1 #include <stdexcept> 2 #include <sstream> 3 #include <iostream> 4 5 #include <boost/safe_numerics/safe_integer.hpp> 6 main(int,const char * [])7int main(int, const char *[]){ 8 // problem: checking of externally produced value can be overlooked 9 std::cout << "example 6: "; 10 std::cout << "checking of externally produced value can be overlooked" << std::endl; 11 std::cout << "Not using safe numerics" << std::endl; 12 13 std::istringstream is("12317289372189 1231287389217389217893"); 14 15 try{ 16 int x, y; 17 is >> x >> y; // get integer values from the user 18 std::cout << x << ' ' << y << std::endl; 19 std::cout << "error NOT detected!" << std::endl; 20 } 21 catch(const std::exception &){ 22 std::cout << "error detected!" << std::endl; 23 } 24 25 // solution: assign externally retrieved values to safe equivalents 26 std::cout << "Using safe numerics" << std::endl; 27 { 28 using namespace boost::safe_numerics; 29 safe<int> x, y; 30 is.seekg(0); 31 try{ 32 is >> x >> y; // get integer values from the user 33 std::cout << x << ' ' << y << std::endl; 34 std::cout << "error NOT detected!" << std::endl; 35 } 36 catch(const std::exception & e){ 37 std::cout << "error detected:" << e.what() << std::endl; 38 } 39 } 40 return 0; 41 } 42