libgo/go/os/error.go

   1 // Copyright 2009 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 package os
   6
   7 import (
   8         "errors"
   9 )
  10
  11 // Portable analogs of some common system call errors.
  12 var (
  13         ErrInvalid    = errors.New("invalid argument")
  14         ErrPermission = errors.New("permission denied")
  15         ErrExist      = errors.New("file already exists")
  16         ErrNotExist   = errors.New("file does not exist")
  17 )
  18
  19 // PathError records an error and the operation and file path that caused it.
  20 type PathError struct {
  21         Op   string
  22         Path string
  23         Err  error
  24 }
  25
  26 func (e *PathError) Error() string { return e.Op + " " + e.Path + ": " + e.Err.Error() }
  27
  28 // SyscallError records an error from a specific system call.
  29 type SyscallError struct {
  30         Syscall string
  31         Err     error
  32 }
  33
  34 func (e *SyscallError) Error() string { return e.Syscall + ": " + e.Err.Error() }
  35
  36 // NewSyscallError returns, as an error, a new SyscallError
  37 // with the given system call name and error details.
  38 // As a convenience, if err is nil, NewSyscallError returns nil.
  39 func NewSyscallError(syscall string, err error) error {
  40         if err == nil {
  41                 return nil
  42         }
  43         return &SyscallError{syscall, err}
  44 }
  45
  46 // IsExist returns a boolean indicating whether the error is known to report
  47 // that a file or directory already exists. It is satisfied by ErrExist as
  48 // well as some syscall errors.
  49 func IsExist(err error) bool {
  50         return isExist(err)
  51 }
  52
  53 // IsNotExist returns a boolean indicating whether the error is known to
  54 // report that a file or directory does not exist. It is satisfied by
  55 // ErrNotExist as well as some syscall errors.
  56 func IsNotExist(err error) bool {
  57         return isNotExist(err)
  58 }
  59
  60 // IsPermission returns a boolean indicating whether the error is known to
  61 // report that permission is denied. It is satisfied by ErrPermission as well
  62 // as some syscall errors.
  63 func IsPermission(err error) bool {
  64         return isPermission(err)
  65 }