Compressing Luafiles added

init.lua

@@ -15,6 +15,8 @@ bootledtimer:start()
 
 local blacklistfile="init.lua config.lua config.lua.new webpage.html"
 function recompileAll()
+    -- 3, discard Local, Upvalue and line-number debug info
+    node.stripdebug(3)
     -- compile all files
     l = file.list();
     for k,_ in pairs(l) do
@@ -77,7 +79,7 @@ initTimer:register(5000, tmr.ALARM_SINGLE, function (t)
             dofile("config.lua")
             normalOperation()
         else
-            mydofile("webserver")
+            mydofile("websrv_diet")
             -- Logic for inital setup
             startSetupMode()
         end

tools/Readme.md

@@ -2,3 +2,12 @@
 **Not** supported with python 3.x
 ## Source:
 https://github.com/4refr0nt/luatool/tree/master/luatool
+# LuaSrcDiet
+LuaSrcDiet reduces the size of Lua 5.1+ source files by aggressively removing all unnecessary whitespace and comments, optimizing constant tokens, and renaming local variables to shorter names.
+* https://github.com/jirutka/luasrcdiet
+
+## Source:
+https://raw.githubusercontent.com/jirutka/luasrcdiet/master/bin/luasrcdiet
+
+## Example:
+ bin/luasrcdiet ../webserver.lua -o ../websrv_diet.lua

tools/bin/luasrcdiet

@@ -0,0 +1,653 @@
+#!/usr/bin/env lua
+---------
+-- LuaSrcDiet
+--
+-- Compresses Lua source code by removing unnecessary characters.
+-- For Lua 5.1+ source code.
+--
+-- **Notes:**
+--
+-- * Remember to update version and date information below (MSG_TITLE).
+-- * TODO: passing data tables around is a horrific mess.
+-- * TODO: to implement pcall() to properly handle lexer etc. errors.
+-- * TODO: need some automatic testing for a semblance of sanity.
+-- * TODO: the plugin module is highly experimental and unstable.
+----
+local equiv = require "luasrcdiet.equiv"
+local fs = require "luasrcdiet.fs"
+local llex = require "luasrcdiet.llex"
+local lparser = require "luasrcdiet.lparser"
+local luasrcdiet = require "luasrcdiet.init"
+local optlex = require "luasrcdiet.optlex"
+local optparser = require "luasrcdiet.optparser"
+
+local byte = string.byte
+local concat = table.concat
+local find = string.find
+local fmt = string.format
+local gmatch = string.gmatch
+local match = string.match
+local print = print
+local rep = string.rep
+local sub = string.sub
+
+local plugin
+
+local LUA_VERSION = match(_VERSION, " (5%.[123])$") or "5.1"
+
+-- Is --opt-binequiv available for this Lua version?
+local BIN_EQUIV_AVAIL = LUA_VERSION == "5.1" and not package.loaded.jit
+
+
+---------------------- Messages and textual data ----------------------
+
+local MSG_TITLE = fmt([[
+LuaSrcDiet: Puts your Lua 5.1+ source code on a diet
+Version %s <%s>
+]], luasrcdiet._VERSION, luasrcdiet._HOMEPAGE)
+
+local MSG_USAGE = [[
+usage: luasrcdiet [options] [filenames]
+
+example:
+  >luasrcdiet myscript.lua -o myscript_.lua
+
+options:
+  -v, --version       prints version information
+  -h, --help          prints usage information
+  -o <file>           specify file name to write output
+  -s <suffix>         suffix for output files (default '_')
+  --keep <msg>        keep block comment with <msg> inside
+  --plugin <module>   run <module> in plugin/ directory
+  -                   stop handling arguments
+
+  (optimization levels)
+  --none              all optimizations off (normalizes EOLs only)
+  --basic             lexer-based optimizations only
+  --maximum           maximize reduction of source
+
+  (informational)
+  --quiet             process files quietly
+  --read-only         read file and print token stats only
+  --dump-lexer        dump raw tokens from lexer to stdout
+  --dump-parser       dump variable tracking tables from parser
+  --details           extra info (strings, numbers, locals)
+
+features (to disable, insert 'no' prefix like --noopt-comments):
+%s
+default settings:
+%s]]
+
+-- Optimization options, for ease of switching on and off.
+--
+-- * Positive to enable optimization, negative (no) to disable.
+-- * These options should follow --opt-* and --noopt-* style for now.
+local OPTION = [[
+--opt-comments,'remove comments and block comments'
+--opt-whitespace,'remove whitespace excluding EOLs'
+--opt-emptylines,'remove empty lines'
+--opt-eols,'all above, plus remove unnecessary EOLs'
+--opt-strings,'optimize strings and long strings'
+--opt-numbers,'optimize numbers'
+--opt-locals,'optimize local variable names'
+--opt-entropy,'tries to reduce symbol entropy of locals'
+--opt-srcequiv,'insist on source (lexer stream) equivalence'
+--opt-binequiv,'insist on binary chunk equivalence (only for PUC Lua 5.1)'
+--opt-experimental,'apply experimental optimizations'
+]]
+
+-- Preset configuration.
+local DEFAULT_CONFIG = [[
+  --opt-comments --opt-whitespace --opt-emptylines
+  --opt-numbers --opt-locals
+  --opt-srcequiv --noopt-binequiv
+]]
+-- Override configurations: MUST explicitly enable/disable everything.
+local BASIC_CONFIG = [[
+  --opt-comments --opt-whitespace --opt-emptylines
+  --noopt-eols --noopt-strings --noopt-numbers
+  --noopt-locals --noopt-entropy
+  --opt-srcequiv --noopt-binequiv
+]]
+local MAXIMUM_CONFIG = [[
+  --opt-comments --opt-whitespace --opt-emptylines
+  --opt-eols --opt-strings --opt-numbers
+  --opt-locals --opt-entropy
+  --opt-srcequiv
+]] .. (BIN_EQUIV_AVAIL and ' --opt-binequiv' or ' --noopt-binequiv')
+
+local NONE_CONFIG = [[
+  --noopt-comments --noopt-whitespace --noopt-emptylines
+  --noopt-eols --noopt-strings --noopt-numbers
+  --noopt-locals --noopt-entropy
+  --opt-srcequiv --noopt-binequiv
+]]
+
+local DEFAULT_SUFFIX = "_"      -- default suffix for file renaming
+local PLUGIN_SUFFIX = "luasrcdiet.plugin." -- relative location of plugins
+
+
+------------- Startup and initialize option list handling -------------
+
+--- Simple error message handler; change to error if traceback wanted.
+--
+-- @tparam string msg The message to print.
+local function die(msg)
+  print("LuaSrcDiet (error): "..msg); os.exit(1)
+end
+--die = error--DEBUG
+
+-- Prepare text for list of optimizations, prepare lookup table.
+local MSG_OPTIONS = ""
+do
+  local WIDTH = 24
+  local o = {}
+  for op, desc in gmatch(OPTION, "%s*([^,]+),'([^']+)'") do
+    local msg = "  "..op
+    msg = msg..rep(" ", WIDTH - #msg)..desc.."\n"
+    MSG_OPTIONS = MSG_OPTIONS..msg
+    o[op] = true
+    o["--no"..sub(op, 3)] = true
+  end
+  OPTION = o  -- replace OPTION with lookup table
+end
+
+MSG_USAGE = fmt(MSG_USAGE, MSG_OPTIONS, DEFAULT_CONFIG)
+
+
+--------- Global variable initialization, option set handling ---------
+
+local suffix = DEFAULT_SUFFIX           -- file suffix
+local option = {}                       -- program options
+local stat_c, stat_l                    -- statistics tables
+
+--- Sets option lookup table based on a text list of options.
+--
+-- Note: additional forced settings for --opt-eols is done in optlex.lua.
+--
+-- @tparam string CONFIG
+local function set_options(CONFIG)
+  for op in gmatch(CONFIG, "(%-%-%S+)") do
+    if sub(op, 3, 4) == "no" and        -- handle negative options
+       OPTION["--"..sub(op, 5)] then
+      option[sub(op, 5)] = false
+    else
+      option[sub(op, 3)] = true
+    end
+  end
+end
+
+
+-------------------------- Support functions --------------------------
+
+-- List of token types, parser-significant types are up to TTYPE_GRAMMAR
+-- while the rest are not used by parsers; arranged for stats display.
+local TTYPES = {
+  "TK_KEYWORD", "TK_NAME", "TK_NUMBER",         -- grammar
+  "TK_STRING", "TK_LSTRING", "TK_OP",
+  "TK_EOS",
+  "TK_COMMENT", "TK_LCOMMENT",                  -- non-grammar
+  "TK_EOL", "TK_SPACE",
+}
+local TTYPE_GRAMMAR = 7
+
+local EOLTYPES = {                      -- EOL names for token dump
+  ["\n"] = "LF", ["\r"] = "CR",
+  ["\n\r"] = "LFCR", ["\r\n"] = "CRLF",
+}
+
+--- Reads source code from the file.
+--
+-- @tparam string fname Path of the file to read.
+-- @treturn string Content of the file.
+local function load_file(fname)
+  local data, err = fs.read_file(fname, "rb")
+  if not data then die(err) end
+  return data
+end
+
+--- Saves source code to the file.
+--
+-- @tparam string fname Path of the destination file.
+-- @tparam string dat The data to write into the file.
+local function save_file(fname, dat)
+  local ok, err = fs.write_file(fname, dat, "wb")
+  if not ok then die(err) end
+end
+
+
+------------------ Functions to deal with statistics ------------------
+
+--- Initializes the statistics table.
+local function stat_init()
+  stat_c, stat_l = {}, {}
+  for i = 1, #TTYPES do
+    local ttype = TTYPES[i]
+    stat_c[ttype], stat_l[ttype] = 0, 0
+  end
+end
+
+--- Adds a token to the statistics table.
+--
+-- @tparam string tok The token.
+-- @param seminfo
+local function stat_add(tok, seminfo)
+  stat_c[tok] = stat_c[tok] + 1
+  stat_l[tok] = stat_l[tok] + #seminfo
+end
+
+--- Computes totals for the statistics table, returns average table.
+--
+-- @treturn table
+local function stat_calc()
+  local function avg(c, l)                      -- safe average function
+    if c == 0 then return 0 end
+    return l / c
+  end
+  local stat_a = {}
+  local c, l = 0, 0
+  for i = 1, TTYPE_GRAMMAR do                   -- total grammar tokens
+    local ttype = TTYPES[i]
+    c = c + stat_c[ttype]; l = l + stat_l[ttype]
+  end
+  stat_c.TOTAL_TOK, stat_l.TOTAL_TOK = c, l
+  stat_a.TOTAL_TOK = avg(c, l)
+  c, l = 0, 0
+  for i = 1, #TTYPES do                         -- total all tokens
+    local ttype = TTYPES[i]
+    c = c + stat_c[ttype]; l = l + stat_l[ttype]
+    stat_a[ttype] = avg(stat_c[ttype], stat_l[ttype])
+  end
+  stat_c.TOTAL_ALL, stat_l.TOTAL_ALL = c, l
+  stat_a.TOTAL_ALL = avg(c, l)
+  return stat_a
+end
+
+
+----------------------------- Main tasks -----------------------------
+
+--- A simple token dumper, minimal translation of seminfo data.
+--
+-- @tparam string srcfl Path of the source file.
+local function dump_tokens(srcfl)
+  -- Load file and process source input into tokens.
+  local z = load_file(srcfl)
+  local toklist, seminfolist = llex.lex(z)
+
+  -- Display output.
+  for i = 1, #toklist do
+    local tok, seminfo = toklist[i], seminfolist[i]
+    if tok == "TK_OP" and byte(seminfo) < 32 then
+      seminfo = "("..byte(seminfo)..")"
+    elseif tok == "TK_EOL" then
+      seminfo = EOLTYPES[seminfo]
+    else
+      seminfo = "'"..seminfo.."'"
+    end
+    print(tok.." "..seminfo)
+  end--for
+end
+
+--- Dumps globalinfo and localinfo tables.
+--
+-- @tparam string srcfl Path of the source file.
+local function dump_parser(srcfl)
+  -- Load file and process source input into tokens,
+  local z = load_file(srcfl)
+  local toklist, seminfolist, toklnlist = llex.lex(z)
+
+  -- Do parser optimization here.
+  local xinfo = lparser.parse(toklist, seminfolist, toklnlist)
+  local globalinfo, localinfo = xinfo.globalinfo, xinfo.localinfo
+
+  -- Display output.
+  local hl = rep("-", 72)
+  print("*** Local/Global Variable Tracker Tables ***")
+  print(hl.."\n GLOBALS\n"..hl)
+  -- global tables have a list of xref numbers only
+  for i = 1, #globalinfo do
+    local obj = globalinfo[i]
+    local msg = "("..i..") '"..obj.name.."' -> "
+    local xref = obj.xref
+    for j = 1, #xref do msg = msg..xref[j].." " end
+    print(msg)
+  end
+  -- Local tables have xref numbers and a few other special
+  -- numbers that are specially named: decl (declaration xref),
+  -- act (activation xref), rem (removal xref).
+  print(hl.."\n LOCALS (decl=declared act=activated rem=removed)\n"..hl)
+  for i = 1, #localinfo do
+    local obj = localinfo[i]
+    local msg = "("..i..") '"..obj.name.."' decl:"..obj.decl..
+                " act:"..obj.act.." rem:"..obj.rem
+    if obj.is_special then
+      msg = msg.." is_special"
+    end
+    msg = msg.." -> "
+    local xref = obj.xref
+    for j = 1, #xref do msg = msg..xref[j].." " end
+    print(msg)
+  end
+  print(hl.."\n")
+end
+
+--- Reads source file(s) and reports some statistics.
+--
+-- @tparam string srcfl Path of the source file.
+local function read_only(srcfl)
+  -- Load file and process source input into tokens.
+  local z = load_file(srcfl)
+  local toklist, seminfolist = llex.lex(z)
+  print(MSG_TITLE)
+  print("Statistics for: "..srcfl.."\n")
+
+  -- Collect statistics.
+  stat_init()
+  for i = 1, #toklist do
+    local tok, seminfo = toklist[i], seminfolist[i]
+    stat_add(tok, seminfo)
+  end--for
+  local stat_a = stat_calc()
+
+  -- Display output.
+  local function figures(tt)
+    return stat_c[tt], stat_l[tt], stat_a[tt]
+  end
+  local tabf1, tabf2 = "%-16s%8s%8s%10s", "%-16s%8d%8d%10.2f"
+  local hl = rep("-", 42)
+  print(fmt(tabf1, "Lexical",  "Input", "Input", "Input"))
+  print(fmt(tabf1, "Elements", "Count", "Bytes", "Average"))
+  print(hl)
+  for i = 1, #TTYPES do
+    local ttype = TTYPES[i]
+    print(fmt(tabf2, ttype, figures(ttype)))
+    if ttype == "TK_EOS" then print(hl) end
+  end
+  print(hl)
+  print(fmt(tabf2, "Total Elements", figures("TOTAL_ALL")))
+  print(hl)
+  print(fmt(tabf2, "Total Tokens", figures("TOTAL_TOK")))
+  print(hl.."\n")
+end
+
+--- Processes source file(s), writes output and reports some statistics.
+--
+-- @tparam string srcfl Path of the source file.
+-- @tparam string destfl Path of the destination file where to write optimized source.
+local function process_file(srcfl, destfl)
+  -- handle quiet option
+  local function print(...)  --luacheck: ignore 431
+    if option.QUIET then return end
+    _G.print(...)
+  end
+  if plugin and plugin.init then        -- plugin init
+    option.EXIT = false
+    plugin.init(option, srcfl, destfl)
+    if option.EXIT then return end
+  end
+  print(MSG_TITLE)                      -- title message
+
+  -- Load file and process source input into tokens.
+  local z = load_file(srcfl)
+  if plugin and plugin.post_load then   -- plugin post-load
+    z = plugin.post_load(z) or z
+    if option.EXIT then return end
+  end
+  local toklist, seminfolist, toklnlist = llex.lex(z)
+  if plugin and plugin.post_lex then    -- plugin post-lex
+    plugin.post_lex(toklist, seminfolist, toklnlist)
+    if option.EXIT then return end
+  end
+
+  -- Collect 'before' statistics.
+  stat_init()
+  for i = 1, #toklist do
+    local tok, seminfo = toklist[i], seminfolist[i]
+    stat_add(tok, seminfo)
+  end--for
+  local stat1_a = stat_calc()
+  local stat1_c, stat1_l = stat_c, stat_l
+
+  -- Do parser optimization here.
+  optparser.print = print  -- hack
+  local xinfo = lparser.parse(toklist, seminfolist, toklnlist)
+  if plugin and plugin.post_parse then          -- plugin post-parse
+    plugin.post_parse(xinfo.globalinfo, xinfo.localinfo)
+    if option.EXIT then return end
+  end
+  optparser.optimize(option, toklist, seminfolist, xinfo)
+  if plugin and plugin.post_optparse then       -- plugin post-optparse
+    plugin.post_optparse()
+    if option.EXIT then return end
+  end
+
+  -- Do lexer optimization here, save output file.
+  local warn = optlex.warn  -- use this as a general warning lookup
+  optlex.print = print  -- hack
+  toklist, seminfolist, toklnlist
+    = optlex.optimize(option, toklist, seminfolist, toklnlist)
+  if plugin and plugin.post_optlex then         -- plugin post-optlex
+    plugin.post_optlex(toklist, seminfolist, toklnlist)
+    if option.EXIT then return end
+  end
+  local dat = concat(seminfolist)
+  -- Depending on options selected, embedded EOLs in long strings and
+  -- long comments may not have been translated to \n, tack a warning.
+  if find(dat, "\r\n", 1, 1) or
+     find(dat, "\n\r", 1, 1) then
+    warn.MIXEDEOL = true
+  end
+
+  -- Test source and binary chunk equivalence.
+  equiv.init(option, llex, warn)
+  equiv.source(z, dat)
+  if BIN_EQUIV_AVAIL then
+    equiv.binary(z, dat)
+  end
+  local smsg = "before and after lexer streams are NOT equivalent!"
+  local bmsg = "before and after binary chunks are NOT equivalent!"
+  -- for reporting, die if option was selected, else just warn
+  if warn.SRC_EQUIV then
+    if option["opt-srcequiv"] then die(smsg) end
+  else
+    print("*** SRCEQUIV: token streams are sort of equivalent")
+    if option["opt-locals"] then
+      print("(but no identifier comparisons since --opt-locals enabled)")
+    end
+    print()
+  end
+  if warn.BIN_EQUIV then
+    if option["opt-binequiv"] then die(bmsg) end
+  elseif BIN_EQUIV_AVAIL then
+    print("*** BINEQUIV: binary chunks are sort of equivalent")
+    print()
+  end
+
+  -- Save optimized source stream to output file.
+  save_file(destfl, dat)
+
+  -- Collect 'after' statistics.
+  stat_init()
+  for i = 1, #toklist do
+    local tok, seminfo = toklist[i], seminfolist[i]
+    stat_add(tok, seminfo)
+  end--for
+  local stat_a = stat_calc()
+
+  -- Display output.
+  print("Statistics for: "..srcfl.." -> "..destfl.."\n")
+  local function figures(tt)
+    return stat1_c[tt], stat1_l[tt], stat1_a[tt],
+           stat_c[tt],  stat_l[tt],  stat_a[tt]
+  end
+  local tabf1, tabf2 = "%-16s%8s%8s%10s%8s%8s%10s",
+                       "%-16s%8d%8d%10.2f%8d%8d%10.2f"
+  local hl = rep("-", 68)
+  print("*** lexer-based optimizations summary ***\n"..hl)
+  print(fmt(tabf1, "Lexical",
+            "Input", "Input", "Input",
+            "Output", "Output", "Output"))
+  print(fmt(tabf1, "Elements",
+            "Count", "Bytes", "Average",
+            "Count", "Bytes", "Average"))
+  print(hl)
+  for i = 1, #TTYPES do
+    local ttype = TTYPES[i]
+    print(fmt(tabf2, ttype, figures(ttype)))
+    if ttype == "TK_EOS" then print(hl) end
+  end
+  print(hl)
+  print(fmt(tabf2, "Total Elements", figures("TOTAL_ALL")))
+  print(hl)
+  print(fmt(tabf2, "Total Tokens", figures("TOTAL_TOK")))
+  print(hl)
+
+  -- Report warning flags from optimizing process.
+  if warn.LSTRING then
+    print("* WARNING: "..warn.LSTRING)
+  elseif warn.MIXEDEOL then
+    print("* WARNING: ".."output still contains some CRLF or LFCR line endings")
+  elseif warn.SRC_EQUIV then
+    print("* WARNING: "..smsg)
+  elseif warn.BIN_EQUIV then
+    print("* WARNING: "..bmsg)
+  end
+  print()
+end
+
+
+---------------------------- Main functions ---------------------------
+
+local arg = {...}  -- program arguments
+set_options(DEFAULT_CONFIG)     -- set to default options at beginning
+
+--- Does per-file handling, ship off to tasks.
+--
+-- @tparam {string,...} fspec List of source files.
+local function do_files(fspec)
+  for i = 1, #fspec do
+    local srcfl = fspec[i]
+    local destfl
+
+    -- Find and replace extension for filenames.
+    local extb, exte = find(srcfl, "%.[^%.%\\%/]*$")
+    local basename, extension = srcfl, ""
+    if extb and extb > 1 then
+      basename = sub(srcfl, 1, extb - 1)
+      extension = sub(srcfl, extb, exte)
+    end
+    destfl = basename..suffix..extension
+    if #fspec == 1 and option.OUTPUT_FILE then
+      destfl = option.OUTPUT_FILE
+    end
+    if srcfl == destfl then
+      die("output filename identical to input filename")
+    end
+
+    -- Perform requested operations.
+    if option.DUMP_LEXER then
+      dump_tokens(srcfl)
+    elseif option.DUMP_PARSER then
+      dump_parser(srcfl)
+    elseif option.READ_ONLY then
+      read_only(srcfl)
+    else
+      process_file(srcfl, destfl)
+    end
+  end--for
+end
+
+--- The main function.
+local function main()
+  local fspec = {}
+  local argn, i = #arg, 1
+  if argn == 0 then
+    option.HELP = true
+  end
+
+  -- Handle arguments.
+  while i <= argn do
+    local o, p = arg[i], arg[i + 1]
+    local dash = match(o, "^%-%-?")
+    if dash == "-" then                 -- single-dash options
+      if o == "-h" then
+        option.HELP = true; break
+      elseif o == "-v" then
+        option.VERSION = true; break
+      elseif o == "-s" then
+        if not p then die("-s option needs suffix specification") end
+        suffix = p
+        i = i + 1
+      elseif o == "-o" then
+        if not p then die("-o option needs a file name") end
+        option.OUTPUT_FILE = p
+        i = i + 1
+      elseif o == "-" then
+        break -- ignore rest of args
+      else
+        die("unrecognized option "..o)
+      end
+    elseif dash == "--" then            -- double-dash options
+      if o == "--help" then
+        option.HELP = true; break
+      elseif o == "--version" then
+        option.VERSION = true; break
+      elseif o == "--keep" then
+        if not p then die("--keep option needs a string to match for") end
+        option.KEEP = p
+        i = i + 1
+      elseif o == "--plugin" then
+        if not p then die("--plugin option needs a module name") end
+        if option.PLUGIN then die("only one plugin can be specified") end
+        option.PLUGIN = p
+        plugin = require(PLUGIN_SUFFIX..p)
+        i = i + 1
+      elseif o == "--quiet" then
+        option.QUIET = true
+      elseif o == "--read-only" then
+        option.READ_ONLY = true
+      elseif o == "--basic" then
+        set_options(BASIC_CONFIG)
+      elseif o == "--maximum" then
+        set_options(MAXIMUM_CONFIG)
+      elseif o == "--none" then
+        set_options(NONE_CONFIG)
+      elseif o == "--dump-lexer" then
+        option.DUMP_LEXER = true
+      elseif o == "--dump-parser" then
+        option.DUMP_PARSER = true
+      elseif o == "--details" then
+        option.DETAILS = true
+      elseif OPTION[o] then  -- lookup optimization options
+        set_options(o)
+      else
+        die("unrecognized option "..o)
+      end
+    else
+      fspec[#fspec + 1] = o             -- potential filename
+    end
+    i = i + 1
+  end--while
+  if option.HELP then
+    print(MSG_TITLE..MSG_USAGE); return true
+  elseif option.VERSION then
+    print(MSG_TITLE); return true
+  end
+  if option["opt-binequiv"] and not BIN_EQUIV_AVAIL then
+    die("--opt-binequiv is available only for PUC Lua 5.1!")
+  end
+  if #fspec > 0 then
+    if #fspec > 1 and option.OUTPUT_FILE then
+      die("with -o, only one source file can be specified")
+    end
+    do_files(fspec)
+    return true
+  else
+    die("nothing to do!")
+  end
+end
+
+-- entry point -> main() -> do_files()
+if not main() then
+  die("Please run with option -h or --help for usage information")
+end

