145 lines
3.2 KiB
Go
145 lines
3.2 KiB
Go
/*
|
|
Copyright 2014 SAP SE
|
|
|
|
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 protocol
|
|
|
|
import (
|
|
"fmt"
|
|
|
|
"github.com/SAP/go-hdb/internal/bufio"
|
|
)
|
|
|
|
const (
|
|
partHeaderSize = 16
|
|
)
|
|
|
|
type requestPart interface {
|
|
kind() partKind
|
|
size() (int, error)
|
|
numArg() int
|
|
write(*bufio.Writer) error
|
|
}
|
|
|
|
type replyPart interface {
|
|
//kind() partKind
|
|
setNumArg(int)
|
|
read(*bufio.Reader) error
|
|
}
|
|
|
|
// PartAttributes is an interface defining methods for reading query resultset parts.
|
|
type PartAttributes interface {
|
|
ResultsetClosed() bool
|
|
LastPacket() bool
|
|
NoRows() bool
|
|
}
|
|
|
|
type partAttributes int8
|
|
|
|
const (
|
|
paLastPacket partAttributes = 0x01
|
|
paNextPacket partAttributes = 0x02
|
|
paFirstPacket partAttributes = 0x04
|
|
paRowNotFound partAttributes = 0x08
|
|
paResultsetClosed partAttributes = 0x10
|
|
)
|
|
|
|
var partAttributesText = map[partAttributes]string{
|
|
paLastPacket: "lastPacket",
|
|
paNextPacket: "nextPacket",
|
|
paFirstPacket: "firstPacket",
|
|
paRowNotFound: "rowNotFound",
|
|
paResultsetClosed: "resultsetClosed",
|
|
}
|
|
|
|
func (k partAttributes) String() string {
|
|
t := make([]string, 0, len(partAttributesText))
|
|
|
|
for attr, text := range partAttributesText {
|
|
if (k & attr) != 0 {
|
|
t = append(t, text)
|
|
}
|
|
}
|
|
return fmt.Sprintf("%v", t)
|
|
}
|
|
|
|
func (k partAttributes) ResultsetClosed() bool {
|
|
return (k & paResultsetClosed) == paResultsetClosed
|
|
}
|
|
|
|
func (k partAttributes) LastPacket() bool {
|
|
return (k & paLastPacket) == paLastPacket
|
|
}
|
|
|
|
func (k partAttributes) NoRows() bool {
|
|
attrs := paLastPacket | paRowNotFound
|
|
return (k & attrs) == attrs
|
|
}
|
|
|
|
// part header
|
|
type partHeader struct {
|
|
partKind partKind
|
|
partAttributes partAttributes
|
|
argumentCount int16
|
|
bigArgumentCount int32
|
|
bufferLength int32
|
|
bufferSize int32
|
|
}
|
|
|
|
func (h *partHeader) String() string {
|
|
return fmt.Sprintf("part kind %s partAttributes %s argumentCount %d bigArgumentCount %d bufferLength %d bufferSize %d",
|
|
h.partKind,
|
|
h.partAttributes,
|
|
h.argumentCount,
|
|
h.bigArgumentCount,
|
|
h.bufferLength,
|
|
h.bufferSize,
|
|
)
|
|
}
|
|
|
|
func (h *partHeader) write(wr *bufio.Writer) error {
|
|
wr.WriteInt8(int8(h.partKind))
|
|
wr.WriteInt8(int8(h.partAttributes))
|
|
wr.WriteInt16(h.argumentCount)
|
|
wr.WriteInt32(h.bigArgumentCount)
|
|
wr.WriteInt32(h.bufferLength)
|
|
wr.WriteInt32(h.bufferSize)
|
|
|
|
//no filler
|
|
|
|
if trace {
|
|
outLogger.Printf("write part header: %s", h)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (h *partHeader) read(rd *bufio.Reader) error {
|
|
h.partKind = partKind(rd.ReadInt8())
|
|
h.partAttributes = partAttributes(rd.ReadInt8())
|
|
h.argumentCount = rd.ReadInt16()
|
|
h.bigArgumentCount = rd.ReadInt32()
|
|
h.bufferLength = rd.ReadInt32()
|
|
h.bufferSize = rd.ReadInt32()
|
|
|
|
// no filler
|
|
|
|
if trace {
|
|
outLogger.Printf("read part header: %s", h)
|
|
}
|
|
|
|
return rd.GetError()
|
|
}
|