incubator-nuttx/libs/libc/time/lib_ctime.c

/****************************************************************************
 * libs/libc/time/lib_ctime.c
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you 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.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <time.h>

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name:  ctime
 *
 * Description:
 *   ctime and ctime_r convert the time provided in seconds since the
 *   epoch to a string representation. ctime is not re-entrant; ctime_r is
 *   re-entrant.
 *
 * Input Parameters:
 *   timep - The current time represented as seconds since the epoch.
 *
 * Returned Value:
 *   On success, a pointer to the string is returned; on failure, NULL is
 *   returned.
 *
 ****************************************************************************/

FAR char *ctime(FAR const time_t *timep)
{
  /* Section 4.12.3.2 of X3.159-1989 requires that
   *    The ctime function converts the calendar time pointed to by timer
   *    to local time in the form of a string. It is equivalent to
   *    asctime(localtime(timer))
   */

  return asctime(localtime(timep));
}