ByteBuffer.h

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/*
 * This file is part of the TrinityCore Project. See AUTHORS file for Copyright information
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program. If not, see <http://www.gnu.org/licenses/>.
 */
 
#ifndef _BYTEBUFFER_H
#define _BYTEBUFFER_H
 
#include "Define.h"
#include "ByteConverter.h"
#include <array>
#include <string>
#include <vector>
#include <cstring>
 
class MessageBuffer;
 
// Root of ByteBuffer exception hierarchy
class TC_SHARED_API ByteBufferException : public std::exception
{
public:
 ~ByteBufferException() noexcept = default;
 
 char const* what() const noexcept override { return msg_.c_str(); }
 
protected:
 std::string & message() noexcept { return msg_; }
 
private:
 std::string msg_;
};
 
class TC_SHARED_API ByteBufferPositionException : public ByteBufferException
{
public:
 ByteBufferPositionException(size_t pos, size_t size, size_t valueSize);
 
 ~ByteBufferPositionException() noexcept = default;
};
 
class TC_SHARED_API ByteBufferInvalidValueException : public ByteBufferException
{
public:
 ByteBufferInvalidValueException(char const* type, char const* value);
 
 ~ByteBufferInvalidValueException() noexcept = default;
};
 
class TC_SHARED_API ByteBuffer
{
 public:
 constexpr static size_t DEFAULT_SIZE = 0x1000;
 constexpr static uint8 InitialBitPos = 8;
 
 // constructor
 ByteBuffer() : _rpos(0), _wpos(0), _bitpos(InitialBitPos), _curbitval(0)
 {
 _storage.reserve(DEFAULT_SIZE);
 }
 
 // reserve/resize tag
 struct Reserve { };
 struct Resize { };
 
 ByteBuffer(size_t size, Reserve) : _rpos(0), _wpos(0), _bitpos(InitialBitPos), _curbitval(0)
 {
 _storage.reserve(size);
 }
 
 ByteBuffer(size_t size, Resize) : _rpos(0), _wpos(size), _bitpos(InitialBitPos), _curbitval(0)
 {
 _storage.resize(size);
 }
 
 ByteBuffer(ByteBuffer&& buf) noexcept : _rpos(buf._rpos), _wpos(buf._wpos),
 _bitpos(buf._bitpos), _curbitval(buf._curbitval), _storage(buf.Move()) { }
 
 ByteBuffer(ByteBuffer const& right) = default;
 
 ByteBuffer(MessageBuffer&& buffer);
 
 std::vector<uint8>&& Move() noexcept
 {
 _rpos = 0;
 _wpos = 0;
 _bitpos = InitialBitPos;
 _curbitval = 0;
 return std::move(_storage);
 }
 
 ByteBuffer& operator=(ByteBuffer const& right)
 {
 if (this != &right)
 {
 _rpos = right._rpos;
 _wpos = right._wpos;
 _bitpos = right._bitpos;
 _curbitval = right._curbitval;
 _storage = right._storage;
 }
 
 return *this;
 }
 
 ByteBuffer& operator=(ByteBuffer&& right) noexcept
 {
 if (this != &right)
 {
 _rpos = right._rpos;
 _wpos = right._wpos;
 _bitpos = right._bitpos;
 _curbitval = right._curbitval;
 _storage = right.Move();
 }
 
 return *this;
 }
 
 virtual ~ByteBuffer() = default;
 
 void clear()
 {
 _rpos = 0;
 _wpos = 0;
 _bitpos = InitialBitPos;
 _curbitval = 0;
 _storage.clear();
 }
 
 template <typename T>
 void append(T value)
 {
 static_assert(std::is_trivially_copyable<T>::value, "append(T) must be used with trivially copyable types");
 EndianConvert(value);
 append((uint8 *)&value, sizeof(value));
 }
 
 bool HasUnfinishedBitPack() const
 {
 return _bitpos != 8;
 }
 
 void FlushBits()
 {
 if (_bitpos == 8)
 return;
 
 _bitpos = 8;
 
 append((uint8 *)&_curbitval, sizeof(uint8));
 _curbitval = 0;
 }
 
 void ResetBitPos()
 {
 if (_bitpos > 7)
 return;
 
 _bitpos = 8;
 _curbitval = 0;
 }
 
 bool WriteBit(bool bit)
 {
 --_bitpos;
 if (bit)
 _curbitval |= (1 << (_bitpos));
 
 if (_bitpos == 0)
 {
 _bitpos = 8;
 append((uint8 *)&_curbitval, sizeof(_curbitval));
 _curbitval = 0;
 }
 
 return bit;
 }
 
 bool ReadBit()
 {
 ++_bitpos;
 if (_bitpos > 7)
 {
 _curbitval = read<uint8>();
 _bitpos = 0;
 }
 
 return ((_curbitval >> (7-_bitpos)) & 1) != 0;
 }
 
 void WriteBits(std::size_t value, int32 bits)
 {
 for (int32 i = bits - 1; i >= 0; --i)
 WriteBit((value >> i) & 1);
 }
 
 uint32 ReadBits(int32 bits)
 {
 uint32 value = 0;
 for (int32 i = bits - 1; i >= 0; --i)
 if (ReadBit())
 value |= (1 << (i));
 
 return value;
 }
 
 template <typename T>
 void put(std::size_t pos, T value)
 {
 static_assert(std::is_trivially_copyable<T>::value, "put(size_t, T) must be used with trivially copyable types");
 EndianConvert(value);
 put(pos, (uint8 *)&value, sizeof(value));
 }
 
 void PutBits(std::size_t pos, std::size_t value, uint32 bitCount);
 
