FeatherMC/src/network/PacketReader.h

74 lines
1.6 KiB
C++

#pragma once
#include "../Common.h"
#include <cstdio>
#include <cstdint>
#include <string>
using std::string;
namespace Feather::Network
{
// Class to read packet data, such as is produced by NetworkMessage
class PacketReader
{
public:
PacketReader(const uint8_t *const dataPtr)
: m_data(dataPtr), m_length(ReadVarInt())
{
}
template <typename T>
inline T Read()
{
T value = *reinterpret_cast<const T *const>(&m_data[m_offset]);
m_offset += sizeof(T);
return value;
}
inline int ReadVarInt()
{
int numRead = 0;
int result = 0;
uint8_t read;
do
{
read = Read<uint8_t>();
int value = (read & 0b01111111);
result |= (value << (7 * numRead));
numRead++;
if (numRead > 5)
{
// complain
//throw new RuntimeException("VarInt is too big");
}
} while ((read & 0b10000000) != 0);
return result;
}
string ReadString()
{
int size = ReadVarInt();
string str;
for (int i = 0; i < size; i++) {
str += Read<uint8_t>();
}
//printf("Read string of length %d: %s\n", size, str);
return str;
}
uint32_t Length() const { return m_length; }
private:
const uint8_t *const m_data;
const uint32_t m_length;
uint32_t m_offset = 0;
};
}