tools/luasrcdiet/equiv.lua

@@ -0,0 +1,465 @@
+---------
+-- Source and binary equivalency comparisons
+--
+-- **Notes:**
+--
+-- * Intended as an extra safety check for mission-critical code,
+--   should give affirmative results if everything works.
+-- * Heavy on load() and string.dump(), which may be slowish,
+--   and may cause problems for cross-compiled applications.
+-- * Optional detailed information dump is mainly for debugging,
+--   reason being, if the two are not equivalent when they should be,
+--   then some form of optimization has failed.
+-- * source: IMPORTANT: TK_NAME not compared if opt-locals enabled.
+-- * binary: IMPORTANT: Some shortcuts are taken with int and size_t
+--   value reading -- if the functions break, then the binary chunk
+--   is very large indeed.
+-- * binary: There is a lack of diagnostic information when a compare
+--   fails; you can use ChunkSpy and compare using visual diff.
+----
+local byte = string.byte
+local dump = string.dump
+local load = loadstring or load  --luacheck: ignore 113
+local sub = string.sub
+
+local M = {}
+
+local is_realtoken = {          -- significant (grammar) tokens
+  TK_KEYWORD = true,
+  TK_NAME = true,
+  TK_NUMBER = true,
+  TK_STRING = true,
+  TK_LSTRING = true,
+  TK_OP = true,
+  TK_EOS = true,
+}
+
+local option, llex, warn
+
+
+--- The initialization function.
+--
+-- @tparam {[string]=bool,...} _option
+-- @tparam luasrcdiet.llex _llex
+-- @tparam table _warn
+function M.init(_option, _llex, _warn)
+  option = _option
+  llex = _llex
+  warn = _warn
+end
+
+--- Builds lists containing a 'normal' lexer stream.
+--
+-- @tparam string s The source code.
+-- @treturn table
+-- @treturn table
+local function build_stream(s)
+  local stok, sseminfo = llex.lex(s) -- source list (with whitespace elements)
+  local tok, seminfo   -- processed list (real elements only)
+    = {}, {}
+  for i = 1, #stok do
+    local t = stok[i]
+    if is_realtoken[t] then
+      tok[#tok + 1] = t
+      seminfo[#seminfo + 1] = sseminfo[i]
+    end
+  end--for
+  return tok, seminfo
+end
+
+-- Tests source (lexer stream) equivalence.
+--
+-- @tparam string z
+-- @tparam string dat
+function M.source(z, dat)
+
+  -- Returns a dumped string for seminfo compares.
+  local function dumpsem(s)
+    local sf = load("return "..s, "z")
+    if sf then
+      return dump(sf)
+    end
+  end
+
+  -- Marks and optionally reports non-equivalence.
+  local function bork(msg)
+    if option.DETAILS then print("SRCEQUIV: "..msg) end
+    warn.SRC_EQUIV = true
+  end
+
+  -- Get lexer streams for both source strings, compare.
+  local tok1, seminfo1 = build_stream(z)        -- original
+  local tok2, seminfo2 = build_stream(dat)      -- compressed
+
+  -- Compare shbang lines ignoring EOL.
+  local sh1 = z:match("^(#[^\r\n]*)")
+  local sh2 = dat:match("^(#[^\r\n]*)")
+  if sh1 or sh2 then
+    if not sh1 or not sh2 or sh1 ~= sh2 then
+      bork("shbang lines different")
+    end
+  end
+
+  -- Compare by simple count.
+  if #tok1 ~= #tok2 then
+    bork("count "..#tok1.." "..#tok2)
+    return
+  end
+
+  -- Compare each element the best we can.
+  for i = 1, #tok1 do
+    local t1, t2 = tok1[i], tok2[i]
+    local s1, s2 = seminfo1[i], seminfo2[i]
+    if t1 ~= t2 then  -- by type
+      bork("type ["..i.."] "..t1.." "..t2)
+      break
+    end
+    if t1 == "TK_KEYWORD" or t1 == "TK_NAME" or t1 == "TK_OP" then
+      if t1 == "TK_NAME" and option["opt-locals"] then
+        -- can't compare identifiers of locals that are optimized
+      elseif s1 ~= s2 then  -- by semantic info (simple)
+        bork("seminfo ["..i.."] "..t1.." "..s1.." "..s2)
+        break
+      end
+    elseif t1 == "TK_EOS" then
+      -- no seminfo to compare
+    else-- "TK_NUMBER" or "TK_STRING" or "TK_LSTRING"
+      -- compare 'binary' form, so dump a function
+      local s1b,s2b = dumpsem(s1), dumpsem(s2)
+      if not s1b or not s2b or s1b ~= s2b then
+        bork("seminfo ["..i.."] "..t1.." "..s1.." "..s2)
+        break
+      end
+    end
+  end--for
+
+  -- Successful comparison if end is reached with no borks.
+end
+
+--- Tests binary chunk equivalence (only for PUC Lua 5.1).
+--
+-- @tparam string z
+-- @tparam string dat
+function M.binary(z, dat)
+  local TNIL     = 0  --luacheck: ignore 211
+  local TBOOLEAN = 1
+  local TNUMBER  = 3
+  local TSTRING  = 4
+
+  -- sizes of data types
+  local endian
+  local sz_int
+  local sz_sizet
+  local sz_inst
+  local sz_number
+  local getint
+  local getsizet
+
+  -- Marks and optionally reports non-equivalence.
+  local function bork(msg)
+    if option.DETAILS then print("BINEQUIV: "..msg) end
+    warn.BIN_EQUIV = true
+  end
+
+  -- Checks if bytes exist.
+  local function ensure(c, sz)
+    if c.i + sz - 1 > c.len then return end
+    return true
+  end
+
+  -- Skips some bytes.
+  local function skip(c, sz)
+    if not sz then sz = 1 end
+    c.i = c.i + sz
+  end
+
+  -- Returns a byte value.
+  local function getbyte(c)
+    local i = c.i
+    if i > c.len then return end
+    local d = sub(c.dat, i, i)
+    c.i = i + 1
+    return byte(d)
+  end
+
+  -- Return an int value (little-endian).
+  local function getint_l(c)
+    local n, scale = 0, 1
+    if not ensure(c, sz_int) then return end
+    for _ = 1, sz_int do
+      n = n + scale * getbyte(c)
+      scale = scale * 256
+    end
+    return n
+  end
+
+  -- Returns an int value (big-endian).
+  local function getint_b(c)
+    local n = 0
+    if not ensure(c, sz_int) then return end
+    for _ = 1, sz_int do
+      n = n * 256 + getbyte(c)
+    end
+    return n
+  end
+
+  -- Returns a size_t value (little-endian).
+  local function getsizet_l(c)
+    local n, scale = 0, 1
+    if not ensure(c, sz_sizet) then return end
+    for _ = 1, sz_sizet do
+      n = n + scale * getbyte(c)
+      scale = scale * 256
+    end
+    return n
+  end
+
+  -- Returns a size_t value (big-endian).
+  local function getsizet_b(c)
+    local n = 0
+    if not ensure(c, sz_sizet) then return end
+    for _ = 1, sz_sizet do
+      n = n * 256 + getbyte(c)
+    end
+    return n
+  end
+
+  -- Returns a block (as a string).
+  local function getblock(c, sz)
+    local i = c.i
+    local j = i + sz - 1
+    if j > c.len then return end
+    local d = sub(c.dat, i, j)
+    c.i = i + sz
+    return d
+  end
+
+  -- Returns a string.
+  local function getstring(c)
+    local n = getsizet(c)
+    if not n then return end
+    if n == 0 then return "" end
+    return getblock(c, n)
+  end
+
+  -- Compares byte value.
+  local function goodbyte(c1, c2)
+    local b1, b2 = getbyte(c1), getbyte(c2)
+    if not b1 or not b2 or b1 ~= b2 then
+      return
+    end
+    return b1
+  end
+
+  -- Compares byte value.
+  local function badbyte(c1, c2)
+    local b = goodbyte(c1, c2)
+    if not b then return true end
+  end
+
+  -- Compares int value.
+  local function goodint(c1, c2)
+    local i1, i2 = getint(c1), getint(c2)
+    if not i1 or not i2 or i1 ~= i2 then
+      return
+    end
+    return i1
+  end
+
+  -- Recursively-called function to compare function prototypes.
+  local function getfunc(c1, c2)
+    -- source name (ignored)
+    if not getstring(c1) or not getstring(c2) then
+      bork("bad source name"); return
+    end
+    -- linedefined (ignored)
+    if not getint(c1) or not getint(c2) then
+      bork("bad linedefined"); return
+    end
+    -- lastlinedefined (ignored)
+    if not getint(c1) or not getint(c2) then
+      bork("bad lastlinedefined"); return
+    end
+    if not (ensure(c1, 4) and ensure(c2, 4)) then
+      bork("prototype header broken")
+    end
+    -- nups (compared)
+    if badbyte(c1, c2) then
+      bork("bad nups"); return
+    end
+    -- numparams (compared)
+    if badbyte(c1, c2) then
+      bork("bad numparams"); return
+    end
+    -- is_vararg (compared)
+    if badbyte(c1, c2) then
+      bork("bad is_vararg"); return
+    end
+    -- maxstacksize (compared)
+    if badbyte(c1, c2) then
+      bork("bad maxstacksize"); return
+    end
+    -- code (compared)
+    local ncode = goodint(c1, c2)
+    if not ncode then
+      bork("bad ncode"); return
+    end
+    local code1 = getblock(c1, ncode * sz_inst)
+    local code2 = getblock(c2, ncode * sz_inst)
+    if not code1 or not code2 or code1 ~= code2 then
+      bork("bad code block"); return
+    end
+    -- constants (compared)
+    local nconst = goodint(c1, c2)
+    if not nconst then
+      bork("bad nconst"); return
+    end
+    for _ = 1, nconst do
+      local ctype = goodbyte(c1, c2)
+      if not ctype then
+        bork("bad const type"); return
+      end
+      if ctype == TBOOLEAN then
+        if badbyte(c1, c2) then
+          bork("bad boolean value"); return
+        end
+      elseif ctype == TNUMBER then
+        local num1 = getblock(c1, sz_number)
+        local num2 = getblock(c2, sz_number)
+        if not num1 or not num2 or num1 ~= num2 then
+          bork("bad number value"); return
+        end
+      elseif ctype == TSTRING then
+        local str1 = getstring(c1)
+        local str2 = getstring(c2)
+        if not str1 or not str2 or str1 ~= str2 then
+          bork("bad string value"); return
+        end
+      end
+    end
+    -- prototypes (compared recursively)
+    local nproto = goodint(c1, c2)
+    if not nproto then
+      bork("bad nproto"); return
+    end
+    for _ = 1, nproto do
+      if not getfunc(c1, c2) then
+        bork("bad function prototype"); return
+      end
+    end
+    -- debug information (ignored)
+    -- lineinfo (ignored)
+    local sizelineinfo1 = getint(c1)
+    if not sizelineinfo1 then
+      bork("bad sizelineinfo1"); return
+    end
+    local sizelineinfo2 = getint(c2)
+    if not sizelineinfo2 then
+      bork("bad sizelineinfo2"); return
+    end
+    if not getblock(c1, sizelineinfo1 * sz_int) then
+      bork("bad lineinfo1"); return
+    end
+    if not getblock(c2, sizelineinfo2 * sz_int) then
+      bork("bad lineinfo2"); return
+    end
+    -- locvars (ignored)
+    local sizelocvars1 = getint(c1)
+    if not sizelocvars1 then
+      bork("bad sizelocvars1"); return
+    end
+    local sizelocvars2 = getint(c2)
+    if not sizelocvars2 then
+      bork("bad sizelocvars2"); return
+    end
+    for _ = 1, sizelocvars1 do
+      if not getstring(c1) or not getint(c1) or not getint(c1) then
+        bork("bad locvars1"); return
+      end
+    end
+    for _ = 1, sizelocvars2 do
+      if not getstring(c2) or not getint(c2) or not getint(c2) then
+        bork("bad locvars2"); return
+      end
+    end
+    -- upvalues (ignored)
+    local sizeupvalues1 = getint(c1)
+    if not sizeupvalues1 then
+      bork("bad sizeupvalues1"); return
+    end
+    local sizeupvalues2 = getint(c2)
+    if not sizeupvalues2 then
+      bork("bad sizeupvalues2"); return
+    end
+    for _ = 1, sizeupvalues1 do
+      if not getstring(c1) then bork("bad upvalues1"); return end
+    end
+    for _ = 1, sizeupvalues2 do
+      if not getstring(c2) then bork("bad upvalues2"); return end
+    end
+    return true
+  end
+
+  -- Removes shbang line so that load runs.
+  local function zap_shbang(s)
+    local shbang = s:match("^(#[^\r\n]*\r?\n?)")
+    if shbang then                      -- cut out shbang
+      s = sub(s, #shbang + 1)
+    end
+    return s
+  end
+
+  -- Attempt to compile, then dump to get binary chunk string.
+  local cz = load(zap_shbang(z), "z")
+  if not cz then
+    bork("failed to compile original sources for binary chunk comparison")
+    return
+  end
+
+  local cdat = load(zap_shbang(dat), "z")
+  if not cdat then
+    bork("failed to compile compressed result for binary chunk comparison")
+  end
+
+  -- if load() works, dump assuming string.dump() is error-free
+  local c1 = { i = 1, dat = dump(cz) }
+  c1.len = #c1.dat
+
+  local c2 = { i = 1, dat = dump(cdat) }
+  c2.len = #c2.dat
+
+  -- Parse binary chunks to verify equivalence.
+  -- * For headers, handle sizes to allow a degree of flexibility.
+  -- * Assume a valid binary chunk is generated, since it was not
+  --   generated via external means.
+  if not (ensure(c1, 12) and ensure(c2, 12)) then
+    bork("header broken")
+  end
+  skip(c1, 6)                   -- skip signature(4), version, format
+  endian    = getbyte(c1)       -- 1 = little endian
+  sz_int    = getbyte(c1)       -- get data type sizes
+  sz_sizet  = getbyte(c1)
+  sz_inst   = getbyte(c1)
+  sz_number = getbyte(c1)
+  skip(c1)                      -- skip integral flag
+  skip(c2, 12)                  -- skip other header (assume similar)
+
+  if endian == 1 then           -- set for endian sensitive data we need
+    getint   = getint_l
+    getsizet = getsizet_l
+  else
+    getint   = getint_b
+    getsizet = getsizet_b
+  end
+  getfunc(c1, c2)               -- get prototype at root
+
+  if c1.i ~= c1.len + 1 then
+    bork("inconsistent binary chunk1"); return
+  elseif c2.i ~= c2.len + 1 then
+    bork("inconsistent binary chunk2"); return
+  end
+
+  -- Successful comparison if end is reached with no borks.
+end
+
+return M

