Merge pull request #286 from thinxer/parseKeyHash

faster ParseKeyHash

go/storage/needle.go

@@ -1,7 +1,6 @@
 package storage
 
 import (
-	"encoding/hex"
 	"errors"
 	"fmt"
 	"io/ioutil"
@@ -15,7 +14,6 @@ import (
 	"github.com/chrislusf/seaweedfs/go/glog"
 	"github.com/chrislusf/seaweedfs/go/images"
 	"github.com/chrislusf/seaweedfs/go/operation"
-	"github.com/chrislusf/seaweedfs/go/util"
 )
 
 const (
@@ -213,16 +211,25 @@ func (n *Needle) ParsePath(fid string) (err error) {
 }
 
 func ParseKeyHash(key_hash_string string) (uint64, uint32, error) {
-	if len(key_hash_string)%2 == 1 {
-		key_hash_string = "0" + key_hash_string
-	}
-	key_hash_bytes, khe := hex.DecodeString(key_hash_string)
-	key_hash_len := len(key_hash_bytes)
-	if khe != nil || key_hash_len <= 4 {
-		glog.V(0).Infoln("Invalid key_hash", key_hash_string, "length:", key_hash_len, "error", khe)
+	key, hash, ok := parseKeyHash(key_hash_string)
+	if !ok {
 		return 0, 0, errors.New("Invalid key and hash:" + key_hash_string)
 	}
-	key := util.BytesToUint64(key_hash_bytes[0 : key_hash_len-4])
-	hash := util.BytesToUint32(key_hash_bytes[key_hash_len-4 : key_hash_len])
 	return key, hash, nil
 }
+
+func parseKeyHash(keyhash string) (uint64, uint32, bool) {
+	if len(keyhash) <= 8 || len(keyhash) > 24 {
+		return 0, 0, false
+	}
+	split := len(keyhash) - 8
+	key, err := strconv.ParseUint(keyhash[:split], 16, 64)
+	if err != nil {
+		return 0, 0, false
+	}
+	hash, err := strconv.ParseUint(keyhash[split:], 16, 32)
+	if err != nil {
+		return 0, 0, false
+	}
+	return key, uint32(hash), true
+}

go/storage/needle_test.go

@@ -0,0 +1,45 @@
+package storage
+
+import "testing"
+
+func TestParseKeyHash(t *testing.T) {
+	testcases := []struct {
+		KeyHash string
+		ID      uint64
+		Cookie  uint32
+		Err     bool
+	}{
+		// normal
+		{"4ed4c8116e41", 0x4ed4, 0xc8116e41, false},
+		// cookie with leading zeros
+		{"4ed401116e41", 0x4ed4, 0x01116e41, false},
+		// odd length
+		{"ed400116e41", 0xed4, 0x00116e41, false},
+		// uint
+		{"fed4c8114ed4c811f0116e41", 0xfed4c8114ed4c811, 0xf0116e41, false},
+		// err: too short
+		{"4ed4c811", 0, 0, true},
+		// err: too long
+		{"4ed4c8114ed4c8114ed4c8111", 0, 0, true},
+		// err: invalid character
+		{"helloworld", 0, 0, true},
+	}
+
+	for _, tc := range testcases {
+		if id, cookie, err := ParseKeyHash(tc.KeyHash); err != nil && !tc.Err {
+			t.Fatalf("Parse %s error: %v", tc.KeyHash, err)
+		} else if err == nil && tc.Err {
+			t.Fatalf("Parse %s expected error got nil", tc.KeyHash)
+		} else if id != tc.ID || cookie != tc.Cookie {
+			t.Fatalf("Parse %s wrong result. Expected: (%d, %d) got: (%d, %d)", tc.KeyHash, tc.ID, tc.Cookie, id, cookie)
+		}
+	}
+}
+
+func BenchmarkParseKeyHash(b *testing.B) {
+	b.ReportAllocs()
+
+	for i := 0; i < b.N; i++ {
+		ParseKeyHash("4ed44ed44ed44ed4c8116e41")
+	}
+}