OC-KittenOS/inst/build.lua

-- Copyright (C) 2018-2021 by KittenOS NEO contributors
--
-- Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted.
--
-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
-- THIS SOFTWARE.

-- KittenOS NEO Installer Generator --
local args = {...}

local cid = args[1]
local tarName = args[2]
local algorithmsInReverseOrder = {}
for i = 3, #args do
 table.insert(algorithmsInReverseOrder, 1, args[i])
end

local u = require("libs.frw")

local instSize = 0
local function put(data)
 io.write(data)
 instSize = instSize + #data
end

-- Installer Lexcrunch Context --
local lexCrunch = require("libs.lexcrunch")()

-- Installer Core --

-- installerFinalized:
--  Stuff that's already finished and put at the end of RISM. Prepend to this.
-- installerPayload / installerProgramLength:
--  The next-outer chunk that hasn't been written to the end of RISM
--   as the compression scheme (if one) has not been applied yet.
--  Really, installerProgramLength is only necessary because of the innermost chunk,
--   as that chunk has the TAR; additional data that's part of the same effective compression block,
--   but requires the program length to avoid it.
local installerPayload
local installerProgramLength
local installerFinalized = ""

do
 local tarData = u.read(tarName)
 local tarSectors = math.floor(#tarData / 512)
 local installerCore = lexCrunch.process(u.read("instcore.lua"), {["$$SECTORS"] = tostring(tarSectors)})
 installerPayload = installerCore .. tarData
 installerProgramLength = #installerCore
end

-- Installer Compression --
for _, v in ipairs(algorithmsInReverseOrder) do
 io.stderr:write("compressing (" .. v .. ")\n")
 local algImpl = require(v .. ".compress")
 local algEngine, algData = algImpl(installerPayload, lexCrunch)
 io.stderr:write("result: " .. #installerPayload .. " -> " .. #algData .. "\n")
 -- prepend the program length of the last section
 algEngine = lexCrunch.process("$iBlockingLen = " .. installerProgramLength .. " " .. algEngine, {})
 -- commit
 installerPayload = algEngine
 installerProgramLength = #installerPayload
 installerFinalized = algData .. installerFinalized
end

-- Installer Final --

-- This is a special case, so the program length/payload/etc. business has to be repeated.
put("--" .. cid .. "\n")
put("--This is released into the public domain. No warranty is provided, implied or otherwise.\n")
put(lexCrunch.process(u.read("insthead.lua"), {["$$CORESIZE"] = tostring(installerProgramLength)}))

local RISM = installerPayload .. installerFinalized
RISM = RISM:gsub("\xFE", "\xFE\xFE")
RISM = RISM:gsub("]]", "]\xFE]")
RISM = "\x00" .. RISM
put("--[[" .. RISM .. "]]")

-- Dumping debug info --
local dbg = io.open("iSymTab", "wb")
lexCrunch.dump(dbg)
dbg:close()