githaven-fork/vendor/github.com/lunny/nodb/t_bit.go
2019-02-05 11:52:51 -05:00

923 lines
18 KiB
Go
Vendored

package nodb
import (
"encoding/binary"
"errors"
"sort"
"time"
"github.com/lunny/nodb/store"
)
const (
OPand uint8 = iota + 1
OPor
OPxor
OPnot
)
type BitPair struct {
Pos int32
Val uint8
}
type segBitInfo struct {
Seq uint32
Off uint32
Val uint8
}
type segBitInfoArray []segBitInfo
const (
// byte
segByteWidth uint32 = 9
segByteSize uint32 = 1 << segByteWidth
// bit
segBitWidth uint32 = segByteWidth + 3
segBitSize uint32 = segByteSize << 3
maxByteSize uint32 = 8 << 20
maxSegCount uint32 = maxByteSize / segByteSize
minSeq uint32 = 0
maxSeq uint32 = uint32((maxByteSize << 3) - 1)
)
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}
var fillBits = [...]uint8{1, 3, 7, 15, 31, 63, 127, 255}
var emptySegment []byte = make([]byte, segByteSize, segByteSize)
var fillSegment []byte = func() []byte {
data := make([]byte, segByteSize, segByteSize)
for i := uint32(0); i < segByteSize; i++ {
data[i] = 0xff
}
return data
}()
var errBinKey = errors.New("invalid bin key")
var errOffset = errors.New("invalid offset")
var errDuplicatePos = errors.New("duplicate bit pos")
func getBit(sz []byte, offset uint32) uint8 {
index := offset >> 3
if index >= uint32(len(sz)) {
return 0 // error("overflow")
}
offset -= index << 3
return sz[index] >> offset & 1
}
func setBit(sz []byte, offset uint32, val uint8) bool {
if val != 1 && val != 0 {
return false // error("invalid val")
}
index := offset >> 3
if index >= uint32(len(sz)) {
return false // error("overflow")
}
offset -= index << 3
if sz[index]>>offset&1 != val {
sz[index] ^= (1 << offset)
}
return true
}
func (datas segBitInfoArray) Len() int {
return len(datas)
}
func (datas segBitInfoArray) Less(i, j int) bool {
res := (datas)[i].Seq < (datas)[j].Seq
if !res && (datas)[i].Seq == (datas)[j].Seq {
res = (datas)[i].Off < (datas)[j].Off
}
return res
}
func (datas segBitInfoArray) Swap(i, j int) {
datas[i], datas[j] = datas[j], datas[i]
}
func (db *DB) bEncodeMetaKey(key []byte) []byte {
mk := make([]byte, len(key)+2)
mk[0] = db.index
mk[1] = BitMetaType
copy(mk[2:], key)
return mk
}
func (db *DB) bDecodeMetaKey(bkey []byte) ([]byte, error) {
if len(bkey) < 2 || bkey[0] != db.index || bkey[1] != BitMetaType {
return nil, errBinKey
}
return bkey[2:], nil
}
func (db *DB) bEncodeBinKey(key []byte, seq uint32) []byte {
bk := make([]byte, len(key)+8)
pos := 0
bk[pos] = db.index
pos++
bk[pos] = BitType
pos++
binary.BigEndian.PutUint16(bk[pos:], uint16(len(key)))
pos += 2
copy(bk[pos:], key)
pos += len(key)
binary.BigEndian.PutUint32(bk[pos:], seq)
return bk
}
func (db *DB) bDecodeBinKey(bkey []byte) (key []byte, seq uint32, err error) {
if len(bkey) < 8 || bkey[0] != db.index {
err = errBinKey
return
}
keyLen := binary.BigEndian.Uint16(bkey[2:4])
if int(keyLen+8) != len(bkey) {
err = errBinKey
return
}
key = bkey[4 : 4+keyLen]
seq = uint32(binary.BigEndian.Uint32(bkey[4+keyLen:]))
return
}
func (db *DB) bCapByteSize(seq uint32, off uint32) uint32 {
var offByteSize uint32 = (off >> 3) + 1
if offByteSize > segByteSize {
offByteSize = segByteSize
}
return seq<<segByteWidth + offByteSize
}
func (db *DB) bParseOffset(key []byte, offset int32) (seq uint32, off uint32, err error) {
if offset < 0 {
if tailSeq, tailOff, e := db.bGetMeta(key); e != nil {
err = e
return
} else if tailSeq >= 0 {
offset += int32((uint32(tailSeq)<<segBitWidth | uint32(tailOff)) + 1)
if offset < 0 {
err = errOffset
return
}
}
}
off = uint32(offset)
seq = off >> segBitWidth
