cppcheck/lib/mathlib.cpp

701 lines
20 KiB
C++

/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2014 Daniel Marjamäki and Cppcheck team.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "mathlib.h"
#include "errorlogger.h"
#include <string>
#include <sstream>
#include <cstdlib>
#include <cmath>
#include <cctype>
#include <limits>
MathLib::bigint MathLib::toLongNumber(const std::string &str)
{
// hexadecimal numbers:
if (isHex(str)) {
if (str[0] == '-') {
bigint ret = 0;
std::istringstream istr(str);
istr >> std::hex >> ret;
return ret;
} else {
unsigned long long ret = 0;
std::istringstream istr(str);
istr >> std::hex >> ret;
return (bigint)ret;
}
}
// octal numbers:
if (isOct(str)) {
bigint ret = 0;
std::istringstream istr(str);
istr >> std::oct >> ret;
return ret;
}
// binary numbers:
if (isBin(str)) {
bigint ret = 0;
for (std::string::size_type i = str[0] == '0'?2:3; i < str.length(); i++) {
ret <<= 1;
if (str[i] == '1')
ret |= 1;
}
if (str[0] == '-')
ret = -ret;
return ret;
}
if (isFloat(str))
return static_cast<bigint>(std::atof(str.c_str()));
bigint ret = 0;
std::istringstream istr(str);
istr >> ret;
return ret;
}
double MathLib::toDoubleNumber(const std::string &str)
{
if (isHex(str))
return static_cast<double>(toLongNumber(str));
// nullcheck
else if (isNullValue(str))
return 0.0;
// otherwise, convert to double
std::istringstream istr(str);
double ret;
istr >> ret;
return ret;
}
template<> std::string MathLib::toString(double value)
{
std::ostringstream result;
result.precision(12);
result << value;
if (result.str() == "-0")
return "0.0";
if (result.str().find(".") == std::string::npos)
return result.str() + ".0";
return result.str();
}
bool MathLib::isFloat(const std::string &s)
{
if (s.empty())
return false;
enum {START, BASE_PLUSMINUS, BASE_DIGITS1, LEADING_DECIMAL, TRAILING_DECIMAL, BASE_DIGITS2, E, MANTISSA_PLUSMINUS, MANTISSA_DIGITS, F} state = START;
for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
switch (state) {
case START:
if (*it=='+' || *it=='-')
state=BASE_PLUSMINUS;
else if (*it=='.')
state=LEADING_DECIMAL;
else if (std::isdigit(*it))
state=BASE_DIGITS1;
else
return false;
break;
case BASE_PLUSMINUS:
if (*it=='.')
state=LEADING_DECIMAL;
else if (std::isdigit(*it))
state=BASE_DIGITS1;
else if (*it=='e' || *it=='E')
state=E;
else
return false;
break;
case LEADING_DECIMAL:
if (std::isdigit(*it))
state=BASE_DIGITS2;
else if (*it=='e' || *it=='E')
state=E;
else
return false;
break;
case BASE_DIGITS1:
if (*it=='e' || *it=='E')
state=E;
else if (*it=='.')
state=TRAILING_DECIMAL;
else if (!std::isdigit(*it))
return false;
break;
case TRAILING_DECIMAL:
if (*it=='e' || *it=='E')
state=E;
else if (std::isdigit(*it))
state=BASE_DIGITS2;
else
return false;
break;
case BASE_DIGITS2:
if (*it=='e' || *it=='E')
state=E;
else if (*it=='f' || *it=='F')
state=F;
else if (!std::isdigit(*it))
return false;
break;
case E:
if (*it=='+' || *it=='-')
state=MANTISSA_PLUSMINUS;
else if (std::isdigit(*it))
state=MANTISSA_DIGITS;
else
return false;
break;
case MANTISSA_PLUSMINUS:
if (!std::isdigit(*it))
return false;
else
state=MANTISSA_DIGITS;
break;
case MANTISSA_DIGITS:
if (*it=='f' || *it=='F')
state=F;
else if (!std::isdigit(*it))
return false;
break;
case F:
return false;
}
}
return (state==BASE_DIGITS2 || state == MANTISSA_DIGITS || state == TRAILING_DECIMAL || state == F);
}
bool MathLib::isNegative(const std::string &s)
{
// remember position
std::string::size_type n = 0;
// eat up whitespace
while (std::isspace(s[n])) ++n;
// every negative number has a negative sign
return (s[n] == '-');
}
bool MathLib::isPositive(const std::string &s)
{
return !MathLib::isNegative(s);
}
/*! \brief Does the string represent an octal number?
