src/amount.h

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2015 The Bitcoin Core developers
   3 // Distributed under the MIT software license, see the accompanying
   4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5
   6 #ifndef BITCOIN_AMOUNT_H
   7 #define BITCOIN_AMOUNT_H
   8
   9 #include "serialize.h"
  10
  11 #include <stdlib.h>
  12 #include <string>
  13
  14 /** Amount in satoshis (Can be negative) */
  15 typedef int64_t CAmount;
  16
  17 static const CAmount COIN = 100000000;
  18 static const CAmount CENT = 1000000;
  19
  20 extern const std::string CURRENCY_UNIT;
  21
  22 /** No amount larger than this (in satoshi) is valid.
  23  *
  24  * Note that this constant is *not* the total money supply, which in Bitcoin
  25  * currently happens to be less than 21,000,000 BTC for various reasons, but
  26  * rather a sanity check. As this sanity check is used by consensus-critical
  27  * validation code, the exact value of the MAX_MONEY constant is consensus
  28  * critical; in unusual circumstances like a(nother) overflow bug that allowed
  29  * for the creation of coins out of thin air modification could lead to a fork.
  30  * */
  31 static const CAmount MAX_MONEY = 21000000 * COIN;
  32 inline bool MoneyRange(const CAmount& nValue) { return (nValue >= 0 && nValue <= MAX_MONEY); }
  33
  34 /**
  35  * Fee rate in satoshis per kilobyte: CAmount / kB
  36  */
  37 class CFeeRate
  38 {
  39 private:
  40     CAmount nSatoshisPerK; // unit is satoshis-per-1,000-bytes
  41 public:
  42     /** Fee rate of 0 satoshis per kB */
  43     CFeeRate() : nSatoshisPerK(0) { }
  44     explicit CFeeRate(const CAmount& _nSatoshisPerK): nSatoshisPerK(_nSatoshisPerK) { }
  45     /** Constructor for a fee rate in satoshis per kB. The size in bytes must not exceed (2^63 - 1)*/
  46     CFeeRate(const CAmount& nFeePaid, size_t nBytes);
  47     CFeeRate(const CFeeRate& other) { nSatoshisPerK = other.nSatoshisPerK; }
  48     /**
  49      * Return the fee in satoshis for the given size in bytes.
  50      */
  51     CAmount GetFee(size_t nBytes) const;
  52     /**
  53      * Return the fee in satoshis for a size of 1000 bytes
  54      */
  55     CAmount GetFeePerK() const { return GetFee(1000); }
  56     friend bool operator<(const CFeeRate& a, const CFeeRate& b) { return a.nSatoshisPerK < b.nSatoshisPerK; }
  57     friend bool operator>(const CFeeRate& a, const CFeeRate& b) { return a.nSatoshisPerK > b.nSatoshisPerK; }
  58     friend bool operator==(const CFeeRate& a, const CFeeRate& b) { return a.nSatoshisPerK == b.nSatoshisPerK; }
  59     friend bool operator<=(const CFeeRate& a, const CFeeRate& b) { return a.nSatoshisPerK <= b.nSatoshisPerK; }
  60     friend bool operator>=(const CFeeRate& a, const CFeeRate& b) { return a.nSatoshisPerK >= b.nSatoshisPerK; }
  61     CFeeRate& operator+=(const CFeeRate& a) { nSatoshisPerK += a.nSatoshisPerK; return *this; }
  62     std::string ToString() const;
  63
  64     ADD_SERIALIZE_METHODS;
  65
  66     template <typename Stream, typename Operation>
  67     inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
  68         READWRITE(nSatoshisPerK);
  69     }
  70 };
  71
  72 #endif //  BITCOIN_AMOUNT_H