blob: 82d185616742c0f0ea92e882e8b2efe5cc2fa2dc (
plain) (
blame)
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
|
// package hash provides a way for managing the
// underlying hash implementations used across go-git.
package hash
import (
"crypto"
"fmt"
"hash"
"github.com/pjbgf/sha1cd"
)
// algos is a map of hash algorithms.
var algos = map[crypto.Hash]func() hash.Hash{}
func init() {
reset()
}
// reset resets the default algos value. Can be used after running tests
// that registers new algorithms to avoid side effects.
func reset() {
algos[crypto.SHA1] = sha1cd.New
algos[crypto.SHA256] = crypto.SHA256.New
}
// RegisterHash allows for the hash algorithm used to be overriden.
// This ensures the hash selection for go-git must be explicit, when
// overriding the default value.
func RegisterHash(h crypto.Hash, f func() hash.Hash) error {
if f == nil {
return fmt.Errorf("cannot register hash: f is nil")
}
switch h {
case crypto.SHA1:
algos[h] = f
case crypto.SHA256:
algos[h] = f
default:
return fmt.Errorf("unsupported hash function: %v", h)
}
return nil
}
// Hash is the same as hash.Hash. This allows consumers
// to not having to import this package alongside "hash".
type Hash interface {
hash.Hash
}
// New returns a new Hash for the given hash function.
// It panics if the hash function is not registered.
func New(h crypto.Hash) Hash {
hh, ok := algos[h]
if !ok {
panic(fmt.Sprintf("hash algorithm not registered: %v", h))
}
return hh()
}
|
