forked from mirror/ledisdb
795 lines
14 KiB
Go
795 lines
14 KiB
Go
package ledis
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import (
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"encoding/binary"
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"errors"
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"fmt"
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"strings"
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"time"
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"github.com/siddontang/go/num"
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"github.com/siddontang/ledisdb/store"
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)
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// KVPair is the pair of key-value.
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type KVPair struct {
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Key []byte
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Value []byte
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}
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var errKVKey = errors.New("invalid encode kv key")
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func checkKeySize(key []byte) error {
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if len(key) > MaxKeySize || len(key) == 0 {
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return errKeySize
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}
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return nil
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}
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func checkValueSize(value []byte) error {
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if len(value) > MaxValueSize {
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return errValueSize
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}
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return nil
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}
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func (db *DB) encodeKVKey(key []byte) []byte {
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ek := make([]byte, len(key)+1+len(db.indexVarBuf))
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pos := copy(ek, db.indexVarBuf)
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ek[pos] = KVType
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pos++
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copy(ek[pos:], key)
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return ek
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}
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func (db *DB) decodeKVKey(ek []byte) ([]byte, error) {
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pos, err := db.checkKeyIndex(ek)
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if err != nil {
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return nil, err
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}
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if pos+1 > len(ek) || ek[pos] != KVType {
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return nil, errKVKey
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}
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pos++
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return ek[pos:], nil
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}
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func (db *DB) encodeKVMinKey() []byte {
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ek := db.encodeKVKey(nil)
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return ek
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}
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func (db *DB) encodeKVMaxKey() []byte {
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ek := db.encodeKVKey(nil)
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ek[len(ek)-1] = KVType + 1
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return ek
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}
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func (db *DB) incr(key []byte, delta int64) (int64, error) {
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if err := checkKeySize(key); err != nil {
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return 0, err
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}
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var err error
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key = db.encodeKVKey(key)
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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var n int64
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n, err = StrInt64(db.bucket.Get(key))
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if err != nil {
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return 0, err
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}
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n += delta
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t.Put(key, num.FormatInt64ToSlice(n))
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err = t.Commit()
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return n, err
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}
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// ps : here just focus on deleting the key-value data,
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// any other likes expire is ignore.
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func (db *DB) delete(t *batch, key []byte) int64 {
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key = db.encodeKVKey(key)
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t.Delete(key)
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return 1
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}
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func (db *DB) setExpireAt(key []byte, when int64) (int64, error) {
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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if exist, err := db.Exists(key); err != nil || exist == 0 {
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return 0, err
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}
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db.expireAt(t, KVType, key, when)
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if err := t.Commit(); err != nil {
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return 0, err
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}
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return 1, nil
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}
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// Decr decreases the data.
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func (db *DB) Decr(key []byte) (int64, error) {
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return db.incr(key, -1)
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}
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// DecrBy decreases the data by decrement.
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func (db *DB) DecrBy(key []byte, decrement int64) (int64, error) {
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return db.incr(key, -decrement)
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}
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// Del deletes the data.
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func (db *DB) Del(keys ...[]byte) (int64, error) {
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if len(keys) == 0 {
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return 0, nil
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}
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codedKeys := make([][]byte, len(keys))
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for i, k := range keys {
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codedKeys[i] = db.encodeKVKey(k)
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}
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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for i, k := range keys {
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t.Delete(codedKeys[i])
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db.rmExpire(t, KVType, k)
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}
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err := t.Commit()
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return int64(len(keys)), err
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}
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// Exists check data exists or not.
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func (db *DB) Exists(key []byte) (int64, error) {
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if err := checkKeySize(key); err != nil {
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return 0, err
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}
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var err error
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key = db.encodeKVKey(key)
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var v []byte
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v, err = db.bucket.Get(key)
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if v != nil && err == nil {
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return 1, nil
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}
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return 0, err
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}
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// Get gets the value.
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func (db *DB) Get(key []byte) ([]byte, error) {
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if err := checkKeySize(key); err != nil {
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return nil, err
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}
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key = db.encodeKVKey(key)
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return db.bucket.Get(key)
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}
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// GetSlice gets the slice of the data.
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func (db *DB) GetSlice(key []byte) (store.Slice, error) {
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if err := checkKeySize(key); err != nil {
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return nil, err
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}
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key = db.encodeKVKey(key)
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return db.bucket.GetSlice(key)
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}
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// GetSet gets the value and sets new value.
