nuttx/libs/libc/termios/lib_ttyname.c
Xiang Xiao 2fa1e55628 libc: Implement ttyname and ttyname_r
Note: this patch can get file path from root pseudo file handle,
but a general infrastructure is setup for other file system too.

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: I86cd79ebb741f2f43fdd398bb7498c40687d949b
2021-07-09 18:23:34 -03:00

70 lines
2.5 KiB
C

/****************************************************************************
* libs/libc/termios/lib_ttyname.c
*
* 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 <errno.h>
#include <limits.h>
#include <unistd.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: ttyname
*
* Description:
* The ttyname() function shall return a pointer to a string containing
* a null-terminated pathname of the terminal associated with file
* descriptor fildes. The application shall not modify the string returned.
* The returned pointer might be invalidated or the string content might
* be overwritten by a subsequent call to ttyname(). The returned pointer
* and the string content might also be invalidated if the calling thread
* is terminated.
*
* Input Parameters:
* fd - The 'fd' argument is an open file descriptor associated with
* a terminal.
*
* Returned Value:
* Upon successful completion, ttyname() shall return a pointer to
* a string. Otherwise, a null pointer shall be returned and errno
* set to indicate the error.
*
****************************************************************************/
FAR char *ttyname(int fd)
{
static char name[TTY_NAME_MAX];
int ret;
ret = ttyname_r(fd, name, TTY_NAME_MAX);
if (ret != 0)
{
set_errno(ret);
return NULL;
}
return name;
}