74 lines
1.8 KiB
Go
74 lines
1.8 KiB
Go
/*
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Copyright The containerd 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 continuity
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import (
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"fmt"
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"os"
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)
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var (
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errNotAHardLink = fmt.Errorf("invalid hardlink")
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)
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type hardlinkManager struct {
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hardlinks map[hardlinkKey][]Resource
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}
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func newHardlinkManager() *hardlinkManager {
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return &hardlinkManager{
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hardlinks: map[hardlinkKey][]Resource{},
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}
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}
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// Add attempts to add the resource to the hardlink manager. If the resource
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// cannot be considered as a hardlink candidate, errNotAHardLink is returned.
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func (hlm *hardlinkManager) Add(fi os.FileInfo, resource Resource) error {
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if _, ok := resource.(Hardlinkable); !ok {
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return errNotAHardLink
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}
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key, err := newHardlinkKey(fi)
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if err != nil {
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return err
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}
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hlm.hardlinks[key] = append(hlm.hardlinks[key], resource)
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return nil
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}
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// Merge processes the current state of the hardlink manager and merges any
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// shared nodes into hard linked resources.
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func (hlm *hardlinkManager) Merge() ([]Resource, error) {
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var resources []Resource
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for key, linked := range hlm.hardlinks {
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if len(linked) < 1 {
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return nil, fmt.Errorf("no hardlink entrys for dev, inode pair: %#v", key)
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}
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merged, err := Merge(linked...)
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if err != nil {
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return nil, fmt.Errorf("error merging hardlink: %v", err)
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}
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resources = append(resources, merged)
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}
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return resources, nil
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}
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