neobytes/src/uint256.cpp

147 lines
3.7 KiB
C++

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2014 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include "uint256.h"
#include "utilstrencodings.h"
#include <stdio.h>
#include <string.h>
template <unsigned int BITS>
base_blob<BITS>::base_blob(const std::vector<unsigned char>& vch)
{
assert(vch.size() == sizeof(data));
memcpy(data, &vch[0], sizeof(data));
}
template <unsigned int BITS>
std::string base_blob<BITS>::GetHex() const
{
char psz[sizeof(data) * 2 + 1];
for (unsigned int i = 0; i < sizeof(data); i++)
sprintf(psz + i * 2, "%02x", data[sizeof(data) - i - 1]);
return std::string(psz, psz + sizeof(data) * 2);
}
template <unsigned int BITS>
void base_blob<BITS>::SetHex(const char* psz)
{
memset(data, 0, sizeof(data));
// skip leading spaces
while (isspace(*psz))
psz++;
// skip 0x
if (psz[0] == '0' && tolower(psz[1]) == 'x')
psz += 2;
// hex string to uint
const char* pbegin = psz;
while (::HexDigit(*psz) != -1)
psz++;
psz--;
unsigned char* p1 = (unsigned char*)data;
unsigned char* pend = p1 + WIDTH;
while (psz >= pbegin && p1 < pend) {
*p1 = ::HexDigit(*psz--);
if (psz >= pbegin) {
*p1 |= ((unsigned char)::HexDigit(*psz--) << 4);
p1++;
}
}
}
template <unsigned int BITS>
void base_blob<BITS>::SetHex(const std::string& str)
{
SetHex(str.c_str());
}
template <unsigned int BITS>
std::string base_blob<BITS>::ToString() const
{
return (GetHex());
}
// Explicit instantiations for base_blob<160>
template base_blob<160>::base_blob(const std::vector<unsigned char>&);
template std::string base_blob<160>::GetHex() const;
template std::string base_blob<160>::ToString() const;
template void base_blob<160>::SetHex(const char*);
template void base_blob<160>::SetHex(const std::string&);
// Explicit instantiations for base_blob<256>
template base_blob<256>::base_blob(const std::vector<unsigned char>&);
template std::string base_blob<256>::GetHex() const;
template std::string base_blob<256>::ToString() const;
template void base_blob<256>::SetHex(const char*);
template void base_blob<256>::SetHex(const std::string&);
static void inline HashMix(uint32_t& a, uint32_t& b, uint32_t& c)
{
// Taken from lookup3, by Bob Jenkins.
a -= c;
a ^= ((c << 4) | (c >> 28));
c += b;
b -= a;
b ^= ((a << 6) | (a >> 26));
a += c;
c -= b;
c ^= ((b << 8) | (b >> 24));
b += a;
a -= c;
a ^= ((c << 16) | (c >> 16));
c += b;
b -= a;
b ^= ((a << 19) | (a >> 13));
a += c;
c -= b;
c ^= ((b << 4) | (b >> 28));
b += a;
}
static void inline HashFinal(uint32_t& a, uint32_t& b, uint32_t& c)
{
// Taken from lookup3, by Bob Jenkins.
c ^= b;
c -= ((b << 14) | (b >> 18));
a ^= c;
a -= ((c << 11) | (c >> 21));
b ^= a;
b -= ((a << 25) | (a >> 7));
c ^= b;
c -= ((b << 16) | (b >> 16));
a ^= c;
a -= ((c << 4) | (c >> 28));
b ^= a;
b -= ((a << 14) | (a >> 18));
c ^= b;
c -= ((b << 24) | (b >> 8));
}
uint64_t uint256::GetHash(const uint256& salt) const
{
uint32_t a, b, c;
const uint32_t *pn = (const uint32_t*)data;
const uint32_t *salt_pn = (const uint32_t*)salt.data;
a = b = c = 0xdeadbeef + WIDTH;
a += pn[0] ^ salt_pn[0];
b += pn[1] ^ salt_pn[1];
c += pn[2] ^ salt_pn[2];
HashMix(a, b, c);
a += pn[3] ^ salt_pn[3];
b += pn[4] ^ salt_pn[4];
c += pn[5] ^ salt_pn[5];
HashMix(a, b, c);
a += pn[6] ^ salt_pn[6];
b += pn[7] ^ salt_pn[7];
HashFinal(a, b, c);
return ((((uint64_t)b) << 32) | c);
}