tools/luasrcdiet/fs.lua

@@ -0,0 +1,74 @@
+---------
+-- Utility functions for operations on a file system.
+--
+-- **Note: This module is not part of public API!**
+----
+local fmt = string.format
+local open = io.open
+
+local UTF8_BOM = '\239\187\191'
+
+local function normalize_io_error (name, err)
+  if err:sub(1, #name + 2) == name..': ' then
+    err = err:sub(#name + 3)
+  end
+  return err
+end
+
+local M = {}
+
+--- Reads the specified file and returns its content as string.
+--
+-- @tparam string filename Path of the file to read.
+-- @tparam string mode The mode in which to open the file, see @{io.open} (default: "r").
+-- @treturn[1] string A content of the file.
+-- @treturn[2] nil
+-- @treturn[2] string An error message.
+function M.read_file (filename, mode)
+  local handler, err = open(filename, mode or 'r')
+  if not handler then
+    return nil, fmt('Could not open %s for reading: %s',
+                    filename, normalize_io_error(filename, err))
+  end
+
+  local content, err = handler:read('*a')  --luacheck: ignore 411
+  if not content then
+    return nil, fmt('Could not read %s: %s', filename, normalize_io_error(filename, err))
+  end
+
+  handler:close()
+
+  if content:sub(1, #UTF8_BOM) == UTF8_BOM then
+    content = content:sub(#UTF8_BOM + 1)
+  end
+
+  return content
+end
+
+--- Writes the given data to the specified file.
+--
+-- @tparam string filename Path of the file to write.
+-- @tparam string data The data to write.
+-- @tparam ?string mode The mode in which to open the file, see @{io.open} (default: "w").
+-- @treturn[1] true
+-- @treturn[2] nil
+-- @treturn[2] string An error message.
+function M.write_file (filename, data, mode)
+  local handler, err = open(filename, mode or 'w')
+  if not handler then
+    return nil, fmt('Could not open %s for writing: %s',
+                    filename, normalize_io_error(filename, err))
+  end
+
+  local _, err = handler:write(data)  --luacheck: ignore 411
+  if err then
+    return nil, fmt('Could not write %s: %s', filename, normalize_io_error(filename, err))
+  end
+
+  handler:flush()
+  handler:close()
+
+  return true
+end
+
+return M

tools/luasrcdiet/init.lua

@@ -0,0 +1,117 @@
+---------
+-- LuaSrcDiet API
+----
+local equiv = require 'luasrcdiet.equiv'
+local llex = require 'luasrcdiet.llex'
+local lparser = require 'luasrcdiet.lparser'
+local optlex = require 'luasrcdiet.optlex'
+local optparser = require 'luasrcdiet.optparser'
+local utils = require 'luasrcdiet.utils'
+
+local concat = table.concat
+local merge = utils.merge
+
+local _  -- placeholder
+
+
+local function noop ()
+  return
+end
+
+local function opts_to_legacy (opts)
+  local res = {}
+  for key, val in pairs(opts) do
+    res['opt-'..key] = val
+  end
+  return res
+end
+
+
+local M = {}
+
+--- The module's name.
+M._NAME = 'luasrcdiet'
+
+--- The module's version number.
+M._VERSION = '1.0.0'
+
+--- The module's homepage.
+M._HOMEPAGE = 'https://github.com/jirutka/luasrcdiet'
+
+--- All optimizations disabled.
+M.NONE_OPTS = {
+  binequiv = false,
+  comments = false,
+  emptylines = false,
+  entropy = false,
+  eols = false,
+  experimental = false,
+  locals = false,
+  numbers = false,
+  srcequiv = false,
+  strings = false,
+  whitespace = false,
+}
+
+--- Basic optimizations enabled.
+-- @table BASIC_OPTS
+M.BASIC_OPTS = merge(M.NONE_OPTS, {
+  comments = true,
+  emptylines = true,
+  srcequiv = true,
+  whitespace = true,
+})
+
+--- Defaults.
+-- @table DEFAULT_OPTS
+M.DEFAULT_OPTS = merge(M.BASIC_OPTS, {
+  locals = true,
+  numbers = true,
+})
+
+--- Maximum optimizations enabled (all except experimental).
+-- @table MAXIMUM_OPTS
+M.MAXIMUM_OPTS = merge(M.DEFAULT_OPTS, {
+  entropy = true,
+  eols = true,
+  strings = true,
+})
+
+--- Optimizes the given Lua source code.
+--
+-- @tparam ?{[string]=bool,...} opts Optimizations to do (default is @{DEFAULT_OPTS}).
+-- @tparam string source The Lua source code to optimize.
+-- @treturn string Optimized source.
+-- @raise if the source is malformed, source equivalence test failed, or some
+--   other error occured.
+function M.optimize (opts, source)
+  assert(source and type(source) == 'string',
+         'bad argument #2: expected string, got a '..type(source))
+
+  opts = opts and merge(M.NONE_OPTS, opts) or M.DEFAULT_OPTS
+  local legacy_opts = opts_to_legacy(opts)
+
+  local toklist, seminfolist, toklnlist = llex.lex(source)
+  local xinfo = lparser.parse(toklist, seminfolist, toklnlist)
+
+  optparser.print = noop
+  optparser.optimize(legacy_opts, toklist, seminfolist, xinfo)
+
+  local warn = optlex.warn  -- use this as a general warning lookup
+  optlex.print = noop
+  _, seminfolist = optlex.optimize(legacy_opts, toklist, seminfolist, toklnlist)
+  local optim_source = concat(seminfolist)
+
+  if opts.srcequiv and not opts.experimental then
+    equiv.init(legacy_opts, llex, warn)
+    equiv.source(source, optim_source)
+
+    if warn.SRC_EQUIV then
+      error('Source equivalence test failed!')
+    end
+  end
+
+  return optim_source
+end
+
+return M