off &= (segBitSize - 1)
return
}
func (db *DB) bGetMeta(key []byte) (tailSeq int32, tailOff int32, err error) {
var v []byte
mk := db.bEncodeMetaKey(key)
v, err = db.bucket.Get(mk)
if err != nil {
return
}
if v != nil {
tailSeq = int32(binary.LittleEndian.Uint32(v[0:4]))
tailOff = int32(binary.LittleEndian.Uint32(v[4:8]))
} else {
tailSeq = -1
tailOff = -1
}
return
}
func (db *DB) bSetMeta(t *batch, key []byte, tailSeq uint32, tailOff uint32) {
ek := db.bEncodeMetaKey(key)
buf := make([]byte, 8)
binary.LittleEndian.PutUint32(buf[0:4], tailSeq)
binary.LittleEndian.PutUint32(buf[4:8], tailOff)
t.Put(ek, buf)
return
}
func (db *DB) bUpdateMeta(t *batch, key []byte, seq uint32, off uint32) (tailSeq uint32, tailOff uint32, err error) {
var tseq, toff int32
var update bool = false
if tseq, toff, err = db.bGetMeta(key); err != nil {
return
} else if tseq < 0 {
update = true
} else {
tailSeq = uint32(MaxInt32(tseq, 0))
tailOff = uint32(MaxInt32(toff, 0))
update = (seq > tailSeq || (seq == tailSeq && off > tailOff))
}
if update {
db.bSetMeta(t, key, seq, off)
tailSeq = seq
tailOff = off
}
return
}
func (db *DB) bDelete(t *batch, key []byte) (drop int64) {
mk := db.bEncodeMetaKey(key)
t.Delete(mk)
minKey := db.bEncodeBinKey(key, minSeq)
maxKey := db.bEncodeBinKey(key, maxSeq)
it := db.bucket.RangeIterator(minKey, maxKey, store.RangeClose)
for ; it.Valid(); it.Next() {
t.Delete(it.RawKey())
drop++
}
it.Close()
return drop
}
func (db *DB) bGetSegment(key []byte, seq uint32) ([]byte, []byte, error) {
bk := db.bEncodeBinKey(key, seq)
segment, err := db.bucket.Get(bk)
if err != nil {
return bk, nil, err
}
return bk, segment, nil
}
func (db *DB) bAllocateSegment(key []byte, seq uint32) ([]byte, []byte, error) {
bk, segment, err := db.bGetSegment(key, seq)
if err == nil && segment == nil {
segment = make([]byte, segByteSize, segByteSize)
}
return bk, segment, err
}
func (db *DB) bIterator(key []byte) *store.RangeLimitIterator {
sk := db.bEncodeBinKey(key, minSeq)
ek := db.bEncodeBinKey(key, maxSeq)
return db.bucket.RangeIterator(sk, ek, store.RangeClose)
}
func (db *DB) bSegAnd(a []byte, b []byte, res *[]byte) {
if a == nil || b == nil {
*res = nil
return
}
data := *res
if data == nil {
data = make([]byte, segByteSize, segByteSize)
*res = data
}
for i := uint32(0); i < segByteSize; i++ {
data[i] = a[i] & b[i]
}
return
}
func (db *DB) bSegOr(a []byte, b []byte, res *[]byte) {
if a == nil || b == nil {
if a == nil && b == nil {
*res = nil
} else if a == nil {
*res = b
} else {
*res = a
}
return
}
data := *res
if data == nil {
data = make([]byte, segByteSize, segByteSize)
*res = data
}
for i := uint32(0); i < segByteSize; i++ {
data[i] = a[i] | b[i]
}
return
}
func (db *DB) bSegXor(a []byte, b []byte, res *[]byte) {
if a == nil && b == nil {
*res = fillSegment
return
}
if a == nil {
a = emptySegment
}
if b == nil {
b = emptySegment
}
data := *res
if data == nil {
data = make([]byte, segByteSize, segByteSize)
*res = data
}
for i := uint32(0); i < segByteSize; i++ {
data[i] = a[i] ^ b[i]
}
return
}
func (db *DB) bExpireAt(key []byte, when int64) (int64, error) {
t := db.binBatch
t.Lock()
defer t.Unlock()
if seq, _, err := db.bGetMeta(key); err != nil || seq < 0 {
return 0, err
} else {
db.expireAt(t, BitType, key, when)
if err := t.Commit(); err != nil {
return 0, err
}
}
return 1, nil
}
func (db *DB) bCountByte(val byte, soff uint32, eoff uint32) int32 {
if soff > eoff {
soff, eoff = eoff, soff
}
mask := uint8(0)
if soff > 0 {
mask |= fillBits[soff-1]
}
if eoff < 7 {
mask |= (fillBits[7] ^ fillBits[eoff])
