1 files changed, 229 insertions, 0 deletions
diff --git a/codec/marshaler.go b/codec/marshaler.go
new file mode 100644
index 0000000..c6d33a3
--- /dev/null
+++ b/codec/marshaler.go
@@ -0,0 +1,229 @@
+//  Copyright (c) 2020 Cisco and/or its affiliates.
+//
+//  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 codec
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"math"
+	"reflect"
+	"unsafe"
+
+	"github.com/lunixbochs/struc"
+
+	"git.fd.io/govpp.git/api"
+)
+
+var DefaultCodec = &NewCodec{} // &MsgCodec{}
+
+// Marshaler is the interface implemented by the binary API messages that can
+// marshal itself into binary form for the wire.
+type Marshaler interface {
+	Size() int
+	Marshal([]byte) ([]byte, error)
+}
+
+// Unmarshaler is the interface implemented by the binary API messages that can
+// unmarshal a binary representation of itself from the wire.
+type Unmarshaler interface {
+	Unmarshal([]byte) error
+}
+
+type NewCodec struct{}
+
+func (*NewCodec) EncodeMsg(msg api.Message, msgID uint16) (data []byte, err error) {
+	if msg == nil {
+		return nil, errors.New("nil message passed in")
+	}
+	marshaller, ok := msg.(Marshaler)
+	if !ok {
+		return nil, fmt.Errorf("message %s does not implement marshaller", msg.GetMessageName())
+	}
+
+	size := marshaller.Size()
+	offset := getOffset(msg)
+	//fmt.Printf("size=%d offset=%d\n", size, offset)
+
+	b := make([]byte, size+offset)
+	b[0] = byte(msgID >> 8)
+	b[1] = byte(msgID)
+
+	//fmt.Printf("len(b)=%d cap(b)=%d\n", len(b), cap(b))
+	//b = append(b, byte(msgID>>8), byte(msgID))
+
+	//buf := new(bytes.Buffer)
+	//buf.Grow(size)
+
+	// encode msg ID
+	//buf.WriteByte(byte(msgID >> 8))
+	//buf.WriteByte(byte(msgID))
+
+	data, err = marshaller.Marshal(b[offset:])
+	if err != nil {
+		return nil, err
+	}
+	//buf.Write(b)
+
+	return b[0:len(b):len(b)], nil
+}
+
+func getOffset(msg api.Message) (offset int) {
+	switch msg.GetMessageType() {
+	case api.RequestMessage:
+		return 10
+	case api.ReplyMessage:
+		return 6
+	case api.EventMessage:
+		return 6
+	}
+	return 2
+}
+
+func (*NewCodec) DecodeMsg(data []byte, msg api.Message) (err error) {
+	if msg == nil {
+		return errors.New("nil message passed in")
+	}
+	marshaller, ok := msg.(Unmarshaler)
+	if !ok {
+		return fmt.Errorf("message %s does not implement marshaller", msg.GetMessageName())
+	}
+
+	offset := getOffset(msg)
+
+	err = marshaller.Unmarshal(data[offset:len(data)])
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (*NewCodec) DecodeMsgContext(data []byte, msg api.Message) (context uint32, err error) {
+	if msg == nil {
+		return 0, errors.New("nil message passed in")
+	}
+
+	switch msg.GetMessageType() {
+	case api.RequestMessage:
+		return order.Uint32(data[6:10]), nil
+	case api.ReplyMessage:
+		return order.Uint32(data[2:6]), nil
+	}
+
+	return 0, nil
+}
+
+type OldCodec struct{}
+
+func (c *OldCodec) Marshal(v interface{}) (b []byte, err error) {
+	buf := new(bytes.Buffer)
+	if err := struc.Pack(buf, v); err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}
+
+func (c *OldCodec) Unmarshal(data []byte, v interface{}) error {
+	buf := bytes.NewReader(data)
+	if err := struc.Unpack(buf, v); err != nil {
+		return err
+	}
+	return nil
+}
+
+/*type CodecNew struct{}
+
+func (c *CodecNew) Marshal(v interface{}) (b []byte, err error) {
+	buf := new(bytes.Buffer)
+	if err := binary.Write(buf, binary.BigEndian, v); err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}*/
+
+func EncodeBool(b bool) byte {
+	if b {
+		return 1
+	}
+	return 0
+}
+
+func MarshalValue(value interface{}) []byte {
+	switch value.(type) {
+	case int8:
+		return []byte{byte(value.(int8))}
+	case uint8:
+		return []byte{byte(value.(uint8))}
+	}
+	return nil
+}
+
+var order = binary.BigEndian
+
+type Buffer struct {
+	pos int
+	buf []byte
+}
+
+func (b *Buffer) Bytes() []byte {
+	return b.buf[:b.pos]
+}
+
+func (b *Buffer) EncodeUint8(v uint8) {
+	b.buf[b.pos] = v
+	b.pos += 1
+}
+
+func (b *Buffer) EncodeUint16(v uint16) {
+	order.PutUint16(b.buf[b.pos:b.pos+2], v)
+	b.pos += 2
+}
+
+func (b *Buffer) EncodeUint32(v uint32) {
+	order.PutUint32(b.buf[b.pos:b.pos+4], v)
+	b.pos += 4
+}
+
+func (b *Buffer) EncodeUint64(v uint64) {
+	order.PutUint64(b.buf[b.pos:b.pos+8], v)
+	b.pos += 8
+}
+
+func (b *Buffer) EncodeFloat64(v float64) {
+	order.PutUint64(b.buf[b.pos:b.pos+8], math.Float64bits(v))
+	b.pos += 8
+}
+
+func (b *Buffer) EncodeBool(v bool) {
+	if v {
+		b.buf[b.pos] = 1
+	} else {
+		b.buf[b.pos] = 0
+	}
+	b.pos += 1
+}
+
+func (b *Buffer) EncodeString(v string) {
+
+	b.pos += 1
+}
+
+func DecodeString(b []byte) string {
+	sliceHeader := (*reflect.SliceHeader)(unsafe.Pointer(&b))
+	stringHeader := reflect.StringHeader{Data: sliceHeader.Data, Len: sliceHeader.Len}
+	return *(*string)(unsafe.Pointer(&stringHeader))
+}