px4-firmware/nuttx/lib/time/lib_time.c

111 lines
4.0 KiB
C

/****************************************************************************
* lib/time/lib_time.c
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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 <sys/time.h>
#include <time.h>
#ifndef CONFIG_DISABLE_CLOCK
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Function: time
*
* Description:
* Get the current calendar time as a time_t object. The function returns
* this value, and if the argument is not a null pointer, the value is also
* set to the object pointed by tloc.
*
* Note that this function is just a thin wrapper around gettimeofday()
* and is provided for compatibility. gettimeofday() is the preffered way
* to obtain system time.
*
* Parameters:
* Pointer to an object of type time_t, where the time value is stored.
* Alternativelly, this parameter can be a null pointer, in which case the
* parameter is not used, but a time_t object is still returned by the
* function.
*
* Return Value:
* The current calendar time as a time_t object. If the argument is not
* a null pointer, the return value is the same as the one stored in the
* location pointed by the argument.
*
* If the function could not retrieve the calendar time, it returns a -1
* value.
*
****************************************************************************/
time_t time(time_t *tloc)
{
struct timeval tp;
int ret;
/* Get the current time from the system */
ret = gettimeofday(&tp, NULL);
if (ret == OK)
{
/* Return the seconds since the epoch */
if (tloc)
{
*tloc = tp.tv_sec;
}
return tp.tv_sec;
}
return (time_t)ERROR;
}
#endif /* !CONFIG_DISABLE_CLOCK */