tools/luasrcdiet/llex.lua

@@ -0,0 +1,350 @@
+---------
+-- Lua 5.1+ lexical analyzer written in Lua.
+--
+-- This file is part of LuaSrcDiet, based on Yueliang material.
+--
+-- **Notes:**
+--
+-- * This is a version of the native 5.1.x lexer from Yueliang 0.4.0,
+--   with significant modifications to handle LuaSrcDiet's needs:
+--   (1) llex.error is an optional error function handler,
+--   (2) seminfo for strings include their delimiters and no
+--       translation operations are performed on them.
+-- * ADDED shbang handling has been added to support executable scripts.
+-- * NO localized decimal point replacement magic.
+-- * NO limit to number of lines.
+-- * NO support for compatible long strings (LUA\_COMPAT_LSTR).
+-- * Added goto keyword and double-colon operator (Lua 5.2+).
+----
+local find = string.find
+local fmt = string.format
+local match = string.match
+local sub = string.sub
+local tonumber = tonumber
+
+local M = {}
+
+local kw = {}
+for v in ([[
+and break do else elseif end false for function goto if in
+local nil not or repeat return then true until while]]):gmatch("%S+") do
+  kw[v] = true
+end
+
+local z,                -- source stream
+      sourceid,         -- name of source
+      I,                -- position of lexer
+      buff,             -- buffer for strings
+      ln,               -- line number
+      tok,              -- lexed token list
+      seminfo,          -- lexed semantic information list
+      tokln             -- line numbers for messages
+
+
+--- Adds information to token listing.
+--
+-- @tparam string token
+-- @tparam string info
+local function addtoken(token, info)
+  local i = #tok + 1
+  tok[i] = token
+  seminfo[i] = info
+  tokln[i] = ln
+end
+
+--- Handles line number incrementation and end-of-line characters.
+--
+-- @tparam int i Position of lexer in the source stream.
+-- @tparam bool is_tok
+-- @treturn int
+local function inclinenumber(i, is_tok)
+  local old = sub(z, i, i)
+  i = i + 1  -- skip '\n' or '\r'
+  local c = sub(z, i, i)
+  if (c == "\n" or c == "\r") and (c ~= old) then
+    i = i + 1  -- skip '\n\r' or '\r\n'
+    old = old..c
+  end
+  if is_tok then addtoken("TK_EOL", old) end
+  ln = ln + 1
+  I = i
+  return i
+end
+
+--- Returns a chunk name or id, no truncation for long names.
+--
+-- @treturn string
+local function chunkid()
+  if sourceid and match(sourceid, "^[=@]") then
+    return sub(sourceid, 2)  -- remove first char
+  end
+  return "[string]"
+end
+
+--- Formats error message and throws error.
+--
+-- A simplified version, does not report what token was responsible.
+--
+-- @tparam string s
+-- @tparam int line The line number.
+-- @raise
+local function errorline(s, line)
+  local e = M.error or error
+  e(fmt("%s:%d: %s", chunkid(), line or ln, s))
+end
+
+--- Counts separators (`="` in a long string delimiter.
+--
+-- @tparam int i Position of lexer in the source stream.
+-- @treturn int
+local function skip_sep(i)
+  local s = sub(z, i, i)
+  i = i + 1
+  local count = #match(z, "=*", i)
+  i = i + count
+  I = i
+  return (sub(z, i, i) == s) and count or (-count) - 1
+end
+
+--- Reads a long string or long comment.
+--
+-- @tparam bool is_str
+-- @tparam string sep
+-- @treturn string
+-- @raise if unfinished long string or comment.
+local function read_long_string(is_str, sep)
+  local i = I + 1  -- skip 2nd '['
+  local c = sub(z, i, i)
+  if c == "\r" or c == "\n" then  -- string starts with a newline?
+    i = inclinenumber(i)  -- skip it
+  end
+  while true do
+    local p, _, r = find(z, "([\r\n%]])", i) -- (long range match)
+    if not p then
+      errorline(is_str and "unfinished long string" or
+                "unfinished long comment")
+    end
+    i = p
+    if r == "]" then                    -- delimiter test
+      if skip_sep(i) == sep then
+        buff = sub(z, buff, I)
+        I = I + 1  -- skip 2nd ']'
+        return buff
+      end
+      i = I
+    else                                -- newline
+      buff = buff.."\n"
+      i = inclinenumber(i)
+    end
+  end--while
+end
+
+--- Reads a string.
+--
+-- @tparam string del The delimiter.
+-- @treturn string
+-- @raise if unfinished string or too large escape sequence.
+local function read_string(del)
+  local i = I
+  while true do
+    local p, _, r = find(z, "([\n\r\\\"\'])", i) -- (long range match)
+    if p then
+      if r == "\n" or r == "\r" then
+        errorline("unfinished string")
+      end
+      i = p
+      if r == "\\" then                         -- handle escapes
+        i = i + 1
+        r = sub(z, i, i)
+        if r == "" then break end -- (EOZ error)
+        p = find("abfnrtv\n\r", r, 1, true)
+
+        if p then                               -- special escapes
+          if p > 7 then
+            i = inclinenumber(i)
+          else
+            i = i + 1
+          end
+
+        elseif find(r, "%D") then               -- other non-digits
+          i = i + 1
+
+        else                                    -- \xxx sequence
+          local _, q, s = find(z, "^(%d%d?%d?)", i)
+          i = q + 1
+          if s + 1 > 256 then -- UCHAR_MAX
+            errorline("escape sequence too large")
+          end
+
+        end--if p
+      else
+        i = i + 1
+        if r == del then                        -- ending delimiter
+          I = i
+          return sub(z, buff, i - 1)            -- return string
+        end
+      end--if r
+    else
+      break -- (error)
+    end--if p
+  end--while
+  errorline("unfinished string")
+end
+
+
+--- Initializes lexer for given source _z and source name _sourceid.
+--
+-- @tparam string _z The source code.
+-- @tparam string _sourceid Name of the source.
+local function init(_z, _sourceid)
+  z = _z                        -- source
+  sourceid = _sourceid          -- name of source
+  I = 1                         -- lexer's position in source
+  ln = 1                        -- line number
+  tok = {}                      -- lexed token list*
+  seminfo = {}                  -- lexed semantic information list*
+  tokln = {}                    -- line numbers for messages*
+
+  -- Initial processing (shbang handling).
+  local p, _, q, r = find(z, "^(#[^\r\n]*)(\r?\n?)")
+  if p then                             -- skip first line
+    I = I + #q
+    addtoken("TK_COMMENT", q)
+    if #r > 0 then inclinenumber(I, true) end
+  end
+end
+
+--- Runs lexer on the given source code.
+--
+-- @tparam string source The Lua source to scan.
+-- @tparam ?string source_name Name of the source (optional).
+-- @treturn {string,...} A list of lexed tokens.
+-- @treturn {string,...} A list of semantic information (lexed strings).
+-- @treturn {int,...} A list of line numbers.
+function M.lex(source, source_name)
+  init(source, source_name)
+
+  while true do--outer
+    local i = I
+    -- inner loop allows break to be used to nicely section tests
+    while true do --luacheck: ignore 512
+
+      local p, _, r = find(z, "^([_%a][_%w]*)", i)
+      if p then
+        I = i + #r
+        if kw[r] then
+          addtoken("TK_KEYWORD", r)             -- reserved word (keyword)
+        else
+          addtoken("TK_NAME", r)                -- identifier
+        end
+        break -- (continue)
+      end
+
+      local p, _, r = find(z, "^(%.?)%d", i)
+      if p then                                 -- numeral
+        if r == "." then i = i + 1 end
+        local _, q, r = find(z, "^%d*[%.%d]*([eE]?)", i)  --luacheck: ignore 421
+        i = q + 1
+        if #r == 1 then                         -- optional exponent
+          if match(z, "^[%+%-]", i) then        -- optional sign
+            i = i + 1
+          end
+        end
+        local _, q = find(z, "^[_%w]*", i)
+        I = q + 1
+        local v = sub(z, p, q)                  -- string equivalent
+        if not tonumber(v) then            -- handles hex test also
+          errorline("malformed number")
+        end
+        addtoken("TK_NUMBER", v)
+        break -- (continue)
+      end
+
+      local p, q, r, t = find(z, "^((%s)[ \t\v\f]*)", i)
+      if p then
+        if t == "\n" or t == "\r" then          -- newline
+          inclinenumber(i, true)
+        else
+          I = q + 1                             -- whitespace
+          addtoken("TK_SPACE", r)
+        end
+        break -- (continue)
+      end
+
+      local _, q = find(z, "^::", i)
+      if q then
+        I = q + 1
+        addtoken("TK_OP", "::")
+        break -- (continue)
+      end
+
+      local r = match(z, "^%p", i)
+      if r then
+        buff = i
+        local p = find("-[\"\'.=<>~", r, 1, true)  --luacheck: ignore 421
+        if p then
+
+          -- two-level if block for punctuation/symbols
+          if p <= 2 then
+            if p == 1 then                      -- minus
+              local c = match(z, "^%-%-(%[?)", i)
+              if c then
+                i = i + 2
+                local sep = -1
+                if c == "[" then
+                  sep = skip_sep(i)
+                end
+                if sep >= 0 then                -- long comment
+                  addtoken("TK_LCOMMENT", read_long_string(false, sep))
+                else                            -- short comment
+                  I = find(z, "[\n\r]", i) or (#z + 1)
+                  addtoken("TK_COMMENT", sub(z, buff, I - 1))
+                end
+                break -- (continue)
+              end
+              -- (fall through for "-")
+            else                                -- [ or long string
+              local sep = skip_sep(i)
+              if sep >= 0 then
+                addtoken("TK_LSTRING", read_long_string(true, sep))
+              elseif sep == -1 then
+                addtoken("TK_OP", "[")
+              else
+                errorline("invalid long string delimiter")
+              end
+              break -- (continue)
+            end
+
+          elseif p <= 5 then
+            if p < 5 then                       -- strings
+              I = i + 1
+              addtoken("TK_STRING", read_string(r))
+              break -- (continue)
+            end
+            r = match(z, "^%.%.?%.?", i)        -- .|..|... dots
+            -- (fall through)
+
+          else                                  -- relational
+            r = match(z, "^%p=?", i)
+            -- (fall through)
+          end
+        end
+        I = i + #r
+        addtoken("TK_OP", r)  -- for other symbols, fall through
+        break -- (continue)
+      end
+
+      local r = sub(z, i, i)
+      if r ~= "" then
+        I = i + 1
+        addtoken("TK_OP", r)                    -- other single-char tokens
+        break
+      end
+      addtoken("TK_EOS", "")                    -- end of stream,
+      return tok, seminfo, tokln                -- exit here
+
+    end--while inner
+  end--while outer
+end
+
+return M