}
mask = fillBits[7] ^ mask
return bitsInByte[val&mask]
}
func (db *DB) bCountSeg(key []byte, seq uint32, soff uint32, eoff uint32) (cnt int32, err error) {
if soff >= segBitSize || soff < 0 ||
eoff >= segBitSize || eoff < 0 {
return
}
var segment []byte
if _, segment, err = db.bGetSegment(key, seq); err != nil {
return
}
if segment == nil {
return
}
if soff > eoff {
soff, eoff = eoff, soff
}
headIdx := int(soff >> 3)
endIdx := int(eoff >> 3)
sByteOff := soff - ((soff >> 3) << 3)
eByteOff := eoff - ((eoff >> 3) << 3)
if headIdx == endIdx {
cnt = db.bCountByte(segment[headIdx], sByteOff, eByteOff)
} else {
cnt = db.bCountByte(segment[headIdx], sByteOff, 7) +
db.bCountByte(segment[endIdx], 0, eByteOff)
}
// sum up following bytes
for idx, end := headIdx+1, endIdx-1; idx <= end; idx += 1 {
cnt += bitsInByte[segment[idx]]
if idx == end {
break
}
}
return
}
func (db *DB) BGet(key []byte) (data []byte, err error) {
if err = checkKeySize(key); err != nil {
return
}
var ts, to int32
if ts, to, err = db.bGetMeta(key); err != nil || ts < 0 {
return
}
var tailSeq, tailOff = uint32(ts), uint32(to)
var capByteSize uint32 = db.bCapByteSize(tailSeq, tailOff)
data = make([]byte, capByteSize, capByteSize)
minKey := db.bEncodeBinKey(key, minSeq)
maxKey := db.bEncodeBinKey(key, tailSeq)
it := db.bucket.RangeIterator(minKey, maxKey, store.RangeClose)
var seq, s, e uint32
for ; it.Valid(); it.Next() {
if _, seq, err = db.bDecodeBinKey(it.RawKey()); err != nil {
data = nil
break
}
s = seq << segByteWidth
e = MinUInt32(s+segByteSize, capByteSize)
copy(data[s:e], it.RawValue())
}
it.Close()
return
}
func (db *DB) BDelete(key []byte) (drop int64, err error) {
if err = checkKeySize(key); err != nil {
return
}
t := db.binBatch
t.Lock()
defer t.Unlock()
drop = db.bDelete(t, key)
db.rmExpire(t, BitType, key)
err = t.Commit()
return
}
func (db *DB) BSetBit(key []byte, offset int32, val uint8) (ori uint8, err error) {
if err = checkKeySize(key); err != nil {
return
}
// todo : check offset
var seq, off uint32
if seq, off, err = db.bParseOffset(key, offset); err != nil {
return 0, err
}
var bk, segment []byte
if bk, segment, err = db.bAllocateSegment(key, seq); err != nil {
return 0, err
}
if segment != nil {
ori = getBit(segment, off)
if setBit(segment, off, val) {
t := db.binBatch
t.Lock()
defer t.Unlock()
t.Put(bk, segment)
if _, _, e := db.bUpdateMeta(t, key, seq, off); e != nil {
err = e
return
}
err = t.Commit()
}
}
return
}
func (db *DB) BMSetBit(key []byte, args ...BitPair) (place int64, err error) {
if err = checkKeySize(key); err != nil {
return
}
// (ps : so as to aviod wasting memory copy while calling db.Get() and batch.Put(),
// here we sequence the params by pos, so that we can merge the execution of
// diff pos setting which targets on the same segment respectively. )
// #1 : sequence request data
var argCnt = len(args)
var bitInfos segBitInfoArray = make(segBitInfoArray, argCnt)
var seq, off uint32
for i, info := range args {
if seq, off, err = db.bParseOffset(key, info.Pos); err != nil {
return
}
bitInfos[i].Seq = seq
bitInfos[i].Off = off
bitInfos[i].Val = info.Val
}
sort.Sort(bitInfos)
for i := 1; i < argCnt; i++ {
if bitInfos[i].Seq == bitInfos[i-1].Seq && bitInfos[i].Off == bitInfos[i-1].Off {
return 0, errDuplicatePos
}
}
// #2 : execute bit set in order
t := db.binBatch
t.Lock()
defer t.Unlock()
var curBinKey, curSeg []byte
var curSeq, maxSeq, maxOff uint32
for _, info := range bitInfos {
if curSeg != nil && info.Seq != curSeq {
t.Put(curBinKey, curSeg)
curSeg = nil
