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Use zlib crc32

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This wasn't possible until DolphinLib was unified due to zlib not being present for input devices.
This commit is contained in:
Pokechu22 2021-03-20 20:33:18 -07:00
parent 590f42dce4
commit c0e315e3a1
1 changed files with 11 additions and 54 deletions
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65
Source/Core/Core/HW/WiimoteEmu/Extension/BalanceBoard.cpp
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@ -8,6 +8,8 @@
#include <cassert>
#include <cstring>
#include <zlib.h>
#include "Common/BitUtils.h"
#include "Common/Common.h"
#include "Common/CommonTypes.h"
@ -167,60 +169,15 @@ double BalanceBoardExt::ConvertToKilograms(u16 sensor_weight)
void BalanceBoardExt::ComputeCalibrationChecksum()
{
std::array<u8, 0x1c> data;
u32 crc = crc32(0L, Z_NULL, 0);
crc = crc32(crc, &m_reg.calibration[4], 0xc); // Skip the first 4 bytes
crc = crc32(crc, &m_reg.calibration2[0], 0xc); // Skip the last 4 bytes (the CRC itself)
crc = crc32(crc, &m_reg.calibration[0], 2); // Hash 2 of the bytes skipped earlier
crc = crc32(crc, &m_reg.calibration3[0], 2);
data[0x00] = m_reg.calibration[0x4];
data[0x01] = m_reg.calibration[0x5];
data[0x02] = m_reg.calibration[0x6];
data[0x03] = m_reg.calibration[0x7];
data[0x04] = m_reg.calibration[0x8];
data[0x05] = m_reg.calibration[0x9];
data[0x06] = m_reg.calibration[0xa];
data[0x07] = m_reg.calibration[0xb];
data[0x08] = m_reg.calibration[0xc];
data[0x09] = m_reg.calibration[0xd];
data[0x0a] = m_reg.calibration[0xe];
data[0x0b] = m_reg.calibration[0xf];
data[0x0c] = m_reg.calibration2[0x0];
data[0x0d] = m_reg.calibration2[0x1];
data[0x0e] = m_reg.calibration2[0x2];
data[0x0f] = m_reg.calibration2[0x3];
data[0x10] = m_reg.calibration2[0x4];
data[0x11] = m_reg.calibration2[0x5];
data[0x12] = m_reg.calibration2[0x6];
data[0x13] = m_reg.calibration2[0x7];
data[0x14] = m_reg.calibration2[0x8];
data[0x15] = m_reg.calibration2[0x9];
data[0x16] = m_reg.calibration2[0xa];
data[0x17] = m_reg.calibration2[0xb];
data[0x18] = m_reg.calibration[0];
data[0x19] = m_reg.calibration[1];
data[0x1a] = m_reg.calibration3[0];
data[0x1b] = m_reg.calibration3[1];
constexpr u32 CRC_POLYNOMIAL = 0xEDB88320; // Reversed
u32 result = 0xffffffff;
for (auto byte : data)
{
// This could be cached into a table (and usually is), but since this is called infrequently and
// on a small number of bytes, don't bother.
u32 remainder = (byte ^ (result & 0xff));
for (auto bit = 0; bit < 8; bit++)
{
if (remainder & 1)
remainder = (remainder >> 1) ^ CRC_POLYNOMIAL;
else
remainder = remainder >> 1;
}
result = (result >> 8) ^ remainder;
}
result ^= 0xffffffff;
m_reg.calibration2[0x0c] = u8(result >> 24);
m_reg.calibration2[0x0d] = u8(result >> 16);
m_reg.calibration2[0x0e] = u8(result >> 8);
m_reg.calibration2[0x0f] = u8(result);
m_reg.calibration2[0x0c] = u8(crc >> 24);
m_reg.calibration2[0x0d] = u8(crc >> 16);
m_reg.calibration2[0x0e] = u8(crc >> 8);
m_reg.calibration2[0x0f] = u8(crc);
}
} // namespace WiimoteEmu