errno_windows.mx raw

   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  //go:build windows
   6  
   7  package poll
   8  
   9  import "syscall"
  10  
  11  // Do the interface allocations only once for common
  12  // Errno values.
  13  
  14  var (
  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.
  20  func 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