bw.Close()
			}
		}
	}
}

// Returns hash sum for whole-bitrot, nil for streaming-bitrot.
func bitrotWriterSum(w io.Writer) []byte {
	if bw, ok := w.(*wholeBitrotWriter); ok {
		return bw.Sum(nil)
	}
	return nil
}

// Returns the size of the file with bitrot protection
func bitrotShardFileSize(size int64, shardSize int64, algo BitrotAlgorithm) int64 {

// newStreamingBitrotWriterBuffer returns streaming bitrot writer implementation.
// The output is written to the supplied writer w.
func newStreamingBitrotWriterBuffer(w io.Writer, algo BitrotAlgorithm, shardSize int64) io.Writer {
	return &streamingBitrotWriter{iow: ioutil.NopCloser(w), h: algo.New(), shardSize: shardSize, canClose: nil, closeWithErr: func(err error) {}}
}

// Returns streaming bitrot writer implementation.

package cmd

import (
	"context"
	"hash"
	"io"
)

// 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
}

func (b *wholeBitrotWriter) Write(p []byte) (int, error) {

	if err = config.CheckValidKeys(config.HealSubSys, kvs, DefaultKVS); err != nil {
		return cfg, err
	}

	bitrot := env.Get(EnvBitrot, kvs.GetWithDefault(Bitrot, DefaultKVS))
	if _, err = parseBitrotConfig(bitrot); err != nil {
		return cfg, fmt.Errorf("'heal:bitrotscan' value invalid: %w", err)
	}

	cfg.Bitrot = bitrot

	cfg.Sleep, err = time.ParseDuration(env.Get(EnvSleep, kvs.GetWithDefault(Sleep, DefaultKVS)))
	if err != nil {

	ModTime time.Time `json:"modTime"` // ModTime of the object `xl.meta`.
	Name    string    `json:"name"`
	Dir     bool      `json:"dir"`
	Mode    uint32    `json:"mode"`
}

// ErasureInfo holds erasure coding and bitrot related information.
type ErasureInfo struct {
	// Algorithm is the string representation of erasure-coding-algorithm
	Algorithm string `json:"algorithm"`
	// DataBlocks is the number of data blocks for erasure-coding

		return config.DefaultHelpPostfix(DefaultKVS, key)
	}

	// Help provides help for config values
	Help = config.HelpKVS{
		config.HelpKV{
			Key:         Bitrot,
			Description: `perform bitrot scan on drives when checking objects during scanner` + defaultHelpPostfix(Bitrot),
			Optional:    true,
			Type:        "on|off",
		},
		config.HelpKV{
			Key:         Sleep,

		}
	}
}

// Test xlStorage.VerifyFile()
func TestXLStorageVerifyFile(t *testing.T) {
	// We test 4 cases:
	// 1) Whole-file bitrot check on proper file
	// 2) Whole-file bitrot check on corrupted file
	// 3) Streaming bitrot check on proper file
	// 4) Streaming bitrot check on corrupted file

	// create xlStorage test setup
	storage, path, err := newXLStorageTestSetup(t)
	if err != nil {

```
~ mc admin config set alias/ heal
KEY:
heal  manage object healing frequency and bitrot verification checks

ARGS:
bitrotscan     (on|off)    perform bitrot scan on drives when checking objects during scanner
max_sleep      (duration)  maximum sleep duration between objects to slow down heal operation. eg. 2s

				verified++
			}
		}
	}
	fmt.Println("Reconstructed", reconstructed, "bytes and verified", verified, "bytes of partial shard with config", shardConfig)
}

// bitrot returns a shard beginning at startOffset after doing bitrot checks.
func bitrot(val []byte, startOffset, shardSize int) ([]byte, error) {
	var res []byte
	for len(val) >= 32 {
		want := val[:32]
		data := val[32:]
		if len(data) > shardSize {

					f, err := os.OpenFile(filePath, os.O_WRONLY|os.O_SYNC, 0)
					if err != nil {
						t.Fatalf("Failed to open %s: %s\n", filePath, err)
					}
					f.WriteString("oops") // Will cause bitrot error
					f.Close()
					break
				}

			}

			rQuorum := len(errs) - z.serverPools[0].sets[0].defaultParityCount