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

83 lines
3.2 KiB
C

/****************************************************************************
* libs/libc/time/lib_ctime.c
*
* Copyright (C) 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <time.h>
#if defined(CONFIG_LIBC_LOCALTIME) || defined(CONFIG_TIME_EXTENDED)
/****************************************************************************
* 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:
* One success a pointer to the string is returned; on failure, NULL is
* returned.
*
****************************************************************************/
FAR char *ctime(FAR const time_t *timep)
{
#ifdef CONFIG_LIBC_LOCALTIME
/* 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));
#else
return asctime(gmtime(timep));
#endif
}
#endif /* CONFIG_LIBC_LOCALTIME || CONFIG_TIME_EXTENDED */