tools/luasrcdiet/optlex.lua

@@ -0,0 +1,852 @@
+---------
+-- This module does lexer-based optimizations.
+--
+-- **Notes:**
+--
+-- * TODO: General string delimiter conversion optimizer.
+-- * TODO: (numbers) warn if overly significant digit.
+----
+local char = string.char
+local find = string.find
+local match = string.match
+local rep = string.rep
+local sub = string.sub
+local tonumber = tonumber
+local tostring = tostring
+
+local print                     -- set in optimize()
+
+local M = {}
+
+-- error function, can override by setting own function into module
+M.error = error
+
+M.warn = {}                       -- table for warning flags
+
+local stoks, sinfos, stoklns    -- source lists
+
+local is_realtoken = {          -- significant (grammar) tokens
+  TK_KEYWORD = true,
+  TK_NAME = true,
+  TK_NUMBER = true,
+  TK_STRING = true,
+  TK_LSTRING = true,
+  TK_OP = true,
+  TK_EOS = true,
+}
+local is_faketoken = {          -- whitespace (non-grammar) tokens
+  TK_COMMENT = true,
+  TK_LCOMMENT = true,
+  TK_EOL = true,
+  TK_SPACE = true,
+}
+
+local opt_details               -- for extra information
+
+--- Returns true if current token is at the start of a line.
+--
+-- It skips over deleted tokens via recursion.
+--
+-- @tparam int i
+-- @treturn bool
+local function atlinestart(i)
+  local tok = stoks[i - 1]
+  if i <= 1 or tok == "TK_EOL" then
+    return true
+  elseif tok == "" then
+    return atlinestart(i - 1)
+  end
+  return false
+end
+
+--- Returns true if current token is at the end of a line.
+--
+-- It skips over deleted tokens via recursion.
+--
+-- @tparam int i
+-- @treturn bool
+local function atlineend(i)
+  local tok = stoks[i + 1]
+  if i >= #stoks or tok == "TK_EOL" or tok == "TK_EOS" then
+    return true
+  elseif tok == "" then
+    return atlineend(i + 1)
+  end
+  return false
+end
+
+--- Counts comment EOLs inside a long comment.
+--
+-- In order to keep line numbering, EOLs need to be reinserted.
+--
+-- @tparam string lcomment
+-- @treturn int
+local function commenteols(lcomment)
+  local sep = #match(lcomment, "^%-%-%[=*%[")
+  local z = sub(lcomment, sep + 1, -(sep - 1))  -- remove delims
+  local i, c = 1, 0
+  while true do
+    local p, _, r, s = find(z, "([\r\n])([\r\n]?)", i)
+    if not p then break end     -- if no matches, done
+    i = p + 1
+    c = c + 1
+    if #s > 0 and r ~= s then   -- skip CRLF or LFCR
+      i = i + 1
+    end
+  end
+  return c
+end
+
+--- Compares two tokens (i, j) and returns the whitespace required.
+--
+-- See documentation for a reference table of interactions.
+--
+-- Only two grammar/real tokens are being considered:
+--
+-- * if `""`, no separation is needed,
+-- * if `" "`, then at least one whitespace (or EOL) is required.
+--
+-- Note: This doesn't work at the start or the end or for EOS!
+--
+-- @tparam int i
+-- @tparam int j
+-- @treturn string
+local function checkpair(i, j)
+  local t1, t2 = stoks[i], stoks[j]
+
+  if t1 == "TK_STRING" or t1 == "TK_LSTRING" or
+     t2 == "TK_STRING" or t2 == "TK_LSTRING" then
+    return ""
+
+  elseif t1 == "TK_OP" or t2 == "TK_OP" then
+    if (t1 == "TK_OP" and (t2 == "TK_KEYWORD" or t2 == "TK_NAME")) or
+       (t2 == "TK_OP" and (t1 == "TK_KEYWORD" or t1 == "TK_NAME")) then
+      return ""
+    end
+    if t1 == "TK_OP" and t2 == "TK_OP" then
+      -- for TK_OP/TK_OP pairs, see notes in technotes.txt
+      local op, op2 = sinfos[i], sinfos[j]
+      if (match(op, "^%.%.?$") and match(op2, "^%.")) or
+         (match(op, "^[~=<>]$") and op2 == "=") or
+         (op == "[" and (op2 == "[" or op2 == "=")) then
+        return " "
+      end
+      return ""
+    end
+    -- "TK_OP" + "TK_NUMBER" case
+    local op = sinfos[i]
+    if t2 == "TK_OP" then op = sinfos[j] end
+    if match(op, "^%.%.?%.?$") then
+      return " "
+    end
+    return ""
+
+  else-- "TK_KEYWORD" | "TK_NAME" | "TK_NUMBER" then
+    return " "
+
+  end
+end
+
+--- Repack tokens, removing deletions caused by optimization process.
+local function repack_tokens()
+  local dtoks, dinfos, dtoklns = {}, {}, {}
+  local j = 1
+  for i = 1, #stoks do
+    local tok = stoks[i]
+    if tok ~= "" then
+      dtoks[j], dinfos[j], dtoklns[j] = tok, sinfos[i], stoklns[i]
+      j = j + 1
+    end
+  end
+  stoks, sinfos, stoklns = dtoks, dinfos, dtoklns
+end
+
+--- Does number optimization.
+--
+-- Optimization using string formatting functions is one way of doing this,
+-- but here, we consider all cases and handle them separately (possibly an
+-- idiotic approach...).
+--
+-- Scientific notation being generated is not in canonical form, this may or
+-- may not be a bad thing.
+--
+-- Note: Intermediate portions need to fit into a normal number range.
+--
+-- Optimizations can be divided based on number patterns:
+--
+-- * hexadecimal:
+--   (1) no need to remove leading zeros, just skip to (2)
+--   (2) convert to integer if size equal or smaller
+--       * change if equal size -> lose the 'x' to reduce entropy
+--   (3) number is then processed as an integer
+--   (4) note: does not make 0[xX] consistent
+-- * integer:
+--   (1) reduce useless fractional part, if present, e.g. 123.000 -> 123.
+--   (2) remove leading zeros, e.g. 000123
+-- * float:
+--   (1) split into digits dot digits
+--   (2) if no integer portion, take as zero (can omit later)
+--   (3) handle degenerate .000 case, after which the fractional part
+--       must be non-zero (if zero, it's matched as float .0)
+--   (4) remove trailing zeros for fractional portion
+--   (5) p.q where p > 0 and q > 0 cannot be shortened any more
+--   (6) otherwise p == 0 and the form is .q, e.g. .000123
+--   (7) if scientific shorter, convert, e.g. .000123 -> 123e-6
+-- * scientific:
+--   (1) split into (digits dot digits) [eE] ([+-] digits)
+--   (2) if significand is zero, just use .0
+--   (3) remove leading zeros for significand
+--   (4) shift out trailing zeros for significand
+--   (5) examine exponent and determine which format is best:
+--       number with fraction, or scientific
+--
+-- Note: Number with fraction and scientific number is never converted
+-- to integer, because Lua 5.3 distinguishes between integers and floats.
+--
+--
+-- @tparam int i
+local function do_number(i)
+  local before = sinfos[i]      -- 'before'
+  local z = before              -- working representation
+  local y                       -- 'after', if better
+  --------------------------------------------------------------------
+  if match(z, "^0[xX]") then            -- hexadecimal number
+    local v = tostring(tonumber(z))
+    if #v <= #z then
+      z = v  -- change to integer, AND continue
+    else
+      return  -- no change; stick to hex
+    end
+  end
+
+  if match(z, "^%d+$") then        -- integer
+    if tonumber(z) > 0 then
+      y = match(z, "^0*([1-9]%d*)$")  -- remove leading zeros
+    else
+      y = "0"  -- basic zero
+    end
+
+  elseif not match(z, "[eE]") then      -- float
+    local p, q = match(z, "^(%d*)%.(%d*)$")  -- split
+    if p == "" then p = 0 end  -- int part zero
+    if q == "" then q = "0" end  -- fraction part zero
+    if tonumber(q) == 0 and p == 0 then
+      y = ".0"  -- degenerate .000 to .0
+    else
+      -- now, q > 0 holds and p is a number
+      local zeros_cnt = #match(q, "0*$")  -- remove trailing zeros
+      if zeros_cnt > 0 then
+        q = sub(q, 1, #q - zeros_cnt)
+      end
+      -- if p > 0, nothing else we can do to simplify p.q case
+      if tonumber(p) > 0 then
+        y = p.."."..q
+      else
+        y = "."..q  -- tentative, e.g. .000123
+        local v = #match(q, "^0*")  -- # leading spaces
+        local w = #q - v            -- # significant digits
+        local nv = tostring(#q)
+        -- e.g. compare 123e-6 versus .000123
+        if w + 2 + #nv < 1 + #q then
+          y = sub(q, -w).."e-"..nv
+        end
+      end
+    end
+
+  else                                  -- scientific number
+    local sig, ex = match(z, "^([^eE]+)[eE]([%+%-]?%d+)$")
+    ex = tonumber(ex)
+    -- if got ".", shift out fractional portion of significand
+    local p, q = match(sig, "^(%d*)%.(%d*)$")
+    if p then
+      ex = ex - #q
+      sig = p..q
+    end
+    if tonumber(sig) == 0 then
+      y = ".0"  -- basic float zero
+    else
+      local v = #match(sig, "^0*")  -- remove leading zeros
+      sig = sub(sig, v + 1)
+      v = #match(sig, "0*$") -- shift out trailing zeros
+      if v > 0 then
+        sig = sub(sig, 1, #sig - v)
+        ex = ex + v
+      end
+      -- examine exponent and determine which format is best
+      local nex = tostring(ex)
+      if ex >= 0 and (ex <= 1 + #nex) then  -- a float
+        y = sig..rep("0", ex).."."
+      elseif ex < 0 and (ex >= -#sig) then  -- fraction, e.g. .123
+        v = #sig + ex
+        y = sub(sig, 1, v).."."..sub(sig, v + 1)
+      elseif ex < 0 and (#nex >= -ex - #sig) then
+        -- e.g. compare 1234e-5 versus .01234
+        -- gives: #sig + 1 + #nex >= 1 + (-ex - #sig) + #sig
+        --     -> #nex >= -ex - #sig
+        v = -ex - #sig
+        y = "."..rep("0", v)..sig
+      else  -- non-canonical scientific representation
+        y = sig.."e"..ex
+      end
+    end--if sig
+  end
+
+  if y and y ~= sinfos[i] then
+    if opt_details then
+      print("<number> (line "..stoklns[i]..") "..sinfos[i].." -> "..y)
+      opt_details = opt_details + 1
+    end
+    sinfos[i] = y
+  end
+end
+
+--- Does string optimization.
+--
+-- Note: It works on well-formed strings only!
+--
+-- Optimizations on characters can be summarized as follows:
+--
+--     \a\b\f\n\r\t\v -- no change
+--     \\             -- no change
+--     \"\'           -- depends on delim, other can remove \
+--     \[\]           -- remove \
+--     \<char>        -- general escape, remove \  (Lua 5.1 only)
+--     \<eol>         -- normalize the EOL only
+--     \ddd           -- if \a\b\f\n\r\t\v, change to latter
+--                       if other < ascii 32, keep ddd but zap leading zeros
+--                                            but cannot have following digits
+--                       if >= ascii 32, translate it into the literal, then also
+--                                       do escapes for \\,\",\' cases
+--     <other>        -- no change
+--
+-- Switch delimiters if string becomes shorter.
+--
+-- @tparam int I
+local function do_string(I)
+  local info = sinfos[I]
+  local delim = sub(info, 1, 1)                 -- delimiter used
+  local ndelim = (delim == "'") and '"' or "'"  -- opposite " <-> '
+  local z = sub(info, 2, -2)                    -- actual string
+  local i = 1
+  local c_delim, c_ndelim = 0, 0                -- "/' counts
+
+  while i <= #z do
+    local c = sub(z, i, i)
+
+    if c == "\\" then                   -- escaped stuff
+      local j = i + 1
+      local d = sub(z, j, j)
+      local p = find("abfnrtv\\\n\r\"\'0123456789", d, 1, true)
+
+      if not p then                     -- \<char> -- remove \  (Lua 5.1 only)
+        z = sub(z, 1, i - 1)..sub(z, j)
+        i = i + 1
+
+      elseif p <= 8 then                -- \a\b\f\n\r\t\v\\
+        i = i + 2                       -- no change
+
+      elseif p <= 10 then               -- \<eol> -- normalize EOL
+        local eol = sub(z, j, j + 1)
+        if eol == "\r\n" or eol == "\n\r" then
+          z = sub(z, 1, i).."\n"..sub(z, j + 2)
+        elseif p == 10 then  -- \r case
+          z = sub(z, 1, i).."\n"..sub(z, j + 1)
+        end
+        i = i + 2
+
+      elseif p <= 12 then               -- \"\' -- remove \ for ndelim
+        if d == delim then
+          c_delim = c_delim + 1
+          i = i + 2
+        else
+          c_ndelim = c_ndelim + 1
+          z = sub(z, 1, i - 1)..sub(z, j)
+          i = i + 1
+        end
+
+      else                              -- \ddd -- various steps
+        local s = match(z, "^(%d%d?%d?)", j)
+        j = i + 1 + #s                  -- skip to location
+        local cv = tonumber(s)
+        local cc = char(cv)
+        p = find("\a\b\f\n\r\t\v", cc, 1, true)
+        if p then                       -- special escapes
+          s = "\\"..sub("abfnrtv", p, p)
+        elseif cv < 32 then             -- normalized \ddd
+          if match(sub(z, j, j), "%d") then
+            -- if a digit follows, \ddd cannot be shortened
+            s = "\\"..s
+          else
+            s = "\\"..cv
+          end
+        elseif cc == delim then         -- \<delim>
+          s = "\\"..cc
+          c_delim = c_delim + 1
+        elseif cc == "\\" then          -- \\
+          s = "\\\\"
+        else                            -- literal character
+          s = cc
+          if cc == ndelim then
+            c_ndelim = c_ndelim + 1
+          end
+        end
+        z = sub(z, 1, i - 1)..s..sub(z, j)
+        i = i + #s
+
+      end--if p
+
+    else-- c ~= "\\"                    -- <other> -- no change
+      i = i + 1
+      if c == ndelim then  -- count ndelim, for switching delimiters
+        c_ndelim = c_ndelim + 1
+      end
+
+    end--if c
+  end--while
+
+  -- Switching delimiters, a long-winded derivation:
+  -- (1) delim takes 2+2*c_delim bytes, ndelim takes c_ndelim bytes
+  -- (2) delim becomes c_delim bytes, ndelim becomes 2+2*c_ndelim bytes
+  -- simplifying the condition (1)>(2) --> c_delim > c_ndelim
+  if c_delim > c_ndelim then
+    i = 1
+    while i <= #z do
+      local p, _, r = find(z, "([\'\"])", i)
+      if not p then break end
+      if r == delim then                -- \<delim> -> <delim>
+        z = sub(z, 1, p - 2)..sub(z, p)
+        i = p
+      else-- r == ndelim                -- <ndelim> -> \<ndelim>
+        z = sub(z, 1, p - 1).."\\"..sub(z, p)
+        i = p + 2
+      end
+    end--while
+    delim = ndelim  -- actually change delimiters
+  end
+
+  z = delim..z..delim
+  if z ~= sinfos[I] then
+    if opt_details then
+      print("<string> (line "..stoklns[I]..") "..sinfos[I].." -> "..z)
+      opt_details = opt_details + 1
+    end
+    sinfos[I] = z
+  end
+end
+
+--- Does long string optimization.
+--
+-- * remove first optional newline
+-- * normalize embedded newlines
+-- * reduce '=' separators in delimiters if possible
+--
+-- Note: warning flagged if trailing whitespace found, not trimmed.
+--
+-- @tparam int I
+local function do_lstring(I)
+  local info = sinfos[I]
+  local delim1 = match(info, "^%[=*%[")  -- cut out delimiters
+  local sep = #delim1
+  local delim2 = sub(info, -sep, -1)
+  local z = sub(info, sep + 1, -(sep + 1))  -- lstring without delims
+  local y = ""
+  local i = 1
+
+  while true do
+    local p, _, r, s = find(z, "([\r\n])([\r\n]?)", i)
+    -- deal with a single line
+    local ln
+    if not p then
+      ln = sub(z, i)
+    elseif p >= i then
+      ln = sub(z, i, p - 1)
+    end
+    if ln ~= "" then
+      -- flag a warning if there are trailing spaces, won't optimize!
+      if match(ln, "%s+$") then
+        M.warn.LSTRING = "trailing whitespace in long string near line "..stoklns[I]
+      end
+      y = y..ln
+    end
+    if not p then  -- done if no more EOLs
+      break
+    end
+    -- deal with line endings, normalize them
+    i = p + 1
+    if p then
+      if #s > 0 and r ~= s then  -- skip CRLF or LFCR
+        i = i + 1
+      end
+      -- skip first newline, which can be safely deleted
+      if not(i == 1 and i == p) then
+        y = y.."\n"
+      end
+    end
+  end--while
+
+  -- handle possible deletion of one or more '=' separators
+  if sep >= 3 then
+    local chk, okay = sep - 1
+    -- loop to test ending delimiter with less of '=' down to zero
+    while chk >= 2 do
+      local delim = "%]"..rep("=", chk - 2).."%]"
+      if not match(y.."]", delim) then okay = chk end
+      chk = chk - 1
+    end
+    if okay then  -- change delimiters
+      sep = rep("=", okay - 2)
+      delim1, delim2 = "["..sep.."[", "]"..sep.."]"
+    end
+  end
+
+  sinfos[I] = delim1..y..delim2
+end
+
+--- Does long comment optimization.
+--
+-- * trim trailing whitespace
+-- * normalize embedded newlines
+-- * reduce '=' separators in delimiters if possible
+--
+-- Note: It does not remove first optional newline.
+--
+-- @tparam int I
+local function do_lcomment(I)
+  local info = sinfos[I]
+  local delim1 = match(info, "^%-%-%[=*%[")  -- cut out delimiters
+  local sep = #delim1
+  local delim2 = sub(info, -(sep - 2), -1)
+  local z = sub(info, sep + 1, -(sep - 1))  -- comment without delims
+  local y = ""
+  local i = 1
+
+  while true do
+    local p, _, r, s = find(z, "([\r\n])([\r\n]?)", i)
+    -- deal with a single line, extract and check trailing whitespace
+    local ln
+    if not p then
+      ln = sub(z, i)
+    elseif p >= i then
+      ln = sub(z, i, p - 1)
+    end
+    if ln ~= "" then
+      -- trim trailing whitespace if non-empty line
+      local ws = match(ln, "%s*$")
+      if #ws > 0 then ln = sub(ln, 1, -(ws + 1)) end
+      y = y..ln
+    end
+    if not p then  -- done if no more EOLs
+      break
+    end
+    -- deal with line endings, normalize them
+    i = p + 1
+    if p then
+      if #s > 0 and r ~= s then  -- skip CRLF or LFCR
+        i = i + 1
+      end
+      y = y.."\n"
+    end
+  end--while
+
+  -- handle possible deletion of one or more '=' separators
+  sep = sep - 2
+  if sep >= 3 then
+    local chk, okay = sep - 1
+    -- loop to test ending delimiter with less of '=' down to zero
+    while chk >= 2 do
+      local delim = "%]"..rep("=", chk - 2).."%]"
+      if not match(y, delim) then okay = chk end
+      chk = chk - 1
+    end
+    if okay then  -- change delimiters
+      sep = rep("=", okay - 2)
+      delim1, delim2 = "--["..sep.."[", "]"..sep.."]"
+    end
+  end
+
+  sinfos[I] = delim1..y..delim2
+end
+
+--- Does short comment optimization.
+--
+-- * trim trailing whitespace
+--
+-- @tparam int i
+local function do_comment(i)
+  local info = sinfos[i]
+  local ws = match(info, "%s*$")        -- just look from end of string
+  if #ws > 0 then
+    info = sub(info, 1, -(ws + 1))      -- trim trailing whitespace
+  end
+  sinfos[i] = info
+end
+
+--- Returns true if string found in long comment.
+--
+-- This is a feature to keep copyright or license texts.
+--
+-- @tparam bool opt_keep
+-- @tparam string info
+-- @treturn bool
+local function keep_lcomment(opt_keep, info)
+  if not opt_keep then return false end  -- option not set
+  local delim1 = match(info, "^%-%-%[=*%[")  -- cut out delimiters
+  local sep = #delim1
+  local z = sub(info, sep + 1, -(sep - 1))  -- comment without delims
+  if find(z, opt_keep, 1, true) then  -- try to match
+    return true
+  end
+end
+
+--- The main entry point.
+--
+-- * currently, lexer processing has 2 passes
+-- * processing is done on a line-oriented basis, which is easier to
+--   grok due to the next point...
+-- * since there are various options that can be enabled or disabled,
+--   processing is a little messy or convoluted
+--
+-- @tparam {[string]=bool,...} option
+-- @tparam {string,...} toklist
+-- @tparam {string,...} semlist
+-- @tparam {int,...} toklnlist
+-- @treturn {string,...} toklist
+-- @treturn {string,...} semlist
+-- @treturn {int,...} toklnlist
+function M.optimize(option, toklist, semlist, toklnlist)
+  -- Set option flags.
+  local opt_comments = option["opt-comments"]
+  local opt_whitespace = option["opt-whitespace"]
+  local opt_emptylines = option["opt-emptylines"]
+  local opt_eols = option["opt-eols"]
+  local opt_strings = option["opt-strings"]
+  local opt_numbers = option["opt-numbers"]
+  local opt_x = option["opt-experimental"]
+  local opt_keep = option.KEEP
+  opt_details = option.DETAILS and 0  -- upvalues for details display
+  print = M.print or _G.print
+  if opt_eols then  -- forced settings, otherwise won't work properly
+    opt_comments = true
+    opt_whitespace = true
+    opt_emptylines = true
+  elseif opt_x then
+    opt_whitespace = true
+  end
+
+  -- Variable initialization.
+  stoks, sinfos, stoklns                -- set source lists
+    = toklist, semlist, toklnlist
+  local i = 1                           -- token position
+  local tok, info                       -- current token
+  local prev    -- position of last grammar token
+                -- on same line (for TK_SPACE stuff)
+
+  -- Changes a token, info pair.
+  local function settoken(tok, info, I)  --luacheck: ignore 431
+    I = I or i
+    stoks[I] = tok or ""
+    sinfos[I] = info or ""
+  end
+
+  -- Experimental optimization for ';' operator.
+  if opt_x then
+    while true do
+      tok, info = stoks[i], sinfos[i]
+      if tok == "TK_EOS" then           -- end of stream/pass
+        break
+      elseif tok == "TK_OP" and info == ";" then
+        -- ';' operator found, since it is entirely optional, set it
+        -- as a space to let whitespace optimization do the rest
+        settoken("TK_SPACE", " ")
+      end
+      i = i + 1
+    end
+    repack_tokens()
+  end
+
+  -- Processing loop (PASS 1)
+  i = 1
+  while true do
+    tok, info = stoks[i], sinfos[i]
+
+    local atstart = atlinestart(i)      -- set line begin flag
+    if atstart then prev = nil end
+
+    if tok == "TK_EOS" then             -- end of stream/pass
+      break
+
+    elseif tok == "TK_KEYWORD" or       -- keywords, identifiers,
+           tok == "TK_NAME" or          -- operators
+           tok == "TK_OP" then
+      -- TK_KEYWORD and TK_OP can't be optimized without a big
+      -- optimization framework; it would be more of an optimizing
+      -- compiler, not a source code compressor
+      -- TK_NAME that are locals needs parser to analyze/optimize
+      prev = i
+
+    elseif tok == "TK_NUMBER" then      -- numbers
+      if opt_numbers then
+        do_number(i)  -- optimize
+      end
+      prev = i
+
+    elseif tok == "TK_STRING" or        -- strings, long strings
+           tok == "TK_LSTRING" then
+      if opt_strings then
+        if tok == "TK_STRING" then
+          do_string(i)  -- optimize
+        else
+          do_lstring(i)  -- optimize
+        end
+      end
+      prev = i
+
+    elseif tok == "TK_COMMENT" then     -- short comments
+      if opt_comments then
+        if i == 1 and sub(info, 1, 1) == "#" then
+          -- keep shbang comment, trim whitespace
+          do_comment(i)
+        else
+          -- safe to delete, as a TK_EOL (or TK_EOS) always follows
+          settoken()  -- remove entirely
+        end
+      elseif opt_whitespace then        -- trim whitespace only
+        do_comment(i)
+      end
+
+    elseif tok == "TK_LCOMMENT" then    -- long comments
+      if keep_lcomment(opt_keep, info) then
+        -- if --keep, we keep a long comment if <msg> is found;
+        -- this is a feature to keep copyright or license texts
+        if opt_whitespace then          -- trim whitespace only
+          do_lcomment(i)
+        end
+        prev = i
+      elseif opt_comments then
+        local eols = commenteols(info)
+
+        -- prepare opt_emptylines case first, if a disposable token
+        -- follows, current one is safe to dump, else keep a space;
+        -- it is implied that the operation is safe for '-', because
+        -- current is a TK_LCOMMENT, and must be separate from a '-'
+        if is_faketoken[stoks[i + 1]] then
+          settoken()  -- remove entirely
+          tok = ""
+        else
+          settoken("TK_SPACE", " ")
+        end
+
+        -- if there are embedded EOLs to keep and opt_emptylines is
+        -- disabled, then switch the token into one or more EOLs
+        if not opt_emptylines and eols > 0 then
+          settoken("TK_EOL", rep("\n", eols))
+        end
+
+        -- if optimizing whitespaces, force reinterpretation of the
+        -- token to give a chance for the space to be optimized away
+        if opt_whitespace and tok ~= "" then
+          i = i - 1  -- to reinterpret
+        end
+      else                              -- disabled case
+        if opt_whitespace then          -- trim whitespace only
+          do_lcomment(i)
+        end
+        prev = i
+      end
+
+    elseif tok == "TK_EOL" then         -- line endings
+      if atstart and opt_emptylines then
+        settoken()  -- remove entirely
+      elseif info == "\r\n" or info == "\n\r" then
+        -- normalize the rest of the EOLs for CRLF/LFCR only
+        -- (note that TK_LCOMMENT can change into several EOLs)
+        settoken("TK_EOL", "\n")
+      end
+
+    elseif tok == "TK_SPACE" then       -- whitespace
+      if opt_whitespace then
+        if atstart or atlineend(i) then
+          -- delete leading and trailing whitespace
+          settoken()  -- remove entirely
+        else
+
+          -- at this point, since leading whitespace have been removed,
+          -- there should be a either a real token or a TK_LCOMMENT
+          -- prior to hitting this whitespace; the TK_LCOMMENT case
+          -- only happens if opt_comments is disabled; so prev ~= nil
+          local ptok = stoks[prev]
+          if ptok == "TK_LCOMMENT" then
+            -- previous TK_LCOMMENT can abut with anything
+            settoken()  -- remove entirely
+          else
+            -- prev must be a grammar token; consecutive TK_SPACE
+            -- tokens is impossible when optimizing whitespace
+            local ntok = stoks[i + 1]
+            if is_faketoken[ntok] then
+              -- handle special case where a '-' cannot abut with
+              -- either a short comment or a long comment
+              if (ntok == "TK_COMMENT" or ntok == "TK_LCOMMENT") and
+                 ptok == "TK_OP" and sinfos[prev] == "-" then
+                -- keep token
+              else
+                settoken()  -- remove entirely
+              end
+            else--is_realtoken
+              -- check a pair of grammar tokens, if can abut, then
+              -- delete space token entirely, otherwise keep one space
+              local s = checkpair(prev, i + 1)
+              if s == "" then
+                settoken()  -- remove entirely
+              else
+                settoken("TK_SPACE", " ")
+              end
+            end
+          end
+
+        end
+      end
+
+    else
+      error("unidentified token encountered")
+    end
+
+    i = i + 1
+  end--while
+  repack_tokens()
+
+  -- Processing loop (PASS 2)
+  if opt_eols then
+    i = 1
+    -- Aggressive EOL removal only works with most non-grammar tokens
+    -- optimized away because it is a rather simple scheme -- basically
+    -- it just checks 'real' token pairs around EOLs.
+    if stoks[1] == "TK_COMMENT" then
+      -- first comment still existing must be shbang, skip whole line
+      i = 3
+    end
+    while true do
+      tok = stoks[i]
+
+      if tok == "TK_EOS" then           -- end of stream/pass
+        break
+
+      elseif tok == "TK_EOL" then       -- consider each TK_EOL
+        local t1, t2 = stoks[i - 1], stoks[i + 1]
+        if is_realtoken[t1] and is_realtoken[t2] then  -- sanity check
+          local s = checkpair(i - 1, i + 1)
+          if s == "" or t2 == "TK_EOS" then
+            settoken()  -- remove entirely
+          end
+        end
+      end--if tok
+
+      i = i + 1
+    end--while
+    repack_tokens()
+  end
+
+  if opt_details and opt_details > 0 then print() end -- spacing
+  return stoks, sinfos, stoklns
+end
+
+return M