* In case leading or trailing white space is provided, the function
* returns false.
* Additional information can be found here:
* http://gcc.gnu.org/onlinedocs/gcc/Binary-constants.html
*
* \param[in] s The string to check. In case the string is empty, the function returns false.
* \return Return true in case a octal number is provided and false otherwise.
**/
bool MathLib::isOct(const std::string& s)
{
enum {START, PLUSMINUS, OCTAL_PREFIX, DIGITS} state = START;
for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
switch (state) {
case START:
if (*it == '+' || *it == '-')
state = PLUSMINUS;
else if (*it == '0')
state = OCTAL_PREFIX;
else
return false;
break;
case PLUSMINUS:
if (*it == '0')
state = OCTAL_PREFIX;
else
return false;
break;
case OCTAL_PREFIX:
if (isOctalDigit(*it))
state = DIGITS;
else
return false;
break;
case DIGITS:
if (isOctalDigit(*it))
state = DIGITS;
else
return isValidSuffix(it,s.end());
break;
default:
return false;
}
}
return state == DIGITS;
}
bool MathLib::isHex(const std::string& s)
{
enum {START, PLUSMINUS, HEX_PREFIX, DIGIT, DIGITS} state = START;
for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
switch (state) {
case START:
if (*it == '+' || *it == '-')
state = PLUSMINUS;
else if (*it == '0')
state = HEX_PREFIX;
else
return false;
break;
case PLUSMINUS:
if (*it == '0')
state = HEX_PREFIX;
else
return false;
break;
case HEX_PREFIX:
if (*it == 'x' || *it == 'X')
state = DIGIT;
else
return false;
break;
case DIGIT:
if (isxdigit(*it))
state = DIGITS;
else
return false;
break;
case DIGITS:
if (isxdigit(*it))
state = DIGITS;
else
return isValidSuffix(it,s.end());
break;
default:
return false;
}
}
return state == DIGITS;
}
bool MathLib::isValidSuffix(std::string::const_iterator it, std::string::const_iterator end)
{
enum {START, SUFFIX_U, SUFFIX_UL, SUFFIX_ULL, SUFFIX_L, SUFFIX_LU, SUFFIX_LL, SUFFIX_LLU} state = START;
for (; it != end; ++it) {
switch (state) {
case START:
if (*it == 'u' || *it == 'U')
state = SUFFIX_U;
else if (*it == 'l' || *it == 'L')
state = SUFFIX_L;
else
return false;
break;
case SUFFIX_U:
if (*it == 'l' || *it == 'L')
state = SUFFIX_UL; // UL
else
return false;
break;
case SUFFIX_UL:
if (*it == 'l' || *it == 'L')
state = SUFFIX_ULL; // ULL
else
return false;
break;
case SUFFIX_L:
if (*it == 'u' || *it == 'U')
state = SUFFIX_LU; // LU
else if (*it == 'l' || *it == 'L')
state = SUFFIX_LL; // LL
else
return false;
break;
case SUFFIX_LU:
return false;
break;
case SUFFIX_LL:
if (*it == 'u' || *it == 'U')
state = SUFFIX_LLU; // LLU
else
return false;
break;
default:
return false;
}
}
return (state == SUFFIX_U) || (state == SUFFIX_L)
|| (state == SUFFIX_UL) || (state == SUFFIX_LU) || (state == SUFFIX_LL)
|| (state == SUFFIX_ULL) || (state == SUFFIX_LLU);
}
/*! \brief Does the string represent a binary number?
* In case leading or trailing white space is provided, the function
* returns false.
* Additional information can be found here:
* http://gcc.gnu.org/onlinedocs/gcc/Binary-constants.html
*
* \param[in] s The string to check. In case the string is empty, the function returns false.
* \return Return true in case a binary number is provided and false otherwise.
