1 files changed, 103 insertions, 0 deletions
diff --git a/vendor/github.com/aws/aws-sdk-go/private/protocol/eventstream/message.go b/vendor/github.com/aws/aws-sdk-go/private/protocol/eventstream/message.go
new file mode 100644
index 0000000..2dc012a
--- /dev/null
+++ b/vendor/github.com/aws/aws-sdk-go/private/protocol/eventstream/message.go
@@ -0,0 +1,103 @@
+package eventstream
+
+import (
+	"bytes"
+	"encoding/binary"
+	"hash/crc32"
+)
+
+const preludeLen = 8
+const preludeCRCLen = 4
+const msgCRCLen = 4
+const minMsgLen = preludeLen + preludeCRCLen + msgCRCLen
+const maxPayloadLen = 1024 * 1024 * 16 // 16MB
+const maxHeadersLen = 1024 * 128       // 128KB
+const maxMsgLen = minMsgLen + maxHeadersLen + maxPayloadLen
+
+var crc32IEEETable = crc32.MakeTable(crc32.IEEE)
+
+// A Message provides the eventstream message representation.
+type Message struct {
+	Headers Headers
+	Payload []byte
+}
+
+func (m *Message) rawMessage() (rawMessage, error) {
+	var raw rawMessage
+
+	if len(m.Headers) > 0 {
+		var headers bytes.Buffer
+		if err := encodeHeaders(&headers, m.Headers); err != nil {
+			return rawMessage{}, err
+		}
+		raw.Headers = headers.Bytes()
+		raw.HeadersLen = uint32(len(raw.Headers))
+	}
+
+	raw.Length = raw.HeadersLen + uint32(len(m.Payload)) + minMsgLen
+
+	hash := crc32.New(crc32IEEETable)
+	binaryWriteFields(hash, binary.BigEndian, raw.Length, raw.HeadersLen)
+	raw.PreludeCRC = hash.Sum32()
+
+	binaryWriteFields(hash, binary.BigEndian, raw.PreludeCRC)
+
+	if raw.HeadersLen > 0 {
+		hash.Write(raw.Headers)
+	}
+
+	// Read payload bytes and update hash for it as well.
+	if len(m.Payload) > 0 {
+		raw.Payload = m.Payload
+		hash.Write(raw.Payload)
+	}
+
+	raw.CRC = hash.Sum32()
+
+	return raw, nil
+}
+
+type messagePrelude struct {
+	Length     uint32
+	HeadersLen uint32
+	PreludeCRC uint32
+}
+
+func (p messagePrelude) PayloadLen() uint32 {
+	return p.Length - p.HeadersLen - minMsgLen
+}
+
+func (p messagePrelude) ValidateLens() error {
+	if p.Length == 0 || p.Length > maxMsgLen {
+		return LengthError{
+			Part: "message prelude",
+			Want: maxMsgLen,
+			Have: int(p.Length),
+		}
+	}
+	if p.HeadersLen > maxHeadersLen {
+		return LengthError{
+			Part: "message headers",
+			Want: maxHeadersLen,
+			Have: int(p.HeadersLen),
+		}
+	}
+	if payloadLen := p.PayloadLen(); payloadLen > maxPayloadLen {
+		return LengthError{
+			Part: "message payload",
+			Want: maxPayloadLen,
+			Have: int(payloadLen),
+		}
+	}
+
+	return nil
+}
+
+type rawMessage struct {
+	messagePrelude
+
+	Headers []byte
+	Payload []byte
+
+	CRC uint32
+}