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func (db *DB) GetSet(key []byte, value []byte) ([]byte, error) {
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if err := checkKeySize(key); err != nil {
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return nil, err
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} else if err := checkValueSize(value); err != nil {
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return nil, err
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}
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key = db.encodeKVKey(key)
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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oldValue, err := db.bucket.Get(key)
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if err != nil {
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return nil, err
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}
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t.Put(key, value)
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err = t.Commit()
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return oldValue, err
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}
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// Incr increases the data.
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func (db *DB) Incr(key []byte) (int64, error) {
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return db.incr(key, 1)
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}
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// IncrBy increases the data by increment.
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func (db *DB) IncrBy(key []byte, increment int64) (int64, error) {
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return db.incr(key, increment)
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}
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// MGet gets multi data.
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func (db *DB) MGet(keys ...[]byte) ([][]byte, error) {
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values := make([][]byte, len(keys))
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it := db.bucket.NewIterator()
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defer it.Close()
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for i := range keys {
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if err := checkKeySize(keys[i]); err != nil {
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return nil, err
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}
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values[i] = it.Find(db.encodeKVKey(keys[i]))
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}
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return values, nil
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}
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// MSet sets multi data.
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func (db *DB) MSet(args ...KVPair) error {
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if len(args) == 0 {
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return nil
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}
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t := db.kvBatch
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var err error
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var key []byte
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var value []byte
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t.Lock()
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defer t.Unlock()
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for i := 0; i < len(args); i++ {
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if err := checkKeySize(args[i].Key); err != nil {
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return err
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} else if err := checkValueSize(args[i].Value); err != nil {
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return err
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}
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key = db.encodeKVKey(args[i].Key)
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value = args[i].Value
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t.Put(key, value)
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}
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err = t.Commit()
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return err
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}
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// Set sets the data.
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func (db *DB) Set(key []byte, value []byte) error {
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if err := checkKeySize(key); err != nil {
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return err
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} else if err := checkValueSize(value); err != nil {
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return err
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}
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var err error
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key = db.encodeKVKey(key)
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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t.Put(key, value)
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err = t.Commit()
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return err
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}
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// SetNX sets the data if not existed.
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func (db *DB) SetNX(key []byte, value []byte) (int64, error) {
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if err := checkKeySize(key); err != nil {
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return 0, err
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} else if err := checkValueSize(value); err != nil {
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return 0, err
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}
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var err error
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key = db.encodeKVKey(key)
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var n int64 = 1
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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if v, err := db.bucket.Get(key); err != nil {
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return 0, err
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} else if v != nil {
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n = 0
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} else {
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t.Put(key, value)
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err = t.Commit()
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}
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return n, err
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}
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// SetEX sets the data with a TTL.
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func (db *DB) SetEX(key []byte, duration int64, value []byte) error {
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if err := checkKeySize(key); err != nil {
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return err
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} else if err := checkValueSize(value); err != nil {
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return err
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} else if duration <= 0 {
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return errExpireValue
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}
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ek := db.encodeKVKey(key)
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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t.Put(ek, value)
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db.expireAt(t, KVType, key, time.Now().Unix()+duration)
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return t.Commit()
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}
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func (db *DB) flush() (drop int64, err error) {
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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return db.flushType(t, KVType)
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}
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// Expire expires the data.
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func (db *DB) Expire(key []byte, duration int64) (int64, error) {
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if duration <= 0 {
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return 0, errExpireValue
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}
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return db.setExpireAt(key, time.Now().Unix()+duration)
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}
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// ExpireAt expires the data at when.
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func (db *DB) ExpireAt(key []byte, when int64) (int64, error) {
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if when <= time.Now().Unix() {
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return 0, errExpireValue
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}
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return db.setExpireAt(key, when)
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}
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// TTL returns the TTL of the data.
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func (db *DB) TTL(key []byte) (int64, error) {
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if err := checkKeySize(key); err != nil {
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return -1, err
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}
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return db.ttl(KVType, key)
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}
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// Persist removes the TTL of the data.
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func (db *DB) Persist(key []byte) (int64, error) {
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if err := checkKeySize(key); err != nil {
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return 0, err
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}
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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n, err := db.rmExpire(t, KVType, key)
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if err != nil {
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return 0, err
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}
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err = t.Commit()
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return n, err
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}
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// SetRange sets the data with new value from offset.
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func (db *DB) SetRange(key []byte, offset int, value []byte) (int64, error) {
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if len(value) == 0 {
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return 0, nil
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}
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if err := checkKeySize(key); err != nil {
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return 0, err
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} else if len(value)+offset > MaxValueSize {
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return 0, errValueSize
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}
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key = db.encodeKVKey(key)
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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oldValue, err := db.bucket.Get(key)
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if err != nil {
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return 0, err
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}
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extra := offset + len(value) - len(oldValue)
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if extra > 0 {
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oldValue = append(oldValue, make([]byte, extra)...)
