Gibheer
6ea4d2c82d
lib/pq is out of maintenance for some time now, so switch to the newer more active library. Looks like it finally stabilized after a long time.
142 lines
3.1 KiB
Go
142 lines
3.1 KiB
Go
package pgtype
|
|
|
|
import (
|
|
"database/sql/driver"
|
|
"fmt"
|
|
"math"
|
|
)
|
|
|
|
// QCharCodec is for PostgreSQL's special 8-bit-only "char" type more akin to the C
|
|
// language's char type, or Go's byte type. (Note that the name in PostgreSQL
|
|
// itself is "char", in double-quotes, and not char.) It gets used a lot in
|
|
// PostgreSQL's system tables to hold a single ASCII character value (eg
|
|
// pg_class.relkind). It is named Qchar for quoted char to disambiguate from SQL
|
|
// standard type char.
|
|
type QCharCodec struct{}
|
|
|
|
func (QCharCodec) FormatSupported(format int16) bool {
|
|
return format == TextFormatCode || format == BinaryFormatCode
|
|
}
|
|
|
|
func (QCharCodec) PreferredFormat() int16 {
|
|
return BinaryFormatCode
|
|
}
|
|
|
|
func (QCharCodec) PlanEncode(m *Map, oid uint32, format int16, value any) EncodePlan {
|
|
switch format {
|
|
case TextFormatCode, BinaryFormatCode:
|
|
switch value.(type) {
|
|
case byte:
|
|
return encodePlanQcharCodecByte{}
|
|
case rune:
|
|
return encodePlanQcharCodecRune{}
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
type encodePlanQcharCodecByte struct{}
|
|
|
|
func (encodePlanQcharCodecByte) Encode(value any, buf []byte) (newBuf []byte, err error) {
|
|
b := value.(byte)
|
|
buf = append(buf, b)
|
|
return buf, nil
|
|
}
|
|
|
|
type encodePlanQcharCodecRune struct{}
|
|
|
|
func (encodePlanQcharCodecRune) Encode(value any, buf []byte) (newBuf []byte, err error) {
|
|
r := value.(rune)
|
|
if r > math.MaxUint8 {
|
|
return nil, fmt.Errorf(`%v cannot be encoded to "char"`, r)
|
|
}
|
|
b := byte(r)
|
|
buf = append(buf, b)
|
|
return buf, nil
|
|
}
|
|
|
|
func (QCharCodec) PlanScan(m *Map, oid uint32, format int16, target any) ScanPlan {
|
|
switch format {
|
|
case TextFormatCode, BinaryFormatCode:
|
|
switch target.(type) {
|
|
case *byte:
|
|
return scanPlanQcharCodecByte{}
|
|
case *rune:
|
|
return scanPlanQcharCodecRune{}
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
type scanPlanQcharCodecByte struct{}
|
|
|
|
func (scanPlanQcharCodecByte) Scan(src []byte, dst any) error {
|
|
if src == nil {
|
|
return fmt.Errorf("cannot scan NULL into %T", dst)
|
|
}
|
|
|
|
if len(src) > 1 {
|
|
return fmt.Errorf(`invalid length for "char": %v`, len(src))
|
|
}
|
|
|
|
b := dst.(*byte)
|
|
// In the text format the zero value is returned as a zero byte value instead of 0
|
|
if len(src) == 0 {
|
|
*b = 0
|
|
} else {
|
|
*b = src[0]
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
type scanPlanQcharCodecRune struct{}
|
|
|
|
func (scanPlanQcharCodecRune) Scan(src []byte, dst any) error {
|
|
if src == nil {
|
|
return fmt.Errorf("cannot scan NULL into %T", dst)
|
|
}
|
|
|
|
if len(src) > 1 {
|
|
return fmt.Errorf(`invalid length for "char": %v`, len(src))
|
|
}
|
|
|
|
r := dst.(*rune)
|
|
// In the text format the zero value is returned as a zero byte value instead of 0
|
|
if len(src) == 0 {
|
|
*r = 0
|
|
} else {
|
|
*r = rune(src[0])
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (c QCharCodec) DecodeDatabaseSQLValue(m *Map, oid uint32, format int16, src []byte) (driver.Value, error) {
|
|
if src == nil {
|
|
return nil, nil
|
|
}
|
|
|
|
var r rune
|
|
err := codecScan(c, m, oid, format, src, &r)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return string(r), nil
|
|
}
|
|
|
|
func (c QCharCodec) DecodeValue(m *Map, oid uint32, format int16, src []byte) (any, error) {
|
|
if src == nil {
|
|
return nil, nil
|
|
}
|
|
|
|
var r rune
|
|
err := codecScan(c, m, oid, format, src, &r)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return r, nil
|
|
}
|