1 files changed, 81 insertions, 0 deletions
diff --git a/vendor/github.com/google/gofuzz/bytesource/bytesource.go b/vendor/github.com/google/gofuzz/bytesource/bytesource.go
new file mode 100644
index 000000000..5bb365949
--- /dev/null
+++ b/vendor/github.com/google/gofuzz/bytesource/bytesource.go
@@ -0,0 +1,81 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+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 bytesource provides a rand.Source64 that is determined by a slice of bytes.
+package bytesource
+
+import (
+	"bytes"
+	"encoding/binary"
+	"io"
+	"math/rand"
+)
+
+// ByteSource implements rand.Source64 determined by a slice of bytes. The random numbers are
+// generated from each 8 bytes in the slice, until the last bytes are consumed, from which a
+// fallback pseudo random source is created in case more random numbers are required.
+// It also exposes a `bytes.Reader` API, which lets callers consume the bytes directly.
+type ByteSource struct {
+	*bytes.Reader
+	fallback rand.Source
+}
+
+// New returns a new ByteSource from a given slice of bytes.
+func New(input []byte) *ByteSource {
+	s := &ByteSource{
+		Reader:   bytes.NewReader(input),
+		fallback: rand.NewSource(0),
+	}
+	if len(input) > 0 {
+		s.fallback = rand.NewSource(int64(s.consumeUint64()))
+	}
+	return s
+}
+
+func (s *ByteSource) Uint64() uint64 {
+	// Return from input if it was not exhausted.
+	if s.Len() > 0 {
+		return s.consumeUint64()
+	}
+
+	// Input was exhausted, return random number from fallback (in this case fallback should not be
+	// nil). Try first having a Uint64 output (Should work in current rand implementation),
+	// otherwise return a conversion of Int63.
+	if s64, ok := s.fallback.(rand.Source64); ok {
+		return s64.Uint64()
+	}
+	return uint64(s.fallback.Int63())
+}
+
+func (s *ByteSource) Int63() int64 {
+	return int64(s.Uint64() >> 1)
+}
+
+func (s *ByteSource) Seed(seed int64) {
+	s.fallback = rand.NewSource(seed)
+	s.Reader = bytes.NewReader(nil)
+}
+
+// consumeUint64 reads 8 bytes from the input and convert them to a uint64. It assumes that the the
+// bytes reader is not empty.
+func (s *ByteSource) consumeUint64() uint64 {
+	var bytes [8]byte
+	_, err := s.Read(bytes[:])
+	if err != nil && err != io.EOF {
+		panic("failed reading source") // Should not happen.
+	}
+	return binary.BigEndian.Uint64(bytes[:])
+}