mirror of https://github.com/k3s-io/k3s
79 lines
2.1 KiB
Go
79 lines
2.1 KiB
Go
/*
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Copyright 2017 The Kubernetes Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package path
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import (
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"errors"
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"os"
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)
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// LinkTreatment is the base type for constants used by Exists that indicate
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// how symlinks are treated for existence checks.
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type LinkTreatment int
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const (
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// CheckFollowSymlink follows the symlink and verifies that the target of
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// the symlink exists.
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CheckFollowSymlink LinkTreatment = iota
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// CheckSymlinkOnly does not follow the symlink and verifies only that they
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// symlink itself exists.
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CheckSymlinkOnly
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)
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// ErrInvalidLinkTreatment indicates that the link treatment behavior requested
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// is not a valid behavior.
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var ErrInvalidLinkTreatment = errors.New("unknown link behavior")
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// Exists checks if specified file, directory, or symlink exists. The behavior
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// of the test depends on the linkBehaviour argument. See LinkTreatment for
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// more details.
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func Exists(linkBehavior LinkTreatment, filename string) (bool, error) {
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var err error
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if linkBehavior == CheckFollowSymlink {
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_, err = os.Stat(filename)
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} else if linkBehavior == CheckSymlinkOnly {
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_, err = os.Lstat(filename)
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} else {
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return false, ErrInvalidLinkTreatment
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}
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if os.IsNotExist(err) {
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return false, nil
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} else if err != nil {
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return false, err
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}
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return true, nil
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}
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// ReadDirNoStat returns a string of files/directories contained
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// in dirname without calling lstat on them.
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func ReadDirNoStat(dirname string) ([]string, error) {
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if dirname == "" {
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dirname = "."
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}
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f, err := os.Open(dirname)
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if err != nil {
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return nil, err
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}
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defer f.Close()
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return f.Readdirnames(-1)
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}
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