A Lua script to embed Lua code in a C module.

foo.c

#include <lua.h>
#include <lauxlib.h>
#include <lualib.h>
#ifdef WIN32
#define EXPORT __declspec(dllexport)
#else
#define EXPORT
#endif

static const char * lua_code = \
"module 'foo'\n"\
"\n"\
"function answer()\n"\
"return 42\n"\
"end\n";

EXPORT int luaopen_foo (lua_State *L) {
    luaL_dostring(L,lua_code);
    return 1;
}

lua2c.lua

-- lua2c.lua

function quit (msg)
    io.stderr:write(msg,'\n')
    os.exit(1)
end

function massage_path (name)
    return (name:gsub('%.','/'))
end

function massage_name (name)
    return (name:gsub('%.','_'))
end


local skeleton = [[
#include <lua.h>
#include <lauxlib.h>
#include <lualib.h>
#ifdef WIN32
#define EXPORT __declspec(dllexport)
#else
#define EXPORT
#endif

$CODE;

EXPORT int luaopen_$NAME (lua_State *L) {
    luaL_dostring(L,lua_code);
    return 1;
}
]]

local name = arg[1] or quit 'must provide name of module'
local file = massage_path(name) .. '.lua'
local f,e = io.open(file,'r')
if not f then quit (e) end

local out, append = {}, table.insert
append(out,'static const char * lua_code = ')
for line in f:lines() do
    -- all non-blank, non-comment lines
    if not line:match '^%s*%-%-' or line:match '^%s*$' then
        line = line:gsub('^%s*',''):gsub('\\','\\\\'):gsub('"','\\"')
        line = '"'..line..'\\n"'
        append(out,line)
    end
end
f:close()
out = table.concat(out,'\\\n')
local output = skeleton:gsub('%$(%u+)',{
    CODE = out,
    NAME = massage_name(name)
})
f = io.open(massage_path(name)..'.c','w')
f:write(output)
f:close()