Files
xahaud/include/xrpl/protocol/Serializer.h
Alphonse Mousse 1f575aa3f6 Improve base_uint:
This commit makes several changes to the base_uint class, which was
originally taken from Bitcoin and has already been heavily modified
by Ripple engineers.

It introduces conditional widening of the internal limb type, going
from 32 to 64 bits if the requested number of bits is a multiple of
64. This change alone halves iteration counts for common operations
and, combined with use of add-with-carry compiler intrinsics, helps
leverage modern processor resources more effectively.

Other changes include:

 - Extracting the arithmetic operations into free helper functions
   which operate on the limb array directly.
 - Replacing the SFINAE-based is_contiguous_container trait with a
   byte_copy_source concept.
 - Rewriting the hex parsing around a consteval lookup table and a
   simple left-to-right loop, replacing the old shift-based nibble
   accumulator.
 - Using memmove instead of memcpy when copying to avoid UB in the
   unlikely case where the source and destination buffers overlap.
 - Eliminating a workaround in operator<=> to handle MacOS quirks.
 - Removing redundant parseHex overloads and introducing from_hex
   as a factory function.
 - Introducing a tagless_compare() for cross-tag comparison.
 - Adding noexcept, [[nodiscard]], and constexpr throughout.
2026-09-23 13:03:28 +10:00

