66 lines
1.1 KiB
Go
66 lines
1.1 KiB
Go
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package cache
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import (
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"code.google.com/p/goprotobuf/proto"
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bin "encoding/binary"
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"sync"
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)
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type RefIndex struct {
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Cache
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mu sync.Mutex
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}
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func NewRefIndex(path string) (*RefIndex, error) {
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index := RefIndex{}
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err := index.open(path)
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if err != nil {
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return nil, err
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}
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return &index, nil
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}
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func (index *RefIndex) Add(id, ref int64) error {
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keyBuf := make([]byte, 8)
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bin.PutVarint(keyBuf, id)
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data, err := index.db.Get(index.ro, keyBuf)
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if err != nil {
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panic(err)
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}
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refs := &Refs{}
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if data != nil {
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err = proto.Unmarshal(data, refs)
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if err != nil {
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panic(err)
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}
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}
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if refs.Ids == nil {
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refs.Ids = make([]int64, 0, 1)
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}
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// TODO change to delta encoding
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// TODO check for duplicates
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refs.Ids = append(refs.Ids, ref)
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data, err = proto.Marshal(refs)
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if err != nil {
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panic(err)
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}
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err = index.db.Put(index.wo, keyBuf, data)
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return err
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}
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func (index *RefIndex) Get(id int64) []int64 {
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keyBuf := make([]byte, 8)
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bin.PutVarint(keyBuf, id)
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data, err := index.db.Get(index.ro, keyBuf)
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refs := &Refs{}
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if data != nil {
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err = proto.Unmarshal(data, refs)
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if err != nil {
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panic(err)
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}
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}
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return refs.Ids
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}
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