Re: Embedding Lua bytecode in C binary

["Mildred Ki'Lya" <ml.mildred593@...>]

Hi,

Well, doing that is fairly simple. Recently, i had to create a binary
that would just invoke an internal lua script to do the job. I ended up
recreating bin2c:

---------- bin2c.lua ----------
local name, static = ...

name = name or "stdin"
static = static or ""

local out = { static, " ", "char ", name, "[] = {\n  " }
if static == '' then
  out[2] = ''
end

local len = 0
local c = io.read(1)
local l = 2;
while c do
  len = len + 1
  if l + 7 > 80 then
    out[#out] = ",\n  ";
    l = 2
  end
  out[#out+1] = ("0x%02x"):format(c:byte())
  out[#out+1] = ", "
  l = l + 6
  c = io.read(1)
end
out[#out] = " };\n\n";
out[#out+1] = "int "
out[#out+1] = name
out[#out+1] = "_size = "
out[#out+1] = tostring(len)
out[#out+1] = ";\n\n"

io.write(table.concat(out))

-------------------------------


Just invoke it that way:

	lua bin2c.lua c_symbol [static] <input_file.lua >output_file.c

(if you add the optional static parameter, the byte array will be
declared static)

In your C file, you'll then be able to:

	#include "output_file.c"

	int err_code = luaL_loadbuffer(L, c_symbol, c_symbol_size, "input_file.lua");


That's really simple.

The only drawback is that require() would work like any script. So if
you use some modules, you'll have to include them as well (i guess
you'll need to put them in package.preload in the C code). But for what
I wanted to do, that wasn't necessary.



Mildred

-- 
Mildred Ki'Lya
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