1// Copyright 2019 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5// +build windows
6
7package poll
8
9import "syscall"
10
11// Do the interface allocations only once for common
12// Errno values.
13
14var (
15	errERROR_IO_PENDING error = syscall.Errno(syscall.ERROR_IO_PENDING)
16)
17
18// ErrnoErr returns common boxed Errno values, to prevent
19// allocations at runtime.
20func errnoErr(e syscall.Errno) error {
21	switch e {
22	case 0:
23		return nil
24	case syscall.ERROR_IO_PENDING:
25		return errERROR_IO_PENDING
26	}
27	// TODO: add more here, after collecting data on the common
28	// error values see on Windows. (perhaps when running
29	// all.bat?)
30	return e
31}
32