forked from TrueCloudLab/restic
69 lines
955 B
Go
69 lines
955 B
Go
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package backend
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import (
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"errors"
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"sort"
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"sync"
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)
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type IDSet struct {
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list IDs
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m sync.Mutex
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}
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func NewIDSet() *IDSet {
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return &IDSet{
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list: make(IDs, 0),
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}
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}
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func (s *IDSet) find(id ID) (int, error) {
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pos := sort.Search(len(s.list), func(i int) bool {
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return id.Compare(s.list[i]) >= 0
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})
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if pos < len(s.list) {
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candID := s.list[pos]
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if id.Compare(candID) == 0 {
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return pos, nil
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}
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}
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return pos, errors.New("ID not found")
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}
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func (s *IDSet) insert(id ID) {
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pos, err := s.find(id)
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if err == nil {
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// already present
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return
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}
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// insert blob
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// https://code.google.com/p/go-wiki/wiki/SliceTricks
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s.list = append(s.list, ID{})
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copy(s.list[pos+1:], s.list[pos:])
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s.list[pos] = id
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return
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}
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func (s *IDSet) Insert(id ID) {
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s.m.Lock()
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defer s.m.Unlock()
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s.insert(id)
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}
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func (s *IDSet) Find(id ID) error {
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s.m.Lock()
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defer s.m.Unlock()
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_, err := s.find(id)
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if err != nil {
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return err
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}
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return nil
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}
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