mirror of https://github.com/jackc/pgx.git
142 lines
2.6 KiB
Go
142 lines
2.6 KiB
Go
package pgtype
|
|
|
|
import (
|
|
"database/sql/driver"
|
|
"encoding/binary"
|
|
"fmt"
|
|
"io"
|
|
|
|
"github.com/jackc/pgx/pgio"
|
|
)
|
|
|
|
type Varbit struct {
|
|
Bytes []byte
|
|
Len int32 // Number of bits
|
|
Status Status
|
|
}
|
|
|
|
func (dst *Varbit) Set(src interface{}) error {
|
|
return fmt.Errorf("cannot convert %v to Varbit", src)
|
|
}
|
|
|
|
func (dst *Varbit) Get() interface{} {
|
|
switch dst.Status {
|
|
case Present:
|
|
return dst
|
|
case Null:
|
|
return nil
|
|
default:
|
|
return dst.Status
|
|
}
|
|
}
|
|
|
|
func (src *Varbit) AssignTo(dst interface{}) error {
|
|
return fmt.Errorf("cannot assign %v to %T", src, dst)
|
|
}
|
|
|
|
func (dst *Varbit) DecodeText(ci *ConnInfo, src []byte) error {
|
|
if src == nil {
|
|
*dst = Varbit{Status: Null}
|
|
return nil
|
|
}
|
|
|
|
bitLen := len(src)
|
|
byteLen := bitLen / 8
|
|
if bitLen%8 > 0 {
|
|
byteLen++
|
|
}
|
|
buf := make([]byte, byteLen)
|
|
|
|
for i, b := range src {
|
|
if b == '1' {
|
|
byteIdx := i / 8
|
|
bitIdx := uint(i % 8)
|
|
buf[byteIdx] = buf[byteIdx] | (128 >> bitIdx)
|
|
}
|
|
}
|
|
|
|
*dst = Varbit{Bytes: buf, Len: int32(bitLen), Status: Present}
|
|
return nil
|
|
}
|
|
|
|
func (dst *Varbit) DecodeBinary(ci *ConnInfo, src []byte) error {
|
|
if src == nil {
|
|
*dst = Varbit{Status: Null}
|
|
return nil
|
|
}
|
|
|
|
if len(src) < 4 {
|
|
return fmt.Errorf("invalid length for varbit: %v", len(src))
|
|
}
|
|
|
|
bitLen := int32(binary.BigEndian.Uint32(src))
|
|
rp := 4
|
|
|
|
buf := make([]byte, len(src[rp:]))
|
|
copy(buf, src[rp:])
|
|
|
|
*dst = Varbit{Bytes: buf, Len: bitLen, Status: Present}
|
|
return nil
|
|
}
|
|
|
|
func (src *Varbit) EncodeText(ci *ConnInfo, w io.Writer) (bool, error) {
|
|
switch src.Status {
|
|
case Null:
|
|
return true, nil
|
|
case Undefined:
|
|
return false, errUndefined
|
|
}
|
|
|
|
buf := make([]byte, int(src.Len))
|
|
for i, _ := range buf {
|
|
byteIdx := i / 8
|
|
bitMask := byte(128 >> byte(i%8))
|
|
char := byte('0')
|
|
if src.Bytes[byteIdx]&bitMask > 0 {
|
|
char = '1'
|
|
}
|
|
buf[i] = char
|
|
}
|
|
|
|
_, err := w.Write(buf)
|
|
return false, err
|
|
}
|
|
|
|
func (src *Varbit) EncodeBinary(ci *ConnInfo, w io.Writer) (bool, error) {
|
|
switch src.Status {
|
|
case Null:
|
|
return true, nil
|
|
case Undefined:
|
|
return false, errUndefined
|
|
}
|
|
|
|
if _, err := pgio.WriteInt32(w, src.Len); err != nil {
|
|
return false, err
|
|
}
|
|
|
|
_, err := w.Write(src.Bytes)
|
|
return false, err
|
|
}
|
|
|
|
// Scan implements the database/sql Scanner interface.
|
|
func (dst *Varbit) Scan(src interface{}) error {
|
|
if src == nil {
|
|
*dst = Varbit{Status: Null}
|
|
return nil
|
|
}
|
|
|
|
switch src := src.(type) {
|
|
case string:
|
|
return dst.DecodeText(nil, []byte(src))
|
|
case []byte:
|
|
return dst.DecodeText(nil, src)
|
|
}
|
|
|
|
return fmt.Errorf("cannot scan %T", src)
|
|
}
|
|
|
|
// Value implements the database/sql/driver Valuer interface.
|
|
func (src *Varbit) Value() (driver.Value, error) {
|
|
return encodeValueText(src)
|
|
}
|