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util/serialization.lua @ 10390:82705ec87253 0.11
util.startup: Ensure prosody.paths are absolute (see #1430)
Normally these paths are injected into the installed 'prosody'
executable as absolute paths, but it is possible to override at least
the config path via environment variable or command line argument. This
makes sure a path relative to pwd stays relative to that instead of the
data directory.
author | Kim Alvefur <zash@zash.se> |
---|---|
date | Mon, 04 Nov 2019 00:29:49 +0100 |
parent | 10060:7a36b7ac309b |
child | 10061:5c71693c8345 |
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-- Prosody IM -- Copyright (C) 2008-2010 Matthew Wild -- Copyright (C) 2008-2010 Waqas Hussain -- Copyright (C) 2018 Kim Alvefur -- -- This project is MIT/X11 licensed. Please see the -- COPYING file in the source package for more information. -- local getmetatable = getmetatable; local next, type = next, type; local s_format = string.format; local s_gsub = string.gsub; local s_rep = string.rep; local s_char = string.char; local s_match = string.match; local t_concat = table.concat; local pcall = pcall; local envload = require"util.envload".envload; local pos_inf, neg_inf = math.huge, -math.huge; -- luacheck: ignore 143/math local m_type = math.type or function (n) return n % 1 == 0 and n <= 9007199254740992 and n >= -9007199254740992 and "integer" or "float"; end; local char_to_hex = {}; for i = 0,255 do char_to_hex[s_char(i)] = s_format("%02x", i); end local function to_hex(s) return (s_gsub(s, ".", char_to_hex)); end local function fatal_error(obj, why) error("Can't serialize "..type(obj) .. (why and ": ".. why or "")); end local function nonfatal_fallback(x, why) return s_format("{__type=%q,__error=%q}", type(x), why or "fail"); end local string_escapes = { ['\a'] = [[\a]]; ['\b'] = [[\b]]; ['\f'] = [[\f]]; ['\n'] = [[\n]]; ['\r'] = [[\r]]; ['\t'] = [[\t]]; ['\v'] = [[\v]]; ['\\'] = [[\\]]; ['\"'] = [[\"]]; ['\''] = [[\']]; } for i = 0, 255 do local c = s_char(i); if not string_escapes[c] then string_escapes[c] = s_format("\\%03d", i); end end local default_keywords = { ["do"] = true; ["and"] = true; ["else"] = true; ["break"] = true; ["if"] = true; ["end"] = true; ["goto"] = true; ["false"] = true; ["in"] = true; ["for"] = true; ["then"] = true; ["local"] = true; ["or"] = true; ["nil"] = true; ["true"] = true; ["until"] = true; ["elseif"] = true; ["function"] = true; ["not"] = true; ["repeat"] = true; ["return"] = true; ["while"] = true; }; local function new(opt) if type(opt) ~= "table" then opt = { preset = opt }; end local types = { table = true; string = true; number = true; boolean = true; ["nil"] = true; }; -- presets if opt.preset == "debug" then opt.preset = "oneline"; opt.freeze = true; opt.fatal = false; opt.fallback = nonfatal_fallback; opt.unquoted = true; end if opt.preset == "oneline" then opt.indentwith = opt.indentwith or ""; opt.itemstart = opt.itemstart or " "; opt.itemlast = opt.itemlast or ""; opt.tend = opt.tend or " }"; elseif opt.preset == "compact" then opt.indentwith = opt.indentwith or ""; opt.itemstart = opt.itemstart or ""; opt.itemlast = opt.itemlast or ""; opt.equals = opt.equals or "="; opt.unquoted = true; end local fallback = opt.fallback or opt.fatal == false and nonfatal_fallback or fatal_error; local function ser(v) return (types[type(v)] or fallback)(v); end local keywords = opt.keywords or default_keywords; -- indented local indentwith = opt.indentwith or "\t"; local itemstart = opt.itemstart or "\n"; local itemsep = opt.itemsep or ";"; local itemlast = opt.itemlast or ";\n"; local tstart = opt.tstart or "{"; local tend = opt.tend or "}"; local kstart = opt.kstart or "["; local kend = opt.kend or "]"; local equals = opt.equals or " = "; local unquoted = opt.unquoted == true and "^[%a_][%w_]*$" or opt.unquoted; local hex = opt.hex; local freeze = opt.freeze; local maxdepth = opt.maxdepth or 127; local multirefs = opt.multiref; -- serialize one table, recursively -- t - table being serialized -- o - array where tokens are added, concatenate to get final result -- - also used to detect cycles -- l - position in o of where to insert next token -- d - depth, used for indentation local function serialize_table(t, o, l, d) if o[t] then o[l], l = fallback(t, "table has multiple references"), l + 1; return l; elseif d > maxdepth then o[l], l = fallback(t, "max table depth reached"), l + 1; return l; end -- Keep track of table loops local ot = t; -- reference pre-freeze o[t] = true; o[ot] = true; if freeze == true then -- opportunity to do pre-serialization local mt = getmetatable(t); if type(mt) == "table" then local tag = mt.__name; local fr = mt.__freeze; if type(fr) == "function" then t = fr(t); if type(tag) == "string" then o[l], l = tag, l + 1; end end end end o[l], l = tstart, l + 1; local indent = s_rep(indentwith, d); local numkey = 1; local ktyp, vtyp; for k,v in next,t do o[l], l = itemstart, l + 1; o[l], l = indent, l + 1; ktyp, vtyp = type(k), type(v); if k == numkey then -- next index in array part -- assuming that these are found in order numkey = numkey + 1; elseif unquoted and ktyp == "string" and not keywords[k] and s_match(k, unquoted) then -- unquoted keys o[l], l = k, l + 1; o[l], l = equals, l + 1; else -- quoted keys o[l], l = kstart, l + 1; if ktyp == "table" then l = serialize_table(k, o, l, d+1); else o[l], l = ser(k), l + 1; end -- = o[l], o[l+1], l = kend, equals, l + 2; end -- the value if vtyp == "table" then l = serialize_table(v, o, l, d+1); else o[l], l = ser(v), l + 1; end -- last item? if next(t, k) ~= nil then o[l], l = itemsep, l + 1; else o[l], l = itemlast, l + 1; end end if next(t) ~= nil then o[l], l = s_rep(indentwith, d-1), l + 1; end o[l], l = tend, l +1; if multirefs then o[t] = nil; o[ot] = nil; end return l; end function types.table(t) local o = {}; serialize_table(t, o, 1, 1); return t_concat(o); end local function serialize_string(s) return '"' .. s_gsub(s, "[%z\1-\31\"\'\\\127-\255]", string_escapes) .. '"'; end if type(hex) == "string" then function types.string(s) local esc = serialize_string(s); if #esc > (#s*2+2+#hex) then return hex .. '"' .. to_hex(s) .. '"'; end return esc; end else types.string = serialize_string; end function types.number(t) if m_type(t) == "integer" then return s_format("%d", t); elseif t == pos_inf then return "(1/0)"; elseif t == neg_inf then return "(-1/0)"; elseif t ~= t then return "(0/0)"; end return s_format("%.18g", t); end -- Are these faster than tostring? types["nil"] = function() return "nil"; end function types.boolean(t) return t and "true" or "false"; end return ser; end local function deserialize(str) if type(str) ~= "string" then return nil; end str = "return "..str; local f, err = envload(str, "=serialized data", {}); if not f then return nil, err; end local success, ret = pcall(f); if not success then return nil, ret; end return ret; end local default = new(); return { new = new; serialize = function (x, opt) if opt == nil then return default(x); else return new(opt)(x); end end; deserialize = deserialize; };