px4-firmware/nuttx/lib/termios/lib_cfgetispeed.c

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/****************************************************************************
* lib/termios/lib_cfgetispeed.c
*
* Copyright (C) 2012 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 <termios.h>
#include <assert.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Public Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: cfgetispeed
*
* Descripton:
* The cfgetispeed() function shall extract the input baud rate from the
* termios structure to which the termios_p argument points.
*
* This function shall return exactly the value in the termios data
* structure, without interpretation.
*
* NON STANDARD BEHAVIOR. In Nuttx, the speed_t is defined to be uint32_t
* and the baud encodings of termios.h are the actual baud values
* themselves. Therefore, any baud value can be provided as the speed
* argument here. However, if you do so, your code will *NOT* be portable
* to other environments where speed_t is smaller and where the termios.h
* baud values are encoded! To avoid portability issues, use the baud
* definitions in termios.h!
*
* Input Parameters:
* termiosp - The termiosp argument is a pointer to a termios structure.
*
* Returned Value:
* Baud value in the termios structure (not verified).
*
****************************************************************************/
speed_t cfgetispeed(const struct termios *termios_p)
{
DEBUGASSERT(termios_p);
return termios_p->c_ispeed;
}