sysmonitord/internal/scanner/hash/hash.go
wuko233 6cecd69758 [scanner] 实现哈希计算策略
[config] 实现配置转换
2026-03-30 17:19:42 +08:00

93 lines
2.0 KiB
Go

package hash
import (
"crypto/sha256"
"encoding/binary"
"encoding/hex"
"io"
"os"
"sysmonitord/pkg/logger"
"go.uber.org/zap"
)
type Config struct {
UseFastHash bool
Threshold int64
ChunkSize int64
}
func SHA256(filePath string, cfg *Config) (string, error) {
info, err := os.Stat(filePath)
if err != nil {
logger.Log.Warn("[hash]获取文件信息失败", zap.String("path", filePath), zap.Error(err))
return "", err
}
fileSize := info.Size()
if cfg != nil && cfg.UseFastHash && fileSize > cfg.Threshold {
logger.Log.Debug("[hash] 分层哈希...",
zap.String("path", filePath),
zap.Int64("fileSize", fileSize),
)
return calculateFastHash(filePath, fileSize, cfg.ChunkSize)
}
return calculateFullHash(filePath)
}
func calculateFullHash(filePath string) (string, error) {
file, err := os.Open(filePath)
if err != nil {
logger.Log.Warn("[scanner]打开文件失败", zap.String("path", filePath), zap.Error(err))
return "", err
}
defer file.Close()
hasher := sha256.New()
if _, err := io.Copy(hasher, file); err != nil {
logger.Log.Error("[scanner]读取文件失败", zap.String("path", filePath), zap.Error(err))
return "", err
}
hashBytes := hasher.Sum(nil)
hashString := hex.EncodeToString(hashBytes)
return hashString, nil
}
func calculateFastHash(filePath string, fileSize int64, chunkSize int64) (string, error) {
file, err := os.Open(filePath)
if err != nil {
logger.Log.Warn("[scanner]打开文件失败", zap.String("path", filePath), zap.Error(err))
return "", err
}
defer file.Close()
hasher := sha256.New()
if _, err := io.CopyN(hasher, file, chunkSize); err != nil {
if err != io.EOF {
return "", err
}
}
tailOffset := fileSize - chunkSize
if tailOffset < 0 {
tailOffset = 0
}
if _, err := file.Seek(tailOffset, io.SeekStart); err != nil {
return "", err
}
if _, err := io.CopyN(hasher, file, chunkSize); err != nil {
return "", err
}
if err := binary.Write(hasher, binary.BigEndian, fileSize); err != nil {
return "", err
}
return hex.EncodeToString(hasher.Sum(nil)), nil
}