}
if curSeg == nil {
curSeq = info.Seq
if curBinKey, curSeg, err = db.bAllocateSegment(key, info.Seq); err != nil {
return
}
if curSeg == nil {
continue
}
}
if setBit(curSeg, info.Off, info.Val) {
maxSeq = info.Seq
maxOff = info.Off
place++
}
}
if curSeg != nil {
t.Put(curBinKey, curSeg)
}
// finally, update meta
if place > 0 {
if _, _, err = db.bUpdateMeta(t, key, maxSeq, maxOff); err != nil {
return
}
err = t.Commit()
}
return
}
func (db *DB) BGetBit(key []byte, offset int32) (uint8, error) {
if seq, off, err := db.bParseOffset(key, offset); err != nil {
return 0, err
} else {
_, segment, err := db.bGetSegment(key, seq)
if err != nil {
return 0, err
}
if segment == nil {
return 0, nil
} else {
return getBit(segment, off), nil
}
}
}
// func (db *DB) BGetRange(key []byte, start int32, end int32) ([]byte, error) {
// section := make([]byte)
// return
// }
func (db *DB) BCount(key []byte, start int32, end int32) (cnt int32, err error) {
var sseq, soff uint32
if sseq, soff, err = db.bParseOffset(key, start); err != nil {
return
}
var eseq, eoff uint32
if eseq, eoff, err = db.bParseOffset(key, end); err != nil {
return
}
if sseq > eseq || (sseq == eseq && soff > eoff) {
sseq, eseq = eseq, sseq
soff, eoff = eoff, soff
}
var segCnt int32
if eseq == sseq {
if segCnt, err = db.bCountSeg(key, sseq, soff, eoff); err != nil {
return 0, err
}
cnt = segCnt
} else {
if segCnt, err = db.bCountSeg(key, sseq, soff, segBitSize-1); err != nil {
return 0, err
} else {
cnt += segCnt
}
if segCnt, err = db.bCountSeg(key, eseq, 0, eoff); err != nil {
return 0, err
} else {
cnt += segCnt
}
}
// middle segs
var segment []byte
skey := db.bEncodeBinKey(key, sseq)
ekey := db.bEncodeBinKey(key, eseq)
it := db.bucket.RangeIterator(skey, ekey, store.RangeOpen)
for ; it.Valid(); it.Next() {
segment = it.RawValue()
for _, bt := range segment {
cnt += bitsInByte[bt]
}
}
it.Close()
return
}
func (db *DB) BTail(key []byte) (int32, error) {
// effective length of data, the highest bit-pos set in history
tailSeq, tailOff, err := db.bGetMeta(key)
if err != nil {
return 0, err
}
tail := int32(-1)
if tailSeq >= 0 {
tail = int32(uint32(tailSeq)<<segBitWidth | uint32(tailOff))
}
return tail, nil
}
func (db *DB) BOperation(op uint8, dstkey []byte, srckeys ...[]byte) (blen int32, err error) {
// blen -
// the total bit size of data stored in destination key,
// that is equal to the size of the longest input string.
var exeOp func([]byte, []byte, *[]byte)
switch op {
case OPand:
exeOp = db.bSegAnd
case OPor:
exeOp = db.bSegOr
case OPxor, OPnot:
exeOp = db.bSegXor
default:
return
}
if dstkey == nil || srckeys == nil {
return
}
t := db.binBatch
t.Lock()
defer t.Unlock()
var srcKseq, srcKoff int32
var seq, off, maxDstSeq, maxDstOff uint32
var keyNum int = len(srckeys)
var validKeyNum int
for i := 0; i < keyNum; i++ {
if srcKseq, srcKoff, err = db.bGetMeta(srckeys[i]); err != nil {
return
} else if srcKseq < 0 {
srckeys[i] = nil
continue
}
validKeyNum++
seq = uint32(srcKseq)
off = uint32(srcKoff)
if seq > maxDstSeq || (seq == maxDstSeq && off > maxDstOff) {
maxDstSeq = seq
maxDstOff = off
}
}
if (op == OPnot && validKeyNum != 1) ||
(op != OPnot && validKeyNum < 2) {
return // with not enough existing source key
}
var srcIdx int
for srcIdx = 0; srcIdx < keyNum; srcIdx++ {
if srckeys[srcIdx] != nil {
break
}
}
// init - data
var segments = make([][]byte, maxDstSeq+1)
if op == OPnot {
// ps :
// ( ~num == num ^ 0x11111111 )
// we init the result segments with all bit set,
// then we can calculate through the way of 'xor'.
