mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-14 01:00:07 +00:00
110 lines
3.2 KiB
C
110 lines
3.2 KiB
C
/* `struct termios' speed frobnication functions. Linux version.
|
|
Copyright (C) 1991-2015 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <stddef.h>
|
|
#include <errno.h>
|
|
#include <termios.h>
|
|
|
|
|
|
/* This is a gross hack around a kernel bug. If the cfsetispeed functions
|
|
is called with the SPEED argument set to zero this means use the same
|
|
speed as for output. But we don't have independent input and output
|
|
speeds and therefore cannot record this.
|
|
|
|
We use an unused bit in the `c_iflag' field to keep track of this
|
|
use of `cfsetispeed'. The value here must correspond to the one used
|
|
in `tcsetattr.c'. */
|
|
#define IBAUD0 020000000000
|
|
|
|
|
|
/* Return the output baud rate stored in *TERMIOS_P. */
|
|
speed_t
|
|
cfgetospeed (termios_p)
|
|
const struct termios *termios_p;
|
|
{
|
|
return termios_p->c_cflag & (CBAUD | CBAUDEX);
|
|
}
|
|
|
|
/* Return the input baud rate stored in *TERMIOS_P.
|
|
Although for Linux there is no difference between input and output
|
|
speed, the numerical 0 is a special case for the input baud rate. It
|
|
should set the input baud rate to the output baud rate. */
|
|
speed_t
|
|
cfgetispeed (termios_p)
|
|
const struct termios *termios_p;
|
|
{
|
|
return ((termios_p->c_iflag & IBAUD0)
|
|
? 0 : termios_p->c_cflag & (CBAUD | CBAUDEX));
|
|
}
|
|
|
|
/* Set the output baud rate stored in *TERMIOS_P to SPEED. */
|
|
int
|
|
cfsetospeed (termios_p, speed)
|
|
struct termios *termios_p;
|
|
speed_t speed;
|
|
{
|
|
if ((speed & ~CBAUD) != 0
|
|
&& (speed < B57600 || speed > __MAX_BAUD))
|
|
{
|
|
__set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
|
|
#ifdef _HAVE_STRUCT_TERMIOS_C_OSPEED
|
|
termios_p->c_ospeed = speed;
|
|
#endif
|
|
termios_p->c_cflag &= ~(CBAUD | CBAUDEX);
|
|
termios_p->c_cflag |= speed;
|
|
|
|
return 0;
|
|
}
|
|
libc_hidden_def (cfsetospeed)
|
|
|
|
|
|
/* Set the input baud rate stored in *TERMIOS_P to SPEED.
|
|
Although for Linux there is no difference between input and output
|
|
speed, the numerical 0 is a special case for the input baud rate. It
|
|
should set the input baud rate to the output baud rate. */
|
|
int
|
|
cfsetispeed (termios_p, speed)
|
|
struct termios *termios_p;
|
|
speed_t speed;
|
|
{
|
|
if ((speed & ~CBAUD) != 0
|
|
&& (speed < B57600 || speed > __MAX_BAUD))
|
|
{
|
|
__set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
|
|
#ifdef _HAVE_STRUCT_TERMIOS_C_ISPEED
|
|
termios_p->c_ispeed = speed;
|
|
#endif
|
|
if (speed == 0)
|
|
termios_p->c_iflag |= IBAUD0;
|
|
else
|
|
{
|
|
termios_p->c_iflag &= ~IBAUD0;
|
|
termios_p->c_cflag &= ~(CBAUD | CBAUDEX);
|
|
termios_p->c_cflag |= speed;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
libc_hidden_def (cfsetispeed)
|