ydb/library/cpp/yson/zigzag.h

#pragma once

#include <util/system/defaults.h>

namespace NYson {
    ////////////////////////////////////////////////////////////////////////////////

    //! Functions that provide coding of integers with property: 0 <= f(x) <= 2 * |x|
    //! Actually taken 'as is' from protobuf/wire_format_lite.h

    inline ui32 ZigZagEncode32(i32 n) {
        // Note: the right-shift must be arithmetic
        return (ui32(n) << 1) ^ (n >> 31);
    }

    inline i32 ZigZagDecode32(ui32 n) {
        return (n >> 1) ^ -static_cast<i32>(n & 1);
    }

    inline ui64 ZigZagEncode64(i64 n) {
        // Note: the right-shift must be arithmetic
        return (ui64(n) << 1) ^ (n >> 63);
    }

    inline i64 ZigZagDecode64(ui64 n) {
        return (n >> 1) ^ -static_cast<i64>(n & 1);
    }

    ////////////////////////////////////////////////////////////////////////////////

} // namespace NYson