minio/pkg/storage/donut/donut.go
2015-02-18 17:18:33 -08:00

91 lines
2.3 KiB
Go

/*
* Mini Object Storage, (C) 2015 Minio, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package donut
import (
"io"
)
/*
** DONUT v1 Spec **
BlockStart [4]byte // Magic="MINI"
VersionMajor uint16
VersionMinor uint16
VersionPatch uint16
VersionReserved uint16
Reserved uint64
GobHeaderLen uint32
GobHeader io.Reader // matches length
BlockData [4]byte // Magic="DATA"
Data io.Reader // matches length
BlockLen uint64 // length to block start
BlockEnd [4]byte // Magic="INIM"
*/
type DonutStructure struct {
BlockStart [4]byte // Magic="MINI"
VersionMajor uint16
VersionMinor uint16
VersionPatch uint16
VersionReserved uint16
Reserved uint64
GobHeaderLen uint32
GobHeader GobHeader
BlockData [4]byte
Data io.Reader
BlockLen uint64
BlockEnd [4]byte
}
type DonutFooter struct {
BlockLen uint64
BlockEnd uint32 // Magic="INIM"
}
type Donut struct {
file io.Writer
// mutex
}
type GobHeader struct{}
func (donut *Donut) Write(gobHeader GobHeader, object io.Reader) error {
// TODO mutex
// Create bytes buffer representing the new object
donutStructure := DonutStructure{
BlockStart: [4]byte{'M', 'I', 'N', 'I'},
VersionMajor: 1,
VersionMinor: 0,
VersionPatch: 0,
VersionReserved: 0,
Reserved: 0,
GobHeaderLen: 0,
GobHeader: gobHeader,
BlockData: [4]byte{'D', 'A', 'T', 'A'},
Data: object,
BlockLen: 0,
BlockEnd: [4]byte{'I', 'N', 'I', 'M'},
}
if err := WriteStructure(donut.file, donutStructure); err != nil {
return err
}
return nil
}
func WriteStructure(target io.Writer, donutStructure DonutStructure) error { return nil }