiate(class, ...) + local inst = setmetatable({}, {__index = class}) + + if inst.__init__ then + inst:__init__(...) + end + + return inst +end + +--- Create a Class object (Python-style object model). +-- The class object can be instantiated by calling itself. +-- Any class functions or shared parameters can be attached to this object. +-- Attaching a table to the class object makes this table shared between +-- all instances of this class. For object parameters use the __init__ function. +-- Classes can inherit member functions and values from a base class. +-- Class can be instantiated by calling them. All parameters will be passed +-- to the __init__ function of this class - if such a function exists. +-- The __init__ function must be used to set any object parameters that are not shared +-- with other objects of this class. Any return values will be ignored. +-- @param base The base class to inherit from (optional) +-- @return A class object +-- @see instanceof +-- @see clone +function class(base) + return setmetatable({}, { + __call = _instantiate, + __index = base + }) +end + +--- Test whether the given object is an instance of the given class. +-- @param object Object instance +-- @param class Class object to test against +-- @return Boolean indicating whether the object is an instance +-- @see class +-- @see clone +function instanceof(object, class) + local meta = getmetatable(object) + while meta and meta.__index do + if meta.__index == class then + return true + end + meta = getmetatable(meta.__index) + end + return false +end + + +-- +-- Scope manipulation routines +-- + +local tl_meta = { + __mode = "k", + + __index = function(self, key) + local t = rawget(self, coxpt[coroutine.running()] + or coroutine.running() or 0) + return t and t[key] + end, + + __newindex = function(self, key, value) + local c = coxpt[coroutine.running()] or coroutine.running() or 0 + if not rawget(self, c) then + rawset(self, c, { [key] = value }) + else + rawget(self, c)[key] = value + end + end +} + +--- Create a new or get an already existing thread local store associated with +-- the current active coroutine. A thread local store is private a table object +-- whose values can't be accessed from outside of the running coroutine. +-- @return Table value representing the corresponding thread local store +function threadlocal(tbl) + return setmetatable(tbl or {}, tl_meta) +end + + +-- +-- Debugging routines +-- + +--- Write given object to stderr. +-- @param obj Value to write to stderr +-- @return Boolean indicating whether the write operation was successful +function perror(obj) + return io.stderr:write(tostring(obj) .. "\n") +end + +--- Recursively dumps a table to stdout, useful for testing and debugging. +-- @param t Table value to dump +-- @param maxdepth Maximum depth +-- @return Always nil +function dumptable(t, maxdepth, i, seen) + i = i or 0 + seen = seen or setmetatable({}, {__mode="k"}) + + for k,v in pairs(t) do + perror(string.rep("\t", i) .. tostring(k) .. "\t" .. tostring(v)) + if type(v) == "table" and (not maxdepth or i < maxdepth) then + if not seen[v] then + seen[v] = true + dumptable(v, maxdepth, i+1, seen) + else + perror(string.rep("\t", i) .. "*** RECURSION ***") + end + end + end +end + + +-- +-- String and data manipulation routines +-- + +--- Create valid XML PCDATA from given string. +-- @param value String value containing the data to escape +-- @return String value containing the escaped data +function pcdata(value) + return value and tparser.pcdata(tostring(value)) +end + +--- Strip HTML tags from given string. +-- @param value String containing the HTML text +-- @return String with HTML tags stripped of +function striptags(value) + return value and tparser.striptags(tostring(value)) +end + +--- Splits given string on a defined separator sequence and return a table +-- containing the resulting substrings. The optional max parameter specifies +-- the number of bytes to process, regardless of the actual length of the given +-- string. The optional last parameter, regex, specifies whether the separator +-- sequence is interpreted as regular expression. +-- @param str String value containing the data to split up +-- @param pat String with separator pattern (optional, defaults to "\n") +-- @param max Maximum times to split (optional) +-- @param regex Boolean indicating whether to interpret the separator +-- pattern as regular expression (optional, default is false) +-- @return Table containing the resulting substrings +function split(str, pat, max, regex) + pat = pat or "\n" + max = max or #str + + local t = {} + local c = 1 + + if #str == 0 then + return {""} + end + + if #pat == 0 then + return nil + end + + if max == 0 then + return str + end + + repeat + local s, e = str:find(pat, c, not regex) + max = max - 1 + if s and max < 0 then + t[#t+1] = str:sub(c) + else + t[#t+1] = str:sub(c, s and s - 1) + end + c = e and e + 1 or #str + 1 + until not s or max < 0 + + return t +end + +--- Remove leading and trailing whitespace from given string value. +-- @param str String value containing whitespace padded data +-- @return String value with leading and trailing space removed +function trim(str) + return (str:gsub("^%s*(.