added the preproc library, meaning PsychOS is nominally self-hosting

This commit is contained in:
Izaya 2020-06-03 09:55:22 +10:00
parent 7dda36fd1d
commit 29cdcb1809
4 changed files with 74 additions and 1 deletions

3
build.lua Normal file
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local preproc = require "preproc"
--local tA = {...}
preproc(...)

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LUA=${LUA:-lua}
rm -r target/*
mkdir -p target/doc &>/dev/null
$LUA luapreproc.lua module/init.lua target/init.lua
$LUA build.lua module/init.lua target/init.lua
echo _OSVERSION=\"PsychOS 2.0a2-$(git rev-parse --short HEAD)\" > target/version.lua
cat target/version.lua target/init.lua > target/tinit.lua
mv target/tinit.lua target/init.lua

69
lib/preproc.lua Normal file
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local preproc = {}
preproc.directives = {}
function preproc.parsewords(line) -- string -- table -- Returns a table of words from the string *line*, parsing quotes and escapes.
local rt = {""}
local escaped, quoted = false, false
for c in line:gmatch(".") do
if escaped then
rt[#rt] = rt[#rt]..c
elseif c == '"' or c == "'" then
quoted = not quoted
elseif c == "\\" then
escaped = true
elseif c:match("%s") and not quoted and rt[#rt]:len() > 0 then
rt[#rt+1] = ""
else
rt[#rt] = rt[#rt]..c
end
end
return rt
end
function preproc.line(line) -- string -- -- Returns either a function - which can be called to get lines until it returns nil - or a string from processing *line* using preprocessor directives.
if line:match("^%-%-#") then
local directive, args = line:match("^%-%-#(%S+)%s(.+)")
print(directive,args)
local args = preproc.parsewords(args)
if preproc.directives[directive] then
return preproc.directives[directive](table.unpack(args))
else
error("unknown preprocessor directive: "..directive)
end
else
return line
end
end
function preproc.preproc(...) -- string -- string -- Returns the output from preprocessing the files listed in *...*.
local tA = {...}
local output = ""
for _,fname in ipairs(tA) do
local f,e = io.open(fname)
if not f then error("unable to open file "..fname..": "..e) end
for line in f:lines() do
local r = preproc.line(line)
if type(r) == "function" then
while true do
local rs = r()
if not rs then break end
output = output .. rs .. "\n"
end
else
output = output .. r .. "\n"
end
end
end
return output
end
preproc.directives.include = preproc.preproc
return setmetatable(preproc,{__call=function(_,...)
local tA = {...}
local out = table.remove(tA,#tA)
local f,e = io.open(out,"wb")
if not f then error("unable to open file "..out..": "..e) end
f:write(preproc.preproc(table.unpack(tA)))
f:close()
end})

1
preproc.lua Symbolic link
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lib/preproc.lua