478 lines
9.9 KiB
C++

//------------------------------------------------------------------------------
/*
This file is part of rippled: https://github.com/ripple/rippled
Copyright (c) 2012, 2013 Ripple Labs Inc.
Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL , DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================
#ifndef RIPPLE_PROTOCOL_SERIALIZER_H_INCLUDED
#define RIPPLE_PROTOCOL_SERIALIZER_H_INCLUDED
#include <xrpl/basics/Blob.h>
#include <xrpl/basics/Buffer.h>
#include <xrpl/basics/Slice.h>
#include <xrpl/basics/base_uint.h>
#include <xrpl/basics/contract.h>
#include <xrpl/basics/safe_cast.h>
#include <xrpl/basics/strHex.h>
#include <xrpl/beast/utility/instrumentation.h>
#include <xrpl/protocol/HashPrefix.h>
#include <xrpl/protocol/SField.h>
#include <cstdint>
#include <cstring>
#include <iomanip>
#include <type_traits>
namespace ripple {
class Serializer
{
private:
// DEPRECATED
Blob mData;
public:
explicit Serializer(int n = 256)
{
mData.reserve(n);
}
Serializer(void const* data, std::size_t size)
{
mData.resize(size);
if (size)
{
XRPL_ASSERT(
data,
"ripple::Serializer::Serializer(void const*) : non-null input");
std::memcpy(mData.data(), data, size);
}
}
Slice
slice() const noexcept
{
return Slice(mData.data(), mData.size());
}
std::size_t
size() const noexcept
{
return mData.size();
}
void const*
data() const noexcept
{
return mData.data();
}
// assemble functions
int
add8(unsigned char i);
int
add16(std::uint16_t i);
template <typename T>
requires(std::is_same_v<
std::make_unsigned_t<std::remove_cv_t<T>>,
std::uint32_t>)
int
add32(T i)
{
int ret = mData.size();
mData.push_back(static_cast<unsigned char>((i >> 24) & 0xff));
mData.push_back(static_cast<unsigned char>((i >> 16) & 0xff));
mData.push_back(static_cast<unsigned char>((i >> 8) & 0xff));
mData.push_back(static_cast<unsigned char>(i & 0xff));
return ret;
}
int
add32(HashPrefix p);
template <typename T>
requires(std::is_same_v<
std::make_unsigned_t<std::remove_cv_t<T>>,
std::uint64_t>)
int
add64(T i)
{
int ret = mData.size();
mData.push_back(static_cast<unsigned char>((i >> 56) & 0xff));
mData.push_back(static_cast<unsigned char>((i >> 48) & 0xff));
mData.push_back(static_cast<unsigned char>((i >> 40) & 0xff));
mData.push_back(static_cast<unsigned char>((i >> 32) & 0xff));
mData.push_back(static_cast<unsigned char>((i >> 24) & 0xff));
mData.push_back(static_cast<unsigned char>((i >> 16) & 0xff));
mData.push_back(static_cast<unsigned char>((i >> 8) & 0xff));
mData.push_back(static_cast<unsigned char>(i & 0xff));
return ret;
}
template <typename Integer>
int addInteger(Integer);
template <std::size_t Bits, class Tag>
int
addBitString(base_uint<Bits, Tag> const& v)
{
return addRaw(v.data(), v.size());
}
int
addRaw(Blob const& vector);
int
addRaw(Slice slice);
int
addRaw(const void* ptr, int len);
int
addRaw(const Serializer& s);
int
addVL(Blob const& vector);
int
addVL(Slice const& slice);
template <class Iter>
int
addVL(Iter begin, Iter end, int len);
int
addVL(const void* ptr, int len);
// disassemble functions
bool
get8(int&, int offset) const;
template <typename Integer>
bool
getInteger(Integer& number, int offset)
{
static const auto bytes = sizeof(Integer);
if ((offset + bytes) > mData.size())
return false;
number = 0;
auto ptr = &mData[offset];
for (auto i = 0; i < bytes; ++i)
{
if (i)
number <<= 8;
number |= *ptr++;
}
return true;
}
template <std::size_t Bits, typename Tag = void>
bool
getBitString(base_uint<Bits, Tag>& data, int offset) const
{
auto success = (offset + (Bits / 8)) <= mData.size();
if (success)
memcpy(data.begin(), &(mData.front()) + offset, (Bits / 8));
return success;
}
int
addFieldID(int type, int name);
int
addFieldID(SerializedTypeID type, int name)
{
return addFieldID(safe_cast<int>(type), name);
}
// DEPRECATED
uint256
getSHA512Half() const;
// totality functions
Blob const&
peekData() const
{
return mData;
}
Blob
getData() const
{
return mData;
}
Blob&
modData()
{
return mData;
}
int
getDataLength() const
{
return mData.size();
}
const void*
getDataPtr() const
{
return mData.data();
}
void*
getDataPtr()
{
return mData.data();
}
int
getLength() const
{
return mData.size();
}
std::string
getString() const
{
return std::string(static_cast<const char*>(getDataPtr()), size());
}
void
erase()
{
mData.clear();
}
bool
chop(int num);
// vector-like functions
Blob ::iterator
begin()
{
return mData.begin();
}
Blob ::iterator
end()
{
return mData.end();
}
Blob ::const_iterator
begin() const
{
return mData.begin();
}
Blob ::const_iterator
end() const
{
return mData.end();
}
void
reserve(size_t n)
{
mData.reserve(n);
}
void
resize(size_t n)
{
mData.resize(n);
}
size_t
capacity() const
{
return mData.capacity();
}
bool
operator==(Blob const& v) const
{
return v == mData;
}
bool
operator!=(Blob const& v) const
{
return v != mData;
}
bool
operator==(const Serializer& v) const
{
return v.mData == mData;
}
bool
operator!=(const Serializer& v) const
{
return v.mData != mData;
}
static int
decodeLengthLength(int b1);
static int
decodeVLLength(int b1);
static int
decodeVLLength(int b1, int b2);
static int
decodeVLLength(int b1, int b2, int b3);
private:
static int
encodeLengthLength(int length); // length to encode length
int
addEncoded(int length);
};
template <class Iter>
int
Serializer::addVL(Iter begin, Iter end, int len)
{
int ret = addEncoded(len);
for (; begin != end; ++begin)
{
addRaw(begin->data(), begin->size());
#ifndef NDEBUG
len -= begin->size();
#endif
}
XRPL_ASSERT(
len == 0, "ripple::Serializer::addVL : length matches distance");
return ret;
}
//------------------------------------------------------------------------------
// DEPRECATED
// Transitional adapter to new serialization interfaces
class SerialIter
{
private:
std::uint8_t const* p_;
std::size_t remain_;
std::size_t used_ = 0;
public:
SerialIter(void const* data, std::size_t size) noexcept;
SerialIter(Slice const& slice) : SerialIter(slice.data(), slice.size())
{
}
// Infer the size of the data based on the size of the passed array.
template <int N>
explicit SerialIter(std::uint8_t const (&data)[N]) : SerialIter(&data[0], N)
{
static_assert(N > 0, "");
}
std::size_t
empty() const noexcept
{
return remain_ == 0;
}
void
reset() noexcept;
int
getBytesLeft() const noexcept
{
return static_cast<int>(remain_);
}
// get functions throw on error
unsigned char
get8();
std::uint16_t
get16();
std::uint32_t
get32();
std::int32_t
geti32();
std::uint64_t
get64();
std::int64_t
geti64();
template <std::size_t Bits, class Tag = void>
base_uint<Bits, Tag>
getBitString();
uint128
get128()
{
return getBitString<128>();
}
uint160
get160()
{
return getBitString<160>();
}
uint192
get192()
{
return getBitString<192>();
}
uint256
get256()
{
return getBitString<256>();
}
void
getFieldID(int& type, int& name);
// Returns the size of the VL if the
// next object is a VL. Advances the iterator
// to the beginning of the VL.
int
getVLDataLength();
Slice
getSlice(std::size_t bytes);
// VFALCO DEPRECATED Returns a copy
Blob
getRaw(int size);
// VFALCO DEPRECATED Returns a copy
Blob
getVL();
void
skip(int num);
Buffer
getVLBuffer();
template <class T>
T
getRawHelper(int size);
};
template <std::size_t Bits, class Tag>
base_uint<Bits, Tag>
SerialIter::getBitString()
{
auto constexpr N = base_uint<Bits, Tag>::bytes;
if (remain_ < N)
Throw<std::runtime_error>("invalid SerialIter getBitString");
auto const x = p_;
p_ += N;
used_ += N;
remain_ -= N;
return base_uint<Bits, Tag>(std::span<uint8_t const, N>{x, N});
}
} // namespace ripple
#endif