sudo/lib/util/ttysize.c

81 lines
2.2 KiB
C

/*
* SPDX-License-Identifier: ISC
*
* Copyright (c) 2010-2012, 2014-2015, 2023 Todd C. Miller <Todd.Miller@sudo.ws>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* This is an open source non-commercial project. Dear PVS-Studio, please check it.
* PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
*/
#include <config.h>
#include <sys/ioctl.h>
#include <stdlib.h>
#include <unistd.h>
#include <termios.h> /* for struct winsize on HP-UX */
#include <limits.h>
#include <sudo_compat.h>
#include <sudo_debug.h>
#include <sudo_util.h>
static int
get_ttysize_ioctl(int fd, int *rowp, int *colp)
{
struct winsize wsize;
debug_decl(get_ttysize_ioctl, SUDO_DEBUG_UTIL);
if (fd != -1 && sudo_isatty(fd, NULL)) {
if (ioctl(fd, TIOCGWINSZ, &wsize) == 0) {
if (wsize.ws_row != 0 && wsize.ws_col != 0) {
*rowp = wsize.ws_row;
*colp = wsize.ws_col;
debug_return_int(0);
}
}
}
debug_return_int(-1);
}
void
sudo_get_ttysize_v1(int *rowp, int *colp)
{
sudo_get_ttysize_v2(STDERR_FILENO, rowp, colp);
}
void
sudo_get_ttysize_v2(int fd, int *rowp, int *colp)
{
debug_decl(sudo_get_ttysize, SUDO_DEBUG_UTIL);
if (get_ttysize_ioctl(fd, rowp, colp) == -1) {
char *p;
/* Fall back on $LINES and $COLUMNS. */
if ((p = getenv("LINES")) == NULL ||
(*rowp = (int)sudo_strtonum(p, 1, INT_MAX, NULL)) <= 0) {
*rowp = 24;
}
if ((p = getenv("COLUMNS")) == NULL ||
(*colp = (int)sudo_strtonum(p, 1, INT_MAX, NULL)) <= 0) {
*colp = 80;
}
}
debug_return;
}