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}
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copy(oldValue[offset:], value)
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t.Put(key, oldValue)
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if err := t.Commit(); err != nil {
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return 0, err
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}
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return int64(len(oldValue)), nil
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}
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func getRange(start int, end int, valLen int) (int, int) {
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if start < 0 {
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start = valLen + start
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}
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if end < 0 {
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end = valLen + end
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}
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if start < 0 {
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start = 0
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}
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if end < 0 {
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end = 0
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}
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if end >= valLen {
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end = valLen - 1
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}
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return start, end
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}
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// GetRange gets the range of the data.
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func (db *DB) GetRange(key []byte, start int, end int) ([]byte, error) {
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if err := checkKeySize(key); err != nil {
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return nil, err
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}
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key = db.encodeKVKey(key)
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value, err := db.bucket.Get(key)
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if err != nil {
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return nil, err
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}
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valLen := len(value)
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start, end = getRange(start, end, valLen)
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if start > end {
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return nil, nil
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}
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return value[start : end+1], nil
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}
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// StrLen returns the length of the data.
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func (db *DB) StrLen(key []byte) (int64, error) {
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s, err := db.GetSlice(key)
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if err != nil {
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return 0, err
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}
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n := s.Size()
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s.Free()
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return int64(n), nil
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}
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// Append appends the value to the data.
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func (db *DB) Append(key []byte, value []byte) (int64, error) {
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if len(value) == 0 {
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return 0, nil
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}
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if err := checkKeySize(key); err != nil {
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return 0, err
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}
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key = db.encodeKVKey(key)
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t := db.kvBatch
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t.Lock()
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defer t.Unlock()
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oldValue, err := db.bucket.Get(key)
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if err != nil {
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return 0, err
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}
|
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|
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if len(oldValue)+len(value) > MaxValueSize {
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return 0, errValueSize
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}
|
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|
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oldValue = append(oldValue, value...)
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t.Put(key, oldValue)
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|
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if err := t.Commit(); err != nil {
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return 0, nil
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}
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return int64(len(oldValue)), nil
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}
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|
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// BitOP does the bit operations in data.
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func (db *DB) BitOP(op string, destKey []byte, srcKeys ...[]byte) (int64, error) {
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if err := checkKeySize(destKey); err != nil {
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return 0, err
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}
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|
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op = strings.ToLower(op)
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if len(srcKeys) == 0 {
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return 0, nil
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} else if op == BitNot && len(srcKeys) > 1 {
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return 0, fmt.Errorf("BITOP NOT has only one srckey")
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} else if len(srcKeys) < 2 {
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return 0, nil
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}
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|
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key := db.encodeKVKey(srcKeys[0])
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|
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value, err := db.bucket.Get(key)
|
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if err != nil {
|
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return 0, err
|
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}
|
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|
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if op == BitNot {
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for i := 0; i < len(value); i++ {
|
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value[i] = ^value[i]
|
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}
|
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} else {
|
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for j := 1; j < len(srcKeys); j++ {
|
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if err := checkKeySize(srcKeys[j]); err != nil {
|
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return 0, err
|
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}
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|
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key = db.encodeKVKey(srcKeys[j])
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ovalue, err := db.bucket.Get(key)
|
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if err != nil {
|
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return 0, err
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}
|
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|
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if len(value) < len(ovalue) {
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value, ovalue = ovalue, value
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}
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|
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for i := 0; i < len(ovalue); i++ {
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switch op {
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case BitAND:
|
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value[i] &= ovalue[i]
|
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case BitOR:
|
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value[i] |= ovalue[i]
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case BitXOR:
|
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value[i] ^= ovalue[i]
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default:
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return 0, fmt.Errorf("invalid op type: %s", op)
|
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}
|
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}
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|
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for i := len(ovalue); i < len(value); i++ {
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switch op {
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case BitAND:
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value[i] &= 0
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case BitOR:
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value[i] |= 0
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case BitXOR:
|
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value[i] ^= 0
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}
|
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}
|
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}
|
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}
|
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|
|
key = db.encodeKVKey(destKey)
|
|
|
|
t := db.kvBatch
|
|
|
|
t.Lock()
|
|
defer t.Unlock()
|
|
|
|
t.Put(key, value)
|
|
|
|
if err := t.Commit(); err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
return int64(len(value)), nil
|
|
}
|
|
|
|
var bitsInByte = [256]int32{0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3,
|
|
4, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 1, 2, 2, 3, 2, 3,
|
|
3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4,
|
|
5, 5, 6, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4,
|
|
3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4,
|
|
5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 1, 2,
|
|
2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3,
|
|
4, 4, 5, 4, 5, 5, 6, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
|
|
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 2, 3, 3, 4, 3, 4, 4,
|
|
5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6,
|
|
6, 7, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 4, 5, 5, 6, 5,
|
|
6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8}
|
|
|
|
func numberBitCount(i uint32) uint32 {
|
|
i = i - ((i >> 1) & 0x55555555)
|
|
i = (i & 0x33333333) + ((i >> 2) & 0x33333333)
|
|
return (((i + (i >> 4)) & 0x0F0F0F0F) * 0x01010101) >> 24
|
|
}
|
|
|
|
// BitCount returns the bit count of data.
