serenity/AK/Hex.cpp
Liav A 048fb2c204 AK: Disallow returning of string literals for errors in kernel code
This code should not be used in the kernel - we should always propagate
proper errno codes in case we need to return those to userland so it
could decode it in a reasonable way.
2023-02-10 09:14:20 +00:00

59 lines
1.6 KiB
C++

/*
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2022, Sam Atkins <atkinssj@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Hex.h>
#include <AK/StringBuilder.h>
#include <AK/Types.h>
#include <AK/Vector.h>
namespace AK {
ErrorOr<ByteBuffer> decode_hex(StringView input)
{
if ((input.length() % 2) != 0)
return Error::from_string_view_or_print_error_and_return_errno("Hex string was not an even length"sv, EINVAL);
auto output = TRY(ByteBuffer::create_zeroed(input.length() / 2));
for (size_t i = 0; i < input.length() / 2; ++i) {
auto const c1 = decode_hex_digit(input[i * 2]);
if (c1 >= 16)
return Error::from_string_view_or_print_error_and_return_errno("Hex string contains invalid digit"sv, EINVAL);
auto const c2 = decode_hex_digit(input[i * 2 + 1]);
if (c2 >= 16)
return Error::from_string_view_or_print_error_and_return_errno("Hex string contains invalid digit"sv, EINVAL);
output[i] = (c1 << 4) + c2;
}
return { move(output) };
}
#ifdef KERNEL
ErrorOr<NonnullOwnPtr<Kernel::KString>> encode_hex(const ReadonlyBytes input)
{
StringBuilder output(input.size() * 2);
for (auto ch : input)
TRY(output.try_appendff("{:02x}", ch));
return Kernel::KString::try_create(output.string_view());
}
#else
DeprecatedString encode_hex(const ReadonlyBytes input)
{
StringBuilder output(input.size() * 2);
for (auto ch : input)
output.appendff("{:02x}", ch);
return output.to_deprecated_string();
}
#endif
}