seaweedfs/weed/storage/needle/needle_read_write.go
2021-02-20 12:39:25 -08:00

411 lines
12 KiB
Go

package needle
import (
"errors"
"fmt"
"io"
"math"
"github.com/chrislusf/seaweedfs/weed/glog"
"github.com/chrislusf/seaweedfs/weed/storage/backend"
. "github.com/chrislusf/seaweedfs/weed/storage/types"
"github.com/chrislusf/seaweedfs/weed/util"
)
const (
FlagIsCompressed = 0x01
FlagHasName = 0x02
FlagHasMime = 0x04
FlagHasLastModifiedDate = 0x08
FlagHasTtl = 0x10
FlagHasPairs = 0x20
FlagIsChunkManifest = 0x80
LastModifiedBytesLength = 5
TtlBytesLength = 2
)
var ErrorSizeMismatch = errors.New("size mismatch")
func (n *Needle) DiskSize(version Version) int64 {
return GetActualSize(n.Size, version)
}
func (n *Needle) prepareWriteBuffer(version Version) ([]byte, Size, int64, error) {
writeBytes := make([]byte, 0)
switch version {
case Version1:
header := make([]byte, NeedleHeaderSize)
CookieToBytes(header[0:CookieSize], n.Cookie)
NeedleIdToBytes(header[CookieSize:CookieSize+NeedleIdSize], n.Id)
n.Size = Size(len(n.Data))
SizeToBytes(header[CookieSize+NeedleIdSize:CookieSize+NeedleIdSize+SizeSize], n.Size)
size := n.Size
actualSize := NeedleHeaderSize + int64(n.Size)
writeBytes = append(writeBytes, header...)
writeBytes = append(writeBytes, n.Data...)
padding := PaddingLength(n.Size, version)
util.Uint32toBytes(header[0:NeedleChecksumSize], n.Checksum.Value())
writeBytes = append(writeBytes, header[0:NeedleChecksumSize+padding]...)
return writeBytes, size, actualSize, nil
case Version2, Version3:
header := make([]byte, NeedleHeaderSize+TimestampSize) // adding timestamp to reuse it and avoid extra allocation
CookieToBytes(header[0:CookieSize], n.Cookie)
NeedleIdToBytes(header[CookieSize:CookieSize+NeedleIdSize], n.Id)
if len(n.Name) >= math.MaxUint8 {
n.NameSize = math.MaxUint8
} else {
n.NameSize = uint8(len(n.Name))
}
n.DataSize, n.MimeSize = uint32(len(n.Data)), uint8(len(n.Mime))
if n.DataSize > 0 {
n.Size = 4 + Size(n.DataSize) + 1
if n.HasName() {
n.Size = n.Size + 1 + Size(n.NameSize)
}
if n.HasMime() {
n.Size = n.Size + 1 + Size(n.MimeSize)
}
if n.HasLastModifiedDate() {
n.Size = n.Size + LastModifiedBytesLength
}
if n.HasTtl() {
n.Size = n.Size + TtlBytesLength
}
if n.HasPairs() {
n.Size += 2 + Size(n.PairsSize)
}
} else {
n.Size = 0
}
SizeToBytes(header[CookieSize+NeedleIdSize:CookieSize+NeedleIdSize+SizeSize], n.Size)
writeBytes = append(writeBytes, header[0:NeedleHeaderSize]...)
if n.DataSize > 0 {
util.Uint32toBytes(header[0:4], n.DataSize)
writeBytes = append(writeBytes, header[0:4]...)
writeBytes = append(writeBytes, n.Data...)
util.Uint8toBytes(header[0:1], n.Flags)
writeBytes = append(writeBytes, header[0:1]...)
if n.HasName() {
util.Uint8toBytes(header[0:1], n.NameSize)
writeBytes = append(writeBytes, header[0:1]...)
writeBytes = append(writeBytes, n.Name[:n.NameSize]...)
}
if n.HasMime() {
util.Uint8toBytes(header[0:1], n.MimeSize)
writeBytes = append(writeBytes, header[0:1]...)
writeBytes = append(writeBytes, n.Mime...)
}
if n.HasLastModifiedDate() {
util.Uint64toBytes(header[0:8], n.LastModified)
writeBytes = append(writeBytes, header[8-LastModifiedBytesLength:8]...)
}
if n.HasTtl() && n.Ttl != nil {
n.Ttl.ToBytes(header[0:TtlBytesLength])
writeBytes = append(writeBytes, header[0:TtlBytesLength]...)
}
if n.HasPairs() {
util.Uint16toBytes(header[0:2], n.PairsSize)
writeBytes = append(writeBytes, header[0:2]...)
writeBytes = append(writeBytes, n.Pairs...)
}
}
padding := PaddingLength(n.Size, version)
util.Uint32toBytes(header[0:NeedleChecksumSize], n.Checksum.Value())
if version == Version2 {
writeBytes = append(writeBytes, header[0:NeedleChecksumSize+padding]...)
} else {
// version3
util.Uint64toBytes(header[NeedleChecksumSize:NeedleChecksumSize+TimestampSize], n.AppendAtNs)
writeBytes = append(writeBytes, header[0:NeedleChecksumSize+TimestampSize+padding]...)
