/src/uint256.h
C Header | 333 lines | 251 code | 47 blank | 35 comment | 22 complexity | dc39eba56bb3d1fa8cc32036bbee6ca1 MD5 | raw file
Possible License(s): GPL-3.0, BSD-3-Clause, 0BSD
- // Copyright (c) 2009-2010 Satoshi Nakamoto
- // Copyright (c) 2009-2014 The Bitcoin developers
- // Distributed under the MIT software license, see the accompanying
- // file COPYING or http://www.opensource.org/licenses/mit-license.php.
- #ifndef BITCOIN_UINT256_H
- #define BITCOIN_UINT256_H
- #include <assert.h>
- #include <cstring>
- #include <stdexcept>
- #include <stdint.h>
- #include <string>
- #include <vector>
- class uint_error : public std::runtime_error {
- public:
- explicit uint_error(const std::string& str) : std::runtime_error(str) {}
- };
- /** Template base class for unsigned big integers. */
- template<unsigned int BITS>
- class base_uint
- {
- protected:
- enum { WIDTH=BITS/32 };
- uint32_t pn[WIDTH];
- public:
- base_uint()
- {
- for (int i = 0; i < WIDTH; i++)
- pn[i] = 0;
- }
- base_uint(const base_uint& b)
- {
- for (int i = 0; i < WIDTH; i++)
- pn[i] = b.pn[i];
- }
- base_uint& operator=(const base_uint& b)
- {
- for (int i = 0; i < WIDTH; i++)
- pn[i] = b.pn[i];
- return *this;
- }
- base_uint(uint64_t b)
- {
- pn[0] = (unsigned int)b;
- pn[1] = (unsigned int)(b >> 32);
- for (int i = 2; i < WIDTH; i++)
- pn[i] = 0;
- }
- explicit base_uint(const std::string& str);
- explicit base_uint(const std::vector<unsigned char>& vch);
- bool operator!() const
- {
- for (int i = 0; i < WIDTH; i++)
- if (pn[i] != 0)
- return false;
- return true;
- }
- const base_uint operator~() const
- {
- base_uint ret;
- for (int i = 0; i < WIDTH; i++)
- ret.pn[i] = ~pn[i];
- return ret;
- }
- const base_uint operator-() const
- {
- base_uint ret;
- for (int i = 0; i < WIDTH; i++)
- ret.pn[i] = ~pn[i];
- ret++;
- return ret;
- }
- double getdouble() const;
- base_uint& operator=(uint64_t b)
- {
- pn[0] = (unsigned int)b;
- pn[1] = (unsigned int)(b >> 32);
- for (int i = 2; i < WIDTH; i++)
- pn[i] = 0;
- return *this;
- }
- base_uint& operator^=(const base_uint& b)
- {
- for (int i = 0; i < WIDTH; i++)
- pn[i] ^= b.pn[i];
- return *this;
- }
- base_uint& operator&=(const base_uint& b)
- {
- for (int i = 0; i < WIDTH; i++)
- pn[i] &= b.pn[i];
- return *this;
- }
- base_uint& operator|=(const base_uint& b)
- {
- for (int i = 0; i < WIDTH; i++)
- pn[i] |= b.pn[i];
- return *this;
- }
- base_uint& operator^=(uint64_t b)
- {
- pn[0] ^= (unsigned int)b;
- pn[1] ^= (unsigned int)(b >> 32);
- return *this;
- }
- base_uint& operator|=(uint64_t b)
- {
- pn[0] |= (unsigned int)b;
- pn[1] |= (unsigned int)(b >> 32);
- return *this;
- }
- base_uint& operator<<=(unsigned int shift);
- base_uint& operator>>=(unsigned int shift);
- base_uint& operator+=(const base_uint& b)
- {
- uint64_t carry = 0;
- for (int i = 0; i < WIDTH; i++)
- {
- uint64_t n = carry + pn[i] + b.pn[i];
- pn[i] = n & 0xffffffff;
- carry = n >> 32;
- }
- return *this;
- }
- base_uint& operator-=(const base_uint& b)
- {
- *this += -b;
- return *this;
- }
- base_uint& operator+=(uint64_t b64)
- {
- base_uint b;
- b = b64;
- *this += b;
- return *this;
- }
- base_uint& operator-=(uint64_t b64)
- {
- base_uint b;
- b = b64;
- *this += -b;
- return *this;
- }
- base_uint& operator*=(uint32_t b32);
- base_uint& operator*=(const base_uint& b);
- base_uint& operator/=(const base_uint& b);
- base_uint& operator++()
- {
- // prefix operator
- int i = 0;
- while (++pn[i] == 0 && i < WIDTH-1)
- i++;
- return *this;
- }
- const base_uint operator++(int)
- {
- // postfix operator
- const base_uint ret = *this;
- ++(*this);
- return ret;
- }
- base_uint& operator--()
- {
- // prefix operator
- int i = 0;
- while (--pn[i] == (uint32_t)-1 && i < WIDTH-1)
- i++;
- return *this;
- }
- const base_uint operator--(int)
- {
- // postfix operator
- const base_uint ret = *this;
- --(*this);
- return ret;
- }
- int CompareTo(const base_uint& b) const;
- bool EqualTo(uint64_t b) const;
- friend inline const base_uint operator+(const base_uint& a, const base_uint& b) { return base_uint(a) += b; }
- friend inline const base_uint operator-(const base_uint& a, const base_uint& b) { return base_uint(a) -= b; }
- friend inline const base_uint operator*(const base_uint& a, const base_uint& b) { return base_uint(a) *= b; }
- friend inline const base_uint operator/(const base_uint& a, const base_uint& b) { return base_uint(a) /= b; }
