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package pgtype
import (
"database/sql/driver"
"encoding/binary"
"fmt"
"github.com/jackc/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
*dst = Varbit{Bytes: src[rp:], Len: bitLen, Status: Present}
return nil
}
func (src Varbit) EncodeText(ci *ConnInfo, buf []byte) ([]byte, error) {
switch src.Status {
case Null:
return nil, nil
case Undefined:
return nil, errUndefined
}
for i := int32(0); i < src.Len; i++ {
byteIdx := i / 8
bitMask := byte(128 >> byte(i%8))
char := byte('0')
if src.Bytes[byteIdx]&bitMask > 0 {
char = '1'
}
buf = append(buf, char)
}
return buf, nil
}
func (src Varbit) EncodeBinary(ci *ConnInfo, buf []byte) ([]byte, error) {
switch src.Status {
case Null:
return nil, nil
case Undefined:
return nil, errUndefined
}
buf = pgio.AppendInt32(buf, src.Len)
return append(buf, src.Bytes...), nil
}
// 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:
srcCopy := make([]byte, len(src))
copy(srcCopy, src)
return dst.DecodeText(nil, srcCopy)
}
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)
}
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