}
return writeBytes, Size(n.DataSize), GetActualSize(n.Size, version), nil
}
return writeBytes, 0, 0, fmt.Errorf("Unsupported Version! (%d)", version)
}
func (n *Needle) Append(w backend.BackendStorageFile, version Version) (offset uint64, size Size, actualSize int64, err error) {
if end, _, e := w.GetStat(); e == nil {
defer func(w backend.BackendStorageFile, off int64) {
if err != nil {
if te := w.Truncate(end); te != nil {
glog.V(0).Infof("Failed to truncate %s back to %d with error: %v", w.Name(), end, te)
}
}
}(w, end)
offset = uint64(end)
} else {
err = fmt.Errorf("Cannot Read Current Volume Position: %v", e)
return
}
if offset >= MaxPossibleVolumeSize {
err = fmt.Errorf("Volume Size %d Exeededs %d", offset, MaxPossibleVolumeSize)
return
}
bytesToWrite, size, actualSize, err := n.prepareWriteBuffer(version)
if err == nil {
_, err = w.WriteAt(bytesToWrite, int64(offset))
}
return offset, size, actualSize, err
}
func ReadNeedleBlob(r backend.BackendStorageFile, offset int64, size Size, version Version) (dataSlice []byte, err error) {
dataSize := GetActualSize(size, version)
dataSlice = make([]byte, int(dataSize))
var n int
n, err = r.ReadAt(dataSlice, offset)
if err != nil && int64(n) == dataSize {
err = nil
}
if err != nil {
fileSize, _, _ := r.GetStat()
println("n",n, "dataSize", dataSize, "offset", offset, "fileSize", fileSize)
}
return dataSlice, err
}
// ReadBytes hydrates the needle from the bytes buffer, with only n.Id is set.
func (n *Needle) ReadBytes(bytes []byte, offset int64, size Size, version Version) (err error) {
n.ParseNeedleHeader(bytes)
if n.Size != size {
// cookie is not always passed in for this API. Use size to do preliminary checking.
if OffsetSize == 4 && offset < int64(MaxPossibleVolumeSize) {
glog.Errorf("entry not found1: offset %d found id %x size %d, expected size %d", offset, n.Id, n.Size, size)
return ErrorSizeMismatch
}
return fmt.Errorf("entry not found: offset %d found id %x size %d, expected size %d", offset, n.Id, n.Size, size)
}
switch version {
case Version1:
n.Data = bytes[NeedleHeaderSize : NeedleHeaderSize+size]
case Version2, Version3:
err = n.readNeedleDataVersion2(bytes[NeedleHeaderSize : NeedleHeaderSize+int(n.Size)])
}
if err != nil && err != io.EOF {
return err
}
if size > 0 {
checksum := util.BytesToUint32(bytes[NeedleHeaderSize+size : NeedleHeaderSize+size+NeedleChecksumSize])
newChecksum := NewCRC(n.Data)
if checksum != newChecksum.Value() {
return errors.New("CRC error! Data On Disk Corrupted")
}
n.Checksum = newChecksum
}
if version == Version3 {
tsOffset := NeedleHeaderSize + size + NeedleChecksumSize
n.AppendAtNs = util.BytesToUint64(bytes[tsOffset : tsOffset+TimestampSize])
}
return nil
}
// ReadData hydrates the needle from the file, with only n.Id is set.
func (n *Needle) ReadData(r backend.BackendStorageFile, offset int64, size Size, version Version) (err error) {
bytes, err := ReadNeedleBlob(r, offset, size, version)
if err != nil {
return err
}
return n.ReadBytes(bytes, offset, size, version)
}
func (n *Needle) ParseNeedleHeader(bytes []byte) {
n.Cookie = BytesToCookie(bytes[0:CookieSize])
n.Id = BytesToNeedleId(bytes[CookieSize : CookieSize+NeedleIdSize])
n.Size = BytesToSize(bytes[CookieSize+NeedleIdSize : NeedleHeaderSize])
}
func (n *Needle) readNeedleDataVersion2(bytes []byte) (err error) {
index, lenBytes := 0, len(bytes)
if index < lenBytes {
n.DataSize = util.BytesToUint32(bytes[index : index+4])
index = index + 4
if int(n.DataSize)+index > lenBytes {
return fmt.Errorf("index out of range %d", 1)
}
n.Data = bytes[index : index+int(n.DataSize)]
index = index + int(n.DataSize)
n.Flags = bytes[index]
index = index + 1
}
if index < lenBytes && n.HasName() {
n.NameSize = uint8(bytes[index])
index = index + 1
if int(n.NameSize)+index > lenBytes {
return fmt.Errorf("index out of range %d", 2)
}
n.Name = bytes[index : index+int(n.NameSize)]
index = index + int(n.NameSize)
}
if index < lenBytes && n.HasMime() {
n.MimeSize = uint8(bytes[index])
index = index + 1
if int(n.MimeSize)+index > lenBytes {
return fmt.Errorf("index out of range %d", 3)
}
n.Mime = bytes[index : index+int(n.MimeSize)]