- friend inline const base_uint operator|(const base_uint& a, const base_uint& b) { return base_uint(a) |= b; }
- friend inline const base_uint operator&(const base_uint& a, const base_uint& b) { return base_uint(a) &= b; }
- friend inline const base_uint operator^(const base_uint& a, const base_uint& b) { return base_uint(a) ^= b; }
- friend inline const base_uint operator>>(const base_uint& a, int shift) { return base_uint(a) >>= shift; }
- friend inline const base_uint operator<<(const base_uint& a, int shift) { return base_uint(a) <<= shift; }
- friend inline const base_uint operator*(const base_uint& a, uint32_t b) { return base_uint(a) *= b; }
- friend inline bool operator==(const base_uint& a, const base_uint& b) { return memcmp(a.pn, b.pn, sizeof(a.pn)) == 0; }
- friend inline bool operator!=(const base_uint& a, const base_uint& b) { return memcmp(a.pn, b.pn, sizeof(a.pn)) != 0; }
- friend inline bool operator>(const base_uint& a, const base_uint& b) { return a.CompareTo(b) > 0; }
- friend inline bool operator<(const base_uint& a, const base_uint& b) { return a.CompareTo(b) < 0; }
- friend inline bool operator>=(const base_uint& a, const base_uint& b) { return a.CompareTo(b) >= 0; }
- friend inline bool operator<=(const base_uint& a, const base_uint& b) { return a.CompareTo(b) <= 0; }
- friend inline bool operator==(const base_uint& a, uint64_t b) { return a.EqualTo(b); }
- friend inline bool operator!=(const base_uint& a, uint64_t b) { return !a.EqualTo(b); }
- std::string GetHex() const;
- void SetHex(const char* psz);
- void SetHex(const std::string& str);
- std::string ToString() const;
- unsigned char* begin()
- {
- return (unsigned char*)&pn[0];
- }
- unsigned char* end()
- {
- return (unsigned char*)&pn[WIDTH];
- }
- const unsigned char* begin() const
- {
- return (unsigned char*)&pn[0];
- }
- const unsigned char* end() const
- {
- return (unsigned char*)&pn[WIDTH];
- }
- unsigned int size() const
- {
- return sizeof(pn);
- }
- /**
- * Returns the position of the highest bit set plus one, or zero if the
- * value is zero.
- */
- unsigned int bits() const;
- uint64_t GetLow64() const
- {
- assert(WIDTH >= 2);
- return pn[0] | (uint64_t)pn[1] << 32;
- }
- unsigned int GetSerializeSize(int nType, int nVersion) const
- {
- return sizeof(pn);
- }
- template<typename Stream>
- void Serialize(Stream& s, int nType, int nVersion) const
- {
- s.write((char*)pn, sizeof(pn));
- }
- template<typename Stream>
- void Unserialize(Stream& s, int nType, int nVersion)
- {
- s.read((char*)pn, sizeof(pn));
- }
- };
- /** 160-bit unsigned big integer. */
- class uint160 : public base_uint<160> {
- public:
- uint160() {}
- uint160(const base_uint<160>& b) : base_uint<160>(b) {}
- uint160(uint64_t b) : base_uint<160>(b) {}
- explicit uint160(const std::string& str) : base_uint<160>(str) {}
- explicit uint160(const std::vector<unsigned char>& vch) : base_uint<160>(vch) {}
- };
- /** 256-bit unsigned big integer. */
- class uint256 : public base_uint<256> {
- public:
- uint256() {}
- uint256(const base_uint<256>& b) : base_uint<256>(b) {}
- uint256(uint64_t b) : base_uint<256>(b) {}
- explicit uint256(const std::string& str) : base_uint<256>(str) {}
- explicit uint256(const std::vector<unsigned char>& vch) : base_uint<256>(vch) {}
-
- /**
- * The "compact" format is a representation of a whole
- * number N using an unsigned 32bit number similar to a
- * floating point format.
- * The most significant 8 bits are the unsigned exponent of base 256.
- * This exponent can be thought of as "number of bytes of N".
- * The lower 23 bits are the mantissa.
- * Bit number 24 (0x800000) represents the sign of N.
- * N = (-1^sign) * mantissa * 256^(exponent-3)
- *
- * Satoshi's original implementation used BN_bn2mpi() and BN_mpi2bn().
- * MPI uses the most significant bit of the first byte as sign.
- * Thus 0x1234560000 is compact (0x05123456)
- * and 0xc0de000000 is compact (0x0600c0de)
- *
- * Bitcoin only uses this "compact" format for encoding difficulty
- * targets, which are unsigned 256bit quantities. Thus, all the
- * complexities of the sign bit and using base 256 are probably an
- * implementation accident.
- */
- uint256& SetCompact(uint32_t nCompact, bool *pfNegative = NULL, bool *pfOverflow = NULL);
- uint32_t GetCompact(bool fNegative = false) const;
- uint64_t GetHash(const uint256& salt) const;
- };
- #endif // BITCOIN_UINT256_H