frostfs-api-go/util/proto/marshal.go

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/*
This package contains help functions for stable marshaller. Their usage is
totally optional. One can implement fast stable marshaller without these
runtime function calls.
*/
package proto
import (
"encoding/binary"
"math/bits"
)
func BytesMarshal(field int, buf, v []byte) (int, error) {
if len(v) == 0 {
return 0, nil
}
// buf length check can prevent panic at PutUvarint, but it will make
// marshaller a bit slower.
prefix := field<<3 | 0x2
i := binary.PutUvarint(buf, uint64(prefix))
i += binary.PutUvarint(buf[i:], uint64(len(v)))
i += copy(buf[i:], v)
return i, nil
}
func BytesSize(field int, v []byte) int {
ln := len(v)
if ln == 0 {
return 0
}
prefix := field<<3 | 0x2
return VarUIntSize(uint64(prefix)) + VarUIntSize(uint64(ln)) + ln
}
func StringMarshal(field int, buf []byte, v string) (int, error) {
return BytesMarshal(field, buf, []byte(v))
}
func StringSize(field int, v string) int {
return BytesSize(field, []byte(v))
}
// varUIntSize returns length of varint byte sequence for uint64 value 'x'.
func VarUIntSize(x uint64) int {
return (bits.Len64(x|1) + 6) / 7
}