moneystr.cpp raw

   1  // Copyright (c) 2009-2010 Satoshi Nakamoto
   2  // Copyright (c) 2009-present 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  #include <util/moneystr.h>
   7  
   8  #include <consensus/amount.h>
   9  #include <tinyformat.h>
  10  #include <util/strencodings.h>
  11  #include <util/string.h>
  12  
  13  #include <cstdint>
  14  #include <optional>
  15  
  16  using util::ContainsNoNUL;
  17  using util::TrimString;
  18  
  19  std::string FormatMoney(const CAmount n)
  20  {
  21      // Note: not using straight sprintf here because we do NOT want
  22      // localized number formatting.
  23      static_assert(COIN > 1);
  24      int64_t quotient = n / COIN;
  25      int64_t remainder = n % COIN;
  26      if (n < 0) {
  27          quotient = -quotient;
  28          remainder = -remainder;
  29      }
  30      std::string str = strprintf("%d.%08d", quotient, remainder);
  31  
  32      // Right-trim excess zeros before the decimal point:
  33      int nTrim = 0;
  34      for (int i = str.size()-1; (str[i] == '0' && IsDigit(str[i-2])); --i)
  35          ++nTrim;
  36      if (nTrim)
  37          str.erase(str.size()-nTrim, nTrim);
  38  
  39      if (n < 0)
  40          str.insert(uint32_t{0}, 1, '-');
  41      return str;
  42  }
  43  
  44  
  45  std::optional<CAmount> ParseMoney(const std::string& money_string)
  46  {
  47      if (!ContainsNoNUL(money_string)) {
  48          return std::nullopt;
  49      }
  50      const std::string str = TrimString(money_string);
  51      if (str.empty()) {
  52          return std::nullopt;
  53      }
  54  
  55      std::string strWhole;
  56      int64_t nUnits = 0;
  57      const char* p = str.c_str();
  58      for (; *p; p++)
  59      {
  60          if (*p == '.')
  61          {
  62              p++;
  63              int64_t nMult = COIN / 10;
  64              while (IsDigit(*p) && (nMult > 0))
  65              {
  66                  nUnits += nMult * (*p++ - '0');
  67                  nMult /= 10;
  68              }
  69              break;
  70          }
  71          if (IsSpace(*p))
  72              return std::nullopt;
  73          if (!IsDigit(*p))
  74              return std::nullopt;
  75          strWhole.insert(strWhole.end(), *p);
  76      }
  77      if (*p) {
  78          return std::nullopt;
  79      }
  80      if (strWhole.size() > 10) // guard against 63 bit overflow
  81          return std::nullopt;
  82      if (nUnits < 0 || nUnits > COIN)
  83          return std::nullopt;
  84      int64_t nWhole = LocaleIndependentAtoi<int64_t>(strWhole);
  85      CAmount value = nWhole * COIN + nUnits;
  86  
  87      if (!MoneyRange(value)) {
  88          return std::nullopt;
  89      }
  90  
  91      return value;
  92  }
  93