package main

import (
	"io/ioutil"
	"net"
	"os"

	"gitlab.com/gitlab-org/labkit/errortracking"
)

func readFile(file string) (result []byte) {
	result, err := ioutil.ReadFile(file)
	if err != nil {
		fatal(err, "could not read file")
	}
	return
}

// Be careful: if you let either of the return values get garbage
// collected by Go they will be closed automatically.
func createSocket(addr string) (net.Listener, *os.File) {
	l, err := net.Listen("tcp", addr)
	if err != nil {
		fatal(err, "could not create socket")
	}

	return l, fileForListener(l)
}

func fileForListener(l net.Listener) *os.File {
	type filer interface {
		File() (*os.File, error)
	}

	f, err := l.(filer).File()
	if err != nil {
		fatal(err, "could not find file for listener")
	}

	return f
}

func capturingFatal(err error, fields ...errortracking.CaptureOption) {
	errortracking.Capture(err, fields...)
	fatal(err, "capturing fatal")
}