tools/luasrcdiet/optparser.lua

@@ -0,0 +1,644 @@
+---------
+-- This module does parser-based optimizations.
+--
+-- **Notes:**
+--
+-- * The processing load is quite significant, but since this is an
+--   off-line text processor, I believe we can wait a few seconds.
+-- * TODO: Might process "local a,a,a" wrongly... need tests!
+-- * TODO: Remove position handling if overlapped locals (rem < 0)
+--   needs more study, to check behaviour.
+-- * TODO: There are probably better ways to do allocation, e.g. by
+--   choosing better methods to sort and pick locals...
+-- * TODO: We don't need 53*63 two-letter identifiers; we can make
+--   do with significantly less depending on how many that are really
+--   needed and improve entropy; e.g. 13 needed -> choose 4*4 instead.
+----
+local byte = string.byte
+local char = string.char
+local concat = table.concat
+local fmt = string.format
+local pairs = pairs
+local rep = string.rep
+local sort = table.sort
+local sub = string.sub
+
+
+local M = {}
+
+-- Letter frequencies for reducing symbol entropy (fixed version)
+-- * Might help a wee bit when the output file is compressed
+-- * See Wikipedia: http://en.wikipedia.org/wiki/Letter_frequencies
+-- * We use letter frequencies according to a Linotype keyboard, plus
+--   the underscore, and both lower case and upper case letters.
+-- * The arrangement below (LC, underscore, %d, UC) is arbitrary.
+-- * This is certainly not optimal, but is quick-and-dirty and the
+--   process has no significant overhead
+local LETTERS = "etaoinshrdlucmfwypvbgkqjxz_ETAOINSHRDLUCMFWYPVBGKQJXZ"
+local ALPHANUM = "etaoinshrdlucmfwypvbgkqjxz_0123456789ETAOINSHRDLUCMFWYPVBGKQJXZ"
+
+-- Names or identifiers that must be skipped.
+-- (The first two lines are for keywords.)
+local SKIP_NAME = {}
+for v in ([[
+and break do else elseif end false for function if in
+local nil not or repeat return then true until while
+self _ENV]]):gmatch("%S+") do
+  SKIP_NAME[v] = true
+end
+
+
+local toklist, seminfolist,             -- token lists (lexer output)
+      tokpar, seminfopar, xrefpar,      -- token lists (parser output)
+      globalinfo, localinfo,            -- variable information tables
+      statinfo,                         -- statment type table
+      globaluniq, localuniq,            -- unique name tables
+      var_new,                          -- index of new variable names
+      varlist                           -- list of output variables
+
+--- Preprocesses information table to get lists of unique names.
+--
+-- @tparam {table,...} infotable
+-- @treturn table
+local function preprocess(infotable)
+  local uniqtable = {}
+  for i = 1, #infotable do              -- enumerate info table
+    local obj = infotable[i]
+    local name = obj.name
+
+    if not uniqtable[name] then         -- not found, start an entry
+      uniqtable[name] = {
+        decl = 0, token = 0, size = 0,
+      }
+    end
+
+    local uniq = uniqtable[name]        -- count declarations, tokens, size
+    uniq.decl = uniq.decl + 1
+    local xref = obj.xref
+    local xcount = #xref
+    uniq.token = uniq.token + xcount
+    uniq.size = uniq.size + xcount * #name
+
+    if obj.decl then            -- if local table, create first,last pairs
+      obj.id = i
+      obj.xcount = xcount
+      if xcount > 1 then        -- if ==1, means local never accessed
+        obj.first = xref[2]
+        obj.last = xref[xcount]
+      end
+
+    else                        -- if global table, add a back ref
+      uniq.id = i
+    end
+
+  end--for
+  return uniqtable
+end
+
+--- Calculates actual symbol frequencies, in order to reduce entropy.
+--
+-- * This may help further reduce the size of compressed sources.
+-- * Note that since parsing optimizations is put before lexing
+--   optimizations, the frequency table is not exact!
+-- * Yes, this will miss --keep block comments too...
+--
+-- @tparam table option
+local function recalc_for_entropy(option)
+  -- table of token classes to accept in calculating symbol frequency
+  local ACCEPT = {
+    TK_KEYWORD = true, TK_NAME = true, TK_NUMBER = true,
+    TK_STRING = true, TK_LSTRING = true,
+  }
+  if not option["opt-comments"] then
+    ACCEPT.TK_COMMENT = true
+    ACCEPT.TK_LCOMMENT = true
+  end
+
+  -- Create a new table and remove any original locals by filtering.
+  local filtered = {}
+  for i = 1, #toklist do
+    filtered[i] = seminfolist[i]
+  end
+  for i = 1, #localinfo do              -- enumerate local info table
+    local obj = localinfo[i]
+    local xref = obj.xref
+    for j = 1, obj.xcount do
+      local p = xref[j]
+      filtered[p] = ""                  -- remove locals
+    end
+  end
+
+  local freq = {}                       -- reset symbol frequency table
+  for i = 0, 255 do freq[i] = 0 end
+  for i = 1, #toklist do                -- gather symbol frequency
+    local tok, info = toklist[i], filtered[i]
+    if ACCEPT[tok] then
+      for j = 1, #info do
+        local c = byte(info, j)
+        freq[c] = freq[c] + 1
+      end
+    end--if
+  end--for
+
+  -- Re-sorts symbols according to actual frequencies.
+  --
+  -- @tparam string symbols
+  -- @treturn string
+  local function resort(symbols)
+    local symlist = {}
+    for i = 1, #symbols do              -- prepare table to sort
+      local c = byte(symbols, i)
+      symlist[i] = { c = c, freq = freq[c], }
+    end
+    sort(symlist, function(v1, v2)  -- sort selected symbols
+        return v1.freq > v2.freq
+      end)
+    local charlist = {}                 -- reconstitute the string
+    for i = 1, #symlist do
+      charlist[i] = char(symlist[i].c)
+    end
+    return concat(charlist)
+  end
+
+  LETTERS = resort(LETTERS)             -- change letter arrangement
+  ALPHANUM = resort(ALPHANUM)
+end
+
+--- Returns a string containing a new local variable name to use, and
+-- a flag indicating whether it collides with a global variable.
+--
+-- Trapping keywords and other names like 'self' is done elsewhere.
+--
+-- @treturn string A new local variable name.
+-- @treturn bool Whether the name collides with a global variable.
+local function new_var_name()
+  local var
+  local cletters, calphanum = #LETTERS, #ALPHANUM
+  local v = var_new
+  if v < cletters then                  -- single char
+    v = v + 1
+    var = sub(LETTERS, v, v)
+  else                                  -- longer names
+    local range, sz = cletters, 1       -- calculate # chars fit
+    repeat
+      v = v - range
+      range = range * calphanum
+      sz = sz + 1
+    until range > v
+    local n = v % cletters              -- left side cycles faster
+    v = (v - n) / cletters              -- do first char first
+    n = n + 1
+    var = sub(LETTERS, n, n)
+    while sz > 1 do
+      local m = v % calphanum
+      v = (v - m) / calphanum
+      m = m + 1
+      var = var..sub(ALPHANUM, m, m)
+      sz = sz - 1
+    end
+  end
+  var_new = var_new + 1
+  return var, globaluniq[var] ~= nil
+end
+
+--- Calculates and prints some statistics.
+--
+-- Note: probably better in main source, put here for now.
+--
+-- @tparam table globaluniq
+-- @tparam table localuniq
+-- @tparam table afteruniq
+-- @tparam table option
+local function stats_summary(globaluniq, localuniq, afteruniq, option)  --luacheck: ignore 431
+  local print = M.print or print
+  local opt_details = option.DETAILS
+  if option.QUIET then return end
+
+  local uniq_g , uniq_li, uniq_lo = 0, 0, 0
+  local decl_g, decl_li, decl_lo = 0, 0, 0
+  local token_g, token_li, token_lo = 0, 0, 0
+  local size_g, size_li, size_lo = 0, 0, 0
+
+  local function avg(c, l)              -- safe average function
+    if c == 0 then return 0 end
+    return l / c
+  end
+
+  -- Collect statistics (Note: globals do not have declarations!)
+  for _, uniq in pairs(globaluniq) do
+    uniq_g = uniq_g + 1
+    token_g = token_g + uniq.token
+    size_g = size_g + uniq.size
+  end
+  for _, uniq in pairs(localuniq) do
+    uniq_li = uniq_li + 1
+    decl_li = decl_li + uniq.decl
+    token_li = token_li + uniq.token
+    size_li = size_li + uniq.size
+  end
+  for _, uniq in pairs(afteruniq) do
+    uniq_lo = uniq_lo + 1
+    decl_lo = decl_lo + uniq.decl
+    token_lo = token_lo + uniq.token
+    size_lo = size_lo + uniq.size
+  end
+  local uniq_ti = uniq_g + uniq_li
+  local decl_ti = decl_g + decl_li
+  local token_ti = token_g + token_li
+  local size_ti = size_g + size_li
+  local uniq_to = uniq_g + uniq_lo
+  local decl_to = decl_g + decl_lo
+  local token_to = token_g + token_lo
+  local size_to = size_g + size_lo
+
+  -- Detailed stats: global list
+  if opt_details then
+    local sorted = {} -- sort table of unique global names by size
+    for name, uniq in pairs(globaluniq) do
+      uniq.name = name
+      sorted[#sorted + 1] = uniq
+    end
+    sort(sorted, function(v1, v2)
+        return v1.size > v2.size
+      end)
+
+    do
+      local tabf1, tabf2 = "%8s%8s%10s  %s", "%8d%8d%10.2f  %s"
+      local hl = rep("-", 44)
+      print("*** global variable list (sorted by size) ***\n"..hl)
+      print(fmt(tabf1, "Token",  "Input", "Input", "Global"))
+      print(fmt(tabf1, "Count", "Bytes", "Average", "Name"))
+      print(hl)
+      for i = 1, #sorted do
+        local uniq = sorted[i]
+        print(fmt(tabf2, uniq.token, uniq.size, avg(uniq.token, uniq.size), uniq.name))
+      end
+      print(hl)
+      print(fmt(tabf2, token_g, size_g, avg(token_g, size_g), "TOTAL"))
+      print(hl.."\n")
+    end
+
+    -- Detailed stats: local list
+    do
+      local tabf1, tabf2 = "%8s%8s%8s%10s%8s%10s  %s", "%8d%8d%8d%10.2f%8d%10.2f  %s"
+      local hl = rep("-", 70)
+      print("*** local variable list (sorted by allocation order) ***\n"..hl)
+      print(fmt(tabf1, "Decl.", "Token",  "Input", "Input", "Output", "Output", "Global"))
+      print(fmt(tabf1, "Count", "Count", "Bytes", "Average", "Bytes", "Average", "Name"))
+      print(hl)
+      for i = 1, #varlist do  -- iterate according to order assigned
+        local name = varlist[i]
+        local uniq = afteruniq[name]
+        local old_t, old_s = 0, 0
+        for j = 1, #localinfo do  -- find corresponding old names and calculate
+          local obj = localinfo[j]
+          if obj.name == name then
+            old_t = old_t + obj.xcount
+            old_s = old_s + obj.xcount * #obj.oldname
+          end
+        end
+        print(fmt(tabf2, uniq.decl, uniq.token, old_s, avg(old_t, old_s),
+                  uniq.size, avg(uniq.token, uniq.size), name))
+      end
+      print(hl)
+      print(fmt(tabf2, decl_lo, token_lo, size_li, avg(token_li, size_li),
+                size_lo, avg(token_lo, size_lo), "TOTAL"))
+      print(hl.."\n")
+    end
+  end--if opt_details
+
+  -- Display output
+  do
+    local tabf1, tabf2 = "%-16s%8s%8s%8s%8s%10s", "%-16s%8d%8d%8d%8d%10.2f"
+    local hl = rep("-", 58)
+    print("*** local variable optimization summary ***\n"..hl)
+    print(fmt(tabf1, "Variable",  "Unique", "Decl.", "Token", "Size", "Average"))
+    print(fmt(tabf1, "Types", "Names", "Count", "Count", "Bytes", "Bytes"))
+    print(hl)
+    print(fmt(tabf2, "Global", uniq_g, decl_g, token_g, size_g, avg(token_g, size_g)))
+    print(hl)
+    print(fmt(tabf2, "Local (in)", uniq_li, decl_li, token_li, size_li, avg(token_li, size_li)))
+    print(fmt(tabf2, "TOTAL (in)", uniq_ti, decl_ti, token_ti, size_ti, avg(token_ti, size_ti)))
+    print(hl)
+    print(fmt(tabf2, "Local (out)", uniq_lo, decl_lo, token_lo, size_lo, avg(token_lo, size_lo)))
+    print(fmt(tabf2, "TOTAL (out)", uniq_to, decl_to, token_to, size_to, avg(token_to, size_to)))
+    print(hl.."\n")
+  end
+end
+
+--- Does experimental optimization for f("string") statements.
+--
+-- It's safe to delete parentheses without adding whitespace, as both
+-- kinds of strings can abut with anything else.
+local function optimize_func1()
+
+  local function is_strcall(j)          -- find f("string") pattern
+    local t1 = tokpar[j + 1] or ""
+    local t2 = tokpar[j + 2] or ""
+    local t3 = tokpar[j + 3] or ""
+    if t1 == "(" and t2 == "<string>" and t3 == ")" then
+      return true
+    end
+  end
+
+  local del_list = {}           -- scan for function pattern,
+  local i = 1                   -- tokens to be deleted are marked
+  while i <= #tokpar do
+    local id = statinfo[i]
+    if id == "call" and is_strcall(i) then  -- found & mark ()
+      del_list[i + 1] = true    -- '('
+      del_list[i + 3] = true    -- ')'
+      i = i + 3
+    end
+    i = i + 1
+  end
+
+  -- Delete a token and adjust all relevant tables.
+  -- * Currently invalidates globalinfo and localinfo (not updated),
+  --   so any other optimization is done after processing locals
+  --   (of course, we can also lex the source data again...).
+  -- * Faster one-pass token deletion.
+  local del_list2 = {}
+  do
+    local i, dst, idend = 1, 1, #tokpar
+    while dst <= idend do         -- process parser tables
+      if del_list[i] then         -- found a token to delete?
+        del_list2[xrefpar[i]] = true
+        i = i + 1
+      end
+      if i > dst then
+        if i <= idend then        -- shift table items lower
+          tokpar[dst] = tokpar[i]
+          seminfopar[dst] = seminfopar[i]
+          xrefpar[dst] = xrefpar[i] - (i - dst)
+          statinfo[dst] = statinfo[i]
+        else                      -- nil out excess entries
+          tokpar[dst] = nil
+          seminfopar[dst] = nil
+          xrefpar[dst] = nil
+          statinfo[dst] = nil
+        end
+      end
+      i = i + 1
+      dst = dst + 1
+    end
+  end
+
+  do
+    local i, dst, idend = 1, 1, #toklist
+    while dst <= idend do         -- process lexer tables
+      if del_list2[i] then        -- found a token to delete?
+        i = i + 1
+      end
+      if i > dst then
+        if i <= idend then        -- shift table items lower
+          toklist[dst] = toklist[i]
+          seminfolist[dst] = seminfolist[i]
+        else                      -- nil out excess entries
+          toklist[dst] = nil
+          seminfolist[dst] = nil
+        end
+      end
+      i = i + 1
+      dst = dst + 1
+    end
+  end
+end
+
+--- Does local variable optimization.
+--
+-- @tparam {[string]=bool,...} option
+local function optimize_locals(option)
+  var_new = 0                           -- reset variable name allocator
+  varlist = {}
+
+  -- Preprocess global/local tables, handle entropy reduction.
+  globaluniq = preprocess(globalinfo)
+  localuniq = preprocess(localinfo)
+  if option["opt-entropy"] then         -- for entropy improvement
+    recalc_for_entropy(option)
+  end
+
+  -- Build initial declared object table, then sort according to
+  -- token count, this might help assign more tokens to more common
+  -- variable names such as 'e' thus possibly reducing entropy.
+  -- * An object knows its localinfo index via its 'id' field.
+  -- * Special handling for "self" and "_ENV" special local (parameter) here.
+  local object = {}
+  for i = 1, #localinfo do
+    object[i] = localinfo[i]
+  end
+  sort(object, function(v1, v2)  -- sort largest first
+      return v1.xcount > v2.xcount
+    end)
+
+  -- The special "self" and "_ENV" function parameters must be preserved.
+  -- * The allocator below will never use "self", so it is safe to
+  --   keep those implicit declarations as-is.
+  local temp, j, used_specials = {}, 1, {}
+  for i = 1, #object do
+    local obj = object[i]
+    if not obj.is_special then
+      temp[j] = obj
+      j = j + 1
+    else
+      used_specials[#used_specials + 1] = obj.name
+    end
+  end
+  object = temp
+
+  -- A simple first-come first-served heuristic name allocator,
+  -- note that this is in no way optimal...
+  -- * Each object is a local variable declaration plus existence.
+  -- * The aim is to assign short names to as many tokens as possible,
+  --   so the following tries to maximize name reuse.
+  -- * Note that we preserve sort order.
+  local nobject = #object
+  while nobject > 0 do
+    local varname, gcollide
+    repeat
+      varname, gcollide = new_var_name()  -- collect a variable name
+    until not SKIP_NAME[varname]          -- skip all special names
+    varlist[#varlist + 1] = varname       -- keep a list
+    local oleft = nobject
+
+    -- If variable name collides with an existing global, the name
+    -- cannot be used by a local when the name is accessed as a global
+    -- during which the local is alive (between 'act' to 'rem'), so
+    -- we drop objects that collides with the corresponding global.
+    if gcollide then
+      -- find the xref table of the global
+      local gref = globalinfo[globaluniq[varname].id].xref
+      local ngref = #gref
+      -- enumerate for all current objects; all are valid at this point
+      for i = 1, nobject do
+        local obj = object[i]
+        local act, rem = obj.act, obj.rem  -- 'live' range of local
+        -- if rem < 0, it is a -id to a local that had the same name
+        -- so follow rem to extend it; does this make sense?
+        while rem < 0 do
+          rem = localinfo[-rem].rem
+        end
+        local drop
+        for j = 1, ngref do
+          local p = gref[j]
+          if p >= act and p <= rem then drop = true end  -- in range?
+        end
+        if drop then
+          obj.skip = true
+          oleft = oleft - 1
+        end
+      end--for
+    end--if gcollide
+
+    -- Now the first unassigned local (since it's sorted) will be the
+    -- one with the most tokens to rename, so we set this one and then
+    -- eliminate all others that collides, then any locals that left
+    -- can then reuse the same variable name; this is repeated until
+    -- all local declaration that can use this name is assigned.
+    --
+    -- The criteria for local-local reuse/collision is:
+    --   A is the local with a name already assigned
+    --   B is the unassigned local under consideration
+    --   => anytime A is accessed, it cannot be when B is 'live'
+    --   => to speed up things, we have first/last accesses noted
+    while oleft > 0 do
+      local i = 1
+      while object[i].skip do  -- scan for first object
+        i = i + 1
+      end
+
+      -- First object is free for assignment of the variable name
+      -- [first,last] gives the access range for collision checking.
+      oleft = oleft - 1
+      local obja = object[i]
+      i = i + 1
+      obja.newname = varname
+      obja.skip = true
+      obja.done = true
+      local first, last = obja.first, obja.last
+      local xref = obja.xref
+
+      -- Then, scan all the rest and drop those colliding.
+      -- If A was never accessed then it'll never collide with anything
+      -- otherwise trivial skip if:
+      -- * B was activated after A's last access (last < act),
+      -- * B was removed before A's first access (first > rem),
+      -- if not, see detailed skip below...
+      if first and oleft > 0 then  -- must have at least 1 access
+        local scanleft = oleft
+        while scanleft > 0 do
+          while object[i].skip do  -- next valid object
+            i = i + 1
+          end
+          scanleft = scanleft - 1
+          local objb = object[i]
+          i = i + 1
+          local act, rem = objb.act, objb.rem  -- live range of B
+          -- if rem < 0, extend range of rem thru' following local
+          while rem < 0 do
+            rem = localinfo[-rem].rem
+          end
+
+          if not(last < act or first > rem) then  -- possible collision
+
+            -- B is activated later than A or at the same statement,
+            -- this means for no collision, A cannot be accessed when B
+            -- is alive, since B overrides A (or is a peer).
+            if act >= obja.act then
+              for j = 1, obja.xcount do  -- ... then check every access
+                local p = xref[j]
+                if p >= act and p <= rem then  -- A accessed when B live!
+                  oleft = oleft - 1
+                  objb.skip = true
+                  break
+                end
+              end--for
+
+            -- A is activated later than B, this means for no collision,
+            -- A's access is okay since it overrides B, but B's last
+            -- access need to be earlier than A's activation time.
+            else
+              if objb.last and objb.last >= obja.act then
+                oleft = oleft - 1
+                objb.skip = true
+              end
+            end
+          end
+
+          if oleft == 0 then break end
+        end
+      end--if first
+
+    end--while
+
+    -- After assigning all possible locals to one variable name, the
+    -- unassigned locals/objects have the skip field reset and the table
+    -- is compacted, to hopefully reduce iteration time.
+    local temp, j = {}, 1
+    for i = 1, nobject do
+      local obj = object[i]
+      if not obj.done then
+        obj.skip = false
+        temp[j] = obj
+        j = j + 1
+      end
+    end
+    object = temp  -- new compacted object table
+    nobject = #object  -- objects left to process
+
+  end--while
+
+  -- After assigning all locals with new variable names, we can
+  -- patch in the new names, and reprocess to get 'after' stats.
+  for i = 1, #localinfo do  -- enumerate all locals
+    local obj = localinfo[i]
+    local xref = obj.xref
+    if obj.newname then                 -- if got new name, patch it in
+      for j = 1, obj.xcount do
+        local p = xref[j]               -- xrefs indexes the token list
+        seminfolist[p] = obj.newname
+      end
+      obj.name, obj.oldname             -- adjust names
+        = obj.newname, obj.name
+    else
+      obj.oldname = obj.name            -- for cases like 'self'
+    end
+  end
+
+  -- Deal with statistics output.
+  for _, name in ipairs(used_specials) do
+    varlist[#varlist + 1] = name
+  end
+  local afteruniq = preprocess(localinfo)
+  stats_summary(globaluniq, localuniq, afteruniq, option)
+end
+
+--- The main entry point.
+--
+-- @tparam table option
+-- @tparam {string,...} _toklist
+-- @tparam {string,...} _seminfolist
+-- @tparam table xinfo
+function M.optimize(option, _toklist, _seminfolist, xinfo)
+  -- set tables
+  toklist, seminfolist                  -- from lexer
+    = _toklist, _seminfolist
+  tokpar, seminfopar, xrefpar           -- from parser
+    = xinfo.toklist, xinfo.seminfolist, xinfo.xreflist
+  globalinfo, localinfo, statinfo       -- from parser
+    = xinfo.globalinfo, xinfo.localinfo, xinfo.statinfo
+
+  -- Optimize locals.
+  if option["opt-locals"] then
+    optimize_locals(option)
+  end
+
+  -- Other optimizations.
+  if option["opt-experimental"] then    -- experimental
+    optimize_func1()
+    -- WARNING globalinfo and localinfo now invalidated!
+  end
+end
+
+return M

