func GetTableInt(L *lua.State, name string) int {
// Remember to check stack for 1 extra location
L.PushString(name)
L.GetTable(-2)
r := L.ToInteger(-1)
L.Pop(1)
return r
}
// Registers a Go function as a global variable and add it to the sandbox.
func sandboxRegister(L *lua.State, name string, f interface{}) {
goToLua(L, name, f)
L.PushString(registryWhitelist)
L.GetTable(lua.LUA_REGISTRYINDEX)
L.GetGlobal(name)
L.SetField(-2, name)
}
func ipairsAux(L *lua.State) int {
i := L.CheckInteger(2) + 1
L.PushInteger(int64(i))
L.PushInteger(int64(i))
L.GetTable(1)
if L.Type(-1) == lua.LUA_TNIL {
return 1
}
return 2
}
func LuaTableGetString(L *lua.State, key string) string {
L.PushString(key)
L.GetTable(-2)
r := ""
if !L.IsNil(-1) {
r = L.ToString(-1)
}
L.Pop(1)
return r
}
func sandboxCompile(L *lua.State, registryIndex string, name, code string) {
L.PushString(registryIndex)
L.GetTable(lua.LUA_REGISTRYINDEX)
L.PushString(name)
err := L.LoadString(code)
if err != 0 {
log.Fatalf("%s: %s", name, L.ToString(-1))
L.Pop(2)
} else {
L.SetTable(-3)
}
}
// 'exist' is optional.
func run(L *lua.State, registryIndex string, code string, input *inputInfo, output *outputInfo, exist *inputInfo) error {
// Restore the sandbox.
err := L.DoString(luaRestoreSandbox)
if err != nil {
log.Fatal("Cannot load function to restore sandbox", err)
}
L.PushString(registryWhitelist)
L.GetTable(lua.LUA_REGISTRYINDEX)
err = L.Call(1, 0)
if err != nil {
log.Fatal("Failed to restore sandbox", err)
}
goToLua(L, "input", *input)
goToLua(L, "output", *output)
if exist != nil {
goToLua(L, "existinfo", *exist)
}
// Shortcut (mostly for prescript and postscript).
L.GetGlobal("input")
L.GetField(-1, "tags")
L.SetGlobal("i")
L.Pop(1)
L.GetGlobal("output")
L.GetField(-1, "tags")
L.SetGlobal("o")
L.Pop(1)
// Call the compiled script.
L.PushString(registryIndex)
L.GetTable(lua.LUA_REGISTRYINDEX)
L.PushString(code)
if L.IsTable(-2) {
L.GetTable(-2)
if L.IsFunction(-1) {
err := L.Call(0, 0)
if err != nil {
L.SetTop(0)
return fmt.Errorf("%s", err)
}
} else {
L.Pop(1)
}
} else {
L.Pop(1)
}
L.Pop(1)
// Allow tags to be numbers for convenience.
outputNumbersToStrings(L)
L.GetGlobal("output")
r := luar.LuaToGo(L, reflect.TypeOf(*output), -1)
L.Pop(1)
*output = r.(outputInfo)
return nil
}