**/
bool MathLib::isBin(const std::string& s)
{
enum {START, PLUSMINUS, GNU_BIN_PREFIX, DIGIT, DIGITS} state = START;
for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
switch (state) {
case START:
if (*it == '+' || *it == '-')
state = PLUSMINUS;
else if (*it == '0')
state = GNU_BIN_PREFIX;
else
return false;
break;
case PLUSMINUS:
if (*it == '0')
state = GNU_BIN_PREFIX;
else
return false;
break;
case GNU_BIN_PREFIX:
if (*it == 'b' || *it == 'B')
state = DIGIT;
else
return false;
break;
case DIGIT:
if (*it == '0' || *it == '1')
state = DIGITS;
else
return false;
break;
case DIGITS:
if (*it == '0' || *it == '1')
state = DIGITS;
else
return isValidSuffix(it,s.end());
break;
default:
return false;
}
}
return state == DIGITS;
}
bool MathLib::isDec(const std::string & s)
{
enum {START, PLUSMINUS, DIGIT, SUFFIX} state = START;
for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
switch (state) {
case START:
if (*it == '+' || *it == '-')
state = PLUSMINUS;
else if (isdigit(*it))
state = DIGIT;
else
return false;
break;
case PLUSMINUS:
if (isdigit(*it))
state = DIGIT;
else
return false;
break;
case DIGIT:
if (isdigit(*it))
state = DIGIT;
else
return isValidSuffix(it,s.end());
break;
case SUFFIX:
break;
}
}
return state == DIGIT;
}
bool MathLib::isInt(const std::string & s)
{
return isDec(s) || isHex(s) || isOct(s);
}
std::string MathLib::add(const std::string & first, const std::string & second)
{
if (MathLib::isInt(first) && MathLib::isInt(second)) {
return toString(toLongNumber(first) + toLongNumber(second));
}
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::subtract(const std::string &first, const std::string &second)
{
if (MathLib::isInt(first) && MathLib::isInt(second)) {
return toString(toLongNumber(first) - toLongNumber(second));
}
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::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 (second == "0.0") {
if (first=="0.0" || first=="+0.0")
return "nan.0";
if (first=="-0.0")
return "-nan.0";
return (first[0] == '-') ? "-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);
}
bool MathLib::isNullValue(const std::string &s)
{
enum {START, PLUSMINUS, LEADING_ZERO, BIN_OR_HEX_PREFIX, DOT, TRAILING_ZERO, TRAILING_F, ZERO, E, E_PLUSMINUS, E_DIGIT} state = START;
for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
switch (state) {
case START:
if (*it == '+' || *it == '-')
state = PLUSMINUS;
else if (*it == '0')
state = LEADING_ZERO;
else if (*it == '.')
state = DOT;
else
return isValidSuffix(it, s.end());
break;
case PLUSMINUS:
if (*it == '0')
state = LEADING_ZERO;
else
return false;
break;
case LEADING_ZERO:
if (*it == '0')
state = LEADING_ZERO;
else if (*it == 'b' || *it == 'B')
state = BIN_OR_HEX_PREFIX;
else if (*it == 'x' || *it == 'X')
state = BIN_OR_HEX_PREFIX;
else if (*it == '.')
state = DOT;
else if (*it == 'e' || *it == 'E')
state = E;
else
return isValidSuffix(it, s.end());
break;
case BIN_OR_HEX_PREFIX:
if (*it == '0')
state = ZERO;
else
return false;
break;
case ZERO:
if (*it == '0')
state = ZERO;
else
return isValidSuffix(it, s.end());
break;
case DOT:
if (*it == '0')
state = TRAILING_ZERO;
else if (*it == 'f' || *it == 'F')
state = TRAILING_F;
else if (*it == 'e' || *it == 'E')
state = E;
else
return false;
break;
case E:
if (*it == '+' || *it == '-')
state = E_PLUSMINUS;
else if (isdigit(*it))
state = E_DIGIT;
else
return false;
break;
case E_PLUSMINUS:
if (isdigit(*it))
state = E_DIGIT;
else
return false;
break;
case E_DIGIT:
if (isdigit(*it))
state = E_DIGIT;
else if (*it == 'f' || *it == 'F')
state = TRAILING_F;
else
return false;
break;
case TRAILING_ZERO:
if (*it == '0')
state = TRAILING_ZERO;
else if (*it == 'f' || *it == 'F')
state = TRAILING_F;
else if (*it == 'e' || *it == 'E')
state = E;
else
return false;
break;
default:
return false;
}
}
return state == LEADING_ZERO || state == ZERO || state == DOT || state == E_DIGIT || state == TRAILING_ZERO || state == TRAILING_F;
}
bool MathLib::isOctalDigit(char c)
{
return (c >= '0' && c <= '7');
}