safeint.h

Go to the documentation of this file.

/*
* Safe(r) Integer Handling
* (C) 2016 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
 
#ifndef BOTAN_UTILS_SAFE_INT_H__
#define BOTAN_UTILS_SAFE_INT_H__
 
#include <botan/exceptn.h>
#include <string>
 
namespace Botan {
 
class Integer_Overflow_Detected : public Exception
   {
   public:
      Integer_Overflow_Detected(const std::string& file, int line) :
         Exception("Integer overflow detected at " + file + ":" + to_string(line))
         {}
   };
 
inline size_t checked_add(size_t x, size_t y, const char* file, int line)
   {
   // TODO: use __builtin_x_overflow on GCC and Clang
   size_t z = x + y;
   if(z < x)
      {
      throw Integer_Overflow_Detected(file, line);
      }
   return z;
   }
 
#define BOTAN_CHECKED_ADD(x,y) checked_add(x,y,__FILE__,__LINE__)
 
}
 
#endif