-)%s*$", "%1")) +end + +--- Count the occurences of given substring in given string. +-- @param str String to search in +-- @param pattern String containing pattern to find +-- @return Number of found occurences +function cmatch(str, pat) + local count = 0 + for _ in str:gmatch(pat) do count = count + 1 end + return count +end + +--- Return a matching iterator for the given value. The iterator will return +-- one token per invocation, the tokens are separated by whitespace. If the +-- input value is a table, it is transformed into a string first. A nil value +-- will result in a valid interator which aborts with the first invocation. +-- @param val The value to scan (table, string or nil) +-- @return Iterator which returns one token per call +function imatch(v) + if type(v) == "table" then + local k = nil + return function() + k = next(v, k) + return v[k] + end + + elseif type(v) == "number" or type(v) == "boolean" then + local x = true + return function() + if x then + x = false + return tostring(v) + end + end + + elseif type(v) == "userdata" or type(v) == "string" then + return tostring(v):gmatch("%S+") + end + + return function() end +end + +--- Parse certain units from the given string and return the canonical integer +-- value or 0 if the unit is unknown. Upper- or lower case is irrelevant. +-- Recognized units are: +-- o "y" - one year (60*60*24*366) +-- o "m" - one month (60*60*24*31) +-- o "w" - one week (60*60*24*7) +-- o "d" - one day (60*60*24) +-- o "h" - one hour (60*60) +-- o "min" - one minute (60) +-- o "kb" - one kilobyte (1024) +-- o "mb" - one megabyte (1024*1024) +-- o "gb" - one gigabyte (1024*1024*1024) +-- o "kib" - one si kilobyte (1000) +-- o "mib" - one si megabyte (1000*1000) +-- o "gib" - one si gigabyte (1000*1000*1000) +-- @param ustr String containing a numerical value with trailing unit +-- @return Number containing the canonical value +function parse_units(ustr) + + local val = 0 + + -- unit map + local map = { + -- date stuff + y = 60 * 60 * 24 * 366, + m = 60 * 60 * 24 * 31, + w = 60 * 60 * 24 * 7, + d = 60 * 60 * 24, + h = 60 * 60, + min = 60, + + -- storage sizes + kb = 1024, + mb = 1024 * 1024, + gb = 1024 * 1024 * 1024, + + -- storage sizes (si) + kib = 1000, + mib = 1000 * 1000, + gib = 1000 * 1000 * 1000 + } + + -- parse input string + for spec in ustr:lower():gmatch("[0-9%.]+[a-zA-Z]*") do + + local num = spec:gsub("[^0-9%.]+$","") + local spn = spec:gsub("^[0-9%.]+", "") + + if map[spn] or map[spn:sub(1,1)] then + val = val + num * ( map[spn] or map[spn:sub(1,1)] ) + else + val = val + num + end + end + + + return val +end + +-- also register functions above in the central string class for convenience +string.pcdata = pcdata +string.striptags = striptags +string.split = split +string.trim = trim +string.cmatch = cmatch +string.parse_units = parse_units + + +--- Appends numerically indexed tables or single objects to a given table. +-- @param src Target table +-- @param ... Objects to insert +-- @return Target table +function append(src, ...) + for i, a in ipairs({...}) do + if type(a) == "table" then + for j, v in ipairs(a) do + src[#src+1] = v + end + else + src[#src+1] = a + end + end + return src +end + +--- Combines two or more numerically indexed tables and single objects into one table. +-- @param tbl1 Table value to combine +-- @param tbl2 Table value to combine +-- @param ... More tables to combine +-- @return Table value containing all values of given tables +function combine(...) + return append({}, ...) +end + +--- Checks whether the given table contains the given value. +-- @param table Table value +-- @param value Value to search within the given table +-- @return Boolean indicating whether the given value occurs within table +function contains(table, value) + for k, v in pairs(table) do + if value == v then + return k + end + end + return false +end + +--- Update values in given table with the values from the second given table. +-- Both table are - in fact - merged together. +-- @param t Table which should be updated +-- @param updates Table containing the values to update +-- @return Always nil +function update(t, updates) + for k, v in pairs(updates) do + t[k] = v + end +end + +--- Retrieve all keys of given associative table. +-- @param t Table to extract keys from +-- @return Sorted table containing the keys +function keys(t) + local keys = { } + if t then + for k, _ in kspairs(t) do + keys[#keys+1] = k + end + end + return keys +end + +--- Clones the given object and return it's copy. +-- @param object Table value to clone +-- @param deep Boolean indicating whether to do recursive cloning +-- @return Cloned table value +function clone(object, deep) + local copy = {} + + for k, v in pairs(object) do + if deep and type(v) == "table" then + v = clone(v, deep) + end + copy[k] = v + end + + return setmetatable(copy, getmetatable(object)) +end + + +--- Create a dynamic table which automatically creates subtables. +-- @return Dynamic Table +function dtable() + return setmetatable({}, { __index = + function(tbl, key) + return rawget(tbl, key) + or rawget(rawset(tbl, key, dtable()), key) + end + }) +end + + +-- Serialize the contents of a table value. +function _serialize_table(t, seen) + assert(not seen[t], "Recursion detected.") + seen[t] = true + + local data = "" + local idata = "" + local ilen = 0 + + for k, v in pairs(t) do + if type(k) ~= "number" or k < 1 or math.floor(k) ~= k or ( k - #t ) > 3 then + k = serialize_data(k, seen) + v = serialize_data(v, seen) + data = data .. ( #data > 0 and ", " or "" ) .. + '[' .. k .. '] = ' .. v + elseif k > ilen then + ilen = k + end + end + + for i = 1, ilen do + local v = serialize_data(t[i], seen) + idata = idata .. ( #idata > 0 and ", " or "" ) .. v + end + + return idata .. ( #data > 0 and #idata > 0 and ", " or "" ) .. data +end + +--- Recursively serialize given data to lua code, suitable for restoring +-- with loadstring(). +-- @param val Value containing the data to serialize +-- @return String value containing the serialized code +-- @see restore_data +-- @see get_bytecode +function serialize_data(val, seen) + seen = seen or setmetatable({}, {__mode="k"}) + + if val == nil then + return "nil" + elseif type(val) == "number" then + return val + elseif type(val) == "string" then + return "%q" % val + elseif type(val) == "boolean" then + return val and "true" or "false" + elseif type(val) == "function" then + return "loadstring(%q)" % get_bytecode(val) + elseif type(val) == "table" then + return "{ " .. _serialize_table(val, seen) .. " }" + else + return '"[unhandled data type:' .. type(val) .. ']"' + end +end + +--- Restore data previously serialized with serialize_data(). +-- @param str String containing the data to restore +-- @return Value containing the restored data structure +-- @see serialize_data +-- @see get_bytecode +function restore_data(str) + return loadstring("return " .. str)() +end + + +-- +-- Byte code manipulation routines +-- + +--- Return the current runtime bytecode of the given data. The byte code +-- will be stripped before it is returned. +-- @param val Value to return as bytecode +-- @return String value containing the bytecode of the given data +function get_bytecode(val) + local code + + if type(val) == "function" then + code = string.dump(val) + else + code = string.dump( loadstring( "return " .. serialize_data(val) ) ) + end + + return code -- and strip_bytecode(code) +end + +--- Strips unnescessary lua bytecode from given string. Information like line +-- numbers and debugging numbers will be discarded. Original version by +-- Peter Cawley (http://lua-users.org/lists/lua-l/2008-02/msg01158.html) +-- @param code String value containing the original lua byte code +-- @return String value containing the stripped lua byte code +function strip_bytecode(code) + local version, format, endian, int, size, ins, num, lnum = code:byte(5, 12) + local subint + if endian == 1 then + subint = function(code, i, l) + local val = 0 + for n = l, 1, -1 do + val = val * 256 + code:byte(i + n - 1) + end + return val, i + l + end + else + subint = function(code, i, l) + local val = 0 + for n = 1, l, 1 do + val = val * 256 + code:byte(i + n - 1) + end + return val, i + l + end + end + + local function strip_function(code) + local count, offset = subint(code, 1, size) + local stripped = { string.rep("\0", size) } + local dirty = offset + count + offset = offset + count + int * 2 + 4 + offset = offset + int + subint(code, offset, int) * ins + count, offset = subint(code, offset, int) + for n = 1, count do + local t + t, offset = subint(code, offset, 1) + if t == 1 then + offset = offset + 1 + elseif t == 4 then + offset = offset + size + subint(code, offset, size) + elseif t == 3 then + offset = offset + num + elseif t == 254 or t == 9 then + offset = offset + lnum + end + end + count, offset = subint(code, offset, int) + stripped[#stripped+1] = code:sub(dirty, offset - 1) + for n = 1, count do + local proto, off = strip_function(code:sub(offset, -1)) + stripped[#stripped+1] = proto + offset = offset + off - 1 + end + offset = offset + subint(code, offset, int) * int + int + count, offset = subint(code, offset, int) + for n = 1, count do + offset = offset + subint(code, offset, size) + size + int * 2 + end + count, offset = subint(code, offset, int) + for n = 1, count do + offset = offset + subint(code, offset, size) + size + end + stripped[#stripped+1] = string.rep("\0", int * 3) + return table.concat(stripped), offset + end + + return code:sub(1,12) .. strip_function(code:sub(13,-1)) +end + + +-- +-- Sorting iterator functions +-- + +function _sortiter( t, f ) + local keys = { } + + local k, v + for k, v in pairs(t) do + keys[#keys+1] = k + end + + local _pos = 0 + + table.sort( keys, f ) + + return function() + _pos = _pos + 1 + if _pos <= #keys then + return keys[_pos], t[keys[_pos]], _pos + end + end +end + +--- Return a key, value iterator which returns