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//go:build (amd64 || arm64 || riscv64) && !purego
package proto
import (
"unsafe"
"github.com/go-faster/errors"
"github.com/google/uuid"
"github.com/segmentio/asm/bswap"
)
func (c *ColUUID) DecodeColumn(r *Reader, rows int) error {
if rows == 0 {
return nil
}
*c = append(*c, make([]uuid.UUID, rows)...)
// Memory layout of [N]UUID is same as [N*sizeof(UUID)]byte.
// So just interpret c as byte slice and read data into it.
s := *(*slice)(unsafe.Pointer(c)) // #nosec: G103 // memory layout matches
const size = 16
s.Len *= size
s.Cap *= size
dst := *(*[]byte)(unsafe.Pointer(&s)) // #nosec: G103 // memory layout matches
if err := r.ReadFull(dst); err != nil {
return errors.Wrap(err, "read full")
}
bswap.Swap64(dst) // BE <-> LE
return nil
}
// EncodeColumn encodes ColUUID rows to *Buffer.
func (c ColUUID) EncodeColumn(b *Buffer) {
if len(c) == 0 {
return
}
offset := len(b.Buf)
const size = 16
b.Buf = append(b.Buf, make([]byte, size*len(c))...)
s := *(*slice)(unsafe.Pointer(&c)) // #nosec: G103 // memory layout matches
s.Len *= size
s.Cap *= size
src := *(*[]byte)(unsafe.Pointer(&s)) // #nosec: G103 // memory layout matches
dst := b.Buf[offset:]
copy(dst, src)
bswap.Swap64(dst) // BE <-> LE
}
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