wasmdump.lua

#!/usr/bin/lua
if not arg or not arg[1] or arg[1] == "" or not arg[2] or arg[2] == "" then
    print("Usage: ./wasmdump.lua FILE OUTPUTDIR")
    return
end

local inputpath = arg[1]
local outputpath = arg[2]:gsub("/$", "")

local f = io.open(inputpath, "r")
if not f then
    print("Failed to open file")
    return
end

local d = f:read("*a")
f:close()

if not d then
    print("Failed to read file")
    return
end

for s in d:gmatch('%(data ?%(i32.const %d+%)[\n\t ]*".-"[\n\t ]*%)') do
    local id = s:match('%(data ?%(i32.const (%d+)%)')
    print("Dumping "..id)
    local d2 = s:match('"(.-)"')
    d2 = d2:gsub('\\%x%x', function(s)
        return string.char(tonumber(s:sub(2), 16))
    end)
    local f = io.open(outputpath.."/"..id..".dat", "w+")
    if not f then
        print("Failed to open file")
        return
    end
    f:write(d2)
    f:close()
end