wg-quicker/vendor/github.com/mdlayher/netlink/errors.go

129 lines
3.5 KiB
Go

package netlink
import (
"errors"
"fmt"
"net"
"os"
)
// Error messages which can be returned by Validate.
var (
errMismatchedSequence = errors.New("mismatched sequence in netlink reply")
errMismatchedPID = errors.New("mismatched PID in netlink reply")
errShortErrorMessage = errors.New("not enough data for netlink error code")
)
// Errors which can be returned by a Socket that does not implement
// all exposed methods of Conn.
var errNotSupported = errors.New("operation not supported")
// notSupported provides a concise constructor for "not supported" errors.
func notSupported(op string) error {
return newOpError(op, errNotSupported)
}
// IsNotExist determines if an error is produced as the result of querying some
// file, object, resource, etc. which does not exist. Users of this package
// should always use netlink.IsNotExist, rather than os.IsNotExist, when
// checking for specific netlink-related errors.
//
// Errors types created by this package, such as OpError, can be used with
// IsNotExist, but this function also defers to the behavior of os.IsNotExist
// for unrecognized error types.
//
// Deprecated: make use of errors.Unwrap and errors.Is in Go 1.13+.
func IsNotExist(err error) bool {
switch err := err.(type) {
case *OpError:
// TODO(mdlayher): more error handling logic?
// Unwrap the inner error and use the stdlib's logic.
return os.IsNotExist(err.Err)
default:
return os.IsNotExist(err)
}
}
var (
_ error = &OpError{}
_ net.Error = &OpError{}
// Ensure compatibility with Go 1.13+ errors package.
_ interface{ Unwrap() error } = &OpError{}
)
// An OpError is an error produced as the result of a failed netlink operation.
type OpError struct {
// Op is the operation which caused this OpError, such as "send"
// or "receive".
Op string
// Err is the underlying error which caused this OpError.
//
// If Err was produced by a system call error, Err will be of type
// *os.SyscallError. If Err was produced by an error code in a netlink
// message, Err will contain a raw error value type such as a unix.Errno.
//
// Most callers should inspect Err using a helper such as IsNotExist.
Err error
}
// newOpError is a small wrapper for creating an OpError. As a convenience, it
// returns nil if the input err is nil: akin to os.NewSyscallError.
func newOpError(op string, err error) error {
if err == nil {
return nil
}
return &OpError{
Op: op,
Err: err,
}
}
func (e *OpError) Error() string {
if e == nil {
return "<nil>"
}
return fmt.Sprintf("netlink %s: %v", e.Op, e.Err)
}
// Unwrap unwraps the internal Err field for use with errors.Unwrap.
func (e *OpError) Unwrap() error { return e.Err }
// Portions of this code taken from the Go standard library:
//
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
type timeout interface {
Timeout() bool
}
// Timeout reports whether the error was caused by an I/O timeout.
func (e *OpError) Timeout() bool {
if ne, ok := e.Err.(*os.SyscallError); ok {
t, ok := ne.Err.(timeout)
return ok && t.Timeout()
}
t, ok := e.Err.(timeout)
return ok && t.Timeout()
}
type temporary interface {
Temporary() bool
}
// Temporary reports whether an operation may succeed if retried.
func (e *OpError) Temporary() bool {
if ne, ok := e.Err.(*os.SyscallError); ok {
t, ok := ne.Err.(temporary)
return ok && t.Temporary()
}
t, ok := e.Err.(temporary)
return ok && t.Temporary()
}