2018-03-13 22:07:03 +08:00
|
|
|
/****************************************************************************
|
2018-06-17 02:50:28 +08:00
|
|
|
* sched/clock/clock.c
|
2018-03-13 22:07:03 +08:00
|
|
|
*
|
2018-06-17 02:50:28 +08:00
|
|
|
* Copyright (C) 2015, 2018 Gregory Nutt. All rights reserved.
|
2018-03-13 22:07:03 +08:00
|
|
|
* 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>
|
|
|
|
|
|
|
|
#include <nuttx/clock.h>
|
|
|
|
|
|
|
|
/****************************************************************************
|
|
|
|
* Public Functions
|
|
|
|
****************************************************************************/
|
|
|
|
|
|
|
|
/****************************************************************************
|
|
|
|
* Name: clock
|
|
|
|
*
|
|
|
|
* Description:
|
|
|
|
* The clock() function returns the implementation's best approximation to
|
|
|
|
* the processor time used by the process since the beginning of a
|
|
|
|
* implementation-defined era related only to the process invocation.
|
|
|
|
*
|
|
|
|
* To determine the time in seconds, the value returned by clock() should
|
|
|
|
* be divided by the value of the macro CLOCKS_PER_SEC as defined in <time.h>.
|
|
|
|
*
|
|
|
|
* Input Parameters:
|
|
|
|
* None
|
|
|
|
*
|
|
|
|
* Returned Value:
|
|
|
|
* The system time in units of clock ticks is returend. If the processor
|
|
|
|
* time used is not available or its value cannot be represented, the
|
|
|
|
* function will return the value (clock_t)-1.
|
|
|
|
*
|
|
|
|
****************************************************************************/
|
|
|
|
|
|
|
|
clock_t clock(void)
|
|
|
|
{
|
|
|
|
return (clock_t)clock_systimer();
|
|
|
|
}
|