imgsrv/hash/hash.go

package hash

import (
	"crypto/md5"
	"fmt"
	"hash/adler32"
	"io"
	"math/rand"
	"time"
)

func Rand64() int64 {
	return rand.Int63()
}

/* Convinience method for getting md5 sum of a string */
func GetMd5FromString(blob string) (sum []byte) {
	h := md5.New()
	defer h.Reset()
	io.WriteString(h, blob)
	return h.Sum(nil)
}

/* Convinience method for getting md5 sum of some bytes */
func GetMd5FromBytes(blob []byte) (sum []byte) {
	h := md5.New()
	defer h.Reset()
	h.Write(blob)
	return h.Sum(nil)
}

/* get a small, decently unique hash */
func GetSmallHash() (small_hash string) {
	h := adler32.New()
	io.WriteString(h, fmt.Sprintf("%d", time.Now().Unix()))
	return fmt.Sprintf("%X", h.Sum(nil))
}