pgx/pgproto3/parameter_description.go

61 lines
1.4 KiB
Go

package pgproto3
import (
"bytes"
"encoding/binary"
"encoding/json"
)
type ParameterDescription struct {
ParameterOIDs []uint32
}
func (*ParameterDescription) Backend() {}
func (dst *ParameterDescription) UnmarshalBinary(src []byte) error {
buf := bytes.NewBuffer(src)
if buf.Len() < 2 {
return &invalidMessageFormatErr{messageType: "ParameterDescription"}
}
// Reported parameter count will be incorrect when number of args is greater than uint16
buf.Next(2)
// Instead infer parameter count by remaining size of message
parameterCount := buf.Len() / 4
*dst = ParameterDescription{ParameterOIDs: make([]uint32, parameterCount)}
for i := 0; i < parameterCount; i++ {
dst.ParameterOIDs[i] = binary.BigEndian.Uint32(buf.Next(4))
}
return nil
}
func (src *ParameterDescription) MarshalBinary() ([]byte, error) {
var bigEndian BigEndianBuf
buf := &bytes.Buffer{}
buf.WriteByte('t')
buf.Write(bigEndian.Uint32(uint32(4 + 2 + 4*len(src.ParameterOIDs))))
buf.Write(bigEndian.Uint16(uint16(len(src.ParameterOIDs))))
for _, oid := range src.ParameterOIDs {
buf.Write(bigEndian.Uint32(oid))
}
return buf.Bytes(), nil
}
func (src *ParameterDescription) MarshalJSON() ([]byte, error) {
return json.Marshal(struct {
Type string
ParameterOIDs []uint32
}{
Type: "ParameterDescription",
ParameterOIDs: src.ParameterOIDs,
})
}