Vendor dependencies

vendor/go.etcd.io/etcd/clientv3/namespace/util.go

@@ -0,0 +1,42 @@
+// Copyright 2017 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package namespace
+
+func prefixInterval(pfx string, key, end []byte) (pfxKey []byte, pfxEnd []byte) {
+	pfxKey = make([]byte, len(pfx)+len(key))
+	copy(pfxKey[copy(pfxKey, pfx):], key)
+
+	if len(end) == 1 && end[0] == 0 {
+		// the edge of the keyspace
+		pfxEnd = make([]byte, len(pfx))
+		copy(pfxEnd, pfx)
+		ok := false
+		for i := len(pfxEnd) - 1; i >= 0; i-- {
+			if pfxEnd[i]++; pfxEnd[i] != 0 {
+				ok = true
+				break
+			}
+		}
+		if !ok {
+			// 0xff..ff => 0x00
+			pfxEnd = []byte{0}
+		}
+	} else if len(end) >= 1 {
+		pfxEnd = make([]byte, len(pfx)+len(end))
+		copy(pfxEnd[copy(pfxEnd, pfx):], end)
+	}
+
+	return pfxKey, pfxEnd
+}