729 lines
21 KiB
C++
729 lines
21 KiB
C++
/*
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* Cppcheck - A tool for static C/C++ code analysis
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* Copyright (C) 2007-2014 Daniel Marjamäki and Cppcheck team.
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "mathlib.h"
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#include "errorlogger.h"
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#include <cmath>
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#include <cctype>
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#include <limits>
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MathLib::biguint MathLib::toULongNumber(const std::string & str)
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{
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// hexadecimal numbers:
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if (isHex(str)) {
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if (str[0] == '-') {
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biguint ret = 0;
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std::istringstream istr(str);
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istr >> std::hex >> ret;
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return ret;
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} else {
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unsigned long long ret = 0;
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std::istringstream istr(str);
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istr >> std::hex >> ret;
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return (biguint)ret;
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}
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}
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// octal numbers:
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if (isOct(str)) {
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biguint ret = 0;
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std::istringstream istr(str);
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istr >> std::oct >> ret;
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return ret;
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}
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// binary numbers:
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if (isBin(str)) {
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biguint ret = 0;
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for (std::string::size_type i = str[0] == '0'?2:3; i < str.length(); i++) {
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ret <<= 1;
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if (str[i] == '1')
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ret |= 1;
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}
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/* if (str[0] == '-')
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ret = -ret; */
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return ret;
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}
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if (isFloat(str)) {
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// Things are going to be less precise now: the value can't b represented in the biguint type.
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// Use min/max values as an approximation. See #5843
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const double doubleval = std::atof(str.c_str());
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if (doubleval > (double)std::numeric_limits<biguint>::max())
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return std::numeric_limits<biguint>::max();
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else
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return static_cast<biguint>(doubleval);
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}
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biguint ret = 0;
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std::istringstream istr(str);
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istr >> ret;
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return ret;
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}
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MathLib::bigint MathLib::toLongNumber(const std::string & str)
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{
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// hexadecimal numbers:
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if (isHex(str)) {
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if (str[0] == '-') {
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bigint ret = 0;
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std::istringstream istr(str);
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istr >> std::hex >> ret;
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return ret;
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} else {
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unsigned long long ret = 0;
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std::istringstream istr(str);
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istr >> std::hex >> ret;
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return (bigint)ret;
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}
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}
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// octal numbers:
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if (isOct(str)) {
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bigint ret = 0;
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std::istringstream istr(str);
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istr >> std::oct >> ret;
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return ret;
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}
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// binary numbers:
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if (isBin(str)) {
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bigint ret = 0;
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for (std::string::size_type i = str[0] == '0'?2:3; i < str.length(); i++) {
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ret <<= 1;
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if (str[i] == '1')
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ret |= 1;
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}
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if (str[0] == '-')
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ret = -ret;
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return ret;
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}
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if (isFloat(str)) {
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// Things are going to be less precise now: the value can't be represented in the bigint type.
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// Use min/max values as an approximation. See #5843
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const double doubleval = std::atof(str.c_str());
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if (doubleval > (double)std::numeric_limits<bigint>::max())
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return std::numeric_limits<bigint>::max();
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else if (doubleval < (double)std::numeric_limits<bigint>::min())
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return std::numeric_limits<bigint>::min();
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else
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return static_cast<bigint>(doubleval);
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}
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bigint ret = 0;
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std::istringstream istr(str);
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istr >> ret;
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return ret;
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}
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double MathLib::toDoubleNumber(const std::string &str)
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{
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if (isHex(str))
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return static_cast<double>(toLongNumber(str));
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// nullcheck
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else if (isNullValue(str))
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return 0.0;
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// otherwise, convert to double
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std::istringstream istr(str);
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double ret;
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istr >> ret;
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return ret;
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}
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template<> std::string MathLib::toString(double value)
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{
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std::ostringstream result;
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result.precision(12);
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result << value;
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if (result.str() == "-0")
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return "0.0";
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if (result.str().find(".") == std::string::npos)
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return result.str() + ".0";
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return result.str();
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}
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bool MathLib::isFloat(const std::string &s)
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{
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if (s.empty())
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return false;
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enum State {
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START, BASE_PLUSMINUS, BASE_DIGITS1, LEADING_DECIMAL, TRAILING_DECIMAL, BASE_DIGITS2, E, MANTISSA_PLUSMINUS, MANTISSA_DIGITS, F, L
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} state = START;
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for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
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switch (state) {
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case START:
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if (*it=='+' || *it=='-')
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state=BASE_PLUSMINUS;
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else if (*it=='.')
