// This file is under GNU General Public License 3.0
// see LICENSE.txt

#include "constant_time_algo.hh"

namespace pEp {
    bool constant_time_equal(const std::string &a, const std::string &b)
    {
        if (a.size() != b.size())
            return false;

        unsigned d = 0;
        for (std::size_t idx = 0; idx < a.size(); ++idx) {
            d |= (static_cast<unsigned>(a[idx]) ^ static_cast<unsigned>(b[idx]));
        }

        // if d is still 0, the strings are equal.
        return d == 0;
    }

} // end of namespace pEp