index = index + int(n.MimeSize)
}
if index < lenBytes && n.HasLastModifiedDate() {
if LastModifiedBytesLength+index > lenBytes {
return fmt.Errorf("index out of range %d", 4)
}
n.LastModified = util.BytesToUint64(bytes[index : index+LastModifiedBytesLength])
index = index + LastModifiedBytesLength
}
if index < lenBytes && n.HasTtl() {
if TtlBytesLength+index > lenBytes {
return fmt.Errorf("index out of range %d", 5)
}
n.Ttl = LoadTTLFromBytes(bytes[index : index+TtlBytesLength])
index = index + TtlBytesLength
}
if index < lenBytes && n.HasPairs() {
if 2+index > lenBytes {
return fmt.Errorf("index out of range %d", 6)
}
n.PairsSize = util.BytesToUint16(bytes[index : index+2])
index += 2
if int(n.PairsSize)+index > lenBytes {
return fmt.Errorf("index out of range %d", 7)
}
end := index + int(n.PairsSize)
n.Pairs = bytes[index:end]
index = end
}
return nil
}
func ReadNeedleHeader(r backend.BackendStorageFile, version Version, offset int64) (n *Needle, bytes []byte, bodyLength int64, err error) {
n = new(Needle)
if version == Version1 || version == Version2 || version == Version3 {
bytes = make([]byte, NeedleHeaderSize)
var count int
count, err = r.ReadAt(bytes, offset)
if count <= 0 || err != nil {
return nil, bytes, 0, err
}
n.ParseNeedleHeader(bytes)
bodyLength = NeedleBodyLength(n.Size, version)
}
return
}
func PaddingLength(needleSize Size, version Version) Size {
if version == Version3 {
// this is same value as version2, but just listed here for clarity
return NeedlePaddingSize - ((NeedleHeaderSize + needleSize + NeedleChecksumSize + TimestampSize) % NeedlePaddingSize)
}
return NeedlePaddingSize - ((NeedleHeaderSize + needleSize + NeedleChecksumSize) % NeedlePaddingSize)
}
func NeedleBodyLength(needleSize Size, version Version) int64 {
if version == Version3 {
return int64(needleSize) + NeedleChecksumSize + TimestampSize + int64(PaddingLength(needleSize, version))
}
return int64(needleSize) + NeedleChecksumSize + int64(PaddingLength(needleSize, version))
}
//n should be a needle already read the header
//the input stream will read until next file entry
func (n *Needle) ReadNeedleBody(r backend.BackendStorageFile, version Version, offset int64, bodyLength int64) (bytes []byte, err error) {
if bodyLength <= 0 {
return nil, nil
}
bytes = make([]byte, bodyLength)
if _, err = r.ReadAt(bytes, offset); err != nil {
return
}
err = n.ReadNeedleBodyBytes(bytes, version)
return
}
func (n *Needle) ReadNeedleBodyBytes(needleBody []byte, version Version) (err error) {
if len(needleBody) <= 0 {
return nil
}
switch version {
case Version1:
n.Data = needleBody[:n.Size]
n.Checksum = NewCRC(n.Data)
case Version2, Version3:
err = n.readNeedleDataVersion2(needleBody[0:n.Size])
n.Checksum = NewCRC(n.Data)
if version == Version3 {
tsOffset := n.Size + NeedleChecksumSize
n.AppendAtNs = util.BytesToUint64(needleBody[tsOffset : tsOffset+TimestampSize])
}
default:
err = fmt.Errorf("unsupported version %d!", version)
}
return
}
func (n *Needle) IsCompressed() bool {
return n.Flags&FlagIsCompressed > 0
}
func (n *Needle) SetIsCompressed() {
n.Flags = n.Flags | FlagIsCompressed
}
func (n *Needle) HasName() bool {
return n.Flags&FlagHasName > 0
}
func (n *Needle) SetHasName() {
n.Flags = n.Flags | FlagHasName
}
func (n *Needle) HasMime() bool {
return n.Flags&FlagHasMime > 0
}
func (n *Needle) SetHasMime() {
n.Flags = n.Flags | FlagHasMime
}
func (n *Needle) HasLastModifiedDate() bool {
return n.Flags&FlagHasLastModifiedDate > 0
}
func (n *Needle) SetHasLastModifiedDate() {
n.Flags = n.Flags | FlagHasLastModifiedDate
}
func (n *Needle) HasTtl() bool {
return n.Flags&FlagHasTtl > 0
}
func (n *Needle) SetHasTtl() {
n.Flags = n.Flags | FlagHasTtl
}
func (n *Needle) IsChunkedManifest() bool {
return n.Flags&FlagIsChunkManifest > 0
}
func (n *Needle) SetIsChunkManifest() {
n.Flags = n.Flags | FlagIsChunkManifest
}
func (n *Needle) HasPairs() bool {
return n.Flags&FlagHasPairs != 0
}
func (n *Needle) SetHasPairs() {
n.Flags = n.Flags | FlagHasPairs
}
func GetActualSize(size Size, version Version) int64 {
return NeedleHeaderSize + NeedleBodyLength(size, version)
}