1 files changed, 114 insertions, 0 deletions
diff --git a/vendor/github.com/aws/aws-sdk-go/private/protocol/eventstream/encode.go b/vendor/github.com/aws/aws-sdk-go/private/protocol/eventstream/encode.go
new file mode 100644
index 0000000..150a609
--- /dev/null
+++ b/vendor/github.com/aws/aws-sdk-go/private/protocol/eventstream/encode.go
@@ -0,0 +1,114 @@
+package eventstream
+
+import (
+	"bytes"
+	"encoding/binary"
+	"hash"
+	"hash/crc32"
+	"io"
+)
+
+// Encoder provides EventStream message encoding.
+type Encoder struct {
+	w io.Writer
+
+	headersBuf *bytes.Buffer
+}
+
+// NewEncoder initializes and returns an Encoder to encode Event Stream
+// messages to an io.Writer.
+func NewEncoder(w io.Writer) *Encoder {
+	return &Encoder{
+		w:          w,
+		headersBuf: bytes.NewBuffer(nil),
+	}
+}
+
+// Encode encodes a single EventStream message to the io.Writer the Encoder
+// was created with. An error is returned if writing the message fails.
+func (e *Encoder) Encode(msg Message) error {
+	e.headersBuf.Reset()
+
+	err := encodeHeaders(e.headersBuf, msg.Headers)
+	if err != nil {
+		return err
+	}
+
+	crc := crc32.New(crc32IEEETable)
+	hashWriter := io.MultiWriter(e.w, crc)
+
+	headersLen := uint32(e.headersBuf.Len())
+	payloadLen := uint32(len(msg.Payload))
+
+	if err := encodePrelude(hashWriter, crc, headersLen, payloadLen); err != nil {
+		return err
+	}
+
+	if headersLen > 0 {
+		if _, err := io.Copy(hashWriter, e.headersBuf); err != nil {
+			return err
+		}
+	}
+
+	if payloadLen > 0 {
+		if _, err := hashWriter.Write(msg.Payload); err != nil {
+			return err
+		}
+	}
+
+	msgCRC := crc.Sum32()
+	return binary.Write(e.w, binary.BigEndian, msgCRC)
+}
+
+func encodePrelude(w io.Writer, crc hash.Hash32, headersLen, payloadLen uint32) error {
+	p := messagePrelude{
+		Length:     minMsgLen + headersLen + payloadLen,
+		HeadersLen: headersLen,
+	}
+	if err := p.ValidateLens(); err != nil {
+		return err
+	}
+
+	err := binaryWriteFields(w, binary.BigEndian,
+		p.Length,
+		p.HeadersLen,
+	)
+	if err != nil {
+		return err
+	}
+
+	p.PreludeCRC = crc.Sum32()
+	err = binary.Write(w, binary.BigEndian, p.PreludeCRC)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func encodeHeaders(w io.Writer, headers Headers) error {
+	for _, h := range headers {
+		hn := headerName{
+			Len: uint8(len(h.Name)),
+		}
+		copy(hn.Name[:hn.Len], h.Name)
+		if err := hn.encode(w); err != nil {
+			return err
+		}
+
+		if err := h.Value.encode(w); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func binaryWriteFields(w io.Writer, order binary.ByteOrder, vs ...interface{}) error {
+	for _, v := range vs {
+		if err := binary.Write(w, order, v); err != nil {
+			return err
+		}
+	}
+	return nil
+}