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state=LEADING_DECIMAL;
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else if (std::isdigit(*it))
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state=BASE_DIGITS1;
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else
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return false;
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break;
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case BASE_PLUSMINUS:
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if (*it=='.')
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state=LEADING_DECIMAL;
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else if (std::isdigit(*it))
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state=BASE_DIGITS1;
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else if (*it=='e' || *it=='E')
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state=E;
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else
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return false;
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break;
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case LEADING_DECIMAL:
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if (std::isdigit(*it))
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state=BASE_DIGITS2;
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else if (*it=='e' || *it=='E')
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state=E;
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else
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return false;
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break;
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case BASE_DIGITS1:
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if (*it=='e' || *it=='E')
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state=E;
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else if (*it=='.')
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state=TRAILING_DECIMAL;
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else if (!std::isdigit(*it))
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return false;
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break;
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case TRAILING_DECIMAL:
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if (*it=='e' || *it=='E')
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state=E;
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else if (*it=='f' || *it=='F')
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state=F;
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else if (*it=='l' || *it=='L')
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state=L;
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else if (std::isdigit(*it))
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state=BASE_DIGITS2;
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else
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return false;
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break;
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case BASE_DIGITS2:
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if (*it=='e' || *it=='E')
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state=E;
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else if (*it=='f' || *it=='F')
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state=F;
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else if (*it=='l' || *it=='L')
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state=L;
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else if (!std::isdigit(*it))
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return false;
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break;
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case E:
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if (*it=='+' || *it=='-')
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state=MANTISSA_PLUSMINUS;
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else if (std::isdigit(*it))
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state=MANTISSA_DIGITS;
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else
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return false;
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break;
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case MANTISSA_PLUSMINUS:
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if (!std::isdigit(*it))
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return false;
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else
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state=MANTISSA_DIGITS;
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break;
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case MANTISSA_DIGITS:
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if (*it=='f' || *it=='F')
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state=F;
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else if (*it=='l' || *it=='L')
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state=L;
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else if (!std::isdigit(*it))
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return false;
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break;
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case F:
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return false;
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case L:
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return false;
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}
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}
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return (state==BASE_DIGITS2 || state==MANTISSA_DIGITS || state==TRAILING_DECIMAL || state==F || state==L);
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}
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bool MathLib::isNegative(const std::string &s)
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{
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// remember position
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std::string::size_type n = 0;
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// eat up whitespace
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while (std::isspace(s[n])) ++n;
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// every negative number has a negative sign
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return (s[n] == '-');
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}
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bool MathLib::isPositive(const std::string &s)
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{
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return !MathLib::isNegative(s);
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}
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/*! \brief Does the string represent an octal number?
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* In case leading or trailing white space is provided, the function
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* returns false.
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* Additional information can be found here:
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* http://gcc.gnu.org/onlinedocs/gcc/Binary-constants.html
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*
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* \param[in] s The string to check. In case the string is empty, the function returns false.
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* \return Return true in case a octal number is provided and false otherwise.