the values sorted according to +-- the provided callback function. +-- @param t The table to iterate +-- @param f A callback function to decide the order of elements +-- @return Function value containing the corresponding iterator +function spairs(t,f) + return _sortiter( t, f ) +end + +--- Return a key, value iterator for the given table. +-- The table pairs are sorted by key. +-- @param t The table to iterate +-- @return Function value containing the corresponding iterator +function kspairs(t) + return _sortiter( t ) +end + +--- Return a key, value iterator for the given table. +-- The table pairs are sorted by value. +-- @param t The table to iterate +-- @return Function value containing the corresponding iterator +function vspairs(t) + return _sortiter( t, function (a,b) return t[a] < t[b] end ) +end + + +-- +-- System utility functions +-- + +--- Test whether the current system is operating in big endian mode. +-- @return Boolean value indicating whether system is big endian +function bigendian() + return string.byte(string.dump(function() end), 7) == 0 +end + +--- Execute given commandline and gather stdout. +-- @param command String containing command to execute +-- @return String containing the command's stdout +function exec(command) + local pp = io.popen(command) + local data = pp:read("*a") + pp:close() + + return data +end + +--- Return a line-buffered iterator over the output of given command. +-- @param command String containing the command to execute +-- @return Iterator +function execi(command) + local pp = io.popen(command) + + return pp and function() + local line = pp:read() + + if not line then + pp:close() + end + + return line + end +end + +-- Deprecated +function execl(command) + local pp = io.popen(command) + local line = "" + local data = {} + + while true do + line = pp:read() + if (line == nil) then break end + data[#data+1] = line + end + pp:close() + + return data +end + +--- Returns the absolute path to LuCI base directory. +-- @return String containing the directory path +function libpath() + return require "nixio.fs".dirname(ldebug.__file__) +end + + +-- +-- Coroutine safe xpcall and pcall versions modified for Luci +-- original version: +-- coxpcall 1.13 - Copyright 2005 - Kepler Project (www.keplerproject.org) +-- +-- Copyright © 2005 Kepler Project. +-- Permission is hereby granted, free of charge, to any person obtaining a +-- copy of this software and associated documentation files (the "Software"), +-- to deal in the Software without restriction, including without limitation +-- the rights to use, copy, modify, merge, publish, distribute, sublicense, +-- and/or sell copies of the Software, and to permit persons to whom the +-- Software is furnished to do so, subject to the following conditions: +-- +-- The above copyright notice and this permission notice shall be +-- included in all copies or substantial portions of the Software. +-- +-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +-- EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES +-- OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. +-- IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, +-- DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, +-- TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE +-- OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + +local performResume, handleReturnValue +local oldpcall, oldxpcall = pcall, xpcall +coxpt = {} +setmetatable(coxpt, {__mode = "kv"}) + +-- Identity function for copcall +local function copcall_id(trace, ...) + return ... +end + +--- This is a coroutine-safe drop-in replacement for Lua's "xpcall"-function +-- @param f Lua function to be called protected +-- @param err Custom error handler +-- @param ... Parameters passed to the function +-- @return A boolean whether the function call succeeded and the return +-- values of either the function or the error handler +function coxpcall(f, err, ...) + local res, co = oldpcall(coroutine.create, f) + if not res then + local params = {...} + local newf = function() return f(unpack(params)) end + co = coroutine.create(newf) + end + local c = coroutine.running() + coxpt[co] = coxpt[c] or c or 0 + + return performResume(err, co, ...) +end + +--- This is a coroutine-safe drop-in replacement for Lua's "pcall"-function +-- @param f Lua function to be called protected +-- @param ... Parameters passed to the function +-- @return A boolean whether the function call succeeded and the returns +-- values of the function or the error object +function copcall(f, ...) + return coxpcall(f, copcall_id, ...) +end + +-- Handle return value of protected call +function handleReturnValue(err, co, status, ...) + if not status then + return false, err(debug.traceback(co, (...)), ...) + end + + if coroutine.status(co) ~= 'suspended' then + return true, ... + end + + return performResume(err, co, coroutine.yield(...)) +end + +-- Resume execution of protected function call +function performResume(err, co, ...) + return handleReturnValue(err, co, coroutine.resume(co, ...)) +end |