Repository navigation
Expand file tree
/
Copy pathbitrot-whole.go
More file actions
109 lines (98 loc) · 3.27 KB
/
Copy pathbitrot-whole.go
File metadata and controls
109 lines (98 loc) · 3.27 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
/*
* Minio Cloud Storage, (C) 2019 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 cmd
import (
"context"
"hash"
"io"
"github.com/minio/minio/cmd/logger"
)
// Implementation to calculate bitrot for the whole file.
type wholeBitrotWriter struct {
disk StorageAPI
volume string
filePath string
shardSize int64 // This is the shard size of the erasure logic
hash.Hash // For bitrot hash
// Following two fields are used only to make sure that Write(p) is called such that
// len(p) is always the block size except the last block and prevent programmer errors.
currentBlockIdx int
lastBlockIdx int
}
func (b *wholeBitrotWriter) Write(p []byte) (int, error) {
if b.currentBlockIdx < b.lastBlockIdx && int64(len(p)) != b.shardSize {
// All blocks except last should be of the length b.shardSize
logger.LogIf(context.Background(), errUnexpected)
return 0, errUnexpected
}
err := b.disk.AppendFile(b.volume, b.filePath, p)
if err != nil {
logger.LogIf(context.Background(), err)
return 0, err
}
_, err = b.Hash.Write(p)
if err != nil {
logger.LogIf(context.Background(), err)
return 0, err
}
b.currentBlockIdx++
return len(p), nil
}
func (b *wholeBitrotWriter) Close() error {
return nil
}
// Returns whole-file bitrot writer.
func newWholeBitrotWriter(disk StorageAPI, volume, filePath string, length int64, algo BitrotAlgorithm, shardSize int64) io.WriteCloser {
return &wholeBitrotWriter{disk, volume, filePath, shardSize, algo.New(), 0, int(length / shardSize)}
}
// Implementation to verify bitrot for the whole file.
type wholeBitrotReader struct {
disk StorageAPI
volume string
filePath string
verifier *BitrotVerifier // Holds the bit-rot info
tillOffset int64 // Affects the length of data requested in disk.ReadFile depending on Read()'s offset
buf []byte // Holds bit-rot verified data
}
func (b *wholeBitrotReader) ReadAt(buf []byte, offset int64) (n int, err error) {
if b.buf == nil {
b.buf = make([]byte, b.tillOffset-offset)
if _, err := b.disk.ReadFile(b.volume, b.filePath, offset, b.buf, b.verifier); err != nil {
ctx := context.Background()
logger.GetReqInfo(ctx).AppendTags("disk", b.disk.String())
logger.LogIf(ctx, err)
return 0, err
}
}
if len(b.buf) < len(buf) {
logger.LogIf(context.Background(), errLessData)
return 0, errLessData
}
n = copy(buf, b.buf)
b.buf = b.buf[n:]
return n, nil
}
// Returns whole-file bitrot reader.
func newWholeBitrotReader(disk StorageAPI, volume, filePath string, algo BitrotAlgorithm, tillOffset int64, sum []byte) *wholeBitrotReader {
return &wholeBitrotReader{
disk: disk,
volume: volume,
filePath: filePath,
verifier: &BitrotVerifier{algo, sum},
tillOffset: tillOffset,
buf: nil,
}
}