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**/
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bool MathLib::isOct(const std::string& s)
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{
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enum Status {
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START, PLUSMINUS, OCTAL_PREFIX, DIGITS
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} state = START;
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for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
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switch (state) {
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case START:
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if (*it == '+' || *it == '-')
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state = PLUSMINUS;
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else if (*it == '0')
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state = OCTAL_PREFIX;
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else
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return false;
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break;
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case PLUSMINUS:
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if (*it == '0')
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state = OCTAL_PREFIX;
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else
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return false;
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break;
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case OCTAL_PREFIX:
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if (isOctalDigit(*it))
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state = DIGITS;
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else
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return false;
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break;
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case DIGITS:
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if (isOctalDigit(*it))
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state = DIGITS;
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else
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return isValidSuffix(it,s.end());
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break;
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}
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}
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return state == DIGITS;
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}
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bool MathLib::isHex(const std::string& s)
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{
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enum Status {
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START, PLUSMINUS, HEX_PREFIX, DIGIT, DIGITS
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} state = START;
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for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
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switch (state) {
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case START:
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if (*it == '+' || *it == '-')
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state = PLUSMINUS;
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else if (*it == '0')
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state = HEX_PREFIX;
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else
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return false;
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break;
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case PLUSMINUS:
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if (*it == '0')
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state = HEX_PREFIX;
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else
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return false;
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break;
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case HEX_PREFIX:
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if (*it == 'x' || *it == 'X')
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state = DIGIT;
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else
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return false;
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break;
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case DIGIT:
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if (isxdigit(*it))
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state = DIGITS;
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else
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return false;
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break;
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case DIGITS:
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if (isxdigit(*it))
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state = DIGITS;
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else
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return isValidSuffix(it,s.end());
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break;
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}
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}
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return state == DIGITS;
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}
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bool MathLib::isValidSuffix(std::string::const_iterator it, std::string::const_iterator end)
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{
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enum {START, SUFFIX_U, SUFFIX_UL, SUFFIX_ULL, SUFFIX_L, SUFFIX_LU, SUFFIX_LL, SUFFIX_LLU, SUFFIX_I, SUFFIX_I6, SUFFIX_I64} state = START;
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for (; it != end; ++it) {
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switch (state) {
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case START:
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if (*it == 'u' || *it == 'U')
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state = SUFFIX_U;
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else if (*it == 'l' || *it == 'L')
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state = SUFFIX_L;
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else if (*it == 'i')
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state = SUFFIX_I;
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else
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return false;
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break;
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case SUFFIX_U:
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if (*it == 'l' || *it == 'L')
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state = SUFFIX_UL; // UL
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else
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return false;
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break;
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case SUFFIX_UL:
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if (*it == 'l' || *it == 'L')
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state = SUFFIX_ULL; // ULL
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else
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return false;
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break;
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case SUFFIX_L:
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if (*it == 'u' || *it == 'U')
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state = SUFFIX_LU; // LU
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else if (*it == 'l' || *it == 'L')
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state = SUFFIX_LL; // LL
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else
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return false;
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break;
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case SUFFIX_LU:
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return false;
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case SUFFIX_LL:
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if (*it == 'u' || *it == 'U')
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state = SUFFIX_LLU; // LLU
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else
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return false;
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break;
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case SUFFIX_I:
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if (*it == '6')
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state = SUFFIX_I6;
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else
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return false;
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break;
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case SUFFIX_I6:
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if (*it == '4')
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state = SUFFIX_I64;
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else
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return false;
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break;
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default:
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return false;
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}
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}
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return ((state == SUFFIX_U) ||
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(state == SUFFIX_L) ||
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(state == SUFFIX_UL) ||
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(state == SUFFIX_LU) ||
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(state == SUFFIX_LL) ||
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(state == SUFFIX_ULL) ||
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(state == SUFFIX_LLU) ||
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(state == SUFFIX_I64));
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}
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/*! \brief Does the string represent a binary number?
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* In case leading or trailing white space is provided, the function
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* returns false.
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* Additional information can be found here:
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* http://gcc.gnu.org/onlinedocs/gcc/Binary-constants.html
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*
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* \param[in] s The string to check. In case the string is empty, the function returns false.
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* \return Return true in case a binary number is provided and false otherwise.