|
|
func (db *DB) BitCount(key []byte, start int, end int) (int64, error) {
|
|
if err := checkKeySize(key); err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
key = db.encodeKVKey(key)
|
|
value, err := db.bucket.Get(key)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
start, end = getRange(start, end, len(value))
|
|
value = value[start : end+1]
|
|
|
|
var n int64
|
|
|
|
pos := 0
|
|
for ; pos+4 <= len(value); pos = pos + 4 {
|
|
n += int64(numberBitCount(binary.BigEndian.Uint32(value[pos : pos+4])))
|
|
}
|
|
|
|
for ; pos < len(value); pos++ {
|
|
n += int64(bitsInByte[value[pos]])
|
|
}
|
|
|
|
return n, nil
|
|
}
|
|
|
|
// BitPos returns the pos of the data.
|
|
func (db *DB) BitPos(key []byte, on int, start int, end int) (int64, error) {
|
|
if err := checkKeySize(key); err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
if (on & ^1) != 0 {
|
|
return 0, fmt.Errorf("bit must be 0 or 1, not %d", on)
|
|
}
|
|
|
|
var skipValue uint8
|
|
if on == 0 {
|
|
skipValue = 0xFF
|
|
}
|
|
|
|
key = db.encodeKVKey(key)
|
|
value, err := db.bucket.Get(key)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
start, end = getRange(start, end, len(value))
|
|
value = value[start : end+1]
|
|
|
|
for i, v := range value {
|
|
if uint8(v) != skipValue {
|
|
for j := 0; j < 8; j++ {
|
|
isNull := uint8(v)&(1<<uint8(7-j)) == 0
|
|
|
|
if (on == 1 && !isNull) || (on == 0 && isNull) {
|
|
return int64((start+i)*8 + j), nil
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return -1, nil
|
|
}
|
|
|
|
// SetBit sets the bit to the data.
|
|
func (db *DB) SetBit(key []byte, offset int, on int) (int64, error) {
|
|
if err := checkKeySize(key); err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
if (on & ^1) != 0 {
|
|
return 0, fmt.Errorf("bit must be 0 or 1, not %d", on)
|
|
}
|
|
|
|
t := db.kvBatch
|
|
|
|
t.Lock()
|
|
defer t.Unlock()
|
|
|
|
key = db.encodeKVKey(key)
|
|
value, err := db.bucket.Get(key)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
byteOffset := int(uint32(offset) >> 3)
|
|
extra := byteOffset + 1 - len(value)
|
|
if extra > 0 {
|
|
value = append(value, make([]byte, extra)...)
|
|
}
|
|
|
|
byteVal := value[byteOffset]
|
|
bit := 7 - uint8(uint32(offset)&0x7)
|
|
bitVal := byteVal & (1 << bit)
|
|
|
|
byteVal &= ^(1 << bit)
|
|
byteVal |= (uint8(on&0x1) << bit)
|
|
|
|
value[byteOffset] = byteVal
|
|
|
|
t.Put(key, value)
|
|
if err := t.Commit(); err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
if bitVal > 0 {
|
|
return 1, nil
|
|
}
|
|
|
|
return 0, nil
|
|
}
|
|
|
|
// GetBit gets the bit of data at offset.
|
|
func (db *DB) GetBit(key []byte, offset int) (int64, error) {
|
|
if err := checkKeySize(key); err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
key = db.encodeKVKey(key)
|
|
|
|
value, err := db.bucket.Get(key)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
byteOffset := uint32(offset) >> 3
|
|
bit := 7 - uint8(uint32(offset)&0x7)
|
|
|
|
if byteOffset >= uint32(len(value)) {
|
|
return 0, nil
|
|
}
|
|
|
|
bitVal := value[byteOffset] & (1 << bit)
|
|
if bitVal > 0 {
|
|
return 1, nil
|
|
}
|
|
|
|
return 0, nil
|
|
}
|