Shipwright/ZAPDTR/ZAPDUtils/StrHash.h

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#pragma once
#include <cstdint>
#include <cstdio>
#include <cstdlib>
typedef uint32_t strhash;
[[maybe_unused]] static strhash CRC32B(unsigned char* message, int32_t size)
{
int32_t byte = 0, crc = 0;
int32_t mask = 0;
crc = 0xFFFFFFFF;
for (int32_t i = 0; i < size; i++)
{
byte = message[i];
crc = crc ^ byte;
for (int32_t j = 7; j >= 0; j--)
{
mask = -(crc & 1);
crc = (crc >> 1) ^ (0xEDB88320 & mask);
}
}
return ~(uint32_t)(crc);
}
[[maybe_unused]] constexpr static strhash CRC32BCT(const char* message, int32_t size)
{
int32_t byte = 0, crc = 0;
int32_t mask = 0;
crc = 0xFFFFFFFF;
for (int32_t i = 0; i < size; i++)
{
byte = message[i];
crc = crc ^ byte;
for (int32_t j = 7; j >= 0; j--)
{
mask = -(crc & 1);
crc = (crc >> 1) ^ (0xEDB88320 & mask);
}
}
return ~(uint32_t)(crc);
}