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**/
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bool MathLib::isBin(const std::string& s)
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{
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enum Status {
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START, PLUSMINUS, GNU_BIN_PREFIX, DIGIT, DIGITS
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} state = START;
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for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
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switch (state) {
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case START:
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if (*it == '+' || *it == '-')
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state = PLUSMINUS;
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else if (*it == '0')
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state = GNU_BIN_PREFIX;
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else
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return false;
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break;
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case PLUSMINUS:
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if (*it == '0')
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state = GNU_BIN_PREFIX;
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else
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return false;
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break;
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case GNU_BIN_PREFIX:
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if (*it == 'b' || *it == 'B')
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state = DIGIT;
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else
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return false;
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break;
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case DIGIT:
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if (*it == '0' || *it == '1')
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state = DIGITS;
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else
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return false;
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break;
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case DIGITS:
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if (*it == '0' || *it == '1')
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state = DIGITS;
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else
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return isValidSuffix(it,s.end());
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break;
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}
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}
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return state == DIGITS;
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}
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bool MathLib::isDec(const std::string & s)
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{
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enum Status {
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START, PLUSMINUS, DIGIT
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} state = START;
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for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
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switch (state) {
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case START:
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if (*it == '+' || *it == '-')
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state = PLUSMINUS;
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else if (isdigit(*it))
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state = DIGIT;
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else
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return false;
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break;
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case PLUSMINUS:
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if (isdigit(*it))
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state = DIGIT;
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else
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return false;
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break;
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case DIGIT:
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if (isdigit(*it))
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state = DIGIT;
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else
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return isValidSuffix(it,s.end());
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break;
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}
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}
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return state == DIGIT;
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}
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bool MathLib::isInt(const std::string & s)
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{
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return isDec(s) || isHex(s) || isOct(s) || isBin(s);
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}
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std::string MathLib::add(const std::string & first, const std::string & second)
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{
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if (MathLib::isInt(first) && MathLib::isInt(second)) {
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return toString(toLongNumber(first) + toLongNumber(second));
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}
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double d1 = toDoubleNumber(first);
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double d2 = toDoubleNumber(second);
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int count = 0;
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while (d1 > 100000.0 * d2 && toString(d1+d2)==first && ++count<5)
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d2 *= 10.0;
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while (d2 > 100000.0 * d1 && toString(d1+d2)==second && ++count<5)
