cosmopolitan/libc/log/getttysize.c

48 lines
2.7 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ This program is free software; you can redistribute it and/or modify │
│ it under the terms of the GNU General Public License as published by │
│ the Free Software Foundation; version 2 of the License. │
│ │
│ This program 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 │
│ General Public License for more details. │
│ │
│ You should have received a copy of the GNU General Public License │
│ along with this program; if not, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/bits/safemacros.h"
#include "libc/calls/calls.h"
#include "libc/calls/termios.h"
#include "libc/conv/conv.h"
#include "libc/log/log.h"
#include "libc/runtime/runtime.h"
#include "libc/sysv/consts/termios.h"
/**
* Returns dimensions of controlling terminal.
*
* It is recommended that programs err on the side of showing more
* information, if this value can't be obtained with certainty.
*
* @param out stores determined dimensions, only on success
* @returns -1 on error or something else on success
*/
int getttysize(int fd, struct winsize *out) {
if (isterminalinarticulate()) {
out->ws_col = strtoimax(firstnonnull(getenv("COLUMNS"), "80"), NULL, 0);
out->ws_row = strtoimax(firstnonnull(getenv("ROWS"), "40"), NULL, 0);
out->ws_xpixel = 0;
out->ws_ypixel = 0;
return 0;
} else {
return ioctl(fd, TIOCGWINSZ, out);
}
}