tools/luasrcdiet/plugin/example.lua

@@ -0,0 +1,90 @@
+---------
+-- Example of a plugin for LuaSrcDiet.
+--
+-- WARNING: highly experimental! interface liable to change
+--
+-- **Notes:**
+--
+-- * Any function can be omitted and LuaSrcDiet won't call it.
+-- * The functions are:
+--   (1) init(_option, _srcfl, _destfl)
+--   (2) post_load(z) can return z
+--   (3) post_lex(toklist, seminfolist, toklnlist)
+--   (4) post_parse(globalinfo, localinfo)
+--   (5) post_optparse()
+--   (6) post_optlex(toklist, seminfolist, toklnlist)
+-- * Older tables can be copied and kept in the plugin and used later.
+-- * If you modify 'option', remember that LuaSrcDiet might be
+--   processing more than one file.
+-- * Arrangement of the functions is not final!
+-- * TODO: can't process additional options from command line yet
+----
+
+local M = {}
+
+local option                    -- local reference to list of options
+local srcfl, destfl             -- filenames
+local old_quiet
+
+local function print(...)               -- handle quiet option
+  if option.QUIET then return end
+  _G.print(...)
+end
+
+--- Initialization.
+--
+-- @tparam {[string]=bool,...} _option
+-- @tparam string _srcfl Path of the source file.
+-- @tparam string _destfl Path of the destination file.
+function M.init(_option, _srcfl, _destfl)
+  option = _option
+  srcfl, destfl = _srcfl, _destfl
+  -- plugin can impose its own option starting from here
+end
+
+--- Message display, post-load processing, can return z.
+function M.post_load(z)
+  -- this message will print after the LuaSrcDiet title message
+  print([[
+Example plugin module for LuaSrcDiet
+]])
+  print("Example: source file name is '"..srcfl.."'")
+  print("Example: destination file name is '"..destfl.."'")
+  print("Example: the size of the source file is "..#z.." bytes")
+  -- returning z is optional; this allows optional replacement of
+  -- the source data prior to lexing
+  return z
+end
+
+--- Post-lexing processing, can work on lexer table output.
+function M.post_lex(toklist, seminfolist, toklnlist)  --luacheck: ignore
+  print("Example: the number of lexed elements is "..#toklist)
+end
+
+--- Post-parsing processing, gives globalinfo, localinfo.
+function M.post_parse(globalinfo, localinfo)
+  print("Example: size of globalinfo is "..#globalinfo)
+  print("Example: size of localinfo is "..#localinfo)
+  old_quiet = option.QUIET
+  option.QUIET = true
+end
+
+--- Post-parser optimization processing, can get tables from elsewhere.
+function M.post_optparse()
+  option.QUIET = old_quiet
+  print("Example: pretend to do post-optparse")
+end
+
+--- Post-lexer optimization processing, can get tables from elsewhere.
+function M.post_optlex(toklist, seminfolist, toklnlist)  --luacheck: ignore
+  print("Example: pretend to do post-optlex")
+  -- restore old settings, other file might need original settings
+  option.QUIET = old_quiet
+  -- option.EXIT can be set at the end of any post_* function to stop
+  -- further processing and exit for the current file being worked on
+  -- in this case, final stats printout is disabled and the output will
+  -- not be written to the destination file
+  option.EXIT = true
+end
+
+return M

tools/luasrcdiet/plugin/html.lua

@@ -0,0 +1,177 @@
+---------
+-- Turns Lua 5.1 source code into HTML files.
+--
+-- WARNING: highly experimental! interface liable to change
+--
+-- **Notes:**
+--
+-- * This HTML highlighter marks globals brightly so that their usage
+--   can be manually optimized.
+-- * Either uses a .html extension for output files or it follows the
+--   -o <filespec> option.
+-- * The HTML style tries to follow that of the Lua wiki.
+----
+local fs = require "luasrcdiet.fs"
+
+local concat = table.concat
+local find = string.find
+local fmt = string.format
+local sub = string.sub
+
+local M = {}
+
+local HTML_EXT = ".html"
+local ENTITIES = {
+  ["&"] = "&amp;", ["<"] = "&lt;", [">"] = "&gt;",
+  ["'"] = "&apos;", ["\""] = "&quot;",
+}
+
+-- simple headers and footers
+local HEADER = [[
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<html>
+<head>
+<title>%s</title>
+<meta name="Generator" content="LuaSrcDiet">
+<style type="text/css">
+%s</style>
+</head>
+<body>
+<pre class="code">
+]]
+local FOOTER = [[
+</pre>
+</body>
+</html>
+]]
+-- for more, please see wikimain.css from the Lua wiki site
+local STYLESHEET = [[
+BODY {
+    background: white;
+    color: navy;
+}
+pre.code { color: black; }
+span.comment { color: #00a000; }
+span.string  { color: #009090; }
+span.keyword { color: black; font-weight: bold; }
+span.number { color: #993399; }
+span.operator { }
+span.name { }
+span.global { color: #ff0000; font-weight: bold; }
+span.local { color: #0000ff; font-weight: bold; }
+]]
+
+local option                    -- local reference to list of options
+local srcfl, destfl             -- filenames
+local toklist, seminfolist  -- token data
+
+local function print(...)               -- handle quiet option
+  if option.QUIET then return end
+  _G.print(...)
+end
+
+--- Initialization.
+function M.init(_option, _srcfl)
+  option = _option
+  srcfl = _srcfl
+  local extb, _ = find(srcfl, "%.[^%.%\\%/]*$")
+  local basename = srcfl
+  if extb and extb > 1 then
+    basename = sub(srcfl, 1, extb - 1)
+  end
+  destfl = basename..HTML_EXT
+  if option.OUTPUT_FILE then
+    destfl = option.OUTPUT_FILE
+  end
+  if srcfl == destfl then
+    error("output filename identical to input filename")
+  end
+end
+
+--- Message display, post-load processing.
+function M.post_load()
+  print([[
+HTML plugin module for LuaSrcDiet
+]])
+  print("Exporting: "..srcfl.." -> "..destfl.."\n")
+end
+
+--- Post-lexing processing, can work on lexer table output.
+function M.post_lex(_toklist, _seminfolist)
+  toklist, seminfolist = _toklist, _seminfolist
+end
+
+--- Escapes the usual suspects for HTML/XML.
+local function do_entities(z)
+  local i = 1
+  while i <= #z do
+    local c = sub(z, i, i)
+    local d = ENTITIES[c]
+    if d then
+      c = d
+      z = sub(z, 1, i - 1)..c..sub(z, i + 1)
+    end
+    i = i + #c
+  end--while
+  return z
+end
+
+--- Post-parsing processing, gives globalinfo, localinfo.
+function M.post_parse(globalinfo, localinfo)
+  local html = {}
+  local function add(s)         -- html helpers
+    html[#html + 1] = s
+  end
+  local function span(class, s)
+    add('<span class="'..class..'">'..s..'</span>')
+  end
+
+  for i = 1, #globalinfo do     -- mark global identifiers as TK_GLOBAL
+    local obj = globalinfo[i]
+    local xref = obj.xref
+    for j = 1, #xref do
+      local p = xref[j]
+      toklist[p] = "TK_GLOBAL"
+    end
+  end--for
+
+  for i = 1, #localinfo do      -- mark local identifiers as TK_LOCAL
+    local obj = localinfo[i]
+    local xref = obj.xref
+    for j = 1, #xref do
+      local p = xref[j]
+      toklist[p] = "TK_LOCAL"
+    end
+  end--for
+
+  add(fmt(HEADER,     -- header and leading stuff
+    do_entities(srcfl),
+    STYLESHEET))
+  for i = 1, #toklist do        -- enumerate token list
+    local tok, info = toklist[i], seminfolist[i]
+    if tok == "TK_KEYWORD" then
+      span("keyword", info)
+    elseif tok == "TK_STRING" or tok == "TK_LSTRING" then
+      span("string", do_entities(info))
+    elseif tok == "TK_COMMENT" or tok == "TK_LCOMMENT" then
+      span("comment", do_entities(info))
+    elseif tok == "TK_GLOBAL" then
+      span("global", info)
+    elseif tok == "TK_LOCAL" then
+      span("local", info)
+    elseif tok == "TK_NAME" then
+      span("name", info)
+    elseif tok == "TK_NUMBER" then
+      span("number", info)
+    elseif tok == "TK_OP" then
+      span("operator", do_entities(info))
+    elseif tok ~= "TK_EOS" then  -- TK_EOL, TK_SPACE
+      add(info)
+    end
+  end--for
+  add(FOOTER)
+  assert(fs.write_file(destfl, concat(html), "wb"))
+  option.EXIT = true
+end
+
+return M

