Remove IDSize, TestRandomID -> NewRandomID

src/restic/backend_find.go

@@ -52,8 +52,9 @@ func PrefixLength(be Lister, t FileType) (int, error) {
 	}
 
 	// select prefixes of length l, test if the last one is the same as the current one
+	id := ID{}
 outer:
-	for l := minPrefixLength; l < IDSize; l++ {
+	for l := minPrefixLength; l < len(id); l++ {
 		var last string
 
 		for _, name := range list {
@@ -66,5 +67,5 @@ outer:
 		return l, nil
 	}
 
-	return IDSize, nil
+	return len(id), nil
 }

src/restic/config.go

@@ -1,10 +1,6 @@
 package restic
 
 import (
-	"crypto/rand"
-	"crypto/sha256"
-	"encoding/hex"
-	"io"
 	"testing"
 
 	"github.com/pkg/errors"
@@ -21,9 +17,6 @@ type Config struct {
 	ChunkerPolynomial chunker.Pol `json:"chunker_polynomial"`
 }
 
-// repositoryIDSize is the length of the ID chosen at random for a new repository.
-const repositoryIDSize = sha256.Size
-
 // RepoVersion is the version that is written to the config when a repository
 // is newly created with Init().
 const RepoVersion = 1
@@ -51,13 +44,7 @@ func CreateConfig() (Config, error) {
 		return Config{}, errors.Wrap(err, "chunker.RandomPolynomial")
 	}
 
-	newID := make([]byte, repositoryIDSize)
+	cfg.ID = NewRandomID().String()
-	_, err = io.ReadFull(rand.Reader, newID)
-	if err != nil {
-		return Config{}, errors.Wrap(err, "io.ReadFull")
-	}
-
-	cfg.ID = hex.EncodeToString(newID)
 	cfg.Version = RepoVersion
 
 	debug.Log("Repo.CreateConfig", "New config: %#v", cfg)
@@ -68,13 +55,7 @@ func CreateConfig() (Config, error) {
 func TestCreateConfig(t testing.TB, pol chunker.Pol) (cfg Config) {
 	cfg.ChunkerPolynomial = pol
 
-	newID := make([]byte, repositoryIDSize)
+	cfg.ID = NewRandomID().String()
-	_, err := io.ReadFull(rand.Reader, newID)
-	if err != nil {
-		t.Fatalf("unable to create random ID: %v", err)
-	}
-
-	cfg.ID = hex.EncodeToString(newID)
 	cfg.Version = RepoVersion
 
 	return cfg

src/restic/id.go

@@ -2,9 +2,11 @@ package restic
 
 import (
 	"bytes"
+	"crypto/rand"
 	"crypto/sha256"
 	"encoding/hex"
 	"encoding/json"
+	"io"
 
 	"github.com/pkg/errors"
 )
@@ -14,11 +16,11 @@ func Hash(data []byte) ID {
 	return sha256.Sum256(data)
 }
 
-// IDSize contains the size of an ID, in bytes.
+// idSize contains the size of an ID, in bytes.
-const IDSize = sha256.Size
+const idSize = sha256.Size
 
 // ID references content within a repository.
-type ID [IDSize]byte
+type ID [idSize]byte
 
 // ParseID converts the given string to an ID.
 func ParseID(s string) (ID, error) {
@@ -28,7 +30,7 @@ func ParseID(s string) (ID, error) {
 		return ID{}, errors.Wrap(err, "hex.DecodeString")
 	}
 
-	if len(b) != IDSize {
+	if len(b) != idSize {
 		return ID{}, errors.New("invalid length for hash")
 	}
 
@@ -42,6 +44,17 @@ func (id ID) String() string {
 	return hex.EncodeToString(id[:])
 }
 
+// NewRandomID retuns a randomly generated ID. When reading from rand fails,
+// the function panics.
+func NewRandomID() ID {
+	id := ID{}
+	_, err := io.ReadFull(rand.Reader, id[:])
+	if err != nil {
+		panic(err)
+	}
+	return id
+}
+
 const shortStr = 4
 
 // Str returns the shortened string version of id.

src/restic/pack/pack.go

@@ -50,13 +50,13 @@ func (p *Packer) Add(t restic.BlobType, id restic.ID, data []byte) (int, error)
 	return n, errors.Wrap(err, "Write")
 }
 