// ahead segments bin format : 1111 ... 1111
for i := uint32(0); i < maxDstSeq; i++ {
segments[i] = fillSegment
}
// last segment bin format : 1111..1100..0000
var tailSeg = make([]byte, segByteSize, segByteSize)
var fillByte = fillBits[7]
var tailSegLen = db.bCapByteSize(uint32(0), maxDstOff)
for i := uint32(0); i < tailSegLen-1; i++ {
tailSeg[i] = fillByte
}
tailSeg[tailSegLen-1] = fillBits[maxDstOff-(tailSegLen-1)<<3]
segments[maxDstSeq] = tailSeg
} else {
// ps : init segments by data corresponding to the 1st valid source key
it := db.bIterator(srckeys[srcIdx])
for ; it.Valid(); it.Next() {
if _, seq, err = db.bDecodeBinKey(it.RawKey()); err != nil {
// to do ...
it.Close()
return
}
segments[seq] = it.Value()
}
it.Close()
srcIdx++
}
// operation with following keys
var res []byte
for i := srcIdx; i < keyNum; i++ {
if srckeys[i] == nil {
continue
}
it := db.bIterator(srckeys[i])
for idx, end := uint32(0), false; !end; it.Next() {
end = !it.Valid()
if !end {
if _, seq, err = db.bDecodeBinKey(it.RawKey()); err != nil {
// to do ...
it.Close()
return
}
} else {
seq = maxDstSeq + 1
}
// todo :
// operation 'and' can be optimize here :
// if seq > max_segments_idx, this loop can be break,
// which can avoid cost from Key() and bDecodeBinKey()
for ; idx < seq; idx++ {
res = nil
exeOp(segments[idx], nil, &res)
segments[idx] = res
}
if !end {
res = it.Value()
exeOp(segments[seq], res, &res)
segments[seq] = res
idx++
}
}
it.Close()
}
// clear the old data in case
db.bDelete(t, dstkey)
db.rmExpire(t, BitType, dstkey)
// set data
db.bSetMeta(t, dstkey, maxDstSeq, maxDstOff)
var bk []byte
for seq, segt := range segments {
if segt != nil {
bk = db.bEncodeBinKey(dstkey, uint32(seq))
t.Put(bk, segt)
}
}
err = t.Commit()
if err == nil {
// blen = int32(db.bCapByteSize(maxDstOff, maxDstOff))
blen = int32(maxDstSeq<<segBitWidth | maxDstOff + 1)
}
return
}
func (db *DB) BExpire(key []byte, duration int64) (int64, error) {
if duration <= 0 {
return 0, errExpireValue
}
if err := checkKeySize(key); err != nil {
return -1, err
}
return db.bExpireAt(key, time.Now().Unix()+duration)
}
func (db *DB) BExpireAt(key []byte, when int64) (int64, error) {
if when <= time.Now().Unix() {
return 0, errExpireValue
}
if err := checkKeySize(key); err != nil {
return -1, err
}
return db.bExpireAt(key, when)
}
func (db *DB) BTTL(key []byte) (int64, error) {
if err := checkKeySize(key); err != nil {
return -1, err
}
return db.ttl(BitType, key)
}
func (db *DB) BPersist(key []byte) (int64, error) {
if err := checkKeySize(key); err != nil {
return 0, err
}
t := db.binBatch
t.Lock()
defer t.Unlock()
n, err := db.rmExpire(t, BitType, key)
if err != nil {
return 0, err
}
err = t.Commit()
return n, err
}
func (db *DB) BScan(key []byte, count int, inclusive bool, match string) ([][]byte, error) {
return db.scan(BitMetaType, key, count, inclusive, match)
}
func (db *DB) bFlush() (drop int64, err error) {
t := db.binBatch
t.Lock()
defer t.Unlock()
return db.flushType(t, BitType)
}