tools/luasrcdiet/plugin/sloc.lua

@@ -0,0 +1,89 @@
+---------
+-- Calculates SLOC for Lua 5.1 scripts
+--
+-- WARNING: highly experimental! interface liable to change
+--
+-- **Notes:**
+--
+-- * SLOC's behaviour is based on David Wheeler's SLOCCount.
+-- * Empty lines and comment don't count as significant.
+-- * Empty lines in long strings are also insignificant. This is
+--   debatable. In SLOCCount, this allows counting of invalid multi-
+--   line strings for C. But an empty line is still an empty line.
+-- * Ignores the --quiet option, print own result line.
+----
+
+local M = {}
+
+local option                    -- local reference to list of options
+local srcfl                     -- source file name
+
+function M.init(_option, _srcfl)
+  option = _option
+  option.QUIET = true
+  srcfl = _srcfl
+end
+
+--- Splits a block into a table of lines (minus EOLs).
+--
+-- @tparam string blk
+-- @treturn {string,...} lines
+local function split(blk)
+  local lines = {}
+  local i, nblk = 1, #blk
+  while i <= nblk do
+    local p, q, r, s = blk:find("([\r\n])([\r\n]?)", i)
+    if not p then
+      p = nblk + 1
+    end
+    lines[#lines + 1] = blk:sub(i, p - 1)
+    i = p + 1
+    if p < nblk and q > p and r ~= s then  -- handle Lua-style CRLF, LFCR
+      i = i + 1
+    end
+  end
+  return lines
+end
+
+--- Post-lexing processing, can work on lexer table output.
+function M.post_lex(toklist, seminfolist, toklnlist)
+  local lnow, sloc = 0, 0
+  local function chk(ln)        -- if a new line, count it as an SLOC
+    if ln > lnow then           -- new line # must be > old line #
+      sloc = sloc + 1; lnow = ln
+    end
+  end
+  for i = 1, #toklist do        -- enumerate over all tokens
+    local tok, info, ln
+      = toklist[i], seminfolist[i], toklnlist[i]
+
+    if tok == "TK_KEYWORD" or tok == "TK_NAME" or       -- significant
+       tok == "TK_NUMBER" or tok == "TK_OP" then
+      chk(ln)
+
+    -- Both TK_STRING and TK_LSTRING may be multi-line, hence, a loop
+    -- is needed in order to mark off lines one-by-one. Since llex.lua
+    -- currently returns the line number of the last part of the string,
+    -- we must subtract in order to get the starting line number.
+    elseif tok == "TK_STRING" then      -- possible multi-line
+      local t = split(info)
+      ln = ln - #t + 1
+      for _ = 1, #t do
+        chk(ln); ln = ln + 1
+      end
+
+    elseif tok == "TK_LSTRING" then     -- possible multi-line
+      local t = split(info)
+      ln = ln - #t + 1
+      for j = 1, #t do
+        if t[j] ~= "" then chk(ln) end
+        ln = ln + 1
+      end
+    -- Other tokens are comments or whitespace and are ignored.
+    end
+  end--for
+  print(srcfl..": "..sloc) -- display result
+  option.EXIT = true
+end
+
+return M

tools/luasrcdiet/utils.lua

@@ -0,0 +1,30 @@
+---------
+-- General utility functions.
+--
+-- **Note: This module is not part of public API!**
+----
+local ipairs = ipairs
+local pairs = pairs
+
+local M = {}
+
+--- Returns a new table containing the contents of all the given tables.
+-- Tables are iterated using @{pairs}, so this function is intended for tables
+-- that represent *associative arrays*. Entries with duplicate keys are
+-- overwritten with the values from a later table.
+--
+-- @tparam {table,...} ... The tables to merge.
+-- @treturn table A new table.
+function M.merge (...)
+  local result = {}
+
+  for _, tab in ipairs{...} do
+    for key, val in pairs(tab) do
+      result[key] = val
+    end
+  end
+
+  return result
+end
+
+return M

websrv_diet.lua

@@ -0,0 +1,270 @@
+local o="config.lua"
+local n=false
+local t=0
+function sendPage(o,e,i)
+collectgarbage()
+print("Sending "..e.." "..t.."B already; "..node.heap().."B in heap")
+o:on("sent",function(a)
+if(t==0)then
+a:close()
+print("Page sent")
+collectgarbage()
+n=false
+else
+collectgarbage()
+sendPage(a,e,i)
+end
+end)
+if file.open(e,"r")then
+local e=""
+if(t<=0)then
+e=e.."HTTP/1.1 200 OK\r\n"
+e=e.."Content-Type: text/html\r\n"
+e=e.."Connection: close\r\n"
+e=e.."Date: Thu, 29 Dec 2016 20:18:20 GMT\r\n"
+e=e.."\r\n\r\n"
+end
+file.seek("set",t)
+local a=file.readline()
+while(a~=nil)do
+if(a:find("$")~=nil)then
+if(i~=nil)then
+for e,t in pairs(i)
+do
+a=string.gsub(a,e,t)
+end
+end
+end
+t=t+string.len(a)
+e=e..a
+if((string.len(e)>=500)or(node.heap()<2000))then
+a=nil
+o:send(e)
+print("Sent part of "..t.."B")
+return
+else
+a=file.readline()
+end
+end
+t=0
+if(string.len(e)>0)then
+o:send(e)
+print("Sent rest")
+end
+end
+end
+function fillDynamicMap()
+replaceMap={}
+ssid,_=wifi.sta.getconfig()
+if(ssid==nil)then return replaceMap end
+if(sntpserverhostname==nil)then sntpserverhostname="ptbtime1.ptb.de"end
+if(timezoneoffset==nil)then timezoneoffset=1 end
+if(color==nil)then color=string.char(0,0,250)end
+if(color1==nil)then color1=color end
+if(color2==nil)then color2=color end
+if(color3==nil)then color3=color end
+if(color4==nil)then color4=color end
+if(colorBg==nil)then colorBg=string.char(0,0,0)end
+local t="#"..string.format("%02x",string.byte(color,2))..string.format("%02x",string.byte(color,1))..string.format("%02x",string.byte(color,3))
+local n="#"..string.format("%02x",string.byte(color1,2))..string.format("%02x",string.byte(color1,1))..string.format("%02x",string.byte(color1,3))
+local e="#"..string.format("%02x",string.byte(color2,2))..string.format("%02x",string.byte(color2,1))..string.format("%02x",string.byte(color2,3))
+local i="#"..string.format("%02x",string.byte(color3,2))..string.format("%02x",string.byte(color3,1))..string.format("%02x",string.byte(color3,3))
+local o="#"..string.format("%02x",string.byte(color4,2))..string.format("%02x",string.byte(color4,1))..string.format("%02x",string.byte(color4,3))
+local a="#"..string.format("%02x",string.byte(colorBg,2))..string.format("%02x",string.byte(colorBg,1))..string.format("%02x",string.byte(colorBg,3))
+replaceMap["$SSID"]=ssid
+replaceMap["$SNTPSERVER"]=sntpserverhostname
+replaceMap["$TIMEOFFSET"]=timezoneoffset
+replaceMap["$THREEQUATER"]=(threequater and"checked"or"")
+replaceMap["$ADDITIONAL_LINE"]=""
+replaceMap["$HEXCOLORFG"]=t
+replaceMap["$HEXCOLOR1"]=n
+replaceMap["$HEXCOLOR2"]=e
+replaceMap["$HEXCOLOR3"]=i
+replaceMap["$HEXCOLOR4"]=o
+replaceMap["$HEXCOLORBG"]=a
+replaceMap["$INV46"]=((inv46~=nil and inv46=="on")and"checked"or"")
+replaceMap["$AUTODIM"]=((dim~=nil and dim=="on")and"checked"or"")
+return replaceMap
+end
+function startWebServer()
+srv=net.createServer(net.TCP)
+srv:listen(80,function(i)
+i:on("receive",function(t,e)
+if(n)then
+print("HTTP sending... be patient!")
+return
+end
+if(e:find("GET /")~=nil)then
+n=true
+if(color==nil)then
+color=string.char(0,128,0)
+end
+ws2812.write(string.char(0,0,0):rep(56)..color:rep(2)..string.char(0,0,0):rep(4)..color:rep(2)..string.char(0,0,0):rep(48))
+if(sendPage~=nil)then
+print("Sending webpage.html ("..tostring(node.heap()).."B free) ...")
+replaceMap=fillDynamicMap()
+sendPage(t,"webpage.html",replaceMap)
+end
+else if(e:find("POST /")~=nil)then
+_,postdatastart=e:find("\r\n\r\n")
+if postdatastart==nil then postdatastart=1 end
+local a=string.sub(e,postdatastart+1)
+local e={}
+for t,a in string.gmatch(a,"(%w+)=([^&]+)&*")do
+e[t]=a
+end
+if(e.action~=nil and e.action=="Reboot")then
+node.restart()
+return
+end
+if((e.ssid~=nil)and(e.sntpserver~=nil)and(e.timezoneoffset~=nil))then
+print("New config!")
+if(e.password==nil)then
+_,password,_,_=wifi.sta.getconfig()
+print("Restoring password : "..password)
+e.password=password
+password=nil
+end
+file.remove(o..".new")
+sec,_=rtctime.get()
+file.open(o..".new","w+")
+file.write("-- Config\n".."station_cfg={}\nstation_cfg.ssid=\""..e.ssid.."\"\nstation_cfg.pwd=\""..e.password.."\"\nstation_cfg.save=false\nwifi.sta.config(station_cfg)\n")
+file.write("sntpserverhostname=\""..e.sntpserver.."\"\n".."timezoneoffset=\""..e.timezoneoffset.."\"\n".."inv46=\""..tostring(e.inv46).."\"\n".."dim=\""..tostring(e.dim).."\"\n")
+if(e.fcolor~=nil)then
+print("Got fcolor: "..e.fcolor)
+local e=string.sub(e.fcolor,4)
+local t=tonumber(string.sub(e,1,2),16)
+local a=tonumber(string.sub(e,3,4),16)
+local e=tonumber(string.sub(e,5,6),16)
+file.write("color=string.char("..a..","..t..","..e..")\n")
+color=string.char(a,t,e)
+end
+if(e.colorMin1~=nil)then
+local e=string.sub(e.colorMin1,4)
+local t=tonumber(string.sub(e,1,2),16)
+local a=tonumber(string.sub(e,3,4),16)
+local e=tonumber(string.sub(e,5,6),16)
+file.write("color1=string.char("..a..","..t..","..e..")\n")
+color1=string.char(a,t,e)
+end
+if(e.colorMin2~=nil)then
+local e=string.sub(e.colorMin2,4)
+local a=tonumber(string.sub(e,1,2),16)
+local t=tonumber(string.sub(e,3,4),16)
+local e=tonumber(string.sub(e,5,6),16)
+file.write("color2=string.char("..t..","..a..","..e..")\n")
+color2=string.char(t,a,e)
+end
+if(e.colorMin3~=nil)then
+local e=string.sub(e.colorMin3,4)
+local t=tonumber(string.sub(e,1,2),16)
+local a=tonumber(string.sub(e,3,4),16)
+local e=tonumber(string.sub(e,5,6),16)
+file.write("color3=string.char("..a..","..t..","..e..")\n")
+color3=string.char(a,t,e)
+end
+if(e.colorMin4~=nil)then
+local e=string.sub(e.colorMin4,4)
+local t=tonumber(string.sub(e,1,2),16)
+local a=tonumber(string.sub(e,3,4),16)
+local e=tonumber(string.sub(e,5,6),16)
+file.write("color4=string.char("..a..","..t..","..e..")\n")
+color4=string.char(a,t,e)
+end
+if(e.bcolor~=nil)then
+local e=string.sub(e.bcolor,4)
+local t=tonumber(string.sub(e,1,2),16)
+local a=tonumber(string.sub(e,3,4),16)
+local e=tonumber(string.sub(e,5,6),16)
+file.write("colorBg=string.char("..a..","..t..","..e..")\n")
+colorBg=string.char(a,t,e)
+end
+if(getTime~=nil)then
+time=getTime(sec,timezoneoffset)
+file.write("print(\"Config from "..time.year.."-"..time.month.."-"..time.day.." "..time.hour..":"..time.minute..":"..time.second.."\")\n")
+end
+if(e.threequater~=nil)then
+file.write("threequater=true\n")
+threequater=true
+else
+file.write("threequater=nil\n")
+threequater=nil
+end
+file.close()
+collectgarbage()
+sec=nil
+file.remove(o)
+print("Rename config")
+if(file.rename(o..".new",o))then
+print("Successfully")
+local e=tmr.create()
+e:register(50,tmr.ALARM_SINGLE,function(e)
+replaceMap=fillDynamicMap()
+replaceMap["$ADDITIONAL_LINE"]="<h2><font color=\"green\">New configuration saved</font></h2>"
+print("Send success to client")
+sendPage(t,"webpage.html",replaceMap)
+e:unregister()
+end)
+e:start()
+else
+local e=tmr.create()
+e:register(50,tmr.ALARM_SINGLE,function(e)
+replaceMap=fillDynamicMap()
+replaceMap["$ADDITIONAL_LINE"]="<h2><font color=\"red\">ERROR</font></h2>"
+sendPage(t,"webpage.html",replaceMap)
+e:unregister()
+end)
+e:start()
+end
+else
+replaceMap=fillDynamicMap()
+replaceMap["$ADDITIONAL_LINE"]="<h2><font color=\"orange\">Not all parameters set</font></h2>"
+sendPage(t,"webpage.html",replaceMap)
+end
+else
+print("Hello via telnet")
+global_c=t
+function s_output(e)
+if(global_c~=nil)
+then global_c:send(e)
+end
+end
+node.output(s_output,0)
+global_c:on("receive",function(t,e)
+node.input(e)
+end)
+global_c:on("disconnection",function(e)
+node.output(nil)
+global_c=nil
+end)
+print("Welcome to Word Clock")
+end
+end
+end)
+i:on("disconnection",function(e)
+print("Goodbye")
+node.output(nil)
+collectgarbage()
+t=0
+end)
+end)
+end
+function startSetupMode()
+collectgarbage()
+wifi.setmode(wifi.SOFTAP)
+cfg={}
+cfg.ssid="wordclock"
+cfg.pwd="wordclock"
+wifi.ap.config(cfg)
+local t=string.char(0,128,0)
+local e=string.char(0,0,0)
+local a=e:rep(6)..t..e:rep(7)..t:rep(3)..e:rep(44)..t:rep(3)..e:rep(50)
+ws2812.write(a)
+t=nil
+e=nil
+a=nil
+print("Waiting in access point >wordclock< for Clients")
+print("Please visit 192.168.4.1")
+startWebServer()
+collectgarbage()
+end