utility/CheckSnprintf.hpp

/**
 *   Copyright 2015 Pivotal Software, Inc.
 *   Copyright 2015 Pivotal Software, Inc.
 *
 *   Licensed under the Apache License, Version 2.0 (the "License");
 *   you may not use this file except in compliance with the License.
 *   You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 *   Unless required by applicable law or agreed to in writing, software
 *   distributed under the License is distributed on an "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 **/

#ifndef QUICKSTEP_UTILITY_CHECK_SNPRINTF_HPP_
#define QUICKSTEP_UTILITY_CHECK_SNPRINTF_HPP_

#include <cstddef>

#include "glog/logging.h"

namespace quickstep {

/** \addtogroup Utility
 *  @{
 */

/**
 * @brief Do DEBUG-mode checks after a call to snprintf() to make sure that it
 *        succeeded. Checks that snprintf() didn't return an error code, and
 *        that the total string length would not have overflowed a buffer's
 *        size, causing snprintf() to stop.
 *
 * @param snprintf_result The value returned by a call to snprintf().
 * @param buffer_size The size of the buffer used by snprintf().
 * @param total_written A pointer to a count of the total number of characters
 *        written into the buffer used by snprintf(). This function will
 *        add the number of characters successfully written by snprintf() to
 *        *total_written.
 **/
inline void CheckSnprintf(const int snprintf_result,
                          const std::size_t buffer_size,
                          std::size_t *total_written) {
  DCHECK_GE(snprintf_result, 0) << "snprintf() encountered an encoding error";
  *total_written += snprintf_result;
  DCHECK_LT(*total_written, buffer_size)
      << "snprintf() would have written a string of length " << *total_written
      << " (plus null-terminator), but buffer size is only " << buffer_size;
}

/** @} */

}  // namespace quickstep

#endif  // QUICKSTEP_UTILITY_CHECK_SNPRINTF_HPP_