Files
dolthub--doltgresql/server/types/bit.go
T
2026-07-13 12:32:25 +08:00

97 lines
3.5 KiB
Go

// Copyright 2024 Dolthub, Inc.
//
// 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 types
import (
"github.com/dolthub/go-mysql-server/sql"
"gopkg.in/src-d/go-errors.v1"
"github.com/dolthub/doltgresql/utils"
"github.com/dolthub/doltgresql/core/id"
)
// ErrWrongLengthBit is returned when a value with the incorrect length is inserted into a Bit column.
var ErrWrongLengthBit = errors.NewKind(`bit string length %d does not match type bit(%d)`)
// Bit is a fixed-length bit string.
var Bit = &DoltgresType{
ID: toInternal("bit"),
TypLength: int16(-1),
PassedByVal: false,
TypType: TypeType_Base,
TypCategory: TypeCategory_BitStringTypes,
IsPreferred: false,
IsDefined: true,
Delimiter: ",",
RelID: id.Null,
SubscriptFunc: toFuncID("-"),
Elem: internalNullType,
Array: internalNullType,
InputFunc: toFuncID("bit_in", toInternal("cstring"), toInternal("oid"), toInternal("int4")),
OutputFunc: toFuncID("bit_out", toInternal("bit")),
ReceiveFunc: toFuncID("bit_recv", toInternal("internal"), toInternal("oid"), toInternal("int4")),
SendFunc: toFuncID("bit_send", toInternal("bit")),
ModInFunc: toFuncID("bittypmodin", toInternal("_cstring")),
ModOutFunc: toFuncID("bittypmodout", toInternal("int4")),
AnalyzeFunc: toFuncID("-"),
Align: TypeAlignment_Int,
Storage: TypeStorage_Extended,
NotNull: false,
BaseTypeType: internalNullType,
TypMod: -1,
NDims: 0,
TypCollation: id.NewCollation("pg_catalog", "default"),
DefaulBin: "",
Default: "",
Acl: nil,
Checks: nil,
attTypMod: -1,
CompareFunc: toFuncID("bitcmp", toInternal("bit"), toInternal("bit")),
SerializationFunc: serializeTypeBit,
DeserializationFunc: deserializeTypeBit,
}
// NewBitType returns a Bit type with type modifier set
// representing the number of bits in the string.
func NewBitType(width int32) (*DoltgresType, error) {
if width < 1 {
return nil, ErrLengthMustBeAtLeast1.New("bit")
} else if width > StringMaxLength {
return nil, ErrLengthCannotExceed.New("bit")
}
newType := *Bit.WithAttTypMod(width)
return &newType, nil
}
// serializeTypeBit handles serialization from the standard representation to our serialized representation that is
// written in Dolt.
func serializeTypeBit(ctx *sql.Context, t *DoltgresType, val any) ([]byte, error) {
str := val.(string)
wr := utils.NewWriter(uint64(4 + len(str)))
wr.String(str)
return wr.Data(), nil
}
// deserializeTypeBit handles deserialization from the Dolt serialized format to our standard representation used by
// expressions and nodes.
func deserializeTypeBit(ctx *sql.Context, t *DoltgresType, data []byte) (any, error) {
if len(data) == 0 {
return nil, nil
}
reader := utils.NewReader(data)
return reader.String(), nil
}