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d1 *= 10.0;
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return toString(d1 + d2);
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}
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std::string MathLib::subtract(const std::string &first, const std::string &second)
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{
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if (MathLib::isInt(first) && MathLib::isInt(second)) {
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return toString(toLongNumber(first) - toLongNumber(second));
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|
}
|
|
|
|
if (first == second)
|
|
return "0.0" ;
|
|
|
|
double d1 = toDoubleNumber(first);
|
|
double d2 = toDoubleNumber(second);
|
|
|
|
int count = 0;
|
|
while (d1 > 100000.0 * d2 && toString(d1-d2)==first && ++count<5)
|
|
d2 *= 10.0;
|
|
while (d2 > 100000.0 * d1 && toString(d1-d2)==second && ++count<5)
|
|
d1 *= 10.0;
|
|
|
|
return toString(d1 - d2);
|
|
}
|
|
|
|
std::string MathLib::incdec(const std::string & var, const std::string & op)
|
|
{
|
|
if (op == "++")
|
|
return MathLib::add(var, "1");
|
|
else if (op == "--")
|
|
return MathLib::subtract(var, "1");
|
|
|
|
throw InternalError(0, std::string("Unexpected operation '") + op + "' in MathLib::incdec(). Please report this to Cppcheck developers.");
|
|
}
|
|
|
|
std::string MathLib::divide(const std::string &first, const std::string &second)
|
|
{
|
|
if (MathLib::isInt(first) && MathLib::isInt(second)) {
|
|
const bigint a = toLongNumber(first);
|
|
const bigint b = toLongNumber(second);
|
|
if (a == std::numeric_limits<bigint>::min())
|
|
throw InternalError(0, "Internal Error: Division overflow");
|
|
if (b == 0)
|
|
throw InternalError(0, "Internal Error: Division by zero");
|
|
return toString(toLongNumber(first) / b);
|
|
} else if (isNullValue(second)) {
|
|
if (isNullValue(first))
|
|
return "nan.0";
|
|
const int sign_first = (isPositive(first)) ? 1 : -1;
|
|
const int sign_second = (isPositive(second)) ? 1 : -1;
|
|
return (sign_first*sign_second == 1) ? "inf.0" : "-inf.0";
|
|
}
|
|
return toString(toDoubleNumber(first) / toDoubleNumber(second));
|
|
}
|
|
|
|
std::string MathLib::multiply(const std::string &first, const std::string &second)
|
|
{
|
|
if (MathLib::isInt(first) && MathLib::isInt(second)) {
|
|
return toString(toLongNumber(first) * toLongNumber(second));
|
|
}
|
|
return toString(toDoubleNumber(first) * toDoubleNumber(second));
|
|
}
|
|
|
|
std::string MathLib::mod(const std::string &first, const std::string &second)
|
|
{
|
|
if (MathLib::isInt(first) && MathLib::isInt(second)) {
|
|
bigint b = toLongNumber(second);
|
|
if (b == 0)
|
|
throw InternalError(0, "Internal Error: Division by zero");
|
|
return toString(toLongNumber(first) % b);
|
|
}
|
|
return toString(std::fmod(toDoubleNumber(first),toDoubleNumber(second)));
|
|
}
|
|
|
|
std::string MathLib::calculate(const std::string &first, const std::string &second, char action)
|
|
{
|
|
switch (action) {
|
|
case '+':
|
|
return MathLib::add(first, second);
|
|
|
|
case '-':
|
|
return MathLib::subtract(first, second);
|
|
|
|
case '*':
|
|
return MathLib::multiply(first, second);
|
|
|
|
case '/':
|
|
return MathLib::divide(first, second);
|
|
|
|
case '%':
|
|
return MathLib::mod(first, second);
|
|
|
|
case '&':
|
|
return MathLib::toString(MathLib::toLongNumber(first) & MathLib::toLongNumber(second));
|
|
|
|
case '|':
|
|
return MathLib::toString(MathLib::toLongNumber(first) | MathLib::toLongNumber(second));
|
|
|
|
case '^':
|
|
return MathLib::toString(MathLib::toLongNumber(first) ^ MathLib::toLongNumber(second));
|
|
|
|
default:
|
|
throw InternalError(0, std::string("Unexpected action '") + action + "' in MathLib::calculate(). Please report this to Cppcheck developers.");
|
|
}
|
|
}
|
|
|
|
std::string MathLib::sin(const std::string &tok)
|
|
{
|
|
return toString(std::sin(toDoubleNumber(tok)));
|
|
}
|
|
|
|
|
|
std::string MathLib::cos(const std::string &tok)
|
|
{
|
|
return toString(std::cos(toDoubleNumber(tok)));
|
|
}
|
|
|
|
std::string MathLib::tan(const std::string &tok)
|
|
{
|
|
return toString(std::tan(toDoubleNumber(tok)));
|
|
}
|
|
|
|
|
|
std::string MathLib::abs(const std::string &tok)
|
|
{
|
|
return toString(std::abs(toDoubleNumber(tok)));
|
|
}
|
|
|
|
bool MathLib::isEqual(const std::string &first, const std::string &second)
|
|
{
|
|
// this conversion is needed for formatting
|
|
// e.g. if first=0.1 and second=1.0E-1, the direct comparison of the strings would fail
|
|
return toString(toDoubleNumber(first)) == toString(toDoubleNumber(second));
|
|
}
|
|
|
|
bool MathLib::isNotEqual(const std::string &first, const std::string &second)
|
|
{
|
|
return !isEqual(first, second);
|
|
}
|
|
|
|
bool MathLib::isGreater(const std::string &first, const std::string &second)
|
|
{
|
|
return toDoubleNumber(first) > toDoubleNumber(second);
|
|
}
|
|
|
|
bool MathLib::isGreaterEqual(const std::string &first, const std::string &second)
|
|
{
|
|
return toDoubleNumber(first) >= toDoubleNumber(second);
|
|
}
|
|
|
|
bool MathLib::isLess(const std::string &first, const std::string &second)
|
|
{
|
|
return toDoubleNumber(first) < toDoubleNumber(second);
|
|
}
|
|
|
|
bool MathLib::isLessEqual(const std::string &first, const std::string &second)
|
|
{
|
|
return toDoubleNumber(first) <= toDoubleNumber(second);
|
|
}
|
|
|
|
/*! \brief Does the string represent the numerical value of 0?
|
|
* In case leading or trailing white space is provided, the function
|
|
* returns false.
|
|
* Requirement for this function:
|
|
* - This code is allowed to be slow because of simplicity of the code.
|
|
*
|
|
* \param[in] str The string to check. In case the string is empty, the function returns false.
|
|
* \return Return true in case the string represents a numerical null value.
|
|
**/
|
|
bool MathLib::isNullValue(const std::string &str)
|
|
{
|
|
if (str.empty() || (!std::isdigit(static_cast<unsigned char>(str[0])) && (str.size() < 1 || (str[0] != '.' && str[0] != '-' && str[0] != '+'))))
|
|
return false; // Has to be a number
|
|
|
|
for (size_t i = 0; i < str.size(); i++) {
|
|
if (std::isdigit(static_cast<unsigned char>(str[i])) && str[i] != '0') // May not contain digits other than 0
|
|
return false;
|
|
if (str[i] == 'E' || str[i] == 'e')
|
|
return true;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool MathLib::isOctalDigit(char c)
|
|
{
|
|
return (c >= '0' && c <= '7');
|
|
}
|