-var entrySize = uint(binary.Size(restic.BlobType(0)) + binary.Size(uint32(0)) + restic.IDSize)
+var entrySize = uint(binary.Size(restic.BlobType(0)) + binary.Size(uint32(0)) + len(restic.ID{}))
 
 // headerEntry is used with encoding/binary to read and write header entries
 type headerEntry struct {
 	Type   uint8
 	Length uint32
-	ID     [restic.IDSize]byte
+	ID     restic.ID
 }
 
 // Finalize writes the header for all added blobs and finalizes the pack.

src/restic/pack/pack_test.go

@@ -55,7 +55,7 @@ func verifyBlobs(t testing.TB, bufs []Buf, k *crypto.Key, rd io.ReaderAt, packSi
 	// header length
 	written += binary.Size(uint32(0))
 	// header
-	written += len(bufs) * (binary.Size(restic.BlobType(0)) + binary.Size(uint32(0)) + restic.IDSize)
+	written += len(bufs) * (binary.Size(restic.BlobType(0)) + binary.Size(uint32(0)) + len(restic.ID{}))
 	// header crypto
 	written += crypto.Extension
 

src/restic/repository/index_test.go

@@ -22,11 +22,11 @@ func TestIndexSerialize(t *testing.T) {
 
 	// create 50 packs with 20 blobs each
 	for i := 0; i < 50; i++ {
-		packID := restic.TestRandomID()
+		packID := restic.NewRandomID()
 
 		pos := uint(0)
 		for j := 0; j < 20; j++ {
-			id := restic.TestRandomID()
+			id := restic.NewRandomID()
 			length := uint(i*100 + j)
 			idx.Store(restic.PackedBlob{
 				Blob: restic.Blob{
@@ -94,11 +94,11 @@ func TestIndexSerialize(t *testing.T) {
 	// add more blobs to idx
 	newtests := []testEntry{}
 	for i := 0; i < 10; i++ {
-		packID := restic.TestRandomID()
+		packID := restic.NewRandomID()
 
 		pos := uint(0)
 		for j := 0; j < 10; j++ {
-			id := restic.TestRandomID()
+			id := restic.NewRandomID()
 			length := uint(i*100 + j)
 			idx.Store(restic.PackedBlob{
 				Blob: restic.Blob{
@@ -130,7 +130,7 @@ func TestIndexSerialize(t *testing.T) {
 	Assert(t, idx.Final(),
 		"index not final after encoding")
 
-	id := restic.TestRandomID()
+	id := restic.NewRandomID()
 	OK(t, idx.SetID(id))
 	id2, err := idx.ID()
 	Assert(t, id2.Equal(id),
@@ -167,11 +167,11 @@ func TestIndexSize(t *testing.T) {
 	packs := 200
 	blobs := 100
 	for i := 0; i < packs; i++ {
-		packID := restic.TestRandomID()
+		packID := restic.NewRandomID()
 
 		pos := uint(0)
 		for j := 0; j < blobs; j++ {
-			id := restic.TestRandomID()
+			id := restic.NewRandomID()
 			length := uint(i*100 + j)
 			idx.Store(restic.PackedBlob{
 				Blob: restic.Blob{
@@ -353,11 +353,11 @@ func TestIndexPacks(t *testing.T) {
 	packs := restic.NewIDSet()
 
 	for i := 0; i < 20; i++ {
-		packID := restic.TestRandomID()
+		packID := restic.NewRandomID()
 		idx.Store(restic.PackedBlob{
 			Blob: restic.Blob{
 				Type:   restic.DataBlob,
-				ID:     restic.TestRandomID(),
+				ID:     restic.NewRandomID(),
 				Offset: 0,
 				Length: 23,
 			},

src/restic/testing.go

@@ -1,7 +1,6 @@
 package restic
 
 import (
-	crand "crypto/rand"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -201,14 +200,3 @@ func TestParseID(s string) ID {
 
 	return id
 }
-
-// TestRandomID retuns a randomly generated ID. When reading from rand fails,
-// the function panics.
-func TestRandomID() ID {
-	id := ID{}
-	_, err := io.ReadFull(crand.Reader, id[:])
-	if err != nil {
-		panic(err)
-	}
-	return id
-}