diff options
Diffstat (limited to 'usr.bin/resizewin/resizewin.c')
-rw-r--r-- | usr.bin/resizewin/resizewin.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/usr.bin/resizewin/resizewin.c b/usr.bin/resizewin/resizewin.c new file mode 100644 index 000000000000..5399ad33a0e4 --- /dev/null +++ b/usr.bin/resizewin/resizewin.c @@ -0,0 +1,129 @@ +/* + * resizewin + * + * Query terminal for size and inform the kernel + * + * Copyright 2015 EMC / Isilon Storage Division + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); +#include <sys/ioctl.h> +#include <sys/time.h> +#include <errno.h> +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <strings.h> +#include <termios.h> +#include <unistd.h> + +/* screen doesn't support ESC[18t (return terminal size) so do it the hard way */ +static const char query[] = + "\0337" /* Save cursor position */ + "\033[r" /* Scroll whole screen */ + "\033[999;999H" /* Move cursor */ + "\033[6n" /* Get cursor position */ + "\0338"; /* Restore cursor position */ +int +main(__unused int argc, __unused char **argv) +{ + struct termios old, new; + struct winsize w; + int ret, fd, cnt, err; + char data[20]; + struct timeval then, now; + + err = 0; + + if ((fd = open("/dev/tty", O_RDWR | O_NONBLOCK)) == -1) + exit(1); + + /* Disable echo */ + if (tcgetattr(fd, &old) == -1) + exit(1); + + new = old; + new.c_cflag |= (CLOCAL | CREAD); + new.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); + if (tcsetattr(fd, TCSANOW, &new) == -1) + exit(1); + + if (write(fd, query, sizeof(query)) != sizeof(query)) { + err = 1; + goto out; + } + + /* Read the response */ + bzero(data, sizeof(data)); + gettimeofday(&then, NULL); + cnt = 0; + while (1) { + ret = read(fd, data + cnt, 1); + + if (ret == -1) { + if (errno == EAGAIN) { + gettimeofday(&now, NULL); + timersub(&now, &then, &now); + if (now.tv_sec >= 2) { + fprintf(stderr, "\n\n\nTimeout reading from terminal\n"); + fprintf(stderr, "Read %d bytes, %s\n", cnt, data); + err = 1; + goto out; + } + + usleep(20000); + continue; + } + err = 1; + goto out; + } + if (data[cnt] == 'R') + break; + + cnt++; + if (cnt == sizeof(data) - 2) { + fprintf(stderr, "Response too long\n"); + err = 1; + goto out; + } + } + + /* Parse */ + if (sscanf(data, "\033[%hu;%huR", &w.ws_row, &w.ws_col) != 2) { + err = 1; + fprintf(stderr, "Unable to parse response\n"); + goto out; + } + + /* Finally, what we want */ + if (ioctl(fd, TIOCSWINSZ, &w) == -1) + err = 1; + out: + /* Restore echo */ + tcsetattr(fd, TCSANOW, &old); + + close(fd); + exit(err); +} |