package main

import (
	"encoding/binary"
	"runtime"
	"testing"
	"unsafe"
)

// Keep each recursive frame live so the stack must grow past its initial allocation.
//
//go:noinline
func growStack(depth byte) byte {
	var frame [4096]byte
	frame[0] = depth
	if depth > 0 {
		frame[1] = growStack(depth - 1)
	}
	runtime.KeepAlive(&frame)
	return frame[0] + frame[1]
}

func TestPinnedRequest(t *testing.T) {
	if unsafe.Sizeof(tableInfo{}) != 84 {
		t.Fatal("native getsockopt layout differs from ipt_getinfo")
	}
	done := make(chan [2]uint64, 1)
	go func() {
		request := newReplace(config{inbound: 4143, outbound: 4140}, 5)
		defer request.pins.Unpin()
		growStack(32)
		runtime.GC()
		done <- [2]uint64{binary.NativeEndian.Uint64(request.data[88:]), request.address()}
	}()
	addresses := <-done
	if addresses[0] != addresses[1] {
		t.Fatalf("counter address moved: %x -> %x", addresses[0], addresses[1])
	}
}