 ByteBuffer &operator<<(uint8 value)
 {
 append<uint8>(value);
 return *this;
 }
 
 ByteBuffer &operator<<(uint16 value)
 {
 append<uint16>(value);
 return *this;
 }
 
 ByteBuffer &operator<<(uint32 value)
 {
 append<uint32>(value);
 return *this;
 }
 
 ByteBuffer &operator<<(uint64 value)
 {
 append<uint64>(value);
 return *this;
 }
 
 // signed as in 2e complement
 ByteBuffer &operator<<(int8 value)
 {
 append<int8>(value);
 return *this;
 }
 
 ByteBuffer &operator<<(int16 value)
 {
 append<int16>(value);
 return *this;
 }
 
 ByteBuffer &operator<<(int32 value)
 {
 append<int32>(value);
 return *this;
 }
 
 ByteBuffer &operator<<(int64 value)
 {
 append<int64>(value);
 return *this;
 }
 
 // floating points
 ByteBuffer &operator<<(float value)
 {
 append<float>(value);
 return *this;
 }
 
 ByteBuffer &operator<<(double value)
 {
 append<double>(value);
 return *this;
 }
 
 ByteBuffer &operator<<(std::string_view value)
 {
 if (size_t len = value.length())
 append(reinterpret_cast<uint8 const*>(value.data()), len);
 append(static_cast<uint8>(0));
 return *this;
 }
 
 ByteBuffer& operator<<(std::string const& str)
 {
 return operator<<(std::string_view(str));
 }
 
 ByteBuffer &operator<<(char const* str)
 {
 return operator<<(std::string_view(str ? str : ""));
 }
 
 ByteBuffer &operator>>(bool &value)
 {
 value = read<char>() > 0 ? true : false;
 return *this;
 }
 
 ByteBuffer &operator>>(uint8 &value)
 {
 value = read<uint8>();
 return *this;
 }
 
 ByteBuffer &operator>>(uint16 &value)
 {
 value = read<uint16>();
 return *this;
 }
 
 ByteBuffer &operator>>(uint32 &value)
 {
 value = read<uint32>();
 return *this;
 }
 
 ByteBuffer &operator>>(uint64 &value)
 {
 value = read<uint64>();
 return *this;
 }
 
 //signed as in 2e complement
 ByteBuffer &operator>>(int8 &value)
 {
 value = read<int8>();
 return *this;
 }
 
 ByteBuffer &operator>>(int16 &value)
 {
 value = read<int16>();
 return *this;
 }
 
 ByteBuffer &operator>>(int32 &value)
 {
 value = read<int32>();
 return *this;
 }
 
 ByteBuffer &operator>>(int64 &value)
 {
 value = read<int64>();
 return *this;
 }
 
 ByteBuffer &operator>>(float &value);
 ByteBuffer &operator>>(double &value);
 
 ByteBuffer& operator>>(std::string& value)
 {
 value = ReadCString(true);
 return *this;
 }
 
 uint8& operator[](size_t const pos)
 {
 if (pos >= size())
 throw ByteBufferPositionException(pos, 1, size());
 return _storage[pos];
 }
 
 uint8 const& operator[](size_t const pos) const
 {
 if (pos >= size())
 throw ByteBufferPositionException(pos, 1, size());
 return _storage[pos];
 }
 
 size_t rpos() const { return _rpos; }
 
 size_t rpos(size_t rpos_)
 {
 _rpos = rpos_;
 return _rpos;
 }
 
 void rfinish()
 {
 _rpos = wpos();
 }
 
 size_t wpos() const { return _wpos; }
 
 size_t wpos(size_t wpos_)
 {
 _wpos = wpos_;
 return _wpos;
 }
 
 size_t bitwpos() const { return _wpos * 8 + 8 - _bitpos; }
 
 size_t bitwpos(size_t newPos)
 {
 _wpos = newPos / 8;
 _bitpos = 8 - (newPos % 8);
 return _wpos * 8 + 8 - _bitpos;
 }
 
 template<typename T>
 void read_skip() { read_skip(sizeof(T)); }
 
 void read_skip(size_t skip)
 {
 if (_rpos + skip > size())
 throw ByteBufferPositionException(_rpos, skip, size());
 
