photoprism/pkg/fs/hash.go

72 lines
1.1 KiB
Go
Raw Normal View History

package fs
import (
"crypto/sha1"
"encoding/hex"
"hash/crc32"
"io"
"os"
)
// Hash returns the SHA1 hash of a file as string.
func Hash(fileName string) string {
var result []byte
file, err := os.Open(fileName)
if err != nil {
return ""
}
defer file.Close()
hash := sha1.New()
if _, err := io.Copy(hash, file); err != nil {
return ""
}
return hex.EncodeToString(hash.Sum(result))
}
// Checksum returns the CRC32 checksum of a file as string.
func Checksum(fileName string) string {
var result []byte
file, err := os.Open(fileName)
if err != nil {
return ""
}
defer file.Close()
hash := crc32.New(crc32.MakeTable(crc32.Castagnoli))
if _, err := io.Copy(hash, file); err != nil {
return ""
}
return hex.EncodeToString(hash.Sum(result))
}
// IsHash tests if a string looks like a hash.
func IsHash(s string) bool {
if s == "" {
return false
}
for _, r := range s {
if (r < 48 || r > 57) && (r < 97 || r > 102) && (r < 65 || r > 70) {
return false
}
}
switch len(s) {
case 8, 16, 32, 40, 56, 64, 80, 128, 256:
return true
}
return false
}