incubator-nuttx/libs/libc/termios/lib_tcsetattr.c

100 lines
3.9 KiB
C

/****************************************************************************
* libs/libc/termios/lib_tcsetattr.c
*
* SPDX-License-Identifier: Apache-2.0
*
* 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 <sys/ioctl.h>
#include <termios.h>
#include <errno.h>
#include <nuttx/serial/tioctl.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: tcsetattr
*
* Description:
* The tcsetattr() function sets the parameters associated with the
* terminal referred to by the open file descriptor 'fd' from the termios
* structure referenced by 'termiop' as follows:
*
* If 'options' is TCSANOW, the change will occur immediately.
*
* If 'options' is TCSADRAIN, the change will occur after all output
* written to 'fd' is transmitted. This function should be used when
* changing parameters that affect output.
*
* If 'options' is TCSAFLUSH, the change will occur after all
* output written to 'fd' is transmitted, and all input so far received but
* not read will be discarded before the change is made.
*
* The tcsetattr() function will return successfully if it was able to
* perform any of the requested actions, even if some of the requested
* actions could not be performed. It will set all the attributes that
* implementation supports as requested and leave all the attributes not
* supported by the implementation unchanged. If no part of the request
* can be honoured, it will return -1 and set errno to EINVAL.
*
* The effect of tcsetattr() is undefined if the value of the termios
* structure pointed to by 'termiop' was not derived from the result of
* a call to tcgetattr() on 'fd'; an application should modify only fields
* and flags defined by this specification between the call to tcgetattr()
* and tcsetattr(), leaving all other fields and flags unmodified.
*
* Returned Value:
*
* Upon successful completion, 0 is returned. Otherwise, -1 is returned
* and errno is set to indicate the error. The following errors may be
* reported:
*
* - EBADF: The 'fd' argument is not a valid file descriptor.
* - EINTR: A signal interrupted tcsetattr().
* - EINVAL: The 'options' argument is not a supported value, or
* an attempt was made to change an attribute represented in the
* termios structure to an unsupported value.
* - ENOTTY: The file associated with 'fd' is not a terminal.
*
****************************************************************************/
int tcsetattr(int fd, int options, FAR const struct termios *termiosp)
{
if (options != TCSANOW)
{
tcdrain(fd);
}
if (options == TCSAFLUSH)
{
tcflush(fd, TCIFLUSH);
}
return ioctl(fd, TCSETS, (unsigned long)(uintptr_t)termiosp);
}