 ResetBitPos();
 _rpos += skip;
 }
 
 template <typename T, typename Underlying = T>
 T read()
 {
 ResetBitPos();
 T r = read<T, Underlying>(_rpos);
 _rpos += sizeof(Underlying);
 return r;
 }
 
 template <typename T, typename Underlying = T>
 T read(size_t pos) const
 {
 if (pos + sizeof(Underlying) > size())
 throw ByteBufferPositionException(pos, sizeof(Underlying), size());
 Underlying val;
 std::memcpy(&val, &_storage[pos], sizeof(Underlying));
 EndianConvert(val);
 return static_cast<T>(val);
 }
 
 template<class T>
 void read(T* dest, size_t count)
 {
 static_assert(std::is_trivially_copyable<T>::value, "read(T*, size_t) must be used with trivially copyable types");
 return read(reinterpret_cast<uint8*>(dest), count * sizeof(T));
 }
 
 void read(uint8 *dest, size_t len)
 {
 if (_rpos + len > size())
 throw ByteBufferPositionException(_rpos, len, size());
 
 ResetBitPos();
 std::memcpy(dest, &_storage[_rpos], len);
 _rpos += len;
 }
 
 template <size_t Size>
 void read(std::array<uint8, Size>& arr)
 {
 read(arr.data(), Size);
 }
 
 void ReadPackedUInt64(uint64& guid)
 {
 guid = 0;
 ReadPackedUInt64(read<uint8>(), guid);
 }
 
 void ReadPackedUInt64(uint8 mask, uint64& value)
 {
 for (uint32 i = 0; i < 8; ++i)
 if (mask & (uint8(1) << i))
 value |= (uint64(read<uint8>()) << (i * 8));
 }
 
 void WriteString(std::string const& str)
 {
 if (size_t len = str.length())
 append(str.c_str(), len);
 }
 
 void WriteString(std::string_view str)
 {
 if (size_t len = str.length())
 append(str.data(), len);
 }
 
 void WriteString(char const* str, size_t len)
 {
 if (len)
 append(str, len);
 }
 
 std::string ReadCString(bool requireValidUtf8 = true);
 
 std::string ReadString(uint32 length, bool requireValidUtf8 = true);
 
 uint8* contents()
 {
 if (_storage.empty())
 throw ByteBufferException();
 return _storage.data();
 }
 
 uint8 const* contents() const
 {
 if (_storage.empty())
 throw ByteBufferException();
 return _storage.data();
 }
 
 size_t size() const { return _storage.size(); }
 bool empty() const { return _storage.empty(); }
 
 void resize(size_t newsize)
 {
 _storage.resize(newsize, 0);
 _rpos = 0;
 _wpos = size();
 }
 
 void reserve(size_t ressize)
 {
 if (ressize > size())
 _storage.reserve(ressize);
 }
 
 void shrink_to_fit()
 {
 _storage.shrink_to_fit();
 }
 
 void append(const char *src, size_t cnt)
 {
 return append((const uint8 *)src, cnt);
 }
 
 template<class T>
 void append(const T *src, size_t cnt)
 {
 return append((const uint8 *)src, cnt * sizeof(T));
 }
 
 void append(uint8 const* src, size_t cnt);
 
 void append(ByteBuffer const& buffer)
 {
 if (!buffer.empty())
 append(buffer.contents(), buffer.size());
 }
 
 template <size_t Size>
 void append(std::array<uint8, Size> const& arr)
 {
 append(arr.data(), Size);
 }
 
 // can be used in SMSG_MONSTER_MOVE opcode
 void appendPackXYZ(float x, float y, float z)
 {
 uint32 packed = 0;
 packed |= ((int)(x / 0.25f) & 0x7FF);
 packed |= ((int)(y / 0.25f) & 0x7FF) << 11;
 packed |= ((int)(z / 0.25f) & 0x3FF) << 22;
 *this << packed;
 }
 
 void AppendPackedUInt64(uint64 guid)
 {
 uint8 mask = 0;
 size_t pos = wpos();
 *this << uint8(mask);
 
 uint8 packed[8];
 if (size_t packedSize = PackUInt64(guid, &mask, packed))
 append(packed, packedSize);
 
 put<uint8>(pos, mask);
 }
 
 static size_t PackUInt64(uint64 value, uint8* mask, uint8* result)
 {
 size_t resultSize = 0;
 *mask = 0;
 memset(result, 0, 8);
 
 for (uint8 i = 0; value != 0; ++i)
 {
 if (value & 0xFF)
 {
 *mask |= uint8(1 << i);
 result[resultSize++] = uint8(value & 0xFF);
 }
 
 value >>= 8;
 }
 
 return resultSize;
 }
 
 void put(size_t pos, uint8 const* src, size_t cnt);
 
 void print_storage() const;
 
 void textlike() const;
 
 void hexlike() const;
 
 protected:
 size_t _rpos, _wpos, _bitpos;
 uint8 _curbitval;
 std::vector<uint8> _storage;
};
 
template<> inline std::string ByteBuffer::read<std::string>()
{
 std::string tmp;
 *this >> tmp;
 return tmp;
}
 
template<>
inline void ByteBuffer::read_skip<char*>()
{
 std::string temp;
 *this >> temp;
}
 
template<>
inline void ByteBuffer::read_skip<char const*>()
{
 read_skip<char*>();
}
 
template<>
inline void ByteBuffer::read_skip<std::string>()
{
 read_skip<char*>();
}
 
#endif